From 9dbab972b906ecba5984aaf255c5557b9c0a2857 Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Thu, 1 Sep 2016 18:15:44 -0700
Subject: [PATCH 01/47] Emit '_this' declaration for derived classes;
 initialize it when calling 'super(...)'.

---
 src/compiler/transformers/es6.ts | 103 ++++++++++++++++++++++---------
 1 file changed, 73 insertions(+), 30 deletions(-)

diff --git a/src/compiler/transformers/es6.ts b/src/compiler/transformers/es6.ts
index 4e994c1acb0..aab894dc4ff 100644
--- a/src/compiler/transformers/es6.ts
+++ b/src/compiler/transformers/es6.ts
@@ -770,7 +770,7 @@ namespace ts {
             const statements: Statement[] = [];
             startLexicalEnvironment();
             if (constructor) {
-                addCaptureThisForNodeIfNeeded(statements, constructor);
+                declareOrCaptureThisForConstructorIfNeeded(statements, constructor, !!extendsClauseElement);
                 addDefaultValueAssignmentsIfNeeded(statements, constructor);
                 addRestParameterIfNeeded(statements, constructor, hasSynthesizedSuper);
             }
@@ -781,6 +781,13 @@ namespace ts {
                 const body = saveStateAndInvoke(constructor, hasSynthesizedSuper ? transformConstructorBodyWithSynthesizedSuper : transformConstructorBodyWithoutSynthesizedSuper);
                 addRange(statements, body);
             }
+            if (constructor ? hasSynthesizedSuper : extendsClauseElement) {
+                statements.push(
+                    createReturn(
+                        createIdentifier("_this")
+                    )
+                );
+            }
 
             addRange(statements, endLexicalEnvironment());
             const block = createBlock(
@@ -800,11 +807,11 @@ namespace ts {
         }
 
         function transformConstructorBodyWithSynthesizedSuper(node: ConstructorDeclaration) {
-            return visitNodes(node.body.statements, visitor, isStatement, 1);
+            return visitNodes(node.body.statements, visitor, isStatement, /*start*/ 1);
         }
 
         function transformConstructorBodyWithoutSynthesizedSuper(node: ConstructorDeclaration) {
-            return visitNodes(node.body.statements, visitor, isStatement, 0);
+            return visitNodes(node.body.statements, visitor, isStatement, /*start*/ 0);
         }
 
         /**
@@ -823,16 +830,27 @@ namespace ts {
             // If this is the case, or if the class has an `extends` clause but no
             // constructor, we emit a synthesized call to `_super`.
             if (constructor ? hasSynthesizedSuper : extendsClauseElement) {
-                statements.push(
-                    createStatement(
-                        createFunctionApply(
-                            createIdentifier("_super"),
-                            createThis(),
-                            createIdentifier("arguments")
-                        ),
-                        /*location*/ extendsClauseElement
-                    )
+                const superCall = createFunctionApply(
+                    createIdentifier("_super"),
+                    createThis(),
+                    createIdentifier("arguments"),
                 );
+                const superReturnValueOrThis = createLogicalOr(superCall, createThis());
+
+                statements.push(
+                    createVariableStatement(
+                        /*modifiers*/ undefined,
+                        createVariableDeclarationList([
+                            createVariableDeclaration(
+                                "_this",
+                                /*type*/ undefined,
+                                superReturnValueOrThis
+                            )
+                        ]),
+                    /*location*/ extendsClauseElement)
+                );
+
+                enableSubstitutionsForCapturedThis();
             }
         }
 
@@ -1079,6 +1097,15 @@ namespace ts {
             statements.push(forStatement);
         }
 
+        function declareOrCaptureThisForConstructorIfNeeded(statements: Statement[], ctor: ConstructorDeclaration, hasExtendsClause: boolean) {
+            if (hasExtendsClause) {
+                captureThisForNode(statements, ctor, /*initializer*/ undefined);
+            }
+            else {
+                addCaptureThisForNodeIfNeeded(statements, ctor);
+            }
+        }
+
         /**
          * Adds a statement to capture the `this` of a function declaration if it is needed.
          *
@@ -1087,24 +1114,28 @@ namespace ts {
          */
         function addCaptureThisForNodeIfNeeded(statements: Statement[], node: Node): void {
             if (node.transformFlags & TransformFlags.ContainsCapturedLexicalThis && node.kind !== SyntaxKind.ArrowFunction) {
-                enableSubstitutionsForCapturedThis();
-                const captureThisStatement = createVariableStatement(
-                    /*modifiers*/ undefined,
-                    createVariableDeclarationList([
-                        createVariableDeclaration(
-                            "_this",
-                            /*type*/ undefined,
-                            createThis()
-                        )
-                    ])
-                );
-
-                setNodeEmitFlags(captureThisStatement, NodeEmitFlags.NoComments | NodeEmitFlags.CustomPrologue);
-                setSourceMapRange(captureThisStatement, node);
-                statements.push(captureThisStatement);
+                captureThisForNode(statements, node, createThis());
             }
         }
 
+        function captureThisForNode(statements: Statement[], node: Node, initializer: Expression | undefined) {
+            enableSubstitutionsForCapturedThis();
+            const captureThisStatement = createVariableStatement(
+                /*modifiers*/ undefined,
+                createVariableDeclarationList([
+                    createVariableDeclaration(
+                        "_this",
+                        /*type*/ undefined,
+                        initializer
+                    )
+                ])
+            );
+
+            setNodeEmitFlags(captureThisStatement, NodeEmitFlags.NoComments | NodeEmitFlags.CustomPrologue);
+            setSourceMapRange(captureThisStatement, node);
+            statements.push(captureThisStatement);
+        }
+
         /**
          * Adds statements to the class body function for a class to define the members of the
          * class.
@@ -2468,11 +2499,12 @@ namespace ts {
          *
          * @param node a CallExpression.
          */
-        function visitCallExpression(node: CallExpression): LeftHandSideExpression {
+        function visitCallExpression(node: CallExpression): CallExpression | BinaryExpression {
             // We are here either because SuperKeyword was used somewhere in the expression, or
             // because we contain a SpreadElementExpression.
 
             const { target, thisArg } = createCallBinding(node.expression, hoistVariableDeclaration);
+            let resultingCall: CallExpression | BinaryExpression;
             if (node.transformFlags & TransformFlags.ContainsSpreadElementExpression) {
                 // [source]
                 //      f(...a, b)
@@ -2488,7 +2520,7 @@ namespace ts {
                 //      _super.m.apply(this, a.concat([b]))
                 //      _super.prototype.m.apply(this, a.concat([b]))
 
-                return createFunctionApply(
+                resultingCall = createFunctionApply(
                     visitNode(target, visitor, isExpression),
                     visitNode(thisArg, visitor, isExpression),
                     transformAndSpreadElements(node.arguments, /*needsUniqueCopy*/ false, /*multiLine*/ false, /*hasTrailingComma*/ false)
@@ -2505,13 +2537,24 @@ namespace ts {
                 //      _super.m.call(this, a)
                 //      _super.prototype.m.call(this, a)
 
-                return createFunctionCall(
+                resultingCall = createFunctionCall(
                     visitNode(target, visitor, isExpression),
                     visitNode(thisArg, visitor, isExpression),
                     visitNodes(node.arguments, visitor, isExpression),
                     /*location*/ node
                 );
             }
+
+            if (node.expression.kind === SyntaxKind.SuperKeyword) {
+                return createAssignment(
+                    createIdentifier("_this"),
+                    createLogicalOr(
+                        resultingCall,
+                        createThis()
+                    )
+                );
+            }
+            return resultingCall;
         }
 
         /**

From 99f1df4c0a7de520522cc3ab05aeb5e5ef92ccb9 Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Thu, 1 Sep 2016 20:31:21 -0700
Subject: [PATCH 02/47] Accepted baselines.

---
 ...sClassHeritageListMemberTypeAnnotations.js |   3 +-
 ...accessibleTypeInTypeParameterConstraint.js |   3 +-
 .../reference/abstractClassInLocalScope.js    |   3 +-
 .../abstractClassInLocalScopeIsAbstract.js    |   3 +-
 tests/baselines/reference/abstractProperty.js |   3 +-
 .../reference/abstractPropertyNegative.js     |  12 +-
 .../accessOverriddenBaseClassMember1.js       |   3 +-
 .../accessors_spec_section-4.5_inference.js   |   3 +-
 .../reference/aliasUsageInAccessorsOfClass.js |   3 +-
 .../baselines/reference/aliasUsageInArray.js  |   3 +-
 .../aliasUsageInFunctionExpression.js         |   3 +-
 .../reference/aliasUsageInGenericFunction.js  |   3 +-
 .../reference/aliasUsageInIndexerOfClass.js   |   3 +-
 .../reference/aliasUsageInObjectLiteral.js    |   3 +-
 .../reference/aliasUsageInOrExpression.js     |   3 +-
 ...aliasUsageInTypeArgumentOfExtendsClause.js |   6 +-
 .../reference/aliasUsageInVarAssignment.js    |   3 +-
 .../reference/ambiguousOverloadResolution.js  |   3 +-
 .../reference/apparentTypeSubtyping.js        |   6 +-
 .../reference/apparentTypeSupertype.js        |   3 +-
 .../reference/arrayAssignmentTest1.js         |   3 +-
 .../reference/arrayAssignmentTest2.js         |   3 +-
 .../reference/arrayBestCommonTypes.js         |   6 +-
 .../reference/arrayLiteralTypeInference.js    |   6 +-
 tests/baselines/reference/arrayLiterals.js    |   6 +-
 .../arrayLiteralsWithRecursiveGenerics.js     |   3 +-
 ...rayOfSubtypeIsAssignableToReadonlyArray.js |   6 +-
 .../reference/arrowFunctionContexts.js        |   8 +-
 .../assignmentCompatWithCallSignatures3.js    |   9 +-
 .../assignmentCompatWithCallSignatures4.js    |   9 +-
 .../assignmentCompatWithCallSignatures5.js    |   9 +-
 .../assignmentCompatWithCallSignatures6.js    |   9 +-
 ...ssignmentCompatWithConstructSignatures3.js |   9 +-
 ...ssignmentCompatWithConstructSignatures4.js |   9 +-
 ...ssignmentCompatWithConstructSignatures5.js |   9 +-
 ...ssignmentCompatWithConstructSignatures6.js |   9 +-
 .../assignmentCompatWithNumericIndexer.js     |   3 +-
 .../assignmentCompatWithNumericIndexer3.js    |   3 +-
 .../assignmentCompatWithObjectMembers4.js     |  12 +-
 ...nmentCompatWithObjectMembersOptionality.js |   6 +-
 ...mentCompatWithObjectMembersOptionality2.js |   6 +-
 .../assignmentCompatWithStringIndexer.js      |   6 +-
 .../reference/assignmentLHSIsValue.js         |   3 +-
 .../reference/asyncImportedPromise_es5.js     |   3 +-
 .../reference/asyncMethodWithSuper_es5.js     |   3 +-
 .../reference/asyncQualifiedReturnType_es5.js |   3 +-
 tests/baselines/reference/autolift4.js        |   3 +-
 .../reference/awaitClassExpression_es5.js     |   3 +-
 tests/baselines/reference/baseCheck.js        |  15 +-
 .../reference/baseIndexSignatureResolution.js |   3 +-
 .../reference/baseTypeOrderChecking.js        |   6 +-
 .../baseTypeWrappingInstantiationChain.js     |   6 +-
 tests/baselines/reference/bases.js            |   1 +
 .../bestCommonTypeOfConditionalExpressions.js |   6 +-
 ...bestCommonTypeOfConditionalExpressions2.js |   6 +-
 .../reference/bestCommonTypeOfTuple2.js       |   6 +-
 ...allSignatureAssignabilityInInheritance2.js |   9 +-
 ...allSignatureAssignabilityInInheritance3.js |   9 +-
 ...allSignatureAssignabilityInInheritance4.js |   9 +-
 ...allSignatureAssignabilityInInheritance5.js |   9 +-
 ...allSignatureAssignabilityInInheritance6.js |   9 +-
 tests/baselines/reference/callWithSpread.js   |   5 +-
 .../reference/captureThisInSuperCall.js       |   4 +-
 tests/baselines/reference/castingTuple.js     |   6 +-
 .../baselines/reference/chainedAssignment3.js |   3 +-
 ...arameterConstrainedToOtherTypeParameter.js |   6 +-
 .../reference/checkForObjectTooStrict.js      |   6 +-
 .../checkSuperCallBeforeThisAccessing1.js     |   3 +-
 .../checkSuperCallBeforeThisAccessing2.js     |   3 +-
 .../checkSuperCallBeforeThisAccessing3.js     |   3 +-
 .../checkSuperCallBeforeThisAccessing4.js     |   6 +-
 .../checkSuperCallBeforeThisAccessing5.js     |   3 +-
 .../checkSuperCallBeforeThisAccessing6.js     |   4 +-
 .../checkSuperCallBeforeThisAccessing7.js     |   4 +-
 .../checkSuperCallBeforeThisAccessing8.js     |   3 +-
 .../reference/circularImportAlias.js          |   3 +-
 .../circularTypeofWithFunctionModule.js       |   3 +-
 .../classAbstractConstructorAssignability.js  |   6 +-
 .../reference/classAbstractCrashedOnce.js     |   3 +-
 .../reference/classAbstractExtends.js         |  12 +-
 .../reference/classAbstractFactoryFunction.js |   3 +-
 .../reference/classAbstractGeneric.js         |  18 ++-
 .../reference/classAbstractInAModule.js       |   3 +-
 .../reference/classAbstractInheritance.js     |  24 ++-
 .../reference/classAbstractInstantiations1.js |   6 +-
 .../reference/classAbstractInstantiations2.js |  12 +-
 .../classAbstractOverrideWithAbstract.js      |  12 +-
 .../reference/classAbstractSuperCalls.js      |   9 +-
 .../classAbstractUsingAbstractMethod1.js      |   6 +-
 .../classAbstractUsingAbstractMethods2.js     |  21 ++-
 .../classConstructorAccessibility2.js         |   9 +-
 .../classConstructorAccessibility4.js         |   6 +-
 .../classConstructorAccessibility5.js         |   3 +-
 ...classConstructorParametersAccessibility.js |   3 +-
 ...lassConstructorParametersAccessibility2.js |   3 +-
 ...lassConstructorParametersAccessibility3.js |   3 +-
 ...clarationMergedInModuleWithContinuation.js |   3 +-
 .../classDoesNotDependOnBaseTypes.js          |   3 +-
 tests/baselines/reference/classExpression2.js |   3 +-
 tests/baselines/reference/classExpression3.js |   6 +-
 .../classExpressionExtendingAbstractClass.js  |   3 +-
 .../reference/classExtendingBuiltinType.js    |  30 ++--
 .../reference/classExtendingClass.js          |   6 +-
 .../reference/classExtendingClassLikeType.js  |  20 ++-
 .../reference/classExtendingNonConstructor.js |  21 ++-
 .../baselines/reference/classExtendingNull.js |   6 +-
 .../reference/classExtendingPrimitive.js      |  27 ++--
 .../reference/classExtendingPrimitive2.js     |   3 +-
 .../reference/classExtendingQualifiedName.js  |   3 +-
 .../reference/classExtendingQualifiedName2.js |   3 +-
 .../reference/classExtendsAcrossFiles.js      |   6 +-
 ...sMergedWithModuleNotReferingConstructor.js |   3 +-
 ...tendsClauseClassNotReferringConstructor.js |   3 +-
 .../reference/classExtendsEveryObjectType.js  |  18 ++-
 .../reference/classExtendsEveryObjectType2.js |   6 +-
 .../reference/classExtendsInterface.js        |   6 +-
 .../classExtendsInterfaceInExpression.js      |   3 +-
 .../classExtendsInterfaceInModule.js          |   9 +-
 .../baselines/reference/classExtendsItself.js |   9 +-
 .../reference/classExtendsItselfIndirectly.js |  18 ++-
 .../classExtendsItselfIndirectly2.js          |  18 ++-
 .../classExtendsItselfIndirectly3.js          |  18 ++-
 .../classExtendsMultipleBaseClasses.js        |   3 +-
 tests/baselines/reference/classExtendsNull.js |   4 +-
 ...classExtendsShadowedConstructorFunction.js |   3 +-
 .../classExtendsValidConstructorFunction.js   |   3 +-
 .../classHeritageWithTrailingSeparator.js     |   3 +-
 .../reference/classImplementsClass2.js        |   3 +-
 .../reference/classImplementsClass3.js        |   3 +-
 .../reference/classImplementsClass4.js        |   3 +-
 .../reference/classImplementsClass5.js        |   3 +-
 .../reference/classImplementsClass6.js        |   3 +-
 tests/baselines/reference/classIndexer3.js    |   3 +-
 tests/baselines/reference/classInheritence.js |   6 +-
 .../reference/classIsSubtypeOfBaseType.js     |   6 +-
 tests/baselines/reference/classOrder2.js      |   3 +-
 tests/baselines/reference/classOrderBug.js    |   3 +-
 .../reference/classSideInheritance1.js        |   3 +-
 .../reference/classSideInheritance2.js        |   3 +-
 .../reference/classSideInheritance3.js        |   6 +-
 tests/baselines/reference/classUpdateTests.js |  24 ++-
 .../classWithBaseClassButNoConstructor.js     |  12 +-
 .../reference/classWithConstructors.js        |   6 +-
 .../reference/classWithProtectedProperty.js   |   3 +-
 .../reference/classWithStaticMembers.js       |   3 +-
 tests/baselines/reference/classdecl.js        |   9 +-
 .../reference/clodulesDerivedClasses.js       |   3 +-
 ...llisionSuperAndLocalFunctionInAccessors.js |   6 +-
 ...isionSuperAndLocalFunctionInConstructor.js |   6 +-
 .../collisionSuperAndLocalFunctionInMethod.js |   6 +-
 ...ollisionSuperAndLocalFunctionInProperty.js |   3 +-
 .../collisionSuperAndLocalVarInAccessors.js   |   6 +-
 .../collisionSuperAndLocalVarInConstructor.js |   6 +-
 .../collisionSuperAndLocalVarInMethod.js      |   6 +-
 .../collisionSuperAndLocalVarInProperty.js    |   3 +-
 .../collisionSuperAndNameResolution.js        |   3 +-
 .../reference/collisionSuperAndParameter.js   |   6 +-
 .../reference/collisionSuperAndParameter1.js  |   3 +-
 ...perAndPropertyNameAsConstuctorParameter.js |  12 +-
 ...xpressionAndLocalVarWithSuperExperssion.js |   6 +-
 .../reference/commentsInheritance.js          |   6 +-
 .../comparisonOperatorWithIdenticalObjects.js |   6 +-
 ...ithNoRelationshipObjectsOnCallSignature.js |   3 +-
 ...lationshipObjectsOnConstructorSignature.js |   3 +-
 ...thNoRelationshipObjectsOnIndexSignature.js |   3 +-
 ...nshipObjectsOnInstantiatedCallSignature.js |   3 +-
 ...jectsOnInstantiatedConstructorSignature.js |   3 +-
 ...peratorWithSubtypeObjectOnCallSignature.js |   3 +-
 ...WithSubtypeObjectOnConstructorSignature.js |   3 +-
 ...eratorWithSubtypeObjectOnIndexSignature.js |   3 +-
 ...ubtypeObjectOnInstantiatedCallSignature.js |   3 +-
 ...bjectOnInstantiatedConstructorSignature.js |   3 +-
 ...isonOperatorWithSubtypeObjectOnProperty.js |   6 +-
 .../reference/complexClassRelationships.js    |   3 +-
 ...catedGenericRecursiveBaseClassReference.js |   3 +-
 .../reference/compoundAssignmentLHSIsValue.js |   3 +-
 ...poundExponentiationAssignmentLHSIsValue.js |   3 +-
 .../reference/computedPropertyNames24_ES5.js  |   3 +-
 .../reference/computedPropertyNames25_ES5.js  |   3 +-
 .../reference/computedPropertyNames26_ES5.js  |   3 +-
 .../reference/computedPropertyNames27_ES5.js  |   5 +-
 .../reference/computedPropertyNames28_ES5.js  |   5 +-
 .../reference/computedPropertyNames30_ES5.js  |   5 +-
 .../reference/computedPropertyNames31_ES5.js  |   3 +-
 .../reference/computedPropertyNames43_ES5.js  |   3 +-
 .../reference/computedPropertyNames44_ES5.js  |   3 +-
 .../reference/computedPropertyNames45_ES5.js  |   3 +-
 .../conditionalOperatorWithIdenticalBCT.js    |   6 +-
 .../conditionalOperatorWithoutIdenticalBCT.js |   6 +-
 .../reference/constantOverloadFunction.js     |   9 +-
 .../constantOverloadFunctionNoSubtypeError.js |   9 +-
 ...nstraintCheckInGenericBaseTypeReference.js |   3 +-
 ...uctSignatureAssignabilityInInheritance2.js |   9 +-
 ...uctSignatureAssignabilityInInheritance3.js |   9 +-
 ...uctSignatureAssignabilityInInheritance4.js |   9 +-
 ...uctSignatureAssignabilityInInheritance5.js |   9 +-
 ...uctSignatureAssignabilityInInheritance6.js |   9 +-
 tests/baselines/reference/constructorArgs.js  |   3 +-
 ...uctorFunctionTypeIsAssignableToBaseType.js |   6 +-
 ...ctorFunctionTypeIsAssignableToBaseType2.js |   6 +-
 .../constructorHasPrototypeProperty.js        |   6 +-
 .../reference/constructorOverloads2.js        |   3 +-
 .../reference/constructorOverloads3.js        |   1 +
 ...constructorWithIncompleteTypeAnnotation.js |   3 +-
 .../contextualTypingArrayOfLambdas.js         |   6 +-
 ...contextualTypingOfConditionalExpression.js |   6 +-
 ...ontextualTypingOfConditionalExpression2.js |   6 +-
 ...urcePropertyIsRelatableToTargetProperty.js |   3 +-
 .../reference/declFileClassExtendsNull.js     |   3 +-
 .../declFileForFunctionTypeAsTypeParameter.js |   3 +-
 ...ileGenericClassWithGenericExtendedClass.js |   3 +-
 .../reference/declFileGenericType.js          |   3 +-
 .../reference/declFileGenericType2.js         |   6 +-
 ...lictingWithClassReferredByExtendsClause.js |   6 +-
 ...dsClauseThatHasItsContainerNameConflict.js |   3 +-
 .../declarationEmitThisPredicates01.js        |   3 +-
 ...tionEmitThisPredicatesWithPrivateName01.js |   3 +-
 .../declarationEmit_expressionInExtends.js    |   3 +-
 .../declarationEmit_expressionInExtends2.js   |   3 +-
 .../declarationEmit_expressionInExtends3.js   |  12 +-
 .../declarationEmit_expressionInExtends4.js   |   9 +-
 .../declarationEmit_nameConflicts3.js         |   3 +-
 .../declarationEmit_protectedMembers.js       |   6 +-
 .../reference/declareDottedExtend.js          |   6 +-
 .../reference/decoratorOnClassConstructor2.js |   3 +-
 .../reference/decoratorOnClassConstructor3.js |   3 +-
 .../reference/decoratorOnClassMethod12.js     |   3 +-
 ...derivedClassConstructorWithoutSuperCall.js |  10 +-
 ...ClassFunctionOverridesBaseClassAccessor.js |   3 +-
 .../derivedClassIncludesInheritedMembers.js   |   6 +-
 ...idesIndexersWithAssignmentCompatibility.js |   6 +-
 .../derivedClassOverridesPrivateFunction1.js  |   3 +-
 .../derivedClassOverridesPrivates.js          |   6 +-
 .../derivedClassOverridesProtectedMembers.js  |   3 +-
 .../derivedClassOverridesProtectedMembers2.js |   6 +-
 .../derivedClassOverridesProtectedMembers3.js |  30 ++--
 .../derivedClassOverridesProtectedMembers4.js |   6 +-
 .../derivedClassOverridesPublicMembers.js     |   6 +-
 .../derivedClassOverridesWithoutSubtype.js    |   6 +-
 .../derivedClassParameterProperties.js        |  30 ++--
 ...dClassSuperCallsInNonConstructorMembers.js |  19 +--
 .../derivedClassSuperCallsWithThisArg.js      |  13 +-
 .../reference/derivedClassTransitivity.js     |   6 +-
 .../reference/derivedClassTransitivity2.js    |   6 +-
 .../reference/derivedClassTransitivity3.js    |   6 +-
 .../reference/derivedClassTransitivity4.js    |   6 +-
 .../reference/derivedClassWithAny.js          |   6 +-
 ...ivateInstanceShadowingProtectedInstance.js |   3 +-
 ...hPrivateInstanceShadowingPublicInstance.js |   3 +-
 ...thPrivateStaticShadowingProtectedStatic.js |   3 +-
 ...sWithPrivateStaticShadowingPublicStatic.js |   3 +-
 .../derivedClassWithoutExplicitConstructor.js |   6 +-
 ...derivedClassWithoutExplicitConstructor2.js |   6 +-
 ...derivedClassWithoutExplicitConstructor3.js |  12 +-
 tests/baselines/reference/derivedClasses.js   |   6 +-
 .../reference/derivedGenericClassWithAny.js   |   6 +-
 ...sesHiddenBaseCallViaSuperPropertyAccess.js |   3 +-
 .../derivedTypeDoesNotRequireExtendsClause.js |   3 +-
 .../destructuringParameterDeclaration5.js     |   6 +-
 ...BeforeEmitParameterPropertyDeclaration1.js |   3 +-
 ...SuperCallBeforeEmitPropertyDeclaration1.js |   3 +-
 ...arationAndParameterPropertyDeclaration1.js |   3 +-
 .../reference/emitThisInSuperMethodCall.js    |   3 +-
 tests/baselines/reference/emptyModuleName.js  |   3 +-
 ...rorForwardReferenceForwadingConstructor.js |   3 +-
 tests/baselines/reference/errorSuperCalls.js  |  32 ++--
 .../reference/errorSuperPropertyAccess.js     |   9 +-
 .../reference/errorsInGenericTypeReference.js |   3 +-
 .../reference/es6ClassSuperCodegenBug.js      |   5 +-
 tests/baselines/reference/es6ClassTest.js     |   3 +-
 tests/baselines/reference/es6ClassTest2.js    |   6 +-
 tests/baselines/reference/es6ClassTest7.js    |   3 +-
 .../exportAssignmentOfGenericType1.js         |   3 +-
 .../exportDeclarationInInternalModule.js      |   3 +-
 tests/baselines/reference/extBaseClass1.js    |   9 +-
 tests/baselines/reference/extBaseClass2.js    |   6 +-
 .../extendAndImplementTheSameBaseType.js      |   3 +-
 .../extendAndImplementTheSameBaseType2.js     |   3 +-
 .../extendBaseClassBeforeItsDeclared.js       |   3 +-
 .../extendClassExpressionFromModule.js        |   3 +-
 .../extendConstructSignatureInInterface.js    |   3 +-
 .../reference/extendNonClassSymbol1.js        |   3 +-
 .../reference/extendNonClassSymbol2.js        |   3 +-
 ...xtendingClassFromAliasAndUsageInIndexer.js |   6 +-
 .../reference/extendsClauseAlreadySeen.js     |   3 +-
 .../reference/extendsClauseAlreadySeen2.js    |   3 +-
 tests/baselines/reference/fluentClasses.js    |   6 +-
 tests/baselines/reference/for-inStatements.js |   3 +-
 .../reference/for-inStatementsInvalid.js      |   3 +-
 .../forStatementsMultipleInvalidDecl.js       |   3 +-
 .../reference/functionImplementationErrors.js |   6 +-
 .../reference/functionImplementations.js      |   6 +-
 .../reference/functionSubtypingOfVarArgs.js   |   3 +-
 .../reference/functionSubtypingOfVarArgs2.js  |   3 +-
 .../reference/generatedContextualTyping.js    |   6 +-
 .../genericBaseClassLiteralProperty.js        |   3 +-
 .../genericBaseClassLiteralProperty2.js       |   3 +-
 ...allWithConstraintsTypeArgumentInference.js |   6 +-
 .../genericCallWithObjectTypeArgs2.js         |   6 +-
 ...icCallWithObjectTypeArgsAndConstraints2.js |   3 +-
 ...icCallWithObjectTypeArgsAndConstraints3.js |   6 +-
 .../genericCallbacksAndClassHierarchy.js      |   3 +-
 .../genericClassExpressionInFunction.js       |  18 ++-
 ...sInheritsConstructorFromNonGenericClass.js |   6 +-
 ...cClassPropertyInheritanceSpecialization.js |   3 +-
 .../reference/genericClassStaticMethod.js     |   3 +-
 tests/baselines/reference/genericClasses3.js  |   3 +-
 ...genericConstraintOnExtendedBuiltinTypes.js |   3 +-
 ...enericConstraintOnExtendedBuiltinTypes2.js |   3 +-
 .../genericDerivedTypeWithSpecializedBase.js  |   3 +-
 .../genericDerivedTypeWithSpecializedBase2.js |   3 +-
 .../genericInheritedDefaultConstructors.js    |   3 +-
 .../reference/genericPrototypeProperty2.js    |   6 +-
 .../reference/genericPrototypeProperty3.js    |   6 +-
 ...ericRecursiveImplicitConstructorErrors2.js |   3 +-
 ...ericRecursiveImplicitConstructorErrors3.js |   3 +-
 .../reference/genericTypeAssertions2.js       |   3 +-
 .../reference/genericTypeAssertions4.js       |   6 +-
 .../reference/genericTypeAssertions6.js       |   3 +-
 .../reference/genericTypeConstraints.js       |   3 +-
 ...genericTypeReferenceWithoutTypeArgument.js |   6 +-
 ...enericTypeReferenceWithoutTypeArgument2.js |   6 +-
 .../genericWithIndexerOfTypeParameterType2.js |   6 +-
 .../reference/heterogeneousArrayLiterals.js   |   6 +-
 .../reference/ifDoWhileStatements.js          |   3 +-
 .../illegalSuperCallsInConstructor.js         |  11 +-
 .../implementClausePrecedingExtends.js        |   3 +-
 ...gAnInterfaceExtendingClassWithPrivates2.js |  33 ++--
 ...AnInterfaceExtendingClassWithProtecteds.js |  12 +-
 .../baselines/reference/importAsBaseClass.js  |   3 +-
 tests/baselines/reference/importHelpers.js    |   6 +-
 tests/baselines/reference/importHelpersAmd.js |   3 +-
 .../importHelpersInIsolatedModules.js         |   6 +-
 .../reference/importHelpersNoHelpers.js       |   6 +-
 .../reference/importHelpersNoModule.js        |   6 +-
 .../reference/importHelpersOutFile.js         |   6 +-
 .../reference/importHelpersSystem.js          |   3 +-
 .../reference/importShadowsGlobalName.js      |   3 +-
 .../reference/importUsedInExtendsList1.js     |   3 +-
 .../reference/indexerConstraints2.js          |  12 +-
 .../reference/indirectSelfReference.js        |   6 +-
 .../reference/indirectSelfReferenceGeneric.js |   6 +-
 .../infinitelyExpandingTypesNonGenericBase.js |   3 +-
 .../inheritFromGenericTypeParameter.js        |   3 +-
 ...SameNamePrivatePropertiesFromSameOrigin.js |   6 +-
 tests/baselines/reference/inheritance.js      |  12 +-
 tests/baselines/reference/inheritance1.js     |  12 +-
 ...itanceGrandParentPrivateMemberCollision.js |   6 +-
 ...tPrivateMemberCollisionWithPublicMember.js |   6 +-
 ...tPublicMemberCollisionWithPrivateMember.js |   6 +-
 ...ritanceMemberAccessorOverridingAccessor.js |   3 +-
 ...heritanceMemberAccessorOverridingMethod.js |   3 +-
 ...ritanceMemberAccessorOverridingProperty.js |   3 +-
 ...inheritanceMemberFuncOverridingAccessor.js |   3 +-
 .../inheritanceMemberFuncOverridingMethod.js  |   3 +-
 ...inheritanceMemberFuncOverridingProperty.js |   3 +-
 ...ritanceMemberPropertyOverridingAccessor.js |   3 +-
 ...heritanceMemberPropertyOverridingMethod.js |   3 +-
 ...ritanceMemberPropertyOverridingProperty.js |   3 +-
 .../inheritanceOfGenericConstructorMethod1.js |   3 +-
 .../inheritanceOfGenericConstructorMethod2.js |   6 +-
 ...ritanceStaticAccessorOverridingAccessor.js |   3 +-
 ...heritanceStaticAccessorOverridingMethod.js |   3 +-
 ...ritanceStaticAccessorOverridingProperty.js |   3 +-
 ...inheritanceStaticFuncOverridingAccessor.js |   3 +-
 ...eStaticFuncOverridingAccessorOfFuncType.js |   3 +-
 .../inheritanceStaticFuncOverridingMethod.js  |   3 +-
 ...inheritanceStaticFuncOverridingProperty.js |   3 +-
 ...eStaticFuncOverridingPropertyOfFuncType.js |   3 +-
 ...taticFunctionOverridingInstanceProperty.js |   3 +-
 .../inheritanceStaticMembersCompatible.js     |   3 +-
 .../inheritanceStaticMembersIncompatible.js   |   3 +-
 ...ritanceStaticPropertyOverridingAccessor.js |   3 +-
 ...heritanceStaticPropertyOverridingMethod.js |   3 +-
 ...ritanceStaticPropertyOverridingProperty.js |   3 +-
 .../inheritedConstructorWithRestParams.js     |   3 +-
 .../inheritedConstructorWithRestParams2.js    |   6 +-
 .../inheritedModuleMembersForClodule.js       |   6 +-
 .../reference/instanceOfAssignability.js      |   6 +-
 ...nstancePropertiesInheritedIntoClassType.js |   6 +-
 .../reference/instanceSubtypeCheck2.js        |   3 +-
 ...nstanceofWithStructurallyIdenticalTypes.js |   6 +-
 .../instantiatedReturnTypeContravariance.js   |   3 +-
 .../reference/interfaceClassMerging.js        |   3 +-
 .../reference/interfaceClassMerging2.js       |   3 +-
 .../reference/interfaceExtendsClass1.js       |   9 +-
 .../interfaceExtendsClassWithPrivate1.js      |   3 +-
 .../interfaceExtendsClassWithPrivate2.js      |   6 +-
 .../reference/interfaceImplementation8.js     |  12 +-
 .../invalidModuleWithStatementsOfEveryKind.js |  18 ++-
 .../invalidMultipleVariableDeclarations.js    |   3 +-
 .../reference/invalidReturnStatements.js      |   3 +-
 .../isolatedModulesImportExportElision.js     |   3 +-
 tests/baselines/reference/jsxViaImport.js     |   3 +-
 tests/baselines/reference/lambdaArgCrash.js   |   3 +-
 tests/baselines/reference/lift.js             |   3 +-
 tests/baselines/reference/localTypes1.js      |   6 +-
 tests/baselines/reference/m7Bugs.js           |   3 +-
 .../reference/mergedDeclarations5.js          |   3 +-
 .../reference/mergedDeclarations6.js          |   3 +-
 .../mergedInheritedClassInterface.js          |   6 +-
 .../mergedInterfacesWithInheritedPrivates2.js |   6 +-
 .../mergedInterfacesWithInheritedPrivates3.js |   3 +-
 .../missingPropertiesOfClassExpression.js     |   3 +-
 tests/baselines/reference/moduleAsBaseType.js |   3 +-
 .../moduleImportedForTypeArgumentPosition.js  |   3 +-
 .../moduleWithStatementsOfEveryKind.js        |  12 +-
 .../reference/multipleInheritance.js          |  18 ++-
 .../mutuallyRecursiveGenericBaseTypes2.js     |   3 +-
 tests/baselines/reference/noEmitHelpers.js    |   3 +-
 ...enericClassExtendingGenericClassWithAny.js |   3 +-
 ...cIndexerConstrainsPropertyDeclarations2.js |   3 +-
 .../reference/numericIndexerConstraint3.js    |   3 +-
 .../reference/numericIndexerConstraint4.js    |   3 +-
 .../reference/numericIndexerTyping2.js        |   3 +-
 ...objectCreationOfElementAccessExpression.js |  18 ++-
 ...objectTypeHidingMembersOfExtendedObject.js |   3 +-
 ...objectTypesIdentityWithNumericIndexers1.js |   6 +-
 ...objectTypesIdentityWithNumericIndexers2.js |   9 +-
 ...objectTypesIdentityWithNumericIndexers3.js |   6 +-
 .../objectTypesIdentityWithPrivates.js        |   6 +-
 .../objectTypesIdentityWithPrivates2.js       |   3 +-
 .../objectTypesIdentityWithPrivates3.js       |   6 +-
 .../objectTypesIdentityWithStringIndexers.js  |   6 +-
 .../objectTypesIdentityWithStringIndexers2.js |   9 +-
 .../optionalConstructorArgInSuper.js          |   3 +-
 tests/baselines/reference/optionalMethods.js  |   3 +-
 .../reference/optionalParamArgsTest.js        |   3 +-
 .../reference/optionalParamInOverride.js      |   3 +-
 .../reference/optionalParameterProperty.js    |   3 +-
 .../baselines/reference/outModuleConcatAmd.js |   3 +-
 .../reference/outModuleConcatAmd.js.map       |   2 +-
 .../outModuleConcatAmd.sourcemap.txt          |  33 ++--
 .../reference/outModuleConcatSystem.js        |   3 +-
 .../reference/outModuleConcatSystem.js.map    |   2 +-
 .../outModuleConcatSystem.sourcemap.txt       |  33 ++--
 .../reference/outModuleTripleSlashRefs.js     |   3 +-
 .../reference/outModuleTripleSlashRefs.js.map |   2 +-
 .../outModuleTripleSlashRefs.sourcemap.txt    |  33 ++--
 tests/baselines/reference/overload1.js        |   6 +-
 .../overloadOnConstConstraintChecks1.js       |   9 +-
 .../overloadOnConstConstraintChecks2.js       |   6 +-
 .../overloadOnConstConstraintChecks3.js       |   6 +-
 .../overloadOnConstConstraintChecks4.js       |   9 +-
 .../overloadOnConstantsInvalidOverload1.js    |   9 +-
 .../baselines/reference/overloadResolution.js |   9 +-
 .../overloadResolutionClassConstructors.js    |   9 +-
 .../overloadResolutionConstructors.js         |   9 +-
 .../reference/overloadingOnConstants1.js      |   9 +-
 .../reference/overloadingOnConstants2.js      |   3 +-
 .../overridingPrivateStaticMembers.js         |   3 +-
 .../reference/parseErrorInHeritageClause1.js  |   3 +-
 tests/baselines/reference/parser509630.js     |   3 +-
 tests/baselines/reference/parserAstSpans1.js  |   9 +-
 .../reference/parserClassDeclaration1.js      |   3 +-
 .../reference/parserClassDeclaration3.js      |   3 +-
 .../reference/parserClassDeclaration4.js      |   3 +-
 .../reference/parserClassDeclaration5.js      |   3 +-
 .../reference/parserClassDeclaration6.js      |   3 +-
 ...rrorRecovery_ExtendsOrImplementsClause2.js |   3 +-
 ...rrorRecovery_ExtendsOrImplementsClause4.js |   3 +-
 ...rrorRecovery_ExtendsOrImplementsClause5.js |   3 +-
 .../parserGenericsInTypeContexts1.js          |   3 +-
 .../parserGenericsInTypeContexts2.js          |   3 +-
 .../baselines/reference/parserRealSource10.js |  18 ++-
 .../baselines/reference/parserRealSource11.js | 144 ++++++++++++------
 tests/baselines/reference/parserharness.js    |   9 +-
 tests/baselines/reference/primitiveMembers.js |   3 +-
 tests/baselines/reference/privacyClass.js     |  72 ++++++---
 .../privacyClassExtendsClauseDeclFile.js      |  69 ++++++---
 tests/baselines/reference/privacyGloClass.js  |  30 ++--
 .../reference/privateAccessInSubclass1.js     |   3 +-
 .../privateInstanceMemberAccessibility.js     |   3 +-
 ...tedMembersAreNotAccessibleDestructuring.js |   3 +-
 .../privateStaticMemberAccessibility.js       |   3 +-
 .../privateStaticNotAccessibleInClodule2.js   |   3 +-
 .../amd/testGlo.js                            |  12 +-
 .../node/testGlo.js                           |  12 +-
 .../reference/project/prologueEmit/amd/out.js |   3 +-
 .../project/prologueEmit/node/out.js          |   3 +-
 .../amd/m'ain.js                              |   3 +-
 .../node/m'ain.js                             |   3 +-
 .../reference/propertiesAndIndexers.js        |   3 +-
 tests/baselines/reference/propertyAccess.js   |   3 +-
 ...tyAccessOnTypeParameterWithConstraints2.js |   3 +-
 ...tyAccessOnTypeParameterWithConstraints3.js |   3 +-
 ...tyAccessOnTypeParameterWithConstraints5.js |   3 +-
 ...sPropertyAccessibleWithinNestedSubclass.js |   6 +-
 ...PropertyAccessibleWithinNestedSubclass1.js |  12 +-
 ...edClassPropertyAccessibleWithinSubclass.js |   3 +-
 ...dClassPropertyAccessibleWithinSubclass2.js |  12 +-
 ...dClassPropertyAccessibleWithinSubclass3.js |   3 +-
 .../protectedInstanceMemberAccessibility.js   |   6 +-
 tests/baselines/reference/protectedMembers.js |  21 ++-
 ...icClassPropertyAccessibleWithinSubclass.js |   9 +-
 ...cClassPropertyAccessibleWithinSubclass2.js |   6 +-
 ...solution-does-not-affect-class-heritage.js |   3 +-
 .../readonlyConstructorAssignment.js          |   9 +-
 .../reference/recursiveBaseCheck3.js          |   6 +-
 .../reference/recursiveBaseCheck4.js          |   3 +-
 .../reference/recursiveBaseCheck6.js          |   3 +-
 .../recursiveBaseConstructorCreation1.js      |   3 +-
 ...ssInstantiationsWithDefaultConstructors.js |   3 +-
 .../reference/recursiveClassReferenceTest.js  |   3 +-
 .../recursiveClassReferenceTest.js.map        |   2 +-
 .../recursiveClassReferenceTest.sourcemap.txt | 137 ++++++++---------
 .../reference/recursiveComplicatedClasses.js  |   9 +-
 ...sivelySpecializedConstructorDeclaration.js |   3 +-
 .../reference/reexportClassDefinition.js      |   3 +-
 ...lassDeclarationWhenInBaseTypeResolution.js | 141 +++++++++++------
 .../reference/returnInConstructor1.js         |   6 +-
 tests/baselines/reference/returnStatements.js |   3 +-
 ...peCheckExtendedClassInsidePublicMethod2.js |   3 +-
 ...peCheckExtendedClassInsideStaticMethod1.js |   3 +-
 tests/baselines/reference/scopeTests.js       |   3 +-
 .../reference/shadowPrivateMembers.js         |   3 +-
 ...sWithDefaultConstructorAndExtendsClause.js |   3 +-
 ...hDefaultConstructorAndExtendsClause.js.map |   2 +-
 ...tConstructorAndExtendsClause.sourcemap.txt |  59 ++++---
 .../specializedInheritedConstructors1.js      |   3 +-
 .../specializedOverloadWithRestParameters.js  |   3 +-
 tests/baselines/reference/staticFactory1.js   |   3 +-
 .../baselines/reference/staticInheritance.js  |   3 +-
 .../staticMemberAccessOffDerivedType1.js      |   3 +-
 tests/baselines/reference/staticPropSuper.js  |   6 +-
 .../reference/strictModeInConstructor.js      |  18 ++-
 .../reference/strictModeReservedWord.js       |   3 +-
 ...trictModeReservedWordInClassDeclaration.js |   6 +-
 ...gIndexerConstrainsPropertyDeclarations2.js |   3 +-
 .../reference/subtypesOfTypeParameter.js      |   3 +-
 .../subtypesOfTypeParameterWithConstraints.js |  87 +++++++----
 ...subtypesOfTypeParameterWithConstraints4.js |  27 ++--
 ...OfTypeParameterWithRecursiveConstraints.js |  54 ++++---
 .../reference/subtypingTransitivity.js        |   6 +-
 .../reference/subtypingWithCallSignatures2.js |   9 +-
 .../reference/subtypingWithCallSignatures3.js |   9 +-
 .../reference/subtypingWithCallSignatures4.js |   9 +-
 .../subtypingWithConstructSignatures2.js      |   9 +-
 .../subtypingWithConstructSignatures3.js      |   9 +-
 .../subtypingWithConstructSignatures4.js      |   9 +-
 .../subtypingWithConstructSignatures5.js      |   9 +-
 .../subtypingWithConstructSignatures6.js      |   9 +-
 .../reference/subtypingWithNumericIndexer.js  |  18 ++-
 .../reference/subtypingWithNumericIndexer3.js |  21 ++-
 .../reference/subtypingWithNumericIndexer4.js |   9 +-
 .../reference/subtypingWithObjectMembers.js   |  24 ++-
 .../reference/subtypingWithObjectMembers4.js  |  12 +-
 ...subtypingWithObjectMembersAccessibility.js |  12 +-
 ...ubtypingWithObjectMembersAccessibility2.js |  21 ++-
 .../reference/subtypingWithStringIndexer.js   |  18 ++-
 .../reference/subtypingWithStringIndexer3.js  |  21 ++-
 .../reference/subtypingWithStringIndexer4.js  |   9 +-
 tests/baselines/reference/super.js            |   6 +-
 tests/baselines/reference/super1.js           |  15 +-
 tests/baselines/reference/super2.js           |  12 +-
 tests/baselines/reference/superAccess.js      |   3 +-
 tests/baselines/reference/superAccess2.js     |   4 +-
 .../reference/superAccessInFatArrow1.js       |   3 +-
 .../reference/superCallArgsMustMatch.js       |   3 +-
 .../reference/superCallAssignResult.js        |   3 +-
 .../superCallBeforeThisAccessing1.js          |   3 +-
 .../superCallBeforeThisAccessing2.js          |   4 +-
 .../superCallBeforeThisAccessing3.js          |   4 +-
 .../superCallBeforeThisAccessing4.js          |   6 +-
 .../superCallBeforeThisAccessing5.js          |   1 +
 .../superCallBeforeThisAccessing6.js          |   3 +-
 .../superCallBeforeThisAccessing7.js          |   3 +-
 .../superCallBeforeThisAccessing8.js          |   3 +-
 ...allFromClassThatDerivesFromGenericType1.js |   3 +-
 ...allFromClassThatDerivesFromGenericType2.js |   3 +-
 ...eButWithIncorrectNumberOfTypeArguments1.js |   3 +-
 ...sFromGenericTypeButWithNoTypeArguments1.js |   3 +-
 ...ivesNonGenericTypeButWithTypeArguments1.js |   3 +-
 .../superCallFromClassThatHasNoBaseType1.js   |   2 +-
 .../reference/superCallFromFunction1.js       |   2 +-
 .../superCallInConstructorWithNoBaseType.js   |   4 +-
 .../reference/superCallInNonStaticMethod.js   |   4 +-
 .../reference/superCallInStaticMethod.js      |   3 +-
 .../superCallInsideClassDeclaration.js        |   4 +-
 .../superCallInsideClassExpression.js         |   4 +-
 .../superCallInsideObjectLiteralExpression.js |   3 +-
 .../reference/superCallOutsideConstructor.js  |   9 +-
 .../superCallParameterContextualTyping1.js    |   3 +-
 .../superCallParameterContextualTyping2.js    |   3 +-
 .../superCallParameterContextualTyping3.js    |   5 +-
 .../superCallWithMissingBaseClass.js          |   3 +-
 tests/baselines/reference/superCalls.js       |   8 +-
 .../reference/superCallsInConstructor.js      |   5 +-
 tests/baselines/reference/superErrors.js      |   3 +-
 .../baselines/reference/superInCatchBlock1.js |   3 +-
 .../reference/superInConstructorParam1.js     |   1 +
 tests/baselines/reference/superInLambdas.js   |  16 +-
 .../reference/superInObjectLiterals_ES5.js    |   3 +-
 tests/baselines/reference/superNewCall1.js    |   1 +
 .../reference/superPropertyAccess.js          |   3 +-
 .../reference/superPropertyAccess1.js         |   3 +-
 .../reference/superPropertyAccess2.js         |   3 +-
 ...essInComputedPropertiesOfNestedType_ES5.js |   3 +-
 .../reference/superPropertyAccessNoError.js   |   3 +-
 .../reference/superPropertyAccess_ES5.js      |   6 +-
 .../reference/superSymbolIndexedAccess5.js    |   3 +-
 .../reference/superSymbolIndexedAccess6.js    |   3 +-
 .../superWithGenericSpecialization.js         |   3 +-
 .../baselines/reference/superWithGenerics.js  |   3 +-
 .../reference/superWithTypeArgument.js        |   1 +
 .../reference/superWithTypeArgument2.js       |   1 +
 .../reference/superWithTypeArgument3.js       |   1 +
 ...side-object-literal-getters-and-setters.js |   3 +-
 tests/baselines/reference/switchStatements.js |   3 +-
 .../reference/systemModuleWithSuperClass.js   |   3 +-
 .../reference/targetTypeBaseCalls.js          |   3 +-
 .../reference/thisInInvalidContexts.js        |   9 +-
 .../thisInInvalidContextsExternalModule.js    |   9 +-
 tests/baselines/reference/thisInSuperCall.js  |   9 +-
 tests/baselines/reference/thisInSuperCall1.js |   3 +-
 tests/baselines/reference/thisInSuperCall2.js |   6 +-
 tests/baselines/reference/thisInSuperCall3.js |   3 +-
 .../reference/thisTypeInFunctions.js          |   9 +-
 .../reference/thisTypeInFunctionsNegative.js  |   6 +-
 .../baselines/reference/tsxDynamicTagName5.js |   3 +-
 .../baselines/reference/tsxDynamicTagName7.js |   3 +-
 .../baselines/reference/tsxDynamicTagName8.js |   3 +-
 .../baselines/reference/tsxDynamicTagName9.js |   3 +-
 .../reference/tsxExternalModuleEmit1.js       |   6 +-
 .../tsxStatelessFunctionComponents2.js        |   3 +-
 .../reference/tsxUnionTypeComponent1.js       |   6 +-
 tests/baselines/reference/typeAssertions.js   |   3 +-
 .../baselines/reference/typeGuardFunction.js  |   3 +-
 .../reference/typeGuardFunctionErrors.js      |   3 +-
 .../reference/typeGuardFunctionGenerics.js    |   3 +-
 .../reference/typeGuardFunctionOfFormThis.js  |  18 ++-
 .../typeGuardFunctionOfFormThisErrors.js      |   6 +-
 .../reference/typeGuardOfFormInstanceOf.js    |   3 +-
 .../reference/typeGuardOfFormIsType.js        |   3 +-
 .../reference/typeGuardOfFormThisMember.js    |   6 +-
 .../typeGuardOfFormThisMemberErrors.js        |   6 +-
 tests/baselines/reference/typeMatch2.js       |   3 +-
 tests/baselines/reference/typeOfSuperCall.js  |   3 +-
 .../reference/typeParameterAsBaseClass.js     |   3 +-
 .../reference/typeParameterAsBaseType.js      |   6 +-
 .../reference/typeParameterExtendingUnion1.js |   6 +-
 .../reference/typeParameterExtendingUnion2.js |   6 +-
 .../baselines/reference/typeRelationships.js  |   3 +-
 .../baselines/reference/typeValueConflict1.js |   3 +-
 .../baselines/reference/typeValueConflict2.js |   6 +-
 tests/baselines/reference/typeofClass2.js     |   3 +-
 .../typesWithSpecializedCallSignatures.js     |   6 +-
 ...typesWithSpecializedConstructSignatures.js |   6 +-
 tests/baselines/reference/undeclaredBase.js   |   3 +-
 .../undefinedIsSubtypeOfEverything.js         |  66 +++++---
 .../baselines/reference/underscoreMapFirst.js |   3 +-
 .../reference/unionTypeEquivalence.js         |   3 +-
 .../reference/unionTypeFromArrayLiteral.js    |   6 +-
 .../reference/unionTypesAssignability.js      |   6 +-
 tests/baselines/reference/unknownSymbols1.js  |   3 +-
 .../reference/unspecializedConstraints.js     |  12 +-
 ...untypedFunctionCallsWithTypeParameters1.js |   3 +-
 .../reference/unusedClassesinNamespace4.js    |   3 +-
 .../unusedIdentifiersConsolidated1.js         |   3 +-
 .../reference/validUseOfThisInSuper.js        |   4 +-
 .../reference/varArgsOnConstructorTypes.js    |   3 +-
 661 files changed, 2983 insertions(+), 1586 deletions(-)

diff --git a/tests/baselines/reference/ExportClassWithAccessibleTypesInTypeParameterConstraintsClassHeritageListMemberTypeAnnotations.js b/tests/baselines/reference/ExportClassWithAccessibleTypesInTypeParameterConstraintsClassHeritageListMemberTypeAnnotations.js
index 7dcbfef1d72..de8e08843a2 100644
--- a/tests/baselines/reference/ExportClassWithAccessibleTypesInTypeParameterConstraintsClassHeritageListMemberTypeAnnotations.js
+++ b/tests/baselines/reference/ExportClassWithAccessibleTypesInTypeParameterConstraintsClassHeritageListMemberTypeAnnotations.js
@@ -38,7 +38,8 @@ var A;
     var Point3d = (function (_super) {
         __extends(Point3d, _super);
         function Point3d() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Point3d;
     }(Point));
diff --git a/tests/baselines/reference/ExportClassWithInaccessibleTypeInTypeParameterConstraint.js b/tests/baselines/reference/ExportClassWithInaccessibleTypeInTypeParameterConstraint.js
index 8f175621af4..58c7bd4c3c1 100644
--- a/tests/baselines/reference/ExportClassWithInaccessibleTypeInTypeParameterConstraint.js
+++ b/tests/baselines/reference/ExportClassWithInaccessibleTypeInTypeParameterConstraint.js
@@ -41,7 +41,8 @@ var A;
     var Point3d = (function (_super) {
         __extends(Point3d, _super);
         function Point3d() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Point3d;
     }(Point));
diff --git a/tests/baselines/reference/abstractClassInLocalScope.js b/tests/baselines/reference/abstractClassInLocalScope.js
index a49da04c8a1..04407cfc08c 100644
--- a/tests/baselines/reference/abstractClassInLocalScope.js
+++ b/tests/baselines/reference/abstractClassInLocalScope.js
@@ -22,7 +22,8 @@ var __extends = (this && this.__extends) || function (d, b) {
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(A));
diff --git a/tests/baselines/reference/abstractClassInLocalScopeIsAbstract.js b/tests/baselines/reference/abstractClassInLocalScopeIsAbstract.js
index 1f6c1dfdd7a..09109c40675 100644
--- a/tests/baselines/reference/abstractClassInLocalScopeIsAbstract.js
+++ b/tests/baselines/reference/abstractClassInLocalScopeIsAbstract.js
@@ -22,7 +22,8 @@ var __extends = (this && this.__extends) || function (d, b) {
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(A));
diff --git a/tests/baselines/reference/abstractProperty.js b/tests/baselines/reference/abstractProperty.js
index 87b5475111b..803df9f1d56 100644
--- a/tests/baselines/reference/abstractProperty.js
+++ b/tests/baselines/reference/abstractProperty.js
@@ -35,7 +35,8 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.raw = "edge";
         this.ro = "readonly please";
     }
diff --git a/tests/baselines/reference/abstractPropertyNegative.js b/tests/baselines/reference/abstractPropertyNegative.js
index 5fc340c58d0..d6e1ce1813f 100644
--- a/tests/baselines/reference/abstractPropertyNegative.js
+++ b/tests/baselines/reference/abstractPropertyNegative.js
@@ -57,7 +57,8 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.ro = "readonly please";
     }
     Object.defineProperty(C.prototype, "concreteWithNoBody", {
@@ -77,7 +78,8 @@ var WrongTypeProperty = (function () {
 var WrongTypePropertyImpl = (function (_super) {
     __extends(WrongTypePropertyImpl, _super);
     function WrongTypePropertyImpl() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.num = "nope, wrong";
     }
     return WrongTypePropertyImpl;
@@ -90,7 +92,8 @@ var WrongTypeAccessor = (function () {
 var WrongTypeAccessorImpl = (function (_super) {
     __extends(WrongTypeAccessorImpl, _super);
     function WrongTypeAccessorImpl() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Object.defineProperty(WrongTypeAccessorImpl.prototype, "num", {
         get: function () { return "nope, wrong"; },
@@ -102,7 +105,8 @@ var WrongTypeAccessorImpl = (function (_super) {
 var WrongTypeAccessorImpl2 = (function (_super) {
     __extends(WrongTypeAccessorImpl2, _super);
     function WrongTypeAccessorImpl2() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.num = "nope, wrong";
     }
     return WrongTypeAccessorImpl2;
diff --git a/tests/baselines/reference/accessOverriddenBaseClassMember1.js b/tests/baselines/reference/accessOverriddenBaseClassMember1.js
index c04532078e9..d60f260a163 100644
--- a/tests/baselines/reference/accessOverriddenBaseClassMember1.js
+++ b/tests/baselines/reference/accessOverriddenBaseClassMember1.js
@@ -34,7 +34,8 @@ var Point = (function () {
 var ColoredPoint = (function (_super) {
     __extends(ColoredPoint, _super);
     function ColoredPoint(x, y, color) {
-        _super.call(this, x, y);
+        var _this;
+        _this = _super.call(this, x, y) || this;
         this.color = color;
     }
     ColoredPoint.prototype.toString = function () {
diff --git a/tests/baselines/reference/accessors_spec_section-4.5_inference.js b/tests/baselines/reference/accessors_spec_section-4.5_inference.js
index 7294aa1aff7..860d74f5204 100644
--- a/tests/baselines/reference/accessors_spec_section-4.5_inference.js
+++ b/tests/baselines/reference/accessors_spec_section-4.5_inference.js
@@ -38,7 +38,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/aliasUsageInAccessorsOfClass.js b/tests/baselines/reference/aliasUsageInAccessorsOfClass.js
index 905ed9bce0e..d717da94d38 100644
--- a/tests/baselines/reference/aliasUsageInAccessorsOfClass.js
+++ b/tests/baselines/reference/aliasUsageInAccessorsOfClass.js
@@ -46,7 +46,8 @@ var Backbone = require("./aliasUsage1_backbone");
 var VisualizationModel = (function (_super) {
     __extends(VisualizationModel, _super);
     function VisualizationModel() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return VisualizationModel;
 }(Backbone.Model));
diff --git a/tests/baselines/reference/aliasUsageInArray.js b/tests/baselines/reference/aliasUsageInArray.js
index 2d9f7cfed6e..f08363776cc 100644
--- a/tests/baselines/reference/aliasUsageInArray.js
+++ b/tests/baselines/reference/aliasUsageInArray.js
@@ -40,7 +40,8 @@ var Backbone = require("./aliasUsageInArray_backbone");
 var VisualizationModel = (function (_super) {
     __extends(VisualizationModel, _super);
     function VisualizationModel() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return VisualizationModel;
 }(Backbone.Model));
diff --git a/tests/baselines/reference/aliasUsageInFunctionExpression.js b/tests/baselines/reference/aliasUsageInFunctionExpression.js
index 21565dc99fc..06e3e266ee9 100644
--- a/tests/baselines/reference/aliasUsageInFunctionExpression.js
+++ b/tests/baselines/reference/aliasUsageInFunctionExpression.js
@@ -39,7 +39,8 @@ var Backbone = require("./aliasUsageInFunctionExpression_backbone");
 var VisualizationModel = (function (_super) {
     __extends(VisualizationModel, _super);
     function VisualizationModel() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return VisualizationModel;
 }(Backbone.Model));
diff --git a/tests/baselines/reference/aliasUsageInGenericFunction.js b/tests/baselines/reference/aliasUsageInGenericFunction.js
index af24b61cf33..96121364837 100644
--- a/tests/baselines/reference/aliasUsageInGenericFunction.js
+++ b/tests/baselines/reference/aliasUsageInGenericFunction.js
@@ -43,7 +43,8 @@ var Backbone = require("./aliasUsageInGenericFunction_backbone");
 var VisualizationModel = (function (_super) {
     __extends(VisualizationModel, _super);
     function VisualizationModel() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return VisualizationModel;
 }(Backbone.Model));
diff --git a/tests/baselines/reference/aliasUsageInIndexerOfClass.js b/tests/baselines/reference/aliasUsageInIndexerOfClass.js
index 3b21f15777c..bbfe2952594 100644
--- a/tests/baselines/reference/aliasUsageInIndexerOfClass.js
+++ b/tests/baselines/reference/aliasUsageInIndexerOfClass.js
@@ -45,7 +45,8 @@ var Backbone = require("./aliasUsageInIndexerOfClass_backbone");
 var VisualizationModel = (function (_super) {
     __extends(VisualizationModel, _super);
     function VisualizationModel() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return VisualizationModel;
 }(Backbone.Model));
diff --git a/tests/baselines/reference/aliasUsageInObjectLiteral.js b/tests/baselines/reference/aliasUsageInObjectLiteral.js
index b380104b461..3b036f52a9d 100644
--- a/tests/baselines/reference/aliasUsageInObjectLiteral.js
+++ b/tests/baselines/reference/aliasUsageInObjectLiteral.js
@@ -40,7 +40,8 @@ var Backbone = require("./aliasUsageInObjectLiteral_backbone");
 var VisualizationModel = (function (_super) {
     __extends(VisualizationModel, _super);
     function VisualizationModel() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return VisualizationModel;
 }(Backbone.Model));
diff --git a/tests/baselines/reference/aliasUsageInOrExpression.js b/tests/baselines/reference/aliasUsageInOrExpression.js
index 1e9a5420345..4167294e5f2 100644
--- a/tests/baselines/reference/aliasUsageInOrExpression.js
+++ b/tests/baselines/reference/aliasUsageInOrExpression.js
@@ -43,7 +43,8 @@ var Backbone = require("./aliasUsageInOrExpression_backbone");
 var VisualizationModel = (function (_super) {
     __extends(VisualizationModel, _super);
     function VisualizationModel() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return VisualizationModel;
 }(Backbone.Model));
diff --git a/tests/baselines/reference/aliasUsageInTypeArgumentOfExtendsClause.js b/tests/baselines/reference/aliasUsageInTypeArgumentOfExtendsClause.js
index 76b90c01bf0..1893f6586ee 100644
--- a/tests/baselines/reference/aliasUsageInTypeArgumentOfExtendsClause.js
+++ b/tests/baselines/reference/aliasUsageInTypeArgumentOfExtendsClause.js
@@ -43,7 +43,8 @@ var Backbone = require("./aliasUsageInTypeArgumentOfExtendsClause_backbone");
 var VisualizationModel = (function (_super) {
     __extends(VisualizationModel, _super);
     function VisualizationModel() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return VisualizationModel;
 }(Backbone.Model));
@@ -64,7 +65,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.x = moduleA;
     }
     return D;
diff --git a/tests/baselines/reference/aliasUsageInVarAssignment.js b/tests/baselines/reference/aliasUsageInVarAssignment.js
index 7c73fac2d67..0ba5cbbc8d0 100644
--- a/tests/baselines/reference/aliasUsageInVarAssignment.js
+++ b/tests/baselines/reference/aliasUsageInVarAssignment.js
@@ -39,7 +39,8 @@ var Backbone = require("./aliasUsageInVarAssignment_backbone");
 var VisualizationModel = (function (_super) {
     __extends(VisualizationModel, _super);
     function VisualizationModel() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return VisualizationModel;
 }(Backbone.Model));
diff --git a/tests/baselines/reference/ambiguousOverloadResolution.js b/tests/baselines/reference/ambiguousOverloadResolution.js
index 275bbf67602..27e6dd714ba 100644
--- a/tests/baselines/reference/ambiguousOverloadResolution.js
+++ b/tests/baselines/reference/ambiguousOverloadResolution.js
@@ -22,7 +22,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/apparentTypeSubtyping.js b/tests/baselines/reference/apparentTypeSubtyping.js
index 2d04b059a9a..914679c7de2 100644
--- a/tests/baselines/reference/apparentTypeSubtyping.js
+++ b/tests/baselines/reference/apparentTypeSubtyping.js
@@ -38,7 +38,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
@@ -51,7 +52,8 @@ var Base2 = (function () {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Base2));
diff --git a/tests/baselines/reference/apparentTypeSupertype.js b/tests/baselines/reference/apparentTypeSupertype.js
index de1b1ba11bd..01fdb92a24e 100644
--- a/tests/baselines/reference/apparentTypeSupertype.js
+++ b/tests/baselines/reference/apparentTypeSupertype.js
@@ -28,7 +28,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/arrayAssignmentTest1.js b/tests/baselines/reference/arrayAssignmentTest1.js
index e2ca36cbd1d..911df30a423 100644
--- a/tests/baselines/reference/arrayAssignmentTest1.js
+++ b/tests/baselines/reference/arrayAssignmentTest1.js
@@ -101,7 +101,8 @@ var C1 = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     C2.prototype.C2M1 = function () { return null; };
     return C2;
diff --git a/tests/baselines/reference/arrayAssignmentTest2.js b/tests/baselines/reference/arrayAssignmentTest2.js
index a15df1b14b7..aff812247a2 100644
--- a/tests/baselines/reference/arrayAssignmentTest2.js
+++ b/tests/baselines/reference/arrayAssignmentTest2.js
@@ -75,7 +75,8 @@ var C1 = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     C2.prototype.C2M1 = function () { return null; };
     return C2;
diff --git a/tests/baselines/reference/arrayBestCommonTypes.js b/tests/baselines/reference/arrayBestCommonTypes.js
index f45f67a8765..7df39836542 100644
--- a/tests/baselines/reference/arrayBestCommonTypes.js
+++ b/tests/baselines/reference/arrayBestCommonTypes.js
@@ -128,7 +128,8 @@ var EmptyTypes;
     var derived = (function (_super) {
         __extends(derived, _super);
         function derived() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return derived;
     }(base));
@@ -187,7 +188,8 @@ var NonEmptyTypes;
     var derived = (function (_super) {
         __extends(derived, _super);
         function derived() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return derived;
     }(base));
diff --git a/tests/baselines/reference/arrayLiteralTypeInference.js b/tests/baselines/reference/arrayLiteralTypeInference.js
index f54dec83c9c..81155544cab 100644
--- a/tests/baselines/reference/arrayLiteralTypeInference.js
+++ b/tests/baselines/reference/arrayLiteralTypeInference.js
@@ -65,14 +65,16 @@ var Action = (function () {
 var ActionA = (function (_super) {
     __extends(ActionA, _super);
     function ActionA() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return ActionA;
 }(Action));
 var ActionB = (function (_super) {
     __extends(ActionB, _super);
     function ActionB() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return ActionB;
 }(Action));
diff --git a/tests/baselines/reference/arrayLiterals.js b/tests/baselines/reference/arrayLiterals.js
index 4dbf88f8688..53066c70391 100644
--- a/tests/baselines/reference/arrayLiterals.js
+++ b/tests/baselines/reference/arrayLiterals.js
@@ -70,7 +70,8 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived1;
 }(Base));
@@ -78,7 +79,8 @@ var Derived1 = (function (_super) {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/arrayLiteralsWithRecursiveGenerics.js b/tests/baselines/reference/arrayLiteralsWithRecursiveGenerics.js
index c15782a8e20..3c5f4365053 100644
--- a/tests/baselines/reference/arrayLiteralsWithRecursiveGenerics.js
+++ b/tests/baselines/reference/arrayLiteralsWithRecursiveGenerics.js
@@ -39,7 +39,8 @@ var List = (function () {
 var DerivedList = (function (_super) {
     __extends(DerivedList, _super);
     function DerivedList() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return DerivedList;
 }(List));
diff --git a/tests/baselines/reference/arrayOfSubtypeIsAssignableToReadonlyArray.js b/tests/baselines/reference/arrayOfSubtypeIsAssignableToReadonlyArray.js
index 255b52e16c9..aba7a7cbc8c 100644
--- a/tests/baselines/reference/arrayOfSubtypeIsAssignableToReadonlyArray.js
+++ b/tests/baselines/reference/arrayOfSubtypeIsAssignableToReadonlyArray.js
@@ -33,14 +33,16 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(Array));
diff --git a/tests/baselines/reference/arrowFunctionContexts.js b/tests/baselines/reference/arrowFunctionContexts.js
index 73e3be15e11..bfd49be6bbf 100644
--- a/tests/baselines/reference/arrowFunctionContexts.js
+++ b/tests/baselines/reference/arrowFunctionContexts.js
@@ -116,8 +116,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = this;
-        _super.call(this, function () { return _this; });
+        var _this;
+        _this = _super.call(this, function () { return _this; }) || this;
     }
     return Derived;
 }(Base));
@@ -158,8 +158,8 @@ var M2;
     var Derived = (function (_super) {
         __extends(Derived, _super);
         function Derived() {
-            var _this = this;
-            _super.call(this, function () { return _this; });
+            var _this;
+            _this = _super.call(this, function () { return _this; }) || this;
         }
         return Derived;
     }(Base));
diff --git a/tests/baselines/reference/assignmentCompatWithCallSignatures3.js b/tests/baselines/reference/assignmentCompatWithCallSignatures3.js
index 24f95ec61ea..80a9aa9cf14 100644
--- a/tests/baselines/reference/assignmentCompatWithCallSignatures3.js
+++ b/tests/baselines/reference/assignmentCompatWithCallSignatures3.js
@@ -114,21 +114,24 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/assignmentCompatWithCallSignatures4.js b/tests/baselines/reference/assignmentCompatWithCallSignatures4.js
index 43608565039..5932aec049a 100644
--- a/tests/baselines/reference/assignmentCompatWithCallSignatures4.js
+++ b/tests/baselines/reference/assignmentCompatWithCallSignatures4.js
@@ -115,21 +115,24 @@ var Errors;
     var Derived = (function (_super) {
         __extends(Derived, _super);
         function Derived() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Derived;
     }(Base));
     var Derived2 = (function (_super) {
         __extends(Derived2, _super);
         function Derived2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Derived2;
     }(Derived));
     var OtherDerived = (function (_super) {
         __extends(OtherDerived, _super);
         function OtherDerived() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return OtherDerived;
     }(Base));
diff --git a/tests/baselines/reference/assignmentCompatWithCallSignatures5.js b/tests/baselines/reference/assignmentCompatWithCallSignatures5.js
index b3318dd53e8..7ea579d87ed 100644
--- a/tests/baselines/reference/assignmentCompatWithCallSignatures5.js
+++ b/tests/baselines/reference/assignmentCompatWithCallSignatures5.js
@@ -80,21 +80,24 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/assignmentCompatWithCallSignatures6.js b/tests/baselines/reference/assignmentCompatWithCallSignatures6.js
index becbfea57a0..0fb5867836c 100644
--- a/tests/baselines/reference/assignmentCompatWithCallSignatures6.js
+++ b/tests/baselines/reference/assignmentCompatWithCallSignatures6.js
@@ -57,21 +57,24 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/assignmentCompatWithConstructSignatures3.js b/tests/baselines/reference/assignmentCompatWithConstructSignatures3.js
index d062a563a4d..b933425ffb0 100644
--- a/tests/baselines/reference/assignmentCompatWithConstructSignatures3.js
+++ b/tests/baselines/reference/assignmentCompatWithConstructSignatures3.js
@@ -114,21 +114,24 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/assignmentCompatWithConstructSignatures4.js b/tests/baselines/reference/assignmentCompatWithConstructSignatures4.js
index 5744424f878..e407c3acdb0 100644
--- a/tests/baselines/reference/assignmentCompatWithConstructSignatures4.js
+++ b/tests/baselines/reference/assignmentCompatWithConstructSignatures4.js
@@ -115,21 +115,24 @@ var Errors;
     var Derived = (function (_super) {
         __extends(Derived, _super);
         function Derived() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Derived;
     }(Base));
     var Derived2 = (function (_super) {
         __extends(Derived2, _super);
         function Derived2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Derived2;
     }(Derived));
     var OtherDerived = (function (_super) {
         __extends(OtherDerived, _super);
         function OtherDerived() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return OtherDerived;
     }(Base));
diff --git a/tests/baselines/reference/assignmentCompatWithConstructSignatures5.js b/tests/baselines/reference/assignmentCompatWithConstructSignatures5.js
index de42671c9f1..59c816dcc5c 100644
--- a/tests/baselines/reference/assignmentCompatWithConstructSignatures5.js
+++ b/tests/baselines/reference/assignmentCompatWithConstructSignatures5.js
@@ -80,21 +80,24 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/assignmentCompatWithConstructSignatures6.js b/tests/baselines/reference/assignmentCompatWithConstructSignatures6.js
index 206ae7768ba..b3b349ebc06 100644
--- a/tests/baselines/reference/assignmentCompatWithConstructSignatures6.js
+++ b/tests/baselines/reference/assignmentCompatWithConstructSignatures6.js
@@ -57,21 +57,24 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/assignmentCompatWithNumericIndexer.js b/tests/baselines/reference/assignmentCompatWithNumericIndexer.js
index 56b206786f1..6e14fb66ecd 100644
--- a/tests/baselines/reference/assignmentCompatWithNumericIndexer.js
+++ b/tests/baselines/reference/assignmentCompatWithNumericIndexer.js
@@ -72,7 +72,8 @@ var Generics;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(A));
diff --git a/tests/baselines/reference/assignmentCompatWithNumericIndexer3.js b/tests/baselines/reference/assignmentCompatWithNumericIndexer3.js
index 53f92dd3b59..3b32f327b07 100644
--- a/tests/baselines/reference/assignmentCompatWithNumericIndexer3.js
+++ b/tests/baselines/reference/assignmentCompatWithNumericIndexer3.js
@@ -59,7 +59,8 @@ b = a; // ok
 var B2 = (function (_super) {
     __extends(B2, _super);
     function B2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B2;
 }(A));
diff --git a/tests/baselines/reference/assignmentCompatWithObjectMembers4.js b/tests/baselines/reference/assignmentCompatWithObjectMembers4.js
index 092de2ca707..ce80efc3c7a 100644
--- a/tests/baselines/reference/assignmentCompatWithObjectMembers4.js
+++ b/tests/baselines/reference/assignmentCompatWithObjectMembers4.js
@@ -108,14 +108,16 @@ var OnlyDerived;
     var Derived = (function (_super) {
         __extends(Derived, _super);
         function Derived() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Derived;
     }(Base));
     var Derived2 = (function (_super) {
         __extends(Derived2, _super);
         function Derived2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Derived2;
     }(Base));
@@ -167,14 +169,16 @@ var WithBase;
     var Derived = (function (_super) {
         __extends(Derived, _super);
         function Derived() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Derived;
     }(Base));
     var Derived2 = (function (_super) {
         __extends(Derived2, _super);
         function Derived2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Derived2;
     }(Base));
diff --git a/tests/baselines/reference/assignmentCompatWithObjectMembersOptionality.js b/tests/baselines/reference/assignmentCompatWithObjectMembersOptionality.js
index 791ae494ab2..d95eb43f0e5 100644
--- a/tests/baselines/reference/assignmentCompatWithObjectMembersOptionality.js
+++ b/tests/baselines/reference/assignmentCompatWithObjectMembersOptionality.js
@@ -103,14 +103,16 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived));
diff --git a/tests/baselines/reference/assignmentCompatWithObjectMembersOptionality2.js b/tests/baselines/reference/assignmentCompatWithObjectMembersOptionality2.js
index d93ddf8b3a4..f4c401979cf 100644
--- a/tests/baselines/reference/assignmentCompatWithObjectMembersOptionality2.js
+++ b/tests/baselines/reference/assignmentCompatWithObjectMembersOptionality2.js
@@ -105,14 +105,16 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived));
diff --git a/tests/baselines/reference/assignmentCompatWithStringIndexer.js b/tests/baselines/reference/assignmentCompatWithStringIndexer.js
index ef6befe268e..54839da4b5a 100644
--- a/tests/baselines/reference/assignmentCompatWithStringIndexer.js
+++ b/tests/baselines/reference/assignmentCompatWithStringIndexer.js
@@ -82,7 +82,8 @@ var Generics;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(A));
@@ -93,7 +94,8 @@ var Generics;
     var B2 = (function (_super) {
         __extends(B2, _super);
         function B2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B2;
     }(A));
diff --git a/tests/baselines/reference/assignmentLHSIsValue.js b/tests/baselines/reference/assignmentLHSIsValue.js
index 8a3b4b35d0b..070c151ee51 100644
--- a/tests/baselines/reference/assignmentLHSIsValue.js
+++ b/tests/baselines/reference/assignmentLHSIsValue.js
@@ -118,7 +118,8 @@ value;
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         _super.prototype. = value;
     }
     Derived.prototype.foo = function () { _super.prototype. = value; };
diff --git a/tests/baselines/reference/asyncImportedPromise_es5.js b/tests/baselines/reference/asyncImportedPromise_es5.js
index 54d1b0fdac8..6fcc24b06bf 100644
--- a/tests/baselines/reference/asyncImportedPromise_es5.js
+++ b/tests/baselines/reference/asyncImportedPromise_es5.js
@@ -19,7 +19,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var Task = (function (_super) {
     __extends(Task, _super);
     function Task() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Task;
 }(Promise));
diff --git a/tests/baselines/reference/asyncMethodWithSuper_es5.js b/tests/baselines/reference/asyncMethodWithSuper_es5.js
index 87debbdc55c..22ca0aa0cbe 100644
--- a/tests/baselines/reference/asyncMethodWithSuper_es5.js
+++ b/tests/baselines/reference/asyncMethodWithSuper_es5.js
@@ -61,7 +61,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     // async method with only call/get on 'super' does not require a binding
     B.prototype.simple = function () {
diff --git a/tests/baselines/reference/asyncQualifiedReturnType_es5.js b/tests/baselines/reference/asyncQualifiedReturnType_es5.js
index 19de38325e2..0081a30d930 100644
--- a/tests/baselines/reference/asyncQualifiedReturnType_es5.js
+++ b/tests/baselines/reference/asyncQualifiedReturnType_es5.js
@@ -13,7 +13,8 @@ var X;
     var MyPromise = (function (_super) {
         __extends(MyPromise, _super);
         function MyPromise() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return MyPromise;
     }(Promise));
diff --git a/tests/baselines/reference/autolift4.js b/tests/baselines/reference/autolift4.js
index e6790021f63..85dd3725639 100644
--- a/tests/baselines/reference/autolift4.js
+++ b/tests/baselines/reference/autolift4.js
@@ -43,7 +43,8 @@ Point.origin = new Point(0, 0);
 var Point3D = (function (_super) {
     __extends(Point3D, _super);
     function Point3D(x, y, z, m) {
-        _super.call(this, x, y);
+        var _this;
+        _this = _super.call(this, x, y) || this;
         this.z = z;
     }
     Point3D.prototype.getDist = function () {
diff --git a/tests/baselines/reference/awaitClassExpression_es5.js b/tests/baselines/reference/awaitClassExpression_es5.js
index 9123f5f2ea8..f81b5800929 100644
--- a/tests/baselines/reference/awaitClassExpression_es5.js
+++ b/tests/baselines/reference/awaitClassExpression_es5.js
@@ -17,7 +17,8 @@ function func() {
                     _a = function (_super) {
                         __extends(D, _super);
                         function D() {
-                            _super.apply(this, arguments);
+                            var _this = _super.apply(this, arguments) || this;
+                            return _this;
                         }
                         return D;
                     };
diff --git a/tests/baselines/reference/baseCheck.js b/tests/baselines/reference/baseCheck.js
index c4210f3f6a5..800742ff63b 100644
--- a/tests/baselines/reference/baseCheck.js
+++ b/tests/baselines/reference/baseCheck.js
@@ -43,14 +43,16 @@ var C = (function () {
 var ELoc = (function (_super) {
     __extends(ELoc, _super);
     function ELoc(x) {
-        _super.call(this, 0, x);
+        var _this;
+        _this = _super.call(this, 0, x) || this;
     }
     return ELoc;
 }(C));
 var ELocVar = (function (_super) {
     __extends(ELocVar, _super);
     function ELocVar(x) {
-        _super.call(this, 0, loc);
+        var _this;
+        _this = _super.call(this, 0, loc) || this;
     }
     ELocVar.prototype.m = function () {
         var loc = 10;
@@ -60,7 +62,8 @@ var ELocVar = (function (_super) {
 var D = (function (_super) {
     __extends(D, _super);
     function D(z) {
-        _super.call(this, this.z);
+        var _this;
+        _this = _super.call(this, this.z) || this;
         this.z = z;
     }
     return D;
@@ -68,7 +71,8 @@ var D = (function (_super) {
 var E = (function (_super) {
     __extends(E, _super);
     function E(z) {
-        _super.call(this, 0, this.z);
+        var _this;
+        _this = _super.call(this, 0, this.z) || this;
         this.z = z;
     }
     return E;
@@ -76,7 +80,8 @@ var E = (function (_super) {
 var F = (function (_super) {
     __extends(F, _super);
     function F(z) {
-        _super.call(this, "hello", this.z);
+        var _this;
+        _this = _super.call(this, "hello", this.z) || this;
         this.z = z;
     }
     return F;
diff --git a/tests/baselines/reference/baseIndexSignatureResolution.js b/tests/baselines/reference/baseIndexSignatureResolution.js
index 3f3fa3cc0b9..6629ef35dda 100644
--- a/tests/baselines/reference/baseIndexSignatureResolution.js
+++ b/tests/baselines/reference/baseIndexSignatureResolution.js
@@ -38,7 +38,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/baseTypeOrderChecking.js b/tests/baselines/reference/baseTypeOrderChecking.js
index 66d2135f01d..187a354553d 100644
--- a/tests/baselines/reference/baseTypeOrderChecking.js
+++ b/tests/baselines/reference/baseTypeOrderChecking.js
@@ -51,7 +51,8 @@ var Class1 = (function () {
 var Class2 = (function (_super) {
     __extends(Class2, _super);
     function Class2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Class2;
 }(Class1));
@@ -63,7 +64,8 @@ var Class3 = (function () {
 var Class4 = (function (_super) {
     __extends(Class4, _super);
     function Class4() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Class4;
 }(Class3));
diff --git a/tests/baselines/reference/baseTypeWrappingInstantiationChain.js b/tests/baselines/reference/baseTypeWrappingInstantiationChain.js
index dc52eeeaee6..bbf57046a97 100644
--- a/tests/baselines/reference/baseTypeWrappingInstantiationChain.js
+++ b/tests/baselines/reference/baseTypeWrappingInstantiationChain.js
@@ -41,7 +41,8 @@ var CBaseBase = (function () {
 var CBase = (function (_super) {
     __extends(CBase, _super);
     function CBase() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return CBase;
 }(CBaseBase));
@@ -59,7 +60,8 @@ var Wrapper = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     C.prototype.works = function () {
         new CBaseBase(this);
diff --git a/tests/baselines/reference/bases.js b/tests/baselines/reference/bases.js
index f67f754d063..fcf1d7fe124 100644
--- a/tests/baselines/reference/bases.js
+++ b/tests/baselines/reference/bases.js
@@ -36,6 +36,7 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
+        var _this;
         this.x;
         any;
     }
diff --git a/tests/baselines/reference/bestCommonTypeOfConditionalExpressions.js b/tests/baselines/reference/bestCommonTypeOfConditionalExpressions.js
index 1c2fc896a6a..a9e38f0520c 100644
--- a/tests/baselines/reference/bestCommonTypeOfConditionalExpressions.js
+++ b/tests/baselines/reference/bestCommonTypeOfConditionalExpressions.js
@@ -44,14 +44,16 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/bestCommonTypeOfConditionalExpressions2.js b/tests/baselines/reference/bestCommonTypeOfConditionalExpressions2.js
index 21a69f517fc..9af685812c2 100644
--- a/tests/baselines/reference/bestCommonTypeOfConditionalExpressions2.js
+++ b/tests/baselines/reference/bestCommonTypeOfConditionalExpressions2.js
@@ -40,14 +40,16 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/bestCommonTypeOfTuple2.js b/tests/baselines/reference/bestCommonTypeOfTuple2.js
index e38ce2854bd..36232ad04b1 100644
--- a/tests/baselines/reference/bestCommonTypeOfTuple2.js
+++ b/tests/baselines/reference/bestCommonTypeOfTuple2.js
@@ -46,7 +46,8 @@ var E = (function () {
 var F = (function (_super) {
     __extends(F, _super);
     function F() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return F;
 }(C));
@@ -59,7 +60,8 @@ var C1 = (function () {
 var D1 = (function (_super) {
     __extends(D1, _super);
     function D1() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.i = "bar";
     }
     return D1;
diff --git a/tests/baselines/reference/callSignatureAssignabilityInInheritance2.js b/tests/baselines/reference/callSignatureAssignabilityInInheritance2.js
index 6b3bf8e125e..4fd0dc2cefc 100644
--- a/tests/baselines/reference/callSignatureAssignabilityInInheritance2.js
+++ b/tests/baselines/reference/callSignatureAssignabilityInInheritance2.js
@@ -84,21 +84,24 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/callSignatureAssignabilityInInheritance3.js b/tests/baselines/reference/callSignatureAssignabilityInInheritance3.js
index a823047fc0d..710725f145b 100644
--- a/tests/baselines/reference/callSignatureAssignabilityInInheritance3.js
+++ b/tests/baselines/reference/callSignatureAssignabilityInInheritance3.js
@@ -131,21 +131,24 @@ var Errors;
     var Derived = (function (_super) {
         __extends(Derived, _super);
         function Derived() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Derived;
     }(Base));
     var Derived2 = (function (_super) {
         __extends(Derived2, _super);
         function Derived2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Derived2;
     }(Derived));
     var OtherDerived = (function (_super) {
         __extends(OtherDerived, _super);
         function OtherDerived() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return OtherDerived;
     }(Base));
diff --git a/tests/baselines/reference/callSignatureAssignabilityInInheritance4.js b/tests/baselines/reference/callSignatureAssignabilityInInheritance4.js
index b60cf2014f1..154aee0693b 100644
--- a/tests/baselines/reference/callSignatureAssignabilityInInheritance4.js
+++ b/tests/baselines/reference/callSignatureAssignabilityInInheritance4.js
@@ -64,21 +64,24 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/callSignatureAssignabilityInInheritance5.js b/tests/baselines/reference/callSignatureAssignabilityInInheritance5.js
index 434af36123e..7359d330cd6 100644
--- a/tests/baselines/reference/callSignatureAssignabilityInInheritance5.js
+++ b/tests/baselines/reference/callSignatureAssignabilityInInheritance5.js
@@ -64,21 +64,24 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/callSignatureAssignabilityInInheritance6.js b/tests/baselines/reference/callSignatureAssignabilityInInheritance6.js
index 9776d14612e..594d2dcafb7 100644
--- a/tests/baselines/reference/callSignatureAssignabilityInInheritance6.js
+++ b/tests/baselines/reference/callSignatureAssignabilityInInheritance6.js
@@ -67,21 +67,24 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/callWithSpread.js b/tests/baselines/reference/callWithSpread.js
index e89e9d9345b..2149db744b0 100644
--- a/tests/baselines/reference/callWithSpread.js
+++ b/tests/baselines/reference/callWithSpread.js
@@ -99,8 +99,9 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.call(this, 1, 2);
-        _super.apply(this, [1, 2].concat(a));
+        var _this;
+        _this = _super.call(this, 1, 2) || this;
+        _this = _super.apply(this, [1, 2].concat(a)) || this;
     }
     D.prototype.foo = function () {
         _super.prototype.foo.call(this, 1, 2);
diff --git a/tests/baselines/reference/captureThisInSuperCall.js b/tests/baselines/reference/captureThisInSuperCall.js
index 791b6f4c979..0c36877d9dc 100644
--- a/tests/baselines/reference/captureThisInSuperCall.js
+++ b/tests/baselines/reference/captureThisInSuperCall.js
@@ -22,8 +22,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = this;
-        _super.call(this, { test: function () { return _this.someMethod(); } });
+        var _this;
+        _this = _super.call(this, { test: function () { return _this.someMethod(); } }) || this;
     }
     B.prototype.someMethod = function () { };
     return B;
diff --git a/tests/baselines/reference/castingTuple.js b/tests/baselines/reference/castingTuple.js
index bcff0938157..426889df7de 100644
--- a/tests/baselines/reference/castingTuple.js
+++ b/tests/baselines/reference/castingTuple.js
@@ -59,7 +59,8 @@ var D = (function () {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return E;
 }(A));
@@ -67,7 +68,8 @@ var E = (function (_super) {
 var F = (function (_super) {
     __extends(F, _super);
     function F() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return F;
 }(A));
diff --git a/tests/baselines/reference/chainedAssignment3.js b/tests/baselines/reference/chainedAssignment3.js
index b4b6330a7cf..71b345a311c 100644
--- a/tests/baselines/reference/chainedAssignment3.js
+++ b/tests/baselines/reference/chainedAssignment3.js
@@ -36,7 +36,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.js b/tests/baselines/reference/chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.js
index c53910e00ac..7c428751b28 100644
--- a/tests/baselines/reference/chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.js
+++ b/tests/baselines/reference/chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.js
@@ -42,14 +42,16 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(B));
diff --git a/tests/baselines/reference/checkForObjectTooStrict.js b/tests/baselines/reference/checkForObjectTooStrict.js
index cdc19a5688d..48825a01a67 100644
--- a/tests/baselines/reference/checkForObjectTooStrict.js
+++ b/tests/baselines/reference/checkForObjectTooStrict.js
@@ -49,14 +49,16 @@ var Foo;
 var Bar = (function (_super) {
     __extends(Bar, _super);
     function Bar() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
     }
     return Bar;
 }(Foo.Object));
 var Baz = (function (_super) {
     __extends(Baz, _super);
     function Baz() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
     }
     return Baz;
 }(Object));
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing1.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing1.js
index cfb5726dac1..dc70f3e8d08 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing1.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing1.js
@@ -24,7 +24,8 @@ var Based = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         this;
         this.x = 10;
         var that = this;
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing2.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing2.js
index afbc15cf912..f1fcdb48dae 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing2.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing2.js
@@ -24,8 +24,9 @@ var Based = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
+        var _this;
         this.x = 100;
-        _super.call(this);
+        _this = _super.call(this) || this;
         this.x = 10;
         var that = this;
     }
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing3.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing3.js
index 7e9c23c1f83..d2ede7d04b1 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing3.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing3.js
@@ -29,13 +29,14 @@ var Based = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
+        var _this;
         var innver = (function () {
             function innver() {
                 this.y = true;
             }
             return innver;
         }());
-        _super.call(this);
+        _this = _super.call(this) || this;
         this.x = 10;
         var that = this;
     }
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing4.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing4.js
index 1257b446ccb..c6eddf4ef48 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing4.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing4.js
@@ -33,7 +33,7 @@ var Based = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = this;
+        var _this;
         (function () {
             _this; // No error
         });
@@ -43,8 +43,8 @@ var Derived = (function (_super) {
         (function () {
             _this; // No error
         })();
-        _super.call(this);
-        _super.call(this);
+        _this = _super.call(this) || this;
+        _this = _super.call(this) || this;
         this.x = 10;
         var that = this;
     }
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing5.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing5.js
index 1889ee998ca..e58d55fd274 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing5.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing5.js
@@ -25,7 +25,8 @@ var Based = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.call(this, this.x);
+        var _this;
+        _this = _super.call(this, this.x) || this;
     }
     return Derived;
 }(Based));
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing6.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing6.js
index 39db4dec174..15fcbff4c89 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing6.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing6.js
@@ -28,9 +28,9 @@ var Base = (function () {
 var Super = (function (_super) {
     __extends(Super, _super);
     function Super() {
-        var _this = this;
+        var _this;
         (function () { return _this; }); // No Error
-        _super.call(this);
+        _this = _super.call(this) || this;
     }
     return Super;
 }(Base));
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing7.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing7.js
index d071c05db5d..0cade04664d 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing7.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing7.js
@@ -23,8 +23,8 @@ var Base = (function () {
 var Super = (function (_super) {
     __extends(Super, _super);
     function Super() {
-        var _this = this;
-        _super.call(this, (function () { return _this; })); // No error
+        var _this;
+        _this = _super.call(this, (function () { return _this; })) || this; // No error
     }
     return Super;
 }(Base));
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing8.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing8.js
index f334cc7f42b..cf0da205d71 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing8.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing8.js
@@ -28,8 +28,9 @@ var Base = (function () {
 var Super = (function (_super) {
     __extends(Super, _super);
     function Super() {
+        var _this;
         var that = this;
-        _super.call(this);
+        _this = _super.call(this) || this;
     }
     return Super;
 }(Base));
diff --git a/tests/baselines/reference/circularImportAlias.js b/tests/baselines/reference/circularImportAlias.js
index 19c156176bf..9d0e7648dcb 100644
--- a/tests/baselines/reference/circularImportAlias.js
+++ b/tests/baselines/reference/circularImportAlias.js
@@ -32,7 +32,8 @@ var B;
     var D = (function (_super) {
         __extends(D, _super);
         function D() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D;
     }(B.a.C));
diff --git a/tests/baselines/reference/circularTypeofWithFunctionModule.js b/tests/baselines/reference/circularTypeofWithFunctionModule.js
index 6ce1dd62fc5..811e86b21ca 100644
--- a/tests/baselines/reference/circularTypeofWithFunctionModule.js
+++ b/tests/baselines/reference/circularTypeofWithFunctionModule.js
@@ -32,7 +32,8 @@ var maker;
     var Bar = (function (_super) {
         __extends(Bar, _super);
         function Bar() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Bar;
     }(Foo));
diff --git a/tests/baselines/reference/classAbstractConstructorAssignability.js b/tests/baselines/reference/classAbstractConstructorAssignability.js
index 5695e6c79d3..8738b43bb3f 100644
--- a/tests/baselines/reference/classAbstractConstructorAssignability.js
+++ b/tests/baselines/reference/classAbstractConstructorAssignability.js
@@ -28,14 +28,16 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(B));
diff --git a/tests/baselines/reference/classAbstractCrashedOnce.js b/tests/baselines/reference/classAbstractCrashedOnce.js
index 46f0a8938c4..02d31377de8 100644
--- a/tests/baselines/reference/classAbstractCrashedOnce.js
+++ b/tests/baselines/reference/classAbstractCrashedOnce.js
@@ -24,7 +24,8 @@ var foo = (function () {
 var bar = (function (_super) {
     __extends(bar, _super);
     function bar() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     bar.prototype.test = function () {
         this.
diff --git a/tests/baselines/reference/classAbstractExtends.js b/tests/baselines/reference/classAbstractExtends.js
index 8d7128cc03d..8ac2cc9de3d 100644
--- a/tests/baselines/reference/classAbstractExtends.js
+++ b/tests/baselines/reference/classAbstractExtends.js
@@ -31,28 +31,32 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(B));
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(B));
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     E.prototype.bar = function () { };
     return E;
diff --git a/tests/baselines/reference/classAbstractFactoryFunction.js b/tests/baselines/reference/classAbstractFactoryFunction.js
index d5b0417f995..4f612e3d9c6 100644
--- a/tests/baselines/reference/classAbstractFactoryFunction.js
+++ b/tests/baselines/reference/classAbstractFactoryFunction.js
@@ -31,7 +31,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/classAbstractGeneric.js b/tests/baselines/reference/classAbstractGeneric.js
index c9409e97466..b76117fddfc 100644
--- a/tests/baselines/reference/classAbstractGeneric.js
+++ b/tests/baselines/reference/classAbstractGeneric.js
@@ -39,28 +39,32 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(A)); // error -- inherits abstract methods
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(A)); // error -- inherits abstract methods
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     E.prototype.foo = function () { return this.t; };
     return E;
@@ -68,7 +72,8 @@ var E = (function (_super) {
 var F = (function (_super) {
     __extends(F, _super);
     function F() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     F.prototype.bar = function (t) { };
     return F;
@@ -76,7 +81,8 @@ var F = (function (_super) {
 var G = (function (_super) {
     __extends(G, _super);
     function G() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     G.prototype.foo = function () { return this.t; };
     G.prototype.bar = function (t) { };
diff --git a/tests/baselines/reference/classAbstractInAModule.js b/tests/baselines/reference/classAbstractInAModule.js
index 17fbf568601..aa66ba540a8 100644
--- a/tests/baselines/reference/classAbstractInAModule.js
+++ b/tests/baselines/reference/classAbstractInAModule.js
@@ -24,7 +24,8 @@ var M;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(A));
diff --git a/tests/baselines/reference/classAbstractInheritance.js b/tests/baselines/reference/classAbstractInheritance.js
index 4d5c804e557..0bd5dab31a9 100644
--- a/tests/baselines/reference/classAbstractInheritance.js
+++ b/tests/baselines/reference/classAbstractInheritance.js
@@ -35,14 +35,16 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(A));
@@ -54,42 +56,48 @@ var AA = (function () {
 var BB = (function (_super) {
     __extends(BB, _super);
     function BB() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return BB;
 }(AA));
 var CC = (function (_super) {
     __extends(CC, _super);
     function CC() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return CC;
 }(AA));
 var DD = (function (_super) {
     __extends(DD, _super);
     function DD() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return DD;
 }(BB));
 var EE = (function (_super) {
     __extends(EE, _super);
     function EE() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return EE;
 }(BB));
 var FF = (function (_super) {
     __extends(FF, _super);
     function FF() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return FF;
 }(CC));
 var GG = (function (_super) {
     __extends(GG, _super);
     function GG() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return GG;
 }(CC));
diff --git a/tests/baselines/reference/classAbstractInstantiations1.js b/tests/baselines/reference/classAbstractInstantiations1.js
index 0263e9e97b3..aef8f58fab2 100644
--- a/tests/baselines/reference/classAbstractInstantiations1.js
+++ b/tests/baselines/reference/classAbstractInstantiations1.js
@@ -41,14 +41,16 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(B));
diff --git a/tests/baselines/reference/classAbstractInstantiations2.js b/tests/baselines/reference/classAbstractInstantiations2.js
index 379e0b18ccc..2e6cd648dc0 100644
--- a/tests/baselines/reference/classAbstractInstantiations2.js
+++ b/tests/baselines/reference/classAbstractInstantiations2.js
@@ -82,21 +82,24 @@ new x; // okay -- undefined behavior at runtime
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(B)); // error -- not declared abstract
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(B)); // okay
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     E.prototype.bar = function () { return 1; };
     return E;
@@ -104,7 +107,8 @@ var E = (function (_super) {
 var F = (function (_super) {
     __extends(F, _super);
     function F() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     F.prototype.bar = function () { return 2; };
     return F;
diff --git a/tests/baselines/reference/classAbstractOverrideWithAbstract.js b/tests/baselines/reference/classAbstractOverrideWithAbstract.js
index d613dd1fe31..5cb07934658 100644
--- a/tests/baselines/reference/classAbstractOverrideWithAbstract.js
+++ b/tests/baselines/reference/classAbstractOverrideWithAbstract.js
@@ -38,7 +38,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
@@ -51,7 +52,8 @@ var AA = (function () {
 var BB = (function (_super) {
     __extends(BB, _super);
     function BB() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     BB.prototype.bar = function () { };
     return BB;
@@ -59,14 +61,16 @@ var BB = (function (_super) {
 var CC = (function (_super) {
     __extends(CC, _super);
     function CC() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return CC;
 }(BB)); // error
 var DD = (function (_super) {
     __extends(DD, _super);
     function DD() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     DD.prototype.foo = function () { };
     return DD;
diff --git a/tests/baselines/reference/classAbstractSuperCalls.js b/tests/baselines/reference/classAbstractSuperCalls.js
index 7ada903974c..44b15710c73 100644
--- a/tests/baselines/reference/classAbstractSuperCalls.js
+++ b/tests/baselines/reference/classAbstractSuperCalls.js
@@ -42,7 +42,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     B.prototype.bar = function () { _super.prototype.foo.call(this); };
     B.prototype.baz = function () { return this.foo; };
@@ -51,7 +52,8 @@ var B = (function (_super) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     C.prototype.foo = function () { return 2; };
     C.prototype.qux = function () { return _super.prototype.foo.call(this) || _super.prototype.foo; }; // 2 errors, foo is abstract
@@ -68,7 +70,8 @@ var AA = (function () {
 var BB = (function (_super) {
     __extends(BB, _super);
     function BB() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return BB;
 }(AA));
diff --git a/tests/baselines/reference/classAbstractUsingAbstractMethod1.js b/tests/baselines/reference/classAbstractUsingAbstractMethod1.js
index 457195f5449..ae6b08e4bca 100644
--- a/tests/baselines/reference/classAbstractUsingAbstractMethod1.js
+++ b/tests/baselines/reference/classAbstractUsingAbstractMethod1.js
@@ -31,7 +31,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     B.prototype.foo = function () { return 1; };
     return B;
@@ -39,7 +40,8 @@ var B = (function (_super) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/classAbstractUsingAbstractMethods2.js b/tests/baselines/reference/classAbstractUsingAbstractMethods2.js
index dc025b11dde..9f43ee1a6b3 100644
--- a/tests/baselines/reference/classAbstractUsingAbstractMethods2.js
+++ b/tests/baselines/reference/classAbstractUsingAbstractMethods2.js
@@ -41,21 +41,24 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(A));
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     D.prototype.foo = function () { };
     return D;
@@ -63,7 +66,8 @@ var D = (function (_super) {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     E.prototype.foo = function () { };
     return E;
@@ -76,21 +80,24 @@ var AA = (function () {
 var BB = (function (_super) {
     __extends(BB, _super);
     function BB() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return BB;
 }(AA));
 var CC = (function (_super) {
     __extends(CC, _super);
     function CC() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return CC;
 }(AA));
 var DD = (function (_super) {
     __extends(DD, _super);
     function DD() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     DD.prototype.foo = function () { };
     return DD;
diff --git a/tests/baselines/reference/classConstructorAccessibility2.js b/tests/baselines/reference/classConstructorAccessibility2.js
index 03b7af3e716..95206681372 100644
--- a/tests/baselines/reference/classConstructorAccessibility2.js
+++ b/tests/baselines/reference/classConstructorAccessibility2.js
@@ -77,7 +77,8 @@ var BaseC = (function () {
 var DerivedA = (function (_super) {
     __extends(DerivedA, _super);
     function DerivedA(x) {
-        _super.call(this, x);
+        var _this;
+        _this = _super.call(this, x) || this;
         this.x = x;
     }
     DerivedA.prototype.createInstance = function () { new DerivedA(5); };
@@ -88,7 +89,8 @@ var DerivedA = (function (_super) {
 var DerivedB = (function (_super) {
     __extends(DerivedB, _super);
     function DerivedB(x) {
-        _super.call(this, x);
+        var _this;
+        _this = _super.call(this, x) || this;
         this.x = x;
     }
     DerivedB.prototype.createInstance = function () { new DerivedB(7); };
@@ -99,7 +101,8 @@ var DerivedB = (function (_super) {
 var DerivedC = (function (_super) {
     __extends(DerivedC, _super);
     function DerivedC(x) {
-        _super.call(this, x);
+        var _this;
+        _this = _super.call(this, x) || this;
         this.x = x;
     }
     DerivedC.prototype.createInstance = function () { new DerivedC(9); };
diff --git a/tests/baselines/reference/classConstructorAccessibility4.js b/tests/baselines/reference/classConstructorAccessibility4.js
index 6342facae21..dfbc70de115 100644
--- a/tests/baselines/reference/classConstructorAccessibility4.js
+++ b/tests/baselines/reference/classConstructorAccessibility4.js
@@ -51,7 +51,8 @@ var A = (function () {
         var C = (function (_super) {
             __extends(C, _super);
             function C() {
-                _super.apply(this, arguments);
+                var _this = _super.apply(this, arguments) || this;
+                return _this;
             }
             return C;
         }(A));
@@ -73,7 +74,8 @@ var D = (function () {
         var F = (function (_super) {
             __extends(F, _super);
             function F() {
-                _super.apply(this, arguments);
+                var _this = _super.apply(this, arguments) || this;
+                return _this;
             }
             return F;
         }(D));
diff --git a/tests/baselines/reference/classConstructorAccessibility5.js b/tests/baselines/reference/classConstructorAccessibility5.js
index ec9e9f83a8e..b73ecb4a92b 100644
--- a/tests/baselines/reference/classConstructorAccessibility5.js
+++ b/tests/baselines/reference/classConstructorAccessibility5.js
@@ -25,7 +25,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived.make = function () { new Base(); }; // ok
     return Derived;
diff --git a/tests/baselines/reference/classConstructorParametersAccessibility.js b/tests/baselines/reference/classConstructorParametersAccessibility.js
index c31fd8bf9dd..1f282ba7132 100644
--- a/tests/baselines/reference/classConstructorParametersAccessibility.js
+++ b/tests/baselines/reference/classConstructorParametersAccessibility.js
@@ -59,7 +59,8 @@ c3.p; // protected, error
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived(p) {
-        _super.call(this, p);
+        var _this;
+        _this = _super.call(this, p) || this;
         this.p; // OK
     }
     return Derived;
diff --git a/tests/baselines/reference/classConstructorParametersAccessibility2.js b/tests/baselines/reference/classConstructorParametersAccessibility2.js
index 7f52a6a581f..81ad696ddc8 100644
--- a/tests/baselines/reference/classConstructorParametersAccessibility2.js
+++ b/tests/baselines/reference/classConstructorParametersAccessibility2.js
@@ -59,7 +59,8 @@ c3.p; // protected, error
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived(p) {
-        _super.call(this, p);
+        var _this;
+        _this = _super.call(this, p) || this;
         this.p; // OK
     }
     return Derived;
diff --git a/tests/baselines/reference/classConstructorParametersAccessibility3.js b/tests/baselines/reference/classConstructorParametersAccessibility3.js
index 0da9449a3a7..95509867cc5 100644
--- a/tests/baselines/reference/classConstructorParametersAccessibility3.js
+++ b/tests/baselines/reference/classConstructorParametersAccessibility3.js
@@ -28,7 +28,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived(p) {
-        _super.call(this, p);
+        var _this;
+        _this = _super.call(this, p) || this;
         this.p = p;
         this.p; // OK
     }
diff --git a/tests/baselines/reference/classDeclarationMergedInModuleWithContinuation.js b/tests/baselines/reference/classDeclarationMergedInModuleWithContinuation.js
index 7ab6cb2ceca..83152355a13 100644
--- a/tests/baselines/reference/classDeclarationMergedInModuleWithContinuation.js
+++ b/tests/baselines/reference/classDeclarationMergedInModuleWithContinuation.js
@@ -35,7 +35,8 @@ var M;
     var O = (function (_super) {
         __extends(O, _super);
         function O() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return O;
     }(M.N));
diff --git a/tests/baselines/reference/classDoesNotDependOnBaseTypes.js b/tests/baselines/reference/classDoesNotDependOnBaseTypes.js
index 5a455edc082..ef584afd6e9 100644
--- a/tests/baselines/reference/classDoesNotDependOnBaseTypes.js
+++ b/tests/baselines/reference/classDoesNotDependOnBaseTypes.js
@@ -31,7 +31,8 @@ var StringTreeCollectionBase = (function () {
 var StringTreeCollection = (function (_super) {
     __extends(StringTreeCollection, _super);
     function StringTreeCollection() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return StringTreeCollection;
 }(StringTreeCollectionBase));
diff --git a/tests/baselines/reference/classExpression2.js b/tests/baselines/reference/classExpression2.js
index ed9497c8729..f7405cfd38a 100644
--- a/tests/baselines/reference/classExpression2.js
+++ b/tests/baselines/reference/classExpression2.js
@@ -16,7 +16,8 @@ var D = (function () {
 var v = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(D));
diff --git a/tests/baselines/reference/classExpression3.js b/tests/baselines/reference/classExpression3.js
index 508dc039387..b91d5413611 100644
--- a/tests/baselines/reference/classExpression3.js
+++ b/tests/baselines/reference/classExpression3.js
@@ -15,14 +15,16 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(class_1, _super);
     function class_1() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.c = 3;
     }
     return class_1;
 }((function (_super) {
     __extends(class_2, _super);
     function class_2() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.b = 2;
     }
     return class_2;
diff --git a/tests/baselines/reference/classExpressionExtendingAbstractClass.js b/tests/baselines/reference/classExpressionExtendingAbstractClass.js
index c4da02cb321..8673e48d65f 100644
--- a/tests/baselines/reference/classExpressionExtendingAbstractClass.js
+++ b/tests/baselines/reference/classExpressionExtendingAbstractClass.js
@@ -22,7 +22,8 @@ var A = (function () {
 var C = (function (_super) {
     __extends(class_1, _super);
     function class_1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return class_1;
 }(A));
diff --git a/tests/baselines/reference/classExtendingBuiltinType.js b/tests/baselines/reference/classExtendingBuiltinType.js
index ace4cf19fee..2a01c1aa8b3 100644
--- a/tests/baselines/reference/classExtendingBuiltinType.js
+++ b/tests/baselines/reference/classExtendingBuiltinType.js
@@ -20,70 +20,80 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C1 = (function (_super) {
     __extends(C1, _super);
     function C1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C1;
 }(Object));
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }(Function));
 var C3 = (function (_super) {
     __extends(C3, _super);
     function C3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C3;
 }(String));
 var C4 = (function (_super) {
     __extends(C4, _super);
     function C4() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C4;
 }(Boolean));
 var C5 = (function (_super) {
     __extends(C5, _super);
     function C5() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C5;
 }(Number));
 var C6 = (function (_super) {
     __extends(C6, _super);
     function C6() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C6;
 }(Date));
 var C7 = (function (_super) {
     __extends(C7, _super);
     function C7() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C7;
 }(RegExp));
 var C8 = (function (_super) {
     __extends(C8, _super);
     function C8() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C8;
 }(Error));
 var C9 = (function (_super) {
     __extends(C9, _super);
     function C9() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C9;
 }(Array));
 var C10 = (function (_super) {
     __extends(C10, _super);
     function C10() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C10;
 }(Array));
diff --git a/tests/baselines/reference/classExtendingClass.js b/tests/baselines/reference/classExtendingClass.js
index 8073271b5ea..4218bfbea98 100644
--- a/tests/baselines/reference/classExtendingClass.js
+++ b/tests/baselines/reference/classExtendingClass.js
@@ -47,7 +47,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(C));
@@ -66,7 +67,8 @@ var C2 = (function () {
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D2;
 }(C2));
diff --git a/tests/baselines/reference/classExtendingClassLikeType.js b/tests/baselines/reference/classExtendingClassLikeType.js
index a41bb14451a..031253a19ad 100644
--- a/tests/baselines/reference/classExtendingClassLikeType.js
+++ b/tests/baselines/reference/classExtendingClassLikeType.js
@@ -68,14 +68,16 @@ var __extends = (this && this.__extends) || function (d, b) {
 var D0 = (function (_super) {
     __extends(D0, _super);
     function D0() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D0;
 }(Base));
 var D1 = (function (_super) {
     __extends(D1, _super);
     function D1() {
-        _super.call(this, "abc", "def");
+        var _this;
+        _this = _super.call(this, "abc", "def") || this;
         this.x = "x";
         this.y = "y";
     }
@@ -84,8 +86,9 @@ var D1 = (function (_super) {
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        _super.call(this, 10);
-        _super.call(this, 10, 20);
+        var _this;
+        _this = _super.call(this, 10) || this;
+        _this = _super.call(this, 10, 20) || this;
         this.x = 1;
         this.y = 2;
     }
@@ -94,7 +97,8 @@ var D2 = (function (_super) {
 var D3 = (function (_super) {
     __extends(D3, _super);
     function D3() {
-        _super.call(this, "abc", 42);
+        var _this;
+        _this = _super.call(this, "abc", 42) || this;
         this.x = "x";
         this.y = 2;
     }
@@ -104,7 +108,8 @@ var D3 = (function (_super) {
 var D4 = (function (_super) {
     __extends(D4, _super);
     function D4() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D4;
 }(getBase()));
@@ -112,7 +117,8 @@ var D4 = (function (_super) {
 var D5 = (function (_super) {
     __extends(D5, _super);
     function D5() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D5;
 }(getBadBase()));
diff --git a/tests/baselines/reference/classExtendingNonConstructor.js b/tests/baselines/reference/classExtendingNonConstructor.js
index c46e3c5ddbe..d33e6b4edef 100644
--- a/tests/baselines/reference/classExtendingNonConstructor.js
+++ b/tests/baselines/reference/classExtendingNonConstructor.js
@@ -27,49 +27,56 @@ function foo() {
 var C1 = (function (_super) {
     __extends(C1, _super);
     function C1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C1;
 }(undefined));
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }(true));
 var C3 = (function (_super) {
     __extends(C3, _super);
     function C3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C3;
 }(false));
 var C4 = (function (_super) {
     __extends(C4, _super);
     function C4() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C4;
 }(42));
 var C5 = (function (_super) {
     __extends(C5, _super);
     function C5() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C5;
 }("hello"));
 var C6 = (function (_super) {
     __extends(C6, _super);
     function C6() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C6;
 }(x));
 var C7 = (function (_super) {
     __extends(C7, _super);
     function C7() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C7;
 }(foo));
diff --git a/tests/baselines/reference/classExtendingNull.js b/tests/baselines/reference/classExtendingNull.js
index fa6f0357b0d..d6188aaf988 100644
--- a/tests/baselines/reference/classExtendingNull.js
+++ b/tests/baselines/reference/classExtendingNull.js
@@ -12,14 +12,16 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C1 = (function (_super) {
     __extends(C1, _super);
     function C1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C1;
 }(null));
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }((null)));
diff --git a/tests/baselines/reference/classExtendingPrimitive.js b/tests/baselines/reference/classExtendingPrimitive.js
index 8ecad9c24a5..c23683470d0 100644
--- a/tests/baselines/reference/classExtendingPrimitive.js
+++ b/tests/baselines/reference/classExtendingPrimitive.js
@@ -24,28 +24,32 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(number));
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }(string));
 var C3 = (function (_super) {
     __extends(C3, _super);
     function C3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C3;
 }(boolean));
 var C4 = (function (_super) {
     __extends(C4, _super);
     function C4() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C4;
 }(Void));
@@ -58,28 +62,32 @@ void {};
 var C5 = (function (_super) {
     __extends(C5, _super);
     function C5() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C5;
 }(Null));
 var C5a = (function (_super) {
     __extends(C5a, _super);
     function C5a() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C5a;
 }(null));
 var C6 = (function (_super) {
     __extends(C6, _super);
     function C6() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C6;
 }(undefined));
 var C7 = (function (_super) {
     __extends(C7, _super);
     function C7() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C7;
 }(Undefined));
@@ -90,7 +98,8 @@ var E;
 var C8 = (function (_super) {
     __extends(C8, _super);
     function C8() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C8;
 }(E));
diff --git a/tests/baselines/reference/classExtendingPrimitive2.js b/tests/baselines/reference/classExtendingPrimitive2.js
index af766977967..072dc8138c7 100644
--- a/tests/baselines/reference/classExtendingPrimitive2.js
+++ b/tests/baselines/reference/classExtendingPrimitive2.js
@@ -20,7 +20,8 @@ void {};
 var C5a = (function (_super) {
     __extends(C5a, _super);
     function C5a() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C5a;
 }(null));
diff --git a/tests/baselines/reference/classExtendingQualifiedName.js b/tests/baselines/reference/classExtendingQualifiedName.js
index 17d888834ec..b5cf4ae1382 100644
--- a/tests/baselines/reference/classExtendingQualifiedName.js
+++ b/tests/baselines/reference/classExtendingQualifiedName.js
@@ -23,7 +23,8 @@ var M;
     var D = (function (_super) {
         __extends(D, _super);
         function D() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D;
     }(M.C));
diff --git a/tests/baselines/reference/classExtendingQualifiedName2.js b/tests/baselines/reference/classExtendingQualifiedName2.js
index 4f1d872e753..d1ee8b48b3a 100644
--- a/tests/baselines/reference/classExtendingQualifiedName2.js
+++ b/tests/baselines/reference/classExtendingQualifiedName2.js
@@ -24,7 +24,8 @@ var M;
     var D = (function (_super) {
         __extends(D, _super);
         function D() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D;
     }(M.C));
diff --git a/tests/baselines/reference/classExtendsAcrossFiles.js b/tests/baselines/reference/classExtendsAcrossFiles.js
index 0805389f268..0dcf4103f49 100644
--- a/tests/baselines/reference/classExtendsAcrossFiles.js
+++ b/tests/baselines/reference/classExtendsAcrossFiles.js
@@ -37,7 +37,8 @@ exports.b = {
         var B = (function (_super) {
             __extends(B, _super);
             function B() {
-                _super.apply(this, arguments);
+                var _this = _super.apply(this, arguments) || this;
+                return _this;
             }
             return B;
         }(A));
@@ -62,7 +63,8 @@ exports.a = {
         var B = (function (_super) {
             __extends(B, _super);
             function B() {
-                _super.apply(this, arguments);
+                var _this = _super.apply(this, arguments) || this;
+                return _this;
             }
             return B;
         }(A));
diff --git a/tests/baselines/reference/classExtendsClauseClassMergedWithModuleNotReferingConstructor.js b/tests/baselines/reference/classExtendsClauseClassMergedWithModuleNotReferingConstructor.js
index 80b4b7c175d..f1a695c0b2a 100644
--- a/tests/baselines/reference/classExtendsClauseClassMergedWithModuleNotReferingConstructor.js
+++ b/tests/baselines/reference/classExtendsClauseClassMergedWithModuleNotReferingConstructor.js
@@ -33,7 +33,8 @@ var Foo;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(A));
diff --git a/tests/baselines/reference/classExtendsClauseClassNotReferringConstructor.js b/tests/baselines/reference/classExtendsClauseClassNotReferringConstructor.js
index 4c593761f00..f754e140d37 100644
--- a/tests/baselines/reference/classExtendsClauseClassNotReferringConstructor.js
+++ b/tests/baselines/reference/classExtendsClauseClassNotReferringConstructor.js
@@ -23,7 +23,8 @@ var Foo;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(A));
diff --git a/tests/baselines/reference/classExtendsEveryObjectType.js b/tests/baselines/reference/classExtendsEveryObjectType.js
index 8b4663ad2cb..584b31b7e8e 100644
--- a/tests/baselines/reference/classExtendsEveryObjectType.js
+++ b/tests/baselines/reference/classExtendsEveryObjectType.js
@@ -25,14 +25,16 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(I)); // error
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }({ foo: string })); // error
@@ -40,7 +42,8 @@ var x;
 var C3 = (function (_super) {
     __extends(C3, _super);
     function C3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C3;
 }(x)); // error
@@ -51,7 +54,8 @@ var M;
 var C4 = (function (_super) {
     __extends(C4, _super);
     function C4() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C4;
 }(M)); // error
@@ -59,14 +63,16 @@ function foo() { }
 var C5 = (function (_super) {
     __extends(C5, _super);
     function C5() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C5;
 }(foo)); // error
 var C6 = (function (_super) {
     __extends(C6, _super);
     function C6() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C6;
 }([])); // error
diff --git a/tests/baselines/reference/classExtendsEveryObjectType2.js b/tests/baselines/reference/classExtendsEveryObjectType2.js
index 6aceb0ffebf..e01e90d512d 100644
--- a/tests/baselines/reference/classExtendsEveryObjectType2.js
+++ b/tests/baselines/reference/classExtendsEveryObjectType2.js
@@ -12,14 +12,16 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }({ foo: string })); // error
 var C6 = (function (_super) {
     __extends(C6, _super);
     function C6() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C6;
 }([])); // error
diff --git a/tests/baselines/reference/classExtendsInterface.js b/tests/baselines/reference/classExtendsInterface.js
index b324f7382d8..7047eaad658 100644
--- a/tests/baselines/reference/classExtendsInterface.js
+++ b/tests/baselines/reference/classExtendsInterface.js
@@ -17,7 +17,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var A = (function (_super) {
     __extends(A, _super);
     function A() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return A;
 }(Comparable));
@@ -29,7 +30,8 @@ var B = (function () {
 var A2 = (function (_super) {
     __extends(A2, _super);
     function A2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return A2;
 }(Comparable2));
diff --git a/tests/baselines/reference/classExtendsInterfaceInExpression.js b/tests/baselines/reference/classExtendsInterfaceInExpression.js
index 69e63f92570..64d519d6952 100644
--- a/tests/baselines/reference/classExtendsInterfaceInExpression.js
+++ b/tests/baselines/reference/classExtendsInterfaceInExpression.js
@@ -20,7 +20,8 @@ function factory(a) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(factory(A)));
diff --git a/tests/baselines/reference/classExtendsInterfaceInModule.js b/tests/baselines/reference/classExtendsInterfaceInModule.js
index 45415488700..ced164bca10 100644
--- a/tests/baselines/reference/classExtendsInterfaceInModule.js
+++ b/tests/baselines/reference/classExtendsInterfaceInModule.js
@@ -24,21 +24,24 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C1 = (function (_super) {
     __extends(C1, _super);
     function C1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C1;
 }(M.I1));
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }(M.I2));
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(Mod.Nested.I));
diff --git a/tests/baselines/reference/classExtendsItself.js b/tests/baselines/reference/classExtendsItself.js
index 279d0ad6899..654cd35c400 100644
--- a/tests/baselines/reference/classExtendsItself.js
+++ b/tests/baselines/reference/classExtendsItself.js
@@ -14,21 +14,24 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(C)); // error
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(D)); // error
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return E;
 }(E)); // error
diff --git a/tests/baselines/reference/classExtendsItselfIndirectly.js b/tests/baselines/reference/classExtendsItselfIndirectly.js
index f8ea40ee69c..ae5852d91f9 100644
--- a/tests/baselines/reference/classExtendsItselfIndirectly.js
+++ b/tests/baselines/reference/classExtendsItselfIndirectly.js
@@ -20,42 +20,48 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(E)); // error
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(C));
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return E;
 }(D));
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }(E2)); // error
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D2;
 }(C2));
 var E2 = (function (_super) {
     __extends(E2, _super);
     function E2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return E2;
 }(D2));
diff --git a/tests/baselines/reference/classExtendsItselfIndirectly2.js b/tests/baselines/reference/classExtendsItselfIndirectly2.js
index 269edb851e9..63eeb5bc178 100644
--- a/tests/baselines/reference/classExtendsItselfIndirectly2.js
+++ b/tests/baselines/reference/classExtendsItselfIndirectly2.js
@@ -31,7 +31,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(N.E)); // error
@@ -40,7 +41,8 @@ var M;
     var D = (function (_super) {
         __extends(D, _super);
         function D() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D;
     }(C));
@@ -51,7 +53,8 @@ var N;
     var E = (function (_super) {
         __extends(E, _super);
         function E() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return E;
     }(M.D));
@@ -62,7 +65,8 @@ var O;
     var C2 = (function (_super) {
         __extends(C2, _super);
         function C2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return C2;
     }(Q.E2)); // error
@@ -71,7 +75,8 @@ var O;
         var D2 = (function (_super) {
             __extends(D2, _super);
             function D2() {
-                _super.apply(this, arguments);
+                var _this = _super.apply(this, arguments) || this;
+                return _this;
             }
             return D2;
         }(C2));
@@ -82,7 +87,8 @@ var O;
         var E2 = (function (_super) {
             __extends(E2, _super);
             function E2() {
-                _super.apply(this, arguments);
+                var _this = _super.apply(this, arguments) || this;
+                return _this;
             }
             return E2;
         }(P.D2));
diff --git a/tests/baselines/reference/classExtendsItselfIndirectly3.js b/tests/baselines/reference/classExtendsItselfIndirectly3.js
index 2d2cf938156..4e67909f2d3 100644
--- a/tests/baselines/reference/classExtendsItselfIndirectly3.js
+++ b/tests/baselines/reference/classExtendsItselfIndirectly3.js
@@ -27,7 +27,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(E)); // error
@@ -40,7 +41,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(C));
@@ -53,7 +55,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return E;
 }(D));
@@ -66,7 +69,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }(E2)); // error
@@ -79,7 +83,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D2;
 }(C2));
@@ -92,7 +97,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var E2 = (function (_super) {
     __extends(E2, _super);
     function E2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return E2;
 }(D2));
diff --git a/tests/baselines/reference/classExtendsMultipleBaseClasses.js b/tests/baselines/reference/classExtendsMultipleBaseClasses.js
index 61db0a41a5c..a185f6cf40a 100644
--- a/tests/baselines/reference/classExtendsMultipleBaseClasses.js
+++ b/tests/baselines/reference/classExtendsMultipleBaseClasses.js
@@ -22,7 +22,8 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/classExtendsNull.js b/tests/baselines/reference/classExtendsNull.js
index afb2be21c68..3ff1c92a56e 100644
--- a/tests/baselines/reference/classExtendsNull.js
+++ b/tests/baselines/reference/classExtendsNull.js
@@ -21,7 +21,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         return Object.create(null);
     }
     return C;
@@ -29,6 +30,7 @@ var C = (function (_super) {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
+        var _this;
         return Object.create(null);
     }
     return D;
diff --git a/tests/baselines/reference/classExtendsShadowedConstructorFunction.js b/tests/baselines/reference/classExtendsShadowedConstructorFunction.js
index ae2f73cadc1..a7f4a4bb9d9 100644
--- a/tests/baselines/reference/classExtendsShadowedConstructorFunction.js
+++ b/tests/baselines/reference/classExtendsShadowedConstructorFunction.js
@@ -25,7 +25,8 @@ var M;
     var D = (function (_super) {
         __extends(D, _super);
         function D() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D;
     }(C));
diff --git a/tests/baselines/reference/classExtendsValidConstructorFunction.js b/tests/baselines/reference/classExtendsValidConstructorFunction.js
index 00cd35693f1..519074358cc 100644
--- a/tests/baselines/reference/classExtendsValidConstructorFunction.js
+++ b/tests/baselines/reference/classExtendsValidConstructorFunction.js
@@ -16,7 +16,8 @@ var x = new foo(); // can be used as a constructor function
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(foo)); // error, cannot extend it though
diff --git a/tests/baselines/reference/classHeritageWithTrailingSeparator.js b/tests/baselines/reference/classHeritageWithTrailingSeparator.js
index 7f85e4e25d7..d3134a97ccd 100644
--- a/tests/baselines/reference/classHeritageWithTrailingSeparator.js
+++ b/tests/baselines/reference/classHeritageWithTrailingSeparator.js
@@ -17,7 +17,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/classImplementsClass2.js b/tests/baselines/reference/classImplementsClass2.js
index 09cdd5c779b..d525fb8a6ad 100644
--- a/tests/baselines/reference/classImplementsClass2.js
+++ b/tests/baselines/reference/classImplementsClass2.js
@@ -33,7 +33,8 @@ var C = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     C2.prototype.foo = function () {
         return 1;
diff --git a/tests/baselines/reference/classImplementsClass3.js b/tests/baselines/reference/classImplementsClass3.js
index b47514b1286..3257e51b5b8 100644
--- a/tests/baselines/reference/classImplementsClass3.js
+++ b/tests/baselines/reference/classImplementsClass3.js
@@ -37,7 +37,8 @@ var C = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }(A));
diff --git a/tests/baselines/reference/classImplementsClass4.js b/tests/baselines/reference/classImplementsClass4.js
index 32ae1ef3e88..f0b8698c64d 100644
--- a/tests/baselines/reference/classImplementsClass4.js
+++ b/tests/baselines/reference/classImplementsClass4.js
@@ -40,7 +40,8 @@ var C = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }(A));
diff --git a/tests/baselines/reference/classImplementsClass5.js b/tests/baselines/reference/classImplementsClass5.js
index 923ac9c9829..bf5d0141a19 100644
--- a/tests/baselines/reference/classImplementsClass5.js
+++ b/tests/baselines/reference/classImplementsClass5.js
@@ -42,7 +42,8 @@ var C = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }(A));
diff --git a/tests/baselines/reference/classImplementsClass6.js b/tests/baselines/reference/classImplementsClass6.js
index a807590749e..f1929cdc798 100644
--- a/tests/baselines/reference/classImplementsClass6.js
+++ b/tests/baselines/reference/classImplementsClass6.js
@@ -47,7 +47,8 @@ var C = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }(A));
diff --git a/tests/baselines/reference/classIndexer3.js b/tests/baselines/reference/classIndexer3.js
index 39fb844613e..ab825abcd31 100644
--- a/tests/baselines/reference/classIndexer3.js
+++ b/tests/baselines/reference/classIndexer3.js
@@ -24,7 +24,8 @@ var C123 = (function () {
 var D123 = (function (_super) {
     __extends(D123, _super);
     function D123() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D123;
 }(C123));
diff --git a/tests/baselines/reference/classInheritence.js b/tests/baselines/reference/classInheritence.js
index e6e7a1eaf42..11b0c5e3ae2 100644
--- a/tests/baselines/reference/classInheritence.js
+++ b/tests/baselines/reference/classInheritence.js
@@ -11,14 +11,16 @@ var __extends = (this && this.__extends) || function (d, b) {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
 var A = (function (_super) {
     __extends(A, _super);
     function A() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return A;
 }(A));
diff --git a/tests/baselines/reference/classIsSubtypeOfBaseType.js b/tests/baselines/reference/classIsSubtypeOfBaseType.js
index b51488dbe1e..6caa97781dd 100644
--- a/tests/baselines/reference/classIsSubtypeOfBaseType.js
+++ b/tests/baselines/reference/classIsSubtypeOfBaseType.js
@@ -29,14 +29,16 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/classOrder2.js b/tests/baselines/reference/classOrder2.js
index ec49320b4be..49b2a428e06 100644
--- a/tests/baselines/reference/classOrder2.js
+++ b/tests/baselines/reference/classOrder2.js
@@ -28,7 +28,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var A = (function (_super) {
     __extends(A, _super);
     function A() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     A.prototype.foo = function () { this.bar(); };
     return A;
diff --git a/tests/baselines/reference/classOrderBug.js b/tests/baselines/reference/classOrderBug.js
index d937197fad5..1381df2797d 100644
--- a/tests/baselines/reference/classOrderBug.js
+++ b/tests/baselines/reference/classOrderBug.js
@@ -35,7 +35,8 @@ var baz = (function () {
 var foo = (function (_super) {
     __extends(foo, _super);
     function foo() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return foo;
 }(baz));
diff --git a/tests/baselines/reference/classSideInheritance1.js b/tests/baselines/reference/classSideInheritance1.js
index 0e3897a4f46..7898ae8a2b2 100644
--- a/tests/baselines/reference/classSideInheritance1.js
+++ b/tests/baselines/reference/classSideInheritance1.js
@@ -33,7 +33,8 @@ var A = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }(A));
diff --git a/tests/baselines/reference/classSideInheritance2.js b/tests/baselines/reference/classSideInheritance2.js
index 72fd4af1eed..c5c506d1af6 100644
--- a/tests/baselines/reference/classSideInheritance2.js
+++ b/tests/baselines/reference/classSideInheritance2.js
@@ -29,7 +29,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var SubText = (function (_super) {
     __extends(SubText, _super);
     function SubText(text, span) {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
     }
     return SubText;
 }(TextBase));
diff --git a/tests/baselines/reference/classSideInheritance3.js b/tests/baselines/reference/classSideInheritance3.js
index b708489c518..d9e4c3f1482 100644
--- a/tests/baselines/reference/classSideInheritance3.js
+++ b/tests/baselines/reference/classSideInheritance3.js
@@ -33,7 +33,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B(x, data) {
-        _super.call(this, x);
+        var _this;
+        _this = _super.call(this, x) || this;
         this.data = data;
     }
     return B;
@@ -41,7 +42,8 @@ var B = (function (_super) {
 var C = (function (_super) {
     __extends(C, _super);
     function C(x) {
-        _super.call(this, x);
+        var _this;
+        _this = _super.call(this, x) || this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/classUpdateTests.js b/tests/baselines/reference/classUpdateTests.js
index 581575d0d46..7b13fa1bf4c 100644
--- a/tests/baselines/reference/classUpdateTests.js
+++ b/tests/baselines/reference/classUpdateTests.js
@@ -157,7 +157,8 @@ var D = (function () {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.p1 = 0;
     }
     return E;
@@ -165,34 +166,38 @@ var E = (function (_super) {
 var F = (function (_super) {
     __extends(F, _super);
     function F() {
+        var _this;
     } // ERROR - super call required
     return F;
 }(E));
 var G = (function (_super) {
     __extends(G, _super);
     function G() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         this.p1 = 0;
     } // NO ERROR
     return G;
 }(D));
 var H = (function () {
     function H() {
-        _super.call(this);
+        _this = _super.call(this) || this;
     } // ERROR - no super call allowed
     return H;
 }());
 var I = (function (_super) {
     __extends(I, _super);
     function I() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
     } // ERROR - no super call allowed
     return I;
 }(Object));
 var J = (function (_super) {
     __extends(J, _super);
     function J(p1) {
-        _super.call(this); // NO ERROR
+        var _this;
+        _this = _super.call(this) || this; // NO ERROR
         this.p1 = p1;
     }
     return J;
@@ -200,16 +205,18 @@ var J = (function (_super) {
 var K = (function (_super) {
     __extends(K, _super);
     function K(p1) {
+        var _this;
         this.p1 = p1;
         var i = 0;
-        _super.call(this);
+        _this = _super.call(this) || this;
     }
     return K;
 }(G));
 var L = (function (_super) {
     __extends(L, _super);
     function L(p1) {
-        _super.call(this); // NO ERROR
+        var _this;
+        _this = _super.call(this) || this; // NO ERROR
         this.p1 = p1;
     }
     return L;
@@ -217,9 +224,10 @@ var L = (function (_super) {
 var M = (function (_super) {
     __extends(M, _super);
     function M(p1) {
+        var _this;
         this.p1 = p1;
         var i = 0;
-        _super.call(this);
+        _this = _super.call(this) || this;
     }
     return M;
 }(G));
diff --git a/tests/baselines/reference/classWithBaseClassButNoConstructor.js b/tests/baselines/reference/classWithBaseClassButNoConstructor.js
index e94a4700506..6ff5ae2ac5b 100644
--- a/tests/baselines/reference/classWithBaseClassButNoConstructor.js
+++ b/tests/baselines/reference/classWithBaseClassButNoConstructor.js
@@ -54,7 +54,8 @@ var Base = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(Base));
@@ -69,7 +70,8 @@ var Base2 = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(Base2));
@@ -80,7 +82,8 @@ var d2 = new D(1); // ok
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D2;
 }(Base2));
@@ -90,7 +93,8 @@ var d4 = new D(1); // ok
 var D3 = (function (_super) {
     __extends(D3, _super);
     function D3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D3;
 }(Base2));
diff --git a/tests/baselines/reference/classWithConstructors.js b/tests/baselines/reference/classWithConstructors.js
index 04dcfa2325c..6bb9387f673 100644
--- a/tests/baselines/reference/classWithConstructors.js
+++ b/tests/baselines/reference/classWithConstructors.js
@@ -75,7 +75,8 @@ var NonGeneric;
     var D = (function (_super) {
         __extends(D, _super);
         function D() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D;
     }(C2));
@@ -103,7 +104,8 @@ var Generics;
     var D = (function (_super) {
         __extends(D, _super);
         function D() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D;
     }(C2));
diff --git a/tests/baselines/reference/classWithProtectedProperty.js b/tests/baselines/reference/classWithProtectedProperty.js
index 2b2e01e59df..fb07eb3d0b2 100644
--- a/tests/baselines/reference/classWithProtectedProperty.js
+++ b/tests/baselines/reference/classWithProtectedProperty.js
@@ -48,7 +48,8 @@ C.g = function () { return ''; };
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     D.prototype.method = function () {
         // No errors
diff --git a/tests/baselines/reference/classWithStaticMembers.js b/tests/baselines/reference/classWithStaticMembers.js
index 327adead6b8..cd23c220231 100644
--- a/tests/baselines/reference/classWithStaticMembers.js
+++ b/tests/baselines/reference/classWithStaticMembers.js
@@ -45,7 +45,8 @@ var r3 = r.foo;
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/classdecl.js b/tests/baselines/reference/classdecl.js
index a8a440fa17d..d4f6bb11ca9 100644
--- a/tests/baselines/reference/classdecl.js
+++ b/tests/baselines/reference/classdecl.js
@@ -136,7 +136,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return b;
 }(a));
@@ -161,7 +162,8 @@ var m2;
         var c = (function (_super) {
             __extends(c, _super);
             function c() {
-                _super.apply(this, arguments);
+                var _this = _super.apply(this, arguments) || this;
+                return _this;
             }
             return c;
         }(b));
@@ -177,7 +179,8 @@ var m2;
 var c = (function (_super) {
     __extends(c, _super);
     function c() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return c;
 }(m1.b));
diff --git a/tests/baselines/reference/clodulesDerivedClasses.js b/tests/baselines/reference/clodulesDerivedClasses.js
index 7e6f26ad591..dbbbe340ba7 100644
--- a/tests/baselines/reference/clodulesDerivedClasses.js
+++ b/tests/baselines/reference/clodulesDerivedClasses.js
@@ -44,7 +44,8 @@ var Shape;
 var Path = (function (_super) {
     __extends(Path, _super);
     function Path() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Path;
 }(Shape));
diff --git a/tests/baselines/reference/collisionSuperAndLocalFunctionInAccessors.js b/tests/baselines/reference/collisionSuperAndLocalFunctionInAccessors.js
index fc64a8012ee..eaf031c2571 100644
--- a/tests/baselines/reference/collisionSuperAndLocalFunctionInAccessors.js
+++ b/tests/baselines/reference/collisionSuperAndLocalFunctionInAccessors.js
@@ -68,7 +68,8 @@ var Foo = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Object.defineProperty(b.prototype, "prop2", {
         get: function () {
@@ -88,7 +89,8 @@ var b = (function (_super) {
 var c = (function (_super) {
     __extends(c, _super);
     function c() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Object.defineProperty(c.prototype, "prop2", {
         get: function () {
diff --git a/tests/baselines/reference/collisionSuperAndLocalFunctionInConstructor.js b/tests/baselines/reference/collisionSuperAndLocalFunctionInConstructor.js
index b6e7cb121d6..b961b8fa4a5 100644
--- a/tests/baselines/reference/collisionSuperAndLocalFunctionInConstructor.js
+++ b/tests/baselines/reference/collisionSuperAndLocalFunctionInConstructor.js
@@ -42,7 +42,8 @@ var Foo = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         function _super() {
         }
     }
@@ -51,7 +52,8 @@ var b = (function (_super) {
 var c = (function (_super) {
     __extends(c, _super);
     function c() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         var x = function () {
             function _super() {
             }
diff --git a/tests/baselines/reference/collisionSuperAndLocalFunctionInMethod.js b/tests/baselines/reference/collisionSuperAndLocalFunctionInMethod.js
index 14b8bf46697..14965b53abd 100644
--- a/tests/baselines/reference/collisionSuperAndLocalFunctionInMethod.js
+++ b/tests/baselines/reference/collisionSuperAndLocalFunctionInMethod.js
@@ -50,7 +50,8 @@ var Foo = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     b.prototype.foo = function () {
         function _super() {
@@ -63,7 +64,8 @@ var b = (function (_super) {
 var c = (function (_super) {
     __extends(c, _super);
     function c() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     c.prototype.foo = function () {
         var x = function () {
diff --git a/tests/baselines/reference/collisionSuperAndLocalFunctionInProperty.js b/tests/baselines/reference/collisionSuperAndLocalFunctionInProperty.js
index 2af7a6a870e..da4175fe5c7 100644
--- a/tests/baselines/reference/collisionSuperAndLocalFunctionInProperty.js
+++ b/tests/baselines/reference/collisionSuperAndLocalFunctionInProperty.js
@@ -40,7 +40,8 @@ var Foo = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.prop2 = {
             doStuff: function () {
                 function _super() {
diff --git a/tests/baselines/reference/collisionSuperAndLocalVarInAccessors.js b/tests/baselines/reference/collisionSuperAndLocalVarInAccessors.js
index 6887a22ae20..55db3a5e625 100644
--- a/tests/baselines/reference/collisionSuperAndLocalVarInAccessors.js
+++ b/tests/baselines/reference/collisionSuperAndLocalVarInAccessors.js
@@ -58,7 +58,8 @@ var Foo = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Object.defineProperty(b.prototype, "prop2", {
         get: function () {
@@ -76,7 +77,8 @@ var b = (function (_super) {
 var c = (function (_super) {
     __extends(c, _super);
     function c() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Object.defineProperty(c.prototype, "prop2", {
         get: function () {
diff --git a/tests/baselines/reference/collisionSuperAndLocalVarInConstructor.js b/tests/baselines/reference/collisionSuperAndLocalVarInConstructor.js
index d3b5e7a2030..b3ef3000762 100644
--- a/tests/baselines/reference/collisionSuperAndLocalVarInConstructor.js
+++ b/tests/baselines/reference/collisionSuperAndLocalVarInConstructor.js
@@ -36,7 +36,8 @@ var Foo = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         var _super = 10; // Should be error 
     }
     return b;
@@ -44,7 +45,8 @@ var b = (function (_super) {
 var c = (function (_super) {
     __extends(c, _super);
     function c() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         var x = function () {
             var _super = 10; // Should be error
         };
diff --git a/tests/baselines/reference/collisionSuperAndLocalVarInMethod.js b/tests/baselines/reference/collisionSuperAndLocalVarInMethod.js
index 4553608756d..c5bb6ebcd01 100644
--- a/tests/baselines/reference/collisionSuperAndLocalVarInMethod.js
+++ b/tests/baselines/reference/collisionSuperAndLocalVarInMethod.js
@@ -36,7 +36,8 @@ var Foo = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     b.prototype.foo = function () {
         var _super = 10; // Should be error 
@@ -46,7 +47,8 @@ var b = (function (_super) {
 var c = (function (_super) {
     __extends(c, _super);
     function c() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     c.prototype.foo = function () {
         var x = function () {
diff --git a/tests/baselines/reference/collisionSuperAndLocalVarInProperty.js b/tests/baselines/reference/collisionSuperAndLocalVarInProperty.js
index df5d812cf54..598bb5b6e85 100644
--- a/tests/baselines/reference/collisionSuperAndLocalVarInProperty.js
+++ b/tests/baselines/reference/collisionSuperAndLocalVarInProperty.js
@@ -38,7 +38,8 @@ var Foo = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.prop2 = {
             doStuff: function () {
                 var _super = 10; // Should be error 
diff --git a/tests/baselines/reference/collisionSuperAndNameResolution.js b/tests/baselines/reference/collisionSuperAndNameResolution.js
index 2db90d8b026..5501b3e2df4 100644
--- a/tests/baselines/reference/collisionSuperAndNameResolution.js
+++ b/tests/baselines/reference/collisionSuperAndNameResolution.js
@@ -27,7 +27,8 @@ var base = (function () {
 var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Foo.prototype.x = function () {
         console.log(_super); // Error as this doesnt not resolve to user defined _super
diff --git a/tests/baselines/reference/collisionSuperAndParameter.js b/tests/baselines/reference/collisionSuperAndParameter.js
index 29b5ad3b496..9909ca512ce 100644
--- a/tests/baselines/reference/collisionSuperAndParameter.js
+++ b/tests/baselines/reference/collisionSuperAndParameter.js
@@ -94,7 +94,8 @@ var Foo = (function () {
 var Foo2 = (function (_super) {
     __extends(Foo2, _super);
     function Foo2(_super) {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         this.prop4 = {
             doStuff: function (_super) {
             }
@@ -123,7 +124,8 @@ var Foo2 = (function (_super) {
 var Foo4 = (function (_super) {
     __extends(Foo4, _super);
     function Foo4(_super) {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
     }
     Foo4.prototype.y = function (_super) {
         var _this = this;
diff --git a/tests/baselines/reference/collisionSuperAndParameter1.js b/tests/baselines/reference/collisionSuperAndParameter1.js
index 517c126ab44..105fe849767 100644
--- a/tests/baselines/reference/collisionSuperAndParameter1.js
+++ b/tests/baselines/reference/collisionSuperAndParameter1.js
@@ -23,7 +23,8 @@ var Foo = (function () {
 var Foo2 = (function (_super) {
     __extends(Foo2, _super);
     function Foo2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Foo2.prototype.x = function () {
         var lambda = function (_super) {
diff --git a/tests/baselines/reference/collisionSuperAndPropertyNameAsConstuctorParameter.js b/tests/baselines/reference/collisionSuperAndPropertyNameAsConstuctorParameter.js
index f94a9fde5f2..6a8dd340a20 100644
--- a/tests/baselines/reference/collisionSuperAndPropertyNameAsConstuctorParameter.js
+++ b/tests/baselines/reference/collisionSuperAndPropertyNameAsConstuctorParameter.js
@@ -44,14 +44,16 @@ var a = (function () {
 var b1 = (function (_super) {
     __extends(b1, _super);
     function b1(_super) {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
     }
     return b1;
 }(a));
 var b2 = (function (_super) {
     __extends(b2, _super);
     function b2(_super) {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         this._super = _super;
     }
     return b2;
@@ -59,14 +61,16 @@ var b2 = (function (_super) {
 var b3 = (function (_super) {
     __extends(b3, _super);
     function b3(_super) {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
     }
     return b3;
 }(a));
 var b4 = (function (_super) {
     __extends(b4, _super);
     function b4(_super) {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         this._super = _super;
     }
     return b4;
diff --git a/tests/baselines/reference/collisionThisExpressionAndLocalVarWithSuperExperssion.js b/tests/baselines/reference/collisionThisExpressionAndLocalVarWithSuperExperssion.js
index c71b0dcf1dd..59b64e4a9ba 100644
--- a/tests/baselines/reference/collisionThisExpressionAndLocalVarWithSuperExperssion.js
+++ b/tests/baselines/reference/collisionThisExpressionAndLocalVarWithSuperExperssion.js
@@ -34,7 +34,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     b.prototype.foo = function () {
         var _this = this;
@@ -46,7 +47,8 @@ var b = (function (_super) {
 var b2 = (function (_super) {
     __extends(b2, _super);
     function b2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     b2.prototype.foo = function () {
         var _this = this;
diff --git a/tests/baselines/reference/commentsInheritance.js b/tests/baselines/reference/commentsInheritance.js
index 42df3cca389..860c0b90e48 100644
--- a/tests/baselines/reference/commentsInheritance.js
+++ b/tests/baselines/reference/commentsInheritance.js
@@ -227,7 +227,8 @@ var c2 = (function () {
 var c3 = (function (_super) {
     __extends(c3, _super);
     function c3() {
-        _super.call(this, 10);
+        var _this;
+        _this = _super.call(this, 10) || this;
     }
     /** c3 f1*/
     c3.prototype.f1 = function () {
@@ -258,7 +259,8 @@ c2_i = c3_i;
 var c4 = (function (_super) {
     __extends(c4, _super);
     function c4() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return c4;
 }(c2));
diff --git a/tests/baselines/reference/comparisonOperatorWithIdenticalObjects.js b/tests/baselines/reference/comparisonOperatorWithIdenticalObjects.js
index 0de25c15013..fb7a811cba3 100644
--- a/tests/baselines/reference/comparisonOperatorWithIdenticalObjects.js
+++ b/tests/baselines/reference/comparisonOperatorWithIdenticalObjects.js
@@ -227,14 +227,16 @@ var Base = (function () {
 var A2 = (function (_super) {
     __extends(A2, _super);
     function A2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return A2;
 }(Base));
 var B2 = (function (_super) {
     __extends(B2, _super);
     function B2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B2;
 }(Base));
diff --git a/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnCallSignature.js b/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnCallSignature.js
index 4185af60dbc..675235ae324 100644
--- a/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnCallSignature.js
+++ b/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnCallSignature.js
@@ -182,7 +182,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnConstructorSignature.js b/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnConstructorSignature.js
index 90c67439773..ceb386b3e14 100644
--- a/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnConstructorSignature.js
+++ b/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnConstructorSignature.js
@@ -182,7 +182,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnIndexSignature.js b/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnIndexSignature.js
index 736b57e08ba..03494b4f88d 100644
--- a/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnIndexSignature.js
+++ b/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnIndexSignature.js
@@ -125,7 +125,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnInstantiatedCallSignature.js b/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnInstantiatedCallSignature.js
index ca7eea70ad6..ee8185802d4 100644
--- a/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnInstantiatedCallSignature.js
+++ b/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnInstantiatedCallSignature.js
@@ -163,7 +163,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnInstantiatedConstructorSignature.js b/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnInstantiatedConstructorSignature.js
index c64e33827c5..5a36f91c7ca 100644
--- a/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnInstantiatedConstructorSignature.js
+++ b/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnInstantiatedConstructorSignature.js
@@ -163,7 +163,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnCallSignature.js b/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnCallSignature.js
index dc7a12eecdc..f23588dcbc5 100644
--- a/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnCallSignature.js
+++ b/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnCallSignature.js
@@ -273,7 +273,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnConstructorSignature.js b/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnConstructorSignature.js
index d4be6df98dd..cc6fe9ce640 100644
--- a/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnConstructorSignature.js
+++ b/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnConstructorSignature.js
@@ -235,7 +235,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnIndexSignature.js b/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnIndexSignature.js
index ee5ad2fbd07..d401defc2ed 100644
--- a/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnIndexSignature.js
+++ b/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnIndexSignature.js
@@ -121,7 +121,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnInstantiatedCallSignature.js b/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnInstantiatedCallSignature.js
index 79e4bfd0bbf..b4b531b8084 100644
--- a/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnInstantiatedCallSignature.js
+++ b/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnInstantiatedCallSignature.js
@@ -178,7 +178,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnInstantiatedConstructorSignature.js b/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnInstantiatedConstructorSignature.js
index 31c0dd3c7c5..69f46e2ccd2 100644
--- a/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnInstantiatedConstructorSignature.js
+++ b/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnInstantiatedConstructorSignature.js
@@ -178,7 +178,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnProperty.js b/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnProperty.js
index 5decd7a21fb..171f21e77fc 100644
--- a/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnProperty.js
+++ b/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnProperty.js
@@ -92,7 +92,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
@@ -114,7 +115,8 @@ var A2 = (function () {
 var B2 = (function (_super) {
     __extends(B2, _super);
     function B2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B2;
 }(A2));
diff --git a/tests/baselines/reference/complexClassRelationships.js b/tests/baselines/reference/complexClassRelationships.js
index 46974055171..523002e5b57 100644
--- a/tests/baselines/reference/complexClassRelationships.js
+++ b/tests/baselines/reference/complexClassRelationships.js
@@ -57,7 +57,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived.createEmpty = function () {
         var item = new Derived();
diff --git a/tests/baselines/reference/complicatedGenericRecursiveBaseClassReference.js b/tests/baselines/reference/complicatedGenericRecursiveBaseClassReference.js
index 3d885d3eef1..1201dcf3d3d 100644
--- a/tests/baselines/reference/complicatedGenericRecursiveBaseClassReference.js
+++ b/tests/baselines/reference/complicatedGenericRecursiveBaseClassReference.js
@@ -14,7 +14,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var S18 = (function (_super) {
     __extends(S18, _super);
     function S18() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return S18;
 }(S18));
diff --git a/tests/baselines/reference/compoundAssignmentLHSIsValue.js b/tests/baselines/reference/compoundAssignmentLHSIsValue.js
index a55c068d4a4..2057d63b38f 100644
--- a/tests/baselines/reference/compoundAssignmentLHSIsValue.js
+++ b/tests/baselines/reference/compoundAssignmentLHSIsValue.js
@@ -197,7 +197,8 @@ value;
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         _super.prototype. *= value;
         _super.prototype. += value;
     }
diff --git a/tests/baselines/reference/compoundExponentiationAssignmentLHSIsValue.js b/tests/baselines/reference/compoundExponentiationAssignmentLHSIsValue.js
index 16500b823b8..ef29163eda6 100644
--- a/tests/baselines/reference/compoundExponentiationAssignmentLHSIsValue.js
+++ b/tests/baselines/reference/compoundExponentiationAssignmentLHSIsValue.js
@@ -139,7 +139,8 @@ _a = Math.pow(['', ''], value), '' = _a[0], '' = _a[1];
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         (_a = _super.prototype). = Math.pow(_a., value);
         var _a;
     }
diff --git a/tests/baselines/reference/computedPropertyNames24_ES5.js b/tests/baselines/reference/computedPropertyNames24_ES5.js
index 24cfe77d93c..00186f40a28 100644
--- a/tests/baselines/reference/computedPropertyNames24_ES5.js
+++ b/tests/baselines/reference/computedPropertyNames24_ES5.js
@@ -25,7 +25,8 @@ var Base = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     C.prototype[_super.bar.call(this)] = function () { };
     return C;
diff --git a/tests/baselines/reference/computedPropertyNames25_ES5.js b/tests/baselines/reference/computedPropertyNames25_ES5.js
index b03dd285ced..afc0e20eca9 100644
--- a/tests/baselines/reference/computedPropertyNames25_ES5.js
+++ b/tests/baselines/reference/computedPropertyNames25_ES5.js
@@ -30,7 +30,8 @@ var Base = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     C.prototype.foo = function () {
         var obj = (_a = {},
diff --git a/tests/baselines/reference/computedPropertyNames26_ES5.js b/tests/baselines/reference/computedPropertyNames26_ES5.js
index 41a20ac6477..6b75da57e9a 100644
--- a/tests/baselines/reference/computedPropertyNames26_ES5.js
+++ b/tests/baselines/reference/computedPropertyNames26_ES5.js
@@ -27,7 +27,8 @@ var Base = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     C.prototype[(_a = {}, _a[_super.bar.call(this)] = 1, _a)[0]] = function () { };
     return C;
diff --git a/tests/baselines/reference/computedPropertyNames27_ES5.js b/tests/baselines/reference/computedPropertyNames27_ES5.js
index bdef47165b1..3c89ecd50c0 100644
--- a/tests/baselines/reference/computedPropertyNames27_ES5.js
+++ b/tests/baselines/reference/computedPropertyNames27_ES5.js
@@ -19,8 +19,9 @@ var Base = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
-    C.prototype[(_super.call(this), "prop")] = function () { };
+    C.prototype[(_this = _super.call(this) || this, "prop")] = function () { };
     return C;
 }(Base));
diff --git a/tests/baselines/reference/computedPropertyNames28_ES5.js b/tests/baselines/reference/computedPropertyNames28_ES5.js
index ed15bbf0145..aaac258504c 100644
--- a/tests/baselines/reference/computedPropertyNames28_ES5.js
+++ b/tests/baselines/reference/computedPropertyNames28_ES5.js
@@ -24,9 +24,10 @@ var Base = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         var obj = (_a = {},
-            _a[(_super.call(this), "prop")] = function () { },
+            _a[(_this = _super.call(this) || this, "prop")] = function () { },
             _a);
         var _a;
     }
diff --git a/tests/baselines/reference/computedPropertyNames30_ES5.js b/tests/baselines/reference/computedPropertyNames30_ES5.js
index a900fd44c67..c31d873ffb9 100644
--- a/tests/baselines/reference/computedPropertyNames30_ES5.js
+++ b/tests/baselines/reference/computedPropertyNames30_ES5.js
@@ -29,13 +29,14 @@ var Base = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         (function () {
             var obj = (_a = {},
                 // Ideally, we would capture this. But the reference is
                 // illegal, and not capturing this is consistent with
                 //treatment of other similar violations.
-                _a[(_super.call(this), "prop")] = function () { },
+                _a[(_this = _super.call(_this) || _this, "prop")] = function () { },
                 _a);
             var _a;
         });
diff --git a/tests/baselines/reference/computedPropertyNames31_ES5.js b/tests/baselines/reference/computedPropertyNames31_ES5.js
index 2e38e2a131f..7b803e9c987 100644
--- a/tests/baselines/reference/computedPropertyNames31_ES5.js
+++ b/tests/baselines/reference/computedPropertyNames31_ES5.js
@@ -32,7 +32,8 @@ var Base = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     C.prototype.foo = function () {
         var _this = this;
diff --git a/tests/baselines/reference/computedPropertyNames43_ES5.js b/tests/baselines/reference/computedPropertyNames43_ES5.js
index c79a4d8d6d1..293d017734e 100644
--- a/tests/baselines/reference/computedPropertyNames43_ES5.js
+++ b/tests/baselines/reference/computedPropertyNames43_ES5.js
@@ -36,7 +36,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Object.defineProperty(D.prototype, "get1", {
         // Computed properties
diff --git a/tests/baselines/reference/computedPropertyNames44_ES5.js b/tests/baselines/reference/computedPropertyNames44_ES5.js
index 78e20a7d6a3..c990298c4ac 100644
--- a/tests/baselines/reference/computedPropertyNames44_ES5.js
+++ b/tests/baselines/reference/computedPropertyNames44_ES5.js
@@ -40,7 +40,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Object.defineProperty(D.prototype, "set1", {
         set: function (p) { },
diff --git a/tests/baselines/reference/computedPropertyNames45_ES5.js b/tests/baselines/reference/computedPropertyNames45_ES5.js
index 9c7482a4713..f5a31fffabb 100644
--- a/tests/baselines/reference/computedPropertyNames45_ES5.js
+++ b/tests/baselines/reference/computedPropertyNames45_ES5.js
@@ -41,7 +41,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Object.defineProperty(D.prototype, "set1", {
         set: function (p) { },
diff --git a/tests/baselines/reference/conditionalOperatorWithIdenticalBCT.js b/tests/baselines/reference/conditionalOperatorWithIdenticalBCT.js
index 3514965f1ce..a6d00d847f3 100644
--- a/tests/baselines/reference/conditionalOperatorWithIdenticalBCT.js
+++ b/tests/baselines/reference/conditionalOperatorWithIdenticalBCT.js
@@ -63,7 +63,8 @@ var X = (function () {
 var A = (function (_super) {
     __extends(A, _super);
     function A() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return A;
 }(X));
@@ -71,7 +72,8 @@ var A = (function (_super) {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(X));
diff --git a/tests/baselines/reference/conditionalOperatorWithoutIdenticalBCT.js b/tests/baselines/reference/conditionalOperatorWithoutIdenticalBCT.js
index 8780c92fc1e..58b050c5ebe 100644
--- a/tests/baselines/reference/conditionalOperatorWithoutIdenticalBCT.js
+++ b/tests/baselines/reference/conditionalOperatorWithoutIdenticalBCT.js
@@ -39,7 +39,8 @@ var X = (function () {
 var A = (function (_super) {
     __extends(A, _super);
     function A() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return A;
 }(X));
@@ -47,7 +48,8 @@ var A = (function (_super) {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(X));
diff --git a/tests/baselines/reference/constantOverloadFunction.js b/tests/baselines/reference/constantOverloadFunction.js
index 09ff39f582e..934c7eceb0e 100644
--- a/tests/baselines/reference/constantOverloadFunction.js
+++ b/tests/baselines/reference/constantOverloadFunction.js
@@ -28,7 +28,8 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived1.prototype.bar = function () { };
     return Derived1;
@@ -36,7 +37,8 @@ var Derived1 = (function (_super) {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived2.prototype.baz = function () { };
     return Derived2;
@@ -44,7 +46,8 @@ var Derived2 = (function (_super) {
 var Derived3 = (function (_super) {
     __extends(Derived3, _super);
     function Derived3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived3.prototype.biz = function () { };
     return Derived3;
diff --git a/tests/baselines/reference/constantOverloadFunctionNoSubtypeError.js b/tests/baselines/reference/constantOverloadFunctionNoSubtypeError.js
index 37c1b1737cd..217cf23f9cb 100644
--- a/tests/baselines/reference/constantOverloadFunctionNoSubtypeError.js
+++ b/tests/baselines/reference/constantOverloadFunctionNoSubtypeError.js
@@ -29,7 +29,8 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived1.prototype.bar = function () { };
     return Derived1;
@@ -37,7 +38,8 @@ var Derived1 = (function (_super) {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived2.prototype.baz = function () { };
     return Derived2;
@@ -45,7 +47,8 @@ var Derived2 = (function (_super) {
 var Derived3 = (function (_super) {
     __extends(Derived3, _super);
     function Derived3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived3.prototype.biz = function () { };
     return Derived3;
diff --git a/tests/baselines/reference/constraintCheckInGenericBaseTypeReference.js b/tests/baselines/reference/constraintCheckInGenericBaseTypeReference.js
index 4fd63cf60d0..511c293d417 100644
--- a/tests/baselines/reference/constraintCheckInGenericBaseTypeReference.js
+++ b/tests/baselines/reference/constraintCheckInGenericBaseTypeReference.js
@@ -40,7 +40,8 @@ var GenericBase = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(GenericBase));
diff --git a/tests/baselines/reference/constructSignatureAssignabilityInInheritance2.js b/tests/baselines/reference/constructSignatureAssignabilityInInheritance2.js
index 88f35f53b17..0e14e958b28 100644
--- a/tests/baselines/reference/constructSignatureAssignabilityInInheritance2.js
+++ b/tests/baselines/reference/constructSignatureAssignabilityInInheritance2.js
@@ -84,21 +84,24 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/constructSignatureAssignabilityInInheritance3.js b/tests/baselines/reference/constructSignatureAssignabilityInInheritance3.js
index 96318a0d616..cb2cadb7698 100644
--- a/tests/baselines/reference/constructSignatureAssignabilityInInheritance3.js
+++ b/tests/baselines/reference/constructSignatureAssignabilityInInheritance3.js
@@ -129,21 +129,24 @@ var Errors;
     var Derived = (function (_super) {
         __extends(Derived, _super);
         function Derived() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Derived;
     }(Base));
     var Derived2 = (function (_super) {
         __extends(Derived2, _super);
         function Derived2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Derived2;
     }(Derived));
     var OtherDerived = (function (_super) {
         __extends(OtherDerived, _super);
         function OtherDerived() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return OtherDerived;
     }(Base));
diff --git a/tests/baselines/reference/constructSignatureAssignabilityInInheritance4.js b/tests/baselines/reference/constructSignatureAssignabilityInInheritance4.js
index 171c4bc6210..25c69839117 100644
--- a/tests/baselines/reference/constructSignatureAssignabilityInInheritance4.js
+++ b/tests/baselines/reference/constructSignatureAssignabilityInInheritance4.js
@@ -74,21 +74,24 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/constructSignatureAssignabilityInInheritance5.js b/tests/baselines/reference/constructSignatureAssignabilityInInheritance5.js
index 26757c43def..dcd972d3a97 100644
--- a/tests/baselines/reference/constructSignatureAssignabilityInInheritance5.js
+++ b/tests/baselines/reference/constructSignatureAssignabilityInInheritance5.js
@@ -64,21 +64,24 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/constructSignatureAssignabilityInInheritance6.js b/tests/baselines/reference/constructSignatureAssignabilityInInheritance6.js
index ae1d0d90445..69fdebe8f5c 100644
--- a/tests/baselines/reference/constructSignatureAssignabilityInInheritance6.js
+++ b/tests/baselines/reference/constructSignatureAssignabilityInInheritance6.js
@@ -67,21 +67,24 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/constructorArgs.js b/tests/baselines/reference/constructorArgs.js
index 1d533506e15..3345708ddaa 100644
--- a/tests/baselines/reference/constructorArgs.js
+++ b/tests/baselines/reference/constructorArgs.js
@@ -29,7 +29,8 @@ var Super = (function () {
 var Sub = (function (_super) {
     __extends(Sub, _super);
     function Sub(options) {
-        _super.call(this, options.value);
+        var _this;
+        _this = _super.call(this, options.value) || this;
         this.options = options;
     }
     return Sub;
diff --git a/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType.js b/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType.js
index d06faa80f20..b16721d0acc 100644
--- a/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType.js
+++ b/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType.js
@@ -33,14 +33,16 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType2.js b/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType2.js
index 1c3d6bf16d0..a235e2555f3 100644
--- a/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType2.js
+++ b/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType2.js
@@ -47,7 +47,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived(x) {
-        _super.call(this, x);
+        var _this;
+        _this = _super.call(this, x) || this;
     }
     return Derived;
 }(Base));
@@ -55,7 +56,8 @@ var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     // ok, not enforcing assignability relation on this
     function Derived2(x) {
-        _super.call(this, x);
+        var _this;
+        _this = _super.call(this, x) || this;
         return 1;
     }
     return Derived2;
diff --git a/tests/baselines/reference/constructorHasPrototypeProperty.js b/tests/baselines/reference/constructorHasPrototypeProperty.js
index 960b76f52c4..956e8cd2e0d 100644
--- a/tests/baselines/reference/constructorHasPrototypeProperty.js
+++ b/tests/baselines/reference/constructorHasPrototypeProperty.js
@@ -47,7 +47,8 @@ var NonGeneric;
     var D = (function (_super) {
         __extends(D, _super);
         function D() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D;
     }(C));
@@ -66,7 +67,8 @@ var Generic;
     var D = (function (_super) {
         __extends(D, _super);
         function D() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D;
     }(C));
diff --git a/tests/baselines/reference/constructorOverloads2.js b/tests/baselines/reference/constructorOverloads2.js
index 76481ec1bc6..a0ed6d890d4 100644
--- a/tests/baselines/reference/constructorOverloads2.js
+++ b/tests/baselines/reference/constructorOverloads2.js
@@ -40,7 +40,8 @@ var FooBase = (function () {
 var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo(x, y) {
-        _super.call(this, x);
+        var _this;
+        _this = _super.call(this, x) || this;
     }
     Foo.prototype.bar1 = function () { };
     return Foo;
diff --git a/tests/baselines/reference/constructorOverloads3.js b/tests/baselines/reference/constructorOverloads3.js
index 61f0d50db03..7bc7989f7a3 100644
--- a/tests/baselines/reference/constructorOverloads3.js
+++ b/tests/baselines/reference/constructorOverloads3.js
@@ -31,6 +31,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo(x, y) {
+        var _this;
     }
     Foo.prototype.bar1 = function () { };
     return Foo;
diff --git a/tests/baselines/reference/constructorWithIncompleteTypeAnnotation.js b/tests/baselines/reference/constructorWithIncompleteTypeAnnotation.js
index 905c12e07e3..1b91e8a131a 100644
--- a/tests/baselines/reference/constructorWithIncompleteTypeAnnotation.js
+++ b/tests/baselines/reference/constructorWithIncompleteTypeAnnotation.js
@@ -525,7 +525,8 @@ method2();
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     B.prototype.method2 = function () {
         return this.method1(2);
diff --git a/tests/baselines/reference/contextualTypingArrayOfLambdas.js b/tests/baselines/reference/contextualTypingArrayOfLambdas.js
index 5775e0f064d..365e17afc9b 100644
--- a/tests/baselines/reference/contextualTypingArrayOfLambdas.js
+++ b/tests/baselines/reference/contextualTypingArrayOfLambdas.js
@@ -28,14 +28,16 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/contextualTypingOfConditionalExpression.js b/tests/baselines/reference/contextualTypingOfConditionalExpression.js
index 29bb48e7970..7be8079cfd9 100644
--- a/tests/baselines/reference/contextualTypingOfConditionalExpression.js
+++ b/tests/baselines/reference/contextualTypingOfConditionalExpression.js
@@ -29,14 +29,16 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/contextualTypingOfConditionalExpression2.js b/tests/baselines/reference/contextualTypingOfConditionalExpression2.js
index 1d84d74e590..102562a841a 100644
--- a/tests/baselines/reference/contextualTypingOfConditionalExpression2.js
+++ b/tests/baselines/reference/contextualTypingOfConditionalExpression2.js
@@ -26,14 +26,16 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/crashInsourcePropertyIsRelatableToTargetProperty.js b/tests/baselines/reference/crashInsourcePropertyIsRelatableToTargetProperty.js
index c385eff83d5..5fafe95c1a8 100644
--- a/tests/baselines/reference/crashInsourcePropertyIsRelatableToTargetProperty.js
+++ b/tests/baselines/reference/crashInsourcePropertyIsRelatableToTargetProperty.js
@@ -25,7 +25,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/declFileClassExtendsNull.js b/tests/baselines/reference/declFileClassExtendsNull.js
index e9081acab55..58bff801774 100644
--- a/tests/baselines/reference/declFileClassExtendsNull.js
+++ b/tests/baselines/reference/declFileClassExtendsNull.js
@@ -12,7 +12,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var ExtendsNull = (function (_super) {
     __extends(ExtendsNull, _super);
     function ExtendsNull() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return ExtendsNull;
 }(null));
diff --git a/tests/baselines/reference/declFileForFunctionTypeAsTypeParameter.js b/tests/baselines/reference/declFileForFunctionTypeAsTypeParameter.js
index 4b9535cd2c3..d58dcd1f536 100644
--- a/tests/baselines/reference/declFileForFunctionTypeAsTypeParameter.js
+++ b/tests/baselines/reference/declFileForFunctionTypeAsTypeParameter.js
@@ -23,7 +23,8 @@ var X = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(X));
diff --git a/tests/baselines/reference/declFileGenericClassWithGenericExtendedClass.js b/tests/baselines/reference/declFileGenericClassWithGenericExtendedClass.js
index 117bb6a7bd5..2f68300a4bf 100644
--- a/tests/baselines/reference/declFileGenericClassWithGenericExtendedClass.js
+++ b/tests/baselines/reference/declFileGenericClassWithGenericExtendedClass.js
@@ -26,7 +26,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/declFileGenericType.js b/tests/baselines/reference/declFileGenericType.js
index 0974f9d7b36..2ed404342d7 100644
--- a/tests/baselines/reference/declFileGenericType.js
+++ b/tests/baselines/reference/declFileGenericType.js
@@ -91,7 +91,8 @@ exports.g = C.F5();
 var h = (function (_super) {
     __extends(h, _super);
     function h() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return h;
 }(C.A));
diff --git a/tests/baselines/reference/declFileGenericType2.js b/tests/baselines/reference/declFileGenericType2.js
index a4636d82993..4ccc090f4f2 100644
--- a/tests/baselines/reference/declFileGenericType2.js
+++ b/tests/baselines/reference/declFileGenericType2.js
@@ -58,7 +58,8 @@ var templa;
             var AbstractElementController = (function (_super) {
                 __extends(AbstractElementController, _super);
                 function AbstractElementController() {
-                    _super.call(this);
+                    var _this;
+                    _this = _super.call(this) || this;
                 }
                 return AbstractElementController;
             }(templa.mvc.AbstractController));
@@ -78,7 +79,8 @@ var templa;
                 var AbstractCompositeElementController = (function (_super) {
                     __extends(AbstractCompositeElementController, _super);
                     function AbstractCompositeElementController() {
-                        _super.call(this);
+                        var _this;
+                        _this = _super.call(this) || this;
                         this._controllers = [];
                     }
                     return AbstractCompositeElementController;
diff --git a/tests/baselines/reference/declFileWithClassNameConflictingWithClassReferredByExtendsClause.js b/tests/baselines/reference/declFileWithClassNameConflictingWithClassReferredByExtendsClause.js
index 4ac08f97a52..c9c569f8676 100644
--- a/tests/baselines/reference/declFileWithClassNameConflictingWithClassReferredByExtendsClause.js
+++ b/tests/baselines/reference/declFileWithClassNameConflictingWithClassReferredByExtendsClause.js
@@ -35,7 +35,8 @@ var X;
             var W = (function (_super) {
                 __extends(W, _super);
                 function W() {
-                    _super.apply(this, arguments);
+                    var _this = _super.apply(this, arguments) || this;
+                    return _this;
                 }
                 return W;
             }(A.B.Base.W));
@@ -54,7 +55,8 @@ var X;
                 var W = (function (_super) {
                     __extends(W, _super);
                     function W() {
-                        _super.apply(this, arguments);
+                        var _this = _super.apply(this, arguments) || this;
+                        return _this;
                     }
                     return W;
                 }(X.Y.base.W));
diff --git a/tests/baselines/reference/declFileWithExtendsClauseThatHasItsContainerNameConflict.js b/tests/baselines/reference/declFileWithExtendsClauseThatHasItsContainerNameConflict.js
index 6dfce6e8e63..3681f9fa859 100644
--- a/tests/baselines/reference/declFileWithExtendsClauseThatHasItsContainerNameConflict.js
+++ b/tests/baselines/reference/declFileWithExtendsClauseThatHasItsContainerNameConflict.js
@@ -45,7 +45,8 @@ var A;
             var ContextMenu = (function (_super) {
                 __extends(ContextMenu, _super);
                 function ContextMenu() {
-                    _super.apply(this, arguments);
+                    var _this = _super.apply(this, arguments) || this;
+                    return _this;
                 }
                 return ContextMenu;
             }(B.EventManager));
diff --git a/tests/baselines/reference/declarationEmitThisPredicates01.js b/tests/baselines/reference/declarationEmitThisPredicates01.js
index d05b5c46dad..0b364e90e45 100644
--- a/tests/baselines/reference/declarationEmitThisPredicates01.js
+++ b/tests/baselines/reference/declarationEmitThisPredicates01.js
@@ -28,7 +28,8 @@ exports.C = C;
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/declarationEmitThisPredicatesWithPrivateName01.js b/tests/baselines/reference/declarationEmitThisPredicatesWithPrivateName01.js
index e34dcc9810f..aea36311add 100644
--- a/tests/baselines/reference/declarationEmitThisPredicatesWithPrivateName01.js
+++ b/tests/baselines/reference/declarationEmitThisPredicatesWithPrivateName01.js
@@ -28,7 +28,8 @@ exports.C = C;
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/declarationEmit_expressionInExtends.js b/tests/baselines/reference/declarationEmit_expressionInExtends.js
index 061042aa34b..9fbb3a4bf63 100644
--- a/tests/baselines/reference/declarationEmit_expressionInExtends.js
+++ b/tests/baselines/reference/declarationEmit_expressionInExtends.js
@@ -29,7 +29,8 @@ var Q = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(x));
diff --git a/tests/baselines/reference/declarationEmit_expressionInExtends2.js b/tests/baselines/reference/declarationEmit_expressionInExtends2.js
index da0478e26d0..d74f9361e28 100644
--- a/tests/baselines/reference/declarationEmit_expressionInExtends2.js
+++ b/tests/baselines/reference/declarationEmit_expressionInExtends2.js
@@ -29,7 +29,8 @@ function getClass(c) {
 var MyClass = (function (_super) {
     __extends(MyClass, _super);
     function MyClass() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return MyClass;
 }(getClass(2)));
diff --git a/tests/baselines/reference/declarationEmit_expressionInExtends3.js b/tests/baselines/reference/declarationEmit_expressionInExtends3.js
index 10ef42d6838..5b7754dff64 100644
--- a/tests/baselines/reference/declarationEmit_expressionInExtends3.js
+++ b/tests/baselines/reference/declarationEmit_expressionInExtends3.js
@@ -70,7 +70,8 @@ function getExportedClass(c) {
 var MyClass = (function (_super) {
     __extends(MyClass, _super);
     function MyClass() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return MyClass;
 }(getLocalClass(undefined)));
@@ -78,7 +79,8 @@ exports.MyClass = MyClass;
 var MyClass2 = (function (_super) {
     __extends(MyClass2, _super);
     function MyClass2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return MyClass2;
 }(getExportedClass(undefined)));
@@ -86,7 +88,8 @@ exports.MyClass2 = MyClass2;
 var MyClass3 = (function (_super) {
     __extends(MyClass3, _super);
     function MyClass3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return MyClass3;
 }(getExportedClass(undefined)));
@@ -94,7 +97,8 @@ exports.MyClass3 = MyClass3;
 var MyClass4 = (function (_super) {
     __extends(MyClass4, _super);
     function MyClass4() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return MyClass4;
 }(getExportedClass(undefined)));
diff --git a/tests/baselines/reference/declarationEmit_expressionInExtends4.js b/tests/baselines/reference/declarationEmit_expressionInExtends4.js
index 39ee7ce1e69..d304422f038 100644
--- a/tests/baselines/reference/declarationEmit_expressionInExtends4.js
+++ b/tests/baselines/reference/declarationEmit_expressionInExtends4.js
@@ -33,21 +33,24 @@ function getSomething() {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(getSomething()));
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }(SomeUndefinedFunction()));
 var C3 = (function (_super) {
     __extends(C3, _super);
     function C3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C3;
 }(SomeUndefinedFunction));
diff --git a/tests/baselines/reference/declarationEmit_nameConflicts3.js b/tests/baselines/reference/declarationEmit_nameConflicts3.js
index f1ea96973b8..81236200ade 100644
--- a/tests/baselines/reference/declarationEmit_nameConflicts3.js
+++ b/tests/baselines/reference/declarationEmit_nameConflicts3.js
@@ -64,7 +64,8 @@ var M;
         var E = (function (_super) {
             __extends(E, _super);
             function E() {
-                _super.apply(this, arguments);
+                var _this = _super.apply(this, arguments) || this;
+                return _this;
             }
             return E;
         }(C));
diff --git a/tests/baselines/reference/declarationEmit_protectedMembers.js b/tests/baselines/reference/declarationEmit_protectedMembers.js
index 192f0647ed6..e118e164dfc 100644
--- a/tests/baselines/reference/declarationEmit_protectedMembers.js
+++ b/tests/baselines/reference/declarationEmit_protectedMembers.js
@@ -88,7 +88,8 @@ var C1 = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     C2.prototype.f = function () {
         return _super.prototype.f.call(this) + this.x;
@@ -102,7 +103,8 @@ var C2 = (function (_super) {
 var C3 = (function (_super) {
     __extends(C3, _super);
     function C3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     C3.prototype.f = function () {
         return _super.prototype.f.call(this);
diff --git a/tests/baselines/reference/declareDottedExtend.js b/tests/baselines/reference/declareDottedExtend.js
index f1e9ea0b4de..f167928087d 100644
--- a/tests/baselines/reference/declareDottedExtend.js
+++ b/tests/baselines/reference/declareDottedExtend.js
@@ -21,14 +21,16 @@ var ab = A.B;
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(ab.C));
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return E;
 }(A.B.C));
diff --git a/tests/baselines/reference/decoratorOnClassConstructor2.js b/tests/baselines/reference/decoratorOnClassConstructor2.js
index 5fc5501c329..d50912fbeac 100644
--- a/tests/baselines/reference/decoratorOnClassConstructor2.js
+++ b/tests/baselines/reference/decoratorOnClassConstructor2.js
@@ -45,7 +45,8 @@ var _0_ts_2 = require("./0.ts");
 var C = (function (_super) {
     __extends(C, _super);
     function C(prop) {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
     }
     return C;
 }(_0_ts_1.base));
diff --git a/tests/baselines/reference/decoratorOnClassConstructor3.js b/tests/baselines/reference/decoratorOnClassConstructor3.js
index 66946fab8bd..6f37ad9dea1 100644
--- a/tests/baselines/reference/decoratorOnClassConstructor3.js
+++ b/tests/baselines/reference/decoratorOnClassConstructor3.js
@@ -48,7 +48,8 @@ var _0_2 = require("./0");
 var C = (function (_super) {
     __extends(C, _super);
     function C(prop) {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
     }
     return C;
 }(_0_1.base));
diff --git a/tests/baselines/reference/decoratorOnClassMethod12.js b/tests/baselines/reference/decoratorOnClassMethod12.js
index 6e9b9763a3a..6d95c696176 100644
--- a/tests/baselines/reference/decoratorOnClassMethod12.js
+++ b/tests/baselines/reference/decoratorOnClassMethod12.js
@@ -32,7 +32,8 @@ var M;
     var C = (function (_super) {
         __extends(C, _super);
         function C() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         C.prototype.method = function () { };
         return C;
diff --git a/tests/baselines/reference/derivedClassConstructorWithoutSuperCall.js b/tests/baselines/reference/derivedClassConstructorWithoutSuperCall.js
index 2e6ac2c7934..75901c708b3 100644
--- a/tests/baselines/reference/derivedClassConstructorWithoutSuperCall.js
+++ b/tests/baselines/reference/derivedClassConstructorWithoutSuperCall.js
@@ -47,6 +47,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
+        var _this;
     }
     return Derived;
 }(Base));
@@ -58,21 +59,24 @@ var Base2 = (function () {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var r2 = function () { return _super.call(this); }; // error for misplaced super call (nested function)
+        var _this;
+        var r2 = function () { return _this = _super.call(_this) || _this; }; // error for misplaced super call (nested function)
     }
     return Derived2;
 }(Base2));
 var Derived3 = (function (_super) {
     __extends(Derived3, _super);
     function Derived3() {
-        var r = function () { _super.call(this); }; // error
+        var _this;
+        var r = function () { _this = _super.call(this) || this; }; // error
     }
     return Derived3;
 }(Base2));
 var Derived4 = (function (_super) {
     __extends(Derived4, _super);
     function Derived4() {
-        var r = _super.call(this); // ok
+        var _this;
+        var r = _this = _super.call(this) || this; // ok
     }
     return Derived4;
 }(Base2));
diff --git a/tests/baselines/reference/derivedClassFunctionOverridesBaseClassAccessor.js b/tests/baselines/reference/derivedClassFunctionOverridesBaseClassAccessor.js
index 7dbb901362f..6dcf8f3fd83 100644
--- a/tests/baselines/reference/derivedClassFunctionOverridesBaseClassAccessor.js
+++ b/tests/baselines/reference/derivedClassFunctionOverridesBaseClassAccessor.js
@@ -38,7 +38,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived.prototype.x = function () {
         return 1;
diff --git a/tests/baselines/reference/derivedClassIncludesInheritedMembers.js b/tests/baselines/reference/derivedClassIncludesInheritedMembers.js
index 0c7a21232e6..2fe5906e746 100644
--- a/tests/baselines/reference/derivedClassIncludesInheritedMembers.js
+++ b/tests/baselines/reference/derivedClassIncludesInheritedMembers.js
@@ -68,7 +68,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
@@ -89,7 +90,8 @@ var Base2 = (function () {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Base2));
diff --git a/tests/baselines/reference/derivedClassOverridesIndexersWithAssignmentCompatibility.js b/tests/baselines/reference/derivedClassOverridesIndexersWithAssignmentCompatibility.js
index a44d4340b8f..dc63ccb21d8 100644
--- a/tests/baselines/reference/derivedClassOverridesIndexersWithAssignmentCompatibility.js
+++ b/tests/baselines/reference/derivedClassOverridesIndexersWithAssignmentCompatibility.js
@@ -32,7 +32,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
@@ -45,7 +46,8 @@ var Base2 = (function () {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Base2));
diff --git a/tests/baselines/reference/derivedClassOverridesPrivateFunction1.js b/tests/baselines/reference/derivedClassOverridesPrivateFunction1.js
index c81c6f048f5..605ad6afa45 100644
--- a/tests/baselines/reference/derivedClassOverridesPrivateFunction1.js
+++ b/tests/baselines/reference/derivedClassOverridesPrivateFunction1.js
@@ -32,7 +32,8 @@ var BaseClass = (function () {
 var DerivedClass = (function (_super) {
     __extends(DerivedClass, _super);
     function DerivedClass() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
     }
     DerivedClass.prototype._init = function () {
     };
diff --git a/tests/baselines/reference/derivedClassOverridesPrivates.js b/tests/baselines/reference/derivedClassOverridesPrivates.js
index cd486152c1c..7ab70d93ff2 100644
--- a/tests/baselines/reference/derivedClassOverridesPrivates.js
+++ b/tests/baselines/reference/derivedClassOverridesPrivates.js
@@ -29,7 +29,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
@@ -41,7 +42,8 @@ var Base2 = (function () {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Base2));
diff --git a/tests/baselines/reference/derivedClassOverridesProtectedMembers.js b/tests/baselines/reference/derivedClassOverridesProtectedMembers.js
index 5b8af9e85bf..d3e3fe5d4c9 100644
--- a/tests/baselines/reference/derivedClassOverridesProtectedMembers.js
+++ b/tests/baselines/reference/derivedClassOverridesProtectedMembers.js
@@ -66,7 +66,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived(a) {
-        _super.call(this, x);
+        var _this;
+        _this = _super.call(this, x) || this;
     }
     Derived.prototype.b = function (a) { };
     Object.defineProperty(Derived.prototype, "c", {
diff --git a/tests/baselines/reference/derivedClassOverridesProtectedMembers2.js b/tests/baselines/reference/derivedClassOverridesProtectedMembers2.js
index 5c7d73d5dfd..1f43469596a 100644
--- a/tests/baselines/reference/derivedClassOverridesProtectedMembers2.js
+++ b/tests/baselines/reference/derivedClassOverridesProtectedMembers2.js
@@ -94,7 +94,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived(a) {
-        _super.call(this, a);
+        var _this;
+        _this = _super.call(this, a) || this;
     }
     Derived.prototype.b = function (a) { };
     Object.defineProperty(Derived.prototype, "c", {
@@ -131,7 +132,8 @@ var Base2 = (function () {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Base2));
diff --git a/tests/baselines/reference/derivedClassOverridesProtectedMembers3.js b/tests/baselines/reference/derivedClassOverridesProtectedMembers3.js
index ebb675a26db..d678f5ce59f 100644
--- a/tests/baselines/reference/derivedClassOverridesProtectedMembers3.js
+++ b/tests/baselines/reference/derivedClassOverridesProtectedMembers3.js
@@ -103,14 +103,16 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1(a) {
-        _super.call(this, a);
+        var _this;
+        _this = _super.call(this, a) || this;
     }
     return Derived1;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2(a) {
-        _super.call(this, a);
+        var _this;
+        _this = _super.call(this, a) || this;
     }
     Derived2.prototype.b = function (a) { };
     return Derived2;
@@ -118,7 +120,8 @@ var Derived2 = (function (_super) {
 var Derived3 = (function (_super) {
     __extends(Derived3, _super);
     function Derived3(a) {
-        _super.call(this, a);
+        var _this;
+        _this = _super.call(this, a) || this;
     }
     Object.defineProperty(Derived3.prototype, "c", {
         get: function () { return x; },
@@ -130,7 +133,8 @@ var Derived3 = (function (_super) {
 var Derived4 = (function (_super) {
     __extends(Derived4, _super);
     function Derived4(a) {
-        _super.call(this, a);
+        var _this;
+        _this = _super.call(this, a) || this;
     }
     Object.defineProperty(Derived4.prototype, "c", {
         set: function (v) { },
@@ -142,21 +146,24 @@ var Derived4 = (function (_super) {
 var Derived5 = (function (_super) {
     __extends(Derived5, _super);
     function Derived5(a) {
-        _super.call(this, a);
+        var _this;
+        _this = _super.call(this, a) || this;
     }
     return Derived5;
 }(Base));
 var Derived6 = (function (_super) {
     __extends(Derived6, _super);
     function Derived6(a) {
-        _super.call(this, a);
+        var _this;
+        _this = _super.call(this, a) || this;
     }
     return Derived6;
 }(Base));
 var Derived7 = (function (_super) {
     __extends(Derived7, _super);
     function Derived7(a) {
-        _super.call(this, a);
+        var _this;
+        _this = _super.call(this, a) || this;
     }
     Derived7.s = function (a) { };
     return Derived7;
@@ -164,7 +171,8 @@ var Derived7 = (function (_super) {
 var Derived8 = (function (_super) {
     __extends(Derived8, _super);
     function Derived8(a) {
-        _super.call(this, a);
+        var _this;
+        _this = _super.call(this, a) || this;
     }
     Object.defineProperty(Derived8, "t", {
         get: function () { return x; },
@@ -176,7 +184,8 @@ var Derived8 = (function (_super) {
 var Derived9 = (function (_super) {
     __extends(Derived9, _super);
     function Derived9(a) {
-        _super.call(this, a);
+        var _this;
+        _this = _super.call(this, a) || this;
     }
     Object.defineProperty(Derived9, "t", {
         set: function (v) { },
@@ -188,7 +197,8 @@ var Derived9 = (function (_super) {
 var Derived10 = (function (_super) {
     __extends(Derived10, _super);
     function Derived10(a) {
-        _super.call(this, a);
+        var _this;
+        _this = _super.call(this, a) || this;
     }
     return Derived10;
 }(Base));
diff --git a/tests/baselines/reference/derivedClassOverridesProtectedMembers4.js b/tests/baselines/reference/derivedClassOverridesProtectedMembers4.js
index b8a15ee8b6c..eeaf80061af 100644
--- a/tests/baselines/reference/derivedClassOverridesProtectedMembers4.js
+++ b/tests/baselines/reference/derivedClassOverridesProtectedMembers4.js
@@ -30,14 +30,16 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived1;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived1));
diff --git a/tests/baselines/reference/derivedClassOverridesPublicMembers.js b/tests/baselines/reference/derivedClassOverridesPublicMembers.js
index b62f0d8f7d3..7839398551d 100644
--- a/tests/baselines/reference/derivedClassOverridesPublicMembers.js
+++ b/tests/baselines/reference/derivedClassOverridesPublicMembers.js
@@ -92,7 +92,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived(a) {
-        _super.call(this, x);
+        var _this;
+        _this = _super.call(this, x) || this;
     }
     Derived.prototype.b = function (a) { };
     Object.defineProperty(Derived.prototype, "c", {
@@ -129,7 +130,8 @@ var Base2 = (function () {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Base2));
diff --git a/tests/baselines/reference/derivedClassOverridesWithoutSubtype.js b/tests/baselines/reference/derivedClassOverridesWithoutSubtype.js
index 147e6edbbb4..f2d8f72edfb 100644
--- a/tests/baselines/reference/derivedClassOverridesWithoutSubtype.js
+++ b/tests/baselines/reference/derivedClassOverridesWithoutSubtype.js
@@ -37,7 +37,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
@@ -49,7 +50,8 @@ var Base2 = (function () {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Base2));
diff --git a/tests/baselines/reference/derivedClassParameterProperties.js b/tests/baselines/reference/derivedClassParameterProperties.js
index 8e5fa82cf0f..f7afd6529c0 100644
--- a/tests/baselines/reference/derivedClassParameterProperties.js
+++ b/tests/baselines/reference/derivedClassParameterProperties.js
@@ -109,24 +109,27 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived(y) {
+        var _this;
         var a = 1;
-        _super.call(this); // ok
+        _this = _super.call(this) || this; // ok
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2(y) {
+        var _this;
         this.y = y;
         var a = 1;
-        _super.call(this); // error
+        _this = _super.call(this) || this; // error
     }
     return Derived2;
 }(Base));
 var Derived3 = (function (_super) {
     __extends(Derived3, _super);
     function Derived3(y) {
-        _super.call(this); // ok
+        var _this;
+        _this = _super.call(this) || this; // ok
         this.y = y;
         var a = 1;
     }
@@ -135,16 +138,18 @@ var Derived3 = (function (_super) {
 var Derived4 = (function (_super) {
     __extends(Derived4, _super);
     function Derived4(y) {
+        var _this;
         this.a = 1;
         var b = 2;
-        _super.call(this); // error
+        _this = _super.call(this) || this; // error
     }
     return Derived4;
 }(Base));
 var Derived5 = (function (_super) {
     __extends(Derived5, _super);
     function Derived5(y) {
-        _super.call(this); // ok
+        var _this;
+        _this = _super.call(this) || this; // ok
         this.a = 1;
         var b = 2;
     }
@@ -153,26 +158,29 @@ var Derived5 = (function (_super) {
 var Derived6 = (function (_super) {
     __extends(Derived6, _super);
     function Derived6(y) {
+        var _this;
         this.a = 1;
         var b = 2;
-        _super.call(this); // error: "super" has to be called before "this" accessing
+        _this = _super.call(this) || this; // error: "super" has to be called before "this" accessing
     }
     return Derived6;
 }(Base));
 var Derived7 = (function (_super) {
     __extends(Derived7, _super);
     function Derived7(y) {
+        var _this;
         this.a = 1;
         this.a = 3;
         this.b = 3;
-        _super.call(this); // error
+        _this = _super.call(this) || this; // error
     }
     return Derived7;
 }(Base));
 var Derived8 = (function (_super) {
     __extends(Derived8, _super);
     function Derived8(y) {
-        _super.call(this); // ok
+        var _this;
+        _this = _super.call(this) || this; // ok
         this.a = 1;
         this.a = 3;
         this.b = 3;
@@ -188,17 +196,19 @@ var Base2 = (function () {
 var Derived9 = (function (_super) {
     __extends(Derived9, _super);
     function Derived9(y) {
+        var _this;
         this.a = 1;
         this.a = 3;
         this.b = 3;
-        _super.call(this); // error
+        _this = _super.call(this) || this; // error
     }
     return Derived9;
 }(Base2));
 var Derived10 = (function (_super) {
     __extends(Derived10, _super);
     function Derived10(y) {
-        _super.call(this); // ok
+        var _this;
+        _this = _super.call(this) || this; // ok
         this.a = 1;
         this.a = 3;
         this.b = 3;
diff --git a/tests/baselines/reference/derivedClassSuperCallsInNonConstructorMembers.js b/tests/baselines/reference/derivedClassSuperCallsInNonConstructorMembers.js
index 50408d3bee7..ad2dc22debf 100644
--- a/tests/baselines/reference/derivedClassSuperCallsInNonConstructorMembers.js
+++ b/tests/baselines/reference/derivedClassSuperCallsInNonConstructorMembers.js
@@ -46,37 +46,38 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
-        this.a = _super.call(this);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
+        this.a = _this = _super.call(this) || this;
     }
     Derived.prototype.b = function () {
-        _super.call(this);
+        _this = _super.call(this) || this;
     };
     Object.defineProperty(Derived.prototype, "C", {
         get: function () {
-            _super.call(this);
+            _this = _super.call(this) || this;
             return 1;
         },
         set: function (v) {
-            _super.call(this);
+            _this = _super.call(this) || this;
         },
         enumerable: true,
         configurable: true
     });
     Derived.b = function () {
-        _super.call(this);
+        _this = _super.call(this) || this;
     };
     Object.defineProperty(Derived, "C", {
         get: function () {
-            _super.call(this);
+            _this = _super.call(this) || this;
             return 1;
         },
         set: function (v) {
-            _super.call(this);
+            _this = _super.call(this) || this;
         },
         enumerable: true,
         configurable: true
     });
     return Derived;
 }(Base));
-Derived.a = _super.call(this);
+Derived.a = _this = _super.call(this) || this;
diff --git a/tests/baselines/reference/derivedClassSuperCallsWithThisArg.js b/tests/baselines/reference/derivedClassSuperCallsWithThisArg.js
index 1c88306bf3a..a464970fe50 100644
--- a/tests/baselines/reference/derivedClassSuperCallsWithThisArg.js
+++ b/tests/baselines/reference/derivedClassSuperCallsWithThisArg.js
@@ -42,14 +42,16 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.call(this, this); // ok
+        var _this;
+        _this = _super.call(this, this) || this; // ok
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2(a) {
-        _super.call(this, this); // error
+        var _this;
+        _this = _super.call(this, this) || this; // error
         this.a = a;
     }
     return Derived2;
@@ -57,8 +59,8 @@ var Derived2 = (function (_super) {
 var Derived3 = (function (_super) {
     __extends(Derived3, _super);
     function Derived3(a) {
-        var _this = this;
-        _super.call(this, function () { return _this; }); // error
+        var _this;
+        _this = _super.call(this, function () { return _this; }) || this; // error
         this.a = a;
     }
     return Derived3;
@@ -66,7 +68,8 @@ var Derived3 = (function (_super) {
 var Derived4 = (function (_super) {
     __extends(Derived4, _super);
     function Derived4(a) {
-        _super.call(this, function () { return this; }); // ok
+        var _this;
+        _this = _super.call(this, function () { return this; }) || this; // ok
         this.a = a;
     }
     return Derived4;
diff --git a/tests/baselines/reference/derivedClassTransitivity.js b/tests/baselines/reference/derivedClassTransitivity.js
index 38c465492e6..0e88d3664c6 100644
--- a/tests/baselines/reference/derivedClassTransitivity.js
+++ b/tests/baselines/reference/derivedClassTransitivity.js
@@ -36,7 +36,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     D.prototype.foo = function () { }; // ok to drop parameters
     return D;
@@ -44,7 +45,8 @@ var D = (function (_super) {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     E.prototype.foo = function (x) { }; // ok to add optional parameters
     return E;
diff --git a/tests/baselines/reference/derivedClassTransitivity2.js b/tests/baselines/reference/derivedClassTransitivity2.js
index 5d08905a605..5a3f8f3cf57 100644
--- a/tests/baselines/reference/derivedClassTransitivity2.js
+++ b/tests/baselines/reference/derivedClassTransitivity2.js
@@ -36,7 +36,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     D.prototype.foo = function (x) { }; // ok to drop parameters
     return D;
@@ -44,7 +45,8 @@ var D = (function (_super) {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     E.prototype.foo = function (x, y) { }; // ok to add optional parameters
     return E;
diff --git a/tests/baselines/reference/derivedClassTransitivity3.js b/tests/baselines/reference/derivedClassTransitivity3.js
index be7e97a8fc5..f6aa6963795 100644
--- a/tests/baselines/reference/derivedClassTransitivity3.js
+++ b/tests/baselines/reference/derivedClassTransitivity3.js
@@ -36,7 +36,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     D.prototype.foo = function (x) { }; // ok to drop parameters
     return D;
@@ -44,7 +45,8 @@ var D = (function (_super) {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     E.prototype.foo = function (x, y) { }; // ok to add optional parameters
     return E;
diff --git a/tests/baselines/reference/derivedClassTransitivity4.js b/tests/baselines/reference/derivedClassTransitivity4.js
index 0c70f03218e..8d18e311d88 100644
--- a/tests/baselines/reference/derivedClassTransitivity4.js
+++ b/tests/baselines/reference/derivedClassTransitivity4.js
@@ -36,7 +36,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     D.prototype.foo = function () { }; // ok to drop parameters
     return D;
@@ -44,7 +45,8 @@ var D = (function (_super) {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     E.prototype.foo = function (x) { }; // ok to add optional parameters
     return E;
diff --git a/tests/baselines/reference/derivedClassWithAny.js b/tests/baselines/reference/derivedClassWithAny.js
index 34af167011d..70885570373 100644
--- a/tests/baselines/reference/derivedClassWithAny.js
+++ b/tests/baselines/reference/derivedClassWithAny.js
@@ -91,7 +91,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Object.defineProperty(D.prototype, "X", {
         get: function () {
@@ -119,7 +120,8 @@ var D = (function (_super) {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Object.defineProperty(E.prototype, "X", {
         get: function () { return ''; },
diff --git a/tests/baselines/reference/derivedClassWithPrivateInstanceShadowingProtectedInstance.js b/tests/baselines/reference/derivedClassWithPrivateInstanceShadowingProtectedInstance.js
index 2c0775efc19..24d43468dcf 100644
--- a/tests/baselines/reference/derivedClassWithPrivateInstanceShadowingProtectedInstance.js
+++ b/tests/baselines/reference/derivedClassWithPrivateInstanceShadowingProtectedInstance.js
@@ -46,7 +46,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived.prototype.fn = function () {
         return '';
diff --git a/tests/baselines/reference/derivedClassWithPrivateInstanceShadowingPublicInstance.js b/tests/baselines/reference/derivedClassWithPrivateInstanceShadowingPublicInstance.js
index 540be97d165..a6b7710ec6d 100644
--- a/tests/baselines/reference/derivedClassWithPrivateInstanceShadowingPublicInstance.js
+++ b/tests/baselines/reference/derivedClassWithPrivateInstanceShadowingPublicInstance.js
@@ -56,7 +56,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived.prototype.fn = function () {
         return '';
diff --git a/tests/baselines/reference/derivedClassWithPrivateStaticShadowingProtectedStatic.js b/tests/baselines/reference/derivedClassWithPrivateStaticShadowingProtectedStatic.js
index 93d5b49fcd0..3da7720b77e 100644
--- a/tests/baselines/reference/derivedClassWithPrivateStaticShadowingProtectedStatic.js
+++ b/tests/baselines/reference/derivedClassWithPrivateStaticShadowingProtectedStatic.js
@@ -45,7 +45,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived.fn = function () {
         return '';
diff --git a/tests/baselines/reference/derivedClassWithPrivateStaticShadowingPublicStatic.js b/tests/baselines/reference/derivedClassWithPrivateStaticShadowingPublicStatic.js
index b58acc01082..57f474affe7 100644
--- a/tests/baselines/reference/derivedClassWithPrivateStaticShadowingPublicStatic.js
+++ b/tests/baselines/reference/derivedClassWithPrivateStaticShadowingPublicStatic.js
@@ -58,7 +58,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived.fn = function () {
         return '';
diff --git a/tests/baselines/reference/derivedClassWithoutExplicitConstructor.js b/tests/baselines/reference/derivedClassWithoutExplicitConstructor.js
index 479beebbbfe..84028f1d3f2 100644
--- a/tests/baselines/reference/derivedClassWithoutExplicitConstructor.js
+++ b/tests/baselines/reference/derivedClassWithoutExplicitConstructor.js
@@ -41,7 +41,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.x = 1;
         this.y = 'hello';
     }
@@ -58,7 +59,8 @@ var Base2 = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.x = 2;
         this.y = null;
     }
diff --git a/tests/baselines/reference/derivedClassWithoutExplicitConstructor2.js b/tests/baselines/reference/derivedClassWithoutExplicitConstructor2.js
index 4dc35c5e006..6c3ce90d6f0 100644
--- a/tests/baselines/reference/derivedClassWithoutExplicitConstructor2.js
+++ b/tests/baselines/reference/derivedClassWithoutExplicitConstructor2.js
@@ -49,7 +49,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.x = 1;
         this.y = 'hello';
     }
@@ -68,7 +69,8 @@ var Base2 = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.x = 2;
         this.y = null;
     }
diff --git a/tests/baselines/reference/derivedClassWithoutExplicitConstructor3.js b/tests/baselines/reference/derivedClassWithoutExplicitConstructor3.js
index 3b0a673d378..295fbac60e1 100644
--- a/tests/baselines/reference/derivedClassWithoutExplicitConstructor3.js
+++ b/tests/baselines/reference/derivedClassWithoutExplicitConstructor3.js
@@ -63,7 +63,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived(y, z) {
-        _super.call(this, 2);
+        var _this;
+        _this = _super.call(this, 2) || this;
         this.b = '';
         this.b = y;
     }
@@ -72,7 +73,8 @@ var Derived = (function (_super) {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.x = 1;
         this.y = 'hello';
     }
@@ -90,7 +92,8 @@ var Base2 = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D(y, z) {
-        _super.call(this, 2);
+        var _this;
+        _this = _super.call(this, 2) || this;
         this.b = null;
         this.b = y;
     }
@@ -99,7 +102,8 @@ var D = (function (_super) {
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.x = 2;
         this.y = null;
     }
diff --git a/tests/baselines/reference/derivedClasses.js b/tests/baselines/reference/derivedClasses.js
index b6103940b33..27947b4f05f 100644
--- a/tests/baselines/reference/derivedClasses.js
+++ b/tests/baselines/reference/derivedClasses.js
@@ -39,7 +39,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var Red = (function (_super) {
     __extends(Red, _super);
     function Red() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Red.prototype.shade = function () {
         var _this = this;
@@ -58,7 +59,8 @@ var Color = (function () {
 var Blue = (function (_super) {
     __extends(Blue, _super);
     function Blue() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Blue.prototype.shade = function () {
         var _this = this;
diff --git a/tests/baselines/reference/derivedGenericClassWithAny.js b/tests/baselines/reference/derivedGenericClassWithAny.js
index 56daf4b7310..e31b18e11e7 100644
--- a/tests/baselines/reference/derivedGenericClassWithAny.js
+++ b/tests/baselines/reference/derivedGenericClassWithAny.js
@@ -64,7 +64,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Object.defineProperty(D.prototype, "X", {
         get: function () {
@@ -92,7 +93,8 @@ var D = (function (_super) {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Object.defineProperty(E.prototype, "X", {
         get: function () { return ''; } // error
diff --git a/tests/baselines/reference/derivedTypeAccessesHiddenBaseCallViaSuperPropertyAccess.js b/tests/baselines/reference/derivedTypeAccessesHiddenBaseCallViaSuperPropertyAccess.js
index 2e0a561e846..4430ad5a31b 100644
--- a/tests/baselines/reference/derivedTypeAccessesHiddenBaseCallViaSuperPropertyAccess.js
+++ b/tests/baselines/reference/derivedTypeAccessesHiddenBaseCallViaSuperPropertyAccess.js
@@ -34,7 +34,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived.prototype.foo = function (x) {
         return null;
diff --git a/tests/baselines/reference/derivedTypeDoesNotRequireExtendsClause.js b/tests/baselines/reference/derivedTypeDoesNotRequireExtendsClause.js
index cfbe44166c9..f6415d84965 100644
--- a/tests/baselines/reference/derivedTypeDoesNotRequireExtendsClause.js
+++ b/tests/baselines/reference/derivedTypeDoesNotRequireExtendsClause.js
@@ -39,7 +39,8 @@ var Derived = (function () {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/destructuringParameterDeclaration5.js b/tests/baselines/reference/destructuringParameterDeclaration5.js
index 2df6ce46b2c..a1f109ed49e 100644
--- a/tests/baselines/reference/destructuringParameterDeclaration5.js
+++ b/tests/baselines/reference/destructuringParameterDeclaration5.js
@@ -65,7 +65,8 @@ var Class = (function () {
 var SubClass = (function (_super) {
     __extends(SubClass, _super);
     function SubClass() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
     }
     return SubClass;
 }(Class));
@@ -77,7 +78,8 @@ var D = (function () {
 var SubD = (function (_super) {
     __extends(SubD, _super);
     function SubD() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
     }
     return SubD;
 }(D));
diff --git a/tests/baselines/reference/emitSuperCallBeforeEmitParameterPropertyDeclaration1.js b/tests/baselines/reference/emitSuperCallBeforeEmitParameterPropertyDeclaration1.js
index 88ce3f1418b..4e07d5c8655 100644
--- a/tests/baselines/reference/emitSuperCallBeforeEmitParameterPropertyDeclaration1.js
+++ b/tests/baselines/reference/emitSuperCallBeforeEmitParameterPropertyDeclaration1.js
@@ -28,9 +28,10 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B(x) {
+        var _this;
         "use strict";
         'someStringForEgngInject';
-        _super.call(this);
+        _this = _super.call(this) || this;
         this.x = x;
     }
     return B;
diff --git a/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclaration1.js b/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclaration1.js
index 920ad1f7bda..b6eabb2a418 100644
--- a/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclaration1.js
+++ b/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclaration1.js
@@ -30,9 +30,10 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
+        var _this;
         "use strict";
         'someStringForEgngInject';
-        _super.call(this);
+        _this = _super.call(this) || this;
         this.blub = 12;
     }
     return B;
diff --git a/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclarationAndParameterPropertyDeclaration1.js b/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclarationAndParameterPropertyDeclaration1.js
index 3fa18140034..0e866e98f46 100644
--- a/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclarationAndParameterPropertyDeclaration1.js
+++ b/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclarationAndParameterPropertyDeclaration1.js
@@ -28,9 +28,10 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B(x) {
+        var _this;
         "use strict";
         'someStringForEgngInject';
-        _super.call(this);
+        _this = _super.call(this) || this;
         this.x = x;
         this.blah = 2;
     }
diff --git a/tests/baselines/reference/emitThisInSuperMethodCall.js b/tests/baselines/reference/emitThisInSuperMethodCall.js
index 1350ed9d4c8..4bb83a7c172 100644
--- a/tests/baselines/reference/emitThisInSuperMethodCall.js
+++ b/tests/baselines/reference/emitThisInSuperMethodCall.js
@@ -43,7 +43,8 @@ var User = (function () {
 var RegisteredUser = (function (_super) {
     __extends(RegisteredUser, _super);
     function RegisteredUser() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     RegisteredUser.prototype.f = function () {
         (function () {
diff --git a/tests/baselines/reference/emptyModuleName.js b/tests/baselines/reference/emptyModuleName.js
index 5c85d39e1ec..2292f0a494a 100644
--- a/tests/baselines/reference/emptyModuleName.js
+++ b/tests/baselines/reference/emptyModuleName.js
@@ -14,7 +14,8 @@ var A = require("");
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/errorForwardReferenceForwadingConstructor.js b/tests/baselines/reference/errorForwardReferenceForwadingConstructor.js
index 96f6c65b85c..7b05688b8c8 100644
--- a/tests/baselines/reference/errorForwardReferenceForwadingConstructor.js
+++ b/tests/baselines/reference/errorForwardReferenceForwadingConstructor.js
@@ -30,7 +30,8 @@ var base = (function () {
 var derived = (function (_super) {
     __extends(derived, _super);
     function derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return derived;
 }(base));
diff --git a/tests/baselines/reference/errorSuperCalls.js b/tests/baselines/reference/errorSuperCalls.js
index 3e778535bb7..765fdf083b5 100644
--- a/tests/baselines/reference/errorSuperCalls.js
+++ b/tests/baselines/reference/errorSuperCalls.js
@@ -83,38 +83,38 @@ var __extends = (this && this.__extends) || function (d, b) {
 //super call in class constructor with no base type
 var NoBase = (function () {
     function NoBase() {
-        _super.call(this);
+        _this = _super.call(this) || this;
         //super call in class member initializer with no base type
-        this.p = _super.call(this);
+        this.p = _this = _super.call(this) || this;
     }
     //super call in class member function with no base type
     NoBase.prototype.fn = function () {
-        _super.call(this);
+        _this = _super.call(this) || this;
     };
     Object.defineProperty(NoBase.prototype, "foo", {
         //super call in class accessor (get and set) with no base type
         get: function () {
-            _super.call(this);
+            _this = _super.call(this) || this;
             return null;
         },
         set: function (v) {
-            _super.call(this);
+            _this = _super.call(this) || this;
         },
         enumerable: true,
         configurable: true
     });
     //super call in static class member function with no base type
     NoBase.fn = function () {
-        _super.call(this);
+        _this = _super.call(this) || this;
     };
     Object.defineProperty(NoBase, "q", {
         //super call in static class accessor (get and set) with no base type
         get: function () {
-            _super.call(this);
+            _this = _super.call(this) || this;
             return null;
         },
         set: function (n) {
-            _super.call(this);
+            _this = _super.call(this) || this;
         },
         enumerable: true,
         configurable: true
@@ -122,7 +122,7 @@ var NoBase = (function () {
     return NoBase;
 }());
 //super call in static class member initializer with no base type
-NoBase.k = _super.call(this);
+NoBase.k = _this = _super.call(this) || this;
 var Base = (function () {
     function Base() {
     }
@@ -132,8 +132,9 @@ var Derived = (function (_super) {
     __extends(Derived, _super);
     //super call with type arguments 
     function Derived() {
+        var _this;
         _super.prototype..call(this);
-        _super.call(this);
+        _this = _super.call(this) || this;
     }
     return Derived;
 }(Base));
@@ -145,22 +146,23 @@ var OtherBase = (function () {
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         //super call in class member initializer of derived type
-        this.t = _super.call(this);
+        this.t = _this = _super.call(this) || this;
     }
     OtherDerived.prototype.fn = function () {
         //super call in class member function of derived type
-        _super.call(this);
+        _this = _super.call(this) || this;
     };
     Object.defineProperty(OtherDerived.prototype, "foo", {
         //super call in class accessor (get and set) of derived type
         get: function () {
-            _super.call(this);
+            _this = _super.call(this) || this;
             return null;
         },
         set: function (n) {
-            _super.call(this);
+            _this = _super.call(this) || this;
         },
         enumerable: true,
         configurable: true
diff --git a/tests/baselines/reference/errorSuperPropertyAccess.js b/tests/baselines/reference/errorSuperPropertyAccess.js
index dbfbdb46940..18c98868e93 100644
--- a/tests/baselines/reference/errorSuperPropertyAccess.js
+++ b/tests/baselines/reference/errorSuperPropertyAccess.js
@@ -186,7 +186,8 @@ SomeBase.publicStaticMember = 0;
 var SomeDerived1 = (function (_super) {
     __extends(SomeDerived1, _super);
     function SomeDerived1() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         _super.prototype.publicMember = 1;
     }
     SomeDerived1.prototype.fn = function () {
@@ -219,7 +220,8 @@ var SomeDerived1 = (function (_super) {
 var SomeDerived2 = (function (_super) {
     __extends(SomeDerived2, _super);
     function SomeDerived2() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         _super.prototype.privateMember = 1;
     }
     SomeDerived2.prototype.fn = function () {
@@ -245,7 +247,8 @@ var SomeDerived2 = (function (_super) {
 var SomeDerived3 = (function (_super) {
     __extends(SomeDerived3, _super);
     function SomeDerived3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     SomeDerived3.fn = function () {
         _super.publicStaticMember = 3;
diff --git a/tests/baselines/reference/errorsInGenericTypeReference.js b/tests/baselines/reference/errorsInGenericTypeReference.js
index a7898810e10..d3d275ff25b 100644
--- a/tests/baselines/reference/errorsInGenericTypeReference.js
+++ b/tests/baselines/reference/errorsInGenericTypeReference.js
@@ -135,7 +135,8 @@ var testClass6 = (function () {
 var testClass7 = (function (_super) {
     __extends(testClass7, _super);
     function testClass7() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return testClass7;
 }(Foo)); // error: could not find symbol V
diff --git a/tests/baselines/reference/es6ClassSuperCodegenBug.js b/tests/baselines/reference/es6ClassSuperCodegenBug.js
index c32865478e3..88000a12bbe 100644
--- a/tests/baselines/reference/es6ClassSuperCodegenBug.js
+++ b/tests/baselines/reference/es6ClassSuperCodegenBug.js
@@ -28,11 +28,12 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
+        var _this;
         if (true) {
-            _super.call(this, 'a1', 'b1');
+            _this = _super.call(this, 'a1', 'b1') || this;
         }
         else {
-            _super.call(this, 'a2', 'b2');
+            _this = _super.call(this, 'a2', 'b2') || this;
         }
     }
     return B;
diff --git a/tests/baselines/reference/es6ClassTest.js b/tests/baselines/reference/es6ClassTest.js
index a722cce1670..0a6323630fb 100644
--- a/tests/baselines/reference/es6ClassTest.js
+++ b/tests/baselines/reference/es6ClassTest.js
@@ -102,8 +102,9 @@ var Bar = (function () {
 var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo(x, y, z) {
+        var _this;
         if (z === void 0) { z = 0; }
-        _super.call(this, x);
+        _this = _super.call(this, x) || this;
         this.y = y;
         this.z = z;
         this.gar = 0;
diff --git a/tests/baselines/reference/es6ClassTest2.js b/tests/baselines/reference/es6ClassTest2.js
index 1881e6b8c87..ebf779f7bba 100644
--- a/tests/baselines/reference/es6ClassTest2.js
+++ b/tests/baselines/reference/es6ClassTest2.js
@@ -267,7 +267,8 @@ var SuperParent = (function () {
 var SuperChild = (function (_super) {
     __extends(SuperChild, _super);
     function SuperChild() {
-        _super.call(this, 1);
+        var _this;
+        _this = _super.call(this, 1) || this;
     }
     SuperChild.prototype.b = function () {
         _super.prototype.b.call(this, 'str');
@@ -314,7 +315,8 @@ var BaseClassWithConstructor = (function () {
 var ChildClassWithoutConstructor = (function (_super) {
     __extends(ChildClassWithoutConstructor, _super);
     function ChildClassWithoutConstructor() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return ChildClassWithoutConstructor;
 }(BaseClassWithConstructor));
diff --git a/tests/baselines/reference/es6ClassTest7.js b/tests/baselines/reference/es6ClassTest7.js
index 14662410a14..6e30a1d7879 100644
--- a/tests/baselines/reference/es6ClassTest7.js
+++ b/tests/baselines/reference/es6ClassTest7.js
@@ -17,7 +17,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var Bar = (function (_super) {
     __extends(Bar, _super);
     function Bar() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Bar;
 }(M.Foo));
diff --git a/tests/baselines/reference/exportAssignmentOfGenericType1.js b/tests/baselines/reference/exportAssignmentOfGenericType1.js
index 0504bad39c7..439f74a9c9d 100644
--- a/tests/baselines/reference/exportAssignmentOfGenericType1.js
+++ b/tests/baselines/reference/exportAssignmentOfGenericType1.js
@@ -34,7 +34,8 @@ define(["require", "exports", "exportAssignmentOfGenericType1_0"], function (req
     var M = (function (_super) {
         __extends(M, _super);
         function M() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return M;
     }(q));
diff --git a/tests/baselines/reference/exportDeclarationInInternalModule.js b/tests/baselines/reference/exportDeclarationInInternalModule.js
index a9ea4bf5eda..b6eec928a07 100644
--- a/tests/baselines/reference/exportDeclarationInInternalModule.js
+++ b/tests/baselines/reference/exportDeclarationInInternalModule.js
@@ -32,7 +32,8 @@ var Bbb = (function () {
 var Aaa = (function (_super) {
     __extends(Aaa, _super);
     function Aaa() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Aaa;
 }(Bbb));
diff --git a/tests/baselines/reference/extBaseClass1.js b/tests/baselines/reference/extBaseClass1.js
index 446c6df9c94..508eea66500 100644
--- a/tests/baselines/reference/extBaseClass1.js
+++ b/tests/baselines/reference/extBaseClass1.js
@@ -37,7 +37,8 @@ var M;
     var C = (function (_super) {
         __extends(C, _super);
         function C() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return C;
     }(B));
@@ -48,7 +49,8 @@ var M;
     var C2 = (function (_super) {
         __extends(C2, _super);
         function C2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return C2;
     }(M.B));
@@ -59,7 +61,8 @@ var N;
     var C3 = (function (_super) {
         __extends(C3, _super);
         function C3() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return C3;
     }(M.B));
diff --git a/tests/baselines/reference/extBaseClass2.js b/tests/baselines/reference/extBaseClass2.js
index f7bd85d685c..14f3d69ef3e 100644
--- a/tests/baselines/reference/extBaseClass2.js
+++ b/tests/baselines/reference/extBaseClass2.js
@@ -21,7 +21,8 @@ var N;
     var C4 = (function (_super) {
         __extends(C4, _super);
         function C4() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return C4;
     }(M.B));
@@ -32,7 +33,8 @@ var M;
     var C5 = (function (_super) {
         __extends(C5, _super);
         function C5() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return C5;
     }(B));
diff --git a/tests/baselines/reference/extendAndImplementTheSameBaseType.js b/tests/baselines/reference/extendAndImplementTheSameBaseType.js
index e52e5b497ac..03bf54db78d 100644
--- a/tests/baselines/reference/extendAndImplementTheSameBaseType.js
+++ b/tests/baselines/reference/extendAndImplementTheSameBaseType.js
@@ -28,7 +28,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     D.prototype.baz = function () { };
     return D;
diff --git a/tests/baselines/reference/extendAndImplementTheSameBaseType2.js b/tests/baselines/reference/extendAndImplementTheSameBaseType2.js
index 1f4f62a42ee..50db54a05e9 100644
--- a/tests/baselines/reference/extendAndImplementTheSameBaseType2.js
+++ b/tests/baselines/reference/extendAndImplementTheSameBaseType2.js
@@ -33,7 +33,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     D.prototype.baz = function () { };
     return D;
diff --git a/tests/baselines/reference/extendBaseClassBeforeItsDeclared.js b/tests/baselines/reference/extendBaseClassBeforeItsDeclared.js
index d598389d0fa..6cab3a8c7f6 100644
--- a/tests/baselines/reference/extendBaseClassBeforeItsDeclared.js
+++ b/tests/baselines/reference/extendBaseClassBeforeItsDeclared.js
@@ -12,7 +12,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var derived = (function (_super) {
     __extends(derived, _super);
     function derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return derived;
 }(base));
diff --git a/tests/baselines/reference/extendClassExpressionFromModule.js b/tests/baselines/reference/extendClassExpressionFromModule.js
index 6532603b73c..c0cb5d49023 100644
--- a/tests/baselines/reference/extendClassExpressionFromModule.js
+++ b/tests/baselines/reference/extendClassExpressionFromModule.js
@@ -31,7 +31,8 @@ var x = foo1;
 var y = (function (_super) {
     __extends(y, _super);
     function y() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return y;
 }(x));
diff --git a/tests/baselines/reference/extendConstructSignatureInInterface.js b/tests/baselines/reference/extendConstructSignatureInInterface.js
index 20f43a948b8..6985657ced3 100644
--- a/tests/baselines/reference/extendConstructSignatureInInterface.js
+++ b/tests/baselines/reference/extendConstructSignatureInInterface.js
@@ -20,7 +20,8 @@ var CStatic;
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return E;
 }(CStatic));
diff --git a/tests/baselines/reference/extendNonClassSymbol1.js b/tests/baselines/reference/extendNonClassSymbol1.js
index 558e6d6ba57..829b1ae1a32 100644
--- a/tests/baselines/reference/extendNonClassSymbol1.js
+++ b/tests/baselines/reference/extendNonClassSymbol1.js
@@ -19,7 +19,8 @@ var x = A;
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(x)); // error, could not find symbol xs
diff --git a/tests/baselines/reference/extendNonClassSymbol2.js b/tests/baselines/reference/extendNonClassSymbol2.js
index 3785c7c5846..9a2d4fb2adf 100644
--- a/tests/baselines/reference/extendNonClassSymbol2.js
+++ b/tests/baselines/reference/extendNonClassSymbol2.js
@@ -18,7 +18,8 @@ var x = new Foo(); // legal, considered a constructor function
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(Foo)); // error, could not find symbol Foo
diff --git a/tests/baselines/reference/extendingClassFromAliasAndUsageInIndexer.js b/tests/baselines/reference/extendingClassFromAliasAndUsageInIndexer.js
index 6542492e200..db2fcdbbf36 100644
--- a/tests/baselines/reference/extendingClassFromAliasAndUsageInIndexer.js
+++ b/tests/baselines/reference/extendingClassFromAliasAndUsageInIndexer.js
@@ -51,7 +51,8 @@ var Backbone = require("./extendingClassFromAliasAndUsageInIndexer_backbone");
 var VisualizationModel = (function (_super) {
     __extends(VisualizationModel, _super);
     function VisualizationModel() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return VisualizationModel;
 }(Backbone.Model));
@@ -67,7 +68,8 @@ var Backbone = require("./extendingClassFromAliasAndUsageInIndexer_backbone");
 var VisualizationModel = (function (_super) {
     __extends(VisualizationModel, _super);
     function VisualizationModel() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return VisualizationModel;
 }(Backbone.Model));
diff --git a/tests/baselines/reference/extendsClauseAlreadySeen.js b/tests/baselines/reference/extendsClauseAlreadySeen.js
index fb9a3f12378..db11c06d782 100644
--- a/tests/baselines/reference/extendsClauseAlreadySeen.js
+++ b/tests/baselines/reference/extendsClauseAlreadySeen.js
@@ -20,7 +20,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     D.prototype.baz = function () { };
     return D;
diff --git a/tests/baselines/reference/extendsClauseAlreadySeen2.js b/tests/baselines/reference/extendsClauseAlreadySeen2.js
index 9423789dd35..f61317c2d50 100644
--- a/tests/baselines/reference/extendsClauseAlreadySeen2.js
+++ b/tests/baselines/reference/extendsClauseAlreadySeen2.js
@@ -20,7 +20,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     D.prototype.baz = function () { };
     return D;
diff --git a/tests/baselines/reference/fluentClasses.js b/tests/baselines/reference/fluentClasses.js
index 3d5efcc1b1a..68a2960b03f 100644
--- a/tests/baselines/reference/fluentClasses.js
+++ b/tests/baselines/reference/fluentClasses.js
@@ -35,7 +35,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     B.prototype.bar = function () {
         return this;
@@ -45,7 +46,8 @@ var B = (function (_super) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     C.prototype.baz = function () {
         return this;
diff --git a/tests/baselines/reference/for-inStatements.js b/tests/baselines/reference/for-inStatements.js
index 5c097a68ccc..7176a27ebc9 100644
--- a/tests/baselines/reference/for-inStatements.js
+++ b/tests/baselines/reference/for-inStatements.js
@@ -126,7 +126,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     B.prototype.boz = function () {
         for (var x in this.biz()) { }
diff --git a/tests/baselines/reference/for-inStatementsInvalid.js b/tests/baselines/reference/for-inStatementsInvalid.js
index caec9bd1987..cca8e94dcab 100644
--- a/tests/baselines/reference/for-inStatementsInvalid.js
+++ b/tests/baselines/reference/for-inStatementsInvalid.js
@@ -107,7 +107,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     B.prototype.boz = function () {
         for (var x in this.biz()) { }
diff --git a/tests/baselines/reference/forStatementsMultipleInvalidDecl.js b/tests/baselines/reference/forStatementsMultipleInvalidDecl.js
index aff01bc8565..82910ff0435 100644
--- a/tests/baselines/reference/forStatementsMultipleInvalidDecl.js
+++ b/tests/baselines/reference/forStatementsMultipleInvalidDecl.js
@@ -68,7 +68,8 @@ var C = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }(C));
diff --git a/tests/baselines/reference/functionImplementationErrors.js b/tests/baselines/reference/functionImplementationErrors.js
index 2dc6c8a1bc4..465ea54b73f 100644
--- a/tests/baselines/reference/functionImplementationErrors.js
+++ b/tests/baselines/reference/functionImplementationErrors.js
@@ -134,14 +134,16 @@ var AnotherClass = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived1;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/functionImplementations.js b/tests/baselines/reference/functionImplementations.js
index 6e37f929efe..e26e49c1b7a 100644
--- a/tests/baselines/reference/functionImplementations.js
+++ b/tests/baselines/reference/functionImplementations.js
@@ -236,7 +236,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
@@ -287,7 +288,8 @@ function f6() {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/functionSubtypingOfVarArgs.js b/tests/baselines/reference/functionSubtypingOfVarArgs.js
index 7485abe1927..c604461f32d 100644
--- a/tests/baselines/reference/functionSubtypingOfVarArgs.js
+++ b/tests/baselines/reference/functionSubtypingOfVarArgs.js
@@ -32,7 +32,8 @@ var EventBase = (function () {
 var StringEvent = (function (_super) {
     __extends(StringEvent, _super);
     function StringEvent() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     StringEvent.prototype.add = function (listener) {
         _super.prototype.add.call(this, listener);
diff --git a/tests/baselines/reference/functionSubtypingOfVarArgs2.js b/tests/baselines/reference/functionSubtypingOfVarArgs2.js
index 33d0e8c7e03..38a98a3f114 100644
--- a/tests/baselines/reference/functionSubtypingOfVarArgs2.js
+++ b/tests/baselines/reference/functionSubtypingOfVarArgs2.js
@@ -32,7 +32,8 @@ var EventBase = (function () {
 var StringEvent = (function (_super) {
     __extends(StringEvent, _super);
     function StringEvent() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     StringEvent.prototype.add = function (listener) {
         _super.prototype.add.call(this, listener);
diff --git a/tests/baselines/reference/generatedContextualTyping.js b/tests/baselines/reference/generatedContextualTyping.js
index e5488121d34..5c512883a10 100644
--- a/tests/baselines/reference/generatedContextualTyping.js
+++ b/tests/baselines/reference/generatedContextualTyping.js
@@ -369,14 +369,16 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived1;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/genericBaseClassLiteralProperty.js b/tests/baselines/reference/genericBaseClassLiteralProperty.js
index 5aa43d78826..25dfb7ae722 100644
--- a/tests/baselines/reference/genericBaseClassLiteralProperty.js
+++ b/tests/baselines/reference/genericBaseClassLiteralProperty.js
@@ -26,7 +26,8 @@ var BaseClass = (function () {
 var SubClass = (function (_super) {
     __extends(SubClass, _super);
     function SubClass() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     SubClass.prototype.Error = function () {
         var x = this._getValue1();
diff --git a/tests/baselines/reference/genericBaseClassLiteralProperty2.js b/tests/baselines/reference/genericBaseClassLiteralProperty2.js
index 3226f1cd659..e39353b6a7f 100644
--- a/tests/baselines/reference/genericBaseClassLiteralProperty2.js
+++ b/tests/baselines/reference/genericBaseClassLiteralProperty2.js
@@ -35,7 +35,8 @@ var BaseCollection2 = (function () {
 var DataView2 = (function (_super) {
     __extends(DataView2, _super);
     function DataView2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     DataView2.prototype.fillItems = function (item) {
         this._itemsByKey['dummy'] = item;
diff --git a/tests/baselines/reference/genericCallWithConstraintsTypeArgumentInference.js b/tests/baselines/reference/genericCallWithConstraintsTypeArgumentInference.js
index 04d5bd2d997..53c02a85113 100644
--- a/tests/baselines/reference/genericCallWithConstraintsTypeArgumentInference.js
+++ b/tests/baselines/reference/genericCallWithConstraintsTypeArgumentInference.js
@@ -122,14 +122,16 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived));
diff --git a/tests/baselines/reference/genericCallWithObjectTypeArgs2.js b/tests/baselines/reference/genericCallWithObjectTypeArgs2.js
index 509dd9a1136..3835a4dd787 100644
--- a/tests/baselines/reference/genericCallWithObjectTypeArgs2.js
+++ b/tests/baselines/reference/genericCallWithObjectTypeArgs2.js
@@ -46,14 +46,16 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/genericCallWithObjectTypeArgsAndConstraints2.js b/tests/baselines/reference/genericCallWithObjectTypeArgsAndConstraints2.js
index d3f18e0bfcb..a16f8bcac68 100644
--- a/tests/baselines/reference/genericCallWithObjectTypeArgsAndConstraints2.js
+++ b/tests/baselines/reference/genericCallWithObjectTypeArgsAndConstraints2.js
@@ -54,7 +54,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/genericCallWithObjectTypeArgsAndConstraints3.js b/tests/baselines/reference/genericCallWithObjectTypeArgsAndConstraints3.js
index acab51690d3..410675804af 100644
--- a/tests/baselines/reference/genericCallWithObjectTypeArgsAndConstraints3.js
+++ b/tests/baselines/reference/genericCallWithObjectTypeArgsAndConstraints3.js
@@ -52,14 +52,16 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/genericCallbacksAndClassHierarchy.js b/tests/baselines/reference/genericCallbacksAndClassHierarchy.js
index 31b4cd181b9..3fbb7c8a901 100644
--- a/tests/baselines/reference/genericCallbacksAndClassHierarchy.js
+++ b/tests/baselines/reference/genericCallbacksAndClassHierarchy.js
@@ -46,7 +46,8 @@ var M;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(C1));
diff --git a/tests/baselines/reference/genericClassExpressionInFunction.js b/tests/baselines/reference/genericClassExpressionInFunction.js
index f334da52625..d14b70b6312 100644
--- a/tests/baselines/reference/genericClassExpressionInFunction.js
+++ b/tests/baselines/reference/genericClassExpressionInFunction.js
@@ -47,7 +47,8 @@ function B1() {
     return (function (_super) {
         __extends(class_1, _super);
         function class_1() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return class_1;
     }(A));
@@ -57,7 +58,8 @@ var B2 = (function () {
         this.anon = (function (_super) {
             __extends(class_2, _super);
             function class_2() {
-                _super.apply(this, arguments);
+                var _this = _super.apply(this, arguments) || this;
+                return _this;
             }
             return class_2;
         }(A));
@@ -68,7 +70,8 @@ function B3() {
     return (function (_super) {
         __extends(Inner, _super);
         function Inner() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Inner;
     }(A));
@@ -77,14 +80,16 @@ function B3() {
 var K = (function (_super) {
     __extends(K, _super);
     function K() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return K;
 }(B1()));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }((new B2().anon)));
@@ -92,7 +97,8 @@ var b3Number = B3();
 var S = (function (_super) {
     __extends(S, _super);
     function S() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return S;
 }(b3Number));
diff --git a/tests/baselines/reference/genericClassInheritsConstructorFromNonGenericClass.js b/tests/baselines/reference/genericClassInheritsConstructorFromNonGenericClass.js
index 9f71ace88a9..a6c14b9ba0f 100644
--- a/tests/baselines/reference/genericClassInheritsConstructorFromNonGenericClass.js
+++ b/tests/baselines/reference/genericClassInheritsConstructorFromNonGenericClass.js
@@ -14,14 +14,16 @@ var __extends = (this && this.__extends) || function (d, b) {
 var A = (function (_super) {
     __extends(A, _super);
     function A() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return A;
 }(B));
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(C));
diff --git a/tests/baselines/reference/genericClassPropertyInheritanceSpecialization.js b/tests/baselines/reference/genericClassPropertyInheritanceSpecialization.js
index 8f90c2fb6e4..0cc1f5867a2 100644
--- a/tests/baselines/reference/genericClassPropertyInheritanceSpecialization.js
+++ b/tests/baselines/reference/genericClassPropertyInheritanceSpecialization.js
@@ -109,7 +109,8 @@ var PortalFx;
                 var Validator = (function (_super) {
                     __extends(Validator, _super);
                     function Validator(message) {
-                        _super.call(this, message);
+                        var _this;
+                        _this = _super.call(this, message) || this;
                     }
                     return Validator;
                 }(Portal.Controls.Validators.Validator));
diff --git a/tests/baselines/reference/genericClassStaticMethod.js b/tests/baselines/reference/genericClassStaticMethod.js
index 394e6650e0a..2124f414172 100644
--- a/tests/baselines/reference/genericClassStaticMethod.js
+++ b/tests/baselines/reference/genericClassStaticMethod.js
@@ -26,7 +26,8 @@ var Foo = (function () {
 var Bar = (function (_super) {
     __extends(Bar, _super);
     function Bar() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Bar.getFoo = function () {
     };
diff --git a/tests/baselines/reference/genericClasses3.js b/tests/baselines/reference/genericClasses3.js
index 2bd33efb3dc..6f10b979c4a 100644
--- a/tests/baselines/reference/genericClasses3.js
+++ b/tests/baselines/reference/genericClasses3.js
@@ -31,7 +31,8 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(B));
diff --git a/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes.js b/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes.js
index d2bf12667fc..4581ecc31ec 100644
--- a/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes.js
+++ b/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes.js
@@ -52,7 +52,8 @@ var EndGate;
         var NumberTween = (function (_super) {
             __extends(NumberTween, _super);
             function NumberTween(from) {
-                _super.call(this, from);
+                var _this;
+                _this = _super.call(this, from) || this;
             }
             return NumberTween;
         }(Tweening.Tween));
diff --git a/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes2.js b/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes2.js
index f61f57cb615..8f1e9c8365f 100644
--- a/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes2.js
+++ b/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes2.js
@@ -51,7 +51,8 @@ var EndGate;
         var NumberTween = (function (_super) {
             __extends(NumberTween, _super);
             function NumberTween(from) {
-                _super.call(this, from);
+                var _this;
+                _this = _super.call(this, from) || this;
             }
             return NumberTween;
         }(Tweening.Tween));
diff --git a/tests/baselines/reference/genericDerivedTypeWithSpecializedBase.js b/tests/baselines/reference/genericDerivedTypeWithSpecializedBase.js
index 906145850f1..454bc77ae5b 100644
--- a/tests/baselines/reference/genericDerivedTypeWithSpecializedBase.js
+++ b/tests/baselines/reference/genericDerivedTypeWithSpecializedBase.js
@@ -26,7 +26,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/genericDerivedTypeWithSpecializedBase2.js b/tests/baselines/reference/genericDerivedTypeWithSpecializedBase2.js
index 1c73075acc4..26749718d43 100644
--- a/tests/baselines/reference/genericDerivedTypeWithSpecializedBase2.js
+++ b/tests/baselines/reference/genericDerivedTypeWithSpecializedBase2.js
@@ -26,7 +26,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/genericInheritedDefaultConstructors.js b/tests/baselines/reference/genericInheritedDefaultConstructors.js
index 170ef89abb2..e7c32cbe73f 100644
--- a/tests/baselines/reference/genericInheritedDefaultConstructors.js
+++ b/tests/baselines/reference/genericInheritedDefaultConstructors.js
@@ -24,7 +24,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/genericPrototypeProperty2.js b/tests/baselines/reference/genericPrototypeProperty2.js
index 3f1b6e21adc..ccaf6fa8807 100644
--- a/tests/baselines/reference/genericPrototypeProperty2.js
+++ b/tests/baselines/reference/genericPrototypeProperty2.js
@@ -29,7 +29,8 @@ var BaseEvent = (function () {
 var MyEvent = (function (_super) {
     __extends(MyEvent, _super);
     function MyEvent() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return MyEvent;
 }(BaseEvent));
@@ -41,7 +42,8 @@ var BaseEventWrapper = (function () {
 var MyEventWrapper = (function (_super) {
     __extends(MyEventWrapper, _super);
     function MyEventWrapper() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return MyEventWrapper;
 }(BaseEventWrapper));
diff --git a/tests/baselines/reference/genericPrototypeProperty3.js b/tests/baselines/reference/genericPrototypeProperty3.js
index b7cca85561c..85658593705 100644
--- a/tests/baselines/reference/genericPrototypeProperty3.js
+++ b/tests/baselines/reference/genericPrototypeProperty3.js
@@ -28,7 +28,8 @@ var BaseEvent = (function () {
 var MyEvent = (function (_super) {
     __extends(MyEvent, _super);
     function MyEvent() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return MyEvent;
 }(BaseEvent));
@@ -40,7 +41,8 @@ var BaseEventWrapper = (function () {
 var MyEventWrapper = (function (_super) {
     __extends(MyEventWrapper, _super);
     function MyEventWrapper() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return MyEventWrapper;
 }(BaseEventWrapper));
diff --git a/tests/baselines/reference/genericRecursiveImplicitConstructorErrors2.js b/tests/baselines/reference/genericRecursiveImplicitConstructorErrors2.js
index 73012f714e8..e567e2a8042 100644
--- a/tests/baselines/reference/genericRecursiveImplicitConstructorErrors2.js
+++ b/tests/baselines/reference/genericRecursiveImplicitConstructorErrors2.js
@@ -57,7 +57,8 @@ var TypeScript2;
     var PullTypeSymbol = (function (_super) {
         __extends(PullTypeSymbol, _super);
         function PullTypeSymbol() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return PullTypeSymbol;
     }(PullSymbol));
diff --git a/tests/baselines/reference/genericRecursiveImplicitConstructorErrors3.js b/tests/baselines/reference/genericRecursiveImplicitConstructorErrors3.js
index 61cb758c48e..226fede58b6 100644
--- a/tests/baselines/reference/genericRecursiveImplicitConstructorErrors3.js
+++ b/tests/baselines/reference/genericRecursiveImplicitConstructorErrors3.js
@@ -59,7 +59,8 @@ var TypeScript;
     var PullTypeSymbol = (function (_super) {
         __extends(PullTypeSymbol, _super);
         function PullTypeSymbol() {
-            _super.apply(this, arguments);
+            var _this;
+            _this = _super.apply(this, arguments) || this;
             this._elementType = null;
         }
         PullTypeSymbol.prototype.toString = function (scopeSymbol, useConstraintInName) {
diff --git a/tests/baselines/reference/genericTypeAssertions2.js b/tests/baselines/reference/genericTypeAssertions2.js
index 02a51aed35d..31d2b3976db 100644
--- a/tests/baselines/reference/genericTypeAssertions2.js
+++ b/tests/baselines/reference/genericTypeAssertions2.js
@@ -28,7 +28,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     B.prototype.bar = function () {
         return null;
diff --git a/tests/baselines/reference/genericTypeAssertions4.js b/tests/baselines/reference/genericTypeAssertions4.js
index 2c5bbf51d7f..41a187edb6a 100644
--- a/tests/baselines/reference/genericTypeAssertions4.js
+++ b/tests/baselines/reference/genericTypeAssertions4.js
@@ -40,7 +40,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     B.prototype.bar = function () { return 1; };
     return B;
@@ -48,7 +49,8 @@ var B = (function (_super) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     C.prototype.baz = function () { return 1; };
     return C;
diff --git a/tests/baselines/reference/genericTypeAssertions6.js b/tests/baselines/reference/genericTypeAssertions6.js
index 5bc7a943163..b776668f2e2 100644
--- a/tests/baselines/reference/genericTypeAssertions6.js
+++ b/tests/baselines/reference/genericTypeAssertions6.js
@@ -44,7 +44,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     B.prototype.g = function (x) {
         var a = x;
diff --git a/tests/baselines/reference/genericTypeConstraints.js b/tests/baselines/reference/genericTypeConstraints.js
index 5f4bb41a83f..761220ae11a 100644
--- a/tests/baselines/reference/genericTypeConstraints.js
+++ b/tests/baselines/reference/genericTypeConstraints.js
@@ -38,7 +38,8 @@ var Bar = (function () {
 var BarExtended = (function (_super) {
     __extends(BarExtended, _super);
     function BarExtended() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
     }
     return BarExtended;
 }(Bar));
diff --git a/tests/baselines/reference/genericTypeReferenceWithoutTypeArgument.js b/tests/baselines/reference/genericTypeReferenceWithoutTypeArgument.js
index 7fe6c49d65e..39468204a5a 100644
--- a/tests/baselines/reference/genericTypeReferenceWithoutTypeArgument.js
+++ b/tests/baselines/reference/genericTypeReferenceWithoutTypeArgument.js
@@ -60,7 +60,8 @@ var g = function f(x) { var y; return y; };
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(C));
@@ -76,7 +77,8 @@ var M;
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D2;
 }(M.E));
diff --git a/tests/baselines/reference/genericTypeReferenceWithoutTypeArgument2.js b/tests/baselines/reference/genericTypeReferenceWithoutTypeArgument2.js
index 12be456a8a8..a41d459b445 100644
--- a/tests/baselines/reference/genericTypeReferenceWithoutTypeArgument2.js
+++ b/tests/baselines/reference/genericTypeReferenceWithoutTypeArgument2.js
@@ -55,14 +55,16 @@ var g = function f(x) { var y; return y; };
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(I));
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D2;
 }(M.C));
diff --git a/tests/baselines/reference/genericWithIndexerOfTypeParameterType2.js b/tests/baselines/reference/genericWithIndexerOfTypeParameterType2.js
index 1f016b401ed..c0498b351e1 100644
--- a/tests/baselines/reference/genericWithIndexerOfTypeParameterType2.js
+++ b/tests/baselines/reference/genericWithIndexerOfTypeParameterType2.js
@@ -31,7 +31,8 @@ define(["require", "exports"], function (require, exports) {
     var List = (function (_super) {
         __extends(List, _super);
         function List() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         List.prototype.Bar = function () { };
         return List;
@@ -46,7 +47,8 @@ define(["require", "exports"], function (require, exports) {
     var ListItem = (function (_super) {
         __extends(ListItem, _super);
         function ListItem() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return ListItem;
     }(CollectionItem));
diff --git a/tests/baselines/reference/heterogeneousArrayLiterals.js b/tests/baselines/reference/heterogeneousArrayLiterals.js
index e482f0d33d3..e3c50cfa8f7 100644
--- a/tests/baselines/reference/heterogeneousArrayLiterals.js
+++ b/tests/baselines/reference/heterogeneousArrayLiterals.js
@@ -160,14 +160,16 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/ifDoWhileStatements.js b/tests/baselines/reference/ifDoWhileStatements.js
index 75762ffbb54..af1e3be18ff 100644
--- a/tests/baselines/reference/ifDoWhileStatements.js
+++ b/tests/baselines/reference/ifDoWhileStatements.js
@@ -177,7 +177,8 @@ var C = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }(C));
diff --git a/tests/baselines/reference/illegalSuperCallsInConstructor.js b/tests/baselines/reference/illegalSuperCallsInConstructor.js
index 88671ce1cee..e27a9789cb1 100644
--- a/tests/baselines/reference/illegalSuperCallsInConstructor.js
+++ b/tests/baselines/reference/illegalSuperCallsInConstructor.js
@@ -34,16 +34,17 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var r2 = function () { return _super.call(this); };
-        var r3 = function () { _super.call(this); };
-        var r4 = function () { _super.call(this); };
+        var _this;
+        var r2 = function () { return _this = _super.call(_this) || _this; };
+        var r3 = function () { _this = _super.call(_this) || _this; };
+        var r4 = function () { _this = _super.call(this) || this; };
         var r5 = {
             get foo() {
-                _super.call(this);
+                _this = _super.call(this) || this;
                 return 1;
             },
             set foo(v) {
-                _super.call(this);
+                _this = _super.call(this) || this;
             }
         };
     }
diff --git a/tests/baselines/reference/implementClausePrecedingExtends.js b/tests/baselines/reference/implementClausePrecedingExtends.js
index ba3583c3051..0dfc867a2f7 100644
--- a/tests/baselines/reference/implementClausePrecedingExtends.js
+++ b/tests/baselines/reference/implementClausePrecedingExtends.js
@@ -16,7 +16,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/implementingAnInterfaceExtendingClassWithPrivates2.js b/tests/baselines/reference/implementingAnInterfaceExtendingClassWithPrivates2.js
index 8fec5dc27da..033d6150194 100644
--- a/tests/baselines/reference/implementingAnInterfaceExtendingClassWithPrivates2.js
+++ b/tests/baselines/reference/implementingAnInterfaceExtendingClassWithPrivates2.js
@@ -99,21 +99,24 @@ var Foo = (function () {
 var Bar = (function (_super) {
     __extends(Bar, _super);
     function Bar() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Bar;
 }(Foo));
 var Bar2 = (function (_super) {
     __extends(Bar2, _super);
     function Bar2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Bar2;
 }(Foo));
 var Bar3 = (function (_super) {
     __extends(Bar3, _super);
     function Bar3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Bar3;
 }(Foo));
@@ -128,28 +131,32 @@ var M;
     var Baz = (function (_super) {
         __extends(Baz, _super);
         function Baz() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Baz;
     }(Foo));
     var Bar = (function (_super) {
         __extends(Bar, _super);
         function Bar() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Bar;
     }(Foo));
     var Bar2 = (function (_super) {
         __extends(Bar2, _super);
         function Bar2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Bar2;
     }(Foo));
     var Bar3 = (function (_super) {
         __extends(Bar3, _super);
         function Bar3() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Bar3;
     }(Foo));
@@ -165,14 +172,16 @@ var M2;
     var Baz = (function (_super) {
         __extends(Baz, _super);
         function Baz() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Baz;
     }(Foo));
     var Bar = (function (_super) {
         __extends(Bar, _super);
         function Bar() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Bar;
     }(Foo));
@@ -183,14 +192,16 @@ var M2;
     var Bar2 = (function (_super) {
         __extends(Bar2, _super);
         function Bar2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Bar2;
     }(Foo));
     var Bar3 = (function (_super) {
         __extends(Bar3, _super);
         function Bar3() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Bar3;
     }(Foo));
diff --git a/tests/baselines/reference/implementingAnInterfaceExtendingClassWithProtecteds.js b/tests/baselines/reference/implementingAnInterfaceExtendingClassWithProtecteds.js
index 915e652056c..78cfb6b51b9 100644
--- a/tests/baselines/reference/implementingAnInterfaceExtendingClassWithProtecteds.js
+++ b/tests/baselines/reference/implementingAnInterfaceExtendingClassWithProtecteds.js
@@ -75,28 +75,32 @@ var Bar4 = (function () {
 var Bar5 = (function (_super) {
     __extends(Bar5, _super);
     function Bar5() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Bar5;
 }(Foo));
 var Bar6 = (function (_super) {
     __extends(Bar6, _super);
     function Bar6() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Bar6;
 }(Foo));
 var Bar7 = (function (_super) {
     __extends(Bar7, _super);
     function Bar7() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Bar7;
 }(Foo));
 var Bar8 = (function (_super) {
     __extends(Bar8, _super);
     function Bar8() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Bar8;
 }(Foo));
diff --git a/tests/baselines/reference/importAsBaseClass.js b/tests/baselines/reference/importAsBaseClass.js
index 60e142dd5f7..d9f40f83051 100644
--- a/tests/baselines/reference/importAsBaseClass.js
+++ b/tests/baselines/reference/importAsBaseClass.js
@@ -30,7 +30,8 @@ var Greeter = require("./importAsBaseClass_0");
 var Hello = (function (_super) {
     __extends(Hello, _super);
     function Hello() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Hello;
 }(Greeter));
diff --git a/tests/baselines/reference/importHelpers.js b/tests/baselines/reference/importHelpers.js
index f850b5cf177..6641ef9d212 100644
--- a/tests/baselines/reference/importHelpers.js
+++ b/tests/baselines/reference/importHelpers.js
@@ -45,7 +45,8 @@ exports.A = A;
 var B = (function (_super) {
     tslib_1.__extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
@@ -93,7 +94,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/importHelpersAmd.js b/tests/baselines/reference/importHelpersAmd.js
index bb02cbf0417..89fab70bdba 100644
--- a/tests/baselines/reference/importHelpersAmd.js
+++ b/tests/baselines/reference/importHelpersAmd.js
@@ -32,7 +32,8 @@ define(["require", "exports", "tslib", "./a"], function (require, exports, tslib
     var B = (function (_super) {
         tslib_1.__extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(a_1.A));
diff --git a/tests/baselines/reference/importHelpersInIsolatedModules.js b/tests/baselines/reference/importHelpersInIsolatedModules.js
index a5929bc152c..2a97d3d2d87 100644
--- a/tests/baselines/reference/importHelpersInIsolatedModules.js
+++ b/tests/baselines/reference/importHelpersInIsolatedModules.js
@@ -45,7 +45,8 @@ exports.A = A;
 var B = (function (_super) {
     tslib_1.__extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
@@ -78,7 +79,8 @@ var A = (function () {
 var B = (function (_super) {
     tslib_1.__extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/importHelpersNoHelpers.js b/tests/baselines/reference/importHelpersNoHelpers.js
index 8c5afc99ece..d5f8db60f97 100644
--- a/tests/baselines/reference/importHelpersNoHelpers.js
+++ b/tests/baselines/reference/importHelpersNoHelpers.js
@@ -39,7 +39,8 @@ exports.A = A;
 var B = (function (_super) {
     tslib_1.__extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
@@ -87,7 +88,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/importHelpersNoModule.js b/tests/baselines/reference/importHelpersNoModule.js
index 36bc0c5f76b..5891922f9f2 100644
--- a/tests/baselines/reference/importHelpersNoModule.js
+++ b/tests/baselines/reference/importHelpersNoModule.js
@@ -37,7 +37,8 @@ exports.A = A;
 var B = (function (_super) {
     tslib_1.__extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
@@ -85,7 +86,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/importHelpersOutFile.js b/tests/baselines/reference/importHelpersOutFile.js
index cb50330c20c..b4c2040aa71 100644
--- a/tests/baselines/reference/importHelpersOutFile.js
+++ b/tests/baselines/reference/importHelpersOutFile.js
@@ -35,7 +35,8 @@ define("b", ["require", "exports", "tslib", "a"], function (require, exports, ts
     var B = (function (_super) {
         tslib_1.__extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(a_1.A));
@@ -46,7 +47,8 @@ define("c", ["require", "exports", "tslib", "a"], function (require, exports, ts
     var C = (function (_super) {
         tslib_2.__extends(C, _super);
         function C() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return C;
     }(a_2.A));
diff --git a/tests/baselines/reference/importHelpersSystem.js b/tests/baselines/reference/importHelpersSystem.js
index 3c1ee19ec48..552bd0ed404 100644
--- a/tests/baselines/reference/importHelpersSystem.js
+++ b/tests/baselines/reference/importHelpersSystem.js
@@ -51,7 +51,8 @@ System.register(["tslib", "./a"], function (exports_1, context_1) {
             B = (function (_super) {
                 tslib_1.__extends(B, _super);
                 function B() {
-                    _super.apply(this, arguments);
+                    var _this = _super.apply(this, arguments) || this;
+                    return _this;
                 }
                 return B;
             }(a_1.A));
diff --git a/tests/baselines/reference/importShadowsGlobalName.js b/tests/baselines/reference/importShadowsGlobalName.js
index 316a94d9069..b4950b039f3 100644
--- a/tests/baselines/reference/importShadowsGlobalName.js
+++ b/tests/baselines/reference/importShadowsGlobalName.js
@@ -31,7 +31,8 @@ define(["require", "exports", "Foo"], function (require, exports, Error) {
     var Bar = (function (_super) {
         __extends(Bar, _super);
         function Bar() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Bar;
     }(Error));
diff --git a/tests/baselines/reference/importUsedInExtendsList1.js b/tests/baselines/reference/importUsedInExtendsList1.js
index b9827d5bc93..956e20a1045 100644
--- a/tests/baselines/reference/importUsedInExtendsList1.js
+++ b/tests/baselines/reference/importUsedInExtendsList1.js
@@ -31,7 +31,8 @@ var foo = require("./importUsedInExtendsList1_require");
 var Sub = (function (_super) {
     __extends(Sub, _super);
     function Sub() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Sub;
 }(foo.Super));
diff --git a/tests/baselines/reference/indexerConstraints2.js b/tests/baselines/reference/indexerConstraints2.js
index dd143da97e6..c8b910abb2d 100644
--- a/tests/baselines/reference/indexerConstraints2.js
+++ b/tests/baselines/reference/indexerConstraints2.js
@@ -42,7 +42,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
@@ -55,7 +56,8 @@ var F = (function () {
 var G = (function (_super) {
     __extends(G, _super);
     function G() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return G;
 }(F));
@@ -68,7 +70,8 @@ var H = (function () {
 var I = (function (_super) {
     __extends(I, _super);
     function I() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return I;
 }(H));
@@ -81,7 +84,8 @@ var J = (function () {
 var K = (function (_super) {
     __extends(K, _super);
     function K() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return K;
 }(J));
diff --git a/tests/baselines/reference/indirectSelfReference.js b/tests/baselines/reference/indirectSelfReference.js
index 66d23a45b72..c1c77ec5fc9 100644
--- a/tests/baselines/reference/indirectSelfReference.js
+++ b/tests/baselines/reference/indirectSelfReference.js
@@ -11,14 +11,16 @@ var __extends = (this && this.__extends) || function (d, b) {
 var a = (function (_super) {
     __extends(a, _super);
     function a() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return a;
 }(b));
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return b;
 }(a));
diff --git a/tests/baselines/reference/indirectSelfReferenceGeneric.js b/tests/baselines/reference/indirectSelfReferenceGeneric.js
index 99ab918e631..366ad1f0af5 100644
--- a/tests/baselines/reference/indirectSelfReferenceGeneric.js
+++ b/tests/baselines/reference/indirectSelfReferenceGeneric.js
@@ -11,14 +11,16 @@ var __extends = (this && this.__extends) || function (d, b) {
 var a = (function (_super) {
     __extends(a, _super);
     function a() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return a;
 }(b));
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return b;
 }(a));
diff --git a/tests/baselines/reference/infinitelyExpandingTypesNonGenericBase.js b/tests/baselines/reference/infinitelyExpandingTypesNonGenericBase.js
index 6321f77d31f..9b145b55d04 100644
--- a/tests/baselines/reference/infinitelyExpandingTypesNonGenericBase.js
+++ b/tests/baselines/reference/infinitelyExpandingTypesNonGenericBase.js
@@ -43,7 +43,8 @@ var Base = (function () {
 var A = (function (_super) {
     __extends(A, _super);
     function A() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return A;
 }(Base));
diff --git a/tests/baselines/reference/inheritFromGenericTypeParameter.js b/tests/baselines/reference/inheritFromGenericTypeParameter.js
index f5bc099cb8d..5db269f7c58 100644
--- a/tests/baselines/reference/inheritFromGenericTypeParameter.js
+++ b/tests/baselines/reference/inheritFromGenericTypeParameter.js
@@ -11,7 +11,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(T));
diff --git a/tests/baselines/reference/inheritSameNamePrivatePropertiesFromSameOrigin.js b/tests/baselines/reference/inheritSameNamePrivatePropertiesFromSameOrigin.js
index 9462df7a3c3..7f3e872245b 100644
--- a/tests/baselines/reference/inheritSameNamePrivatePropertiesFromSameOrigin.js
+++ b/tests/baselines/reference/inheritSameNamePrivatePropertiesFromSameOrigin.js
@@ -24,14 +24,16 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(B));
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }(B));
diff --git a/tests/baselines/reference/inheritance.js b/tests/baselines/reference/inheritance.js
index 52fbfaffdde..c4acea22260 100644
--- a/tests/baselines/reference/inheritance.js
+++ b/tests/baselines/reference/inheritance.js
@@ -53,14 +53,16 @@ var B2 = (function () {
 var D1 = (function (_super) {
     __extends(D1, _super);
     function D1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D1;
 }(B1));
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D2;
 }(B2));
@@ -72,7 +74,8 @@ var N = (function () {
 var ND = (function (_super) {
     __extends(ND, _super);
     function ND() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return ND;
 }(N));
@@ -86,7 +89,8 @@ var Good = (function () {
 var Baad = (function (_super) {
     __extends(Baad, _super);
     function Baad() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Baad.prototype.f = function () { return 0; };
     Baad.prototype.g = function (n) { return 0; };
diff --git a/tests/baselines/reference/inheritance1.js b/tests/baselines/reference/inheritance1.js
index c65155ee55c..f555d5bf694 100644
--- a/tests/baselines/reference/inheritance1.js
+++ b/tests/baselines/reference/inheritance1.js
@@ -75,7 +75,8 @@ var Control = (function () {
 var Button = (function (_super) {
     __extends(Button, _super);
     function Button() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Button.prototype.select = function () { };
     return Button;
@@ -83,7 +84,8 @@ var Button = (function (_super) {
 var TextBox = (function (_super) {
     __extends(TextBox, _super);
     function TextBox() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     TextBox.prototype.select = function () { };
     return TextBox;
@@ -91,14 +93,16 @@ var TextBox = (function (_super) {
 var ImageBase = (function (_super) {
     __extends(ImageBase, _super);
     function ImageBase() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return ImageBase;
 }(Control));
 var Image1 = (function (_super) {
     __extends(Image1, _super);
     function Image1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Image1;
 }(Control));
diff --git a/tests/baselines/reference/inheritanceGrandParentPrivateMemberCollision.js b/tests/baselines/reference/inheritanceGrandParentPrivateMemberCollision.js
index b416cf3fb93..2ed366d7b8a 100644
--- a/tests/baselines/reference/inheritanceGrandParentPrivateMemberCollision.js
+++ b/tests/baselines/reference/inheritanceGrandParentPrivateMemberCollision.js
@@ -25,14 +25,16 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     C.prototype.myMethod = function () { };
     return C;
diff --git a/tests/baselines/reference/inheritanceGrandParentPrivateMemberCollisionWithPublicMember.js b/tests/baselines/reference/inheritanceGrandParentPrivateMemberCollisionWithPublicMember.js
index 25a977531ca..369c6b20a14 100644
--- a/tests/baselines/reference/inheritanceGrandParentPrivateMemberCollisionWithPublicMember.js
+++ b/tests/baselines/reference/inheritanceGrandParentPrivateMemberCollisionWithPublicMember.js
@@ -25,14 +25,16 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     C.prototype.myMethod = function () { };
     return C;
diff --git a/tests/baselines/reference/inheritanceGrandParentPublicMemberCollisionWithPrivateMember.js b/tests/baselines/reference/inheritanceGrandParentPublicMemberCollisionWithPrivateMember.js
index dfd05556925..d884364d95c 100644
--- a/tests/baselines/reference/inheritanceGrandParentPublicMemberCollisionWithPrivateMember.js
+++ b/tests/baselines/reference/inheritanceGrandParentPublicMemberCollisionWithPrivateMember.js
@@ -25,14 +25,16 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     C.prototype.myMethod = function () { };
     return C;
diff --git a/tests/baselines/reference/inheritanceMemberAccessorOverridingAccessor.js b/tests/baselines/reference/inheritanceMemberAccessorOverridingAccessor.js
index b4efaa89621..c1289f99a78 100644
--- a/tests/baselines/reference/inheritanceMemberAccessorOverridingAccessor.js
+++ b/tests/baselines/reference/inheritanceMemberAccessorOverridingAccessor.js
@@ -40,7 +40,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Object.defineProperty(b.prototype, "x", {
         get: function () {
diff --git a/tests/baselines/reference/inheritanceMemberAccessorOverridingMethod.js b/tests/baselines/reference/inheritanceMemberAccessorOverridingMethod.js
index 5044a8e03ac..665b547154d 100644
--- a/tests/baselines/reference/inheritanceMemberAccessorOverridingMethod.js
+++ b/tests/baselines/reference/inheritanceMemberAccessorOverridingMethod.js
@@ -31,7 +31,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Object.defineProperty(b.prototype, "x", {
         get: function () {
diff --git a/tests/baselines/reference/inheritanceMemberAccessorOverridingProperty.js b/tests/baselines/reference/inheritanceMemberAccessorOverridingProperty.js
index 6ebdc336a64..a9a92003542 100644
--- a/tests/baselines/reference/inheritanceMemberAccessorOverridingProperty.js
+++ b/tests/baselines/reference/inheritanceMemberAccessorOverridingProperty.js
@@ -26,7 +26,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Object.defineProperty(b.prototype, "x", {
         get: function () {
diff --git a/tests/baselines/reference/inheritanceMemberFuncOverridingAccessor.js b/tests/baselines/reference/inheritanceMemberFuncOverridingAccessor.js
index 3ddff027c1a..17541ee163d 100644
--- a/tests/baselines/reference/inheritanceMemberFuncOverridingAccessor.js
+++ b/tests/baselines/reference/inheritanceMemberFuncOverridingAccessor.js
@@ -37,7 +37,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     b.prototype.x = function () {
         return "20";
diff --git a/tests/baselines/reference/inheritanceMemberFuncOverridingMethod.js b/tests/baselines/reference/inheritanceMemberFuncOverridingMethod.js
index a6c3beea4ef..a154d0426a9 100644
--- a/tests/baselines/reference/inheritanceMemberFuncOverridingMethod.js
+++ b/tests/baselines/reference/inheritanceMemberFuncOverridingMethod.js
@@ -28,7 +28,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     b.prototype.x = function () {
         return "20";
diff --git a/tests/baselines/reference/inheritanceMemberFuncOverridingProperty.js b/tests/baselines/reference/inheritanceMemberFuncOverridingProperty.js
index 94b602d29d9..be10895642e 100644
--- a/tests/baselines/reference/inheritanceMemberFuncOverridingProperty.js
+++ b/tests/baselines/reference/inheritanceMemberFuncOverridingProperty.js
@@ -23,7 +23,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     b.prototype.x = function () {
         return "20";
diff --git a/tests/baselines/reference/inheritanceMemberPropertyOverridingAccessor.js b/tests/baselines/reference/inheritanceMemberPropertyOverridingAccessor.js
index a8fc4d5a3dd..6895077abda 100644
--- a/tests/baselines/reference/inheritanceMemberPropertyOverridingAccessor.js
+++ b/tests/baselines/reference/inheritanceMemberPropertyOverridingAccessor.js
@@ -37,7 +37,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return b;
 }(a));
diff --git a/tests/baselines/reference/inheritanceMemberPropertyOverridingMethod.js b/tests/baselines/reference/inheritanceMemberPropertyOverridingMethod.js
index 7d5cdb43e96..00c1093053b 100644
--- a/tests/baselines/reference/inheritanceMemberPropertyOverridingMethod.js
+++ b/tests/baselines/reference/inheritanceMemberPropertyOverridingMethod.js
@@ -26,7 +26,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return b;
 }(a));
diff --git a/tests/baselines/reference/inheritanceMemberPropertyOverridingProperty.js b/tests/baselines/reference/inheritanceMemberPropertyOverridingProperty.js
index 648f1d1622e..6cbb7ae7e8c 100644
--- a/tests/baselines/reference/inheritanceMemberPropertyOverridingProperty.js
+++ b/tests/baselines/reference/inheritanceMemberPropertyOverridingProperty.js
@@ -21,7 +21,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return b;
 }(a));
diff --git a/tests/baselines/reference/inheritanceOfGenericConstructorMethod1.js b/tests/baselines/reference/inheritanceOfGenericConstructorMethod1.js
index 59675c56e5f..370e27514c1 100644
--- a/tests/baselines/reference/inheritanceOfGenericConstructorMethod1.js
+++ b/tests/baselines/reference/inheritanceOfGenericConstructorMethod1.js
@@ -21,7 +21,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/inheritanceOfGenericConstructorMethod2.js b/tests/baselines/reference/inheritanceOfGenericConstructorMethod2.js
index 97464233027..a61b6bafabd 100644
--- a/tests/baselines/reference/inheritanceOfGenericConstructorMethod2.js
+++ b/tests/baselines/reference/inheritanceOfGenericConstructorMethod2.js
@@ -40,7 +40,8 @@ var N;
     var D1 = (function (_super) {
         __extends(D1, _super);
         function D1() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D1;
     }(M.C1));
@@ -48,7 +49,8 @@ var N;
     var D2 = (function (_super) {
         __extends(D2, _super);
         function D2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D2;
     }(M.C2));
diff --git a/tests/baselines/reference/inheritanceStaticAccessorOverridingAccessor.js b/tests/baselines/reference/inheritanceStaticAccessorOverridingAccessor.js
index 49145b010d4..9f71208e5db 100644
--- a/tests/baselines/reference/inheritanceStaticAccessorOverridingAccessor.js
+++ b/tests/baselines/reference/inheritanceStaticAccessorOverridingAccessor.js
@@ -40,7 +40,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Object.defineProperty(b, "x", {
         get: function () {
diff --git a/tests/baselines/reference/inheritanceStaticAccessorOverridingMethod.js b/tests/baselines/reference/inheritanceStaticAccessorOverridingMethod.js
index 4a202b76497..2e0c3dc90d0 100644
--- a/tests/baselines/reference/inheritanceStaticAccessorOverridingMethod.js
+++ b/tests/baselines/reference/inheritanceStaticAccessorOverridingMethod.js
@@ -31,7 +31,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Object.defineProperty(b, "x", {
         get: function () {
diff --git a/tests/baselines/reference/inheritanceStaticAccessorOverridingProperty.js b/tests/baselines/reference/inheritanceStaticAccessorOverridingProperty.js
index a0dd1177cfb..95bf94572b1 100644
--- a/tests/baselines/reference/inheritanceStaticAccessorOverridingProperty.js
+++ b/tests/baselines/reference/inheritanceStaticAccessorOverridingProperty.js
@@ -26,7 +26,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Object.defineProperty(b, "x", {
         get: function () {
diff --git a/tests/baselines/reference/inheritanceStaticFuncOverridingAccessor.js b/tests/baselines/reference/inheritanceStaticFuncOverridingAccessor.js
index 06f907371ea..25d75bea5af 100644
--- a/tests/baselines/reference/inheritanceStaticFuncOverridingAccessor.js
+++ b/tests/baselines/reference/inheritanceStaticFuncOverridingAccessor.js
@@ -37,7 +37,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     b.x = function () {
         return "20";
diff --git a/tests/baselines/reference/inheritanceStaticFuncOverridingAccessorOfFuncType.js b/tests/baselines/reference/inheritanceStaticFuncOverridingAccessorOfFuncType.js
index ea36c40480f..5c39c10e738 100644
--- a/tests/baselines/reference/inheritanceStaticFuncOverridingAccessorOfFuncType.js
+++ b/tests/baselines/reference/inheritanceStaticFuncOverridingAccessorOfFuncType.js
@@ -32,7 +32,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     b.x = function () {
         return "20";
diff --git a/tests/baselines/reference/inheritanceStaticFuncOverridingMethod.js b/tests/baselines/reference/inheritanceStaticFuncOverridingMethod.js
index ae523d53d9b..c37caf8d53c 100644
--- a/tests/baselines/reference/inheritanceStaticFuncOverridingMethod.js
+++ b/tests/baselines/reference/inheritanceStaticFuncOverridingMethod.js
@@ -28,7 +28,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     b.x = function () {
         return "20";
diff --git a/tests/baselines/reference/inheritanceStaticFuncOverridingProperty.js b/tests/baselines/reference/inheritanceStaticFuncOverridingProperty.js
index 93890bd8294..eb185d56d0b 100644
--- a/tests/baselines/reference/inheritanceStaticFuncOverridingProperty.js
+++ b/tests/baselines/reference/inheritanceStaticFuncOverridingProperty.js
@@ -23,7 +23,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     b.x = function () {
         return "20";
diff --git a/tests/baselines/reference/inheritanceStaticFuncOverridingPropertyOfFuncType.js b/tests/baselines/reference/inheritanceStaticFuncOverridingPropertyOfFuncType.js
index 4d0f2438459..0779cc10d37 100644
--- a/tests/baselines/reference/inheritanceStaticFuncOverridingPropertyOfFuncType.js
+++ b/tests/baselines/reference/inheritanceStaticFuncOverridingPropertyOfFuncType.js
@@ -23,7 +23,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     b.x = function () {
         return "20";
diff --git a/tests/baselines/reference/inheritanceStaticFunctionOverridingInstanceProperty.js b/tests/baselines/reference/inheritanceStaticFunctionOverridingInstanceProperty.js
index f2dfda4e48f..4934947233f 100644
--- a/tests/baselines/reference/inheritanceStaticFunctionOverridingInstanceProperty.js
+++ b/tests/baselines/reference/inheritanceStaticFunctionOverridingInstanceProperty.js
@@ -23,7 +23,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     b.x = function () {
         return new b().x;
diff --git a/tests/baselines/reference/inheritanceStaticMembersCompatible.js b/tests/baselines/reference/inheritanceStaticMembersCompatible.js
index 0dc736a375d..27a65d513fd 100644
--- a/tests/baselines/reference/inheritanceStaticMembersCompatible.js
+++ b/tests/baselines/reference/inheritanceStaticMembersCompatible.js
@@ -21,7 +21,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return b;
 }(a));
diff --git a/tests/baselines/reference/inheritanceStaticMembersIncompatible.js b/tests/baselines/reference/inheritanceStaticMembersIncompatible.js
index 51c474430ad..7cfafdf1f9d 100644
--- a/tests/baselines/reference/inheritanceStaticMembersIncompatible.js
+++ b/tests/baselines/reference/inheritanceStaticMembersIncompatible.js
@@ -21,7 +21,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return b;
 }(a));
diff --git a/tests/baselines/reference/inheritanceStaticPropertyOverridingAccessor.js b/tests/baselines/reference/inheritanceStaticPropertyOverridingAccessor.js
index d138ac3eba8..1840a7829e8 100644
--- a/tests/baselines/reference/inheritanceStaticPropertyOverridingAccessor.js
+++ b/tests/baselines/reference/inheritanceStaticPropertyOverridingAccessor.js
@@ -36,7 +36,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return b;
 }(a));
diff --git a/tests/baselines/reference/inheritanceStaticPropertyOverridingMethod.js b/tests/baselines/reference/inheritanceStaticPropertyOverridingMethod.js
index 3d3f550713e..8e498273b86 100644
--- a/tests/baselines/reference/inheritanceStaticPropertyOverridingMethod.js
+++ b/tests/baselines/reference/inheritanceStaticPropertyOverridingMethod.js
@@ -26,7 +26,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return b;
 }(a));
diff --git a/tests/baselines/reference/inheritanceStaticPropertyOverridingProperty.js b/tests/baselines/reference/inheritanceStaticPropertyOverridingProperty.js
index e23917e40a4..c003eaa60b4 100644
--- a/tests/baselines/reference/inheritanceStaticPropertyOverridingProperty.js
+++ b/tests/baselines/reference/inheritanceStaticPropertyOverridingProperty.js
@@ -21,7 +21,8 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return b;
 }(a));
diff --git a/tests/baselines/reference/inheritedConstructorWithRestParams.js b/tests/baselines/reference/inheritedConstructorWithRestParams.js
index 2d312d9859d..ca6a379816f 100644
--- a/tests/baselines/reference/inheritedConstructorWithRestParams.js
+++ b/tests/baselines/reference/inheritedConstructorWithRestParams.js
@@ -32,7 +32,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/inheritedConstructorWithRestParams2.js b/tests/baselines/reference/inheritedConstructorWithRestParams2.js
index 0ad25b302f0..b323aefbd48 100644
--- a/tests/baselines/reference/inheritedConstructorWithRestParams2.js
+++ b/tests/baselines/reference/inheritedConstructorWithRestParams2.js
@@ -53,14 +53,16 @@ var BaseBase2 = (function () {
 var Base = (function (_super) {
     __extends(Base, _super);
     function Base() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Base;
 }(BaseBase));
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/inheritedModuleMembersForClodule.js b/tests/baselines/reference/inheritedModuleMembersForClodule.js
index 95b71069584..1de6f5f638a 100644
--- a/tests/baselines/reference/inheritedModuleMembersForClodule.js
+++ b/tests/baselines/reference/inheritedModuleMembersForClodule.js
@@ -38,7 +38,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(C));
@@ -53,7 +54,8 @@ var D;
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     E.bar = function () {
         return this.foo();
diff --git a/tests/baselines/reference/instanceOfAssignability.js b/tests/baselines/reference/instanceOfAssignability.js
index 775afe86946..f78378f0885 100644
--- a/tests/baselines/reference/instanceOfAssignability.js
+++ b/tests/baselines/reference/instanceOfAssignability.js
@@ -115,14 +115,16 @@ var Animal = (function () {
 var Mammal = (function (_super) {
     __extends(Mammal, _super);
     function Mammal() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Mammal;
 }(Animal));
 var Giraffe = (function (_super) {
     __extends(Giraffe, _super);
     function Giraffe() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Giraffe;
 }(Mammal));
diff --git a/tests/baselines/reference/instancePropertiesInheritedIntoClassType.js b/tests/baselines/reference/instancePropertiesInheritedIntoClassType.js
index a507a19a456..cf056e768d8 100644
--- a/tests/baselines/reference/instancePropertiesInheritedIntoClassType.js
+++ b/tests/baselines/reference/instancePropertiesInheritedIntoClassType.js
@@ -69,7 +69,8 @@ var NonGeneric;
     var D = (function (_super) {
         __extends(D, _super);
         function D() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D;
     }(C));
@@ -101,7 +102,8 @@ var Generic;
     var D = (function (_super) {
         __extends(D, _super);
         function D() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D;
     }(C));
diff --git a/tests/baselines/reference/instanceSubtypeCheck2.js b/tests/baselines/reference/instanceSubtypeCheck2.js
index d72f29e93bf..e70dc7b6481 100644
--- a/tests/baselines/reference/instanceSubtypeCheck2.js
+++ b/tests/baselines/reference/instanceSubtypeCheck2.js
@@ -21,7 +21,8 @@ var C1 = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }(C1));
diff --git a/tests/baselines/reference/instanceofWithStructurallyIdenticalTypes.js b/tests/baselines/reference/instanceofWithStructurallyIdenticalTypes.js
index 97be2137722..de2789caa68 100644
--- a/tests/baselines/reference/instanceofWithStructurallyIdenticalTypes.js
+++ b/tests/baselines/reference/instanceofWithStructurallyIdenticalTypes.js
@@ -128,7 +128,8 @@ var A = (function () {
 var A1 = (function (_super) {
     __extends(A1, _super);
     function A1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return A1;
 }(A));
@@ -140,7 +141,8 @@ var A2 = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/instantiatedReturnTypeContravariance.js b/tests/baselines/reference/instantiatedReturnTypeContravariance.js
index 4d5e4376308..83ad38e64f0 100644
--- a/tests/baselines/reference/instantiatedReturnTypeContravariance.js
+++ b/tests/baselines/reference/instantiatedReturnTypeContravariance.js
@@ -47,7 +47,8 @@ var c = (function () {
 var d = (function (_super) {
     __extends(d, _super);
     function d() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     d.prototype.foo = function () {
         return null;
diff --git a/tests/baselines/reference/interfaceClassMerging.js b/tests/baselines/reference/interfaceClassMerging.js
index 8138e7888b3..6111e7f8cee 100644
--- a/tests/baselines/reference/interfaceClassMerging.js
+++ b/tests/baselines/reference/interfaceClassMerging.js
@@ -57,7 +57,8 @@ var Foo = (function () {
 var Bar = (function (_super) {
     __extends(Bar, _super);
     function Bar() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Bar.prototype.method = function (a) {
         return this.optionalProperty;
diff --git a/tests/baselines/reference/interfaceClassMerging2.js b/tests/baselines/reference/interfaceClassMerging2.js
index 99f5b07696d..499bd219905 100644
--- a/tests/baselines/reference/interfaceClassMerging2.js
+++ b/tests/baselines/reference/interfaceClassMerging2.js
@@ -53,7 +53,8 @@ var Foo = (function () {
 var Bar = (function (_super) {
     __extends(Bar, _super);
     function Bar() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Bar.prototype.classBarMethod = function () {
         return this;
diff --git a/tests/baselines/reference/interfaceExtendsClass1.js b/tests/baselines/reference/interfaceExtendsClass1.js
index 43c7c6f6fa4..70ceaa8acd3 100644
--- a/tests/baselines/reference/interfaceExtendsClass1.js
+++ b/tests/baselines/reference/interfaceExtendsClass1.js
@@ -32,7 +32,8 @@ var Control = (function () {
 var Button = (function (_super) {
     __extends(Button, _super);
     function Button() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Button.prototype.select = function () { };
     return Button;
@@ -40,7 +41,8 @@ var Button = (function (_super) {
 var TextBox = (function (_super) {
     __extends(TextBox, _super);
     function TextBox() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     TextBox.prototype.select = function () { };
     return TextBox;
@@ -48,7 +50,8 @@ var TextBox = (function (_super) {
 var Image = (function (_super) {
     __extends(Image, _super);
     function Image() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Image;
 }(Control));
diff --git a/tests/baselines/reference/interfaceExtendsClassWithPrivate1.js b/tests/baselines/reference/interfaceExtendsClassWithPrivate1.js
index e1bdbff85dd..5e6695dd200 100644
--- a/tests/baselines/reference/interfaceExtendsClassWithPrivate1.js
+++ b/tests/baselines/reference/interfaceExtendsClassWithPrivate1.js
@@ -43,7 +43,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     D.prototype.foo = function (x) { return x; };
     D.prototype.other = function (x) { return x; };
diff --git a/tests/baselines/reference/interfaceExtendsClassWithPrivate2.js b/tests/baselines/reference/interfaceExtendsClassWithPrivate2.js
index 1592b1a723b..6f35c3f0e40 100644
--- a/tests/baselines/reference/interfaceExtendsClassWithPrivate2.js
+++ b/tests/baselines/reference/interfaceExtendsClassWithPrivate2.js
@@ -39,7 +39,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.x = 2;
         this.y = 3;
     }
@@ -51,7 +52,8 @@ var D = (function (_super) {
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.x = "";
     }
     D2.prototype.foo = function (x) { return x; };
diff --git a/tests/baselines/reference/interfaceImplementation8.js b/tests/baselines/reference/interfaceImplementation8.js
index edfb33bfe1b..f3bfa4db6a5 100644
--- a/tests/baselines/reference/interfaceImplementation8.js
+++ b/tests/baselines/reference/interfaceImplementation8.js
@@ -64,21 +64,24 @@ var C3 = (function () {
 var C4 = (function (_super) {
     __extends(C4, _super);
     function C4() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C4;
 }(C1));
 var C5 = (function (_super) {
     __extends(C5, _super);
     function C5() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C5;
 }(C2));
 var C6 = (function (_super) {
     __extends(C6, _super);
     function C6() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C6;
 }(C3));
@@ -90,7 +93,8 @@ var C7 = (function () {
 var C8 = (function (_super) {
     __extends(C8, _super);
     function C8() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C8;
 }(C7));
diff --git a/tests/baselines/reference/invalidModuleWithStatementsOfEveryKind.js b/tests/baselines/reference/invalidModuleWithStatementsOfEveryKind.js
index cb3c22b52eb..75bf3f91884 100644
--- a/tests/baselines/reference/invalidModuleWithStatementsOfEveryKind.js
+++ b/tests/baselines/reference/invalidModuleWithStatementsOfEveryKind.js
@@ -95,7 +95,8 @@ var Y;
     var BB = (function (_super) {
         __extends(BB, _super);
         function BB() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return BB;
     }(A));
@@ -110,7 +111,8 @@ var Y2;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(AA));
@@ -144,7 +146,8 @@ var YY;
     var BB = (function (_super) {
         __extends(BB, _super);
         function BB() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return BB;
     }(A));
@@ -159,7 +162,8 @@ var YY2;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(AA));
@@ -193,7 +197,8 @@ var YYY;
     var BB = (function (_super) {
         __extends(BB, _super);
         function BB() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return BB;
     }(A));
@@ -208,7 +213,8 @@ var YYY2;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(AA));
diff --git a/tests/baselines/reference/invalidMultipleVariableDeclarations.js b/tests/baselines/reference/invalidMultipleVariableDeclarations.js
index 0c90c6d0025..b4fbd6f3698 100644
--- a/tests/baselines/reference/invalidMultipleVariableDeclarations.js
+++ b/tests/baselines/reference/invalidMultipleVariableDeclarations.js
@@ -67,7 +67,8 @@ var C = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }(C));
diff --git a/tests/baselines/reference/invalidReturnStatements.js b/tests/baselines/reference/invalidReturnStatements.js
index 0f5b0d3e08d..1409b1c59a8 100644
--- a/tests/baselines/reference/invalidReturnStatements.js
+++ b/tests/baselines/reference/invalidReturnStatements.js
@@ -41,7 +41,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/isolatedModulesImportExportElision.js b/tests/baselines/reference/isolatedModulesImportExportElision.js
index 2d391a64fe7..baf2d1de129 100644
--- a/tests/baselines/reference/isolatedModulesImportExportElision.js
+++ b/tests/baselines/reference/isolatedModulesImportExportElision.js
@@ -26,7 +26,8 @@ var ns = require("module");
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(module_2.c2.C));
diff --git a/tests/baselines/reference/jsxViaImport.js b/tests/baselines/reference/jsxViaImport.js
index 63c84090c9c..c149d4e3c3d 100644
--- a/tests/baselines/reference/jsxViaImport.js
+++ b/tests/baselines/reference/jsxViaImport.js
@@ -35,7 +35,8 @@ var BaseComponent = require("BaseComponent");
 var TestComponent = (function (_super) {
     __extends(TestComponent, _super);
     function TestComponent() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     TestComponent.prototype.render = function () {
         return <BaseComponent />;
diff --git a/tests/baselines/reference/lambdaArgCrash.js b/tests/baselines/reference/lambdaArgCrash.js
index 822aa71efd0..16653cfb4f3 100644
--- a/tests/baselines/reference/lambdaArgCrash.js
+++ b/tests/baselines/reference/lambdaArgCrash.js
@@ -56,7 +56,8 @@ var Event = (function () {
 var ItemSetEvent = (function (_super) {
     __extends(ItemSetEvent, _super);
     function ItemSetEvent() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     ItemSetEvent.prototype.add = function (listener) {
         _super.prototype.add.call(this, listener);
diff --git a/tests/baselines/reference/lift.js b/tests/baselines/reference/lift.js
index 568379948bc..bfbf75b1731 100644
--- a/tests/baselines/reference/lift.js
+++ b/tests/baselines/reference/lift.js
@@ -32,7 +32,8 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C(y, z, w) {
-        _super.call(this, y);
+        var _this;
+        _this = _super.call(this, y) || this;
         var x = 10 + w;
         var ll = x * w;
     }
diff --git a/tests/baselines/reference/localTypes1.js b/tests/baselines/reference/localTypes1.js
index a4f835c8669..96c9337817d 100644
--- a/tests/baselines/reference/localTypes1.js
+++ b/tests/baselines/reference/localTypes1.js
@@ -300,7 +300,8 @@ function f6() {
         var B = (function (_super) {
             __extends(B, _super);
             function B() {
-                _super.apply(this, arguments);
+                var _this = _super.apply(this, arguments) || this;
+                return _this;
             }
             return B;
         }(A));
@@ -308,7 +309,8 @@ function f6() {
             var C = (function (_super) {
                 __extends(C, _super);
                 function C() {
-                    _super.apply(this, arguments);
+                    var _this = _super.apply(this, arguments) || this;
+                    return _this;
                 }
                 return C;
             }(B));
diff --git a/tests/baselines/reference/m7Bugs.js b/tests/baselines/reference/m7Bugs.js
index 6292356faf5..19cd9ee4630 100644
--- a/tests/baselines/reference/m7Bugs.js
+++ b/tests/baselines/reference/m7Bugs.js
@@ -42,7 +42,8 @@ var C1 = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }(C1));
diff --git a/tests/baselines/reference/mergedDeclarations5.js b/tests/baselines/reference/mergedDeclarations5.js
index ce4b929c7f9..53a8c983399 100644
--- a/tests/baselines/reference/mergedDeclarations5.js
+++ b/tests/baselines/reference/mergedDeclarations5.js
@@ -27,7 +27,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     B.prototype.foo = function () { };
     return B;
diff --git a/tests/baselines/reference/mergedDeclarations6.js b/tests/baselines/reference/mergedDeclarations6.js
index 2ff9d3e6604..50108773a70 100644
--- a/tests/baselines/reference/mergedDeclarations6.js
+++ b/tests/baselines/reference/mergedDeclarations6.js
@@ -47,7 +47,8 @@ define(["require", "exports", "./a"], function (require, exports, a_1) {
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         B.prototype.setProtected = function () {
         };
diff --git a/tests/baselines/reference/mergedInheritedClassInterface.js b/tests/baselines/reference/mergedInheritedClassInterface.js
index 72ac1c8a928..fd0bea5494c 100644
--- a/tests/baselines/reference/mergedInheritedClassInterface.js
+++ b/tests/baselines/reference/mergedInheritedClassInterface.js
@@ -61,7 +61,8 @@ var BaseClass = (function () {
 var Child = (function (_super) {
     __extends(Child, _super);
     function Child() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Child.prototype.method = function () { };
     return Child;
@@ -75,7 +76,8 @@ var ChildNoBaseClass = (function () {
 var Grandchild = (function (_super) {
     __extends(Grandchild, _super);
     function Grandchild() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Grandchild;
 }(ChildNoBaseClass));
diff --git a/tests/baselines/reference/mergedInterfacesWithInheritedPrivates2.js b/tests/baselines/reference/mergedInterfacesWithInheritedPrivates2.js
index a7e341c31ce..a3baa1920e3 100644
--- a/tests/baselines/reference/mergedInterfacesWithInheritedPrivates2.js
+++ b/tests/baselines/reference/mergedInterfacesWithInheritedPrivates2.js
@@ -50,14 +50,16 @@ var C2 = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(C));
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return E;
 }(C2));
diff --git a/tests/baselines/reference/mergedInterfacesWithInheritedPrivates3.js b/tests/baselines/reference/mergedInterfacesWithInheritedPrivates3.js
index 3d9c4e1175e..e21ca151c87 100644
--- a/tests/baselines/reference/mergedInterfacesWithInheritedPrivates3.js
+++ b/tests/baselines/reference/mergedInterfacesWithInheritedPrivates3.js
@@ -57,7 +57,8 @@ var C2 = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/missingPropertiesOfClassExpression.js b/tests/baselines/reference/missingPropertiesOfClassExpression.js
index 54834397b64..c1f4480241c 100644
--- a/tests/baselines/reference/missingPropertiesOfClassExpression.js
+++ b/tests/baselines/reference/missingPropertiesOfClassExpression.js
@@ -15,7 +15,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var George = (function (_super) {
     __extends(George, _super);
     function George() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
     }
     return George;
 }((function () {
diff --git a/tests/baselines/reference/moduleAsBaseType.js b/tests/baselines/reference/moduleAsBaseType.js
index 71f16846363..598ddaef2de 100644
--- a/tests/baselines/reference/moduleAsBaseType.js
+++ b/tests/baselines/reference/moduleAsBaseType.js
@@ -13,7 +13,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(M));
diff --git a/tests/baselines/reference/moduleImportedForTypeArgumentPosition.js b/tests/baselines/reference/moduleImportedForTypeArgumentPosition.js
index cd2df2633ae..2f4ac430cc1 100644
--- a/tests/baselines/reference/moduleImportedForTypeArgumentPosition.js
+++ b/tests/baselines/reference/moduleImportedForTypeArgumentPosition.js
@@ -31,7 +31,8 @@ define(["require", "exports"], function (require, exports) {
     var Test1 = (function (_super) {
         __extends(Test1, _super);
         function Test1() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Test1;
     }(C1));
diff --git a/tests/baselines/reference/moduleWithStatementsOfEveryKind.js b/tests/baselines/reference/moduleWithStatementsOfEveryKind.js
index ec434286f43..11053d76d2d 100644
--- a/tests/baselines/reference/moduleWithStatementsOfEveryKind.js
+++ b/tests/baselines/reference/moduleWithStatementsOfEveryKind.js
@@ -79,14 +79,16 @@ var A;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(AA));
     var BB = (function (_super) {
         __extends(BB, _super);
         function BB() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return BB;
     }(A));
@@ -130,7 +132,8 @@ var Y;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(AA));
@@ -138,7 +141,8 @@ var Y;
     var BB = (function (_super) {
         __extends(BB, _super);
         function BB() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return BB;
     }(A));
diff --git a/tests/baselines/reference/multipleInheritance.js b/tests/baselines/reference/multipleInheritance.js
index 26372bfb718..80e9a469398 100644
--- a/tests/baselines/reference/multipleInheritance.js
+++ b/tests/baselines/reference/multipleInheritance.js
@@ -57,28 +57,32 @@ var B2 = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(B1));
 var D1 = (function (_super) {
     __extends(D1, _super);
     function D1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D1;
 }(B1));
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D2;
 }(B2));
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return E;
 }(D1));
@@ -90,7 +94,8 @@ var N = (function () {
 var ND = (function (_super) {
     __extends(ND, _super);
     function ND() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return ND;
 }(N));
@@ -104,7 +109,8 @@ var Good = (function () {
 var Baad = (function (_super) {
     __extends(Baad, _super);
     function Baad() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Baad.prototype.f = function () { return 0; };
     Baad.prototype.g = function (n) { return 0; };
diff --git a/tests/baselines/reference/mutuallyRecursiveGenericBaseTypes2.js b/tests/baselines/reference/mutuallyRecursiveGenericBaseTypes2.js
index c8cca671327..7c5ec66c6be 100644
--- a/tests/baselines/reference/mutuallyRecursiveGenericBaseTypes2.js
+++ b/tests/baselines/reference/mutuallyRecursiveGenericBaseTypes2.js
@@ -25,7 +25,8 @@ var foo = (function () {
 var foo2 = (function (_super) {
     __extends(foo2, _super);
     function foo2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return foo2;
 }(foo));
diff --git a/tests/baselines/reference/noEmitHelpers.js b/tests/baselines/reference/noEmitHelpers.js
index b2c26c6af75..c3d27cac8a9 100644
--- a/tests/baselines/reference/noEmitHelpers.js
+++ b/tests/baselines/reference/noEmitHelpers.js
@@ -13,7 +13,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/nonGenericClassExtendingGenericClassWithAny.js b/tests/baselines/reference/nonGenericClassExtendingGenericClassWithAny.js
index b9927ebf193..bbab8e9ccdd 100644
--- a/tests/baselines/reference/nonGenericClassExtendingGenericClassWithAny.js
+++ b/tests/baselines/reference/nonGenericClassExtendingGenericClassWithAny.js
@@ -19,7 +19,8 @@ var Foo = (function () {
 var Bar = (function (_super) {
     __extends(Bar, _super);
     function Bar() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Bar;
 }(Foo)); // Valid
diff --git a/tests/baselines/reference/numericIndexerConstrainsPropertyDeclarations2.js b/tests/baselines/reference/numericIndexerConstrainsPropertyDeclarations2.js
index cef2759e1d5..1901e169447 100644
--- a/tests/baselines/reference/numericIndexerConstrainsPropertyDeclarations2.js
+++ b/tests/baselines/reference/numericIndexerConstrainsPropertyDeclarations2.js
@@ -61,7 +61,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     B.prototype.bar = function () { return ''; };
     return B;
diff --git a/tests/baselines/reference/numericIndexerConstraint3.js b/tests/baselines/reference/numericIndexerConstraint3.js
index 9f7a61fe30d..97c3e56d423 100644
--- a/tests/baselines/reference/numericIndexerConstraint3.js
+++ b/tests/baselines/reference/numericIndexerConstraint3.js
@@ -26,7 +26,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/numericIndexerConstraint4.js b/tests/baselines/reference/numericIndexerConstraint4.js
index a9eace23833..732f7e2672c 100644
--- a/tests/baselines/reference/numericIndexerConstraint4.js
+++ b/tests/baselines/reference/numericIndexerConstraint4.js
@@ -26,7 +26,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/numericIndexerTyping2.js b/tests/baselines/reference/numericIndexerTyping2.js
index 47fb46794f0..1d38f844384 100644
--- a/tests/baselines/reference/numericIndexerTyping2.js
+++ b/tests/baselines/reference/numericIndexerTyping2.js
@@ -26,7 +26,8 @@ var I = (function () {
 var I2 = (function (_super) {
     __extends(I2, _super);
     function I2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return I2;
 }(I));
diff --git a/tests/baselines/reference/objectCreationOfElementAccessExpression.js b/tests/baselines/reference/objectCreationOfElementAccessExpression.js
index dce09972c83..ddfbce8fc12 100644
--- a/tests/baselines/reference/objectCreationOfElementAccessExpression.js
+++ b/tests/baselines/reference/objectCreationOfElementAccessExpression.js
@@ -81,7 +81,8 @@ var Food = (function () {
 var MonsterFood = (function (_super) {
     __extends(MonsterFood, _super);
     function MonsterFood(name, flavor) {
-        _super.call(this, name);
+        var _this;
+        _this = _super.call(this, name) || this;
         this.flavor = flavor;
     }
     return MonsterFood;
@@ -89,7 +90,8 @@ var MonsterFood = (function (_super) {
 var IceCream = (function (_super) {
     __extends(IceCream, _super);
     function IceCream(flavor) {
-        _super.call(this, "Ice Cream", flavor);
+        var _this;
+        _this = _super.call(this, "Ice Cream", flavor) || this;
         this.flavor = flavor;
     }
     return IceCream;
@@ -97,7 +99,8 @@ var IceCream = (function (_super) {
 var Cookie = (function (_super) {
     __extends(Cookie, _super);
     function Cookie(flavor, isGlutenFree) {
-        _super.call(this, "Cookie", flavor);
+        var _this;
+        _this = _super.call(this, "Cookie", flavor) || this;
         this.flavor = flavor;
         this.isGlutenFree = isGlutenFree;
     }
@@ -106,7 +109,8 @@ var Cookie = (function (_super) {
 var PetFood = (function (_super) {
     __extends(PetFood, _super);
     function PetFood(name, whereToBuy) {
-        _super.call(this, name);
+        var _this;
+        _this = _super.call(this, name) || this;
         this.whereToBuy = whereToBuy;
     }
     return PetFood;
@@ -114,7 +118,8 @@ var PetFood = (function (_super) {
 var ExpensiveOrganicDogFood = (function (_super) {
     __extends(ExpensiveOrganicDogFood, _super);
     function ExpensiveOrganicDogFood(whereToBuy) {
-        _super.call(this, "Origen", whereToBuy);
+        var _this;
+        _this = _super.call(this, "Origen", whereToBuy) || this;
         this.whereToBuy = whereToBuy;
     }
     return ExpensiveOrganicDogFood;
@@ -122,7 +127,8 @@ var ExpensiveOrganicDogFood = (function (_super) {
 var ExpensiveOrganicCatFood = (function (_super) {
     __extends(ExpensiveOrganicCatFood, _super);
     function ExpensiveOrganicCatFood(whereToBuy, containsFish) {
-        _super.call(this, "Nature's Logic", whereToBuy);
+        var _this;
+        _this = _super.call(this, "Nature's Logic", whereToBuy) || this;
         this.whereToBuy = whereToBuy;
         this.containsFish = containsFish;
     }
diff --git a/tests/baselines/reference/objectTypeHidingMembersOfExtendedObject.js b/tests/baselines/reference/objectTypeHidingMembersOfExtendedObject.js
index 9c5bcfb8e2d..76c18900945 100644
--- a/tests/baselines/reference/objectTypeHidingMembersOfExtendedObject.js
+++ b/tests/baselines/reference/objectTypeHidingMembersOfExtendedObject.js
@@ -68,7 +68,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/objectTypesIdentityWithNumericIndexers1.js b/tests/baselines/reference/objectTypesIdentityWithNumericIndexers1.js
index 29781229b5a..3df18cb27cb 100644
--- a/tests/baselines/reference/objectTypesIdentityWithNumericIndexers1.js
+++ b/tests/baselines/reference/objectTypesIdentityWithNumericIndexers1.js
@@ -147,14 +147,16 @@ var C = (function () {
 var PA = (function (_super) {
     __extends(PA, _super);
     function PA() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return PA;
 }(A));
 var PB = (function (_super) {
     __extends(PB, _super);
     function PB() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return PB;
 }(B));
diff --git a/tests/baselines/reference/objectTypesIdentityWithNumericIndexers2.js b/tests/baselines/reference/objectTypesIdentityWithNumericIndexers2.js
index 7ecb597a2d9..e7d2f603d5c 100644
--- a/tests/baselines/reference/objectTypesIdentityWithNumericIndexers2.js
+++ b/tests/baselines/reference/objectTypesIdentityWithNumericIndexers2.js
@@ -140,7 +140,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
@@ -162,14 +163,16 @@ var C = (function () {
 var PA = (function (_super) {
     __extends(PA, _super);
     function PA() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return PA;
 }(A));
 var PB = (function (_super) {
     __extends(PB, _super);
     function PB() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return PB;
 }(B));
diff --git a/tests/baselines/reference/objectTypesIdentityWithNumericIndexers3.js b/tests/baselines/reference/objectTypesIdentityWithNumericIndexers3.js
index 9710afe700d..e0b75f54208 100644
--- a/tests/baselines/reference/objectTypesIdentityWithNumericIndexers3.js
+++ b/tests/baselines/reference/objectTypesIdentityWithNumericIndexers3.js
@@ -147,14 +147,16 @@ var C = (function () {
 var PA = (function (_super) {
     __extends(PA, _super);
     function PA() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return PA;
 }(A));
 var PB = (function (_super) {
     __extends(PB, _super);
     function PB() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return PB;
 }(B));
diff --git a/tests/baselines/reference/objectTypesIdentityWithPrivates.js b/tests/baselines/reference/objectTypesIdentityWithPrivates.js
index 7d6be5eaf8f..681af407bd4 100644
--- a/tests/baselines/reference/objectTypesIdentityWithPrivates.js
+++ b/tests/baselines/reference/objectTypesIdentityWithPrivates.js
@@ -145,14 +145,16 @@ var C = (function () {
 var PA = (function (_super) {
     __extends(PA, _super);
     function PA() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return PA;
 }(A));
 var PB = (function (_super) {
     __extends(PB, _super);
     function PB() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return PB;
 }(B));
diff --git a/tests/baselines/reference/objectTypesIdentityWithPrivates2.js b/tests/baselines/reference/objectTypesIdentityWithPrivates2.js
index cb9c677f024..2011b741df2 100644
--- a/tests/baselines/reference/objectTypesIdentityWithPrivates2.js
+++ b/tests/baselines/reference/objectTypesIdentityWithPrivates2.js
@@ -53,7 +53,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/objectTypesIdentityWithPrivates3.js b/tests/baselines/reference/objectTypesIdentityWithPrivates3.js
index 241fbcaf27e..80bdd4c87e1 100644
--- a/tests/baselines/reference/objectTypesIdentityWithPrivates3.js
+++ b/tests/baselines/reference/objectTypesIdentityWithPrivates3.js
@@ -39,7 +39,8 @@ var C1 = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }(C1));
@@ -53,7 +54,8 @@ var C3 = (function () {
 var C4 = (function (_super) {
     __extends(C4, _super);
     function C4() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C4;
 }(C3));
diff --git a/tests/baselines/reference/objectTypesIdentityWithStringIndexers.js b/tests/baselines/reference/objectTypesIdentityWithStringIndexers.js
index c0578c2fba1..3eac80c60fc 100644
--- a/tests/baselines/reference/objectTypesIdentityWithStringIndexers.js
+++ b/tests/baselines/reference/objectTypesIdentityWithStringIndexers.js
@@ -147,14 +147,16 @@ var C = (function () {
 var PA = (function (_super) {
     __extends(PA, _super);
     function PA() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return PA;
 }(A));
 var PB = (function (_super) {
     __extends(PB, _super);
     function PB() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return PB;
 }(B));
diff --git a/tests/baselines/reference/objectTypesIdentityWithStringIndexers2.js b/tests/baselines/reference/objectTypesIdentityWithStringIndexers2.js
index 0670d45a5a5..d55ef5eb28c 100644
--- a/tests/baselines/reference/objectTypesIdentityWithStringIndexers2.js
+++ b/tests/baselines/reference/objectTypesIdentityWithStringIndexers2.js
@@ -140,7 +140,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
@@ -162,14 +163,16 @@ var C = (function () {
 var PA = (function (_super) {
     __extends(PA, _super);
     function PA() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return PA;
 }(A));
 var PB = (function (_super) {
     __extends(PB, _super);
     function PB() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return PB;
 }(B));
diff --git a/tests/baselines/reference/optionalConstructorArgInSuper.js b/tests/baselines/reference/optionalConstructorArgInSuper.js
index 3e6a47b4de2..04056fa9c14 100644
--- a/tests/baselines/reference/optionalConstructorArgInSuper.js
+++ b/tests/baselines/reference/optionalConstructorArgInSuper.js
@@ -25,7 +25,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/optionalMethods.js b/tests/baselines/reference/optionalMethods.js
index 42decf512e4..408f73b6533 100644
--- a/tests/baselines/reference/optionalMethods.js
+++ b/tests/baselines/reference/optionalMethods.js
@@ -109,7 +109,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.a = 1;
     }
     Derived.prototype.f = function () { return 1; };
diff --git a/tests/baselines/reference/optionalParamArgsTest.js b/tests/baselines/reference/optionalParamArgsTest.js
index 6d42c38f907..f53f0c74a54 100644
--- a/tests/baselines/reference/optionalParamArgsTest.js
+++ b/tests/baselines/reference/optionalParamArgsTest.js
@@ -161,8 +161,9 @@ var C1 = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2(v2) {
+        var _this;
         if (v2 === void 0) { v2 = 6; }
-        _super.call(this, v2);
+        _this = _super.call(this, v2) || this;
     }
     return C2;
 }(C1));
diff --git a/tests/baselines/reference/optionalParamInOverride.js b/tests/baselines/reference/optionalParamInOverride.js
index f6ccdbe3fab..a8bd88ed3a8 100644
--- a/tests/baselines/reference/optionalParamInOverride.js
+++ b/tests/baselines/reference/optionalParamInOverride.js
@@ -22,7 +22,8 @@ var Z = (function () {
 var Y = (function (_super) {
     __extends(Y, _super);
     function Y() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Y.prototype.func = function (value) { };
     return Y;
diff --git a/tests/baselines/reference/optionalParameterProperty.js b/tests/baselines/reference/optionalParameterProperty.js
index 48cefeef22c..b23da97c790 100644
--- a/tests/baselines/reference/optionalParameterProperty.js
+++ b/tests/baselines/reference/optionalParameterProperty.js
@@ -25,7 +25,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D(p) {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         this.p = p;
     }
     return D;
diff --git a/tests/baselines/reference/outModuleConcatAmd.js b/tests/baselines/reference/outModuleConcatAmd.js
index 8a478e675c6..5643875efd3 100644
--- a/tests/baselines/reference/outModuleConcatAmd.js
+++ b/tests/baselines/reference/outModuleConcatAmd.js
@@ -28,7 +28,8 @@ define("b", ["require", "exports", "ref/a"], function (require, exports, a_1) {
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(a_1.A));
diff --git a/tests/baselines/reference/outModuleConcatAmd.js.map b/tests/baselines/reference/outModuleConcatAmd.js.map
index 7f9893b2346..25873d9cd07 100644
--- a/tests/baselines/reference/outModuleConcatAmd.js.map
+++ b/tests/baselines/reference/outModuleConcatAmd.js.map
@@ -1,2 +1,2 @@
 //// [all.js.map]
-{"version":3,"file":"all.js","sourceRoot":"","sources":["tests/cases/compiler/ref/a.ts","tests/cases/compiler/b.ts"],"names":[],"mappings":";;;;;;;IACA;QAAA;QAAiB,CAAC;QAAD,QAAC;IAAD,CAAC,AAAlB,IAAkB;IAAlB,cAAkB;;;;ICAlB;QAAuB,qBAAC;QAAxB;YAAuB,8BAAC;QAAG,CAAC;QAAD,QAAC;IAAD,CAAC,AAA5B,CAAuB,KAAC,GAAI;IAA5B,cAA4B"}
\ No newline at end of file
+{"version":3,"file":"all.js","sourceRoot":"","sources":["tests/cases/compiler/ref/a.ts","tests/cases/compiler/b.ts"],"names":[],"mappings":";;;;;;;IACA;QAAA;QAAiB,CAAC;QAAD,QAAC;IAAD,CAAC,AAAlB,IAAkB;IAAlB,cAAkB;;;;ICAlB;QAAuB,qBAAC;QAAxB;YAAuB,kDAAC;;QAAG,CAAC;QAAD,QAAC;IAAD,CAAC,AAA5B,CAAuB,KAAC,GAAI;IAA5B,cAA4B"}
\ No newline at end of file
diff --git a/tests/baselines/reference/outModuleConcatAmd.sourcemap.txt b/tests/baselines/reference/outModuleConcatAmd.sourcemap.txt
index ba7f1d93245..2fa35a323a0 100644
--- a/tests/baselines/reference/outModuleConcatAmd.sourcemap.txt
+++ b/tests/baselines/reference/outModuleConcatAmd.sourcemap.txt
@@ -92,34 +92,35 @@ sourceFile:tests/cases/compiler/b.ts
 ---
 >>>        function B() {
 1 >^^^^^^^^
-2 >        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
+2 >        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
 1 >
 1 >Emitted(19, 9) Source(2, 1) + SourceIndex(1)
 ---
->>>            _super.apply(this, arguments);
+>>>            var _this = _super.apply(this, arguments) || this;
 1->^^^^^^^^^^^^
-2 >            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+2 >            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 1->export class B extends 
 2 >            A
 1->Emitted(20, 13) Source(2, 24) + SourceIndex(1)
-2 >Emitted(20, 43) Source(2, 25) + SourceIndex(1)
+2 >Emitted(20, 63) Source(2, 25) + SourceIndex(1)
 ---
+>>>            return _this;
 >>>        }
 1 >^^^^^^^^
 2 >        ^
 3 >         ^^^^^^^^^->
 1 > { 
 2 >        }
-1 >Emitted(21, 9) Source(2, 28) + SourceIndex(1)
-2 >Emitted(21, 10) Source(2, 29) + SourceIndex(1)
+1 >Emitted(22, 9) Source(2, 28) + SourceIndex(1)
+2 >Emitted(22, 10) Source(2, 29) + SourceIndex(1)
 ---
 >>>        return B;
 1->^^^^^^^^
 2 >        ^^^^^^^^
 1->
 2 >        }
-1->Emitted(22, 9) Source(2, 28) + SourceIndex(1)
-2 >Emitted(22, 17) Source(2, 29) + SourceIndex(1)
+1->Emitted(23, 9) Source(2, 28) + SourceIndex(1)
+2 >Emitted(23, 17) Source(2, 29) + SourceIndex(1)
 ---
 >>>    }(a_1.A));
 1 >^^^^
@@ -135,20 +136,20 @@ sourceFile:tests/cases/compiler/b.ts
 4 >     export class B extends 
 5 >      A
 6 >            { }
-1 >Emitted(23, 5) Source(2, 28) + SourceIndex(1)
-2 >Emitted(23, 6) Source(2, 29) + SourceIndex(1)
-3 >Emitted(23, 6) Source(2, 1) + SourceIndex(1)
-4 >Emitted(23, 7) Source(2, 24) + SourceIndex(1)
-5 >Emitted(23, 12) Source(2, 25) + SourceIndex(1)
-6 >Emitted(23, 15) Source(2, 29) + SourceIndex(1)
+1 >Emitted(24, 5) Source(2, 28) + SourceIndex(1)
+2 >Emitted(24, 6) Source(2, 29) + SourceIndex(1)
+3 >Emitted(24, 6) Source(2, 1) + SourceIndex(1)
+4 >Emitted(24, 7) Source(2, 24) + SourceIndex(1)
+5 >Emitted(24, 12) Source(2, 25) + SourceIndex(1)
+6 >Emitted(24, 15) Source(2, 29) + SourceIndex(1)
 ---
 >>>    exports.B = B;
 1->^^^^
 2 >    ^^^^^^^^^^^^^^
 1->
 2 >    export class B extends A { }
-1->Emitted(24, 5) Source(2, 1) + SourceIndex(1)
-2 >Emitted(24, 19) Source(2, 29) + SourceIndex(1)
+1->Emitted(25, 5) Source(2, 1) + SourceIndex(1)
+2 >Emitted(25, 19) Source(2, 29) + SourceIndex(1)
 ---
 >>>});
 >>>//# sourceMappingURL=all.js.map
\ No newline at end of file
diff --git a/tests/baselines/reference/outModuleConcatSystem.js b/tests/baselines/reference/outModuleConcatSystem.js
index b23b73caf83..eecb4101958 100644
--- a/tests/baselines/reference/outModuleConcatSystem.js
+++ b/tests/baselines/reference/outModuleConcatSystem.js
@@ -44,7 +44,8 @@ System.register("b", ["ref/a"], function (exports_2, context_2) {
             B = (function (_super) {
                 __extends(B, _super);
                 function B() {
-                    _super.apply(this, arguments);
+                    var _this = _super.apply(this, arguments) || this;
+                    return _this;
                 }
                 return B;
             }(a_1.A));
diff --git a/tests/baselines/reference/outModuleConcatSystem.js.map b/tests/baselines/reference/outModuleConcatSystem.js.map
index 59ab70de531..f77bed44ffc 100644
--- a/tests/baselines/reference/outModuleConcatSystem.js.map
+++ b/tests/baselines/reference/outModuleConcatSystem.js.map
@@ -1,2 +1,2 @@
 //// [all.js.map]
-{"version":3,"file":"all.js","sourceRoot":"","sources":["tests/cases/compiler/ref/a.ts","tests/cases/compiler/b.ts"],"names":[],"mappings":";;;;;;;;;;;;YACA;gBAAA;gBAAiB,CAAC;gBAAD,QAAC;YAAD,CAAC,AAAlB,IAAkB;;QAClB,CAAC;;;;;;;;;;;;;;YCDD;gBAAuB,qBAAC;gBAAxB;oBAAuB,8BAAC;gBAAG,CAAC;gBAAD,QAAC;YAAD,CAAC,AAA5B,CAAuB,KAAC,GAAI;;QAAA,CAAC"}
\ No newline at end of file
+{"version":3,"file":"all.js","sourceRoot":"","sources":["tests/cases/compiler/ref/a.ts","tests/cases/compiler/b.ts"],"names":[],"mappings":";;;;;;;;;;;;YACA;gBAAA;gBAAiB,CAAC;gBAAD,QAAC;YAAD,CAAC,AAAlB,IAAkB;;QAClB,CAAC;;;;;;;;;;;;;;YCDD;gBAAuB,qBAAC;gBAAxB;oBAAuB,kDAAC;;gBAAG,CAAC;gBAAD,QAAC;YAAD,CAAC,AAA5B,CAAuB,KAAC,GAAI;;QAAA,CAAC"}
\ No newline at end of file
diff --git a/tests/baselines/reference/outModuleConcatSystem.sourcemap.txt b/tests/baselines/reference/outModuleConcatSystem.sourcemap.txt
index 86573493e20..5287a760ac8 100644
--- a/tests/baselines/reference/outModuleConcatSystem.sourcemap.txt
+++ b/tests/baselines/reference/outModuleConcatSystem.sourcemap.txt
@@ -109,34 +109,35 @@ sourceFile:tests/cases/compiler/b.ts
 ---
 >>>                function B() {
 1 >^^^^^^^^^^^^^^^^
-2 >                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
+2 >                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
 1 >
 1 >Emitted(35, 17) Source(2, 1) + SourceIndex(1)
 ---
->>>                    _super.apply(this, arguments);
+>>>                    var _this = _super.apply(this, arguments) || this;
 1->^^^^^^^^^^^^^^^^^^^^
-2 >                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+2 >                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 1->export class B extends 
 2 >                    A
 1->Emitted(36, 21) Source(2, 24) + SourceIndex(1)
-2 >Emitted(36, 51) Source(2, 25) + SourceIndex(1)
+2 >Emitted(36, 71) Source(2, 25) + SourceIndex(1)
 ---
+>>>                    return _this;
 >>>                }
 1 >^^^^^^^^^^^^^^^^
 2 >                ^
 3 >                 ^^^^^^^^^->
 1 > { 
 2 >                }
-1 >Emitted(37, 17) Source(2, 28) + SourceIndex(1)
-2 >Emitted(37, 18) Source(2, 29) + SourceIndex(1)
+1 >Emitted(38, 17) Source(2, 28) + SourceIndex(1)
+2 >Emitted(38, 18) Source(2, 29) + SourceIndex(1)
 ---
 >>>                return B;
 1->^^^^^^^^^^^^^^^^
 2 >                ^^^^^^^^
 1->
 2 >                }
-1->Emitted(38, 17) Source(2, 28) + SourceIndex(1)
-2 >Emitted(38, 25) Source(2, 29) + SourceIndex(1)
+1->Emitted(39, 17) Source(2, 28) + SourceIndex(1)
+2 >Emitted(39, 25) Source(2, 29) + SourceIndex(1)
 ---
 >>>            }(a_1.A));
 1 >^^^^^^^^^^^^
@@ -152,12 +153,12 @@ sourceFile:tests/cases/compiler/b.ts
 4 >             export class B extends 
 5 >              A
 6 >                    { }
-1 >Emitted(39, 13) Source(2, 28) + SourceIndex(1)
-2 >Emitted(39, 14) Source(2, 29) + SourceIndex(1)
-3 >Emitted(39, 14) Source(2, 1) + SourceIndex(1)
-4 >Emitted(39, 15) Source(2, 24) + SourceIndex(1)
-5 >Emitted(39, 20) Source(2, 25) + SourceIndex(1)
-6 >Emitted(39, 23) Source(2, 29) + SourceIndex(1)
+1 >Emitted(40, 13) Source(2, 28) + SourceIndex(1)
+2 >Emitted(40, 14) Source(2, 29) + SourceIndex(1)
+3 >Emitted(40, 14) Source(2, 1) + SourceIndex(1)
+4 >Emitted(40, 15) Source(2, 24) + SourceIndex(1)
+5 >Emitted(40, 20) Source(2, 25) + SourceIndex(1)
+6 >Emitted(40, 23) Source(2, 29) + SourceIndex(1)
 ---
 >>>            exports_2("B", B);
 >>>        }
@@ -165,8 +166,8 @@ sourceFile:tests/cases/compiler/b.ts
 2 >        ^
 1->
 2 >        
-1->Emitted(41, 9) Source(2, 29) + SourceIndex(1)
-2 >Emitted(41, 10) Source(2, 30) + SourceIndex(1)
+1->Emitted(42, 9) Source(2, 29) + SourceIndex(1)
+2 >Emitted(42, 10) Source(2, 30) + SourceIndex(1)
 ---
 >>>    };
 >>>});
diff --git a/tests/baselines/reference/outModuleTripleSlashRefs.js b/tests/baselines/reference/outModuleTripleSlashRefs.js
index 90f8feab7bc..ac2f2510b64 100644
--- a/tests/baselines/reference/outModuleTripleSlashRefs.js
+++ b/tests/baselines/reference/outModuleTripleSlashRefs.js
@@ -57,7 +57,8 @@ define("b", ["require", "exports", "ref/a"], function (require, exports, a_1) {
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(a_1.A));
diff --git a/tests/baselines/reference/outModuleTripleSlashRefs.js.map b/tests/baselines/reference/outModuleTripleSlashRefs.js.map
index c6e1aab6bc8..1cdbef49afa 100644
--- a/tests/baselines/reference/outModuleTripleSlashRefs.js.map
+++ b/tests/baselines/reference/outModuleTripleSlashRefs.js.map
@@ -1,2 +1,2 @@
 //// [all.js.map]
-{"version":3,"file":"all.js","sourceRoot":"","sources":["tests/cases/compiler/ref/b.ts","tests/cases/compiler/ref/a.ts","tests/cases/compiler/b.ts"],"names":[],"mappings":";;;;;AAAA,iCAAiC;AACjC;IAAA;IAEA,CAAC;IAAD,UAAC;AAAD,CAAC,AAFD,IAEC;;;ICFD,+BAA+B;IAC/B;QAAA;QAEA,CAAC;QAAD,QAAC;IAAD,CAAC,AAFD,IAEC;IAFD,cAEC;;;;ICHD;QAAuB,qBAAC;QAAxB;YAAuB,8BAAC;QAAG,CAAC;QAAD,QAAC;IAAD,CAAC,AAA5B,CAAuB,KAAC,GAAI;IAA5B,cAA4B"}
\ No newline at end of file
+{"version":3,"file":"all.js","sourceRoot":"","sources":["tests/cases/compiler/ref/b.ts","tests/cases/compiler/ref/a.ts","tests/cases/compiler/b.ts"],"names":[],"mappings":";;;;;AAAA,iCAAiC;AACjC;IAAA;IAEA,CAAC;IAAD,UAAC;AAAD,CAAC,AAFD,IAEC;;;ICFD,+BAA+B;IAC/B;QAAA;QAEA,CAAC;QAAD,QAAC;IAAD,CAAC,AAFD,IAEC;IAFD,cAEC;;;;ICHD;QAAuB,qBAAC;QAAxB;YAAuB,kDAAC;;QAAG,CAAC;QAAD,QAAC;IAAD,CAAC,AAA5B,CAAuB,KAAC,GAAI;IAA5B,cAA4B"}
\ No newline at end of file
diff --git a/tests/baselines/reference/outModuleTripleSlashRefs.sourcemap.txt b/tests/baselines/reference/outModuleTripleSlashRefs.sourcemap.txt
index 8be43826419..e940429a74b 100644
--- a/tests/baselines/reference/outModuleTripleSlashRefs.sourcemap.txt
+++ b/tests/baselines/reference/outModuleTripleSlashRefs.sourcemap.txt
@@ -168,34 +168,35 @@ sourceFile:tests/cases/compiler/b.ts
 ---
 >>>        function B() {
 1 >^^^^^^^^
-2 >        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
+2 >        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
 1 >
 1 >Emitted(26, 9) Source(2, 1) + SourceIndex(2)
 ---
->>>            _super.apply(this, arguments);
+>>>            var _this = _super.apply(this, arguments) || this;
 1->^^^^^^^^^^^^
-2 >            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+2 >            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 1->export class B extends 
 2 >            A
 1->Emitted(27, 13) Source(2, 24) + SourceIndex(2)
-2 >Emitted(27, 43) Source(2, 25) + SourceIndex(2)
+2 >Emitted(27, 63) Source(2, 25) + SourceIndex(2)
 ---
+>>>            return _this;
 >>>        }
 1 >^^^^^^^^
 2 >        ^
 3 >         ^^^^^^^^^->
 1 > { 
 2 >        }
-1 >Emitted(28, 9) Source(2, 28) + SourceIndex(2)
-2 >Emitted(28, 10) Source(2, 29) + SourceIndex(2)
+1 >Emitted(29, 9) Source(2, 28) + SourceIndex(2)
+2 >Emitted(29, 10) Source(2, 29) + SourceIndex(2)
 ---
 >>>        return B;
 1->^^^^^^^^
 2 >        ^^^^^^^^
 1->
 2 >        }
-1->Emitted(29, 9) Source(2, 28) + SourceIndex(2)
-2 >Emitted(29, 17) Source(2, 29) + SourceIndex(2)
+1->Emitted(30, 9) Source(2, 28) + SourceIndex(2)
+2 >Emitted(30, 17) Source(2, 29) + SourceIndex(2)
 ---
 >>>    }(a_1.A));
 1 >^^^^
@@ -211,20 +212,20 @@ sourceFile:tests/cases/compiler/b.ts
 4 >     export class B extends 
 5 >      A
 6 >            { }
-1 >Emitted(30, 5) Source(2, 28) + SourceIndex(2)
-2 >Emitted(30, 6) Source(2, 29) + SourceIndex(2)
-3 >Emitted(30, 6) Source(2, 1) + SourceIndex(2)
-4 >Emitted(30, 7) Source(2, 24) + SourceIndex(2)
-5 >Emitted(30, 12) Source(2, 25) + SourceIndex(2)
-6 >Emitted(30, 15) Source(2, 29) + SourceIndex(2)
+1 >Emitted(31, 5) Source(2, 28) + SourceIndex(2)
+2 >Emitted(31, 6) Source(2, 29) + SourceIndex(2)
+3 >Emitted(31, 6) Source(2, 1) + SourceIndex(2)
+4 >Emitted(31, 7) Source(2, 24) + SourceIndex(2)
+5 >Emitted(31, 12) Source(2, 25) + SourceIndex(2)
+6 >Emitted(31, 15) Source(2, 29) + SourceIndex(2)
 ---
 >>>    exports.B = B;
 1->^^^^
 2 >    ^^^^^^^^^^^^^^
 1->
 2 >    export class B extends A { }
-1->Emitted(31, 5) Source(2, 1) + SourceIndex(2)
-2 >Emitted(31, 19) Source(2, 29) + SourceIndex(2)
+1->Emitted(32, 5) Source(2, 1) + SourceIndex(2)
+2 >Emitted(32, 19) Source(2, 29) + SourceIndex(2)
 ---
 >>>});
 >>>//# sourceMappingURL=all.js.map
\ No newline at end of file
diff --git a/tests/baselines/reference/overload1.js b/tests/baselines/reference/overload1.js
index fd05873c647..d83c8aea7ad 100644
--- a/tests/baselines/reference/overload1.js
+++ b/tests/baselines/reference/overload1.js
@@ -56,7 +56,8 @@ var O;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(A));
@@ -64,7 +65,8 @@ var O;
     var C = (function (_super) {
         __extends(C, _super);
         function C() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return C;
     }(B));
diff --git a/tests/baselines/reference/overloadOnConstConstraintChecks1.js b/tests/baselines/reference/overloadOnConstConstraintChecks1.js
index a3b7a329861..ad49f8e9d7a 100644
--- a/tests/baselines/reference/overloadOnConstConstraintChecks1.js
+++ b/tests/baselines/reference/overloadOnConstConstraintChecks1.js
@@ -37,7 +37,8 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived1.prototype.bar = function () { };
     return Derived1;
@@ -45,7 +46,8 @@ var Derived1 = (function (_super) {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived2.prototype.baz = function () { };
     return Derived2;
@@ -53,7 +55,8 @@ var Derived2 = (function (_super) {
 var Derived3 = (function (_super) {
     __extends(Derived3, _super);
     function Derived3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived3.prototype.biz = function () { };
     return Derived3;
diff --git a/tests/baselines/reference/overloadOnConstConstraintChecks2.js b/tests/baselines/reference/overloadOnConstConstraintChecks2.js
index efb57153b13..2b521b4baf5 100644
--- a/tests/baselines/reference/overloadOnConstConstraintChecks2.js
+++ b/tests/baselines/reference/overloadOnConstConstraintChecks2.js
@@ -25,14 +25,16 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     C.prototype.foo = function () { };
     return C;
diff --git a/tests/baselines/reference/overloadOnConstConstraintChecks3.js b/tests/baselines/reference/overloadOnConstConstraintChecks3.js
index 181f9d8129c..df5e0065adb 100644
--- a/tests/baselines/reference/overloadOnConstConstraintChecks3.js
+++ b/tests/baselines/reference/overloadOnConstConstraintChecks3.js
@@ -27,14 +27,16 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     C.prototype.foo = function () { };
     return C;
diff --git a/tests/baselines/reference/overloadOnConstConstraintChecks4.js b/tests/baselines/reference/overloadOnConstConstraintChecks4.js
index d73c59863ad..6a750612395 100644
--- a/tests/baselines/reference/overloadOnConstConstraintChecks4.js
+++ b/tests/baselines/reference/overloadOnConstConstraintChecks4.js
@@ -27,7 +27,8 @@ var Z = (function () {
 var A = (function (_super) {
     __extends(A, _super);
     function A() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.x = 1;
     }
     return A;
@@ -35,14 +36,16 @@ var A = (function (_super) {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     C.prototype.foo = function () { };
     return C;
diff --git a/tests/baselines/reference/overloadOnConstantsInvalidOverload1.js b/tests/baselines/reference/overloadOnConstantsInvalidOverload1.js
index c98075c04a1..5d0546d0edc 100644
--- a/tests/baselines/reference/overloadOnConstantsInvalidOverload1.js
+++ b/tests/baselines/reference/overloadOnConstantsInvalidOverload1.js
@@ -26,7 +26,8 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived1.prototype.bar = function () { };
     return Derived1;
@@ -34,7 +35,8 @@ var Derived1 = (function (_super) {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived2.prototype.baz = function () { };
     return Derived2;
@@ -42,7 +44,8 @@ var Derived2 = (function (_super) {
 var Derived3 = (function (_super) {
     __extends(Derived3, _super);
     function Derived3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived3.prototype.biz = function () { };
     return Derived3;
diff --git a/tests/baselines/reference/overloadResolution.js b/tests/baselines/reference/overloadResolution.js
index 0d25322fdfc..c34d037b350 100644
--- a/tests/baselines/reference/overloadResolution.js
+++ b/tests/baselines/reference/overloadResolution.js
@@ -108,21 +108,24 @@ var SomeBase = (function () {
 var SomeDerived1 = (function (_super) {
     __extends(SomeDerived1, _super);
     function SomeDerived1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return SomeDerived1;
 }(SomeBase));
 var SomeDerived2 = (function (_super) {
     __extends(SomeDerived2, _super);
     function SomeDerived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return SomeDerived2;
 }(SomeBase));
 var SomeDerived3 = (function (_super) {
     __extends(SomeDerived3, _super);
     function SomeDerived3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return SomeDerived3;
 }(SomeBase));
diff --git a/tests/baselines/reference/overloadResolutionClassConstructors.js b/tests/baselines/reference/overloadResolutionClassConstructors.js
index 9fa55fe1e95..0a899584c18 100644
--- a/tests/baselines/reference/overloadResolutionClassConstructors.js
+++ b/tests/baselines/reference/overloadResolutionClassConstructors.js
@@ -115,21 +115,24 @@ var SomeBase = (function () {
 var SomeDerived1 = (function (_super) {
     __extends(SomeDerived1, _super);
     function SomeDerived1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return SomeDerived1;
 }(SomeBase));
 var SomeDerived2 = (function (_super) {
     __extends(SomeDerived2, _super);
     function SomeDerived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return SomeDerived2;
 }(SomeBase));
 var SomeDerived3 = (function (_super) {
     __extends(SomeDerived3, _super);
     function SomeDerived3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return SomeDerived3;
 }(SomeBase));
diff --git a/tests/baselines/reference/overloadResolutionConstructors.js b/tests/baselines/reference/overloadResolutionConstructors.js
index 12d8480eefb..42dceff061e 100644
--- a/tests/baselines/reference/overloadResolutionConstructors.js
+++ b/tests/baselines/reference/overloadResolutionConstructors.js
@@ -116,21 +116,24 @@ var SomeBase = (function () {
 var SomeDerived1 = (function (_super) {
     __extends(SomeDerived1, _super);
     function SomeDerived1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return SomeDerived1;
 }(SomeBase));
 var SomeDerived2 = (function (_super) {
     __extends(SomeDerived2, _super);
     function SomeDerived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return SomeDerived2;
 }(SomeBase));
 var SomeDerived3 = (function (_super) {
     __extends(SomeDerived3, _super);
     function SomeDerived3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return SomeDerived3;
 }(SomeBase));
diff --git a/tests/baselines/reference/overloadingOnConstants1.js b/tests/baselines/reference/overloadingOnConstants1.js
index b261201be40..52d8a1b7abe 100644
--- a/tests/baselines/reference/overloadingOnConstants1.js
+++ b/tests/baselines/reference/overloadingOnConstants1.js
@@ -40,7 +40,8 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived1.prototype.bar = function () { };
     return Derived1;
@@ -48,7 +49,8 @@ var Derived1 = (function (_super) {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived2.prototype.baz = function () { };
     return Derived2;
@@ -56,7 +58,8 @@ var Derived2 = (function (_super) {
 var Derived3 = (function (_super) {
     __extends(Derived3, _super);
     function Derived3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived3.prototype.biz = function () { };
     return Derived3;
diff --git a/tests/baselines/reference/overloadingOnConstants2.js b/tests/baselines/reference/overloadingOnConstants2.js
index 977ae7ec5b9..85976ae7fcd 100644
--- a/tests/baselines/reference/overloadingOnConstants2.js
+++ b/tests/baselines/reference/overloadingOnConstants2.js
@@ -42,7 +42,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/overridingPrivateStaticMembers.js b/tests/baselines/reference/overridingPrivateStaticMembers.js
index ddd9fae6429..b7ad5b66554 100644
--- a/tests/baselines/reference/overridingPrivateStaticMembers.js
+++ b/tests/baselines/reference/overridingPrivateStaticMembers.js
@@ -21,7 +21,8 @@ var Base2 = (function () {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Base2));
diff --git a/tests/baselines/reference/parseErrorInHeritageClause1.js b/tests/baselines/reference/parseErrorInHeritageClause1.js
index e2f66bfadd7..0a29bdf2da0 100644
--- a/tests/baselines/reference/parseErrorInHeritageClause1.js
+++ b/tests/baselines/reference/parseErrorInHeritageClause1.js
@@ -11,7 +11,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/parser509630.js b/tests/baselines/reference/parser509630.js
index 4d94ea619ec..cdef63aa80f 100644
--- a/tests/baselines/reference/parser509630.js
+++ b/tests/baselines/reference/parser509630.js
@@ -21,7 +21,8 @@ var Type = (function () {
 var Any = (function (_super) {
     __extends(Any, _super);
     function Any() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Any;
 }(Type));
diff --git a/tests/baselines/reference/parserAstSpans1.js b/tests/baselines/reference/parserAstSpans1.js
index 41f07380e97..6e6a423fe90 100644
--- a/tests/baselines/reference/parserAstSpans1.js
+++ b/tests/baselines/reference/parserAstSpans1.js
@@ -318,7 +318,8 @@ var c2 = (function () {
 var c3 = (function (_super) {
     __extends(c3, _super);
     function c3() {
-        _super.call(this, 10);
+        var _this;
+        _this = _super.call(this, 10) || this;
         this.p1 = _super.prototype.c2_p1;
     }
     /** c3 f1*/
@@ -362,7 +363,8 @@ c2_i.nc_f1();
 var c4 = (function (_super) {
     __extends(c4, _super);
     function c4() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return c4;
 }(c2));
@@ -404,7 +406,8 @@ var c5 = (function () {
 var c6 = (function (_super) {
     __extends(c6, _super);
     function c6() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         this.d = _super.prototype.b;
     }
     return c6;
diff --git a/tests/baselines/reference/parserClassDeclaration1.js b/tests/baselines/reference/parserClassDeclaration1.js
index 41ecc9135c0..f91efad621e 100644
--- a/tests/baselines/reference/parserClassDeclaration1.js
+++ b/tests/baselines/reference/parserClassDeclaration1.js
@@ -11,7 +11,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/parserClassDeclaration3.js b/tests/baselines/reference/parserClassDeclaration3.js
index c375b4b5a21..9d51b0ed25e 100644
--- a/tests/baselines/reference/parserClassDeclaration3.js
+++ b/tests/baselines/reference/parserClassDeclaration3.js
@@ -11,7 +11,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(B));
diff --git a/tests/baselines/reference/parserClassDeclaration4.js b/tests/baselines/reference/parserClassDeclaration4.js
index f19ac06c35c..7c91281d05c 100644
--- a/tests/baselines/reference/parserClassDeclaration4.js
+++ b/tests/baselines/reference/parserClassDeclaration4.js
@@ -11,7 +11,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/parserClassDeclaration5.js b/tests/baselines/reference/parserClassDeclaration5.js
index 272edc89fb6..aeb7ce09190 100644
--- a/tests/baselines/reference/parserClassDeclaration5.js
+++ b/tests/baselines/reference/parserClassDeclaration5.js
@@ -11,7 +11,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/parserClassDeclaration6.js b/tests/baselines/reference/parserClassDeclaration6.js
index 88d8481d52a..b14257310c4 100644
--- a/tests/baselines/reference/parserClassDeclaration6.js
+++ b/tests/baselines/reference/parserClassDeclaration6.js
@@ -11,7 +11,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/parserErrorRecovery_ExtendsOrImplementsClause2.js b/tests/baselines/reference/parserErrorRecovery_ExtendsOrImplementsClause2.js
index b53c41fb45c..c4a2fd29711 100644
--- a/tests/baselines/reference/parserErrorRecovery_ExtendsOrImplementsClause2.js
+++ b/tests/baselines/reference/parserErrorRecovery_ExtendsOrImplementsClause2.js
@@ -11,7 +11,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/parserErrorRecovery_ExtendsOrImplementsClause4.js b/tests/baselines/reference/parserErrorRecovery_ExtendsOrImplementsClause4.js
index 500f6d38c6d..ae9d5068e29 100644
--- a/tests/baselines/reference/parserErrorRecovery_ExtendsOrImplementsClause4.js
+++ b/tests/baselines/reference/parserErrorRecovery_ExtendsOrImplementsClause4.js
@@ -11,7 +11,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/parserErrorRecovery_ExtendsOrImplementsClause5.js b/tests/baselines/reference/parserErrorRecovery_ExtendsOrImplementsClause5.js
index 8c02a996ea5..8992706cd16 100644
--- a/tests/baselines/reference/parserErrorRecovery_ExtendsOrImplementsClause5.js
+++ b/tests/baselines/reference/parserErrorRecovery_ExtendsOrImplementsClause5.js
@@ -11,7 +11,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/parserGenericsInTypeContexts1.js b/tests/baselines/reference/parserGenericsInTypeContexts1.js
index f6f4f39393f..0ec560c1306 100644
--- a/tests/baselines/reference/parserGenericsInTypeContexts1.js
+++ b/tests/baselines/reference/parserGenericsInTypeContexts1.js
@@ -26,7 +26,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/parserGenericsInTypeContexts2.js b/tests/baselines/reference/parserGenericsInTypeContexts2.js
index 99e19586c52..d4c754fb0b1 100644
--- a/tests/baselines/reference/parserGenericsInTypeContexts2.js
+++ b/tests/baselines/reference/parserGenericsInTypeContexts2.js
@@ -26,7 +26,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/parserRealSource10.js b/tests/baselines/reference/parserRealSource10.js
index 255cad3ca21..429a388c894 100644
--- a/tests/baselines/reference/parserRealSource10.js
+++ b/tests/baselines/reference/parserRealSource10.js
@@ -826,7 +826,8 @@ var TypeScript;
     var NumberLiteralToken = (function (_super) {
         __extends(NumberLiteralToken, _super);
         function NumberLiteralToken(value, hasEmptyFraction) {
-            _super.call(this, TokenID.NumberLiteral);
+            var _this;
+            _this = _super.call(this, TokenID.NumberLiteral) || this;
             this.value = value;
             this.hasEmptyFraction = hasEmptyFraction;
         }
@@ -842,7 +843,8 @@ var TypeScript;
     var StringLiteralToken = (function (_super) {
         __extends(StringLiteralToken, _super);
         function StringLiteralToken(value) {
-            _super.call(this, TokenID.StringLiteral);
+            var _this;
+            _this = _super.call(this, TokenID.StringLiteral) || this;
             this.value = value;
         }
         StringLiteralToken.prototype.getText = function () {
@@ -857,7 +859,8 @@ var TypeScript;
     var IdentifierToken = (function (_super) {
         __extends(IdentifierToken, _super);
         function IdentifierToken(value, hasEscapeSequence) {
-            _super.call(this, TokenID.Identifier);
+            var _this;
+            _this = _super.call(this, TokenID.Identifier) || this;
             this.value = value;
             this.hasEscapeSequence = hasEscapeSequence;
         }
@@ -873,7 +876,8 @@ var TypeScript;
     var WhitespaceToken = (function (_super) {
         __extends(WhitespaceToken, _super);
         function WhitespaceToken(tokenId, value) {
-            _super.call(this, tokenId);
+            var _this;
+            _this = _super.call(this, tokenId) || this;
             this.value = value;
         }
         WhitespaceToken.prototype.getText = function () {
@@ -888,7 +892,8 @@ var TypeScript;
     var CommentToken = (function (_super) {
         __extends(CommentToken, _super);
         function CommentToken(tokenID, value, isBlock, startPos, line, endsLine) {
-            _super.call(this, tokenID);
+            var _this;
+            _this = _super.call(this, tokenID) || this;
             this.value = value;
             this.isBlock = isBlock;
             this.startPos = startPos;
@@ -907,7 +912,8 @@ var TypeScript;
     var RegularExpressionLiteralToken = (function (_super) {
         __extends(RegularExpressionLiteralToken, _super);
         function RegularExpressionLiteralToken(regex) {
-            _super.call(this, TokenID.RegularExpressionLiteral);
+            var _this;
+            _this = _super.call(this, TokenID.RegularExpressionLiteral) || this;
             this.regex = regex;
         }
         RegularExpressionLiteralToken.prototype.getText = function () {
diff --git a/tests/baselines/reference/parserRealSource11.js b/tests/baselines/reference/parserRealSource11.js
index 0c1d1064255..4be1ed20767 100644
--- a/tests/baselines/reference/parserRealSource11.js
+++ b/tests/baselines/reference/parserRealSource11.js
@@ -2386,7 +2386,8 @@ var TypeScript;
     var AST = (function (_super) {
         __extends(AST, _super);
         function AST(nodeType) {
-            _super.call(this);
+            var _this;
+            _this = _super.call(this) || this;
             this.nodeType = nodeType;
             this.type = null;
             this.flags = ASTFlags.Writeable;
@@ -2542,7 +2543,8 @@ var TypeScript;
     var IncompleteAST = (function (_super) {
         __extends(IncompleteAST, _super);
         function IncompleteAST(min, lim) {
-            _super.call(this, NodeType.Error);
+            var _this;
+            _this = _super.call(this, NodeType.Error) || this;
             this.minChar = min;
             this.limChar = lim;
         }
@@ -2552,7 +2554,8 @@ var TypeScript;
     var ASTList = (function (_super) {
         __extends(ASTList, _super);
         function ASTList() {
-            _super.call(this, NodeType.List);
+            var _this;
+            _this = _super.call(this, NodeType.List) || this;
             this.enclosingScope = null;
             this.members = new AST[];
         }
@@ -2619,7 +2622,8 @@ var TypeScript;
         //    To change text, and to avoid running into a situation where 'actualText' does not 
         //    match 'text', always use setText.
         function Identifier(actualText, hasEscapeSequence) {
-            _super.call(this, NodeType.Name);
+            var _this;
+            _this = _super.call(this, NodeType.Name) || this;
             this.actualText = actualText;
             this.hasEscapeSequence = hasEscapeSequence;
             this.sym = null;
@@ -2663,7 +2667,8 @@ var TypeScript;
     var MissingIdentifier = (function (_super) {
         __extends(MissingIdentifier, _super);
         function MissingIdentifier() {
-            _super.call(this, "__missing");
+            var _this;
+            _this = _super.call(this, "__missing") || this;
         }
         MissingIdentifier.prototype.isMissing = function () {
             return true;
@@ -2677,7 +2682,8 @@ var TypeScript;
     var Label = (function (_super) {
         __extends(Label, _super);
         function Label(id) {
-            _super.call(this, NodeType.Label);
+            var _this;
+            _this = _super.call(this, NodeType.Label) || this;
             this.id = id;
         }
         Label.prototype.printLabel = function () { return this.id.actualText + ":"; };
@@ -2701,7 +2707,8 @@ var TypeScript;
     var Expression = (function (_super) {
         __extends(Expression, _super);
         function Expression(nodeType) {
-            _super.call(this, nodeType);
+            var _this;
+            _this = _super.call(this, nodeType) || this;
         }
         Expression.prototype.isExpression = function () { return true; };
         Expression.prototype.isStatementOrExpression = function () { return true; };
@@ -2711,7 +2718,8 @@ var TypeScript;
     var UnaryExpression = (function (_super) {
         __extends(UnaryExpression, _super);
         function UnaryExpression(nodeType, operand) {
-            _super.call(this, nodeType);
+            var _this;
+            _this = _super.call(this, nodeType) || this;
             this.operand = operand;
             this.targetType = null; // Target type for an object literal (null if no target type)
             this.castTerm = null;
@@ -2855,7 +2863,8 @@ var TypeScript;
     var CallExpression = (function (_super) {
         __extends(CallExpression, _super);
         function CallExpression(nodeType, target, arguments) {
-            _super.call(this, nodeType);
+            var _this;
+            _this = _super.call(this, nodeType) || this;
             this.target = target;
             this.arguments = arguments;
             this.signature = null;
@@ -2887,7 +2896,8 @@ var TypeScript;
     var BinaryExpression = (function (_super) {
         __extends(BinaryExpression, _super);
         function BinaryExpression(nodeType, operand1, operand2) {
-            _super.call(this, nodeType);
+            var _this;
+            _this = _super.call(this, nodeType) || this;
             this.operand1 = operand1;
             this.operand2 = operand2;
         }
@@ -3039,7 +3049,8 @@ var TypeScript;
     var ConditionalExpression = (function (_super) {
         __extends(ConditionalExpression, _super);
         function ConditionalExpression(operand1, operand2, operand3) {
-            _super.call(this, NodeType.ConditionalExpression);
+            var _this;
+            _this = _super.call(this, NodeType.ConditionalExpression) || this;
             this.operand1 = operand1;
             this.operand2 = operand2;
             this.operand3 = operand3;
@@ -3064,7 +3075,8 @@ var TypeScript;
     var NumberLiteral = (function (_super) {
         __extends(NumberLiteral, _super);
         function NumberLiteral(value, hasEmptyFraction) {
-            _super.call(this, NodeType.NumberLit);
+            var _this;
+            _this = _super.call(this, NodeType.NumberLit) || this;
             this.value = value;
             this.hasEmptyFraction = hasEmptyFraction;
             this.isNegativeZero = false;
@@ -3105,7 +3117,8 @@ var TypeScript;
     var RegexLiteral = (function (_super) {
         __extends(RegexLiteral, _super);
         function RegexLiteral(regex) {
-            _super.call(this, NodeType.Regex);
+            var _this;
+            _this = _super.call(this, NodeType.Regex) || this;
             this.regex = regex;
         }
         RegexLiteral.prototype.typeCheck = function (typeFlow) {
@@ -3125,7 +3138,8 @@ var TypeScript;
     var StringLiteral = (function (_super) {
         __extends(StringLiteral, _super);
         function StringLiteral(text) {
-            _super.call(this, NodeType.QString);
+            var _this;
+            _this = _super.call(this, NodeType.QString) || this;
             this.text = text;
         }
         StringLiteral.prototype.emit = function (emitter, tokenId, startLine) {
@@ -3151,7 +3165,8 @@ var TypeScript;
     var ModuleElement = (function (_super) {
         __extends(ModuleElement, _super);
         function ModuleElement(nodeType) {
-            _super.call(this, nodeType);
+            var _this;
+            _this = _super.call(this, nodeType) || this;
         }
         return ModuleElement;
     }(AST));
@@ -3159,7 +3174,8 @@ var TypeScript;
     var ImportDeclaration = (function (_super) {
         __extends(ImportDeclaration, _super);
         function ImportDeclaration(id, alias) {
-            _super.call(this, NodeType.ImportDeclaration);
+            var _this;
+            _this = _super.call(this, NodeType.ImportDeclaration) || this;
             this.id = id;
             this.alias = alias;
             this.varFlags = VarFlags.None;
@@ -3218,7 +3234,8 @@ var TypeScript;
     var BoundDecl = (function (_super) {
         __extends(BoundDecl, _super);
         function BoundDecl(id, nodeType, nestingLevel) {
-            _super.call(this, nodeType);
+            var _this;
+            _this = _super.call(this, nodeType) || this;
             this.id = id;
             this.nestingLevel = nestingLevel;
             this.init = null;
@@ -3242,7 +3259,8 @@ var TypeScript;
     var VarDecl = (function (_super) {
         __extends(VarDecl, _super);
         function VarDecl(id, nest) {
-            _super.call(this, id, NodeType.VarDecl, nest);
+            var _this;
+            _this = _super.call(this, id, NodeType.VarDecl, nest) || this;
         }
         VarDecl.prototype.isAmbient = function () { return hasFlag(this.varFlags, VarFlags.Ambient); };
         VarDecl.prototype.isExported = function () { return hasFlag(this.varFlags, VarFlags.Exported); };
@@ -3259,7 +3277,8 @@ var TypeScript;
     var ArgDecl = (function (_super) {
         __extends(ArgDecl, _super);
         function ArgDecl(id) {
-            _super.call(this, id, NodeType.ArgDecl, 0);
+            var _this;
+            _this = _super.call(this, id, NodeType.ArgDecl, 0) || this;
             this.isOptional = false;
             this.parameterPropertySym = null;
         }
@@ -3281,7 +3300,8 @@ var TypeScript;
     var FuncDecl = (function (_super) {
         __extends(FuncDecl, _super);
         function FuncDecl(name, bod, isConstructor, arguments, vars, scopes, statics, nodeType) {
-            _super.call(this, nodeType);
+            var _this;
+            _this = _super.call(this, nodeType) || this;
             this.name = name;
             this.bod = bod;
             this.isConstructor = isConstructor;
@@ -3421,7 +3441,8 @@ var TypeScript;
     var Script = (function (_super) {
         __extends(Script, _super);
         function Script(vars, scopes) {
-            _super.call(this, new Identifier("script"), null, false, null, vars, scopes, null, NodeType.Script);
+            var _this;
+            _this = _super.call(this, new Identifier("script"), null, false, null, vars, scopes, null, NodeType.Script) || this;
             this.locationInfo = null;
             this.referencedFiles = [];
             this.requiresGlobal = false;
@@ -3490,7 +3511,8 @@ var TypeScript;
     var NamedDeclaration = (function (_super) {
         __extends(NamedDeclaration, _super);
         function NamedDeclaration(nodeType, name, members) {
-            _super.call(this, nodeType);
+            var _this;
+            _this = _super.call(this, nodeType) || this;
             this.name = name;
             this.members = members;
             this.leftCurlyCount = 0;
@@ -3502,7 +3524,8 @@ var TypeScript;
     var ModuleDeclaration = (function (_super) {
         __extends(ModuleDeclaration, _super);
         function ModuleDeclaration(name, members, vars, scopes, endingToken) {
-            _super.call(this, NodeType.ModuleDeclaration, name, members);
+            var _this;
+            _this = _super.call(this, NodeType.ModuleDeclaration, name, members) || this;
             this.endingToken = endingToken;
             this.modFlags = ModuleFlags.ShouldEmitModuleDecl;
             this.amdDependencies = [];
@@ -3537,7 +3560,8 @@ var TypeScript;
     var TypeDeclaration = (function (_super) {
         __extends(TypeDeclaration, _super);
         function TypeDeclaration(nodeType, name, extendsList, implementsList, members) {
-            _super.call(this, nodeType, name, members);
+            var _this;
+            _this = _super.call(this, nodeType, name, members) || this;
             this.extendsList = extendsList;
             this.implementsList = implementsList;
             this.varFlags = VarFlags.None;
@@ -3554,7 +3578,8 @@ var TypeScript;
     var ClassDeclaration = (function (_super) {
         __extends(ClassDeclaration, _super);
         function ClassDeclaration(name, members, extendsList, implementsList) {
-            _super.call(this, NodeType.ClassDeclaration, name, extendsList, implementsList, members);
+            var _this;
+            _this = _super.call(this, NodeType.ClassDeclaration, name, extendsList, implementsList, members) || this;
             this.knownMemberNames = {};
             this.constructorDecl = null;
             this.constructorNestingLevel = 0;
@@ -3572,7 +3597,8 @@ var TypeScript;
     var InterfaceDeclaration = (function (_super) {
         __extends(InterfaceDeclaration, _super);
         function InterfaceDeclaration(name, members, extendsList, implementsList) {
-            _super.call(this, NodeType.InterfaceDeclaration, name, extendsList, implementsList, members);
+            var _this;
+            _this = _super.call(this, NodeType.InterfaceDeclaration, name, extendsList, implementsList, members) || this;
         }
         InterfaceDeclaration.prototype.typeCheck = function (typeFlow) {
             return typeFlow.typeCheckInterface(this);
@@ -3585,7 +3611,8 @@ var TypeScript;
     var Statement = (function (_super) {
         __extends(Statement, _super);
         function Statement(nodeType) {
-            _super.call(this, nodeType);
+            var _this;
+            _this = _super.call(this, nodeType) || this;
             this.flags |= ASTFlags.IsStatement;
         }
         Statement.prototype.isLoop = function () { return false; };
@@ -3601,7 +3628,8 @@ var TypeScript;
     var LabeledStatement = (function (_super) {
         __extends(LabeledStatement, _super);
         function LabeledStatement(labels, stmt) {
-            _super.call(this, NodeType.LabeledStatement);
+            var _this;
+            _this = _super.call(this, NodeType.LabeledStatement) || this;
             this.labels = labels;
             this.stmt = stmt;
         }
@@ -3635,7 +3663,8 @@ var TypeScript;
     var Block = (function (_super) {
         __extends(Block, _super);
         function Block(statements, isStatementBlock) {
-            _super.call(this, NodeType.Block);
+            var _this;
+            _this = _super.call(this, NodeType.Block) || this;
             this.statements = statements;
             this.isStatementBlock = isStatementBlock;
         }
@@ -3690,7 +3719,8 @@ var TypeScript;
     var Jump = (function (_super) {
         __extends(Jump, _super);
         function Jump(nodeType) {
-            _super.call(this, nodeType);
+            var _this;
+            _this = _super.call(this, nodeType) || this;
             this.target = null;
             this.resolvedTarget = null;
         }
@@ -3741,7 +3771,8 @@ var TypeScript;
     var WhileStatement = (function (_super) {
         __extends(WhileStatement, _super);
         function WhileStatement(cond) {
-            _super.call(this, NodeType.While);
+            var _this;
+            _this = _super.call(this, NodeType.While) || this;
             this.cond = cond;
             this.body = null;
         }
@@ -3793,7 +3824,8 @@ var TypeScript;
     var DoWhileStatement = (function (_super) {
         __extends(DoWhileStatement, _super);
         function DoWhileStatement() {
-            _super.call(this, NodeType.DoWhile);
+            var _this;
+            _this = _super.call(this, NodeType.DoWhile) || this;
             this.body = null;
             this.whileAST = null;
             this.cond = null;
@@ -3849,7 +3881,8 @@ var TypeScript;
     var IfStatement = (function (_super) {
         __extends(IfStatement, _super);
         function IfStatement(cond) {
-            _super.call(this, NodeType.If);
+            var _this;
+            _this = _super.call(this, NodeType.If) || this;
             this.cond = cond;
             this.elseBod = null;
             this.statement = new ASTSpan();
@@ -3927,7 +3960,8 @@ var TypeScript;
     var ReturnStatement = (function (_super) {
         __extends(ReturnStatement, _super);
         function ReturnStatement() {
-            _super.call(this, NodeType.Return);
+            var _this;
+            _this = _super.call(this, NodeType.Return) || this;
             this.returnExpression = null;
         }
         ReturnStatement.prototype.emit = function (emitter, tokenId, startLine) {
@@ -3958,7 +3992,8 @@ var TypeScript;
     var EndCode = (function (_super) {
         __extends(EndCode, _super);
         function EndCode() {
-            _super.call(this, NodeType.EndCode);
+            var _this;
+            _this = _super.call(this, NodeType.EndCode) || this;
         }
         return EndCode;
     }(AST));
@@ -3966,7 +4001,8 @@ var TypeScript;
     var ForInStatement = (function (_super) {
         __extends(ForInStatement, _super);
         function ForInStatement(lval, obj) {
-            _super.call(this, NodeType.ForIn);
+            var _this;
+            _this = _super.call(this, NodeType.ForIn) || this;
             this.lval = lval;
             this.obj = obj;
             this.statement = new ASTSpan();
@@ -4081,7 +4117,8 @@ var TypeScript;
     var ForStatement = (function (_super) {
         __extends(ForStatement, _super);
         function ForStatement(init) {
-            _super.call(this, NodeType.For);
+            var _this;
+            _this = _super.call(this, NodeType.For) || this;
             this.init = init;
         }
         ForStatement.prototype.isLoop = function () { return true; };
@@ -4172,7 +4209,8 @@ var TypeScript;
     var WithStatement = (function (_super) {
         __extends(WithStatement, _super);
         function WithStatement(expr) {
-            _super.call(this, NodeType.With);
+            var _this;
+            _this = _super.call(this, NodeType.With) || this;
             this.expr = expr;
             this.withSym = null;
         }
@@ -4198,7 +4236,8 @@ var TypeScript;
     var SwitchStatement = (function (_super) {
         __extends(SwitchStatement, _super);
         function SwitchStatement(val) {
-            _super.call(this, NodeType.Switch);
+            var _this;
+            _this = _super.call(this, NodeType.Switch) || this;
             this.val = val;
             this.defaultCase = null;
             this.statement = new ASTSpan();
@@ -4270,7 +4309,8 @@ var TypeScript;
     var CaseStatement = (function (_super) {
         __extends(CaseStatement, _super);
         function CaseStatement() {
-            _super.call(this, NodeType.Case);
+            var _this;
+            _this = _super.call(this, NodeType.Case) || this;
             this.expr = null;
         }
         CaseStatement.prototype.emit = function (emitter, tokenId, startLine) {
@@ -4323,7 +4363,8 @@ var TypeScript;
     var TypeReference = (function (_super) {
         __extends(TypeReference, _super);
         function TypeReference(term, arrayCount) {
-            _super.call(this, NodeType.TypeRef);
+            var _this;
+            _this = _super.call(this, NodeType.TypeRef) || this;
             this.term = term;
             this.arrayCount = arrayCount;
         }
@@ -4353,7 +4394,8 @@ var TypeScript;
     var TryFinally = (function (_super) {
         __extends(TryFinally, _super);
         function TryFinally(tryNode, finallyNode) {
-            _super.call(this, NodeType.TryFinally);
+            var _this;
+            _this = _super.call(this, NodeType.TryFinally) || this;
             this.tryNode = tryNode;
             this.finallyNode = finallyNode;
         }
@@ -4398,7 +4440,8 @@ var TypeScript;
     var TryCatch = (function (_super) {
         __extends(TryCatch, _super);
         function TryCatch(tryNode, catchNode) {
-            _super.call(this, NodeType.TryCatch);
+            var _this;
+            _this = _super.call(this, NodeType.TryCatch) || this;
             this.tryNode = tryNode;
             this.catchNode = catchNode;
         }
@@ -4448,7 +4491,8 @@ var TypeScript;
     var Try = (function (_super) {
         __extends(Try, _super);
         function Try(body) {
-            _super.call(this, NodeType.Try);
+            var _this;
+            _this = _super.call(this, NodeType.Try) || this;
             this.body = body;
         }
         Try.prototype.emit = function (emitter, tokenId, startLine) {
@@ -4476,7 +4520,8 @@ var TypeScript;
     var Catch = (function (_super) {
         __extends(Catch, _super);
         function Catch(param, body) {
-            _super.call(this, NodeType.Catch);
+            var _this;
+            _this = _super.call(this, NodeType.Catch) || this;
             this.param = param;
             this.body = body;
             this.statement = new ASTSpan();
@@ -4549,7 +4594,8 @@ var TypeScript;
     var Finally = (function (_super) {
         __extends(Finally, _super);
         function Finally(body) {
-            _super.call(this, NodeType.Finally);
+            var _this;
+            _this = _super.call(this, NodeType.Finally) || this;
             this.body = body;
         }
         Finally.prototype.emit = function (emitter, tokenId, startLine) {
@@ -4577,7 +4623,8 @@ var TypeScript;
     var Comment = (function (_super) {
         __extends(Comment, _super);
         function Comment(content, isBlockComment, endsLine) {
-            _super.call(this, NodeType.Comment);
+            var _this;
+            _this = _super.call(this, NodeType.Comment) || this;
             this.content = content;
             this.isBlockComment = isBlockComment;
             this.endsLine = endsLine;
@@ -4603,7 +4650,8 @@ var TypeScript;
     var DebuggerStatement = (function (_super) {
         __extends(DebuggerStatement, _super);
         function DebuggerStatement() {
-            _super.call(this, NodeType.Debugger);
+            var _this;
+            _this = _super.call(this, NodeType.Debugger) || this;
         }
         DebuggerStatement.prototype.emit = function (emitter, tokenId, startLine) {
             emitter.emitParensAndCommentsInPlace(this, true);
diff --git a/tests/baselines/reference/parserharness.js b/tests/baselines/reference/parserharness.js
index 1a525c49d19..3f7e05e7164 100644
--- a/tests/baselines/reference/parserharness.js
+++ b/tests/baselines/reference/parserharness.js
@@ -2380,7 +2380,8 @@ var Harness;
     var TestCase = (function (_super) {
         __extends(TestCase, _super);
         function TestCase(description, block) {
-            _super.call(this, description, block);
+            var _this;
+            _this = _super.call(this, description, block) || this;
             this.description = description;
             this.block = block;
         }
@@ -2414,7 +2415,8 @@ var Harness;
     var Scenario = (function (_super) {
         __extends(Scenario, _super);
         function Scenario(description, block) {
-            _super.call(this, description, block);
+            var _this;
+            _this = _super.call(this, description, block) || this;
             this.description = description;
             this.block = block;
         }
@@ -2469,7 +2471,8 @@ var Harness;
     var Run = (function (_super) {
         __extends(Run, _super);
         function Run() {
-            _super.call(this, 'Test Run', null);
+            var _this;
+            _this = _super.call(this, 'Test Run', null) || this;
         }
         Run.prototype.run = function () {
             emitLog('start');
diff --git a/tests/baselines/reference/primitiveMembers.js b/tests/baselines/reference/primitiveMembers.js
index caf41fe2708..5425696b133 100644
--- a/tests/baselines/reference/primitiveMembers.js
+++ b/tests/baselines/reference/primitiveMembers.js
@@ -63,7 +63,8 @@ var baz = (function () {
 var foo = (function (_super) {
     __extends(foo, _super);
     function foo() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     foo.prototype.bar = function () { return undefined; };
     ;
diff --git a/tests/baselines/reference/privacyClass.js b/tests/baselines/reference/privacyClass.js
index a149aa26f75..8181d0612a8 100644
--- a/tests/baselines/reference/privacyClass.js
+++ b/tests/baselines/reference/privacyClass.js
@@ -152,21 +152,24 @@ var m1;
     var m1_C1_private = (function (_super) {
         __extends(m1_C1_private, _super);
         function m1_C1_private() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return m1_C1_private;
     }(m1_c_public));
     var m1_C2_private = (function (_super) {
         __extends(m1_C2_private, _super);
         function m1_C2_private() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return m1_C2_private;
     }(m1_c_private));
     var m1_C3_public = (function (_super) {
         __extends(m1_C3_public, _super);
         function m1_C3_public() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return m1_C3_public;
     }(m1_c_public));
@@ -174,7 +177,8 @@ var m1;
     var m1_C4_public = (function (_super) {
         __extends(m1_C4_public, _super);
         function m1_C4_public() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return m1_C4_public;
     }(m1_c_private));
@@ -204,21 +208,24 @@ var m1;
     var m1_C9_private = (function (_super) {
         __extends(m1_C9_private, _super);
         function m1_C9_private() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return m1_C9_private;
     }(m1_c_public));
     var m1_C10_private = (function (_super) {
         __extends(m1_C10_private, _super);
         function m1_C10_private() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return m1_C10_private;
     }(m1_c_private));
     var m1_C11_public = (function (_super) {
         __extends(m1_C11_public, _super);
         function m1_C11_public() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return m1_C11_public;
     }(m1_c_public));
@@ -226,7 +233,8 @@ var m1;
     var m1_C12_public = (function (_super) {
         __extends(m1_C12_public, _super);
         function m1_C12_public() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return m1_C12_public;
     }(m1_c_private));
@@ -250,21 +258,24 @@ var m2;
     var m2_C1_private = (function (_super) {
         __extends(m2_C1_private, _super);
         function m2_C1_private() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return m2_C1_private;
     }(m2_c_public));
     var m2_C2_private = (function (_super) {
         __extends(m2_C2_private, _super);
         function m2_C2_private() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return m2_C2_private;
     }(m2_c_private));
     var m2_C3_public = (function (_super) {
         __extends(m2_C3_public, _super);
         function m2_C3_public() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return m2_C3_public;
     }(m2_c_public));
@@ -272,7 +283,8 @@ var m2;
     var m2_C4_public = (function (_super) {
         __extends(m2_C4_public, _super);
         function m2_C4_public() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return m2_C4_public;
     }(m2_c_private));
@@ -302,21 +314,24 @@ var m2;
     var m2_C9_private = (function (_super) {
         __extends(m2_C9_private, _super);
         function m2_C9_private() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return m2_C9_private;
     }(m2_c_public));
     var m2_C10_private = (function (_super) {
         __extends(m2_C10_private, _super);
         function m2_C10_private() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return m2_C10_private;
     }(m2_c_private));
     var m2_C11_public = (function (_super) {
         __extends(m2_C11_public, _super);
         function m2_C11_public() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return m2_C11_public;
     }(m2_c_public));
@@ -324,7 +339,8 @@ var m2;
     var m2_C12_public = (function (_super) {
         __extends(m2_C12_public, _super);
         function m2_C12_public() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return m2_C12_public;
     }(m2_c_private));
@@ -346,21 +362,24 @@ var glo_c_private = (function () {
 var glo_C1_private = (function (_super) {
     __extends(glo_C1_private, _super);
     function glo_C1_private() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return glo_C1_private;
 }(glo_c_public));
 var glo_C2_private = (function (_super) {
     __extends(glo_C2_private, _super);
     function glo_C2_private() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return glo_C2_private;
 }(glo_c_private));
 var glo_C3_public = (function (_super) {
     __extends(glo_C3_public, _super);
     function glo_C3_public() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return glo_C3_public;
 }(glo_c_public));
@@ -368,7 +387,8 @@ exports.glo_C3_public = glo_C3_public;
 var glo_C4_public = (function (_super) {
     __extends(glo_C4_public, _super);
     function glo_C4_public() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return glo_C4_public;
 }(glo_c_private));
@@ -398,21 +418,24 @@ exports.glo_C8_public = glo_C8_public;
 var glo_C9_private = (function (_super) {
     __extends(glo_C9_private, _super);
     function glo_C9_private() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return glo_C9_private;
 }(glo_c_public));
 var glo_C10_private = (function (_super) {
     __extends(glo_C10_private, _super);
     function glo_C10_private() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return glo_C10_private;
 }(glo_c_private));
 var glo_C11_public = (function (_super) {
     __extends(glo_C11_public, _super);
     function glo_C11_public() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return glo_C11_public;
 }(glo_c_public));
@@ -420,7 +443,8 @@ exports.glo_C11_public = glo_C11_public;
 var glo_C12_public = (function (_super) {
     __extends(glo_C12_public, _super);
     function glo_C12_public() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return glo_C12_public;
 }(glo_c_private));
diff --git a/tests/baselines/reference/privacyClassExtendsClauseDeclFile.js b/tests/baselines/reference/privacyClassExtendsClauseDeclFile.js
index e2bb58781de..fe3ae6ba6d0 100644
--- a/tests/baselines/reference/privacyClassExtendsClauseDeclFile.js
+++ b/tests/baselines/reference/privacyClassExtendsClauseDeclFile.js
@@ -122,21 +122,24 @@ var publicModule;
     var privateClassExtendingPublicClassInModule = (function (_super) {
         __extends(privateClassExtendingPublicClassInModule, _super);
         function privateClassExtendingPublicClassInModule() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return privateClassExtendingPublicClassInModule;
     }(publicClassInPublicModule));
     var privateClassExtendingPrivateClassInModule = (function (_super) {
         __extends(privateClassExtendingPrivateClassInModule, _super);
         function privateClassExtendingPrivateClassInModule() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return privateClassExtendingPrivateClassInModule;
     }(privateClassInPublicModule));
     var publicClassExtendingPublicClassInModule = (function (_super) {
         __extends(publicClassExtendingPublicClassInModule, _super);
         function publicClassExtendingPublicClassInModule() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return publicClassExtendingPublicClassInModule;
     }(publicClassInPublicModule));
@@ -144,7 +147,8 @@ var publicModule;
     var publicClassExtendingPrivateClassInModule = (function (_super) {
         __extends(publicClassExtendingPrivateClassInModule, _super);
         function publicClassExtendingPrivateClassInModule() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return publicClassExtendingPrivateClassInModule;
     }(privateClassInPublicModule));
@@ -152,14 +156,16 @@ var publicModule;
     var privateClassExtendingFromPrivateModuleClass = (function (_super) {
         __extends(privateClassExtendingFromPrivateModuleClass, _super);
         function privateClassExtendingFromPrivateModuleClass() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return privateClassExtendingFromPrivateModuleClass;
     }(privateModule.publicClassInPrivateModule));
     var publicClassExtendingFromPrivateModuleClass = (function (_super) {
         __extends(publicClassExtendingFromPrivateModuleClass, _super);
         function publicClassExtendingFromPrivateModuleClass() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return publicClassExtendingFromPrivateModuleClass;
     }(privateModule.publicClassInPrivateModule));
@@ -183,21 +189,24 @@ var privateModule;
     var privateClassExtendingPublicClassInModule = (function (_super) {
         __extends(privateClassExtendingPublicClassInModule, _super);
         function privateClassExtendingPublicClassInModule() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return privateClassExtendingPublicClassInModule;
     }(publicClassInPrivateModule));
     var privateClassExtendingPrivateClassInModule = (function (_super) {
         __extends(privateClassExtendingPrivateClassInModule, _super);
         function privateClassExtendingPrivateClassInModule() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return privateClassExtendingPrivateClassInModule;
     }(privateClassInPrivateModule));
     var publicClassExtendingPublicClassInModule = (function (_super) {
         __extends(publicClassExtendingPublicClassInModule, _super);
         function publicClassExtendingPublicClassInModule() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return publicClassExtendingPublicClassInModule;
     }(publicClassInPrivateModule));
@@ -205,7 +214,8 @@ var privateModule;
     var publicClassExtendingPrivateClassInModule = (function (_super) {
         __extends(publicClassExtendingPrivateClassInModule, _super);
         function publicClassExtendingPrivateClassInModule() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return publicClassExtendingPrivateClassInModule;
     }(privateClassInPrivateModule));
@@ -213,14 +223,16 @@ var privateModule;
     var privateClassExtendingFromPrivateModuleClass = (function (_super) {
         __extends(privateClassExtendingFromPrivateModuleClass, _super);
         function privateClassExtendingFromPrivateModuleClass() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return privateClassExtendingFromPrivateModuleClass;
     }(privateModule.publicClassInPrivateModule));
     var publicClassExtendingFromPrivateModuleClass = (function (_super) {
         __extends(publicClassExtendingFromPrivateModuleClass, _super);
         function publicClassExtendingFromPrivateModuleClass() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return publicClassExtendingFromPrivateModuleClass;
     }(privateModule.publicClassInPrivateModule));
@@ -242,21 +254,24 @@ var privateClass = (function () {
 var privateClassExtendingPublicClass = (function (_super) {
     __extends(privateClassExtendingPublicClass, _super);
     function privateClassExtendingPublicClass() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return privateClassExtendingPublicClass;
 }(publicClass));
 var privateClassExtendingPrivateClassInModule = (function (_super) {
     __extends(privateClassExtendingPrivateClassInModule, _super);
     function privateClassExtendingPrivateClassInModule() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return privateClassExtendingPrivateClassInModule;
 }(privateClass));
 var publicClassExtendingPublicClass = (function (_super) {
     __extends(publicClassExtendingPublicClass, _super);
     function publicClassExtendingPublicClass() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return publicClassExtendingPublicClass;
 }(publicClass));
@@ -264,7 +279,8 @@ exports.publicClassExtendingPublicClass = publicClassExtendingPublicClass;
 var publicClassExtendingPrivateClass = (function (_super) {
     __extends(publicClassExtendingPrivateClass, _super);
     function publicClassExtendingPrivateClass() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return publicClassExtendingPrivateClass;
 }(privateClass));
@@ -272,14 +288,16 @@ exports.publicClassExtendingPrivateClass = publicClassExtendingPrivateClass;
 var privateClassExtendingFromPrivateModuleClass = (function (_super) {
     __extends(privateClassExtendingFromPrivateModuleClass, _super);
     function privateClassExtendingFromPrivateModuleClass() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return privateClassExtendingFromPrivateModuleClass;
 }(privateModule.publicClassInPrivateModule));
 var publicClassExtendingFromPrivateModuleClass = (function (_super) {
     __extends(publicClassExtendingFromPrivateModuleClass, _super);
     function publicClassExtendingFromPrivateModuleClass() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return publicClassExtendingFromPrivateModuleClass;
 }(privateModule.publicClassInPrivateModule));
@@ -308,21 +326,24 @@ var publicModuleInGlobal;
     var privateClassExtendingPublicClassInModule = (function (_super) {
         __extends(privateClassExtendingPublicClassInModule, _super);
         function privateClassExtendingPublicClassInModule() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return privateClassExtendingPublicClassInModule;
     }(publicClassInPublicModule));
     var privateClassExtendingPrivateClassInModule = (function (_super) {
         __extends(privateClassExtendingPrivateClassInModule, _super);
         function privateClassExtendingPrivateClassInModule() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return privateClassExtendingPrivateClassInModule;
     }(privateClassInPublicModule));
     var publicClassExtendingPublicClassInModule = (function (_super) {
         __extends(publicClassExtendingPublicClassInModule, _super);
         function publicClassExtendingPublicClassInModule() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return publicClassExtendingPublicClassInModule;
     }(publicClassInPublicModule));
@@ -330,7 +351,8 @@ var publicModuleInGlobal;
     var publicClassExtendingPrivateClassInModule = (function (_super) {
         __extends(publicClassExtendingPrivateClassInModule, _super);
         function publicClassExtendingPrivateClassInModule() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return publicClassExtendingPrivateClassInModule;
     }(privateClassInPublicModule));
@@ -344,7 +366,8 @@ var publicClassInGlobal = (function () {
 var publicClassExtendingPublicClassInGlobal = (function (_super) {
     __extends(publicClassExtendingPublicClassInGlobal, _super);
     function publicClassExtendingPublicClassInGlobal() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return publicClassExtendingPublicClassInGlobal;
 }(publicClassInGlobal));
diff --git a/tests/baselines/reference/privacyGloClass.js b/tests/baselines/reference/privacyGloClass.js
index e8c8c447cf9..481a3921921 100644
--- a/tests/baselines/reference/privacyGloClass.js
+++ b/tests/baselines/reference/privacyGloClass.js
@@ -84,21 +84,24 @@ var m1;
     var m1_C1_private = (function (_super) {
         __extends(m1_C1_private, _super);
         function m1_C1_private() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return m1_C1_private;
     }(m1_c_public));
     var m1_C2_private = (function (_super) {
         __extends(m1_C2_private, _super);
         function m1_C2_private() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return m1_C2_private;
     }(m1_c_private));
     var m1_C3_public = (function (_super) {
         __extends(m1_C3_public, _super);
         function m1_C3_public() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return m1_C3_public;
     }(m1_c_public));
@@ -106,7 +109,8 @@ var m1;
     var m1_C4_public = (function (_super) {
         __extends(m1_C4_public, _super);
         function m1_C4_public() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return m1_C4_public;
     }(m1_c_private));
@@ -136,21 +140,24 @@ var m1;
     var m1_C9_private = (function (_super) {
         __extends(m1_C9_private, _super);
         function m1_C9_private() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return m1_C9_private;
     }(m1_c_public));
     var m1_C10_private = (function (_super) {
         __extends(m1_C10_private, _super);
         function m1_C10_private() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return m1_C10_private;
     }(m1_c_private));
     var m1_C11_public = (function (_super) {
         __extends(m1_C11_public, _super);
         function m1_C11_public() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return m1_C11_public;
     }(m1_c_public));
@@ -158,7 +165,8 @@ var m1;
     var m1_C12_public = (function (_super) {
         __extends(m1_C12_public, _super);
         function m1_C12_public() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return m1_C12_public;
     }(m1_c_private));
@@ -174,7 +182,8 @@ var glo_c_public = (function () {
 var glo_C3_public = (function (_super) {
     __extends(glo_C3_public, _super);
     function glo_C3_public() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return glo_C3_public;
 }(glo_c_public));
@@ -186,7 +195,8 @@ var glo_C7_public = (function () {
 var glo_C11_public = (function (_super) {
     __extends(glo_C11_public, _super);
     function glo_C11_public() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return glo_C11_public;
 }(glo_c_public));
diff --git a/tests/baselines/reference/privateAccessInSubclass1.js b/tests/baselines/reference/privateAccessInSubclass1.js
index 188c3149fd0..ca432ee7ab7 100644
--- a/tests/baselines/reference/privateAccessInSubclass1.js
+++ b/tests/baselines/reference/privateAccessInSubclass1.js
@@ -23,7 +23,8 @@ var Base = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     D.prototype.myMethod = function () {
         this.options;
diff --git a/tests/baselines/reference/privateInstanceMemberAccessibility.js b/tests/baselines/reference/privateInstanceMemberAccessibility.js
index 8fbe5121136..cfdc137aedf 100644
--- a/tests/baselines/reference/privateInstanceMemberAccessibility.js
+++ b/tests/baselines/reference/privateInstanceMemberAccessibility.js
@@ -27,7 +27,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.x = _super.prototype.foo; // error
         this.z = _super.prototype.foo; // error
     }
diff --git a/tests/baselines/reference/privateProtectedMembersAreNotAccessibleDestructuring.js b/tests/baselines/reference/privateProtectedMembersAreNotAccessibleDestructuring.js
index 058a6ba1b65..8b516a5a19c 100644
--- a/tests/baselines/reference/privateProtectedMembersAreNotAccessibleDestructuring.js
+++ b/tests/baselines/reference/privateProtectedMembersAreNotAccessibleDestructuring.js
@@ -40,7 +40,8 @@ var K = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     C.prototype.m2 = function () {
         var a = this.priv; // error
diff --git a/tests/baselines/reference/privateStaticMemberAccessibility.js b/tests/baselines/reference/privateStaticMemberAccessibility.js
index 352256ac9bd..aad41d01b07 100644
--- a/tests/baselines/reference/privateStaticMemberAccessibility.js
+++ b/tests/baselines/reference/privateStaticMemberAccessibility.js
@@ -22,7 +22,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.bing = function () { return Base.foo; }; // error
     }
     return Derived;
diff --git a/tests/baselines/reference/privateStaticNotAccessibleInClodule2.js b/tests/baselines/reference/privateStaticNotAccessibleInClodule2.js
index 7ed6f3d6792..44adec751bf 100644
--- a/tests/baselines/reference/privateStaticNotAccessibleInClodule2.js
+++ b/tests/baselines/reference/privateStaticNotAccessibleInClodule2.js
@@ -29,7 +29,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/project/privacyCheckOnImportedModuleDeclarationsInsideModule/amd/testGlo.js b/tests/baselines/reference/project/privacyCheckOnImportedModuleDeclarationsInsideModule/amd/testGlo.js
index 3b6e407d045..ed9768b06c2 100644
--- a/tests/baselines/reference/project/privacyCheckOnImportedModuleDeclarationsInsideModule/amd/testGlo.js
+++ b/tests/baselines/reference/project/privacyCheckOnImportedModuleDeclarationsInsideModule/amd/testGlo.js
@@ -14,7 +14,8 @@ var m2;
     var class1 = (function (_super) {
         __extends(class1, _super);
         function class1() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return class1;
     }(m2.mExported.me.class1));
@@ -27,7 +28,8 @@ var m2;
     var class2 = (function (_super) {
         __extends(class2, _super);
         function class2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return class2;
     }(m2.mExported.me.class1));
@@ -40,7 +42,8 @@ var m2;
     var class3 = (function (_super) {
         __extends(class3, _super);
         function class3() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return class3;
     }(mNonExported.mne.class1));
@@ -53,7 +56,8 @@ var m2;
     var class4 = (function (_super) {
         __extends(class4, _super);
         function class4() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return class4;
     }(mNonExported.mne.class1));
diff --git a/tests/baselines/reference/project/privacyCheckOnImportedModuleDeclarationsInsideModule/node/testGlo.js b/tests/baselines/reference/project/privacyCheckOnImportedModuleDeclarationsInsideModule/node/testGlo.js
index 3b6e407d045..ed9768b06c2 100644
--- a/tests/baselines/reference/project/privacyCheckOnImportedModuleDeclarationsInsideModule/node/testGlo.js
+++ b/tests/baselines/reference/project/privacyCheckOnImportedModuleDeclarationsInsideModule/node/testGlo.js
@@ -14,7 +14,8 @@ var m2;
     var class1 = (function (_super) {
         __extends(class1, _super);
         function class1() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return class1;
     }(m2.mExported.me.class1));
@@ -27,7 +28,8 @@ var m2;
     var class2 = (function (_super) {
         __extends(class2, _super);
         function class2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return class2;
     }(m2.mExported.me.class1));
@@ -40,7 +42,8 @@ var m2;
     var class3 = (function (_super) {
         __extends(class3, _super);
         function class3() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return class3;
     }(mNonExported.mne.class1));
@@ -53,7 +56,8 @@ var m2;
     var class4 = (function (_super) {
         __extends(class4, _super);
         function class4() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return class4;
     }(mNonExported.mne.class1));
diff --git a/tests/baselines/reference/project/prologueEmit/amd/out.js b/tests/baselines/reference/project/prologueEmit/amd/out.js
index 6a07c9a92ca..deb73448794 100644
--- a/tests/baselines/reference/project/prologueEmit/amd/out.js
+++ b/tests/baselines/reference/project/prologueEmit/amd/out.js
@@ -18,7 +18,8 @@ var m;
     var child = (function (_super) {
         __extends(child, _super);
         function child() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return child;
     }(base));
diff --git a/tests/baselines/reference/project/prologueEmit/node/out.js b/tests/baselines/reference/project/prologueEmit/node/out.js
index 6a07c9a92ca..deb73448794 100644
--- a/tests/baselines/reference/project/prologueEmit/node/out.js
+++ b/tests/baselines/reference/project/prologueEmit/node/out.js
@@ -18,7 +18,8 @@ var m;
     var child = (function (_super) {
         __extends(child, _super);
         function child() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return child;
     }(base));
diff --git a/tests/baselines/reference/project/quotesInFileAndDirectoryNames/amd/m'ain.js b/tests/baselines/reference/project/quotesInFileAndDirectoryNames/amd/m'ain.js
index 64a207a7cad..b5147a28919 100644
--- a/tests/baselines/reference/project/quotesInFileAndDirectoryNames/amd/m'ain.js
+++ b/tests/baselines/reference/project/quotesInFileAndDirectoryNames/amd/m'ain.js
@@ -7,7 +7,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var ClassC = (function (_super) {
     __extends(ClassC, _super);
     function ClassC() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return ClassC;
 }(test.ClassA));
diff --git a/tests/baselines/reference/project/quotesInFileAndDirectoryNames/node/m'ain.js b/tests/baselines/reference/project/quotesInFileAndDirectoryNames/node/m'ain.js
index 64a207a7cad..b5147a28919 100644
--- a/tests/baselines/reference/project/quotesInFileAndDirectoryNames/node/m'ain.js
+++ b/tests/baselines/reference/project/quotesInFileAndDirectoryNames/node/m'ain.js
@@ -7,7 +7,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var ClassC = (function (_super) {
     __extends(ClassC, _super);
     function ClassC() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return ClassC;
 }(test.ClassA));
diff --git a/tests/baselines/reference/propertiesAndIndexers.js b/tests/baselines/reference/propertiesAndIndexers.js
index 591c4760e58..a22f9663754 100644
--- a/tests/baselines/reference/propertiesAndIndexers.js
+++ b/tests/baselines/reference/propertiesAndIndexers.js
@@ -65,7 +65,8 @@ var P = (function () {
 var Q = (function (_super) {
     __extends(Q, _super);
     function Q() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Q;
 }(P));
diff --git a/tests/baselines/reference/propertyAccess.js b/tests/baselines/reference/propertyAccess.js
index 2dbb316d848..31b90bcf7ac 100644
--- a/tests/baselines/reference/propertyAccess.js
+++ b/tests/baselines/reference/propertyAccess.js
@@ -164,7 +164,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/propertyAccessOnTypeParameterWithConstraints2.js b/tests/baselines/reference/propertyAccessOnTypeParameterWithConstraints2.js
index bbd2def2206..c570642a1ba 100644
--- a/tests/baselines/reference/propertyAccessOnTypeParameterWithConstraints2.js
+++ b/tests/baselines/reference/propertyAccessOnTypeParameterWithConstraints2.js
@@ -97,7 +97,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     B.prototype.bar = function () {
         return '';
diff --git a/tests/baselines/reference/propertyAccessOnTypeParameterWithConstraints3.js b/tests/baselines/reference/propertyAccessOnTypeParameterWithConstraints3.js
index 76da06166d4..aebdc2c3ce3 100644
--- a/tests/baselines/reference/propertyAccessOnTypeParameterWithConstraints3.js
+++ b/tests/baselines/reference/propertyAccessOnTypeParameterWithConstraints3.js
@@ -72,7 +72,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     B.prototype.bar = function () {
         return '';
diff --git a/tests/baselines/reference/propertyAccessOnTypeParameterWithConstraints5.js b/tests/baselines/reference/propertyAccessOnTypeParameterWithConstraints5.js
index c49153c59b0..442ae29e278 100644
--- a/tests/baselines/reference/propertyAccessOnTypeParameterWithConstraints5.js
+++ b/tests/baselines/reference/propertyAccessOnTypeParameterWithConstraints5.js
@@ -59,7 +59,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     B.prototype.bar = function () {
         return '';
diff --git a/tests/baselines/reference/protectedClassPropertyAccessibleWithinNestedSubclass.js b/tests/baselines/reference/protectedClassPropertyAccessibleWithinNestedSubclass.js
index 255c05ac3ac..40a1365b7e1 100644
--- a/tests/baselines/reference/protectedClassPropertyAccessibleWithinNestedSubclass.js
+++ b/tests/baselines/reference/protectedClassPropertyAccessibleWithinNestedSubclass.js
@@ -52,7 +52,8 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Object.defineProperty(C.prototype, "y", {
         get: function () { return this.x; },
@@ -93,7 +94,8 @@ var C = (function (_super) {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return E;
 }(C));
diff --git a/tests/baselines/reference/protectedClassPropertyAccessibleWithinNestedSubclass1.js b/tests/baselines/reference/protectedClassPropertyAccessibleWithinNestedSubclass1.js
index 02ad29bd312..e6c768a6759 100644
--- a/tests/baselines/reference/protectedClassPropertyAccessibleWithinNestedSubclass1.js
+++ b/tests/baselines/reference/protectedClassPropertyAccessibleWithinNestedSubclass1.js
@@ -147,7 +147,8 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived1.prototype.method1 = function () {
         var B = (function () {
@@ -173,7 +174,8 @@ var Derived1 = (function (_super) {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived2.prototype.method2 = function () {
         var C = (function () {
@@ -199,7 +201,8 @@ var Derived2 = (function (_super) {
 var Derived3 = (function (_super) {
     __extends(Derived3, _super);
     function Derived3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived3.prototype.method3 = function () {
         var D = (function () {
@@ -225,7 +228,8 @@ var Derived3 = (function (_super) {
 var Derived4 = (function (_super) {
     __extends(Derived4, _super);
     function Derived4() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived4.prototype.method4 = function () {
         var E = (function () {
diff --git a/tests/baselines/reference/protectedClassPropertyAccessibleWithinSubclass.js b/tests/baselines/reference/protectedClassPropertyAccessibleWithinSubclass.js
index a87f67e15f2..3f46b69ecf3 100644
--- a/tests/baselines/reference/protectedClassPropertyAccessibleWithinSubclass.js
+++ b/tests/baselines/reference/protectedClassPropertyAccessibleWithinSubclass.js
@@ -34,7 +34,8 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Object.defineProperty(C.prototype, "y", {
         get: function () { return this.x; },
diff --git a/tests/baselines/reference/protectedClassPropertyAccessibleWithinSubclass2.js b/tests/baselines/reference/protectedClassPropertyAccessibleWithinSubclass2.js
index 05dc85e251e..44a4fbdf284 100644
--- a/tests/baselines/reference/protectedClassPropertyAccessibleWithinSubclass2.js
+++ b/tests/baselines/reference/protectedClassPropertyAccessibleWithinSubclass2.js
@@ -120,7 +120,8 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived1.prototype.method1 = function () {
         var b;
@@ -139,7 +140,8 @@ var Derived1 = (function (_super) {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived2.prototype.method2 = function () {
         var b;
@@ -158,7 +160,8 @@ var Derived2 = (function (_super) {
 var Derived3 = (function (_super) {
     __extends(Derived3, _super);
     function Derived3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived3.prototype.method3 = function () {
         var b;
@@ -177,7 +180,8 @@ var Derived3 = (function (_super) {
 var Derived4 = (function (_super) {
     __extends(Derived4, _super);
     function Derived4() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived4.prototype.method4 = function () {
         var b;
diff --git a/tests/baselines/reference/protectedClassPropertyAccessibleWithinSubclass3.js b/tests/baselines/reference/protectedClassPropertyAccessibleWithinSubclass3.js
index 6675589226e..4cc09bac99d 100644
--- a/tests/baselines/reference/protectedClassPropertyAccessibleWithinSubclass3.js
+++ b/tests/baselines/reference/protectedClassPropertyAccessibleWithinSubclass3.js
@@ -30,7 +30,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived.prototype.method1 = function () {
         this.x; // OK, accessed within a subclass of the declaring class
diff --git a/tests/baselines/reference/protectedInstanceMemberAccessibility.js b/tests/baselines/reference/protectedInstanceMemberAccessibility.js
index eba89aac28e..003e2f50e6f 100644
--- a/tests/baselines/reference/protectedInstanceMemberAccessibility.js
+++ b/tests/baselines/reference/protectedInstanceMemberAccessibility.js
@@ -61,7 +61,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     B.prototype.g = function () {
         var t1 = this.x;
@@ -93,7 +94,8 @@ var B = (function (_super) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/protectedMembers.js b/tests/baselines/reference/protectedMembers.js
index dcc68e0c946..984527b2c0d 100644
--- a/tests/baselines/reference/protectedMembers.js
+++ b/tests/baselines/reference/protectedMembers.js
@@ -137,7 +137,8 @@ var C1 = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     C2.prototype.f = function () {
         return _super.prototype.f.call(this) + this.x;
@@ -151,7 +152,8 @@ var C2 = (function (_super) {
 var C3 = (function (_super) {
     __extends(C3, _super);
     function C3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     C3.prototype.f = function () {
         return _super.prototype.f.call(this);
@@ -187,14 +189,16 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     C.foo = function (a, b, c, d, e) {
         a.x = 1; // Error, access must be through C or type derived from C
@@ -208,7 +212,8 @@ var C = (function (_super) {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(C));
@@ -239,7 +244,8 @@ var A2 = (function () {
 var B2 = (function (_super) {
     __extends(B2, _super);
     function B2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B2;
 }(A2));
@@ -252,7 +258,8 @@ var A3 = (function () {
 var B3 = (function (_super) {
     __extends(B3, _super);
     function B3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B3;
 }(A3));
diff --git a/tests/baselines/reference/protectedStaticClassPropertyAccessibleWithinSubclass.js b/tests/baselines/reference/protectedStaticClassPropertyAccessibleWithinSubclass.js
index 323a5a2f2b6..a272ad42fa1 100644
--- a/tests/baselines/reference/protectedStaticClassPropertyAccessibleWithinSubclass.js
+++ b/tests/baselines/reference/protectedStaticClassPropertyAccessibleWithinSubclass.js
@@ -63,7 +63,8 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived1.staticMethod1 = function () {
         Base.x; // OK, accessed within a class derived from their declaring class
@@ -76,7 +77,8 @@ var Derived1 = (function (_super) {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived2.staticMethod2 = function () {
         Base.x; // OK, accessed within a class derived from their declaring class
@@ -89,7 +91,8 @@ var Derived2 = (function (_super) {
 var Derived3 = (function (_super) {
     __extends(Derived3, _super);
     function Derived3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived3.staticMethod3 = function () {
         Base.x; // OK, accessed within a class derived from their declaring class
diff --git a/tests/baselines/reference/protectedStaticClassPropertyAccessibleWithinSubclass2.js b/tests/baselines/reference/protectedStaticClassPropertyAccessibleWithinSubclass2.js
index 1295dc7448e..2add5e7e154 100644
--- a/tests/baselines/reference/protectedStaticClassPropertyAccessibleWithinSubclass2.js
+++ b/tests/baselines/reference/protectedStaticClassPropertyAccessibleWithinSubclass2.js
@@ -38,7 +38,8 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived1.staticMethod1 = function () {
         this.x; // OK, accessed within a class derived from their declaring class
@@ -49,7 +50,8 @@ var Derived1 = (function (_super) {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived2.staticMethod3 = function () {
         this.x; // OK, accessed within a class derived from their declaring class
diff --git a/tests/baselines/reference/qualifiedName_entity-name-resolution-does-not-affect-class-heritage.js b/tests/baselines/reference/qualifiedName_entity-name-resolution-does-not-affect-class-heritage.js
index f396c2483e8..225acf74bbe 100644
--- a/tests/baselines/reference/qualifiedName_entity-name-resolution-does-not-affect-class-heritage.js
+++ b/tests/baselines/reference/qualifiedName_entity-name-resolution-does-not-affect-class-heritage.js
@@ -19,7 +19,8 @@ var Alpha;
 var Beta = (function (_super) {
     __extends(Beta, _super);
     function Beta() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Beta;
 }(Alpha.x));
diff --git a/tests/baselines/reference/readonlyConstructorAssignment.js b/tests/baselines/reference/readonlyConstructorAssignment.js
index 40c292e4ce8..1c1e2a94ff1 100644
--- a/tests/baselines/reference/readonlyConstructorAssignment.js
+++ b/tests/baselines/reference/readonlyConstructorAssignment.js
@@ -56,7 +56,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B(x) {
-        _super.call(this, x);
+        var _this;
+        _this = _super.call(this, x) || this;
         // Fails, x is readonly
         this.x = 1;
     }
@@ -67,7 +68,8 @@ var C = (function (_super) {
     // This is the usual behavior of readonly properties:
     // if one is redeclared in a base class, then it can be assigned to.
     function C(x) {
-        _super.call(this, x);
+        var _this;
+        _this = _super.call(this, x) || this;
         this.x = x;
         this.x = 1;
     }
@@ -84,7 +86,8 @@ var D = (function () {
 var E = (function (_super) {
     __extends(E, _super);
     function E(x) {
-        _super.call(this, x);
+        var _this;
+        _this = _super.call(this, x) || this;
         this.x = x;
         this.x = 1;
     }
diff --git a/tests/baselines/reference/recursiveBaseCheck3.js b/tests/baselines/reference/recursiveBaseCheck3.js
index b032ce6774d..5b3e829d2e6 100644
--- a/tests/baselines/reference/recursiveBaseCheck3.js
+++ b/tests/baselines/reference/recursiveBaseCheck3.js
@@ -13,14 +13,16 @@ var __extends = (this && this.__extends) || function (d, b) {
 var A = (function (_super) {
     __extends(A, _super);
     function A() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return A;
 }(C));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/recursiveBaseCheck4.js b/tests/baselines/reference/recursiveBaseCheck4.js
index 07ba40c68b1..b515c7ab318 100644
--- a/tests/baselines/reference/recursiveBaseCheck4.js
+++ b/tests/baselines/reference/recursiveBaseCheck4.js
@@ -11,7 +11,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var M = (function (_super) {
     __extends(M, _super);
     function M() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return M;
 }(M));
diff --git a/tests/baselines/reference/recursiveBaseCheck6.js b/tests/baselines/reference/recursiveBaseCheck6.js
index 5b880c294b7..1871eff20d4 100644
--- a/tests/baselines/reference/recursiveBaseCheck6.js
+++ b/tests/baselines/reference/recursiveBaseCheck6.js
@@ -11,7 +11,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var S18 = (function (_super) {
     __extends(S18, _super);
     function S18() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return S18;
 }(S18));
diff --git a/tests/baselines/reference/recursiveBaseConstructorCreation1.js b/tests/baselines/reference/recursiveBaseConstructorCreation1.js
index dd79ba068bb..c2f884aa8e4 100644
--- a/tests/baselines/reference/recursiveBaseConstructorCreation1.js
+++ b/tests/baselines/reference/recursiveBaseConstructorCreation1.js
@@ -21,7 +21,8 @@ var C1 = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }(C1));
diff --git a/tests/baselines/reference/recursiveClassInstantiationsWithDefaultConstructors.js b/tests/baselines/reference/recursiveClassInstantiationsWithDefaultConstructors.js
index 62e5958715e..f84c7ad3dae 100644
--- a/tests/baselines/reference/recursiveClassInstantiationsWithDefaultConstructors.js
+++ b/tests/baselines/reference/recursiveClassInstantiationsWithDefaultConstructors.js
@@ -28,7 +28,8 @@ var TypeScript2;
     var MemberNameArray = (function (_super) {
         __extends(MemberNameArray, _super);
         function MemberNameArray() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return MemberNameArray;
     }(MemberName));
diff --git a/tests/baselines/reference/recursiveClassReferenceTest.js b/tests/baselines/reference/recursiveClassReferenceTest.js
index 3aa066d158d..2baa854e462 100644
--- a/tests/baselines/reference/recursiveClassReferenceTest.js
+++ b/tests/baselines/reference/recursiveClassReferenceTest.js
@@ -190,7 +190,8 @@ var Sample;
                 var Mode = (function (_super) {
                     __extends(Mode, _super);
                     function Mode() {
-                        _super.apply(this, arguments);
+                        var _this = _super.apply(this, arguments) || this;
+                        return _this;
                     }
                     // scenario 2
                     Mode.prototype.getInitialState = function () {
diff --git a/tests/baselines/reference/recursiveClassReferenceTest.js.map b/tests/baselines/reference/recursiveClassReferenceTest.js.map
index 7e0b27b82b4..56c0fc4e6eb 100644
--- a/tests/baselines/reference/recursiveClassReferenceTest.js.map
+++ b/tests/baselines/reference/recursiveClassReferenceTest.js.map
@@ -1,2 +1,2 @@
 //// [recursiveClassReferenceTest.js.map]
-{"version":3,"file":"recursiveClassReferenceTest.js","sourceRoot":"","sources":["recursiveClassReferenceTest.ts"],"names":[],"mappings":"AAAA,iEAAiE;AACjE,0EAA0E;;;;;;AA8B1E,IAAO,MAAM,CAUZ;AAVD,WAAO,MAAM;IAAC,IAAA,OAAO,CAUpB;IAVa,WAAA,OAAO;QAAC,IAAA,KAAK,CAU1B;QAVqB,WAAA,OAAK;YAAC,IAAA,IAAI,CAU/B;YAV2B,WAAA,IAAI;gBAC/B;oBAAA;oBAQA,CAAC;oBANO,+BAAK,GAAZ,cAAiB,MAAM,CAAC,IAAI,CAAC,CAAC,CAAC;oBAExB,6BAAG,GAAV,UAAW,KAA6B;wBAEvC,MAAM,CAAC,IAAI,CAAC;oBACb,CAAC;oBACF,sBAAC;gBAAD,CAAC,AARD,IAQC;gBARY,oBAAe,kBAQ3B,CAAA;YACF,CAAC,EAV2B,IAAI,GAAJ,YAAI,KAAJ,YAAI,QAU/B;QAAD,CAAC,EAVqB,KAAK,GAAL,aAAK,KAAL,aAAK,QAU1B;IAAD,CAAC,EAVa,OAAO,GAAP,cAAO,KAAP,cAAO,QAUpB;AAAD,CAAC,EAVM,MAAM,KAAN,MAAM,QAUZ;AAED,IAAO,MAAM,CAoBZ;AApBD,WAAO,MAAM;IAAC,IAAA,KAAK,CAoBlB;IApBa,WAAA,KAAK;QAAC,IAAA,OAAO,CAoB1B;QApBmB,WAAA,OAAO;YAC1B;gBAKC,oBAAoB,SAAkC;oBAAlC,cAAS,GAAT,SAAS,CAAyB;oBAD9C,YAAO,GAAO,IAAI,CAAC;oBAEvB,aAAa;oBACb,SAAS,CAAC,SAAS,CAAC,WAAW,EAAE,IAAI,CAAC,CAAC;gBAC3C,CAAC;gBANM,wBAAG,GAAV,UAAW,MAAyC,IAAI,EAAE,CAAC,CAAC,IAAI,CAAC,CAAC,CAAC;oBAAA,MAAM,CAAC,MAAM,CAAC,IAAI,CAAC,CAAC;gBAAA,CAAC,CAAA,CAAC;gBAQlF,+BAAU,GAAjB;oBACC,MAAM,CAAC,OAAO,CAAC;gBAChB,CAAC;gBAEM,4BAAO,GAAd;gBAEA,CAAC;gBAEF,iBAAC;YAAD,CAAC,AAlBD,IAkBC;YAlBY,kBAAU,aAkBtB,CAAA;QACF,CAAC,EApBmB,OAAO,GAAP,aAAO,KAAP,aAAO,QAoB1B;IAAD,CAAC,EApBa,KAAK,GAAL,YAAK,KAAL,YAAK,QAoBlB;AAAD,CAAC,EApBM,MAAM,KAAN,MAAM,QAoBZ;AAGD;IAAA;IAAuF,CAAC;IAA3C,sCAAe,GAAtB,cAAmC,MAAM,CAAC,IAAI,CAAC,CAAA,CAAC;IAAC,mBAAC;AAAD,CAAC,AAAxF,IAAwF;AASxF,IAAO,MAAM,CAwBZ;AAxBD,WAAO,MAAM;IAAC,IAAA,KAAK,CAwBlB;IAxBa,WAAA,KAAK;QAAC,IAAA,SAAS,CAwB5B;QAxBmB,WAAA,SAAS;YAAC,IAAA,SAAS,CAwBtC;YAxB6B,WAAA,SAAS;gBAEtC;oBACO,eAAoB,IAAW;wBAAX,SAAI,GAAJ,IAAI,CAAO;oBAAI,CAAC;oBACnC,qBAAK,GAAZ;wBACC,MAAM,CAAC,IAAI,CAAC;oBACb,CAAC;oBAEM,sBAAM,GAAb,UAAc,KAAY;wBACzB,MAAM,CAAC,IAAI,KAAK,KAAK,CAAC;oBACvB,CAAC;oBAEM,uBAAO,GAAd,cAA0B,MAAM,CAAC,IAAI,CAAC,CAAC,CAAC;oBACzC,YAAC;gBAAD,CAAC,AAXD,IAWC;gBAXY,eAAK,QAWjB,CAAA;gBAED;oBAA0B,wBAAY;oBAAtC;wBAA0B,8BAAY;oBAQtC,CAAC;oBANA,aAAa;oBACN,8BAAe,GAAtB;wBACC,MAAM,CAAC,IAAI,KAAK,CAAC,IAAI,CAAC,CAAC;oBACxB,CAAC;oBAGF,WAAC;gBAAD,CAAC,AARD,CAA0B,YAAY,GAQrC;gBARY,cAAI,OAQhB,CAAA;YACF,CAAC,EAxB6B,SAAS,GAAT,mBAAS,KAAT,mBAAS,QAwBtC;QAAD,CAAC,EAxBmB,SAAS,GAAT,eAAS,KAAT,eAAS,QAwB5B;IAAD,CAAC,EAxBa,KAAK,GAAL,YAAK,KAAL,YAAK,QAwBlB;AAAD,CAAC,EAxBM,MAAM,KAAN,MAAM,QAwBZ"}
\ No newline at end of file
+{"version":3,"file":"recursiveClassReferenceTest.js","sourceRoot":"","sources":["recursiveClassReferenceTest.ts"],"names":[],"mappings":"AAAA,iEAAiE;AACjE,0EAA0E;;;;;;AA8B1E,IAAO,MAAM,CAUZ;AAVD,WAAO,MAAM;IAAC,IAAA,OAAO,CAUpB;IAVa,WAAA,OAAO;QAAC,IAAA,KAAK,CAU1B;QAVqB,WAAA,OAAK;YAAC,IAAA,IAAI,CAU/B;YAV2B,WAAA,IAAI;gBAC/B;oBAAA;oBAQA,CAAC;oBANO,+BAAK,GAAZ,cAAiB,MAAM,CAAC,IAAI,CAAC,CAAC,CAAC;oBAExB,6BAAG,GAAV,UAAW,KAA6B;wBAEvC,MAAM,CAAC,IAAI,CAAC;oBACb,CAAC;oBACF,sBAAC;gBAAD,CAAC,AARD,IAQC;gBARY,oBAAe,kBAQ3B,CAAA;YACF,CAAC,EAV2B,IAAI,GAAJ,YAAI,KAAJ,YAAI,QAU/B;QAAD,CAAC,EAVqB,KAAK,GAAL,aAAK,KAAL,aAAK,QAU1B;IAAD,CAAC,EAVa,OAAO,GAAP,cAAO,KAAP,cAAO,QAUpB;AAAD,CAAC,EAVM,MAAM,KAAN,MAAM,QAUZ;AAED,IAAO,MAAM,CAoBZ;AApBD,WAAO,MAAM;IAAC,IAAA,KAAK,CAoBlB;IApBa,WAAA,KAAK;QAAC,IAAA,OAAO,CAoB1B;QApBmB,WAAA,OAAO;YAC1B;gBAKC,oBAAoB,SAAkC;oBAAlC,cAAS,GAAT,SAAS,CAAyB;oBAD9C,YAAO,GAAO,IAAI,CAAC;oBAEvB,aAAa;oBACb,SAAS,CAAC,SAAS,CAAC,WAAW,EAAE,IAAI,CAAC,CAAC;gBAC3C,CAAC;gBANM,wBAAG,GAAV,UAAW,MAAyC,IAAI,EAAE,CAAC,CAAC,IAAI,CAAC,CAAC,CAAC;oBAAA,MAAM,CAAC,MAAM,CAAC,IAAI,CAAC,CAAC;gBAAA,CAAC,CAAA,CAAC;gBAQlF,+BAAU,GAAjB;oBACC,MAAM,CAAC,OAAO,CAAC;gBAChB,CAAC;gBAEM,4BAAO,GAAd;gBAEA,CAAC;gBAEF,iBAAC;YAAD,CAAC,AAlBD,IAkBC;YAlBY,kBAAU,aAkBtB,CAAA;QACF,CAAC,EApBmB,OAAO,GAAP,aAAO,KAAP,aAAO,QAoB1B;IAAD,CAAC,EApBa,KAAK,GAAL,YAAK,KAAL,YAAK,QAoBlB;AAAD,CAAC,EApBM,MAAM,KAAN,MAAM,QAoBZ;AAGD;IAAA;IAAuF,CAAC;IAA3C,sCAAe,GAAtB,cAAmC,MAAM,CAAC,IAAI,CAAC,CAAA,CAAC;IAAC,mBAAC;AAAD,CAAC,AAAxF,IAAwF;AASxF,IAAO,MAAM,CAwBZ;AAxBD,WAAO,MAAM;IAAC,IAAA,KAAK,CAwBlB;IAxBa,WAAA,KAAK;QAAC,IAAA,SAAS,CAwB5B;QAxBmB,WAAA,SAAS;YAAC,IAAA,SAAS,CAwBtC;YAxB6B,WAAA,SAAS;gBAEtC;oBACO,eAAoB,IAAW;wBAAX,SAAI,GAAJ,IAAI,CAAO;oBAAI,CAAC;oBACnC,qBAAK,GAAZ;wBACC,MAAM,CAAC,IAAI,CAAC;oBACb,CAAC;oBAEM,sBAAM,GAAb,UAAc,KAAY;wBACzB,MAAM,CAAC,IAAI,KAAK,KAAK,CAAC;oBACvB,CAAC;oBAEM,uBAAO,GAAd,cAA0B,MAAM,CAAC,IAAI,CAAC,CAAC,CAAC;oBACzC,YAAC;gBAAD,CAAC,AAXD,IAWC;gBAXY,eAAK,QAWjB,CAAA;gBAED;oBAA0B,wBAAY;oBAAtC;wBAA0B,kDAAY;;oBAQtC,CAAC;oBANA,aAAa;oBACN,8BAAe,GAAtB;wBACC,MAAM,CAAC,IAAI,KAAK,CAAC,IAAI,CAAC,CAAC;oBACxB,CAAC;oBAGF,WAAC;gBAAD,CAAC,AARD,CAA0B,YAAY,GAQrC;gBARY,cAAI,OAQhB,CAAA;YACF,CAAC,EAxB6B,SAAS,GAAT,mBAAS,KAAT,mBAAS,QAwBtC;QAAD,CAAC,EAxBmB,SAAS,GAAT,eAAS,KAAT,eAAS,QAwB5B;IAAD,CAAC,EAxBa,KAAK,GAAL,YAAK,KAAL,YAAK,QAwBlB;AAAD,CAAC,EAxBM,MAAM,KAAN,MAAM,QAwBZ"}
\ No newline at end of file
diff --git a/tests/baselines/reference/recursiveClassReferenceTest.sourcemap.txt b/tests/baselines/reference/recursiveClassReferenceTest.sourcemap.txt
index 7e9da7dddf3..9656c078343 100644
--- a/tests/baselines/reference/recursiveClassReferenceTest.sourcemap.txt
+++ b/tests/baselines/reference/recursiveClassReferenceTest.sourcemap.txt
@@ -1692,18 +1692,19 @@ sourceFile:recursiveClassReferenceTest.ts
 ---
 >>>                    function Mode() {
 1 >^^^^^^^^^^^^^^^^^^^^
-2 >                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
+2 >                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
 1 >
 1 >Emitted(87, 21) Source(91, 2) + SourceIndex(0)
 ---
->>>                        _super.apply(this, arguments);
+>>>                        var _this = _super.apply(this, arguments) || this;
 1->^^^^^^^^^^^^^^^^^^^^^^^^
-2 >                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+2 >                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 1->export class Mode extends 
 2 >                        AbstractMode
 1->Emitted(88, 25) Source(91, 28) + SourceIndex(0)
-2 >Emitted(88, 55) Source(91, 40) + SourceIndex(0)
+2 >Emitted(88, 75) Source(91, 40) + SourceIndex(0)
 ---
+>>>                        return _this;
 >>>                    }
 1 >^^^^^^^^^^^^^^^^^^^^
 2 >                    ^
@@ -1718,8 +1719,8 @@ sourceFile:recursiveClassReferenceTest.ts
   >
   >	
 2 >                    }
-1 >Emitted(89, 21) Source(99, 2) + SourceIndex(0)
-2 >Emitted(89, 22) Source(99, 3) + SourceIndex(0)
+1 >Emitted(90, 21) Source(99, 2) + SourceIndex(0)
+2 >Emitted(90, 22) Source(99, 3) + SourceIndex(0)
 ---
 >>>                    // scenario 2
 1->^^^^^^^^^^^^^^^^^^^^
@@ -1727,8 +1728,8 @@ sourceFile:recursiveClassReferenceTest.ts
 3 >                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
 1->
 2 >                    // scenario 2
-1->Emitted(90, 21) Source(93, 3) + SourceIndex(0)
-2 >Emitted(90, 34) Source(93, 16) + SourceIndex(0)
+1->Emitted(91, 21) Source(93, 3) + SourceIndex(0)
+2 >Emitted(91, 34) Source(93, 16) + SourceIndex(0)
 ---
 >>>                    Mode.prototype.getInitialState = function () {
 1->^^^^^^^^^^^^^^^^^^^^
@@ -1738,9 +1739,9 @@ sourceFile:recursiveClassReferenceTest.ts
   >		public 
 2 >                    getInitialState
 3 >                                                  
-1->Emitted(91, 21) Source(94, 10) + SourceIndex(0)
-2 >Emitted(91, 51) Source(94, 25) + SourceIndex(0)
-3 >Emitted(91, 54) Source(94, 3) + SourceIndex(0)
+1->Emitted(92, 21) Source(94, 10) + SourceIndex(0)
+2 >Emitted(92, 51) Source(94, 25) + SourceIndex(0)
+3 >Emitted(92, 54) Source(94, 3) + SourceIndex(0)
 ---
 >>>                        return new State(self);
 1 >^^^^^^^^^^^^^^^^^^^^^^^^
@@ -1762,15 +1763,15 @@ sourceFile:recursiveClassReferenceTest.ts
 7 >                                         self
 8 >                                             )
 9 >                                              ;
-1 >Emitted(92, 25) Source(95, 4) + SourceIndex(0)
-2 >Emitted(92, 31) Source(95, 10) + SourceIndex(0)
-3 >Emitted(92, 32) Source(95, 11) + SourceIndex(0)
-4 >Emitted(92, 36) Source(95, 15) + SourceIndex(0)
-5 >Emitted(92, 41) Source(95, 20) + SourceIndex(0)
-6 >Emitted(92, 42) Source(95, 21) + SourceIndex(0)
-7 >Emitted(92, 46) Source(95, 25) + SourceIndex(0)
-8 >Emitted(92, 47) Source(95, 26) + SourceIndex(0)
-9 >Emitted(92, 48) Source(95, 27) + SourceIndex(0)
+1 >Emitted(93, 25) Source(95, 4) + SourceIndex(0)
+2 >Emitted(93, 31) Source(95, 10) + SourceIndex(0)
+3 >Emitted(93, 32) Source(95, 11) + SourceIndex(0)
+4 >Emitted(93, 36) Source(95, 15) + SourceIndex(0)
+5 >Emitted(93, 41) Source(95, 20) + SourceIndex(0)
+6 >Emitted(93, 42) Source(95, 21) + SourceIndex(0)
+7 >Emitted(93, 46) Source(95, 25) + SourceIndex(0)
+8 >Emitted(93, 47) Source(95, 26) + SourceIndex(0)
+9 >Emitted(93, 48) Source(95, 27) + SourceIndex(0)
 ---
 >>>                    };
 1 >^^^^^^^^^^^^^^^^^^^^
@@ -1779,8 +1780,8 @@ sourceFile:recursiveClassReferenceTest.ts
 1 >
   >		
 2 >                    }
-1 >Emitted(93, 21) Source(96, 3) + SourceIndex(0)
-2 >Emitted(93, 22) Source(96, 4) + SourceIndex(0)
+1 >Emitted(94, 21) Source(96, 3) + SourceIndex(0)
+2 >Emitted(94, 22) Source(96, 4) + SourceIndex(0)
 ---
 >>>                    return Mode;
 1->^^^^^^^^^^^^^^^^^^^^
@@ -1791,8 +1792,8 @@ sourceFile:recursiveClassReferenceTest.ts
   >
   >	
 2 >                    }
-1->Emitted(94, 21) Source(99, 2) + SourceIndex(0)
-2 >Emitted(94, 32) Source(99, 3) + SourceIndex(0)
+1->Emitted(95, 21) Source(99, 2) + SourceIndex(0)
+2 >Emitted(95, 32) Source(99, 3) + SourceIndex(0)
 ---
 >>>                }(AbstractMode));
 1->^^^^^^^^^^^^^^^^
@@ -1816,12 +1817,12 @@ sourceFile:recursiveClassReferenceTest.ts
   >                              
   >                              
   >                              	}
-1->Emitted(95, 17) Source(99, 2) + SourceIndex(0)
-2 >Emitted(95, 18) Source(99, 3) + SourceIndex(0)
-3 >Emitted(95, 18) Source(91, 2) + SourceIndex(0)
-4 >Emitted(95, 19) Source(91, 28) + SourceIndex(0)
-5 >Emitted(95, 31) Source(91, 40) + SourceIndex(0)
-6 >Emitted(95, 34) Source(99, 3) + SourceIndex(0)
+1->Emitted(96, 17) Source(99, 2) + SourceIndex(0)
+2 >Emitted(96, 18) Source(99, 3) + SourceIndex(0)
+3 >Emitted(96, 18) Source(91, 2) + SourceIndex(0)
+4 >Emitted(96, 19) Source(91, 28) + SourceIndex(0)
+5 >Emitted(96, 31) Source(91, 40) + SourceIndex(0)
+6 >Emitted(96, 34) Source(99, 3) + SourceIndex(0)
 ---
 >>>                PlainText.Mode = Mode;
 1->^^^^^^^^^^^^^^^^
@@ -1841,10 +1842,10 @@ sourceFile:recursiveClassReferenceTest.ts
   >                              
   >                              	}
 4 >                                     
-1->Emitted(96, 17) Source(91, 15) + SourceIndex(0)
-2 >Emitted(96, 31) Source(91, 19) + SourceIndex(0)
-3 >Emitted(96, 38) Source(99, 3) + SourceIndex(0)
-4 >Emitted(96, 39) Source(99, 3) + SourceIndex(0)
+1->Emitted(97, 17) Source(91, 15) + SourceIndex(0)
+2 >Emitted(97, 31) Source(91, 19) + SourceIndex(0)
+3 >Emitted(97, 38) Source(99, 3) + SourceIndex(0)
+4 >Emitted(97, 39) Source(99, 3) + SourceIndex(0)
 ---
 >>>            })(PlainText = Languages.PlainText || (Languages.PlainText = {}));
 1->^^^^^^^^^^^^
@@ -1890,15 +1891,15 @@ sourceFile:recursiveClassReferenceTest.ts
   >                                                                      
   >                                                                      	}
   >                                                                      }
-1->Emitted(97, 13) Source(100, 1) + SourceIndex(0)
-2 >Emitted(97, 14) Source(100, 2) + SourceIndex(0)
-3 >Emitted(97, 16) Source(76, 31) + SourceIndex(0)
-4 >Emitted(97, 25) Source(76, 40) + SourceIndex(0)
-5 >Emitted(97, 28) Source(76, 31) + SourceIndex(0)
-6 >Emitted(97, 47) Source(76, 40) + SourceIndex(0)
-7 >Emitted(97, 52) Source(76, 31) + SourceIndex(0)
-8 >Emitted(97, 71) Source(76, 40) + SourceIndex(0)
-9 >Emitted(97, 79) Source(100, 2) + SourceIndex(0)
+1->Emitted(98, 13) Source(100, 1) + SourceIndex(0)
+2 >Emitted(98, 14) Source(100, 2) + SourceIndex(0)
+3 >Emitted(98, 16) Source(76, 31) + SourceIndex(0)
+4 >Emitted(98, 25) Source(76, 40) + SourceIndex(0)
+5 >Emitted(98, 28) Source(76, 31) + SourceIndex(0)
+6 >Emitted(98, 47) Source(76, 40) + SourceIndex(0)
+7 >Emitted(98, 52) Source(76, 31) + SourceIndex(0)
+8 >Emitted(98, 71) Source(76, 40) + SourceIndex(0)
+9 >Emitted(98, 79) Source(100, 2) + SourceIndex(0)
 ---
 >>>        })(Languages = Thing.Languages || (Thing.Languages = {}));
 1 >^^^^^^^^
@@ -1943,15 +1944,15 @@ sourceFile:recursiveClassReferenceTest.ts
   >                                                          
   >                                                          	}
   >                                                          }
-1 >Emitted(98, 9) Source(100, 1) + SourceIndex(0)
-2 >Emitted(98, 10) Source(100, 2) + SourceIndex(0)
-3 >Emitted(98, 12) Source(76, 21) + SourceIndex(0)
-4 >Emitted(98, 21) Source(76, 30) + SourceIndex(0)
-5 >Emitted(98, 24) Source(76, 21) + SourceIndex(0)
-6 >Emitted(98, 39) Source(76, 30) + SourceIndex(0)
-7 >Emitted(98, 44) Source(76, 21) + SourceIndex(0)
-8 >Emitted(98, 59) Source(76, 30) + SourceIndex(0)
-9 >Emitted(98, 67) Source(100, 2) + SourceIndex(0)
+1 >Emitted(99, 9) Source(100, 1) + SourceIndex(0)
+2 >Emitted(99, 10) Source(100, 2) + SourceIndex(0)
+3 >Emitted(99, 12) Source(76, 21) + SourceIndex(0)
+4 >Emitted(99, 21) Source(76, 30) + SourceIndex(0)
+5 >Emitted(99, 24) Source(76, 21) + SourceIndex(0)
+6 >Emitted(99, 39) Source(76, 30) + SourceIndex(0)
+7 >Emitted(99, 44) Source(76, 21) + SourceIndex(0)
+8 >Emitted(99, 59) Source(76, 30) + SourceIndex(0)
+9 >Emitted(99, 67) Source(100, 2) + SourceIndex(0)
 ---
 >>>    })(Thing = Sample.Thing || (Sample.Thing = {}));
 1 >^^^^
@@ -1996,15 +1997,15 @@ sourceFile:recursiveClassReferenceTest.ts
   >                                            
   >                                            	}
   >                                            }
-1 >Emitted(99, 5) Source(100, 1) + SourceIndex(0)
-2 >Emitted(99, 6) Source(100, 2) + SourceIndex(0)
-3 >Emitted(99, 8) Source(76, 15) + SourceIndex(0)
-4 >Emitted(99, 13) Source(76, 20) + SourceIndex(0)
-5 >Emitted(99, 16) Source(76, 15) + SourceIndex(0)
-6 >Emitted(99, 28) Source(76, 20) + SourceIndex(0)
-7 >Emitted(99, 33) Source(76, 15) + SourceIndex(0)
-8 >Emitted(99, 45) Source(76, 20) + SourceIndex(0)
-9 >Emitted(99, 53) Source(100, 2) + SourceIndex(0)
+1 >Emitted(100, 5) Source(100, 1) + SourceIndex(0)
+2 >Emitted(100, 6) Source(100, 2) + SourceIndex(0)
+3 >Emitted(100, 8) Source(76, 15) + SourceIndex(0)
+4 >Emitted(100, 13) Source(76, 20) + SourceIndex(0)
+5 >Emitted(100, 16) Source(76, 15) + SourceIndex(0)
+6 >Emitted(100, 28) Source(76, 20) + SourceIndex(0)
+7 >Emitted(100, 33) Source(76, 15) + SourceIndex(0)
+8 >Emitted(100, 45) Source(76, 20) + SourceIndex(0)
+9 >Emitted(100, 53) Source(100, 2) + SourceIndex(0)
 ---
 >>>})(Sample || (Sample = {}));
 1 >
@@ -2046,12 +2047,12 @@ sourceFile:recursiveClassReferenceTest.ts
   >                    
   >                    	}
   >                    }
-1 >Emitted(100, 1) Source(100, 1) + SourceIndex(0)
-2 >Emitted(100, 2) Source(100, 2) + SourceIndex(0)
-3 >Emitted(100, 4) Source(76, 8) + SourceIndex(0)
-4 >Emitted(100, 10) Source(76, 14) + SourceIndex(0)
-5 >Emitted(100, 15) Source(76, 8) + SourceIndex(0)
-6 >Emitted(100, 21) Source(76, 14) + SourceIndex(0)
-7 >Emitted(100, 29) Source(100, 2) + SourceIndex(0)
+1 >Emitted(101, 1) Source(100, 1) + SourceIndex(0)
+2 >Emitted(101, 2) Source(100, 2) + SourceIndex(0)
+3 >Emitted(101, 4) Source(76, 8) + SourceIndex(0)
+4 >Emitted(101, 10) Source(76, 14) + SourceIndex(0)
+5 >Emitted(101, 15) Source(76, 8) + SourceIndex(0)
+6 >Emitted(101, 21) Source(76, 14) + SourceIndex(0)
+7 >Emitted(101, 29) Source(100, 2) + SourceIndex(0)
 ---
 >>>//# sourceMappingURL=recursiveClassReferenceTest.js.map
\ No newline at end of file
diff --git a/tests/baselines/reference/recursiveComplicatedClasses.js b/tests/baselines/reference/recursiveComplicatedClasses.js
index a5756024458..ea31184d856 100644
--- a/tests/baselines/reference/recursiveComplicatedClasses.js
+++ b/tests/baselines/reference/recursiveComplicatedClasses.js
@@ -51,21 +51,24 @@ var Symbol = (function () {
 var InferenceSymbol = (function (_super) {
     __extends(InferenceSymbol, _super);
     function InferenceSymbol() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return InferenceSymbol;
 }(Symbol));
 var ParameterSymbol = (function (_super) {
     __extends(ParameterSymbol, _super);
     function ParameterSymbol() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return ParameterSymbol;
 }(InferenceSymbol));
 var TypeSymbol = (function (_super) {
     __extends(TypeSymbol, _super);
     function TypeSymbol() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return TypeSymbol;
 }(InferenceSymbol));
diff --git a/tests/baselines/reference/recursivelySpecializedConstructorDeclaration.js b/tests/baselines/reference/recursivelySpecializedConstructorDeclaration.js
index 92cc2f72cac..72c97c30966 100644
--- a/tests/baselines/reference/recursivelySpecializedConstructorDeclaration.js
+++ b/tests/baselines/reference/recursivelySpecializedConstructorDeclaration.js
@@ -52,7 +52,8 @@ var MsPortal;
                 var ViewModel = (function (_super) {
                     __extends(ViewModel, _super);
                     function ViewModel() {
-                        _super.apply(this, arguments);
+                        var _this = _super.apply(this, arguments) || this;
+                        return _this;
                     }
                     return ViewModel;
                 }(ItemValue));
diff --git a/tests/baselines/reference/reexportClassDefinition.js b/tests/baselines/reference/reexportClassDefinition.js
index a4b68115ac2..95ce777e446 100644
--- a/tests/baselines/reference/reexportClassDefinition.js
+++ b/tests/baselines/reference/reexportClassDefinition.js
@@ -42,7 +42,8 @@ var foo2 = require("./foo2");
 var x = (function (_super) {
     __extends(x, _super);
     function x() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return x;
 }(foo2.x));
diff --git a/tests/baselines/reference/resolvingClassDeclarationWhenInBaseTypeResolution.js b/tests/baselines/reference/resolvingClassDeclarationWhenInBaseTypeResolution.js
index 6e621a18805..d2ec8e168bf 100644
--- a/tests/baselines/reference/resolvingClassDeclarationWhenInBaseTypeResolution.js
+++ b/tests/baselines/reference/resolvingClassDeclarationWhenInBaseTypeResolution.js
@@ -1030,7 +1030,8 @@ var rionegrensis;
     var caniventer = (function (_super) {
         __extends(caniventer, _super);
         function caniventer() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         caniventer.prototype.salomonseni = function () {
             var _this = this;
@@ -1068,7 +1069,8 @@ var rionegrensis;
     var veraecrucis = (function (_super) {
         __extends(veraecrucis, _super);
         function veraecrucis() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         veraecrucis.prototype.naso = function () {
             var _this = this;
@@ -1247,7 +1249,8 @@ var julianae;
     var oralis = (function (_super) {
         __extends(oralis, _super);
         function oralis() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         oralis.prototype.cepapi = function () {
             var _this = this;
@@ -1333,7 +1336,8 @@ var julianae;
     var sumatrana = (function (_super) {
         __extends(sumatrana, _super);
         function sumatrana() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         sumatrana.prototype.wolffsohni = function () {
             var _this = this;
@@ -1533,7 +1537,8 @@ var julianae;
     var durangae = (function (_super) {
         __extends(durangae, _super);
         function durangae() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         durangae.prototype.Californium = function () {
             var _this = this;
@@ -1607,7 +1612,8 @@ var Lanthanum;
     var nitidus = (function (_super) {
         __extends(nitidus, _super);
         function nitidus() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         nitidus.prototype.granatensis = function () {
             var _this = this;
@@ -1675,7 +1681,8 @@ var Lanthanum;
     var megalonyx = (function (_super) {
         __extends(megalonyx, _super);
         function megalonyx() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         megalonyx.prototype.phillipsii = function () {
             var _this = this;
@@ -1824,7 +1831,8 @@ var rendalli;
     var zuluensis = (function (_super) {
         __extends(zuluensis, _super);
         function zuluensis() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         zuluensis.prototype.telfairi = function () {
             var _this = this;
@@ -1982,7 +1990,8 @@ var rendalli;
     var crenulata = (function (_super) {
         __extends(crenulata, _super);
         function crenulata() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         crenulata.prototype.salvanius = function () {
             var _this = this;
@@ -2065,7 +2074,8 @@ var trivirgatus;
     var mixtus = (function (_super) {
         __extends(mixtus, _super);
         function mixtus() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         mixtus.prototype.ochrogaster = function () {
             var _this = this;
@@ -2307,7 +2317,8 @@ var ruatanica;
     var americanus = (function (_super) {
         __extends(americanus, _super);
         function americanus() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         americanus.prototype.nasoloi = function () {
             var _this = this;
@@ -2342,7 +2353,8 @@ var lavali;
     var wilsoni = (function (_super) {
         __extends(wilsoni, _super);
         function wilsoni() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         wilsoni.prototype.setiger = function () {
             var _this = this;
@@ -2434,7 +2446,8 @@ var lavali;
     var otion = (function (_super) {
         __extends(otion, _super);
         function otion() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         otion.prototype.bonaerensis = function () {
             var _this = this;
@@ -2598,7 +2611,8 @@ var lavali;
     var thaeleri = (function (_super) {
         __extends(thaeleri, _super);
         function thaeleri() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         thaeleri.prototype.coromandra = function () {
             var _this = this;
@@ -2654,7 +2668,8 @@ var lavali;
     var lepturus = (function (_super) {
         __extends(lepturus, _super);
         function lepturus() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         lepturus.prototype.ferrumequinum = function () {
             var _this = this;
@@ -2677,7 +2692,8 @@ var dogramacii;
     var robustulus = (function (_super) {
         __extends(robustulus, _super);
         function robustulus() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         robustulus.prototype.fossor = function () {
             var _this = this;
@@ -2892,7 +2908,8 @@ var lutreolus;
     var schlegeli = (function (_super) {
         __extends(schlegeli, _super);
         function schlegeli() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         schlegeli.prototype.mittendorfi = function () {
             var _this = this;
@@ -3119,7 +3136,8 @@ var panglima;
     var amphibius = (function (_super) {
         __extends(amphibius, _super);
         function amphibius() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         amphibius.prototype.bottegi = function () {
             var _this = this;
@@ -3163,7 +3181,8 @@ var panglima;
     var fundatus = (function (_super) {
         __extends(fundatus, _super);
         function fundatus() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         fundatus.prototype.crassulus = function () {
             var _this = this;
@@ -3189,7 +3208,8 @@ var panglima;
     var abidi = (function (_super) {
         __extends(abidi, _super);
         function abidi() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         abidi.prototype.greyii = function () {
             var _this = this;
@@ -3281,7 +3301,8 @@ var minutus;
     var himalayana = (function (_super) {
         __extends(himalayana, _super);
         function himalayana() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         himalayana.prototype.simoni = function () {
             var _this = this;
@@ -3364,7 +3385,8 @@ var caurinus;
     var mahaganus = (function (_super) {
         __extends(mahaganus, _super);
         function mahaganus() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         mahaganus.prototype.martiniquensis = function () {
             var _this = this;
@@ -3438,7 +3460,8 @@ var howi;
     var angulatus = (function (_super) {
         __extends(angulatus, _super);
         function angulatus() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         angulatus.prototype.pennatus = function () {
             var _this = this;
@@ -3521,7 +3544,8 @@ var sagitta;
     var walkeri = (function (_super) {
         __extends(walkeri, _super);
         function walkeri() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         walkeri.prototype.maracajuensis = function () {
             var _this = this;
@@ -3538,7 +3562,8 @@ var minutus;
     var inez = (function (_super) {
         __extends(inez, _super);
         function inez() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         inez.prototype.vexillaris = function () {
             var _this = this;
@@ -3555,7 +3580,8 @@ var macrorhinos;
     var konganensis = (function (_super) {
         __extends(konganensis, _super);
         function konganensis() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return konganensis;
     }(imperfecta.lasiurus));
@@ -3566,7 +3592,8 @@ var panamensis;
     var linulus = (function (_super) {
         __extends(linulus, _super);
         function linulus() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         linulus.prototype.goslingi = function () {
             var _this = this;
@@ -3718,7 +3745,8 @@ var samarensis;
     var pelurus = (function (_super) {
         __extends(pelurus, _super);
         function pelurus() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         pelurus.prototype.Palladium = function () {
             var _this = this;
@@ -3804,7 +3832,8 @@ var samarensis;
     var fuscus = (function (_super) {
         __extends(fuscus, _super);
         function fuscus() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         fuscus.prototype.planifrons = function () {
             var _this = this;
@@ -3965,7 +3994,8 @@ var sagitta;
     var leptoceros = (function (_super) {
         __extends(leptoceros, _super);
         function leptoceros() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         leptoceros.prototype.victus = function () {
             var _this = this;
@@ -4006,7 +4036,8 @@ var daubentonii;
     var nigricans = (function (_super) {
         __extends(nigricans, _super);
         function nigricans() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         nigricans.prototype.woosnami = function () {
             var _this = this;
@@ -4032,7 +4063,8 @@ var argurus;
     var pygmaea = (function (_super) {
         __extends(pygmaea, _super);
         function pygmaea() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         pygmaea.prototype.pajeros = function () {
             var _this = this;
@@ -4061,7 +4093,8 @@ var chrysaeolus;
     var sarasinorum = (function (_super) {
         __extends(sarasinorum, _super);
         function sarasinorum() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         sarasinorum.prototype.belzebul = function () {
             var _this = this;
@@ -4165,7 +4198,8 @@ var argurus;
     var oreas = (function (_super) {
         __extends(oreas, _super);
         function oreas() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         oreas.prototype.salamonis = function () {
             var _this = this;
@@ -4392,7 +4426,8 @@ var provocax;
     var melanoleuca = (function (_super) {
         __extends(melanoleuca, _super);
         function melanoleuca() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         melanoleuca.prototype.Neodymium = function () {
             var _this = this;
@@ -4436,7 +4471,8 @@ var howi;
     var marcanoi = (function (_super) {
         __extends(marcanoi, _super);
         function marcanoi() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         marcanoi.prototype.formosae = function () {
             var _this = this;
@@ -4843,7 +4879,8 @@ var gabriellae;
     var klossii = (function (_super) {
         __extends(klossii, _super);
         function klossii() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return klossii;
     }(imperfecta.lasiurus));
@@ -5046,7 +5083,8 @@ var imperfecta;
     var ciliolabrum = (function (_super) {
         __extends(ciliolabrum, _super);
         function ciliolabrum() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         ciliolabrum.prototype.leschenaultii = function () {
             var _this = this;
@@ -5108,7 +5146,8 @@ var petrophilus;
     var sodyi = (function (_super) {
         __extends(sodyi, _super);
         function sodyi() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         sodyi.prototype.saundersiae = function () {
             var _this = this;
@@ -5173,7 +5212,8 @@ var caurinus;
     var megaphyllus = (function (_super) {
         __extends(megaphyllus, _super);
         function megaphyllus() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         megaphyllus.prototype.montana = function () {
             var _this = this;
@@ -5346,7 +5386,8 @@ var lutreolus;
     var cor = (function (_super) {
         __extends(cor, _super);
         function cor() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         cor.prototype.antinorii = function () {
             var _this = this;
@@ -5438,7 +5479,8 @@ var argurus;
     var germaini = (function (_super) {
         __extends(germaini, _super);
         function germaini() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         germaini.prototype.sharpei = function () {
             var _this = this;
@@ -5536,7 +5578,8 @@ var dammermani;
     var melanops = (function (_super) {
         __extends(melanops, _super);
         function melanops() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         melanops.prototype.blarina = function () {
             var _this = this;
@@ -5625,7 +5668,8 @@ var argurus;
     var peninsulae = (function (_super) {
         __extends(peninsulae, _super);
         function peninsulae() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         peninsulae.prototype.aitkeni = function () {
             var _this = this;
@@ -5771,7 +5815,8 @@ var ruatanica;
     var Praseodymium = (function (_super) {
         __extends(Praseodymium, _super);
         function Praseodymium() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         Praseodymium.prototype.clara = function () {
             var _this = this;
@@ -5860,7 +5905,8 @@ var caurinus;
     var johorensis = (function (_super) {
         __extends(johorensis, _super);
         function johorensis() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         johorensis.prototype.maini = function () {
             var _this = this;
@@ -5988,7 +6034,8 @@ var caurinus;
     var psilurus = (function (_super) {
         __extends(psilurus, _super);
         function psilurus() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         psilurus.prototype.socialis = function () {
             var _this = this;
diff --git a/tests/baselines/reference/returnInConstructor1.js b/tests/baselines/reference/returnInConstructor1.js
index fab0fe8fe09..cd3a9f4c346 100644
--- a/tests/baselines/reference/returnInConstructor1.js
+++ b/tests/baselines/reference/returnInConstructor1.js
@@ -123,7 +123,8 @@ var G = (function () {
 var H = (function (_super) {
     __extends(H, _super);
     function H() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         return new G(); //error
     }
     return H;
@@ -131,7 +132,8 @@ var H = (function (_super) {
 var I = (function (_super) {
     __extends(I, _super);
     function I() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         return new G();
     }
     return I;
diff --git a/tests/baselines/reference/returnStatements.js b/tests/baselines/reference/returnStatements.js
index a543ad3bdda..659eea55689 100644
--- a/tests/baselines/reference/returnStatements.js
+++ b/tests/baselines/reference/returnStatements.js
@@ -48,7 +48,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/scopeCheckExtendedClassInsidePublicMethod2.js b/tests/baselines/reference/scopeCheckExtendedClassInsidePublicMethod2.js
index 3833a5caf7a..02c81245445 100644
--- a/tests/baselines/reference/scopeCheckExtendedClassInsidePublicMethod2.js
+++ b/tests/baselines/reference/scopeCheckExtendedClassInsidePublicMethod2.js
@@ -22,7 +22,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     D.prototype.c = function () {
         v = 1;
diff --git a/tests/baselines/reference/scopeCheckExtendedClassInsideStaticMethod1.js b/tests/baselines/reference/scopeCheckExtendedClassInsideStaticMethod1.js
index d5de584e779..781fd5ac6ee 100644
--- a/tests/baselines/reference/scopeCheckExtendedClassInsideStaticMethod1.js
+++ b/tests/baselines/reference/scopeCheckExtendedClassInsideStaticMethod1.js
@@ -22,7 +22,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     D.c = function () {
         v = 1;
diff --git a/tests/baselines/reference/scopeTests.js b/tests/baselines/reference/scopeTests.js
index 833e84ee5f3..e9394a64c9b 100644
--- a/tests/baselines/reference/scopeTests.js
+++ b/tests/baselines/reference/scopeTests.js
@@ -25,7 +25,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         this.v = 1;
         this.p = 1;
         C.s = 1;
diff --git a/tests/baselines/reference/shadowPrivateMembers.js b/tests/baselines/reference/shadowPrivateMembers.js
index a1474a24777..d7e1b69e274 100644
--- a/tests/baselines/reference/shadowPrivateMembers.js
+++ b/tests/baselines/reference/shadowPrivateMembers.js
@@ -18,7 +18,8 @@ var base = (function () {
 var derived = (function (_super) {
     __extends(derived, _super);
     function derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     derived.prototype.n = function () { };
     return derived;
diff --git a/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js b/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js
index 1d852127963..ea71fbc20c0 100644
--- a/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js
+++ b/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js
@@ -21,7 +21,8 @@ var AbstractGreeter = (function () {
 var Greeter = (function (_super) {
     __extends(Greeter, _super);
     function Greeter() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.a = 10;
         this.nameA = "Ten";
     }
diff --git a/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js.map b/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js.map
index 9c350133f2b..e36f2eaaf8e 100644
--- a/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js.map
+++ b/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js.map
@@ -1,2 +1,2 @@
 //// [sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js.map]
-{"version":3,"file":"sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js","sourceRoot":"","sources":["sourceMapValidationClassWithDefaultConstructorAndExtendsClause.ts"],"names":[],"mappings":";;;;;AAAA;IAAA;IACA,CAAC;IAAD,sBAAC;AAAD,CAAC,AADD,IACC;AAED;IAAsB,2BAAe;IAArC;;QACW,MAAC,GAAG,EAAE,CAAC;QACP,UAAK,GAAG,KAAK,CAAC;IACzB,CAAC;IAAD,cAAC;AAAD,CAAC,AAHD,CAAsB,eAAe,GAGpC"}
\ No newline at end of file
+{"version":3,"file":"sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js","sourceRoot":"","sources":["sourceMapValidationClassWithDefaultConstructorAndExtendsClause.ts"],"names":[],"mappings":";;;;;AAAA;IAAA;IACA,CAAC;IAAD,sBAAC;AAAD,CAAC,AADD,IACC;AAED;IAAsB,2BAAe;IAArC;QAAA,UAGC;;QAFU,MAAC,GAAG,EAAE,CAAC;QACP,UAAK,GAAG,KAAK,CAAC;IACzB,CAAC;IAAD,cAAC;AAAD,CAAC,AAHD,CAAsB,eAAe,GAGpC"}
\ No newline at end of file
diff --git a/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.sourcemap.txt b/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.sourcemap.txt
index f3052384651..3da1d42edcd 100644
--- a/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.sourcemap.txt
+++ b/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.sourcemap.txt
@@ -77,11 +77,23 @@ sourceFile:sourceMapValidationClassWithDefaultConstructorAndExtendsClause.ts
 ---
 >>>    function Greeter() {
 1 >^^^^
-2 >    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
+2 >    ^^^^^^^^^^^^^^^->
 1 >
 1 >Emitted(13, 5) Source(4, 1) + SourceIndex(0)
 ---
->>>        _super.apply(this, arguments);
+>>>        var _this;
+1->^^^^^^^^
+2 >        ^^^^^^^^^^
+3 >                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
+1->
+2 >        class Greeter extends AbstractGreeter {
+  >            public a = 10;
+  >            public nameA = "Ten";
+  >        }
+1->Emitted(14, 9) Source(4, 1) + SourceIndex(0)
+2 >Emitted(14, 19) Source(7, 2) + SourceIndex(0)
+---
+>>>        _this = _super.apply(this, arguments) || this;
 >>>        this.a = 10;
 1->^^^^^^^^
 2 >        ^^^^^^
@@ -89,17 +101,16 @@ sourceFile:sourceMapValidationClassWithDefaultConstructorAndExtendsClause.ts
 4 >                 ^^
 5 >                   ^
 6 >                    ^^^^^^^^->
-1->class Greeter extends AbstractGreeter {
-  >    public 
+1->
 2 >        a
 3 >               = 
 4 >                 10
 5 >                   ;
-1->Emitted(15, 9) Source(5, 12) + SourceIndex(0)
-2 >Emitted(15, 15) Source(5, 13) + SourceIndex(0)
-3 >Emitted(15, 18) Source(5, 16) + SourceIndex(0)
-4 >Emitted(15, 20) Source(5, 18) + SourceIndex(0)
-5 >Emitted(15, 21) Source(5, 19) + SourceIndex(0)
+1->Emitted(16, 9) Source(5, 12) + SourceIndex(0)
+2 >Emitted(16, 15) Source(5, 13) + SourceIndex(0)
+3 >Emitted(16, 18) Source(5, 16) + SourceIndex(0)
+4 >Emitted(16, 20) Source(5, 18) + SourceIndex(0)
+5 >Emitted(16, 21) Source(5, 19) + SourceIndex(0)
 ---
 >>>        this.nameA = "Ten";
 1->^^^^^^^^
@@ -113,11 +124,11 @@ sourceFile:sourceMapValidationClassWithDefaultConstructorAndExtendsClause.ts
 3 >                   = 
 4 >                     "Ten"
 5 >                          ;
-1->Emitted(16, 9) Source(6, 12) + SourceIndex(0)
-2 >Emitted(16, 19) Source(6, 17) + SourceIndex(0)
-3 >Emitted(16, 22) Source(6, 20) + SourceIndex(0)
-4 >Emitted(16, 27) Source(6, 25) + SourceIndex(0)
-5 >Emitted(16, 28) Source(6, 26) + SourceIndex(0)
+1->Emitted(17, 9) Source(6, 12) + SourceIndex(0)
+2 >Emitted(17, 19) Source(6, 17) + SourceIndex(0)
+3 >Emitted(17, 22) Source(6, 20) + SourceIndex(0)
+4 >Emitted(17, 27) Source(6, 25) + SourceIndex(0)
+5 >Emitted(17, 28) Source(6, 26) + SourceIndex(0)
 ---
 >>>    }
 1 >^^^^
@@ -126,8 +137,8 @@ sourceFile:sourceMapValidationClassWithDefaultConstructorAndExtendsClause.ts
 1 >
   >
 2 >    }
-1 >Emitted(17, 5) Source(7, 1) + SourceIndex(0)
-2 >Emitted(17, 6) Source(7, 2) + SourceIndex(0)
+1 >Emitted(18, 5) Source(7, 1) + SourceIndex(0)
+2 >Emitted(18, 6) Source(7, 2) + SourceIndex(0)
 ---
 >>>    return Greeter;
 1->^^^^
@@ -135,8 +146,8 @@ sourceFile:sourceMapValidationClassWithDefaultConstructorAndExtendsClause.ts
 3 >                  ^^^->
 1->
 2 >    }
-1->Emitted(18, 5) Source(7, 1) + SourceIndex(0)
-2 >Emitted(18, 19) Source(7, 2) + SourceIndex(0)
+1->Emitted(19, 5) Source(7, 1) + SourceIndex(0)
+2 >Emitted(19, 19) Source(7, 2) + SourceIndex(0)
 ---
 >>>}(AbstractGreeter));
 1->
@@ -155,11 +166,11 @@ sourceFile:sourceMapValidationClassWithDefaultConstructorAndExtendsClause.ts
   >                     public a = 10;
   >                     public nameA = "Ten";
   >                 }
-1->Emitted(19, 1) Source(7, 1) + SourceIndex(0)
-2 >Emitted(19, 2) Source(7, 2) + SourceIndex(0)
-3 >Emitted(19, 2) Source(4, 1) + SourceIndex(0)
-4 >Emitted(19, 3) Source(4, 23) + SourceIndex(0)
-5 >Emitted(19, 18) Source(4, 38) + SourceIndex(0)
-6 >Emitted(19, 21) Source(7, 2) + SourceIndex(0)
+1->Emitted(20, 1) Source(7, 1) + SourceIndex(0)
+2 >Emitted(20, 2) Source(7, 2) + SourceIndex(0)
+3 >Emitted(20, 2) Source(4, 1) + SourceIndex(0)
+4 >Emitted(20, 3) Source(4, 23) + SourceIndex(0)
+5 >Emitted(20, 18) Source(4, 38) + SourceIndex(0)
+6 >Emitted(20, 21) Source(7, 2) + SourceIndex(0)
 ---
 >>>//# sourceMappingURL=sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js.map
\ No newline at end of file
diff --git a/tests/baselines/reference/specializedInheritedConstructors1.js b/tests/baselines/reference/specializedInheritedConstructors1.js
index f521ba14838..4f14cb6db97 100644
--- a/tests/baselines/reference/specializedInheritedConstructors1.js
+++ b/tests/baselines/reference/specializedInheritedConstructors1.js
@@ -36,7 +36,8 @@ var Model = (function () {
 var MyView = (function (_super) {
     __extends(MyView, _super);
     function MyView() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return MyView;
 }(View));
diff --git a/tests/baselines/reference/specializedOverloadWithRestParameters.js b/tests/baselines/reference/specializedOverloadWithRestParameters.js
index 62688f7cb7e..3b909a80836 100644
--- a/tests/baselines/reference/specializedOverloadWithRestParameters.js
+++ b/tests/baselines/reference/specializedOverloadWithRestParameters.js
@@ -27,7 +27,8 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived1.prototype.bar = function () { };
     return Derived1;
diff --git a/tests/baselines/reference/staticFactory1.js b/tests/baselines/reference/staticFactory1.js
index 6ccd30e37d1..d229c5330ba 100644
--- a/tests/baselines/reference/staticFactory1.js
+++ b/tests/baselines/reference/staticFactory1.js
@@ -31,7 +31,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Derived.prototype.foo = function () { return 2; };
     return Derived;
diff --git a/tests/baselines/reference/staticInheritance.js b/tests/baselines/reference/staticInheritance.js
index 52868930792..8b4b8326cab 100644
--- a/tests/baselines/reference/staticInheritance.js
+++ b/tests/baselines/reference/staticInheritance.js
@@ -27,7 +27,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.p1 = doThing(A); // OK
         this.p2 = doThing(B); // OK
     }
diff --git a/tests/baselines/reference/staticMemberAccessOffDerivedType1.js b/tests/baselines/reference/staticMemberAccessOffDerivedType1.js
index 1c76a251220..a07bea081a9 100644
--- a/tests/baselines/reference/staticMemberAccessOffDerivedType1.js
+++ b/tests/baselines/reference/staticMemberAccessOffDerivedType1.js
@@ -26,7 +26,8 @@ var SomeBase = (function () {
 var P = (function (_super) {
     __extends(P, _super);
     function P() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return P;
 }(SomeBase));
diff --git a/tests/baselines/reference/staticPropSuper.js b/tests/baselines/reference/staticPropSuper.js
index c25c406746d..b2eea36eece 100644
--- a/tests/baselines/reference/staticPropSuper.js
+++ b/tests/baselines/reference/staticPropSuper.js
@@ -49,8 +49,9 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
+        var _this;
         var x = 1; // should not error
-        _super.call(this);
+        _this = _super.call(this) || this;
     }
     return B;
 }(A));
@@ -58,6 +59,7 @@ B.s = 9;
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
+        var _this;
         this.p = 10;
         var x = 1; // should error
     }
@@ -66,6 +68,7 @@ var C = (function (_super) {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
+        var _this;
         this.p = 11;
         var x = 1; // should error
     }
@@ -74,6 +77,7 @@ var D = (function (_super) {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
+        var _this;
         this.p = 12;
         var x = 1; // should error
     }
diff --git a/tests/baselines/reference/strictModeInConstructor.js b/tests/baselines/reference/strictModeInConstructor.js
index 446fed5b76a..e40e0c45a59 100644
--- a/tests/baselines/reference/strictModeInConstructor.js
+++ b/tests/baselines/reference/strictModeInConstructor.js
@@ -74,8 +74,9 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
+        var _this;
         "use strict"; // No error
-        _super.call(this);
+        _this = _super.call(this) || this;
         this.s = 9;
     }
     return B;
@@ -83,7 +84,8 @@ var B = (function (_super) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.call(this); // No error
+        var _this;
+        _this = _super.call(this) || this; // No error
         this.s = 9;
         "use strict";
     }
@@ -92,9 +94,10 @@ var C = (function (_super) {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
+        var _this;
         this.s = 9;
         var x = 1; // Error
-        _super.call(this);
+        _this = _super.call(this) || this;
         "use strict";
     }
     return D;
@@ -102,8 +105,9 @@ var D = (function (_super) {
 var Bs = (function (_super) {
     __extends(Bs, _super);
     function Bs() {
+        var _this;
         "use strict"; // No error
-        _super.call(this);
+        _this = _super.call(this) || this;
     }
     return Bs;
 }(A));
@@ -111,7 +115,8 @@ Bs.s = 9;
 var Cs = (function (_super) {
     __extends(Cs, _super);
     function Cs() {
-        _super.call(this); // No error
+        var _this;
+        _this = _super.call(this) || this; // No error
         "use strict";
     }
     return Cs;
@@ -120,8 +125,9 @@ Cs.s = 9;
 var Ds = (function (_super) {
     __extends(Ds, _super);
     function Ds() {
+        var _this;
         var x = 1; // no Error
-        _super.call(this);
+        _this = _super.call(this) || this;
         "use strict";
     }
     return Ds;
diff --git a/tests/baselines/reference/strictModeReservedWord.js b/tests/baselines/reference/strictModeReservedWord.js
index 210d9ec75be..af01ca1716f 100644
--- a/tests/baselines/reference/strictModeReservedWord.js
+++ b/tests/baselines/reference/strictModeReservedWord.js
@@ -48,7 +48,8 @@ function foo() {
     var myClass = (function (_super) {
         __extends(package, _super);
         function package() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return package;
     }(public));
diff --git a/tests/baselines/reference/strictModeReservedWordInClassDeclaration.js b/tests/baselines/reference/strictModeReservedWordInClassDeclaration.js
index 281b4ade5d6..300d83b9bbc 100644
--- a/tests/baselines/reference/strictModeReservedWordInClassDeclaration.js
+++ b/tests/baselines/reference/strictModeReservedWordInClassDeclaration.js
@@ -75,14 +75,16 @@ var F1 = (function () {
 var G = (function (_super) {
     __extends(G, _super);
     function G() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return G;
 }(package));
 var H = (function (_super) {
     __extends(H, _super);
     function H() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return H;
 }(package.A));
diff --git a/tests/baselines/reference/stringIndexerConstrainsPropertyDeclarations2.js b/tests/baselines/reference/stringIndexerConstrainsPropertyDeclarations2.js
index 08a26230f37..eb5052f51d7 100644
--- a/tests/baselines/reference/stringIndexerConstrainsPropertyDeclarations2.js
+++ b/tests/baselines/reference/stringIndexerConstrainsPropertyDeclarations2.js
@@ -55,7 +55,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     B.prototype.bar = function () { return ''; };
     return B;
diff --git a/tests/baselines/reference/subtypesOfTypeParameter.js b/tests/baselines/reference/subtypesOfTypeParameter.js
index 10d9e3e42ec..cbe42a510b3 100644
--- a/tests/baselines/reference/subtypesOfTypeParameter.js
+++ b/tests/baselines/reference/subtypesOfTypeParameter.js
@@ -120,7 +120,8 @@ var C3 = (function () {
 var D1 = (function (_super) {
     __extends(D1, _super);
     function D1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D1;
 }(C3));
diff --git a/tests/baselines/reference/subtypesOfTypeParameterWithConstraints.js b/tests/baselines/reference/subtypesOfTypeParameterWithConstraints.js
index 0753c52dc9e..56800248393 100644
--- a/tests/baselines/reference/subtypesOfTypeParameterWithConstraints.js
+++ b/tests/baselines/reference/subtypesOfTypeParameterWithConstraints.js
@@ -182,28 +182,32 @@ var C3 = (function () {
 var D1 = (function (_super) {
     __extends(D1, _super);
     function D1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D1;
 }(C3));
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D2;
 }(C3));
 var D3 = (function (_super) {
     __extends(D3, _super);
     function D3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D3;
 }(C3));
 var D4 = (function (_super) {
     __extends(D4, _super);
     function D4() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D4;
 }(C3));
@@ -213,21 +217,24 @@ var D4 = (function (_super) {
 var D5 = (function (_super) {
     __extends(D5, _super);
     function D5() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D5;
 }(C3));
 var D6 = (function (_super) {
     __extends(D6, _super);
     function D6() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D6;
 }(C3));
 var D7 = (function (_super) {
     __extends(D7, _super);
     function D7() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D7;
 }(C3));
@@ -236,21 +243,24 @@ var D7 = (function (_super) {
 var D8 = (function (_super) {
     __extends(D8, _super);
     function D8() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D8;
 }(C3));
 var D9 = (function (_super) {
     __extends(D9, _super);
     function D9() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D9;
 }(C3));
 var D10 = (function (_super) {
     __extends(D10, _super);
     function D10() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D10;
 }(C3));
@@ -259,21 +269,24 @@ var D10 = (function (_super) {
 var D11 = (function (_super) {
     __extends(D11, _super);
     function D11() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D11;
 }(C3));
 var D12 = (function (_super) {
     __extends(D12, _super);
     function D12() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D12;
 }(C3));
 var D13 = (function (_super) {
     __extends(D13, _super);
     function D13() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D13;
 }(C3));
@@ -283,28 +296,32 @@ var D13 = (function (_super) {
 var D14 = (function (_super) {
     __extends(D14, _super);
     function D14() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D14;
 }(C3));
 var D15 = (function (_super) {
     __extends(D15, _super);
     function D15() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D15;
 }(C3));
 var D16 = (function (_super) {
     __extends(D16, _super);
     function D16() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D16;
 }(C3));
 var D17 = (function (_super) {
     __extends(D17, _super);
     function D17() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D17;
 }(C3));
@@ -313,28 +330,32 @@ var D17 = (function (_super) {
 var D18 = (function (_super) {
     __extends(D18, _super);
     function D18() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D18;
 }(C3));
 var D19 = (function (_super) {
     __extends(D19, _super);
     function D19() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D19;
 }(C3));
 var D20 = (function (_super) {
     __extends(D20, _super);
     function D20() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D20;
 }(C3));
 var D21 = (function (_super) {
     __extends(D21, _super);
     function D21() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D21;
 }(C3));
@@ -343,28 +364,32 @@ var D21 = (function (_super) {
 var D22 = (function (_super) {
     __extends(D22, _super);
     function D22() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D22;
 }(C3));
 var D23 = (function (_super) {
     __extends(D23, _super);
     function D23() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D23;
 }(C3));
 var D24 = (function (_super) {
     __extends(D24, _super);
     function D24() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D24;
 }(C3));
 var D25 = (function (_super) {
     __extends(D25, _super);
     function D25() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D25;
 }(C3));
@@ -373,28 +398,32 @@ var D25 = (function (_super) {
 var D26 = (function (_super) {
     __extends(D26, _super);
     function D26() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D26;
 }(C3));
 var D27 = (function (_super) {
     __extends(D27, _super);
     function D27() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D27;
 }(C3));
 var D28 = (function (_super) {
     __extends(D28, _super);
     function D28() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D28;
 }(C3));
 var D29 = (function (_super) {
     __extends(D29, _super);
     function D29() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D29;
 }(C3));
diff --git a/tests/baselines/reference/subtypesOfTypeParameterWithConstraints4.js b/tests/baselines/reference/subtypesOfTypeParameterWithConstraints4.js
index f388bd4e047..e4e35262d80 100644
--- a/tests/baselines/reference/subtypesOfTypeParameterWithConstraints4.js
+++ b/tests/baselines/reference/subtypesOfTypeParameterWithConstraints4.js
@@ -118,63 +118,72 @@ var B1 = (function () {
 var D1 = (function (_super) {
     __extends(D1, _super);
     function D1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D1;
 }(B1));
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D2;
 }(B1));
 var D3 = (function (_super) {
     __extends(D3, _super);
     function D3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D3;
 }(B1));
 var D4 = (function (_super) {
     __extends(D4, _super);
     function D4() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D4;
 }(B1));
 var D5 = (function (_super) {
     __extends(D5, _super);
     function D5() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D5;
 }(B1));
 var D6 = (function (_super) {
     __extends(D6, _super);
     function D6() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D6;
 }(B1));
 var D7 = (function (_super) {
     __extends(D7, _super);
     function D7() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D7;
 }(B1));
 var D8 = (function (_super) {
     __extends(D8, _super);
     function D8() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D8;
 }(B1));
 var D9 = (function (_super) {
     __extends(D9, _super);
     function D9() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D9;
 }(B1));
diff --git a/tests/baselines/reference/subtypesOfTypeParameterWithRecursiveConstraints.js b/tests/baselines/reference/subtypesOfTypeParameterWithRecursiveConstraints.js
index cffda7d7f55..0d1347cd33c 100644
--- a/tests/baselines/reference/subtypesOfTypeParameterWithRecursiveConstraints.js
+++ b/tests/baselines/reference/subtypesOfTypeParameterWithRecursiveConstraints.js
@@ -217,63 +217,72 @@ var M1;
     var D1 = (function (_super) {
         __extends(D1, _super);
         function D1() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D1;
     }(Base));
     var D2 = (function (_super) {
         __extends(D2, _super);
         function D2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D2;
     }(Base));
     var D3 = (function (_super) {
         __extends(D3, _super);
         function D3() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D3;
     }(Base));
     var D4 = (function (_super) {
         __extends(D4, _super);
         function D4() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D4;
     }(Base));
     var D5 = (function (_super) {
         __extends(D5, _super);
         function D5() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D5;
     }(Base));
     var D6 = (function (_super) {
         __extends(D6, _super);
         function D6() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D6;
     }(Base));
     var D7 = (function (_super) {
         __extends(D7, _super);
         function D7() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D7;
     }(Base));
     var D8 = (function (_super) {
         __extends(D8, _super);
         function D8() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D8;
     }(Base));
     var D9 = (function (_super) {
         __extends(D9, _super);
         function D9() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D9;
     }(Base));
@@ -288,63 +297,72 @@ var M2;
     var D1 = (function (_super) {
         __extends(D1, _super);
         function D1() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D1;
     }(Base2));
     var D2 = (function (_super) {
         __extends(D2, _super);
         function D2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D2;
     }(Base2));
     var D3 = (function (_super) {
         __extends(D3, _super);
         function D3() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D3;
     }(Base2));
     var D4 = (function (_super) {
         __extends(D4, _super);
         function D4() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D4;
     }(Base2));
     var D5 = (function (_super) {
         __extends(D5, _super);
         function D5() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D5;
     }(Base2));
     var D6 = (function (_super) {
         __extends(D6, _super);
         function D6() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D6;
     }(Base2));
     var D7 = (function (_super) {
         __extends(D7, _super);
         function D7() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D7;
     }(Base2));
     var D8 = (function (_super) {
         __extends(D8, _super);
         function D8() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D8;
     }(Base2));
     var D9 = (function (_super) {
         __extends(D9, _super);
         function D9() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return D9;
     }(Base2));
diff --git a/tests/baselines/reference/subtypingTransitivity.js b/tests/baselines/reference/subtypingTransitivity.js
index 9d3df207a0c..9ba7ac52df5 100644
--- a/tests/baselines/reference/subtypingTransitivity.js
+++ b/tests/baselines/reference/subtypingTransitivity.js
@@ -33,14 +33,16 @@ var B = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(B));
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D2;
 }(B));
diff --git a/tests/baselines/reference/subtypingWithCallSignatures2.js b/tests/baselines/reference/subtypingWithCallSignatures2.js
index 014ce4a3003..d4cd66a5e0a 100644
--- a/tests/baselines/reference/subtypingWithCallSignatures2.js
+++ b/tests/baselines/reference/subtypingWithCallSignatures2.js
@@ -187,21 +187,24 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/subtypingWithCallSignatures3.js b/tests/baselines/reference/subtypingWithCallSignatures3.js
index 55f5fa60e71..93b1cbebd0a 100644
--- a/tests/baselines/reference/subtypingWithCallSignatures3.js
+++ b/tests/baselines/reference/subtypingWithCallSignatures3.js
@@ -136,21 +136,24 @@ var Errors;
     var Derived = (function (_super) {
         __extends(Derived, _super);
         function Derived() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Derived;
     }(Base));
     var Derived2 = (function (_super) {
         __extends(Derived2, _super);
         function Derived2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Derived2;
     }(Derived));
     var OtherDerived = (function (_super) {
         __extends(OtherDerived, _super);
         function OtherDerived() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return OtherDerived;
     }(Base));
diff --git a/tests/baselines/reference/subtypingWithCallSignatures4.js b/tests/baselines/reference/subtypingWithCallSignatures4.js
index b8839316e86..5cab9f1e7c4 100644
--- a/tests/baselines/reference/subtypingWithCallSignatures4.js
+++ b/tests/baselines/reference/subtypingWithCallSignatures4.js
@@ -126,21 +126,24 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/subtypingWithConstructSignatures2.js b/tests/baselines/reference/subtypingWithConstructSignatures2.js
index c4168febf4e..ec551f5f58c 100644
--- a/tests/baselines/reference/subtypingWithConstructSignatures2.js
+++ b/tests/baselines/reference/subtypingWithConstructSignatures2.js
@@ -187,21 +187,24 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/subtypingWithConstructSignatures3.js b/tests/baselines/reference/subtypingWithConstructSignatures3.js
index 171e52505e0..ba833c31e7a 100644
--- a/tests/baselines/reference/subtypingWithConstructSignatures3.js
+++ b/tests/baselines/reference/subtypingWithConstructSignatures3.js
@@ -138,21 +138,24 @@ var Errors;
     var Derived = (function (_super) {
         __extends(Derived, _super);
         function Derived() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Derived;
     }(Base));
     var Derived2 = (function (_super) {
         __extends(Derived2, _super);
         function Derived2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Derived2;
     }(Derived));
     var OtherDerived = (function (_super) {
         __extends(OtherDerived, _super);
         function OtherDerived() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return OtherDerived;
     }(Base));
diff --git a/tests/baselines/reference/subtypingWithConstructSignatures4.js b/tests/baselines/reference/subtypingWithConstructSignatures4.js
index 1152dde04dd..0b624fcbc51 100644
--- a/tests/baselines/reference/subtypingWithConstructSignatures4.js
+++ b/tests/baselines/reference/subtypingWithConstructSignatures4.js
@@ -126,21 +126,24 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/subtypingWithConstructSignatures5.js b/tests/baselines/reference/subtypingWithConstructSignatures5.js
index 24a5ce77dd0..3d2d4d50d6e 100644
--- a/tests/baselines/reference/subtypingWithConstructSignatures5.js
+++ b/tests/baselines/reference/subtypingWithConstructSignatures5.js
@@ -64,21 +64,24 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/subtypingWithConstructSignatures6.js b/tests/baselines/reference/subtypingWithConstructSignatures6.js
index 8778255dbd5..1cec204ff87 100644
--- a/tests/baselines/reference/subtypingWithConstructSignatures6.js
+++ b/tests/baselines/reference/subtypingWithConstructSignatures6.js
@@ -67,21 +67,24 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/subtypingWithNumericIndexer.js b/tests/baselines/reference/subtypingWithNumericIndexer.js
index cd447c116da..2aa4d834395 100644
--- a/tests/baselines/reference/subtypingWithNumericIndexer.js
+++ b/tests/baselines/reference/subtypingWithNumericIndexer.js
@@ -54,14 +54,16 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
 var B2 = (function (_super) {
     __extends(B2, _super);
     function B2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B2;
 }(A));
@@ -75,28 +77,32 @@ var Generics;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(A));
     var B2 = (function (_super) {
         __extends(B2, _super);
         function B2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B2;
     }(A));
     var B3 = (function (_super) {
         __extends(B3, _super);
         function B3() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B3;
     }(A));
     var B4 = (function (_super) {
         __extends(B4, _super);
         function B4() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B4;
     }(A));
diff --git a/tests/baselines/reference/subtypingWithNumericIndexer3.js b/tests/baselines/reference/subtypingWithNumericIndexer3.js
index 104141b761d..60f463546c8 100644
--- a/tests/baselines/reference/subtypingWithNumericIndexer3.js
+++ b/tests/baselines/reference/subtypingWithNumericIndexer3.js
@@ -58,14 +58,16 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
 var B2 = (function (_super) {
     __extends(B2, _super);
     function B2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B2;
 }(A));
@@ -79,35 +81,40 @@ var Generics;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(A));
     var B2 = (function (_super) {
         __extends(B2, _super);
         function B2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B2;
     }(A));
     var B3 = (function (_super) {
         __extends(B3, _super);
         function B3() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B3;
     }(A));
     var B4 = (function (_super) {
         __extends(B4, _super);
         function B4() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B4;
     }(A));
     var B5 = (function (_super) {
         __extends(B5, _super);
         function B5() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B5;
     }(A));
diff --git a/tests/baselines/reference/subtypingWithNumericIndexer4.js b/tests/baselines/reference/subtypingWithNumericIndexer4.js
index 59f8cd95ad0..f40804bd55f 100644
--- a/tests/baselines/reference/subtypingWithNumericIndexer4.js
+++ b/tests/baselines/reference/subtypingWithNumericIndexer4.js
@@ -42,7 +42,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
@@ -56,14 +57,16 @@ var Generics;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(A));
     var B3 = (function (_super) {
         __extends(B3, _super);
         function B3() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B3;
     }(A));
diff --git a/tests/baselines/reference/subtypingWithObjectMembers.js b/tests/baselines/reference/subtypingWithObjectMembers.js
index c3cef6601e6..420be798293 100644
--- a/tests/baselines/reference/subtypingWithObjectMembers.js
+++ b/tests/baselines/reference/subtypingWithObjectMembers.js
@@ -81,14 +81,16 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Derived));
@@ -102,7 +104,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
@@ -114,7 +117,8 @@ var A2 = (function () {
 var B2 = (function (_super) {
     __extends(B2, _super);
     function B2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B2;
 }(A2));
@@ -126,7 +130,8 @@ var A3 = (function () {
 var B3 = (function (_super) {
     __extends(B3, _super);
     function B3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B3;
 }(A3));
@@ -140,7 +145,8 @@ var TwoLevels;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(A));
@@ -152,7 +158,8 @@ var TwoLevels;
     var B2 = (function (_super) {
         __extends(B2, _super);
         function B2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B2;
     }(A2));
@@ -164,7 +171,8 @@ var TwoLevels;
     var B3 = (function (_super) {
         __extends(B3, _super);
         function B3() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B3;
     }(A3));
diff --git a/tests/baselines/reference/subtypingWithObjectMembers4.js b/tests/baselines/reference/subtypingWithObjectMembers4.js
index d5c1107e45d..0bb50afe985 100644
--- a/tests/baselines/reference/subtypingWithObjectMembers4.js
+++ b/tests/baselines/reference/subtypingWithObjectMembers4.js
@@ -48,7 +48,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
@@ -60,7 +61,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
@@ -72,7 +74,8 @@ var A2 = (function () {
 var B2 = (function (_super) {
     __extends(B2, _super);
     function B2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B2;
 }(A2));
@@ -84,7 +87,8 @@ var A3 = (function () {
 var B3 = (function (_super) {
     __extends(B3, _super);
     function B3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B3;
 }(A3));
diff --git a/tests/baselines/reference/subtypingWithObjectMembersAccessibility.js b/tests/baselines/reference/subtypingWithObjectMembersAccessibility.js
index 25faacad88e..ec3b8382eca 100644
--- a/tests/baselines/reference/subtypingWithObjectMembersAccessibility.js
+++ b/tests/baselines/reference/subtypingWithObjectMembersAccessibility.js
@@ -48,7 +48,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
@@ -60,7 +61,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
@@ -72,7 +74,8 @@ var A2 = (function () {
 var B2 = (function (_super) {
     __extends(B2, _super);
     function B2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B2;
 }(A2));
@@ -84,7 +87,8 @@ var A3 = (function () {
 var B3 = (function (_super) {
     __extends(B3, _super);
     function B3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B3;
 }(A3));
diff --git a/tests/baselines/reference/subtypingWithObjectMembersAccessibility2.js b/tests/baselines/reference/subtypingWithObjectMembersAccessibility2.js
index 7b0398143a2..24f36819ff6 100644
--- a/tests/baselines/reference/subtypingWithObjectMembersAccessibility2.js
+++ b/tests/baselines/reference/subtypingWithObjectMembersAccessibility2.js
@@ -76,7 +76,8 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived;
 }(Base));
@@ -90,7 +91,8 @@ var ExplicitPublic;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(A));
@@ -102,7 +104,8 @@ var ExplicitPublic;
     var B2 = (function (_super) {
         __extends(B2, _super);
         function B2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B2;
     }(A2));
@@ -114,7 +117,8 @@ var ExplicitPublic;
     var B3 = (function (_super) {
         __extends(B3, _super);
         function B3() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B3;
     }(A3));
@@ -129,7 +133,8 @@ var ImplicitPublic;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(A));
@@ -141,7 +146,8 @@ var ImplicitPublic;
     var B2 = (function (_super) {
         __extends(B2, _super);
         function B2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B2;
     }(A2));
@@ -153,7 +159,8 @@ var ImplicitPublic;
     var B3 = (function (_super) {
         __extends(B3, _super);
         function B3() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B3;
     }(A3));
diff --git a/tests/baselines/reference/subtypingWithStringIndexer.js b/tests/baselines/reference/subtypingWithStringIndexer.js
index 0740743a5d9..95a71a018d1 100644
--- a/tests/baselines/reference/subtypingWithStringIndexer.js
+++ b/tests/baselines/reference/subtypingWithStringIndexer.js
@@ -55,14 +55,16 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
 var B2 = (function (_super) {
     __extends(B2, _super);
     function B2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B2;
 }(A));
@@ -76,28 +78,32 @@ var Generics;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(A));
     var B2 = (function (_super) {
         __extends(B2, _super);
         function B2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B2;
     }(A));
     var B3 = (function (_super) {
         __extends(B3, _super);
         function B3() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B3;
     }(A));
     var B4 = (function (_super) {
         __extends(B4, _super);
         function B4() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B4;
     }(A));
diff --git a/tests/baselines/reference/subtypingWithStringIndexer3.js b/tests/baselines/reference/subtypingWithStringIndexer3.js
index 5ed44177d52..fd9b400cb3d 100644
--- a/tests/baselines/reference/subtypingWithStringIndexer3.js
+++ b/tests/baselines/reference/subtypingWithStringIndexer3.js
@@ -58,14 +58,16 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
 var B2 = (function (_super) {
     __extends(B2, _super);
     function B2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B2;
 }(A));
@@ -79,35 +81,40 @@ var Generics;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(A));
     var B2 = (function (_super) {
         __extends(B2, _super);
         function B2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B2;
     }(A));
     var B3 = (function (_super) {
         __extends(B3, _super);
         function B3() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B3;
     }(A));
     var B4 = (function (_super) {
         __extends(B4, _super);
         function B4() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B4;
     }(A));
     var B5 = (function (_super) {
         __extends(B5, _super);
         function B5() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B5;
     }(A));
diff --git a/tests/baselines/reference/subtypingWithStringIndexer4.js b/tests/baselines/reference/subtypingWithStringIndexer4.js
index d6fb874c090..46178d1dc32 100644
--- a/tests/baselines/reference/subtypingWithStringIndexer4.js
+++ b/tests/baselines/reference/subtypingWithStringIndexer4.js
@@ -42,7 +42,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return B;
 }(A));
@@ -56,14 +57,16 @@ var Generics;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(A));
     var B3 = (function (_super) {
         __extends(B3, _super);
         function B3() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B3;
     }(A));
diff --git a/tests/baselines/reference/super.js b/tests/baselines/reference/super.js
index 81d76aec62b..54afddcc119 100644
--- a/tests/baselines/reference/super.js
+++ b/tests/baselines/reference/super.js
@@ -58,7 +58,8 @@ var Base = (function () {
 var Sub1 = (function (_super) {
     __extends(Sub1, _super);
     function Sub1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Sub1.prototype.foo = function () {
         return "sub1" + _super.prototype.foo.call(this) + _super.prototype.bar.call(this);
@@ -68,7 +69,8 @@ var Sub1 = (function (_super) {
 var SubSub1 = (function (_super) {
     __extends(SubSub1, _super);
     function SubSub1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     SubSub1.prototype.foo = function () {
         return "subsub1" + _super.prototype.foo.call(this);
diff --git a/tests/baselines/reference/super1.js b/tests/baselines/reference/super1.js
index 4179843b79a..8ef621cdf2b 100644
--- a/tests/baselines/reference/super1.js
+++ b/tests/baselines/reference/super1.js
@@ -84,7 +84,8 @@ var Base1 = (function () {
 var Sub1 = (function (_super) {
     __extends(Sub1, _super);
     function Sub1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Sub1.prototype.bar = function () {
         return "base";
@@ -94,7 +95,8 @@ var Sub1 = (function (_super) {
 var SubSub1 = (function (_super) {
     __extends(SubSub1, _super);
     function SubSub1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     SubSub1.prototype.bar = function () {
         return _super.prototype.super.foo;
@@ -113,7 +115,8 @@ var Base2 = (function () {
 var SubE2 = (function (_super) {
     __extends(SubE2, _super);
     function SubE2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     SubE2.prototype.bar = function () {
         return _super.prototype.prototype.foo = null;
@@ -132,7 +135,8 @@ var Base3 = (function () {
 var SubE3 = (function (_super) {
     __extends(SubE3, _super);
     function SubE3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     SubE3.prototype.bar = function () {
         return _super.prototype.bar.call(this);
@@ -153,7 +157,8 @@ var Base4;
     var SubSub4 = (function (_super) {
         __extends(SubSub4, _super);
         function SubSub4() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         SubSub4.prototype.x = function () {
             return _super.prototype.x.call(this);
diff --git a/tests/baselines/reference/super2.js b/tests/baselines/reference/super2.js
index 979bdba84e4..80e26c36f7c 100644
--- a/tests/baselines/reference/super2.js
+++ b/tests/baselines/reference/super2.js
@@ -71,7 +71,8 @@ var Base5 = (function () {
 var Sub5 = (function (_super) {
     __extends(Sub5, _super);
     function Sub5() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Sub5.prototype.x = function () {
         return "SubX";
@@ -81,7 +82,8 @@ var Sub5 = (function (_super) {
 var SubSub5 = (function (_super) {
     __extends(SubSub5, _super);
     function SubSub5() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     SubSub5.prototype.x = function () {
         return _super.prototype.x.call(this);
@@ -103,7 +105,8 @@ var Base6 = (function () {
 var Sub6 = (function (_super) {
     __extends(Sub6, _super);
     function Sub6() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Sub6.prototype.y = function () {
         return "SubY";
@@ -113,7 +116,8 @@ var Sub6 = (function (_super) {
 var SubSub6 = (function (_super) {
     __extends(SubSub6, _super);
     function SubSub6() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     SubSub6.prototype.y = function () {
         return _super.prototype.y.call(this);
diff --git a/tests/baselines/reference/superAccess.js b/tests/baselines/reference/superAccess.js
index 6e5cd9aca44..8c9d93f3a36 100644
--- a/tests/baselines/reference/superAccess.js
+++ b/tests/baselines/reference/superAccess.js
@@ -30,7 +30,8 @@ MyBase.S1 = 5;
 var MyDerived = (function (_super) {
     __extends(MyDerived, _super);
     function MyDerived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     MyDerived.prototype.foo = function () {
         var l3 = _super.prototype.S1; // Expected => Error: Only public instance methods of the base class are accessible via the 'super' keyword
diff --git a/tests/baselines/reference/superAccess2.js b/tests/baselines/reference/superAccess2.js
index 8de13b5ef51..ff711ca8d75 100644
--- a/tests/baselines/reference/superAccess2.js
+++ b/tests/baselines/reference/superAccess2.js
@@ -41,11 +41,11 @@ var Q = (function (_super) {
     __extends(Q, _super);
     // Super is not allowed in constructor args
     function Q(z, zz, zzz) {
-        var _this = this;
+        var _this;
         if (z === void 0) { z = _super.; }
         if (zz === void 0) { zz = _super.; }
         if (zzz === void 0) { zzz = function () { return _super.; }; }
-        _super.call(this);
+        _this = _super.call(this) || this;
         this.z = z;
         this.xx = _super.prototype.;
     }
diff --git a/tests/baselines/reference/superAccessInFatArrow1.js b/tests/baselines/reference/superAccessInFatArrow1.js
index 3cd4e199c62..be97707b12a 100644
--- a/tests/baselines/reference/superAccessInFatArrow1.js
+++ b/tests/baselines/reference/superAccessInFatArrow1.js
@@ -34,7 +34,8 @@ var test;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         B.prototype.bar = function (callback) {
         };
diff --git a/tests/baselines/reference/superCallArgsMustMatch.js b/tests/baselines/reference/superCallArgsMustMatch.js
index 9dcdbda8e31..3dec9369dd4 100644
--- a/tests/baselines/reference/superCallArgsMustMatch.js
+++ b/tests/baselines/reference/superCallArgsMustMatch.js
@@ -40,9 +40,10 @@ var T5 = (function () {
 var T6 = (function (_super) {
     __extends(T6, _super);
     function T6() {
+        var _this;
         // Should error; base constructor has type T for first arg,
         // which is instantiated with 'number' in the extends clause
-        _super.call(this, "hi");
+        _this = _super.call(this, "hi") || this;
         var x = this.foo;
     }
     return T6;
diff --git a/tests/baselines/reference/superCallAssignResult.js b/tests/baselines/reference/superCallAssignResult.js
index 7002f94eb7d..4eeabdfa282 100644
--- a/tests/baselines/reference/superCallAssignResult.js
+++ b/tests/baselines/reference/superCallAssignResult.js
@@ -24,7 +24,8 @@ var E = (function () {
 var H = (function (_super) {
     __extends(H, _super);
     function H() {
-        var x = _super.call(this, 5); // Should be of type void, not E.
+        var _this;
+        var x = _this = _super.call(this, 5) || this; // Should be of type void, not E.
         x = 5;
     }
     return H;
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing1.js b/tests/baselines/reference/superCallBeforeThisAccessing1.js
index 1fc7ab39c91..e70dde9fd8e 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing1.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing1.js
@@ -30,7 +30,8 @@ var Base = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.call(this, i);
+        var _this;
+        _this = _super.call(this, i) || this;
         var s = {
             t: this._t
         };
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing2.js b/tests/baselines/reference/superCallBeforeThisAccessing2.js
index e5acf06bbfd..8ab6c5f349c 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing2.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing2.js
@@ -24,8 +24,8 @@ var Base = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = this;
-        _super.call(this, function () { _this._t; }); // no error. only check when this is directly accessing in constructor
+        var _this;
+        _this = _super.call(this, function () { _this._t; }) || this; // no error. only check when this is directly accessing in constructor
     }
     return D;
 }(Base));
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing3.js b/tests/baselines/reference/superCallBeforeThisAccessing3.js
index 101d74e4bc7..1f4c8114913 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing3.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing3.js
@@ -27,11 +27,11 @@ var Base = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = this;
+        var _this;
         var x = function () { _this._t; };
         x(); // no error; we only check super is called before this when the container is a constructor
         this._t; // error
-        _super.call(this, undefined);
+        _this = _super.call(this, undefined) || this;
     }
     return D;
 }(Base));
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing4.js b/tests/baselines/reference/superCallBeforeThisAccessing4.js
index 9c3c5ab60c4..2645eaa9795 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing4.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing4.js
@@ -24,15 +24,17 @@ var __extends = (this && this.__extends) || function (d, b) {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
+        var _this;
         this._t;
-        _super.call(this);
+        _this = _super.call(this) || this;
     }
     return D;
 }(null));
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         this._t;
     }
     return E;
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing5.js b/tests/baselines/reference/superCallBeforeThisAccessing5.js
index 3281a3f8b55..df345ec5c26 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing5.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing5.js
@@ -16,6 +16,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
+        var _this;
         this._t; // No error
     }
     return D;
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing6.js b/tests/baselines/reference/superCallBeforeThisAccessing6.js
index 746ce9f2791..d4e8c979552 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing6.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing6.js
@@ -24,7 +24,8 @@ var Base = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.call(this, this);
+        var _this;
+        _this = _super.call(this, this) || this;
     }
     return D;
 }(Base));
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing7.js b/tests/baselines/reference/superCallBeforeThisAccessing7.js
index c3aa1655cf7..f6c41b144eb 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing7.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing7.js
@@ -27,10 +27,11 @@ var Base = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
+        var _this;
         var x = {
             j: this._t
         };
-        _super.call(this, undefined);
+        _this = _super.call(this, undefined) || this;
     }
     return D;
 }(Base));
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing8.js b/tests/baselines/reference/superCallBeforeThisAccessing8.js
index 0865c4305a5..7d09351621a 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing8.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing8.js
@@ -27,8 +27,9 @@ var Base = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
+        var _this;
         var x = {
-            k: _super.call(this, undefined),
+            k: _this = _super.call(this, undefined) || this,
             j: this._t
         };
     }
diff --git a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType1.js b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType1.js
index 50830480b1a..6de41cb5188 100644
--- a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType1.js
+++ b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType1.js
@@ -20,7 +20,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
     }
     return D;
 }(B));
diff --git a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType2.js b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType2.js
index ef770985888..5ae8f8b3874 100644
--- a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType2.js
+++ b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType2.js
@@ -19,7 +19,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
     }
     return D;
 }(B));
diff --git a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithIncorrectNumberOfTypeArguments1.js b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithIncorrectNumberOfTypeArguments1.js
index ebb70023b53..bc85d74c4c8 100644
--- a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithIncorrectNumberOfTypeArguments1.js
+++ b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithIncorrectNumberOfTypeArguments1.js
@@ -25,7 +25,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.call(this, function (value) { return String(value); });
+        var _this;
+        _this = _super.call(this, function (value) { return String(value); }) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithNoTypeArguments1.js b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithNoTypeArguments1.js
index d619343ba14..a1736bb45f0 100644
--- a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithNoTypeArguments1.js
+++ b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithNoTypeArguments1.js
@@ -25,7 +25,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.call(this, function (value) { return String(value); });
+        var _this;
+        _this = _super.call(this, function (value) { return String(value); }) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/superCallFromClassThatDerivesNonGenericTypeButWithTypeArguments1.js b/tests/baselines/reference/superCallFromClassThatDerivesNonGenericTypeButWithTypeArguments1.js
index e9ee84be152..c5beb5df5b5 100644
--- a/tests/baselines/reference/superCallFromClassThatDerivesNonGenericTypeButWithTypeArguments1.js
+++ b/tests/baselines/reference/superCallFromClassThatDerivesNonGenericTypeButWithTypeArguments1.js
@@ -25,7 +25,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.call(this, function (value) { return String(value); });
+        var _this;
+        _this = _super.call(this, function (value) { return String(value); }) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/superCallFromClassThatHasNoBaseType1.js b/tests/baselines/reference/superCallFromClassThatHasNoBaseType1.js
index d793e9bb2ae..e4b358c9a0a 100644
--- a/tests/baselines/reference/superCallFromClassThatHasNoBaseType1.js
+++ b/tests/baselines/reference/superCallFromClassThatHasNoBaseType1.js
@@ -19,7 +19,7 @@ var A = (function () {
 }());
 var B = (function () {
     function B() {
-        _super.call(this, function (value) { return String(value); });
+        _this = _super.call(this, function (value) { return String(value); }) || this;
     }
     return B;
 }());
diff --git a/tests/baselines/reference/superCallFromFunction1.js b/tests/baselines/reference/superCallFromFunction1.js
index a7fcbaaeff0..7f34628c58a 100644
--- a/tests/baselines/reference/superCallFromFunction1.js
+++ b/tests/baselines/reference/superCallFromFunction1.js
@@ -6,5 +6,5 @@ function foo() {
 
 //// [superCallFromFunction1.js]
 function foo() {
-    _super.call(this, function (value) { return String(value); });
+    _this = _super.call(this, function (value) { return String(value); }) || this;
 }
diff --git a/tests/baselines/reference/superCallInConstructorWithNoBaseType.js b/tests/baselines/reference/superCallInConstructorWithNoBaseType.js
index 9746ab6a9de..dcbebeaa452 100644
--- a/tests/baselines/reference/superCallInConstructorWithNoBaseType.js
+++ b/tests/baselines/reference/superCallInConstructorWithNoBaseType.js
@@ -14,13 +14,13 @@ class D<T> {
 //// [superCallInConstructorWithNoBaseType.js]
 var C = (function () {
     function C() {
-        _super.call(this); // error
+        _this = _super.call(this) || this; // error
     }
     return C;
 }());
 var D = (function () {
     function D(x) {
-        _super.call(this); // error
+        _this = _super.call(this) || this; // error
         this.x = x;
     }
     return D;
diff --git a/tests/baselines/reference/superCallInNonStaticMethod.js b/tests/baselines/reference/superCallInNonStaticMethod.js
index 3ff07edf4c9..6640a32be5a 100644
--- a/tests/baselines/reference/superCallInNonStaticMethod.js
+++ b/tests/baselines/reference/superCallInNonStaticMethod.js
@@ -66,8 +66,8 @@ var Doing = (function () {
 var Other = (function (_super) {
     __extends(Other, _super);
     function Other() {
-        var _this = this;
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         this.propertyInitializer = _super.prototype.instanceMethod.call(this);
         this.functionProperty = function () { _super.prototype.instanceMethod.call(_this); };
         _super.prototype.instanceMethod.call(this);
diff --git a/tests/baselines/reference/superCallInStaticMethod.js b/tests/baselines/reference/superCallInStaticMethod.js
index 91558e47d3f..6cf9f79e7a4 100644
--- a/tests/baselines/reference/superCallInStaticMethod.js
+++ b/tests/baselines/reference/superCallInStaticMethod.js
@@ -62,7 +62,8 @@ var Doing = (function () {
 var Other = (function (_super) {
     __extends(Other, _super);
     function Other() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     // in static method
     Other.staticMethod = function () {
diff --git a/tests/baselines/reference/superCallInsideClassDeclaration.js b/tests/baselines/reference/superCallInsideClassDeclaration.js
index e677c426e02..f47b50d4915 100644
--- a/tests/baselines/reference/superCallInsideClassDeclaration.js
+++ b/tests/baselines/reference/superCallInsideClassDeclaration.js
@@ -35,10 +35,12 @@ var C = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
+        var _this;
         var D = (function (_super) {
             __extends(D, _super);
             function D() {
-                _super.call(this);
+                var _this;
+                _this = _super.call(this) || this;
             }
             return D;
         }(C));
diff --git a/tests/baselines/reference/superCallInsideClassExpression.js b/tests/baselines/reference/superCallInsideClassExpression.js
index ee373f69f46..b9e1f6c9786 100644
--- a/tests/baselines/reference/superCallInsideClassExpression.js
+++ b/tests/baselines/reference/superCallInsideClassExpression.js
@@ -35,10 +35,12 @@ var C = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
+        var _this;
         var D = (function (_super) {
             __extends(class_1, _super);
             function class_1() {
-                _super.call(this);
+                var _this;
+                _this = _super.call(this) || this;
             }
             return class_1;
         }(C));
diff --git a/tests/baselines/reference/superCallInsideObjectLiteralExpression.js b/tests/baselines/reference/superCallInsideObjectLiteralExpression.js
index 3f9a0a9ce9c..68a9c19e819 100644
--- a/tests/baselines/reference/superCallInsideObjectLiteralExpression.js
+++ b/tests/baselines/reference/superCallInsideObjectLiteralExpression.js
@@ -28,8 +28,9 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
+        var _this;
         var x = {
-            x: _super.call(this)
+            x: _this = _super.call(this) || this
         };
     }
     return B;
diff --git a/tests/baselines/reference/superCallOutsideConstructor.js b/tests/baselines/reference/superCallOutsideConstructor.js
index 202ed531a10..fd91de4cc8e 100644
--- a/tests/baselines/reference/superCallOutsideConstructor.js
+++ b/tests/baselines/reference/superCallOutsideConstructor.js
@@ -37,13 +37,14 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.call(this);
-        this.x = _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
+        this.x = _this = _super.call(this) || this;
         var y = function () {
-            _super.call(this);
+            _this = _super.call(_this) || _this;
         };
         var y2 = function () {
-            _super.call(this);
+            _this = _super.call(this) || this;
         };
     }
     return D;
diff --git a/tests/baselines/reference/superCallParameterContextualTyping1.js b/tests/baselines/reference/superCallParameterContextualTyping1.js
index 5bfe3927a51..a311ce95fc7 100644
--- a/tests/baselines/reference/superCallParameterContextualTyping1.js
+++ b/tests/baselines/reference/superCallParameterContextualTyping1.js
@@ -28,7 +28,8 @@ var B = (function (_super) {
     __extends(B, _super);
     // Ensure 'value' is of type 'number (and not '{}') by using its 'toExponential()' method.
     function B() {
-        _super.call(this, function (value) { return String(value.toExponential()); });
+        var _this;
+        _this = _super.call(this, function (value) { return String(value.toExponential()); }) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/superCallParameterContextualTyping2.js b/tests/baselines/reference/superCallParameterContextualTyping2.js
index 539ecbed065..9439871f38c 100644
--- a/tests/baselines/reference/superCallParameterContextualTyping2.js
+++ b/tests/baselines/reference/superCallParameterContextualTyping2.js
@@ -27,7 +27,8 @@ var C = (function (_super) {
     __extends(C, _super);
     // Ensure 'value' is not of type 'any' by invoking it with type arguments.
     function C() {
-        _super.call(this, function (value) { return String(value()); });
+        var _this;
+        _this = _super.call(this, function (value) { return String(value()); }) || this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/superCallParameterContextualTyping3.js b/tests/baselines/reference/superCallParameterContextualTyping3.js
index d35a1707bb7..cfa3fd1c074 100644
--- a/tests/baselines/reference/superCallParameterContextualTyping3.js
+++ b/tests/baselines/reference/superCallParameterContextualTyping3.js
@@ -47,13 +47,14 @@ var CBase = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
+        var _this;
         // Should be okay.
         // 'p' should have type 'string'.
-        _super.call(this, {
+        _this = _super.call(this, {
             method: function (p) {
                 p.length;
             }
-        });
+        }) || this;
         // Should be okay.
         // 'p' should have type 'string'.
         _super.prototype.foo.call(this, {
diff --git a/tests/baselines/reference/superCallWithMissingBaseClass.js b/tests/baselines/reference/superCallWithMissingBaseClass.js
index 7758bcfd89d..561b7300fe4 100644
--- a/tests/baselines/reference/superCallWithMissingBaseClass.js
+++ b/tests/baselines/reference/superCallWithMissingBaseClass.js
@@ -18,7 +18,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Foo.prototype.m1 = function () {
         return _super.prototype.m1.call(this);
diff --git a/tests/baselines/reference/superCalls.js b/tests/baselines/reference/superCalls.js
index ae8327ec200..96b0061f47e 100644
--- a/tests/baselines/reference/superCalls.js
+++ b/tests/baselines/reference/superCalls.js
@@ -47,10 +47,11 @@ var Derived = (function (_super) {
     __extends(Derived, _super);
     //super call in class constructor of derived type
     function Derived(q) {
-        _super.call(this, '');
+        var _this;
+        _this = _super.call(this, '') || this;
         this.q = q;
         //type of super call expression is void
-        var p = _super.call(this, '');
+        var p = _this = _super.call(this, '') || this;
         var p = v();
     }
     return Derived;
@@ -63,8 +64,9 @@ var OtherBase = (function () {
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
+        var _this;
         var p = '';
-        _super.call(this);
+        _this = _super.call(this) || this;
     }
     return OtherDerived;
 }(OtherBase));
diff --git a/tests/baselines/reference/superCallsInConstructor.js b/tests/baselines/reference/superCallsInConstructor.js
index 434f730c76b..be34657a0c1 100644
--- a/tests/baselines/reference/superCallsInConstructor.js
+++ b/tests/baselines/reference/superCallsInConstructor.js
@@ -41,14 +41,15 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
+        var _this;
         with (new C()) {
             foo();
-            _super.call(this);
+            _this = _super.call(this) || this;
             bar();
         }
         try { }
         catch (e) {
-            _super.call(this);
+            _this = _super.call(this) || this;
         }
     }
     return Derived;
diff --git a/tests/baselines/reference/superErrors.js b/tests/baselines/reference/superErrors.js
index fd70114d0fd..f962876a391 100644
--- a/tests/baselines/reference/superErrors.js
+++ b/tests/baselines/reference/superErrors.js
@@ -76,7 +76,8 @@ var User = (function () {
 var RegisteredUser = (function (_super) {
     __extends(RegisteredUser, _super);
     function RegisteredUser() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         this.name = "Frank";
         // super call in an inner function in a constructor
         function inner() {
diff --git a/tests/baselines/reference/superInCatchBlock1.js b/tests/baselines/reference/superInCatchBlock1.js
index 9d5cb1affdc..9eb7df62c1a 100644
--- a/tests/baselines/reference/superInCatchBlock1.js
+++ b/tests/baselines/reference/superInCatchBlock1.js
@@ -28,7 +28,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     B.prototype.m = function () {
         try {
diff --git a/tests/baselines/reference/superInConstructorParam1.js b/tests/baselines/reference/superInConstructorParam1.js
index 3c6eb0bdad2..ab1744929a9 100644
--- a/tests/baselines/reference/superInConstructorParam1.js
+++ b/tests/baselines/reference/superInConstructorParam1.js
@@ -27,6 +27,7 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C(a) {
+        var _this;
         if (a === void 0) { a = _super.foo.call(this); }
     }
     return C;
diff --git a/tests/baselines/reference/superInLambdas.js b/tests/baselines/reference/superInLambdas.js
index b0940b1d538..f2c84cb7e64 100644
--- a/tests/baselines/reference/superInLambdas.js
+++ b/tests/baselines/reference/superInLambdas.js
@@ -85,8 +85,8 @@ var User = (function () {
 var RegisteredUser = (function (_super) {
     __extends(RegisteredUser, _super);
     function RegisteredUser() {
-        var _this = this;
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         this.name = "Frank";
         // super call in a constructor
         _super.prototype.sayHello.call(this);
@@ -105,8 +105,8 @@ var RegisteredUser = (function (_super) {
 var RegisteredUser2 = (function (_super) {
     __extends(RegisteredUser2, _super);
     function RegisteredUser2() {
-        var _this = this;
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         this.name = "Joe";
         // super call in a nested lambda in a constructor 
         var x = function () { return function () { return function () { return _super.prototype.sayHello.call(_this); }; }; };
@@ -121,8 +121,8 @@ var RegisteredUser2 = (function (_super) {
 var RegisteredUser3 = (function (_super) {
     __extends(RegisteredUser3, _super);
     function RegisteredUser3() {
-        var _this = this;
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         this.name = "Sam";
         // super property in a nested lambda in a constructor 
         var superName = function () { return function () { return function () { return _super.prototype.name; }; }; };
@@ -137,8 +137,8 @@ var RegisteredUser3 = (function (_super) {
 var RegisteredUser4 = (function (_super) {
     __extends(RegisteredUser4, _super);
     function RegisteredUser4() {
-        var _this = this;
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         this.name = "Mark";
         // super in a nested lambda in a constructor 
         var x = function () { return function () { return _super.prototype.; }; };
diff --git a/tests/baselines/reference/superInObjectLiterals_ES5.js b/tests/baselines/reference/superInObjectLiterals_ES5.js
index 5d1fed24b4f..adeda5835cb 100644
--- a/tests/baselines/reference/superInObjectLiterals_ES5.js
+++ b/tests/baselines/reference/superInObjectLiterals_ES5.js
@@ -100,7 +100,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     B.prototype.f = function () {
         var _this = this;
diff --git a/tests/baselines/reference/superNewCall1.js b/tests/baselines/reference/superNewCall1.js
index 01ae169b598..32c4da4d4e4 100644
--- a/tests/baselines/reference/superNewCall1.js
+++ b/tests/baselines/reference/superNewCall1.js
@@ -27,6 +27,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
+        var _this;
         new _super.prototype(function (value) { return String(value); });
     }
     return B;
diff --git a/tests/baselines/reference/superPropertyAccess.js b/tests/baselines/reference/superPropertyAccess.js
index 0e1e8783448..b1377eb9cde 100644
--- a/tests/baselines/reference/superPropertyAccess.js
+++ b/tests/baselines/reference/superPropertyAccess.js
@@ -61,7 +61,8 @@ var MyBase = (function () {
 var MyDerived = (function (_super) {
     __extends(MyDerived, _super);
     function MyDerived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     MyDerived.prototype.foo = function () {
         _super.prototype.m1.call(this, "hi"); // Should be allowed, method on base prototype
diff --git a/tests/baselines/reference/superPropertyAccess1.js b/tests/baselines/reference/superPropertyAccess1.js
index 4df9398024c..86f059a2fb2 100644
--- a/tests/baselines/reference/superPropertyAccess1.js
+++ b/tests/baselines/reference/superPropertyAccess1.js
@@ -50,7 +50,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         _super.prototype.bar.call(this);
         _super.prototype.x; // error
     }
diff --git a/tests/baselines/reference/superPropertyAccess2.js b/tests/baselines/reference/superPropertyAccess2.js
index ec74a2ea069..be0c44b4081 100644
--- a/tests/baselines/reference/superPropertyAccess2.js
+++ b/tests/baselines/reference/superPropertyAccess2.js
@@ -50,7 +50,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         _super.prototype.bar.call(this); // error
         _super.prototype.x; // error
     }
diff --git a/tests/baselines/reference/superPropertyAccessInComputedPropertiesOfNestedType_ES5.js b/tests/baselines/reference/superPropertyAccessInComputedPropertiesOfNestedType_ES5.js
index a91dfc76e3d..1397a0748ae 100644
--- a/tests/baselines/reference/superPropertyAccessInComputedPropertiesOfNestedType_ES5.js
+++ b/tests/baselines/reference/superPropertyAccessInComputedPropertiesOfNestedType_ES5.js
@@ -29,7 +29,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     B.prototype.foo = function () { return 2; };
     B.prototype.bar = function () {
diff --git a/tests/baselines/reference/superPropertyAccessNoError.js b/tests/baselines/reference/superPropertyAccessNoError.js
index df230ce3703..f7663eab6e0 100644
--- a/tests/baselines/reference/superPropertyAccessNoError.js
+++ b/tests/baselines/reference/superPropertyAccessNoError.js
@@ -99,7 +99,8 @@ var SomeBaseClass = (function () {
 var SomeDerivedClass = (function (_super) {
     __extends(SomeDerivedClass, _super);
     function SomeDerivedClass() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         var x = _super.prototype.func.call(this);
         var x;
     }
diff --git a/tests/baselines/reference/superPropertyAccess_ES5.js b/tests/baselines/reference/superPropertyAccess_ES5.js
index 63f5f6f316a..14492c2788a 100644
--- a/tests/baselines/reference/superPropertyAccess_ES5.js
+++ b/tests/baselines/reference/superPropertyAccess_ES5.js
@@ -49,7 +49,8 @@ var MyBase = (function () {
 var MyDerived = (function (_super) {
     __extends(MyDerived, _super);
     function MyDerived() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
         var f1 = _super.prototype.getValue.call(this);
         var f2 = _super.prototype.value;
     }
@@ -71,7 +72,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Object.defineProperty(B.prototype, "property", {
         set: function (value) {
diff --git a/tests/baselines/reference/superSymbolIndexedAccess5.js b/tests/baselines/reference/superSymbolIndexedAccess5.js
index 3acd26d2974..0796c912d8c 100644
--- a/tests/baselines/reference/superSymbolIndexedAccess5.js
+++ b/tests/baselines/reference/superSymbolIndexedAccess5.js
@@ -31,7 +31,8 @@ var Foo = (function () {
 var Bar = (function (_super) {
     __extends(Bar, _super);
     function Bar() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Bar.prototype[symbol] = function () {
         return _super.prototype[symbol].call(this);
diff --git a/tests/baselines/reference/superSymbolIndexedAccess6.js b/tests/baselines/reference/superSymbolIndexedAccess6.js
index 8b04075c411..ee376cec2cb 100644
--- a/tests/baselines/reference/superSymbolIndexedAccess6.js
+++ b/tests/baselines/reference/superSymbolIndexedAccess6.js
@@ -31,7 +31,8 @@ var Foo = (function () {
 var Bar = (function (_super) {
     __extends(Bar, _super);
     function Bar() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Bar[symbol] = function () {
         return _super[symbol].call(this);
diff --git a/tests/baselines/reference/superWithGenericSpecialization.js b/tests/baselines/reference/superWithGenericSpecialization.js
index a54ee1bbcbc..499c0a6de1f 100644
--- a/tests/baselines/reference/superWithGenericSpecialization.js
+++ b/tests/baselines/reference/superWithGenericSpecialization.js
@@ -28,7 +28,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.call(this); // uses the type parameter type of the base class, ie string
+        var _this;
+        _this = _super.call(this) || this; // uses the type parameter type of the base class, ie string
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/superWithGenerics.js b/tests/baselines/reference/superWithGenerics.js
index b4fe56bee4c..471c7cd36ac 100644
--- a/tests/baselines/reference/superWithGenerics.js
+++ b/tests/baselines/reference/superWithGenerics.js
@@ -20,7 +20,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.call(this);
+        var _this;
+        _this = _super.call(this) || this;
     }
     return D;
 }(B));
diff --git a/tests/baselines/reference/superWithTypeArgument.js b/tests/baselines/reference/superWithTypeArgument.js
index 766b5f7920e..a4acd321f50 100644
--- a/tests/baselines/reference/superWithTypeArgument.js
+++ b/tests/baselines/reference/superWithTypeArgument.js
@@ -23,6 +23,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
+        var _this;
         _super.prototype..call(this);
     }
     return D;
diff --git a/tests/baselines/reference/superWithTypeArgument2.js b/tests/baselines/reference/superWithTypeArgument2.js
index e0d2a40633f..ca399c4de78 100644
--- a/tests/baselines/reference/superWithTypeArgument2.js
+++ b/tests/baselines/reference/superWithTypeArgument2.js
@@ -23,6 +23,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D(x) {
+        var _this;
         _super.prototype..call(this, x);
     }
     return D;
diff --git a/tests/baselines/reference/superWithTypeArgument3.js b/tests/baselines/reference/superWithTypeArgument3.js
index 586dc595b39..5a124586d0c 100644
--- a/tests/baselines/reference/superWithTypeArgument3.js
+++ b/tests/baselines/reference/superWithTypeArgument3.js
@@ -28,6 +28,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
+        var _this;
         _super.prototype..call(this);
     }
     D.prototype.bar = function () {
diff --git a/tests/baselines/reference/super_inside-object-literal-getters-and-setters.js b/tests/baselines/reference/super_inside-object-literal-getters-and-setters.js
index db6db37ac8a..ed71cebe3c7 100644
--- a/tests/baselines/reference/super_inside-object-literal-getters-and-setters.js
+++ b/tests/baselines/reference/super_inside-object-literal-getters-and-setters.js
@@ -57,7 +57,8 @@ var F = (function () {
 var SuperObjectTest = (function (_super) {
     __extends(SuperObjectTest, _super);
     function SuperObjectTest() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     SuperObjectTest.prototype.testing = function () {
         var test = {
diff --git a/tests/baselines/reference/switchStatements.js b/tests/baselines/reference/switchStatements.js
index 093a7fb2f2c..7aac6cb47e0 100644
--- a/tests/baselines/reference/switchStatements.js
+++ b/tests/baselines/reference/switchStatements.js
@@ -98,7 +98,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/systemModuleWithSuperClass.js b/tests/baselines/reference/systemModuleWithSuperClass.js
index 31cd542d2e2..59aff947e5c 100644
--- a/tests/baselines/reference/systemModuleWithSuperClass.js
+++ b/tests/baselines/reference/systemModuleWithSuperClass.js
@@ -49,7 +49,8 @@ System.register(["./foo"], function (exports_1, context_1) {
             Bar = (function (_super) {
                 __extends(Bar, _super);
                 function Bar() {
-                    _super.apply(this, arguments);
+                    var _this = _super.apply(this, arguments) || this;
+                    return _this;
                 }
                 return Bar;
             }(foo_1.Foo));
diff --git a/tests/baselines/reference/targetTypeBaseCalls.js b/tests/baselines/reference/targetTypeBaseCalls.js
index d028c04d711..a9bbc34123f 100644
--- a/tests/baselines/reference/targetTypeBaseCalls.js
+++ b/tests/baselines/reference/targetTypeBaseCalls.js
@@ -35,7 +35,8 @@ new Foo(function (s) { s = 5; }); // error, if types are applied correctly
 var Bar = (function (_super) {
     __extends(Bar, _super);
     function Bar() {
-        _super.call(this, function (s) { s = 5; });
+        var _this;
+        _this = _super.call(this, function (s) { s = 5; }) || this;
     }
     return Bar;
 }(Foo)); // error, if types are applied correctly
diff --git a/tests/baselines/reference/thisInInvalidContexts.js b/tests/baselines/reference/thisInInvalidContexts.js
index 76eeef0139c..2a86b144ae5 100644
--- a/tests/baselines/reference/thisInInvalidContexts.js
+++ b/tests/baselines/reference/thisInInvalidContexts.js
@@ -70,7 +70,8 @@ var ClassWithNoInitializer = (function (_super) {
     __extends(ClassWithNoInitializer, _super);
     //'this' in optional super call
     function ClassWithNoInitializer() {
-        _super.call(this, this); // Error
+        var _this;
+        _this = _super.call(this, this) || this; // Error
     }
     return ClassWithNoInitializer;
 }(BaseErrClass));
@@ -78,7 +79,8 @@ var ClassWithInitializer = (function (_super) {
     __extends(ClassWithInitializer, _super);
     //'this' in required super call
     function ClassWithInitializer() {
-        _super.call(this, this); // Error
+        var _this;
+        _this = _super.call(this, this) || this; // Error
         this.t = 4;
     }
     return ClassWithInitializer;
@@ -96,7 +98,8 @@ genericFunc(undefined); // Should be an error
 var ErrClass3 = (function (_super) {
     __extends(ErrClass3, _super);
     function ErrClass3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return ErrClass3;
 }(this));
diff --git a/tests/baselines/reference/thisInInvalidContextsExternalModule.js b/tests/baselines/reference/thisInInvalidContextsExternalModule.js
index 634b5ef0a20..3748ebaa42f 100644
--- a/tests/baselines/reference/thisInInvalidContextsExternalModule.js
+++ b/tests/baselines/reference/thisInInvalidContextsExternalModule.js
@@ -71,7 +71,8 @@ var ClassWithNoInitializer = (function (_super) {
     __extends(ClassWithNoInitializer, _super);
     //'this' in optional super call
     function ClassWithNoInitializer() {
-        _super.call(this, this); // error: "super" has to be called before "this" accessing
+        var _this;
+        _this = _super.call(this, this) || this; // error: "super" has to be called before "this" accessing
     }
     return ClassWithNoInitializer;
 }(BaseErrClass));
@@ -79,7 +80,8 @@ var ClassWithInitializer = (function (_super) {
     __extends(ClassWithInitializer, _super);
     //'this' in required super call
     function ClassWithInitializer() {
-        _super.call(this, this); // Error
+        var _this;
+        _this = _super.call(this, this) || this; // Error
         this.t = 4;
     }
     return ClassWithInitializer;
@@ -97,7 +99,8 @@ genericFunc(undefined); // Should be an error
 var ErrClass3 = (function (_super) {
     __extends(ErrClass3, _super);
     function ErrClass3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return ErrClass3;
 }(this));
diff --git a/tests/baselines/reference/thisInSuperCall.js b/tests/baselines/reference/thisInSuperCall.js
index 827d101c95a..91e71522e4d 100644
--- a/tests/baselines/reference/thisInSuperCall.js
+++ b/tests/baselines/reference/thisInSuperCall.js
@@ -36,14 +36,16 @@ var Base = (function () {
 var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo() {
-        _super.call(this, this); // error: "super" has to be called before "this" accessing
+        var _this;
+        _this = _super.call(this, this) || this; // error: "super" has to be called before "this" accessing
     }
     return Foo;
 }(Base));
 var Foo2 = (function (_super) {
     __extends(Foo2, _super);
     function Foo2() {
-        _super.call(this, this); // error
+        var _this;
+        _this = _super.call(this, this) || this; // error
         this.p = 0;
     }
     return Foo2;
@@ -51,7 +53,8 @@ var Foo2 = (function (_super) {
 var Foo3 = (function (_super) {
     __extends(Foo3, _super);
     function Foo3(p) {
-        _super.call(this, this); // error
+        var _this;
+        _this = _super.call(this, this) || this; // error
         this.p = p;
     }
     return Foo3;
diff --git a/tests/baselines/reference/thisInSuperCall1.js b/tests/baselines/reference/thisInSuperCall1.js
index a1cfc196ac6..8e68c47eb27 100644
--- a/tests/baselines/reference/thisInSuperCall1.js
+++ b/tests/baselines/reference/thisInSuperCall1.js
@@ -24,7 +24,8 @@ var Base = (function () {
 var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo(x) {
-        _super.call(this, this);
+        var _this;
+        _this = _super.call(this, this) || this;
         this.x = x;
     }
     return Foo;
diff --git a/tests/baselines/reference/thisInSuperCall2.js b/tests/baselines/reference/thisInSuperCall2.js
index fdffdd27d6d..6771f15c99b 100644
--- a/tests/baselines/reference/thisInSuperCall2.js
+++ b/tests/baselines/reference/thisInSuperCall2.js
@@ -33,14 +33,16 @@ var Base = (function () {
 var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo() {
-        _super.call(this, this); // error: "super" has to be called before "this" accessing
+        var _this;
+        _this = _super.call(this, this) || this; // error: "super" has to be called before "this" accessing
     }
     return Foo;
 }(Base));
 var Foo2 = (function (_super) {
     __extends(Foo2, _super);
     function Foo2() {
-        _super.call(this, this); // error
+        var _this;
+        _this = _super.call(this, this) || this; // error
         this.x = 0;
     }
     return Foo2;
diff --git a/tests/baselines/reference/thisInSuperCall3.js b/tests/baselines/reference/thisInSuperCall3.js
index 09ad6b705a9..4b6c1747d17 100644
--- a/tests/baselines/reference/thisInSuperCall3.js
+++ b/tests/baselines/reference/thisInSuperCall3.js
@@ -26,7 +26,8 @@ var Base = (function () {
 var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo() {
-        _super.call(this, this);
+        var _this;
+        _this = _super.call(this, this) || this;
         this.x = 0;
     }
     return Foo;
diff --git a/tests/baselines/reference/thisTypeInFunctions.js b/tests/baselines/reference/thisTypeInFunctions.js
index cfe1706ae99..6eaaed5c497 100644
--- a/tests/baselines/reference/thisTypeInFunctions.js
+++ b/tests/baselines/reference/thisTypeInFunctions.js
@@ -227,7 +227,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D;
 }(C));
@@ -336,7 +337,8 @@ var Base1 = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived1;
 }(Base1));
@@ -350,7 +352,8 @@ var Base2 = (function () {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Base2));
diff --git a/tests/baselines/reference/thisTypeInFunctionsNegative.js b/tests/baselines/reference/thisTypeInFunctionsNegative.js
index 4b40ca2e1e7..08e12f49dca 100644
--- a/tests/baselines/reference/thisTypeInFunctionsNegative.js
+++ b/tests/baselines/reference/thisTypeInFunctionsNegative.js
@@ -296,7 +296,8 @@ var Base1 = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived1;
 }(Base1));
@@ -310,7 +311,8 @@ var Base2 = (function () {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Base2));
diff --git a/tests/baselines/reference/tsxDynamicTagName5.js b/tests/baselines/reference/tsxDynamicTagName5.js
index a8d154998e1..9a64ef6cee6 100644
--- a/tests/baselines/reference/tsxDynamicTagName5.js
+++ b/tests/baselines/reference/tsxDynamicTagName5.js
@@ -30,7 +30,8 @@ var React = require("react");
 var Text = (function (_super) {
     __extends(Text, _super);
     function Text() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this._tagName = 'div';
     }
     Text.prototype.render = function () {
diff --git a/tests/baselines/reference/tsxDynamicTagName7.js b/tests/baselines/reference/tsxDynamicTagName7.js
index dbe171f9682..30500b37ce5 100644
--- a/tests/baselines/reference/tsxDynamicTagName7.js
+++ b/tests/baselines/reference/tsxDynamicTagName7.js
@@ -30,7 +30,8 @@ var React = require("react");
 var Text = (function (_super) {
     __extends(Text, _super);
     function Text() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this._tagName = 'div';
     }
     Text.prototype.render = function () {
diff --git a/tests/baselines/reference/tsxDynamicTagName8.js b/tests/baselines/reference/tsxDynamicTagName8.js
index e6f63b6a9bf..a6cf3bb45b8 100644
--- a/tests/baselines/reference/tsxDynamicTagName8.js
+++ b/tests/baselines/reference/tsxDynamicTagName8.js
@@ -30,7 +30,8 @@ var React = require("react");
 var Text = (function (_super) {
     __extends(Text, _super);
     function Text() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this._tagName = 'div';
     }
     Text.prototype.render = function () {
diff --git a/tests/baselines/reference/tsxDynamicTagName9.js b/tests/baselines/reference/tsxDynamicTagName9.js
index 589cc7cd226..aa63e614d15 100644
--- a/tests/baselines/reference/tsxDynamicTagName9.js
+++ b/tests/baselines/reference/tsxDynamicTagName9.js
@@ -30,7 +30,8 @@ var React = require("react");
 var Text = (function (_super) {
     __extends(Text, _super);
     function Text() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this._tagName = 'div';
     }
     Text.prototype.render = function () {
diff --git a/tests/baselines/reference/tsxExternalModuleEmit1.js b/tests/baselines/reference/tsxExternalModuleEmit1.js
index 0d4e58d7008..0f6b8716ed0 100644
--- a/tests/baselines/reference/tsxExternalModuleEmit1.js
+++ b/tests/baselines/reference/tsxExternalModuleEmit1.js
@@ -42,7 +42,8 @@ var React = require("react");
 var Button = (function (_super) {
     __extends(Button, _super);
     function Button() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Button.prototype.render = function () {
         return <button>Some button</button>;
@@ -63,7 +64,8 @@ var button_1 = require("./button");
 var App = (function (_super) {
     __extends(App, _super);
     function App() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     App.prototype.render = function () {
         return <button_1.Button />;
diff --git a/tests/baselines/reference/tsxStatelessFunctionComponents2.js b/tests/baselines/reference/tsxStatelessFunctionComponents2.js
index b93832567d5..f7ac96cff1f 100644
--- a/tests/baselines/reference/tsxStatelessFunctionComponents2.js
+++ b/tests/baselines/reference/tsxStatelessFunctionComponents2.js
@@ -52,7 +52,8 @@ function Greet(x) {
 var BigGreeter = (function (_super) {
     __extends(BigGreeter, _super);
     function BigGreeter() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     BigGreeter.prototype.render = function () {
         return <div></div>;
diff --git a/tests/baselines/reference/tsxUnionTypeComponent1.js b/tests/baselines/reference/tsxUnionTypeComponent1.js
index 444542068be..56a6896f052 100644
--- a/tests/baselines/reference/tsxUnionTypeComponent1.js
+++ b/tests/baselines/reference/tsxUnionTypeComponent1.js
@@ -35,7 +35,8 @@ var React = require("react");
 var MyComponent = (function (_super) {
     __extends(MyComponent, _super);
     function MyComponent() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     MyComponent.prototype.render = function () {
         var AnyComponent = this.props.AnyComponent;
@@ -49,7 +50,8 @@ React.createElement(MyComponent, { AnyComponent: function () { return React.crea
 var MyButtonComponent = (function (_super) {
     __extends(MyButtonComponent, _super);
     function MyButtonComponent() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return MyButtonComponent;
 }(React.Component));
diff --git a/tests/baselines/reference/typeAssertions.js b/tests/baselines/reference/typeAssertions.js
index 1d33fa927a7..083cb5e94b3 100644
--- a/tests/baselines/reference/typeAssertions.js
+++ b/tests/baselines/reference/typeAssertions.js
@@ -74,7 +74,8 @@ var SomeBase = (function () {
 var SomeDerived = (function (_super) {
     __extends(SomeDerived, _super);
     function SomeDerived() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return SomeDerived;
 }(SomeBase));
diff --git a/tests/baselines/reference/typeGuardFunction.js b/tests/baselines/reference/typeGuardFunction.js
index fcd6435ca1d..45bf0853b13 100644
--- a/tests/baselines/reference/typeGuardFunction.js
+++ b/tests/baselines/reference/typeGuardFunction.js
@@ -102,7 +102,8 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/typeGuardFunctionErrors.js b/tests/baselines/reference/typeGuardFunctionErrors.js
index f3ff5ffab4a..727640ee8af 100644
--- a/tests/baselines/reference/typeGuardFunctionErrors.js
+++ b/tests/baselines/reference/typeGuardFunctionErrors.js
@@ -164,7 +164,8 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/typeGuardFunctionGenerics.js b/tests/baselines/reference/typeGuardFunctionGenerics.js
index 2b5bd5e8265..dad77edf232 100644
--- a/tests/baselines/reference/typeGuardFunctionGenerics.js
+++ b/tests/baselines/reference/typeGuardFunctionGenerics.js
@@ -52,7 +52,8 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/typeGuardFunctionOfFormThis.js b/tests/baselines/reference/typeGuardFunctionOfFormThis.js
index ad85f679e0a..eec648976c6 100644
--- a/tests/baselines/reference/typeGuardFunctionOfFormThis.js
+++ b/tests/baselines/reference/typeGuardFunctionOfFormThis.js
@@ -161,7 +161,8 @@ var RoyalGuard = (function () {
 var LeadGuard = (function (_super) {
     __extends(LeadGuard, _super);
     function LeadGuard() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     LeadGuard.prototype.lead = function () { };
     ;
@@ -170,7 +171,8 @@ var LeadGuard = (function (_super) {
 var FollowerGuard = (function (_super) {
     __extends(FollowerGuard, _super);
     function FollowerGuard() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     FollowerGuard.prototype.follow = function () { };
     ;
@@ -224,7 +226,8 @@ var ArrowGuard = (function () {
 var ArrowElite = (function (_super) {
     __extends(ArrowElite, _super);
     function ArrowElite() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     ArrowElite.prototype.defend = function () { };
     return ArrowElite;
@@ -232,7 +235,8 @@ var ArrowElite = (function (_super) {
 var ArrowMedic = (function (_super) {
     __extends(ArrowMedic, _super);
     function ArrowMedic() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     ArrowMedic.prototype.heal = function () { };
     return ArrowMedic;
@@ -266,7 +270,8 @@ var MimicGuard = (function () {
 var MimicLeader = (function (_super) {
     __extends(MimicLeader, _super);
     function MimicLeader() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     MimicLeader.prototype.lead = function () { };
     return MimicLeader;
@@ -274,7 +279,8 @@ var MimicLeader = (function (_super) {
 var MimicFollower = (function (_super) {
     __extends(MimicFollower, _super);
     function MimicFollower() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     MimicFollower.prototype.follow = function () { };
     return MimicFollower;
diff --git a/tests/baselines/reference/typeGuardFunctionOfFormThisErrors.js b/tests/baselines/reference/typeGuardFunctionOfFormThisErrors.js
index 73622bf60cc..a82d3d2527f 100644
--- a/tests/baselines/reference/typeGuardFunctionOfFormThisErrors.js
+++ b/tests/baselines/reference/typeGuardFunctionOfFormThisErrors.js
@@ -79,7 +79,8 @@ var RoyalGuard = (function () {
 var LeadGuard = (function (_super) {
     __extends(LeadGuard, _super);
     function LeadGuard() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     LeadGuard.prototype.lead = function () { };
     ;
@@ -88,7 +89,8 @@ var LeadGuard = (function (_super) {
 var FollowerGuard = (function (_super) {
     __extends(FollowerGuard, _super);
     function FollowerGuard() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     FollowerGuard.prototype.follow = function () { };
     ;
diff --git a/tests/baselines/reference/typeGuardOfFormInstanceOf.js b/tests/baselines/reference/typeGuardOfFormInstanceOf.js
index a6881cf3cea..a94d5fe93e7 100644
--- a/tests/baselines/reference/typeGuardOfFormInstanceOf.js
+++ b/tests/baselines/reference/typeGuardOfFormInstanceOf.js
@@ -91,7 +91,8 @@ var C2 = (function () {
 var D1 = (function (_super) {
     __extends(D1, _super);
     function D1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D1;
 }(C1));
diff --git a/tests/baselines/reference/typeGuardOfFormIsType.js b/tests/baselines/reference/typeGuardOfFormIsType.js
index 3f55b9d41ea..2d83a62ad3e 100644
--- a/tests/baselines/reference/typeGuardOfFormIsType.js
+++ b/tests/baselines/reference/typeGuardOfFormIsType.js
@@ -56,7 +56,8 @@ var C2 = (function () {
 var D1 = (function (_super) {
     __extends(D1, _super);
     function D1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D1;
 }(C1));
diff --git a/tests/baselines/reference/typeGuardOfFormThisMember.js b/tests/baselines/reference/typeGuardOfFormThisMember.js
index 9d71613ed8f..63c79ce4c91 100644
--- a/tests/baselines/reference/typeGuardOfFormThisMember.js
+++ b/tests/baselines/reference/typeGuardOfFormThisMember.js
@@ -118,7 +118,8 @@ var Test;
     var File = (function (_super) {
         __extends(File, _super);
         function File(path, content) {
-            _super.call(this, path);
+            var _this;
+            _this = _super.call(this, path) || this;
             this.content = content;
         }
         return File;
@@ -127,7 +128,8 @@ var Test;
     var Directory = (function (_super) {
         __extends(Directory, _super);
         function Directory() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Directory;
     }(FileSystemObject));
diff --git a/tests/baselines/reference/typeGuardOfFormThisMemberErrors.js b/tests/baselines/reference/typeGuardOfFormThisMemberErrors.js
index 5991fdd3169..5c28921a6a7 100644
--- a/tests/baselines/reference/typeGuardOfFormThisMemberErrors.js
+++ b/tests/baselines/reference/typeGuardOfFormThisMemberErrors.js
@@ -68,7 +68,8 @@ var Test;
     var File = (function (_super) {
         __extends(File, _super);
         function File(path, content) {
-            _super.call(this, path);
+            var _this;
+            _this = _super.call(this, path) || this;
             this.content = content;
         }
         return File;
@@ -77,7 +78,8 @@ var Test;
     var Directory = (function (_super) {
         __extends(Directory, _super);
         function Directory() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return Directory;
     }(FileSystemObject));
diff --git a/tests/baselines/reference/typeMatch2.js b/tests/baselines/reference/typeMatch2.js
index 57ba67752e2..03408c6196b 100644
--- a/tests/baselines/reference/typeMatch2.js
+++ b/tests/baselines/reference/typeMatch2.js
@@ -65,7 +65,8 @@ var Animal = (function () {
 var Giraffe = (function (_super) {
     __extends(Giraffe, _super);
     function Giraffe() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Giraffe;
 }(Animal));
diff --git a/tests/baselines/reference/typeOfSuperCall.js b/tests/baselines/reference/typeOfSuperCall.js
index 94215d4ae1b..70ace4becb4 100644
--- a/tests/baselines/reference/typeOfSuperCall.js
+++ b/tests/baselines/reference/typeOfSuperCall.js
@@ -22,7 +22,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var x = _super.call(this);
+        var _this;
+        var x = _this = _super.call(this) || this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/typeParameterAsBaseClass.js b/tests/baselines/reference/typeParameterAsBaseClass.js
index a01b6a0cac2..d67259304c3 100644
--- a/tests/baselines/reference/typeParameterAsBaseClass.js
+++ b/tests/baselines/reference/typeParameterAsBaseClass.js
@@ -11,7 +11,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(T));
diff --git a/tests/baselines/reference/typeParameterAsBaseType.js b/tests/baselines/reference/typeParameterAsBaseType.js
index 9c3a9bcfcd0..24f8789a82d 100644
--- a/tests/baselines/reference/typeParameterAsBaseType.js
+++ b/tests/baselines/reference/typeParameterAsBaseType.js
@@ -21,14 +21,16 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C;
 }(T));
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }(U));
diff --git a/tests/baselines/reference/typeParameterExtendingUnion1.js b/tests/baselines/reference/typeParameterExtendingUnion1.js
index 75614f46d21..55bc51bbdbb 100644
--- a/tests/baselines/reference/typeParameterExtendingUnion1.js
+++ b/tests/baselines/reference/typeParameterExtendingUnion1.js
@@ -27,14 +27,16 @@ var Animal = (function () {
 var Cat = (function (_super) {
     __extends(Cat, _super);
     function Cat() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Cat;
 }(Animal));
 var Dog = (function (_super) {
     __extends(Dog, _super);
     function Dog() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Dog;
 }(Animal));
diff --git a/tests/baselines/reference/typeParameterExtendingUnion2.js b/tests/baselines/reference/typeParameterExtendingUnion2.js
index b32c43bc5ec..75f62e94c67 100644
--- a/tests/baselines/reference/typeParameterExtendingUnion2.js
+++ b/tests/baselines/reference/typeParameterExtendingUnion2.js
@@ -27,14 +27,16 @@ var Animal = (function () {
 var Cat = (function (_super) {
     __extends(Cat, _super);
     function Cat() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Cat;
 }(Animal));
 var Dog = (function (_super) {
     __extends(Dog, _super);
     function Dog() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Dog;
 }(Animal));
diff --git a/tests/baselines/reference/typeRelationships.js b/tests/baselines/reference/typeRelationships.js
index 6f8f1ccd4cc..43c1f7ee146 100644
--- a/tests/baselines/reference/typeRelationships.js
+++ b/tests/baselines/reference/typeRelationships.js
@@ -72,7 +72,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this;
+        _this = _super.apply(this, arguments) || this;
         this.self1 = this;
         this.self2 = this.self;
         this.self3 = this.foo();
diff --git a/tests/baselines/reference/typeValueConflict1.js b/tests/baselines/reference/typeValueConflict1.js
index eaca97d31dd..a1ecef212da 100644
--- a/tests/baselines/reference/typeValueConflict1.js
+++ b/tests/baselines/reference/typeValueConflict1.js
@@ -33,7 +33,8 @@ var M2;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(M1.A));
diff --git a/tests/baselines/reference/typeValueConflict2.js b/tests/baselines/reference/typeValueConflict2.js
index d89ab0fd357..a0cfeda07ec 100644
--- a/tests/baselines/reference/typeValueConflict2.js
+++ b/tests/baselines/reference/typeValueConflict2.js
@@ -40,7 +40,8 @@ var M2;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(M1.A));
@@ -51,7 +52,8 @@ var M3;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return B;
     }(M1.A));
diff --git a/tests/baselines/reference/typeofClass2.js b/tests/baselines/reference/typeofClass2.js
index a0c30c1b166..b3da31103df 100644
--- a/tests/baselines/reference/typeofClass2.js
+++ b/tests/baselines/reference/typeofClass2.js
@@ -37,7 +37,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     D.baz = function (x) { };
     D.prototype.foo = function () { };
diff --git a/tests/baselines/reference/typesWithSpecializedCallSignatures.js b/tests/baselines/reference/typesWithSpecializedCallSignatures.js
index e83fd36ae62..853cb5eafd7 100644
--- a/tests/baselines/reference/typesWithSpecializedCallSignatures.js
+++ b/tests/baselines/reference/typesWithSpecializedCallSignatures.js
@@ -56,14 +56,16 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived1;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/typesWithSpecializedConstructSignatures.js b/tests/baselines/reference/typesWithSpecializedConstructSignatures.js
index 63d5e9bb5b2..99314597440 100644
--- a/tests/baselines/reference/typesWithSpecializedConstructSignatures.js
+++ b/tests/baselines/reference/typesWithSpecializedConstructSignatures.js
@@ -54,14 +54,16 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived1;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/undeclaredBase.js b/tests/baselines/reference/undeclaredBase.js
index 3dd27a3dbfb..64117b1935a 100644
--- a/tests/baselines/reference/undeclaredBase.js
+++ b/tests/baselines/reference/undeclaredBase.js
@@ -14,7 +14,8 @@ var M;
     var C = (function (_super) {
         __extends(C, _super);
         function C() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return C;
     }(M.I));
diff --git a/tests/baselines/reference/undefinedIsSubtypeOfEverything.js b/tests/baselines/reference/undefinedIsSubtypeOfEverything.js
index 513464daa85..451aec91aff 100644
--- a/tests/baselines/reference/undefinedIsSubtypeOfEverything.js
+++ b/tests/baselines/reference/undefinedIsSubtypeOfEverything.js
@@ -136,105 +136,120 @@ var Base = (function () {
 var D0 = (function (_super) {
     __extends(D0, _super);
     function D0() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D0;
 }(Base));
 var DA = (function (_super) {
     __extends(DA, _super);
     function DA() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return DA;
 }(Base));
 var D1 = (function (_super) {
     __extends(D1, _super);
     function D1() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D1;
 }(Base));
 var D1A = (function (_super) {
     __extends(D1A, _super);
     function D1A() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D1A;
 }(Base));
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D2;
 }(Base));
 var D2A = (function (_super) {
     __extends(D2A, _super);
     function D2A() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D2A;
 }(Base));
 var D3 = (function (_super) {
     __extends(D3, _super);
     function D3() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D3;
 }(Base));
 var D3A = (function (_super) {
     __extends(D3A, _super);
     function D3A() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D3A;
 }(Base));
 var D4 = (function (_super) {
     __extends(D4, _super);
     function D4() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D4;
 }(Base));
 var D5 = (function (_super) {
     __extends(D5, _super);
     function D5() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D5;
 }(Base));
 var D6 = (function (_super) {
     __extends(D6, _super);
     function D6() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D6;
 }(Base));
 var D7 = (function (_super) {
     __extends(D7, _super);
     function D7() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D7;
 }(Base));
 var D8 = (function (_super) {
     __extends(D8, _super);
     function D8() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D8;
 }(Base));
 var D9 = (function (_super) {
     __extends(D9, _super);
     function D9() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D9;
 }(Base));
 var D10 = (function (_super) {
     __extends(D10, _super);
     function D10() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D10;
 }(Base));
@@ -245,7 +260,8 @@ var E;
 var D11 = (function (_super) {
     __extends(D11, _super);
     function D11() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D11;
 }(Base));
@@ -257,7 +273,8 @@ var f;
 var D12 = (function (_super) {
     __extends(D12, _super);
     function D12() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D12;
 }(Base));
@@ -273,21 +290,24 @@ var c;
 var D13 = (function (_super) {
     __extends(D13, _super);
     function D13() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D13;
 }(Base));
 var D14 = (function (_super) {
     __extends(D14, _super);
     function D14() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D14;
 }(Base));
 var D15 = (function (_super) {
     __extends(D15, _super);
     function D15() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D15;
 }(Base));
@@ -297,14 +317,16 @@ var D15 = (function (_super) {
 var D16 = (function (_super) {
     __extends(D16, _super);
     function D16() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D16;
 }(Base));
 var D17 = (function (_super) {
     __extends(D17, _super);
     function D17() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return D17;
 }(Base));
diff --git a/tests/baselines/reference/underscoreMapFirst.js b/tests/baselines/reference/underscoreMapFirst.js
index a615faea805..61f1bf2c9f9 100644
--- a/tests/baselines/reference/underscoreMapFirst.js
+++ b/tests/baselines/reference/underscoreMapFirst.js
@@ -57,7 +57,8 @@ var __extends = (this && this.__extends) || function (d, b) {
 var MyView = (function (_super) {
     __extends(MyView, _super);
     function MyView() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     MyView.prototype.getDataSeries = function () {
         var data = this.model.get("data");
diff --git a/tests/baselines/reference/unionTypeEquivalence.js b/tests/baselines/reference/unionTypeEquivalence.js
index 1ff47f68e5f..b0be82122de 100644
--- a/tests/baselines/reference/unionTypeEquivalence.js
+++ b/tests/baselines/reference/unionTypeEquivalence.js
@@ -34,7 +34,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     D.prototype.foo = function () { };
     return D;
diff --git a/tests/baselines/reference/unionTypeFromArrayLiteral.js b/tests/baselines/reference/unionTypeFromArrayLiteral.js
index 95dd9d39853..72cf61f72fd 100644
--- a/tests/baselines/reference/unionTypeFromArrayLiteral.js
+++ b/tests/baselines/reference/unionTypeFromArrayLiteral.js
@@ -54,7 +54,8 @@ var D = (function () {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     E.prototype.foo3 = function () { };
     return E;
@@ -62,7 +63,8 @@ var E = (function (_super) {
 var F = (function (_super) {
     __extends(F, _super);
     function F() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     F.prototype.foo4 = function () { };
     return F;
diff --git a/tests/baselines/reference/unionTypesAssignability.js b/tests/baselines/reference/unionTypesAssignability.js
index c7105608004..fafc4ec85fa 100644
--- a/tests/baselines/reference/unionTypesAssignability.js
+++ b/tests/baselines/reference/unionTypesAssignability.js
@@ -88,7 +88,8 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     D.prototype.foo1 = function () { };
     return D;
@@ -96,7 +97,8 @@ var D = (function (_super) {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     E.prototype.foo2 = function () { };
     return E;
diff --git a/tests/baselines/reference/unknownSymbols1.js b/tests/baselines/reference/unknownSymbols1.js
index 03ed4990c29..46ee4ed02d5 100644
--- a/tests/baselines/reference/unknownSymbols1.js
+++ b/tests/baselines/reference/unknownSymbols1.js
@@ -63,7 +63,8 @@ var C3 = (function () {
 var C4 = (function (_super) {
     __extends(C4, _super);
     function C4() {
-        _super.call(this, asdf);
+        var _this;
+        _this = _super.call(this, asdf) || this;
     }
     return C4;
 }(C3));
diff --git a/tests/baselines/reference/unspecializedConstraints.js b/tests/baselines/reference/unspecializedConstraints.js
index 7b3938c7099..b2ea2cac9eb 100644
--- a/tests/baselines/reference/unspecializedConstraints.js
+++ b/tests/baselines/reference/unspecializedConstraints.js
@@ -169,7 +169,8 @@ var ts;
     var Type = (function (_super) {
         __extends(Type, _super);
         function Type() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         Type.prototype.equals = function (that) {
             if (this === that)
@@ -233,7 +234,8 @@ var ts;
     var Property = (function (_super) {
         __extends(Property, _super);
         function Property(name, type, flags) {
-            _super.call(this);
+            var _this;
+            _this = _super.call(this) || this;
             this.name = name;
             this.type = type;
             this.flags = flags;
@@ -253,7 +255,8 @@ var ts;
     var Signature = (function (_super) {
         __extends(Signature, _super);
         function Signature(typeParameters, parameters, returnType) {
-            _super.call(this);
+            var _this;
+            _this = _super.call(this) || this;
             this.typeParameters = typeParameters;
             this.parameters = parameters;
             this.returnType = returnType;
@@ -273,7 +276,8 @@ var ts;
     var Parameter = (function (_super) {
         __extends(Parameter, _super);
         function Parameter(name, type, flags) {
-            _super.call(this);
+            var _this;
+            _this = _super.call(this) || this;
             this.name = name;
             this.type = type;
             this.flags = flags;
diff --git a/tests/baselines/reference/untypedFunctionCallsWithTypeParameters1.js b/tests/baselines/reference/untypedFunctionCallsWithTypeParameters1.js
index e991db69367..324dc784b67 100644
--- a/tests/baselines/reference/untypedFunctionCallsWithTypeParameters1.js
+++ b/tests/baselines/reference/untypedFunctionCallsWithTypeParameters1.js
@@ -70,7 +70,8 @@ var r4 = c2(); // should be an error
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     return C2;
 }(Function)); // error
diff --git a/tests/baselines/reference/unusedClassesinNamespace4.js b/tests/baselines/reference/unusedClassesinNamespace4.js
index 65198c1c1aa..3c1dd16874e 100644
--- a/tests/baselines/reference/unusedClassesinNamespace4.js
+++ b/tests/baselines/reference/unusedClassesinNamespace4.js
@@ -36,7 +36,8 @@ var Validation;
     var c3 = (function (_super) {
         __extends(c3, _super);
         function c3() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return c3;
     }(c1));
diff --git a/tests/baselines/reference/unusedIdentifiersConsolidated1.js b/tests/baselines/reference/unusedIdentifiersConsolidated1.js
index 521f17bf5ef..fd7d859ac37 100644
--- a/tests/baselines/reference/unusedIdentifiersConsolidated1.js
+++ b/tests/baselines/reference/unusedIdentifiersConsolidated1.js
@@ -168,7 +168,8 @@ var Greeter;
     var class2 = (function (_super) {
         __extends(class2, _super);
         function class2() {
-            _super.apply(this, arguments);
+            var _this = _super.apply(this, arguments) || this;
+            return _this;
         }
         return class2;
     }(class1));
diff --git a/tests/baselines/reference/validUseOfThisInSuper.js b/tests/baselines/reference/validUseOfThisInSuper.js
index 027ba254ae0..96802932f12 100644
--- a/tests/baselines/reference/validUseOfThisInSuper.js
+++ b/tests/baselines/reference/validUseOfThisInSuper.js
@@ -24,8 +24,8 @@ var Base = (function () {
 var Super = (function (_super) {
     __extends(Super, _super);
     function Super() {
-        var _this = this;
-        _super.call(this, (function () { return _this; })()); // ok since this is not the case: The constructor declares parameter properties or the containing class declares instance member variables with initializers.
+        var _this;
+        _this = _super.call(this, (function () { return _this; })()) || this; // ok since this is not the case: The constructor declares parameter properties or the containing class declares instance member variables with initializers.
     }
     return Super;
 }(Base));
diff --git a/tests/baselines/reference/varArgsOnConstructorTypes.js b/tests/baselines/reference/varArgsOnConstructorTypes.js
index db8f566702a..e892cc28a3c 100644
--- a/tests/baselines/reference/varArgsOnConstructorTypes.js
+++ b/tests/baselines/reference/varArgsOnConstructorTypes.js
@@ -41,7 +41,8 @@ define(["require", "exports"], function (require, exports) {
     var B = (function (_super) {
         __extends(B, _super);
         function B(element, url) {
-            _super.call(this, element);
+            var _this;
+            _this = _super.call(this, element) || this;
             this.p1 = element;
             this.p2 = url;
         }

From d778e78f1ef118befdd2ae4866864bfd1465f389 Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Fri, 2 Sep 2016 00:08:26 -0700
Subject: [PATCH 03/47] Transform other instances of 'this' to '_this' when in
 the constructor of a derived class.

---
 src/compiler/transformers/es6.ts | 28 ++++++++++++++++++++++------
 1 file changed, 22 insertions(+), 6 deletions(-)

diff --git a/src/compiler/transformers/es6.ts b/src/compiler/transformers/es6.ts
index aab894dc4ff..5dd2b154c01 100644
--- a/src/compiler/transformers/es6.ts
+++ b/src/compiler/transformers/es6.ts
@@ -722,7 +722,10 @@ namespace ts {
         function addConstructor(statements: Statement[], node: ClassExpression | ClassDeclaration, extendsClauseElement: ExpressionWithTypeArguments): void {
             const constructor = getFirstConstructorWithBody(node);
             const hasSynthesizedSuper = hasSynthesizedDefaultSuperCall(constructor, extendsClauseElement !== undefined);
-            statements.push(
+            const savedUseCapturedThis = useCapturedThis;
+            useCapturedThis = true;
+
+            const constructorFunction =
                 createFunctionDeclaration(
                     /*decorators*/ undefined,
                     /*modifiers*/ undefined,
@@ -733,8 +736,13 @@ namespace ts {
                     /*type*/ undefined,
                     transformConstructorBody(constructor, node, extendsClauseElement, hasSynthesizedSuper),
                     /*location*/ constructor || node
-                )
-            );
+                );
+
+            if (extendsClauseElement) {
+                setNodeEmitFlags(constructorFunction, NodeEmitFlags.CapturesThis);
+            }
+            useCapturedThis = savedUseCapturedThis;
+            statements.push(constructorFunction);
         }
 
         /**
@@ -769,6 +777,7 @@ namespace ts {
         function transformConstructorBody(constructor: ConstructorDeclaration, node: ClassDeclaration | ClassExpression, extendsClauseElement: ExpressionWithTypeArguments, hasSynthesizedSuper: boolean) {
             const statements: Statement[] = [];
             startLexicalEnvironment();
+
             if (constructor) {
                 declareOrCaptureThisForConstructorIfNeeded(statements, constructor, !!extendsClauseElement);
                 addDefaultValueAssignmentsIfNeeded(statements, constructor);
@@ -830,12 +839,14 @@ namespace ts {
             // If this is the case, or if the class has an `extends` clause but no
             // constructor, we emit a synthesized call to `_super`.
             if (constructor ? hasSynthesizedSuper : extendsClauseElement) {
+                const actualThis = createThis();
+                setNodeEmitFlags(actualThis, NodeEmitFlags.NoSubstitution);
                 const superCall = createFunctionApply(
                     createIdentifier("_super"),
-                    createThis(),
+                    actualThis,
                     createIdentifier("arguments"),
                 );
-                const superReturnValueOrThis = createLogicalOr(superCall, createThis());
+                const superReturnValueOrThis = createLogicalOr(superCall, actualThis);
 
                 statements.push(
                     createVariableStatement(
@@ -2504,6 +2515,9 @@ namespace ts {
             // because we contain a SpreadElementExpression.
 
             const { target, thisArg } = createCallBinding(node.expression, hoistVariableDeclaration);
+            if (node.expression.kind === SyntaxKind.SuperKeyword) {
+                setNodeEmitFlags(thisArg, NodeEmitFlags.NoSubstitution);
+            }
             let resultingCall: CallExpression | BinaryExpression;
             if (node.transformFlags & TransformFlags.ContainsSpreadElementExpression) {
                 // [source]
@@ -2546,11 +2560,13 @@ namespace ts {
             }
 
             if (node.expression.kind === SyntaxKind.SuperKeyword) {
+                const actualThis = createThis();
+                setNodeEmitFlags(actualThis, NodeEmitFlags.NoSubstitution);
                 return createAssignment(
                     createIdentifier("_this"),
                     createLogicalOr(
                         resultingCall,
-                        createThis()
+                        actualThis
                     )
                 );
             }

From c21cc24c44689875f1a0104a366ac65ff5975361 Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Fri, 2 Sep 2016 00:12:03 -0700
Subject: [PATCH 04/47] Accepted baselines for all tests apart from one with
 source map changes.

---
 tests/baselines/reference/abstractProperty.js |   4 +-
 .../reference/abstractPropertyNegative.js     |   6 +-
 .../accessOverriddenBaseClassMember1.js       |   2 +-
 ...aliasUsageInTypeArgumentOfExtendsClause.js |   2 +-
 tests/baselines/reference/autolift4.js        |   2 +-
 tests/baselines/reference/baseCheck.js        |  12 +-
 tests/baselines/reference/bases.js            |   2 +-
 .../reference/bestCommonTypeOfTuple2.js       |   2 +-
 .../checkSuperCallBeforeThisAccessing1.js     |   6 +-
 .../checkSuperCallBeforeThisAccessing2.js     |   6 +-
 .../checkSuperCallBeforeThisAccessing3.js     |   4 +-
 .../checkSuperCallBeforeThisAccessing4.js     |   4 +-
 .../checkSuperCallBeforeThisAccessing5.js     |   2 +-
 .../checkSuperCallBeforeThisAccessing8.js     |   2 +-
 .../classConstructorAccessibility2.js         |   6 +-
 ...classConstructorParametersAccessibility.js |   2 +-
 ...lassConstructorParametersAccessibility2.js |   2 +-
 ...lassConstructorParametersAccessibility3.js |   4 +-
 tests/baselines/reference/classExpression3.js |   4 +-
 .../reference/classExtendingClassLikeType.js  |  12 +-
 .../reference/classSideInheritance3.js        |   2 +-
 tests/baselines/reference/classUpdateTests.js |  12 +-
 ...ollisionSuperAndLocalFunctionInProperty.js |   2 +-
 .../collisionSuperAndLocalVarInProperty.js    |   4 +-
 .../reference/collisionSuperAndParameter.js   |   2 +-
 ...perAndPropertyNameAsConstuctorParameter.js |   4 +-
 .../reference/computedPropertyNames30_ES5.js  |   2 +-
 tests/baselines/reference/constructorArgs.js  |   2 +-
 .../reference/declFileGenericType2.js         |   2 +-
 ...derivedClassConstructorWithoutSuperCall.js |   2 +-
 .../derivedClassParameterProperties.js        |  34 +-
 ...dClassSuperCallsInNonConstructorMembers.js |   2 +-
 .../derivedClassSuperCallsWithThisArg.js      |  10 +-
 .../derivedClassWithoutExplicitConstructor.js |   8 +-
 ...derivedClassWithoutExplicitConstructor2.js |   8 +-
 ...derivedClassWithoutExplicitConstructor3.js |  16 +-
 ...BeforeEmitParameterPropertyDeclaration1.js |   2 +-
 ...SuperCallBeforeEmitPropertyDeclaration1.js |   2 +-
 ...arationAndParameterPropertyDeclaration1.js |   4 +-
 tests/baselines/reference/errorSuperCalls.js  |   4 +-
 tests/baselines/reference/es6ClassTest.js     |  12 +-
 ...ericRecursiveImplicitConstructorErrors3.js |   2 +-
 .../illegalSuperCallsInConstructor.js         |   4 +-
 .../interfaceExtendsClassWithPrivate2.js      |   6 +-
 ...objectCreationOfElementAccessExpression.js |  16 +-
 tests/baselines/reference/optionalMethods.js  |   2 +-
 .../reference/optionalParameterProperty.js    |   2 +-
 .../overloadOnConstConstraintChecks4.js       |   2 +-
 tests/baselines/reference/parserAstSpans1.js  |   4 +-
 .../baselines/reference/parserRealSource10.js |  24 +-
 .../baselines/reference/parserRealSource11.js | 308 +++++++++---------
 tests/baselines/reference/parserharness.js    |   8 +-
 .../privateInstanceMemberAccessibility.js     |   4 +-
 .../privateStaticMemberAccessibility.js       |   2 +-
 .../readonlyConstructorAssignment.js          |  10 +-
 tests/baselines/reference/scopeTests.js       |   4 +-
 .../baselines/reference/staticInheritance.js  |   4 +-
 tests/baselines/reference/staticPropSuper.js  |   6 +-
 .../reference/strictModeInConstructor.js      |   6 +-
 tests/baselines/reference/superAccess2.js     |   4 +-
 .../reference/superCallArgsMustMatch.js       |   2 +-
 .../superCallBeforeThisAccessing1.js          |   2 +-
 .../superCallBeforeThisAccessing3.js          |   2 +-
 .../superCallBeforeThisAccessing4.js          |   4 +-
 .../superCallBeforeThisAccessing5.js          |   2 +-
 .../superCallBeforeThisAccessing6.js          |   2 +-
 .../superCallBeforeThisAccessing7.js          |   2 +-
 .../superCallBeforeThisAccessing8.js          |   2 +-
 .../reference/superCallInNonStaticMethod.js   |   6 +-
 .../reference/superCallOutsideConstructor.js  |   4 +-
 .../superCallParameterContextualTyping3.js    |   2 +-
 tests/baselines/reference/superCalls.js       |   2 +-
 tests/baselines/reference/superErrors.js      |   2 +-
 .../reference/superInConstructorParam1.js     |   2 +-
 tests/baselines/reference/superInLambdas.js   |  10 +-
 .../reference/superPropertyAccess1.js         |   2 +-
 .../reference/superPropertyAccess2.js         |   2 +-
 .../reference/superPropertyAccessNoError.js   |   2 +-
 .../reference/superPropertyAccess_ES5.js      |   2 +-
 .../reference/superWithTypeArgument.js        |   2 +-
 .../reference/superWithTypeArgument2.js       |   2 +-
 .../reference/superWithTypeArgument3.js       |   2 +-
 .../reference/thisInInvalidContexts.js        |   6 +-
 .../thisInInvalidContextsExternalModule.js    |   6 +-
 tests/baselines/reference/thisInSuperCall.js  |  10 +-
 tests/baselines/reference/thisInSuperCall1.js |   4 +-
 tests/baselines/reference/thisInSuperCall2.js |   6 +-
 tests/baselines/reference/thisInSuperCall3.js |   4 +-
 .../baselines/reference/tsxDynamicTagName5.js |   2 +-
 .../baselines/reference/tsxDynamicTagName7.js |   2 +-
 .../baselines/reference/tsxDynamicTagName8.js |   2 +-
 .../baselines/reference/tsxDynamicTagName9.js |   2 +-
 .../reference/typeGuardOfFormThisMember.js    |   2 +-
 .../typeGuardOfFormThisMemberErrors.js        |   2 +-
 .../baselines/reference/typeRelationships.js  |   8 +-
 .../reference/unspecializedConstraints.js     |  18 +-
 .../reference/varArgsOnConstructorTypes.js    |   4 +-
 97 files changed, 389 insertions(+), 389 deletions(-)

diff --git a/tests/baselines/reference/abstractProperty.js b/tests/baselines/reference/abstractProperty.js
index 803df9f1d56..d9bfd5eb05f 100644
--- a/tests/baselines/reference/abstractProperty.js
+++ b/tests/baselines/reference/abstractProperty.js
@@ -37,8 +37,8 @@ var C = (function (_super) {
     function C() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.raw = "edge";
-        this.ro = "readonly please";
+        _this.raw = "edge";
+        _this.ro = "readonly please";
     }
     Object.defineProperty(C.prototype, "prop", {
         get: function () { return "foo"; },
diff --git a/tests/baselines/reference/abstractPropertyNegative.js b/tests/baselines/reference/abstractPropertyNegative.js
index d6e1ce1813f..e94d9492fdb 100644
--- a/tests/baselines/reference/abstractPropertyNegative.js
+++ b/tests/baselines/reference/abstractPropertyNegative.js
@@ -59,7 +59,7 @@ var C = (function (_super) {
     function C() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.ro = "readonly please";
+        _this.ro = "readonly please";
     }
     Object.defineProperty(C.prototype, "concreteWithNoBody", {
         get: function () { },
@@ -80,7 +80,7 @@ var WrongTypePropertyImpl = (function (_super) {
     function WrongTypePropertyImpl() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.num = "nope, wrong";
+        _this.num = "nope, wrong";
     }
     return WrongTypePropertyImpl;
 }(WrongTypeProperty));
@@ -107,7 +107,7 @@ var WrongTypeAccessorImpl2 = (function (_super) {
     function WrongTypeAccessorImpl2() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.num = "nope, wrong";
+        _this.num = "nope, wrong";
     }
     return WrongTypeAccessorImpl2;
 }(WrongTypeAccessor));
diff --git a/tests/baselines/reference/accessOverriddenBaseClassMember1.js b/tests/baselines/reference/accessOverriddenBaseClassMember1.js
index d60f260a163..b4c269b1e3b 100644
--- a/tests/baselines/reference/accessOverriddenBaseClassMember1.js
+++ b/tests/baselines/reference/accessOverriddenBaseClassMember1.js
@@ -36,7 +36,7 @@ var ColoredPoint = (function (_super) {
     function ColoredPoint(x, y, color) {
         var _this;
         _this = _super.call(this, x, y) || this;
-        this.color = color;
+        _this.color = color;
     }
     ColoredPoint.prototype.toString = function () {
         return _super.prototype.toString.call(this) + " color=" + this.color;
diff --git a/tests/baselines/reference/aliasUsageInTypeArgumentOfExtendsClause.js b/tests/baselines/reference/aliasUsageInTypeArgumentOfExtendsClause.js
index 1893f6586ee..462390d28f7 100644
--- a/tests/baselines/reference/aliasUsageInTypeArgumentOfExtendsClause.js
+++ b/tests/baselines/reference/aliasUsageInTypeArgumentOfExtendsClause.js
@@ -67,7 +67,7 @@ var D = (function (_super) {
     function D() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.x = moduleA;
+        _this.x = moduleA;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/autolift4.js b/tests/baselines/reference/autolift4.js
index 85dd3725639..b6afd28d429 100644
--- a/tests/baselines/reference/autolift4.js
+++ b/tests/baselines/reference/autolift4.js
@@ -45,7 +45,7 @@ var Point3D = (function (_super) {
     function Point3D(x, y, z, m) {
         var _this;
         _this = _super.call(this, x, y) || this;
-        this.z = z;
+        _this.z = z;
     }
     Point3D.prototype.getDist = function () {
         return Math.sqrt(this.x * this.x + this.y * this.y + this.z * this.m);
diff --git a/tests/baselines/reference/baseCheck.js b/tests/baselines/reference/baseCheck.js
index 800742ff63b..c3a2731b45d 100644
--- a/tests/baselines/reference/baseCheck.js
+++ b/tests/baselines/reference/baseCheck.js
@@ -63,8 +63,8 @@ var D = (function (_super) {
     __extends(D, _super);
     function D(z) {
         var _this;
-        _this = _super.call(this, this.z) || this;
-        this.z = z;
+        _this = _super.call(this, _this.z) || this;
+        _this.z = z;
     }
     return D;
 }(C)); // too few params
@@ -72,8 +72,8 @@ var E = (function (_super) {
     __extends(E, _super);
     function E(z) {
         var _this;
-        _this = _super.call(this, 0, this.z) || this;
-        this.z = z;
+        _this = _super.call(this, 0, _this.z) || this;
+        _this.z = z;
     }
     return E;
 }(C));
@@ -81,8 +81,8 @@ var F = (function (_super) {
     __extends(F, _super);
     function F(z) {
         var _this;
-        _this = _super.call(this, "hello", this.z) || this;
-        this.z = z;
+        _this = _super.call(this, "hello", _this.z) || this;
+        _this.z = z;
     }
     return F;
 }(C)); // first param type
diff --git a/tests/baselines/reference/bases.js b/tests/baselines/reference/bases.js
index fcf1d7fe124..ff6a3262d45 100644
--- a/tests/baselines/reference/bases.js
+++ b/tests/baselines/reference/bases.js
@@ -37,7 +37,7 @@ var C = (function (_super) {
     __extends(C, _super);
     function C() {
         var _this;
-        this.x;
+        _this.x;
         any;
     }
     return C;
diff --git a/tests/baselines/reference/bestCommonTypeOfTuple2.js b/tests/baselines/reference/bestCommonTypeOfTuple2.js
index 36232ad04b1..34deb346cbd 100644
--- a/tests/baselines/reference/bestCommonTypeOfTuple2.js
+++ b/tests/baselines/reference/bestCommonTypeOfTuple2.js
@@ -62,7 +62,7 @@ var D1 = (function (_super) {
     function D1() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.i = "bar";
+        _this.i = "bar";
     }
     return D1;
 }(C1));
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing1.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing1.js
index dc70f3e8d08..35e00c36621 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing1.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing1.js
@@ -26,9 +26,9 @@ var Derived = (function (_super) {
     function Derived() {
         var _this;
         _this = _super.call(this) || this;
-        this;
-        this.x = 10;
-        var that = this;
+        _this;
+        _this.x = 10;
+        var that = _this;
     }
     return Derived;
 }(Based));
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing2.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing2.js
index f1fcdb48dae..b49c1aab774 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing2.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing2.js
@@ -25,10 +25,10 @@ var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
         var _this;
-        this.x = 100;
+        _this.x = 100;
         _this = _super.call(this) || this;
-        this.x = 10;
-        var that = this;
+        _this.x = 10;
+        var that = _this;
     }
     return Derived;
 }(Based));
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing3.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing3.js
index d2ede7d04b1..70600bb03a9 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing3.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing3.js
@@ -37,8 +37,8 @@ var Derived = (function (_super) {
             return innver;
         }());
         _this = _super.call(this) || this;
-        this.x = 10;
-        var that = this;
+        _this.x = 10;
+        var that = _this;
     }
     return Derived;
 }(Based));
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing4.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing4.js
index c6eddf4ef48..95e0062b087 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing4.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing4.js
@@ -45,8 +45,8 @@ var Derived = (function (_super) {
         })();
         _this = _super.call(this) || this;
         _this = _super.call(this) || this;
-        this.x = 10;
-        var that = this;
+        _this.x = 10;
+        var that = _this;
     }
     return Derived;
 }(Based));
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing5.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing5.js
index e58d55fd274..1c77b2e7c78 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing5.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing5.js
@@ -26,7 +26,7 @@ var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
         var _this;
-        _this = _super.call(this, this.x) || this;
+        _this = _super.call(this, _this.x) || this;
     }
     return Derived;
 }(Based));
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing8.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing8.js
index cf0da205d71..a280c0d6ca6 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing8.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing8.js
@@ -29,7 +29,7 @@ var Super = (function (_super) {
     __extends(Super, _super);
     function Super() {
         var _this;
-        var that = this;
+        var that = _this;
         _this = _super.call(this) || this;
     }
     return Super;
diff --git a/tests/baselines/reference/classConstructorAccessibility2.js b/tests/baselines/reference/classConstructorAccessibility2.js
index 95206681372..9d1ebdd9d9a 100644
--- a/tests/baselines/reference/classConstructorAccessibility2.js
+++ b/tests/baselines/reference/classConstructorAccessibility2.js
@@ -79,7 +79,7 @@ var DerivedA = (function (_super) {
     function DerivedA(x) {
         var _this;
         _this = _super.call(this, x) || this;
-        this.x = x;
+        _this.x = x;
     }
     DerivedA.prototype.createInstance = function () { new DerivedA(5); };
     DerivedA.prototype.createBaseInstance = function () { new BaseA(6); };
@@ -91,7 +91,7 @@ var DerivedB = (function (_super) {
     function DerivedB(x) {
         var _this;
         _this = _super.call(this, x) || this;
-        this.x = x;
+        _this.x = x;
     }
     DerivedB.prototype.createInstance = function () { new DerivedB(7); };
     DerivedB.prototype.createBaseInstance = function () { new BaseB(8); }; // ok
@@ -103,7 +103,7 @@ var DerivedC = (function (_super) {
     function DerivedC(x) {
         var _this;
         _this = _super.call(this, x) || this;
-        this.x = x;
+        _this.x = x;
     }
     DerivedC.prototype.createInstance = function () { new DerivedC(9); };
     DerivedC.prototype.createBaseInstance = function () { new BaseC(10); }; // error
diff --git a/tests/baselines/reference/classConstructorParametersAccessibility.js b/tests/baselines/reference/classConstructorParametersAccessibility.js
index 1f282ba7132..066c724b60f 100644
--- a/tests/baselines/reference/classConstructorParametersAccessibility.js
+++ b/tests/baselines/reference/classConstructorParametersAccessibility.js
@@ -61,7 +61,7 @@ var Derived = (function (_super) {
     function Derived(p) {
         var _this;
         _this = _super.call(this, p) || this;
-        this.p; // OK
+        _this.p; // OK
     }
     return Derived;
 }(C3));
diff --git a/tests/baselines/reference/classConstructorParametersAccessibility2.js b/tests/baselines/reference/classConstructorParametersAccessibility2.js
index 81ad696ddc8..b8050435171 100644
--- a/tests/baselines/reference/classConstructorParametersAccessibility2.js
+++ b/tests/baselines/reference/classConstructorParametersAccessibility2.js
@@ -61,7 +61,7 @@ var Derived = (function (_super) {
     function Derived(p) {
         var _this;
         _this = _super.call(this, p) || this;
-        this.p; // OK
+        _this.p; // OK
     }
     return Derived;
 }(C3));
diff --git a/tests/baselines/reference/classConstructorParametersAccessibility3.js b/tests/baselines/reference/classConstructorParametersAccessibility3.js
index 95509867cc5..9e0c0264fd9 100644
--- a/tests/baselines/reference/classConstructorParametersAccessibility3.js
+++ b/tests/baselines/reference/classConstructorParametersAccessibility3.js
@@ -30,8 +30,8 @@ var Derived = (function (_super) {
     function Derived(p) {
         var _this;
         _this = _super.call(this, p) || this;
-        this.p = p;
-        this.p; // OK
+        _this.p = p;
+        _this.p; // OK
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/classExpression3.js b/tests/baselines/reference/classExpression3.js
index b91d5413611..e0ba9c349e7 100644
--- a/tests/baselines/reference/classExpression3.js
+++ b/tests/baselines/reference/classExpression3.js
@@ -17,7 +17,7 @@ var C = (function (_super) {
     function class_1() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.c = 3;
+        _this.c = 3;
     }
     return class_1;
 }((function (_super) {
@@ -25,7 +25,7 @@ var C = (function (_super) {
     function class_2() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.b = 2;
+        _this.b = 2;
     }
     return class_2;
 }((function () {
diff --git a/tests/baselines/reference/classExtendingClassLikeType.js b/tests/baselines/reference/classExtendingClassLikeType.js
index 031253a19ad..2d91befc172 100644
--- a/tests/baselines/reference/classExtendingClassLikeType.js
+++ b/tests/baselines/reference/classExtendingClassLikeType.js
@@ -78,8 +78,8 @@ var D1 = (function (_super) {
     function D1() {
         var _this;
         _this = _super.call(this, "abc", "def") || this;
-        this.x = "x";
-        this.y = "y";
+        _this.x = "x";
+        _this.y = "y";
     }
     return D1;
 }(getBase()));
@@ -89,8 +89,8 @@ var D2 = (function (_super) {
         var _this;
         _this = _super.call(this, 10) || this;
         _this = _super.call(this, 10, 20) || this;
-        this.x = 1;
-        this.y = 2;
+        _this.x = 1;
+        _this.y = 2;
     }
     return D2;
 }(getBase()));
@@ -99,8 +99,8 @@ var D3 = (function (_super) {
     function D3() {
         var _this;
         _this = _super.call(this, "abc", 42) || this;
-        this.x = "x";
-        this.y = 2;
+        _this.x = "x";
+        _this.y = 2;
     }
     return D3;
 }(getBase()));
diff --git a/tests/baselines/reference/classSideInheritance3.js b/tests/baselines/reference/classSideInheritance3.js
index d9e4c3f1482..4751e0e8d6e 100644
--- a/tests/baselines/reference/classSideInheritance3.js
+++ b/tests/baselines/reference/classSideInheritance3.js
@@ -35,7 +35,7 @@ var B = (function (_super) {
     function B(x, data) {
         var _this;
         _this = _super.call(this, x) || this;
-        this.data = data;
+        _this.data = data;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/classUpdateTests.js b/tests/baselines/reference/classUpdateTests.js
index 7b13fa1bf4c..d334e1c7f66 100644
--- a/tests/baselines/reference/classUpdateTests.js
+++ b/tests/baselines/reference/classUpdateTests.js
@@ -159,7 +159,7 @@ var E = (function (_super) {
     function E() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.p1 = 0;
+        _this.p1 = 0;
     }
     return E;
 }(D));
@@ -175,7 +175,7 @@ var G = (function (_super) {
     function G() {
         var _this;
         _this = _super.call(this) || this;
-        this.p1 = 0;
+        _this.p1 = 0;
     } // NO ERROR
     return G;
 }(D));
@@ -198,7 +198,7 @@ var J = (function (_super) {
     function J(p1) {
         var _this;
         _this = _super.call(this) || this; // NO ERROR
-        this.p1 = p1;
+        _this.p1 = p1;
     }
     return J;
 }(G));
@@ -206,7 +206,7 @@ var K = (function (_super) {
     __extends(K, _super);
     function K(p1) {
         var _this;
-        this.p1 = p1;
+        _this.p1 = p1;
         var i = 0;
         _this = _super.call(this) || this;
     }
@@ -217,7 +217,7 @@ var L = (function (_super) {
     function L(p1) {
         var _this;
         _this = _super.call(this) || this; // NO ERROR
-        this.p1 = p1;
+        _this.p1 = p1;
     }
     return L;
 }(G));
@@ -225,7 +225,7 @@ var M = (function (_super) {
     __extends(M, _super);
     function M(p1) {
         var _this;
-        this.p1 = p1;
+        _this.p1 = p1;
         var i = 0;
         _this = _super.call(this) || this;
     }
diff --git a/tests/baselines/reference/collisionSuperAndLocalFunctionInProperty.js b/tests/baselines/reference/collisionSuperAndLocalFunctionInProperty.js
index da4175fe5c7..e3d834dd1d4 100644
--- a/tests/baselines/reference/collisionSuperAndLocalFunctionInProperty.js
+++ b/tests/baselines/reference/collisionSuperAndLocalFunctionInProperty.js
@@ -42,7 +42,7 @@ var b = (function (_super) {
     function b() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.prop2 = {
+        _this.prop2 = {
             doStuff: function () {
                 function _super() {
                 }
diff --git a/tests/baselines/reference/collisionSuperAndLocalVarInProperty.js b/tests/baselines/reference/collisionSuperAndLocalVarInProperty.js
index 598bb5b6e85..e7cb0e613cc 100644
--- a/tests/baselines/reference/collisionSuperAndLocalVarInProperty.js
+++ b/tests/baselines/reference/collisionSuperAndLocalVarInProperty.js
@@ -40,12 +40,12 @@ var b = (function (_super) {
     function b() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.prop2 = {
+        _this.prop2 = {
             doStuff: function () {
                 var _super = 10; // Should be error 
             }
         };
-        this._super = 10; // No error
+        _this._super = 10; // No error
     }
     return b;
 }(Foo));
diff --git a/tests/baselines/reference/collisionSuperAndParameter.js b/tests/baselines/reference/collisionSuperAndParameter.js
index 9909ca512ce..a60889888d6 100644
--- a/tests/baselines/reference/collisionSuperAndParameter.js
+++ b/tests/baselines/reference/collisionSuperAndParameter.js
@@ -96,7 +96,7 @@ var Foo2 = (function (_super) {
     function Foo2(_super) {
         var _this;
         _this = _super.call(this) || this;
-        this.prop4 = {
+        _this.prop4 = {
             doStuff: function (_super) {
             }
         };
diff --git a/tests/baselines/reference/collisionSuperAndPropertyNameAsConstuctorParameter.js b/tests/baselines/reference/collisionSuperAndPropertyNameAsConstuctorParameter.js
index 6a8dd340a20..696f439a4b1 100644
--- a/tests/baselines/reference/collisionSuperAndPropertyNameAsConstuctorParameter.js
+++ b/tests/baselines/reference/collisionSuperAndPropertyNameAsConstuctorParameter.js
@@ -54,7 +54,7 @@ var b2 = (function (_super) {
     function b2(_super) {
         var _this;
         _this = _super.call(this) || this;
-        this._super = _super;
+        _this._super = _super;
     }
     return b2;
 }(a));
@@ -71,7 +71,7 @@ var b4 = (function (_super) {
     function b4(_super) {
         var _this;
         _this = _super.call(this) || this;
-        this._super = _super;
+        _this._super = _super;
     }
     return b4;
 }(a));
diff --git a/tests/baselines/reference/computedPropertyNames30_ES5.js b/tests/baselines/reference/computedPropertyNames30_ES5.js
index c31d873ffb9..9fbe5f380ca 100644
--- a/tests/baselines/reference/computedPropertyNames30_ES5.js
+++ b/tests/baselines/reference/computedPropertyNames30_ES5.js
@@ -36,7 +36,7 @@ var C = (function (_super) {
                 // Ideally, we would capture this. But the reference is
                 // illegal, and not capturing this is consistent with
                 //treatment of other similar violations.
-                _a[(_this = _super.call(_this) || _this, "prop")] = function () { },
+                _a[(_this = _super.call(this) || this, "prop")] = function () { },
                 _a);
             var _a;
         });
diff --git a/tests/baselines/reference/constructorArgs.js b/tests/baselines/reference/constructorArgs.js
index 3345708ddaa..2c2838c97f9 100644
--- a/tests/baselines/reference/constructorArgs.js
+++ b/tests/baselines/reference/constructorArgs.js
@@ -31,7 +31,7 @@ var Sub = (function (_super) {
     function Sub(options) {
         var _this;
         _this = _super.call(this, options.value) || this;
-        this.options = options;
+        _this.options = options;
     }
     return Sub;
 }(Super));
diff --git a/tests/baselines/reference/declFileGenericType2.js b/tests/baselines/reference/declFileGenericType2.js
index 4ccc090f4f2..50280b589b3 100644
--- a/tests/baselines/reference/declFileGenericType2.js
+++ b/tests/baselines/reference/declFileGenericType2.js
@@ -81,7 +81,7 @@ var templa;
                     function AbstractCompositeElementController() {
                         var _this;
                         _this = _super.call(this) || this;
-                        this._controllers = [];
+                        _this._controllers = [];
                     }
                     return AbstractCompositeElementController;
                 }(templa.dom.mvc.AbstractElementController));
diff --git a/tests/baselines/reference/derivedClassConstructorWithoutSuperCall.js b/tests/baselines/reference/derivedClassConstructorWithoutSuperCall.js
index 75901c708b3..58903b2ba57 100644
--- a/tests/baselines/reference/derivedClassConstructorWithoutSuperCall.js
+++ b/tests/baselines/reference/derivedClassConstructorWithoutSuperCall.js
@@ -60,7 +60,7 @@ var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
         var _this;
-        var r2 = function () { return _this = _super.call(_this) || _this; }; // error for misplaced super call (nested function)
+        var r2 = function () { return _this = _super.call(this) || this; }; // error for misplaced super call (nested function)
     }
     return Derived2;
 }(Base2));
diff --git a/tests/baselines/reference/derivedClassParameterProperties.js b/tests/baselines/reference/derivedClassParameterProperties.js
index f7afd6529c0..658e56fb098 100644
--- a/tests/baselines/reference/derivedClassParameterProperties.js
+++ b/tests/baselines/reference/derivedClassParameterProperties.js
@@ -119,7 +119,7 @@ var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2(y) {
         var _this;
-        this.y = y;
+        _this.y = y;
         var a = 1;
         _this = _super.call(this) || this; // error
     }
@@ -130,7 +130,7 @@ var Derived3 = (function (_super) {
     function Derived3(y) {
         var _this;
         _this = _super.call(this) || this; // ok
-        this.y = y;
+        _this.y = y;
         var a = 1;
     }
     return Derived3;
@@ -139,7 +139,7 @@ var Derived4 = (function (_super) {
     __extends(Derived4, _super);
     function Derived4(y) {
         var _this;
-        this.a = 1;
+        _this.a = 1;
         var b = 2;
         _this = _super.call(this) || this; // error
     }
@@ -150,7 +150,7 @@ var Derived5 = (function (_super) {
     function Derived5(y) {
         var _this;
         _this = _super.call(this) || this; // ok
-        this.a = 1;
+        _this.a = 1;
         var b = 2;
     }
     return Derived5;
@@ -159,7 +159,7 @@ var Derived6 = (function (_super) {
     __extends(Derived6, _super);
     function Derived6(y) {
         var _this;
-        this.a = 1;
+        _this.a = 1;
         var b = 2;
         _this = _super.call(this) || this; // error: "super" has to be called before "this" accessing
     }
@@ -169,9 +169,9 @@ var Derived7 = (function (_super) {
     __extends(Derived7, _super);
     function Derived7(y) {
         var _this;
-        this.a = 1;
-        this.a = 3;
-        this.b = 3;
+        _this.a = 1;
+        _this.a = 3;
+        _this.b = 3;
         _this = _super.call(this) || this; // error
     }
     return Derived7;
@@ -181,9 +181,9 @@ var Derived8 = (function (_super) {
     function Derived8(y) {
         var _this;
         _this = _super.call(this) || this; // ok
-        this.a = 1;
-        this.a = 3;
-        this.b = 3;
+        _this.a = 1;
+        _this.a = 3;
+        _this.b = 3;
     }
     return Derived8;
 }(Base));
@@ -197,9 +197,9 @@ var Derived9 = (function (_super) {
     __extends(Derived9, _super);
     function Derived9(y) {
         var _this;
-        this.a = 1;
-        this.a = 3;
-        this.b = 3;
+        _this.a = 1;
+        _this.a = 3;
+        _this.b = 3;
         _this = _super.call(this) || this; // error
     }
     return Derived9;
@@ -209,9 +209,9 @@ var Derived10 = (function (_super) {
     function Derived10(y) {
         var _this;
         _this = _super.call(this) || this; // ok
-        this.a = 1;
-        this.a = 3;
-        this.b = 3;
+        _this.a = 1;
+        _this.a = 3;
+        _this.b = 3;
     }
     return Derived10;
 }(Base2));
diff --git a/tests/baselines/reference/derivedClassSuperCallsInNonConstructorMembers.js b/tests/baselines/reference/derivedClassSuperCallsInNonConstructorMembers.js
index ad2dc22debf..6b06204b8e9 100644
--- a/tests/baselines/reference/derivedClassSuperCallsInNonConstructorMembers.js
+++ b/tests/baselines/reference/derivedClassSuperCallsInNonConstructorMembers.js
@@ -48,7 +48,7 @@ var Derived = (function (_super) {
     function Derived() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.a = _this = _super.call(this) || this;
+        _this.a = _this = _super.call(this) || this;
     }
     Derived.prototype.b = function () {
         _this = _super.call(this) || this;
diff --git a/tests/baselines/reference/derivedClassSuperCallsWithThisArg.js b/tests/baselines/reference/derivedClassSuperCallsWithThisArg.js
index a464970fe50..e73d0041206 100644
--- a/tests/baselines/reference/derivedClassSuperCallsWithThisArg.js
+++ b/tests/baselines/reference/derivedClassSuperCallsWithThisArg.js
@@ -43,7 +43,7 @@ var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
         var _this;
-        _this = _super.call(this, this) || this; // ok
+        _this = _super.call(this, _this) || this; // ok
     }
     return Derived;
 }(Base));
@@ -51,8 +51,8 @@ var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2(a) {
         var _this;
-        _this = _super.call(this, this) || this; // error
-        this.a = a;
+        _this = _super.call(this, _this) || this; // error
+        _this.a = a;
     }
     return Derived2;
 }(Base));
@@ -61,7 +61,7 @@ var Derived3 = (function (_super) {
     function Derived3(a) {
         var _this;
         _this = _super.call(this, function () { return _this; }) || this; // error
-        this.a = a;
+        _this.a = a;
     }
     return Derived3;
 }(Base));
@@ -70,7 +70,7 @@ var Derived4 = (function (_super) {
     function Derived4(a) {
         var _this;
         _this = _super.call(this, function () { return this; }) || this; // ok
-        this.a = a;
+        _this.a = a;
     }
     return Derived4;
 }(Base));
diff --git a/tests/baselines/reference/derivedClassWithoutExplicitConstructor.js b/tests/baselines/reference/derivedClassWithoutExplicitConstructor.js
index 84028f1d3f2..cc260f09499 100644
--- a/tests/baselines/reference/derivedClassWithoutExplicitConstructor.js
+++ b/tests/baselines/reference/derivedClassWithoutExplicitConstructor.js
@@ -43,8 +43,8 @@ var Derived = (function (_super) {
     function Derived() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.x = 1;
-        this.y = 'hello';
+        _this.x = 1;
+        _this.y = 'hello';
     }
     return Derived;
 }(Base));
@@ -61,8 +61,8 @@ var D = (function (_super) {
     function D() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.x = 2;
-        this.y = null;
+        _this.x = 2;
+        _this.y = null;
     }
     return D;
 }(Base2));
diff --git a/tests/baselines/reference/derivedClassWithoutExplicitConstructor2.js b/tests/baselines/reference/derivedClassWithoutExplicitConstructor2.js
index 6c3ce90d6f0..d3711ec27c0 100644
--- a/tests/baselines/reference/derivedClassWithoutExplicitConstructor2.js
+++ b/tests/baselines/reference/derivedClassWithoutExplicitConstructor2.js
@@ -51,8 +51,8 @@ var Derived = (function (_super) {
     function Derived() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.x = 1;
-        this.y = 'hello';
+        _this.x = 1;
+        _this.y = 'hello';
     }
     return Derived;
 }(Base));
@@ -71,8 +71,8 @@ var D = (function (_super) {
     function D() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.x = 2;
-        this.y = null;
+        _this.x = 2;
+        _this.y = null;
     }
     return D;
 }(Base2));
diff --git a/tests/baselines/reference/derivedClassWithoutExplicitConstructor3.js b/tests/baselines/reference/derivedClassWithoutExplicitConstructor3.js
index 295fbac60e1..14f9fdf88af 100644
--- a/tests/baselines/reference/derivedClassWithoutExplicitConstructor3.js
+++ b/tests/baselines/reference/derivedClassWithoutExplicitConstructor3.js
@@ -65,8 +65,8 @@ var Derived = (function (_super) {
     function Derived(y, z) {
         var _this;
         _this = _super.call(this, 2) || this;
-        this.b = '';
-        this.b = y;
+        _this.b = '';
+        _this.b = y;
     }
     return Derived;
 }(Base));
@@ -75,8 +75,8 @@ var Derived2 = (function (_super) {
     function Derived2() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.x = 1;
-        this.y = 'hello';
+        _this.x = 1;
+        _this.y = 'hello';
     }
     return Derived2;
 }(Derived));
@@ -94,8 +94,8 @@ var D = (function (_super) {
     function D(y, z) {
         var _this;
         _this = _super.call(this, 2) || this;
-        this.b = null;
-        this.b = y;
+        _this.b = null;
+        _this.b = y;
     }
     return D;
 }(Base));
@@ -104,8 +104,8 @@ var D2 = (function (_super) {
     function D2() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.x = 2;
-        this.y = null;
+        _this.x = 2;
+        _this.y = null;
     }
     return D2;
 }(D));
diff --git a/tests/baselines/reference/emitSuperCallBeforeEmitParameterPropertyDeclaration1.js b/tests/baselines/reference/emitSuperCallBeforeEmitParameterPropertyDeclaration1.js
index 4e07d5c8655..60fa8e32c1e 100644
--- a/tests/baselines/reference/emitSuperCallBeforeEmitParameterPropertyDeclaration1.js
+++ b/tests/baselines/reference/emitSuperCallBeforeEmitParameterPropertyDeclaration1.js
@@ -32,7 +32,7 @@ var B = (function (_super) {
         "use strict";
         'someStringForEgngInject';
         _this = _super.call(this) || this;
-        this.x = x;
+        _this.x = x;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclaration1.js b/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclaration1.js
index b6eabb2a418..abef8394924 100644
--- a/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclaration1.js
+++ b/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclaration1.js
@@ -34,7 +34,7 @@ var B = (function (_super) {
         "use strict";
         'someStringForEgngInject';
         _this = _super.call(this) || this;
-        this.blub = 12;
+        _this.blub = 12;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclarationAndParameterPropertyDeclaration1.js b/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclarationAndParameterPropertyDeclaration1.js
index 0e866e98f46..0f36d9d9115 100644
--- a/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclarationAndParameterPropertyDeclaration1.js
+++ b/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclarationAndParameterPropertyDeclaration1.js
@@ -32,8 +32,8 @@ var B = (function (_super) {
         "use strict";
         'someStringForEgngInject';
         _this = _super.call(this) || this;
-        this.x = x;
-        this.blah = 2;
+        _this.x = x;
+        _this.blah = 2;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/errorSuperCalls.js b/tests/baselines/reference/errorSuperCalls.js
index 765fdf083b5..4f54781deb9 100644
--- a/tests/baselines/reference/errorSuperCalls.js
+++ b/tests/baselines/reference/errorSuperCalls.js
@@ -133,7 +133,7 @@ var Derived = (function (_super) {
     //super call with type arguments 
     function Derived() {
         var _this;
-        _super.prototype..call(this);
+        _super.prototype..call(_this);
         _this = _super.call(this) || this;
     }
     return Derived;
@@ -149,7 +149,7 @@ var OtherDerived = (function (_super) {
         var _this;
         _this = _super.apply(this, arguments) || this;
         //super call in class member initializer of derived type
-        this.t = _this = _super.call(this) || this;
+        _this.t = _this = _super.call(this) || this;
     }
     OtherDerived.prototype.fn = function () {
         //super call in class member function of derived type
diff --git a/tests/baselines/reference/es6ClassTest.js b/tests/baselines/reference/es6ClassTest.js
index 0a6323630fb..4b2cb2c51b5 100644
--- a/tests/baselines/reference/es6ClassTest.js
+++ b/tests/baselines/reference/es6ClassTest.js
@@ -105,12 +105,12 @@ var Foo = (function (_super) {
         var _this;
         if (z === void 0) { z = 0; }
         _this = _super.call(this, x) || this;
-        this.y = y;
-        this.z = z;
-        this.gar = 0;
-        this.zoo = "zoo";
-        this.x = x;
-        this.gar = 5;
+        _this.y = y;
+        _this.z = z;
+        _this.gar = 0;
+        _this.zoo = "zoo";
+        _this.x = x;
+        _this.gar = 5;
     }
     Foo.prototype.bar = function () { return 0; };
     Foo.prototype.boo = function (x) { return x; };
diff --git a/tests/baselines/reference/genericRecursiveImplicitConstructorErrors3.js b/tests/baselines/reference/genericRecursiveImplicitConstructorErrors3.js
index 226fede58b6..49109e1aa5a 100644
--- a/tests/baselines/reference/genericRecursiveImplicitConstructorErrors3.js
+++ b/tests/baselines/reference/genericRecursiveImplicitConstructorErrors3.js
@@ -61,7 +61,7 @@ var TypeScript;
         function PullTypeSymbol() {
             var _this;
             _this = _super.apply(this, arguments) || this;
-            this._elementType = null;
+            _this._elementType = null;
         }
         PullTypeSymbol.prototype.toString = function (scopeSymbol, useConstraintInName) {
             var s = this.getScopedNameEx(scopeSymbol, useConstraintInName).toString();
diff --git a/tests/baselines/reference/illegalSuperCallsInConstructor.js b/tests/baselines/reference/illegalSuperCallsInConstructor.js
index e27a9789cb1..77f0a0a2b6b 100644
--- a/tests/baselines/reference/illegalSuperCallsInConstructor.js
+++ b/tests/baselines/reference/illegalSuperCallsInConstructor.js
@@ -35,8 +35,8 @@ var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
         var _this;
-        var r2 = function () { return _this = _super.call(_this) || _this; };
-        var r3 = function () { _this = _super.call(_this) || _this; };
+        var r2 = function () { return _this = _super.call(this) || this; };
+        var r3 = function () { _this = _super.call(this) || this; };
         var r4 = function () { _this = _super.call(this) || this; };
         var r5 = {
             get foo() {
diff --git a/tests/baselines/reference/interfaceExtendsClassWithPrivate2.js b/tests/baselines/reference/interfaceExtendsClassWithPrivate2.js
index 6f35c3f0e40..3f205640f59 100644
--- a/tests/baselines/reference/interfaceExtendsClassWithPrivate2.js
+++ b/tests/baselines/reference/interfaceExtendsClassWithPrivate2.js
@@ -41,8 +41,8 @@ var D = (function (_super) {
     function D() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.x = 2;
-        this.y = 3;
+        _this.x = 2;
+        _this.y = 3;
     }
     D.prototype.foo = function (x) { return x; };
     D.prototype.other = function (x) { return x; };
@@ -54,7 +54,7 @@ var D2 = (function (_super) {
     function D2() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.x = "";
+        _this.x = "";
     }
     D2.prototype.foo = function (x) { return x; };
     D2.prototype.other = function (x) { return x; };
diff --git a/tests/baselines/reference/objectCreationOfElementAccessExpression.js b/tests/baselines/reference/objectCreationOfElementAccessExpression.js
index ddfbce8fc12..9543082fbd1 100644
--- a/tests/baselines/reference/objectCreationOfElementAccessExpression.js
+++ b/tests/baselines/reference/objectCreationOfElementAccessExpression.js
@@ -83,7 +83,7 @@ var MonsterFood = (function (_super) {
     function MonsterFood(name, flavor) {
         var _this;
         _this = _super.call(this, name) || this;
-        this.flavor = flavor;
+        _this.flavor = flavor;
     }
     return MonsterFood;
 }(Food));
@@ -92,7 +92,7 @@ var IceCream = (function (_super) {
     function IceCream(flavor) {
         var _this;
         _this = _super.call(this, "Ice Cream", flavor) || this;
-        this.flavor = flavor;
+        _this.flavor = flavor;
     }
     return IceCream;
 }(MonsterFood));
@@ -101,8 +101,8 @@ var Cookie = (function (_super) {
     function Cookie(flavor, isGlutenFree) {
         var _this;
         _this = _super.call(this, "Cookie", flavor) || this;
-        this.flavor = flavor;
-        this.isGlutenFree = isGlutenFree;
+        _this.flavor = flavor;
+        _this.isGlutenFree = isGlutenFree;
     }
     return Cookie;
 }(MonsterFood));
@@ -111,7 +111,7 @@ var PetFood = (function (_super) {
     function PetFood(name, whereToBuy) {
         var _this;
         _this = _super.call(this, name) || this;
-        this.whereToBuy = whereToBuy;
+        _this.whereToBuy = whereToBuy;
     }
     return PetFood;
 }(Food));
@@ -120,7 +120,7 @@ var ExpensiveOrganicDogFood = (function (_super) {
     function ExpensiveOrganicDogFood(whereToBuy) {
         var _this;
         _this = _super.call(this, "Origen", whereToBuy) || this;
-        this.whereToBuy = whereToBuy;
+        _this.whereToBuy = whereToBuy;
     }
     return ExpensiveOrganicDogFood;
 }(PetFood));
@@ -129,8 +129,8 @@ var ExpensiveOrganicCatFood = (function (_super) {
     function ExpensiveOrganicCatFood(whereToBuy, containsFish) {
         var _this;
         _this = _super.call(this, "Nature's Logic", whereToBuy) || this;
-        this.whereToBuy = whereToBuy;
-        this.containsFish = containsFish;
+        _this.whereToBuy = whereToBuy;
+        _this.containsFish = containsFish;
     }
     return ExpensiveOrganicCatFood;
 }(PetFood));
diff --git a/tests/baselines/reference/optionalMethods.js b/tests/baselines/reference/optionalMethods.js
index 408f73b6533..1885c419fef 100644
--- a/tests/baselines/reference/optionalMethods.js
+++ b/tests/baselines/reference/optionalMethods.js
@@ -111,7 +111,7 @@ var Derived = (function (_super) {
     function Derived() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.a = 1;
+        _this.a = 1;
     }
     Derived.prototype.f = function () { return 1; };
     return Derived;
diff --git a/tests/baselines/reference/optionalParameterProperty.js b/tests/baselines/reference/optionalParameterProperty.js
index b23da97c790..44eb2a7aa56 100644
--- a/tests/baselines/reference/optionalParameterProperty.js
+++ b/tests/baselines/reference/optionalParameterProperty.js
@@ -27,7 +27,7 @@ var D = (function (_super) {
     function D(p) {
         var _this;
         _this = _super.call(this) || this;
-        this.p = p;
+        _this.p = p;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/overloadOnConstConstraintChecks4.js b/tests/baselines/reference/overloadOnConstConstraintChecks4.js
index 6a750612395..22bacbdb0b4 100644
--- a/tests/baselines/reference/overloadOnConstConstraintChecks4.js
+++ b/tests/baselines/reference/overloadOnConstConstraintChecks4.js
@@ -29,7 +29,7 @@ var A = (function (_super) {
     function A() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.x = 1;
+        _this.x = 1;
     }
     return A;
 }(Z));
diff --git a/tests/baselines/reference/parserAstSpans1.js b/tests/baselines/reference/parserAstSpans1.js
index 6e6a423fe90..365e640c150 100644
--- a/tests/baselines/reference/parserAstSpans1.js
+++ b/tests/baselines/reference/parserAstSpans1.js
@@ -320,7 +320,7 @@ var c3 = (function (_super) {
     function c3() {
         var _this;
         _this = _super.call(this, 10) || this;
-        this.p1 = _super.prototype.c2_p1;
+        _this.p1 = _super.prototype.c2_p1;
     }
     /** c3 f1*/
     c3.prototype.f1 = function () {
@@ -408,7 +408,7 @@ var c6 = (function (_super) {
     function c6() {
         var _this;
         _this = _super.call(this) || this;
-        this.d = _super.prototype.b;
+        _this.d = _super.prototype.b;
     }
     return c6;
 }(c5));
diff --git a/tests/baselines/reference/parserRealSource10.js b/tests/baselines/reference/parserRealSource10.js
index 429a388c894..c9f011704d0 100644
--- a/tests/baselines/reference/parserRealSource10.js
+++ b/tests/baselines/reference/parserRealSource10.js
@@ -828,8 +828,8 @@ var TypeScript;
         function NumberLiteralToken(value, hasEmptyFraction) {
             var _this;
             _this = _super.call(this, TokenID.NumberLiteral) || this;
-            this.value = value;
-            this.hasEmptyFraction = hasEmptyFraction;
+            _this.value = value;
+            _this.hasEmptyFraction = hasEmptyFraction;
         }
         NumberLiteralToken.prototype.getText = function () {
             return this.hasEmptyFraction ? this.value.toString() + ".0" : this.value.toString();
@@ -845,7 +845,7 @@ var TypeScript;
         function StringLiteralToken(value) {
             var _this;
             _this = _super.call(this, TokenID.StringLiteral) || this;
-            this.value = value;
+            _this.value = value;
         }
         StringLiteralToken.prototype.getText = function () {
             return this.value;
@@ -861,8 +861,8 @@ var TypeScript;
         function IdentifierToken(value, hasEscapeSequence) {
             var _this;
             _this = _super.call(this, TokenID.Identifier) || this;
-            this.value = value;
-            this.hasEscapeSequence = hasEscapeSequence;
+            _this.value = value;
+            _this.hasEscapeSequence = hasEscapeSequence;
         }
         IdentifierToken.prototype.getText = function () {
             return this.value;
@@ -878,7 +878,7 @@ var TypeScript;
         function WhitespaceToken(tokenId, value) {
             var _this;
             _this = _super.call(this, tokenId) || this;
-            this.value = value;
+            _this.value = value;
         }
         WhitespaceToken.prototype.getText = function () {
             return this.value;
@@ -894,11 +894,11 @@ var TypeScript;
         function CommentToken(tokenID, value, isBlock, startPos, line, endsLine) {
             var _this;
             _this = _super.call(this, tokenID) || this;
-            this.value = value;
-            this.isBlock = isBlock;
-            this.startPos = startPos;
-            this.line = line;
-            this.endsLine = endsLine;
+            _this.value = value;
+            _this.isBlock = isBlock;
+            _this.startPos = startPos;
+            _this.line = line;
+            _this.endsLine = endsLine;
         }
         CommentToken.prototype.getText = function () {
             return this.value;
@@ -914,7 +914,7 @@ var TypeScript;
         function RegularExpressionLiteralToken(regex) {
             var _this;
             _this = _super.call(this, TokenID.RegularExpressionLiteral) || this;
-            this.regex = regex;
+            _this.regex = regex;
         }
         RegularExpressionLiteralToken.prototype.getText = function () {
             return this.regex.toString();
diff --git a/tests/baselines/reference/parserRealSource11.js b/tests/baselines/reference/parserRealSource11.js
index 4be1ed20767..054608e9d19 100644
--- a/tests/baselines/reference/parserRealSource11.js
+++ b/tests/baselines/reference/parserRealSource11.js
@@ -2388,14 +2388,14 @@ var TypeScript;
         function AST(nodeType) {
             var _this;
             _this = _super.call(this) || this;
-            this.nodeType = nodeType;
-            this.type = null;
-            this.flags = ASTFlags.Writeable;
+            _this.nodeType = nodeType;
+            _this.type = null;
+            _this.flags = ASTFlags.Writeable;
             // REVIEW: for diagnostic purposes
-            this.passCreated = CompilerDiagnostics.analysisPass;
-            this.preComments = null;
-            this.postComments = null;
-            this.isParenthesized = false;
+            _this.passCreated = CompilerDiagnostics.analysisPass;
+            _this.preComments = null;
+            _this.postComments = null;
+            _this.isParenthesized = false;
         }
         AST.prototype.isExpression = function () { return false; };
         AST.prototype.isStatementOrExpression = function () { return false; };
@@ -2545,8 +2545,8 @@ var TypeScript;
         function IncompleteAST(min, lim) {
             var _this;
             _this = _super.call(this, NodeType.Error) || this;
-            this.minChar = min;
-            this.limChar = lim;
+            _this.minChar = min;
+            _this.limChar = lim;
         }
         return IncompleteAST;
     }(AST));
@@ -2556,8 +2556,8 @@ var TypeScript;
         function ASTList() {
             var _this;
             _this = _super.call(this, NodeType.List) || this;
-            this.enclosingScope = null;
-            this.members = new AST[];
+            _this.enclosingScope = null;
+            _this.members = new AST[];
         }
         ASTList.prototype.addToControlFlow = function (context) {
             var len = this.members.length;
@@ -2624,11 +2624,11 @@ var TypeScript;
         function Identifier(actualText, hasEscapeSequence) {
             var _this;
             _this = _super.call(this, NodeType.Name) || this;
-            this.actualText = actualText;
-            this.hasEscapeSequence = hasEscapeSequence;
-            this.sym = null;
-            this.cloId = -1;
-            this.setText(actualText, hasEscapeSequence);
+            _this.actualText = actualText;
+            _this.hasEscapeSequence = hasEscapeSequence;
+            _this.sym = null;
+            _this.cloId = -1;
+            _this.setText(actualText, hasEscapeSequence);
         }
         Identifier.prototype.setText = function (actualText, hasEscapeSequence) {
             this.actualText = actualText;
@@ -2684,7 +2684,7 @@ var TypeScript;
         function Label(id) {
             var _this;
             _this = _super.call(this, NodeType.Label) || this;
-            this.id = id;
+            _this.id = id;
         }
         Label.prototype.printLabel = function () { return this.id.actualText + ":"; };
         Label.prototype.typeCheck = function (typeFlow) {
@@ -2720,9 +2720,9 @@ var TypeScript;
         function UnaryExpression(nodeType, operand) {
             var _this;
             _this = _super.call(this, nodeType) || this;
-            this.operand = operand;
-            this.targetType = null; // Target type for an object literal (null if no target type)
-            this.castTerm = null;
+            _this.operand = operand;
+            _this.targetType = null; // Target type for an object literal (null if no target type)
+            _this.castTerm = null;
         }
         UnaryExpression.prototype.addToControlFlow = function (context) {
             _super.prototype.addToControlFlow.call(this, context);
@@ -2865,10 +2865,10 @@ var TypeScript;
         function CallExpression(nodeType, target, arguments) {
             var _this;
             _this = _super.call(this, nodeType) || this;
-            this.target = target;
-            this.arguments = arguments;
-            this.signature = null;
-            this.minChar = this.target.minChar;
+            _this.target = target;
+            _this.arguments = arguments;
+            _this.signature = null;
+            _this.minChar = _this.target.minChar;
         }
         CallExpression.prototype.typeCheck = function (typeFlow) {
             if (this.nodeType == NodeType.New) {
@@ -2898,8 +2898,8 @@ var TypeScript;
         function BinaryExpression(nodeType, operand1, operand2) {
             var _this;
             _this = _super.call(this, nodeType) || this;
-            this.operand1 = operand1;
-            this.operand2 = operand2;
+            _this.operand1 = operand1;
+            _this.operand2 = operand2;
         }
         BinaryExpression.prototype.typeCheck = function (typeFlow) {
             switch (this.nodeType) {
@@ -3051,9 +3051,9 @@ var TypeScript;
         function ConditionalExpression(operand1, operand2, operand3) {
             var _this;
             _this = _super.call(this, NodeType.ConditionalExpression) || this;
-            this.operand1 = operand1;
-            this.operand2 = operand2;
-            this.operand3 = operand3;
+            _this.operand1 = operand1;
+            _this.operand2 = operand2;
+            _this.operand3 = operand3;
         }
         ConditionalExpression.prototype.typeCheck = function (typeFlow) {
             return typeFlow.typeCheckQMark(this);
@@ -3077,9 +3077,9 @@ var TypeScript;
         function NumberLiteral(value, hasEmptyFraction) {
             var _this;
             _this = _super.call(this, NodeType.NumberLit) || this;
-            this.value = value;
-            this.hasEmptyFraction = hasEmptyFraction;
-            this.isNegativeZero = false;
+            _this.value = value;
+            _this.hasEmptyFraction = hasEmptyFraction;
+            _this.isNegativeZero = false;
         }
         NumberLiteral.prototype.typeCheck = function (typeFlow) {
             this.type = typeFlow.doubleType;
@@ -3119,7 +3119,7 @@ var TypeScript;
         function RegexLiteral(regex) {
             var _this;
             _this = _super.call(this, NodeType.Regex) || this;
-            this.regex = regex;
+            _this.regex = regex;
         }
         RegexLiteral.prototype.typeCheck = function (typeFlow) {
             this.type = typeFlow.regexType;
@@ -3140,7 +3140,7 @@ var TypeScript;
         function StringLiteral(text) {
             var _this;
             _this = _super.call(this, NodeType.QString) || this;
-            this.text = text;
+            _this.text = text;
         }
         StringLiteral.prototype.emit = function (emitter, tokenId, startLine) {
             emitter.emitParensAndCommentsInPlace(this, true);
@@ -3176,10 +3176,10 @@ var TypeScript;
         function ImportDeclaration(id, alias) {
             var _this;
             _this = _super.call(this, NodeType.ImportDeclaration) || this;
-            this.id = id;
-            this.alias = alias;
-            this.varFlags = VarFlags.None;
-            this.isDynamicImport = false;
+            _this.id = id;
+            _this.alias = alias;
+            _this.varFlags = VarFlags.None;
+            _this.isDynamicImport = false;
         }
         ImportDeclaration.prototype.isStatementOrExpression = function () { return true; };
         ImportDeclaration.prototype.emit = function (emitter, tokenId, startLine) {
@@ -3236,12 +3236,12 @@ var TypeScript;
         function BoundDecl(id, nodeType, nestingLevel) {
             var _this;
             _this = _super.call(this, nodeType) || this;
-            this.id = id;
-            this.nestingLevel = nestingLevel;
-            this.init = null;
-            this.typeExpr = null;
-            this.varFlags = VarFlags.None;
-            this.sym = null;
+            _this.id = id;
+            _this.nestingLevel = nestingLevel;
+            _this.init = null;
+            _this.typeExpr = null;
+            _this.varFlags = VarFlags.None;
+            _this.sym = null;
         }
         BoundDecl.prototype.isStatementOrExpression = function () { return true; };
         BoundDecl.prototype.isPrivate = function () { return hasFlag(this.varFlags, VarFlags.Private); };
@@ -3279,8 +3279,8 @@ var TypeScript;
         function ArgDecl(id) {
             var _this;
             _this = _super.call(this, id, NodeType.ArgDecl, 0) || this;
-            this.isOptional = false;
-            this.parameterPropertySym = null;
+            _this.isOptional = false;
+            _this.parameterPropertySym = null;
         }
         ArgDecl.prototype.isOptionalArg = function () { return this.isOptional || this.init; };
         ArgDecl.prototype.treeViewLabel = function () {
@@ -3302,35 +3302,35 @@ var TypeScript;
         function FuncDecl(name, bod, isConstructor, arguments, vars, scopes, statics, nodeType) {
             var _this;
             _this = _super.call(this, nodeType) || this;
-            this.name = name;
-            this.bod = bod;
-            this.isConstructor = isConstructor;
-            this.arguments = arguments;
-            this.vars = vars;
-            this.scopes = scopes;
-            this.statics = statics;
-            this.hint = null;
-            this.fncFlags = FncFlags.None;
-            this.returnTypeAnnotation = null;
-            this.variableArgList = false;
-            this.jumpRefs = null;
-            this.internalNameCache = null;
-            this.tmp1Declared = false;
-            this.enclosingFnc = null;
-            this.freeVariables = [];
-            this.unitIndex = -1;
-            this.classDecl = null;
-            this.boundToProperty = null;
-            this.isOverload = false;
-            this.innerStaticFuncs = [];
-            this.isTargetTypedAsMethod = false;
-            this.isInlineCallLiteral = false;
-            this.accessorSymbol = null;
-            this.leftCurlyCount = 0;
-            this.rightCurlyCount = 0;
-            this.returnStatementsWithExpressions = [];
-            this.scopeType = null; // Type of the FuncDecl, before target typing
-            this.endingToken = null;
+            _this.name = name;
+            _this.bod = bod;
+            _this.isConstructor = isConstructor;
+            _this.arguments = arguments;
+            _this.vars = vars;
+            _this.scopes = scopes;
+            _this.statics = statics;
+            _this.hint = null;
+            _this.fncFlags = FncFlags.None;
+            _this.returnTypeAnnotation = null;
+            _this.variableArgList = false;
+            _this.jumpRefs = null;
+            _this.internalNameCache = null;
+            _this.tmp1Declared = false;
+            _this.enclosingFnc = null;
+            _this.freeVariables = [];
+            _this.unitIndex = -1;
+            _this.classDecl = null;
+            _this.boundToProperty = null;
+            _this.isOverload = false;
+            _this.innerStaticFuncs = [];
+            _this.isTargetTypedAsMethod = false;
+            _this.isInlineCallLiteral = false;
+            _this.accessorSymbol = null;
+            _this.leftCurlyCount = 0;
+            _this.rightCurlyCount = 0;
+            _this.returnStatementsWithExpressions = [];
+            _this.scopeType = null; // Type of the FuncDecl, before target typing
+            _this.endingToken = null;
         }
         FuncDecl.prototype.internalName = function () {
             if (this.internalNameCache == null) {
@@ -3443,21 +3443,21 @@ var TypeScript;
         function Script(vars, scopes) {
             var _this;
             _this = _super.call(this, new Identifier("script"), null, false, null, vars, scopes, null, NodeType.Script) || this;
-            this.locationInfo = null;
-            this.referencedFiles = [];
-            this.requiresGlobal = false;
-            this.requiresInherits = false;
-            this.isResident = false;
-            this.isDeclareFile = false;
-            this.hasBeenTypeChecked = false;
-            this.topLevelMod = null;
-            this.leftCurlyCount = 0;
-            this.rightCurlyCount = 0;
+            _this.locationInfo = null;
+            _this.referencedFiles = [];
+            _this.requiresGlobal = false;
+            _this.requiresInherits = false;
+            _this.isResident = false;
+            _this.isDeclareFile = false;
+            _this.hasBeenTypeChecked = false;
+            _this.topLevelMod = null;
+            _this.leftCurlyCount = 0;
+            _this.rightCurlyCount = 0;
             // Remember if the script contains Unicode chars, that is needed when generating code for this script object to decide the output file correct encoding.
-            this.containsUnicodeChar = false;
-            this.containsUnicodeCharInComment = false;
-            this.vars = vars;
-            this.scopes = scopes;
+            _this.containsUnicodeChar = false;
+            _this.containsUnicodeCharInComment = false;
+            _this.vars = vars;
+            _this.scopes = scopes;
         }
         Script.prototype.typeCheck = function (typeFlow) {
             return typeFlow.typeCheckScript(this);
@@ -3513,10 +3513,10 @@ var TypeScript;
         function NamedDeclaration(nodeType, name, members) {
             var _this;
             _this = _super.call(this, nodeType) || this;
-            this.name = name;
-            this.members = members;
-            this.leftCurlyCount = 0;
-            this.rightCurlyCount = 0;
+            _this.name = name;
+            _this.members = members;
+            _this.leftCurlyCount = 0;
+            _this.rightCurlyCount = 0;
         }
         return NamedDeclaration;
     }(ModuleElement));
@@ -3526,15 +3526,15 @@ var TypeScript;
         function ModuleDeclaration(name, members, vars, scopes, endingToken) {
             var _this;
             _this = _super.call(this, NodeType.ModuleDeclaration, name, members) || this;
-            this.endingToken = endingToken;
-            this.modFlags = ModuleFlags.ShouldEmitModuleDecl;
-            this.amdDependencies = [];
+            _this.endingToken = endingToken;
+            _this.modFlags = ModuleFlags.ShouldEmitModuleDecl;
+            _this.amdDependencies = [];
             // Remember if the module contains Unicode chars, that is needed for dynamic module as we will generate a file for each.
-            this.containsUnicodeChar = false;
-            this.containsUnicodeCharInComment = false;
-            this.vars = vars;
-            this.scopes = scopes;
-            this.prettyName = this.name.actualText;
+            _this.containsUnicodeChar = false;
+            _this.containsUnicodeCharInComment = false;
+            _this.vars = vars;
+            _this.scopes = scopes;
+            _this.prettyName = _this.name.actualText;
         }
         ModuleDeclaration.prototype.isExported = function () { return hasFlag(this.modFlags, ModuleFlags.Exported); };
         ModuleDeclaration.prototype.isAmbient = function () { return hasFlag(this.modFlags, ModuleFlags.Ambient); };
@@ -3562,9 +3562,9 @@ var TypeScript;
         function TypeDeclaration(nodeType, name, extendsList, implementsList, members) {
             var _this;
             _this = _super.call(this, nodeType, name, members) || this;
-            this.extendsList = extendsList;
-            this.implementsList = implementsList;
-            this.varFlags = VarFlags.None;
+            _this.extendsList = extendsList;
+            _this.implementsList = implementsList;
+            _this.varFlags = VarFlags.None;
         }
         TypeDeclaration.prototype.isExported = function () {
             return hasFlag(this.varFlags, VarFlags.Exported);
@@ -3580,10 +3580,10 @@ var TypeScript;
         function ClassDeclaration(name, members, extendsList, implementsList) {
             var _this;
             _this = _super.call(this, NodeType.ClassDeclaration, name, extendsList, implementsList, members) || this;
-            this.knownMemberNames = {};
-            this.constructorDecl = null;
-            this.constructorNestingLevel = 0;
-            this.endingToken = null;
+            _this.knownMemberNames = {};
+            _this.constructorDecl = null;
+            _this.constructorNestingLevel = 0;
+            _this.endingToken = null;
         }
         ClassDeclaration.prototype.typeCheck = function (typeFlow) {
             return typeFlow.typeCheckClass(this);
@@ -3613,7 +3613,7 @@ var TypeScript;
         function Statement(nodeType) {
             var _this;
             _this = _super.call(this, nodeType) || this;
-            this.flags |= ASTFlags.IsStatement;
+            _this.flags |= ASTFlags.IsStatement;
         }
         Statement.prototype.isLoop = function () { return false; };
         Statement.prototype.isStatementOrExpression = function () { return true; };
@@ -3630,8 +3630,8 @@ var TypeScript;
         function LabeledStatement(labels, stmt) {
             var _this;
             _this = _super.call(this, NodeType.LabeledStatement) || this;
-            this.labels = labels;
-            this.stmt = stmt;
+            _this.labels = labels;
+            _this.stmt = stmt;
         }
         LabeledStatement.prototype.emit = function (emitter, tokenId, startLine) {
             emitter.emitParensAndCommentsInPlace(this, true);
@@ -3665,8 +3665,8 @@ var TypeScript;
         function Block(statements, isStatementBlock) {
             var _this;
             _this = _super.call(this, NodeType.Block) || this;
-            this.statements = statements;
-            this.isStatementBlock = isStatementBlock;
+            _this.statements = statements;
+            _this.isStatementBlock = isStatementBlock;
         }
         Block.prototype.emit = function (emitter, tokenId, startLine) {
             emitter.emitParensAndCommentsInPlace(this, true);
@@ -3721,8 +3721,8 @@ var TypeScript;
         function Jump(nodeType) {
             var _this;
             _this = _super.call(this, nodeType) || this;
-            this.target = null;
-            this.resolvedTarget = null;
+            _this.target = null;
+            _this.resolvedTarget = null;
         }
         Jump.prototype.hasExplicitTarget = function () { return (this.target); };
         Jump.prototype.setResolvedTarget = function (parser, stmt) {
@@ -3773,8 +3773,8 @@ var TypeScript;
         function WhileStatement(cond) {
             var _this;
             _this = _super.call(this, NodeType.While) || this;
-            this.cond = cond;
-            this.body = null;
+            _this.cond = cond;
+            _this.body = null;
         }
         WhileStatement.prototype.isLoop = function () { return true; };
         WhileStatement.prototype.emit = function (emitter, tokenId, startLine) {
@@ -3826,9 +3826,9 @@ var TypeScript;
         function DoWhileStatement() {
             var _this;
             _this = _super.call(this, NodeType.DoWhile) || this;
-            this.body = null;
-            this.whileAST = null;
-            this.cond = null;
+            _this.body = null;
+            _this.whileAST = null;
+            _this.cond = null;
         }
         DoWhileStatement.prototype.isLoop = function () { return true; };
         DoWhileStatement.prototype.emit = function (emitter, tokenId, startLine) {
@@ -3883,9 +3883,9 @@ var TypeScript;
         function IfStatement(cond) {
             var _this;
             _this = _super.call(this, NodeType.If) || this;
-            this.cond = cond;
-            this.elseBod = null;
-            this.statement = new ASTSpan();
+            _this.cond = cond;
+            _this.elseBod = null;
+            _this.statement = new ASTSpan();
         }
         IfStatement.prototype.isCompoundStatement = function () { return true; };
         IfStatement.prototype.emit = function (emitter, tokenId, startLine) {
@@ -3962,7 +3962,7 @@ var TypeScript;
         function ReturnStatement() {
             var _this;
             _this = _super.call(this, NodeType.Return) || this;
-            this.returnExpression = null;
+            _this.returnExpression = null;
         }
         ReturnStatement.prototype.emit = function (emitter, tokenId, startLine) {
             emitter.emitParensAndCommentsInPlace(this, true);
@@ -4003,11 +4003,11 @@ var TypeScript;
         function ForInStatement(lval, obj) {
             var _this;
             _this = _super.call(this, NodeType.ForIn) || this;
-            this.lval = lval;
-            this.obj = obj;
-            this.statement = new ASTSpan();
-            if (this.lval && (this.lval.nodeType == NodeType.VarDecl)) {
-                this.lval.varFlags |= VarFlags.AutoInit;
+            _this.lval = lval;
+            _this.obj = obj;
+            _this.statement = new ASTSpan();
+            if (_this.lval && (_this.lval.nodeType == NodeType.VarDecl)) {
+                _this.lval.varFlags |= VarFlags.AutoInit;
             }
         }
         ForInStatement.prototype.isLoop = function () { return true; };
@@ -4119,7 +4119,7 @@ var TypeScript;
         function ForStatement(init) {
             var _this;
             _this = _super.call(this, NodeType.For) || this;
-            this.init = init;
+            _this.init = init;
         }
         ForStatement.prototype.isLoop = function () { return true; };
         ForStatement.prototype.emit = function (emitter, tokenId, startLine) {
@@ -4211,8 +4211,8 @@ var TypeScript;
         function WithStatement(expr) {
             var _this;
             _this = _super.call(this, NodeType.With) || this;
-            this.expr = expr;
-            this.withSym = null;
+            _this.expr = expr;
+            _this.withSym = null;
         }
         WithStatement.prototype.isCompoundStatement = function () { return true; };
         WithStatement.prototype.emit = function (emitter, tokenId, startLine) {
@@ -4238,9 +4238,9 @@ var TypeScript;
         function SwitchStatement(val) {
             var _this;
             _this = _super.call(this, NodeType.Switch) || this;
-            this.val = val;
-            this.defaultCase = null;
-            this.statement = new ASTSpan();
+            _this.val = val;
+            _this.defaultCase = null;
+            _this.statement = new ASTSpan();
         }
         SwitchStatement.prototype.isCompoundStatement = function () { return true; };
         SwitchStatement.prototype.emit = function (emitter, tokenId, startLine) {
@@ -4311,7 +4311,7 @@ var TypeScript;
         function CaseStatement() {
             var _this;
             _this = _super.call(this, NodeType.Case) || this;
-            this.expr = null;
+            _this.expr = null;
         }
         CaseStatement.prototype.emit = function (emitter, tokenId, startLine) {
             emitter.emitParensAndCommentsInPlace(this, true);
@@ -4365,8 +4365,8 @@ var TypeScript;
         function TypeReference(term, arrayCount) {
             var _this;
             _this = _super.call(this, NodeType.TypeRef) || this;
-            this.term = term;
-            this.arrayCount = arrayCount;
+            _this.term = term;
+            _this.arrayCount = arrayCount;
         }
         TypeReference.prototype.emit = function (emitter, tokenId, startLine) {
             throw new Error("should not emit a type ref");
@@ -4396,8 +4396,8 @@ var TypeScript;
         function TryFinally(tryNode, finallyNode) {
             var _this;
             _this = _super.call(this, NodeType.TryFinally) || this;
-            this.tryNode = tryNode;
-            this.finallyNode = finallyNode;
+            _this.tryNode = tryNode;
+            _this.finallyNode = finallyNode;
         }
         TryFinally.prototype.isCompoundStatement = function () { return true; };
         TryFinally.prototype.emit = function (emitter, tokenId, startLine) {
@@ -4442,8 +4442,8 @@ var TypeScript;
         function TryCatch(tryNode, catchNode) {
             var _this;
             _this = _super.call(this, NodeType.TryCatch) || this;
-            this.tryNode = tryNode;
-            this.catchNode = catchNode;
+            _this.tryNode = tryNode;
+            _this.catchNode = catchNode;
         }
         TryCatch.prototype.isCompoundStatement = function () { return true; };
         TryCatch.prototype.emit = function (emitter, tokenId, startLine) {
@@ -4493,7 +4493,7 @@ var TypeScript;
         function Try(body) {
             var _this;
             _this = _super.call(this, NodeType.Try) || this;
-            this.body = body;
+            _this.body = body;
         }
         Try.prototype.emit = function (emitter, tokenId, startLine) {
             emitter.emitParensAndCommentsInPlace(this, true);
@@ -4522,12 +4522,12 @@ var TypeScript;
         function Catch(param, body) {
             var _this;
             _this = _super.call(this, NodeType.Catch) || this;
-            this.param = param;
-            this.body = body;
-            this.statement = new ASTSpan();
-            this.containedScope = null;
-            if (this.param) {
-                this.param.varFlags |= VarFlags.AutoInit;
+            _this.param = param;
+            _this.body = body;
+            _this.statement = new ASTSpan();
+            _this.containedScope = null;
+            if (_this.param) {
+                _this.param.varFlags |= VarFlags.AutoInit;
             }
         }
         Catch.prototype.emit = function (emitter, tokenId, startLine) {
@@ -4596,7 +4596,7 @@ var TypeScript;
         function Finally(body) {
             var _this;
             _this = _super.call(this, NodeType.Finally) || this;
-            this.body = body;
+            _this.body = body;
         }
         Finally.prototype.emit = function (emitter, tokenId, startLine) {
             emitter.emitParensAndCommentsInPlace(this, true);
@@ -4625,10 +4625,10 @@ var TypeScript;
         function Comment(content, isBlockComment, endsLine) {
             var _this;
             _this = _super.call(this, NodeType.Comment) || this;
-            this.content = content;
-            this.isBlockComment = isBlockComment;
-            this.endsLine = endsLine;
-            this.text = null;
+            _this.content = content;
+            _this.isBlockComment = isBlockComment;
+            _this.endsLine = endsLine;
+            _this.text = null;
         }
         Comment.prototype.getText = function () {
             if (this.text == null) {
diff --git a/tests/baselines/reference/parserharness.js b/tests/baselines/reference/parserharness.js
index 3f7e05e7164..f0db6078832 100644
--- a/tests/baselines/reference/parserharness.js
+++ b/tests/baselines/reference/parserharness.js
@@ -2382,8 +2382,8 @@ var Harness;
         function TestCase(description, block) {
             var _this;
             _this = _super.call(this, description, block) || this;
-            this.description = description;
-            this.block = block;
+            _this.description = description;
+            _this.block = block;
         }
         TestCase.prototype.addChild = function (child) {
             throw new Error("Testcases may not be nested inside other testcases");
@@ -2417,8 +2417,8 @@ var Harness;
         function Scenario(description, block) {
             var _this;
             _this = _super.call(this, description, block) || this;
-            this.description = description;
-            this.block = block;
+            _this.description = description;
+            _this.block = block;
         }
         /** Run the block, and if the block doesn't raise an error, run the children. */
         Scenario.prototype.run = function (done) {
diff --git a/tests/baselines/reference/privateInstanceMemberAccessibility.js b/tests/baselines/reference/privateInstanceMemberAccessibility.js
index cfdc137aedf..618c38b89d5 100644
--- a/tests/baselines/reference/privateInstanceMemberAccessibility.js
+++ b/tests/baselines/reference/privateInstanceMemberAccessibility.js
@@ -29,8 +29,8 @@ var Derived = (function (_super) {
     function Derived() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.x = _super.prototype.foo; // error
-        this.z = _super.prototype.foo; // error
+        _this.x = _super.prototype.foo; // error
+        _this.z = _super.prototype.foo; // error
     }
     Derived.prototype.y = function () {
         return _super.prototype.foo; // error
diff --git a/tests/baselines/reference/privateStaticMemberAccessibility.js b/tests/baselines/reference/privateStaticMemberAccessibility.js
index aad41d01b07..e953198290b 100644
--- a/tests/baselines/reference/privateStaticMemberAccessibility.js
+++ b/tests/baselines/reference/privateStaticMemberAccessibility.js
@@ -24,7 +24,7 @@ var Derived = (function (_super) {
     function Derived() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.bing = function () { return Base.foo; }; // error
+        _this.bing = function () { return Base.foo; }; // error
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/readonlyConstructorAssignment.js b/tests/baselines/reference/readonlyConstructorAssignment.js
index 1c1e2a94ff1..f1b69ecc00b 100644
--- a/tests/baselines/reference/readonlyConstructorAssignment.js
+++ b/tests/baselines/reference/readonlyConstructorAssignment.js
@@ -59,7 +59,7 @@ var B = (function (_super) {
         var _this;
         _this = _super.call(this, x) || this;
         // Fails, x is readonly
-        this.x = 1;
+        _this.x = 1;
     }
     return B;
 }(A));
@@ -70,8 +70,8 @@ var C = (function (_super) {
     function C(x) {
         var _this;
         _this = _super.call(this, x) || this;
-        this.x = x;
-        this.x = 1;
+        _this.x = x;
+        _this.x = 1;
     }
     return C;
 }(A));
@@ -88,8 +88,8 @@ var E = (function (_super) {
     function E(x) {
         var _this;
         _this = _super.call(this, x) || this;
-        this.x = x;
-        this.x = 1;
+        _this.x = x;
+        _this.x = 1;
     }
     return E;
 }(D));
diff --git a/tests/baselines/reference/scopeTests.js b/tests/baselines/reference/scopeTests.js
index e9394a64c9b..3fd9018e945 100644
--- a/tests/baselines/reference/scopeTests.js
+++ b/tests/baselines/reference/scopeTests.js
@@ -27,8 +27,8 @@ var D = (function (_super) {
     function D() {
         var _this;
         _this = _super.call(this) || this;
-        this.v = 1;
-        this.p = 1;
+        _this.v = 1;
+        _this.p = 1;
         C.s = 1;
     }
     return D;
diff --git a/tests/baselines/reference/staticInheritance.js b/tests/baselines/reference/staticInheritance.js
index 8b4b8326cab..462f2382f3c 100644
--- a/tests/baselines/reference/staticInheritance.js
+++ b/tests/baselines/reference/staticInheritance.js
@@ -29,8 +29,8 @@ var B = (function (_super) {
     function B() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.p1 = doThing(A); // OK
-        this.p2 = doThing(B); // OK
+        _this.p1 = doThing(A); // OK
+        _this.p2 = doThing(B); // OK
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/staticPropSuper.js b/tests/baselines/reference/staticPropSuper.js
index b2eea36eece..f5bac0135af 100644
--- a/tests/baselines/reference/staticPropSuper.js
+++ b/tests/baselines/reference/staticPropSuper.js
@@ -60,7 +60,7 @@ var C = (function (_super) {
     __extends(C, _super);
     function C() {
         var _this;
-        this.p = 10;
+        _this.p = 10;
         var x = 1; // should error
     }
     return C;
@@ -69,7 +69,7 @@ var D = (function (_super) {
     __extends(D, _super);
     function D() {
         var _this;
-        this.p = 11;
+        _this.p = 11;
         var x = 1; // should error
     }
     return D;
@@ -78,7 +78,7 @@ var E = (function (_super) {
     __extends(E, _super);
     function E() {
         var _this;
-        this.p = 12;
+        _this.p = 12;
         var x = 1; // should error
     }
     return E;
diff --git a/tests/baselines/reference/strictModeInConstructor.js b/tests/baselines/reference/strictModeInConstructor.js
index e40e0c45a59..1af13b1ce7a 100644
--- a/tests/baselines/reference/strictModeInConstructor.js
+++ b/tests/baselines/reference/strictModeInConstructor.js
@@ -77,7 +77,7 @@ var B = (function (_super) {
         var _this;
         "use strict"; // No error
         _this = _super.call(this) || this;
-        this.s = 9;
+        _this.s = 9;
     }
     return B;
 }(A));
@@ -86,7 +86,7 @@ var C = (function (_super) {
     function C() {
         var _this;
         _this = _super.call(this) || this; // No error
-        this.s = 9;
+        _this.s = 9;
         "use strict";
     }
     return C;
@@ -95,7 +95,7 @@ var D = (function (_super) {
     __extends(D, _super);
     function D() {
         var _this;
-        this.s = 9;
+        _this.s = 9;
         var x = 1; // Error
         _this = _super.call(this) || this;
         "use strict";
diff --git a/tests/baselines/reference/superAccess2.js b/tests/baselines/reference/superAccess2.js
index ff711ca8d75..807347e1d16 100644
--- a/tests/baselines/reference/superAccess2.js
+++ b/tests/baselines/reference/superAccess2.js
@@ -46,8 +46,8 @@ var Q = (function (_super) {
         if (zz === void 0) { zz = _super.; }
         if (zzz === void 0) { zzz = function () { return _super.; }; }
         _this = _super.call(this) || this;
-        this.z = z;
-        this.xx = _super.prototype.;
+        _this.z = z;
+        _this.xx = _super.prototype.;
     }
     Q.prototype.foo = function (zz) {
         if (zz === void 0) { zz = _super.prototype.; }
diff --git a/tests/baselines/reference/superCallArgsMustMatch.js b/tests/baselines/reference/superCallArgsMustMatch.js
index 3dec9369dd4..770cb0bf79f 100644
--- a/tests/baselines/reference/superCallArgsMustMatch.js
+++ b/tests/baselines/reference/superCallArgsMustMatch.js
@@ -44,7 +44,7 @@ var T6 = (function (_super) {
         // Should error; base constructor has type T for first arg,
         // which is instantiated with 'number' in the extends clause
         _this = _super.call(this, "hi") || this;
-        var x = this.foo;
+        var x = _this.foo;
     }
     return T6;
 }(T5));
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing1.js b/tests/baselines/reference/superCallBeforeThisAccessing1.js
index e70dde9fd8e..6af4482f371 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing1.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing1.js
@@ -33,7 +33,7 @@ var D = (function (_super) {
         var _this;
         _this = _super.call(this, i) || this;
         var s = {
-            t: this._t
+            t: _this._t
         };
         var i = Factory.create(s);
     }
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing3.js b/tests/baselines/reference/superCallBeforeThisAccessing3.js
index 1f4c8114913..f77cb964179 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing3.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing3.js
@@ -30,7 +30,7 @@ var D = (function (_super) {
         var _this;
         var x = function () { _this._t; };
         x(); // no error; we only check super is called before this when the container is a constructor
-        this._t; // error
+        _this._t; // error
         _this = _super.call(this, undefined) || this;
     }
     return D;
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing4.js b/tests/baselines/reference/superCallBeforeThisAccessing4.js
index 2645eaa9795..c147b0d84cc 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing4.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing4.js
@@ -25,7 +25,7 @@ var D = (function (_super) {
     __extends(D, _super);
     function D() {
         var _this;
-        this._t;
+        _this._t;
         _this = _super.call(this) || this;
     }
     return D;
@@ -35,7 +35,7 @@ var E = (function (_super) {
     function E() {
         var _this;
         _this = _super.call(this) || this;
-        this._t;
+        _this._t;
     }
     return E;
 }(null));
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing5.js b/tests/baselines/reference/superCallBeforeThisAccessing5.js
index df345ec5c26..8fff8068ec0 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing5.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing5.js
@@ -17,7 +17,7 @@ var D = (function (_super) {
     __extends(D, _super);
     function D() {
         var _this;
-        this._t; // No error
+        _this._t; // No error
     }
     return D;
 }(null));
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing6.js b/tests/baselines/reference/superCallBeforeThisAccessing6.js
index d4e8c979552..843a1d3b2cf 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing6.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing6.js
@@ -25,7 +25,7 @@ var D = (function (_super) {
     __extends(D, _super);
     function D() {
         var _this;
-        _this = _super.call(this, this) || this;
+        _this = _super.call(this, _this) || this;
     }
     return D;
 }(Base));
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing7.js b/tests/baselines/reference/superCallBeforeThisAccessing7.js
index f6c41b144eb..d6ad948a08c 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing7.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing7.js
@@ -29,7 +29,7 @@ var D = (function (_super) {
     function D() {
         var _this;
         var x = {
-            j: this._t
+            j: _this._t
         };
         _this = _super.call(this, undefined) || this;
     }
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing8.js b/tests/baselines/reference/superCallBeforeThisAccessing8.js
index 7d09351621a..cbf0236c4cc 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing8.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing8.js
@@ -30,7 +30,7 @@ var D = (function (_super) {
         var _this;
         var x = {
             k: _this = _super.call(this, undefined) || this,
-            j: this._t
+            j: _this._t
         };
     }
     return D;
diff --git a/tests/baselines/reference/superCallInNonStaticMethod.js b/tests/baselines/reference/superCallInNonStaticMethod.js
index 6640a32be5a..1dd120eeb5c 100644
--- a/tests/baselines/reference/superCallInNonStaticMethod.js
+++ b/tests/baselines/reference/superCallInNonStaticMethod.js
@@ -68,9 +68,9 @@ var Other = (function (_super) {
     function Other() {
         var _this;
         _this = _super.call(this) || this;
-        this.propertyInitializer = _super.prototype.instanceMethod.call(this);
-        this.functionProperty = function () { _super.prototype.instanceMethod.call(_this); };
-        _super.prototype.instanceMethod.call(this);
+        _this.propertyInitializer = _super.prototype.instanceMethod.call(_this);
+        _this.functionProperty = function () { _super.prototype.instanceMethod.call(_this); };
+        _super.prototype.instanceMethod.call(_this);
     }
     // in instance method
     Other.prototype.instanceMethod = function () {
diff --git a/tests/baselines/reference/superCallOutsideConstructor.js b/tests/baselines/reference/superCallOutsideConstructor.js
index fd91de4cc8e..774dde72340 100644
--- a/tests/baselines/reference/superCallOutsideConstructor.js
+++ b/tests/baselines/reference/superCallOutsideConstructor.js
@@ -39,9 +39,9 @@ var D = (function (_super) {
     function D() {
         var _this;
         _this = _super.call(this) || this;
-        this.x = _this = _super.call(this) || this;
+        _this.x = _this = _super.call(this) || this;
         var y = function () {
-            _this = _super.call(_this) || _this;
+            _this = _super.call(this) || this;
         };
         var y2 = function () {
             _this = _super.call(this) || this;
diff --git a/tests/baselines/reference/superCallParameterContextualTyping3.js b/tests/baselines/reference/superCallParameterContextualTyping3.js
index cfa3fd1c074..d77df52ddd6 100644
--- a/tests/baselines/reference/superCallParameterContextualTyping3.js
+++ b/tests/baselines/reference/superCallParameterContextualTyping3.js
@@ -57,7 +57,7 @@ var C = (function (_super) {
         }) || this;
         // Should be okay.
         // 'p' should have type 'string'.
-        _super.prototype.foo.call(this, {
+        _super.prototype.foo.call(_this, {
             method: function (p) {
                 p.length;
             }
diff --git a/tests/baselines/reference/superCalls.js b/tests/baselines/reference/superCalls.js
index 96b0061f47e..33127da6437 100644
--- a/tests/baselines/reference/superCalls.js
+++ b/tests/baselines/reference/superCalls.js
@@ -49,7 +49,7 @@ var Derived = (function (_super) {
     function Derived(q) {
         var _this;
         _this = _super.call(this, '') || this;
-        this.q = q;
+        _this.q = q;
         //type of super call expression is void
         var p = _this = _super.call(this, '') || this;
         var p = v();
diff --git a/tests/baselines/reference/superErrors.js b/tests/baselines/reference/superErrors.js
index f962876a391..2e68370fc32 100644
--- a/tests/baselines/reference/superErrors.js
+++ b/tests/baselines/reference/superErrors.js
@@ -78,7 +78,7 @@ var RegisteredUser = (function (_super) {
     function RegisteredUser() {
         var _this;
         _this = _super.call(this) || this;
-        this.name = "Frank";
+        _this.name = "Frank";
         // super call in an inner function in a constructor
         function inner() {
             _super.sayHello.call(this);
diff --git a/tests/baselines/reference/superInConstructorParam1.js b/tests/baselines/reference/superInConstructorParam1.js
index ab1744929a9..56e40b65e10 100644
--- a/tests/baselines/reference/superInConstructorParam1.js
+++ b/tests/baselines/reference/superInConstructorParam1.js
@@ -28,7 +28,7 @@ var C = (function (_super) {
     __extends(C, _super);
     function C(a) {
         var _this;
-        if (a === void 0) { a = _super.foo.call(this); }
+        if (a === void 0) { a = _super.foo.call(_this); }
     }
     return C;
 }(B));
diff --git a/tests/baselines/reference/superInLambdas.js b/tests/baselines/reference/superInLambdas.js
index f2c84cb7e64..5a1f48f3826 100644
--- a/tests/baselines/reference/superInLambdas.js
+++ b/tests/baselines/reference/superInLambdas.js
@@ -87,9 +87,9 @@ var RegisteredUser = (function (_super) {
     function RegisteredUser() {
         var _this;
         _this = _super.call(this) || this;
-        this.name = "Frank";
+        _this.name = "Frank";
         // super call in a constructor
-        _super.prototype.sayHello.call(this);
+        _super.prototype.sayHello.call(_this);
         // super call in a lambda in a constructor 
         var x = function () { return _super.prototype.sayHello.call(_this); };
     }
@@ -107,7 +107,7 @@ var RegisteredUser2 = (function (_super) {
     function RegisteredUser2() {
         var _this;
         _this = _super.call(this) || this;
-        this.name = "Joe";
+        _this.name = "Joe";
         // super call in a nested lambda in a constructor 
         var x = function () { return function () { return function () { return _super.prototype.sayHello.call(_this); }; }; };
     }
@@ -123,7 +123,7 @@ var RegisteredUser3 = (function (_super) {
     function RegisteredUser3() {
         var _this;
         _this = _super.call(this) || this;
-        this.name = "Sam";
+        _this.name = "Sam";
         // super property in a nested lambda in a constructor 
         var superName = function () { return function () { return function () { return _super.prototype.name; }; }; };
     }
@@ -139,7 +139,7 @@ var RegisteredUser4 = (function (_super) {
     function RegisteredUser4() {
         var _this;
         _this = _super.call(this) || this;
-        this.name = "Mark";
+        _this.name = "Mark";
         // super in a nested lambda in a constructor 
         var x = function () { return function () { return _super.prototype.; }; };
     }
diff --git a/tests/baselines/reference/superPropertyAccess1.js b/tests/baselines/reference/superPropertyAccess1.js
index 86f059a2fb2..c9865806570 100644
--- a/tests/baselines/reference/superPropertyAccess1.js
+++ b/tests/baselines/reference/superPropertyAccess1.js
@@ -52,7 +52,7 @@ var D = (function (_super) {
     function D() {
         var _this;
         _this = _super.call(this) || this;
-        _super.prototype.bar.call(this);
+        _super.prototype.bar.call(_this);
         _super.prototype.x; // error
     }
     D.prototype.foo = function () {
diff --git a/tests/baselines/reference/superPropertyAccess2.js b/tests/baselines/reference/superPropertyAccess2.js
index be0c44b4081..df6e08177cb 100644
--- a/tests/baselines/reference/superPropertyAccess2.js
+++ b/tests/baselines/reference/superPropertyAccess2.js
@@ -52,7 +52,7 @@ var D = (function (_super) {
     function D() {
         var _this;
         _this = _super.call(this) || this;
-        _super.prototype.bar.call(this); // error
+        _super.prototype.bar.call(_this); // error
         _super.prototype.x; // error
     }
     D.foo = function () {
diff --git a/tests/baselines/reference/superPropertyAccessNoError.js b/tests/baselines/reference/superPropertyAccessNoError.js
index f7663eab6e0..d8dda26288c 100644
--- a/tests/baselines/reference/superPropertyAccessNoError.js
+++ b/tests/baselines/reference/superPropertyAccessNoError.js
@@ -101,7 +101,7 @@ var SomeDerivedClass = (function (_super) {
     function SomeDerivedClass() {
         var _this;
         _this = _super.call(this) || this;
-        var x = _super.prototype.func.call(this);
+        var x = _super.prototype.func.call(_this);
         var x;
     }
     SomeDerivedClass.prototype.fn = function () {
diff --git a/tests/baselines/reference/superPropertyAccess_ES5.js b/tests/baselines/reference/superPropertyAccess_ES5.js
index 14492c2788a..1d2ab4c2a3f 100644
--- a/tests/baselines/reference/superPropertyAccess_ES5.js
+++ b/tests/baselines/reference/superPropertyAccess_ES5.js
@@ -51,7 +51,7 @@ var MyDerived = (function (_super) {
     function MyDerived() {
         var _this;
         _this = _super.call(this) || this;
-        var f1 = _super.prototype.getValue.call(this);
+        var f1 = _super.prototype.getValue.call(_this);
         var f2 = _super.prototype.value;
     }
     return MyDerived;
diff --git a/tests/baselines/reference/superWithTypeArgument.js b/tests/baselines/reference/superWithTypeArgument.js
index a4acd321f50..cc46fa96896 100644
--- a/tests/baselines/reference/superWithTypeArgument.js
+++ b/tests/baselines/reference/superWithTypeArgument.js
@@ -24,7 +24,7 @@ var D = (function (_super) {
     __extends(D, _super);
     function D() {
         var _this;
-        _super.prototype..call(this);
+        _super.prototype..call(_this);
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/superWithTypeArgument2.js b/tests/baselines/reference/superWithTypeArgument2.js
index ca399c4de78..4b5176bed96 100644
--- a/tests/baselines/reference/superWithTypeArgument2.js
+++ b/tests/baselines/reference/superWithTypeArgument2.js
@@ -24,7 +24,7 @@ var D = (function (_super) {
     __extends(D, _super);
     function D(x) {
         var _this;
-        _super.prototype..call(this, x);
+        _super.prototype..call(_this, x);
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/superWithTypeArgument3.js b/tests/baselines/reference/superWithTypeArgument3.js
index 5a124586d0c..aa70803de4d 100644
--- a/tests/baselines/reference/superWithTypeArgument3.js
+++ b/tests/baselines/reference/superWithTypeArgument3.js
@@ -29,7 +29,7 @@ var D = (function (_super) {
     __extends(D, _super);
     function D() {
         var _this;
-        _super.prototype..call(this);
+        _super.prototype..call(_this);
     }
     D.prototype.bar = function () {
         _super.prototype.bar.call(this, null);
diff --git a/tests/baselines/reference/thisInInvalidContexts.js b/tests/baselines/reference/thisInInvalidContexts.js
index 2a86b144ae5..218ebfb1686 100644
--- a/tests/baselines/reference/thisInInvalidContexts.js
+++ b/tests/baselines/reference/thisInInvalidContexts.js
@@ -71,7 +71,7 @@ var ClassWithNoInitializer = (function (_super) {
     //'this' in optional super call
     function ClassWithNoInitializer() {
         var _this;
-        _this = _super.call(this, this) || this; // Error
+        _this = _super.call(this, _this) || this; // Error
     }
     return ClassWithNoInitializer;
 }(BaseErrClass));
@@ -80,8 +80,8 @@ var ClassWithInitializer = (function (_super) {
     //'this' in required super call
     function ClassWithInitializer() {
         var _this;
-        _this = _super.call(this, this) || this; // Error
-        this.t = 4;
+        _this = _super.call(this, _this) || this; // Error
+        _this.t = 4;
     }
     return ClassWithInitializer;
 }(BaseErrClass));
diff --git a/tests/baselines/reference/thisInInvalidContextsExternalModule.js b/tests/baselines/reference/thisInInvalidContextsExternalModule.js
index 3748ebaa42f..c14f71ac0b6 100644
--- a/tests/baselines/reference/thisInInvalidContextsExternalModule.js
+++ b/tests/baselines/reference/thisInInvalidContextsExternalModule.js
@@ -72,7 +72,7 @@ var ClassWithNoInitializer = (function (_super) {
     //'this' in optional super call
     function ClassWithNoInitializer() {
         var _this;
-        _this = _super.call(this, this) || this; // error: "super" has to be called before "this" accessing
+        _this = _super.call(this, _this) || this; // error: "super" has to be called before "this" accessing
     }
     return ClassWithNoInitializer;
 }(BaseErrClass));
@@ -81,8 +81,8 @@ var ClassWithInitializer = (function (_super) {
     //'this' in required super call
     function ClassWithInitializer() {
         var _this;
-        _this = _super.call(this, this) || this; // Error
-        this.t = 4;
+        _this = _super.call(this, _this) || this; // Error
+        _this.t = 4;
     }
     return ClassWithInitializer;
 }(BaseErrClass));
diff --git a/tests/baselines/reference/thisInSuperCall.js b/tests/baselines/reference/thisInSuperCall.js
index 91e71522e4d..cf64eebced1 100644
--- a/tests/baselines/reference/thisInSuperCall.js
+++ b/tests/baselines/reference/thisInSuperCall.js
@@ -37,7 +37,7 @@ var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo() {
         var _this;
-        _this = _super.call(this, this) || this; // error: "super" has to be called before "this" accessing
+        _this = _super.call(this, _this) || this; // error: "super" has to be called before "this" accessing
     }
     return Foo;
 }(Base));
@@ -45,8 +45,8 @@ var Foo2 = (function (_super) {
     __extends(Foo2, _super);
     function Foo2() {
         var _this;
-        _this = _super.call(this, this) || this; // error
-        this.p = 0;
+        _this = _super.call(this, _this) || this; // error
+        _this.p = 0;
     }
     return Foo2;
 }(Base));
@@ -54,8 +54,8 @@ var Foo3 = (function (_super) {
     __extends(Foo3, _super);
     function Foo3(p) {
         var _this;
-        _this = _super.call(this, this) || this; // error
-        this.p = p;
+        _this = _super.call(this, _this) || this; // error
+        _this.p = p;
     }
     return Foo3;
 }(Base));
diff --git a/tests/baselines/reference/thisInSuperCall1.js b/tests/baselines/reference/thisInSuperCall1.js
index 8e68c47eb27..eba933d9893 100644
--- a/tests/baselines/reference/thisInSuperCall1.js
+++ b/tests/baselines/reference/thisInSuperCall1.js
@@ -25,8 +25,8 @@ var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo(x) {
         var _this;
-        _this = _super.call(this, this) || this;
-        this.x = x;
+        _this = _super.call(this, _this) || this;
+        _this.x = x;
     }
     return Foo;
 }(Base));
diff --git a/tests/baselines/reference/thisInSuperCall2.js b/tests/baselines/reference/thisInSuperCall2.js
index 6771f15c99b..ed6baabb408 100644
--- a/tests/baselines/reference/thisInSuperCall2.js
+++ b/tests/baselines/reference/thisInSuperCall2.js
@@ -34,7 +34,7 @@ var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo() {
         var _this;
-        _this = _super.call(this, this) || this; // error: "super" has to be called before "this" accessing
+        _this = _super.call(this, _this) || this; // error: "super" has to be called before "this" accessing
     }
     return Foo;
 }(Base));
@@ -42,8 +42,8 @@ var Foo2 = (function (_super) {
     __extends(Foo2, _super);
     function Foo2() {
         var _this;
-        _this = _super.call(this, this) || this; // error
-        this.x = 0;
+        _this = _super.call(this, _this) || this; // error
+        _this.x = 0;
     }
     return Foo2;
 }(Base));
diff --git a/tests/baselines/reference/thisInSuperCall3.js b/tests/baselines/reference/thisInSuperCall3.js
index 4b6c1747d17..d705d5fa7e0 100644
--- a/tests/baselines/reference/thisInSuperCall3.js
+++ b/tests/baselines/reference/thisInSuperCall3.js
@@ -27,8 +27,8 @@ var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo() {
         var _this;
-        _this = _super.call(this, this) || this;
-        this.x = 0;
+        _this = _super.call(this, _this) || this;
+        _this.x = 0;
     }
     return Foo;
 }(Base));
diff --git a/tests/baselines/reference/tsxDynamicTagName5.js b/tests/baselines/reference/tsxDynamicTagName5.js
index 9a64ef6cee6..76b79dbc7dc 100644
--- a/tests/baselines/reference/tsxDynamicTagName5.js
+++ b/tests/baselines/reference/tsxDynamicTagName5.js
@@ -32,7 +32,7 @@ var Text = (function (_super) {
     function Text() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this._tagName = 'div';
+        _this._tagName = 'div';
     }
     Text.prototype.render = function () {
         return (<this._tagName />);
diff --git a/tests/baselines/reference/tsxDynamicTagName7.js b/tests/baselines/reference/tsxDynamicTagName7.js
index 30500b37ce5..c55ceb100ea 100644
--- a/tests/baselines/reference/tsxDynamicTagName7.js
+++ b/tests/baselines/reference/tsxDynamicTagName7.js
@@ -32,7 +32,7 @@ var Text = (function (_super) {
     function Text() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this._tagName = 'div';
+        _this._tagName = 'div';
     }
     Text.prototype.render = function () {
         return (<this /> // this should be an error
diff --git a/tests/baselines/reference/tsxDynamicTagName8.js b/tests/baselines/reference/tsxDynamicTagName8.js
index a6cf3bb45b8..57ce2becbad 100644
--- a/tests/baselines/reference/tsxDynamicTagName8.js
+++ b/tests/baselines/reference/tsxDynamicTagName8.js
@@ -32,7 +32,7 @@ var Text = (function (_super) {
     function Text() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this._tagName = 'div';
+        _this._tagName = 'div';
     }
     Text.prototype.render = function () {
         return (<this._tagName> Hello world </this._tagName>);
diff --git a/tests/baselines/reference/tsxDynamicTagName9.js b/tests/baselines/reference/tsxDynamicTagName9.js
index aa63e614d15..1bc14eb32ee 100644
--- a/tests/baselines/reference/tsxDynamicTagName9.js
+++ b/tests/baselines/reference/tsxDynamicTagName9.js
@@ -32,7 +32,7 @@ var Text = (function (_super) {
     function Text() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this._tagName = 'div';
+        _this._tagName = 'div';
     }
     Text.prototype.render = function () {
         return (<this._tagName> Hello world </this._tagName>);
diff --git a/tests/baselines/reference/typeGuardOfFormThisMember.js b/tests/baselines/reference/typeGuardOfFormThisMember.js
index 63c79ce4c91..fefb1e7ff38 100644
--- a/tests/baselines/reference/typeGuardOfFormThisMember.js
+++ b/tests/baselines/reference/typeGuardOfFormThisMember.js
@@ -120,7 +120,7 @@ var Test;
         function File(path, content) {
             var _this;
             _this = _super.call(this, path) || this;
-            this.content = content;
+            _this.content = content;
         }
         return File;
     }(FileSystemObject));
diff --git a/tests/baselines/reference/typeGuardOfFormThisMemberErrors.js b/tests/baselines/reference/typeGuardOfFormThisMemberErrors.js
index 5c28921a6a7..ed53a308808 100644
--- a/tests/baselines/reference/typeGuardOfFormThisMemberErrors.js
+++ b/tests/baselines/reference/typeGuardOfFormThisMemberErrors.js
@@ -70,7 +70,7 @@ var Test;
         function File(path, content) {
             var _this;
             _this = _super.call(this, path) || this;
-            this.content = content;
+            _this.content = content;
         }
         return File;
     }(FileSystemObject));
diff --git a/tests/baselines/reference/typeRelationships.js b/tests/baselines/reference/typeRelationships.js
index 43c1f7ee146..87f0f60c53f 100644
--- a/tests/baselines/reference/typeRelationships.js
+++ b/tests/baselines/reference/typeRelationships.js
@@ -74,10 +74,10 @@ var D = (function (_super) {
     function D() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.self1 = this;
-        this.self2 = this.self;
-        this.self3 = this.foo();
-        this.d = new D();
+        _this.self1 = _this;
+        _this.self2 = _this.self;
+        _this.self3 = _this.foo();
+        _this.d = new D();
     }
     D.prototype.bar = function () {
         this.self = this.self1;
diff --git a/tests/baselines/reference/unspecializedConstraints.js b/tests/baselines/reference/unspecializedConstraints.js
index b2ea2cac9eb..06d2c4bd6a5 100644
--- a/tests/baselines/reference/unspecializedConstraints.js
+++ b/tests/baselines/reference/unspecializedConstraints.js
@@ -236,9 +236,9 @@ var ts;
         function Property(name, type, flags) {
             var _this;
             _this = _super.call(this) || this;
-            this.name = name;
-            this.type = type;
-            this.flags = flags;
+            _this.name = name;
+            _this.type = type;
+            _this.flags = flags;
         }
         Property.prototype.equals = function (other) {
             return this.name === other.name &&
@@ -257,9 +257,9 @@ var ts;
         function Signature(typeParameters, parameters, returnType) {
             var _this;
             _this = _super.call(this) || this;
-            this.typeParameters = typeParameters;
-            this.parameters = parameters;
-            this.returnType = returnType;
+            _this.typeParameters = typeParameters;
+            _this.parameters = parameters;
+            _this.returnType = returnType;
         }
         Signature.prototype.equalsNoReturn = function (other) {
             return this.parameters.length === other.parameters.length &&
@@ -278,9 +278,9 @@ var ts;
         function Parameter(name, type, flags) {
             var _this;
             _this = _super.call(this) || this;
-            this.name = name;
-            this.type = type;
-            this.flags = flags;
+            _this.name = name;
+            _this.type = type;
+            _this.flags = flags;
         }
         Parameter.prototype.equals = function (other) {
             return this.name === other.name &&
diff --git a/tests/baselines/reference/varArgsOnConstructorTypes.js b/tests/baselines/reference/varArgsOnConstructorTypes.js
index e892cc28a3c..04eaa58a196 100644
--- a/tests/baselines/reference/varArgsOnConstructorTypes.js
+++ b/tests/baselines/reference/varArgsOnConstructorTypes.js
@@ -43,8 +43,8 @@ define(["require", "exports"], function (require, exports) {
         function B(element, url) {
             var _this;
             _this = _super.call(this, element) || this;
-            this.p1 = element;
-            this.p2 = url;
+            _this.p1 = element;
+            _this.p2 = url;
         }
         return B;
     }(A));

From 9c6e148d6e4d4e5f5d33127209343e58ef701f61 Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Fri, 2 Sep 2016 00:12:32 -0700
Subject: [PATCH 05/47] Accepted baselines for sourcemap test.

---
 ...sWithDefaultConstructorAndExtendsClause.js |  4 +-
 ...hDefaultConstructorAndExtendsClause.js.map |  2 +-
 ...tConstructorAndExtendsClause.sourcemap.txt | 50 +++++++++----------
 3 files changed, 28 insertions(+), 28 deletions(-)

diff --git a/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js b/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js
index ea71fbc20c0..29da6d52a38 100644
--- a/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js
+++ b/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js
@@ -23,8 +23,8 @@ var Greeter = (function (_super) {
     function Greeter() {
         var _this;
         _this = _super.apply(this, arguments) || this;
-        this.a = 10;
-        this.nameA = "Ten";
+        _this.a = 10;
+        _this.nameA = "Ten";
     }
     return Greeter;
 }(AbstractGreeter));
diff --git a/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js.map b/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js.map
index e36f2eaaf8e..3a75f3d3b66 100644
--- a/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js.map
+++ b/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js.map
@@ -1,2 +1,2 @@
 //// [sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js.map]
-{"version":3,"file":"sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js","sourceRoot":"","sources":["sourceMapValidationClassWithDefaultConstructorAndExtendsClause.ts"],"names":[],"mappings":";;;;;AAAA;IAAA;IACA,CAAC;IAAD,sBAAC;AAAD,CAAC,AADD,IACC;AAED;IAAsB,2BAAe;IAArC;QAAA,UAGC;;QAFU,MAAC,GAAG,EAAE,CAAC;QACP,UAAK,GAAG,KAAK,CAAC;IACzB,CAAC;IAAD,cAAC;AAAD,CAAC,AAHD,CAAsB,eAAe,GAGpC"}
\ No newline at end of file
+{"version":3,"file":"sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js","sourceRoot":"","sources":["sourceMapValidationClassWithDefaultConstructorAndExtendsClause.ts"],"names":[],"mappings":";;;;;AAAA;IAAA;IACA,CAAC;IAAD,sBAAC;AAAD,CAAC,AADD,IACC;AAED;IAAsB,2BAAe;IAArC;QAAA,UAGC;;QAFU,OAAC,GAAG,EAAE,CAAC;QACP,WAAK,GAAG,KAAK,CAAC;IACzB,CAAC;IAAD,cAAC;AAAD,CAAC,AAHD,CAAsB,eAAe,GAGpC"}
\ No newline at end of file
diff --git a/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.sourcemap.txt b/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.sourcemap.txt
index 3da1d42edcd..7c05c1b4d84 100644
--- a/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.sourcemap.txt
+++ b/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.sourcemap.txt
@@ -94,41 +94,41 @@ sourceFile:sourceMapValidationClassWithDefaultConstructorAndExtendsClause.ts
 2 >Emitted(14, 19) Source(7, 2) + SourceIndex(0)
 ---
 >>>        _this = _super.apply(this, arguments) || this;
->>>        this.a = 10;
+>>>        _this.a = 10;
 1->^^^^^^^^
-2 >        ^^^^^^
-3 >              ^^^
-4 >                 ^^
-5 >                   ^
-6 >                    ^^^^^^^^->
+2 >        ^^^^^^^
+3 >               ^^^
+4 >                  ^^
+5 >                    ^
+6 >                     ^^^^^^^^->
 1->
 2 >        a
-3 >               = 
-4 >                 10
-5 >                   ;
+3 >                = 
+4 >                  10
+5 >                    ;
 1->Emitted(16, 9) Source(5, 12) + SourceIndex(0)
-2 >Emitted(16, 15) Source(5, 13) + SourceIndex(0)
-3 >Emitted(16, 18) Source(5, 16) + SourceIndex(0)
-4 >Emitted(16, 20) Source(5, 18) + SourceIndex(0)
-5 >Emitted(16, 21) Source(5, 19) + SourceIndex(0)
+2 >Emitted(16, 16) Source(5, 13) + SourceIndex(0)
+3 >Emitted(16, 19) Source(5, 16) + SourceIndex(0)
+4 >Emitted(16, 21) Source(5, 18) + SourceIndex(0)
+5 >Emitted(16, 22) Source(5, 19) + SourceIndex(0)
 ---
->>>        this.nameA = "Ten";
+>>>        _this.nameA = "Ten";
 1->^^^^^^^^
-2 >        ^^^^^^^^^^
-3 >                  ^^^
-4 >                     ^^^^^
-5 >                          ^
+2 >        ^^^^^^^^^^^
+3 >                   ^^^
+4 >                      ^^^^^
+5 >                           ^
 1->
   >    public 
 2 >        nameA
-3 >                   = 
-4 >                     "Ten"
-5 >                          ;
+3 >                    = 
+4 >                      "Ten"
+5 >                           ;
 1->Emitted(17, 9) Source(6, 12) + SourceIndex(0)
-2 >Emitted(17, 19) Source(6, 17) + SourceIndex(0)
-3 >Emitted(17, 22) Source(6, 20) + SourceIndex(0)
-4 >Emitted(17, 27) Source(6, 25) + SourceIndex(0)
-5 >Emitted(17, 28) Source(6, 26) + SourceIndex(0)
+2 >Emitted(17, 20) Source(6, 17) + SourceIndex(0)
+3 >Emitted(17, 23) Source(6, 20) + SourceIndex(0)
+4 >Emitted(17, 28) Source(6, 25) + SourceIndex(0)
+5 >Emitted(17, 29) Source(6, 26) + SourceIndex(0)
 ---
 >>>    }
 1 >^^^^

From cd5e76b23c6ffcb7c57ba8cf31660eb4826a86a8 Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Fri, 2 Sep 2016 00:30:15 -0700
Subject: [PATCH 06/47] Always tack on a return statement for '_this' in
 derived classes.

---
 src/compiler/transformers/es6.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/compiler/transformers/es6.ts b/src/compiler/transformers/es6.ts
index 5dd2b154c01..886ee1b8e40 100644
--- a/src/compiler/transformers/es6.ts
+++ b/src/compiler/transformers/es6.ts
@@ -790,7 +790,7 @@ namespace ts {
                 const body = saveStateAndInvoke(constructor, hasSynthesizedSuper ? transformConstructorBodyWithSynthesizedSuper : transformConstructorBodyWithoutSynthesizedSuper);
                 addRange(statements, body);
             }
-            if (constructor ? hasSynthesizedSuper : extendsClauseElement) {
+            if (extendsClauseElement) {
                 statements.push(
                     createReturn(
                         createIdentifier("_this")

From 30ec599c13d99378d8f1a0c27d783e25ed10723d Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Fri, 2 Sep 2016 11:52:13 -0700
Subject: [PATCH 07/47] Accepted baselines.

---
 tests/baselines/reference/abstractProperty.js |  1 +
 .../reference/abstractPropertyNegative.js     |  3 ++
 .../accessOverriddenBaseClassMember1.js       |  1 +
 ...aliasUsageInTypeArgumentOfExtendsClause.js |  1 +
 .../reference/arrowFunctionContexts.js        |  2 +
 .../reference/assignmentLHSIsValue.js         |  1 +
 tests/baselines/reference/autolift4.js        |  1 +
 tests/baselines/reference/baseCheck.js        |  5 ++
 tests/baselines/reference/bases.js            |  1 +
 .../reference/bestCommonTypeOfTuple2.js       |  1 +
 tests/baselines/reference/callWithSpread.js   |  1 +
 .../reference/captureThisInSuperCall.js       |  1 +
 .../reference/checkForObjectTooStrict.js      |  2 +
 .../checkSuperCallBeforeThisAccessing1.js     |  1 +
 .../checkSuperCallBeforeThisAccessing2.js     |  1 +
 .../checkSuperCallBeforeThisAccessing3.js     |  1 +
 .../checkSuperCallBeforeThisAccessing4.js     |  1 +
 .../checkSuperCallBeforeThisAccessing5.js     |  1 +
 .../checkSuperCallBeforeThisAccessing6.js     |  1 +
 .../checkSuperCallBeforeThisAccessing7.js     |  1 +
 .../checkSuperCallBeforeThisAccessing8.js     |  1 +
 .../classConstructorAccessibility2.js         |  3 ++
 ...classConstructorParametersAccessibility.js |  1 +
 ...lassConstructorParametersAccessibility2.js |  1 +
 ...lassConstructorParametersAccessibility3.js |  1 +
 tests/baselines/reference/classExpression3.js |  2 +
 .../reference/classExtendingClassLikeType.js  |  3 ++
 tests/baselines/reference/classExtendsNull.js |  2 +
 .../reference/classSideInheritance2.js        |  1 +
 .../reference/classSideInheritance3.js        |  2 +
 tests/baselines/reference/classUpdateTests.js |  8 ++++
 ...isionSuperAndLocalFunctionInConstructor.js |  2 +
 ...ollisionSuperAndLocalFunctionInProperty.js |  1 +
 .../collisionSuperAndLocalVarInConstructor.js |  2 +
 .../collisionSuperAndLocalVarInProperty.js    |  1 +
 .../reference/collisionSuperAndParameter.js   |  2 +
 ...perAndPropertyNameAsConstuctorParameter.js |  4 ++
 .../reference/commentsInheritance.js          |  1 +
 .../reference/compoundAssignmentLHSIsValue.js |  1 +
 ...poundExponentiationAssignmentLHSIsValue.js |  1 +
 .../reference/computedPropertyNames28_ES5.js  |  1 +
 .../reference/computedPropertyNames30_ES5.js  |  1 +
 tests/baselines/reference/constructorArgs.js  |  1 +
 ...ctorFunctionTypeIsAssignableToBaseType2.js |  2 +
 .../reference/constructorOverloads2.js        |  1 +
 .../reference/constructorOverloads3.js        |  1 +
 .../reference/declFileGenericType2.js         |  2 +
 .../reference/decoratorOnClassConstructor2.js |  1 +
 .../reference/decoratorOnClassConstructor3.js |  1 +
 ...derivedClassConstructorWithoutSuperCall.js |  4 ++
 .../derivedClassOverridesPrivateFunction1.js  |  1 +
 .../derivedClassOverridesProtectedMembers.js  |  1 +
 .../derivedClassOverridesProtectedMembers2.js |  1 +
 .../derivedClassOverridesProtectedMembers3.js | 10 ++++
 .../derivedClassOverridesPublicMembers.js     |  1 +
 .../derivedClassParameterProperties.js        | 10 ++++
 ...dClassSuperCallsInNonConstructorMembers.js |  1 +
 .../derivedClassSuperCallsWithThisArg.js      |  4 ++
 .../derivedClassWithoutExplicitConstructor.js |  2 +
 ...derivedClassWithoutExplicitConstructor2.js |  2 +
 ...derivedClassWithoutExplicitConstructor3.js |  4 ++
 .../destructuringParameterDeclaration5.js     |  2 +
 ...BeforeEmitParameterPropertyDeclaration1.js |  1 +
 ...SuperCallBeforeEmitPropertyDeclaration1.js |  1 +
 ...arationAndParameterPropertyDeclaration1.js |  1 +
 tests/baselines/reference/errorSuperCalls.js  |  2 +
 .../reference/errorSuperPropertyAccess.js     |  2 +
 .../reference/es6ClassSuperCodegenBug.js      |  1 +
 tests/baselines/reference/es6ClassTest.js     |  1 +
 tests/baselines/reference/es6ClassTest2.js    |  1 +
 ...cClassPropertyInheritanceSpecialization.js |  1 +
 ...genericConstraintOnExtendedBuiltinTypes.js |  1 +
 ...enericConstraintOnExtendedBuiltinTypes2.js |  1 +
 ...ericRecursiveImplicitConstructorErrors3.js |  1 +
 .../reference/genericTypeConstraints.js       |  1 +
 .../illegalSuperCallsInConstructor.js         |  1 +
 .../interfaceExtendsClassWithPrivate2.js      |  2 +
 tests/baselines/reference/lift.js             |  1 +
 .../missingPropertiesOfClassExpression.js     |  1 +
 ...objectCreationOfElementAccessExpression.js |  6 +++
 tests/baselines/reference/optionalMethods.js  |  1 +
 .../reference/optionalParamArgsTest.js        |  1 +
 .../reference/optionalParameterProperty.js    |  1 +
 .../overloadOnConstConstraintChecks4.js       |  1 +
 tests/baselines/reference/parserAstSpans1.js  |  2 +
 .../baselines/reference/parserRealSource10.js |  6 +++
 .../baselines/reference/parserRealSource11.js | 48 +++++++++++++++++++
 tests/baselines/reference/parserharness.js    |  3 ++
 .../privateInstanceMemberAccessibility.js     |  1 +
 .../privateStaticMemberAccessibility.js       |  1 +
 .../readonlyConstructorAssignment.js          |  3 ++
 .../reference/returnInConstructor1.js         |  2 +
 tests/baselines/reference/scopeTests.js       |  1 +
 ...sWithDefaultConstructorAndExtendsClause.js |  1 +
 ...hDefaultConstructorAndExtendsClause.js.map |  2 +-
 ...tConstructorAndExtendsClause.sourcemap.txt | 21 ++++----
 .../baselines/reference/staticInheritance.js  |  1 +
 tests/baselines/reference/staticPropSuper.js  |  4 ++
 .../reference/strictModeInConstructor.js      |  6 +++
 tests/baselines/reference/superAccess2.js     |  1 +
 .../reference/superCallArgsMustMatch.js       |  1 +
 .../reference/superCallAssignResult.js        |  1 +
 .../superCallBeforeThisAccessing1.js          |  1 +
 .../superCallBeforeThisAccessing2.js          |  1 +
 .../superCallBeforeThisAccessing3.js          |  1 +
 .../superCallBeforeThisAccessing4.js          |  2 +
 .../superCallBeforeThisAccessing5.js          |  1 +
 .../superCallBeforeThisAccessing6.js          |  1 +
 .../superCallBeforeThisAccessing7.js          |  1 +
 .../superCallBeforeThisAccessing8.js          |  1 +
 ...allFromClassThatDerivesFromGenericType1.js |  1 +
 ...allFromClassThatDerivesFromGenericType2.js |  1 +
 ...eButWithIncorrectNumberOfTypeArguments1.js |  1 +
 ...sFromGenericTypeButWithNoTypeArguments1.js |  1 +
 ...ivesNonGenericTypeButWithTypeArguments1.js |  1 +
 .../reference/superCallInNonStaticMethod.js   |  1 +
 .../superCallInsideClassDeclaration.js        |  2 +
 .../superCallInsideClassExpression.js         |  2 +
 .../superCallInsideObjectLiteralExpression.js |  1 +
 .../reference/superCallOutsideConstructor.js  |  1 +
 .../superCallParameterContextualTyping1.js    |  1 +
 .../superCallParameterContextualTyping2.js    |  1 +
 .../superCallParameterContextualTyping3.js    |  1 +
 tests/baselines/reference/superCalls.js       |  2 +
 .../reference/superCallsInConstructor.js      |  1 +
 tests/baselines/reference/superErrors.js      |  1 +
 .../reference/superInConstructorParam1.js     |  1 +
 tests/baselines/reference/superInLambdas.js   |  4 ++
 tests/baselines/reference/superNewCall1.js    |  1 +
 .../reference/superPropertyAccess1.js         |  1 +
 .../reference/superPropertyAccess2.js         |  1 +
 .../reference/superPropertyAccessNoError.js   |  1 +
 .../reference/superPropertyAccess_ES5.js      |  1 +
 .../superWithGenericSpecialization.js         |  1 +
 .../baselines/reference/superWithGenerics.js  |  1 +
 .../reference/superWithTypeArgument.js        |  1 +
 .../reference/superWithTypeArgument2.js       |  1 +
 .../reference/superWithTypeArgument3.js       |  1 +
 .../reference/targetTypeBaseCalls.js          |  1 +
 .../reference/thisInInvalidContexts.js        |  2 +
 .../thisInInvalidContextsExternalModule.js    |  2 +
 tests/baselines/reference/thisInSuperCall.js  |  3 ++
 tests/baselines/reference/thisInSuperCall1.js |  1 +
 tests/baselines/reference/thisInSuperCall2.js |  2 +
 tests/baselines/reference/thisInSuperCall3.js |  1 +
 .../baselines/reference/tsxDynamicTagName5.js |  1 +
 .../baselines/reference/tsxDynamicTagName7.js |  1 +
 .../baselines/reference/tsxDynamicTagName8.js |  1 +
 .../baselines/reference/tsxDynamicTagName9.js |  1 +
 .../reference/typeGuardOfFormThisMember.js    |  1 +
 .../typeGuardOfFormThisMemberErrors.js        |  1 +
 tests/baselines/reference/typeOfSuperCall.js  |  1 +
 .../baselines/reference/typeRelationships.js  |  1 +
 tests/baselines/reference/unknownSymbols1.js  |  1 +
 .../reference/unspecializedConstraints.js     |  3 ++
 .../reference/validUseOfThisInSuper.js        |  1 +
 .../reference/varArgsOnConstructorTypes.js    |  1 +
 157 files changed, 315 insertions(+), 11 deletions(-)

diff --git a/tests/baselines/reference/abstractProperty.js b/tests/baselines/reference/abstractProperty.js
index d9bfd5eb05f..292213ead53 100644
--- a/tests/baselines/reference/abstractProperty.js
+++ b/tests/baselines/reference/abstractProperty.js
@@ -39,6 +39,7 @@ var C = (function (_super) {
         _this = _super.apply(this, arguments) || this;
         _this.raw = "edge";
         _this.ro = "readonly please";
+        return _this;
     }
     Object.defineProperty(C.prototype, "prop", {
         get: function () { return "foo"; },
diff --git a/tests/baselines/reference/abstractPropertyNegative.js b/tests/baselines/reference/abstractPropertyNegative.js
index e94d9492fdb..28ada310ef4 100644
--- a/tests/baselines/reference/abstractPropertyNegative.js
+++ b/tests/baselines/reference/abstractPropertyNegative.js
@@ -60,6 +60,7 @@ var C = (function (_super) {
         var _this;
         _this = _super.apply(this, arguments) || this;
         _this.ro = "readonly please";
+        return _this;
     }
     Object.defineProperty(C.prototype, "concreteWithNoBody", {
         get: function () { },
@@ -81,6 +82,7 @@ var WrongTypePropertyImpl = (function (_super) {
         var _this;
         _this = _super.apply(this, arguments) || this;
         _this.num = "nope, wrong";
+        return _this;
     }
     return WrongTypePropertyImpl;
 }(WrongTypeProperty));
@@ -108,6 +110,7 @@ var WrongTypeAccessorImpl2 = (function (_super) {
         var _this;
         _this = _super.apply(this, arguments) || this;
         _this.num = "nope, wrong";
+        return _this;
     }
     return WrongTypeAccessorImpl2;
 }(WrongTypeAccessor));
diff --git a/tests/baselines/reference/accessOverriddenBaseClassMember1.js b/tests/baselines/reference/accessOverriddenBaseClassMember1.js
index b4c269b1e3b..65431a2f778 100644
--- a/tests/baselines/reference/accessOverriddenBaseClassMember1.js
+++ b/tests/baselines/reference/accessOverriddenBaseClassMember1.js
@@ -37,6 +37,7 @@ var ColoredPoint = (function (_super) {
         var _this;
         _this = _super.call(this, x, y) || this;
         _this.color = color;
+        return _this;
     }
     ColoredPoint.prototype.toString = function () {
         return _super.prototype.toString.call(this) + " color=" + this.color;
diff --git a/tests/baselines/reference/aliasUsageInTypeArgumentOfExtendsClause.js b/tests/baselines/reference/aliasUsageInTypeArgumentOfExtendsClause.js
index 462390d28f7..8af9c702654 100644
--- a/tests/baselines/reference/aliasUsageInTypeArgumentOfExtendsClause.js
+++ b/tests/baselines/reference/aliasUsageInTypeArgumentOfExtendsClause.js
@@ -68,6 +68,7 @@ var D = (function (_super) {
         var _this;
         _this = _super.apply(this, arguments) || this;
         _this.x = moduleA;
+        return _this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/arrowFunctionContexts.js b/tests/baselines/reference/arrowFunctionContexts.js
index bfd49be6bbf..660208cb0c1 100644
--- a/tests/baselines/reference/arrowFunctionContexts.js
+++ b/tests/baselines/reference/arrowFunctionContexts.js
@@ -118,6 +118,7 @@ var Derived = (function (_super) {
     function Derived() {
         var _this;
         _this = _super.call(this, function () { return _this; }) || this;
+        return _this;
     }
     return Derived;
 }(Base));
@@ -160,6 +161,7 @@ var M2;
         function Derived() {
             var _this;
             _this = _super.call(this, function () { return _this; }) || this;
+            return _this;
         }
         return Derived;
     }(Base));
diff --git a/tests/baselines/reference/assignmentLHSIsValue.js b/tests/baselines/reference/assignmentLHSIsValue.js
index 070c151ee51..52d14cbe536 100644
--- a/tests/baselines/reference/assignmentLHSIsValue.js
+++ b/tests/baselines/reference/assignmentLHSIsValue.js
@@ -121,6 +121,7 @@ var Derived = (function (_super) {
         var _this;
         _this = _super.call(this) || this;
         _super.prototype. = value;
+        return _this;
     }
     Derived.prototype.foo = function () { _super.prototype. = value; };
     Derived.sfoo = function () { _super. = value; };
diff --git a/tests/baselines/reference/autolift4.js b/tests/baselines/reference/autolift4.js
index b6afd28d429..0638efab0b3 100644
--- a/tests/baselines/reference/autolift4.js
+++ b/tests/baselines/reference/autolift4.js
@@ -46,6 +46,7 @@ var Point3D = (function (_super) {
         var _this;
         _this = _super.call(this, x, y) || this;
         _this.z = z;
+        return _this;
     }
     Point3D.prototype.getDist = function () {
         return Math.sqrt(this.x * this.x + this.y * this.y + this.z * this.m);
diff --git a/tests/baselines/reference/baseCheck.js b/tests/baselines/reference/baseCheck.js
index c3a2731b45d..832830ae864 100644
--- a/tests/baselines/reference/baseCheck.js
+++ b/tests/baselines/reference/baseCheck.js
@@ -45,6 +45,7 @@ var ELoc = (function (_super) {
     function ELoc(x) {
         var _this;
         _this = _super.call(this, 0, x) || this;
+        return _this;
     }
     return ELoc;
 }(C));
@@ -53,6 +54,7 @@ var ELocVar = (function (_super) {
     function ELocVar(x) {
         var _this;
         _this = _super.call(this, 0, loc) || this;
+        return _this;
     }
     ELocVar.prototype.m = function () {
         var loc = 10;
@@ -65,6 +67,7 @@ var D = (function (_super) {
         var _this;
         _this = _super.call(this, _this.z) || this;
         _this.z = z;
+        return _this;
     }
     return D;
 }(C)); // too few params
@@ -74,6 +77,7 @@ var E = (function (_super) {
         var _this;
         _this = _super.call(this, 0, _this.z) || this;
         _this.z = z;
+        return _this;
     }
     return E;
 }(C));
@@ -83,6 +87,7 @@ var F = (function (_super) {
         var _this;
         _this = _super.call(this, "hello", _this.z) || this;
         _this.z = z;
+        return _this;
     }
     return F;
 }(C)); // first param type
diff --git a/tests/baselines/reference/bases.js b/tests/baselines/reference/bases.js
index ff6a3262d45..6b73eb9556b 100644
--- a/tests/baselines/reference/bases.js
+++ b/tests/baselines/reference/bases.js
@@ -39,6 +39,7 @@ var C = (function (_super) {
         var _this;
         _this.x;
         any;
+        return _this;
     }
     return C;
 }(B));
diff --git a/tests/baselines/reference/bestCommonTypeOfTuple2.js b/tests/baselines/reference/bestCommonTypeOfTuple2.js
index 34deb346cbd..8213733b753 100644
--- a/tests/baselines/reference/bestCommonTypeOfTuple2.js
+++ b/tests/baselines/reference/bestCommonTypeOfTuple2.js
@@ -63,6 +63,7 @@ var D1 = (function (_super) {
         var _this;
         _this = _super.apply(this, arguments) || this;
         _this.i = "bar";
+        return _this;
     }
     return D1;
 }(C1));
diff --git a/tests/baselines/reference/callWithSpread.js b/tests/baselines/reference/callWithSpread.js
index 2149db744b0..48af58edf65 100644
--- a/tests/baselines/reference/callWithSpread.js
+++ b/tests/baselines/reference/callWithSpread.js
@@ -102,6 +102,7 @@ var D = (function (_super) {
         var _this;
         _this = _super.call(this, 1, 2) || this;
         _this = _super.apply(this, [1, 2].concat(a)) || this;
+        return _this;
     }
     D.prototype.foo = function () {
         _super.prototype.foo.call(this, 1, 2);
diff --git a/tests/baselines/reference/captureThisInSuperCall.js b/tests/baselines/reference/captureThisInSuperCall.js
index 0c36877d9dc..2d39722548d 100644
--- a/tests/baselines/reference/captureThisInSuperCall.js
+++ b/tests/baselines/reference/captureThisInSuperCall.js
@@ -24,6 +24,7 @@ var B = (function (_super) {
     function B() {
         var _this;
         _this = _super.call(this, { test: function () { return _this.someMethod(); } }) || this;
+        return _this;
     }
     B.prototype.someMethod = function () { };
     return B;
diff --git a/tests/baselines/reference/checkForObjectTooStrict.js b/tests/baselines/reference/checkForObjectTooStrict.js
index 48825a01a67..8c0cfc104d2 100644
--- a/tests/baselines/reference/checkForObjectTooStrict.js
+++ b/tests/baselines/reference/checkForObjectTooStrict.js
@@ -51,6 +51,7 @@ var Bar = (function (_super) {
     function Bar() {
         var _this;
         _this = _super.call(this) || this;
+        return _this;
     }
     return Bar;
 }(Foo.Object));
@@ -59,6 +60,7 @@ var Baz = (function (_super) {
     function Baz() {
         var _this;
         _this = _super.call(this) || this;
+        return _this;
     }
     return Baz;
 }(Object));
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing1.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing1.js
index 35e00c36621..a54f82ab9fa 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing1.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing1.js
@@ -29,6 +29,7 @@ var Derived = (function (_super) {
         _this;
         _this.x = 10;
         var that = _this;
+        return _this;
     }
     return Derived;
 }(Based));
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing2.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing2.js
index b49c1aab774..95b34f27b68 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing2.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing2.js
@@ -29,6 +29,7 @@ var Derived = (function (_super) {
         _this = _super.call(this) || this;
         _this.x = 10;
         var that = _this;
+        return _this;
     }
     return Derived;
 }(Based));
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing3.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing3.js
index 70600bb03a9..0e882f71fdb 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing3.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing3.js
@@ -39,6 +39,7 @@ var Derived = (function (_super) {
         _this = _super.call(this) || this;
         _this.x = 10;
         var that = _this;
+        return _this;
     }
     return Derived;
 }(Based));
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing4.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing4.js
index 95e0062b087..00f2ed22fbf 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing4.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing4.js
@@ -47,6 +47,7 @@ var Derived = (function (_super) {
         _this = _super.call(this) || this;
         _this.x = 10;
         var that = _this;
+        return _this;
     }
     return Derived;
 }(Based));
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing5.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing5.js
index 1c77b2e7c78..e365678ee0c 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing5.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing5.js
@@ -27,6 +27,7 @@ var Derived = (function (_super) {
     function Derived() {
         var _this;
         _this = _super.call(this, _this.x) || this;
+        return _this;
     }
     return Derived;
 }(Based));
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing6.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing6.js
index 15fcbff4c89..cc8912230ab 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing6.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing6.js
@@ -31,6 +31,7 @@ var Super = (function (_super) {
         var _this;
         (function () { return _this; }); // No Error
         _this = _super.call(this) || this;
+        return _this;
     }
     return Super;
 }(Base));
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing7.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing7.js
index 0cade04664d..7ba43de005b 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing7.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing7.js
@@ -25,6 +25,7 @@ var Super = (function (_super) {
     function Super() {
         var _this;
         _this = _super.call(this, (function () { return _this; })) || this; // No error
+        return _this;
     }
     return Super;
 }(Base));
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing8.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing8.js
index a280c0d6ca6..25a480b9b57 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing8.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing8.js
@@ -31,6 +31,7 @@ var Super = (function (_super) {
         var _this;
         var that = _this;
         _this = _super.call(this) || this;
+        return _this;
     }
     return Super;
 }(Base));
diff --git a/tests/baselines/reference/classConstructorAccessibility2.js b/tests/baselines/reference/classConstructorAccessibility2.js
index 9d1ebdd9d9a..8a81d469fb8 100644
--- a/tests/baselines/reference/classConstructorAccessibility2.js
+++ b/tests/baselines/reference/classConstructorAccessibility2.js
@@ -80,6 +80,7 @@ var DerivedA = (function (_super) {
         var _this;
         _this = _super.call(this, x) || this;
         _this.x = x;
+        return _this;
     }
     DerivedA.prototype.createInstance = function () { new DerivedA(5); };
     DerivedA.prototype.createBaseInstance = function () { new BaseA(6); };
@@ -92,6 +93,7 @@ var DerivedB = (function (_super) {
         var _this;
         _this = _super.call(this, x) || this;
         _this.x = x;
+        return _this;
     }
     DerivedB.prototype.createInstance = function () { new DerivedB(7); };
     DerivedB.prototype.createBaseInstance = function () { new BaseB(8); }; // ok
@@ -104,6 +106,7 @@ var DerivedC = (function (_super) {
         var _this;
         _this = _super.call(this, x) || this;
         _this.x = x;
+        return _this;
     }
     DerivedC.prototype.createInstance = function () { new DerivedC(9); };
     DerivedC.prototype.createBaseInstance = function () { new BaseC(10); }; // error
diff --git a/tests/baselines/reference/classConstructorParametersAccessibility.js b/tests/baselines/reference/classConstructorParametersAccessibility.js
index 066c724b60f..214815f4976 100644
--- a/tests/baselines/reference/classConstructorParametersAccessibility.js
+++ b/tests/baselines/reference/classConstructorParametersAccessibility.js
@@ -62,6 +62,7 @@ var Derived = (function (_super) {
         var _this;
         _this = _super.call(this, p) || this;
         _this.p; // OK
+        return _this;
     }
     return Derived;
 }(C3));
diff --git a/tests/baselines/reference/classConstructorParametersAccessibility2.js b/tests/baselines/reference/classConstructorParametersAccessibility2.js
index b8050435171..7c714aa4c03 100644
--- a/tests/baselines/reference/classConstructorParametersAccessibility2.js
+++ b/tests/baselines/reference/classConstructorParametersAccessibility2.js
@@ -62,6 +62,7 @@ var Derived = (function (_super) {
         var _this;
         _this = _super.call(this, p) || this;
         _this.p; // OK
+        return _this;
     }
     return Derived;
 }(C3));
diff --git a/tests/baselines/reference/classConstructorParametersAccessibility3.js b/tests/baselines/reference/classConstructorParametersAccessibility3.js
index 9e0c0264fd9..275f3920538 100644
--- a/tests/baselines/reference/classConstructorParametersAccessibility3.js
+++ b/tests/baselines/reference/classConstructorParametersAccessibility3.js
@@ -32,6 +32,7 @@ var Derived = (function (_super) {
         _this = _super.call(this, p) || this;
         _this.p = p;
         _this.p; // OK
+        return _this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/classExpression3.js b/tests/baselines/reference/classExpression3.js
index e0ba9c349e7..3c53d728233 100644
--- a/tests/baselines/reference/classExpression3.js
+++ b/tests/baselines/reference/classExpression3.js
@@ -18,6 +18,7 @@ var C = (function (_super) {
         var _this;
         _this = _super.apply(this, arguments) || this;
         _this.c = 3;
+        return _this;
     }
     return class_1;
 }((function (_super) {
@@ -26,6 +27,7 @@ var C = (function (_super) {
         var _this;
         _this = _super.apply(this, arguments) || this;
         _this.b = 2;
+        return _this;
     }
     return class_2;
 }((function () {
diff --git a/tests/baselines/reference/classExtendingClassLikeType.js b/tests/baselines/reference/classExtendingClassLikeType.js
index 2d91befc172..32d7fff0cbd 100644
--- a/tests/baselines/reference/classExtendingClassLikeType.js
+++ b/tests/baselines/reference/classExtendingClassLikeType.js
@@ -80,6 +80,7 @@ var D1 = (function (_super) {
         _this = _super.call(this, "abc", "def") || this;
         _this.x = "x";
         _this.y = "y";
+        return _this;
     }
     return D1;
 }(getBase()));
@@ -91,6 +92,7 @@ var D2 = (function (_super) {
         _this = _super.call(this, 10, 20) || this;
         _this.x = 1;
         _this.y = 2;
+        return _this;
     }
     return D2;
 }(getBase()));
@@ -101,6 +103,7 @@ var D3 = (function (_super) {
         _this = _super.call(this, "abc", 42) || this;
         _this.x = "x";
         _this.y = 2;
+        return _this;
     }
     return D3;
 }(getBase()));
diff --git a/tests/baselines/reference/classExtendsNull.js b/tests/baselines/reference/classExtendsNull.js
index 3ff1c92a56e..301dee7f705 100644
--- a/tests/baselines/reference/classExtendsNull.js
+++ b/tests/baselines/reference/classExtendsNull.js
@@ -24,6 +24,7 @@ var C = (function (_super) {
         var _this;
         _this = _super.call(this) || this;
         return Object.create(null);
+        return _this;
     }
     return C;
 }(null));
@@ -32,6 +33,7 @@ var D = (function (_super) {
     function D() {
         var _this;
         return Object.create(null);
+        return _this;
     }
     return D;
 }(null));
diff --git a/tests/baselines/reference/classSideInheritance2.js b/tests/baselines/reference/classSideInheritance2.js
index c5c506d1af6..1af6b6f846c 100644
--- a/tests/baselines/reference/classSideInheritance2.js
+++ b/tests/baselines/reference/classSideInheritance2.js
@@ -31,6 +31,7 @@ var SubText = (function (_super) {
     function SubText(text, span) {
         var _this;
         _this = _super.call(this) || this;
+        return _this;
     }
     return SubText;
 }(TextBase));
diff --git a/tests/baselines/reference/classSideInheritance3.js b/tests/baselines/reference/classSideInheritance3.js
index 4751e0e8d6e..fda7b0b0848 100644
--- a/tests/baselines/reference/classSideInheritance3.js
+++ b/tests/baselines/reference/classSideInheritance3.js
@@ -36,6 +36,7 @@ var B = (function (_super) {
         var _this;
         _this = _super.call(this, x) || this;
         _this.data = data;
+        return _this;
     }
     return B;
 }(A));
@@ -44,6 +45,7 @@ var C = (function (_super) {
     function C(x) {
         var _this;
         _this = _super.call(this, x) || this;
+        return _this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/classUpdateTests.js b/tests/baselines/reference/classUpdateTests.js
index d334e1c7f66..2d7ecc3c190 100644
--- a/tests/baselines/reference/classUpdateTests.js
+++ b/tests/baselines/reference/classUpdateTests.js
@@ -160,6 +160,7 @@ var E = (function (_super) {
         var _this;
         _this = _super.apply(this, arguments) || this;
         _this.p1 = 0;
+        return _this;
     }
     return E;
 }(D));
@@ -167,6 +168,7 @@ var F = (function (_super) {
     __extends(F, _super);
     function F() {
         var _this;
+        return _this;
     } // ERROR - super call required
     return F;
 }(E));
@@ -176,6 +178,7 @@ var G = (function (_super) {
         var _this;
         _this = _super.call(this) || this;
         _this.p1 = 0;
+        return _this;
     } // NO ERROR
     return G;
 }(D));
@@ -190,6 +193,7 @@ var I = (function (_super) {
     function I() {
         var _this;
         _this = _super.call(this) || this;
+        return _this;
     } // ERROR - no super call allowed
     return I;
 }(Object));
@@ -199,6 +203,7 @@ var J = (function (_super) {
         var _this;
         _this = _super.call(this) || this; // NO ERROR
         _this.p1 = p1;
+        return _this;
     }
     return J;
 }(G));
@@ -209,6 +214,7 @@ var K = (function (_super) {
         _this.p1 = p1;
         var i = 0;
         _this = _super.call(this) || this;
+        return _this;
     }
     return K;
 }(G));
@@ -218,6 +224,7 @@ var L = (function (_super) {
         var _this;
         _this = _super.call(this) || this; // NO ERROR
         _this.p1 = p1;
+        return _this;
     }
     return L;
 }(G));
@@ -228,6 +235,7 @@ var M = (function (_super) {
         _this.p1 = p1;
         var i = 0;
         _this = _super.call(this) || this;
+        return _this;
     }
     return M;
 }(G));
diff --git a/tests/baselines/reference/collisionSuperAndLocalFunctionInConstructor.js b/tests/baselines/reference/collisionSuperAndLocalFunctionInConstructor.js
index b961b8fa4a5..5f2a5e89301 100644
--- a/tests/baselines/reference/collisionSuperAndLocalFunctionInConstructor.js
+++ b/tests/baselines/reference/collisionSuperAndLocalFunctionInConstructor.js
@@ -46,6 +46,7 @@ var b = (function (_super) {
         _this = _super.call(this) || this;
         function _super() {
         }
+        return _this;
     }
     return b;
 }(Foo));
@@ -58,6 +59,7 @@ var c = (function (_super) {
             function _super() {
             }
         };
+        return _this;
     }
     return c;
 }(Foo));
diff --git a/tests/baselines/reference/collisionSuperAndLocalFunctionInProperty.js b/tests/baselines/reference/collisionSuperAndLocalFunctionInProperty.js
index e3d834dd1d4..a6893c6a57a 100644
--- a/tests/baselines/reference/collisionSuperAndLocalFunctionInProperty.js
+++ b/tests/baselines/reference/collisionSuperAndLocalFunctionInProperty.js
@@ -48,6 +48,7 @@ var b = (function (_super) {
                 }
             }
         };
+        return _this;
     }
     return b;
 }(Foo));
diff --git a/tests/baselines/reference/collisionSuperAndLocalVarInConstructor.js b/tests/baselines/reference/collisionSuperAndLocalVarInConstructor.js
index b3ef3000762..d799c783503 100644
--- a/tests/baselines/reference/collisionSuperAndLocalVarInConstructor.js
+++ b/tests/baselines/reference/collisionSuperAndLocalVarInConstructor.js
@@ -39,6 +39,7 @@ var b = (function (_super) {
         var _this;
         _this = _super.call(this) || this;
         var _super = 10; // Should be error 
+        return _this;
     }
     return b;
 }(Foo));
@@ -50,6 +51,7 @@ var c = (function (_super) {
         var x = function () {
             var _super = 10; // Should be error
         };
+        return _this;
     }
     return c;
 }(Foo));
diff --git a/tests/baselines/reference/collisionSuperAndLocalVarInProperty.js b/tests/baselines/reference/collisionSuperAndLocalVarInProperty.js
index e7cb0e613cc..4bb4f6a5a8b 100644
--- a/tests/baselines/reference/collisionSuperAndLocalVarInProperty.js
+++ b/tests/baselines/reference/collisionSuperAndLocalVarInProperty.js
@@ -46,6 +46,7 @@ var b = (function (_super) {
             }
         };
         _this._super = 10; // No error
+        return _this;
     }
     return b;
 }(Foo));
diff --git a/tests/baselines/reference/collisionSuperAndParameter.js b/tests/baselines/reference/collisionSuperAndParameter.js
index a60889888d6..6ed47a1b3c1 100644
--- a/tests/baselines/reference/collisionSuperAndParameter.js
+++ b/tests/baselines/reference/collisionSuperAndParameter.js
@@ -100,6 +100,7 @@ var Foo2 = (function (_super) {
             doStuff: function (_super) {
             }
         };
+        return _this;
     }
     Foo2.prototype.x = function () {
         var _this = this;
@@ -126,6 +127,7 @@ var Foo4 = (function (_super) {
     function Foo4(_super) {
         var _this;
         _this = _super.call(this) || this;
+        return _this;
     }
     Foo4.prototype.y = function (_super) {
         var _this = this;
diff --git a/tests/baselines/reference/collisionSuperAndPropertyNameAsConstuctorParameter.js b/tests/baselines/reference/collisionSuperAndPropertyNameAsConstuctorParameter.js
index 696f439a4b1..2d3709fa878 100644
--- a/tests/baselines/reference/collisionSuperAndPropertyNameAsConstuctorParameter.js
+++ b/tests/baselines/reference/collisionSuperAndPropertyNameAsConstuctorParameter.js
@@ -46,6 +46,7 @@ var b1 = (function (_super) {
     function b1(_super) {
         var _this;
         _this = _super.call(this) || this;
+        return _this;
     }
     return b1;
 }(a));
@@ -55,6 +56,7 @@ var b2 = (function (_super) {
         var _this;
         _this = _super.call(this) || this;
         _this._super = _super;
+        return _this;
     }
     return b2;
 }(a));
@@ -63,6 +65,7 @@ var b3 = (function (_super) {
     function b3(_super) {
         var _this;
         _this = _super.call(this) || this;
+        return _this;
     }
     return b3;
 }(a));
@@ -72,6 +75,7 @@ var b4 = (function (_super) {
         var _this;
         _this = _super.call(this) || this;
         _this._super = _super;
+        return _this;
     }
     return b4;
 }(a));
diff --git a/tests/baselines/reference/commentsInheritance.js b/tests/baselines/reference/commentsInheritance.js
index 860c0b90e48..370ee0d246c 100644
--- a/tests/baselines/reference/commentsInheritance.js
+++ b/tests/baselines/reference/commentsInheritance.js
@@ -229,6 +229,7 @@ var c3 = (function (_super) {
     function c3() {
         var _this;
         _this = _super.call(this, 10) || this;
+        return _this;
     }
     /** c3 f1*/
     c3.prototype.f1 = function () {
diff --git a/tests/baselines/reference/compoundAssignmentLHSIsValue.js b/tests/baselines/reference/compoundAssignmentLHSIsValue.js
index 2057d63b38f..dfbdf31c3d1 100644
--- a/tests/baselines/reference/compoundAssignmentLHSIsValue.js
+++ b/tests/baselines/reference/compoundAssignmentLHSIsValue.js
@@ -201,6 +201,7 @@ var Derived = (function (_super) {
         _this = _super.call(this) || this;
         _super.prototype. *= value;
         _super.prototype. += value;
+        return _this;
     }
     Derived.prototype.foo = function () {
         _super.prototype. *= value;
diff --git a/tests/baselines/reference/compoundExponentiationAssignmentLHSIsValue.js b/tests/baselines/reference/compoundExponentiationAssignmentLHSIsValue.js
index ef29163eda6..da670472b47 100644
--- a/tests/baselines/reference/compoundExponentiationAssignmentLHSIsValue.js
+++ b/tests/baselines/reference/compoundExponentiationAssignmentLHSIsValue.js
@@ -143,6 +143,7 @@ var Derived = (function (_super) {
         _this = _super.call(this) || this;
         (_a = _super.prototype). = Math.pow(_a., value);
         var _a;
+        return _this;
     }
     Derived.prototype.foo = function () {
         (_a = _super.prototype). = Math.pow(_a., value);
diff --git a/tests/baselines/reference/computedPropertyNames28_ES5.js b/tests/baselines/reference/computedPropertyNames28_ES5.js
index aaac258504c..8152394cbf8 100644
--- a/tests/baselines/reference/computedPropertyNames28_ES5.js
+++ b/tests/baselines/reference/computedPropertyNames28_ES5.js
@@ -29,6 +29,7 @@ var C = (function (_super) {
         var obj = (_a = {},
             _a[(_this = _super.call(this) || this, "prop")] = function () { },
             _a);
+        return _this;
         var _a;
     }
     return C;
diff --git a/tests/baselines/reference/computedPropertyNames30_ES5.js b/tests/baselines/reference/computedPropertyNames30_ES5.js
index 9fbe5f380ca..9f4a4ab51f9 100644
--- a/tests/baselines/reference/computedPropertyNames30_ES5.js
+++ b/tests/baselines/reference/computedPropertyNames30_ES5.js
@@ -40,6 +40,7 @@ var C = (function (_super) {
                 _a);
             var _a;
         });
+        return _this;
     }
     return C;
 }(Base));
diff --git a/tests/baselines/reference/constructorArgs.js b/tests/baselines/reference/constructorArgs.js
index 2c2838c97f9..c7939472a96 100644
--- a/tests/baselines/reference/constructorArgs.js
+++ b/tests/baselines/reference/constructorArgs.js
@@ -32,6 +32,7 @@ var Sub = (function (_super) {
         var _this;
         _this = _super.call(this, options.value) || this;
         _this.options = options;
+        return _this;
     }
     return Sub;
 }(Super));
diff --git a/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType2.js b/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType2.js
index a235e2555f3..4f70c7d7f35 100644
--- a/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType2.js
+++ b/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType2.js
@@ -49,6 +49,7 @@ var Derived = (function (_super) {
     function Derived(x) {
         var _this;
         _this = _super.call(this, x) || this;
+        return _this;
     }
     return Derived;
 }(Base));
@@ -59,6 +60,7 @@ var Derived2 = (function (_super) {
         var _this;
         _this = _super.call(this, x) || this;
         return 1;
+        return _this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/constructorOverloads2.js b/tests/baselines/reference/constructorOverloads2.js
index a0ed6d890d4..0041acb489e 100644
--- a/tests/baselines/reference/constructorOverloads2.js
+++ b/tests/baselines/reference/constructorOverloads2.js
@@ -42,6 +42,7 @@ var Foo = (function (_super) {
     function Foo(x, y) {
         var _this;
         _this = _super.call(this, x) || this;
+        return _this;
     }
     Foo.prototype.bar1 = function () { };
     return Foo;
diff --git a/tests/baselines/reference/constructorOverloads3.js b/tests/baselines/reference/constructorOverloads3.js
index 7bc7989f7a3..c0ae9b452f9 100644
--- a/tests/baselines/reference/constructorOverloads3.js
+++ b/tests/baselines/reference/constructorOverloads3.js
@@ -32,6 +32,7 @@ var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo(x, y) {
         var _this;
+        return _this;
     }
     Foo.prototype.bar1 = function () { };
     return Foo;
diff --git a/tests/baselines/reference/declFileGenericType2.js b/tests/baselines/reference/declFileGenericType2.js
index 50280b589b3..0e5351e69ea 100644
--- a/tests/baselines/reference/declFileGenericType2.js
+++ b/tests/baselines/reference/declFileGenericType2.js
@@ -60,6 +60,7 @@ var templa;
                 function AbstractElementController() {
                     var _this;
                     _this = _super.call(this) || this;
+                    return _this;
                 }
                 return AbstractElementController;
             }(templa.mvc.AbstractController));
@@ -82,6 +83,7 @@ var templa;
                         var _this;
                         _this = _super.call(this) || this;
                         _this._controllers = [];
+                        return _this;
                     }
                     return AbstractCompositeElementController;
                 }(templa.dom.mvc.AbstractElementController));
diff --git a/tests/baselines/reference/decoratorOnClassConstructor2.js b/tests/baselines/reference/decoratorOnClassConstructor2.js
index d50912fbeac..1f0b9b0d517 100644
--- a/tests/baselines/reference/decoratorOnClassConstructor2.js
+++ b/tests/baselines/reference/decoratorOnClassConstructor2.js
@@ -47,6 +47,7 @@ var C = (function (_super) {
     function C(prop) {
         var _this;
         _this = _super.call(this) || this;
+        return _this;
     }
     return C;
 }(_0_ts_1.base));
diff --git a/tests/baselines/reference/decoratorOnClassConstructor3.js b/tests/baselines/reference/decoratorOnClassConstructor3.js
index 6f37ad9dea1..9182cce66f4 100644
--- a/tests/baselines/reference/decoratorOnClassConstructor3.js
+++ b/tests/baselines/reference/decoratorOnClassConstructor3.js
@@ -50,6 +50,7 @@ var C = (function (_super) {
     function C(prop) {
         var _this;
         _this = _super.call(this) || this;
+        return _this;
     }
     return C;
 }(_0_1.base));
diff --git a/tests/baselines/reference/derivedClassConstructorWithoutSuperCall.js b/tests/baselines/reference/derivedClassConstructorWithoutSuperCall.js
index 58903b2ba57..e76f3445c8e 100644
--- a/tests/baselines/reference/derivedClassConstructorWithoutSuperCall.js
+++ b/tests/baselines/reference/derivedClassConstructorWithoutSuperCall.js
@@ -48,6 +48,7 @@ var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
         var _this;
+        return _this;
     }
     return Derived;
 }(Base));
@@ -61,6 +62,7 @@ var Derived2 = (function (_super) {
     function Derived2() {
         var _this;
         var r2 = function () { return _this = _super.call(this) || this; }; // error for misplaced super call (nested function)
+        return _this;
     }
     return Derived2;
 }(Base2));
@@ -69,6 +71,7 @@ var Derived3 = (function (_super) {
     function Derived3() {
         var _this;
         var r = function () { _this = _super.call(this) || this; }; // error
+        return _this;
     }
     return Derived3;
 }(Base2));
@@ -77,6 +80,7 @@ var Derived4 = (function (_super) {
     function Derived4() {
         var _this;
         var r = _this = _super.call(this) || this; // ok
+        return _this;
     }
     return Derived4;
 }(Base2));
diff --git a/tests/baselines/reference/derivedClassOverridesPrivateFunction1.js b/tests/baselines/reference/derivedClassOverridesPrivateFunction1.js
index 605ad6afa45..fd601ff2211 100644
--- a/tests/baselines/reference/derivedClassOverridesPrivateFunction1.js
+++ b/tests/baselines/reference/derivedClassOverridesPrivateFunction1.js
@@ -34,6 +34,7 @@ var DerivedClass = (function (_super) {
     function DerivedClass() {
         var _this;
         _this = _super.call(this) || this;
+        return _this;
     }
     DerivedClass.prototype._init = function () {
     };
diff --git a/tests/baselines/reference/derivedClassOverridesProtectedMembers.js b/tests/baselines/reference/derivedClassOverridesProtectedMembers.js
index d3e3fe5d4c9..12344c19915 100644
--- a/tests/baselines/reference/derivedClassOverridesProtectedMembers.js
+++ b/tests/baselines/reference/derivedClassOverridesProtectedMembers.js
@@ -68,6 +68,7 @@ var Derived = (function (_super) {
     function Derived(a) {
         var _this;
         _this = _super.call(this, x) || this;
+        return _this;
     }
     Derived.prototype.b = function (a) { };
     Object.defineProperty(Derived.prototype, "c", {
diff --git a/tests/baselines/reference/derivedClassOverridesProtectedMembers2.js b/tests/baselines/reference/derivedClassOverridesProtectedMembers2.js
index 1f43469596a..37be9e209ac 100644
--- a/tests/baselines/reference/derivedClassOverridesProtectedMembers2.js
+++ b/tests/baselines/reference/derivedClassOverridesProtectedMembers2.js
@@ -96,6 +96,7 @@ var Derived = (function (_super) {
     function Derived(a) {
         var _this;
         _this = _super.call(this, a) || this;
+        return _this;
     }
     Derived.prototype.b = function (a) { };
     Object.defineProperty(Derived.prototype, "c", {
diff --git a/tests/baselines/reference/derivedClassOverridesProtectedMembers3.js b/tests/baselines/reference/derivedClassOverridesProtectedMembers3.js
index d678f5ce59f..0836c9d7f41 100644
--- a/tests/baselines/reference/derivedClassOverridesProtectedMembers3.js
+++ b/tests/baselines/reference/derivedClassOverridesProtectedMembers3.js
@@ -105,6 +105,7 @@ var Derived1 = (function (_super) {
     function Derived1(a) {
         var _this;
         _this = _super.call(this, a) || this;
+        return _this;
     }
     return Derived1;
 }(Base));
@@ -113,6 +114,7 @@ var Derived2 = (function (_super) {
     function Derived2(a) {
         var _this;
         _this = _super.call(this, a) || this;
+        return _this;
     }
     Derived2.prototype.b = function (a) { };
     return Derived2;
@@ -122,6 +124,7 @@ var Derived3 = (function (_super) {
     function Derived3(a) {
         var _this;
         _this = _super.call(this, a) || this;
+        return _this;
     }
     Object.defineProperty(Derived3.prototype, "c", {
         get: function () { return x; },
@@ -135,6 +138,7 @@ var Derived4 = (function (_super) {
     function Derived4(a) {
         var _this;
         _this = _super.call(this, a) || this;
+        return _this;
     }
     Object.defineProperty(Derived4.prototype, "c", {
         set: function (v) { },
@@ -148,6 +152,7 @@ var Derived5 = (function (_super) {
     function Derived5(a) {
         var _this;
         _this = _super.call(this, a) || this;
+        return _this;
     }
     return Derived5;
 }(Base));
@@ -156,6 +161,7 @@ var Derived6 = (function (_super) {
     function Derived6(a) {
         var _this;
         _this = _super.call(this, a) || this;
+        return _this;
     }
     return Derived6;
 }(Base));
@@ -164,6 +170,7 @@ var Derived7 = (function (_super) {
     function Derived7(a) {
         var _this;
         _this = _super.call(this, a) || this;
+        return _this;
     }
     Derived7.s = function (a) { };
     return Derived7;
@@ -173,6 +180,7 @@ var Derived8 = (function (_super) {
     function Derived8(a) {
         var _this;
         _this = _super.call(this, a) || this;
+        return _this;
     }
     Object.defineProperty(Derived8, "t", {
         get: function () { return x; },
@@ -186,6 +194,7 @@ var Derived9 = (function (_super) {
     function Derived9(a) {
         var _this;
         _this = _super.call(this, a) || this;
+        return _this;
     }
     Object.defineProperty(Derived9, "t", {
         set: function (v) { },
@@ -199,6 +208,7 @@ var Derived10 = (function (_super) {
     function Derived10(a) {
         var _this;
         _this = _super.call(this, a) || this;
+        return _this;
     }
     return Derived10;
 }(Base));
diff --git a/tests/baselines/reference/derivedClassOverridesPublicMembers.js b/tests/baselines/reference/derivedClassOverridesPublicMembers.js
index 7839398551d..8d0375ab13a 100644
--- a/tests/baselines/reference/derivedClassOverridesPublicMembers.js
+++ b/tests/baselines/reference/derivedClassOverridesPublicMembers.js
@@ -94,6 +94,7 @@ var Derived = (function (_super) {
     function Derived(a) {
         var _this;
         _this = _super.call(this, x) || this;
+        return _this;
     }
     Derived.prototype.b = function (a) { };
     Object.defineProperty(Derived.prototype, "c", {
diff --git a/tests/baselines/reference/derivedClassParameterProperties.js b/tests/baselines/reference/derivedClassParameterProperties.js
index 658e56fb098..f623653d6fa 100644
--- a/tests/baselines/reference/derivedClassParameterProperties.js
+++ b/tests/baselines/reference/derivedClassParameterProperties.js
@@ -112,6 +112,7 @@ var Derived = (function (_super) {
         var _this;
         var a = 1;
         _this = _super.call(this) || this; // ok
+        return _this;
     }
     return Derived;
 }(Base));
@@ -122,6 +123,7 @@ var Derived2 = (function (_super) {
         _this.y = y;
         var a = 1;
         _this = _super.call(this) || this; // error
+        return _this;
     }
     return Derived2;
 }(Base));
@@ -132,6 +134,7 @@ var Derived3 = (function (_super) {
         _this = _super.call(this) || this; // ok
         _this.y = y;
         var a = 1;
+        return _this;
     }
     return Derived3;
 }(Base));
@@ -142,6 +145,7 @@ var Derived4 = (function (_super) {
         _this.a = 1;
         var b = 2;
         _this = _super.call(this) || this; // error
+        return _this;
     }
     return Derived4;
 }(Base));
@@ -152,6 +156,7 @@ var Derived5 = (function (_super) {
         _this = _super.call(this) || this; // ok
         _this.a = 1;
         var b = 2;
+        return _this;
     }
     return Derived5;
 }(Base));
@@ -162,6 +167,7 @@ var Derived6 = (function (_super) {
         _this.a = 1;
         var b = 2;
         _this = _super.call(this) || this; // error: "super" has to be called before "this" accessing
+        return _this;
     }
     return Derived6;
 }(Base));
@@ -173,6 +179,7 @@ var Derived7 = (function (_super) {
         _this.a = 3;
         _this.b = 3;
         _this = _super.call(this) || this; // error
+        return _this;
     }
     return Derived7;
 }(Base));
@@ -184,6 +191,7 @@ var Derived8 = (function (_super) {
         _this.a = 1;
         _this.a = 3;
         _this.b = 3;
+        return _this;
     }
     return Derived8;
 }(Base));
@@ -201,6 +209,7 @@ var Derived9 = (function (_super) {
         _this.a = 3;
         _this.b = 3;
         _this = _super.call(this) || this; // error
+        return _this;
     }
     return Derived9;
 }(Base2));
@@ -212,6 +221,7 @@ var Derived10 = (function (_super) {
         _this.a = 1;
         _this.a = 3;
         _this.b = 3;
+        return _this;
     }
     return Derived10;
 }(Base2));
diff --git a/tests/baselines/reference/derivedClassSuperCallsInNonConstructorMembers.js b/tests/baselines/reference/derivedClassSuperCallsInNonConstructorMembers.js
index 6b06204b8e9..e3bbf2699c5 100644
--- a/tests/baselines/reference/derivedClassSuperCallsInNonConstructorMembers.js
+++ b/tests/baselines/reference/derivedClassSuperCallsInNonConstructorMembers.js
@@ -49,6 +49,7 @@ var Derived = (function (_super) {
         var _this;
         _this = _super.apply(this, arguments) || this;
         _this.a = _this = _super.call(this) || this;
+        return _this;
     }
     Derived.prototype.b = function () {
         _this = _super.call(this) || this;
diff --git a/tests/baselines/reference/derivedClassSuperCallsWithThisArg.js b/tests/baselines/reference/derivedClassSuperCallsWithThisArg.js
index e73d0041206..102944889bd 100644
--- a/tests/baselines/reference/derivedClassSuperCallsWithThisArg.js
+++ b/tests/baselines/reference/derivedClassSuperCallsWithThisArg.js
@@ -44,6 +44,7 @@ var Derived = (function (_super) {
     function Derived() {
         var _this;
         _this = _super.call(this, _this) || this; // ok
+        return _this;
     }
     return Derived;
 }(Base));
@@ -53,6 +54,7 @@ var Derived2 = (function (_super) {
         var _this;
         _this = _super.call(this, _this) || this; // error
         _this.a = a;
+        return _this;
     }
     return Derived2;
 }(Base));
@@ -62,6 +64,7 @@ var Derived3 = (function (_super) {
         var _this;
         _this = _super.call(this, function () { return _this; }) || this; // error
         _this.a = a;
+        return _this;
     }
     return Derived3;
 }(Base));
@@ -71,6 +74,7 @@ var Derived4 = (function (_super) {
         var _this;
         _this = _super.call(this, function () { return this; }) || this; // ok
         _this.a = a;
+        return _this;
     }
     return Derived4;
 }(Base));
diff --git a/tests/baselines/reference/derivedClassWithoutExplicitConstructor.js b/tests/baselines/reference/derivedClassWithoutExplicitConstructor.js
index cc260f09499..f5eb3d22360 100644
--- a/tests/baselines/reference/derivedClassWithoutExplicitConstructor.js
+++ b/tests/baselines/reference/derivedClassWithoutExplicitConstructor.js
@@ -45,6 +45,7 @@ var Derived = (function (_super) {
         _this = _super.apply(this, arguments) || this;
         _this.x = 1;
         _this.y = 'hello';
+        return _this;
     }
     return Derived;
 }(Base));
@@ -63,6 +64,7 @@ var D = (function (_super) {
         _this = _super.apply(this, arguments) || this;
         _this.x = 2;
         _this.y = null;
+        return _this;
     }
     return D;
 }(Base2));
diff --git a/tests/baselines/reference/derivedClassWithoutExplicitConstructor2.js b/tests/baselines/reference/derivedClassWithoutExplicitConstructor2.js
index d3711ec27c0..5ad20389230 100644
--- a/tests/baselines/reference/derivedClassWithoutExplicitConstructor2.js
+++ b/tests/baselines/reference/derivedClassWithoutExplicitConstructor2.js
@@ -53,6 +53,7 @@ var Derived = (function (_super) {
         _this = _super.apply(this, arguments) || this;
         _this.x = 1;
         _this.y = 'hello';
+        return _this;
     }
     return Derived;
 }(Base));
@@ -73,6 +74,7 @@ var D = (function (_super) {
         _this = _super.apply(this, arguments) || this;
         _this.x = 2;
         _this.y = null;
+        return _this;
     }
     return D;
 }(Base2));
diff --git a/tests/baselines/reference/derivedClassWithoutExplicitConstructor3.js b/tests/baselines/reference/derivedClassWithoutExplicitConstructor3.js
index 14f9fdf88af..d0e5f22d4f3 100644
--- a/tests/baselines/reference/derivedClassWithoutExplicitConstructor3.js
+++ b/tests/baselines/reference/derivedClassWithoutExplicitConstructor3.js
@@ -67,6 +67,7 @@ var Derived = (function (_super) {
         _this = _super.call(this, 2) || this;
         _this.b = '';
         _this.b = y;
+        return _this;
     }
     return Derived;
 }(Base));
@@ -77,6 +78,7 @@ var Derived2 = (function (_super) {
         _this = _super.apply(this, arguments) || this;
         _this.x = 1;
         _this.y = 'hello';
+        return _this;
     }
     return Derived2;
 }(Derived));
@@ -96,6 +98,7 @@ var D = (function (_super) {
         _this = _super.call(this, 2) || this;
         _this.b = null;
         _this.b = y;
+        return _this;
     }
     return D;
 }(Base));
@@ -106,6 +109,7 @@ var D2 = (function (_super) {
         _this = _super.apply(this, arguments) || this;
         _this.x = 2;
         _this.y = null;
+        return _this;
     }
     return D2;
 }(D));
diff --git a/tests/baselines/reference/destructuringParameterDeclaration5.js b/tests/baselines/reference/destructuringParameterDeclaration5.js
index a1f109ed49e..8c35b9044a1 100644
--- a/tests/baselines/reference/destructuringParameterDeclaration5.js
+++ b/tests/baselines/reference/destructuringParameterDeclaration5.js
@@ -67,6 +67,7 @@ var SubClass = (function (_super) {
     function SubClass() {
         var _this;
         _this = _super.call(this) || this;
+        return _this;
     }
     return SubClass;
 }(Class));
@@ -80,6 +81,7 @@ var SubD = (function (_super) {
     function SubD() {
         var _this;
         _this = _super.call(this) || this;
+        return _this;
     }
     return SubD;
 }(D));
diff --git a/tests/baselines/reference/emitSuperCallBeforeEmitParameterPropertyDeclaration1.js b/tests/baselines/reference/emitSuperCallBeforeEmitParameterPropertyDeclaration1.js
index 60fa8e32c1e..b95263464a7 100644
--- a/tests/baselines/reference/emitSuperCallBeforeEmitParameterPropertyDeclaration1.js
+++ b/tests/baselines/reference/emitSuperCallBeforeEmitParameterPropertyDeclaration1.js
@@ -33,6 +33,7 @@ var B = (function (_super) {
         'someStringForEgngInject';
         _this = _super.call(this) || this;
         _this.x = x;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclaration1.js b/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclaration1.js
index abef8394924..f078c448b75 100644
--- a/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclaration1.js
+++ b/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclaration1.js
@@ -35,6 +35,7 @@ var B = (function (_super) {
         'someStringForEgngInject';
         _this = _super.call(this) || this;
         _this.blub = 12;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclarationAndParameterPropertyDeclaration1.js b/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclarationAndParameterPropertyDeclaration1.js
index 0f36d9d9115..e64af9ef862 100644
--- a/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclarationAndParameterPropertyDeclaration1.js
+++ b/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclarationAndParameterPropertyDeclaration1.js
@@ -34,6 +34,7 @@ var B = (function (_super) {
         _this = _super.call(this) || this;
         _this.x = x;
         _this.blah = 2;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/errorSuperCalls.js b/tests/baselines/reference/errorSuperCalls.js
index 4f54781deb9..864bc19a344 100644
--- a/tests/baselines/reference/errorSuperCalls.js
+++ b/tests/baselines/reference/errorSuperCalls.js
@@ -135,6 +135,7 @@ var Derived = (function (_super) {
         var _this;
         _super.prototype..call(_this);
         _this = _super.call(this) || this;
+        return _this;
     }
     return Derived;
 }(Base));
@@ -150,6 +151,7 @@ var OtherDerived = (function (_super) {
         _this = _super.apply(this, arguments) || this;
         //super call in class member initializer of derived type
         _this.t = _this = _super.call(this) || this;
+        return _this;
     }
     OtherDerived.prototype.fn = function () {
         //super call in class member function of derived type
diff --git a/tests/baselines/reference/errorSuperPropertyAccess.js b/tests/baselines/reference/errorSuperPropertyAccess.js
index 18c98868e93..1b7c9a418fc 100644
--- a/tests/baselines/reference/errorSuperPropertyAccess.js
+++ b/tests/baselines/reference/errorSuperPropertyAccess.js
@@ -189,6 +189,7 @@ var SomeDerived1 = (function (_super) {
         var _this;
         _this = _super.call(this) || this;
         _super.prototype.publicMember = 1;
+        return _this;
     }
     SomeDerived1.prototype.fn = function () {
         var x = _super.prototype.publicMember;
@@ -223,6 +224,7 @@ var SomeDerived2 = (function (_super) {
         var _this;
         _this = _super.call(this) || this;
         _super.prototype.privateMember = 1;
+        return _this;
     }
     SomeDerived2.prototype.fn = function () {
         var x = _super.prototype.privateMember;
diff --git a/tests/baselines/reference/es6ClassSuperCodegenBug.js b/tests/baselines/reference/es6ClassSuperCodegenBug.js
index 88000a12bbe..2eec250211e 100644
--- a/tests/baselines/reference/es6ClassSuperCodegenBug.js
+++ b/tests/baselines/reference/es6ClassSuperCodegenBug.js
@@ -35,6 +35,7 @@ var B = (function (_super) {
         else {
             _this = _super.call(this, 'a2', 'b2') || this;
         }
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/es6ClassTest.js b/tests/baselines/reference/es6ClassTest.js
index 4b2cb2c51b5..705915812be 100644
--- a/tests/baselines/reference/es6ClassTest.js
+++ b/tests/baselines/reference/es6ClassTest.js
@@ -111,6 +111,7 @@ var Foo = (function (_super) {
         _this.zoo = "zoo";
         _this.x = x;
         _this.gar = 5;
+        return _this;
     }
     Foo.prototype.bar = function () { return 0; };
     Foo.prototype.boo = function (x) { return x; };
diff --git a/tests/baselines/reference/es6ClassTest2.js b/tests/baselines/reference/es6ClassTest2.js
index ebf779f7bba..eec5d830e01 100644
--- a/tests/baselines/reference/es6ClassTest2.js
+++ b/tests/baselines/reference/es6ClassTest2.js
@@ -269,6 +269,7 @@ var SuperChild = (function (_super) {
     function SuperChild() {
         var _this;
         _this = _super.call(this, 1) || this;
+        return _this;
     }
     SuperChild.prototype.b = function () {
         _super.prototype.b.call(this, 'str');
diff --git a/tests/baselines/reference/genericClassPropertyInheritanceSpecialization.js b/tests/baselines/reference/genericClassPropertyInheritanceSpecialization.js
index 0cc1f5867a2..ccbac1d22b5 100644
--- a/tests/baselines/reference/genericClassPropertyInheritanceSpecialization.js
+++ b/tests/baselines/reference/genericClassPropertyInheritanceSpecialization.js
@@ -111,6 +111,7 @@ var PortalFx;
                     function Validator(message) {
                         var _this;
                         _this = _super.call(this, message) || this;
+                        return _this;
                     }
                     return Validator;
                 }(Portal.Controls.Validators.Validator));
diff --git a/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes.js b/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes.js
index 4581ecc31ec..246b9b76e3c 100644
--- a/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes.js
+++ b/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes.js
@@ -54,6 +54,7 @@ var EndGate;
             function NumberTween(from) {
                 var _this;
                 _this = _super.call(this, from) || this;
+                return _this;
             }
             return NumberTween;
         }(Tweening.Tween));
diff --git a/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes2.js b/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes2.js
index 8f1e9c8365f..e7744b28833 100644
--- a/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes2.js
+++ b/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes2.js
@@ -53,6 +53,7 @@ var EndGate;
             function NumberTween(from) {
                 var _this;
                 _this = _super.call(this, from) || this;
+                return _this;
             }
             return NumberTween;
         }(Tweening.Tween));
diff --git a/tests/baselines/reference/genericRecursiveImplicitConstructorErrors3.js b/tests/baselines/reference/genericRecursiveImplicitConstructorErrors3.js
index 49109e1aa5a..d22823b9f81 100644
--- a/tests/baselines/reference/genericRecursiveImplicitConstructorErrors3.js
+++ b/tests/baselines/reference/genericRecursiveImplicitConstructorErrors3.js
@@ -62,6 +62,7 @@ var TypeScript;
             var _this;
             _this = _super.apply(this, arguments) || this;
             _this._elementType = null;
+            return _this;
         }
         PullTypeSymbol.prototype.toString = function (scopeSymbol, useConstraintInName) {
             var s = this.getScopedNameEx(scopeSymbol, useConstraintInName).toString();
diff --git a/tests/baselines/reference/genericTypeConstraints.js b/tests/baselines/reference/genericTypeConstraints.js
index 761220ae11a..48ff00e5ac2 100644
--- a/tests/baselines/reference/genericTypeConstraints.js
+++ b/tests/baselines/reference/genericTypeConstraints.js
@@ -40,6 +40,7 @@ var BarExtended = (function (_super) {
     function BarExtended() {
         var _this;
         _this = _super.call(this) || this;
+        return _this;
     }
     return BarExtended;
 }(Bar));
diff --git a/tests/baselines/reference/illegalSuperCallsInConstructor.js b/tests/baselines/reference/illegalSuperCallsInConstructor.js
index 77f0a0a2b6b..868d53daad5 100644
--- a/tests/baselines/reference/illegalSuperCallsInConstructor.js
+++ b/tests/baselines/reference/illegalSuperCallsInConstructor.js
@@ -47,6 +47,7 @@ var Derived = (function (_super) {
                 _this = _super.call(this) || this;
             }
         };
+        return _this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/interfaceExtendsClassWithPrivate2.js b/tests/baselines/reference/interfaceExtendsClassWithPrivate2.js
index 3f205640f59..51c64f48f6c 100644
--- a/tests/baselines/reference/interfaceExtendsClassWithPrivate2.js
+++ b/tests/baselines/reference/interfaceExtendsClassWithPrivate2.js
@@ -43,6 +43,7 @@ var D = (function (_super) {
         _this = _super.apply(this, arguments) || this;
         _this.x = 2;
         _this.y = 3;
+        return _this;
     }
     D.prototype.foo = function (x) { return x; };
     D.prototype.other = function (x) { return x; };
@@ -55,6 +56,7 @@ var D2 = (function (_super) {
         var _this;
         _this = _super.apply(this, arguments) || this;
         _this.x = "";
+        return _this;
     }
     D2.prototype.foo = function (x) { return x; };
     D2.prototype.other = function (x) { return x; };
diff --git a/tests/baselines/reference/lift.js b/tests/baselines/reference/lift.js
index bfbf75b1731..a71f1c9065a 100644
--- a/tests/baselines/reference/lift.js
+++ b/tests/baselines/reference/lift.js
@@ -36,6 +36,7 @@ var C = (function (_super) {
         _this = _super.call(this, y) || this;
         var x = 10 + w;
         var ll = x * w;
+        return _this;
     }
     C.prototype.liftxyz = function () { return x + z + this.y; };
     C.prototype.liftxylocllz = function () { return x + z + this.y + this.ll; };
diff --git a/tests/baselines/reference/missingPropertiesOfClassExpression.js b/tests/baselines/reference/missingPropertiesOfClassExpression.js
index c1f4480241c..20252f37e61 100644
--- a/tests/baselines/reference/missingPropertiesOfClassExpression.js
+++ b/tests/baselines/reference/missingPropertiesOfClassExpression.js
@@ -17,6 +17,7 @@ var George = (function (_super) {
     function George() {
         var _this;
         _this = _super.call(this) || this;
+        return _this;
     }
     return George;
 }((function () {
diff --git a/tests/baselines/reference/objectCreationOfElementAccessExpression.js b/tests/baselines/reference/objectCreationOfElementAccessExpression.js
index 9543082fbd1..760454dd9a4 100644
--- a/tests/baselines/reference/objectCreationOfElementAccessExpression.js
+++ b/tests/baselines/reference/objectCreationOfElementAccessExpression.js
@@ -84,6 +84,7 @@ var MonsterFood = (function (_super) {
         var _this;
         _this = _super.call(this, name) || this;
         _this.flavor = flavor;
+        return _this;
     }
     return MonsterFood;
 }(Food));
@@ -93,6 +94,7 @@ var IceCream = (function (_super) {
         var _this;
         _this = _super.call(this, "Ice Cream", flavor) || this;
         _this.flavor = flavor;
+        return _this;
     }
     return IceCream;
 }(MonsterFood));
@@ -103,6 +105,7 @@ var Cookie = (function (_super) {
         _this = _super.call(this, "Cookie", flavor) || this;
         _this.flavor = flavor;
         _this.isGlutenFree = isGlutenFree;
+        return _this;
     }
     return Cookie;
 }(MonsterFood));
@@ -112,6 +115,7 @@ var PetFood = (function (_super) {
         var _this;
         _this = _super.call(this, name) || this;
         _this.whereToBuy = whereToBuy;
+        return _this;
     }
     return PetFood;
 }(Food));
@@ -121,6 +125,7 @@ var ExpensiveOrganicDogFood = (function (_super) {
         var _this;
         _this = _super.call(this, "Origen", whereToBuy) || this;
         _this.whereToBuy = whereToBuy;
+        return _this;
     }
     return ExpensiveOrganicDogFood;
 }(PetFood));
@@ -131,6 +136,7 @@ var ExpensiveOrganicCatFood = (function (_super) {
         _this = _super.call(this, "Nature's Logic", whereToBuy) || this;
         _this.whereToBuy = whereToBuy;
         _this.containsFish = containsFish;
+        return _this;
     }
     return ExpensiveOrganicCatFood;
 }(PetFood));
diff --git a/tests/baselines/reference/optionalMethods.js b/tests/baselines/reference/optionalMethods.js
index 1885c419fef..72df561227f 100644
--- a/tests/baselines/reference/optionalMethods.js
+++ b/tests/baselines/reference/optionalMethods.js
@@ -112,6 +112,7 @@ var Derived = (function (_super) {
         var _this;
         _this = _super.apply(this, arguments) || this;
         _this.a = 1;
+        return _this;
     }
     Derived.prototype.f = function () { return 1; };
     return Derived;
diff --git a/tests/baselines/reference/optionalParamArgsTest.js b/tests/baselines/reference/optionalParamArgsTest.js
index f53f0c74a54..258f05cbc85 100644
--- a/tests/baselines/reference/optionalParamArgsTest.js
+++ b/tests/baselines/reference/optionalParamArgsTest.js
@@ -164,6 +164,7 @@ var C2 = (function (_super) {
         var _this;
         if (v2 === void 0) { v2 = 6; }
         _this = _super.call(this, v2) || this;
+        return _this;
     }
     return C2;
 }(C1));
diff --git a/tests/baselines/reference/optionalParameterProperty.js b/tests/baselines/reference/optionalParameterProperty.js
index 44eb2a7aa56..ca78ad7286e 100644
--- a/tests/baselines/reference/optionalParameterProperty.js
+++ b/tests/baselines/reference/optionalParameterProperty.js
@@ -28,6 +28,7 @@ var D = (function (_super) {
         var _this;
         _this = _super.call(this) || this;
         _this.p = p;
+        return _this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/overloadOnConstConstraintChecks4.js b/tests/baselines/reference/overloadOnConstConstraintChecks4.js
index 22bacbdb0b4..360b38ce70c 100644
--- a/tests/baselines/reference/overloadOnConstConstraintChecks4.js
+++ b/tests/baselines/reference/overloadOnConstConstraintChecks4.js
@@ -30,6 +30,7 @@ var A = (function (_super) {
         var _this;
         _this = _super.apply(this, arguments) || this;
         _this.x = 1;
+        return _this;
     }
     return A;
 }(Z));
diff --git a/tests/baselines/reference/parserAstSpans1.js b/tests/baselines/reference/parserAstSpans1.js
index 365e640c150..799a17d47de 100644
--- a/tests/baselines/reference/parserAstSpans1.js
+++ b/tests/baselines/reference/parserAstSpans1.js
@@ -321,6 +321,7 @@ var c3 = (function (_super) {
         var _this;
         _this = _super.call(this, 10) || this;
         _this.p1 = _super.prototype.c2_p1;
+        return _this;
     }
     /** c3 f1*/
     c3.prototype.f1 = function () {
@@ -409,6 +410,7 @@ var c6 = (function (_super) {
         var _this;
         _this = _super.call(this) || this;
         _this.d = _super.prototype.b;
+        return _this;
     }
     return c6;
 }(c5));
diff --git a/tests/baselines/reference/parserRealSource10.js b/tests/baselines/reference/parserRealSource10.js
index c9f011704d0..88516c9a692 100644
--- a/tests/baselines/reference/parserRealSource10.js
+++ b/tests/baselines/reference/parserRealSource10.js
@@ -830,6 +830,7 @@ var TypeScript;
             _this = _super.call(this, TokenID.NumberLiteral) || this;
             _this.value = value;
             _this.hasEmptyFraction = hasEmptyFraction;
+            return _this;
         }
         NumberLiteralToken.prototype.getText = function () {
             return this.hasEmptyFraction ? this.value.toString() + ".0" : this.value.toString();
@@ -846,6 +847,7 @@ var TypeScript;
             var _this;
             _this = _super.call(this, TokenID.StringLiteral) || this;
             _this.value = value;
+            return _this;
         }
         StringLiteralToken.prototype.getText = function () {
             return this.value;
@@ -863,6 +865,7 @@ var TypeScript;
             _this = _super.call(this, TokenID.Identifier) || this;
             _this.value = value;
             _this.hasEscapeSequence = hasEscapeSequence;
+            return _this;
         }
         IdentifierToken.prototype.getText = function () {
             return this.value;
@@ -879,6 +882,7 @@ var TypeScript;
             var _this;
             _this = _super.call(this, tokenId) || this;
             _this.value = value;
+            return _this;
         }
         WhitespaceToken.prototype.getText = function () {
             return this.value;
@@ -899,6 +903,7 @@ var TypeScript;
             _this.startPos = startPos;
             _this.line = line;
             _this.endsLine = endsLine;
+            return _this;
         }
         CommentToken.prototype.getText = function () {
             return this.value;
@@ -915,6 +920,7 @@ var TypeScript;
             var _this;
             _this = _super.call(this, TokenID.RegularExpressionLiteral) || this;
             _this.regex = regex;
+            return _this;
         }
         RegularExpressionLiteralToken.prototype.getText = function () {
             return this.regex.toString();
diff --git a/tests/baselines/reference/parserRealSource11.js b/tests/baselines/reference/parserRealSource11.js
index 054608e9d19..fa112e51dad 100644
--- a/tests/baselines/reference/parserRealSource11.js
+++ b/tests/baselines/reference/parserRealSource11.js
@@ -2396,6 +2396,7 @@ var TypeScript;
             _this.preComments = null;
             _this.postComments = null;
             _this.isParenthesized = false;
+            return _this;
         }
         AST.prototype.isExpression = function () { return false; };
         AST.prototype.isStatementOrExpression = function () { return false; };
@@ -2547,6 +2548,7 @@ var TypeScript;
             _this = _super.call(this, NodeType.Error) || this;
             _this.minChar = min;
             _this.limChar = lim;
+            return _this;
         }
         return IncompleteAST;
     }(AST));
@@ -2558,6 +2560,7 @@ var TypeScript;
             _this = _super.call(this, NodeType.List) || this;
             _this.enclosingScope = null;
             _this.members = new AST[];
+            return _this;
         }
         ASTList.prototype.addToControlFlow = function (context) {
             var len = this.members.length;
@@ -2629,6 +2632,7 @@ var TypeScript;
             _this.sym = null;
             _this.cloId = -1;
             _this.setText(actualText, hasEscapeSequence);
+            return _this;
         }
         Identifier.prototype.setText = function (actualText, hasEscapeSequence) {
             this.actualText = actualText;
@@ -2669,6 +2673,7 @@ var TypeScript;
         function MissingIdentifier() {
             var _this;
             _this = _super.call(this, "__missing") || this;
+            return _this;
         }
         MissingIdentifier.prototype.isMissing = function () {
             return true;
@@ -2685,6 +2690,7 @@ var TypeScript;
             var _this;
             _this = _super.call(this, NodeType.Label) || this;
             _this.id = id;
+            return _this;
         }
         Label.prototype.printLabel = function () { return this.id.actualText + ":"; };
         Label.prototype.typeCheck = function (typeFlow) {
@@ -2709,6 +2715,7 @@ var TypeScript;
         function Expression(nodeType) {
             var _this;
             _this = _super.call(this, nodeType) || this;
+            return _this;
         }
         Expression.prototype.isExpression = function () { return true; };
         Expression.prototype.isStatementOrExpression = function () { return true; };
@@ -2723,6 +2730,7 @@ var TypeScript;
             _this.operand = operand;
             _this.targetType = null; // Target type for an object literal (null if no target type)
             _this.castTerm = null;
+            return _this;
         }
         UnaryExpression.prototype.addToControlFlow = function (context) {
             _super.prototype.addToControlFlow.call(this, context);
@@ -2869,6 +2877,7 @@ var TypeScript;
             _this.arguments = arguments;
             _this.signature = null;
             _this.minChar = _this.target.minChar;
+            return _this;
         }
         CallExpression.prototype.typeCheck = function (typeFlow) {
             if (this.nodeType == NodeType.New) {
@@ -2900,6 +2909,7 @@ var TypeScript;
             _this = _super.call(this, nodeType) || this;
             _this.operand1 = operand1;
             _this.operand2 = operand2;
+            return _this;
         }
         BinaryExpression.prototype.typeCheck = function (typeFlow) {
             switch (this.nodeType) {
@@ -3054,6 +3064,7 @@ var TypeScript;
             _this.operand1 = operand1;
             _this.operand2 = operand2;
             _this.operand3 = operand3;
+            return _this;
         }
         ConditionalExpression.prototype.typeCheck = function (typeFlow) {
             return typeFlow.typeCheckQMark(this);
@@ -3080,6 +3091,7 @@ var TypeScript;
             _this.value = value;
             _this.hasEmptyFraction = hasEmptyFraction;
             _this.isNegativeZero = false;
+            return _this;
         }
         NumberLiteral.prototype.typeCheck = function (typeFlow) {
             this.type = typeFlow.doubleType;
@@ -3120,6 +3132,7 @@ var TypeScript;
             var _this;
             _this = _super.call(this, NodeType.Regex) || this;
             _this.regex = regex;
+            return _this;
         }
         RegexLiteral.prototype.typeCheck = function (typeFlow) {
             this.type = typeFlow.regexType;
@@ -3141,6 +3154,7 @@ var TypeScript;
             var _this;
             _this = _super.call(this, NodeType.QString) || this;
             _this.text = text;
+            return _this;
         }
         StringLiteral.prototype.emit = function (emitter, tokenId, startLine) {
             emitter.emitParensAndCommentsInPlace(this, true);
@@ -3167,6 +3181,7 @@ var TypeScript;
         function ModuleElement(nodeType) {
             var _this;
             _this = _super.call(this, nodeType) || this;
+            return _this;
         }
         return ModuleElement;
     }(AST));
@@ -3180,6 +3195,7 @@ var TypeScript;
             _this.alias = alias;
             _this.varFlags = VarFlags.None;
             _this.isDynamicImport = false;
+            return _this;
         }
         ImportDeclaration.prototype.isStatementOrExpression = function () { return true; };
         ImportDeclaration.prototype.emit = function (emitter, tokenId, startLine) {
@@ -3242,6 +3258,7 @@ var TypeScript;
             _this.typeExpr = null;
             _this.varFlags = VarFlags.None;
             _this.sym = null;
+            return _this;
         }
         BoundDecl.prototype.isStatementOrExpression = function () { return true; };
         BoundDecl.prototype.isPrivate = function () { return hasFlag(this.varFlags, VarFlags.Private); };
@@ -3261,6 +3278,7 @@ var TypeScript;
         function VarDecl(id, nest) {
             var _this;
             _this = _super.call(this, id, NodeType.VarDecl, nest) || this;
+            return _this;
         }
         VarDecl.prototype.isAmbient = function () { return hasFlag(this.varFlags, VarFlags.Ambient); };
         VarDecl.prototype.isExported = function () { return hasFlag(this.varFlags, VarFlags.Exported); };
@@ -3281,6 +3299,7 @@ var TypeScript;
             _this = _super.call(this, id, NodeType.ArgDecl, 0) || this;
             _this.isOptional = false;
             _this.parameterPropertySym = null;
+            return _this;
         }
         ArgDecl.prototype.isOptionalArg = function () { return this.isOptional || this.init; };
         ArgDecl.prototype.treeViewLabel = function () {
@@ -3331,6 +3350,7 @@ var TypeScript;
             _this.returnStatementsWithExpressions = [];
             _this.scopeType = null; // Type of the FuncDecl, before target typing
             _this.endingToken = null;
+            return _this;
         }
         FuncDecl.prototype.internalName = function () {
             if (this.internalNameCache == null) {
@@ -3458,6 +3478,7 @@ var TypeScript;
             _this.containsUnicodeCharInComment = false;
             _this.vars = vars;
             _this.scopes = scopes;
+            return _this;
         }
         Script.prototype.typeCheck = function (typeFlow) {
             return typeFlow.typeCheckScript(this);
@@ -3517,6 +3538,7 @@ var TypeScript;
             _this.members = members;
             _this.leftCurlyCount = 0;
             _this.rightCurlyCount = 0;
+            return _this;
         }
         return NamedDeclaration;
     }(ModuleElement));
@@ -3535,6 +3557,7 @@ var TypeScript;
             _this.vars = vars;
             _this.scopes = scopes;
             _this.prettyName = _this.name.actualText;
+            return _this;
         }
         ModuleDeclaration.prototype.isExported = function () { return hasFlag(this.modFlags, ModuleFlags.Exported); };
         ModuleDeclaration.prototype.isAmbient = function () { return hasFlag(this.modFlags, ModuleFlags.Ambient); };
@@ -3565,6 +3588,7 @@ var TypeScript;
             _this.extendsList = extendsList;
             _this.implementsList = implementsList;
             _this.varFlags = VarFlags.None;
+            return _this;
         }
         TypeDeclaration.prototype.isExported = function () {
             return hasFlag(this.varFlags, VarFlags.Exported);
@@ -3584,6 +3608,7 @@ var TypeScript;
             _this.constructorDecl = null;
             _this.constructorNestingLevel = 0;
             _this.endingToken = null;
+            return _this;
         }
         ClassDeclaration.prototype.typeCheck = function (typeFlow) {
             return typeFlow.typeCheckClass(this);
@@ -3599,6 +3624,7 @@ var TypeScript;
         function InterfaceDeclaration(name, members, extendsList, implementsList) {
             var _this;
             _this = _super.call(this, NodeType.InterfaceDeclaration, name, extendsList, implementsList, members) || this;
+            return _this;
         }
         InterfaceDeclaration.prototype.typeCheck = function (typeFlow) {
             return typeFlow.typeCheckInterface(this);
@@ -3614,6 +3640,7 @@ var TypeScript;
             var _this;
             _this = _super.call(this, nodeType) || this;
             _this.flags |= ASTFlags.IsStatement;
+            return _this;
         }
         Statement.prototype.isLoop = function () { return false; };
         Statement.prototype.isStatementOrExpression = function () { return true; };
@@ -3632,6 +3659,7 @@ var TypeScript;
             _this = _super.call(this, NodeType.LabeledStatement) || this;
             _this.labels = labels;
             _this.stmt = stmt;
+            return _this;
         }
         LabeledStatement.prototype.emit = function (emitter, tokenId, startLine) {
             emitter.emitParensAndCommentsInPlace(this, true);
@@ -3667,6 +3695,7 @@ var TypeScript;
             _this = _super.call(this, NodeType.Block) || this;
             _this.statements = statements;
             _this.isStatementBlock = isStatementBlock;
+            return _this;
         }
         Block.prototype.emit = function (emitter, tokenId, startLine) {
             emitter.emitParensAndCommentsInPlace(this, true);
@@ -3723,6 +3752,7 @@ var TypeScript;
             _this = _super.call(this, nodeType) || this;
             _this.target = null;
             _this.resolvedTarget = null;
+            return _this;
         }
         Jump.prototype.hasExplicitTarget = function () { return (this.target); };
         Jump.prototype.setResolvedTarget = function (parser, stmt) {
@@ -3775,6 +3805,7 @@ var TypeScript;
             _this = _super.call(this, NodeType.While) || this;
             _this.cond = cond;
             _this.body = null;
+            return _this;
         }
         WhileStatement.prototype.isLoop = function () { return true; };
         WhileStatement.prototype.emit = function (emitter, tokenId, startLine) {
@@ -3829,6 +3860,7 @@ var TypeScript;
             _this.body = null;
             _this.whileAST = null;
             _this.cond = null;
+            return _this;
         }
         DoWhileStatement.prototype.isLoop = function () { return true; };
         DoWhileStatement.prototype.emit = function (emitter, tokenId, startLine) {
@@ -3886,6 +3918,7 @@ var TypeScript;
             _this.cond = cond;
             _this.elseBod = null;
             _this.statement = new ASTSpan();
+            return _this;
         }
         IfStatement.prototype.isCompoundStatement = function () { return true; };
         IfStatement.prototype.emit = function (emitter, tokenId, startLine) {
@@ -3963,6 +3996,7 @@ var TypeScript;
             var _this;
             _this = _super.call(this, NodeType.Return) || this;
             _this.returnExpression = null;
+            return _this;
         }
         ReturnStatement.prototype.emit = function (emitter, tokenId, startLine) {
             emitter.emitParensAndCommentsInPlace(this, true);
@@ -3994,6 +4028,7 @@ var TypeScript;
         function EndCode() {
             var _this;
             _this = _super.call(this, NodeType.EndCode) || this;
+            return _this;
         }
         return EndCode;
     }(AST));
@@ -4009,6 +4044,7 @@ var TypeScript;
             if (_this.lval && (_this.lval.nodeType == NodeType.VarDecl)) {
                 _this.lval.varFlags |= VarFlags.AutoInit;
             }
+            return _this;
         }
         ForInStatement.prototype.isLoop = function () { return true; };
         ForInStatement.prototype.isFiltered = function () {
@@ -4120,6 +4156,7 @@ var TypeScript;
             var _this;
             _this = _super.call(this, NodeType.For) || this;
             _this.init = init;
+            return _this;
         }
         ForStatement.prototype.isLoop = function () { return true; };
         ForStatement.prototype.emit = function (emitter, tokenId, startLine) {
@@ -4213,6 +4250,7 @@ var TypeScript;
             _this = _super.call(this, NodeType.With) || this;
             _this.expr = expr;
             _this.withSym = null;
+            return _this;
         }
         WithStatement.prototype.isCompoundStatement = function () { return true; };
         WithStatement.prototype.emit = function (emitter, tokenId, startLine) {
@@ -4241,6 +4279,7 @@ var TypeScript;
             _this.val = val;
             _this.defaultCase = null;
             _this.statement = new ASTSpan();
+            return _this;
         }
         SwitchStatement.prototype.isCompoundStatement = function () { return true; };
         SwitchStatement.prototype.emit = function (emitter, tokenId, startLine) {
@@ -4312,6 +4351,7 @@ var TypeScript;
             var _this;
             _this = _super.call(this, NodeType.Case) || this;
             _this.expr = null;
+            return _this;
         }
         CaseStatement.prototype.emit = function (emitter, tokenId, startLine) {
             emitter.emitParensAndCommentsInPlace(this, true);
@@ -4367,6 +4407,7 @@ var TypeScript;
             _this = _super.call(this, NodeType.TypeRef) || this;
             _this.term = term;
             _this.arrayCount = arrayCount;
+            return _this;
         }
         TypeReference.prototype.emit = function (emitter, tokenId, startLine) {
             throw new Error("should not emit a type ref");
@@ -4398,6 +4439,7 @@ var TypeScript;
             _this = _super.call(this, NodeType.TryFinally) || this;
             _this.tryNode = tryNode;
             _this.finallyNode = finallyNode;
+            return _this;
         }
         TryFinally.prototype.isCompoundStatement = function () { return true; };
         TryFinally.prototype.emit = function (emitter, tokenId, startLine) {
@@ -4444,6 +4486,7 @@ var TypeScript;
             _this = _super.call(this, NodeType.TryCatch) || this;
             _this.tryNode = tryNode;
             _this.catchNode = catchNode;
+            return _this;
         }
         TryCatch.prototype.isCompoundStatement = function () { return true; };
         TryCatch.prototype.emit = function (emitter, tokenId, startLine) {
@@ -4494,6 +4537,7 @@ var TypeScript;
             var _this;
             _this = _super.call(this, NodeType.Try) || this;
             _this.body = body;
+            return _this;
         }
         Try.prototype.emit = function (emitter, tokenId, startLine) {
             emitter.emitParensAndCommentsInPlace(this, true);
@@ -4529,6 +4573,7 @@ var TypeScript;
             if (_this.param) {
                 _this.param.varFlags |= VarFlags.AutoInit;
             }
+            return _this;
         }
         Catch.prototype.emit = function (emitter, tokenId, startLine) {
             emitter.emitParensAndCommentsInPlace(this, true);
@@ -4597,6 +4642,7 @@ var TypeScript;
             var _this;
             _this = _super.call(this, NodeType.Finally) || this;
             _this.body = body;
+            return _this;
         }
         Finally.prototype.emit = function (emitter, tokenId, startLine) {
             emitter.emitParensAndCommentsInPlace(this, true);
@@ -4629,6 +4675,7 @@ var TypeScript;
             _this.isBlockComment = isBlockComment;
             _this.endsLine = endsLine;
             _this.text = null;
+            return _this;
         }
         Comment.prototype.getText = function () {
             if (this.text == null) {
@@ -4652,6 +4699,7 @@ var TypeScript;
         function DebuggerStatement() {
             var _this;
             _this = _super.call(this, NodeType.Debugger) || this;
+            return _this;
         }
         DebuggerStatement.prototype.emit = function (emitter, tokenId, startLine) {
             emitter.emitParensAndCommentsInPlace(this, true);
diff --git a/tests/baselines/reference/parserharness.js b/tests/baselines/reference/parserharness.js
index f0db6078832..2d219c63e6a 100644
--- a/tests/baselines/reference/parserharness.js
+++ b/tests/baselines/reference/parserharness.js
@@ -2384,6 +2384,7 @@ var Harness;
             _this = _super.call(this, description, block) || this;
             _this.description = description;
             _this.block = block;
+            return _this;
         }
         TestCase.prototype.addChild = function (child) {
             throw new Error("Testcases may not be nested inside other testcases");
@@ -2419,6 +2420,7 @@ var Harness;
             _this = _super.call(this, description, block) || this;
             _this.description = description;
             _this.block = block;
+            return _this;
         }
         /** Run the block, and if the block doesn't raise an error, run the children. */
         Scenario.prototype.run = function (done) {
@@ -2473,6 +2475,7 @@ var Harness;
         function Run() {
             var _this;
             _this = _super.call(this, 'Test Run', null) || this;
+            return _this;
         }
         Run.prototype.run = function () {
             emitLog('start');
diff --git a/tests/baselines/reference/privateInstanceMemberAccessibility.js b/tests/baselines/reference/privateInstanceMemberAccessibility.js
index 618c38b89d5..c07238dff5e 100644
--- a/tests/baselines/reference/privateInstanceMemberAccessibility.js
+++ b/tests/baselines/reference/privateInstanceMemberAccessibility.js
@@ -31,6 +31,7 @@ var Derived = (function (_super) {
         _this = _super.apply(this, arguments) || this;
         _this.x = _super.prototype.foo; // error
         _this.z = _super.prototype.foo; // error
+        return _this;
     }
     Derived.prototype.y = function () {
         return _super.prototype.foo; // error
diff --git a/tests/baselines/reference/privateStaticMemberAccessibility.js b/tests/baselines/reference/privateStaticMemberAccessibility.js
index e953198290b..0d4cfefb63b 100644
--- a/tests/baselines/reference/privateStaticMemberAccessibility.js
+++ b/tests/baselines/reference/privateStaticMemberAccessibility.js
@@ -25,6 +25,7 @@ var Derived = (function (_super) {
         var _this;
         _this = _super.apply(this, arguments) || this;
         _this.bing = function () { return Base.foo; }; // error
+        return _this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/readonlyConstructorAssignment.js b/tests/baselines/reference/readonlyConstructorAssignment.js
index f1b69ecc00b..581b110298a 100644
--- a/tests/baselines/reference/readonlyConstructorAssignment.js
+++ b/tests/baselines/reference/readonlyConstructorAssignment.js
@@ -60,6 +60,7 @@ var B = (function (_super) {
         _this = _super.call(this, x) || this;
         // Fails, x is readonly
         _this.x = 1;
+        return _this;
     }
     return B;
 }(A));
@@ -72,6 +73,7 @@ var C = (function (_super) {
         _this = _super.call(this, x) || this;
         _this.x = x;
         _this.x = 1;
+        return _this;
     }
     return C;
 }(A));
@@ -90,6 +92,7 @@ var E = (function (_super) {
         _this = _super.call(this, x) || this;
         _this.x = x;
         _this.x = 1;
+        return _this;
     }
     return E;
 }(D));
diff --git a/tests/baselines/reference/returnInConstructor1.js b/tests/baselines/reference/returnInConstructor1.js
index cd3a9f4c346..0ee301758cf 100644
--- a/tests/baselines/reference/returnInConstructor1.js
+++ b/tests/baselines/reference/returnInConstructor1.js
@@ -126,6 +126,7 @@ var H = (function (_super) {
         var _this;
         _this = _super.call(this) || this;
         return new G(); //error
+        return _this;
     }
     return H;
 }(F));
@@ -135,6 +136,7 @@ var I = (function (_super) {
         var _this;
         _this = _super.call(this) || this;
         return new G();
+        return _this;
     }
     return I;
 }(G));
diff --git a/tests/baselines/reference/scopeTests.js b/tests/baselines/reference/scopeTests.js
index 3fd9018e945..9436043094e 100644
--- a/tests/baselines/reference/scopeTests.js
+++ b/tests/baselines/reference/scopeTests.js
@@ -30,6 +30,7 @@ var D = (function (_super) {
         _this.v = 1;
         _this.p = 1;
         C.s = 1;
+        return _this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js b/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js
index 29da6d52a38..7fef0a42010 100644
--- a/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js
+++ b/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js
@@ -25,6 +25,7 @@ var Greeter = (function (_super) {
         _this = _super.apply(this, arguments) || this;
         _this.a = 10;
         _this.nameA = "Ten";
+        return _this;
     }
     return Greeter;
 }(AbstractGreeter));
diff --git a/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js.map b/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js.map
index 3a75f3d3b66..14f7f65f050 100644
--- a/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js.map
+++ b/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js.map
@@ -1,2 +1,2 @@
 //// [sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js.map]
-{"version":3,"file":"sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js","sourceRoot":"","sources":["sourceMapValidationClassWithDefaultConstructorAndExtendsClause.ts"],"names":[],"mappings":";;;;;AAAA;IAAA;IACA,CAAC;IAAD,sBAAC;AAAD,CAAC,AADD,IACC;AAED;IAAsB,2BAAe;IAArC;QAAA,UAGC;;QAFU,OAAC,GAAG,EAAE,CAAC;QACP,WAAK,GAAG,KAAK,CAAC;IACzB,CAAC;IAAD,cAAC;AAAD,CAAC,AAHD,CAAsB,eAAe,GAGpC"}
\ No newline at end of file
+{"version":3,"file":"sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js","sourceRoot":"","sources":["sourceMapValidationClassWithDefaultConstructorAndExtendsClause.ts"],"names":[],"mappings":";;;;;AAAA;IAAA;IACA,CAAC;IAAD,sBAAC;AAAD,CAAC,AADD,IACC;AAED;IAAsB,2BAAe;IAArC;QAAA,UAGC;;QAFU,OAAC,GAAG,EAAE,CAAC;QACP,WAAK,GAAG,KAAK,CAAC;;IACzB,CAAC;IAAD,cAAC;AAAD,CAAC,AAHD,CAAsB,eAAe,GAGpC"}
\ No newline at end of file
diff --git a/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.sourcemap.txt b/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.sourcemap.txt
index 7c05c1b4d84..e1adf2f7a29 100644
--- a/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.sourcemap.txt
+++ b/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.sourcemap.txt
@@ -130,6 +130,7 @@ sourceFile:sourceMapValidationClassWithDefaultConstructorAndExtendsClause.ts
 4 >Emitted(17, 28) Source(6, 25) + SourceIndex(0)
 5 >Emitted(17, 29) Source(6, 26) + SourceIndex(0)
 ---
+>>>        return _this;
 >>>    }
 1 >^^^^
 2 >    ^
@@ -137,8 +138,8 @@ sourceFile:sourceMapValidationClassWithDefaultConstructorAndExtendsClause.ts
 1 >
   >
 2 >    }
-1 >Emitted(18, 5) Source(7, 1) + SourceIndex(0)
-2 >Emitted(18, 6) Source(7, 2) + SourceIndex(0)
+1 >Emitted(19, 5) Source(7, 1) + SourceIndex(0)
+2 >Emitted(19, 6) Source(7, 2) + SourceIndex(0)
 ---
 >>>    return Greeter;
 1->^^^^
@@ -146,8 +147,8 @@ sourceFile:sourceMapValidationClassWithDefaultConstructorAndExtendsClause.ts
 3 >                  ^^^->
 1->
 2 >    }
-1->Emitted(19, 5) Source(7, 1) + SourceIndex(0)
-2 >Emitted(19, 19) Source(7, 2) + SourceIndex(0)
+1->Emitted(20, 5) Source(7, 1) + SourceIndex(0)
+2 >Emitted(20, 19) Source(7, 2) + SourceIndex(0)
 ---
 >>>}(AbstractGreeter));
 1->
@@ -166,11 +167,11 @@ sourceFile:sourceMapValidationClassWithDefaultConstructorAndExtendsClause.ts
   >                     public a = 10;
   >                     public nameA = "Ten";
   >                 }
-1->Emitted(20, 1) Source(7, 1) + SourceIndex(0)
-2 >Emitted(20, 2) Source(7, 2) + SourceIndex(0)
-3 >Emitted(20, 2) Source(4, 1) + SourceIndex(0)
-4 >Emitted(20, 3) Source(4, 23) + SourceIndex(0)
-5 >Emitted(20, 18) Source(4, 38) + SourceIndex(0)
-6 >Emitted(20, 21) Source(7, 2) + SourceIndex(0)
+1->Emitted(21, 1) Source(7, 1) + SourceIndex(0)
+2 >Emitted(21, 2) Source(7, 2) + SourceIndex(0)
+3 >Emitted(21, 2) Source(4, 1) + SourceIndex(0)
+4 >Emitted(21, 3) Source(4, 23) + SourceIndex(0)
+5 >Emitted(21, 18) Source(4, 38) + SourceIndex(0)
+6 >Emitted(21, 21) Source(7, 2) + SourceIndex(0)
 ---
 >>>//# sourceMappingURL=sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js.map
\ No newline at end of file
diff --git a/tests/baselines/reference/staticInheritance.js b/tests/baselines/reference/staticInheritance.js
index 462f2382f3c..5e769cab563 100644
--- a/tests/baselines/reference/staticInheritance.js
+++ b/tests/baselines/reference/staticInheritance.js
@@ -31,6 +31,7 @@ var B = (function (_super) {
         _this = _super.apply(this, arguments) || this;
         _this.p1 = doThing(A); // OK
         _this.p2 = doThing(B); // OK
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/staticPropSuper.js b/tests/baselines/reference/staticPropSuper.js
index f5bac0135af..6240f8c454f 100644
--- a/tests/baselines/reference/staticPropSuper.js
+++ b/tests/baselines/reference/staticPropSuper.js
@@ -52,6 +52,7 @@ var B = (function (_super) {
         var _this;
         var x = 1; // should not error
         _this = _super.call(this) || this;
+        return _this;
     }
     return B;
 }(A));
@@ -62,6 +63,7 @@ var C = (function (_super) {
         var _this;
         _this.p = 10;
         var x = 1; // should error
+        return _this;
     }
     return C;
 }(A));
@@ -71,6 +73,7 @@ var D = (function (_super) {
         var _this;
         _this.p = 11;
         var x = 1; // should error
+        return _this;
     }
     return D;
 }(A));
@@ -80,6 +83,7 @@ var E = (function (_super) {
         var _this;
         _this.p = 12;
         var x = 1; // should error
+        return _this;
     }
     return E;
 }(A));
diff --git a/tests/baselines/reference/strictModeInConstructor.js b/tests/baselines/reference/strictModeInConstructor.js
index 1af13b1ce7a..4e1c483f1c1 100644
--- a/tests/baselines/reference/strictModeInConstructor.js
+++ b/tests/baselines/reference/strictModeInConstructor.js
@@ -78,6 +78,7 @@ var B = (function (_super) {
         "use strict"; // No error
         _this = _super.call(this) || this;
         _this.s = 9;
+        return _this;
     }
     return B;
 }(A));
@@ -88,6 +89,7 @@ var C = (function (_super) {
         _this = _super.call(this) || this; // No error
         _this.s = 9;
         "use strict";
+        return _this;
     }
     return C;
 }(A));
@@ -99,6 +101,7 @@ var D = (function (_super) {
         var x = 1; // Error
         _this = _super.call(this) || this;
         "use strict";
+        return _this;
     }
     return D;
 }(A));
@@ -108,6 +111,7 @@ var Bs = (function (_super) {
         var _this;
         "use strict"; // No error
         _this = _super.call(this) || this;
+        return _this;
     }
     return Bs;
 }(A));
@@ -118,6 +122,7 @@ var Cs = (function (_super) {
         var _this;
         _this = _super.call(this) || this; // No error
         "use strict";
+        return _this;
     }
     return Cs;
 }(A));
@@ -129,6 +134,7 @@ var Ds = (function (_super) {
         var x = 1; // no Error
         _this = _super.call(this) || this;
         "use strict";
+        return _this;
     }
     return Ds;
 }(A));
diff --git a/tests/baselines/reference/superAccess2.js b/tests/baselines/reference/superAccess2.js
index 807347e1d16..408f9051bad 100644
--- a/tests/baselines/reference/superAccess2.js
+++ b/tests/baselines/reference/superAccess2.js
@@ -48,6 +48,7 @@ var Q = (function (_super) {
         _this = _super.call(this) || this;
         _this.z = z;
         _this.xx = _super.prototype.;
+        return _this;
     }
     Q.prototype.foo = function (zz) {
         if (zz === void 0) { zz = _super.prototype.; }
diff --git a/tests/baselines/reference/superCallArgsMustMatch.js b/tests/baselines/reference/superCallArgsMustMatch.js
index 770cb0bf79f..dc450147f88 100644
--- a/tests/baselines/reference/superCallArgsMustMatch.js
+++ b/tests/baselines/reference/superCallArgsMustMatch.js
@@ -45,6 +45,7 @@ var T6 = (function (_super) {
         // which is instantiated with 'number' in the extends clause
         _this = _super.call(this, "hi") || this;
         var x = _this.foo;
+        return _this;
     }
     return T6;
 }(T5));
diff --git a/tests/baselines/reference/superCallAssignResult.js b/tests/baselines/reference/superCallAssignResult.js
index 4eeabdfa282..6e30cc64052 100644
--- a/tests/baselines/reference/superCallAssignResult.js
+++ b/tests/baselines/reference/superCallAssignResult.js
@@ -27,6 +27,7 @@ var H = (function (_super) {
         var _this;
         var x = _this = _super.call(this, 5) || this; // Should be of type void, not E.
         x = 5;
+        return _this;
     }
     return H;
 }(E));
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing1.js b/tests/baselines/reference/superCallBeforeThisAccessing1.js
index 6af4482f371..a5d6ec18ce3 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing1.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing1.js
@@ -36,6 +36,7 @@ var D = (function (_super) {
             t: _this._t
         };
         var i = Factory.create(s);
+        return _this;
     }
     return D;
 }(Base));
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing2.js b/tests/baselines/reference/superCallBeforeThisAccessing2.js
index 8ab6c5f349c..c7a206dbbbe 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing2.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing2.js
@@ -26,6 +26,7 @@ var D = (function (_super) {
     function D() {
         var _this;
         _this = _super.call(this, function () { _this._t; }) || this; // no error. only check when this is directly accessing in constructor
+        return _this;
     }
     return D;
 }(Base));
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing3.js b/tests/baselines/reference/superCallBeforeThisAccessing3.js
index f77cb964179..185767fefb6 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing3.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing3.js
@@ -32,6 +32,7 @@ var D = (function (_super) {
         x(); // no error; we only check super is called before this when the container is a constructor
         _this._t; // error
         _this = _super.call(this, undefined) || this;
+        return _this;
     }
     return D;
 }(Base));
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing4.js b/tests/baselines/reference/superCallBeforeThisAccessing4.js
index c147b0d84cc..311b7ca2183 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing4.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing4.js
@@ -27,6 +27,7 @@ var D = (function (_super) {
         var _this;
         _this._t;
         _this = _super.call(this) || this;
+        return _this;
     }
     return D;
 }(null));
@@ -36,6 +37,7 @@ var E = (function (_super) {
         var _this;
         _this = _super.call(this) || this;
         _this._t;
+        return _this;
     }
     return E;
 }(null));
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing5.js b/tests/baselines/reference/superCallBeforeThisAccessing5.js
index 8fff8068ec0..57228538faf 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing5.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing5.js
@@ -18,6 +18,7 @@ var D = (function (_super) {
     function D() {
         var _this;
         _this._t; // No error
+        return _this;
     }
     return D;
 }(null));
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing6.js b/tests/baselines/reference/superCallBeforeThisAccessing6.js
index 843a1d3b2cf..e630d539f14 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing6.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing6.js
@@ -26,6 +26,7 @@ var D = (function (_super) {
     function D() {
         var _this;
         _this = _super.call(this, _this) || this;
+        return _this;
     }
     return D;
 }(Base));
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing7.js b/tests/baselines/reference/superCallBeforeThisAccessing7.js
index d6ad948a08c..9cfe8736774 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing7.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing7.js
@@ -32,6 +32,7 @@ var D = (function (_super) {
             j: _this._t
         };
         _this = _super.call(this, undefined) || this;
+        return _this;
     }
     return D;
 }(Base));
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing8.js b/tests/baselines/reference/superCallBeforeThisAccessing8.js
index cbf0236c4cc..fe459b5e031 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing8.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing8.js
@@ -32,6 +32,7 @@ var D = (function (_super) {
             k: _this = _super.call(this, undefined) || this,
             j: _this._t
         };
+        return _this;
     }
     return D;
 }(Base));
diff --git a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType1.js b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType1.js
index 6de41cb5188..2cfc0bfcbd4 100644
--- a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType1.js
+++ b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType1.js
@@ -22,6 +22,7 @@ var D = (function (_super) {
     function D() {
         var _this;
         _this = _super.call(this) || this;
+        return _this;
     }
     return D;
 }(B));
diff --git a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType2.js b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType2.js
index 5ae8f8b3874..f9eeadc98e6 100644
--- a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType2.js
+++ b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType2.js
@@ -21,6 +21,7 @@ var D = (function (_super) {
     function D() {
         var _this;
         _this = _super.call(this) || this;
+        return _this;
     }
     return D;
 }(B));
diff --git a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithIncorrectNumberOfTypeArguments1.js b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithIncorrectNumberOfTypeArguments1.js
index bc85d74c4c8..02bec67d7aa 100644
--- a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithIncorrectNumberOfTypeArguments1.js
+++ b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithIncorrectNumberOfTypeArguments1.js
@@ -27,6 +27,7 @@ var B = (function (_super) {
     function B() {
         var _this;
         _this = _super.call(this, function (value) { return String(value); }) || this;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithNoTypeArguments1.js b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithNoTypeArguments1.js
index a1736bb45f0..55c6ee6f445 100644
--- a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithNoTypeArguments1.js
+++ b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithNoTypeArguments1.js
@@ -27,6 +27,7 @@ var B = (function (_super) {
     function B() {
         var _this;
         _this = _super.call(this, function (value) { return String(value); }) || this;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/superCallFromClassThatDerivesNonGenericTypeButWithTypeArguments1.js b/tests/baselines/reference/superCallFromClassThatDerivesNonGenericTypeButWithTypeArguments1.js
index c5beb5df5b5..977377e41d4 100644
--- a/tests/baselines/reference/superCallFromClassThatDerivesNonGenericTypeButWithTypeArguments1.js
+++ b/tests/baselines/reference/superCallFromClassThatDerivesNonGenericTypeButWithTypeArguments1.js
@@ -27,6 +27,7 @@ var B = (function (_super) {
     function B() {
         var _this;
         _this = _super.call(this, function (value) { return String(value); }) || this;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/superCallInNonStaticMethod.js b/tests/baselines/reference/superCallInNonStaticMethod.js
index 1dd120eeb5c..503aee2dcc6 100644
--- a/tests/baselines/reference/superCallInNonStaticMethod.js
+++ b/tests/baselines/reference/superCallInNonStaticMethod.js
@@ -71,6 +71,7 @@ var Other = (function (_super) {
         _this.propertyInitializer = _super.prototype.instanceMethod.call(_this);
         _this.functionProperty = function () { _super.prototype.instanceMethod.call(_this); };
         _super.prototype.instanceMethod.call(_this);
+        return _this;
     }
     // in instance method
     Other.prototype.instanceMethod = function () {
diff --git a/tests/baselines/reference/superCallInsideClassDeclaration.js b/tests/baselines/reference/superCallInsideClassDeclaration.js
index f47b50d4915..326662abdac 100644
--- a/tests/baselines/reference/superCallInsideClassDeclaration.js
+++ b/tests/baselines/reference/superCallInsideClassDeclaration.js
@@ -41,9 +41,11 @@ var B = (function (_super) {
             function D() {
                 var _this;
                 _this = _super.call(this) || this;
+                return _this;
             }
             return D;
         }(C));
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/superCallInsideClassExpression.js b/tests/baselines/reference/superCallInsideClassExpression.js
index b9e1f6c9786..5797085726d 100644
--- a/tests/baselines/reference/superCallInsideClassExpression.js
+++ b/tests/baselines/reference/superCallInsideClassExpression.js
@@ -41,9 +41,11 @@ var B = (function (_super) {
             function class_1() {
                 var _this;
                 _this = _super.call(this) || this;
+                return _this;
             }
             return class_1;
         }(C));
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/superCallInsideObjectLiteralExpression.js b/tests/baselines/reference/superCallInsideObjectLiteralExpression.js
index 68a9c19e819..636b03c227f 100644
--- a/tests/baselines/reference/superCallInsideObjectLiteralExpression.js
+++ b/tests/baselines/reference/superCallInsideObjectLiteralExpression.js
@@ -32,6 +32,7 @@ var B = (function (_super) {
         var x = {
             x: _this = _super.call(this) || this
         };
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/superCallOutsideConstructor.js b/tests/baselines/reference/superCallOutsideConstructor.js
index 774dde72340..65a8b435166 100644
--- a/tests/baselines/reference/superCallOutsideConstructor.js
+++ b/tests/baselines/reference/superCallOutsideConstructor.js
@@ -46,6 +46,7 @@ var D = (function (_super) {
         var y2 = function () {
             _this = _super.call(this) || this;
         };
+        return _this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/superCallParameterContextualTyping1.js b/tests/baselines/reference/superCallParameterContextualTyping1.js
index a311ce95fc7..4e4ae47967a 100644
--- a/tests/baselines/reference/superCallParameterContextualTyping1.js
+++ b/tests/baselines/reference/superCallParameterContextualTyping1.js
@@ -30,6 +30,7 @@ var B = (function (_super) {
     function B() {
         var _this;
         _this = _super.call(this, function (value) { return String(value.toExponential()); }) || this;
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/superCallParameterContextualTyping2.js b/tests/baselines/reference/superCallParameterContextualTyping2.js
index 9439871f38c..f3a246c6389 100644
--- a/tests/baselines/reference/superCallParameterContextualTyping2.js
+++ b/tests/baselines/reference/superCallParameterContextualTyping2.js
@@ -29,6 +29,7 @@ var C = (function (_super) {
     function C() {
         var _this;
         _this = _super.call(this, function (value) { return String(value()); }) || this;
+        return _this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/superCallParameterContextualTyping3.js b/tests/baselines/reference/superCallParameterContextualTyping3.js
index d77df52ddd6..e7b8b355108 100644
--- a/tests/baselines/reference/superCallParameterContextualTyping3.js
+++ b/tests/baselines/reference/superCallParameterContextualTyping3.js
@@ -62,6 +62,7 @@ var C = (function (_super) {
                 p.length;
             }
         });
+        return _this;
     }
     return C;
 }(CBase));
diff --git a/tests/baselines/reference/superCalls.js b/tests/baselines/reference/superCalls.js
index 33127da6437..2fe7712ce68 100644
--- a/tests/baselines/reference/superCalls.js
+++ b/tests/baselines/reference/superCalls.js
@@ -53,6 +53,7 @@ var Derived = (function (_super) {
         //type of super call expression is void
         var p = _this = _super.call(this, '') || this;
         var p = v();
+        return _this;
     }
     return Derived;
 }(Base));
@@ -67,6 +68,7 @@ var OtherDerived = (function (_super) {
         var _this;
         var p = '';
         _this = _super.call(this) || this;
+        return _this;
     }
     return OtherDerived;
 }(OtherBase));
diff --git a/tests/baselines/reference/superCallsInConstructor.js b/tests/baselines/reference/superCallsInConstructor.js
index be34657a0c1..48b79acadf4 100644
--- a/tests/baselines/reference/superCallsInConstructor.js
+++ b/tests/baselines/reference/superCallsInConstructor.js
@@ -51,6 +51,7 @@ var Derived = (function (_super) {
         catch (e) {
             _this = _super.call(this) || this;
         }
+        return _this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/superErrors.js b/tests/baselines/reference/superErrors.js
index 2e68370fc32..93676c5d8f3 100644
--- a/tests/baselines/reference/superErrors.js
+++ b/tests/baselines/reference/superErrors.js
@@ -93,6 +93,7 @@ var RegisteredUser = (function (_super) {
             var _this = this;
             return function () { return _super.; };
         })();
+        return _this;
     }
     RegisteredUser.prototype.sayHello = function () {
         // super call in a method
diff --git a/tests/baselines/reference/superInConstructorParam1.js b/tests/baselines/reference/superInConstructorParam1.js
index 56e40b65e10..7519a8253ec 100644
--- a/tests/baselines/reference/superInConstructorParam1.js
+++ b/tests/baselines/reference/superInConstructorParam1.js
@@ -29,6 +29,7 @@ var C = (function (_super) {
     function C(a) {
         var _this;
         if (a === void 0) { a = _super.foo.call(_this); }
+        return _this;
     }
     return C;
 }(B));
diff --git a/tests/baselines/reference/superInLambdas.js b/tests/baselines/reference/superInLambdas.js
index 5a1f48f3826..9b4d956dc5a 100644
--- a/tests/baselines/reference/superInLambdas.js
+++ b/tests/baselines/reference/superInLambdas.js
@@ -92,6 +92,7 @@ var RegisteredUser = (function (_super) {
         _super.prototype.sayHello.call(_this);
         // super call in a lambda in a constructor 
         var x = function () { return _super.prototype.sayHello.call(_this); };
+        return _this;
     }
     RegisteredUser.prototype.sayHello = function () {
         var _this = this;
@@ -110,6 +111,7 @@ var RegisteredUser2 = (function (_super) {
         _this.name = "Joe";
         // super call in a nested lambda in a constructor 
         var x = function () { return function () { return function () { return _super.prototype.sayHello.call(_this); }; }; };
+        return _this;
     }
     RegisteredUser2.prototype.sayHello = function () {
         var _this = this;
@@ -126,6 +128,7 @@ var RegisteredUser3 = (function (_super) {
         _this.name = "Sam";
         // super property in a nested lambda in a constructor 
         var superName = function () { return function () { return function () { return _super.prototype.name; }; }; };
+        return _this;
     }
     RegisteredUser3.prototype.sayHello = function () {
         var _this = this;
@@ -142,6 +145,7 @@ var RegisteredUser4 = (function (_super) {
         _this.name = "Mark";
         // super in a nested lambda in a constructor 
         var x = function () { return function () { return _super.prototype.; }; };
+        return _this;
     }
     RegisteredUser4.prototype.sayHello = function () {
         var _this = this;
diff --git a/tests/baselines/reference/superNewCall1.js b/tests/baselines/reference/superNewCall1.js
index 32c4da4d4e4..30b07308bb2 100644
--- a/tests/baselines/reference/superNewCall1.js
+++ b/tests/baselines/reference/superNewCall1.js
@@ -29,6 +29,7 @@ var B = (function (_super) {
     function B() {
         var _this;
         new _super.prototype(function (value) { return String(value); });
+        return _this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/superPropertyAccess1.js b/tests/baselines/reference/superPropertyAccess1.js
index c9865806570..b6559a63a98 100644
--- a/tests/baselines/reference/superPropertyAccess1.js
+++ b/tests/baselines/reference/superPropertyAccess1.js
@@ -54,6 +54,7 @@ var D = (function (_super) {
         _this = _super.call(this) || this;
         _super.prototype.bar.call(_this);
         _super.prototype.x; // error
+        return _this;
     }
     D.prototype.foo = function () {
         _super.prototype.bar.call(this);
diff --git a/tests/baselines/reference/superPropertyAccess2.js b/tests/baselines/reference/superPropertyAccess2.js
index df6e08177cb..eded4e74a7f 100644
--- a/tests/baselines/reference/superPropertyAccess2.js
+++ b/tests/baselines/reference/superPropertyAccess2.js
@@ -54,6 +54,7 @@ var D = (function (_super) {
         _this = _super.call(this) || this;
         _super.prototype.bar.call(_this); // error
         _super.prototype.x; // error
+        return _this;
     }
     D.foo = function () {
         _super.bar.call(this); // OK
diff --git a/tests/baselines/reference/superPropertyAccessNoError.js b/tests/baselines/reference/superPropertyAccessNoError.js
index d8dda26288c..2ba460d18f7 100644
--- a/tests/baselines/reference/superPropertyAccessNoError.js
+++ b/tests/baselines/reference/superPropertyAccessNoError.js
@@ -103,6 +103,7 @@ var SomeDerivedClass = (function (_super) {
         _this = _super.call(this) || this;
         var x = _super.prototype.func.call(_this);
         var x;
+        return _this;
     }
     SomeDerivedClass.prototype.fn = function () {
         var _this = this;
diff --git a/tests/baselines/reference/superPropertyAccess_ES5.js b/tests/baselines/reference/superPropertyAccess_ES5.js
index 1d2ab4c2a3f..011c5129e9f 100644
--- a/tests/baselines/reference/superPropertyAccess_ES5.js
+++ b/tests/baselines/reference/superPropertyAccess_ES5.js
@@ -53,6 +53,7 @@ var MyDerived = (function (_super) {
         _this = _super.call(this) || this;
         var f1 = _super.prototype.getValue.call(_this);
         var f2 = _super.prototype.value;
+        return _this;
     }
     return MyDerived;
 }(MyBase));
diff --git a/tests/baselines/reference/superWithGenericSpecialization.js b/tests/baselines/reference/superWithGenericSpecialization.js
index 499c0a6de1f..1152399e6eb 100644
--- a/tests/baselines/reference/superWithGenericSpecialization.js
+++ b/tests/baselines/reference/superWithGenericSpecialization.js
@@ -30,6 +30,7 @@ var D = (function (_super) {
     function D() {
         var _this;
         _this = _super.call(this) || this; // uses the type parameter type of the base class, ie string
+        return _this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/superWithGenerics.js b/tests/baselines/reference/superWithGenerics.js
index 471c7cd36ac..f2580d30c5f 100644
--- a/tests/baselines/reference/superWithGenerics.js
+++ b/tests/baselines/reference/superWithGenerics.js
@@ -22,6 +22,7 @@ var D = (function (_super) {
     function D() {
         var _this;
         _this = _super.call(this) || this;
+        return _this;
     }
     return D;
 }(B));
diff --git a/tests/baselines/reference/superWithTypeArgument.js b/tests/baselines/reference/superWithTypeArgument.js
index cc46fa96896..a1c04975404 100644
--- a/tests/baselines/reference/superWithTypeArgument.js
+++ b/tests/baselines/reference/superWithTypeArgument.js
@@ -25,6 +25,7 @@ var D = (function (_super) {
     function D() {
         var _this;
         _super.prototype..call(_this);
+        return _this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/superWithTypeArgument2.js b/tests/baselines/reference/superWithTypeArgument2.js
index 4b5176bed96..42a0e46d4c0 100644
--- a/tests/baselines/reference/superWithTypeArgument2.js
+++ b/tests/baselines/reference/superWithTypeArgument2.js
@@ -25,6 +25,7 @@ var D = (function (_super) {
     function D(x) {
         var _this;
         _super.prototype..call(_this, x);
+        return _this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/superWithTypeArgument3.js b/tests/baselines/reference/superWithTypeArgument3.js
index aa70803de4d..803e5c264c2 100644
--- a/tests/baselines/reference/superWithTypeArgument3.js
+++ b/tests/baselines/reference/superWithTypeArgument3.js
@@ -30,6 +30,7 @@ var D = (function (_super) {
     function D() {
         var _this;
         _super.prototype..call(_this);
+        return _this;
     }
     D.prototype.bar = function () {
         _super.prototype.bar.call(this, null);
diff --git a/tests/baselines/reference/targetTypeBaseCalls.js b/tests/baselines/reference/targetTypeBaseCalls.js
index a9bbc34123f..a08380b173f 100644
--- a/tests/baselines/reference/targetTypeBaseCalls.js
+++ b/tests/baselines/reference/targetTypeBaseCalls.js
@@ -37,6 +37,7 @@ var Bar = (function (_super) {
     function Bar() {
         var _this;
         _this = _super.call(this, function (s) { s = 5; }) || this;
+        return _this;
     }
     return Bar;
 }(Foo)); // error, if types are applied correctly
diff --git a/tests/baselines/reference/thisInInvalidContexts.js b/tests/baselines/reference/thisInInvalidContexts.js
index 218ebfb1686..10629d579ba 100644
--- a/tests/baselines/reference/thisInInvalidContexts.js
+++ b/tests/baselines/reference/thisInInvalidContexts.js
@@ -72,6 +72,7 @@ var ClassWithNoInitializer = (function (_super) {
     function ClassWithNoInitializer() {
         var _this;
         _this = _super.call(this, _this) || this; // Error
+        return _this;
     }
     return ClassWithNoInitializer;
 }(BaseErrClass));
@@ -82,6 +83,7 @@ var ClassWithInitializer = (function (_super) {
         var _this;
         _this = _super.call(this, _this) || this; // Error
         _this.t = 4;
+        return _this;
     }
     return ClassWithInitializer;
 }(BaseErrClass));
diff --git a/tests/baselines/reference/thisInInvalidContextsExternalModule.js b/tests/baselines/reference/thisInInvalidContextsExternalModule.js
index c14f71ac0b6..444952fea3f 100644
--- a/tests/baselines/reference/thisInInvalidContextsExternalModule.js
+++ b/tests/baselines/reference/thisInInvalidContextsExternalModule.js
@@ -73,6 +73,7 @@ var ClassWithNoInitializer = (function (_super) {
     function ClassWithNoInitializer() {
         var _this;
         _this = _super.call(this, _this) || this; // error: "super" has to be called before "this" accessing
+        return _this;
     }
     return ClassWithNoInitializer;
 }(BaseErrClass));
@@ -83,6 +84,7 @@ var ClassWithInitializer = (function (_super) {
         var _this;
         _this = _super.call(this, _this) || this; // Error
         _this.t = 4;
+        return _this;
     }
     return ClassWithInitializer;
 }(BaseErrClass));
diff --git a/tests/baselines/reference/thisInSuperCall.js b/tests/baselines/reference/thisInSuperCall.js
index cf64eebced1..f9d9f8694c9 100644
--- a/tests/baselines/reference/thisInSuperCall.js
+++ b/tests/baselines/reference/thisInSuperCall.js
@@ -38,6 +38,7 @@ var Foo = (function (_super) {
     function Foo() {
         var _this;
         _this = _super.call(this, _this) || this; // error: "super" has to be called before "this" accessing
+        return _this;
     }
     return Foo;
 }(Base));
@@ -47,6 +48,7 @@ var Foo2 = (function (_super) {
         var _this;
         _this = _super.call(this, _this) || this; // error
         _this.p = 0;
+        return _this;
     }
     return Foo2;
 }(Base));
@@ -56,6 +58,7 @@ var Foo3 = (function (_super) {
         var _this;
         _this = _super.call(this, _this) || this; // error
         _this.p = p;
+        return _this;
     }
     return Foo3;
 }(Base));
diff --git a/tests/baselines/reference/thisInSuperCall1.js b/tests/baselines/reference/thisInSuperCall1.js
index eba933d9893..3185e42dab6 100644
--- a/tests/baselines/reference/thisInSuperCall1.js
+++ b/tests/baselines/reference/thisInSuperCall1.js
@@ -27,6 +27,7 @@ var Foo = (function (_super) {
         var _this;
         _this = _super.call(this, _this) || this;
         _this.x = x;
+        return _this;
     }
     return Foo;
 }(Base));
diff --git a/tests/baselines/reference/thisInSuperCall2.js b/tests/baselines/reference/thisInSuperCall2.js
index ed6baabb408..b9f7571868a 100644
--- a/tests/baselines/reference/thisInSuperCall2.js
+++ b/tests/baselines/reference/thisInSuperCall2.js
@@ -35,6 +35,7 @@ var Foo = (function (_super) {
     function Foo() {
         var _this;
         _this = _super.call(this, _this) || this; // error: "super" has to be called before "this" accessing
+        return _this;
     }
     return Foo;
 }(Base));
@@ -44,6 +45,7 @@ var Foo2 = (function (_super) {
         var _this;
         _this = _super.call(this, _this) || this; // error
         _this.x = 0;
+        return _this;
     }
     return Foo2;
 }(Base));
diff --git a/tests/baselines/reference/thisInSuperCall3.js b/tests/baselines/reference/thisInSuperCall3.js
index d705d5fa7e0..309ebf93407 100644
--- a/tests/baselines/reference/thisInSuperCall3.js
+++ b/tests/baselines/reference/thisInSuperCall3.js
@@ -29,6 +29,7 @@ var Foo = (function (_super) {
         var _this;
         _this = _super.call(this, _this) || this;
         _this.x = 0;
+        return _this;
     }
     return Foo;
 }(Base));
diff --git a/tests/baselines/reference/tsxDynamicTagName5.js b/tests/baselines/reference/tsxDynamicTagName5.js
index 76b79dbc7dc..307cd0fca93 100644
--- a/tests/baselines/reference/tsxDynamicTagName5.js
+++ b/tests/baselines/reference/tsxDynamicTagName5.js
@@ -33,6 +33,7 @@ var Text = (function (_super) {
         var _this;
         _this = _super.apply(this, arguments) || this;
         _this._tagName = 'div';
+        return _this;
     }
     Text.prototype.render = function () {
         return (<this._tagName />);
diff --git a/tests/baselines/reference/tsxDynamicTagName7.js b/tests/baselines/reference/tsxDynamicTagName7.js
index c55ceb100ea..39e30b6ba38 100644
--- a/tests/baselines/reference/tsxDynamicTagName7.js
+++ b/tests/baselines/reference/tsxDynamicTagName7.js
@@ -33,6 +33,7 @@ var Text = (function (_super) {
         var _this;
         _this = _super.apply(this, arguments) || this;
         _this._tagName = 'div';
+        return _this;
     }
     Text.prototype.render = function () {
         return (<this /> // this should be an error
diff --git a/tests/baselines/reference/tsxDynamicTagName8.js b/tests/baselines/reference/tsxDynamicTagName8.js
index 57ce2becbad..77423709347 100644
--- a/tests/baselines/reference/tsxDynamicTagName8.js
+++ b/tests/baselines/reference/tsxDynamicTagName8.js
@@ -33,6 +33,7 @@ var Text = (function (_super) {
         var _this;
         _this = _super.apply(this, arguments) || this;
         _this._tagName = 'div';
+        return _this;
     }
     Text.prototype.render = function () {
         return (<this._tagName> Hello world </this._tagName>);
diff --git a/tests/baselines/reference/tsxDynamicTagName9.js b/tests/baselines/reference/tsxDynamicTagName9.js
index 1bc14eb32ee..6b5d130c0b4 100644
--- a/tests/baselines/reference/tsxDynamicTagName9.js
+++ b/tests/baselines/reference/tsxDynamicTagName9.js
@@ -33,6 +33,7 @@ var Text = (function (_super) {
         var _this;
         _this = _super.apply(this, arguments) || this;
         _this._tagName = 'div';
+        return _this;
     }
     Text.prototype.render = function () {
         return (<this._tagName> Hello world </this._tagName>);
diff --git a/tests/baselines/reference/typeGuardOfFormThisMember.js b/tests/baselines/reference/typeGuardOfFormThisMember.js
index fefb1e7ff38..3995ffd447c 100644
--- a/tests/baselines/reference/typeGuardOfFormThisMember.js
+++ b/tests/baselines/reference/typeGuardOfFormThisMember.js
@@ -121,6 +121,7 @@ var Test;
             var _this;
             _this = _super.call(this, path) || this;
             _this.content = content;
+            return _this;
         }
         return File;
     }(FileSystemObject));
diff --git a/tests/baselines/reference/typeGuardOfFormThisMemberErrors.js b/tests/baselines/reference/typeGuardOfFormThisMemberErrors.js
index ed53a308808..14807ddd88c 100644
--- a/tests/baselines/reference/typeGuardOfFormThisMemberErrors.js
+++ b/tests/baselines/reference/typeGuardOfFormThisMemberErrors.js
@@ -71,6 +71,7 @@ var Test;
             var _this;
             _this = _super.call(this, path) || this;
             _this.content = content;
+            return _this;
         }
         return File;
     }(FileSystemObject));
diff --git a/tests/baselines/reference/typeOfSuperCall.js b/tests/baselines/reference/typeOfSuperCall.js
index 70ace4becb4..179e981b8d1 100644
--- a/tests/baselines/reference/typeOfSuperCall.js
+++ b/tests/baselines/reference/typeOfSuperCall.js
@@ -24,6 +24,7 @@ var D = (function (_super) {
     function D() {
         var _this;
         var x = _this = _super.call(this) || this;
+        return _this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/typeRelationships.js b/tests/baselines/reference/typeRelationships.js
index 87f0f60c53f..eee99568638 100644
--- a/tests/baselines/reference/typeRelationships.js
+++ b/tests/baselines/reference/typeRelationships.js
@@ -78,6 +78,7 @@ var D = (function (_super) {
         _this.self2 = _this.self;
         _this.self3 = _this.foo();
         _this.d = new D();
+        return _this;
     }
     D.prototype.bar = function () {
         this.self = this.self1;
diff --git a/tests/baselines/reference/unknownSymbols1.js b/tests/baselines/reference/unknownSymbols1.js
index 46ee4ed02d5..2c2b3ded1b5 100644
--- a/tests/baselines/reference/unknownSymbols1.js
+++ b/tests/baselines/reference/unknownSymbols1.js
@@ -65,6 +65,7 @@ var C4 = (function (_super) {
     function C4() {
         var _this;
         _this = _super.call(this, asdf) || this;
+        return _this;
     }
     return C4;
 }(C3));
diff --git a/tests/baselines/reference/unspecializedConstraints.js b/tests/baselines/reference/unspecializedConstraints.js
index 06d2c4bd6a5..02927bf558d 100644
--- a/tests/baselines/reference/unspecializedConstraints.js
+++ b/tests/baselines/reference/unspecializedConstraints.js
@@ -239,6 +239,7 @@ var ts;
             _this.name = name;
             _this.type = type;
             _this.flags = flags;
+            return _this;
         }
         Property.prototype.equals = function (other) {
             return this.name === other.name &&
@@ -260,6 +261,7 @@ var ts;
             _this.typeParameters = typeParameters;
             _this.parameters = parameters;
             _this.returnType = returnType;
+            return _this;
         }
         Signature.prototype.equalsNoReturn = function (other) {
             return this.parameters.length === other.parameters.length &&
@@ -281,6 +283,7 @@ var ts;
             _this.name = name;
             _this.type = type;
             _this.flags = flags;
+            return _this;
         }
         Parameter.prototype.equals = function (other) {
             return this.name === other.name &&
diff --git a/tests/baselines/reference/validUseOfThisInSuper.js b/tests/baselines/reference/validUseOfThisInSuper.js
index 96802932f12..3a05ff12ee8 100644
--- a/tests/baselines/reference/validUseOfThisInSuper.js
+++ b/tests/baselines/reference/validUseOfThisInSuper.js
@@ -26,6 +26,7 @@ var Super = (function (_super) {
     function Super() {
         var _this;
         _this = _super.call(this, (function () { return _this; })()) || this; // ok since this is not the case: The constructor declares parameter properties or the containing class declares instance member variables with initializers.
+        return _this;
     }
     return Super;
 }(Base));
diff --git a/tests/baselines/reference/varArgsOnConstructorTypes.js b/tests/baselines/reference/varArgsOnConstructorTypes.js
index 04eaa58a196..9c1c8f8c29d 100644
--- a/tests/baselines/reference/varArgsOnConstructorTypes.js
+++ b/tests/baselines/reference/varArgsOnConstructorTypes.js
@@ -45,6 +45,7 @@ define(["require", "exports"], function (require, exports) {
             _this = _super.call(this, element) || this;
             _this.p1 = element;
             _this.p2 = url;
+            return _this;
         }
         return B;
     }(A));

From bab6d6fbb23f28831b4b990ad4c2cc9755240374 Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Fri, 2 Sep 2016 13:03:46 -0700
Subject: [PATCH 08/47] Ensure prologue directives occur first.

---
 src/compiler/transformers/es6.ts | 26 ++++++++++++++++++--------
 1 file changed, 18 insertions(+), 8 deletions(-)

diff --git a/src/compiler/transformers/es6.ts b/src/compiler/transformers/es6.ts
index 886ee1b8e40..8890ac60173 100644
--- a/src/compiler/transformers/es6.ts
+++ b/src/compiler/transformers/es6.ts
@@ -774,10 +774,22 @@ namespace ts {
          * @param hasSynthesizedSuper A value indicating whether the constructor starts with a
          *                            synthesized `super` call.
          */
-        function transformConstructorBody(constructor: ConstructorDeclaration, node: ClassDeclaration | ClassExpression, extendsClauseElement: ExpressionWithTypeArguments, hasSynthesizedSuper: boolean) {
+        function transformConstructorBody(constructor: ConstructorDeclaration | undefined, node: ClassDeclaration | ClassExpression, extendsClauseElement: ExpressionWithTypeArguments, hasSynthesizedSuper: boolean) {
             const statements: Statement[] = [];
             startLexicalEnvironment();
 
+            let statementOffset = -1;
+            if (hasSynthesizedSuper) {
+                // If a super call has already been synthesized,
+                // we're going to assume that we should just transform everything after that.
+                // The assumption is that no prior step in the pipeline has added any prologue directives.
+                statementOffset = 1;
+            }
+            else if (constructor) {
+                // Otherwise, try to emit all potential prologue directives first.
+                statementOffset = addPrologueDirectives(statements, constructor.body.statements, /*ensureUseStrict*/ false, visitor);
+            }
+
             if (constructor) {
                 declareOrCaptureThisForConstructorIfNeeded(statements, constructor, !!extendsClauseElement);
                 addDefaultValueAssignmentsIfNeeded(statements, constructor);
@@ -787,9 +799,11 @@ namespace ts {
             addDefaultSuperCallIfNeeded(statements, constructor, extendsClauseElement, hasSynthesizedSuper);
 
             if (constructor) {
-                const body = saveStateAndInvoke(constructor, hasSynthesizedSuper ? transformConstructorBodyWithSynthesizedSuper : transformConstructorBodyWithoutSynthesizedSuper);
+                Debug.assert(statementOffset >= 0, "statementOffset not initialized correctly!");
+                const body = saveStateAndInvoke(constructor, makeTransformerForConstructorBodyAtOffset(statementOffset));
                 addRange(statements, body);
             }
+
             if (extendsClauseElement) {
                 statements.push(
                     createReturn(
@@ -815,12 +829,8 @@ namespace ts {
             return block;
         }
 
-        function transformConstructorBodyWithSynthesizedSuper(node: ConstructorDeclaration) {
-            return visitNodes(node.body.statements, visitor, isStatement, /*start*/ 1);
-        }
-
-        function transformConstructorBodyWithoutSynthesizedSuper(node: ConstructorDeclaration) {
-            return visitNodes(node.body.statements, visitor, isStatement, /*start*/ 0);
+        function makeTransformerForConstructorBodyAtOffset(offset: number): (c: ConstructorDeclaration) => NodeArray<Statement> {
+            return constructor => visitNodes(constructor.body.statements, visitor, isStatement, /*start*/ offset);
         }
 
         /**

From ce953ceb4569f0c93cda7dc55c46fe4867233bdc Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Fri, 2 Sep 2016 13:04:14 -0700
Subject: [PATCH 09/47] Accepted baselines.

---
 .../emitSuperCallBeforeEmitParameterPropertyDeclaration1.js   | 2 +-
 .../reference/emitSuperCallBeforeEmitPropertyDeclaration1.js  | 2 +-
 ...EmitPropertyDeclarationAndParameterPropertyDeclaration1.js | 2 +-
 tests/baselines/reference/strictModeInConstructor.js          | 4 ++--
 4 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/tests/baselines/reference/emitSuperCallBeforeEmitParameterPropertyDeclaration1.js b/tests/baselines/reference/emitSuperCallBeforeEmitParameterPropertyDeclaration1.js
index b95263464a7..efed8e66a15 100644
--- a/tests/baselines/reference/emitSuperCallBeforeEmitParameterPropertyDeclaration1.js
+++ b/tests/baselines/reference/emitSuperCallBeforeEmitParameterPropertyDeclaration1.js
@@ -28,9 +28,9 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B(x) {
-        var _this;
         "use strict";
         'someStringForEgngInject';
+        var _this;
         _this = _super.call(this) || this;
         _this.x = x;
         return _this;
diff --git a/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclaration1.js b/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclaration1.js
index f078c448b75..6e3d3bfaa1b 100644
--- a/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclaration1.js
+++ b/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclaration1.js
@@ -30,9 +30,9 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this;
         "use strict";
         'someStringForEgngInject';
+        var _this;
         _this = _super.call(this) || this;
         _this.blub = 12;
         return _this;
diff --git a/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclarationAndParameterPropertyDeclaration1.js b/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclarationAndParameterPropertyDeclaration1.js
index e64af9ef862..6559569fe79 100644
--- a/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclarationAndParameterPropertyDeclaration1.js
+++ b/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclarationAndParameterPropertyDeclaration1.js
@@ -28,9 +28,9 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B(x) {
-        var _this;
         "use strict";
         'someStringForEgngInject';
+        var _this;
         _this = _super.call(this) || this;
         _this.x = x;
         _this.blah = 2;
diff --git a/tests/baselines/reference/strictModeInConstructor.js b/tests/baselines/reference/strictModeInConstructor.js
index 4e1c483f1c1..1c33f16a3c6 100644
--- a/tests/baselines/reference/strictModeInConstructor.js
+++ b/tests/baselines/reference/strictModeInConstructor.js
@@ -74,8 +74,8 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this;
         "use strict"; // No error
+        var _this;
         _this = _super.call(this) || this;
         _this.s = 9;
         return _this;
@@ -108,8 +108,8 @@ var D = (function (_super) {
 var Bs = (function (_super) {
     __extends(Bs, _super);
     function Bs() {
-        var _this;
         "use strict"; // No error
+        var _this;
         _this = _super.call(this) || this;
         return _this;
     }

From d6e548b02e3546b70c656fb79e364b1e0cb77bdf Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Fri, 2 Sep 2016 20:04:43 -0700
Subject: [PATCH 10/47] Consolidate '_this' declaration and assignments for
 first statements in constructors.

---
 src/compiler/transformers/es6.ts | 68 +++++++++++++++++++++++++++-----
 1 file changed, 58 insertions(+), 10 deletions(-)

diff --git a/src/compiler/transformers/es6.ts b/src/compiler/transformers/es6.ts
index 8890ac60173..9b703e5ddc4 100644
--- a/src/compiler/transformers/es6.ts
+++ b/src/compiler/transformers/es6.ts
@@ -791,7 +791,8 @@ namespace ts {
             }
 
             if (constructor) {
-                declareOrCaptureThisForConstructorIfNeeded(statements, constructor, !!extendsClauseElement);
+                Debug.assert(statementOffset >= 0, "statementOffset not initialized correctly!");
+                statementOffset = declareOrCaptureThisForConstructorIfNeeded(statements, constructor, !!extendsClauseElement, statementOffset);
                 addDefaultValueAssignmentsIfNeeded(statements, constructor);
                 addRestParameterIfNeeded(statements, constructor, hasSynthesizedSuper);
             }
@@ -799,7 +800,6 @@ namespace ts {
             addDefaultSuperCallIfNeeded(statements, constructor, extendsClauseElement, hasSynthesizedSuper);
 
             if (constructor) {
-                Debug.assert(statementOffset >= 0, "statementOffset not initialized correctly!");
                 const body = saveStateAndInvoke(constructor, makeTransformerForConstructorBodyAtOffset(statementOffset));
                 addRange(statements, body);
             }
@@ -1118,13 +1118,49 @@ namespace ts {
             statements.push(forStatement);
         }
 
-        function declareOrCaptureThisForConstructorIfNeeded(statements: Statement[], ctor: ConstructorDeclaration, hasExtendsClause: boolean) {
+        /**
+         * Declares a `_this` variable for derived classes and for when arrow functions capture `this`.
+         *
+         * @returns The new statement offset into the `statements` array.
+         */
+        function declareOrCaptureThisForConstructorIfNeeded(statements: Statement[], ctor: ConstructorDeclaration, hasExtendsClause: boolean, firstNonPrologue: number) {
             if (hasExtendsClause) {
-                captureThisForNode(statements, ctor, /*initializer*/ undefined);
+                // Most of the time, a 'super' call will be the first real statement in a constructor body.
+                // In these cases, we'd like to transform these into a *single* statement instead of a declaration
+                // followed by an assignment statement for '_this'. For instance, if we emitted without an initializer,
+                // we'd get:
+                //
+                //      var _this;
+                //      _this = super();
+                //
+                // instead of
+                //
+                //      var _this = super();
+                //
+                let initializer: Expression = undefined;
+                let firstStatement: Statement;
+                if (firstNonPrologue < ctor.body.statements.length) {
+                    firstStatement = ctor.body.statements[firstNonPrologue];
+
+                    if (firstStatement.kind === SyntaxKind.ExpressionStatement && isSuperCallExpression((firstStatement as ExpressionStatement).expression)) {
+                        initializer = setOriginalNode(
+                            visitImmediateSuperCallInBody(((firstStatement as ExpressionStatement).expression as CallExpression)),
+                            (firstStatement as ExpressionStatement).expression
+                        );
+                    }
+                }
+                captureThisForNode(statements, ctor, /*initializer*/ initializer, firstStatement);
+
+                // We're actually skipping an extra statement. Signal this to the caller.
+                if (initializer) {
+                    return firstNonPrologue + 1;
+                }
             }
             else {
                 addCaptureThisForNodeIfNeeded(statements, ctor);
             }
+
+            return firstNonPrologue;
         }
 
         /**
@@ -1139,7 +1175,9 @@ namespace ts {
             }
         }
 
-        function captureThisForNode(statements: Statement[], node: Node, initializer: Expression | undefined) {
+        function captureThisForNode(statements: Statement[], node: Node, initializer: Expression | undefined): void;
+        function captureThisForNode(statements: Statement[], node: Node, initializer: Expression | undefined, originalStatement: Statement): void;
+        function captureThisForNode(statements: Statement[], node: Node, initializer: Expression | undefined, originalStatement?: Statement): void {
             enableSubstitutionsForCapturedThis();
             const captureThisStatement = createVariableStatement(
                 /*modifiers*/ undefined,
@@ -1149,7 +1187,8 @@ namespace ts {
                         /*type*/ undefined,
                         initializer
                     )
-                ])
+                ]),
+                originalStatement
             );
 
             setNodeEmitFlags(captureThisStatement, NodeEmitFlags.NoComments | NodeEmitFlags.CustomPrologue);
@@ -2520,7 +2559,15 @@ namespace ts {
          *
          * @param node a CallExpression.
          */
-        function visitCallExpression(node: CallExpression): CallExpression | BinaryExpression {
+        function visitCallExpression(node: CallExpression) {
+            return visitCallExpressionWithPotentialCapturedThisAssignment(node, /*assignToCapturedThis*/ true);
+        }
+
+        function visitImmediateSuperCallInBody(node: CallExpression) {
+            return visitCallExpressionWithPotentialCapturedThisAssignment(node, /*assignToCapturedThis*/ false);
+        }
+
+        function visitCallExpressionWithPotentialCapturedThisAssignment(node: CallExpression, assignToCapturedThis: boolean): CallExpression | BinaryExpression {
             // We are here either because SuperKeyword was used somewhere in the expression, or
             // because we contain a SpreadElementExpression.
 
@@ -2572,13 +2619,14 @@ namespace ts {
             if (node.expression.kind === SyntaxKind.SuperKeyword) {
                 const actualThis = createThis();
                 setNodeEmitFlags(actualThis, NodeEmitFlags.NoSubstitution);
-                return createAssignment(
-                    createIdentifier("_this"),
+                const initializer =
                     createLogicalOr(
                         resultingCall,
                         actualThis
                     )
-                );
+                return assignToCapturedThis
+                    ? createAssignment(createIdentifier("_this"), initializer)
+                    : initializer
             }
             return resultingCall;
         }

From 11bc6c470f5dd09dc83fbf8ac269f0c8bc023ad0 Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Sat, 3 Sep 2016 00:16:43 -0700
Subject: [PATCH 11/47] Fixed issue where last function context & parent node
 wasn't being preserved.

This came up when a `super()` call was nested in another constructor body.
Current logic in the transform says that if the last containing non-arrow
function body is non-static, and the current parent isn't a call expression,
the call target of a `super` call will become `_super.prototype` instead
of `super`.

If the state is not saved, the containing arrow function and parent
are not saved, and the information for this check won't be accurate.
---
 src/compiler/transformers/es6.ts | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/compiler/transformers/es6.ts b/src/compiler/transformers/es6.ts
index 9b703e5ddc4..85838112fc3 100644
--- a/src/compiler/transformers/es6.ts
+++ b/src/compiler/transformers/es6.ts
@@ -1143,9 +1143,10 @@ namespace ts {
                     firstStatement = ctor.body.statements[firstNonPrologue];
 
                     if (firstStatement.kind === SyntaxKind.ExpressionStatement && isSuperCallExpression((firstStatement as ExpressionStatement).expression)) {
+                        const superCall = (firstStatement as ExpressionStatement).expression as CallExpression;
                         initializer = setOriginalNode(
-                            visitImmediateSuperCallInBody(((firstStatement as ExpressionStatement).expression as CallExpression)),
-                            (firstStatement as ExpressionStatement).expression
+                            saveStateAndInvoke(superCall, visitImmediateSuperCallInBody),
+                            superCall
                         );
                     }
                 }

From d8846dd495d03697ee598d6c887f55eac61789ef Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Sat, 3 Sep 2016 00:26:02 -0700
Subject: [PATCH 12/47] Accepted baselines.

---
 tests/baselines/reference/abstractProperty.js |   3 +-
 .../reference/abstractPropertyNegative.js     |   9 +-
 .../accessOverriddenBaseClassMember1.js       |   3 +-
 ...aliasUsageInTypeArgumentOfExtendsClause.js |   3 +-
 .../reference/arrowFunctionContexts.js        |   6 +-
 .../reference/assignmentLHSIsValue.js         |   3 +-
 tests/baselines/reference/autolift4.js        |   3 +-
 tests/baselines/reference/baseCheck.js        |  15 +-
 .../reference/bestCommonTypeOfTuple2.js       |   3 +-
 tests/baselines/reference/callWithSpread.js   |   3 +-
 .../reference/captureThisInSuperCall.js       |   3 +-
 .../reference/checkForObjectTooStrict.js      |   6 +-
 .../checkSuperCallBeforeThisAccessing1.js     |   3 +-
 .../checkSuperCallBeforeThisAccessing5.js     |   3 +-
 .../checkSuperCallBeforeThisAccessing7.js     |   3 +-
 .../classConstructorAccessibility2.js         |   9 +-
 ...classConstructorParametersAccessibility.js |   3 +-
 ...lassConstructorParametersAccessibility2.js |   3 +-
 ...lassConstructorParametersAccessibility3.js |   3 +-
 tests/baselines/reference/classExpression3.js |   6 +-
 .../reference/classExtendingClassLikeType.js  |   9 +-
 tests/baselines/reference/classExtendsNull.js |   3 +-
 .../reference/classSideInheritance2.js        |   3 +-
 .../reference/classSideInheritance3.js        |   6 +-
 tests/baselines/reference/classUpdateTests.js |  15 +-
 ...isionSuperAndLocalFunctionInConstructor.js |   6 +-
 ...ollisionSuperAndLocalFunctionInProperty.js |   3 +-
 .../collisionSuperAndLocalVarInConstructor.js |   6 +-
 .../collisionSuperAndLocalVarInProperty.js    |   3 +-
 .../reference/collisionSuperAndParameter.js   |   6 +-
 ...perAndPropertyNameAsConstuctorParameter.js |  12 +-
 .../reference/commentsInheritance.js          |   3 +-
 .../reference/compoundAssignmentLHSIsValue.js |   3 +-
 ...poundExponentiationAssignmentLHSIsValue.js |   3 +-
 .../reference/computedPropertyNames28_ES5.js  |   3 +-
 .../reference/computedPropertyNames30_ES5.js  |   3 +-
 tests/baselines/reference/constructorArgs.js  |   3 +-
 ...ctorFunctionTypeIsAssignableToBaseType2.js |   6 +-
 .../reference/constructorOverloads2.js        |   3 +-
 .../reference/declFileGenericType2.js         |   6 +-
 .../reference/decoratorOnClassConstructor2.js |   3 +-
 .../reference/decoratorOnClassConstructor3.js |   3 +-
 .../derivedClassOverridesPrivateFunction1.js  |   3 +-
 .../derivedClassOverridesProtectedMembers.js  |   3 +-
 .../derivedClassOverridesProtectedMembers2.js |   3 +-
 .../derivedClassOverridesProtectedMembers3.js |  30 ++--
 .../derivedClassOverridesPublicMembers.js     |   3 +-
 .../derivedClassParameterProperties.js        |  12 +-
 ...dClassSuperCallsInNonConstructorMembers.js |   3 +-
 .../derivedClassSuperCallsWithThisArg.js      |  12 +-
 .../derivedClassWithoutExplicitConstructor.js |   6 +-
 ...derivedClassWithoutExplicitConstructor2.js |   6 +-
 ...derivedClassWithoutExplicitConstructor3.js |  12 +-
 .../destructuringParameterDeclaration5.js     |   6 +-
 ...BeforeEmitParameterPropertyDeclaration1.js |   3 +-
 ...SuperCallBeforeEmitPropertyDeclaration1.js |   3 +-
 ...arationAndParameterPropertyDeclaration1.js |   3 +-
 tests/baselines/reference/errorSuperCalls.js  |   3 +-
 .../reference/errorSuperPropertyAccess.js     |   6 +-
 tests/baselines/reference/es6ClassTest.js     |   3 +-
 tests/baselines/reference/es6ClassTest2.js    |   3 +-
 ...cClassPropertyInheritanceSpecialization.js |   3 +-
 ...genericConstraintOnExtendedBuiltinTypes.js |   3 +-
 ...enericConstraintOnExtendedBuiltinTypes2.js |   3 +-
 ...ericRecursiveImplicitConstructorErrors3.js |   3 +-
 .../reference/genericTypeConstraints.js       |   3 +-
 .../interfaceExtendsClassWithPrivate2.js      |   6 +-
 tests/baselines/reference/lift.js             |   3 +-
 .../missingPropertiesOfClassExpression.js     |   3 +-
 ...objectCreationOfElementAccessExpression.js |  18 +--
 tests/baselines/reference/optionalMethods.js  |   3 +-
 .../reference/optionalParamArgsTest.js        |   3 +-
 .../reference/optionalParameterProperty.js    |   3 +-
 .../overloadOnConstConstraintChecks4.js       |   3 +-
 tests/baselines/reference/parserAstSpans1.js  |   6 +-
 .../baselines/reference/parserRealSource10.js |  18 +--
 .../baselines/reference/parserRealSource11.js | 144 ++++++------------
 tests/baselines/reference/parserharness.js    |   9 +-
 .../privateInstanceMemberAccessibility.js     |   3 +-
 .../privateStaticMemberAccessibility.js       |   3 +-
 .../readonlyConstructorAssignment.js          |   9 +-
 .../reference/returnInConstructor1.js         |   6 +-
 tests/baselines/reference/scopeTests.js       |   3 +-
 ...sWithDefaultConstructorAndExtendsClause.js |   3 +-
 ...hDefaultConstructorAndExtendsClause.js.map |   2 +-
 ...tConstructorAndExtendsClause.sourcemap.txt |  54 ++++---
 .../baselines/reference/staticInheritance.js  |   3 +-
 .../reference/strictModeInConstructor.js      |  12 +-
 tests/baselines/reference/superAccess2.js     |   3 +-
 .../reference/superCallArgsMustMatch.js       |   4 +-
 .../superCallBeforeThisAccessing1.js          |   3 +-
 .../superCallBeforeThisAccessing2.js          |   3 +-
 .../superCallBeforeThisAccessing4.js          |   3 +-
 .../superCallBeforeThisAccessing6.js          |   3 +-
 ...allFromClassThatDerivesFromGenericType1.js |   3 +-
 ...allFromClassThatDerivesFromGenericType2.js |   3 +-
 ...eButWithIncorrectNumberOfTypeArguments1.js |   3 +-
 ...sFromGenericTypeButWithNoTypeArguments1.js |   3 +-
 ...ivesNonGenericTypeButWithTypeArguments1.js |   3 +-
 .../reference/superCallInNonStaticMethod.js   |   3 +-
 .../superCallInsideClassDeclaration.js        |   3 +-
 .../superCallInsideClassExpression.js         |   3 +-
 .../reference/superCallOutsideConstructor.js  |   3 +-
 .../superCallParameterContextualTyping1.js    |   3 +-
 .../superCallParameterContextualTyping2.js    |   3 +-
 .../superCallParameterContextualTyping3.js    |   4 +-
 tests/baselines/reference/superCalls.js       |   3 +-
 tests/baselines/reference/superErrors.js      |   3 +-
 tests/baselines/reference/superInLambdas.js   |  12 +-
 .../reference/superPropertyAccess1.js         |   3 +-
 .../reference/superPropertyAccess2.js         |   3 +-
 .../reference/superPropertyAccessNoError.js   |   3 +-
 .../reference/superPropertyAccess_ES5.js      |   3 +-
 .../superWithGenericSpecialization.js         |   3 +-
 .../baselines/reference/superWithGenerics.js  |   3 +-
 .../reference/targetTypeBaseCalls.js          |   3 +-
 .../reference/thisInInvalidContexts.js        |   6 +-
 .../thisInInvalidContextsExternalModule.js    |   6 +-
 tests/baselines/reference/thisInSuperCall.js  |   9 +-
 tests/baselines/reference/thisInSuperCall1.js |   3 +-
 tests/baselines/reference/thisInSuperCall2.js |   6 +-
 tests/baselines/reference/thisInSuperCall3.js |   3 +-
 .../baselines/reference/tsxDynamicTagName5.js |   3 +-
 .../baselines/reference/tsxDynamicTagName7.js |   3 +-
 .../baselines/reference/tsxDynamicTagName8.js |   3 +-
 .../baselines/reference/tsxDynamicTagName9.js |   3 +-
 .../reference/typeGuardOfFormThisMember.js    |   3 +-
 .../typeGuardOfFormThisMemberErrors.js        |   3 +-
 .../baselines/reference/typeRelationships.js  |   3 +-
 tests/baselines/reference/unknownSymbols1.js  |   3 +-
 .../reference/unspecializedConstraints.js     |   9 +-
 .../reference/validUseOfThisInSuper.js        |   3 +-
 .../reference/varArgsOnConstructorTypes.js    |   3 +-
 133 files changed, 285 insertions(+), 541 deletions(-)

diff --git a/tests/baselines/reference/abstractProperty.js b/tests/baselines/reference/abstractProperty.js
index 292213ead53..fb7deaa09dd 100644
--- a/tests/baselines/reference/abstractProperty.js
+++ b/tests/baselines/reference/abstractProperty.js
@@ -35,8 +35,7 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.raw = "edge";
         _this.ro = "readonly please";
         return _this;
diff --git a/tests/baselines/reference/abstractPropertyNegative.js b/tests/baselines/reference/abstractPropertyNegative.js
index 28ada310ef4..5a4c24fe233 100644
--- a/tests/baselines/reference/abstractPropertyNegative.js
+++ b/tests/baselines/reference/abstractPropertyNegative.js
@@ -57,8 +57,7 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.ro = "readonly please";
         return _this;
     }
@@ -79,8 +78,7 @@ var WrongTypeProperty = (function () {
 var WrongTypePropertyImpl = (function (_super) {
     __extends(WrongTypePropertyImpl, _super);
     function WrongTypePropertyImpl() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.num = "nope, wrong";
         return _this;
     }
@@ -107,8 +105,7 @@ var WrongTypeAccessorImpl = (function (_super) {
 var WrongTypeAccessorImpl2 = (function (_super) {
     __extends(WrongTypeAccessorImpl2, _super);
     function WrongTypeAccessorImpl2() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.num = "nope, wrong";
         return _this;
     }
diff --git a/tests/baselines/reference/accessOverriddenBaseClassMember1.js b/tests/baselines/reference/accessOverriddenBaseClassMember1.js
index 65431a2f778..02d092dfd39 100644
--- a/tests/baselines/reference/accessOverriddenBaseClassMember1.js
+++ b/tests/baselines/reference/accessOverriddenBaseClassMember1.js
@@ -34,8 +34,7 @@ var Point = (function () {
 var ColoredPoint = (function (_super) {
     __extends(ColoredPoint, _super);
     function ColoredPoint(x, y, color) {
-        var _this;
-        _this = _super.call(this, x, y) || this;
+        var _this = _super.call(this, x, y) || this;
         _this.color = color;
         return _this;
     }
diff --git a/tests/baselines/reference/aliasUsageInTypeArgumentOfExtendsClause.js b/tests/baselines/reference/aliasUsageInTypeArgumentOfExtendsClause.js
index 8af9c702654..91c6ca2c53f 100644
--- a/tests/baselines/reference/aliasUsageInTypeArgumentOfExtendsClause.js
+++ b/tests/baselines/reference/aliasUsageInTypeArgumentOfExtendsClause.js
@@ -65,8 +65,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.x = moduleA;
         return _this;
     }
diff --git a/tests/baselines/reference/arrowFunctionContexts.js b/tests/baselines/reference/arrowFunctionContexts.js
index 660208cb0c1..1af0797b41f 100644
--- a/tests/baselines/reference/arrowFunctionContexts.js
+++ b/tests/baselines/reference/arrowFunctionContexts.js
@@ -116,8 +116,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this;
-        _this = _super.call(this, function () { return _this; }) || this;
+        var _this = _super.call(this, function () { return _this; }) || this;
         return _this;
     }
     return Derived;
@@ -159,8 +158,7 @@ var M2;
     var Derived = (function (_super) {
         __extends(Derived, _super);
         function Derived() {
-            var _this;
-            _this = _super.call(this, function () { return _this; }) || this;
+            var _this = _super.call(this, function () { return _this; }) || this;
             return _this;
         }
         return Derived;
diff --git a/tests/baselines/reference/assignmentLHSIsValue.js b/tests/baselines/reference/assignmentLHSIsValue.js
index 52d14cbe536..ab3f80eff21 100644
--- a/tests/baselines/reference/assignmentLHSIsValue.js
+++ b/tests/baselines/reference/assignmentLHSIsValue.js
@@ -118,8 +118,7 @@ value;
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _super.prototype. = value;
         return _this;
     }
diff --git a/tests/baselines/reference/autolift4.js b/tests/baselines/reference/autolift4.js
index 0638efab0b3..1c29bfeeff7 100644
--- a/tests/baselines/reference/autolift4.js
+++ b/tests/baselines/reference/autolift4.js
@@ -43,8 +43,7 @@ Point.origin = new Point(0, 0);
 var Point3D = (function (_super) {
     __extends(Point3D, _super);
     function Point3D(x, y, z, m) {
-        var _this;
-        _this = _super.call(this, x, y) || this;
+        var _this = _super.call(this, x, y) || this;
         _this.z = z;
         return _this;
     }
diff --git a/tests/baselines/reference/baseCheck.js b/tests/baselines/reference/baseCheck.js
index 832830ae864..623cd152b9a 100644
--- a/tests/baselines/reference/baseCheck.js
+++ b/tests/baselines/reference/baseCheck.js
@@ -43,8 +43,7 @@ var C = (function () {
 var ELoc = (function (_super) {
     __extends(ELoc, _super);
     function ELoc(x) {
-        var _this;
-        _this = _super.call(this, 0, x) || this;
+        var _this = _super.call(this, 0, x) || this;
         return _this;
     }
     return ELoc;
@@ -52,8 +51,7 @@ var ELoc = (function (_super) {
 var ELocVar = (function (_super) {
     __extends(ELocVar, _super);
     function ELocVar(x) {
-        var _this;
-        _this = _super.call(this, 0, loc) || this;
+        var _this = _super.call(this, 0, loc) || this;
         return _this;
     }
     ELocVar.prototype.m = function () {
@@ -64,8 +62,7 @@ var ELocVar = (function (_super) {
 var D = (function (_super) {
     __extends(D, _super);
     function D(z) {
-        var _this;
-        _this = _super.call(this, _this.z) || this;
+        var _this = _super.call(this, _this.z) || this;
         _this.z = z;
         return _this;
     }
@@ -74,8 +71,7 @@ var D = (function (_super) {
 var E = (function (_super) {
     __extends(E, _super);
     function E(z) {
-        var _this;
-        _this = _super.call(this, 0, _this.z) || this;
+        var _this = _super.call(this, 0, _this.z) || this;
         _this.z = z;
         return _this;
     }
@@ -84,8 +80,7 @@ var E = (function (_super) {
 var F = (function (_super) {
     __extends(F, _super);
     function F(z) {
-        var _this;
-        _this = _super.call(this, "hello", _this.z) || this;
+        var _this = _super.call(this, "hello", _this.z) || this;
         _this.z = z;
         return _this;
     }
diff --git a/tests/baselines/reference/bestCommonTypeOfTuple2.js b/tests/baselines/reference/bestCommonTypeOfTuple2.js
index 8213733b753..d71b6f17abf 100644
--- a/tests/baselines/reference/bestCommonTypeOfTuple2.js
+++ b/tests/baselines/reference/bestCommonTypeOfTuple2.js
@@ -60,8 +60,7 @@ var C1 = (function () {
 var D1 = (function (_super) {
     __extends(D1, _super);
     function D1() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.i = "bar";
         return _this;
     }
diff --git a/tests/baselines/reference/callWithSpread.js b/tests/baselines/reference/callWithSpread.js
index 48af58edf65..161eb36dbcf 100644
--- a/tests/baselines/reference/callWithSpread.js
+++ b/tests/baselines/reference/callWithSpread.js
@@ -99,8 +99,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this;
-        _this = _super.call(this, 1, 2) || this;
+        var _this = _super.call(this, 1, 2) || this;
         _this = _super.apply(this, [1, 2].concat(a)) || this;
         return _this;
     }
diff --git a/tests/baselines/reference/captureThisInSuperCall.js b/tests/baselines/reference/captureThisInSuperCall.js
index 2d39722548d..069871f598e 100644
--- a/tests/baselines/reference/captureThisInSuperCall.js
+++ b/tests/baselines/reference/captureThisInSuperCall.js
@@ -22,8 +22,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this;
-        _this = _super.call(this, { test: function () { return _this.someMethod(); } }) || this;
+        var _this = _super.call(this, { test: function () { return _this.someMethod(); } }) || this;
         return _this;
     }
     B.prototype.someMethod = function () { };
diff --git a/tests/baselines/reference/checkForObjectTooStrict.js b/tests/baselines/reference/checkForObjectTooStrict.js
index 8c0cfc104d2..156608bd6b5 100644
--- a/tests/baselines/reference/checkForObjectTooStrict.js
+++ b/tests/baselines/reference/checkForObjectTooStrict.js
@@ -49,8 +49,7 @@ var Foo;
 var Bar = (function (_super) {
     __extends(Bar, _super);
     function Bar() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         return _this;
     }
     return Bar;
@@ -58,8 +57,7 @@ var Bar = (function (_super) {
 var Baz = (function (_super) {
     __extends(Baz, _super);
     function Baz() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         return _this;
     }
     return Baz;
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing1.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing1.js
index a54f82ab9fa..8ced6fce500 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing1.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing1.js
@@ -24,8 +24,7 @@ var Based = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _this;
         _this.x = 10;
         var that = _this;
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing5.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing5.js
index e365678ee0c..3174bebd11d 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing5.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing5.js
@@ -25,8 +25,7 @@ var Based = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this;
-        _this = _super.call(this, _this.x) || this;
+        var _this = _super.call(this, _this.x) || this;
         return _this;
     }
     return Derived;
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing7.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing7.js
index 7ba43de005b..364aed4d4b0 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing7.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing7.js
@@ -23,8 +23,7 @@ var Base = (function () {
 var Super = (function (_super) {
     __extends(Super, _super);
     function Super() {
-        var _this;
-        _this = _super.call(this, (function () { return _this; })) || this; // No error
+        var _this = _super.call(this, (function () { return _this; })) || this;
         return _this;
     }
     return Super;
diff --git a/tests/baselines/reference/classConstructorAccessibility2.js b/tests/baselines/reference/classConstructorAccessibility2.js
index 8a81d469fb8..ef637611e8d 100644
--- a/tests/baselines/reference/classConstructorAccessibility2.js
+++ b/tests/baselines/reference/classConstructorAccessibility2.js
@@ -77,8 +77,7 @@ var BaseC = (function () {
 var DerivedA = (function (_super) {
     __extends(DerivedA, _super);
     function DerivedA(x) {
-        var _this;
-        _this = _super.call(this, x) || this;
+        var _this = _super.call(this, x) || this;
         _this.x = x;
         return _this;
     }
@@ -90,8 +89,7 @@ var DerivedA = (function (_super) {
 var DerivedB = (function (_super) {
     __extends(DerivedB, _super);
     function DerivedB(x) {
-        var _this;
-        _this = _super.call(this, x) || this;
+        var _this = _super.call(this, x) || this;
         _this.x = x;
         return _this;
     }
@@ -103,8 +101,7 @@ var DerivedB = (function (_super) {
 var DerivedC = (function (_super) {
     __extends(DerivedC, _super);
     function DerivedC(x) {
-        var _this;
-        _this = _super.call(this, x) || this;
+        var _this = _super.call(this, x) || this;
         _this.x = x;
         return _this;
     }
diff --git a/tests/baselines/reference/classConstructorParametersAccessibility.js b/tests/baselines/reference/classConstructorParametersAccessibility.js
index 214815f4976..e0e75bcfeeb 100644
--- a/tests/baselines/reference/classConstructorParametersAccessibility.js
+++ b/tests/baselines/reference/classConstructorParametersAccessibility.js
@@ -59,8 +59,7 @@ c3.p; // protected, error
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived(p) {
-        var _this;
-        _this = _super.call(this, p) || this;
+        var _this = _super.call(this, p) || this;
         _this.p; // OK
         return _this;
     }
diff --git a/tests/baselines/reference/classConstructorParametersAccessibility2.js b/tests/baselines/reference/classConstructorParametersAccessibility2.js
index 7c714aa4c03..84da66c3e3c 100644
--- a/tests/baselines/reference/classConstructorParametersAccessibility2.js
+++ b/tests/baselines/reference/classConstructorParametersAccessibility2.js
@@ -59,8 +59,7 @@ c3.p; // protected, error
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived(p) {
-        var _this;
-        _this = _super.call(this, p) || this;
+        var _this = _super.call(this, p) || this;
         _this.p; // OK
         return _this;
     }
diff --git a/tests/baselines/reference/classConstructorParametersAccessibility3.js b/tests/baselines/reference/classConstructorParametersAccessibility3.js
index 275f3920538..db9f94cf0fb 100644
--- a/tests/baselines/reference/classConstructorParametersAccessibility3.js
+++ b/tests/baselines/reference/classConstructorParametersAccessibility3.js
@@ -28,8 +28,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived(p) {
-        var _this;
-        _this = _super.call(this, p) || this;
+        var _this = _super.call(this, p) || this;
         _this.p = p;
         _this.p; // OK
         return _this;
diff --git a/tests/baselines/reference/classExpression3.js b/tests/baselines/reference/classExpression3.js
index 3c53d728233..c0376c54c27 100644
--- a/tests/baselines/reference/classExpression3.js
+++ b/tests/baselines/reference/classExpression3.js
@@ -15,8 +15,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(class_1, _super);
     function class_1() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.c = 3;
         return _this;
     }
@@ -24,8 +23,7 @@ var C = (function (_super) {
 }((function (_super) {
     __extends(class_2, _super);
     function class_2() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.b = 2;
         return _this;
     }
diff --git a/tests/baselines/reference/classExtendingClassLikeType.js b/tests/baselines/reference/classExtendingClassLikeType.js
index 32d7fff0cbd..fdda53a381f 100644
--- a/tests/baselines/reference/classExtendingClassLikeType.js
+++ b/tests/baselines/reference/classExtendingClassLikeType.js
@@ -76,8 +76,7 @@ var D0 = (function (_super) {
 var D1 = (function (_super) {
     __extends(D1, _super);
     function D1() {
-        var _this;
-        _this = _super.call(this, "abc", "def") || this;
+        var _this = _super.call(this, "abc", "def") || this;
         _this.x = "x";
         _this.y = "y";
         return _this;
@@ -87,8 +86,7 @@ var D1 = (function (_super) {
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        var _this;
-        _this = _super.call(this, 10) || this;
+        var _this = _super.call(this, 10) || this;
         _this = _super.call(this, 10, 20) || this;
         _this.x = 1;
         _this.y = 2;
@@ -99,8 +97,7 @@ var D2 = (function (_super) {
 var D3 = (function (_super) {
     __extends(D3, _super);
     function D3() {
-        var _this;
-        _this = _super.call(this, "abc", 42) || this;
+        var _this = _super.call(this, "abc", 42) || this;
         _this.x = "x";
         _this.y = 2;
         return _this;
diff --git a/tests/baselines/reference/classExtendsNull.js b/tests/baselines/reference/classExtendsNull.js
index 301dee7f705..a820b525aab 100644
--- a/tests/baselines/reference/classExtendsNull.js
+++ b/tests/baselines/reference/classExtendsNull.js
@@ -21,8 +21,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         return Object.create(null);
         return _this;
     }
diff --git a/tests/baselines/reference/classSideInheritance2.js b/tests/baselines/reference/classSideInheritance2.js
index 1af6b6f846c..475f9bd4ceb 100644
--- a/tests/baselines/reference/classSideInheritance2.js
+++ b/tests/baselines/reference/classSideInheritance2.js
@@ -29,8 +29,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var SubText = (function (_super) {
     __extends(SubText, _super);
     function SubText(text, span) {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         return _this;
     }
     return SubText;
diff --git a/tests/baselines/reference/classSideInheritance3.js b/tests/baselines/reference/classSideInheritance3.js
index fda7b0b0848..361378c3ff5 100644
--- a/tests/baselines/reference/classSideInheritance3.js
+++ b/tests/baselines/reference/classSideInheritance3.js
@@ -33,8 +33,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B(x, data) {
-        var _this;
-        _this = _super.call(this, x) || this;
+        var _this = _super.call(this, x) || this;
         _this.data = data;
         return _this;
     }
@@ -43,8 +42,7 @@ var B = (function (_super) {
 var C = (function (_super) {
     __extends(C, _super);
     function C(x) {
-        var _this;
-        _this = _super.call(this, x) || this;
+        var _this = _super.call(this, x) || this;
         return _this;
     }
     return C;
diff --git a/tests/baselines/reference/classUpdateTests.js b/tests/baselines/reference/classUpdateTests.js
index 2d7ecc3c190..9809966c4c2 100644
--- a/tests/baselines/reference/classUpdateTests.js
+++ b/tests/baselines/reference/classUpdateTests.js
@@ -157,8 +157,7 @@ var D = (function () {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.p1 = 0;
         return _this;
     }
@@ -175,8 +174,7 @@ var F = (function (_super) {
 var G = (function (_super) {
     __extends(G, _super);
     function G() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _this.p1 = 0;
         return _this;
     } // NO ERROR
@@ -191,8 +189,7 @@ var H = (function () {
 var I = (function (_super) {
     __extends(I, _super);
     function I() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         return _this;
     } // ERROR - no super call allowed
     return I;
@@ -200,8 +197,7 @@ var I = (function (_super) {
 var J = (function (_super) {
     __extends(J, _super);
     function J(p1) {
-        var _this;
-        _this = _super.call(this) || this; // NO ERROR
+        var _this = _super.call(this) || this;
         _this.p1 = p1;
         return _this;
     }
@@ -221,8 +217,7 @@ var K = (function (_super) {
 var L = (function (_super) {
     __extends(L, _super);
     function L(p1) {
-        var _this;
-        _this = _super.call(this) || this; // NO ERROR
+        var _this = _super.call(this) || this;
         _this.p1 = p1;
         return _this;
     }
diff --git a/tests/baselines/reference/collisionSuperAndLocalFunctionInConstructor.js b/tests/baselines/reference/collisionSuperAndLocalFunctionInConstructor.js
index 5f2a5e89301..d4a22b731f2 100644
--- a/tests/baselines/reference/collisionSuperAndLocalFunctionInConstructor.js
+++ b/tests/baselines/reference/collisionSuperAndLocalFunctionInConstructor.js
@@ -42,8 +42,7 @@ var Foo = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         function _super() {
         }
         return _this;
@@ -53,8 +52,7 @@ var b = (function (_super) {
 var c = (function (_super) {
     __extends(c, _super);
     function c() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         var x = function () {
             function _super() {
             }
diff --git a/tests/baselines/reference/collisionSuperAndLocalFunctionInProperty.js b/tests/baselines/reference/collisionSuperAndLocalFunctionInProperty.js
index a6893c6a57a..67b7f0e3991 100644
--- a/tests/baselines/reference/collisionSuperAndLocalFunctionInProperty.js
+++ b/tests/baselines/reference/collisionSuperAndLocalFunctionInProperty.js
@@ -40,8 +40,7 @@ var Foo = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.prop2 = {
             doStuff: function () {
                 function _super() {
diff --git a/tests/baselines/reference/collisionSuperAndLocalVarInConstructor.js b/tests/baselines/reference/collisionSuperAndLocalVarInConstructor.js
index d799c783503..e3069352c08 100644
--- a/tests/baselines/reference/collisionSuperAndLocalVarInConstructor.js
+++ b/tests/baselines/reference/collisionSuperAndLocalVarInConstructor.js
@@ -36,8 +36,7 @@ var Foo = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         var _super = 10; // Should be error 
         return _this;
     }
@@ -46,8 +45,7 @@ var b = (function (_super) {
 var c = (function (_super) {
     __extends(c, _super);
     function c() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         var x = function () {
             var _super = 10; // Should be error
         };
diff --git a/tests/baselines/reference/collisionSuperAndLocalVarInProperty.js b/tests/baselines/reference/collisionSuperAndLocalVarInProperty.js
index 4bb4f6a5a8b..d793e022c6b 100644
--- a/tests/baselines/reference/collisionSuperAndLocalVarInProperty.js
+++ b/tests/baselines/reference/collisionSuperAndLocalVarInProperty.js
@@ -38,8 +38,7 @@ var Foo = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.prop2 = {
             doStuff: function () {
                 var _super = 10; // Should be error 
diff --git a/tests/baselines/reference/collisionSuperAndParameter.js b/tests/baselines/reference/collisionSuperAndParameter.js
index 6ed47a1b3c1..750ae15ef0a 100644
--- a/tests/baselines/reference/collisionSuperAndParameter.js
+++ b/tests/baselines/reference/collisionSuperAndParameter.js
@@ -94,8 +94,7 @@ var Foo = (function () {
 var Foo2 = (function (_super) {
     __extends(Foo2, _super);
     function Foo2(_super) {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _this.prop4 = {
             doStuff: function (_super) {
             }
@@ -125,8 +124,7 @@ var Foo2 = (function (_super) {
 var Foo4 = (function (_super) {
     __extends(Foo4, _super);
     function Foo4(_super) {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         return _this;
     }
     Foo4.prototype.y = function (_super) {
diff --git a/tests/baselines/reference/collisionSuperAndPropertyNameAsConstuctorParameter.js b/tests/baselines/reference/collisionSuperAndPropertyNameAsConstuctorParameter.js
index 2d3709fa878..269881b3b90 100644
--- a/tests/baselines/reference/collisionSuperAndPropertyNameAsConstuctorParameter.js
+++ b/tests/baselines/reference/collisionSuperAndPropertyNameAsConstuctorParameter.js
@@ -44,8 +44,7 @@ var a = (function () {
 var b1 = (function (_super) {
     __extends(b1, _super);
     function b1(_super) {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         return _this;
     }
     return b1;
@@ -53,8 +52,7 @@ var b1 = (function (_super) {
 var b2 = (function (_super) {
     __extends(b2, _super);
     function b2(_super) {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _this._super = _super;
         return _this;
     }
@@ -63,8 +61,7 @@ var b2 = (function (_super) {
 var b3 = (function (_super) {
     __extends(b3, _super);
     function b3(_super) {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         return _this;
     }
     return b3;
@@ -72,8 +69,7 @@ var b3 = (function (_super) {
 var b4 = (function (_super) {
     __extends(b4, _super);
     function b4(_super) {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _this._super = _super;
         return _this;
     }
diff --git a/tests/baselines/reference/commentsInheritance.js b/tests/baselines/reference/commentsInheritance.js
index 370ee0d246c..294f3a33690 100644
--- a/tests/baselines/reference/commentsInheritance.js
+++ b/tests/baselines/reference/commentsInheritance.js
@@ -227,8 +227,7 @@ var c2 = (function () {
 var c3 = (function (_super) {
     __extends(c3, _super);
     function c3() {
-        var _this;
-        _this = _super.call(this, 10) || this;
+        var _this = _super.call(this, 10) || this;
         return _this;
     }
     /** c3 f1*/
diff --git a/tests/baselines/reference/compoundAssignmentLHSIsValue.js b/tests/baselines/reference/compoundAssignmentLHSIsValue.js
index dfbdf31c3d1..bfea11911bf 100644
--- a/tests/baselines/reference/compoundAssignmentLHSIsValue.js
+++ b/tests/baselines/reference/compoundAssignmentLHSIsValue.js
@@ -197,8 +197,7 @@ value;
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _super.prototype. *= value;
         _super.prototype. += value;
         return _this;
diff --git a/tests/baselines/reference/compoundExponentiationAssignmentLHSIsValue.js b/tests/baselines/reference/compoundExponentiationAssignmentLHSIsValue.js
index da670472b47..c8fb8c6a222 100644
--- a/tests/baselines/reference/compoundExponentiationAssignmentLHSIsValue.js
+++ b/tests/baselines/reference/compoundExponentiationAssignmentLHSIsValue.js
@@ -139,8 +139,7 @@ _a = Math.pow(['', ''], value), '' = _a[0], '' = _a[1];
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         (_a = _super.prototype). = Math.pow(_a., value);
         var _a;
         return _this;
diff --git a/tests/baselines/reference/computedPropertyNames28_ES5.js b/tests/baselines/reference/computedPropertyNames28_ES5.js
index 8152394cbf8..ab765c56dd7 100644
--- a/tests/baselines/reference/computedPropertyNames28_ES5.js
+++ b/tests/baselines/reference/computedPropertyNames28_ES5.js
@@ -24,8 +24,7 @@ var Base = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         var obj = (_a = {},
             _a[(_this = _super.call(this) || this, "prop")] = function () { },
             _a);
diff --git a/tests/baselines/reference/computedPropertyNames30_ES5.js b/tests/baselines/reference/computedPropertyNames30_ES5.js
index 9f4a4ab51f9..c2c7cddd971 100644
--- a/tests/baselines/reference/computedPropertyNames30_ES5.js
+++ b/tests/baselines/reference/computedPropertyNames30_ES5.js
@@ -29,8 +29,7 @@ var Base = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         (function () {
             var obj = (_a = {},
                 // Ideally, we would capture this. But the reference is
diff --git a/tests/baselines/reference/constructorArgs.js b/tests/baselines/reference/constructorArgs.js
index c7939472a96..6bbea0fddf7 100644
--- a/tests/baselines/reference/constructorArgs.js
+++ b/tests/baselines/reference/constructorArgs.js
@@ -29,8 +29,7 @@ var Super = (function () {
 var Sub = (function (_super) {
     __extends(Sub, _super);
     function Sub(options) {
-        var _this;
-        _this = _super.call(this, options.value) || this;
+        var _this = _super.call(this, options.value) || this;
         _this.options = options;
         return _this;
     }
diff --git a/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType2.js b/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType2.js
index 4f70c7d7f35..1ae239430c7 100644
--- a/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType2.js
+++ b/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType2.js
@@ -47,8 +47,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived(x) {
-        var _this;
-        _this = _super.call(this, x) || this;
+        var _this = _super.call(this, x) || this;
         return _this;
     }
     return Derived;
@@ -57,8 +56,7 @@ var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     // ok, not enforcing assignability relation on this
     function Derived2(x) {
-        var _this;
-        _this = _super.call(this, x) || this;
+        var _this = _super.call(this, x) || this;
         return 1;
         return _this;
     }
diff --git a/tests/baselines/reference/constructorOverloads2.js b/tests/baselines/reference/constructorOverloads2.js
index 0041acb489e..c26d031656f 100644
--- a/tests/baselines/reference/constructorOverloads2.js
+++ b/tests/baselines/reference/constructorOverloads2.js
@@ -40,8 +40,7 @@ var FooBase = (function () {
 var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo(x, y) {
-        var _this;
-        _this = _super.call(this, x) || this;
+        var _this = _super.call(this, x) || this;
         return _this;
     }
     Foo.prototype.bar1 = function () { };
diff --git a/tests/baselines/reference/declFileGenericType2.js b/tests/baselines/reference/declFileGenericType2.js
index 0e5351e69ea..328ab0cd949 100644
--- a/tests/baselines/reference/declFileGenericType2.js
+++ b/tests/baselines/reference/declFileGenericType2.js
@@ -58,8 +58,7 @@ var templa;
             var AbstractElementController = (function (_super) {
                 __extends(AbstractElementController, _super);
                 function AbstractElementController() {
-                    var _this;
-                    _this = _super.call(this) || this;
+                    var _this = _super.call(this) || this;
                     return _this;
                 }
                 return AbstractElementController;
@@ -80,8 +79,7 @@ var templa;
                 var AbstractCompositeElementController = (function (_super) {
                     __extends(AbstractCompositeElementController, _super);
                     function AbstractCompositeElementController() {
-                        var _this;
-                        _this = _super.call(this) || this;
+                        var _this = _super.call(this) || this;
                         _this._controllers = [];
                         return _this;
                     }
diff --git a/tests/baselines/reference/decoratorOnClassConstructor2.js b/tests/baselines/reference/decoratorOnClassConstructor2.js
index 1f0b9b0d517..44bde0a171d 100644
--- a/tests/baselines/reference/decoratorOnClassConstructor2.js
+++ b/tests/baselines/reference/decoratorOnClassConstructor2.js
@@ -45,8 +45,7 @@ var _0_ts_2 = require("./0.ts");
 var C = (function (_super) {
     __extends(C, _super);
     function C(prop) {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         return _this;
     }
     return C;
diff --git a/tests/baselines/reference/decoratorOnClassConstructor3.js b/tests/baselines/reference/decoratorOnClassConstructor3.js
index 9182cce66f4..5130986b1f7 100644
--- a/tests/baselines/reference/decoratorOnClassConstructor3.js
+++ b/tests/baselines/reference/decoratorOnClassConstructor3.js
@@ -48,8 +48,7 @@ var _0_2 = require("./0");
 var C = (function (_super) {
     __extends(C, _super);
     function C(prop) {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         return _this;
     }
     return C;
diff --git a/tests/baselines/reference/derivedClassOverridesPrivateFunction1.js b/tests/baselines/reference/derivedClassOverridesPrivateFunction1.js
index fd601ff2211..a0b1559d430 100644
--- a/tests/baselines/reference/derivedClassOverridesPrivateFunction1.js
+++ b/tests/baselines/reference/derivedClassOverridesPrivateFunction1.js
@@ -32,8 +32,7 @@ var BaseClass = (function () {
 var DerivedClass = (function (_super) {
     __extends(DerivedClass, _super);
     function DerivedClass() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         return _this;
     }
     DerivedClass.prototype._init = function () {
diff --git a/tests/baselines/reference/derivedClassOverridesProtectedMembers.js b/tests/baselines/reference/derivedClassOverridesProtectedMembers.js
index 12344c19915..e86806d31d2 100644
--- a/tests/baselines/reference/derivedClassOverridesProtectedMembers.js
+++ b/tests/baselines/reference/derivedClassOverridesProtectedMembers.js
@@ -66,8 +66,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived(a) {
-        var _this;
-        _this = _super.call(this, x) || this;
+        var _this = _super.call(this, x) || this;
         return _this;
     }
     Derived.prototype.b = function (a) { };
diff --git a/tests/baselines/reference/derivedClassOverridesProtectedMembers2.js b/tests/baselines/reference/derivedClassOverridesProtectedMembers2.js
index 37be9e209ac..3035b2cb56f 100644
--- a/tests/baselines/reference/derivedClassOverridesProtectedMembers2.js
+++ b/tests/baselines/reference/derivedClassOverridesProtectedMembers2.js
@@ -94,8 +94,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived(a) {
-        var _this;
-        _this = _super.call(this, a) || this;
+        var _this = _super.call(this, a) || this;
         return _this;
     }
     Derived.prototype.b = function (a) { };
diff --git a/tests/baselines/reference/derivedClassOverridesProtectedMembers3.js b/tests/baselines/reference/derivedClassOverridesProtectedMembers3.js
index 0836c9d7f41..0e0c1c1ff01 100644
--- a/tests/baselines/reference/derivedClassOverridesProtectedMembers3.js
+++ b/tests/baselines/reference/derivedClassOverridesProtectedMembers3.js
@@ -103,8 +103,7 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1(a) {
-        var _this;
-        _this = _super.call(this, a) || this;
+        var _this = _super.call(this, a) || this;
         return _this;
     }
     return Derived1;
@@ -112,8 +111,7 @@ var Derived1 = (function (_super) {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2(a) {
-        var _this;
-        _this = _super.call(this, a) || this;
+        var _this = _super.call(this, a) || this;
         return _this;
     }
     Derived2.prototype.b = function (a) { };
@@ -122,8 +120,7 @@ var Derived2 = (function (_super) {
 var Derived3 = (function (_super) {
     __extends(Derived3, _super);
     function Derived3(a) {
-        var _this;
-        _this = _super.call(this, a) || this;
+        var _this = _super.call(this, a) || this;
         return _this;
     }
     Object.defineProperty(Derived3.prototype, "c", {
@@ -136,8 +133,7 @@ var Derived3 = (function (_super) {
 var Derived4 = (function (_super) {
     __extends(Derived4, _super);
     function Derived4(a) {
-        var _this;
-        _this = _super.call(this, a) || this;
+        var _this = _super.call(this, a) || this;
         return _this;
     }
     Object.defineProperty(Derived4.prototype, "c", {
@@ -150,8 +146,7 @@ var Derived4 = (function (_super) {
 var Derived5 = (function (_super) {
     __extends(Derived5, _super);
     function Derived5(a) {
-        var _this;
-        _this = _super.call(this, a) || this;
+        var _this = _super.call(this, a) || this;
         return _this;
     }
     return Derived5;
@@ -159,8 +154,7 @@ var Derived5 = (function (_super) {
 var Derived6 = (function (_super) {
     __extends(Derived6, _super);
     function Derived6(a) {
-        var _this;
-        _this = _super.call(this, a) || this;
+        var _this = _super.call(this, a) || this;
         return _this;
     }
     return Derived6;
@@ -168,8 +162,7 @@ var Derived6 = (function (_super) {
 var Derived7 = (function (_super) {
     __extends(Derived7, _super);
     function Derived7(a) {
-        var _this;
-        _this = _super.call(this, a) || this;
+        var _this = _super.call(this, a) || this;
         return _this;
     }
     Derived7.s = function (a) { };
@@ -178,8 +171,7 @@ var Derived7 = (function (_super) {
 var Derived8 = (function (_super) {
     __extends(Derived8, _super);
     function Derived8(a) {
-        var _this;
-        _this = _super.call(this, a) || this;
+        var _this = _super.call(this, a) || this;
         return _this;
     }
     Object.defineProperty(Derived8, "t", {
@@ -192,8 +184,7 @@ var Derived8 = (function (_super) {
 var Derived9 = (function (_super) {
     __extends(Derived9, _super);
     function Derived9(a) {
-        var _this;
-        _this = _super.call(this, a) || this;
+        var _this = _super.call(this, a) || this;
         return _this;
     }
     Object.defineProperty(Derived9, "t", {
@@ -206,8 +197,7 @@ var Derived9 = (function (_super) {
 var Derived10 = (function (_super) {
     __extends(Derived10, _super);
     function Derived10(a) {
-        var _this;
-        _this = _super.call(this, a) || this;
+        var _this = _super.call(this, a) || this;
         return _this;
     }
     return Derived10;
diff --git a/tests/baselines/reference/derivedClassOverridesPublicMembers.js b/tests/baselines/reference/derivedClassOverridesPublicMembers.js
index 8d0375ab13a..703f1d4a833 100644
--- a/tests/baselines/reference/derivedClassOverridesPublicMembers.js
+++ b/tests/baselines/reference/derivedClassOverridesPublicMembers.js
@@ -92,8 +92,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived(a) {
-        var _this;
-        _this = _super.call(this, x) || this;
+        var _this = _super.call(this, x) || this;
         return _this;
     }
     Derived.prototype.b = function (a) { };
diff --git a/tests/baselines/reference/derivedClassParameterProperties.js b/tests/baselines/reference/derivedClassParameterProperties.js
index f623653d6fa..27dcc4b7d5d 100644
--- a/tests/baselines/reference/derivedClassParameterProperties.js
+++ b/tests/baselines/reference/derivedClassParameterProperties.js
@@ -130,8 +130,7 @@ var Derived2 = (function (_super) {
 var Derived3 = (function (_super) {
     __extends(Derived3, _super);
     function Derived3(y) {
-        var _this;
-        _this = _super.call(this) || this; // ok
+        var _this = _super.call(this) || this;
         _this.y = y;
         var a = 1;
         return _this;
@@ -152,8 +151,7 @@ var Derived4 = (function (_super) {
 var Derived5 = (function (_super) {
     __extends(Derived5, _super);
     function Derived5(y) {
-        var _this;
-        _this = _super.call(this) || this; // ok
+        var _this = _super.call(this) || this;
         _this.a = 1;
         var b = 2;
         return _this;
@@ -186,8 +184,7 @@ var Derived7 = (function (_super) {
 var Derived8 = (function (_super) {
     __extends(Derived8, _super);
     function Derived8(y) {
-        var _this;
-        _this = _super.call(this) || this; // ok
+        var _this = _super.call(this) || this;
         _this.a = 1;
         _this.a = 3;
         _this.b = 3;
@@ -216,8 +213,7 @@ var Derived9 = (function (_super) {
 var Derived10 = (function (_super) {
     __extends(Derived10, _super);
     function Derived10(y) {
-        var _this;
-        _this = _super.call(this) || this; // ok
+        var _this = _super.call(this) || this;
         _this.a = 1;
         _this.a = 3;
         _this.b = 3;
diff --git a/tests/baselines/reference/derivedClassSuperCallsInNonConstructorMembers.js b/tests/baselines/reference/derivedClassSuperCallsInNonConstructorMembers.js
index e3bbf2699c5..b778d7bbca2 100644
--- a/tests/baselines/reference/derivedClassSuperCallsInNonConstructorMembers.js
+++ b/tests/baselines/reference/derivedClassSuperCallsInNonConstructorMembers.js
@@ -46,8 +46,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.a = _this = _super.call(this) || this;
         return _this;
     }
diff --git a/tests/baselines/reference/derivedClassSuperCallsWithThisArg.js b/tests/baselines/reference/derivedClassSuperCallsWithThisArg.js
index 102944889bd..039e25919f8 100644
--- a/tests/baselines/reference/derivedClassSuperCallsWithThisArg.js
+++ b/tests/baselines/reference/derivedClassSuperCallsWithThisArg.js
@@ -42,8 +42,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this;
-        _this = _super.call(this, _this) || this; // ok
+        var _this = _super.call(this, _this) || this;
         return _this;
     }
     return Derived;
@@ -51,8 +50,7 @@ var Derived = (function (_super) {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2(a) {
-        var _this;
-        _this = _super.call(this, _this) || this; // error
+        var _this = _super.call(this, _this) || this;
         _this.a = a;
         return _this;
     }
@@ -61,8 +59,7 @@ var Derived2 = (function (_super) {
 var Derived3 = (function (_super) {
     __extends(Derived3, _super);
     function Derived3(a) {
-        var _this;
-        _this = _super.call(this, function () { return _this; }) || this; // error
+        var _this = _super.call(this, function () { return _this; }) || this;
         _this.a = a;
         return _this;
     }
@@ -71,8 +68,7 @@ var Derived3 = (function (_super) {
 var Derived4 = (function (_super) {
     __extends(Derived4, _super);
     function Derived4(a) {
-        var _this;
-        _this = _super.call(this, function () { return this; }) || this; // ok
+        var _this = _super.call(this, function () { return this; }) || this;
         _this.a = a;
         return _this;
     }
diff --git a/tests/baselines/reference/derivedClassWithoutExplicitConstructor.js b/tests/baselines/reference/derivedClassWithoutExplicitConstructor.js
index f5eb3d22360..7a6a7ecbb63 100644
--- a/tests/baselines/reference/derivedClassWithoutExplicitConstructor.js
+++ b/tests/baselines/reference/derivedClassWithoutExplicitConstructor.js
@@ -41,8 +41,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.x = 1;
         _this.y = 'hello';
         return _this;
@@ -60,8 +59,7 @@ var Base2 = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.x = 2;
         _this.y = null;
         return _this;
diff --git a/tests/baselines/reference/derivedClassWithoutExplicitConstructor2.js b/tests/baselines/reference/derivedClassWithoutExplicitConstructor2.js
index 5ad20389230..62beb4bf28f 100644
--- a/tests/baselines/reference/derivedClassWithoutExplicitConstructor2.js
+++ b/tests/baselines/reference/derivedClassWithoutExplicitConstructor2.js
@@ -49,8 +49,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.x = 1;
         _this.y = 'hello';
         return _this;
@@ -70,8 +69,7 @@ var Base2 = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.x = 2;
         _this.y = null;
         return _this;
diff --git a/tests/baselines/reference/derivedClassWithoutExplicitConstructor3.js b/tests/baselines/reference/derivedClassWithoutExplicitConstructor3.js
index d0e5f22d4f3..c96d0c96723 100644
--- a/tests/baselines/reference/derivedClassWithoutExplicitConstructor3.js
+++ b/tests/baselines/reference/derivedClassWithoutExplicitConstructor3.js
@@ -63,8 +63,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived(y, z) {
-        var _this;
-        _this = _super.call(this, 2) || this;
+        var _this = _super.call(this, 2) || this;
         _this.b = '';
         _this.b = y;
         return _this;
@@ -74,8 +73,7 @@ var Derived = (function (_super) {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.x = 1;
         _this.y = 'hello';
         return _this;
@@ -94,8 +92,7 @@ var Base2 = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D(y, z) {
-        var _this;
-        _this = _super.call(this, 2) || this;
+        var _this = _super.call(this, 2) || this;
         _this.b = null;
         _this.b = y;
         return _this;
@@ -105,8 +102,7 @@ var D = (function (_super) {
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.x = 2;
         _this.y = null;
         return _this;
diff --git a/tests/baselines/reference/destructuringParameterDeclaration5.js b/tests/baselines/reference/destructuringParameterDeclaration5.js
index 8c35b9044a1..8781671853f 100644
--- a/tests/baselines/reference/destructuringParameterDeclaration5.js
+++ b/tests/baselines/reference/destructuringParameterDeclaration5.js
@@ -65,8 +65,7 @@ var Class = (function () {
 var SubClass = (function (_super) {
     __extends(SubClass, _super);
     function SubClass() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         return _this;
     }
     return SubClass;
@@ -79,8 +78,7 @@ var D = (function () {
 var SubD = (function (_super) {
     __extends(SubD, _super);
     function SubD() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         return _this;
     }
     return SubD;
diff --git a/tests/baselines/reference/emitSuperCallBeforeEmitParameterPropertyDeclaration1.js b/tests/baselines/reference/emitSuperCallBeforeEmitParameterPropertyDeclaration1.js
index efed8e66a15..05b061116d3 100644
--- a/tests/baselines/reference/emitSuperCallBeforeEmitParameterPropertyDeclaration1.js
+++ b/tests/baselines/reference/emitSuperCallBeforeEmitParameterPropertyDeclaration1.js
@@ -30,8 +30,7 @@ var B = (function (_super) {
     function B(x) {
         "use strict";
         'someStringForEgngInject';
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _this.x = x;
         return _this;
     }
diff --git a/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclaration1.js b/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclaration1.js
index 6e3d3bfaa1b..2cf2cb02073 100644
--- a/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclaration1.js
+++ b/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclaration1.js
@@ -32,8 +32,7 @@ var B = (function (_super) {
     function B() {
         "use strict";
         'someStringForEgngInject';
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _this.blub = 12;
         return _this;
     }
diff --git a/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclarationAndParameterPropertyDeclaration1.js b/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclarationAndParameterPropertyDeclaration1.js
index 6559569fe79..eaa52e39285 100644
--- a/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclarationAndParameterPropertyDeclaration1.js
+++ b/tests/baselines/reference/emitSuperCallBeforeEmitPropertyDeclarationAndParameterPropertyDeclaration1.js
@@ -30,8 +30,7 @@ var B = (function (_super) {
     function B(x) {
         "use strict";
         'someStringForEgngInject';
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _this.x = x;
         _this.blah = 2;
         return _this;
diff --git a/tests/baselines/reference/errorSuperCalls.js b/tests/baselines/reference/errorSuperCalls.js
index 864bc19a344..720894e50c0 100644
--- a/tests/baselines/reference/errorSuperCalls.js
+++ b/tests/baselines/reference/errorSuperCalls.js
@@ -147,8 +147,7 @@ var OtherBase = (function () {
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         //super call in class member initializer of derived type
         _this.t = _this = _super.call(this) || this;
         return _this;
diff --git a/tests/baselines/reference/errorSuperPropertyAccess.js b/tests/baselines/reference/errorSuperPropertyAccess.js
index 1b7c9a418fc..0fef86493f1 100644
--- a/tests/baselines/reference/errorSuperPropertyAccess.js
+++ b/tests/baselines/reference/errorSuperPropertyAccess.js
@@ -186,8 +186,7 @@ SomeBase.publicStaticMember = 0;
 var SomeDerived1 = (function (_super) {
     __extends(SomeDerived1, _super);
     function SomeDerived1() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _super.prototype.publicMember = 1;
         return _this;
     }
@@ -221,8 +220,7 @@ var SomeDerived1 = (function (_super) {
 var SomeDerived2 = (function (_super) {
     __extends(SomeDerived2, _super);
     function SomeDerived2() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _super.prototype.privateMember = 1;
         return _this;
     }
diff --git a/tests/baselines/reference/es6ClassTest.js b/tests/baselines/reference/es6ClassTest.js
index 705915812be..d0879152544 100644
--- a/tests/baselines/reference/es6ClassTest.js
+++ b/tests/baselines/reference/es6ClassTest.js
@@ -102,9 +102,8 @@ var Bar = (function () {
 var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo(x, y, z) {
-        var _this;
+        var _this = _super.call(this, x) || this;
         if (z === void 0) { z = 0; }
-        _this = _super.call(this, x) || this;
         _this.y = y;
         _this.z = z;
         _this.gar = 0;
diff --git a/tests/baselines/reference/es6ClassTest2.js b/tests/baselines/reference/es6ClassTest2.js
index eec5d830e01..9217f890377 100644
--- a/tests/baselines/reference/es6ClassTest2.js
+++ b/tests/baselines/reference/es6ClassTest2.js
@@ -267,8 +267,7 @@ var SuperParent = (function () {
 var SuperChild = (function (_super) {
     __extends(SuperChild, _super);
     function SuperChild() {
-        var _this;
-        _this = _super.call(this, 1) || this;
+        var _this = _super.call(this, 1) || this;
         return _this;
     }
     SuperChild.prototype.b = function () {
diff --git a/tests/baselines/reference/genericClassPropertyInheritanceSpecialization.js b/tests/baselines/reference/genericClassPropertyInheritanceSpecialization.js
index ccbac1d22b5..86410aaf10e 100644
--- a/tests/baselines/reference/genericClassPropertyInheritanceSpecialization.js
+++ b/tests/baselines/reference/genericClassPropertyInheritanceSpecialization.js
@@ -109,8 +109,7 @@ var PortalFx;
                 var Validator = (function (_super) {
                     __extends(Validator, _super);
                     function Validator(message) {
-                        var _this;
-                        _this = _super.call(this, message) || this;
+                        var _this = _super.call(this, message) || this;
                         return _this;
                     }
                     return Validator;
diff --git a/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes.js b/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes.js
index 246b9b76e3c..582937e7c0a 100644
--- a/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes.js
+++ b/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes.js
@@ -52,8 +52,7 @@ var EndGate;
         var NumberTween = (function (_super) {
             __extends(NumberTween, _super);
             function NumberTween(from) {
-                var _this;
-                _this = _super.call(this, from) || this;
+                var _this = _super.call(this, from) || this;
                 return _this;
             }
             return NumberTween;
diff --git a/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes2.js b/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes2.js
index e7744b28833..88173a4cbe3 100644
--- a/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes2.js
+++ b/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes2.js
@@ -51,8 +51,7 @@ var EndGate;
         var NumberTween = (function (_super) {
             __extends(NumberTween, _super);
             function NumberTween(from) {
-                var _this;
-                _this = _super.call(this, from) || this;
+                var _this = _super.call(this, from) || this;
                 return _this;
             }
             return NumberTween;
diff --git a/tests/baselines/reference/genericRecursiveImplicitConstructorErrors3.js b/tests/baselines/reference/genericRecursiveImplicitConstructorErrors3.js
index d22823b9f81..5a02ceb0ff4 100644
--- a/tests/baselines/reference/genericRecursiveImplicitConstructorErrors3.js
+++ b/tests/baselines/reference/genericRecursiveImplicitConstructorErrors3.js
@@ -59,8 +59,7 @@ var TypeScript;
     var PullTypeSymbol = (function (_super) {
         __extends(PullTypeSymbol, _super);
         function PullTypeSymbol() {
-            var _this;
-            _this = _super.apply(this, arguments) || this;
+            var _this = _super.apply(this, arguments) || this;
             _this._elementType = null;
             return _this;
         }
diff --git a/tests/baselines/reference/genericTypeConstraints.js b/tests/baselines/reference/genericTypeConstraints.js
index 48ff00e5ac2..b82e261a14f 100644
--- a/tests/baselines/reference/genericTypeConstraints.js
+++ b/tests/baselines/reference/genericTypeConstraints.js
@@ -38,8 +38,7 @@ var Bar = (function () {
 var BarExtended = (function (_super) {
     __extends(BarExtended, _super);
     function BarExtended() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         return _this;
     }
     return BarExtended;
diff --git a/tests/baselines/reference/interfaceExtendsClassWithPrivate2.js b/tests/baselines/reference/interfaceExtendsClassWithPrivate2.js
index 51c64f48f6c..49b5efbd012 100644
--- a/tests/baselines/reference/interfaceExtendsClassWithPrivate2.js
+++ b/tests/baselines/reference/interfaceExtendsClassWithPrivate2.js
@@ -39,8 +39,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.x = 2;
         _this.y = 3;
         return _this;
@@ -53,8 +52,7 @@ var D = (function (_super) {
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.x = "";
         return _this;
     }
diff --git a/tests/baselines/reference/lift.js b/tests/baselines/reference/lift.js
index a71f1c9065a..364d52d9385 100644
--- a/tests/baselines/reference/lift.js
+++ b/tests/baselines/reference/lift.js
@@ -32,8 +32,7 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C(y, z, w) {
-        var _this;
-        _this = _super.call(this, y) || this;
+        var _this = _super.call(this, y) || this;
         var x = 10 + w;
         var ll = x * w;
         return _this;
diff --git a/tests/baselines/reference/missingPropertiesOfClassExpression.js b/tests/baselines/reference/missingPropertiesOfClassExpression.js
index 20252f37e61..34b60940aa9 100644
--- a/tests/baselines/reference/missingPropertiesOfClassExpression.js
+++ b/tests/baselines/reference/missingPropertiesOfClassExpression.js
@@ -15,8 +15,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var George = (function (_super) {
     __extends(George, _super);
     function George() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         return _this;
     }
     return George;
diff --git a/tests/baselines/reference/objectCreationOfElementAccessExpression.js b/tests/baselines/reference/objectCreationOfElementAccessExpression.js
index 760454dd9a4..a1739ce0d8e 100644
--- a/tests/baselines/reference/objectCreationOfElementAccessExpression.js
+++ b/tests/baselines/reference/objectCreationOfElementAccessExpression.js
@@ -81,8 +81,7 @@ var Food = (function () {
 var MonsterFood = (function (_super) {
     __extends(MonsterFood, _super);
     function MonsterFood(name, flavor) {
-        var _this;
-        _this = _super.call(this, name) || this;
+        var _this = _super.call(this, name) || this;
         _this.flavor = flavor;
         return _this;
     }
@@ -91,8 +90,7 @@ var MonsterFood = (function (_super) {
 var IceCream = (function (_super) {
     __extends(IceCream, _super);
     function IceCream(flavor) {
-        var _this;
-        _this = _super.call(this, "Ice Cream", flavor) || this;
+        var _this = _super.call(this, "Ice Cream", flavor) || this;
         _this.flavor = flavor;
         return _this;
     }
@@ -101,8 +99,7 @@ var IceCream = (function (_super) {
 var Cookie = (function (_super) {
     __extends(Cookie, _super);
     function Cookie(flavor, isGlutenFree) {
-        var _this;
-        _this = _super.call(this, "Cookie", flavor) || this;
+        var _this = _super.call(this, "Cookie", flavor) || this;
         _this.flavor = flavor;
         _this.isGlutenFree = isGlutenFree;
         return _this;
@@ -112,8 +109,7 @@ var Cookie = (function (_super) {
 var PetFood = (function (_super) {
     __extends(PetFood, _super);
     function PetFood(name, whereToBuy) {
-        var _this;
-        _this = _super.call(this, name) || this;
+        var _this = _super.call(this, name) || this;
         _this.whereToBuy = whereToBuy;
         return _this;
     }
@@ -122,8 +118,7 @@ var PetFood = (function (_super) {
 var ExpensiveOrganicDogFood = (function (_super) {
     __extends(ExpensiveOrganicDogFood, _super);
     function ExpensiveOrganicDogFood(whereToBuy) {
-        var _this;
-        _this = _super.call(this, "Origen", whereToBuy) || this;
+        var _this = _super.call(this, "Origen", whereToBuy) || this;
         _this.whereToBuy = whereToBuy;
         return _this;
     }
@@ -132,8 +127,7 @@ var ExpensiveOrganicDogFood = (function (_super) {
 var ExpensiveOrganicCatFood = (function (_super) {
     __extends(ExpensiveOrganicCatFood, _super);
     function ExpensiveOrganicCatFood(whereToBuy, containsFish) {
-        var _this;
-        _this = _super.call(this, "Nature's Logic", whereToBuy) || this;
+        var _this = _super.call(this, "Nature's Logic", whereToBuy) || this;
         _this.whereToBuy = whereToBuy;
         _this.containsFish = containsFish;
         return _this;
diff --git a/tests/baselines/reference/optionalMethods.js b/tests/baselines/reference/optionalMethods.js
index 72df561227f..8b999b45d71 100644
--- a/tests/baselines/reference/optionalMethods.js
+++ b/tests/baselines/reference/optionalMethods.js
@@ -109,8 +109,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.a = 1;
         return _this;
     }
diff --git a/tests/baselines/reference/optionalParamArgsTest.js b/tests/baselines/reference/optionalParamArgsTest.js
index 258f05cbc85..e93058d71d2 100644
--- a/tests/baselines/reference/optionalParamArgsTest.js
+++ b/tests/baselines/reference/optionalParamArgsTest.js
@@ -161,9 +161,8 @@ var C1 = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2(v2) {
-        var _this;
+        var _this = _super.call(this, v2) || this;
         if (v2 === void 0) { v2 = 6; }
-        _this = _super.call(this, v2) || this;
         return _this;
     }
     return C2;
diff --git a/tests/baselines/reference/optionalParameterProperty.js b/tests/baselines/reference/optionalParameterProperty.js
index ca78ad7286e..f9b9ecaf990 100644
--- a/tests/baselines/reference/optionalParameterProperty.js
+++ b/tests/baselines/reference/optionalParameterProperty.js
@@ -25,8 +25,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D(p) {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _this.p = p;
         return _this;
     }
diff --git a/tests/baselines/reference/overloadOnConstConstraintChecks4.js b/tests/baselines/reference/overloadOnConstConstraintChecks4.js
index 360b38ce70c..49d96b97b74 100644
--- a/tests/baselines/reference/overloadOnConstConstraintChecks4.js
+++ b/tests/baselines/reference/overloadOnConstConstraintChecks4.js
@@ -27,8 +27,7 @@ var Z = (function () {
 var A = (function (_super) {
     __extends(A, _super);
     function A() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.x = 1;
         return _this;
     }
diff --git a/tests/baselines/reference/parserAstSpans1.js b/tests/baselines/reference/parserAstSpans1.js
index 799a17d47de..c7bdb90775e 100644
--- a/tests/baselines/reference/parserAstSpans1.js
+++ b/tests/baselines/reference/parserAstSpans1.js
@@ -318,8 +318,7 @@ var c2 = (function () {
 var c3 = (function (_super) {
     __extends(c3, _super);
     function c3() {
-        var _this;
-        _this = _super.call(this, 10) || this;
+        var _this = _super.call(this, 10) || this;
         _this.p1 = _super.prototype.c2_p1;
         return _this;
     }
@@ -407,8 +406,7 @@ var c5 = (function () {
 var c6 = (function (_super) {
     __extends(c6, _super);
     function c6() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _this.d = _super.prototype.b;
         return _this;
     }
diff --git a/tests/baselines/reference/parserRealSource10.js b/tests/baselines/reference/parserRealSource10.js
index 88516c9a692..253f856a990 100644
--- a/tests/baselines/reference/parserRealSource10.js
+++ b/tests/baselines/reference/parserRealSource10.js
@@ -826,8 +826,7 @@ var TypeScript;
     var NumberLiteralToken = (function (_super) {
         __extends(NumberLiteralToken, _super);
         function NumberLiteralToken(value, hasEmptyFraction) {
-            var _this;
-            _this = _super.call(this, TokenID.NumberLiteral) || this;
+            var _this = _super.call(this, TokenID.NumberLiteral) || this;
             _this.value = value;
             _this.hasEmptyFraction = hasEmptyFraction;
             return _this;
@@ -844,8 +843,7 @@ var TypeScript;
     var StringLiteralToken = (function (_super) {
         __extends(StringLiteralToken, _super);
         function StringLiteralToken(value) {
-            var _this;
-            _this = _super.call(this, TokenID.StringLiteral) || this;
+            var _this = _super.call(this, TokenID.StringLiteral) || this;
             _this.value = value;
             return _this;
         }
@@ -861,8 +859,7 @@ var TypeScript;
     var IdentifierToken = (function (_super) {
         __extends(IdentifierToken, _super);
         function IdentifierToken(value, hasEscapeSequence) {
-            var _this;
-            _this = _super.call(this, TokenID.Identifier) || this;
+            var _this = _super.call(this, TokenID.Identifier) || this;
             _this.value = value;
             _this.hasEscapeSequence = hasEscapeSequence;
             return _this;
@@ -879,8 +876,7 @@ var TypeScript;
     var WhitespaceToken = (function (_super) {
         __extends(WhitespaceToken, _super);
         function WhitespaceToken(tokenId, value) {
-            var _this;
-            _this = _super.call(this, tokenId) || this;
+            var _this = _super.call(this, tokenId) || this;
             _this.value = value;
             return _this;
         }
@@ -896,8 +892,7 @@ var TypeScript;
     var CommentToken = (function (_super) {
         __extends(CommentToken, _super);
         function CommentToken(tokenID, value, isBlock, startPos, line, endsLine) {
-            var _this;
-            _this = _super.call(this, tokenID) || this;
+            var _this = _super.call(this, tokenID) || this;
             _this.value = value;
             _this.isBlock = isBlock;
             _this.startPos = startPos;
@@ -917,8 +912,7 @@ var TypeScript;
     var RegularExpressionLiteralToken = (function (_super) {
         __extends(RegularExpressionLiteralToken, _super);
         function RegularExpressionLiteralToken(regex) {
-            var _this;
-            _this = _super.call(this, TokenID.RegularExpressionLiteral) || this;
+            var _this = _super.call(this, TokenID.RegularExpressionLiteral) || this;
             _this.regex = regex;
             return _this;
         }
diff --git a/tests/baselines/reference/parserRealSource11.js b/tests/baselines/reference/parserRealSource11.js
index fa112e51dad..fd2c017b637 100644
--- a/tests/baselines/reference/parserRealSource11.js
+++ b/tests/baselines/reference/parserRealSource11.js
@@ -2386,8 +2386,7 @@ var TypeScript;
     var AST = (function (_super) {
         __extends(AST, _super);
         function AST(nodeType) {
-            var _this;
-            _this = _super.call(this) || this;
+            var _this = _super.call(this) || this;
             _this.nodeType = nodeType;
             _this.type = null;
             _this.flags = ASTFlags.Writeable;
@@ -2544,8 +2543,7 @@ var TypeScript;
     var IncompleteAST = (function (_super) {
         __extends(IncompleteAST, _super);
         function IncompleteAST(min, lim) {
-            var _this;
-            _this = _super.call(this, NodeType.Error) || this;
+            var _this = _super.call(this, NodeType.Error) || this;
             _this.minChar = min;
             _this.limChar = lim;
             return _this;
@@ -2556,8 +2554,7 @@ var TypeScript;
     var ASTList = (function (_super) {
         __extends(ASTList, _super);
         function ASTList() {
-            var _this;
-            _this = _super.call(this, NodeType.List) || this;
+            var _this = _super.call(this, NodeType.List) || this;
             _this.enclosingScope = null;
             _this.members = new AST[];
             return _this;
@@ -2625,8 +2622,7 @@ var TypeScript;
         //    To change text, and to avoid running into a situation where 'actualText' does not 
         //    match 'text', always use setText.
         function Identifier(actualText, hasEscapeSequence) {
-            var _this;
-            _this = _super.call(this, NodeType.Name) || this;
+            var _this = _super.call(this, NodeType.Name) || this;
             _this.actualText = actualText;
             _this.hasEscapeSequence = hasEscapeSequence;
             _this.sym = null;
@@ -2671,8 +2667,7 @@ var TypeScript;
     var MissingIdentifier = (function (_super) {
         __extends(MissingIdentifier, _super);
         function MissingIdentifier() {
-            var _this;
-            _this = _super.call(this, "__missing") || this;
+            var _this = _super.call(this, "__missing") || this;
             return _this;
         }
         MissingIdentifier.prototype.isMissing = function () {
@@ -2687,8 +2682,7 @@ var TypeScript;
     var Label = (function (_super) {
         __extends(Label, _super);
         function Label(id) {
-            var _this;
-            _this = _super.call(this, NodeType.Label) || this;
+            var _this = _super.call(this, NodeType.Label) || this;
             _this.id = id;
             return _this;
         }
@@ -2713,8 +2707,7 @@ var TypeScript;
     var Expression = (function (_super) {
         __extends(Expression, _super);
         function Expression(nodeType) {
-            var _this;
-            _this = _super.call(this, nodeType) || this;
+            var _this = _super.call(this, nodeType) || this;
             return _this;
         }
         Expression.prototype.isExpression = function () { return true; };
@@ -2725,8 +2718,7 @@ var TypeScript;
     var UnaryExpression = (function (_super) {
         __extends(UnaryExpression, _super);
         function UnaryExpression(nodeType, operand) {
-            var _this;
-            _this = _super.call(this, nodeType) || this;
+            var _this = _super.call(this, nodeType) || this;
             _this.operand = operand;
             _this.targetType = null; // Target type for an object literal (null if no target type)
             _this.castTerm = null;
@@ -2871,8 +2863,7 @@ var TypeScript;
     var CallExpression = (function (_super) {
         __extends(CallExpression, _super);
         function CallExpression(nodeType, target, arguments) {
-            var _this;
-            _this = _super.call(this, nodeType) || this;
+            var _this = _super.call(this, nodeType) || this;
             _this.target = target;
             _this.arguments = arguments;
             _this.signature = null;
@@ -2905,8 +2896,7 @@ var TypeScript;
     var BinaryExpression = (function (_super) {
         __extends(BinaryExpression, _super);
         function BinaryExpression(nodeType, operand1, operand2) {
-            var _this;
-            _this = _super.call(this, nodeType) || this;
+            var _this = _super.call(this, nodeType) || this;
             _this.operand1 = operand1;
             _this.operand2 = operand2;
             return _this;
@@ -3059,8 +3049,7 @@ var TypeScript;
     var ConditionalExpression = (function (_super) {
         __extends(ConditionalExpression, _super);
         function ConditionalExpression(operand1, operand2, operand3) {
-            var _this;
-            _this = _super.call(this, NodeType.ConditionalExpression) || this;
+            var _this = _super.call(this, NodeType.ConditionalExpression) || this;
             _this.operand1 = operand1;
             _this.operand2 = operand2;
             _this.operand3 = operand3;
@@ -3086,8 +3075,7 @@ var TypeScript;
     var NumberLiteral = (function (_super) {
         __extends(NumberLiteral, _super);
         function NumberLiteral(value, hasEmptyFraction) {
-            var _this;
-            _this = _super.call(this, NodeType.NumberLit) || this;
+            var _this = _super.call(this, NodeType.NumberLit) || this;
             _this.value = value;
             _this.hasEmptyFraction = hasEmptyFraction;
             _this.isNegativeZero = false;
@@ -3129,8 +3117,7 @@ var TypeScript;
     var RegexLiteral = (function (_super) {
         __extends(RegexLiteral, _super);
         function RegexLiteral(regex) {
-            var _this;
-            _this = _super.call(this, NodeType.Regex) || this;
+            var _this = _super.call(this, NodeType.Regex) || this;
             _this.regex = regex;
             return _this;
         }
@@ -3151,8 +3138,7 @@ var TypeScript;
     var StringLiteral = (function (_super) {
         __extends(StringLiteral, _super);
         function StringLiteral(text) {
-            var _this;
-            _this = _super.call(this, NodeType.QString) || this;
+            var _this = _super.call(this, NodeType.QString) || this;
             _this.text = text;
             return _this;
         }
@@ -3179,8 +3165,7 @@ var TypeScript;
     var ModuleElement = (function (_super) {
         __extends(ModuleElement, _super);
         function ModuleElement(nodeType) {
-            var _this;
-            _this = _super.call(this, nodeType) || this;
+            var _this = _super.call(this, nodeType) || this;
             return _this;
         }
         return ModuleElement;
@@ -3189,8 +3174,7 @@ var TypeScript;
     var ImportDeclaration = (function (_super) {
         __extends(ImportDeclaration, _super);
         function ImportDeclaration(id, alias) {
-            var _this;
-            _this = _super.call(this, NodeType.ImportDeclaration) || this;
+            var _this = _super.call(this, NodeType.ImportDeclaration) || this;
             _this.id = id;
             _this.alias = alias;
             _this.varFlags = VarFlags.None;
@@ -3250,8 +3234,7 @@ var TypeScript;
     var BoundDecl = (function (_super) {
         __extends(BoundDecl, _super);
         function BoundDecl(id, nodeType, nestingLevel) {
-            var _this;
-            _this = _super.call(this, nodeType) || this;
+            var _this = _super.call(this, nodeType) || this;
             _this.id = id;
             _this.nestingLevel = nestingLevel;
             _this.init = null;
@@ -3276,8 +3259,7 @@ var TypeScript;
     var VarDecl = (function (_super) {
         __extends(VarDecl, _super);
         function VarDecl(id, nest) {
-            var _this;
-            _this = _super.call(this, id, NodeType.VarDecl, nest) || this;
+            var _this = _super.call(this, id, NodeType.VarDecl, nest) || this;
             return _this;
         }
         VarDecl.prototype.isAmbient = function () { return hasFlag(this.varFlags, VarFlags.Ambient); };
@@ -3295,8 +3277,7 @@ var TypeScript;
     var ArgDecl = (function (_super) {
         __extends(ArgDecl, _super);
         function ArgDecl(id) {
-            var _this;
-            _this = _super.call(this, id, NodeType.ArgDecl, 0) || this;
+            var _this = _super.call(this, id, NodeType.ArgDecl, 0) || this;
             _this.isOptional = false;
             _this.parameterPropertySym = null;
             return _this;
@@ -3319,8 +3300,7 @@ var TypeScript;
     var FuncDecl = (function (_super) {
         __extends(FuncDecl, _super);
         function FuncDecl(name, bod, isConstructor, arguments, vars, scopes, statics, nodeType) {
-            var _this;
-            _this = _super.call(this, nodeType) || this;
+            var _this = _super.call(this, nodeType) || this;
             _this.name = name;
             _this.bod = bod;
             _this.isConstructor = isConstructor;
@@ -3461,8 +3441,7 @@ var TypeScript;
     var Script = (function (_super) {
         __extends(Script, _super);
         function Script(vars, scopes) {
-            var _this;
-            _this = _super.call(this, new Identifier("script"), null, false, null, vars, scopes, null, NodeType.Script) || this;
+            var _this = _super.call(this, new Identifier("script"), null, false, null, vars, scopes, null, NodeType.Script) || this;
             _this.locationInfo = null;
             _this.referencedFiles = [];
             _this.requiresGlobal = false;
@@ -3532,8 +3511,7 @@ var TypeScript;
     var NamedDeclaration = (function (_super) {
         __extends(NamedDeclaration, _super);
         function NamedDeclaration(nodeType, name, members) {
-            var _this;
-            _this = _super.call(this, nodeType) || this;
+            var _this = _super.call(this, nodeType) || this;
             _this.name = name;
             _this.members = members;
             _this.leftCurlyCount = 0;
@@ -3546,8 +3524,7 @@ var TypeScript;
     var ModuleDeclaration = (function (_super) {
         __extends(ModuleDeclaration, _super);
         function ModuleDeclaration(name, members, vars, scopes, endingToken) {
-            var _this;
-            _this = _super.call(this, NodeType.ModuleDeclaration, name, members) || this;
+            var _this = _super.call(this, NodeType.ModuleDeclaration, name, members) || this;
             _this.endingToken = endingToken;
             _this.modFlags = ModuleFlags.ShouldEmitModuleDecl;
             _this.amdDependencies = [];
@@ -3583,8 +3560,7 @@ var TypeScript;
     var TypeDeclaration = (function (_super) {
         __extends(TypeDeclaration, _super);
         function TypeDeclaration(nodeType, name, extendsList, implementsList, members) {
-            var _this;
-            _this = _super.call(this, nodeType, name, members) || this;
+            var _this = _super.call(this, nodeType, name, members) || this;
             _this.extendsList = extendsList;
             _this.implementsList = implementsList;
             _this.varFlags = VarFlags.None;
@@ -3602,8 +3578,7 @@ var TypeScript;
     var ClassDeclaration = (function (_super) {
         __extends(ClassDeclaration, _super);
         function ClassDeclaration(name, members, extendsList, implementsList) {
-            var _this;
-            _this = _super.call(this, NodeType.ClassDeclaration, name, extendsList, implementsList, members) || this;
+            var _this = _super.call(this, NodeType.ClassDeclaration, name, extendsList, implementsList, members) || this;
             _this.knownMemberNames = {};
             _this.constructorDecl = null;
             _this.constructorNestingLevel = 0;
@@ -3622,8 +3597,7 @@ var TypeScript;
     var InterfaceDeclaration = (function (_super) {
         __extends(InterfaceDeclaration, _super);
         function InterfaceDeclaration(name, members, extendsList, implementsList) {
-            var _this;
-            _this = _super.call(this, NodeType.InterfaceDeclaration, name, extendsList, implementsList, members) || this;
+            var _this = _super.call(this, NodeType.InterfaceDeclaration, name, extendsList, implementsList, members) || this;
             return _this;
         }
         InterfaceDeclaration.prototype.typeCheck = function (typeFlow) {
@@ -3637,8 +3611,7 @@ var TypeScript;
     var Statement = (function (_super) {
         __extends(Statement, _super);
         function Statement(nodeType) {
-            var _this;
-            _this = _super.call(this, nodeType) || this;
+            var _this = _super.call(this, nodeType) || this;
             _this.flags |= ASTFlags.IsStatement;
             return _this;
         }
@@ -3655,8 +3628,7 @@ var TypeScript;
     var LabeledStatement = (function (_super) {
         __extends(LabeledStatement, _super);
         function LabeledStatement(labels, stmt) {
-            var _this;
-            _this = _super.call(this, NodeType.LabeledStatement) || this;
+            var _this = _super.call(this, NodeType.LabeledStatement) || this;
             _this.labels = labels;
             _this.stmt = stmt;
             return _this;
@@ -3691,8 +3663,7 @@ var TypeScript;
     var Block = (function (_super) {
         __extends(Block, _super);
         function Block(statements, isStatementBlock) {
-            var _this;
-            _this = _super.call(this, NodeType.Block) || this;
+            var _this = _super.call(this, NodeType.Block) || this;
             _this.statements = statements;
             _this.isStatementBlock = isStatementBlock;
             return _this;
@@ -3748,8 +3719,7 @@ var TypeScript;
     var Jump = (function (_super) {
         __extends(Jump, _super);
         function Jump(nodeType) {
-            var _this;
-            _this = _super.call(this, nodeType) || this;
+            var _this = _super.call(this, nodeType) || this;
             _this.target = null;
             _this.resolvedTarget = null;
             return _this;
@@ -3801,8 +3771,7 @@ var TypeScript;
     var WhileStatement = (function (_super) {
         __extends(WhileStatement, _super);
         function WhileStatement(cond) {
-            var _this;
-            _this = _super.call(this, NodeType.While) || this;
+            var _this = _super.call(this, NodeType.While) || this;
             _this.cond = cond;
             _this.body = null;
             return _this;
@@ -3855,8 +3824,7 @@ var TypeScript;
     var DoWhileStatement = (function (_super) {
         __extends(DoWhileStatement, _super);
         function DoWhileStatement() {
-            var _this;
-            _this = _super.call(this, NodeType.DoWhile) || this;
+            var _this = _super.call(this, NodeType.DoWhile) || this;
             _this.body = null;
             _this.whileAST = null;
             _this.cond = null;
@@ -3913,8 +3881,7 @@ var TypeScript;
     var IfStatement = (function (_super) {
         __extends(IfStatement, _super);
         function IfStatement(cond) {
-            var _this;
-            _this = _super.call(this, NodeType.If) || this;
+            var _this = _super.call(this, NodeType.If) || this;
             _this.cond = cond;
             _this.elseBod = null;
             _this.statement = new ASTSpan();
@@ -3993,8 +3960,7 @@ var TypeScript;
     var ReturnStatement = (function (_super) {
         __extends(ReturnStatement, _super);
         function ReturnStatement() {
-            var _this;
-            _this = _super.call(this, NodeType.Return) || this;
+            var _this = _super.call(this, NodeType.Return) || this;
             _this.returnExpression = null;
             return _this;
         }
@@ -4026,8 +3992,7 @@ var TypeScript;
     var EndCode = (function (_super) {
         __extends(EndCode, _super);
         function EndCode() {
-            var _this;
-            _this = _super.call(this, NodeType.EndCode) || this;
+            var _this = _super.call(this, NodeType.EndCode) || this;
             return _this;
         }
         return EndCode;
@@ -4036,8 +4001,7 @@ var TypeScript;
     var ForInStatement = (function (_super) {
         __extends(ForInStatement, _super);
         function ForInStatement(lval, obj) {
-            var _this;
-            _this = _super.call(this, NodeType.ForIn) || this;
+            var _this = _super.call(this, NodeType.ForIn) || this;
             _this.lval = lval;
             _this.obj = obj;
             _this.statement = new ASTSpan();
@@ -4153,8 +4117,7 @@ var TypeScript;
     var ForStatement = (function (_super) {
         __extends(ForStatement, _super);
         function ForStatement(init) {
-            var _this;
-            _this = _super.call(this, NodeType.For) || this;
+            var _this = _super.call(this, NodeType.For) || this;
             _this.init = init;
             return _this;
         }
@@ -4246,8 +4209,7 @@ var TypeScript;
     var WithStatement = (function (_super) {
         __extends(WithStatement, _super);
         function WithStatement(expr) {
-            var _this;
-            _this = _super.call(this, NodeType.With) || this;
+            var _this = _super.call(this, NodeType.With) || this;
             _this.expr = expr;
             _this.withSym = null;
             return _this;
@@ -4274,8 +4236,7 @@ var TypeScript;
     var SwitchStatement = (function (_super) {
         __extends(SwitchStatement, _super);
         function SwitchStatement(val) {
-            var _this;
-            _this = _super.call(this, NodeType.Switch) || this;
+            var _this = _super.call(this, NodeType.Switch) || this;
             _this.val = val;
             _this.defaultCase = null;
             _this.statement = new ASTSpan();
@@ -4348,8 +4309,7 @@ var TypeScript;
     var CaseStatement = (function (_super) {
         __extends(CaseStatement, _super);
         function CaseStatement() {
-            var _this;
-            _this = _super.call(this, NodeType.Case) || this;
+            var _this = _super.call(this, NodeType.Case) || this;
             _this.expr = null;
             return _this;
         }
@@ -4403,8 +4363,7 @@ var TypeScript;
     var TypeReference = (function (_super) {
         __extends(TypeReference, _super);
         function TypeReference(term, arrayCount) {
-            var _this;
-            _this = _super.call(this, NodeType.TypeRef) || this;
+            var _this = _super.call(this, NodeType.TypeRef) || this;
             _this.term = term;
             _this.arrayCount = arrayCount;
             return _this;
@@ -4435,8 +4394,7 @@ var TypeScript;
     var TryFinally = (function (_super) {
         __extends(TryFinally, _super);
         function TryFinally(tryNode, finallyNode) {
-            var _this;
-            _this = _super.call(this, NodeType.TryFinally) || this;
+            var _this = _super.call(this, NodeType.TryFinally) || this;
             _this.tryNode = tryNode;
             _this.finallyNode = finallyNode;
             return _this;
@@ -4482,8 +4440,7 @@ var TypeScript;
     var TryCatch = (function (_super) {
         __extends(TryCatch, _super);
         function TryCatch(tryNode, catchNode) {
-            var _this;
-            _this = _super.call(this, NodeType.TryCatch) || this;
+            var _this = _super.call(this, NodeType.TryCatch) || this;
             _this.tryNode = tryNode;
             _this.catchNode = catchNode;
             return _this;
@@ -4534,8 +4491,7 @@ var TypeScript;
     var Try = (function (_super) {
         __extends(Try, _super);
         function Try(body) {
-            var _this;
-            _this = _super.call(this, NodeType.Try) || this;
+            var _this = _super.call(this, NodeType.Try) || this;
             _this.body = body;
             return _this;
         }
@@ -4564,8 +4520,7 @@ var TypeScript;
     var Catch = (function (_super) {
         __extends(Catch, _super);
         function Catch(param, body) {
-            var _this;
-            _this = _super.call(this, NodeType.Catch) || this;
+            var _this = _super.call(this, NodeType.Catch) || this;
             _this.param = param;
             _this.body = body;
             _this.statement = new ASTSpan();
@@ -4639,8 +4594,7 @@ var TypeScript;
     var Finally = (function (_super) {
         __extends(Finally, _super);
         function Finally(body) {
-            var _this;
-            _this = _super.call(this, NodeType.Finally) || this;
+            var _this = _super.call(this, NodeType.Finally) || this;
             _this.body = body;
             return _this;
         }
@@ -4669,8 +4623,7 @@ var TypeScript;
     var Comment = (function (_super) {
         __extends(Comment, _super);
         function Comment(content, isBlockComment, endsLine) {
-            var _this;
-            _this = _super.call(this, NodeType.Comment) || this;
+            var _this = _super.call(this, NodeType.Comment) || this;
             _this.content = content;
             _this.isBlockComment = isBlockComment;
             _this.endsLine = endsLine;
@@ -4697,8 +4650,7 @@ var TypeScript;
     var DebuggerStatement = (function (_super) {
         __extends(DebuggerStatement, _super);
         function DebuggerStatement() {
-            var _this;
-            _this = _super.call(this, NodeType.Debugger) || this;
+            var _this = _super.call(this, NodeType.Debugger) || this;
             return _this;
         }
         DebuggerStatement.prototype.emit = function (emitter, tokenId, startLine) {
diff --git a/tests/baselines/reference/parserharness.js b/tests/baselines/reference/parserharness.js
index 2d219c63e6a..059ac2efd8e 100644
--- a/tests/baselines/reference/parserharness.js
+++ b/tests/baselines/reference/parserharness.js
@@ -2380,8 +2380,7 @@ var Harness;
     var TestCase = (function (_super) {
         __extends(TestCase, _super);
         function TestCase(description, block) {
-            var _this;
-            _this = _super.call(this, description, block) || this;
+            var _this = _super.call(this, description, block) || this;
             _this.description = description;
             _this.block = block;
             return _this;
@@ -2416,8 +2415,7 @@ var Harness;
     var Scenario = (function (_super) {
         __extends(Scenario, _super);
         function Scenario(description, block) {
-            var _this;
-            _this = _super.call(this, description, block) || this;
+            var _this = _super.call(this, description, block) || this;
             _this.description = description;
             _this.block = block;
             return _this;
@@ -2473,8 +2471,7 @@ var Harness;
     var Run = (function (_super) {
         __extends(Run, _super);
         function Run() {
-            var _this;
-            _this = _super.call(this, 'Test Run', null) || this;
+            var _this = _super.call(this, 'Test Run', null) || this;
             return _this;
         }
         Run.prototype.run = function () {
diff --git a/tests/baselines/reference/privateInstanceMemberAccessibility.js b/tests/baselines/reference/privateInstanceMemberAccessibility.js
index c07238dff5e..6fa05178f91 100644
--- a/tests/baselines/reference/privateInstanceMemberAccessibility.js
+++ b/tests/baselines/reference/privateInstanceMemberAccessibility.js
@@ -27,8 +27,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.x = _super.prototype.foo; // error
         _this.z = _super.prototype.foo; // error
         return _this;
diff --git a/tests/baselines/reference/privateStaticMemberAccessibility.js b/tests/baselines/reference/privateStaticMemberAccessibility.js
index 0d4cfefb63b..c1897e8503a 100644
--- a/tests/baselines/reference/privateStaticMemberAccessibility.js
+++ b/tests/baselines/reference/privateStaticMemberAccessibility.js
@@ -22,8 +22,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.bing = function () { return Base.foo; }; // error
         return _this;
     }
diff --git a/tests/baselines/reference/readonlyConstructorAssignment.js b/tests/baselines/reference/readonlyConstructorAssignment.js
index 581b110298a..872c00486c0 100644
--- a/tests/baselines/reference/readonlyConstructorAssignment.js
+++ b/tests/baselines/reference/readonlyConstructorAssignment.js
@@ -56,8 +56,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B(x) {
-        var _this;
-        _this = _super.call(this, x) || this;
+        var _this = _super.call(this, x) || this;
         // Fails, x is readonly
         _this.x = 1;
         return _this;
@@ -69,8 +68,7 @@ var C = (function (_super) {
     // This is the usual behavior of readonly properties:
     // if one is redeclared in a base class, then it can be assigned to.
     function C(x) {
-        var _this;
-        _this = _super.call(this, x) || this;
+        var _this = _super.call(this, x) || this;
         _this.x = x;
         _this.x = 1;
         return _this;
@@ -88,8 +86,7 @@ var D = (function () {
 var E = (function (_super) {
     __extends(E, _super);
     function E(x) {
-        var _this;
-        _this = _super.call(this, x) || this;
+        var _this = _super.call(this, x) || this;
         _this.x = x;
         _this.x = 1;
         return _this;
diff --git a/tests/baselines/reference/returnInConstructor1.js b/tests/baselines/reference/returnInConstructor1.js
index 0ee301758cf..6c678db2358 100644
--- a/tests/baselines/reference/returnInConstructor1.js
+++ b/tests/baselines/reference/returnInConstructor1.js
@@ -123,8 +123,7 @@ var G = (function () {
 var H = (function (_super) {
     __extends(H, _super);
     function H() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         return new G(); //error
         return _this;
     }
@@ -133,8 +132,7 @@ var H = (function (_super) {
 var I = (function (_super) {
     __extends(I, _super);
     function I() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         return new G();
         return _this;
     }
diff --git a/tests/baselines/reference/scopeTests.js b/tests/baselines/reference/scopeTests.js
index 9436043094e..48863404a8e 100644
--- a/tests/baselines/reference/scopeTests.js
+++ b/tests/baselines/reference/scopeTests.js
@@ -25,8 +25,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _this.v = 1;
         _this.p = 1;
         C.s = 1;
diff --git a/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js b/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js
index 7fef0a42010..4bac0210c85 100644
--- a/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js
+++ b/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js
@@ -21,8 +21,7 @@ var AbstractGreeter = (function () {
 var Greeter = (function (_super) {
     __extends(Greeter, _super);
     function Greeter() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.a = 10;
         _this.nameA = "Ten";
         return _this;
diff --git a/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js.map b/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js.map
index 14f7f65f050..6b18a783dfa 100644
--- a/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js.map
+++ b/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js.map
@@ -1,2 +1,2 @@
 //// [sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js.map]
-{"version":3,"file":"sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js","sourceRoot":"","sources":["sourceMapValidationClassWithDefaultConstructorAndExtendsClause.ts"],"names":[],"mappings":";;;;;AAAA;IAAA;IACA,CAAC;IAAD,sBAAC;AAAD,CAAC,AADD,IACC;AAED;IAAsB,2BAAe;IAArC;QAAA,UAGC;;QAFU,OAAC,GAAG,EAAE,CAAC;QACP,WAAK,GAAG,KAAK,CAAC;;IACzB,CAAC;IAAD,cAAC;AAAD,CAAC,AAHD,CAAsB,eAAe,GAGpC"}
\ No newline at end of file
+{"version":3,"file":"sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js","sourceRoot":"","sources":["sourceMapValidationClassWithDefaultConstructorAndExtendsClause.ts"],"names":[],"mappings":";;;;;AAAA;IAAA;IACA,CAAC;IAAD,sBAAC;AAAD,CAAC,AADD,IACC;AAED;IAAsB,2BAAe;IAArC;QAAA,kDAGC;QAFU,OAAC,GAAG,EAAE,CAAC;QACP,WAAK,GAAG,KAAK,CAAC;;IACzB,CAAC;IAAD,cAAC;AAAD,CAAC,AAHD,CAAsB,eAAe,GAGpC"}
\ No newline at end of file
diff --git a/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.sourcemap.txt b/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.sourcemap.txt
index e1adf2f7a29..91e284fd063 100644
--- a/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.sourcemap.txt
+++ b/tests/baselines/reference/sourceMapValidationClassWithDefaultConstructorAndExtendsClause.sourcemap.txt
@@ -77,40 +77,38 @@ sourceFile:sourceMapValidationClassWithDefaultConstructorAndExtendsClause.ts
 ---
 >>>    function Greeter() {
 1 >^^^^
-2 >    ^^^^^^^^^^^^^^^->
+2 >    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
 1 >
 1 >Emitted(13, 5) Source(4, 1) + SourceIndex(0)
 ---
->>>        var _this;
+>>>        var _this = _super.apply(this, arguments) || this;
 1->^^^^^^^^
-2 >        ^^^^^^^^^^
-3 >                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
+2 >        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 1->
 2 >        class Greeter extends AbstractGreeter {
   >            public a = 10;
   >            public nameA = "Ten";
   >        }
 1->Emitted(14, 9) Source(4, 1) + SourceIndex(0)
-2 >Emitted(14, 19) Source(7, 2) + SourceIndex(0)
+2 >Emitted(14, 59) Source(7, 2) + SourceIndex(0)
 ---
->>>        _this = _super.apply(this, arguments) || this;
 >>>        _this.a = 10;
-1->^^^^^^^^
+1 >^^^^^^^^
 2 >        ^^^^^^^
 3 >               ^^^
 4 >                  ^^
 5 >                    ^
 6 >                     ^^^^^^^^->
-1->
+1 >
 2 >        a
 3 >                = 
 4 >                  10
 5 >                    ;
-1->Emitted(16, 9) Source(5, 12) + SourceIndex(0)
-2 >Emitted(16, 16) Source(5, 13) + SourceIndex(0)
-3 >Emitted(16, 19) Source(5, 16) + SourceIndex(0)
-4 >Emitted(16, 21) Source(5, 18) + SourceIndex(0)
-5 >Emitted(16, 22) Source(5, 19) + SourceIndex(0)
+1 >Emitted(15, 9) Source(5, 12) + SourceIndex(0)
+2 >Emitted(15, 16) Source(5, 13) + SourceIndex(0)
+3 >Emitted(15, 19) Source(5, 16) + SourceIndex(0)
+4 >Emitted(15, 21) Source(5, 18) + SourceIndex(0)
+5 >Emitted(15, 22) Source(5, 19) + SourceIndex(0)
 ---
 >>>        _this.nameA = "Ten";
 1->^^^^^^^^
@@ -124,11 +122,11 @@ sourceFile:sourceMapValidationClassWithDefaultConstructorAndExtendsClause.ts
 3 >                    = 
 4 >                      "Ten"
 5 >                           ;
-1->Emitted(17, 9) Source(6, 12) + SourceIndex(0)
-2 >Emitted(17, 20) Source(6, 17) + SourceIndex(0)
-3 >Emitted(17, 23) Source(6, 20) + SourceIndex(0)
-4 >Emitted(17, 28) Source(6, 25) + SourceIndex(0)
-5 >Emitted(17, 29) Source(6, 26) + SourceIndex(0)
+1->Emitted(16, 9) Source(6, 12) + SourceIndex(0)
+2 >Emitted(16, 20) Source(6, 17) + SourceIndex(0)
+3 >Emitted(16, 23) Source(6, 20) + SourceIndex(0)
+4 >Emitted(16, 28) Source(6, 25) + SourceIndex(0)
+5 >Emitted(16, 29) Source(6, 26) + SourceIndex(0)
 ---
 >>>        return _this;
 >>>    }
@@ -138,8 +136,8 @@ sourceFile:sourceMapValidationClassWithDefaultConstructorAndExtendsClause.ts
 1 >
   >
 2 >    }
-1 >Emitted(19, 5) Source(7, 1) + SourceIndex(0)
-2 >Emitted(19, 6) Source(7, 2) + SourceIndex(0)
+1 >Emitted(18, 5) Source(7, 1) + SourceIndex(0)
+2 >Emitted(18, 6) Source(7, 2) + SourceIndex(0)
 ---
 >>>    return Greeter;
 1->^^^^
@@ -147,8 +145,8 @@ sourceFile:sourceMapValidationClassWithDefaultConstructorAndExtendsClause.ts
 3 >                  ^^^->
 1->
 2 >    }
-1->Emitted(20, 5) Source(7, 1) + SourceIndex(0)
-2 >Emitted(20, 19) Source(7, 2) + SourceIndex(0)
+1->Emitted(19, 5) Source(7, 1) + SourceIndex(0)
+2 >Emitted(19, 19) Source(7, 2) + SourceIndex(0)
 ---
 >>>}(AbstractGreeter));
 1->
@@ -167,11 +165,11 @@ sourceFile:sourceMapValidationClassWithDefaultConstructorAndExtendsClause.ts
   >                     public a = 10;
   >                     public nameA = "Ten";
   >                 }
-1->Emitted(21, 1) Source(7, 1) + SourceIndex(0)
-2 >Emitted(21, 2) Source(7, 2) + SourceIndex(0)
-3 >Emitted(21, 2) Source(4, 1) + SourceIndex(0)
-4 >Emitted(21, 3) Source(4, 23) + SourceIndex(0)
-5 >Emitted(21, 18) Source(4, 38) + SourceIndex(0)
-6 >Emitted(21, 21) Source(7, 2) + SourceIndex(0)
+1->Emitted(20, 1) Source(7, 1) + SourceIndex(0)
+2 >Emitted(20, 2) Source(7, 2) + SourceIndex(0)
+3 >Emitted(20, 2) Source(4, 1) + SourceIndex(0)
+4 >Emitted(20, 3) Source(4, 23) + SourceIndex(0)
+5 >Emitted(20, 18) Source(4, 38) + SourceIndex(0)
+6 >Emitted(20, 21) Source(7, 2) + SourceIndex(0)
 ---
 >>>//# sourceMappingURL=sourceMapValidationClassWithDefaultConstructorAndExtendsClause.js.map
\ No newline at end of file
diff --git a/tests/baselines/reference/staticInheritance.js b/tests/baselines/reference/staticInheritance.js
index 5e769cab563..d204c1aed47 100644
--- a/tests/baselines/reference/staticInheritance.js
+++ b/tests/baselines/reference/staticInheritance.js
@@ -27,8 +27,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.p1 = doThing(A); // OK
         _this.p2 = doThing(B); // OK
         return _this;
diff --git a/tests/baselines/reference/strictModeInConstructor.js b/tests/baselines/reference/strictModeInConstructor.js
index 1c33f16a3c6..ecd6bacd20a 100644
--- a/tests/baselines/reference/strictModeInConstructor.js
+++ b/tests/baselines/reference/strictModeInConstructor.js
@@ -75,8 +75,7 @@ var B = (function (_super) {
     __extends(B, _super);
     function B() {
         "use strict"; // No error
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _this.s = 9;
         return _this;
     }
@@ -85,8 +84,7 @@ var B = (function (_super) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this;
-        _this = _super.call(this) || this; // No error
+        var _this = _super.call(this) || this;
         _this.s = 9;
         "use strict";
         return _this;
@@ -109,8 +107,7 @@ var Bs = (function (_super) {
     __extends(Bs, _super);
     function Bs() {
         "use strict"; // No error
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         return _this;
     }
     return Bs;
@@ -119,8 +116,7 @@ Bs.s = 9;
 var Cs = (function (_super) {
     __extends(Cs, _super);
     function Cs() {
-        var _this;
-        _this = _super.call(this) || this; // No error
+        var _this = _super.call(this) || this;
         "use strict";
         return _this;
     }
diff --git a/tests/baselines/reference/superAccess2.js b/tests/baselines/reference/superAccess2.js
index 408f9051bad..54c59978151 100644
--- a/tests/baselines/reference/superAccess2.js
+++ b/tests/baselines/reference/superAccess2.js
@@ -41,11 +41,10 @@ var Q = (function (_super) {
     __extends(Q, _super);
     // Super is not allowed in constructor args
     function Q(z, zz, zzz) {
-        var _this;
+        var _this = _super.call(this) || this;
         if (z === void 0) { z = _super.; }
         if (zz === void 0) { zz = _super.; }
         if (zzz === void 0) { zzz = function () { return _super.; }; }
-        _this = _super.call(this) || this;
         _this.z = z;
         _this.xx = _super.prototype.;
         return _this;
diff --git a/tests/baselines/reference/superCallArgsMustMatch.js b/tests/baselines/reference/superCallArgsMustMatch.js
index dc450147f88..106d7433bf5 100644
--- a/tests/baselines/reference/superCallArgsMustMatch.js
+++ b/tests/baselines/reference/superCallArgsMustMatch.js
@@ -40,10 +40,10 @@ var T5 = (function () {
 var T6 = (function (_super) {
     __extends(T6, _super);
     function T6() {
-        var _this;
+        var _this = 
         // Should error; base constructor has type T for first arg,
         // which is instantiated with 'number' in the extends clause
-        _this = _super.call(this, "hi") || this;
+        _super.call(this, "hi") || this;
         var x = _this.foo;
         return _this;
     }
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing1.js b/tests/baselines/reference/superCallBeforeThisAccessing1.js
index a5d6ec18ce3..e3aed9e40e9 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing1.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing1.js
@@ -30,8 +30,7 @@ var Base = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this;
-        _this = _super.call(this, i) || this;
+        var _this = _super.call(this, i) || this;
         var s = {
             t: _this._t
         };
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing2.js b/tests/baselines/reference/superCallBeforeThisAccessing2.js
index c7a206dbbbe..91cc3d28dd6 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing2.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing2.js
@@ -24,8 +24,7 @@ var Base = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this;
-        _this = _super.call(this, function () { _this._t; }) || this; // no error. only check when this is directly accessing in constructor
+        var _this = _super.call(this, function () { _this._t; }) || this;
         return _this;
     }
     return D;
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing4.js b/tests/baselines/reference/superCallBeforeThisAccessing4.js
index 311b7ca2183..91acb88ce22 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing4.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing4.js
@@ -34,8 +34,7 @@ var D = (function (_super) {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _this._t;
         return _this;
     }
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing6.js b/tests/baselines/reference/superCallBeforeThisAccessing6.js
index e630d539f14..4eb8e5266c2 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing6.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing6.js
@@ -24,8 +24,7 @@ var Base = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this;
-        _this = _super.call(this, _this) || this;
+        var _this = _super.call(this, _this) || this;
         return _this;
     }
     return D;
diff --git a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType1.js b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType1.js
index 2cfc0bfcbd4..27f3db51453 100644
--- a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType1.js
+++ b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType1.js
@@ -20,8 +20,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         return _this;
     }
     return D;
diff --git a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType2.js b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType2.js
index f9eeadc98e6..a8d5e8008ac 100644
--- a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType2.js
+++ b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType2.js
@@ -19,8 +19,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         return _this;
     }
     return D;
diff --git a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithIncorrectNumberOfTypeArguments1.js b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithIncorrectNumberOfTypeArguments1.js
index 02bec67d7aa..b12a3eef6d4 100644
--- a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithIncorrectNumberOfTypeArguments1.js
+++ b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithIncorrectNumberOfTypeArguments1.js
@@ -25,8 +25,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this;
-        _this = _super.call(this, function (value) { return String(value); }) || this;
+        var _this = _super.call(this, function (value) { return String(value); }) || this;
         return _this;
     }
     return B;
diff --git a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithNoTypeArguments1.js b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithNoTypeArguments1.js
index 55c6ee6f445..c78e6693f16 100644
--- a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithNoTypeArguments1.js
+++ b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithNoTypeArguments1.js
@@ -25,8 +25,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this;
-        _this = _super.call(this, function (value) { return String(value); }) || this;
+        var _this = _super.call(this, function (value) { return String(value); }) || this;
         return _this;
     }
     return B;
diff --git a/tests/baselines/reference/superCallFromClassThatDerivesNonGenericTypeButWithTypeArguments1.js b/tests/baselines/reference/superCallFromClassThatDerivesNonGenericTypeButWithTypeArguments1.js
index 977377e41d4..32d2065dd3f 100644
--- a/tests/baselines/reference/superCallFromClassThatDerivesNonGenericTypeButWithTypeArguments1.js
+++ b/tests/baselines/reference/superCallFromClassThatDerivesNonGenericTypeButWithTypeArguments1.js
@@ -25,8 +25,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this;
-        _this = _super.call(this, function (value) { return String(value); }) || this;
+        var _this = _super.call(this, function (value) { return String(value); }) || this;
         return _this;
     }
     return B;
diff --git a/tests/baselines/reference/superCallInNonStaticMethod.js b/tests/baselines/reference/superCallInNonStaticMethod.js
index 503aee2dcc6..cd84052ca3c 100644
--- a/tests/baselines/reference/superCallInNonStaticMethod.js
+++ b/tests/baselines/reference/superCallInNonStaticMethod.js
@@ -66,8 +66,7 @@ var Doing = (function () {
 var Other = (function (_super) {
     __extends(Other, _super);
     function Other() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _this.propertyInitializer = _super.prototype.instanceMethod.call(_this);
         _this.functionProperty = function () { _super.prototype.instanceMethod.call(_this); };
         _super.prototype.instanceMethod.call(_this);
diff --git a/tests/baselines/reference/superCallInsideClassDeclaration.js b/tests/baselines/reference/superCallInsideClassDeclaration.js
index 326662abdac..b696b4a302f 100644
--- a/tests/baselines/reference/superCallInsideClassDeclaration.js
+++ b/tests/baselines/reference/superCallInsideClassDeclaration.js
@@ -39,8 +39,7 @@ var B = (function (_super) {
         var D = (function (_super) {
             __extends(D, _super);
             function D() {
-                var _this;
-                _this = _super.call(this) || this;
+                var _this = _super.call(this) || this;
                 return _this;
             }
             return D;
diff --git a/tests/baselines/reference/superCallInsideClassExpression.js b/tests/baselines/reference/superCallInsideClassExpression.js
index 5797085726d..829311f237c 100644
--- a/tests/baselines/reference/superCallInsideClassExpression.js
+++ b/tests/baselines/reference/superCallInsideClassExpression.js
@@ -39,8 +39,7 @@ var B = (function (_super) {
         var D = (function (_super) {
             __extends(class_1, _super);
             function class_1() {
-                var _this;
-                _this = _super.call(this) || this;
+                var _this = _super.call(this) || this;
                 return _this;
             }
             return class_1;
diff --git a/tests/baselines/reference/superCallOutsideConstructor.js b/tests/baselines/reference/superCallOutsideConstructor.js
index 65a8b435166..e32bfc66050 100644
--- a/tests/baselines/reference/superCallOutsideConstructor.js
+++ b/tests/baselines/reference/superCallOutsideConstructor.js
@@ -37,8 +37,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _this.x = _this = _super.call(this) || this;
         var y = function () {
             _this = _super.call(this) || this;
diff --git a/tests/baselines/reference/superCallParameterContextualTyping1.js b/tests/baselines/reference/superCallParameterContextualTyping1.js
index 4e4ae47967a..0fe27f493e8 100644
--- a/tests/baselines/reference/superCallParameterContextualTyping1.js
+++ b/tests/baselines/reference/superCallParameterContextualTyping1.js
@@ -28,8 +28,7 @@ var B = (function (_super) {
     __extends(B, _super);
     // Ensure 'value' is of type 'number (and not '{}') by using its 'toExponential()' method.
     function B() {
-        var _this;
-        _this = _super.call(this, function (value) { return String(value.toExponential()); }) || this;
+        var _this = _super.call(this, function (value) { return String(value.toExponential()); }) || this;
         return _this;
     }
     return B;
diff --git a/tests/baselines/reference/superCallParameterContextualTyping2.js b/tests/baselines/reference/superCallParameterContextualTyping2.js
index f3a246c6389..f970be44aff 100644
--- a/tests/baselines/reference/superCallParameterContextualTyping2.js
+++ b/tests/baselines/reference/superCallParameterContextualTyping2.js
@@ -27,8 +27,7 @@ var C = (function (_super) {
     __extends(C, _super);
     // Ensure 'value' is not of type 'any' by invoking it with type arguments.
     function C() {
-        var _this;
-        _this = _super.call(this, function (value) { return String(value()); }) || this;
+        var _this = _super.call(this, function (value) { return String(value()); }) || this;
         return _this;
     }
     return C;
diff --git a/tests/baselines/reference/superCallParameterContextualTyping3.js b/tests/baselines/reference/superCallParameterContextualTyping3.js
index e7b8b355108..6a43d58c471 100644
--- a/tests/baselines/reference/superCallParameterContextualTyping3.js
+++ b/tests/baselines/reference/superCallParameterContextualTyping3.js
@@ -47,10 +47,10 @@ var CBase = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this;
+        var _this = 
         // Should be okay.
         // 'p' should have type 'string'.
-        _this = _super.call(this, {
+        _super.call(this, {
             method: function (p) {
                 p.length;
             }
diff --git a/tests/baselines/reference/superCalls.js b/tests/baselines/reference/superCalls.js
index 2fe7712ce68..99a3b78752c 100644
--- a/tests/baselines/reference/superCalls.js
+++ b/tests/baselines/reference/superCalls.js
@@ -47,8 +47,7 @@ var Derived = (function (_super) {
     __extends(Derived, _super);
     //super call in class constructor of derived type
     function Derived(q) {
-        var _this;
-        _this = _super.call(this, '') || this;
+        var _this = _super.call(this, '') || this;
         _this.q = q;
         //type of super call expression is void
         var p = _this = _super.call(this, '') || this;
diff --git a/tests/baselines/reference/superErrors.js b/tests/baselines/reference/superErrors.js
index 93676c5d8f3..19f0d74f677 100644
--- a/tests/baselines/reference/superErrors.js
+++ b/tests/baselines/reference/superErrors.js
@@ -76,8 +76,7 @@ var User = (function () {
 var RegisteredUser = (function (_super) {
     __extends(RegisteredUser, _super);
     function RegisteredUser() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _this.name = "Frank";
         // super call in an inner function in a constructor
         function inner() {
diff --git a/tests/baselines/reference/superInLambdas.js b/tests/baselines/reference/superInLambdas.js
index 9b4d956dc5a..73ca53c3b5c 100644
--- a/tests/baselines/reference/superInLambdas.js
+++ b/tests/baselines/reference/superInLambdas.js
@@ -85,8 +85,7 @@ var User = (function () {
 var RegisteredUser = (function (_super) {
     __extends(RegisteredUser, _super);
     function RegisteredUser() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _this.name = "Frank";
         // super call in a constructor
         _super.prototype.sayHello.call(_this);
@@ -106,8 +105,7 @@ var RegisteredUser = (function (_super) {
 var RegisteredUser2 = (function (_super) {
     __extends(RegisteredUser2, _super);
     function RegisteredUser2() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _this.name = "Joe";
         // super call in a nested lambda in a constructor 
         var x = function () { return function () { return function () { return _super.prototype.sayHello.call(_this); }; }; };
@@ -123,8 +121,7 @@ var RegisteredUser2 = (function (_super) {
 var RegisteredUser3 = (function (_super) {
     __extends(RegisteredUser3, _super);
     function RegisteredUser3() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _this.name = "Sam";
         // super property in a nested lambda in a constructor 
         var superName = function () { return function () { return function () { return _super.prototype.name; }; }; };
@@ -140,8 +137,7 @@ var RegisteredUser3 = (function (_super) {
 var RegisteredUser4 = (function (_super) {
     __extends(RegisteredUser4, _super);
     function RegisteredUser4() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _this.name = "Mark";
         // super in a nested lambda in a constructor 
         var x = function () { return function () { return _super.prototype.; }; };
diff --git a/tests/baselines/reference/superPropertyAccess1.js b/tests/baselines/reference/superPropertyAccess1.js
index b6559a63a98..0b1e4fc280f 100644
--- a/tests/baselines/reference/superPropertyAccess1.js
+++ b/tests/baselines/reference/superPropertyAccess1.js
@@ -50,8 +50,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _super.prototype.bar.call(_this);
         _super.prototype.x; // error
         return _this;
diff --git a/tests/baselines/reference/superPropertyAccess2.js b/tests/baselines/reference/superPropertyAccess2.js
index eded4e74a7f..7c72ad5d1bb 100644
--- a/tests/baselines/reference/superPropertyAccess2.js
+++ b/tests/baselines/reference/superPropertyAccess2.js
@@ -50,8 +50,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         _super.prototype.bar.call(_this); // error
         _super.prototype.x; // error
         return _this;
diff --git a/tests/baselines/reference/superPropertyAccessNoError.js b/tests/baselines/reference/superPropertyAccessNoError.js
index 2ba460d18f7..88a5da8b8fb 100644
--- a/tests/baselines/reference/superPropertyAccessNoError.js
+++ b/tests/baselines/reference/superPropertyAccessNoError.js
@@ -99,8 +99,7 @@ var SomeBaseClass = (function () {
 var SomeDerivedClass = (function (_super) {
     __extends(SomeDerivedClass, _super);
     function SomeDerivedClass() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         var x = _super.prototype.func.call(_this);
         var x;
         return _this;
diff --git a/tests/baselines/reference/superPropertyAccess_ES5.js b/tests/baselines/reference/superPropertyAccess_ES5.js
index 011c5129e9f..4e817b7bbf1 100644
--- a/tests/baselines/reference/superPropertyAccess_ES5.js
+++ b/tests/baselines/reference/superPropertyAccess_ES5.js
@@ -49,8 +49,7 @@ var MyBase = (function () {
 var MyDerived = (function (_super) {
     __extends(MyDerived, _super);
     function MyDerived() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         var f1 = _super.prototype.getValue.call(_this);
         var f2 = _super.prototype.value;
         return _this;
diff --git a/tests/baselines/reference/superWithGenericSpecialization.js b/tests/baselines/reference/superWithGenericSpecialization.js
index 1152399e6eb..96303dab4ed 100644
--- a/tests/baselines/reference/superWithGenericSpecialization.js
+++ b/tests/baselines/reference/superWithGenericSpecialization.js
@@ -28,8 +28,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this;
-        _this = _super.call(this) || this; // uses the type parameter type of the base class, ie string
+        var _this = _super.call(this) || this;
         return _this;
     }
     return D;
diff --git a/tests/baselines/reference/superWithGenerics.js b/tests/baselines/reference/superWithGenerics.js
index f2580d30c5f..36b48554871 100644
--- a/tests/baselines/reference/superWithGenerics.js
+++ b/tests/baselines/reference/superWithGenerics.js
@@ -20,8 +20,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this;
-        _this = _super.call(this) || this;
+        var _this = _super.call(this) || this;
         return _this;
     }
     return D;
diff --git a/tests/baselines/reference/targetTypeBaseCalls.js b/tests/baselines/reference/targetTypeBaseCalls.js
index a08380b173f..8581526c1b6 100644
--- a/tests/baselines/reference/targetTypeBaseCalls.js
+++ b/tests/baselines/reference/targetTypeBaseCalls.js
@@ -35,8 +35,7 @@ new Foo(function (s) { s = 5; }); // error, if types are applied correctly
 var Bar = (function (_super) {
     __extends(Bar, _super);
     function Bar() {
-        var _this;
-        _this = _super.call(this, function (s) { s = 5; }) || this;
+        var _this = _super.call(this, function (s) { s = 5; }) || this;
         return _this;
     }
     return Bar;
diff --git a/tests/baselines/reference/thisInInvalidContexts.js b/tests/baselines/reference/thisInInvalidContexts.js
index 10629d579ba..7872aa121ed 100644
--- a/tests/baselines/reference/thisInInvalidContexts.js
+++ b/tests/baselines/reference/thisInInvalidContexts.js
@@ -70,8 +70,7 @@ var ClassWithNoInitializer = (function (_super) {
     __extends(ClassWithNoInitializer, _super);
     //'this' in optional super call
     function ClassWithNoInitializer() {
-        var _this;
-        _this = _super.call(this, _this) || this; // Error
+        var _this = _super.call(this, _this) || this;
         return _this;
     }
     return ClassWithNoInitializer;
@@ -80,8 +79,7 @@ var ClassWithInitializer = (function (_super) {
     __extends(ClassWithInitializer, _super);
     //'this' in required super call
     function ClassWithInitializer() {
-        var _this;
-        _this = _super.call(this, _this) || this; // Error
+        var _this = _super.call(this, _this) || this;
         _this.t = 4;
         return _this;
     }
diff --git a/tests/baselines/reference/thisInInvalidContextsExternalModule.js b/tests/baselines/reference/thisInInvalidContextsExternalModule.js
index 444952fea3f..e656824ae66 100644
--- a/tests/baselines/reference/thisInInvalidContextsExternalModule.js
+++ b/tests/baselines/reference/thisInInvalidContextsExternalModule.js
@@ -71,8 +71,7 @@ var ClassWithNoInitializer = (function (_super) {
     __extends(ClassWithNoInitializer, _super);
     //'this' in optional super call
     function ClassWithNoInitializer() {
-        var _this;
-        _this = _super.call(this, _this) || this; // error: "super" has to be called before "this" accessing
+        var _this = _super.call(this, _this) || this;
         return _this;
     }
     return ClassWithNoInitializer;
@@ -81,8 +80,7 @@ var ClassWithInitializer = (function (_super) {
     __extends(ClassWithInitializer, _super);
     //'this' in required super call
     function ClassWithInitializer() {
-        var _this;
-        _this = _super.call(this, _this) || this; // Error
+        var _this = _super.call(this, _this) || this;
         _this.t = 4;
         return _this;
     }
diff --git a/tests/baselines/reference/thisInSuperCall.js b/tests/baselines/reference/thisInSuperCall.js
index f9d9f8694c9..1c1f11ffbc8 100644
--- a/tests/baselines/reference/thisInSuperCall.js
+++ b/tests/baselines/reference/thisInSuperCall.js
@@ -36,8 +36,7 @@ var Base = (function () {
 var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo() {
-        var _this;
-        _this = _super.call(this, _this) || this; // error: "super" has to be called before "this" accessing
+        var _this = _super.call(this, _this) || this;
         return _this;
     }
     return Foo;
@@ -45,8 +44,7 @@ var Foo = (function (_super) {
 var Foo2 = (function (_super) {
     __extends(Foo2, _super);
     function Foo2() {
-        var _this;
-        _this = _super.call(this, _this) || this; // error
+        var _this = _super.call(this, _this) || this;
         _this.p = 0;
         return _this;
     }
@@ -55,8 +53,7 @@ var Foo2 = (function (_super) {
 var Foo3 = (function (_super) {
     __extends(Foo3, _super);
     function Foo3(p) {
-        var _this;
-        _this = _super.call(this, _this) || this; // error
+        var _this = _super.call(this, _this) || this;
         _this.p = p;
         return _this;
     }
diff --git a/tests/baselines/reference/thisInSuperCall1.js b/tests/baselines/reference/thisInSuperCall1.js
index 3185e42dab6..e3eea1fb91d 100644
--- a/tests/baselines/reference/thisInSuperCall1.js
+++ b/tests/baselines/reference/thisInSuperCall1.js
@@ -24,8 +24,7 @@ var Base = (function () {
 var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo(x) {
-        var _this;
-        _this = _super.call(this, _this) || this;
+        var _this = _super.call(this, _this) || this;
         _this.x = x;
         return _this;
     }
diff --git a/tests/baselines/reference/thisInSuperCall2.js b/tests/baselines/reference/thisInSuperCall2.js
index b9f7571868a..6288082ed64 100644
--- a/tests/baselines/reference/thisInSuperCall2.js
+++ b/tests/baselines/reference/thisInSuperCall2.js
@@ -33,8 +33,7 @@ var Base = (function () {
 var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo() {
-        var _this;
-        _this = _super.call(this, _this) || this; // error: "super" has to be called before "this" accessing
+        var _this = _super.call(this, _this) || this;
         return _this;
     }
     return Foo;
@@ -42,8 +41,7 @@ var Foo = (function (_super) {
 var Foo2 = (function (_super) {
     __extends(Foo2, _super);
     function Foo2() {
-        var _this;
-        _this = _super.call(this, _this) || this; // error
+        var _this = _super.call(this, _this) || this;
         _this.x = 0;
         return _this;
     }
diff --git a/tests/baselines/reference/thisInSuperCall3.js b/tests/baselines/reference/thisInSuperCall3.js
index 309ebf93407..6a72f17248f 100644
--- a/tests/baselines/reference/thisInSuperCall3.js
+++ b/tests/baselines/reference/thisInSuperCall3.js
@@ -26,8 +26,7 @@ var Base = (function () {
 var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo() {
-        var _this;
-        _this = _super.call(this, _this) || this;
+        var _this = _super.call(this, _this) || this;
         _this.x = 0;
         return _this;
     }
diff --git a/tests/baselines/reference/tsxDynamicTagName5.js b/tests/baselines/reference/tsxDynamicTagName5.js
index 307cd0fca93..d3bb404ceea 100644
--- a/tests/baselines/reference/tsxDynamicTagName5.js
+++ b/tests/baselines/reference/tsxDynamicTagName5.js
@@ -30,8 +30,7 @@ var React = require("react");
 var Text = (function (_super) {
     __extends(Text, _super);
     function Text() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this._tagName = 'div';
         return _this;
     }
diff --git a/tests/baselines/reference/tsxDynamicTagName7.js b/tests/baselines/reference/tsxDynamicTagName7.js
index 39e30b6ba38..84debfd3e71 100644
--- a/tests/baselines/reference/tsxDynamicTagName7.js
+++ b/tests/baselines/reference/tsxDynamicTagName7.js
@@ -30,8 +30,7 @@ var React = require("react");
 var Text = (function (_super) {
     __extends(Text, _super);
     function Text() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this._tagName = 'div';
         return _this;
     }
diff --git a/tests/baselines/reference/tsxDynamicTagName8.js b/tests/baselines/reference/tsxDynamicTagName8.js
index 77423709347..6166b99f4ac 100644
--- a/tests/baselines/reference/tsxDynamicTagName8.js
+++ b/tests/baselines/reference/tsxDynamicTagName8.js
@@ -30,8 +30,7 @@ var React = require("react");
 var Text = (function (_super) {
     __extends(Text, _super);
     function Text() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this._tagName = 'div';
         return _this;
     }
diff --git a/tests/baselines/reference/tsxDynamicTagName9.js b/tests/baselines/reference/tsxDynamicTagName9.js
index 6b5d130c0b4..928649264c8 100644
--- a/tests/baselines/reference/tsxDynamicTagName9.js
+++ b/tests/baselines/reference/tsxDynamicTagName9.js
@@ -30,8 +30,7 @@ var React = require("react");
 var Text = (function (_super) {
     __extends(Text, _super);
     function Text() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this._tagName = 'div';
         return _this;
     }
diff --git a/tests/baselines/reference/typeGuardOfFormThisMember.js b/tests/baselines/reference/typeGuardOfFormThisMember.js
index 3995ffd447c..541c03dd4b4 100644
--- a/tests/baselines/reference/typeGuardOfFormThisMember.js
+++ b/tests/baselines/reference/typeGuardOfFormThisMember.js
@@ -118,8 +118,7 @@ var Test;
     var File = (function (_super) {
         __extends(File, _super);
         function File(path, content) {
-            var _this;
-            _this = _super.call(this, path) || this;
+            var _this = _super.call(this, path) || this;
             _this.content = content;
             return _this;
         }
diff --git a/tests/baselines/reference/typeGuardOfFormThisMemberErrors.js b/tests/baselines/reference/typeGuardOfFormThisMemberErrors.js
index 14807ddd88c..b61676b40c3 100644
--- a/tests/baselines/reference/typeGuardOfFormThisMemberErrors.js
+++ b/tests/baselines/reference/typeGuardOfFormThisMemberErrors.js
@@ -68,8 +68,7 @@ var Test;
     var File = (function (_super) {
         __extends(File, _super);
         function File(path, content) {
-            var _this;
-            _this = _super.call(this, path) || this;
+            var _this = _super.call(this, path) || this;
             _this.content = content;
             return _this;
         }
diff --git a/tests/baselines/reference/typeRelationships.js b/tests/baselines/reference/typeRelationships.js
index eee99568638..2f97f4b0d1c 100644
--- a/tests/baselines/reference/typeRelationships.js
+++ b/tests/baselines/reference/typeRelationships.js
@@ -72,8 +72,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this;
-        _this = _super.apply(this, arguments) || this;
+        var _this = _super.apply(this, arguments) || this;
         _this.self1 = _this;
         _this.self2 = _this.self;
         _this.self3 = _this.foo();
diff --git a/tests/baselines/reference/unknownSymbols1.js b/tests/baselines/reference/unknownSymbols1.js
index 2c2b3ded1b5..5e2bb509a23 100644
--- a/tests/baselines/reference/unknownSymbols1.js
+++ b/tests/baselines/reference/unknownSymbols1.js
@@ -63,8 +63,7 @@ var C3 = (function () {
 var C4 = (function (_super) {
     __extends(C4, _super);
     function C4() {
-        var _this;
-        _this = _super.call(this, asdf) || this;
+        var _this = _super.call(this, asdf) || this;
         return _this;
     }
     return C4;
diff --git a/tests/baselines/reference/unspecializedConstraints.js b/tests/baselines/reference/unspecializedConstraints.js
index 02927bf558d..7d5a4b9deed 100644
--- a/tests/baselines/reference/unspecializedConstraints.js
+++ b/tests/baselines/reference/unspecializedConstraints.js
@@ -234,8 +234,7 @@ var ts;
     var Property = (function (_super) {
         __extends(Property, _super);
         function Property(name, type, flags) {
-            var _this;
-            _this = _super.call(this) || this;
+            var _this = _super.call(this) || this;
             _this.name = name;
             _this.type = type;
             _this.flags = flags;
@@ -256,8 +255,7 @@ var ts;
     var Signature = (function (_super) {
         __extends(Signature, _super);
         function Signature(typeParameters, parameters, returnType) {
-            var _this;
-            _this = _super.call(this) || this;
+            var _this = _super.call(this) || this;
             _this.typeParameters = typeParameters;
             _this.parameters = parameters;
             _this.returnType = returnType;
@@ -278,8 +276,7 @@ var ts;
     var Parameter = (function (_super) {
         __extends(Parameter, _super);
         function Parameter(name, type, flags) {
-            var _this;
-            _this = _super.call(this) || this;
+            var _this = _super.call(this) || this;
             _this.name = name;
             _this.type = type;
             _this.flags = flags;
diff --git a/tests/baselines/reference/validUseOfThisInSuper.js b/tests/baselines/reference/validUseOfThisInSuper.js
index 3a05ff12ee8..bbd564db366 100644
--- a/tests/baselines/reference/validUseOfThisInSuper.js
+++ b/tests/baselines/reference/validUseOfThisInSuper.js
@@ -24,8 +24,7 @@ var Base = (function () {
 var Super = (function (_super) {
     __extends(Super, _super);
     function Super() {
-        var _this;
-        _this = _super.call(this, (function () { return _this; })()) || this; // ok since this is not the case: The constructor declares parameter properties or the containing class declares instance member variables with initializers.
+        var _this = _super.call(this, (function () { return _this; })()) || this;
         return _this;
     }
     return Super;
diff --git a/tests/baselines/reference/varArgsOnConstructorTypes.js b/tests/baselines/reference/varArgsOnConstructorTypes.js
index 9c1c8f8c29d..0875f2ba1dd 100644
--- a/tests/baselines/reference/varArgsOnConstructorTypes.js
+++ b/tests/baselines/reference/varArgsOnConstructorTypes.js
@@ -41,8 +41,7 @@ define(["require", "exports"], function (require, exports) {
     var B = (function (_super) {
         __extends(B, _super);
         function B(element, url) {
-            var _this;
-            _this = _super.call(this, element) || this;
+            var _this = _super.call(this, element) || this;
             _this.p1 = element;
             _this.p2 = url;
             return _this;

From 86088d0e7e9b7d31b04f4e4fb4327bb121e42def Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Sat, 3 Sep 2016 00:30:40 -0700
Subject: [PATCH 13/47] Always perform `this` captures after default & rest
 parameters.

---
 src/compiler/transformers/es6.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/compiler/transformers/es6.ts b/src/compiler/transformers/es6.ts
index 85838112fc3..44089326f7f 100644
--- a/src/compiler/transformers/es6.ts
+++ b/src/compiler/transformers/es6.ts
@@ -791,10 +791,10 @@ namespace ts {
             }
 
             if (constructor) {
-                Debug.assert(statementOffset >= 0, "statementOffset not initialized correctly!");
-                statementOffset = declareOrCaptureThisForConstructorIfNeeded(statements, constructor, !!extendsClauseElement, statementOffset);
                 addDefaultValueAssignmentsIfNeeded(statements, constructor);
                 addRestParameterIfNeeded(statements, constructor, hasSynthesizedSuper);
+                Debug.assert(statementOffset >= 0, "statementOffset not initialized correctly!");
+                statementOffset = declareOrCaptureThisForConstructorIfNeeded(statements, constructor, !!extendsClauseElement, statementOffset);
             }
 
             addDefaultSuperCallIfNeeded(statements, constructor, extendsClauseElement, hasSynthesizedSuper);

From dd27139f39795fd0d83e8189c7a932364afe8044 Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Sat, 3 Sep 2016 00:31:09 -0700
Subject: [PATCH 14/47] Accepted baselines.

---
 tests/baselines/reference/es6ClassTest.js             | 2 +-
 tests/baselines/reference/optionalParamArgsTest.js    | 2 +-
 tests/baselines/reference/superAccess2.js             | 2 +-
 tests/baselines/reference/superInConstructorParam1.js | 2 +-
 4 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/tests/baselines/reference/es6ClassTest.js b/tests/baselines/reference/es6ClassTest.js
index d0879152544..067e57c2581 100644
--- a/tests/baselines/reference/es6ClassTest.js
+++ b/tests/baselines/reference/es6ClassTest.js
@@ -102,8 +102,8 @@ var Bar = (function () {
 var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo(x, y, z) {
-        var _this = _super.call(this, x) || this;
         if (z === void 0) { z = 0; }
+        var _this = _super.call(this, x) || this;
         _this.y = y;
         _this.z = z;
         _this.gar = 0;
diff --git a/tests/baselines/reference/optionalParamArgsTest.js b/tests/baselines/reference/optionalParamArgsTest.js
index e93058d71d2..374b0956509 100644
--- a/tests/baselines/reference/optionalParamArgsTest.js
+++ b/tests/baselines/reference/optionalParamArgsTest.js
@@ -161,8 +161,8 @@ var C1 = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2(v2) {
-        var _this = _super.call(this, v2) || this;
         if (v2 === void 0) { v2 = 6; }
+        var _this = _super.call(this, v2) || this;
         return _this;
     }
     return C2;
diff --git a/tests/baselines/reference/superAccess2.js b/tests/baselines/reference/superAccess2.js
index 54c59978151..da19770584a 100644
--- a/tests/baselines/reference/superAccess2.js
+++ b/tests/baselines/reference/superAccess2.js
@@ -41,10 +41,10 @@ var Q = (function (_super) {
     __extends(Q, _super);
     // Super is not allowed in constructor args
     function Q(z, zz, zzz) {
-        var _this = _super.call(this) || this;
         if (z === void 0) { z = _super.; }
         if (zz === void 0) { zz = _super.; }
         if (zzz === void 0) { zzz = function () { return _super.; }; }
+        var _this = _super.call(this) || this;
         _this.z = z;
         _this.xx = _super.prototype.;
         return _this;
diff --git a/tests/baselines/reference/superInConstructorParam1.js b/tests/baselines/reference/superInConstructorParam1.js
index 7519a8253ec..8c99b649917 100644
--- a/tests/baselines/reference/superInConstructorParam1.js
+++ b/tests/baselines/reference/superInConstructorParam1.js
@@ -27,8 +27,8 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C(a) {
-        var _this;
         if (a === void 0) { a = _super.foo.call(_this); }
+        var _this;
         return _this;
     }
     return C;

From f3dcaae0f02d597a6f0918488fde203d08570686 Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Sat, 3 Sep 2016 01:09:28 -0700
Subject: [PATCH 15/47] Added a test for branched returns at the end of a
 constructor.

---
 ...edClassConstructorWithExplicitReturns01.ts | 36 +++++++++++++++++++
 1 file changed, 36 insertions(+)
 create mode 100644 tests/cases/compiler/derivedClassConstructorWithExplicitReturns01.ts

diff --git a/tests/cases/compiler/derivedClassConstructorWithExplicitReturns01.ts b/tests/cases/compiler/derivedClassConstructorWithExplicitReturns01.ts
new file mode 100644
index 00000000000..2475eac0bb2
--- /dev/null
+++ b/tests/cases/compiler/derivedClassConstructorWithExplicitReturns01.ts
@@ -0,0 +1,36 @@
+// @target: es5
+// @sourcemap: true
+
+class C {
+    cProp = 10;
+
+    foo() { return "this never gets used."; }
+
+    constructor(value: number) {
+        return {
+            cProp: value,
+            foo() {
+                return "well this looks kinda C-ish.";
+            }
+        }
+    }
+}
+
+class D extends C {
+    dProp = () => this;
+
+    constructor(a = 100) {
+        super(a);
+
+        if (Math.random() < 0.5) {
+            "You win!"
+            return {
+                cProp: 1,
+                dProp: () => this,
+                foo() { return "You win!!!!!" }
+            };
+        }
+        else
+            return null;
+    }
+}
\ No newline at end of file

From 1be4cee0c6fd9e19869e332d57672d74bc5f2dbd Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Sat, 3 Sep 2016 01:10:07 -0700
Subject: [PATCH 16/47] Accepted baselines.

---
 ...edClassConstructorWithExplicitReturns01.js |  76 +++
 ...assConstructorWithExplicitReturns01.js.map |   2 +
 ...tructorWithExplicitReturns01.sourcemap.txt | 583 ++++++++++++++++++
 ...ssConstructorWithExplicitReturns01.symbols |  66 ++
 ...lassConstructorWithExplicitReturns01.types |  85 +++
 5 files changed, 812 insertions(+)
 create mode 100644 tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.js
 create mode 100644 tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.js.map
 create mode 100644 tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.sourcemap.txt
 create mode 100644 tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.symbols
 create mode 100644 tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.types

diff --git a/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.js b/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.js
new file mode 100644
index 00000000000..de1e409b55f
--- /dev/null
+++ b/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.js
@@ -0,0 +1,76 @@
+//// [derivedClassConstructorWithExplicitReturns01.ts]
+
+class C {
+    cProp = 10;
+
+    foo() { return "this never gets used."; }
+
+    constructor(value: number) {
+        return {
+            cProp: value,
+            foo() {
+                return "well this looks kinda C-ish.";
+            }
+        }
+    }
+}
+
+class D extends C {
+    dProp = () => this;
+
+    constructor(a = 100) {
+        super(a);
+
+        if (Math.random() < 0.5) {
+            "You win!"
+            return {
+                cProp: 1,
+                dProp: () => this,
+                foo() { return "You win!!!!!" }
+            };
+        }
+        else
+            return null;
+    }
+}
+
+//// [derivedClassConstructorWithExplicitReturns01.js]
+var __extends = (this && this.__extends) || function (d, b) {
+    for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p];
+    function __() { this.constructor = d; }
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
+};
+var C = (function () {
+    function C(value) {
+        this.cProp = 10;
+        return {
+            cProp: value,
+            foo: function () {
+                return "well this looks kinda C-ish.";
+            }
+        };
+    }
+    C.prototype.foo = function () { return "this never gets used."; };
+    return C;
+}());
+var D = (function (_super) {
+    __extends(D, _super);
+    function D(a) {
+        if (a === void 0) { a = 100; }
+        var _this = _super.call(this, a) || this;
+        _this.dProp = function () { return _this; };
+        if (Math.random() < 0.5) {
+            "You win!";
+            return {
+                cProp: 1,
+                dProp: function () { return _this; },
+                foo: function () { return "You win!!!!!"; }
+            };
+        }
+        else
+            return null;
+        return _this;
+    }
+    return D;
+}(C));
+//# sourceMappingURL=derivedClassConstructorWithExplicitReturns01.js.map
\ No newline at end of file
diff --git a/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.js.map b/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.js.map
new file mode 100644
index 00000000000..dd7aedd1a98
--- /dev/null
+++ b/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.js.map
@@ -0,0 +1,2 @@
+//// [derivedClassConstructorWithExplicitReturns01.js.map]
+{"version":3,"file":"derivedClassConstructorWithExplicitReturns01.js","sourceRoot":"","sources":["derivedClassConstructorWithExplicitReturns01.ts"],"names":[],"mappings":";;;;;AACA;IAKI,WAAY,KAAa;QAJzB,UAAK,GAAG,EAAE,CAAC;QAKP,MAAM,CAAC;YACH,KAAK,EAAE,KAAK;YACZ,GAAG;gBACC,MAAM,CAAC,8BAA8B,CAAC;YAC1C,CAAC;SACJ,CAAA;IACL,CAAC;IATD,eAAG,GAAH,cAAQ,MAAM,CAAC,uBAAuB,CAAC,CAAC,CAAC;IAU7C,QAAC;AAAD,CAAC,AAbD,IAaC;AAED;IAAgB,qBAAC;IAGb,WAAY,CAAO;QAAP,kBAAA,EAAA,OAAO;QAAnB,YACI,kBAAM,CAAC,CAAC,SAYX;QAfD,WAAK,GAAG,cAAM,OAAA,KAAI,EAAJ,CAAI,CAAC;QAKf,EAAE,CAAC,CAAC,IAAI,CAAC,MAAM,EAAE,GAAG,GAAG,CAAC,CAAC,CAAC;YACtB,UAAU,CAAA;YACV,MAAM,CAAC;gBACH,KAAK,EAAE,CAAC;gBACR,KAAK,EAAE,cAAM,OAAA,KAAI,EAAJ,CAAI;gBACjB,GAAG,gBAAK,MAAM,CAAC,cAAc,CAAA,CAAC,CAAC;aAClC,CAAC;QACN,CAAC;QACD,IAAI;YACA,MAAM,CAAC,IAAI,CAAC;;IACpB,CAAC;IACL,QAAC;AAAD,CAAC,AAjBD,CAAgB,CAAC,GAiBhB"}
\ No newline at end of file
diff --git a/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.sourcemap.txt b/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.sourcemap.txt
new file mode 100644
index 00000000000..5f41ab56300
--- /dev/null
+++ b/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.sourcemap.txt
@@ -0,0 +1,583 @@
+===================================================================
+JsFile: derivedClassConstructorWithExplicitReturns01.js
+mapUrl: derivedClassConstructorWithExplicitReturns01.js.map
+sourceRoot: 
+sources: derivedClassConstructorWithExplicitReturns01.ts
+===================================================================
+-------------------------------------------------------------------
+emittedFile:tests/cases/compiler/derivedClassConstructorWithExplicitReturns01.js
+sourceFile:derivedClassConstructorWithExplicitReturns01.ts
+-------------------------------------------------------------------
+>>>var __extends = (this && this.__extends) || function (d, b) {
+>>>    for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p];
+>>>    function __() { this.constructor = d; }
+>>>    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
+>>>};
+>>>var C = (function () {
+1 >
+2 >^^^^^^^^^^^^^^^^^^^^^^^^->
+1 >
+  >
+1 >Emitted(6, 1) Source(2, 1) + SourceIndex(0)
+---
+>>>    function C(value) {
+1->^^^^
+2 >    ^^^^^^^^^^^
+3 >               ^^^^^
+4 >                    ^^^^^->
+1->class C {
+  >    cProp = 10;
+  >
+  >    foo() { return "this never gets used."; }
+  >
+  >    
+2 >    constructor(
+3 >               value: number
+1->Emitted(7, 5) Source(7, 5) + SourceIndex(0)
+2 >Emitted(7, 16) Source(7, 17) + SourceIndex(0)
+3 >Emitted(7, 21) Source(7, 30) + SourceIndex(0)
+---
+>>>        this.cProp = 10;
+1->^^^^^^^^
+2 >        ^^^^^^^^^^
+3 >                  ^^^
+4 >                     ^^
+5 >                       ^
+1->
+2 >        cProp
+3 >                   = 
+4 >                     10
+5 >                       ;
+1->Emitted(8, 9) Source(3, 5) + SourceIndex(0)
+2 >Emitted(8, 19) Source(3, 10) + SourceIndex(0)
+3 >Emitted(8, 22) Source(3, 13) + SourceIndex(0)
+4 >Emitted(8, 24) Source(3, 15) + SourceIndex(0)
+5 >Emitted(8, 25) Source(3, 16) + SourceIndex(0)
+---
+>>>        return {
+1 >^^^^^^^^
+2 >        ^^^^^^
+3 >              ^
+4 >               ^^^^^^^^^^^->
+1 >
+  >
+  >    foo() { return "this never gets used."; }
+  >
+  >    constructor(value: number) {
+  >        
+2 >        return
+3 >               
+1 >Emitted(9, 9) Source(8, 9) + SourceIndex(0)
+2 >Emitted(9, 15) Source(8, 15) + SourceIndex(0)
+3 >Emitted(9, 16) Source(8, 16) + SourceIndex(0)
+---
+>>>            cProp: value,
+1->^^^^^^^^^^^^
+2 >            ^^^^^
+3 >                 ^^
+4 >                   ^^^^^
+5 >                        ^^^^^^^->
+1->{
+  >            
+2 >            cProp
+3 >                 : 
+4 >                   value
+1->Emitted(10, 13) Source(9, 13) + SourceIndex(0)
+2 >Emitted(10, 18) Source(9, 18) + SourceIndex(0)
+3 >Emitted(10, 20) Source(9, 20) + SourceIndex(0)
+4 >Emitted(10, 25) Source(9, 25) + SourceIndex(0)
+---
+>>>            foo: function () {
+1->^^^^^^^^^^^^
+2 >            ^^^
+3 >               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
+1->,
+  >            
+2 >            foo
+1->Emitted(11, 13) Source(10, 13) + SourceIndex(0)
+2 >Emitted(11, 16) Source(10, 16) + SourceIndex(0)
+---
+>>>                return "well this looks kinda C-ish.";
+1->^^^^^^^^^^^^^^^^
+2 >                ^^^^^^
+3 >                      ^
+4 >                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+5 >                                                     ^
+1->() {
+  >                
+2 >                return
+3 >                       
+4 >                       "well this looks kinda C-ish."
+5 >                                                     ;
+1->Emitted(12, 17) Source(11, 17) + SourceIndex(0)
+2 >Emitted(12, 23) Source(11, 23) + SourceIndex(0)
+3 >Emitted(12, 24) Source(11, 24) + SourceIndex(0)
+4 >Emitted(12, 54) Source(11, 54) + SourceIndex(0)
+5 >Emitted(12, 55) Source(11, 55) + SourceIndex(0)
+---
+>>>            }
+1 >^^^^^^^^^^^^
+2 >            ^
+1 >
+  >            
+2 >            }
+1 >Emitted(13, 13) Source(12, 13) + SourceIndex(0)
+2 >Emitted(13, 14) Source(12, 14) + SourceIndex(0)
+---
+>>>        };
+1 >^^^^^^^^^
+2 >         ^
+1 >
+  >        }
+2 >         
+1 >Emitted(14, 10) Source(13, 10) + SourceIndex(0)
+2 >Emitted(14, 11) Source(13, 10) + SourceIndex(0)
+---
+>>>    }
+1 >^^^^
+2 >    ^
+3 >     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
+1 >
+  >    
+2 >    }
+1 >Emitted(15, 5) Source(14, 5) + SourceIndex(0)
+2 >Emitted(15, 6) Source(14, 6) + SourceIndex(0)
+---
+>>>    C.prototype.foo = function () { return "this never gets used."; };
+1->^^^^
+2 >    ^^^^^^^^^^^^^^^
+3 >                   ^^^
+4 >                      ^^^^^^^^^^^^^^
+5 >                                    ^^^^^^
+6 >                                          ^
+7 >                                           ^^^^^^^^^^^^^^^^^^^^^^^
+8 >                                                                  ^
+9 >                                                                   ^
+10>                                                                    ^
+1->
+2 >    foo
+3 >                   
+4 >                      foo() { 
+5 >                                    return
+6 >                                           
+7 >                                           "this never gets used."
+8 >                                                                  ;
+9 >                                                                    
+10>                                                                    }
+1->Emitted(16, 5) Source(5, 5) + SourceIndex(0)
+2 >Emitted(16, 20) Source(5, 8) + SourceIndex(0)
+3 >Emitted(16, 23) Source(5, 5) + SourceIndex(0)
+4 >Emitted(16, 37) Source(5, 13) + SourceIndex(0)
+5 >Emitted(16, 43) Source(5, 19) + SourceIndex(0)
+6 >Emitted(16, 44) Source(5, 20) + SourceIndex(0)
+7 >Emitted(16, 67) Source(5, 43) + SourceIndex(0)
+8 >Emitted(16, 68) Source(5, 44) + SourceIndex(0)
+9 >Emitted(16, 69) Source(5, 45) + SourceIndex(0)
+10>Emitted(16, 70) Source(5, 46) + SourceIndex(0)
+---
+>>>    return C;
+1 >^^^^
+2 >    ^^^^^^^^
+1 >
+  >
+  >    constructor(value: number) {
+  >        return {
+  >            cProp: value,
+  >            foo() {
+  >                return "well this looks kinda C-ish.";
+  >            }
+  >        }
+  >    }
+  >
+2 >    }
+1 >Emitted(17, 5) Source(15, 1) + SourceIndex(0)
+2 >Emitted(17, 13) Source(15, 2) + SourceIndex(0)
+---
+>>>}());
+1 >
+2 >^
+3 > 
+4 > ^^^^
+5 >     ^^^^^^^^^^^^^^^^^^^^^^^^->
+1 >
+2 >}
+3 > 
+4 > class C {
+  >     cProp = 10;
+  > 
+  >     foo() { return "this never gets used."; }
+  > 
+  >     constructor(value: number) {
+  >         return {
+  >             cProp: value,
+  >             foo() {
+  >                 return "well this looks kinda C-ish.";
+  >             }
+  >         }
+  >     }
+  > }
+1 >Emitted(18, 1) Source(15, 1) + SourceIndex(0)
+2 >Emitted(18, 2) Source(15, 2) + SourceIndex(0)
+3 >Emitted(18, 2) Source(2, 1) + SourceIndex(0)
+4 >Emitted(18, 6) Source(15, 2) + SourceIndex(0)
+---
+>>>var D = (function (_super) {
+1->
+2 >^^^^^^^^^^^^^^^^^^^^^^^^^^->
+1->
+  >
+  >
+1->Emitted(19, 1) Source(17, 1) + SourceIndex(0)
+---
+>>>    __extends(D, _super);
+1->^^^^
+2 >    ^^^^^^^^^^^^^^^^^^^^^
+1->class D extends 
+2 >    C
+1->Emitted(20, 5) Source(17, 17) + SourceIndex(0)
+2 >Emitted(20, 26) Source(17, 18) + SourceIndex(0)
+---
+>>>    function D(a) {
+1 >^^^^
+2 >    ^^^^^^^^^^^
+3 >               ^
+4 >                ^^^^^^^^^^^^^^^^^^^^^^^->
+1 > {
+  >    dProp = () => this;
+  >
+  >    
+2 >    constructor(
+3 >               a = 100
+1 >Emitted(21, 5) Source(20, 5) + SourceIndex(0)
+2 >Emitted(21, 16) Source(20, 17) + SourceIndex(0)
+3 >Emitted(21, 17) Source(20, 24) + SourceIndex(0)
+---
+>>>        if (a === void 0) { a = 100; }
+1->^^^^^^^^
+2 >        ^^^^^^^^^^^^^^^^^^
+3 >                          ^^
+4 >                            ^^^^^^^
+5 >                                   ^^^^^^^^^^^^^^^->
+1->
+2 >        
+3 >                          
+4 >                            a = 100
+1->Emitted(22, 9) Source(20, 17) + SourceIndex(0)
+2 >Emitted(22, 27) Source(20, 17) + SourceIndex(0)
+3 >Emitted(22, 29) Source(20, 17) + SourceIndex(0)
+4 >Emitted(22, 36) Source(20, 24) + SourceIndex(0)
+---
+>>>        var _this = _super.call(this, a) || this;
+1->^^^^^^^^
+2 >        ^^^^^^^^^^^^
+3 >                    ^^^^^^^^^^^^^^^^^^
+4 >                                      ^
+5 >                                       ^
+6 >                                        ^^^^^^^^^
+7 >                                                 ^^^^->
+1->
+2 >        constructor(a = 100) {
+  >                
+3 >                    super(
+4 >                                      a
+5 >                                       )
+6 >                                        ;
+  >                                        
+  >                                                if (Math.random() < 0.5) {
+  >                                                    "You win!"
+  >                                                    return {
+  >                                                        cProp: 1,
+  >                                                        dProp: () => this,
+  >                                                        foo() { return "You win!!!!!" }
+  >                                                    };
+  >                                                }
+  >                                                else
+  >                                                    return null;
+  >                                            }
+1->Emitted(23, 9) Source(20, 5) + SourceIndex(0)
+2 >Emitted(23, 21) Source(21, 9) + SourceIndex(0)
+3 >Emitted(23, 39) Source(21, 15) + SourceIndex(0)
+4 >Emitted(23, 40) Source(21, 16) + SourceIndex(0)
+5 >Emitted(23, 41) Source(21, 17) + SourceIndex(0)
+6 >Emitted(23, 50) Source(33, 6) + SourceIndex(0)
+---
+>>>        _this.dProp = function () { return _this; };
+1->^^^^^^^^
+2 >        ^^^^^^^^^^^
+3 >                   ^^^
+4 >                      ^^^^^^^^^^^^^^
+5 >                                    ^^^^^^^
+6 >                                           ^^^^^
+7 >                                                ^^
+8 >                                                  ^
+9 >                                                   ^
+1->
+2 >        dProp
+3 >                    = 
+4 >                      () => 
+5 >                                    
+6 >                                           this
+7 >                                                
+8 >                                                  this
+9 >                                                   ;
+1->Emitted(24, 9) Source(18, 5) + SourceIndex(0)
+2 >Emitted(24, 20) Source(18, 10) + SourceIndex(0)
+3 >Emitted(24, 23) Source(18, 13) + SourceIndex(0)
+4 >Emitted(24, 37) Source(18, 19) + SourceIndex(0)
+5 >Emitted(24, 44) Source(18, 19) + SourceIndex(0)
+6 >Emitted(24, 49) Source(18, 23) + SourceIndex(0)
+7 >Emitted(24, 51) Source(18, 19) + SourceIndex(0)
+8 >Emitted(24, 52) Source(18, 23) + SourceIndex(0)
+9 >Emitted(24, 53) Source(18, 24) + SourceIndex(0)
+---
+>>>        if (Math.random() < 0.5) {
+1 >^^^^^^^^
+2 >        ^^
+3 >          ^
+4 >           ^
+5 >            ^^^^
+6 >                ^
+7 >                 ^^^^^^
+8 >                       ^^
+9 >                         ^^^
+10>                            ^^^
+11>                               ^
+12>                                ^
+13>                                 ^
+1 >
+  >
+  >    constructor(a = 100) {
+  >        super(a);
+  >
+  >        
+2 >        if
+3 >           
+4 >           (
+5 >            Math
+6 >                .
+7 >                 random
+8 >                       ()
+9 >                          < 
+10>                            0.5
+11>                               )
+12>                                 
+13>                                 {
+1 >Emitted(25, 9) Source(23, 9) + SourceIndex(0)
+2 >Emitted(25, 11) Source(23, 11) + SourceIndex(0)
+3 >Emitted(25, 12) Source(23, 12) + SourceIndex(0)
+4 >Emitted(25, 13) Source(23, 13) + SourceIndex(0)
+5 >Emitted(25, 17) Source(23, 17) + SourceIndex(0)
+6 >Emitted(25, 18) Source(23, 18) + SourceIndex(0)
+7 >Emitted(25, 24) Source(23, 24) + SourceIndex(0)
+8 >Emitted(25, 26) Source(23, 26) + SourceIndex(0)
+9 >Emitted(25, 29) Source(23, 29) + SourceIndex(0)
+10>Emitted(25, 32) Source(23, 32) + SourceIndex(0)
+11>Emitted(25, 33) Source(23, 33) + SourceIndex(0)
+12>Emitted(25, 34) Source(23, 34) + SourceIndex(0)
+13>Emitted(25, 35) Source(23, 35) + SourceIndex(0)
+---
+>>>            "You win!";
+1 >^^^^^^^^^^^^
+2 >            ^^^^^^^^^^
+3 >                      ^
+1 >
+  >            
+2 >            "You win!"
+3 >                      
+1 >Emitted(26, 13) Source(24, 13) + SourceIndex(0)
+2 >Emitted(26, 23) Source(24, 23) + SourceIndex(0)
+3 >Emitted(26, 24) Source(24, 23) + SourceIndex(0)
+---
+>>>            return {
+1 >^^^^^^^^^^^^
+2 >            ^^^^^^
+3 >                  ^
+4 >                   ^^^^^^^->
+1 >
+  >            
+2 >            return
+3 >                   
+1 >Emitted(27, 13) Source(25, 13) + SourceIndex(0)
+2 >Emitted(27, 19) Source(25, 19) + SourceIndex(0)
+3 >Emitted(27, 20) Source(25, 20) + SourceIndex(0)
+---
+>>>                cProp: 1,
+1->^^^^^^^^^^^^^^^^
+2 >                ^^^^^
+3 >                     ^^
+4 >                       ^
+5 >                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
+1->{
+  >                
+2 >                cProp
+3 >                     : 
+4 >                       1
+1->Emitted(28, 17) Source(26, 17) + SourceIndex(0)
+2 >Emitted(28, 22) Source(26, 22) + SourceIndex(0)
+3 >Emitted(28, 24) Source(26, 24) + SourceIndex(0)
+4 >Emitted(28, 25) Source(26, 25) + SourceIndex(0)
+---
+>>>                dProp: function () { return _this; },
+1->^^^^^^^^^^^^^^^^
+2 >                ^^^^^
+3 >                     ^^
+4 >                       ^^^^^^^^^^^^^^
+5 >                                     ^^^^^^^
+6 >                                            ^^^^^
+7 >                                                 ^^
+8 >                                                   ^
+9 >                                                    ^^^^^^^^->
+1->,
+  >                
+2 >                dProp
+3 >                     : 
+4 >                       () => 
+5 >                                     
+6 >                                            this
+7 >                                                 
+8 >                                                   this
+1->Emitted(29, 17) Source(27, 17) + SourceIndex(0)
+2 >Emitted(29, 22) Source(27, 22) + SourceIndex(0)
+3 >Emitted(29, 24) Source(27, 24) + SourceIndex(0)
+4 >Emitted(29, 38) Source(27, 30) + SourceIndex(0)
+5 >Emitted(29, 45) Source(27, 30) + SourceIndex(0)
+6 >Emitted(29, 50) Source(27, 34) + SourceIndex(0)
+7 >Emitted(29, 52) Source(27, 30) + SourceIndex(0)
+8 >Emitted(29, 53) Source(27, 34) + SourceIndex(0)
+---
+>>>                foo: function () { return "You win!!!!!"; }
+1->^^^^^^^^^^^^^^^^
+2 >                ^^^
+3 >                   ^^^^^^^^^^^^^^^^
+4 >                                   ^^^^^^
+5 >                                         ^
+6 >                                          ^^^^^^^^^^^^^^
+7 >                                                        ^
+8 >                                                         ^
+9 >                                                          ^
+1->,
+  >                
+2 >                foo
+3 >                   () { 
+4 >                                   return
+5 >                                          
+6 >                                          "You win!!!!!"
+7 >                                                        
+8 >                                                          
+9 >                                                          }
+1->Emitted(30, 17) Source(28, 17) + SourceIndex(0)
+2 >Emitted(30, 20) Source(28, 20) + SourceIndex(0)
+3 >Emitted(30, 36) Source(28, 25) + SourceIndex(0)
+4 >Emitted(30, 42) Source(28, 31) + SourceIndex(0)
+5 >Emitted(30, 43) Source(28, 32) + SourceIndex(0)
+6 >Emitted(30, 57) Source(28, 46) + SourceIndex(0)
+7 >Emitted(30, 58) Source(28, 46) + SourceIndex(0)
+8 >Emitted(30, 59) Source(28, 47) + SourceIndex(0)
+9 >Emitted(30, 60) Source(28, 48) + SourceIndex(0)
+---
+>>>            };
+1 >^^^^^^^^^^^^^
+2 >             ^
+1 >
+  >            }
+2 >             ;
+1 >Emitted(31, 14) Source(29, 14) + SourceIndex(0)
+2 >Emitted(31, 15) Source(29, 15) + SourceIndex(0)
+---
+>>>        }
+1 >^^^^^^^^
+2 >        ^
+3 >         ^^^^->
+1 >
+  >        
+2 >        }
+1 >Emitted(32, 9) Source(30, 9) + SourceIndex(0)
+2 >Emitted(32, 10) Source(30, 10) + SourceIndex(0)
+---
+>>>        else
+1->^^^^^^^^
+2 >        ^^^^
+3 >            ^^^^^^^^^^^^^->
+1->
+  >        
+2 >        else
+1->Emitted(33, 9) Source(31, 9) + SourceIndex(0)
+2 >Emitted(33, 13) Source(31, 13) + SourceIndex(0)
+---
+>>>            return null;
+1->^^^^^^^^^^^^
+2 >            ^^^^^^
+3 >                  ^
+4 >                   ^^^^
+5 >                       ^
+1->
+  >            
+2 >            return
+3 >                   
+4 >                   null
+5 >                       ;
+1->Emitted(34, 13) Source(32, 13) + SourceIndex(0)
+2 >Emitted(34, 19) Source(32, 19) + SourceIndex(0)
+3 >Emitted(34, 20) Source(32, 20) + SourceIndex(0)
+4 >Emitted(34, 24) Source(32, 24) + SourceIndex(0)
+5 >Emitted(34, 25) Source(32, 25) + SourceIndex(0)
+---
+>>>        return _this;
+>>>    }
+1 >^^^^
+2 >    ^
+3 >     ^^^^^^^^^->
+1 >
+  >    
+2 >    }
+1 >Emitted(36, 5) Source(33, 5) + SourceIndex(0)
+2 >Emitted(36, 6) Source(33, 6) + SourceIndex(0)
+---
+>>>    return D;
+1->^^^^
+2 >    ^^^^^^^^
+1->
+  >
+2 >    }
+1->Emitted(37, 5) Source(34, 1) + SourceIndex(0)
+2 >Emitted(37, 13) Source(34, 2) + SourceIndex(0)
+---
+>>>}(C));
+1 >
+2 >^
+3 > 
+4 > ^
+5 >  ^
+6 >   ^^^
+7 >      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
+1 >
+2 >}
+3 > 
+4 > class D extends 
+5 >  C
+6 >    {
+  >       dProp = () => this;
+  >   
+  >       constructor(a = 100) {
+  >           super(a);
+  >   
+  >           if (Math.random() < 0.5) {
+  >               "You win!"
+  >               return {
+  >                   cProp: 1,
+  >                   dProp: () => this,
+  >                   foo() { return "You win!!!!!" }
+  >               };
+  >           }
+  >           else
+  >               return null;
+  >       }
+  >   }
+1 >Emitted(38, 1) Source(34, 1) + SourceIndex(0)
+2 >Emitted(38, 2) Source(34, 2) + SourceIndex(0)
+3 >Emitted(38, 2) Source(17, 1) + SourceIndex(0)
+4 >Emitted(38, 3) Source(17, 17) + SourceIndex(0)
+5 >Emitted(38, 4) Source(17, 18) + SourceIndex(0)
+6 >Emitted(38, 7) Source(34, 2) + SourceIndex(0)
+---
+>>>//# sourceMappingURL=derivedClassConstructorWithExplicitReturns01.js.map
\ No newline at end of file
diff --git a/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.symbols b/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.symbols
new file mode 100644
index 00000000000..ee043fcfe71
--- /dev/null
+++ b/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.symbols
@@ -0,0 +1,66 @@
+=== tests/cases/compiler/derivedClassConstructorWithExplicitReturns01.ts ===
+
+class C {
+>C : Symbol(C, Decl(derivedClassConstructorWithExplicitReturns01.ts, 0, 0))
+
+    cProp = 10;
+>cProp : Symbol(C.cProp, Decl(derivedClassConstructorWithExplicitReturns01.ts, 1, 9))
+
+    foo() { return "this never gets used."; }
+>foo : Symbol(C.foo, Decl(derivedClassConstructorWithExplicitReturns01.ts, 2, 15))
+
+    constructor(value: number) {
+>value : Symbol(value, Decl(derivedClassConstructorWithExplicitReturns01.ts, 6, 16))
+
+        return {
+            cProp: value,
+>cProp : Symbol(cProp, Decl(derivedClassConstructorWithExplicitReturns01.ts, 7, 16))
+>value : Symbol(value, Decl(derivedClassConstructorWithExplicitReturns01.ts, 6, 16))
+
+            foo() {
+>foo : Symbol(foo, Decl(derivedClassConstructorWithExplicitReturns01.ts, 8, 25))
+
+                return "well this looks kinda C-ish.";
+            }
+        }
+    }
+}
+
+class D extends C {
+>D : Symbol(D, Decl(derivedClassConstructorWithExplicitReturns01.ts, 14, 1))
+>C : Symbol(C, Decl(derivedClassConstructorWithExplicitReturns01.ts, 0, 0))
+
+    dProp = () => this;
+>dProp : Symbol(D.dProp, Decl(derivedClassConstructorWithExplicitReturns01.ts, 16, 19))
+>this : Symbol(D, Decl(derivedClassConstructorWithExplicitReturns01.ts, 14, 1))
+
+    constructor(a = 100) {
+>a : Symbol(a, Decl(derivedClassConstructorWithExplicitReturns01.ts, 19, 16))
+
+        super(a);
+>super : Symbol(C, Decl(derivedClassConstructorWithExplicitReturns01.ts, 0, 0))
+>a : Symbol(a, Decl(derivedClassConstructorWithExplicitReturns01.ts, 19, 16))
+
+        if (Math.random() < 0.5) {
+>Math.random : Symbol(Math.random, Decl(lib.d.ts, --, --))
+>Math : Symbol(Math, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --))
+>random : Symbol(Math.random, Decl(lib.d.ts, --, --))
+
+            "You win!"
+            return {
+                cProp: 1,
+>cProp : Symbol(cProp, Decl(derivedClassConstructorWithExplicitReturns01.ts, 24, 20))
+
+                dProp: () => this,
+>dProp : Symbol(dProp, Decl(derivedClassConstructorWithExplicitReturns01.ts, 25, 25))
+>this : Symbol(D, Decl(derivedClassConstructorWithExplicitReturns01.ts, 14, 1))
+
+                foo() { return "You win!!!!!" }
+>foo : Symbol(foo, Decl(derivedClassConstructorWithExplicitReturns01.ts, 26, 34))
+
+            };
+        }
+        else
+            return null;
+    }
+}
diff --git a/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.types b/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.types
new file mode 100644
index 00000000000..aa3b1ec7fbf
--- /dev/null
+++ b/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.types
@@ -0,0 +1,85 @@
+=== tests/cases/compiler/derivedClassConstructorWithExplicitReturns01.ts ===
+
+class C {
+>C : C
+
+    cProp = 10;
+>cProp : number
+>10 : number
+
+    foo() { return "this never gets used."; }
+>foo : () => string
+>"this never gets used." : string
+
+    constructor(value: number) {
+>value : number
+
+        return {
+>{            cProp: value,            foo() {                return "well this looks kinda C-ish.";            }        } : { cProp: number; foo(): string; }
+
+            cProp: value,
+>cProp : number
+>value : number
+
+            foo() {
+>foo : () => string
+
+                return "well this looks kinda C-ish.";
+>"well this looks kinda C-ish." : string
+            }
+        }
+    }
+}
+
+class D extends C {
+>D : D
+>C : C
+
+    dProp = () => this;
+>dProp : () => this
+>() => this : () => this
+>this : this
+
+    constructor(a = 100) {
+>a : number
+>100 : number
+
+        super(a);
+>super(a) : void
+>super : typeof C
+>a : number
+
+        if (Math.random() < 0.5) {
+>Math.random() < 0.5 : boolean
+>Math.random() : number
+>Math.random : () => number
+>Math : Math
+>random : () => number
+>0.5 : number
+
+            "You win!"
+>"You win!" : string
+
+            return {
+>{                cProp: 1,                dProp: () => this,                foo() { return "You win!!!!!" }            } : { cProp: number; dProp: () => this; foo(): string; }
+
+                cProp: 1,
+>cProp : number
+>1 : number
+
+                dProp: () => this,
+>dProp : () => this
+>() => this : () => this
+>this : this
+
+                foo() { return "You win!!!!!" }
+>foo : () => string
+>"You win!!!!!" : string
+
+            };
+        }
+        else
+            return null;
+>null : null
+    }
+}

From c87a773a462daba914c05fcb28617d632847a02c Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Sat, 3 Sep 2016 01:10:38 -0700
Subject: [PATCH 17/47] Don't emit a return statement at the end in most useful
 cases.

---
 src/compiler/transformers/es6.ts | 34 +++++++++++++++++++++++++++++++-
 1 file changed, 33 insertions(+), 1 deletion(-)

diff --git a/src/compiler/transformers/es6.ts b/src/compiler/transformers/es6.ts
index 44089326f7f..aa62af361db 100644
--- a/src/compiler/transformers/es6.ts
+++ b/src/compiler/transformers/es6.ts
@@ -804,7 +804,9 @@ namespace ts {
                 addRange(statements, body);
             }
 
-            if (extendsClauseElement) {
+            // Return `_this` unless we're sure enough that it would be pointless to add a return statement.
+            // If there's a constructor that we can tell returns in enough places, then we *do not* want to add a return.
+            if (extendsClauseElement && !(constructor && isSufficientlyCoveredByReturnStatements(constructor.body))) {
                 statements.push(
                     createReturn(
                         createIdentifier("_this")
@@ -833,6 +835,36 @@ namespace ts {
             return constructor => visitNodes(constructor.body.statements, visitor, isStatement, /*start*/ offset);
         }
 
+        /**
+         * We want to try to avoid emitting a return statement in certain cases if a user already returned something.
+         * It would be pointless and generate dead code, so we'll try to make things a little bit prettier
+         * by doing a minimal check on whether some common patterns always explicitly return.
+         */
+        function isSufficientlyCoveredByReturnStatements(statement: Statement): boolean {
+            // A return statement is considered covered.
+            if (statement.kind === SyntaxKind.ReturnStatement) {
+                return true;
+            }
+
+            // An if-statement with two covered branches is covered.
+            else if (statement.kind === SyntaxKind.IfStatement) {
+                const ifStatement = statement as IfStatement;
+                if (ifStatement.elseStatement) {
+                    return isSufficientlyCoveredByReturnStatements(ifStatement.thenStatement) &&
+                        isSufficientlyCoveredByReturnStatements(ifStatement.elseStatement);
+                }
+            }
+            // A block is covered if it has a last statement which is covered.
+            else if (statement.kind === SyntaxKind.Block) {
+                const lastStatement = lastOrUndefined((statement as Block).statements);
+                if (lastStatement && isSufficientlyCoveredByReturnStatements(lastStatement)) {
+                    return true;
+                }
+            }
+
+            return false;
+        }
+
         /**
          * Adds a synthesized call to `_super` if it is needed.
          *

From d144665b4f6637b8184725c74a7b60e894b81617 Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Sat, 3 Sep 2016 01:13:58 -0700
Subject: [PATCH 18/47] Accepted baselines.

---
 tests/baselines/reference/classExtendsNull.js |  2 --
 ...ctorFunctionTypeIsAssignableToBaseType2.js |  1 -
 ...edClassConstructorWithExplicitReturns01.js |  1 -
 ...assConstructorWithExplicitReturns01.js.map |  2 +-
 ...tructorWithExplicitReturns01.sourcemap.txt | 21 +++++++++----------
 .../reference/returnInConstructor1.js         |  2 --
 6 files changed, 11 insertions(+), 18 deletions(-)

diff --git a/tests/baselines/reference/classExtendsNull.js b/tests/baselines/reference/classExtendsNull.js
index a820b525aab..1eeb5172cad 100644
--- a/tests/baselines/reference/classExtendsNull.js
+++ b/tests/baselines/reference/classExtendsNull.js
@@ -23,7 +23,6 @@ var C = (function (_super) {
     function C() {
         var _this = _super.call(this) || this;
         return Object.create(null);
-        return _this;
     }
     return C;
 }(null));
@@ -32,7 +31,6 @@ var D = (function (_super) {
     function D() {
         var _this;
         return Object.create(null);
-        return _this;
     }
     return D;
 }(null));
diff --git a/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType2.js b/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType2.js
index 1ae239430c7..a60eb4de056 100644
--- a/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType2.js
+++ b/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType2.js
@@ -58,7 +58,6 @@ var Derived2 = (function (_super) {
     function Derived2(x) {
         var _this = _super.call(this, x) || this;
         return 1;
-        return _this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.js b/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.js
index de1e409b55f..4ab447d8e32 100644
--- a/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.js
+++ b/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.js
@@ -69,7 +69,6 @@ var D = (function (_super) {
         }
         else
             return null;
-        return _this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.js.map b/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.js.map
index dd7aedd1a98..8b9037e40c9 100644
--- a/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.js.map
+++ b/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.js.map
@@ -1,2 +1,2 @@
 //// [derivedClassConstructorWithExplicitReturns01.js.map]
-{"version":3,"file":"derivedClassConstructorWithExplicitReturns01.js","sourceRoot":"","sources":["derivedClassConstructorWithExplicitReturns01.ts"],"names":[],"mappings":";;;;;AACA;IAKI,WAAY,KAAa;QAJzB,UAAK,GAAG,EAAE,CAAC;QAKP,MAAM,CAAC;YACH,KAAK,EAAE,KAAK;YACZ,GAAG;gBACC,MAAM,CAAC,8BAA8B,CAAC;YAC1C,CAAC;SACJ,CAAA;IACL,CAAC;IATD,eAAG,GAAH,cAAQ,MAAM,CAAC,uBAAuB,CAAC,CAAC,CAAC;IAU7C,QAAC;AAAD,CAAC,AAbD,IAaC;AAED;IAAgB,qBAAC;IAGb,WAAY,CAAO;QAAP,kBAAA,EAAA,OAAO;QAAnB,YACI,kBAAM,CAAC,CAAC,SAYX;QAfD,WAAK,GAAG,cAAM,OAAA,KAAI,EAAJ,CAAI,CAAC;QAKf,EAAE,CAAC,CAAC,IAAI,CAAC,MAAM,EAAE,GAAG,GAAG,CAAC,CAAC,CAAC;YACtB,UAAU,CAAA;YACV,MAAM,CAAC;gBACH,KAAK,EAAE,CAAC;gBACR,KAAK,EAAE,cAAM,OAAA,KAAI,EAAJ,CAAI;gBACjB,GAAG,gBAAK,MAAM,CAAC,cAAc,CAAA,CAAC,CAAC;aAClC,CAAC;QACN,CAAC;QACD,IAAI;YACA,MAAM,CAAC,IAAI,CAAC;;IACpB,CAAC;IACL,QAAC;AAAD,CAAC,AAjBD,CAAgB,CAAC,GAiBhB"}
\ No newline at end of file
+{"version":3,"file":"derivedClassConstructorWithExplicitReturns01.js","sourceRoot":"","sources":["derivedClassConstructorWithExplicitReturns01.ts"],"names":[],"mappings":";;;;;AACA;IAKI,WAAY,KAAa;QAJzB,UAAK,GAAG,EAAE,CAAC;QAKP,MAAM,CAAC;YACH,KAAK,EAAE,KAAK;YACZ,GAAG;gBACC,MAAM,CAAC,8BAA8B,CAAC;YAC1C,CAAC;SACJ,CAAA;IACL,CAAC;IATD,eAAG,GAAH,cAAQ,MAAM,CAAC,uBAAuB,CAAC,CAAC,CAAC;IAU7C,QAAC;AAAD,CAAC,AAbD,IAaC;AAED;IAAgB,qBAAC;IAGb,WAAY,CAAO;QAAP,kBAAA,EAAA,OAAO;QAAnB,YACI,kBAAM,CAAC,CAAC,SAYX;QAfD,WAAK,GAAG,cAAM,OAAA,KAAI,EAAJ,CAAI,CAAC;QAKf,EAAE,CAAC,CAAC,IAAI,CAAC,MAAM,EAAE,GAAG,GAAG,CAAC,CAAC,CAAC;YACtB,UAAU,CAAA;YACV,MAAM,CAAC;gBACH,KAAK,EAAE,CAAC;gBACR,KAAK,EAAE,cAAM,OAAA,KAAI,EAAJ,CAAI;gBACjB,GAAG,gBAAK,MAAM,CAAC,cAAc,CAAA,CAAC,CAAC;aAClC,CAAC;QACN,CAAC;QACD,IAAI;YACA,MAAM,CAAC,IAAI,CAAC;IACpB,CAAC;IACL,QAAC;AAAD,CAAC,AAjBD,CAAgB,CAAC,GAiBhB"}
\ No newline at end of file
diff --git a/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.sourcemap.txt b/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.sourcemap.txt
index 5f41ab56300..d452115ceb7 100644
--- a/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.sourcemap.txt
+++ b/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.sourcemap.txt
@@ -522,7 +522,6 @@ sourceFile:derivedClassConstructorWithExplicitReturns01.ts
 4 >Emitted(34, 24) Source(32, 24) + SourceIndex(0)
 5 >Emitted(34, 25) Source(32, 25) + SourceIndex(0)
 ---
->>>        return _this;
 >>>    }
 1 >^^^^
 2 >    ^
@@ -530,8 +529,8 @@ sourceFile:derivedClassConstructorWithExplicitReturns01.ts
 1 >
   >    
 2 >    }
-1 >Emitted(36, 5) Source(33, 5) + SourceIndex(0)
-2 >Emitted(36, 6) Source(33, 6) + SourceIndex(0)
+1 >Emitted(35, 5) Source(33, 5) + SourceIndex(0)
+2 >Emitted(35, 6) Source(33, 6) + SourceIndex(0)
 ---
 >>>    return D;
 1->^^^^
@@ -539,8 +538,8 @@ sourceFile:derivedClassConstructorWithExplicitReturns01.ts
 1->
   >
 2 >    }
-1->Emitted(37, 5) Source(34, 1) + SourceIndex(0)
-2 >Emitted(37, 13) Source(34, 2) + SourceIndex(0)
+1->Emitted(36, 5) Source(34, 1) + SourceIndex(0)
+2 >Emitted(36, 13) Source(34, 2) + SourceIndex(0)
 ---
 >>>}(C));
 1 >
@@ -573,11 +572,11 @@ sourceFile:derivedClassConstructorWithExplicitReturns01.ts
   >               return null;
   >       }
   >   }
-1 >Emitted(38, 1) Source(34, 1) + SourceIndex(0)
-2 >Emitted(38, 2) Source(34, 2) + SourceIndex(0)
-3 >Emitted(38, 2) Source(17, 1) + SourceIndex(0)
-4 >Emitted(38, 3) Source(17, 17) + SourceIndex(0)
-5 >Emitted(38, 4) Source(17, 18) + SourceIndex(0)
-6 >Emitted(38, 7) Source(34, 2) + SourceIndex(0)
+1 >Emitted(37, 1) Source(34, 1) + SourceIndex(0)
+2 >Emitted(37, 2) Source(34, 2) + SourceIndex(0)
+3 >Emitted(37, 2) Source(17, 1) + SourceIndex(0)
+4 >Emitted(37, 3) Source(17, 17) + SourceIndex(0)
+5 >Emitted(37, 4) Source(17, 18) + SourceIndex(0)
+6 >Emitted(37, 7) Source(34, 2) + SourceIndex(0)
 ---
 >>>//# sourceMappingURL=derivedClassConstructorWithExplicitReturns01.js.map
\ No newline at end of file
diff --git a/tests/baselines/reference/returnInConstructor1.js b/tests/baselines/reference/returnInConstructor1.js
index 6c678db2358..a47fa7ed513 100644
--- a/tests/baselines/reference/returnInConstructor1.js
+++ b/tests/baselines/reference/returnInConstructor1.js
@@ -125,7 +125,6 @@ var H = (function (_super) {
     function H() {
         var _this = _super.call(this) || this;
         return new G(); //error
-        return _this;
     }
     return H;
 }(F));
@@ -134,7 +133,6 @@ var I = (function (_super) {
     function I() {
         var _this = _super.call(this) || this;
         return new G();
-        return _this;
     }
     return I;
 }(G));

From b476815f76eac2cbc3704fa91be5e22ef76fff8b Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Tue, 6 Sep 2016 11:31:20 -0700
Subject: [PATCH 19/47] Added test for '_this'.

---
 .../underscoreThisInDerivedClass01.ts         | 23 +++++++++++++++++++
 1 file changed, 23 insertions(+)
 create mode 100644 tests/cases/compiler/underscoreThisInDerivedClass01.ts

diff --git a/tests/cases/compiler/underscoreThisInDerivedClass01.ts b/tests/cases/compiler/underscoreThisInDerivedClass01.ts
new file mode 100644
index 00000000000..0d3f5849cb1
--- /dev/null
+++ b/tests/cases/compiler/underscoreThisInDerivedClass01.ts
@@ -0,0 +1,23 @@
+// @target es5
+
+// Original test intent:
+// When arrow functions capture 'this', the lexical 'this' owner
+// currently captures 'this' using a variable named '_this'.
+// That means that '_this' becomes a reserved identifier in certain places.
+//
+// Constructors have adopted the same identifier name ('_this')
+// for capturing any potential return values from super calls,
+// so we expect the same behavior.
+
+class C {
+    constructor() {
+        return {};
+    }
+}
+
+class D extends C {
+    constructor() {
+        var _this = "uh-oh?";
+        super();
+    }
+}
\ No newline at end of file

From 230737fb95db3af9d3c686328cbf5130f7529992 Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Tue, 6 Sep 2016 11:33:40 -0700
Subject: [PATCH 20/47] Accepted baselines.

---
 .../underscoreThisInDerivedClass01.js         | 56 +++++++++++++++++++
 .../underscoreThisInDerivedClass01.symbols    | 32 +++++++++++
 .../underscoreThisInDerivedClass01.types      | 35 ++++++++++++
 3 files changed, 123 insertions(+)
 create mode 100644 tests/baselines/reference/underscoreThisInDerivedClass01.js
 create mode 100644 tests/baselines/reference/underscoreThisInDerivedClass01.symbols
 create mode 100644 tests/baselines/reference/underscoreThisInDerivedClass01.types

diff --git a/tests/baselines/reference/underscoreThisInDerivedClass01.js b/tests/baselines/reference/underscoreThisInDerivedClass01.js
new file mode 100644
index 00000000000..000176c213f
--- /dev/null
+++ b/tests/baselines/reference/underscoreThisInDerivedClass01.js
@@ -0,0 +1,56 @@
+//// [underscoreThisInDerivedClass01.ts]
+// @target es5
+
+// Original test intent:
+// When arrow functions capture 'this', the lexical 'this' owner
+// currently captures 'this' using a variable named '_this'.
+// That means that '_this' becomes a reserved identifier in certain places.
+//
+// Constructors have adopted the same identifier name ('_this')
+// for capturing any potential return values from super calls,
+// so we expect the same behavior.
+
+class C {
+    constructor() {
+        return {};
+    }
+}
+
+class D extends C {
+    constructor() {
+        var _this = "uh-oh?";
+        super();
+    }
+}
+
+//// [underscoreThisInDerivedClass01.js]
+// @target es5
+var __extends = (this && this.__extends) || function (d, b) {
+    for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p];
+    function __() { this.constructor = d; }
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
+};
+// Original test intent:
+// When arrow functions capture 'this', the lexical 'this' owner
+// currently captures 'this' using a variable named '_this'.
+// That means that '_this' becomes a reserved identifier in certain places.
+//
+// Constructors have adopted the same identifier name ('_this')
+// for capturing any potential return values from super calls,
+// so we expect the same behavior.
+var C = (function () {
+    function C() {
+        return {};
+    }
+    return C;
+}());
+var D = (function (_super) {
+    __extends(D, _super);
+    function D() {
+        var _this;
+        var _this = "uh-oh?";
+        _this = _super.call(this) || this;
+        return _this;
+    }
+    return D;
+}(C));
diff --git a/tests/baselines/reference/underscoreThisInDerivedClass01.symbols b/tests/baselines/reference/underscoreThisInDerivedClass01.symbols
new file mode 100644
index 00000000000..c05cd4f6fc3
--- /dev/null
+++ b/tests/baselines/reference/underscoreThisInDerivedClass01.symbols
@@ -0,0 +1,32 @@
+=== tests/cases/compiler/underscoreThisInDerivedClass01.ts ===
+// @target es5
+
+// Original test intent:
+// When arrow functions capture 'this', the lexical 'this' owner
+// currently captures 'this' using a variable named '_this'.
+// That means that '_this' becomes a reserved identifier in certain places.
+//
+// Constructors have adopted the same identifier name ('_this')
+// for capturing any potential return values from super calls,
+// so we expect the same behavior.
+
+class C {
+>C : Symbol(C, Decl(underscoreThisInDerivedClass01.ts, 0, 0))
+
+    constructor() {
+        return {};
+    }
+}
+
+class D extends C {
+>D : Symbol(D, Decl(underscoreThisInDerivedClass01.ts, 15, 1))
+>C : Symbol(C, Decl(underscoreThisInDerivedClass01.ts, 0, 0))
+
+    constructor() {
+        var _this = "uh-oh?";
+>_this : Symbol(_this, Decl(underscoreThisInDerivedClass01.ts, 19, 11))
+
+        super();
+>super : Symbol(C, Decl(underscoreThisInDerivedClass01.ts, 0, 0))
+    }
+}
diff --git a/tests/baselines/reference/underscoreThisInDerivedClass01.types b/tests/baselines/reference/underscoreThisInDerivedClass01.types
new file mode 100644
index 00000000000..b07f3e0efbf
--- /dev/null
+++ b/tests/baselines/reference/underscoreThisInDerivedClass01.types
@@ -0,0 +1,35 @@
+=== tests/cases/compiler/underscoreThisInDerivedClass01.ts ===
+// @target es5
+
+// Original test intent:
+// When arrow functions capture 'this', the lexical 'this' owner
+// currently captures 'this' using a variable named '_this'.
+// That means that '_this' becomes a reserved identifier in certain places.
+//
+// Constructors have adopted the same identifier name ('_this')
+// for capturing any potential return values from super calls,
+// so we expect the same behavior.
+
+class C {
+>C : C
+
+    constructor() {
+        return {};
+>{} : {}
+    }
+}
+
+class D extends C {
+>D : D
+>C : C
+
+    constructor() {
+        var _this = "uh-oh?";
+>_this : string
+>"uh-oh?" : string
+
+        super();
+>super() : void
+>super : typeof C
+    }
+}

From b11db57c3209f75feca0f98473ec24296b039e29 Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Wed, 7 Sep 2016 12:23:06 -0700
Subject: [PATCH 21/47] Mark constructors as this-capturing if they are defined
 in a derived class.

---
 src/compiler/checker.ts   | 6 +++++-
 src/compiler/utilities.ts | 8 ++++----
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 81f22e2f192..9cb18f7c488 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -9215,14 +9215,18 @@ namespace ts {
             let container = getSuperContainer(node, /*stopOnFunctions*/ true);
             let needToCaptureLexicalThis = false;
 
+            // adjust the container reference in case if super is used inside arrow functions with arbitrarily deep nesting
             if (!isCallExpression) {
-                // adjust the container reference in case if super is used inside arrow functions with arbitrary deep nesting
                 while (container && container.kind === SyntaxKind.ArrowFunction) {
                     container = getSuperContainer(container, /*stopOnFunctions*/ true);
                     needToCaptureLexicalThis = languageVersion < ScriptTarget.ES6;
                 }
             }
 
+            if (languageVersion < ScriptTarget.ES6 && container && container.kind === SyntaxKind.Constructor) {
+                needToCaptureLexicalThis = needToCaptureLexicalThis || !!getClassExtendsHeritageClauseElement(getContainingClass(container));
+            }
+
             const canUseSuperExpression = isLegalUsageOfSuperExpression(container);
             let nodeCheckFlag: NodeCheckFlags = 0;
 
diff --git a/src/compiler/utilities.ts b/src/compiler/utilities.ts
index 030a3a33871..5d10c3c4c67 100644
--- a/src/compiler/utilities.ts
+++ b/src/compiler/utilities.ts
@@ -1032,11 +1032,11 @@ namespace ts {
     }
 
     /**
-      * Given an super call\property node returns a closest node where either
-      * - super call\property is legal in the node and not legal in the parent node the node.
+      * Given an super call/property node, returns the closest node where
+      * - a super call/property access is legal in the node and not legal in the parent node the node.
       *   i.e. super call is legal in constructor but not legal in the class body.
-      * - node is arrow function (so caller might need to call getSuperContainer in case it needs to climb higher)
-      * - super call\property is definitely illegal in the node (but might be legal in some subnode)
+      * - the container is an arrow function (so caller might need to call getSuperContainer again in case it needs to climb higher)
+      * - a super call/property is definitely illegal in the container (but might be legal in some subnode)
       *   i.e. super property access is illegal in function declaration but can be legal in the statement list
       */
     export function getSuperContainer(node: Node, stopOnFunctions: boolean): Node {

From 3a5fb0cec6e7db434a12043909bc12bc5866a5ec Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Wed, 7 Sep 2016 17:10:49 -0700
Subject: [PATCH 22/47] Accepted baselines.

---
 .../noImplicitAnyMissingGetAccessor.js        |  3 +-
 .../noImplicitAnyMissingSetAccessor.js        |  3 +-
 .../underscoreThisInDerivedClass01.errors.txt | 29 +++++++++++++++++++
 3 files changed, 33 insertions(+), 2 deletions(-)
 create mode 100644 tests/baselines/reference/underscoreThisInDerivedClass01.errors.txt

diff --git a/tests/baselines/reference/noImplicitAnyMissingGetAccessor.js b/tests/baselines/reference/noImplicitAnyMissingGetAccessor.js
index 69d98d4b0c6..d0e87aba25b 100644
--- a/tests/baselines/reference/noImplicitAnyMissingGetAccessor.js
+++ b/tests/baselines/reference/noImplicitAnyMissingGetAccessor.js
@@ -26,7 +26,8 @@ var Parent = (function () {
 var Child = (function (_super) {
     __extends(Child, _super);
     function Child() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Object.defineProperty(Child.prototype, "message", {
         set: function (str) {
diff --git a/tests/baselines/reference/noImplicitAnyMissingSetAccessor.js b/tests/baselines/reference/noImplicitAnyMissingSetAccessor.js
index 7ad703fd3b7..1b4119227bc 100644
--- a/tests/baselines/reference/noImplicitAnyMissingSetAccessor.js
+++ b/tests/baselines/reference/noImplicitAnyMissingSetAccessor.js
@@ -25,7 +25,8 @@ var Parent = (function () {
 var Child = (function (_super) {
     __extends(Child, _super);
     function Child() {
-        _super.apply(this, arguments);
+        var _this = _super.apply(this, arguments) || this;
+        return _this;
     }
     Object.defineProperty(Child.prototype, "message", {
         get: function () {
diff --git a/tests/baselines/reference/underscoreThisInDerivedClass01.errors.txt b/tests/baselines/reference/underscoreThisInDerivedClass01.errors.txt
new file mode 100644
index 00000000000..3828825cb6b
--- /dev/null
+++ b/tests/baselines/reference/underscoreThisInDerivedClass01.errors.txt
@@ -0,0 +1,29 @@
+tests/cases/compiler/underscoreThisInDerivedClass01.ts(20,13): error TS2399: Duplicate identifier '_this'. Compiler uses variable declaration '_this' to capture 'this' reference.
+
+
+==== tests/cases/compiler/underscoreThisInDerivedClass01.ts (1 errors) ====
+    // @target es5
+    
+    // Original test intent:
+    // When arrow functions capture 'this', the lexical 'this' owner
+    // currently captures 'this' using a variable named '_this'.
+    // That means that '_this' becomes a reserved identifier in certain places.
+    //
+    // Constructors have adopted the same identifier name ('_this')
+    // for capturing any potential return values from super calls,
+    // so we expect the same behavior.
+    
+    class C {
+        constructor() {
+            return {};
+        }
+    }
+    
+    class D extends C {
+        constructor() {
+            var _this = "uh-oh?";
+                ~~~~~
+!!! error TS2399: Duplicate identifier '_this'. Compiler uses variable declaration '_this' to capture 'this' reference.
+            super();
+        }
+    }
\ No newline at end of file

From f11c64648adb5f51decca90c2882d80ffbf93cf2 Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Wed, 7 Sep 2016 17:30:51 -0700
Subject: [PATCH 23/47] Added missing semicolons.

---
 src/compiler/transformers/es6.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/compiler/transformers/es6.ts b/src/compiler/transformers/es6.ts
index aa62af361db..a419170769b 100644
--- a/src/compiler/transformers/es6.ts
+++ b/src/compiler/transformers/es6.ts
@@ -2656,10 +2656,10 @@ namespace ts {
                     createLogicalOr(
                         resultingCall,
                         actualThis
-                    )
+                    );
                 return assignToCapturedThis
                     ? createAssignment(createIdentifier("_this"), initializer)
-                    : initializer
+                    : initializer;
             }
             return resultingCall;
         }

From 138e18c3c905c85b13a16e85f7f69e5c3a4d9e3e Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Mon, 19 Sep 2016 18:30:35 +0300
Subject: [PATCH 24/47] Accepted baselines.

---
 ...edClassConstructorWithExplicitReturns01.types | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.types b/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.types
index aa3b1ec7fbf..d361e783ef0 100644
--- a/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.types
+++ b/tests/baselines/reference/derivedClassConstructorWithExplicitReturns01.types
@@ -5,11 +5,11 @@ class C {
 
     cProp = 10;
 >cProp : number
->10 : number
+>10 : 10
 
     foo() { return "this never gets used."; }
 >foo : () => string
->"this never gets used." : string
+>"this never gets used." : "this never gets used."
 
     constructor(value: number) {
 >value : number
@@ -25,7 +25,7 @@ class C {
 >foo : () => string
 
                 return "well this looks kinda C-ish.";
->"well this looks kinda C-ish." : string
+>"well this looks kinda C-ish." : "well this looks kinda C-ish."
             }
         }
     }
@@ -42,7 +42,7 @@ class D extends C {
 
     constructor(a = 100) {
 >a : number
->100 : number
+>100 : 100
 
         super(a);
 >super(a) : void
@@ -55,17 +55,17 @@ class D extends C {
 >Math.random : () => number
 >Math : Math
 >random : () => number
->0.5 : number
+>0.5 : 0.5
 
             "You win!"
->"You win!" : string
+>"You win!" : "You win!"
 
             return {
 >{                cProp: 1,                dProp: () => this,                foo() { return "You win!!!!!" }            } : { cProp: number; dProp: () => this; foo(): string; }
 
                 cProp: 1,
 >cProp : number
->1 : number
+>1 : 1
 
                 dProp: () => this,
 >dProp : () => this
@@ -74,7 +74,7 @@ class D extends C {
 
                 foo() { return "You win!!!!!" }
 >foo : () => string
->"You win!!!!!" : string
+>"You win!!!!!" : "You win!!!!!"
 
             };
         }

From da298132048f58942a809561325a4bdd1d965aa1 Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Mon, 19 Sep 2016 18:01:32 +0300
Subject: [PATCH 25/47] Added test and comment.

---
 src/compiler/checker.ts                         |  1 +
 .../compiler/underscoreThisInDerivedClass02.ts  | 17 +++++++++++++++++
 2 files changed, 18 insertions(+)
 create mode 100644 tests/cases/compiler/underscoreThisInDerivedClass02.ts

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 7d007950c93..20fb56870da 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -9322,6 +9322,7 @@ namespace ts {
                 }
             }
 
+            // Even if 'super' isn't ever actually called, we may need to capture 'this' for a derived class.
             if (languageVersion < ScriptTarget.ES6 && container && container.kind === SyntaxKind.Constructor) {
                 needToCaptureLexicalThis = needToCaptureLexicalThis || !!getClassExtendsHeritageClauseElement(getContainingClass(container));
             }
diff --git a/tests/cases/compiler/underscoreThisInDerivedClass02.ts b/tests/cases/compiler/underscoreThisInDerivedClass02.ts
new file mode 100644
index 00000000000..da197258a73
--- /dev/null
+++ b/tests/cases/compiler/underscoreThisInDerivedClass02.ts
@@ -0,0 +1,17 @@
+// @target es5
+
+// Original test intent:
+// Errors on '_this' should be reported in derived constructors,
+// even if 'super()' is not called.
+
+class C {
+    constructor() {
+        return {};
+    }
+}
+
+class D extends C {
+    constructor() {
+        var _this = "uh-oh?";
+    }
+}
\ No newline at end of file

From 60bcd7e0d009090170a7fa48580359cfb14e80c7 Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Mon, 19 Sep 2016 18:05:34 +0300
Subject: [PATCH 26/47] Accepted baselines.

---
 .../underscoreThisInDerivedClass02.errors.txt | 25 +++++++++++
 .../underscoreThisInDerivedClass02.js         | 44 +++++++++++++++++++
 2 files changed, 69 insertions(+)
 create mode 100644 tests/baselines/reference/underscoreThisInDerivedClass02.errors.txt
 create mode 100644 tests/baselines/reference/underscoreThisInDerivedClass02.js

diff --git a/tests/baselines/reference/underscoreThisInDerivedClass02.errors.txt b/tests/baselines/reference/underscoreThisInDerivedClass02.errors.txt
new file mode 100644
index 00000000000..f7e0494c884
--- /dev/null
+++ b/tests/baselines/reference/underscoreThisInDerivedClass02.errors.txt
@@ -0,0 +1,25 @@
+tests/cases/compiler/underscoreThisInDerivedClass02.ts(14,5): error TS2377: Constructors for derived classes must contain a 'super' call.
+
+
+==== tests/cases/compiler/underscoreThisInDerivedClass02.ts (1 errors) ====
+    // @target es5
+    
+    // Original test intent:
+    // Errors on '_this' should be reported in derived constructors,
+    // even if 'super()' is not called.
+    
+    class C {
+        constructor() {
+            return {};
+        }
+    }
+    
+    class D extends C {
+        constructor() {
+        ~~~~~~~~~~~~~~~
+            var _this = "uh-oh?";
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+        }
+    ~~~~~
+!!! error TS2377: Constructors for derived classes must contain a 'super' call.
+    }
\ No newline at end of file
diff --git a/tests/baselines/reference/underscoreThisInDerivedClass02.js b/tests/baselines/reference/underscoreThisInDerivedClass02.js
new file mode 100644
index 00000000000..c1e9494376b
--- /dev/null
+++ b/tests/baselines/reference/underscoreThisInDerivedClass02.js
@@ -0,0 +1,44 @@
+//// [underscoreThisInDerivedClass02.ts]
+// @target es5
+
+// Original test intent:
+// Errors on '_this' should be reported in derived constructors,
+// even if 'super()' is not called.
+
+class C {
+    constructor() {
+        return {};
+    }
+}
+
+class D extends C {
+    constructor() {
+        var _this = "uh-oh?";
+    }
+}
+
+//// [underscoreThisInDerivedClass02.js]
+// @target es5
+var __extends = (this && this.__extends) || function (d, b) {
+    for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p];
+    function __() { this.constructor = d; }
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
+};
+// Original test intent:
+// Errors on '_this' should be reported in derived constructors,
+// even if 'super()' is not called.
+var C = (function () {
+    function C() {
+        return {};
+    }
+    return C;
+}());
+var D = (function (_super) {
+    __extends(D, _super);
+    function D() {
+        var _this;
+        var _this = "uh-oh?";
+        return _this;
+    }
+    return D;
+}(C));

From 5b3a93db2fca4f8197dee1b979a3e22b282da697 Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Mon, 19 Sep 2016 18:29:15 +0300
Subject: [PATCH 27/47] Always mark derived constructors as 'this'-capturing.

---
 src/compiler/checker.ts | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 20fb56870da..29270628fb0 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -9322,11 +9322,6 @@ namespace ts {
                 }
             }
 
-            // Even if 'super' isn't ever actually called, we may need to capture 'this' for a derived class.
-            if (languageVersion < ScriptTarget.ES6 && container && container.kind === SyntaxKind.Constructor) {
-                needToCaptureLexicalThis = needToCaptureLexicalThis || !!getClassExtendsHeritageClauseElement(getContainingClass(container));
-            }
-
             const canUseSuperExpression = isLegalUsageOfSuperExpression(container);
             let nodeCheckFlag: NodeCheckFlags = 0;
 
@@ -14312,6 +14307,7 @@ namespace ts {
             // constructors of derived classes must contain at least one super call somewhere in their function body.
             const containingClassDecl = <ClassDeclaration>node.parent;
             if (getClassExtendsHeritageClauseElement(containingClassDecl)) {
+                captureLexicalThis(node.parent, containingClassDecl);
                 const classExtendsNull = classDeclarationExtendsNull(containingClassDecl);
                 const superCall = getSuperCallInConstructor(node);
                 if (superCall) {

From bc4cf6d3c06a7dbb6d5bffa728de163788c3d83f Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Mon, 19 Sep 2016 18:30:15 +0300
Subject: [PATCH 28/47] Accepted baselines.

---
 .../reference/underscoreThisInDerivedClass02.errors.txt      | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/tests/baselines/reference/underscoreThisInDerivedClass02.errors.txt b/tests/baselines/reference/underscoreThisInDerivedClass02.errors.txt
index f7e0494c884..5569ebf1af6 100644
--- a/tests/baselines/reference/underscoreThisInDerivedClass02.errors.txt
+++ b/tests/baselines/reference/underscoreThisInDerivedClass02.errors.txt
@@ -1,7 +1,8 @@
 tests/cases/compiler/underscoreThisInDerivedClass02.ts(14,5): error TS2377: Constructors for derived classes must contain a 'super' call.
+tests/cases/compiler/underscoreThisInDerivedClass02.ts(15,13): error TS2399: Duplicate identifier '_this'. Compiler uses variable declaration '_this' to capture 'this' reference.
 
 
-==== tests/cases/compiler/underscoreThisInDerivedClass02.ts (1 errors) ====
+==== tests/cases/compiler/underscoreThisInDerivedClass02.ts (2 errors) ====
     // @target es5
     
     // Original test intent:
@@ -19,6 +20,8 @@ tests/cases/compiler/underscoreThisInDerivedClass02.ts(14,5): error TS2377: Cons
         ~~~~~~~~~~~~~~~
             var _this = "uh-oh?";
     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+                ~~~~~
+!!! error TS2399: Duplicate identifier '_this'. Compiler uses variable declaration '_this' to capture 'this' reference.
         }
     ~~~~~
 !!! error TS2377: Constructors for derived classes must contain a 'super' call.

From dc58fb5558a29794cea65b0c5e6e684f2354a75e Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Tue, 20 Sep 2016 12:29:13 -0400
Subject: [PATCH 29/47] Immediately return the result of super calls when they
 are the first & last statement in a constructor.

---
 src/compiler/transformers/es6.ts | 123 +++++++++++++++++++++----------
 1 file changed, 85 insertions(+), 38 deletions(-)

diff --git a/src/compiler/transformers/es6.ts b/src/compiler/transformers/es6.ts
index 535e9162a3a..5748739cb23 100644
--- a/src/compiler/transformers/es6.ts
+++ b/src/compiler/transformers/es6.ts
@@ -139,6 +139,30 @@ namespace ts {
         loopOutParameters?: LoopOutParameter[];
     }
 
+    const enum SuperCaptureResult {
+        /**
+         * A capture may have been added for calls to 'super', but
+         * the caller should emit subsequent statements normally.
+         */
+        NoReplacement,
+        /**
+         * A call to 'super()' got replaced with a capturing statement like:
+         *
+         *  var _this = _super.call(...) || this;
+         *
+         * Callers should skip the current statement.
+         */
+        ReplaceSuperCapture,
+        /**
+         * A call to 'super()' got replaced with a capturing statement like:
+         *
+         *  return _super.call(...) || this;
+         *
+         * Callers should skip the current statement and avoid any returns of '_this'.
+         */
+        ReplaceWithReturn,
+}
+
     export function transformES6(context: TransformationContext) {
         const {
             startLexicalEnvironment,
@@ -814,6 +838,7 @@ namespace ts {
             startLexicalEnvironment();
 
             let statementOffset = -1;
+            let thisCaptureStatus: SuperCaptureResult | undefined;
             if (hasSynthesizedSuper) {
                 // If a super call has already been synthesized,
                 // we're going to assume that we should just transform everything after that.
@@ -829,7 +854,11 @@ namespace ts {
                 addDefaultValueAssignmentsIfNeeded(statements, constructor);
                 addRestParameterIfNeeded(statements, constructor, hasSynthesizedSuper);
                 Debug.assert(statementOffset >= 0, "statementOffset not initialized correctly!");
-                statementOffset = declareOrCaptureThisForConstructorIfNeeded(statements, constructor, !!extendsClauseElement, statementOffset);
+
+                thisCaptureStatus = declareOrCaptureOrReturnThisForConstructorIfNeeded(statements, constructor, !!extendsClauseElement, statementOffset);
+                if (thisCaptureStatus === SuperCaptureResult.ReplaceSuperCapture || thisCaptureStatus === SuperCaptureResult.ReplaceWithReturn) {
+                    statementOffset++;
+                }
             }
 
             addDefaultSuperCallIfNeeded(statements, constructor, extendsClauseElement, hasSynthesizedSuper);
@@ -841,7 +870,9 @@ namespace ts {
 
             // Return `_this` unless we're sure enough that it would be pointless to add a return statement.
             // If there's a constructor that we can tell returns in enough places, then we *do not* want to add a return.
-            if (extendsClauseElement && !(constructor && isSufficientlyCoveredByReturnStatements(constructor.body))) {
+            if (extendsClauseElement
+                && thisCaptureStatus !== SuperCaptureResult.ReplaceWithReturn
+                && !(constructor && isSufficientlyCoveredByReturnStatements(constructor.body))) {
                 statements.push(
                     createReturn(
                         createIdentifier("_this")
@@ -1190,45 +1221,61 @@ namespace ts {
          *
          * @returns The new statement offset into the `statements` array.
          */
-        function declareOrCaptureThisForConstructorIfNeeded(statements: Statement[], ctor: ConstructorDeclaration, hasExtendsClause: boolean, firstNonPrologue: number) {
-            if (hasExtendsClause) {
-                // Most of the time, a 'super' call will be the first real statement in a constructor body.
-                // In these cases, we'd like to transform these into a *single* statement instead of a declaration
-                // followed by an assignment statement for '_this'. For instance, if we emitted without an initializer,
-                // we'd get:
-                //
-                //      var _this;
-                //      _this = super();
-                //
-                // instead of
-                //
-                //      var _this = super();
-                //
-                let initializer: Expression = undefined;
-                let firstStatement: Statement;
-                if (firstNonPrologue < ctor.body.statements.length) {
-                    firstStatement = ctor.body.statements[firstNonPrologue];
-
-                    if (firstStatement.kind === SyntaxKind.ExpressionStatement && isSuperCallExpression((firstStatement as ExpressionStatement).expression)) {
-                        const superCall = (firstStatement as ExpressionStatement).expression as CallExpression;
-                        initializer = setOriginalNode(
-                            saveStateAndInvoke(superCall, visitImmediateSuperCallInBody),
-                            superCall
-                        );
-                    }
-                }
-                captureThisForNode(statements, ctor, /*initializer*/ initializer, firstStatement);
-
-                // We're actually skipping an extra statement. Signal this to the caller.
-                if (initializer) {
-                    return firstNonPrologue + 1;
-                }
-            }
-            else {
+        function declareOrCaptureOrReturnThisForConstructorIfNeeded(statements: Statement[], ctor: ConstructorDeclaration, hasExtendsClause: boolean, statementOffset: number) {
+            // If this isn't a derived class, just capture 'this' for arrow functions if necessary.
+            if (!hasExtendsClause) {
                 addCaptureThisForNodeIfNeeded(statements, ctor);
+                return SuperCaptureResult.NoReplacement;
             }
 
-            return firstNonPrologue;
+            // Most of the time, a 'super' call will be the first real statement in a constructor body.
+            // In these cases, we'd like to transform these into a *single* statement instead of a declaration
+            // followed by an assignment statement for '_this'. For instance, if we emitted without an initializer,
+            // we'd get:
+            //
+            //      var _this;
+            //      _this = _super.call(...) || this;
+            //
+            // instead of
+            //
+            //      var _this = _super.call(...) || this;
+            //
+            // Additionally, if the 'super()' call is the last statement, we should just avoid capturing
+            // entirely and immediately return the result like so:
+            //
+            //      return _super.call(...) || this;
+            //
+            let firstStatement: Statement;
+            let superCallExpression: Expression;
+
+            const ctorStatements = ctor.body.statements;
+            if (statementOffset < ctorStatements.length) {
+                firstStatement = ctorStatements[statementOffset];
+
+                if (firstStatement.kind === SyntaxKind.ExpressionStatement && isSuperCallExpression((firstStatement as ExpressionStatement).expression)) {
+                    const superCall = (firstStatement as ExpressionStatement).expression as CallExpression;
+                    superCallExpression = setOriginalNode(
+                        saveStateAndInvoke(superCall, visitImmediateSuperCallInBody),
+                        superCall
+                    );
+                }
+            }
+
+            // Return the result if we have an immediate super() call on the last statement.
+            if (superCallExpression && statementOffset === ctorStatements.length - 1) {
+                statements.push(createReturn(superCallExpression));
+                return SuperCaptureResult.ReplaceWithReturn;
+            }
+
+            // Perform the capture.
+            captureThisForNode(statements, ctor, superCallExpression, firstStatement);
+
+            // If we're actually replacing the original statement, we need to signal this to the caller.
+            if (superCallExpression) {
+                return SuperCaptureResult.ReplaceSuperCapture;
+            }
+
+            return SuperCaptureResult.NoReplacement;
         }
 
         /**

From cd787cc1c2effa78d5877dd7d642e03a9d2484c3 Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Tue, 20 Sep 2016 12:29:32 -0400
Subject: [PATCH 30/47] Accepted baselines.

---
 .../reference/arrowFunctionContexts.js        |  6 ++--
 tests/baselines/reference/baseCheck.js        |  6 ++--
 .../reference/captureThisInSuperCall.js       |  3 +-
 .../reference/checkForObjectTooStrict.js      |  6 ++--
 .../checkSuperCallBeforeThisAccessing5.js     |  3 +-
 .../checkSuperCallBeforeThisAccessing7.js     |  3 +-
 .../reference/classSideInheritance2.js        |  3 +-
 .../reference/classSideInheritance3.js        |  3 +-
 tests/baselines/reference/classUpdateTests.js |  3 +-
 .../reference/collisionSuperAndParameter.js   |  3 +-
 ...perAndPropertyNameAsConstuctorParameter.js |  6 ++--
 .../reference/commentsInheritance.js          |  3 +-
 ...ctorFunctionTypeIsAssignableToBaseType2.js |  3 +-
 .../reference/constructorOverloads2.js        |  3 +-
 .../reference/declFileGenericType2.js         |  3 +-
 .../reference/decoratorOnClassConstructor2.js |  3 +-
 .../reference/decoratorOnClassConstructor3.js |  3 +-
 .../derivedClassOverridesPrivateFunction1.js  |  3 +-
 .../derivedClassOverridesProtectedMembers.js  |  3 +-
 .../derivedClassOverridesProtectedMembers2.js |  3 +-
 .../derivedClassOverridesProtectedMembers3.js | 30 +++++++------------
 .../derivedClassOverridesPublicMembers.js     |  3 +-
 .../derivedClassSuperCallsWithThisArg.js      |  3 +-
 .../destructuringParameterDeclaration5.js     |  6 ++--
 tests/baselines/reference/es6ClassTest2.js    |  3 +-
 ...cClassPropertyInheritanceSpecialization.js |  3 +-
 ...genericConstraintOnExtendedBuiltinTypes.js |  3 +-
 ...enericConstraintOnExtendedBuiltinTypes2.js |  3 +-
 .../reference/genericTypeConstraints.js       |  3 +-
 .../missingPropertiesOfClassExpression.js     |  3 +-
 .../reference/optionalParamArgsTest.js        |  3 +-
 .../baselines/reference/parserRealSource11.js | 21 +++++--------
 tests/baselines/reference/parserharness.js    |  3 +-
 .../reference/strictModeInConstructor.js      |  3 +-
 .../superCallBeforeThisAccessing2.js          |  3 +-
 .../superCallBeforeThisAccessing6.js          |  3 +-
 ...allFromClassThatDerivesFromGenericType1.js |  3 +-
 ...allFromClassThatDerivesFromGenericType2.js |  3 +-
 ...eButWithIncorrectNumberOfTypeArguments1.js |  3 +-
 ...sFromGenericTypeButWithNoTypeArguments1.js |  3 +-
 ...ivesNonGenericTypeButWithTypeArguments1.js |  3 +-
 .../superCallInsideClassDeclaration.js        |  3 +-
 .../superCallInsideClassExpression.js         |  3 +-
 .../superCallParameterContextualTyping1.js    |  3 +-
 .../superCallParameterContextualTyping2.js    |  3 +-
 .../superWithGenericSpecialization.js         |  3 +-
 .../baselines/reference/superWithGenerics.js  |  3 +-
 .../reference/targetTypeBaseCalls.js          |  3 +-
 .../reference/thisInInvalidContexts.js        |  3 +-
 .../thisInInvalidContextsExternalModule.js    |  3 +-
 tests/baselines/reference/thisInSuperCall.js  |  3 +-
 tests/baselines/reference/thisInSuperCall2.js |  3 +-
 tests/baselines/reference/unknownSymbols1.js  |  3 +-
 .../reference/validUseOfThisInSuper.js        |  3 +-
 54 files changed, 74 insertions(+), 148 deletions(-)

diff --git a/tests/baselines/reference/arrowFunctionContexts.js b/tests/baselines/reference/arrowFunctionContexts.js
index 1af0797b41f..64727398f72 100644
--- a/tests/baselines/reference/arrowFunctionContexts.js
+++ b/tests/baselines/reference/arrowFunctionContexts.js
@@ -116,8 +116,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.call(this, function () { return _this; }) || this;
-        return _this;
+        return _super.call(this, function () { return _this; }) || this;
     }
     return Derived;
 }(Base));
@@ -158,8 +157,7 @@ var M2;
     var Derived = (function (_super) {
         __extends(Derived, _super);
         function Derived() {
-            var _this = _super.call(this, function () { return _this; }) || this;
-            return _this;
+            return _super.call(this, function () { return _this; }) || this;
         }
         return Derived;
     }(Base));
diff --git a/tests/baselines/reference/baseCheck.js b/tests/baselines/reference/baseCheck.js
index 623cd152b9a..870f811c09f 100644
--- a/tests/baselines/reference/baseCheck.js
+++ b/tests/baselines/reference/baseCheck.js
@@ -43,16 +43,14 @@ var C = (function () {
 var ELoc = (function (_super) {
     __extends(ELoc, _super);
     function ELoc(x) {
-        var _this = _super.call(this, 0, x) || this;
-        return _this;
+        return _super.call(this, 0, x) || this;
     }
     return ELoc;
 }(C));
 var ELocVar = (function (_super) {
     __extends(ELocVar, _super);
     function ELocVar(x) {
-        var _this = _super.call(this, 0, loc) || this;
-        return _this;
+        return _super.call(this, 0, loc) || this;
     }
     ELocVar.prototype.m = function () {
         var loc = 10;
diff --git a/tests/baselines/reference/captureThisInSuperCall.js b/tests/baselines/reference/captureThisInSuperCall.js
index 069871f598e..2c4df5db961 100644
--- a/tests/baselines/reference/captureThisInSuperCall.js
+++ b/tests/baselines/reference/captureThisInSuperCall.js
@@ -22,8 +22,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.call(this, { test: function () { return _this.someMethod(); } }) || this;
-        return _this;
+        return _super.call(this, { test: function () { return _this.someMethod(); } }) || this;
     }
     B.prototype.someMethod = function () { };
     return B;
diff --git a/tests/baselines/reference/checkForObjectTooStrict.js b/tests/baselines/reference/checkForObjectTooStrict.js
index 156608bd6b5..ade99e9319b 100644
--- a/tests/baselines/reference/checkForObjectTooStrict.js
+++ b/tests/baselines/reference/checkForObjectTooStrict.js
@@ -49,16 +49,14 @@ var Foo;
 var Bar = (function (_super) {
     __extends(Bar, _super);
     function Bar() {
-        var _this = _super.call(this) || this;
-        return _this;
+        return _super.call(this) || this;
     }
     return Bar;
 }(Foo.Object));
 var Baz = (function (_super) {
     __extends(Baz, _super);
     function Baz() {
-        var _this = _super.call(this) || this;
-        return _this;
+        return _super.call(this) || this;
     }
     return Baz;
 }(Object));
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing5.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing5.js
index 3174bebd11d..8c7f18b77f6 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing5.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing5.js
@@ -25,8 +25,7 @@ var Based = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.call(this, _this.x) || this;
-        return _this;
+        return _super.call(this, this.x) || this;
     }
     return Derived;
 }(Based));
diff --git a/tests/baselines/reference/checkSuperCallBeforeThisAccessing7.js b/tests/baselines/reference/checkSuperCallBeforeThisAccessing7.js
index 364aed4d4b0..ca12c16e047 100644
--- a/tests/baselines/reference/checkSuperCallBeforeThisAccessing7.js
+++ b/tests/baselines/reference/checkSuperCallBeforeThisAccessing7.js
@@ -23,8 +23,7 @@ var Base = (function () {
 var Super = (function (_super) {
     __extends(Super, _super);
     function Super() {
-        var _this = _super.call(this, (function () { return _this; })) || this;
-        return _this;
+        return _super.call(this, (function () { return _this; })) || this;
     }
     return Super;
 }(Base));
diff --git a/tests/baselines/reference/classSideInheritance2.js b/tests/baselines/reference/classSideInheritance2.js
index 475f9bd4ceb..67ee666749b 100644
--- a/tests/baselines/reference/classSideInheritance2.js
+++ b/tests/baselines/reference/classSideInheritance2.js
@@ -29,8 +29,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var SubText = (function (_super) {
     __extends(SubText, _super);
     function SubText(text, span) {
-        var _this = _super.call(this) || this;
-        return _this;
+        return _super.call(this) || this;
     }
     return SubText;
 }(TextBase));
diff --git a/tests/baselines/reference/classSideInheritance3.js b/tests/baselines/reference/classSideInheritance3.js
index 361378c3ff5..589dd81c5c6 100644
--- a/tests/baselines/reference/classSideInheritance3.js
+++ b/tests/baselines/reference/classSideInheritance3.js
@@ -42,8 +42,7 @@ var B = (function (_super) {
 var C = (function (_super) {
     __extends(C, _super);
     function C(x) {
-        var _this = _super.call(this, x) || this;
-        return _this;
+        return _super.call(this, x) || this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/classUpdateTests.js b/tests/baselines/reference/classUpdateTests.js
index 9809966c4c2..53ef71d0e4b 100644
--- a/tests/baselines/reference/classUpdateTests.js
+++ b/tests/baselines/reference/classUpdateTests.js
@@ -189,8 +189,7 @@ var H = (function () {
 var I = (function (_super) {
     __extends(I, _super);
     function I() {
-        var _this = _super.call(this) || this;
-        return _this;
+        return _super.call(this) || this;
     } // ERROR - no super call allowed
     return I;
 }(Object));
diff --git a/tests/baselines/reference/collisionSuperAndParameter.js b/tests/baselines/reference/collisionSuperAndParameter.js
index 750ae15ef0a..f5765043c55 100644
--- a/tests/baselines/reference/collisionSuperAndParameter.js
+++ b/tests/baselines/reference/collisionSuperAndParameter.js
@@ -124,8 +124,7 @@ var Foo2 = (function (_super) {
 var Foo4 = (function (_super) {
     __extends(Foo4, _super);
     function Foo4(_super) {
-        var _this = _super.call(this) || this;
-        return _this;
+        return _super.call(this) || this;
     }
     Foo4.prototype.y = function (_super) {
         var _this = this;
diff --git a/tests/baselines/reference/collisionSuperAndPropertyNameAsConstuctorParameter.js b/tests/baselines/reference/collisionSuperAndPropertyNameAsConstuctorParameter.js
index 269881b3b90..5fa7fe29091 100644
--- a/tests/baselines/reference/collisionSuperAndPropertyNameAsConstuctorParameter.js
+++ b/tests/baselines/reference/collisionSuperAndPropertyNameAsConstuctorParameter.js
@@ -44,8 +44,7 @@ var a = (function () {
 var b1 = (function (_super) {
     __extends(b1, _super);
     function b1(_super) {
-        var _this = _super.call(this) || this;
-        return _this;
+        return _super.call(this) || this;
     }
     return b1;
 }(a));
@@ -61,8 +60,7 @@ var b2 = (function (_super) {
 var b3 = (function (_super) {
     __extends(b3, _super);
     function b3(_super) {
-        var _this = _super.call(this) || this;
-        return _this;
+        return _super.call(this) || this;
     }
     return b3;
 }(a));
diff --git a/tests/baselines/reference/commentsInheritance.js b/tests/baselines/reference/commentsInheritance.js
index 294f3a33690..a8a8d5fa889 100644
--- a/tests/baselines/reference/commentsInheritance.js
+++ b/tests/baselines/reference/commentsInheritance.js
@@ -227,8 +227,7 @@ var c2 = (function () {
 var c3 = (function (_super) {
     __extends(c3, _super);
     function c3() {
-        var _this = _super.call(this, 10) || this;
-        return _this;
+        return _super.call(this, 10) || this;
     }
     /** c3 f1*/
     c3.prototype.f1 = function () {
diff --git a/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType2.js b/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType2.js
index a60eb4de056..c5e27748f52 100644
--- a/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType2.js
+++ b/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType2.js
@@ -47,8 +47,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived(x) {
-        var _this = _super.call(this, x) || this;
-        return _this;
+        return _super.call(this, x) || this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/constructorOverloads2.js b/tests/baselines/reference/constructorOverloads2.js
index c26d031656f..2d26194f2e7 100644
--- a/tests/baselines/reference/constructorOverloads2.js
+++ b/tests/baselines/reference/constructorOverloads2.js
@@ -40,8 +40,7 @@ var FooBase = (function () {
 var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo(x, y) {
-        var _this = _super.call(this, x) || this;
-        return _this;
+        return _super.call(this, x) || this;
     }
     Foo.prototype.bar1 = function () { };
     return Foo;
diff --git a/tests/baselines/reference/declFileGenericType2.js b/tests/baselines/reference/declFileGenericType2.js
index 328ab0cd949..a51254122ed 100644
--- a/tests/baselines/reference/declFileGenericType2.js
+++ b/tests/baselines/reference/declFileGenericType2.js
@@ -58,8 +58,7 @@ var templa;
             var AbstractElementController = (function (_super) {
                 __extends(AbstractElementController, _super);
                 function AbstractElementController() {
-                    var _this = _super.call(this) || this;
-                    return _this;
+                    return _super.call(this) || this;
                 }
                 return AbstractElementController;
             }(templa.mvc.AbstractController));
diff --git a/tests/baselines/reference/decoratorOnClassConstructor2.js b/tests/baselines/reference/decoratorOnClassConstructor2.js
index 44bde0a171d..ce323e8ed1e 100644
--- a/tests/baselines/reference/decoratorOnClassConstructor2.js
+++ b/tests/baselines/reference/decoratorOnClassConstructor2.js
@@ -45,8 +45,7 @@ var _0_ts_2 = require("./0.ts");
 var C = (function (_super) {
     __extends(C, _super);
     function C(prop) {
-        var _this = _super.call(this) || this;
-        return _this;
+        return _super.call(this) || this;
     }
     return C;
 }(_0_ts_1.base));
diff --git a/tests/baselines/reference/decoratorOnClassConstructor3.js b/tests/baselines/reference/decoratorOnClassConstructor3.js
index 5130986b1f7..f06bf80b21d 100644
--- a/tests/baselines/reference/decoratorOnClassConstructor3.js
+++ b/tests/baselines/reference/decoratorOnClassConstructor3.js
@@ -48,8 +48,7 @@ var _0_2 = require("./0");
 var C = (function (_super) {
     __extends(C, _super);
     function C(prop) {
-        var _this = _super.call(this) || this;
-        return _this;
+        return _super.call(this) || this;
     }
     return C;
 }(_0_1.base));
diff --git a/tests/baselines/reference/derivedClassOverridesPrivateFunction1.js b/tests/baselines/reference/derivedClassOverridesPrivateFunction1.js
index a0b1559d430..981c072d47c 100644
--- a/tests/baselines/reference/derivedClassOverridesPrivateFunction1.js
+++ b/tests/baselines/reference/derivedClassOverridesPrivateFunction1.js
@@ -32,8 +32,7 @@ var BaseClass = (function () {
 var DerivedClass = (function (_super) {
     __extends(DerivedClass, _super);
     function DerivedClass() {
-        var _this = _super.call(this) || this;
-        return _this;
+        return _super.call(this) || this;
     }
     DerivedClass.prototype._init = function () {
     };
diff --git a/tests/baselines/reference/derivedClassOverridesProtectedMembers.js b/tests/baselines/reference/derivedClassOverridesProtectedMembers.js
index e86806d31d2..b8997769eb7 100644
--- a/tests/baselines/reference/derivedClassOverridesProtectedMembers.js
+++ b/tests/baselines/reference/derivedClassOverridesProtectedMembers.js
@@ -66,8 +66,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived(a) {
-        var _this = _super.call(this, x) || this;
-        return _this;
+        return _super.call(this, x) || this;
     }
     Derived.prototype.b = function (a) { };
     Object.defineProperty(Derived.prototype, "c", {
diff --git a/tests/baselines/reference/derivedClassOverridesProtectedMembers2.js b/tests/baselines/reference/derivedClassOverridesProtectedMembers2.js
index 3035b2cb56f..ac9b401a45c 100644
--- a/tests/baselines/reference/derivedClassOverridesProtectedMembers2.js
+++ b/tests/baselines/reference/derivedClassOverridesProtectedMembers2.js
@@ -94,8 +94,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived(a) {
-        var _this = _super.call(this, a) || this;
-        return _this;
+        return _super.call(this, a) || this;
     }
     Derived.prototype.b = function (a) { };
     Object.defineProperty(Derived.prototype, "c", {
diff --git a/tests/baselines/reference/derivedClassOverridesProtectedMembers3.js b/tests/baselines/reference/derivedClassOverridesProtectedMembers3.js
index 0e0c1c1ff01..d0d9d8fa0f5 100644
--- a/tests/baselines/reference/derivedClassOverridesProtectedMembers3.js
+++ b/tests/baselines/reference/derivedClassOverridesProtectedMembers3.js
@@ -103,16 +103,14 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1(a) {
-        var _this = _super.call(this, a) || this;
-        return _this;
+        return _super.call(this, a) || this;
     }
     return Derived1;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2(a) {
-        var _this = _super.call(this, a) || this;
-        return _this;
+        return _super.call(this, a) || this;
     }
     Derived2.prototype.b = function (a) { };
     return Derived2;
@@ -120,8 +118,7 @@ var Derived2 = (function (_super) {
 var Derived3 = (function (_super) {
     __extends(Derived3, _super);
     function Derived3(a) {
-        var _this = _super.call(this, a) || this;
-        return _this;
+        return _super.call(this, a) || this;
     }
     Object.defineProperty(Derived3.prototype, "c", {
         get: function () { return x; },
@@ -133,8 +130,7 @@ var Derived3 = (function (_super) {
 var Derived4 = (function (_super) {
     __extends(Derived4, _super);
     function Derived4(a) {
-        var _this = _super.call(this, a) || this;
-        return _this;
+        return _super.call(this, a) || this;
     }
     Object.defineProperty(Derived4.prototype, "c", {
         set: function (v) { },
@@ -146,24 +142,21 @@ var Derived4 = (function (_super) {
 var Derived5 = (function (_super) {
     __extends(Derived5, _super);
     function Derived5(a) {
-        var _this = _super.call(this, a) || this;
-        return _this;
+        return _super.call(this, a) || this;
     }
     return Derived5;
 }(Base));
 var Derived6 = (function (_super) {
     __extends(Derived6, _super);
     function Derived6(a) {
-        var _this = _super.call(this, a) || this;
-        return _this;
+        return _super.call(this, a) || this;
     }
     return Derived6;
 }(Base));
 var Derived7 = (function (_super) {
     __extends(Derived7, _super);
     function Derived7(a) {
-        var _this = _super.call(this, a) || this;
-        return _this;
+        return _super.call(this, a) || this;
     }
     Derived7.s = function (a) { };
     return Derived7;
@@ -171,8 +164,7 @@ var Derived7 = (function (_super) {
 var Derived8 = (function (_super) {
     __extends(Derived8, _super);
     function Derived8(a) {
-        var _this = _super.call(this, a) || this;
-        return _this;
+        return _super.call(this, a) || this;
     }
     Object.defineProperty(Derived8, "t", {
         get: function () { return x; },
@@ -184,8 +176,7 @@ var Derived8 = (function (_super) {
 var Derived9 = (function (_super) {
     __extends(Derived9, _super);
     function Derived9(a) {
-        var _this = _super.call(this, a) || this;
-        return _this;
+        return _super.call(this, a) || this;
     }
     Object.defineProperty(Derived9, "t", {
         set: function (v) { },
@@ -197,8 +188,7 @@ var Derived9 = (function (_super) {
 var Derived10 = (function (_super) {
     __extends(Derived10, _super);
     function Derived10(a) {
-        var _this = _super.call(this, a) || this;
-        return _this;
+        return _super.call(this, a) || this;
     }
     return Derived10;
 }(Base));
diff --git a/tests/baselines/reference/derivedClassOverridesPublicMembers.js b/tests/baselines/reference/derivedClassOverridesPublicMembers.js
index 703f1d4a833..92fbc07e774 100644
--- a/tests/baselines/reference/derivedClassOverridesPublicMembers.js
+++ b/tests/baselines/reference/derivedClassOverridesPublicMembers.js
@@ -92,8 +92,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived(a) {
-        var _this = _super.call(this, x) || this;
-        return _this;
+        return _super.call(this, x) || this;
     }
     Derived.prototype.b = function (a) { };
     Object.defineProperty(Derived.prototype, "c", {
diff --git a/tests/baselines/reference/derivedClassSuperCallsWithThisArg.js b/tests/baselines/reference/derivedClassSuperCallsWithThisArg.js
index 039e25919f8..504d414a608 100644
--- a/tests/baselines/reference/derivedClassSuperCallsWithThisArg.js
+++ b/tests/baselines/reference/derivedClassSuperCallsWithThisArg.js
@@ -42,8 +42,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.call(this, _this) || this;
-        return _this;
+        return _super.call(this, _this) || this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/destructuringParameterDeclaration5.js b/tests/baselines/reference/destructuringParameterDeclaration5.js
index 8781671853f..7ba178823df 100644
--- a/tests/baselines/reference/destructuringParameterDeclaration5.js
+++ b/tests/baselines/reference/destructuringParameterDeclaration5.js
@@ -65,8 +65,7 @@ var Class = (function () {
 var SubClass = (function (_super) {
     __extends(SubClass, _super);
     function SubClass() {
-        var _this = _super.call(this) || this;
-        return _this;
+        return _super.call(this) || this;
     }
     return SubClass;
 }(Class));
@@ -78,8 +77,7 @@ var D = (function () {
 var SubD = (function (_super) {
     __extends(SubD, _super);
     function SubD() {
-        var _this = _super.call(this) || this;
-        return _this;
+        return _super.call(this) || this;
     }
     return SubD;
 }(D));
diff --git a/tests/baselines/reference/es6ClassTest2.js b/tests/baselines/reference/es6ClassTest2.js
index 9217f890377..b3787405ff7 100644
--- a/tests/baselines/reference/es6ClassTest2.js
+++ b/tests/baselines/reference/es6ClassTest2.js
@@ -267,8 +267,7 @@ var SuperParent = (function () {
 var SuperChild = (function (_super) {
     __extends(SuperChild, _super);
     function SuperChild() {
-        var _this = _super.call(this, 1) || this;
-        return _this;
+        return _super.call(this, 1) || this;
     }
     SuperChild.prototype.b = function () {
         _super.prototype.b.call(this, 'str');
diff --git a/tests/baselines/reference/genericClassPropertyInheritanceSpecialization.js b/tests/baselines/reference/genericClassPropertyInheritanceSpecialization.js
index 86410aaf10e..28eaf464968 100644
--- a/tests/baselines/reference/genericClassPropertyInheritanceSpecialization.js
+++ b/tests/baselines/reference/genericClassPropertyInheritanceSpecialization.js
@@ -109,8 +109,7 @@ var PortalFx;
                 var Validator = (function (_super) {
                     __extends(Validator, _super);
                     function Validator(message) {
-                        var _this = _super.call(this, message) || this;
-                        return _this;
+                        return _super.call(this, message) || this;
                     }
                     return Validator;
                 }(Portal.Controls.Validators.Validator));
diff --git a/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes.js b/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes.js
index 582937e7c0a..b0974c26ede 100644
--- a/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes.js
+++ b/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes.js
@@ -52,8 +52,7 @@ var EndGate;
         var NumberTween = (function (_super) {
             __extends(NumberTween, _super);
             function NumberTween(from) {
-                var _this = _super.call(this, from) || this;
-                return _this;
+                return _super.call(this, from) || this;
             }
             return NumberTween;
         }(Tweening.Tween));
diff --git a/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes2.js b/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes2.js
index 88173a4cbe3..a403c0de0b3 100644
--- a/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes2.js
+++ b/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes2.js
@@ -51,8 +51,7 @@ var EndGate;
         var NumberTween = (function (_super) {
             __extends(NumberTween, _super);
             function NumberTween(from) {
-                var _this = _super.call(this, from) || this;
-                return _this;
+                return _super.call(this, from) || this;
             }
             return NumberTween;
         }(Tweening.Tween));
diff --git a/tests/baselines/reference/genericTypeConstraints.js b/tests/baselines/reference/genericTypeConstraints.js
index b82e261a14f..67303166aa3 100644
--- a/tests/baselines/reference/genericTypeConstraints.js
+++ b/tests/baselines/reference/genericTypeConstraints.js
@@ -38,8 +38,7 @@ var Bar = (function () {
 var BarExtended = (function (_super) {
     __extends(BarExtended, _super);
     function BarExtended() {
-        var _this = _super.call(this) || this;
-        return _this;
+        return _super.call(this) || this;
     }
     return BarExtended;
 }(Bar));
diff --git a/tests/baselines/reference/missingPropertiesOfClassExpression.js b/tests/baselines/reference/missingPropertiesOfClassExpression.js
index 34b60940aa9..c7b30882b14 100644
--- a/tests/baselines/reference/missingPropertiesOfClassExpression.js
+++ b/tests/baselines/reference/missingPropertiesOfClassExpression.js
@@ -15,8 +15,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var George = (function (_super) {
     __extends(George, _super);
     function George() {
-        var _this = _super.call(this) || this;
-        return _this;
+        return _super.call(this) || this;
     }
     return George;
 }((function () {
diff --git a/tests/baselines/reference/optionalParamArgsTest.js b/tests/baselines/reference/optionalParamArgsTest.js
index 374b0956509..1b603898aa6 100644
--- a/tests/baselines/reference/optionalParamArgsTest.js
+++ b/tests/baselines/reference/optionalParamArgsTest.js
@@ -162,8 +162,7 @@ var C2 = (function (_super) {
     __extends(C2, _super);
     function C2(v2) {
         if (v2 === void 0) { v2 = 6; }
-        var _this = _super.call(this, v2) || this;
-        return _this;
+        return _super.call(this, v2) || this;
     }
     return C2;
 }(C1));
diff --git a/tests/baselines/reference/parserRealSource11.js b/tests/baselines/reference/parserRealSource11.js
index fd2c017b637..eb05d13f4ed 100644
--- a/tests/baselines/reference/parserRealSource11.js
+++ b/tests/baselines/reference/parserRealSource11.js
@@ -2667,8 +2667,7 @@ var TypeScript;
     var MissingIdentifier = (function (_super) {
         __extends(MissingIdentifier, _super);
         function MissingIdentifier() {
-            var _this = _super.call(this, "__missing") || this;
-            return _this;
+            return _super.call(this, "__missing") || this;
         }
         MissingIdentifier.prototype.isMissing = function () {
             return true;
@@ -2707,8 +2706,7 @@ var TypeScript;
     var Expression = (function (_super) {
         __extends(Expression, _super);
         function Expression(nodeType) {
-            var _this = _super.call(this, nodeType) || this;
-            return _this;
+            return _super.call(this, nodeType) || this;
         }
         Expression.prototype.isExpression = function () { return true; };
         Expression.prototype.isStatementOrExpression = function () { return true; };
@@ -3165,8 +3163,7 @@ var TypeScript;
     var ModuleElement = (function (_super) {
         __extends(ModuleElement, _super);
         function ModuleElement(nodeType) {
-            var _this = _super.call(this, nodeType) || this;
-            return _this;
+            return _super.call(this, nodeType) || this;
         }
         return ModuleElement;
     }(AST));
@@ -3259,8 +3256,7 @@ var TypeScript;
     var VarDecl = (function (_super) {
         __extends(VarDecl, _super);
         function VarDecl(id, nest) {
-            var _this = _super.call(this, id, NodeType.VarDecl, nest) || this;
-            return _this;
+            return _super.call(this, id, NodeType.VarDecl, nest) || this;
         }
         VarDecl.prototype.isAmbient = function () { return hasFlag(this.varFlags, VarFlags.Ambient); };
         VarDecl.prototype.isExported = function () { return hasFlag(this.varFlags, VarFlags.Exported); };
@@ -3597,8 +3593,7 @@ var TypeScript;
     var InterfaceDeclaration = (function (_super) {
         __extends(InterfaceDeclaration, _super);
         function InterfaceDeclaration(name, members, extendsList, implementsList) {
-            var _this = _super.call(this, NodeType.InterfaceDeclaration, name, extendsList, implementsList, members) || this;
-            return _this;
+            return _super.call(this, NodeType.InterfaceDeclaration, name, extendsList, implementsList, members) || this;
         }
         InterfaceDeclaration.prototype.typeCheck = function (typeFlow) {
             return typeFlow.typeCheckInterface(this);
@@ -3992,8 +3987,7 @@ var TypeScript;
     var EndCode = (function (_super) {
         __extends(EndCode, _super);
         function EndCode() {
-            var _this = _super.call(this, NodeType.EndCode) || this;
-            return _this;
+            return _super.call(this, NodeType.EndCode) || this;
         }
         return EndCode;
     }(AST));
@@ -4650,8 +4644,7 @@ var TypeScript;
     var DebuggerStatement = (function (_super) {
         __extends(DebuggerStatement, _super);
         function DebuggerStatement() {
-            var _this = _super.call(this, NodeType.Debugger) || this;
-            return _this;
+            return _super.call(this, NodeType.Debugger) || this;
         }
         DebuggerStatement.prototype.emit = function (emitter, tokenId, startLine) {
             emitter.emitParensAndCommentsInPlace(this, true);
diff --git a/tests/baselines/reference/parserharness.js b/tests/baselines/reference/parserharness.js
index 059ac2efd8e..14ce4338176 100644
--- a/tests/baselines/reference/parserharness.js
+++ b/tests/baselines/reference/parserharness.js
@@ -2471,8 +2471,7 @@ var Harness;
     var Run = (function (_super) {
         __extends(Run, _super);
         function Run() {
-            var _this = _super.call(this, 'Test Run', null) || this;
-            return _this;
+            return _super.call(this, 'Test Run', null) || this;
         }
         Run.prototype.run = function () {
             emitLog('start');
diff --git a/tests/baselines/reference/strictModeInConstructor.js b/tests/baselines/reference/strictModeInConstructor.js
index ecd6bacd20a..da45bda5c6e 100644
--- a/tests/baselines/reference/strictModeInConstructor.js
+++ b/tests/baselines/reference/strictModeInConstructor.js
@@ -107,8 +107,7 @@ var Bs = (function (_super) {
     __extends(Bs, _super);
     function Bs() {
         "use strict"; // No error
-        var _this = _super.call(this) || this;
-        return _this;
+        return _super.call(this) || this;
     }
     return Bs;
 }(A));
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing2.js b/tests/baselines/reference/superCallBeforeThisAccessing2.js
index 91cc3d28dd6..7331718a9ed 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing2.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing2.js
@@ -24,8 +24,7 @@ var Base = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.call(this, function () { _this._t; }) || this;
-        return _this;
+        return _super.call(this, function () { _this._t; }) || this;
     }
     return D;
 }(Base));
diff --git a/tests/baselines/reference/superCallBeforeThisAccessing6.js b/tests/baselines/reference/superCallBeforeThisAccessing6.js
index 4eb8e5266c2..e4dfb3f714a 100644
--- a/tests/baselines/reference/superCallBeforeThisAccessing6.js
+++ b/tests/baselines/reference/superCallBeforeThisAccessing6.js
@@ -24,8 +24,7 @@ var Base = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.call(this, _this) || this;
-        return _this;
+        return _super.call(this, this) || this;
     }
     return D;
 }(Base));
diff --git a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType1.js b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType1.js
index 27f3db51453..bc196299bf9 100644
--- a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType1.js
+++ b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType1.js
@@ -20,8 +20,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.call(this) || this;
-        return _this;
+        return _super.call(this) || this;
     }
     return D;
 }(B));
diff --git a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType2.js b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType2.js
index a8d5e8008ac..8a0ef085590 100644
--- a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType2.js
+++ b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericType2.js
@@ -19,8 +19,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.call(this) || this;
-        return _this;
+        return _super.call(this) || this;
     }
     return D;
 }(B));
diff --git a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithIncorrectNumberOfTypeArguments1.js b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithIncorrectNumberOfTypeArguments1.js
index b12a3eef6d4..0529d5e3dc2 100644
--- a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithIncorrectNumberOfTypeArguments1.js
+++ b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithIncorrectNumberOfTypeArguments1.js
@@ -25,8 +25,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.call(this, function (value) { return String(value); }) || this;
-        return _this;
+        return _super.call(this, function (value) { return String(value); }) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithNoTypeArguments1.js b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithNoTypeArguments1.js
index c78e6693f16..fb08ec28902 100644
--- a/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithNoTypeArguments1.js
+++ b/tests/baselines/reference/superCallFromClassThatDerivesFromGenericTypeButWithNoTypeArguments1.js
@@ -25,8 +25,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.call(this, function (value) { return String(value); }) || this;
-        return _this;
+        return _super.call(this, function (value) { return String(value); }) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/superCallFromClassThatDerivesNonGenericTypeButWithTypeArguments1.js b/tests/baselines/reference/superCallFromClassThatDerivesNonGenericTypeButWithTypeArguments1.js
index 32d2065dd3f..50153391f62 100644
--- a/tests/baselines/reference/superCallFromClassThatDerivesNonGenericTypeButWithTypeArguments1.js
+++ b/tests/baselines/reference/superCallFromClassThatDerivesNonGenericTypeButWithTypeArguments1.js
@@ -25,8 +25,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.call(this, function (value) { return String(value); }) || this;
-        return _this;
+        return _super.call(this, function (value) { return String(value); }) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/superCallInsideClassDeclaration.js b/tests/baselines/reference/superCallInsideClassDeclaration.js
index b696b4a302f..05e44119608 100644
--- a/tests/baselines/reference/superCallInsideClassDeclaration.js
+++ b/tests/baselines/reference/superCallInsideClassDeclaration.js
@@ -39,8 +39,7 @@ var B = (function (_super) {
         var D = (function (_super) {
             __extends(D, _super);
             function D() {
-                var _this = _super.call(this) || this;
-                return _this;
+                return _super.call(this) || this;
             }
             return D;
         }(C));
diff --git a/tests/baselines/reference/superCallInsideClassExpression.js b/tests/baselines/reference/superCallInsideClassExpression.js
index 829311f237c..3d55fe11cff 100644
--- a/tests/baselines/reference/superCallInsideClassExpression.js
+++ b/tests/baselines/reference/superCallInsideClassExpression.js
@@ -39,8 +39,7 @@ var B = (function (_super) {
         var D = (function (_super) {
             __extends(class_1, _super);
             function class_1() {
-                var _this = _super.call(this) || this;
-                return _this;
+                return _super.call(this) || this;
             }
             return class_1;
         }(C));
diff --git a/tests/baselines/reference/superCallParameterContextualTyping1.js b/tests/baselines/reference/superCallParameterContextualTyping1.js
index 0fe27f493e8..d8491b4ee83 100644
--- a/tests/baselines/reference/superCallParameterContextualTyping1.js
+++ b/tests/baselines/reference/superCallParameterContextualTyping1.js
@@ -28,8 +28,7 @@ var B = (function (_super) {
     __extends(B, _super);
     // Ensure 'value' is of type 'number (and not '{}') by using its 'toExponential()' method.
     function B() {
-        var _this = _super.call(this, function (value) { return String(value.toExponential()); }) || this;
-        return _this;
+        return _super.call(this, function (value) { return String(value.toExponential()); }) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/superCallParameterContextualTyping2.js b/tests/baselines/reference/superCallParameterContextualTyping2.js
index f970be44aff..9868a7db124 100644
--- a/tests/baselines/reference/superCallParameterContextualTyping2.js
+++ b/tests/baselines/reference/superCallParameterContextualTyping2.js
@@ -27,8 +27,7 @@ var C = (function (_super) {
     __extends(C, _super);
     // Ensure 'value' is not of type 'any' by invoking it with type arguments.
     function C() {
-        var _this = _super.call(this, function (value) { return String(value()); }) || this;
-        return _this;
+        return _super.call(this, function (value) { return String(value()); }) || this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/superWithGenericSpecialization.js b/tests/baselines/reference/superWithGenericSpecialization.js
index 96303dab4ed..a0381d0b944 100644
--- a/tests/baselines/reference/superWithGenericSpecialization.js
+++ b/tests/baselines/reference/superWithGenericSpecialization.js
@@ -28,8 +28,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.call(this) || this;
-        return _this;
+        return _super.call(this) || this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/superWithGenerics.js b/tests/baselines/reference/superWithGenerics.js
index 36b48554871..803f229bd4b 100644
--- a/tests/baselines/reference/superWithGenerics.js
+++ b/tests/baselines/reference/superWithGenerics.js
@@ -20,8 +20,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.call(this) || this;
-        return _this;
+        return _super.call(this) || this;
     }
     return D;
 }(B));
diff --git a/tests/baselines/reference/targetTypeBaseCalls.js b/tests/baselines/reference/targetTypeBaseCalls.js
index 8581526c1b6..cac93023a00 100644
--- a/tests/baselines/reference/targetTypeBaseCalls.js
+++ b/tests/baselines/reference/targetTypeBaseCalls.js
@@ -35,8 +35,7 @@ new Foo(function (s) { s = 5; }); // error, if types are applied correctly
 var Bar = (function (_super) {
     __extends(Bar, _super);
     function Bar() {
-        var _this = _super.call(this, function (s) { s = 5; }) || this;
-        return _this;
+        return _super.call(this, function (s) { s = 5; }) || this;
     }
     return Bar;
 }(Foo)); // error, if types are applied correctly
diff --git a/tests/baselines/reference/thisInInvalidContexts.js b/tests/baselines/reference/thisInInvalidContexts.js
index 7872aa121ed..7fcfaf9d317 100644
--- a/tests/baselines/reference/thisInInvalidContexts.js
+++ b/tests/baselines/reference/thisInInvalidContexts.js
@@ -70,8 +70,7 @@ var ClassWithNoInitializer = (function (_super) {
     __extends(ClassWithNoInitializer, _super);
     //'this' in optional super call
     function ClassWithNoInitializer() {
-        var _this = _super.call(this, _this) || this;
-        return _this;
+        return _super.call(this, _this) || this;
     }
     return ClassWithNoInitializer;
 }(BaseErrClass));
diff --git a/tests/baselines/reference/thisInInvalidContextsExternalModule.js b/tests/baselines/reference/thisInInvalidContextsExternalModule.js
index e656824ae66..546863b5216 100644
--- a/tests/baselines/reference/thisInInvalidContextsExternalModule.js
+++ b/tests/baselines/reference/thisInInvalidContextsExternalModule.js
@@ -71,8 +71,7 @@ var ClassWithNoInitializer = (function (_super) {
     __extends(ClassWithNoInitializer, _super);
     //'this' in optional super call
     function ClassWithNoInitializer() {
-        var _this = _super.call(this, _this) || this;
-        return _this;
+        return _super.call(this, _this) || this;
     }
     return ClassWithNoInitializer;
 }(BaseErrClass));
diff --git a/tests/baselines/reference/thisInSuperCall.js b/tests/baselines/reference/thisInSuperCall.js
index 1c1f11ffbc8..2a4d15973ab 100644
--- a/tests/baselines/reference/thisInSuperCall.js
+++ b/tests/baselines/reference/thisInSuperCall.js
@@ -36,8 +36,7 @@ var Base = (function () {
 var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo() {
-        var _this = _super.call(this, _this) || this;
-        return _this;
+        return _super.call(this, _this) || this;
     }
     return Foo;
 }(Base));
diff --git a/tests/baselines/reference/thisInSuperCall2.js b/tests/baselines/reference/thisInSuperCall2.js
index 6288082ed64..eabfa9d562c 100644
--- a/tests/baselines/reference/thisInSuperCall2.js
+++ b/tests/baselines/reference/thisInSuperCall2.js
@@ -33,8 +33,7 @@ var Base = (function () {
 var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo() {
-        var _this = _super.call(this, _this) || this;
-        return _this;
+        return _super.call(this, _this) || this;
     }
     return Foo;
 }(Base));
diff --git a/tests/baselines/reference/unknownSymbols1.js b/tests/baselines/reference/unknownSymbols1.js
index 5e2bb509a23..832868c4b8f 100644
--- a/tests/baselines/reference/unknownSymbols1.js
+++ b/tests/baselines/reference/unknownSymbols1.js
@@ -63,8 +63,7 @@ var C3 = (function () {
 var C4 = (function (_super) {
     __extends(C4, _super);
     function C4() {
-        var _this = _super.call(this, asdf) || this;
-        return _this;
+        return _super.call(this, asdf) || this;
     }
     return C4;
 }(C3));
diff --git a/tests/baselines/reference/validUseOfThisInSuper.js b/tests/baselines/reference/validUseOfThisInSuper.js
index bbd564db366..483e905b48a 100644
--- a/tests/baselines/reference/validUseOfThisInSuper.js
+++ b/tests/baselines/reference/validUseOfThisInSuper.js
@@ -24,8 +24,7 @@ var Base = (function () {
 var Super = (function (_super) {
     __extends(Super, _super);
     function Super() {
-        var _this = _super.call(this, (function () { return _this; })()) || this;
-        return _this;
+        return _super.call(this, (function () { return _this; })()) || this;
     }
     return Super;
 }(Base));

From 6580262c950626b9e14f4a1de90a8c420d6c5069 Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Tue, 20 Sep 2016 12:30:33 -0400
Subject: [PATCH 31/47] Initialize instead of letting the value be potentially
 undefined.

---
 src/compiler/transformers/es6.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/compiler/transformers/es6.ts b/src/compiler/transformers/es6.ts
index 5748739cb23..a69dcdfbe6a 100644
--- a/src/compiler/transformers/es6.ts
+++ b/src/compiler/transformers/es6.ts
@@ -838,7 +838,7 @@ namespace ts {
             startLexicalEnvironment();
 
             let statementOffset = -1;
-            let thisCaptureStatus: SuperCaptureResult | undefined;
+            let thisCaptureStatus = SuperCaptureResult.NoReplacement;
             if (hasSynthesizedSuper) {
                 // If a super call has already been synthesized,
                 // we're going to assume that we should just transform everything after that.

From f2de4508dfcb72ca33964d6cb4daea1065051214 Mon Sep 17 00:00:00 2001
From: Ron Buckton <rbuckton@microsoft.com>
Date: Mon, 26 Sep 2016 11:20:24 -0700
Subject: [PATCH 32/47] Extract emit-specific properties into EmitNode

---
 src/compiler/binder.ts                     |   6 +-
 src/compiler/comments.ts                   |  20 +-
 src/compiler/core.ts                       |  67 +++-
 src/compiler/emitter.ts                    | 151 +++++---
 src/compiler/factory.ts                    |  34 +-
 src/compiler/transformer.ts                | 413 +++++++--------------
 src/compiler/transformers/destructuring.ts |  12 +-
 src/compiler/transformers/es6.ts           | 109 +++---
 src/compiler/transformers/es7.ts           |   4 +
 src/compiler/transformers/generators.ts    |  15 +-
 src/compiler/transformers/jsx.ts           |   4 +
 src/compiler/transformers/module/es6.ts    |   4 +
 src/compiler/transformers/module/module.ts |  39 +-
 src/compiler/transformers/module/system.ts |  24 +-
 src/compiler/transformers/ts.ts            |  74 ++--
 src/compiler/types.ts                      |  16 +-
 16 files changed, 492 insertions(+), 500 deletions(-)

diff --git a/src/compiler/binder.ts b/src/compiler/binder.ts
index 49434e80aba..e2d31162127 100644
--- a/src/compiler/binder.ts
+++ b/src/compiler/binder.ts
@@ -2592,7 +2592,7 @@ namespace ts {
         }
 
         // Currently, we only support generators that were originally async function bodies.
-        if (asteriskToken && node.emitFlags & NodeEmitFlags.AsyncFunctionBody) {
+        if (asteriskToken && getEmitFlags(node) & EmitFlags.AsyncFunctionBody) {
             transformFlags |= TransformFlags.AssertGenerator;
         }
 
@@ -2667,7 +2667,7 @@ namespace ts {
             // down-level generator.
             // Currently we do not support transforming any other generator fucntions
             // down level.
-            if (asteriskToken && node.emitFlags & NodeEmitFlags.AsyncFunctionBody) {
+            if (asteriskToken && getEmitFlags(node) & EmitFlags.AsyncFunctionBody) {
                 transformFlags |= TransformFlags.AssertGenerator;
             }
         }
@@ -2698,7 +2698,7 @@ namespace ts {
         // down-level generator.
         // Currently we do not support transforming any other generator fucntions
         // down level.
-        if (asteriskToken && node.emitFlags & NodeEmitFlags.AsyncFunctionBody) {
+        if (asteriskToken && getEmitFlags(node) & EmitFlags.AsyncFunctionBody) {
             transformFlags |= TransformFlags.AssertGenerator;
         }
 
diff --git a/src/compiler/comments.ts b/src/compiler/comments.ts
index 1bca13a4bdb..f9f8e74d4ca 100644
--- a/src/compiler/comments.ts
+++ b/src/compiler/comments.ts
@@ -41,11 +41,11 @@ namespace ts {
             }
 
             if (node) {
-                const { pos, end } = node.commentRange || node;
-                const emitFlags = node.emitFlags;
+                const { pos, end } = getCommentRange(node);
+                const emitFlags = getEmitFlags(node);
                 if ((pos < 0 && end < 0) || (pos === end)) {
                     // Both pos and end are synthesized, so just emit the node without comments.
-                    if (emitFlags & NodeEmitFlags.NoNestedComments) {
+                    if (emitFlags & EmitFlags.NoNestedComments) {
                         disableCommentsAndEmit(node, emitCallback);
                     }
                     else {
@@ -58,8 +58,8 @@ namespace ts {
                     }
 
                     const isEmittedNode = node.kind !== SyntaxKind.NotEmittedStatement;
-                    const skipLeadingComments = pos < 0 || (emitFlags & NodeEmitFlags.NoLeadingComments) !== 0;
-                    const skipTrailingComments = end < 0 || (emitFlags & NodeEmitFlags.NoTrailingComments) !== 0;
+                    const skipLeadingComments = pos < 0 || (emitFlags & EmitFlags.NoLeadingComments) !== 0;
+                    const skipTrailingComments = end < 0 || (emitFlags & EmitFlags.NoTrailingComments) !== 0;
 
                     // Emit leading comments if the position is not synthesized and the node
                     // has not opted out from emitting leading comments.
@@ -90,7 +90,7 @@ namespace ts {
                         performance.measure("commentTime", "preEmitNodeWithComment");
                     }
 
-                    if (emitFlags & NodeEmitFlags.NoNestedComments) {
+                    if (emitFlags & EmitFlags.NoNestedComments) {
                         disableCommentsAndEmit(node, emitCallback);
                     }
                     else {
@@ -125,9 +125,9 @@ namespace ts {
             }
 
             const { pos, end } = detachedRange;
-            const emitFlags = node.emitFlags;
-            const skipLeadingComments = pos < 0 || (emitFlags & NodeEmitFlags.NoLeadingComments) !== 0;
-            const skipTrailingComments = disabled || end < 0 || (emitFlags & NodeEmitFlags.NoTrailingComments) !== 0;
+            const emitFlags = getEmitFlags(node);
+            const skipLeadingComments = pos < 0 || (emitFlags & EmitFlags.NoLeadingComments) !== 0;
+            const skipTrailingComments = disabled || end < 0 || (emitFlags & EmitFlags.NoTrailingComments) !== 0;
 
             if (!skipLeadingComments) {
                 emitDetachedCommentsAndUpdateCommentsInfo(detachedRange);
@@ -137,7 +137,7 @@ namespace ts {
                 performance.measure("commentTime", "preEmitBodyWithDetachedComments");
             }
 
-            if (emitFlags & NodeEmitFlags.NoNestedComments) {
+            if (emitFlags & EmitFlags.NoNestedComments) {
                 disableCommentsAndEmit(node, emitCallback);
             }
             else {
diff --git a/src/compiler/core.ts b/src/compiler/core.ts
index 72d05e1cfd7..6a37292c532 100644
--- a/src/compiler/core.ts
+++ b/src/compiler/core.ts
@@ -824,6 +824,72 @@ namespace ts {
         };
     }
 
+    /**
+     * High-order function, creates a function that executes a function composition.
+     * For example, `chain(a, b)` is the equivalent of `x => ((a', b') => y => b'(a'(y)))(a(x), b(x))`
+     *
+     * @param args The functions to chain.
+     */
+    export function chain<T, U>(...args: ((t: T) => (u: U) => U)[]): (t: T) => (u: U) => U;
+    export function chain<T, U>(a: (t: T) => (u: U) => U, b: (t: T) => (u: U) => U, c: (t: T) => (u: U) => U, d: (t: T) => (u: U) => U, e: (t: T) => (u: U) => U): (t: T) => (u: U) => U {
+        if (e) {
+            const args: ((t: T) => (u: U) => U)[] = [];
+            for (let i = 0; i < arguments.length; i++) {
+                args[i] = arguments[i];
+            }
+
+            return t => compose(...map(args, f => f(t)));
+        }
+        else if (d) {
+            return t => compose(a(t), b(t), c(t), d(t));
+        }
+        else if (c) {
+            return t => compose(a(t), b(t), c(t));
+        }
+        else if (b) {
+            return t => compose(a(t), b(t));
+        }
+        else if (a) {
+            return t => compose(a(t));
+        }
+        else {
+            return t => u => u;
+        }
+    }
+
+    /**
+     * High-order function, composes functions. Note that functions are composed inside-out;
+     * for example, `compose(a, b)` is the equivalent of `x => b(a(x))`.
+     *
+     * @param args The functions to compose.
+     */
+    export function compose<T>(...args: ((t: T) => T)[]): (t: T) => T;
+    export function compose<T>(a: (t: T) => T, b: (t: T) => T, c: (t: T) => T, d: (t: T) => T, e: (t: T) => T): (t: T) => T {
+        if (e) {
+            const args: ((t: T) => T)[] = [];
+            for (let i = 0; i < arguments.length; i++) {
+                args[i] = arguments[i];
+            }
+
+            return t => reduceLeft<(t: T) => T, T>(args, (u, f) => f(u), t);
+        }
+        else if (d) {
+            return t => d(c(b(a(t))));
+        }
+        else if (c) {
+            return t => c(b(a(t)));
+        }
+        else if (b) {
+            return t => b(a(t));
+        }
+        else if (a) {
+            return t => a(t);
+        }
+        else {
+            return t => t;
+        }
+    }
+
     function formatStringFromArgs(text: string, args: { [index: number]: any; }, baseIndex?: number): string {
         baseIndex = baseIndex || 0;
 
@@ -1715,7 +1781,6 @@ namespace ts {
         this.transformFlags = TransformFlags.None;
         this.parent = undefined;
         this.original = undefined;
-        this.transformId = 0;
     }
 
     export let objectAllocator: ObjectAllocator = {
diff --git a/src/compiler/emitter.ts b/src/compiler/emitter.ts
index 14e743cf59f..5487057bbca 100644
--- a/src/compiler/emitter.ts
+++ b/src/compiler/emitter.ts
@@ -244,7 +244,6 @@ const _super = (function (geti, seti) {
 
         // Extract helpers from the result
         const {
-            getTokenSourceMapRange,
             isSubstitutionEnabled,
             isEmitNotificationEnabled,
             onSubstituteNode,
@@ -351,7 +350,7 @@ const _super = (function (geti, seti) {
             currentFileIdentifiers = node.identifiers;
             sourceMap.setSourceFile(node);
             comments.setSourceFile(node);
-            emitNodeWithNotification(node, emitWorker);
+            emitNodeWithNotification(node, emitWithSubstitution);
         }
 
         /**
@@ -361,7 +360,6 @@ const _super = (function (geti, seti) {
             emitNodeWithNotification(node, emitWithComments);
         }
 
-
         /**
          * Emits a node with comments.
          *
@@ -379,17 +377,37 @@ const _super = (function (geti, seti) {
          * and should only be called indirectly from emitWithComments.
          */
         function emitWithSourceMap(node: Node) {
-            emitNodeWithSourceMap(node, emitWorker);
+            emitNodeWithSourceMap(node, emitWithSubstitution);
         }
 
+        /**
+         * Emits a node with possible substitution.
+         *
+         * NOTE: Do not call this method directly. It is part of the emit pipeline
+         * and should only be called indirectly from emitWithSourceMap or
+         * emitIdentifierNameWithComments.
+         */
+        function emitWithSubstitution(node: Node) {
+            emitNodeWithSubstitution(node, /*isExpression*/ false, emitWorker);
+        }
+
+        /**
+         * Emits an IdentifierName.
+         */
         function emitIdentifierName(node: Identifier) {
             if (node) {
                 emitNodeWithNotification(node, emitIdentifierNameWithComments);
             }
         }
 
+        /**
+         * Emits an IdentifierName with possible comments.
+         *
+         * NOTE: Do not call this method directly. It is part of the emit pipeline
+         * and should only be called indirectly from emitIdentifierName.
+         */
         function emitIdentifierNameWithComments(node: Identifier) {
-            emitNodeWithComments(node, emitWorker);
+            emitNodeWithComments(node, emitWithSubstitution);
         }
 
         /**
@@ -410,18 +428,30 @@ const _super = (function (geti, seti) {
         }
 
         /**
-         * Emits an expression with source maps.
+         * Emits an expression with possible source maps.
          *
          * NOTE: Do not call this method directly. It is part of the emitExpression pipeline
          * and should only be called indirectly from emitExpressionWithComments.
          */
         function emitExpressionWithSourceMap(node: Expression) {
-            emitNodeWithSourceMap(node, emitExpressionWorker);
+            emitNodeWithSourceMap(node, emitExpressionWithSubstitution);
         }
 
         /**
-         * Emits a node with emit notification if available.
+         * Emits an expression with possible substitution.
+         *
+         * NOTE: Do not call this method directly. It is part of the emitExpression pipeline
+         * and should only be called indirectly from emitExpressionWithSourceMap or
+         * from emitWorker.
          */
+        function emitExpressionWithSubstitution(node: Expression) {
+            emitNodeWithSubstitution(node, /*isExpression*/ true, emitExpressionWorker);
+        }
+
+        /**
+         * Emits a node with possible emit notification.
+         */
+        // TODO(rbuckton): Move this into transformer.ts
         function emitNodeWithNotification(node: Node, emitCallback: (node: Node) => void) {
             if (node) {
                 if (isEmitNotificationEnabled(node)) {
@@ -433,6 +463,10 @@ const _super = (function (geti, seti) {
             }
         }
 
+        /**
+         * Emits a node with possible source maps.
+         */
+        // TODO(rbuckton): Move this into sourcemap.ts
         function emitNodeWithSourceMap(node: Node, emitCallback: (node: Node) => void) {
             if (node) {
                 emitStart(/*range*/ node, /*contextNode*/ node, shouldSkipLeadingSourceMapForNode, shouldSkipSourceMapForChildren, getSourceMapRange);
@@ -441,10 +475,6 @@ const _super = (function (geti, seti) {
             }
         }
 
-        function getSourceMapRange(node: Node) {
-            return node.sourceMapRange || node;
-        }
-
         /**
          * Determines whether to skip leading comment emit for a node.
          *
@@ -453,9 +483,10 @@ const _super = (function (geti, seti) {
          *
          * @param node A Node.
          */
+        // TODO(rbuckton): Move this into comments.ts
         function shouldSkipLeadingCommentsForNode(node: Node) {
             return isNotEmittedStatement(node)
-                || (node.emitFlags & NodeEmitFlags.NoLeadingComments) !== 0;
+                || (getEmitFlags(node) & EmitFlags.NoLeadingComments) !== 0;
         }
 
         /**
@@ -466,12 +497,12 @@ const _super = (function (geti, seti) {
          *
          * @param node A Node.
          */
+        // TODO(rbuckton): Move this into sourcemap.ts
         function shouldSkipLeadingSourceMapForNode(node: Node) {
             return isNotEmittedStatement(node)
-                || (node.emitFlags & NodeEmitFlags.NoLeadingSourceMap) !== 0;
+                || (getEmitFlags(node) & EmitFlags.NoLeadingSourceMap) !== 0;
         }
 
-
         /**
          * Determines whether to skip source map emit for the end position of a node.
          *
@@ -480,9 +511,10 @@ const _super = (function (geti, seti) {
          *
          * @param node A Node.
          */
+        // TODO(rbuckton): Move this into sourcemap.ts
         function shouldSkipTrailingSourceMapForNode(node: Node) {
             return isNotEmittedStatement(node)
-                || (node.emitFlags & NodeEmitFlags.NoTrailingSourceMap) !== 0;
+                || (getEmitFlags(node) & EmitFlags.NoTrailingSourceMap) !== 0;
         }
 
         /**
@@ -490,15 +522,34 @@ const _super = (function (geti, seti) {
          *
          * We do not emit source maps for a node that has NodeEmitFlags.NoNestedSourceMaps.
          */
+        // TODO(rbuckton): Move this into sourcemap.ts
         function shouldSkipSourceMapForChildren(node: Node) {
-            return (node.emitFlags & NodeEmitFlags.NoNestedSourceMaps) !== 0;
+            return (getEmitFlags(node) & EmitFlags.NoNestedSourceMaps) !== 0;
         }
 
-        function emitWorker(node: Node): void {
-            if (tryEmitSubstitute(node, emitWorker, /*isExpression*/ false)) {
-                return;
+        /**
+         * Emits a node with possible substitution.
+         */
+        // TODO(rbuckton): Move this into transformer.ts
+        function emitNodeWithSubstitution(node: Node, isExpression: boolean, emitCallback: (node: Node) => void) {
+            if (isSubstitutionEnabled(node) && (getEmitFlags(node) & EmitFlags.NoSubstitution) === 0) {
+                const substitute = onSubstituteNode(node, isExpression);
+                if (substitute !== node) {
+                    emitCallback(substitute);
+                    return;
+                }
             }
 
+            emitCallback(node);
+        }
+
+        /**
+         * Emits a node.
+         *
+         * NOTE: Do not call this method directly. It is part of the emit pipeline
+         * and should only be called indirectly from emitNodeWithSubstitution.
+         */
+        function emitWorker(node: Node): void {
             const kind = node.kind;
             switch (kind) {
                 // Pseudo-literals
@@ -749,15 +800,17 @@ const _super = (function (geti, seti) {
             }
 
             if (isExpression(node)) {
-                return emitExpressionWorker(node);
+                return emitExpressionWithSubstitution(node);
             }
         }
 
+        /**
+         * Emits an expression.
+         *
+         * NOTE: Do not call this method directly. It is part of the emitExpression pipeline
+         * and should only be called indirectly from emitExpressionWithNotification.
+         */
         function emitExpressionWorker(node: Node) {
-            if (tryEmitSubstitute(node, emitExpressionWorker, /*isExpression*/ true)) {
-                return;
-            }
-
             const kind = node.kind;
             switch (kind) {
                 // Literals
@@ -881,7 +934,7 @@ const _super = (function (geti, seti) {
         //
 
         function emitIdentifier(node: Identifier) {
-            if (node.emitFlags & NodeEmitFlags.UMDDefine) {
+            if (getEmitFlags(node) & EmitFlags.UMDDefine) {
                 writeLines(umdHelper);
             }
             else {
@@ -1154,7 +1207,7 @@ const _super = (function (geti, seti) {
                 write("{}");
             }
             else {
-                const indentedFlag = node.emitFlags & NodeEmitFlags.Indented;
+                const indentedFlag = getEmitFlags(node) & EmitFlags.Indented;
                 if (indentedFlag) {
                     increaseIndent();
                 }
@@ -1176,7 +1229,7 @@ const _super = (function (geti, seti) {
 
             let indentBeforeDot = false;
             let indentAfterDot = false;
-            if (!(node.emitFlags & NodeEmitFlags.NoIndentation)) {
+            if (!(getEmitFlags(node) & EmitFlags.NoIndentation)) {
                 const dotRangeStart = node.expression.end;
                 const dotRangeEnd = skipTrivia(currentText, node.expression.end) + 1;
                 const dotToken = <Node>{ kind: SyntaxKind.DotToken, pos: dotRangeStart, end: dotRangeEnd };
@@ -1419,7 +1472,7 @@ const _super = (function (geti, seti) {
         }
 
         function emitBlockStatements(node: Block) {
-            if (node.emitFlags & NodeEmitFlags.SingleLine) {
+            if (getEmitFlags(node) & EmitFlags.SingleLine) {
                 emitList(node, node.statements, ListFormat.SingleLineBlockStatements);
             }
             else {
@@ -1623,12 +1676,12 @@ const _super = (function (geti, seti) {
             const body = node.body;
             if (body) {
                 if (isBlock(body)) {
-                    const indentedFlag = node.emitFlags & NodeEmitFlags.Indented;
+                    const indentedFlag = getEmitFlags(node) & EmitFlags.Indented;
                     if (indentedFlag) {
                         increaseIndent();
                     }
 
-                    if (node.emitFlags & NodeEmitFlags.ReuseTempVariableScope) {
+                    if (getEmitFlags(node) & EmitFlags.ReuseTempVariableScope) {
                         emitSignatureHead(node);
                         emitBlockFunctionBody(node, body);
                     }
@@ -1672,7 +1725,7 @@ const _super = (function (geti, seti) {
             // * A non-synthesized body's start and end position are on different lines.
             // * Any statement in the body starts on a new line.
 
-            if (body.emitFlags & NodeEmitFlags.SingleLine) {
+            if (getEmitFlags(body) & EmitFlags.SingleLine) {
                 return true;
             }
 
@@ -1743,7 +1796,7 @@ const _super = (function (geti, seti) {
             write("class");
             emitNodeWithPrefix(" ", node.name, emitIdentifierName);
 
-            const indentedFlag = node.emitFlags & NodeEmitFlags.Indented;
+            const indentedFlag = getEmitFlags(node) & EmitFlags.Indented;
             if (indentedFlag) {
                 increaseIndent();
             }
@@ -2077,7 +2130,7 @@ const _super = (function (geti, seti) {
             // but rather a trailing comment on the previous node.
             const initializer = node.initializer;
             if (!shouldSkipLeadingCommentsForNode(initializer)) {
-                const commentRange = initializer.commentRange || initializer;
+                const commentRange = getCommentRange(initializer);
                 emitTrailingCommentsOfPosition(commentRange.pos);
             }
 
@@ -2149,23 +2202,23 @@ const _super = (function (geti, seti) {
         }
 
         function emitHelpers(node: Node) {
-            const emitFlags = node.emitFlags;
+            const emitFlags = getEmitFlags(node);
             let helpersEmitted = false;
-            if (emitFlags & NodeEmitFlags.EmitEmitHelpers) {
+            if (emitFlags & EmitFlags.EmitEmitHelpers) {
                 helpersEmitted = emitEmitHelpers(currentSourceFile);
             }
 
-            if (emitFlags & NodeEmitFlags.EmitExportStar) {
+            if (emitFlags & EmitFlags.EmitExportStar) {
                 writeLines(exportStarHelper);
                 helpersEmitted = true;
             }
 
-            if (emitFlags & NodeEmitFlags.EmitSuperHelper) {
+            if (emitFlags & EmitFlags.EmitSuperHelper) {
                 writeLines(superHelper);
                 helpersEmitted = true;
             }
 
-            if (emitFlags & NodeEmitFlags.EmitAdvancedSuperHelper) {
+            if (emitFlags & EmitFlags.EmitAdvancedSuperHelper) {
                 writeLines(advancedSuperHelper);
                 helpersEmitted = true;
             }
@@ -2287,19 +2340,7 @@ const _super = (function (geti, seti) {
             }
         }
 
-        function tryEmitSubstitute(node: Node, emitNode: (node: Node) => void, isExpression: boolean) {
-            if (isSubstitutionEnabled(node) && (node.emitFlags & NodeEmitFlags.NoSubstitution) === 0) {
-                const substitute = onSubstituteNode(node, isExpression);
-                if (substitute !== node) {
-                    substitute.emitFlags |= NodeEmitFlags.NoSubstitution;
-                    emitNode(substitute);
-                    return true;
-                }
-            }
-
-            return false;
-        }
-
+        // TODO(rbuckton): Move this into a transformer
         function tryEmitConstantValue(node: PropertyAccessExpression | ElementAccessExpression): boolean {
             const constantValue = tryGetConstEnumValue(node);
             if (constantValue !== undefined) {
@@ -2440,7 +2481,7 @@ const _super = (function (geti, seti) {
                     }
 
                     if (shouldEmitInterveningComments) {
-                        const commentRange = child.commentRange || child;
+                        const commentRange = getCommentRange(child);
                         emitTrailingCommentsOfPosition(commentRange.pos);
                     }
                     else {
@@ -2502,11 +2543,11 @@ const _super = (function (geti, seti) {
         }
 
         function shouldSkipLeadingSourceMapForToken(contextNode: Node) {
-            return (contextNode.emitFlags & NodeEmitFlags.NoTokenLeadingSourceMaps) !== 0;
+            return (getEmitFlags(contextNode) & EmitFlags.NoTokenLeadingSourceMaps) !== 0;
         }
 
         function shouldSkipTrailingSourceMapForToken(contextNode: Node) {
-            return (contextNode.emitFlags & NodeEmitFlags.NoTokenTrailingSourceMaps) !== 0;
+            return (getEmitFlags(contextNode) & EmitFlags.NoTokenTrailingSourceMaps) !== 0;
         }
 
         function writeTokenText(token: SyntaxKind, pos?: number) {
diff --git a/src/compiler/factory.ts b/src/compiler/factory.ts
index 16eeb86f59a..c0565f6e91d 100644
--- a/src/compiler/factory.ts
+++ b/src/compiler/factory.ts
@@ -76,7 +76,7 @@ namespace ts {
         // the original node. We also need to exclude specific properties and only include own-
         // properties (to skip members already defined on the shared prototype).
         const clone = <T>createNode(node.kind, /*location*/ undefined, node.flags);
-        clone.original = node;
+        setOriginalNode(clone, node);
 
         for (const key in node) {
             if (clone.hasOwnProperty(key) || !node.hasOwnProperty(key)) {
@@ -435,7 +435,7 @@ namespace ts {
     export function createPropertyAccess(expression: Expression, name: string | Identifier, location?: TextRange, flags?: NodeFlags) {
         const node = <PropertyAccessExpression>createNode(SyntaxKind.PropertyAccessExpression, location, flags);
         node.expression = parenthesizeForAccess(expression);
-        node.emitFlags = NodeEmitFlags.NoIndentation;
+        (node.emitNode || (node.emitNode = {})).flags |= EmitFlags.NoIndentation;
         node.name = typeof name === "string" ? createIdentifier(name) : name;
         return node;
     }
@@ -444,7 +444,7 @@ namespace ts {
         if (node.expression !== expression || node.name !== name) {
             const propertyAccess = createPropertyAccess(expression, name, /*location*/ node, node.flags);
             // Because we are updating existed propertyAccess we want to inherit its emitFlags instead of using default from createPropertyAccess
-            propertyAccess.emitFlags = node.emitFlags;
+            (propertyAccess.emitNode || (propertyAccess.emitNode = {})).flags = getEmitFlags(node);
             return updateNode(propertyAccess, node);
         }
         return node;
@@ -1551,7 +1551,7 @@ namespace ts {
         }
         else {
             const expression = isIdentifier(memberName) ? createPropertyAccess(target, memberName, location) : createElementAccess(target, memberName, location);
-            expression.emitFlags |= NodeEmitFlags.NoNestedSourceMaps;
+            (expression.emitNode || (expression.emitNode = {})).flags |= EmitFlags.NoNestedSourceMaps;
             return expression;
         }
     }
@@ -1744,7 +1744,7 @@ namespace ts {
         );
 
         // Mark this node as originally an async function
-        generatorFunc.emitFlags |= NodeEmitFlags.AsyncFunctionBody;
+        (generatorFunc.emitNode || (generatorFunc.emitNode = {})).flags |= EmitFlags.AsyncFunctionBody;
 
         return createCall(
             createHelperName(externalHelpersModuleName, "__awaiter"),
@@ -2222,7 +2222,7 @@ namespace ts {
                     target.push(startOnNewLine(createStatement(createLiteral("use strict"))));
                     foundUseStrict = true;
                 }
-                if (statement.emitFlags & NodeEmitFlags.CustomPrologue) {
+                if (getEmitFlags(statement) & EmitFlags.CustomPrologue) {
                     target.push(visitor ? visitNode(statement, visitor, isStatement) : statement);
                 }
                 else {
@@ -2643,14 +2643,28 @@ namespace ts {
     export function setOriginalNode<T extends Node>(node: T, original: Node): T {
         node.original = original;
         if (original) {
-            const { emitFlags, commentRange, sourceMapRange } = original;
-            if (emitFlags) node.emitFlags = emitFlags;
-            if (commentRange) node.commentRange = commentRange;
-            if (sourceMapRange) node.sourceMapRange = sourceMapRange;
+            const emitNode = original.emitNode;
+            if (emitNode) node.emitNode = mergeEmitNode(emitNode, node.emitNode);
         }
         return node;
     }
 
+    function mergeEmitNode(sourceEmitNode: EmitNode, destEmitNode: EmitNode) {
+        const { flags, commentRange, sourceMapRange, tokenSourceMapRanges } = sourceEmitNode;
+        if (!destEmitNode && (flags || commentRange || sourceMapRange || tokenSourceMapRanges)) destEmitNode = {};
+        if (flags) destEmitNode.flags = flags;
+        if (commentRange) destEmitNode.commentRange = commentRange;
+        if (sourceMapRange) destEmitNode.sourceMapRange = sourceMapRange;
+        if (tokenSourceMapRanges) destEmitNode.tokenSourceMapRanges = mergeTokenSourceMapRanges(tokenSourceMapRanges, destEmitNode.tokenSourceMapRanges);
+        return destEmitNode;
+    }
+
+    function mergeTokenSourceMapRanges(sourceRanges: Map<TextRange>, destRanges: Map<TextRange>) {
+        if (!destRanges) destRanges = createMap<TextRange>();
+        copyProperties(sourceRanges, destRanges);
+        return destRanges;
+    }
+
     export function setTextRange<T extends TextRange>(node: T, location: TextRange): T {
         if (location) {
             node.pos = location.pos;
diff --git a/src/compiler/transformer.ts b/src/compiler/transformer.ts
index 6242a2f2347..8c6fae458f0 100644
--- a/src/compiler/transformer.ts
+++ b/src/compiler/transformer.ts
@@ -30,11 +30,6 @@ namespace ts {
          */
         getSourceFiles(): SourceFile[];
 
-        /**
-         * Gets the TextRange to use for source maps for a token of a node.
-         */
-        getTokenSourceMapRange(node: Node, token: SyntaxKind): TextRange;
-
         /**
          * Determines whether expression substitutions are enabled for the provided node.
          */
@@ -75,46 +70,6 @@ namespace ts {
         getEmitResolver(): EmitResolver;
         getEmitHost(): EmitHost;
 
-        /**
-         * Gets flags used to customize later transformations or emit.
-         */
-        getNodeEmitFlags(node: Node): NodeEmitFlags;
-
-        /**
-         * Sets flags used to customize later transformations or emit.
-         */
-        setNodeEmitFlags<T extends Node>(node: T, flags: NodeEmitFlags): T;
-
-        /**
-         * Gets the TextRange to use for source maps for the node.
-         */
-        getSourceMapRange(node: Node): TextRange;
-
-        /**
-         * Sets the TextRange to use for source maps for the node.
-         */
-        setSourceMapRange<T extends Node>(node: T, range: TextRange): T;
-
-        /**
-         * Gets the TextRange to use for source maps for a token of a node.
-         */
-        getTokenSourceMapRange(node: Node, token: SyntaxKind): TextRange;
-
-        /**
-         * Sets the TextRange to use for source maps for a token of a node.
-         */
-        setTokenSourceMapRange<T extends Node>(node: T, token: SyntaxKind, range: TextRange): T;
-
-        /**
-         * Gets the TextRange to use for comments for the node.
-         */
-        getCommentRange(node: Node): TextRange;
-
-        /**
-         * Sets the TextRange to use for comments for the node.
-         */
-        setCommentRange<T extends Node>(node: T, range: TextRange): T;
-
         /**
          * Hoists a function declaration to the containing scope.
          */
@@ -187,12 +142,137 @@ namespace ts {
     }
 
     /**
-     * Tracks a monotonically increasing transformation id used to associate a node with a specific
-     * transformation. This ensures transient properties related to transformations can be safely
-     * stored on source tree nodes that may be reused across multiple transformations (such as
-     * with compile-on-save).
+     * Clears any EmitNode entries from parse-tree nodes.
+     * @param sourceFile A source file.
      */
-    let nextTransformId = 1;
+    export function disposeEmitNodes(sourceFile: SourceFile) {
+        // During transformation we may need to annotate a parse tree node with transient
+        // transformation properties. As parse tree nodes live longer than transformation
+        // nodes, we need to make sure we reclaim any memory allocated for custom ranges
+        // from these nodes to ensure we do not hold onto entire subtrees just for position
+        // information. We also need to reset these nodes to a pre-transformation state
+        // for incremental parsing scenarios so that we do not impact later emit.
+        sourceFile = getSourceFileOfNode(getParseTreeNode(sourceFile));
+        const emitNode = sourceFile && sourceFile.emitNode;
+        const annotatedNodes = emitNode && emitNode.annotatedNodes;
+        if (annotatedNodes) {
+            for (const node of annotatedNodes) {
+                node.emitNode = undefined;
+            }
+        }
+    }
+
+    /**
+     * Associates a node with the current transformation, initializing
+     * various transient transformation properties.
+     *
+     * @param node The node.
+     */
+    function getOrCreateEmitNode(node: Node) {
+        if (!node.emitNode) {
+            if (isParseTreeNode(node)) {
+                // To avoid holding onto transformation artifacts, we keep track of any
+                // parse tree node we are annotating. This allows us to clean them up after
+                // all transformations have completed.
+                if (node.kind === SyntaxKind.SourceFile) {
+                    return node.emitNode = { annotatedNodes: [node] };
+                }
+
+                const sourceFile = getSourceFileOfNode(node);
+                getOrCreateEmitNode(sourceFile).annotatedNodes.push(node);
+            }
+
+            node.emitNode = {};
+        }
+
+        return node.emitNode;
+    }
+
+    /**
+     * Gets flags that control emit behavior of a node.
+     *
+     * @param node The node.
+     */
+    export function getEmitFlags(node: Node) {
+        const emitNode = node.emitNode;
+        return emitNode && emitNode.flags;
+    }
+
+    /**
+     * Sets flags that control emit behavior of a node.
+     *
+     * @param node The node.
+     * @param emitFlags The NodeEmitFlags for the node.
+     */
+    export function setEmitFlags<T extends Node>(node: T, emitFlags: EmitFlags) {
+        getOrCreateEmitNode(node).flags = emitFlags;
+        return node;
+    }
+
+    /**
+     * Sets a custom text range to use when emitting source maps.
+     *
+     * @param node The node.
+     * @param range The text range.
+     */
+    export function setSourceMapRange<T extends Node>(node: T, range: TextRange) {
+        getOrCreateEmitNode(node).sourceMapRange = range;
+        return node;
+    }
+
+    /**
+     * Sets the TextRange to use for source maps for a token of a node.
+     *
+     * @param node The node.
+     * @param token The token.
+     * @param range The text range.
+     */
+    export function setTokenSourceMapRange<T extends Node>(node: T, token: SyntaxKind, range: TextRange) {
+        const emitNode = getOrCreateEmitNode(node);
+        const tokenSourceMapRanges = emitNode.tokenSourceMapRanges || (emitNode.tokenSourceMapRanges = createMap<TextRange>());
+        tokenSourceMapRanges[token] = range;
+        return node;
+    }
+
+    /**
+     * Sets a custom text range to use when emitting comments.
+     */
+    export function setCommentRange<T extends Node>(node: T, range: TextRange) {
+        getOrCreateEmitNode(node).commentRange = range;
+        return node;
+    }
+
+    /**
+     * Gets a custom text range to use when emitting comments.
+     *
+     * @param node The node.
+     */
+    export function getCommentRange(node: Node) {
+        const emitNode = node.emitNode;
+        return (emitNode && emitNode.commentRange) || node;
+    }
+
+    /**
+     * Gets a custom text range to use when emitting source maps.
+     *
+     * @param node The node.
+     */
+    export function getSourceMapRange(node: Node) {
+        const emitNode = node.emitNode;
+        return (emitNode && emitNode.sourceMapRange) || node;
+    }
+
+    /**
+     * Gets the TextRange to use for source maps for a token of a node.
+     *
+     * @param node The node.
+     * @param token The token.
+     */
+    export function getTokenSourceMapRange(node: Node, token: SyntaxKind) {
+        const emitNode = node.emitNode;
+        const tokenSourceMapRanges = emitNode && emitNode.tokenSourceMapRanges;
+        return tokenSourceMapRanges && tokenSourceMapRanges[token];
+    }
 
     /**
      * Transforms an array of SourceFiles by passing them through each transformer.
@@ -203,18 +283,10 @@ namespace ts {
      * @param transforms An array of Transformers.
      */
     export function transformFiles(resolver: EmitResolver, host: EmitHost, sourceFiles: SourceFile[], transformers: Transformer[]): TransformationResult {
-        const transformId = nextTransformId;
-        nextTransformId++;
-
-        const tokenSourceMapRanges = createMap<TextRange>();
         const lexicalEnvironmentVariableDeclarationsStack: VariableDeclaration[][] = [];
         const lexicalEnvironmentFunctionDeclarationsStack: FunctionDeclaration[][] = [];
         const enabledSyntaxKindFeatures = new Array<SyntaxKindFeatureFlags>(SyntaxKind.Count);
-        const parseTreeNodesWithAnnotations: Node[] = [];
 
-        let lastTokenSourceMapRangeNode: Node;
-        let lastTokenSourceMapRangeToken: SyntaxKind;
-        let lastTokenSourceMapRange: TextRange;
         let lexicalEnvironmentStackOffset = 0;
         let hoistedVariableDeclarations: VariableDeclaration[];
         let hoistedFunctionDeclarations: FunctionDeclaration[];
@@ -226,14 +298,6 @@ namespace ts {
             getCompilerOptions: () => host.getCompilerOptions(),
             getEmitResolver: () => resolver,
             getEmitHost: () => host,
-            getNodeEmitFlags,
-            setNodeEmitFlags,
-            getSourceMapRange,
-            setSourceMapRange,
-            getTokenSourceMapRange,
-            setTokenSourceMapRange,
-            getCommentRange,
-            setCommentRange,
             hoistVariableDeclaration,
             hoistFunctionDeclaration,
             startLexicalEnvironment,
@@ -257,7 +321,6 @@ namespace ts {
 
         return {
             getSourceFiles: () => transformed,
-            getTokenSourceMapRange,
             isSubstitutionEnabled,
             isEmitNotificationEnabled,
             onSubstituteNode: context.onSubstituteNode,
@@ -269,16 +332,9 @@ namespace ts {
                 // from these nodes to ensure we do not hold onto entire subtrees just for position
                 // information. We also need to reset these nodes to a pre-transformation state
                 // for incremental parsing scenarios so that we do not impact later emit.
-                for (const node of parseTreeNodesWithAnnotations) {
-                    if (node.transformId === transformId) {
-                        node.transformId = 0;
-                        node.emitFlags = 0;
-                        node.commentRange = undefined;
-                        node.sourceMapRange = undefined;
-                    }
+                for (const sourceFile of sourceFiles) {
+                    disposeEmitNodes(sourceFile);
                 }
-
-                parseTreeNodesWithAnnotations.length = 0;
             }
         };
 
@@ -333,7 +389,7 @@ namespace ts {
          */
         function isEmitNotificationEnabled(node: Node) {
             return (enabledSyntaxKindFeatures[node.kind] & SyntaxKindFeatureFlags.EmitNotifications) !== 0
-                || (getNodeEmitFlags(node) & NodeEmitFlags.AdviseOnEmitNode) !== 0;
+                || (getEmitFlags(node) & EmitFlags.AdviseOnEmitNode) !== 0;
         }
 
         /**
@@ -346,143 +402,6 @@ namespace ts {
             emit(node);
         }
 
-        /**
-         * Associates a node with the current transformation, initializing
-         * various transient transformation properties.
-         *
-         * @param node The node.
-         */
-        function beforeSetAnnotation(node: Node) {
-            if ((node.flags & NodeFlags.Synthesized) === 0 && node.transformId !== transformId) {
-                // To avoid holding onto transformation artifacts, we keep track of any
-                // parse tree node we are annotating. This allows us to clean them up after
-                // all transformations have completed.
-                parseTreeNodesWithAnnotations.push(node);
-                node.transformId = transformId;
-            }
-        }
-
-        /**
-         * Gets flags that control emit behavior of a node.
-         *
-         * If the node does not have its own NodeEmitFlags set, the node emit flags of its
-         * original pointer are used.
-         *
-         * @param node The node.
-         */
-        function getNodeEmitFlags(node: Node) {
-            return node.emitFlags;
-        }
-
-        /**
-         * Sets flags that control emit behavior of a node.
-         *
-         * @param node The node.
-         * @param emitFlags The NodeEmitFlags for the node.
-         */
-        function setNodeEmitFlags<T extends Node>(node: T, emitFlags: NodeEmitFlags) {
-            beforeSetAnnotation(node);
-            node.emitFlags = emitFlags;
-            return node;
-        }
-
-        /**
-         * Gets a custom text range to use when emitting source maps.
-         *
-         * If a node does not have its own custom source map text range, the custom source map
-         * text range of its original pointer is used.
-         *
-         * @param node The node.
-         */
-        function getSourceMapRange(node: Node) {
-            return node.sourceMapRange || node;
-        }
-
-        /**
-         * Sets a custom text range to use when emitting source maps.
-         *
-         * @param node The node.
-         * @param range The text range.
-         */
-        function setSourceMapRange<T extends Node>(node: T, range: TextRange) {
-            beforeSetAnnotation(node);
-            node.sourceMapRange = range;
-            return node;
-        }
-
-        /**
-         * Gets the TextRange to use for source maps for a token of a node.
-         *
-         * If a node does not have its own custom source map text range for a token, the custom
-         * source map text range for the token of its original pointer is used.
-         *
-         * @param node The node.
-         * @param token The token.
-         */
-        function getTokenSourceMapRange(node: Node, token: SyntaxKind) {
-            // As a performance optimization, use the cached value of the most recent node.
-            // This helps for cases where this function is called repeatedly for the same node.
-            if (lastTokenSourceMapRangeNode === node && lastTokenSourceMapRangeToken === token) {
-                return lastTokenSourceMapRange;
-            }
-
-            // Get the custom token source map range for a node or from one of its original nodes.
-            // Custom token ranges are not stored on the node to avoid the GC burden.
-            let range: TextRange;
-            let current = node;
-            while (current) {
-                range = current.id ? tokenSourceMapRanges[current.id + "-" + token] : undefined;
-                if (range !== undefined) {
-                    break;
-                }
-
-                current = current.original;
-            }
-
-            // Cache the most recently requested value.
-            lastTokenSourceMapRangeNode = node;
-            lastTokenSourceMapRangeToken = token;
-            lastTokenSourceMapRange = range;
-            return range;
-        }
-
-        /**
-         * Sets the TextRange to use for source maps for a token of a node.
-         *
-         * @param node The node.
-         * @param token The token.
-         * @param range The text range.
-         */
-        function setTokenSourceMapRange<T extends Node>(node: T, token: SyntaxKind, range: TextRange) {
-            // Cache the most recently requested value.
-            lastTokenSourceMapRangeNode = node;
-            lastTokenSourceMapRangeToken = token;
-            lastTokenSourceMapRange = range;
-            tokenSourceMapRanges[getNodeId(node) + "-" + token] = range;
-            return node;
-        }
-
-        /**
-         * Gets a custom text range to use when emitting comments.
-         *
-         * If a node does not have its own custom source map text range, the custom source map
-         * text range of its original pointer is used.
-         *
-         * @param node The node.
-         */
-        function getCommentRange(node: Node) {
-            return node.commentRange || node;
-        }
-
-        /**
-         * Sets a custom text range to use when emitting comments.
-         */
-        function setCommentRange<T extends Node>(node: T, range: TextRange) {
-            beforeSetAnnotation(node);
-            node.commentRange = range;
-            return node;
-        }
-
         /**
          * Records a hoisted variable declaration for the provided name within a lexical environment.
          */
@@ -563,70 +482,4 @@ namespace ts {
             return statements;
         }
     }
-
-    /**
-     * High-order function, creates a function that executes a function composition.
-     * For example, `chain(a, b)` is the equivalent of `x => ((a', b') => y => b'(a'(y)))(a(x), b(x))`
-     *
-     * @param args The functions to chain.
-     */
-    function chain<T, U>(...args: ((t: T) => (u: U) => U)[]): (t: T) => (u: U) => U;
-    function chain<T, U>(a: (t: T) => (u: U) => U, b: (t: T) => (u: U) => U, c: (t: T) => (u: U) => U, d: (t: T) => (u: U) => U, e: (t: T) => (u: U) => U): (t: T) => (u: U) => U {
-        if (e) {
-            const args: ((t: T) => (u: U) => U)[] = [];
-            for (let i = 0; i < arguments.length; i++) {
-                args[i] = arguments[i];
-            }
-
-            return t => compose(...map(args, f => f(t)));
-        }
-        else if (d) {
-            return t => compose(a(t), b(t), c(t), d(t));
-        }
-        else if (c) {
-            return t => compose(a(t), b(t), c(t));
-        }
-        else if (b) {
-            return t => compose(a(t), b(t));
-        }
-        else if (a) {
-            return t => compose(a(t));
-        }
-        else {
-            return t => u => u;
-        }
-    }
-
-    /**
-     * High-order function, composes functions. Note that functions are composed inside-out;
-     * for example, `compose(a, b)` is the equivalent of `x => b(a(x))`.
-     *
-     * @param args The functions to compose.
-     */
-    function compose<T>(...args: ((t: T) => T)[]): (t: T) => T;
-    function compose<T>(a: (t: T) => T, b: (t: T) => T, c: (t: T) => T, d: (t: T) => T, e: (t: T) => T): (t: T) => T {
-        if (e) {
-            const args: ((t: T) => T)[] = [];
-            for (let i = 0; i < arguments.length; i++) {
-                args[i] = arguments[i];
-            }
-
-            return t => reduceLeft<(t: T) => T, T>(args, (u, f) => f(u), t);
-        }
-        else if (d) {
-            return t => d(c(b(a(t))));
-        }
-        else if (c) {
-            return t => c(b(a(t)));
-        }
-        else if (b) {
-            return t => b(a(t));
-        }
-        else if (a) {
-            return t => a(t);
-        }
-        else {
-            return t => t;
-        }
-    }
 }
\ No newline at end of file
diff --git a/src/compiler/transformers/destructuring.ts b/src/compiler/transformers/destructuring.ts
index c6079ee1378..ac433647f55 100644
--- a/src/compiler/transformers/destructuring.ts
+++ b/src/compiler/transformers/destructuring.ts
@@ -66,7 +66,7 @@ namespace ts {
 
             // NOTE: this completely disables source maps, but aligns with the behavior of
             //       `emitAssignment` in the old emitter.
-            context.setNodeEmitFlags(expression, NodeEmitFlags.NoNestedSourceMaps);
+            setEmitFlags(expression, EmitFlags.NoNestedSourceMaps);
 
             aggregateTransformFlags(expression);
             expressions.push(expression);
@@ -102,7 +102,7 @@ namespace ts {
 
             // NOTE: this completely disables source maps, but aligns with the behavior of
             //       `emitAssignment` in the old emitter.
-            context.setNodeEmitFlags(declaration, NodeEmitFlags.NoNestedSourceMaps);
+            setEmitFlags(declaration, EmitFlags.NoNestedSourceMaps);
 
             aggregateTransformFlags(declaration);
             declarations.push(declaration);
@@ -139,7 +139,7 @@ namespace ts {
 
             // NOTE: this completely disables source maps, but aligns with the behavior of
             //       `emitAssignment` in the old emitter.
-            context.setNodeEmitFlags(declaration, NodeEmitFlags.NoNestedSourceMaps);
+            setEmitFlags(declaration, EmitFlags.NoNestedSourceMaps);
 
             declarations.push(declaration);
             aggregateTransformFlags(declaration);
@@ -192,7 +192,7 @@ namespace ts {
 
             // NOTE: this completely disables source maps, but aligns with the behavior of
             //       `emitAssignment` in the old emitter.
-            context.setNodeEmitFlags(expression, NodeEmitFlags.NoNestedSourceMaps);
+            setEmitFlags(expression, EmitFlags.NoNestedSourceMaps);
 
             pendingAssignments.push(expression);
             return expression;
@@ -252,8 +252,8 @@ namespace ts {
             }
             else {
                 const name = getMutableClone(<Identifier>target);
-                context.setSourceMapRange(name, target);
-                context.setCommentRange(name, target);
+                setSourceMapRange(name, target);
+                setCommentRange(name, target);
                 emitAssignment(name, value, location, /*original*/ undefined);
             }
         }
diff --git a/src/compiler/transformers/es6.ts b/src/compiler/transformers/es6.ts
index 51a6a088fb7..eda0d03c704 100644
--- a/src/compiler/transformers/es6.ts
+++ b/src/compiler/transformers/es6.ts
@@ -144,13 +144,6 @@ namespace ts {
             startLexicalEnvironment,
             endLexicalEnvironment,
             hoistVariableDeclaration,
-            getNodeEmitFlags,
-            setNodeEmitFlags,
-            getCommentRange,
-            setCommentRange,
-            getSourceMapRange,
-            setSourceMapRange,
-            setTokenSourceMapRange,
         } = context;
 
         const resolver = context.getEmitResolver();
@@ -190,6 +183,10 @@ namespace ts {
         return transformSourceFile;
 
         function transformSourceFile(node: SourceFile) {
+            if (isDeclarationFile(node)) {
+                return node;
+            }
+
             currentSourceFile = node;
             currentText = node.text;
             return visitNode(node, visitor, isSourceFile);
@@ -427,7 +424,7 @@ namespace ts {
                     case SyntaxKind.SetAccessor:
                     case SyntaxKind.FunctionDeclaration:
                         containingNonArrowFunction = <FunctionLikeDeclaration>currentParent;
-                        if (!(containingNonArrowFunction.emitFlags & NodeEmitFlags.AsyncFunctionBody)) {
+                        if (!(getEmitFlags(containingNonArrowFunction) & EmitFlags.AsyncFunctionBody)) {
                             superScopeContainer = containingNonArrowFunction;
                         }
                         break;
@@ -669,19 +666,19 @@ namespace ts {
             // To preserve the behavior of the old emitter, we explicitly indent
             // the body of the function here if it was requested in an earlier
             // transformation.
-            if (getNodeEmitFlags(node) & NodeEmitFlags.Indented) {
-                setNodeEmitFlags(classFunction, NodeEmitFlags.Indented);
+            if (getEmitFlags(node) & EmitFlags.Indented) {
+                setEmitFlags(classFunction, EmitFlags.Indented);
             }
 
             // "inner" and "outer" below are added purely to preserve source map locations from
             // the old emitter
             const inner = createPartiallyEmittedExpression(classFunction);
             inner.end = node.end;
-            setNodeEmitFlags(inner, NodeEmitFlags.NoComments);
+            setEmitFlags(inner, EmitFlags.NoComments);
 
             const outer = createPartiallyEmittedExpression(inner);
             outer.end = skipTrivia(currentText, node.pos);
-            setNodeEmitFlags(outer, NodeEmitFlags.NoComments);
+            setEmitFlags(outer, EmitFlags.NoComments);
 
             return createParen(
                 createCall(
@@ -715,17 +712,17 @@ namespace ts {
             // emit with the original emitter.
             const outer = createPartiallyEmittedExpression(localName);
             outer.end = closingBraceLocation.end;
-            setNodeEmitFlags(outer, NodeEmitFlags.NoComments);
+            setEmitFlags(outer, EmitFlags.NoComments);
 
             const statement = createReturn(outer);
             statement.pos = closingBraceLocation.pos;
-            setNodeEmitFlags(statement, NodeEmitFlags.NoComments | NodeEmitFlags.NoTokenSourceMaps);
+            setEmitFlags(statement, EmitFlags.NoComments | EmitFlags.NoTokenSourceMaps);
             statements.push(statement);
 
             addRange(statements, endLexicalEnvironment());
 
             const block = createBlock(createNodeArray(statements, /*location*/ node.members), /*location*/ undefined, /*multiLine*/ true);
-            setNodeEmitFlags(block, NodeEmitFlags.NoComments);
+            setEmitFlags(block, EmitFlags.NoComments);
             return block;
         }
 
@@ -828,7 +825,7 @@ namespace ts {
             );
 
             if (!constructor) {
-                setNodeEmitFlags(block, NodeEmitFlags.NoComments);
+                setEmitFlags(block, EmitFlags.NoComments);
             }
 
             return block;
@@ -965,27 +962,27 @@ namespace ts {
             // of an initializer, we must emit that expression to preserve side effects.
             if (name.elements.length > 0) {
                 statements.push(
-                    setNodeEmitFlags(
+                    setEmitFlags(
                         createVariableStatement(
                             /*modifiers*/ undefined,
                             createVariableDeclarationList(
                                 flattenParameterDestructuring(context, parameter, temp, visitor)
                             )
                         ),
-                        NodeEmitFlags.CustomPrologue
+                        EmitFlags.CustomPrologue
                     )
                 );
             }
             else if (initializer) {
                 statements.push(
-                    setNodeEmitFlags(
+                    setEmitFlags(
                         createStatement(
                             createAssignment(
                                 temp,
                                 visitNode(initializer, visitor, isExpression)
                             )
                         ),
-                        NodeEmitFlags.CustomPrologue
+                        EmitFlags.CustomPrologue
                     )
                 );
             }
@@ -1006,23 +1003,23 @@ namespace ts {
                     getSynthesizedClone(name),
                     createVoidZero()
                 ),
-                setNodeEmitFlags(
+                setEmitFlags(
                     createBlock([
                         createStatement(
                             createAssignment(
-                                setNodeEmitFlags(getMutableClone(name), NodeEmitFlags.NoSourceMap),
-                                setNodeEmitFlags(initializer, NodeEmitFlags.NoSourceMap | getNodeEmitFlags(initializer)),
+                                setEmitFlags(getMutableClone(name), EmitFlags.NoSourceMap),
+                                setEmitFlags(initializer, EmitFlags.NoSourceMap | getEmitFlags(initializer)),
                                 /*location*/ parameter
                             )
                         )
                     ], /*location*/ parameter),
-                    NodeEmitFlags.SingleLine | NodeEmitFlags.NoTrailingSourceMap | NodeEmitFlags.NoTokenSourceMaps
+                    EmitFlags.SingleLine | EmitFlags.NoTrailingSourceMap | EmitFlags.NoTokenSourceMaps
                 ),
                 /*elseStatement*/ undefined,
                 /*location*/ parameter
             );
             statement.startsOnNewLine = true;
-            setNodeEmitFlags(statement, NodeEmitFlags.NoTokenSourceMaps | NodeEmitFlags.NoTrailingSourceMap | NodeEmitFlags.CustomPrologue);
+            setEmitFlags(statement, EmitFlags.NoTokenSourceMaps | EmitFlags.NoTrailingSourceMap | EmitFlags.CustomPrologue);
             statements.push(statement);
         }
 
@@ -1055,7 +1052,7 @@ namespace ts {
 
             // `declarationName` is the name of the local declaration for the parameter.
             const declarationName = getMutableClone(<Identifier>parameter.name);
-            setNodeEmitFlags(declarationName, NodeEmitFlags.NoSourceMap);
+            setEmitFlags(declarationName, EmitFlags.NoSourceMap);
 
             // `expressionName` is the name of the parameter used in expressions.
             const expressionName = getSynthesizedClone(<Identifier>parameter.name);
@@ -1064,7 +1061,7 @@ namespace ts {
 
             // var param = [];
             statements.push(
-                setNodeEmitFlags(
+                setEmitFlags(
                     createVariableStatement(
                         /*modifiers*/ undefined,
                         createVariableDeclarationList([
@@ -1076,7 +1073,7 @@ namespace ts {
                         ]),
                         /*location*/ parameter
                     ),
-                    NodeEmitFlags.CustomPrologue
+                    EmitFlags.CustomPrologue
                 )
             );
 
@@ -1109,7 +1106,7 @@ namespace ts {
                 ])
             );
 
-            setNodeEmitFlags(forStatement, NodeEmitFlags.CustomPrologue);
+            setEmitFlags(forStatement, EmitFlags.CustomPrologue);
             startOnNewLine(forStatement);
             statements.push(forStatement);
         }
@@ -1134,7 +1131,7 @@ namespace ts {
                     ])
                 );
 
-                setNodeEmitFlags(captureThisStatement, NodeEmitFlags.NoComments | NodeEmitFlags.CustomPrologue);
+                setEmitFlags(captureThisStatement, EmitFlags.NoComments | EmitFlags.CustomPrologue);
                 setSourceMapRange(captureThisStatement, node);
                 statements.push(captureThisStatement);
             }
@@ -1198,7 +1195,7 @@ namespace ts {
             const sourceMapRange = getSourceMapRange(member);
 
             const func = transformFunctionLikeToExpression(member, /*location*/ member, /*name*/ undefined);
-            setNodeEmitFlags(func, NodeEmitFlags.NoComments);
+            setEmitFlags(func, EmitFlags.NoComments);
             setSourceMapRange(func, sourceMapRange);
 
             const statement = createStatement(
@@ -1219,7 +1216,7 @@ namespace ts {
             // The location for the statement is used to emit comments only.
             // No source map should be emitted for this statement to align with the
             // old emitter.
-            setNodeEmitFlags(statement, NodeEmitFlags.NoSourceMap);
+            setEmitFlags(statement, EmitFlags.NoSourceMap);
             return statement;
         }
 
@@ -1238,7 +1235,7 @@ namespace ts {
             // The location for the statement is used to emit source maps only.
             // No comments should be emitted for this statement to align with the
             // old emitter.
-            setNodeEmitFlags(statement, NodeEmitFlags.NoComments);
+            setEmitFlags(statement, EmitFlags.NoComments);
             return statement;
         }
 
@@ -1252,11 +1249,11 @@ namespace ts {
             // To align with source maps in the old emitter, the receiver and property name
             // arguments are both mapped contiguously to the accessor name.
             const target = getMutableClone(receiver);
-            setNodeEmitFlags(target, NodeEmitFlags.NoComments | NodeEmitFlags.NoTrailingSourceMap);
+            setEmitFlags(target, EmitFlags.NoComments | EmitFlags.NoTrailingSourceMap);
             setSourceMapRange(target, firstAccessor.name);
 
             const propertyName = createExpressionForPropertyName(visitNode(firstAccessor.name, visitor, isPropertyName));
-            setNodeEmitFlags(propertyName, NodeEmitFlags.NoComments | NodeEmitFlags.NoLeadingSourceMap);
+            setEmitFlags(propertyName, EmitFlags.NoComments | EmitFlags.NoLeadingSourceMap);
             setSourceMapRange(propertyName, firstAccessor.name);
 
             const properties: ObjectLiteralElement[] = [];
@@ -1312,7 +1309,7 @@ namespace ts {
             const func = transformFunctionLikeToExpression(node, /*location*/ node, /*name*/ undefined);
 
             useCapturedThis = savedUseCapturedThis;
-            setNodeEmitFlags(func, NodeEmitFlags.CapturesThis);
+            setEmitFlags(func, EmitFlags.CapturesThis);
             return func;
         }
 
@@ -1437,7 +1434,7 @@ namespace ts {
 
                 const expression = visitNode(body, visitor, isExpression);
                 const returnStatement = createReturn(expression, /*location*/ body);
-                setNodeEmitFlags(returnStatement, NodeEmitFlags.NoTokenSourceMaps | NodeEmitFlags.NoTrailingSourceMap | NodeEmitFlags.NoTrailingComments);
+                setEmitFlags(returnStatement, EmitFlags.NoTokenSourceMaps | EmitFlags.NoTrailingSourceMap | EmitFlags.NoTrailingComments);
                 statements.push(returnStatement);
 
                 // To align with the source map emit for the old emitter, we set a custom
@@ -1455,7 +1452,7 @@ namespace ts {
 
             const block = createBlock(createNodeArray(statements, statementsLocation), node.body, multiLine);
             if (!multiLine && singleLine) {
-                setNodeEmitFlags(block, NodeEmitFlags.SingleLine);
+                setEmitFlags(block, EmitFlags.SingleLine);
             }
 
             if (closeBraceLocation) {
@@ -1875,7 +1872,7 @@ namespace ts {
             }
 
             // The old emitter does not emit source maps for the expression
-            setNodeEmitFlags(expression, NodeEmitFlags.NoSourceMap | getNodeEmitFlags(expression));
+            setEmitFlags(expression, EmitFlags.NoSourceMap | getEmitFlags(expression));
 
             // The old emitter does not emit source maps for the block.
             // We add the location to preserve comments.
@@ -1884,7 +1881,7 @@ namespace ts {
                 /*location*/ bodyLocation
             );
 
-            setNodeEmitFlags(body, NodeEmitFlags.NoSourceMap | NodeEmitFlags.NoTokenSourceMaps);
+            setEmitFlags(body, EmitFlags.NoSourceMap | EmitFlags.NoTokenSourceMaps);
 
             const forStatement = createFor(
                 createVariableDeclarationList([
@@ -1902,7 +1899,7 @@ namespace ts {
             );
 
             // Disable trailing source maps for the OpenParenToken to align source map emit with the old emitter.
-            setNodeEmitFlags(forStatement, NodeEmitFlags.NoTokenTrailingSourceMaps);
+            setEmitFlags(forStatement, EmitFlags.NoTokenTrailingSourceMaps);
             return forStatement;
         }
 
@@ -1938,13 +1935,13 @@ namespace ts {
             const expressions: Expression[] = [];
             const assignment = createAssignment(
                 temp,
-                setNodeEmitFlags(
+                setEmitFlags(
                     createObjectLiteral(
                         visitNodes(properties, visitor, isObjectLiteralElement, 0, numInitialProperties),
                         /*location*/ undefined,
                         node.multiLine
                     ),
-                    NodeEmitFlags.Indented
+                    EmitFlags.Indented
                 )
             );
             if (node.multiLine) {
@@ -2067,16 +2064,16 @@ namespace ts {
 
             const isAsyncBlockContainingAwait =
                 containingNonArrowFunction
-                && (containingNonArrowFunction.emitFlags & NodeEmitFlags.AsyncFunctionBody) !== 0
+                && (getEmitFlags(containingNonArrowFunction) & EmitFlags.AsyncFunctionBody) !== 0
                 && (node.statement.transformFlags & TransformFlags.ContainsYield) !== 0;
 
-            let loopBodyFlags: NodeEmitFlags = 0;
+            let loopBodyFlags: EmitFlags = 0;
             if (currentState.containsLexicalThis) {
-                loopBodyFlags |= NodeEmitFlags.CapturesThis;
+                loopBodyFlags |= EmitFlags.CapturesThis;
             }
 
             if (isAsyncBlockContainingAwait) {
-                loopBodyFlags |= NodeEmitFlags.AsyncFunctionBody;
+                loopBodyFlags |= EmitFlags.AsyncFunctionBody;
             }
 
             const convertedLoopVariable =
@@ -2087,7 +2084,7 @@ namespace ts {
                             createVariableDeclaration(
                                 functionName,
                                 /*type*/ undefined,
-                                setNodeEmitFlags(
+                                setEmitFlags(
                                     createFunctionExpression(
                                         isAsyncBlockContainingAwait ? createToken(SyntaxKind.AsteriskToken) : undefined,
                                         /*name*/ undefined,
@@ -2480,7 +2477,7 @@ namespace ts {
             // Methods with computed property names are handled in visitObjectLiteralExpression.
             Debug.assert(!isComputedPropertyName(node.name));
             const functionExpression = transformFunctionLikeToExpression(node, /*location*/ moveRangePos(node, -1), /*name*/ undefined);
-            setNodeEmitFlags(functionExpression, NodeEmitFlags.NoLeadingComments | getNodeEmitFlags(functionExpression));
+            setEmitFlags(functionExpression, EmitFlags.NoLeadingComments | getEmitFlags(functionExpression));
             return createPropertyAssignment(
                 node.name,
                 functionExpression,
@@ -2861,7 +2858,7 @@ namespace ts {
             if (enabledSubstitutions & ES6SubstitutionFlags.CapturedThis && isFunctionLike(node)) {
                 // If we are tracking a captured `this`, push a bit that indicates whether the
                 // containing function is an arrow function.
-                useCapturedThis = (getNodeEmitFlags(node) & NodeEmitFlags.CapturesThis) !== 0;
+                useCapturedThis = (getEmitFlags(node) & EmitFlags.CapturesThis) !== 0;
             }
 
             previousOnEmitNode(node, emit);
@@ -3012,7 +3009,7 @@ namespace ts {
          * @param allowSourceMaps A value indicating whether source maps may be emitted for the name.
          */
         function getLocalName(node: ClassDeclaration | ClassExpression | FunctionDeclaration, allowComments?: boolean, allowSourceMaps?: boolean) {
-            return getDeclarationName(node, allowComments, allowSourceMaps, NodeEmitFlags.LocalName);
+            return getDeclarationName(node, allowComments, allowSourceMaps, EmitFlags.LocalName);
         }
 
         /**
@@ -3021,18 +3018,18 @@ namespace ts {
          * @param node The declaration.
          * @param allowComments Allow comments for the name.
          */
-        function getDeclarationName(node: DeclarationStatement | ClassExpression, allowComments?: boolean, allowSourceMaps?: boolean, emitFlags?: NodeEmitFlags) {
+        function getDeclarationName(node: DeclarationStatement | ClassExpression, allowComments?: boolean, allowSourceMaps?: boolean, emitFlags?: EmitFlags) {
             if (node.name && !isGeneratedIdentifier(node.name)) {
                 const name = getMutableClone(node.name);
-                emitFlags |= getNodeEmitFlags(node.name);
+                emitFlags |= getEmitFlags(node.name);
                 if (!allowSourceMaps) {
-                    emitFlags |= NodeEmitFlags.NoSourceMap;
+                    emitFlags |= EmitFlags.NoSourceMap;
                 }
                 if (!allowComments) {
-                    emitFlags |= NodeEmitFlags.NoComments;
+                    emitFlags |= EmitFlags.NoComments;
                 }
                 if (emitFlags) {
-                    setNodeEmitFlags(name, emitFlags);
+                    setEmitFlags(name, emitFlags);
                 }
                 return name;
             }
diff --git a/src/compiler/transformers/es7.ts b/src/compiler/transformers/es7.ts
index 5d848bc608b..4d5e96134c4 100644
--- a/src/compiler/transformers/es7.ts
+++ b/src/compiler/transformers/es7.ts
@@ -9,6 +9,10 @@ namespace ts {
         return transformSourceFile;
 
         function transformSourceFile(node: SourceFile) {
+            if (isDeclarationFile(node)) {
+                return node;
+            }
+
             return visitEachChild(node, visitor, context);
         }
 
diff --git a/src/compiler/transformers/generators.ts b/src/compiler/transformers/generators.ts
index d1e2b6033a6..d6a30a81d61 100644
--- a/src/compiler/transformers/generators.ts
+++ b/src/compiler/transformers/generators.ts
@@ -231,9 +231,6 @@ namespace ts {
             endLexicalEnvironment,
             hoistFunctionDeclaration,
             hoistVariableDeclaration,
-            setSourceMapRange,
-            setCommentRange,
-            setNodeEmitFlags
         } = context;
 
         const compilerOptions = context.getCompilerOptions();
@@ -294,6 +291,10 @@ namespace ts {
         return transformSourceFile;
 
         function transformSourceFile(node: SourceFile) {
+            if (isDeclarationFile(node)) {
+                return node;
+            }
+
             if (node.transformFlags & TransformFlags.ContainsGenerator) {
                 currentSourceFile = node;
                 node = visitEachChild(node, visitor, context);
@@ -444,7 +445,7 @@ namespace ts {
          */
         function visitFunctionDeclaration(node: FunctionDeclaration): Statement {
             // Currently, we only support generators that were originally async functions.
-            if (node.asteriskToken && node.emitFlags & NodeEmitFlags.AsyncFunctionBody) {
+            if (node.asteriskToken && getEmitFlags(node) & EmitFlags.AsyncFunctionBody) {
                 node = setOriginalNode(
                     createFunctionDeclaration(
                         /*decorators*/ undefined,
@@ -492,7 +493,7 @@ namespace ts {
          */
         function visitFunctionExpression(node: FunctionExpression): Expression {
             // Currently, we only support generators that were originally async functions.
-            if (node.asteriskToken && node.emitFlags & NodeEmitFlags.AsyncFunctionBody) {
+            if (node.asteriskToken && getEmitFlags(node) & EmitFlags.AsyncFunctionBody) {
                 node = setOriginalNode(
                     createFunctionExpression(
                         /*asteriskToken*/ undefined,
@@ -2580,7 +2581,7 @@ namespace ts {
                 /*typeArguments*/ undefined,
                 [
                     createThis(),
-                    setNodeEmitFlags(
+                    setEmitFlags(
                         createFunctionExpression(
                             /*asteriskToken*/ undefined,
                             /*name*/ undefined,
@@ -2593,7 +2594,7 @@ namespace ts {
                                 /*multiLine*/ buildResult.length > 0
                             )
                         ),
-                        NodeEmitFlags.ReuseTempVariableScope
+                        EmitFlags.ReuseTempVariableScope
                     )
                 ]
             );
diff --git a/src/compiler/transformers/jsx.ts b/src/compiler/transformers/jsx.ts
index 9e6aa507cce..95a4016bb0a 100644
--- a/src/compiler/transformers/jsx.ts
+++ b/src/compiler/transformers/jsx.ts
@@ -16,6 +16,10 @@ namespace ts {
          * @param node A SourceFile node.
          */
         function transformSourceFile(node: SourceFile) {
+            if (isDeclarationFile(node)) {
+                return node;
+            }
+
             currentSourceFile = node;
             node = visitEachChild(node, visitor, context);
             currentSourceFile = undefined;
diff --git a/src/compiler/transformers/module/es6.ts b/src/compiler/transformers/module/es6.ts
index 2716165f2d3..09a2890727c 100644
--- a/src/compiler/transformers/module/es6.ts
+++ b/src/compiler/transformers/module/es6.ts
@@ -12,6 +12,10 @@ namespace ts {
         return transformSourceFile;
 
         function transformSourceFile(node: SourceFile) {
+            if (isDeclarationFile(node)) {
+                return node;
+            }
+
             if (isExternalModule(node) || compilerOptions.isolatedModules) {
                 currentSourceFile = node;
                 return visitEachChild(node, visitor, context);
diff --git a/src/compiler/transformers/module/module.ts b/src/compiler/transformers/module/module.ts
index 9abd91b47c8..286ef967288 100644
--- a/src/compiler/transformers/module/module.ts
+++ b/src/compiler/transformers/module/module.ts
@@ -15,9 +15,6 @@ namespace ts {
             startLexicalEnvironment,
             endLexicalEnvironment,
             hoistVariableDeclaration,
-            setNodeEmitFlags,
-            getNodeEmitFlags,
-            setSourceMapRange,
         } = context;
 
         const compilerOptions = context.getCompilerOptions();
@@ -54,6 +51,10 @@ namespace ts {
          * @param node The SourceFile node.
          */
         function transformSourceFile(node: SourceFile) {
+            if (isDeclarationFile(node)) {
+                return node;
+            }
+
             if (isExternalModule(node) || compilerOptions.isolatedModules) {
                 currentSourceFile = node;
 
@@ -92,7 +93,7 @@ namespace ts {
 
             const updated = updateSourceFile(node, statements);
             if (hasExportStarsToExportValues) {
-                setNodeEmitFlags(updated, NodeEmitFlags.EmitExportStar | getNodeEmitFlags(node));
+                setEmitFlags(updated, EmitFlags.EmitExportStar | getEmitFlags(node));
             }
 
             return updated;
@@ -116,7 +117,7 @@ namespace ts {
          */
         function transformUMDModule(node: SourceFile) {
             const define = createIdentifier("define");
-            setNodeEmitFlags(define, NodeEmitFlags.UMDDefine);
+            setEmitFlags(define, EmitFlags.UMDDefine);
             return transformAsynchronousModule(node, define, /*moduleName*/ undefined, /*includeNonAmdDependencies*/ false);
         }
 
@@ -220,7 +221,7 @@ namespace ts {
             if (hasExportStarsToExportValues) {
                 // If we have any `export * from ...` declarations
                 // we need to inform the emitter to add the __export helper.
-                setNodeEmitFlags(body, NodeEmitFlags.EmitExportStar);
+                setEmitFlags(body, EmitFlags.EmitExportStar);
             }
 
             return body;
@@ -234,7 +235,7 @@ namespace ts {
                         /*location*/ exportEquals
                     );
 
-                    setNodeEmitFlags(statement, NodeEmitFlags.NoTokenSourceMaps | NodeEmitFlags.NoComments);
+                    setEmitFlags(statement, EmitFlags.NoTokenSourceMaps | EmitFlags.NoComments);
                     statements.push(statement);
                 }
                 else {
@@ -249,7 +250,7 @@ namespace ts {
                         /*location*/ exportEquals
                     );
 
-                    setNodeEmitFlags(statement, NodeEmitFlags.NoComments);
+                    setEmitFlags(statement, EmitFlags.NoComments);
                     statements.push(statement);
                 }
             }
@@ -388,7 +389,7 @@ namespace ts {
 
             // Set emitFlags on the name of the importEqualsDeclaration
             // This is so the printer will not substitute the identifier
-            setNodeEmitFlags(node.name, NodeEmitFlags.NoSubstitution);
+            setEmitFlags(node.name, EmitFlags.NoSubstitution);
             const statements: Statement[] = [];
             if (moduleKind !== ModuleKind.AMD) {
                 if (hasModifier(node, ModifierFlags.Export)) {
@@ -598,7 +599,7 @@ namespace ts {
             }
             else {
                 statements.push(
-                    createExportStatement(node.name, setNodeEmitFlags(getSynthesizedClone(node.name), NodeEmitFlags.LocalName), /*location*/ node)
+                    createExportStatement(node.name, setEmitFlags(getSynthesizedClone(node.name), EmitFlags.LocalName), /*location*/ node)
                 );
             }
         }
@@ -813,7 +814,7 @@ namespace ts {
                 )],
                     /*location*/ node
             );
-            setNodeEmitFlags(transformedStatement, NodeEmitFlags.NoComments);
+            setEmitFlags(transformedStatement, EmitFlags.NoComments);
             statements.push(transformedStatement);
         }
 
@@ -890,7 +891,7 @@ namespace ts {
             // If the left-hand-side of the binaryExpression is an identifier and its is export through export Specifier
             if (isIdentifier(left) && isAssignmentOperator(node.operatorToken.kind)) {
                 if (bindingNameExportSpecifiersMap && hasProperty(bindingNameExportSpecifiersMap, left.text)) {
-                    setNodeEmitFlags(node, NodeEmitFlags.NoSubstitution);
+                    setEmitFlags(node, EmitFlags.NoSubstitution);
                     let nestedExportAssignment: BinaryExpression;
                     for (const specifier of bindingNameExportSpecifiersMap[left.text]) {
                         nestedExportAssignment = nestedExportAssignment ?
@@ -910,7 +911,7 @@ namespace ts {
             const operand = node.operand;
             if (isIdentifier(operand) && bindingNameExportSpecifiersForFileMap) {
                 if (bindingNameExportSpecifiersMap && hasProperty(bindingNameExportSpecifiersMap, operand.text)) {
-                    setNodeEmitFlags(node, NodeEmitFlags.NoSubstitution);
+                    setEmitFlags(node, EmitFlags.NoSubstitution);
                     let transformedUnaryExpression: BinaryExpression;
                     if (node.kind === SyntaxKind.PostfixUnaryExpression) {
                         transformedUnaryExpression = createBinary(
@@ -920,7 +921,7 @@ namespace ts {
                             /*location*/ node
                         );
                         // We have to set no substitution flag here to prevent visit the binary expression and substitute it again as we will preform all necessary substitution in here
-                        setNodeEmitFlags(transformedUnaryExpression, NodeEmitFlags.NoSubstitution);
+                        setEmitFlags(transformedUnaryExpression, EmitFlags.NoSubstitution);
                     }
                     let nestedExportAssignment: BinaryExpression;
                     for (const specifier of bindingNameExportSpecifiersMap[operand.text]) {
@@ -935,9 +936,9 @@ namespace ts {
         }
 
         function trySubstituteExportedName(node: Identifier) {
-            const emitFlags = getNodeEmitFlags(node);
-            if ((emitFlags & NodeEmitFlags.LocalName) === 0) {
-                const container = resolver.getReferencedExportContainer(node, (emitFlags & NodeEmitFlags.ExportName) !== 0);
+            const emitFlags = getEmitFlags(node);
+            if ((emitFlags & EmitFlags.LocalName) === 0) {
+                const container = resolver.getReferencedExportContainer(node, (emitFlags & EmitFlags.ExportName) !== 0);
                 if (container) {
                     if (container.kind === SyntaxKind.SourceFile) {
                         return createPropertyAccess(
@@ -953,7 +954,7 @@ namespace ts {
         }
 
         function trySubstituteImportedName(node: Identifier): Expression {
-            if ((getNodeEmitFlags(node) & NodeEmitFlags.LocalName) === 0) {
+            if ((getEmitFlags(node) & EmitFlags.LocalName) === 0) {
                 const declaration = resolver.getReferencedImportDeclaration(node);
                 if (declaration) {
                     if (isImportClause(declaration)) {
@@ -1077,7 +1078,7 @@ namespace ts {
                 if (includeNonAmdDependencies && importAliasName) {
                     // Set emitFlags on the name of the classDeclaration
                     // This is so that when printer will not substitute the identifier
-                    setNodeEmitFlags(importAliasName, NodeEmitFlags.NoSubstitution);
+                    setEmitFlags(importAliasName, EmitFlags.NoSubstitution);
                     aliasedModuleNames.push(externalModuleName);
                     importAliasNames.push(createParameter(importAliasName));
                 }
diff --git a/src/compiler/transformers/module/system.ts b/src/compiler/transformers/module/system.ts
index 7b013e18e7d..2a14f341272 100644
--- a/src/compiler/transformers/module/system.ts
+++ b/src/compiler/transformers/module/system.ts
@@ -10,8 +10,6 @@ namespace ts {
         }
 
         const {
-            getNodeEmitFlags,
-            setNodeEmitFlags,
             startLexicalEnvironment,
             endLexicalEnvironment,
             hoistVariableDeclaration,
@@ -50,6 +48,10 @@ namespace ts {
         return transformSourceFile;
 
         function transformSourceFile(node: SourceFile) {
+            if (isDeclarationFile(node)) {
+                return node;
+            }
+
             if (isExternalModule(node) || compilerOptions.isolatedModules) {
                 currentSourceFile = node;
                 currentNode = node;
@@ -116,9 +118,9 @@ namespace ts {
                     createParameter(contextObjectForFile)
                 ],
                 /*type*/ undefined,
-                setNodeEmitFlags(
+                setEmitFlags(
                     createBlock(statements, /*location*/ undefined, /*multiLine*/ true),
-                    NodeEmitFlags.EmitEmitHelpers
+                    EmitFlags.EmitEmitHelpers
                 )
             );
 
@@ -135,7 +137,7 @@ namespace ts {
                             : [dependencies, body]
                     )
                 )
-            ], /*nodeEmitFlags*/ ~NodeEmitFlags.EmitEmitHelpers & getNodeEmitFlags(node));
+            ], /*nodeEmitFlags*/ ~EmitFlags.EmitEmitHelpers & getEmitFlags(node));
         }
 
         /**
@@ -1053,7 +1055,7 @@ namespace ts {
         }
 
         function substituteAssignmentExpression(node: BinaryExpression): Expression {
-            setNodeEmitFlags(node, NodeEmitFlags.NoSubstitution);
+            setEmitFlags(node, EmitFlags.NoSubstitution);
 
             const left = node.left;
             switch (left.kind) {
@@ -1176,7 +1178,7 @@ namespace ts {
                 const exportDeclaration = resolver.getReferencedExportContainer(<Identifier>operand);
                 if (exportDeclaration) {
                     const expr = createPrefix(node.operator, operand, node);
-                    setNodeEmitFlags(expr, NodeEmitFlags.NoSubstitution);
+                    setEmitFlags(expr, EmitFlags.NoSubstitution);
                     const call = createExportExpression(<Identifier>operand, expr);
                     if (node.kind === SyntaxKind.PrefixUnaryExpression) {
                         return call;
@@ -1241,7 +1243,7 @@ namespace ts {
                             ]),
                             m,
                             createBlock([
-                                setNodeEmitFlags(
+                                setEmitFlags(
                                     createIf(
                                         condition,
                                         createStatement(
@@ -1251,7 +1253,7 @@ namespace ts {
                                             )
                                         )
                                     ),
-                                    NodeEmitFlags.SingleLine
+                                    EmitFlags.SingleLine
                                 )
                             ])
                         ),
@@ -1393,10 +1395,10 @@ namespace ts {
             hoistBindingElement(node, /*isExported*/ false);
         }
 
-        function updateSourceFile(node: SourceFile, statements: Statement[], nodeEmitFlags: NodeEmitFlags) {
+        function updateSourceFile(node: SourceFile, statements: Statement[], nodeEmitFlags: EmitFlags) {
             const updated = getMutableClone(node);
             updated.statements = createNodeArray(statements, node.statements);
-            setNodeEmitFlags(updated, nodeEmitFlags);
+            setEmitFlags(updated, nodeEmitFlags);
             return updated;
         }
     }
diff --git a/src/compiler/transformers/ts.ts b/src/compiler/transformers/ts.ts
index d41a32d92c7..e1892ff5bf4 100644
--- a/src/compiler/transformers/ts.ts
+++ b/src/compiler/transformers/ts.ts
@@ -24,10 +24,6 @@ namespace ts {
 
     export function transformTypeScript(context: TransformationContext) {
         const {
-            getNodeEmitFlags,
-            setNodeEmitFlags,
-            setCommentRange,
-            setSourceMapRange,
             startLexicalEnvironment,
             endLexicalEnvironment,
             hoistVariableDeclaration,
@@ -85,6 +81,10 @@ namespace ts {
          * @param node A SourceFile node.
          */
         function transformSourceFile(node: SourceFile) {
+            if (isDeclarationFile(node)) {
+                return node;
+            }
+
             return visitNode(node, visitor, isSourceFile);
         }
 
@@ -449,7 +449,7 @@ namespace ts {
                 node = visitEachChild(node, visitor, context);
             }
 
-            setNodeEmitFlags(node, NodeEmitFlags.EmitEmitHelpers | node.emitFlags);
+            setEmitFlags(node, EmitFlags.EmitEmitHelpers | getEmitFlags(node));
             return node;
         }
 
@@ -521,7 +521,7 @@ namespace ts {
                 // To better align with the old emitter, we should not emit a trailing source map
                 // entry if the class has static properties.
                 if (staticProperties.length > 0) {
-                    setNodeEmitFlags(classDeclaration, NodeEmitFlags.NoTrailingSourceMap | getNodeEmitFlags(classDeclaration));
+                    setEmitFlags(classDeclaration, EmitFlags.NoTrailingSourceMap | getEmitFlags(classDeclaration));
                 }
 
                 statements.push(classDeclaration);
@@ -776,7 +776,7 @@ namespace ts {
 
                 // To preserve the behavior of the old emitter, we explicitly indent
                 // the body of a class with static initializers.
-                setNodeEmitFlags(classExpression, NodeEmitFlags.Indented | getNodeEmitFlags(classExpression));
+                setEmitFlags(classExpression, EmitFlags.Indented | getEmitFlags(classExpression));
                 expressions.push(startOnNewLine(createAssignment(temp, classExpression)));
                 addRange(expressions, generateInitializedPropertyExpressions(node, staticProperties, temp));
                 expressions.push(startOnNewLine(temp));
@@ -1009,10 +1009,10 @@ namespace ts {
             Debug.assert(isIdentifier(node.name));
             const name = node.name as Identifier;
             const propertyName = getMutableClone(name);
-            setNodeEmitFlags(propertyName, NodeEmitFlags.NoComments | NodeEmitFlags.NoSourceMap);
+            setEmitFlags(propertyName, EmitFlags.NoComments | EmitFlags.NoSourceMap);
 
             const localName = getMutableClone(name);
-            setNodeEmitFlags(localName, NodeEmitFlags.NoComments);
+            setEmitFlags(localName, EmitFlags.NoComments);
 
             return startOnNewLine(
                 createStatement(
@@ -1418,7 +1418,7 @@ namespace ts {
                 moveRangePastDecorators(member)
             );
 
-            setNodeEmitFlags(helper, NodeEmitFlags.NoComments);
+            setEmitFlags(helper, EmitFlags.NoComments);
             return helper;
         }
 
@@ -1467,7 +1467,7 @@ namespace ts {
                 );
 
                 const result = createAssignment(getDeclarationName(node), expression, moveRangePastDecorators(node));
-                setNodeEmitFlags(result, NodeEmitFlags.NoComments);
+                setEmitFlags(result, EmitFlags.NoComments);
                 return result;
             }
             // Emit the call to __decorate. Given the class:
@@ -1491,7 +1491,7 @@ namespace ts {
                     moveRangePastDecorators(node)
                 );
 
-                setNodeEmitFlags(result, NodeEmitFlags.NoComments);
+                setEmitFlags(result, EmitFlags.NoComments);
                 return result;
             }
         }
@@ -1521,7 +1521,7 @@ namespace ts {
                         transformDecorator(decorator),
                         parameterOffset,
                         /*location*/ decorator.expression);
-                    setNodeEmitFlags(helper, NodeEmitFlags.NoComments);
+                    setEmitFlags(helper, EmitFlags.NoComments);
                     expressions.push(helper);
                 }
             }
@@ -2324,11 +2324,11 @@ namespace ts {
                 if (languageVersion >= ScriptTarget.ES6) {
                     if (resolver.getNodeCheckFlags(node) & NodeCheckFlags.AsyncMethodWithSuperBinding) {
                         enableSubstitutionForAsyncMethodsWithSuper();
-                        setNodeEmitFlags(block, NodeEmitFlags.EmitAdvancedSuperHelper);
+                        setEmitFlags(block, EmitFlags.EmitAdvancedSuperHelper);
                     }
                     else if (resolver.getNodeCheckFlags(node) & NodeCheckFlags.AsyncMethodWithSuper) {
                         enableSubstitutionForAsyncMethodsWithSuper();
-                        setNodeEmitFlags(block, NodeEmitFlags.EmitSuperHelper);
+                        setEmitFlags(block, EmitFlags.EmitSuperHelper);
                     }
                 }
 
@@ -2375,7 +2375,7 @@ namespace ts {
             setOriginalNode(parameter, node);
             setCommentRange(parameter, node);
             setSourceMapRange(parameter, moveRangePastModifiers(node));
-            setNodeEmitFlags(parameter.name, NodeEmitFlags.NoTrailingSourceMap);
+            setEmitFlags(parameter.name, EmitFlags.NoTrailingSourceMap);
 
             return parameter;
         }
@@ -2534,7 +2534,7 @@ namespace ts {
 
             // We request to be advised when the printer is about to print this node. This allows
             // us to set up the correct state for later substitutions.
-            let emitFlags = NodeEmitFlags.AdviseOnEmitNode;
+            let emitFlags = EmitFlags.AdviseOnEmitNode;
 
             // If needed, we should emit a variable declaration for the enum. If we emit
             // a leading variable declaration, we should not emit leading comments for the
@@ -2544,7 +2544,7 @@ namespace ts {
 
                 // We should still emit the comments if we are emitting a system module.
                 if (moduleKind !== ModuleKind.System || currentScope !== currentSourceFile) {
-                    emitFlags |= NodeEmitFlags.NoLeadingComments;
+                    emitFlags |= EmitFlags.NoLeadingComments;
                 }
             }
 
@@ -2584,7 +2584,7 @@ namespace ts {
             );
 
             setOriginalNode(enumStatement, node);
-            setNodeEmitFlags(enumStatement, emitFlags);
+            setEmitFlags(enumStatement, emitFlags);
             statements.push(enumStatement);
 
             if (isNamespaceExport(node)) {
@@ -2736,7 +2736,7 @@ namespace ts {
             //     })(m1 || (m1 = {})); // trailing comment module
             //
             setCommentRange(statement, node);
-            setNodeEmitFlags(statement, NodeEmitFlags.NoTrailingComments);
+            setEmitFlags(statement, EmitFlags.NoTrailingComments);
             statements.push(statement);
         }
 
@@ -2759,7 +2759,7 @@ namespace ts {
 
             // We request to be advised when the printer is about to print this node. This allows
             // us to set up the correct state for later substitutions.
-            let emitFlags = NodeEmitFlags.AdviseOnEmitNode;
+            let emitFlags = EmitFlags.AdviseOnEmitNode;
 
             // If needed, we should emit a variable declaration for the module. If we emit
             // a leading variable declaration, we should not emit leading comments for the
@@ -2768,7 +2768,7 @@ namespace ts {
                 addVarForEnumOrModuleDeclaration(statements, node);
                 // We should still emit the comments if we are emitting a system module.
                 if (moduleKind !== ModuleKind.System || currentScope !== currentSourceFile) {
-                    emitFlags |= NodeEmitFlags.NoLeadingComments;
+                    emitFlags |= EmitFlags.NoLeadingComments;
                 }
             }
 
@@ -2820,7 +2820,7 @@ namespace ts {
             );
 
             setOriginalNode(moduleStatement, node);
-            setNodeEmitFlags(moduleStatement, emitFlags);
+            setEmitFlags(moduleStatement, emitFlags);
             statements.push(moduleStatement);
             return statements;
         }
@@ -2895,7 +2895,7 @@ namespace ts {
             // })(hello || (hello = {}));
             // We only want to emit comment on the namespace which contains block body itself, not the containing namespaces.
             if (body.kind !== SyntaxKind.ModuleBlock) {
-                setNodeEmitFlags(block, block.emitFlags | NodeEmitFlags.NoComments);
+                setEmitFlags(block, getEmitFlags(block) | EmitFlags.NoComments);
             }
             return block;
         }
@@ -2936,7 +2936,7 @@ namespace ts {
             }
 
             const moduleReference = createExpressionFromEntityName(<EntityName>node.moduleReference);
-            setNodeEmitFlags(moduleReference, NodeEmitFlags.NoComments | NodeEmitFlags.NoNestedComments);
+            setEmitFlags(moduleReference, EmitFlags.NoComments | EmitFlags.NoNestedComments);
 
             if (isNamedExternalModuleExport(node) || !isNamespaceExport(node)) {
                 //  export var ${name} = ${moduleReference};
@@ -3048,15 +3048,15 @@ namespace ts {
 
         function getNamespaceMemberName(name: Identifier, allowComments?: boolean, allowSourceMaps?: boolean): Expression {
             const qualifiedName = createPropertyAccess(currentNamespaceContainerName, getSynthesizedClone(name), /*location*/ name);
-            let emitFlags: NodeEmitFlags;
+            let emitFlags: EmitFlags;
             if (!allowComments) {
-                emitFlags |= NodeEmitFlags.NoComments;
+                emitFlags |= EmitFlags.NoComments;
             }
             if (!allowSourceMaps) {
-                emitFlags |= NodeEmitFlags.NoSourceMap;
+                emitFlags |= EmitFlags.NoSourceMap;
             }
             if (emitFlags) {
-                setNodeEmitFlags(qualifiedName, emitFlags);
+                setEmitFlags(qualifiedName, emitFlags);
             }
             return qualifiedName;
         }
@@ -3093,7 +3093,7 @@ namespace ts {
          * @param allowComments A value indicating whether comments may be emitted for the name.
          */
         function getLocalName(node: DeclarationStatement | ClassExpression, noSourceMaps?: boolean, allowComments?: boolean) {
-            return getDeclarationName(node, allowComments, !noSourceMaps, NodeEmitFlags.LocalName);
+            return getDeclarationName(node, allowComments, !noSourceMaps, EmitFlags.LocalName);
         }
 
         /**
@@ -3111,7 +3111,7 @@ namespace ts {
                 return getNamespaceMemberName(getDeclarationName(node), allowComments, !noSourceMaps);
             }
 
-            return getDeclarationName(node, allowComments, !noSourceMaps, NodeEmitFlags.ExportName);
+            return getDeclarationName(node, allowComments, !noSourceMaps, EmitFlags.ExportName);
         }
 
         /**
@@ -3122,20 +3122,20 @@ namespace ts {
          * @param allowSourceMaps A value indicating whether source maps may be emitted for the name.
          * @param emitFlags Additional NodeEmitFlags to specify for the name.
          */
-        function getDeclarationName(node: DeclarationStatement | ClassExpression, allowComments?: boolean, allowSourceMaps?: boolean, emitFlags?: NodeEmitFlags) {
+        function getDeclarationName(node: DeclarationStatement | ClassExpression, allowComments?: boolean, allowSourceMaps?: boolean, emitFlags?: EmitFlags) {
             if (node.name) {
                 const name = getMutableClone(node.name);
-                emitFlags |= getNodeEmitFlags(node.name);
+                emitFlags |= getEmitFlags(node.name);
                 if (!allowSourceMaps) {
-                    emitFlags |= NodeEmitFlags.NoSourceMap;
+                    emitFlags |= EmitFlags.NoSourceMap;
                 }
 
                 if (!allowComments) {
-                    emitFlags |= NodeEmitFlags.NoComments;
+                    emitFlags |= EmitFlags.NoComments;
                 }
 
                 if (emitFlags) {
-                    setNodeEmitFlags(name, emitFlags);
+                    setEmitFlags(name, emitFlags);
                 }
 
                 return name;
@@ -3342,7 +3342,7 @@ namespace ts {
 
         function trySubstituteNamespaceExportedName(node: Identifier): Expression {
             // If this is explicitly a local name, do not substitute.
-            if (enabledSubstitutions & applicableSubstitutions && (getNodeEmitFlags(node) & NodeEmitFlags.LocalName) === 0) {
+            if (enabledSubstitutions & applicableSubstitutions && (getEmitFlags(node) & EmitFlags.LocalName) === 0) {
                 // If we are nested within a namespace declaration, we may need to qualifiy
                 // an identifier that is exported from a merged namespace.
                 const container = resolver.getReferencedExportContainer(node, /*prefixLocals*/ false);
diff --git a/src/compiler/types.ts b/src/compiler/types.ts
index b1b672d015b..c18ebdd7200 100644
--- a/src/compiler/types.ts
+++ b/src/compiler/types.ts
@@ -493,10 +493,7 @@ namespace ts {
         /* @internal */ nextContainer?: Node;           // Next container in declaration order (initialized by binding)
         /* @internal */ localSymbol?: Symbol;           // Local symbol declared by node (initialized by binding only for exported nodes)
         /* @internal */ flowNode?: FlowNode;            // Associated FlowNode (initialized by binding)
-        /* @internal */ transformId?: number;           // Associates transient transformation properties with a specific transformation (initialized by transformation).
-        /* @internal */ emitFlags?: NodeEmitFlags;      // Transient emit flags for a synthesized node (initialized by transformation).
-        /* @internal */ sourceMapRange?: TextRange;     // Transient custom sourcemap range for a synthesized node (initialized by transformation).
-        /* @internal */ commentRange?: TextRange;       // Transient custom comment range for a synthesized node (initialized by transformation).
+        /* @internal */ emitNode?: EmitNode;            // Associated EmitNode (initialized by transforms)
     }
 
     export interface NodeArray<T extends Node> extends Array<T>, TextRange {
@@ -3153,7 +3150,16 @@ namespace ts {
     }
 
     /* @internal */
-    export const enum NodeEmitFlags {
+    export interface EmitNode {
+        flags?: EmitFlags;
+        commentRange?: TextRange;
+        sourceMapRange?: TextRange;
+        tokenSourceMapRanges?: Map<TextRange>;
+        annotatedNodes?: Node[];                // Tracks Parse-tree nodes with EmitNodes for eventual cleanup.
+    }
+
+    /* @internal */
+    export const enum EmitFlags {
         EmitEmitHelpers = 1 << 0,                // Any emit helpers should be written to this node.
         EmitExportStar = 1 << 1,                 // The export * helper should be written to this node.
         EmitSuperHelper = 1 << 2,                // Emit the basic _super helper for async methods.

From c1ee53497465bcd3a6f5915c5fb97f475e6dc861 Mon Sep 17 00:00:00 2001
From: Ron Buckton <rbuckton@microsoft.com>
Date: Mon, 26 Sep 2016 13:52:09 -0700
Subject: [PATCH 33/47] Clean up SourceMapWriter and emitter.

---
 src/compiler/emitter.ts     | 137 +--------
 src/compiler/sourcemap.ts   | 545 ++++++------------------------------
 src/compiler/transformer.ts |  73 ++---
 3 files changed, 141 insertions(+), 614 deletions(-)

diff --git a/src/compiler/emitter.ts b/src/compiler/emitter.ts
index 5487057bbca..8457ea41d02 100644
--- a/src/compiler/emitter.ts
+++ b/src/compiler/emitter.ts
@@ -203,10 +203,8 @@ const _super = (function (geti, seti) {
 
         const sourceMap = createSourceMapWriter(host, writer);
         const {
-            emitStart,
-            emitEnd,
-            emitTokenStart,
-            emitTokenEnd
+            emitNodeWithSourceMap,
+            emitTokenWithSourceMap
         } = sourceMap;
 
         const comments = createCommentWriter(host, writer, sourceMap);
@@ -244,10 +242,8 @@ const _super = (function (geti, seti) {
 
         // Extract helpers from the result
         const {
-            isSubstitutionEnabled,
-            isEmitNotificationEnabled,
-            onSubstituteNode,
-            onEmitNode
+            emitNodeWithSubstitution,
+            emitNodeWithNotification
         } = transformed;
 
         performance.mark("beforePrint");
@@ -448,101 +444,6 @@ const _super = (function (geti, seti) {
             emitNodeWithSubstitution(node, /*isExpression*/ true, emitExpressionWorker);
         }
 
-        /**
-         * Emits a node with possible emit notification.
-         */
-        // TODO(rbuckton): Move this into transformer.ts
-        function emitNodeWithNotification(node: Node, emitCallback: (node: Node) => void) {
-            if (node) {
-                if (isEmitNotificationEnabled(node)) {
-                    onEmitNode(node, emitCallback);
-                }
-                else {
-                    emitCallback(node);
-                }
-            }
-        }
-
-        /**
-         * Emits a node with possible source maps.
-         */
-        // TODO(rbuckton): Move this into sourcemap.ts
-        function emitNodeWithSourceMap(node: Node, emitCallback: (node: Node) => void) {
-            if (node) {
-                emitStart(/*range*/ node, /*contextNode*/ node, shouldSkipLeadingSourceMapForNode, shouldSkipSourceMapForChildren, getSourceMapRange);
-                emitCallback(node);
-                emitEnd(/*range*/ node, /*contextNode*/ node, shouldSkipTrailingSourceMapForNode, shouldSkipSourceMapForChildren, getSourceMapRange);
-            }
-        }
-
-        /**
-         * Determines whether to skip leading comment emit for a node.
-         *
-         * We do not emit comments for NotEmittedStatement nodes or any node that has
-         * NodeEmitFlags.NoLeadingComments.
-         *
-         * @param node A Node.
-         */
-        // TODO(rbuckton): Move this into comments.ts
-        function shouldSkipLeadingCommentsForNode(node: Node) {
-            return isNotEmittedStatement(node)
-                || (getEmitFlags(node) & EmitFlags.NoLeadingComments) !== 0;
-        }
-
-        /**
-         * Determines whether to skip source map emit for the start position of a node.
-         *
-         * We do not emit source maps for NotEmittedStatement nodes or any node that
-         * has NodeEmitFlags.NoLeadingSourceMap.
-         *
-         * @param node A Node.
-         */
-        // TODO(rbuckton): Move this into sourcemap.ts
-        function shouldSkipLeadingSourceMapForNode(node: Node) {
-            return isNotEmittedStatement(node)
-                || (getEmitFlags(node) & EmitFlags.NoLeadingSourceMap) !== 0;
-        }
-
-        /**
-         * Determines whether to skip source map emit for the end position of a node.
-         *
-         * We do not emit source maps for NotEmittedStatement nodes or any node that
-         * has NodeEmitFlags.NoTrailingSourceMap.
-         *
-         * @param node A Node.
-         */
-        // TODO(rbuckton): Move this into sourcemap.ts
-        function shouldSkipTrailingSourceMapForNode(node: Node) {
-            return isNotEmittedStatement(node)
-                || (getEmitFlags(node) & EmitFlags.NoTrailingSourceMap) !== 0;
-        }
-
-        /**
-         * Determines whether to skip source map emit for a node and its children.
-         *
-         * We do not emit source maps for a node that has NodeEmitFlags.NoNestedSourceMaps.
-         */
-        // TODO(rbuckton): Move this into sourcemap.ts
-        function shouldSkipSourceMapForChildren(node: Node) {
-            return (getEmitFlags(node) & EmitFlags.NoNestedSourceMaps) !== 0;
-        }
-
-        /**
-         * Emits a node with possible substitution.
-         */
-        // TODO(rbuckton): Move this into transformer.ts
-        function emitNodeWithSubstitution(node: Node, isExpression: boolean, emitCallback: (node: Node) => void) {
-            if (isSubstitutionEnabled(node) && (getEmitFlags(node) & EmitFlags.NoSubstitution) === 0) {
-                const substitute = onSubstituteNode(node, isExpression);
-                if (substitute !== node) {
-                    emitCallback(substitute);
-                    return;
-                }
-            }
-
-            emitCallback(node);
-        }
-
         /**
          * Emits a node.
          *
@@ -585,7 +486,7 @@ const _super = (function (geti, seti) {
                 case SyntaxKind.StringKeyword:
                 case SyntaxKind.SymbolKeyword:
                 case SyntaxKind.GlobalKeyword:
-                    return writeTokenNode(node);
+                    return emitTokenNode(node);
 
                 // Parse tree nodes
 
@@ -832,7 +733,7 @@ const _super = (function (geti, seti) {
                 case SyntaxKind.SuperKeyword:
                 case SyntaxKind.TrueKeyword:
                 case SyntaxKind.ThisKeyword:
-                    return writeTokenNode(node);
+                    return emitTokenNode(node);
 
                 // Expressions
                 case SyntaxKind.ArrayLiteralExpression:
@@ -2129,7 +2030,7 @@ const _super = (function (geti, seti) {
             // "comment1" is not considered to be leading comment for node.initializer
             // but rather a trailing comment on the previous node.
             const initializer = node.initializer;
-            if (!shouldSkipLeadingCommentsForNode(initializer)) {
+            if ((getEmitFlags(initializer) & EmitFlags.NoLeadingComments) === 0) {
                 const commentRange = getCommentRange(initializer);
                 emitTrailingCommentsOfPosition(commentRange.pos);
             }
@@ -2537,17 +2438,7 @@ const _super = (function (geti, seti) {
         }
 
         function writeToken(token: SyntaxKind, pos: number, contextNode?: Node) {
-            const tokenStartPos = emitTokenStart(token, pos, contextNode, shouldSkipLeadingSourceMapForToken, getTokenSourceMapRange);
-            const tokenEndPos = writeTokenText(token, tokenStartPos);
-            return emitTokenEnd(token, tokenEndPos, contextNode, shouldSkipTrailingSourceMapForToken, getTokenSourceMapRange);
-        }
-
-        function shouldSkipLeadingSourceMapForToken(contextNode: Node) {
-            return (getEmitFlags(contextNode) & EmitFlags.NoTokenLeadingSourceMaps) !== 0;
-        }
-
-        function shouldSkipTrailingSourceMapForToken(contextNode: Node) {
-            return (getEmitFlags(contextNode) & EmitFlags.NoTokenTrailingSourceMaps) !== 0;
+            return emitTokenWithSourceMap(contextNode, token, pos, writeTokenText);
         }
 
         function writeTokenText(token: SyntaxKind, pos?: number) {
@@ -2556,12 +2447,12 @@ const _super = (function (geti, seti) {
             return positionIsSynthesized(pos) ? -1 : pos + tokenString.length;
         }
 
-        function writeTokenNode(node: Node) {
-            if (node) {
-                emitStart(/*range*/ node, /*contextNode*/ node, shouldSkipLeadingSourceMapForNode, shouldSkipSourceMapForChildren, getSourceMapRange);
-                writeTokenText(node.kind);
-                emitEnd(/*range*/ node, /*contextNode*/ node, shouldSkipTrailingSourceMapForNode, shouldSkipSourceMapForChildren, getSourceMapRange);
-            }
+        function emitTokenNode(node: Node) {
+            emitNodeWithSourceMap(node, emitTokenNodeWorker);
+        }
+
+        function emitTokenNodeWorker(node: Node) {
+            writeTokenText(node.kind);
         }
 
         function increaseIndentIf(value: boolean, valueToWriteWhenNotIndenting?: string) {
diff --git a/src/compiler/sourcemap.ts b/src/compiler/sourcemap.ts
index eb369be39d7..3517c54b407 100644
--- a/src/compiler/sourcemap.ts
+++ b/src/compiler/sourcemap.ts
@@ -18,11 +18,6 @@ namespace ts {
          */
         reset(): void;
 
-        /**
-         * Gets test data for source maps.
-         */
-        getSourceMapData(): SourceMapData;
-
         /**
          * Set the current source file.
          *
@@ -41,123 +36,22 @@ namespace ts {
         emitPos(pos: number): void;
 
         /**
-         * Emits a mapping for the start of a range.
+         * Emits a node with possible leading and trailing source maps.
          *
-         * If the range's start position is synthetic (undefined or a negative value), no mapping
-         * will be created. Any trivia at the start position in the original source will be
-         * skipped.
-         *
-         * @param range The range to emit.
+         * @param node The node to emit.
+         * @param emitCallback The callback used to emit the node.
          */
-        emitStart(range: TextRange): void;
+        emitNodeWithSourceMap(node: Node, emitCallback: (node: Node) => void): void;
 
         /**
-         * Emits a mapping for the start of a range.
-         *
-         * If the node's start position is synthetic (undefined or a negative value), no mapping
-         * will be created. Any trivia at the start position in the original source will be
-         * skipped.
-         *
-         * @param range The range to emit.
-         * @param contextNode The node for the current range.
-         * @param ignoreNodeCallback A callback used to determine whether to skip source map
-         *        emit for the start position of this node.
-         * @param ignoreChildrenCallback A callback used to determine whether to skip source
-         *        map emit for all children of this node.
-         * @param getTextRangeCallbackCallback A callback used to get a custom source map
-         *        range for this node.
-         */
-        emitStart(range: TextRange, contextNode: Node, ignoreNodeCallback: (node: Node) => boolean, ignoreChildrenCallback: (node: Node) => boolean, getTextRangeCallbackCallback: (node: Node) => TextRange): void;
-
-        /**
-         * Emits a mapping for the end of a range.
-         *
-         * If the range's end position is synthetic (undefined or a negative value), no mapping
-         * will be created.
-         *
-         * @param range The range to emit.
-         */
-        emitEnd(range: TextRange): void;
-
-        /**
-         * Emits a mapping for the end of a range.
-         *
-         * If the node's end position is synthetic (undefined or a negative value), no mapping
-         * will be created.
-         *
-         * @param range The range to emit.
-         * @param contextNode The node for the current range.
-         * @param ignoreNodeCallback A callback used to determine whether to skip source map
-         *        emit for the end position of this node.
-         * @param ignoreChildrenCallback A callback used to determine whether to skip source
-         *        map emit for all children of this node.
-         * @param getTextRangeCallbackCallback A callback used to get a custom source map
-         *        range for this node.
-         */
-        emitEnd(range: TextRange, contextNode: Node, ignoreNodeCallback: (node: Node) => boolean, ignoreChildrenCallback: (node: Node) => boolean, getTextRangeCallbackCallback: (node: Node) => TextRange): void;
-
-        /**
-         * Emits a mapping for the start position of a token.
-         *
-         * If the token's start position is synthetic (undefined or a negative value), no mapping
-         * will be created. Any trivia at the start position in the original source will be
-         * skipped.
+         * Emits a token of a node node with possible leading and trailing source maps.
          *
+         * @param node The node containing the token.
          * @param token The token to emit.
-         * @param tokenStartPos The start position of the token.
-         * @returns The start position of the token, following any trivia.
+         * @param tokenStartPos The start pos of the token.
+         * @param emitCallback The callback used to emit the token.
          */
-        emitTokenStart(token: SyntaxKind, tokenStartPos: number): number;
-
-        /**
-         * Emits a mapping for the start position of a token.
-         *
-         * If the token's start position is synthetic (undefined or a negative value), no mapping
-         * will be created. Any trivia at the start position in the original source will be
-         * skipped.
-         *
-         * @param token The token to emit.
-         * @param tokenStartPos The start position of the token.
-         * @param contextNode The node containing this token.
-         * @param ignoreTokenCallback A callback used to determine whether to skip source map
-         *        emit for the start position of this token.
-         * @param getTokenTextRangeCallback A callback used to get a custom source
-         *        map range for this node.
-         * @returns The start position of the token, following any trivia.
-         */
-        emitTokenStart(token: SyntaxKind, tokenStartPos: number, contextNode: Node, ignoreTokenCallback: (node: Node, token: SyntaxKind) => boolean, getTokenTextRangeCallback: (node: Node, token: SyntaxKind) => TextRange): number;
-
-        /**
-         * Emits a mapping for the end position of a token.
-         *
-         * If the token's end position is synthetic (undefined or a negative value), no mapping
-         * will be created.
-         *
-         * @param token The token to emit.
-         * @param tokenEndPos The end position of the token.
-         * @returns The end position of the token.
-         */
-        emitTokenEnd(token: SyntaxKind, tokenEndPos: number): number;
-
-        /**
-         * Emits a mapping for the end position of a token.
-         *
-         * If the token's end position is synthetic (undefined or a negative value), no mapping
-         * will be created.
-         *
-         * @param token The token to emit.
-         * @param tokenEndPos The end position of the token.
-         * @param contextNode The node containing this token.
-         * @param ignoreTokenCallback A callback used to determine whether to skip source map
-         *        emit for the end position of this token.
-         * @param getTokenTextRangeCallback A callback used to get a custom source
-         *        map range for this node.
-         * @returns The end position of the token.
-         */
-        emitTokenEnd(token: SyntaxKind, tokenEndPos: number, contextNode: Node, ignoreTokenCallback: (node: Node, token: SyntaxKind) => boolean, getTokenTextRangeCallback: (node: Node, token: SyntaxKind) => TextRange): number;
-
-        /*@deprecated*/ changeEmitSourcePos(): void;
-        /*@deprecated*/ stopOverridingSpan(): void;
+        emitTokenWithSourceMap(node: Node, token: SyntaxKind, tokenStartPos: number, emitCallback: (token: SyntaxKind, tokenStartPos: number) => number): number;
 
         /**
          * Gets the text for the source map.
@@ -168,44 +62,11 @@ namespace ts {
          * Gets the SourceMappingURL for the source map.
          */
         getSourceMappingURL(): string;
-    }
 
-    export function createSourceMapWriter(host: EmitHost, writer: EmitTextWriter): SourceMapWriter {
-        const compilerOptions = host.getCompilerOptions();
-        if (compilerOptions.sourceMap || compilerOptions.inlineSourceMap) {
-            if (compilerOptions.extendedDiagnostics) {
-                return createSourceMapWriterWithExtendedDiagnostics(host, writer);
-            }
-
-            return createSourceMapWriterWorker(host, writer);
-        }
-        else {
-            return getNullSourceMapWriter();
-        }
-    }
-
-    let nullSourceMapWriter: SourceMapWriter;
-
-    export function getNullSourceMapWriter(): SourceMapWriter {
-        if (nullSourceMapWriter === undefined) {
-            nullSourceMapWriter = {
-                initialize(filePath: string, sourceMapFilePath: string, sourceFiles: SourceFile[], isBundledEmit: boolean): void { },
-                reset(): void { },
-                getSourceMapData(): SourceMapData { return undefined; },
-                setSourceFile(sourceFile: SourceFile): void { },
-                emitPos(pos: number): void { },
-                emitStart(range: TextRange, contextNode?: Node, ignoreNodeCallback?: (node: Node) => boolean, ignoreChildrenCallback?: (node: Node) => boolean, getTextRangeCallback?: (node: Node) => TextRange): void { },
-                emitEnd(range: TextRange, contextNode?: Node, ignoreNodeCallback?: (node: Node) => boolean, ignoreChildrenCallback?: (node: Node) => boolean, getTextRangeCallback?: (node: Node) => TextRange): void { },
-                emitTokenStart(token: SyntaxKind, pos: number, contextNode?: Node, ignoreTokenCallback?: (node: Node) => boolean, getTokenTextRangeCallback?: (node: Node, token: SyntaxKind) => TextRange): number { return -1; },
-                emitTokenEnd(token: SyntaxKind, end: number, contextNode?: Node, ignoreTokenCallback?: (node: Node) => boolean, getTokenTextRangeCallback?: (node: Node, token: SyntaxKind) => TextRange): number { return -1; },
-                changeEmitSourcePos(): void { },
-                stopOverridingSpan(): void { },
-                getText(): string { return undefined; },
-                getSourceMappingURL(): string { return undefined; }
-            };
-        }
-
-        return nullSourceMapWriter;
+        /**
+         * Gets test data for source maps.
+         */
+        getSourceMapData(): SourceMapData;
     }
 
     // Used for initialize lastEncodedSourceMapSpan and reset lastEncodedSourceMapSpan when updateLastEncodedAndRecordedSpans
@@ -217,14 +78,12 @@ namespace ts {
         sourceIndex: 0
     };
 
-    function createSourceMapWriterWorker(host: EmitHost, writer: EmitTextWriter): SourceMapWriter {
+    export function createSourceMapWriter(host: EmitHost, writer: EmitTextWriter): SourceMapWriter {
         const compilerOptions = host.getCompilerOptions();
         const extendedDiagnostics = compilerOptions.extendedDiagnostics;
         let currentSourceFile: SourceFile;
         let currentSourceText: string;
         let sourceMapDir: string; // The directory in which sourcemap will be
-        let stopOverridingSpan = false;
-        let modifyLastSourcePos = false;
 
         // Current source map file and its index in the sources list
         let sourceMapSourceIndex: number;
@@ -236,13 +95,7 @@ namespace ts {
 
         // Source map data
         let sourceMapData: SourceMapData;
-
-        // This keeps track of the number of times `disable` has been called without a
-        // corresponding call to `enable`. As long as this value is non-zero, mappings will not
-        // be recorded.
-        // This is primarily used to provide a better experience when debugging binding
-        // patterns and destructuring assignments for simple expressions.
-        let disableDepth: number;
+        let disabled: boolean = !(compilerOptions.sourceMap || compilerOptions.inlineSourceMap);
 
         return {
             initialize,
@@ -250,12 +103,8 @@ namespace ts {
             getSourceMapData: () => sourceMapData,
             setSourceFile,
             emitPos,
-            emitStart,
-            emitEnd,
-            emitTokenStart,
-            emitTokenEnd,
-            changeEmitSourcePos,
-            stopOverridingSpan: () => stopOverridingSpan = true,
+            emitNodeWithSourceMap,
+            emitTokenWithSourceMap,
             getText,
             getSourceMappingURL,
         };
@@ -269,13 +118,16 @@ namespace ts {
          * @param isBundledEmit A value indicating whether the generated output file is a bundle.
          */
         function initialize(filePath: string, sourceMapFilePath: string, sourceFiles: SourceFile[], isBundledEmit: boolean) {
+            if (disabled) {
+                return;
+            }
+
             if (sourceMapData) {
                 reset();
             }
 
             currentSourceFile = undefined;
             currentSourceText = undefined;
-            disableDepth = 0;
 
             // Current source map file and its index in the sources list
             sourceMapSourceIndex = -1;
@@ -338,6 +190,10 @@ namespace ts {
          * Reset the SourceMapWriter to an empty state.
          */
         function reset() {
+            if (disabled) {
+                return;
+            }
+
             currentSourceFile = undefined;
             sourceMapDir = undefined;
             sourceMapSourceIndex = undefined;
@@ -345,64 +201,6 @@ namespace ts {
             lastEncodedSourceMapSpan = undefined;
             lastEncodedNameIndex = undefined;
             sourceMapData = undefined;
-            disableDepth = 0;
-        }
-
-        /**
-         * Re-enables the recording of mappings.
-         */
-        function enable() {
-            if (disableDepth > 0) {
-                disableDepth--;
-            }
-        }
-
-        /**
-         * Disables the recording of mappings.
-         */
-        function disable() {
-            disableDepth++;
-        }
-
-        function updateLastEncodedAndRecordedSpans() {
-            if (modifyLastSourcePos) {
-                // Reset the source pos
-                modifyLastSourcePos = false;
-
-                // Change Last recorded Map with last encoded emit line and character
-                lastRecordedSourceMapSpan.emittedLine = lastEncodedSourceMapSpan.emittedLine;
-                lastRecordedSourceMapSpan.emittedColumn = lastEncodedSourceMapSpan.emittedColumn;
-
-                // Pop sourceMapDecodedMappings to remove last entry
-                sourceMapData.sourceMapDecodedMappings.pop();
-
-                // Point the lastEncodedSourceMapSpace to the previous encoded sourceMapSpan
-                // If the list is empty which indicates that we are at the beginning of the file,
-                // we have to reset it to default value (same value when we first initialize sourceMapWriter)
-                lastEncodedSourceMapSpan = sourceMapData.sourceMapDecodedMappings.length ?
-                    sourceMapData.sourceMapDecodedMappings[sourceMapData.sourceMapDecodedMappings.length - 1] :
-                    defaultLastEncodedSourceMapSpan;
-
-                // TODO: Update lastEncodedNameIndex
-                // Since we dont support this any more, lets not worry about it right now.
-                // When we start supporting nameIndex, we will get back to this
-
-                // Change the encoded source map
-                const sourceMapMappings = sourceMapData.sourceMapMappings;
-                let lenthToSet = sourceMapMappings.length - 1;
-                for (; lenthToSet >= 0; lenthToSet--) {
-                    const currentChar = sourceMapMappings.charAt(lenthToSet);
-                    if (currentChar === ",") {
-                        // Separator for the entry found
-                        break;
-                    }
-                    if (currentChar === ";" && lenthToSet !== 0 && sourceMapMappings.charAt(lenthToSet - 1) !== ";") {
-                        // Last line separator found
-                        break;
-                    }
-                }
-                sourceMapData.sourceMapMappings = sourceMapMappings.substr(0, Math.max(0, lenthToSet));
-            }
         }
 
         // Encoding for sourcemap span
@@ -459,7 +257,7 @@ namespace ts {
          * @param pos The position.
          */
         function emitPos(pos: number) {
-            if (positionIsSynthesized(pos) || disableDepth > 0) {
+            if (disabled || positionIsSynthesized(pos)) {
                 return;
             }
 
@@ -495,209 +293,89 @@ namespace ts {
                     sourceColumn: sourceLinePos.character,
                     sourceIndex: sourceMapSourceIndex
                 };
-
-                stopOverridingSpan = false;
             }
-            else if (!stopOverridingSpan) {
+            else {
                 // Take the new pos instead since there is no change in emittedLine and column since last location
                 lastRecordedSourceMapSpan.sourceLine = sourceLinePos.line;
                 lastRecordedSourceMapSpan.sourceColumn = sourceLinePos.character;
                 lastRecordedSourceMapSpan.sourceIndex = sourceMapSourceIndex;
             }
 
-            updateLastEncodedAndRecordedSpans();
-
             if (extendedDiagnostics) {
                 performance.mark("afterSourcemap");
                 performance.measure("Source Map", "beforeSourcemap", "afterSourcemap");
             }
         }
 
-        function getStartPosPastDecorators(range: TextRange) {
-            const rangeHasDecorators = !!(range as Node).decorators;
-            return skipTrivia(currentSourceText, rangeHasDecorators ? (range as Node).decorators.end : range.pos);
-        }
-
         /**
-         * Emits a mapping for the start of a range.
+         * Emits a node with possible leading and trailing source maps.
          *
-         * If the range's start position is synthetic (undefined or a negative value), no mapping
-         * will be created. Any trivia at the start position in the original source will be
-         * skipped.
-         *
-         * @param range The range to emit.0
+         * @param node The node to emit.
+         * @param emitCallback The callback used to emit the node.
          */
-        function emitStart(range: TextRange): void;
-        /**
-         * Emits a mapping for the start of a range.
-         *
-         * If the node's start position is synthetic (undefined or a negative value), no mapping
-         * will be created. Any trivia at the start position in the original source will be
-         * skipped.
-         *
-         * @param range The range to emit.
-         * @param contextNode The node for the current range.
-         * @param ignoreNodeCallback A callback used to determine whether to skip source map
-         *        emit for the start position of this node.
-         * @param ignoreChildrenCallback A callback used to determine whether to skip source
-         *        map emit for all children of this node.
-         * @param getTextRangeCallbackCallback A callback used to get a custom source map
-         *        range for this node.
-         */
-        function emitStart(range: TextRange, contextNode: Node, ignoreNodeCallback: (node: Node) => boolean, ignoreChildrenCallback: (node: Node) => boolean, getTextRangeCallback: (node: Node) => TextRange): void;
-        function emitStart(range: TextRange, contextNode?: Node, ignoreNodeCallback?: (node: Node) => boolean, ignoreChildrenCallback?: (node: Node) => boolean, getTextRangeCallback?: (node: Node) => TextRange) {
-            if (contextNode) {
-                if (!ignoreNodeCallback(contextNode)) {
-                    range = getTextRangeCallback(contextNode) || range;
-                    emitPos(getStartPosPastDecorators(range));
-                }
-
-                if (ignoreChildrenCallback(contextNode)) {
-                    disable();
-                }
+        function emitNodeWithSourceMap(node: Node, emitCallback: (node: Node) => void) {
+            if (disabled) {
+                return emitCallback(node);
             }
-            else {
-                emitPos(getStartPosPastDecorators(range));
+
+            if (node) {
+                const emitNode = node.emitNode;
+                const emitFlags = emitNode && emitNode.flags;
+                const { pos, end } = emitNode && emitNode.sourceMapRange || node;
+
+                if (node.kind !== SyntaxKind.NotEmittedStatement
+                    && (emitFlags & EmitFlags.NoLeadingSourceMap) === 0
+                    && pos >= 0) {
+                    emitPos(skipTrivia(currentSourceText, pos));
+                }
+
+                if (emitFlags & EmitFlags.NoNestedSourceMaps) {
+                    disabled = true;
+                    emitCallback(node);
+                    disabled = false;
+                }
+                else {
+                    emitCallback(node);
+                }
+
+                if (node.kind !== SyntaxKind.NotEmittedStatement
+                    && (emitFlags & EmitFlags.NoTrailingSourceMap) === 0
+                    && end >= 0) {
+                    emitPos(end);
+                }
             }
         }
 
         /**
-         * Emits a mapping for the end of a range.
-         *
-         * If the range's end position is synthetic (undefined or a negative value), no mapping
-         * will be created.
-         *
-         * @param range The range to emit.
-         */
-        function emitEnd(range: TextRange): void;
-        /**
-         * Emits a mapping for the end of a range.
-         *
-         * If the node's end position is synthetic (undefined or a negative value), no mapping
-         * will be created.
-         *
-         * @param range The range to emit.
-         * @param contextNode The node for the current range.
-         * @param ignoreNodeCallback A callback used to determine whether to skip source map
-         *        emit for the end position of this node.
-         * @param ignoreChildrenCallback A callback used to determine whether to skip source
-         *        map emit for all children of this node.
-         * @param getTextRangeCallbackCallback A callback used to get a custom source map
-         *        range for this node.
-         */
-        function emitEnd(range: TextRange, contextNode: Node, ignoreNodeCallback: (node: Node) => boolean, ignoreChildrenCallback: (node: Node) => boolean, getTextRangeCallback: (node: Node) => TextRange): void;
-        function emitEnd(range: TextRange, contextNode?: Node, ignoreNodeCallback?: (node: Node) => boolean, ignoreChildrenCallback?: (node: Node) => boolean, getTextRangeCallback?: (node: Node) => TextRange) {
-            if (contextNode) {
-                if (ignoreChildrenCallback(contextNode)) {
-                    enable();
-                }
-
-                if (!ignoreNodeCallback(contextNode)) {
-                    range = getTextRangeCallback(contextNode) || range;
-                    emitPos(range.end);
-                }
-            }
-            else {
-                emitPos(range.end);
-            }
-
-            stopOverridingSpan = false;
-        }
-
-        /**
-         * Emits a mapping for the start position of a token.
-         *
-         * If the token's start position is synthetic (undefined or a negative value), no mapping
-         * will be created. Any trivia at the start position in the original source will be
-         * skipped.
+         * Emits a token of a node node with possible leading and trailing source maps.
          *
+         * @param node The node containing the token.
          * @param token The token to emit.
-         * @param tokenStartPos The start position of the token.
-         * @returns The start position of the token, following any trivia.
+         * @param tokenStartPos The start pos of the token.
+         * @param emitCallback The callback used to emit the token.
          */
-        function emitTokenStart(token: SyntaxKind, tokenStartPos: number): number;
-        /**
-         * Emits a mapping for the start position of a token.
-         *
-         * If the token's start position is synthetic (undefined or a negative value), no mapping
-         * will be created. Any trivia at the start position in the original source will be
-         * skipped.
-         *
-         * @param token The token to emit.
-         * @param tokenStartPos The start position of the token.
-         * @param contextNode The node containing this token.
-         * @param ignoreTokenCallback A callback used to determine whether to skip source map
-         *        emit for the start position of this token.
-         * @param getTokenTextRangeCallback A callback used to get a custom source
-         *        map range for this node.
-         * @returns The start position of the token, following any trivia.
-         */
-        function emitTokenStart(token: SyntaxKind, tokenStartPos: number, contextNode: Node, ignoreTokenCallback: (node: Node, token: SyntaxKind) => boolean, getTokenTextRangeCallback: (node: Node, token: SyntaxKind) => TextRange): number;
-        function emitTokenStart(token: SyntaxKind, tokenStartPos: number, contextNode?: Node, ignoreTokenCallback?: (node: Node, token: SyntaxKind) => boolean, getTokenTextRangeCallback?: (node: Node, token: SyntaxKind) => TextRange): number {
-            if (contextNode) {
-                if (ignoreTokenCallback(contextNode, token)) {
-                    return skipTrivia(currentSourceText, tokenStartPos);
-                }
-
-                const range = getTokenTextRangeCallback(contextNode, token);
-                if (range) {
-                    tokenStartPos = range.pos;
-                }
+        function emitTokenWithSourceMap(node: Node, token: SyntaxKind, tokenPos: number, emitCallback: (token: SyntaxKind, tokenStartPos: number) => number) {
+            if (disabled) {
+                return emitCallback(token, tokenPos);
             }
 
-            tokenStartPos = skipTrivia(currentSourceText, tokenStartPos);
-            emitPos(tokenStartPos);
-            return tokenStartPos;
-        }
+            const emitNode = node && node.emitNode;
+            const emitFlags = emitNode && emitNode.flags;
+            const range = emitNode && emitNode.tokenSourceMapRanges && emitNode.tokenSourceMapRanges[token];
 
-        /**
-         * Emits a mapping for the end position of a token.
-         *
-         * If the token's end position is synthetic (undefined or a negative value), no mapping
-         * will be created.
-         *
-         * @param token The token to emit.
-         * @param tokenEndPos The end position of the token.
-         * @returns The end position of the token.
-         */
-        function emitTokenEnd(token: SyntaxKind, tokenEndPos: number): number;
-        /**
-         * Emits a mapping for the end position of a token.
-         *
-         * If the token's end position is synthetic (undefined or a negative value), no mapping
-         * will be created.
-         *
-         * @param token The token to emit.
-         * @param tokenEndPos The end position of the token.
-         * @param contextNode The node containing this token.
-         * @param ignoreTokenCallback A callback used to determine whether to skip source map
-         *        emit for the end position of this token.
-         * @param getTokenTextRangeCallback A callback used to get a custom source
-         *        map range for this node.
-         * @returns The end position of the token.
-         */
-        function emitTokenEnd(token: SyntaxKind, tokenEndPos: number, contextNode: Node, ignoreTokenCallback: (node: Node, token: SyntaxKind) => boolean, getTokenTextRangeCallback: (node: Node, token: SyntaxKind) => TextRange): number;
-        function emitTokenEnd(token: SyntaxKind, tokenEndPos: number, contextNode?: Node, ignoreTokenCallback?: (node: Node, token: SyntaxKind) => boolean, getTokenTextRangeCallback?: (node: Node, token: SyntaxKind) => TextRange): number {
-            if (contextNode) {
-                if (ignoreTokenCallback(contextNode, token)) {
-                    return tokenEndPos;
-                }
-
-                const range = getTokenTextRangeCallback(contextNode, token);
-                if (range) {
-                    tokenEndPos = range.end;
-                }
+            tokenPos = skipTrivia(currentSourceText, range ? range.pos : tokenPos);
+            if ((emitFlags & EmitFlags.NoTokenLeadingSourceMaps) === 0 && tokenPos >= 0) {
+                emitPos(tokenPos);
             }
 
-            emitPos(tokenEndPos);
-            return tokenEndPos;
-        }
+            tokenPos = emitCallback(token, tokenPos);
 
+            if (range) tokenPos = range.end;
+            if ((emitFlags & EmitFlags.NoTokenTrailingSourceMaps) === 0 && tokenPos >= 0) {
+                emitPos(tokenPos);
+            }
 
-        // @deprecated
-        function changeEmitSourcePos() {
-            Debug.assert(!modifyLastSourcePos);
-            modifyLastSourcePos = true;
+            return tokenPos;
         }
 
         /**
@@ -706,6 +384,10 @@ namespace ts {
          * @param sourceFile The source file.
          */
         function setSourceFile(sourceFile: SourceFile) {
+            if (disabled) {
+                return;
+            }
+
             currentSourceFile = sourceFile;
             currentSourceText = currentSourceFile.text;
 
@@ -738,6 +420,10 @@ namespace ts {
          * Gets the text for the source map.
          */
         function getText() {
+            if (disabled) {
+                return;
+            }
+
             encodeLastRecordedSourceMapSpan();
 
             return stringify({
@@ -755,6 +441,10 @@ namespace ts {
          * Gets the SourceMappingURL for the source map.
          */
         function getSourceMappingURL() {
+            if (disabled) {
+                return;
+            }
+
             if (compilerOptions.inlineSourceMap) {
                 // Encode the sourceMap into the sourceMap url
                 const base64SourceMapText = convertToBase64(getText());
@@ -766,61 +456,6 @@ namespace ts {
         }
     }
 
-    function createSourceMapWriterWithExtendedDiagnostics(host: EmitHost, writer: EmitTextWriter): SourceMapWriter {
-        const {
-            initialize,
-            reset,
-            getSourceMapData,
-            setSourceFile,
-            emitPos,
-            emitStart,
-            emitEnd,
-            emitTokenStart,
-            emitTokenEnd,
-            changeEmitSourcePos,
-            stopOverridingSpan,
-            getText,
-            getSourceMappingURL,
-        } = createSourceMapWriterWorker(host, writer);
-        return {
-            initialize,
-            reset,
-            getSourceMapData,
-            setSourceFile,
-            emitPos(pos: number): void {
-                 performance.mark("sourcemapStart");
-                emitPos(pos);
-                performance.measure("sourceMapTime", "sourcemapStart");
-            },
-            emitStart(range: TextRange, contextNode?: Node, ignoreNodeCallback?: (node: Node) => boolean, ignoreChildrenCallback?: (node: Node) => boolean, getTextRangeCallback?: (node: Node) => TextRange): void {
-                performance.mark("emitSourcemap:emitStart");
-                emitStart(range, contextNode, ignoreNodeCallback, ignoreChildrenCallback, getTextRangeCallback);
-                performance.measure("sourceMapTime", "emitSourcemap:emitStart");
-            },
-            emitEnd(range: TextRange, contextNode?: Node, ignoreNodeCallback?: (node: Node) => boolean, ignoreChildrenCallback?: (node: Node) => boolean, getTextRangeCallback?: (node: Node) => TextRange): void {
-                performance.mark("emitSourcemap:emitEnd");
-                emitEnd(range, contextNode, ignoreNodeCallback, ignoreChildrenCallback, getTextRangeCallback);
-                performance.measure("sourceMapTime", "emitSourcemap:emitEnd");
-            },
-            emitTokenStart(token: SyntaxKind, tokenStartPos: number, contextNode?: Node, ignoreTokenCallback?: (node: Node) => boolean, getTokenTextRangeCallback?: (node: Node, token: SyntaxKind) => TextRange): number {
-                performance.mark("emitSourcemap:emitTokenStart");
-                tokenStartPos = emitTokenStart(token, tokenStartPos, contextNode, ignoreTokenCallback, getTokenTextRangeCallback);
-                performance.measure("sourceMapTime", "emitSourcemap:emitTokenStart");
-                return tokenStartPos;
-            },
-            emitTokenEnd(token: SyntaxKind, tokenEndPos: number, contextNode?: Node, ignoreTokenCallback?: (node: Node) => boolean, getTokenTextRangeCallback?: (node: Node, token: SyntaxKind) => TextRange): number {
-                performance.mark("emitSourcemap:emitTokenEnd");
-                tokenEndPos = emitTokenEnd(token, tokenEndPos, contextNode, ignoreTokenCallback, getTokenTextRangeCallback);
-                performance.measure("sourceMapTime", "emitSourcemap:emitTokenEnd");
-                return tokenEndPos;
-            },
-            changeEmitSourcePos,
-            stopOverridingSpan,
-            getText,
-            getSourceMappingURL,
-        };
-    }
-
     const base64Chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
 
     function base64FormatEncode(inValue: number) {
diff --git a/src/compiler/transformer.ts b/src/compiler/transformer.ts
index 8c6fae458f0..5695bea7ae9 100644
--- a/src/compiler/transformer.ts
+++ b/src/compiler/transformer.ts
@@ -31,33 +31,21 @@ namespace ts {
         getSourceFiles(): SourceFile[];
 
         /**
-         * Determines whether expression substitutions are enabled for the provided node.
-         */
-        isSubstitutionEnabled(node: Node): boolean;
-
-        /**
-         * Determines whether before/after emit notifications should be raised in the pretty
-         * printer when it emits a node.
-         */
-        isEmitNotificationEnabled(node: Node): boolean;
-
-        /**
-         * Hook used by transformers to substitute expressions just before they
-         * are emitted by the pretty printer.
+         * Emits the substitute for a node, if one is available; otherwise, emits the node.
          *
          * @param node The node to substitute.
          * @param isExpression A value indicating whether the node is in an expression context.
+         * @param emitCallback A callback used to emit the node or its substitute.
          */
-        onSubstituteNode(node: Node, isExpression: boolean): Node;
+        emitNodeWithSubstitution(node: Node, isExpression: boolean, emitCallback: (node: Node) => void): void;
 
         /**
-         * Hook used to allow transformers to capture state before or after
-         * the printer emits a node.
+         * Emits a node with possible notification.
          *
          * @param node The node to emit.
          * @param emitCallback A callback used to emit the node.
          */
-        onEmitNode(node: Node, emitCallback: (node: Node) => void): void;
+        emitNodeWithNotification(node: Node, emitCallback: (node: Node) => void): void;
 
         /**
          * Reset transient transformation properties on parse tree nodes.
@@ -302,10 +290,10 @@ namespace ts {
             hoistFunctionDeclaration,
             startLexicalEnvironment,
             endLexicalEnvironment,
-            onSubstituteNode,
+            onSubstituteNode: (node, isExpression) => node,
             enableSubstitution,
             isSubstitutionEnabled,
-            onEmitNode,
+            onEmitNode: (node, emitCallback) => emitCallback(node),
             enableEmitNotification,
             isEmitNotificationEnabled
         };
@@ -321,10 +309,8 @@ namespace ts {
 
         return {
             getSourceFiles: () => transformed,
-            isSubstitutionEnabled,
-            isEmitNotificationEnabled,
-            onSubstituteNode: context.onSubstituteNode,
-            onEmitNode: context.onEmitNode,
+            emitNodeWithSubstitution,
+            emitNodeWithNotification,
             dispose() {
                 // During transformation we may need to annotate a parse tree node with transient
                 // transformation properties. As parse tree nodes live longer than transformation
@@ -362,18 +348,29 @@ namespace ts {
          * Determines whether expression substitutions are enabled for the provided node.
          */
         function isSubstitutionEnabled(node: Node) {
-            return (enabledSyntaxKindFeatures[node.kind] & SyntaxKindFeatureFlags.Substitution) !== 0;
+            return (enabledSyntaxKindFeatures[node.kind] & SyntaxKindFeatureFlags.Substitution) !== 0
+                && (getEmitFlags(node) & EmitFlags.NoSubstitution) === 0;
         }
 
         /**
-         * Default hook for node substitutions.
+         * Emits a node with possible substitution.
          *
-         * @param node The node to substitute.
-         * @param isExpression A value indicating whether the node is to be used in an expression
-         *                     position.
+         * @param node The node to emit.
+         * @param isExpression Whether the node represents an expression.
+         * @param emitCallback The callback used to emit the node or its substitute.
          */
-        function onSubstituteNode(node: Node, isExpression: boolean) {
-            return node;
+        function emitNodeWithSubstitution(node: Node, isExpression: boolean, emitCallback: (node: Node) => void) {
+            if (node) {
+                if (isSubstitutionEnabled(node)) {
+                    const substitute = context.onSubstituteNode(node, isExpression);
+                    if (substitute && substitute !== node) {
+                        emitCallback(substitute);
+                        return;
+                    }
+                }
+
+                emitCallback(node);
+            }
         }
 
         /**
@@ -393,13 +390,17 @@ namespace ts {
         }
 
         /**
-         * Default hook for node emit.
-         *
-         * @param node The node to emit.
-         * @param emit A callback used to emit the node in the printer.
+         * Emits a node with possible emit notification.
          */
-        function onEmitNode(node: Node, emit: (node: Node) => void) {
-            emit(node);
+        function emitNodeWithNotification(node: Node, emitCallback: (node: Node) => void) {
+            if (node) {
+                if (isEmitNotificationEnabled(node)) {
+                    context.onEmitNode(node, emitCallback);
+                }
+                else {
+                    emitCallback(node);
+                }
+            }
         }
 
         /**

From bfb8933a9392c17344354487cb1f29c73aa343d3 Mon Sep 17 00:00:00 2001
From: Ron Buckton <rbuckton@microsoft.com>
Date: Mon, 26 Sep 2016 15:21:03 -0700
Subject: [PATCH 34/47] Refactored emit pipeline.

---
 src/compiler/comments.ts                   |  35 ++--
 src/compiler/emitter.ts                    | 219 +++++++++++----------
 src/compiler/factory.ts                    | 135 ++++++++++++-
 src/compiler/sourcemap.ts                  |  11 +-
 src/compiler/transformer.ts                | 190 +++---------------
 src/compiler/transformers/es6.ts           |  10 +-
 src/compiler/transformers/generators.ts    |   6 +-
 src/compiler/transformers/module/module.ts |  12 +-
 src/compiler/transformers/module/system.ts |  12 +-
 src/compiler/transformers/ts.ts            |  10 +-
 src/compiler/types.ts                      |   8 +
 11 files changed, 326 insertions(+), 322 deletions(-)

diff --git a/src/compiler/comments.ts b/src/compiler/comments.ts
index f9f8e74d4ca..116a8e849a3 100644
--- a/src/compiler/comments.ts
+++ b/src/compiler/comments.ts
@@ -5,7 +5,7 @@ namespace ts {
     export interface CommentWriter {
         reset(): void;
         setSourceFile(sourceFile: SourceFile): void;
-        emitNodeWithComments(node: Node, emitCallback: (node: Node) => void): void;
+        emitNodeWithComments(emitContext: EmitContext, node: Node, emitCallback: (emitContext: EmitContext, node: Node) => void): void;
         emitBodyWithDetachedComments(node: Node, detachedRange: TextRange, emitCallback: (node: Node) => void): void;
         emitTrailingCommentsOfPosition(pos: number): void;
     }
@@ -34,9 +34,9 @@ namespace ts {
             emitTrailingCommentsOfPosition,
         };
 
-        function emitNodeWithComments(node: Node, emitCallback: (node: Node) => void) {
+        function emitNodeWithComments(emitContext: EmitContext, node: Node, emitCallback: (emitContext: EmitContext, node: Node) => void) {
             if (disabled) {
-                emitCallback(node);
+                emitCallback(emitContext, node);
                 return;
             }
 
@@ -46,10 +46,12 @@ namespace ts {
                 if ((pos < 0 && end < 0) || (pos === end)) {
                     // Both pos and end are synthesized, so just emit the node without comments.
                     if (emitFlags & EmitFlags.NoNestedComments) {
-                        disableCommentsAndEmit(node, emitCallback);
+                        disabled = true;
+                        emitCallback(emitContext, node);
+                        disabled = false;
                     }
                     else {
-                        emitCallback(node);
+                        emitCallback(emitContext, node);
                     }
                 }
                 else {
@@ -91,10 +93,12 @@ namespace ts {
                     }
 
                     if (emitFlags & EmitFlags.NoNestedComments) {
-                        disableCommentsAndEmit(node, emitCallback);
+                        disabled = true;
+                        emitCallback(emitContext, node);
+                        disabled = false;
                     }
                     else {
-                        emitCallback(node);
+                        emitCallback(emitContext, node);
                     }
 
                     if (extendedDiagnostics) {
@@ -137,8 +141,10 @@ namespace ts {
                 performance.measure("commentTime", "preEmitBodyWithDetachedComments");
             }
 
-            if (emitFlags & EmitFlags.NoNestedComments) {
-                disableCommentsAndEmit(node, emitCallback);
+            if (emitFlags & EmitFlags.NoNestedComments && !disabled) {
+                disabled = true;
+                emitCallback(node);
+                disabled = false;
             }
             else {
                 emitCallback(node);
@@ -284,17 +290,6 @@ namespace ts {
             detachedCommentsInfo = undefined;
         }
 
-        function disableCommentsAndEmit(node: Node, emitCallback: (node: Node) => void): void {
-            if (disabled) {
-                emitCallback(node);
-            }
-            else {
-                disabled = true;
-                emitCallback(node);
-                disabled = false;
-            }
-        }
-
         function hasDetachedComments(pos: number) {
             return detachedCommentsInfo !== undefined && lastOrUndefined(detachedCommentsInfo).nodePos === pos;
         }
diff --git a/src/compiler/emitter.ts b/src/compiler/emitter.ts
index 8457ea41d02..03f785dc7de 100644
--- a/src/compiler/emitter.ts
+++ b/src/compiler/emitter.ts
@@ -229,33 +229,27 @@ const _super = (function (geti, seti) {
         let isOwnFileEmit: boolean;
         let emitSkipped = false;
 
-        performance.mark("beforeTransform");
+        const sourceFiles = getSourceFilesToEmit(host, targetSourceFile);
 
         // Transform the source files
-        const transformed = transformFiles(
-            resolver,
-            host,
-            getSourceFilesToEmit(host, targetSourceFile),
-            transformers);
-
-        performance.measure("transformTime", "beforeTransform");
-
-        // Extract helpers from the result
+        performance.mark("beforeTransform");
         const {
+            transformed,
             emitNodeWithSubstitution,
             emitNodeWithNotification
-        } = transformed;
-
-        performance.mark("beforePrint");
+        } = transformFiles(resolver, host, sourceFiles, transformers);
+        performance.measure("transformTime", "beforeTransform");
 
         // Emit each output file
-        forEachTransformedEmitFile(host, transformed.getSourceFiles(), emitFile);
-
-        // Clean up after transformation
-        transformed.dispose();
-
+        performance.mark("beforePrint");
+        forEachTransformedEmitFile(host, transformed, emitFile);
         performance.measure("printTime", "beforePrint");
 
+        // Clean up emit nodes on parse tree
+        for (const sourceFile of sourceFiles) {
+            disposeEmitNodes(sourceFile);
+        }
+
         return {
             emitSkipped,
             diagnostics: emitterDiagnostics.getDiagnostics(),
@@ -346,111 +340,137 @@ const _super = (function (geti, seti) {
             currentFileIdentifiers = node.identifiers;
             sourceMap.setSourceFile(node);
             comments.setSourceFile(node);
-            emitNodeWithNotification(node, emitWithSubstitution);
+            pipelineEmitWithNotification(EmitContext.SourceFile, node);
         }
 
         /**
          * Emits a node.
          */
         function emit(node: Node) {
-            emitNodeWithNotification(node, emitWithComments);
-        }
-
-        /**
-         * Emits a node with comments.
-         *
-         * NOTE: Do not call this method directly. It is part of the emit pipeline
-         * and should only be called indirectly from emit.
-         */
-        function emitWithComments(node: Node) {
-            emitNodeWithComments(node, emitWithSourceMap);
-        }
-
-        /**
-         * Emits a node with source maps.
-         *
-         * NOTE: Do not call this method directly. It is part of the emit pipeline
-         * and should only be called indirectly from emitWithComments.
-         */
-        function emitWithSourceMap(node: Node) {
-            emitNodeWithSourceMap(node, emitWithSubstitution);
-        }
-
-        /**
-         * Emits a node with possible substitution.
-         *
-         * NOTE: Do not call this method directly. It is part of the emit pipeline
-         * and should only be called indirectly from emitWithSourceMap or
-         * emitIdentifierNameWithComments.
-         */
-        function emitWithSubstitution(node: Node) {
-            emitNodeWithSubstitution(node, /*isExpression*/ false, emitWorker);
+            pipelineEmitWithNotification(EmitContext.Unspecified, node);
         }
 
         /**
          * Emits an IdentifierName.
          */
         function emitIdentifierName(node: Identifier) {
-            if (node) {
-                emitNodeWithNotification(node, emitIdentifierNameWithComments);
-            }
-        }
-
-        /**
-         * Emits an IdentifierName with possible comments.
-         *
-         * NOTE: Do not call this method directly. It is part of the emit pipeline
-         * and should only be called indirectly from emitIdentifierName.
-         */
-        function emitIdentifierNameWithComments(node: Identifier) {
-            emitNodeWithComments(node, emitWithSubstitution);
+            pipelineEmitWithNotification(EmitContext.IdentifierName, node);
         }
 
         /**
          * Emits an expression node.
          */
         function emitExpression(node: Expression) {
-            emitNodeWithNotification(node, emitExpressionWithComments);
+            pipelineEmitWithNotification(EmitContext.Expression, node);
         }
 
         /**
-         * Emits an expression with comments.
+         * Emits a node with possible notification.
          *
-         * NOTE: Do not call this method directly. It is part of the emitExpression pipeline
-         * and should only be called indirectly from emitExpression.
+         * NOTE: Do not call this method directly. It is part of the emit pipeline
+         * and should only be called from printSourceFile, emit, emitExpression, or
+         * emitIdentifierName.
          */
-        function emitExpressionWithComments(node: Expression) {
-            emitNodeWithComments(node, emitExpressionWithSourceMap);
+        function pipelineEmitWithNotification(emitContext: EmitContext, node: Node) {
+            emitNodeWithNotification(emitContext, node, pipelineEmitWithComments);
         }
 
         /**
-         * Emits an expression with possible source maps.
+         * Emits a node with comments.
          *
-         * NOTE: Do not call this method directly. It is part of the emitExpression pipeline
-         * and should only be called indirectly from emitExpressionWithComments.
+         * NOTE: Do not call this method directly. It is part of the emit pipeline
+         * and should only be called indirectly from pipelineEmitWithNotification.
          */
-        function emitExpressionWithSourceMap(node: Expression) {
-            emitNodeWithSourceMap(node, emitExpressionWithSubstitution);
+        function pipelineEmitWithComments(emitContext: EmitContext, node: Node) {
+            // Do not emit comments for SourceFile
+            if (emitContext === EmitContext.SourceFile) {
+                pipelineEmitWithSourceMap(emitContext, node);
+                return;
+            }
+
+            emitNodeWithComments(emitContext, node, pipelineEmitWithSourceMap);
         }
 
         /**
-         * Emits an expression with possible substitution.
+         * Emits a node with source maps.
          *
-         * NOTE: Do not call this method directly. It is part of the emitExpression pipeline
-         * and should only be called indirectly from emitExpressionWithSourceMap or
-         * from emitWorker.
+         * NOTE: Do not call this method directly. It is part of the emit pipeline
+         * and should only be called indirectly from pipelineEmitWithComments.
          */
-        function emitExpressionWithSubstitution(node: Expression) {
-            emitNodeWithSubstitution(node, /*isExpression*/ true, emitExpressionWorker);
+        function pipelineEmitWithSourceMap(emitContext: EmitContext, node: Node) {
+            // Do not emit source mappings for SourceFile or IdentifierName
+            if (emitContext === EmitContext.SourceFile
+                || emitContext === EmitContext.IdentifierName) {
+                pipelineEmitWithSubstitution(emitContext, node);
+                return;
+            }
+
+            emitNodeWithSourceMap(emitContext, node, pipelineEmitWithSubstitution);
+        }
+
+        /**
+         * Emits a node with possible substitution.
+         *
+         * NOTE: Do not call this method directly. It is part of the emit pipeline
+         * and should only be called indirectly from pipelineEmitWithSourceMap or
+         * pipelineEmitInUnspecifiedContext (when pickign a more specific context).
+         */
+        function pipelineEmitWithSubstitution(emitContext: EmitContext, node: Node) {
+            emitNodeWithSubstitution(emitContext, node, pipelineEmitForContext);
         }
 
         /**
          * Emits a node.
          *
          * NOTE: Do not call this method directly. It is part of the emit pipeline
-         * and should only be called indirectly from emitNodeWithSubstitution.
+         * and should only be called indirectly from pipelineEmitWithSubstitution.
          */
-        function emitWorker(node: Node): void {
+        function pipelineEmitForContext(emitContext: EmitContext, node: Node): void {
+            switch (emitContext) {
+                case EmitContext.SourceFile: return pipelineEmitInSourceFileContext(node);
+                case EmitContext.IdentifierName: return pipelineEmitInIdentifierNameContext(node);
+                case EmitContext.Unspecified: return pipelineEmitInUnspecifiedContext(node);
+                case EmitContext.Expression: return pipelineEmitInExpressionContext(node);
+            }
+        }
+
+        /**
+         * Emits a node in the SourceFile EmitContext.
+         *
+         * NOTE: Do not call this method directly. It is part of the emit pipeline
+         * and should only be called indirectly from pipelineEmitForContext.
+         */
+        function pipelineEmitInSourceFileContext(node: Node): void {
+            const kind = node.kind;
+            switch (kind) {
+                // Top-level nodes
+                case SyntaxKind.SourceFile:
+                    return emitSourceFile(<SourceFile>node);
+            }
+        }
+
+        /**
+         * Emits a node in the IdentifierName EmitContext.
+         *
+         * NOTE: Do not call this method directly. It is part of the emit pipeline
+         * and should only be called indirectly from pipelineEmitForContext.
+         */
+        function pipelineEmitInIdentifierNameContext(node: Node): void {
+            const kind = node.kind;
+            switch (kind) {
+                // Identifiers
+                case SyntaxKind.Identifier:
+                    return emitIdentifier(<Identifier>node);
+            }
+        }
+
+        /**
+         * Emits a node in the Unspecified EmitContext.
+         *
+         * NOTE: Do not call this method directly. It is part of the emit pipeline
+         * and should only be called indirectly from pipelineEmitForContext.
+         */
+        function pipelineEmitInUnspecifiedContext(node: Node): void {
             const kind = node.kind;
             switch (kind) {
                 // Pseudo-literals
@@ -486,7 +506,8 @@ const _super = (function (geti, seti) {
                 case SyntaxKind.StringKeyword:
                 case SyntaxKind.SymbolKeyword:
                 case SyntaxKind.GlobalKeyword:
-                    return emitTokenNode(node);
+                    writeTokenText(kind);
+                    return;
 
                 // Parse tree nodes
 
@@ -691,27 +712,24 @@ const _super = (function (geti, seti) {
                 case SyntaxKind.EnumMember:
                     return emitEnumMember(<EnumMember>node);
 
-                // Top-level nodes
-                case SyntaxKind.SourceFile:
-                    return emitSourceFile(<SourceFile>node);
-
                 // JSDoc nodes (ignored)
-
                 // Transformation nodes (ignored)
             }
 
+            // If the node is an expression, try to emit it as an expression with
+            // substitution.
             if (isExpression(node)) {
-                return emitExpressionWithSubstitution(node);
+                return pipelineEmitWithSubstitution(EmitContext.Expression, node);
             }
         }
 
         /**
-         * Emits an expression.
+         * Emits a node in the Expression EmitContext.
          *
-         * NOTE: Do not call this method directly. It is part of the emitExpression pipeline
-         * and should only be called indirectly from emitExpressionWithNotification.
+         * NOTE: Do not call this method directly. It is part of the emit pipeline
+         * and should only be called indirectly from pipelineEmitForContext.
          */
-        function emitExpressionWorker(node: Node) {
+        function pipelineEmitInExpressionContext(node: Node): void {
             const kind = node.kind;
             switch (kind) {
                 // Literals
@@ -733,7 +751,8 @@ const _super = (function (geti, seti) {
                 case SyntaxKind.SuperKeyword:
                 case SyntaxKind.TrueKeyword:
                 case SyntaxKind.ThisKeyword:
-                    return emitTokenNode(node);
+                    writeTokenText(kind);
+                    return;
 
                 // Expressions
                 case SyntaxKind.ArrayLiteralExpression:
@@ -2444,15 +2463,7 @@ const _super = (function (geti, seti) {
         function writeTokenText(token: SyntaxKind, pos?: number) {
             const tokenString = tokenToString(token);
             write(tokenString);
-            return positionIsSynthesized(pos) ? -1 : pos + tokenString.length;
-        }
-
-        function emitTokenNode(node: Node) {
-            emitNodeWithSourceMap(node, emitTokenNodeWorker);
-        }
-
-        function emitTokenNodeWorker(node: Node) {
-            writeTokenText(node.kind);
+            return pos < 0 ? pos : pos + tokenString.length;
         }
 
         function increaseIndentIf(value: boolean, valueToWriteWhenNotIndenting?: string) {
diff --git a/src/compiler/factory.ts b/src/compiler/factory.ts
index c0565f6e91d..b6fc2093288 100644
--- a/src/compiler/factory.ts
+++ b/src/compiler/factory.ts
@@ -2665,6 +2665,139 @@ namespace ts {
         return destRanges;
     }
 
+    /**
+     * Clears any EmitNode entries from parse-tree nodes.
+     * @param sourceFile A source file.
+     */
+    export function disposeEmitNodes(sourceFile: SourceFile) {
+        // During transformation we may need to annotate a parse tree node with transient
+        // transformation properties. As parse tree nodes live longer than transformation
+        // nodes, we need to make sure we reclaim any memory allocated for custom ranges
+        // from these nodes to ensure we do not hold onto entire subtrees just for position
+        // information. We also need to reset these nodes to a pre-transformation state
+        // for incremental parsing scenarios so that we do not impact later emit.
+        sourceFile = getSourceFileOfNode(getParseTreeNode(sourceFile));
+        const emitNode = sourceFile && sourceFile.emitNode;
+        const annotatedNodes = emitNode && emitNode.annotatedNodes;
+        if (annotatedNodes) {
+            for (const node of annotatedNodes) {
+                node.emitNode = undefined;
+            }
+        }
+    }
+
+    /**
+     * Associates a node with the current transformation, initializing
+     * various transient transformation properties.
+     *
+     * @param node The node.
+     */
+    function getOrCreateEmitNode(node: Node) {
+        if (!node.emitNode) {
+            if (isParseTreeNode(node)) {
+                // To avoid holding onto transformation artifacts, we keep track of any
+                // parse tree node we are annotating. This allows us to clean them up after
+                // all transformations have completed.
+                if (node.kind === SyntaxKind.SourceFile) {
+                    return node.emitNode = { annotatedNodes: [node] };
+                }
+
+                const sourceFile = getSourceFileOfNode(node);
+                getOrCreateEmitNode(sourceFile).annotatedNodes.push(node);
+            }
+
+            node.emitNode = {};
+        }
+
+        return node.emitNode;
+    }
+
+    /**
+     * Gets flags that control emit behavior of a node.
+     *
+     * @param node The node.
+     */
+    export function getEmitFlags(node: Node) {
+        const emitNode = node.emitNode;
+        return emitNode && emitNode.flags;
+    }
+
+    /**
+     * Sets flags that control emit behavior of a node.
+     *
+     * @param node The node.
+     * @param emitFlags The NodeEmitFlags for the node.
+     */
+    export function setEmitFlags<T extends Node>(node: T, emitFlags: EmitFlags) {
+        getOrCreateEmitNode(node).flags = emitFlags;
+        return node;
+    }
+
+    /**
+     * Sets a custom text range to use when emitting source maps.
+     *
+     * @param node The node.
+     * @param range The text range.
+     */
+    export function setSourceMapRange<T extends Node>(node: T, range: TextRange) {
+        getOrCreateEmitNode(node).sourceMapRange = range;
+        return node;
+    }
+
+    /**
+     * Sets the TextRange to use for source maps for a token of a node.
+     *
+     * @param node The node.
+     * @param token The token.
+     * @param range The text range.
+     */
+    export function setTokenSourceMapRange<T extends Node>(node: T, token: SyntaxKind, range: TextRange) {
+        const emitNode = getOrCreateEmitNode(node);
+        const tokenSourceMapRanges = emitNode.tokenSourceMapRanges || (emitNode.tokenSourceMapRanges = createMap<TextRange>());
+        tokenSourceMapRanges[token] = range;
+        return node;
+    }
+
+    /**
+     * Sets a custom text range to use when emitting comments.
+     */
+    export function setCommentRange<T extends Node>(node: T, range: TextRange) {
+        getOrCreateEmitNode(node).commentRange = range;
+        return node;
+    }
+
+    /**
+     * Gets a custom text range to use when emitting comments.
+     *
+     * @param node The node.
+     */
+    export function getCommentRange(node: Node) {
+        const emitNode = node.emitNode;
+        return (emitNode && emitNode.commentRange) || node;
+    }
+
+    /**
+     * Gets a custom text range to use when emitting source maps.
+     *
+     * @param node The node.
+     */
+    export function getSourceMapRange(node: Node) {
+        const emitNode = node.emitNode;
+        return (emitNode && emitNode.sourceMapRange) || node;
+    }
+
+    /**
+     * Gets the TextRange to use for source maps for a token of a node.
+     *
+     * @param node The node.
+     * @param token The token.
+     */
+    export function getTokenSourceMapRange(node: Node, token: SyntaxKind) {
+        const emitNode = node.emitNode;
+        const tokenSourceMapRanges = emitNode && emitNode.tokenSourceMapRanges;
+        return tokenSourceMapRanges && tokenSourceMapRanges[token];
+    }
+
     export function setTextRange<T extends TextRange>(node: T, location: TextRange): T {
         if (location) {
             node.pos = location.pos;
@@ -2706,7 +2839,7 @@ namespace ts {
         return undefined;
     }
 
-   /**
+    /**
      * Get the name of a target module from an import/export declaration as should be written in the emitted output.
      * The emitted output name can be different from the input if:
      *  1. The module has a /// <amd-module name="<new name>" />
diff --git a/src/compiler/sourcemap.ts b/src/compiler/sourcemap.ts
index 3517c54b407..d6e6501c598 100644
--- a/src/compiler/sourcemap.ts
+++ b/src/compiler/sourcemap.ts
@@ -38,10 +38,11 @@ namespace ts {
         /**
          * Emits a node with possible leading and trailing source maps.
          *
+         * @param emitContext The current emit context
          * @param node The node to emit.
          * @param emitCallback The callback used to emit the node.
          */
-        emitNodeWithSourceMap(node: Node, emitCallback: (node: Node) => void): void;
+        emitNodeWithSourceMap(emitContext: EmitContext, node: Node, emitCallback: (emitContext: EmitContext, node: Node) => void): void;
 
         /**
          * Emits a token of a node node with possible leading and trailing source maps.
@@ -313,9 +314,9 @@ namespace ts {
          * @param node The node to emit.
          * @param emitCallback The callback used to emit the node.
          */
-        function emitNodeWithSourceMap(node: Node, emitCallback: (node: Node) => void) {
+        function emitNodeWithSourceMap(emitContext: EmitContext, node: Node, emitCallback: (emitContext: EmitContext, node: Node) => void) {
             if (disabled) {
-                return emitCallback(node);
+                return emitCallback(emitContext, node);
             }
 
             if (node) {
@@ -331,11 +332,11 @@ namespace ts {
 
                 if (emitFlags & EmitFlags.NoNestedSourceMaps) {
                     disabled = true;
-                    emitCallback(node);
+                    emitCallback(emitContext, node);
                     disabled = false;
                 }
                 else {
-                    emitCallback(node);
+                    emitCallback(emitContext, node);
                 }
 
                 if (node.kind !== SyntaxKind.NotEmittedStatement
diff --git a/src/compiler/transformer.ts b/src/compiler/transformer.ts
index 5695bea7ae9..92407af2bb9 100644
--- a/src/compiler/transformer.ts
+++ b/src/compiler/transformer.ts
@@ -28,29 +28,25 @@ namespace ts {
         /**
          * Gets the transformed source files.
          */
-        getSourceFiles(): SourceFile[];
+        transformed: SourceFile[];
 
         /**
          * Emits the substitute for a node, if one is available; otherwise, emits the node.
          *
+         * @param emitContext The current emit context.
          * @param node The node to substitute.
-         * @param isExpression A value indicating whether the node is in an expression context.
          * @param emitCallback A callback used to emit the node or its substitute.
          */
-        emitNodeWithSubstitution(node: Node, isExpression: boolean, emitCallback: (node: Node) => void): void;
+        emitNodeWithSubstitution(emitContext: EmitContext, node: Node, emitCallback: (emitContext: EmitContext, node: Node) => void): void;
 
         /**
          * Emits a node with possible notification.
          *
+         * @param emitContext The current emit context.
          * @param node The node to emit.
          * @param emitCallback A callback used to emit the node.
          */
-        emitNodeWithNotification(node: Node, emitCallback: (node: Node) => void): void;
-
-        /**
-         * Reset transient transformation properties on parse tree nodes.
-         */
-        dispose(): void;
+        emitNodeWithNotification(emitContext: EmitContext, node: Node, emitCallback: (emitContext: EmitContext, node: Node) => void): void;
     }
 
     export interface TransformationContext extends LexicalEnvironment {
@@ -82,7 +78,7 @@ namespace ts {
          * Hook used by transformers to substitute expressions just before they
          * are emitted by the pretty printer.
          */
-        onSubstituteNode?: (node: Node, isExpression: boolean) => Node;
+        onSubstituteNode?: (emitContext: EmitContext, node: Node) => Node;
 
         /**
          * Enables before/after emit notifications in the pretty printer for the provided
@@ -100,7 +96,7 @@ namespace ts {
          * Hook used to allow transformers to capture state before or after
          * the printer emits a node.
          */
-        onEmitNode?: (node: Node, emit: (node: Node) => void) => void;
+        onEmitNode?: (emitContext: EmitContext, node: Node, emitCallback: (emitContext: EmitContext, node: Node) => void) => void;
     }
 
     /* @internal */
@@ -129,139 +125,6 @@ namespace ts {
         return transformers;
     }
 
-    /**
-     * Clears any EmitNode entries from parse-tree nodes.
-     * @param sourceFile A source file.
-     */
-    export function disposeEmitNodes(sourceFile: SourceFile) {
-        // During transformation we may need to annotate a parse tree node with transient
-        // transformation properties. As parse tree nodes live longer than transformation
-        // nodes, we need to make sure we reclaim any memory allocated for custom ranges
-        // from these nodes to ensure we do not hold onto entire subtrees just for position
-        // information. We also need to reset these nodes to a pre-transformation state
-        // for incremental parsing scenarios so that we do not impact later emit.
-        sourceFile = getSourceFileOfNode(getParseTreeNode(sourceFile));
-        const emitNode = sourceFile && sourceFile.emitNode;
-        const annotatedNodes = emitNode && emitNode.annotatedNodes;
-        if (annotatedNodes) {
-            for (const node of annotatedNodes) {
-                node.emitNode = undefined;
-            }
-        }
-    }
-
-    /**
-     * Associates a node with the current transformation, initializing
-     * various transient transformation properties.
-     *
-     * @param node The node.
-     */
-    function getOrCreateEmitNode(node: Node) {
-        if (!node.emitNode) {
-            if (isParseTreeNode(node)) {
-                // To avoid holding onto transformation artifacts, we keep track of any
-                // parse tree node we are annotating. This allows us to clean them up after
-                // all transformations have completed.
-                if (node.kind === SyntaxKind.SourceFile) {
-                    return node.emitNode = { annotatedNodes: [node] };
-                }
-
-                const sourceFile = getSourceFileOfNode(node);
-                getOrCreateEmitNode(sourceFile).annotatedNodes.push(node);
-            }
-
-            node.emitNode = {};
-        }
-
-        return node.emitNode;
-    }
-
-    /**
-     * Gets flags that control emit behavior of a node.
-     *
-     * @param node The node.
-     */
-    export function getEmitFlags(node: Node) {
-        const emitNode = node.emitNode;
-        return emitNode && emitNode.flags;
-    }
-
-    /**
-     * Sets flags that control emit behavior of a node.
-     *
-     * @param node The node.
-     * @param emitFlags The NodeEmitFlags for the node.
-     */
-    export function setEmitFlags<T extends Node>(node: T, emitFlags: EmitFlags) {
-        getOrCreateEmitNode(node).flags = emitFlags;
-        return node;
-    }
-
-    /**
-     * Sets a custom text range to use when emitting source maps.
-     *
-     * @param node The node.
-     * @param range The text range.
-     */
-    export function setSourceMapRange<T extends Node>(node: T, range: TextRange) {
-        getOrCreateEmitNode(node).sourceMapRange = range;
-        return node;
-    }
-
-    /**
-     * Sets the TextRange to use for source maps for a token of a node.
-     *
-     * @param node The node.
-     * @param token The token.
-     * @param range The text range.
-     */
-    export function setTokenSourceMapRange<T extends Node>(node: T, token: SyntaxKind, range: TextRange) {
-        const emitNode = getOrCreateEmitNode(node);
-        const tokenSourceMapRanges = emitNode.tokenSourceMapRanges || (emitNode.tokenSourceMapRanges = createMap<TextRange>());
-        tokenSourceMapRanges[token] = range;
-        return node;
-    }
-
-    /**
-     * Sets a custom text range to use when emitting comments.
-     */
-    export function setCommentRange<T extends Node>(node: T, range: TextRange) {
-        getOrCreateEmitNode(node).commentRange = range;
-        return node;
-    }
-
-    /**
-     * Gets a custom text range to use when emitting comments.
-     *
-     * @param node The node.
-     */
-    export function getCommentRange(node: Node) {
-        const emitNode = node.emitNode;
-        return (emitNode && emitNode.commentRange) || node;
-    }
-
-    /**
-     * Gets a custom text range to use when emitting source maps.
-     *
-     * @param node The node.
-     */
-    export function getSourceMapRange(node: Node) {
-        const emitNode = node.emitNode;
-        return (emitNode && emitNode.sourceMapRange) || node;
-    }
-
-    /**
-     * Gets the TextRange to use for source maps for a token of a node.
-     *
-     * @param node The node.
-     * @param token The token.
-     */
-    export function getTokenSourceMapRange(node: Node, token: SyntaxKind) {
-        const emitNode = node.emitNode;
-        const tokenSourceMapRanges = emitNode && emitNode.tokenSourceMapRanges;
-        return tokenSourceMapRanges && tokenSourceMapRanges[token];
-    }
-
     /**
      * Transforms an array of SourceFiles by passing them through each transformer.
      *
@@ -290,10 +153,10 @@ namespace ts {
             hoistFunctionDeclaration,
             startLexicalEnvironment,
             endLexicalEnvironment,
-            onSubstituteNode: (node, isExpression) => node,
+            onSubstituteNode: (emitContext, node) => node,
             enableSubstitution,
             isSubstitutionEnabled,
-            onEmitNode: (node, emitCallback) => emitCallback(node),
+            onEmitNode: (node, emitContext, emitCallback) => emitCallback(node, emitContext),
             enableEmitNotification,
             isEmitNotificationEnabled
         };
@@ -308,20 +171,9 @@ namespace ts {
         lexicalEnvironmentDisabled = true;
 
         return {
-            getSourceFiles: () => transformed,
+            transformed,
             emitNodeWithSubstitution,
-            emitNodeWithNotification,
-            dispose() {
-                // During transformation we may need to annotate a parse tree node with transient
-                // transformation properties. As parse tree nodes live longer than transformation
-                // nodes, we need to make sure we reclaim any memory allocated for custom ranges
-                // from these nodes to ensure we do not hold onto entire subtrees just for position
-                // information. We also need to reset these nodes to a pre-transformation state
-                // for incremental parsing scenarios so that we do not impact later emit.
-                for (const sourceFile of sourceFiles) {
-                    disposeEmitNodes(sourceFile);
-                }
-            }
+            emitNodeWithNotification
         };
 
         /**
@@ -355,21 +207,21 @@ namespace ts {
         /**
          * Emits a node with possible substitution.
          *
+         * @param emitContext The current emit context.
          * @param node The node to emit.
-         * @param isExpression Whether the node represents an expression.
          * @param emitCallback The callback used to emit the node or its substitute.
          */
-        function emitNodeWithSubstitution(node: Node, isExpression: boolean, emitCallback: (node: Node) => void) {
+        function emitNodeWithSubstitution(emitContext: EmitContext, node: Node, emitCallback: (emitContext: EmitContext, node: Node) => void) {
             if (node) {
                 if (isSubstitutionEnabled(node)) {
-                    const substitute = context.onSubstituteNode(node, isExpression);
+                    const substitute = context.onSubstituteNode(emitContext, node);
                     if (substitute && substitute !== node) {
-                        emitCallback(substitute);
+                        emitCallback(emitContext, substitute);
                         return;
                     }
                 }
 
-                emitCallback(node);
+                emitCallback(emitContext, node);
             }
         }
 
@@ -391,14 +243,18 @@ namespace ts {
 
         /**
          * Emits a node with possible emit notification.
+         *
+         * @param emitContext The current emit context.
+         * @param node The node to emit.
+         * @param emitCallback The callback used to emit the node.
          */
-        function emitNodeWithNotification(node: Node, emitCallback: (node: Node) => void) {
+        function emitNodeWithNotification(emitContext: EmitContext, node: Node, emitCallback: (emitContext: EmitContext, node: Node) => void) {
             if (node) {
                 if (isEmitNotificationEnabled(node)) {
-                    context.onEmitNode(node, emitCallback);
+                    context.onEmitNode(emitContext, node, emitCallback);
                 }
                 else {
-                    emitCallback(node);
+                    emitCallback(emitContext, node);
                 }
             }
         }
diff --git a/src/compiler/transformers/es6.ts b/src/compiler/transformers/es6.ts
index eda0d03c704..589478f1f6f 100644
--- a/src/compiler/transformers/es6.ts
+++ b/src/compiler/transformers/es6.ts
@@ -2852,7 +2852,7 @@ namespace ts {
          *
          * @param node The node to be printed.
          */
-        function onEmitNode(node: Node, emit: (node: Node) => void) {
+        function onEmitNode(emitContext: EmitContext, node: Node, emitCallback: (emitContext: EmitContext, node: Node) => void) {
             const savedUseCapturedThis = useCapturedThis;
 
             if (enabledSubstitutions & ES6SubstitutionFlags.CapturedThis && isFunctionLike(node)) {
@@ -2861,7 +2861,7 @@ namespace ts {
                 useCapturedThis = (getEmitFlags(node) & EmitFlags.CapturesThis) !== 0;
             }
 
-            previousOnEmitNode(node, emit);
+            previousOnEmitNode(emitContext, node, emitCallback);
 
             useCapturedThis = savedUseCapturedThis;
         }
@@ -2902,10 +2902,10 @@ namespace ts {
          * @param isExpression A value indicating whether the node is to be used in an expression
          *                     position.
          */
-        function onSubstituteNode(node: Node, isExpression: boolean) {
-            node = previousOnSubstituteNode(node, isExpression);
+        function onSubstituteNode(emitContext: EmitContext, node: Node) {
+            node = previousOnSubstituteNode(emitContext, node);
 
-            if (isExpression) {
+            if (emitContext === EmitContext.Expression) {
                 return substituteExpression(node);
             }
 
diff --git a/src/compiler/transformers/generators.ts b/src/compiler/transformers/generators.ts
index d6a30a81d61..58c18fdbc5d 100644
--- a/src/compiler/transformers/generators.ts
+++ b/src/compiler/transformers/generators.ts
@@ -1883,9 +1883,9 @@ namespace ts {
             return -1;
         }
 
-        function onSubstituteNode(node: Node, isExpression: boolean): Node {
-            node = previousOnSubstituteNode(node, isExpression);
-            if (isExpression) {
+        function onSubstituteNode(emitContext: EmitContext, node: Node): Node {
+            node = previousOnSubstituteNode(emitContext, node);
+            if (emitContext === EmitContext.Expression) {
                 return substituteExpression(<Expression>node);
             }
             return node;
diff --git a/src/compiler/transformers/module/module.ts b/src/compiler/transformers/module/module.ts
index 286ef967288..8bcf8f5fb25 100644
--- a/src/compiler/transformers/module/module.ts
+++ b/src/compiler/transformers/module/module.ts
@@ -822,14 +822,14 @@ namespace ts {
             return node.name ? getSynthesizedClone(node.name) : getGeneratedNameForNode(node);
         }
 
-        function onEmitNode(node: Node, emit: (node: Node) => void): void {
+        function onEmitNode(emitContext: EmitContext, node: Node, emitCallback: (emitContext: EmitContext, node: Node) => void): void {
             if (node.kind === SyntaxKind.SourceFile) {
                 bindingNameExportSpecifiersMap = bindingNameExportSpecifiersForFileMap[getOriginalNodeId(node)];
-                previousOnEmitNode(node, emit);
+                previousOnEmitNode(emitContext, node, emitCallback);
                 bindingNameExportSpecifiersMap = undefined;
             }
             else {
-                previousOnEmitNode(node, emit);
+                previousOnEmitNode(emitContext, node, emitCallback);
             }
         }
 
@@ -840,9 +840,9 @@ namespace ts {
          * @param isExpression A value indicating whether the node is to be used in an expression
          *                     position.
          */
-        function onSubstituteNode(node: Node, isExpression: boolean) {
-            node = previousOnSubstituteNode(node, isExpression);
-            if (isExpression) {
+        function onSubstituteNode(emitContext: EmitContext, node: Node) {
+            node = previousOnSubstituteNode(emitContext, node);
+            if (emitContext === EmitContext.Expression) {
                 return substituteExpression(<Expression>node);
             }
             else if (isShorthandPropertyAssignment(node)) {
diff --git a/src/compiler/transformers/module/system.ts b/src/compiler/transformers/module/system.ts
index 2a14f341272..7e5b36d239c 100644
--- a/src/compiler/transformers/module/system.ts
+++ b/src/compiler/transformers/module/system.ts
@@ -986,14 +986,14 @@ namespace ts {
         // Substitutions
         //
 
-        function onEmitNode(node: Node, emit: (node: Node) => void): void {
+        function onEmitNode(emitContext: EmitContext, node: Node, emitCallback: (emitContext: EmitContext, node: Node) => void): void {
             if (node.kind === SyntaxKind.SourceFile) {
                 exportFunctionForFile = exportFunctionForFileMap[getOriginalNodeId(node)];
-                previousOnEmitNode(node, emit);
+                previousOnEmitNode(emitContext, node, emitCallback);
                 exportFunctionForFile = undefined;
             }
             else {
-                previousOnEmitNode(node, emit);
+                previousOnEmitNode(emitContext, node, emitCallback);
             }
         }
 
@@ -1004,9 +1004,9 @@ namespace ts {
          * @param isExpression A value indicating whether the node is to be used in an expression
          *                     position.
          */
-        function onSubstituteNode(node: Node, isExpression: boolean) {
-            node = previousOnSubstituteNode(node, isExpression);
-            if (isExpression) {
+        function onSubstituteNode(emitContext: EmitContext, node: Node) {
+            node = previousOnSubstituteNode(emitContext, node);
+            if (emitContext === EmitContext.Expression) {
                 return substituteExpression(<Expression>node);
             }
 
diff --git a/src/compiler/transformers/ts.ts b/src/compiler/transformers/ts.ts
index e1892ff5bf4..225ab130d62 100644
--- a/src/compiler/transformers/ts.ts
+++ b/src/compiler/transformers/ts.ts
@@ -3231,7 +3231,7 @@ namespace ts {
          * @param node The node to emit.
          * @param emit A callback used to emit the node in the printer.
          */
-        function onEmitNode(node: Node, emit: (node: Node) => void): void {
+        function onEmitNode(emitContext: EmitContext, node: Node, emitCallback: (emitContext: EmitContext, node: Node) => void): void {
             const savedApplicableSubstitutions = applicableSubstitutions;
             const savedCurrentSuperContainer = currentSuperContainer;
             // If we need to support substitutions for `super` in an async method,
@@ -3248,7 +3248,7 @@ namespace ts {
                 applicableSubstitutions |= TypeScriptSubstitutionFlags.NonQualifiedEnumMembers;
             }
 
-            previousOnEmitNode(node, emit);
+            previousOnEmitNode(emitContext, node, emitCallback);
 
             applicableSubstitutions = savedApplicableSubstitutions;
             currentSuperContainer = savedCurrentSuperContainer;
@@ -3261,9 +3261,9 @@ namespace ts {
          * @param isExpression A value indicating whether the node is to be used in an expression
          *                     position.
          */
-        function onSubstituteNode(node: Node, isExpression: boolean) {
-            node = previousOnSubstituteNode(node, isExpression);
-            if (isExpression) {
+        function onSubstituteNode(emitContext: EmitContext, node: Node) {
+            node = previousOnSubstituteNode(emitContext, node);
+            if (emitContext === EmitContext.Expression) {
                 return substituteExpression(<Expression>node);
             }
             else if (isShorthandPropertyAssignment(node)) {
diff --git a/src/compiler/types.ts b/src/compiler/types.ts
index c18ebdd7200..74e7e741be8 100644
--- a/src/compiler/types.ts
+++ b/src/compiler/types.ts
@@ -3189,6 +3189,14 @@ namespace ts {
         CustomPrologue = 1 << 23,                // Treat the statement as if it were a prologue directive (NOTE: Prologue directives are *not* transformed).
     }
 
+    /* @internal */
+    export const enum EmitContext {
+        SourceFile,         // Emitting a SourceFile
+        Expression,         // Emitting an Expression
+        IdentifierName,     // Emitting an IdentifierName
+        Unspecified,        // Emitting an otherwise unspecified node
+    }
+
     /** Additional context provided to `visitEachChild` */
     /* @internal */
     export interface LexicalEnvironment {

From 21c10af13c1297e55a19c49d7dc12cef3d89ecd6 Mon Sep 17 00:00:00 2001
From: Ron Buckton <rbuckton@microsoft.com>
Date: Mon, 26 Sep 2016 17:53:46 -0700
Subject: [PATCH 35/47] Moved constant value emit to ts transform.

---
 src/compiler/emitter.ts                       | 46 +++------------
 src/compiler/factory.ts                       | 14 +++++
 src/compiler/transformers/ts.ts               | 58 ++++++++++++++-----
 src/compiler/types.ts                         |  2 +
 .../constEnumToStringWithComments.js          | 16 ++---
 5 files changed, 76 insertions(+), 60 deletions(-)

diff --git a/src/compiler/emitter.ts b/src/compiler/emitter.ts
index 03f785dc7de..6ad91069033 100644
--- a/src/compiler/emitter.ts
+++ b/src/compiler/emitter.ts
@@ -1143,10 +1143,6 @@ const _super = (function (geti, seti) {
         }
 
         function emitPropertyAccessExpression(node: PropertyAccessExpression) {
-            if (tryEmitConstantValue(node)) {
-                return;
-            }
-
             let indentBeforeDot = false;
             let indentAfterDot = false;
             if (!(getEmitFlags(node) & EmitFlags.NoIndentation)) {
@@ -1156,11 +1152,13 @@ const _super = (function (geti, seti) {
                 indentBeforeDot = needsIndentation(node, node.expression, dotToken);
                 indentAfterDot = needsIndentation(node, dotToken, node.name);
             }
-            const shouldEmitDotDot = !indentBeforeDot && needsDotDotForPropertyAccess(node.expression);
 
             emitExpression(node.expression);
             increaseIndentIf(indentBeforeDot);
+
+            const shouldEmitDotDot = !indentBeforeDot && needsDotDotForPropertyAccess(node.expression);
             write(shouldEmitDotDot ? ".." : ".");
+
             increaseIndentIf(indentAfterDot);
             emit(node.name);
             decreaseIndentIf(indentBeforeDot, indentAfterDot);
@@ -1176,17 +1174,15 @@ const _super = (function (geti, seti) {
             }
             else {
                 // check if constant enum value is integer
-                const constantValue = tryGetConstEnumValue(expression);
+                const constantValue = getConstantValue(expression);
                 // isFinite handles cases when constantValue is undefined
-                return isFinite(constantValue) && Math.floor(constantValue) === constantValue;
+                return isFinite(constantValue)
+                    && Math.floor(constantValue) === constantValue
+                    && compilerOptions.removeComments;
             }
         }
 
         function emitElementAccessExpression(node: ElementAccessExpression) {
-            if (tryEmitConstantValue(node)) {
-                return;
-            }
-
             emitExpression(node.expression);
             write("[");
             emitExpression(node.argumentExpression);
@@ -2260,24 +2256,6 @@ const _super = (function (geti, seti) {
             }
         }
 
-        // TODO(rbuckton): Move this into a transformer
-        function tryEmitConstantValue(node: PropertyAccessExpression | ElementAccessExpression): boolean {
-            const constantValue = tryGetConstEnumValue(node);
-            if (constantValue !== undefined) {
-                write(String(constantValue));
-                if (!compilerOptions.removeComments) {
-                    const propertyName = isPropertyAccessExpression(node)
-                        ? declarationNameToString(node.name)
-                        : getTextOfNode(node.argumentExpression);
-                    write(` /* ${propertyName} */`);
-                }
-
-                return true;
-            }
-
-            return false;
-        }
-
         function emitEmbeddedStatement(node: Statement) {
             if (isBlock(node)) {
                 write(" ");
@@ -2628,16 +2606,6 @@ const _super = (function (geti, seti) {
             return getLiteralText(node, currentSourceFile, languageVersion);
         }
 
-        function tryGetConstEnumValue(node: Node): number {
-            if (compilerOptions.isolatedModules) {
-                return undefined;
-            }
-
-            return isPropertyAccessExpression(node) || isElementAccessExpression(node)
-                ? resolver.getConstantValue(<PropertyAccessExpression | ElementAccessExpression>node)
-                : undefined;
-        }
-
         function isSingleLineEmptyBlock(block: Block) {
             return !block.multiLine
                 && block.statements.length === 0
diff --git a/src/compiler/factory.ts b/src/compiler/factory.ts
index b6fc2093288..75655d8cff8 100644
--- a/src/compiler/factory.ts
+++ b/src/compiler/factory.ts
@@ -2798,6 +2798,20 @@ namespace ts {
         return tokenSourceMapRanges && tokenSourceMapRanges[token];
     }
 
+    export function getConstantValue(node: Node) {
+        const emitNode = node.emitNode;
+        if (emitNode && emitNode.flags & EmitFlags.ConstantValue) {
+            return emitNode.constantValue;
+        }
+    }
+
+    export function setConstantValue(node: Node, value: number) {
+        const emitNode = getOrCreateEmitNode(node);
+        emitNode.constantValue = value;
+        emitNode.flags |= EmitFlags.ConstantValue;
+        return node;
+    }
+
     export function setTextRange<T extends TextRange>(node: T, location: TextRange): T {
         if (location) {
             node.pos = location.pos;
diff --git a/src/compiler/transformers/ts.ts b/src/compiler/transformers/ts.ts
index 225ab130d62..2a33ecc0e37 100644
--- a/src/compiler/transformers/ts.ts
+++ b/src/compiler/transformers/ts.ts
@@ -42,6 +42,10 @@ namespace ts {
         context.onEmitNode = onEmitNode;
         context.onSubstituteNode = onSubstituteNode;
 
+        // Enable substitution for property/element access to emit const enum values.
+        context.enableSubstitution(SyntaxKind.PropertyAccessExpression);
+        context.enableSubstitution(SyntaxKind.ElementAccessExpression);
+
         // These variables contain state that changes as we descend into the tree.
         let currentSourceFile: SourceFile;
         let currentNamespace: ModuleDeclaration;
@@ -3294,17 +3298,15 @@ namespace ts {
             switch (node.kind) {
                 case SyntaxKind.Identifier:
                     return substituteExpressionIdentifier(<Identifier>node);
-            }
-
-            if (enabledSubstitutions & TypeScriptSubstitutionFlags.AsyncMethodsWithSuper) {
-                switch (node.kind) {
-                    case SyntaxKind.CallExpression:
+                case SyntaxKind.PropertyAccessExpression:
+                    return substitutePropertyAccessExpression(<PropertyAccessExpression>node);
+                case SyntaxKind.ElementAccessExpression:
+                    return substituteElementAccessExpression(<ElementAccessExpression>node);
+                case SyntaxKind.CallExpression:
+                    if (enabledSubstitutions & TypeScriptSubstitutionFlags.AsyncMethodsWithSuper) {
                         return substituteCallExpression(<CallExpression>node);
-                    case SyntaxKind.PropertyAccessExpression:
-                        return substitutePropertyAccessExpression(<PropertyAccessExpression>node);
-                    case SyntaxKind.ElementAccessExpression:
-                        return substituteElementAccessExpression(<ElementAccessExpression>node);
-                }
+                    }
+                    break;
             }
 
             return node;
@@ -3381,7 +3383,7 @@ namespace ts {
         }
 
         function substitutePropertyAccessExpression(node: PropertyAccessExpression) {
-            if (node.expression.kind === SyntaxKind.SuperKeyword) {
+            if (enabledSubstitutions & TypeScriptSubstitutionFlags.AsyncMethodsWithSuper && node.expression.kind === SyntaxKind.SuperKeyword) {
                 const flags = getSuperContainerAsyncMethodFlags();
                 if (flags) {
                     return createSuperAccessInAsyncMethod(
@@ -3392,11 +3394,11 @@ namespace ts {
                 }
             }
 
-            return node;
+            return substituteConstantValue(node);
         }
 
         function substituteElementAccessExpression(node: ElementAccessExpression) {
-            if (node.expression.kind === SyntaxKind.SuperKeyword) {
+            if (enabledSubstitutions & TypeScriptSubstitutionFlags.AsyncMethodsWithSuper && node.expression.kind === SyntaxKind.SuperKeyword) {
                 const flags = getSuperContainerAsyncMethodFlags();
                 if (flags) {
                     return createSuperAccessInAsyncMethod(
@@ -3407,9 +3409,39 @@ namespace ts {
                 }
             }
 
+            return substituteConstantValue(node);
+        }
+
+        function substituteConstantValue(node: PropertyAccessExpression | ElementAccessExpression): LeftHandSideExpression {
+            const constantValue = tryGetConstEnumValue(node);
+            if (constantValue !== undefined) {
+                const substitute = createLiteral(constantValue);
+                setSourceMapRange(substitute, node);
+                setCommentRange(substitute, node);
+                if (!compilerOptions.removeComments) {
+                    const propertyName = isPropertyAccessExpression(node)
+                        ? declarationNameToString(node.name)
+                        : getTextOfNode(node.argumentExpression);
+                    substitute.trailingComment = ` ${propertyName} `;
+                }
+
+                setConstantValue(node, constantValue);
+                return substitute;
+            }
+
             return node;
         }
 
+        function tryGetConstEnumValue(node: Node): number {
+            if (compilerOptions.isolatedModules) {
+                return undefined;
+            }
+
+            return isPropertyAccessExpression(node) || isElementAccessExpression(node)
+                ? resolver.getConstantValue(<PropertyAccessExpression | ElementAccessExpression>node)
+                : undefined;
+        }
+
         function createSuperAccessInAsyncMethod(argumentExpression: Expression, flags: NodeCheckFlags, location: TextRange): LeftHandSideExpression {
             if (flags & NodeCheckFlags.AsyncMethodWithSuperBinding) {
                 return createPropertyAccess(
diff --git a/src/compiler/types.ts b/src/compiler/types.ts
index 74e7e741be8..e8a521ef3ff 100644
--- a/src/compiler/types.ts
+++ b/src/compiler/types.ts
@@ -3156,6 +3156,7 @@ namespace ts {
         sourceMapRange?: TextRange;
         tokenSourceMapRanges?: Map<TextRange>;
         annotatedNodes?: Node[];                // Tracks Parse-tree nodes with EmitNodes for eventual cleanup.
+        constantValue?: number;
     }
 
     /* @internal */
@@ -3187,6 +3188,7 @@ namespace ts {
         AsyncFunctionBody = 1 << 21,
         ReuseTempVariableScope = 1 << 22,        // Reuse the existing temp variable scope during emit.
         CustomPrologue = 1 << 23,                // Treat the statement as if it were a prologue directive (NOTE: Prologue directives are *not* transformed).
+        ConstantValue = 1 << 24,                 // The node was replaced with a constant value during substitution.
     }
 
     /* @internal */
diff --git a/tests/baselines/reference/constEnumToStringWithComments.js b/tests/baselines/reference/constEnumToStringWithComments.js
index c01e75cb923..f0fbc866385 100644
--- a/tests/baselines/reference/constEnumToStringWithComments.js
+++ b/tests/baselines/reference/constEnumToStringWithComments.js
@@ -23,15 +23,15 @@ let c1 = Foo["C"].toString();
 
 
 //// [constEnumToStringWithComments.js]
-var x0 = 100 /* X */..toString();
-var x1 = 100 /* "X" */..toString();
+var x0 = 100 /* X */.toString();
+var x1 = 100 /* "X" */.toString();
 var y0 = 0.5 /* Y */.toString();
 var y1 = 0.5 /* "Y" */.toString();
-var z0 = 2 /* Z */..toString();
-var z1 = 2 /* "Z" */..toString();
-var a0 = -1 /* A */..toString();
-var a1 = -1 /* "A" */..toString();
+var z0 = 2 /* Z */.toString();
+var z1 = 2 /* "Z" */.toString();
+var a0 = -1 /* A */.toString();
+var a1 = -1 /* "A" */.toString();
 var b0 = -1.5 /* B */.toString();
 var b1 = -1.5 /* "B" */.toString();
-var c0 = -1 /* C */..toString();
-var c1 = -1 /* "C" */..toString();
+var c0 = -1 /* C */.toString();
+var c1 = -1 /* "C" */.toString();

From 4a5830dd0c3e4d2d2e7cb350233d198ad7acd741 Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Tue, 27 Sep 2016 11:44:11 -0700
Subject: [PATCH 36/47] Remove usage of 'useCapturedThis'.

---
 src/compiler/transformers/es6.ts | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/src/compiler/transformers/es6.ts b/src/compiler/transformers/es6.ts
index 995b04c74da..2f529a09f9b 100644
--- a/src/compiler/transformers/es6.ts
+++ b/src/compiler/transformers/es6.ts
@@ -783,8 +783,6 @@ namespace ts {
         function addConstructor(statements: Statement[], node: ClassExpression | ClassDeclaration, extendsClauseElement: ExpressionWithTypeArguments): void {
             const constructor = getFirstConstructorWithBody(node);
             const hasSynthesizedSuper = hasSynthesizedDefaultSuperCall(constructor, extendsClauseElement !== undefined);
-            const savedUseCapturedThis = useCapturedThis;
-            useCapturedThis = true;
 
             const constructorFunction =
                 createFunctionDeclaration(
@@ -802,7 +800,6 @@ namespace ts {
             if (extendsClauseElement) {
                 setNodeEmitFlags(constructorFunction, NodeEmitFlags.CapturesThis);
             }
-            useCapturedThis = savedUseCapturedThis;
             statements.push(constructorFunction);
         }
 

From c668644e0b77e5843cdaed982a9d2d8340e1a5d8 Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Tue, 27 Sep 2016 14:09:26 -0700
Subject: [PATCH 37/47] Collapse 'super()' capture/returns into a single return
 statement for generated 'super()' calls.

---
 src/compiler/transformers/es6.ts | 32 +++++++++++++++++++++++++-------
 1 file changed, 25 insertions(+), 7 deletions(-)

diff --git a/src/compiler/transformers/es6.ts b/src/compiler/transformers/es6.ts
index 2f529a09f9b..ed5659e8a3f 100644
--- a/src/compiler/transformers/es6.ts
+++ b/src/compiler/transformers/es6.ts
@@ -837,7 +837,7 @@ namespace ts {
             startLexicalEnvironment();
 
             let statementOffset = -1;
-            let thisCaptureStatus = SuperCaptureResult.NoReplacement;
+            let superCaptureStatus = SuperCaptureResult.NoReplacement;
             if (hasSynthesizedSuper) {
                 // If a super call has already been synthesized,
                 // we're going to assume that we should just transform everything after that.
@@ -854,13 +854,17 @@ namespace ts {
                 addRestParameterIfNeeded(statements, constructor, hasSynthesizedSuper);
                 Debug.assert(statementOffset >= 0, "statementOffset not initialized correctly!");
 
-                thisCaptureStatus = declareOrCaptureOrReturnThisForConstructorIfNeeded(statements, constructor, !!extendsClauseElement, statementOffset);
-                if (thisCaptureStatus === SuperCaptureResult.ReplaceSuperCapture || thisCaptureStatus === SuperCaptureResult.ReplaceWithReturn) {
-                    statementOffset++;
-                }
+                superCaptureStatus = declareOrCaptureOrReturnThisForConstructorIfNeeded(statements, constructor, !!extendsClauseElement, statementOffset);
             }
 
-            addDefaultSuperCallIfNeeded(statements, constructor, extendsClauseElement, hasSynthesizedSuper);
+            if (superCaptureStatus === SuperCaptureResult.NoReplacement) {
+                superCaptureStatus = addDefaultSuperCallIfNeeded(statements, constructor, extendsClauseElement, hasSynthesizedSuper);
+            }
+
+            // The last statement expression was replaced. Skip it.
+            if (superCaptureStatus === SuperCaptureResult.ReplaceSuperCapture || superCaptureStatus === SuperCaptureResult.ReplaceWithReturn) {
+                statementOffset++;
+            }
 
             if (constructor) {
                 const body = saveStateAndInvoke(constructor, makeTransformerForConstructorBodyAtOffset(statementOffset));
@@ -870,7 +874,7 @@ namespace ts {
             // Return `_this` unless we're sure enough that it would be pointless to add a return statement.
             // If there's a constructor that we can tell returns in enough places, then we *do not* want to add a return.
             if (extendsClauseElement
-                && thisCaptureStatus !== SuperCaptureResult.ReplaceWithReturn
+                && superCaptureStatus !== SuperCaptureResult.ReplaceWithReturn
                 && !(constructor && isSufficientlyCoveredByReturnStatements(constructor.body))) {
                 statements.push(
                     createReturn(
@@ -955,6 +959,16 @@ namespace ts {
                 );
                 const superReturnValueOrThis = createLogicalOr(superCall, actualThis);
 
+                if (!constructor) {
+                    // We must be here because the user didn't write a constructor
+                    // but we needed to call 'super()' anyway - but if that's the case,
+                    // we can just immediately return the result of a 'super()' call.
+                    statements.push(createReturn(superReturnValueOrThis));
+                    return SuperCaptureResult.ReplaceWithReturn;
+                }
+
+                // The constructor was generated for some reason.
+                // Create a captured '_this' variable.
                 statements.push(
                     createVariableStatement(
                         /*modifiers*/ undefined,
@@ -969,7 +983,11 @@ namespace ts {
                 );
 
                 enableSubstitutionsForCapturedThis();
+
+                return SuperCaptureResult.ReplaceSuperCapture;
             }
+
+            return SuperCaptureResult.NoReplacement;
         }
 
         /**

From 1fbdb862027ed63828adb1c71bfc08a604bc1201 Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Tue, 27 Sep 2016 14:43:55 -0700
Subject: [PATCH 38/47] Accepted baselines.

---
 ...sClassHeritageListMemberTypeAnnotations.js |   3 +-
 ...accessibleTypeInTypeParameterConstraint.js |   3 +-
 .../reference/abstractClassInLocalScope.js    |   3 +-
 .../abstractClassInLocalScopeIsAbstract.js    |   3 +-
 .../reference/abstractPropertyNegative.js     |   3 +-
 .../accessors_spec_section-4.5_inference.js   |   3 +-
 .../reference/aliasUsageInAccessorsOfClass.js |   3 +-
 .../baselines/reference/aliasUsageInArray.js  |   3 +-
 .../aliasUsageInFunctionExpression.js         |   3 +-
 .../reference/aliasUsageInGenericFunction.js  |   3 +-
 .../reference/aliasUsageInIndexerOfClass.js   |   3 +-
 .../reference/aliasUsageInObjectLiteral.js    |   3 +-
 .../reference/aliasUsageInOrExpression.js     |   3 +-
 ...aliasUsageInTypeArgumentOfExtendsClause.js |   3 +-
 .../reference/aliasUsageInVarAssignment.js    |   3 +-
 .../reference/ambiguousOverloadResolution.js  |   3 +-
 .../reference/apparentTypeSubtyping.js        |   6 +-
 .../reference/apparentTypeSupertype.js        |   3 +-
 .../reference/arrayAssignmentTest1.js         |   3 +-
 .../reference/arrayAssignmentTest2.js         |   3 +-
 .../reference/arrayBestCommonTypes.js         |   6 +-
 .../reference/arrayLiteralTypeInference.js    |   6 +-
 tests/baselines/reference/arrayLiterals.js    |   6 +-
 .../arrayLiteralsWithRecursiveGenerics.js     |   3 +-
 ...rayOfSubtypeIsAssignableToReadonlyArray.js |   6 +-
 .../assignmentCompatWithCallSignatures3.js    |   9 +-
 .../assignmentCompatWithCallSignatures4.js    |   9 +-
 .../assignmentCompatWithCallSignatures5.js    |   9 +-
 .../assignmentCompatWithCallSignatures6.js    |   9 +-
 ...ssignmentCompatWithConstructSignatures3.js |   9 +-
 ...ssignmentCompatWithConstructSignatures4.js |   9 +-
 ...ssignmentCompatWithConstructSignatures5.js |   9 +-
 ...ssignmentCompatWithConstructSignatures6.js |   9 +-
 .../assignmentCompatWithNumericIndexer.js     |   3 +-
 .../assignmentCompatWithNumericIndexer3.js    |   3 +-
 .../assignmentCompatWithObjectMembers4.js     |  12 +-
 ...nmentCompatWithObjectMembersOptionality.js |   6 +-
 ...mentCompatWithObjectMembersOptionality2.js |   6 +-
 .../assignmentCompatWithStringIndexer.js      |   6 +-
 .../reference/asyncImportedPromise_es5.js     |   3 +-
 .../reference/asyncMethodWithSuper_es5.js     |   3 +-
 .../reference/asyncQualifiedReturnType_es5.js |   3 +-
 .../reference/awaitClassExpression_es5.js     |   3 +-
 .../reference/baseIndexSignatureResolution.js |   3 +-
 .../reference/baseTypeOrderChecking.js        |   6 +-
 .../baseTypeWrappingInstantiationChain.js     |   6 +-
 .../bestCommonTypeOfConditionalExpressions.js |   6 +-
 ...bestCommonTypeOfConditionalExpressions2.js |   6 +-
 .../reference/bestCommonTypeOfTuple2.js       |   3 +-
 ...allSignatureAssignabilityInInheritance2.js |   9 +-
 ...allSignatureAssignabilityInInheritance3.js |   9 +-
 ...allSignatureAssignabilityInInheritance4.js |   9 +-
 ...allSignatureAssignabilityInInheritance5.js |   9 +-
 ...allSignatureAssignabilityInInheritance6.js |   9 +-
 tests/baselines/reference/castingTuple.js     |   6 +-
 .../baselines/reference/chainedAssignment3.js |   3 +-
 ...arameterConstrainedToOtherTypeParameter.js |   6 +-
 .../reference/circularImportAlias.js          |   3 +-
 .../circularTypeofWithFunctionModule.js       |   3 +-
 .../classAbstractConstructorAssignability.js  |   6 +-
 .../reference/classAbstractCrashedOnce.js     |   3 +-
 .../reference/classAbstractExtends.js         |  12 +-
 .../reference/classAbstractFactoryFunction.js |   3 +-
 .../reference/classAbstractGeneric.js         |  18 +--
 .../reference/classAbstractInAModule.js       |   3 +-
 .../reference/classAbstractInheritance.js     |  24 +--
 .../reference/classAbstractInstantiations1.js |   6 +-
 .../reference/classAbstractInstantiations2.js |  12 +-
 .../classAbstractOverrideWithAbstract.js      |  12 +-
 .../reference/classAbstractSuperCalls.js      |   9 +-
 .../classAbstractUsingAbstractMethod1.js      |   6 +-
 .../classAbstractUsingAbstractMethods2.js     |  21 +--
 .../classConstructorAccessibility4.js         |   6 +-
 .../classConstructorAccessibility5.js         |   3 +-
 ...clarationMergedInModuleWithContinuation.js |   3 +-
 .../classDoesNotDependOnBaseTypes.js          |   3 +-
 tests/baselines/reference/classExpression2.js |   3 +-
 .../classExpressionExtendingAbstractClass.js  |   3 +-
 .../reference/classExtendingBuiltinType.js    |  30 ++--
 .../reference/classExtendingClass.js          |   6 +-
 .../reference/classExtendingClassLikeType.js  |   9 +-
 .../reference/classExtendingNonConstructor.js |  21 +--
 .../baselines/reference/classExtendingNull.js |   6 +-
 .../reference/classExtendingPrimitive.js      |  27 ++--
 .../reference/classExtendingPrimitive2.js     |   3 +-
 .../reference/classExtendingQualifiedName.js  |   3 +-
 .../reference/classExtendingQualifiedName2.js |   3 +-
 .../reference/classExtendsAcrossFiles.js      |   6 +-
 ...sMergedWithModuleNotReferingConstructor.js |   3 +-
 ...tendsClauseClassNotReferringConstructor.js |   3 +-
 .../reference/classExtendsEveryObjectType.js  |  18 +--
 .../reference/classExtendsEveryObjectType2.js |   6 +-
 .../reference/classExtendsInterface.js        |   6 +-
 .../classExtendsInterfaceInExpression.js      |   3 +-
 .../classExtendsInterfaceInModule.js          |   9 +-
 .../baselines/reference/classExtendsItself.js |   9 +-
 .../reference/classExtendsItselfIndirectly.js |  18 +--
 .../classExtendsItselfIndirectly2.js          |  18 +--
 .../classExtendsItselfIndirectly3.js          |  18 +--
 .../classExtendsMultipleBaseClasses.js        |   3 +-
 ...classExtendsShadowedConstructorFunction.js |   3 +-
 .../classExtendsValidConstructorFunction.js   |   3 +-
 .../classHeritageWithTrailingSeparator.js     |   3 +-
 .../reference/classImplementsClass2.js        |   3 +-
 .../reference/classImplementsClass3.js        |   3 +-
 .../reference/classImplementsClass4.js        |   3 +-
 .../reference/classImplementsClass5.js        |   3 +-
 .../reference/classImplementsClass6.js        |   3 +-
 tests/baselines/reference/classIndexer3.js    |   3 +-
 tests/baselines/reference/classInheritence.js |   6 +-
 .../reference/classIsSubtypeOfBaseType.js     |   6 +-
 tests/baselines/reference/classOrder2.js      |   3 +-
 tests/baselines/reference/classOrderBug.js    |   3 +-
 .../reference/classSideInheritance1.js        |   3 +-
 .../classWithBaseClassButNoConstructor.js     |  12 +-
 .../reference/classWithConstructors.js        |   6 +-
 .../reference/classWithProtectedProperty.js   |   3 +-
 .../reference/classWithStaticMembers.js       |   3 +-
 tests/baselines/reference/classdecl.js        |   9 +-
 .../reference/clodulesDerivedClasses.js       |   3 +-
 ...llisionSuperAndLocalFunctionInAccessors.js |   6 +-
 .../collisionSuperAndLocalFunctionInMethod.js |   6 +-
 .../collisionSuperAndLocalVarInAccessors.js   |   6 +-
 .../collisionSuperAndLocalVarInMethod.js      |   6 +-
 .../collisionSuperAndNameResolution.js        |   3 +-
 .../reference/collisionSuperAndParameter1.js  |   3 +-
 ...xpressionAndLocalVarWithSuperExperssion.js |   6 +-
 .../reference/commentsInheritance.js          |   3 +-
 .../comparisonOperatorWithIdenticalObjects.js |   6 +-
 ...ithNoRelationshipObjectsOnCallSignature.js |   3 +-
 ...lationshipObjectsOnConstructorSignature.js |   3 +-
 ...thNoRelationshipObjectsOnIndexSignature.js |   3 +-
 ...nshipObjectsOnInstantiatedCallSignature.js |   3 +-
 ...jectsOnInstantiatedConstructorSignature.js |   3 +-
 ...peratorWithSubtypeObjectOnCallSignature.js |   3 +-
 ...WithSubtypeObjectOnConstructorSignature.js |   3 +-
 ...eratorWithSubtypeObjectOnIndexSignature.js |   3 +-
 ...ubtypeObjectOnInstantiatedCallSignature.js |   3 +-
 ...bjectOnInstantiatedConstructorSignature.js |   3 +-
 ...isonOperatorWithSubtypeObjectOnProperty.js |   6 +-
 .../reference/complexClassRelationships.js    |   3 +-
 ...catedGenericRecursiveBaseClassReference.js |   3 +-
 .../reference/computedPropertyNames24_ES5.js  |   3 +-
 .../reference/computedPropertyNames25_ES5.js  |   3 +-
 .../reference/computedPropertyNames26_ES5.js  |   3 +-
 .../reference/computedPropertyNames27_ES5.js  |   3 +-
 .../reference/computedPropertyNames31_ES5.js  |   3 +-
 .../reference/computedPropertyNames43_ES5.js  |   3 +-
 .../reference/computedPropertyNames44_ES5.js  |   3 +-
 .../reference/computedPropertyNames45_ES5.js  |   3 +-
 .../conditionalOperatorWithIdenticalBCT.js    |   6 +-
 .../conditionalOperatorWithoutIdenticalBCT.js |   6 +-
 .../reference/constantOverloadFunction.js     |   9 +-
 .../constantOverloadFunctionNoSubtypeError.js |   9 +-
 ...nstraintCheckInGenericBaseTypeReference.js |   3 +-
 ...uctSignatureAssignabilityInInheritance2.js |   9 +-
 ...uctSignatureAssignabilityInInheritance3.js |   9 +-
 ...uctSignatureAssignabilityInInheritance4.js |   9 +-
 ...uctSignatureAssignabilityInInheritance5.js |   9 +-
 ...uctSignatureAssignabilityInInheritance6.js |   9 +-
 ...uctorFunctionTypeIsAssignableToBaseType.js |   6 +-
 .../constructorHasPrototypeProperty.js        |   6 +-
 ...constructorWithIncompleteTypeAnnotation.js |   3 +-
 .../contextualTypingArrayOfLambdas.js         |   6 +-
 ...contextualTypingOfConditionalExpression.js |   6 +-
 ...ontextualTypingOfConditionalExpression2.js |   6 +-
 ...urcePropertyIsRelatableToTargetProperty.js |   3 +-
 .../reference/declFileClassExtendsNull.js     |   3 +-
 .../declFileForFunctionTypeAsTypeParameter.js |   3 +-
 ...ileGenericClassWithGenericExtendedClass.js |   3 +-
 .../reference/declFileGenericType.js          |   3 +-
 ...lictingWithClassReferredByExtendsClause.js |   6 +-
 ...dsClauseThatHasItsContainerNameConflict.js |   3 +-
 .../declarationEmitExpressionInExtends.js     |   3 +-
 .../declarationEmitExpressionInExtends2.js    |   3 +-
 .../declarationEmitExpressionInExtends3.js    |  12 +-
 .../declarationEmitExpressionInExtends4.js    |   9 +-
 .../declarationEmitNameConflicts3.js          |   3 +-
 .../declarationEmitProtectedMembers.js        |   6 +-
 .../declarationEmitThisPredicates01.js        |   3 +-
 ...tionEmitThisPredicatesWithPrivateName01.js |   3 +-
 .../reference/declareDottedExtend.js          |   6 +-
 .../reference/decoratorOnClassMethod12.js     |   3 +-
 ...ClassFunctionOverridesBaseClassAccessor.js |   3 +-
 .../derivedClassIncludesInheritedMembers.js   |   6 +-
 ...idesIndexersWithAssignmentCompatibility.js |   6 +-
 .../derivedClassOverridesPrivates.js          |   6 +-
 .../derivedClassOverridesProtectedMembers2.js |   3 +-
 .../derivedClassOverridesProtectedMembers4.js |   6 +-
 .../derivedClassOverridesPublicMembers.js     |   3 +-
 .../derivedClassOverridesWithoutSubtype.js    |   6 +-
 .../reference/derivedClassTransitivity.js     |   6 +-
 .../reference/derivedClassTransitivity2.js    |   6 +-
 .../reference/derivedClassTransitivity3.js    |   6 +-
 .../reference/derivedClassTransitivity4.js    |   6 +-
 .../reference/derivedClassWithAny.js          |   6 +-
 ...ivateInstanceShadowingProtectedInstance.js |   3 +-
 ...hPrivateInstanceShadowingPublicInstance.js |   3 +-
 ...thPrivateStaticShadowingProtectedStatic.js |   3 +-
 ...sWithPrivateStaticShadowingPublicStatic.js |   3 +-
 tests/baselines/reference/derivedClasses.js   |   6 +-
 .../reference/derivedGenericClassWithAny.js   |   6 +-
 ...sesHiddenBaseCallViaSuperPropertyAccess.js |   3 +-
 .../derivedTypeDoesNotRequireExtendsClause.js |   3 +-
 .../reference/emitThisInSuperMethodCall.js    |   3 +-
 tests/baselines/reference/emptyModuleName.js  |   3 +-
 ...rorForwardReferenceForwadingConstructor.js |   3 +-
 .../reference/errorSuperPropertyAccess.js     |   3 +-
 .../reference/errorsInGenericTypeReference.js |   3 +-
 tests/baselines/reference/es6ClassTest2.js    |   3 +-
 tests/baselines/reference/es6ClassTest7.js    |   3 +-
 .../exportAssignmentOfGenericType1.js         |   3 +-
 .../exportDeclarationInInternalModule.js      |   3 +-
 tests/baselines/reference/extBaseClass1.js    |   9 +-
 tests/baselines/reference/extBaseClass2.js    |   6 +-
 .../extendAndImplementTheSameBaseType.js      |   3 +-
 .../extendAndImplementTheSameBaseType2.js     |   3 +-
 .../extendBaseClassBeforeItsDeclared.js       |   3 +-
 .../extendClassExpressionFromModule.js        |   3 +-
 .../extendConstructSignatureInInterface.js    |   3 +-
 .../reference/extendNonClassSymbol1.js        |   3 +-
 .../reference/extendNonClassSymbol2.js        |   3 +-
 ...xtendingClassFromAliasAndUsageInIndexer.js |   6 +-
 .../reference/extendsClauseAlreadySeen.js     |   3 +-
 .../reference/extendsClauseAlreadySeen2.js    |   3 +-
 tests/baselines/reference/fluentClasses.js    |   6 +-
 tests/baselines/reference/for-inStatements.js |   3 +-
 .../reference/for-inStatementsInvalid.js      |   3 +-
 .../forStatementsMultipleInvalidDecl.js       |   3 +-
 .../reference/functionImplementationErrors.js |   6 +-
 .../reference/functionImplementations.js      |   6 +-
 .../reference/functionSubtypingOfVarArgs.js   |   3 +-
 .../reference/functionSubtypingOfVarArgs2.js  |   3 +-
 .../reference/generatedContextualTyping.js    |   6 +-
 .../genericBaseClassLiteralProperty.js        |   3 +-
 .../genericBaseClassLiteralProperty2.js       |   3 +-
 ...allWithConstraintsTypeArgumentInference.js |   6 +-
 .../genericCallWithObjectTypeArgs2.js         |   6 +-
 ...icCallWithObjectTypeArgsAndConstraints2.js |   3 +-
 ...icCallWithObjectTypeArgsAndConstraints3.js |   6 +-
 .../genericCallbacksAndClassHierarchy.js      |   3 +-
 .../genericClassExpressionInFunction.js       |  18 +--
 ...sInheritsConstructorFromNonGenericClass.js |   6 +-
 .../reference/genericClassStaticMethod.js     |   3 +-
 tests/baselines/reference/genericClasses3.js  |   3 +-
 .../genericDerivedTypeWithSpecializedBase.js  |   3 +-
 .../genericDerivedTypeWithSpecializedBase2.js |   3 +-
 .../genericInheritedDefaultConstructors.js    |   3 +-
 .../reference/genericPrototypeProperty2.js    |   6 +-
 .../reference/genericPrototypeProperty3.js    |   6 +-
 ...ericRecursiveImplicitConstructorErrors2.js |   3 +-
 .../reference/genericTypeAssertions2.js       |   3 +-
 .../reference/genericTypeAssertions4.js       |   6 +-
 .../reference/genericTypeAssertions6.js       |   3 +-
 ...genericTypeReferenceWithoutTypeArgument.js |   6 +-
 ...enericTypeReferenceWithoutTypeArgument2.js |   6 +-
 .../genericWithIndexerOfTypeParameterType2.js |   6 +-
 .../reference/heterogeneousArrayLiterals.js   |   6 +-
 .../reference/ifDoWhileStatements.js          |   3 +-
 .../implementClausePrecedingExtends.js        |   3 +-
 ...gAnInterfaceExtendingClassWithPrivates2.js |  33 ++--
 ...AnInterfaceExtendingClassWithProtecteds.js |  12 +-
 .../baselines/reference/importAsBaseClass.js  |   3 +-
 tests/baselines/reference/importHelpers.js    |   6 +-
 tests/baselines/reference/importHelpersAmd.js |   3 +-
 .../importHelpersInIsolatedModules.js         |   6 +-
 .../reference/importHelpersNoHelpers.js       |   6 +-
 .../reference/importHelpersNoModule.js        |   6 +-
 .../reference/importHelpersOutFile.js         |   6 +-
 .../reference/importHelpersSystem.js          |   3 +-
 .../reference/importShadowsGlobalName.js      |   3 +-
 .../reference/importUsedInExtendsList1.js     |   3 +-
 .../reference/indexerConstraints2.js          |  12 +-
 .../reference/indirectSelfReference.js        |   6 +-
 .../reference/indirectSelfReferenceGeneric.js |   6 +-
 .../infinitelyExpandingTypesNonGenericBase.js |   3 +-
 .../inheritFromGenericTypeParameter.js        |   3 +-
 ...SameNamePrivatePropertiesFromSameOrigin.js |   6 +-
 tests/baselines/reference/inheritance.js      |  12 +-
 tests/baselines/reference/inheritance1.js     |  12 +-
 ...itanceGrandParentPrivateMemberCollision.js |   6 +-
 ...tPrivateMemberCollisionWithPublicMember.js |   6 +-
 ...tPublicMemberCollisionWithPrivateMember.js |   6 +-
 ...ritanceMemberAccessorOverridingAccessor.js |   3 +-
 ...heritanceMemberAccessorOverridingMethod.js |   3 +-
 ...ritanceMemberAccessorOverridingProperty.js |   3 +-
 ...inheritanceMemberFuncOverridingAccessor.js |   3 +-
 .../inheritanceMemberFuncOverridingMethod.js  |   3 +-
 ...inheritanceMemberFuncOverridingProperty.js |   3 +-
 ...ritanceMemberPropertyOverridingAccessor.js |   3 +-
 ...heritanceMemberPropertyOverridingMethod.js |   3 +-
 ...ritanceMemberPropertyOverridingProperty.js |   3 +-
 .../inheritanceOfGenericConstructorMethod1.js |   3 +-
 .../inheritanceOfGenericConstructorMethod2.js |   6 +-
 ...ritanceStaticAccessorOverridingAccessor.js |   3 +-
 ...heritanceStaticAccessorOverridingMethod.js |   3 +-
 ...ritanceStaticAccessorOverridingProperty.js |   3 +-
 ...inheritanceStaticFuncOverridingAccessor.js |   3 +-
 ...eStaticFuncOverridingAccessorOfFuncType.js |   3 +-
 .../inheritanceStaticFuncOverridingMethod.js  |   3 +-
 ...inheritanceStaticFuncOverridingProperty.js |   3 +-
 ...eStaticFuncOverridingPropertyOfFuncType.js |   3 +-
 ...taticFunctionOverridingInstanceProperty.js |   3 +-
 .../inheritanceStaticMembersCompatible.js     |   3 +-
 .../inheritanceStaticMembersIncompatible.js   |   3 +-
 ...ritanceStaticPropertyOverridingAccessor.js |   3 +-
 ...heritanceStaticPropertyOverridingMethod.js |   3 +-
 ...ritanceStaticPropertyOverridingProperty.js |   3 +-
 .../inheritedConstructorWithRestParams.js     |   3 +-
 .../inheritedConstructorWithRestParams2.js    |   6 +-
 .../inheritedModuleMembersForClodule.js       |   6 +-
 .../reference/instanceOfAssignability.js      |   6 +-
 ...nstancePropertiesInheritedIntoClassType.js |   6 +-
 .../reference/instanceSubtypeCheck2.js        |   3 +-
 ...nstanceofWithStructurallyIdenticalTypes.js |   6 +-
 .../instantiatedReturnTypeContravariance.js   |   3 +-
 .../reference/interfaceClassMerging.js        |   3 +-
 .../reference/interfaceClassMerging2.js       |   3 +-
 .../reference/interfaceExtendsClass1.js       |   9 +-
 .../interfaceExtendsClassWithPrivate1.js      |   3 +-
 .../reference/interfaceImplementation8.js     |  12 +-
 .../invalidModuleWithStatementsOfEveryKind.js |  18 +--
 .../invalidMultipleVariableDeclarations.js    |   3 +-
 .../reference/invalidReturnStatements.js      |   3 +-
 .../isolatedModulesImportExportElision.js     |   3 +-
 tests/baselines/reference/jsxViaImport.js     |   3 +-
 tests/baselines/reference/lambdaArgCrash.js   |   3 +-
 tests/baselines/reference/localTypes1.js      |   6 +-
 tests/baselines/reference/m7Bugs.js           |   3 +-
 .../reference/mergedDeclarations5.js          |   3 +-
 .../reference/mergedDeclarations6.js          |   3 +-
 .../mergedInheritedClassInterface.js          |   6 +-
 .../mergedInterfacesWithInheritedPrivates2.js |   6 +-
 .../mergedInterfacesWithInheritedPrivates3.js |   3 +-
 tests/baselines/reference/moduleAsBaseType.js |   3 +-
 .../moduleImportedForTypeArgumentPosition.js  |   3 +-
 .../moduleWithStatementsOfEveryKind.js        |  12 +-
 .../reference/multipleInheritance.js          |  18 +--
 .../mutuallyRecursiveGenericBaseTypes2.js     |   3 +-
 tests/baselines/reference/noEmitHelpers.js    |   3 +-
 .../noImplicitAnyMissingGetAccessor.js        |   3 +-
 .../noImplicitAnyMissingSetAccessor.js        |   3 +-
 ...enericClassExtendingGenericClassWithAny.js |   3 +-
 ...cIndexerConstrainsPropertyDeclarations2.js |   3 +-
 .../reference/numericIndexerConstraint3.js    |   3 +-
 .../reference/numericIndexerConstraint4.js    |   3 +-
 .../reference/numericIndexerTyping2.js        |   3 +-
 ...objectTypeHidingMembersOfExtendedObject.js |   3 +-
 ...objectTypesIdentityWithNumericIndexers1.js |   6 +-
 ...objectTypesIdentityWithNumericIndexers2.js |   9 +-
 ...objectTypesIdentityWithNumericIndexers3.js |   6 +-
 .../objectTypesIdentityWithPrivates.js        |   6 +-
 .../objectTypesIdentityWithPrivates2.js       |   3 +-
 .../objectTypesIdentityWithPrivates3.js       |   6 +-
 .../objectTypesIdentityWithStringIndexers.js  |   6 +-
 .../objectTypesIdentityWithStringIndexers2.js |   9 +-
 .../optionalConstructorArgInSuper.js          |   3 +-
 .../reference/optionalParamInOverride.js      |   3 +-
 .../baselines/reference/outModuleConcatAmd.js |   3 +-
 .../reference/outModuleConcatAmd.js.map       |   2 +-
 .../outModuleConcatAmd.sourcemap.txt          |  40 ++---
 .../reference/outModuleConcatSystem.js        |   3 +-
 .../reference/outModuleConcatSystem.js.map    |   2 +-
 .../outModuleConcatSystem.sourcemap.txt       |  40 ++---
 .../reference/outModuleTripleSlashRefs.js     |   3 +-
 .../reference/outModuleTripleSlashRefs.js.map |   2 +-
 .../outModuleTripleSlashRefs.sourcemap.txt    |  40 ++---
 tests/baselines/reference/overload1.js        |   6 +-
 .../overloadOnConstConstraintChecks1.js       |   9 +-
 .../overloadOnConstConstraintChecks2.js       |   6 +-
 .../overloadOnConstConstraintChecks3.js       |   6 +-
 .../overloadOnConstConstraintChecks4.js       |   6 +-
 .../overloadOnConstantsInvalidOverload1.js    |   9 +-
 .../baselines/reference/overloadResolution.js |   9 +-
 .../overloadResolutionClassConstructors.js    |   9 +-
 .../overloadResolutionConstructors.js         |   9 +-
 .../reference/overloadingOnConstants1.js      |   9 +-
 .../reference/overloadingOnConstants2.js      |   3 +-
 .../overridingPrivateStaticMembers.js         |   3 +-
 .../reference/parseErrorInHeritageClause1.js  |   3 +-
 tests/baselines/reference/parser509630.js     |   3 +-
 tests/baselines/reference/parserAstSpans1.js  |   3 +-
 .../reference/parserClassDeclaration1.js      |   3 +-
 .../reference/parserClassDeclaration3.js      |   3 +-
 .../reference/parserClassDeclaration4.js      |   3 +-
 .../reference/parserClassDeclaration5.js      |   3 +-
 .../reference/parserClassDeclaration6.js      |   3 +-
 ...rrorRecovery_ExtendsOrImplementsClause2.js |   3 +-
 ...rrorRecovery_ExtendsOrImplementsClause4.js |   3 +-
 ...rrorRecovery_ExtendsOrImplementsClause5.js |   3 +-
 .../parserGenericsInTypeContexts1.js          |   3 +-
 .../parserGenericsInTypeContexts2.js          |   3 +-
 tests/baselines/reference/primitiveMembers.js |   3 +-
 tests/baselines/reference/privacyClass.js     |  72 +++------
 .../privacyClassExtendsClauseDeclFile.js      |  69 +++------
 tests/baselines/reference/privacyGloClass.js  |  30 ++--
 .../reference/privateAccessInSubclass1.js     |   3 +-
 ...tedMembersAreNotAccessibleDestructuring.js |   3 +-
 .../privateStaticNotAccessibleInClodule2.js   |   3 +-
 .../amd/testGlo.js                            |  12 +-
 .../node/testGlo.js                           |  12 +-
 .../reference/project/prologueEmit/amd/out.js |   3 +-
 .../project/prologueEmit/node/out.js          |   3 +-
 .../amd/m'ain.js                              |   3 +-
 .../node/m'ain.js                             |   3 +-
 .../reference/propertiesAndIndexers.js        |   3 +-
 tests/baselines/reference/propertyAccess.js   |   3 +-
 ...tyAccessOnTypeParameterWithConstraints2.js |   3 +-
 ...tyAccessOnTypeParameterWithConstraints3.js |   3 +-
 ...tyAccessOnTypeParameterWithConstraints5.js |   3 +-
 ...sPropertyAccessibleWithinNestedSubclass.js |   6 +-
 ...PropertyAccessibleWithinNestedSubclass1.js |  12 +-
 ...edClassPropertyAccessibleWithinSubclass.js |   3 +-
 ...dClassPropertyAccessibleWithinSubclass2.js |  12 +-
 ...dClassPropertyAccessibleWithinSubclass3.js |   3 +-
 .../protectedInstanceMemberAccessibility.js   |   6 +-
 tests/baselines/reference/protectedMembers.js |  21 +--
 ...icClassPropertyAccessibleWithinSubclass.js |   9 +-
 ...cClassPropertyAccessibleWithinSubclass2.js |   6 +-
 ...solution-does-not-affect-class-heritage.js |   3 +-
 .../reference/recursiveBaseCheck3.js          |   6 +-
 .../reference/recursiveBaseCheck4.js          |   3 +-
 .../reference/recursiveBaseCheck6.js          |   3 +-
 .../recursiveBaseConstructorCreation1.js      |   3 +-
 ...ssInstantiationsWithDefaultConstructors.js |   3 +-
 .../reference/recursiveClassReferenceTest.js  |   3 +-
 .../recursiveClassReferenceTest.js.map        |   2 +-
 .../recursiveClassReferenceTest.sourcemap.txt | 144 +++++++++---------
 .../reference/recursiveComplicatedClasses.js  |   9 +-
 ...sivelySpecializedConstructorDeclaration.js |   3 +-
 .../reference/reexportClassDefinition.js      |   3 +-
 ...lassDeclarationWhenInBaseTypeResolution.js | 141 ++++++-----------
 tests/baselines/reference/returnStatements.js |   3 +-
 ...peCheckExtendedClassInsidePublicMethod2.js |   3 +-
 ...peCheckExtendedClassInsideStaticMethod1.js |   3 +-
 .../reference/shadowPrivateMembers.js         |   3 +-
 .../specializedInheritedConstructors1.js      |   3 +-
 .../specializedOverloadWithRestParameters.js  |   3 +-
 tests/baselines/reference/staticFactory1.js   |   3 +-
 .../staticMemberAccessOffDerivedType1.js      |   3 +-
 .../reference/strictModeReservedWord.js       |   3 +-
 ...trictModeReservedWordInClassDeclaration.js |   6 +-
 ...gIndexerConstrainsPropertyDeclarations2.js |   3 +-
 .../reference/subtypesOfTypeParameter.js      |   3 +-
 .../subtypesOfTypeParameterWithConstraints.js |  87 ++++-------
 ...subtypesOfTypeParameterWithConstraints4.js |  27 ++--
 ...OfTypeParameterWithRecursiveConstraints.js |  54 +++----
 .../reference/subtypingTransitivity.js        |   6 +-
 .../reference/subtypingWithCallSignatures2.js |   9 +-
 .../reference/subtypingWithCallSignatures3.js |   9 +-
 .../reference/subtypingWithCallSignatures4.js |   9 +-
 .../subtypingWithConstructSignatures2.js      |   9 +-
 .../subtypingWithConstructSignatures3.js      |   9 +-
 .../subtypingWithConstructSignatures4.js      |   9 +-
 .../subtypingWithConstructSignatures5.js      |   9 +-
 .../subtypingWithConstructSignatures6.js      |   9 +-
 .../reference/subtypingWithNumericIndexer.js  |  18 +--
 .../reference/subtypingWithNumericIndexer3.js |  21 +--
 .../reference/subtypingWithNumericIndexer4.js |   9 +-
 .../reference/subtypingWithObjectMembers.js   |  24 +--
 .../reference/subtypingWithObjectMembers4.js  |  12 +-
 ...subtypingWithObjectMembersAccessibility.js |  12 +-
 ...ubtypingWithObjectMembersAccessibility2.js |  21 +--
 .../reference/subtypingWithStringIndexer.js   |  18 +--
 .../reference/subtypingWithStringIndexer3.js  |  21 +--
 .../reference/subtypingWithStringIndexer4.js  |   9 +-
 tests/baselines/reference/super.js            |   6 +-
 tests/baselines/reference/super1.js           |  15 +-
 tests/baselines/reference/super2.js           |  12 +-
 tests/baselines/reference/superAccess.js      |   3 +-
 .../reference/superAccessInFatArrow1.js       |   3 +-
 .../reference/superCallInStaticMethod.js      |   3 +-
 .../superCallWithMissingBaseClass.js          |   3 +-
 .../baselines/reference/superInCatchBlock1.js |   3 +-
 .../reference/superInObjectLiterals_ES5.js    |   3 +-
 .../reference/superPropertyAccess.js          |   3 +-
 ...essInComputedPropertiesOfNestedType_ES5.js |   3 +-
 .../reference/superPropertyAccess_ES5.js      |   3 +-
 .../reference/superSymbolIndexedAccess5.js    |   3 +-
 .../reference/superSymbolIndexedAccess6.js    |   3 +-
 ...side-object-literal-getters-and-setters.js |   3 +-
 tests/baselines/reference/switchStatements.js |   3 +-
 .../reference/systemModuleWithSuperClass.js   |   3 +-
 .../reference/thisInInvalidContexts.js        |   3 +-
 .../thisInInvalidContextsExternalModule.js    |   3 +-
 .../reference/thisTypeInFunctions.js          |   9 +-
 .../reference/thisTypeInFunctionsNegative.js  |   6 +-
 .../reference/tsxExternalModuleEmit1.js       |   6 +-
 .../tsxStatelessFunctionComponents2.js        |   3 +-
 .../reference/tsxUnionTypeComponent1.js       |   6 +-
 tests/baselines/reference/typeAssertions.js   |   3 +-
 .../baselines/reference/typeGuardFunction.js  |   3 +-
 .../reference/typeGuardFunctionErrors.js      |   3 +-
 .../reference/typeGuardFunctionGenerics.js    |   3 +-
 .../reference/typeGuardFunctionOfFormThis.js  |  18 +--
 .../typeGuardFunctionOfFormThisErrors.js      |   6 +-
 .../reference/typeGuardOfFormInstanceOf.js    |   3 +-
 .../reference/typeGuardOfFormIsType.js        |   3 +-
 .../reference/typeGuardOfFormThisMember.js    |   3 +-
 .../typeGuardOfFormThisMemberErrors.js        |   3 +-
 tests/baselines/reference/typeMatch2.js       |   3 +-
 .../reference/typeParameterAsBaseClass.js     |   3 +-
 .../reference/typeParameterAsBaseType.js      |   6 +-
 .../reference/typeParameterExtendingUnion1.js |   6 +-
 .../reference/typeParameterExtendingUnion2.js |   6 +-
 .../baselines/reference/typeValueConflict1.js |   3 +-
 .../baselines/reference/typeValueConflict2.js |   6 +-
 tests/baselines/reference/typeofClass2.js     |   3 +-
 .../typesWithSpecializedCallSignatures.js     |   6 +-
 ...typesWithSpecializedConstructSignatures.js |   6 +-
 tests/baselines/reference/undeclaredBase.js   |   3 +-
 .../undefinedIsSubtypeOfEverything.js         |  66 +++-----
 .../baselines/reference/underscoreMapFirst.js |   3 +-
 .../reference/unionTypeEquivalence.js         |   3 +-
 .../reference/unionTypeFromArrayLiteral.js    |   6 +-
 .../reference/unionTypesAssignability.js      |   6 +-
 .../reference/unspecializedConstraints.js     |   3 +-
 ...untypedFunctionCallsWithTypeParameters1.js |   3 +-
 .../reference/unusedClassesinNamespace4.js    |   3 +-
 .../unusedIdentifiersConsolidated1.js         |   3 +-
 520 files changed, 1217 insertions(+), 2346 deletions(-)

diff --git a/tests/baselines/reference/ExportClassWithAccessibleTypesInTypeParameterConstraintsClassHeritageListMemberTypeAnnotations.js b/tests/baselines/reference/ExportClassWithAccessibleTypesInTypeParameterConstraintsClassHeritageListMemberTypeAnnotations.js
index de8e08843a2..ec0ed5494a4 100644
--- a/tests/baselines/reference/ExportClassWithAccessibleTypesInTypeParameterConstraintsClassHeritageListMemberTypeAnnotations.js
+++ b/tests/baselines/reference/ExportClassWithAccessibleTypesInTypeParameterConstraintsClassHeritageListMemberTypeAnnotations.js
@@ -38,8 +38,7 @@ var A;
     var Point3d = (function (_super) {
         __extends(Point3d, _super);
         function Point3d() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Point3d;
     }(Point));
diff --git a/tests/baselines/reference/ExportClassWithInaccessibleTypeInTypeParameterConstraint.js b/tests/baselines/reference/ExportClassWithInaccessibleTypeInTypeParameterConstraint.js
index 58c7bd4c3c1..bae9593fb98 100644
--- a/tests/baselines/reference/ExportClassWithInaccessibleTypeInTypeParameterConstraint.js
+++ b/tests/baselines/reference/ExportClassWithInaccessibleTypeInTypeParameterConstraint.js
@@ -41,8 +41,7 @@ var A;
     var Point3d = (function (_super) {
         __extends(Point3d, _super);
         function Point3d() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Point3d;
     }(Point));
diff --git a/tests/baselines/reference/abstractClassInLocalScope.js b/tests/baselines/reference/abstractClassInLocalScope.js
index 04407cfc08c..db5144be399 100644
--- a/tests/baselines/reference/abstractClassInLocalScope.js
+++ b/tests/baselines/reference/abstractClassInLocalScope.js
@@ -22,8 +22,7 @@ var __extends = (this && this.__extends) || function (d, b) {
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(A));
diff --git a/tests/baselines/reference/abstractClassInLocalScopeIsAbstract.js b/tests/baselines/reference/abstractClassInLocalScopeIsAbstract.js
index 09109c40675..1b3e11cfa32 100644
--- a/tests/baselines/reference/abstractClassInLocalScopeIsAbstract.js
+++ b/tests/baselines/reference/abstractClassInLocalScopeIsAbstract.js
@@ -22,8 +22,7 @@ var __extends = (this && this.__extends) || function (d, b) {
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(A));
diff --git a/tests/baselines/reference/abstractPropertyNegative.js b/tests/baselines/reference/abstractPropertyNegative.js
index 5a4c24fe233..bebf9026a0e 100644
--- a/tests/baselines/reference/abstractPropertyNegative.js
+++ b/tests/baselines/reference/abstractPropertyNegative.js
@@ -92,8 +92,7 @@ var WrongTypeAccessor = (function () {
 var WrongTypeAccessorImpl = (function (_super) {
     __extends(WrongTypeAccessorImpl, _super);
     function WrongTypeAccessorImpl() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Object.defineProperty(WrongTypeAccessorImpl.prototype, "num", {
         get: function () { return "nope, wrong"; },
diff --git a/tests/baselines/reference/accessors_spec_section-4.5_inference.js b/tests/baselines/reference/accessors_spec_section-4.5_inference.js
index 860d74f5204..dbaeec1f688 100644
--- a/tests/baselines/reference/accessors_spec_section-4.5_inference.js
+++ b/tests/baselines/reference/accessors_spec_section-4.5_inference.js
@@ -38,8 +38,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/aliasUsageInAccessorsOfClass.js b/tests/baselines/reference/aliasUsageInAccessorsOfClass.js
index d717da94d38..8b60ed8e76d 100644
--- a/tests/baselines/reference/aliasUsageInAccessorsOfClass.js
+++ b/tests/baselines/reference/aliasUsageInAccessorsOfClass.js
@@ -46,8 +46,7 @@ var Backbone = require("./aliasUsage1_backbone");
 var VisualizationModel = (function (_super) {
     __extends(VisualizationModel, _super);
     function VisualizationModel() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return VisualizationModel;
 }(Backbone.Model));
diff --git a/tests/baselines/reference/aliasUsageInArray.js b/tests/baselines/reference/aliasUsageInArray.js
index f08363776cc..bf573aa9abb 100644
--- a/tests/baselines/reference/aliasUsageInArray.js
+++ b/tests/baselines/reference/aliasUsageInArray.js
@@ -40,8 +40,7 @@ var Backbone = require("./aliasUsageInArray_backbone");
 var VisualizationModel = (function (_super) {
     __extends(VisualizationModel, _super);
     function VisualizationModel() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return VisualizationModel;
 }(Backbone.Model));
diff --git a/tests/baselines/reference/aliasUsageInFunctionExpression.js b/tests/baselines/reference/aliasUsageInFunctionExpression.js
index 06e3e266ee9..49bdd493aac 100644
--- a/tests/baselines/reference/aliasUsageInFunctionExpression.js
+++ b/tests/baselines/reference/aliasUsageInFunctionExpression.js
@@ -39,8 +39,7 @@ var Backbone = require("./aliasUsageInFunctionExpression_backbone");
 var VisualizationModel = (function (_super) {
     __extends(VisualizationModel, _super);
     function VisualizationModel() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return VisualizationModel;
 }(Backbone.Model));
diff --git a/tests/baselines/reference/aliasUsageInGenericFunction.js b/tests/baselines/reference/aliasUsageInGenericFunction.js
index 96121364837..dc3a8a88bab 100644
--- a/tests/baselines/reference/aliasUsageInGenericFunction.js
+++ b/tests/baselines/reference/aliasUsageInGenericFunction.js
@@ -43,8 +43,7 @@ var Backbone = require("./aliasUsageInGenericFunction_backbone");
 var VisualizationModel = (function (_super) {
     __extends(VisualizationModel, _super);
     function VisualizationModel() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return VisualizationModel;
 }(Backbone.Model));
diff --git a/tests/baselines/reference/aliasUsageInIndexerOfClass.js b/tests/baselines/reference/aliasUsageInIndexerOfClass.js
index bbfe2952594..cb7ad3027ca 100644
--- a/tests/baselines/reference/aliasUsageInIndexerOfClass.js
+++ b/tests/baselines/reference/aliasUsageInIndexerOfClass.js
@@ -45,8 +45,7 @@ var Backbone = require("./aliasUsageInIndexerOfClass_backbone");
 var VisualizationModel = (function (_super) {
     __extends(VisualizationModel, _super);
     function VisualizationModel() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return VisualizationModel;
 }(Backbone.Model));
diff --git a/tests/baselines/reference/aliasUsageInObjectLiteral.js b/tests/baselines/reference/aliasUsageInObjectLiteral.js
index 3b036f52a9d..81e3e621e85 100644
--- a/tests/baselines/reference/aliasUsageInObjectLiteral.js
+++ b/tests/baselines/reference/aliasUsageInObjectLiteral.js
@@ -40,8 +40,7 @@ var Backbone = require("./aliasUsageInObjectLiteral_backbone");
 var VisualizationModel = (function (_super) {
     __extends(VisualizationModel, _super);
     function VisualizationModel() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return VisualizationModel;
 }(Backbone.Model));
diff --git a/tests/baselines/reference/aliasUsageInOrExpression.js b/tests/baselines/reference/aliasUsageInOrExpression.js
index 4167294e5f2..4faa41dd034 100644
--- a/tests/baselines/reference/aliasUsageInOrExpression.js
+++ b/tests/baselines/reference/aliasUsageInOrExpression.js
@@ -43,8 +43,7 @@ var Backbone = require("./aliasUsageInOrExpression_backbone");
 var VisualizationModel = (function (_super) {
     __extends(VisualizationModel, _super);
     function VisualizationModel() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return VisualizationModel;
 }(Backbone.Model));
diff --git a/tests/baselines/reference/aliasUsageInTypeArgumentOfExtendsClause.js b/tests/baselines/reference/aliasUsageInTypeArgumentOfExtendsClause.js
index 91c6ca2c53f..2cf4aefab6c 100644
--- a/tests/baselines/reference/aliasUsageInTypeArgumentOfExtendsClause.js
+++ b/tests/baselines/reference/aliasUsageInTypeArgumentOfExtendsClause.js
@@ -43,8 +43,7 @@ var Backbone = require("./aliasUsageInTypeArgumentOfExtendsClause_backbone");
 var VisualizationModel = (function (_super) {
     __extends(VisualizationModel, _super);
     function VisualizationModel() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return VisualizationModel;
 }(Backbone.Model));
diff --git a/tests/baselines/reference/aliasUsageInVarAssignment.js b/tests/baselines/reference/aliasUsageInVarAssignment.js
index 0ba5cbbc8d0..80bb2dca20e 100644
--- a/tests/baselines/reference/aliasUsageInVarAssignment.js
+++ b/tests/baselines/reference/aliasUsageInVarAssignment.js
@@ -39,8 +39,7 @@ var Backbone = require("./aliasUsageInVarAssignment_backbone");
 var VisualizationModel = (function (_super) {
     __extends(VisualizationModel, _super);
     function VisualizationModel() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return VisualizationModel;
 }(Backbone.Model));
diff --git a/tests/baselines/reference/ambiguousOverloadResolution.js b/tests/baselines/reference/ambiguousOverloadResolution.js
index 27e6dd714ba..01002792921 100644
--- a/tests/baselines/reference/ambiguousOverloadResolution.js
+++ b/tests/baselines/reference/ambiguousOverloadResolution.js
@@ -22,8 +22,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/apparentTypeSubtyping.js b/tests/baselines/reference/apparentTypeSubtyping.js
index 914679c7de2..6ca9d343a72 100644
--- a/tests/baselines/reference/apparentTypeSubtyping.js
+++ b/tests/baselines/reference/apparentTypeSubtyping.js
@@ -38,8 +38,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
@@ -52,8 +51,7 @@ var Base2 = (function () {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Base2));
diff --git a/tests/baselines/reference/apparentTypeSupertype.js b/tests/baselines/reference/apparentTypeSupertype.js
index 01fdb92a24e..c6d3378872e 100644
--- a/tests/baselines/reference/apparentTypeSupertype.js
+++ b/tests/baselines/reference/apparentTypeSupertype.js
@@ -28,8 +28,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/arrayAssignmentTest1.js b/tests/baselines/reference/arrayAssignmentTest1.js
index 911df30a423..a887203cd5e 100644
--- a/tests/baselines/reference/arrayAssignmentTest1.js
+++ b/tests/baselines/reference/arrayAssignmentTest1.js
@@ -101,8 +101,7 @@ var C1 = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     C2.prototype.C2M1 = function () { return null; };
     return C2;
diff --git a/tests/baselines/reference/arrayAssignmentTest2.js b/tests/baselines/reference/arrayAssignmentTest2.js
index aff812247a2..d82dedff29d 100644
--- a/tests/baselines/reference/arrayAssignmentTest2.js
+++ b/tests/baselines/reference/arrayAssignmentTest2.js
@@ -75,8 +75,7 @@ var C1 = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     C2.prototype.C2M1 = function () { return null; };
     return C2;
diff --git a/tests/baselines/reference/arrayBestCommonTypes.js b/tests/baselines/reference/arrayBestCommonTypes.js
index 7df39836542..b7ddaa5d6da 100644
--- a/tests/baselines/reference/arrayBestCommonTypes.js
+++ b/tests/baselines/reference/arrayBestCommonTypes.js
@@ -128,8 +128,7 @@ var EmptyTypes;
     var derived = (function (_super) {
         __extends(derived, _super);
         function derived() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return derived;
     }(base));
@@ -188,8 +187,7 @@ var NonEmptyTypes;
     var derived = (function (_super) {
         __extends(derived, _super);
         function derived() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return derived;
     }(base));
diff --git a/tests/baselines/reference/arrayLiteralTypeInference.js b/tests/baselines/reference/arrayLiteralTypeInference.js
index 81155544cab..919d3a5e922 100644
--- a/tests/baselines/reference/arrayLiteralTypeInference.js
+++ b/tests/baselines/reference/arrayLiteralTypeInference.js
@@ -65,16 +65,14 @@ var Action = (function () {
 var ActionA = (function (_super) {
     __extends(ActionA, _super);
     function ActionA() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return ActionA;
 }(Action));
 var ActionB = (function (_super) {
     __extends(ActionB, _super);
     function ActionB() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return ActionB;
 }(Action));
diff --git a/tests/baselines/reference/arrayLiterals.js b/tests/baselines/reference/arrayLiterals.js
index 53066c70391..530cdedec73 100644
--- a/tests/baselines/reference/arrayLiterals.js
+++ b/tests/baselines/reference/arrayLiterals.js
@@ -70,8 +70,7 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived1;
 }(Base));
@@ -79,8 +78,7 @@ var Derived1 = (function (_super) {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/arrayLiteralsWithRecursiveGenerics.js b/tests/baselines/reference/arrayLiteralsWithRecursiveGenerics.js
index 3c5f4365053..c0f320ac1e5 100644
--- a/tests/baselines/reference/arrayLiteralsWithRecursiveGenerics.js
+++ b/tests/baselines/reference/arrayLiteralsWithRecursiveGenerics.js
@@ -39,8 +39,7 @@ var List = (function () {
 var DerivedList = (function (_super) {
     __extends(DerivedList, _super);
     function DerivedList() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return DerivedList;
 }(List));
diff --git a/tests/baselines/reference/arrayOfSubtypeIsAssignableToReadonlyArray.js b/tests/baselines/reference/arrayOfSubtypeIsAssignableToReadonlyArray.js
index aba7a7cbc8c..d1d75e8041c 100644
--- a/tests/baselines/reference/arrayOfSubtypeIsAssignableToReadonlyArray.js
+++ b/tests/baselines/reference/arrayOfSubtypeIsAssignableToReadonlyArray.js
@@ -33,16 +33,14 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(Array));
diff --git a/tests/baselines/reference/assignmentCompatWithCallSignatures3.js b/tests/baselines/reference/assignmentCompatWithCallSignatures3.js
index 80a9aa9cf14..c5a1f415437 100644
--- a/tests/baselines/reference/assignmentCompatWithCallSignatures3.js
+++ b/tests/baselines/reference/assignmentCompatWithCallSignatures3.js
@@ -114,24 +114,21 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/assignmentCompatWithCallSignatures4.js b/tests/baselines/reference/assignmentCompatWithCallSignatures4.js
index 5932aec049a..58faf663ea8 100644
--- a/tests/baselines/reference/assignmentCompatWithCallSignatures4.js
+++ b/tests/baselines/reference/assignmentCompatWithCallSignatures4.js
@@ -115,24 +115,21 @@ var Errors;
     var Derived = (function (_super) {
         __extends(Derived, _super);
         function Derived() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Derived;
     }(Base));
     var Derived2 = (function (_super) {
         __extends(Derived2, _super);
         function Derived2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Derived2;
     }(Derived));
     var OtherDerived = (function (_super) {
         __extends(OtherDerived, _super);
         function OtherDerived() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return OtherDerived;
     }(Base));
diff --git a/tests/baselines/reference/assignmentCompatWithCallSignatures5.js b/tests/baselines/reference/assignmentCompatWithCallSignatures5.js
index 7ea579d87ed..87506cad08f 100644
--- a/tests/baselines/reference/assignmentCompatWithCallSignatures5.js
+++ b/tests/baselines/reference/assignmentCompatWithCallSignatures5.js
@@ -80,24 +80,21 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/assignmentCompatWithCallSignatures6.js b/tests/baselines/reference/assignmentCompatWithCallSignatures6.js
index 0fb5867836c..2c05d5960b2 100644
--- a/tests/baselines/reference/assignmentCompatWithCallSignatures6.js
+++ b/tests/baselines/reference/assignmentCompatWithCallSignatures6.js
@@ -57,24 +57,21 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/assignmentCompatWithConstructSignatures3.js b/tests/baselines/reference/assignmentCompatWithConstructSignatures3.js
index b933425ffb0..76ad53e4e05 100644
--- a/tests/baselines/reference/assignmentCompatWithConstructSignatures3.js
+++ b/tests/baselines/reference/assignmentCompatWithConstructSignatures3.js
@@ -114,24 +114,21 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/assignmentCompatWithConstructSignatures4.js b/tests/baselines/reference/assignmentCompatWithConstructSignatures4.js
index e407c3acdb0..f516df153c6 100644
--- a/tests/baselines/reference/assignmentCompatWithConstructSignatures4.js
+++ b/tests/baselines/reference/assignmentCompatWithConstructSignatures4.js
@@ -115,24 +115,21 @@ var Errors;
     var Derived = (function (_super) {
         __extends(Derived, _super);
         function Derived() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Derived;
     }(Base));
     var Derived2 = (function (_super) {
         __extends(Derived2, _super);
         function Derived2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Derived2;
     }(Derived));
     var OtherDerived = (function (_super) {
         __extends(OtherDerived, _super);
         function OtherDerived() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return OtherDerived;
     }(Base));
diff --git a/tests/baselines/reference/assignmentCompatWithConstructSignatures5.js b/tests/baselines/reference/assignmentCompatWithConstructSignatures5.js
index 59c816dcc5c..ef7de7f011b 100644
--- a/tests/baselines/reference/assignmentCompatWithConstructSignatures5.js
+++ b/tests/baselines/reference/assignmentCompatWithConstructSignatures5.js
@@ -80,24 +80,21 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/assignmentCompatWithConstructSignatures6.js b/tests/baselines/reference/assignmentCompatWithConstructSignatures6.js
index b3b349ebc06..3d58ae707a5 100644
--- a/tests/baselines/reference/assignmentCompatWithConstructSignatures6.js
+++ b/tests/baselines/reference/assignmentCompatWithConstructSignatures6.js
@@ -57,24 +57,21 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/assignmentCompatWithNumericIndexer.js b/tests/baselines/reference/assignmentCompatWithNumericIndexer.js
index 6e14fb66ecd..37160506683 100644
--- a/tests/baselines/reference/assignmentCompatWithNumericIndexer.js
+++ b/tests/baselines/reference/assignmentCompatWithNumericIndexer.js
@@ -72,8 +72,7 @@ var Generics;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(A));
diff --git a/tests/baselines/reference/assignmentCompatWithNumericIndexer3.js b/tests/baselines/reference/assignmentCompatWithNumericIndexer3.js
index 3b32f327b07..2e6ecd72741 100644
--- a/tests/baselines/reference/assignmentCompatWithNumericIndexer3.js
+++ b/tests/baselines/reference/assignmentCompatWithNumericIndexer3.js
@@ -59,8 +59,7 @@ b = a; // ok
 var B2 = (function (_super) {
     __extends(B2, _super);
     function B2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B2;
 }(A));
diff --git a/tests/baselines/reference/assignmentCompatWithObjectMembers4.js b/tests/baselines/reference/assignmentCompatWithObjectMembers4.js
index ce80efc3c7a..2cc2510c8da 100644
--- a/tests/baselines/reference/assignmentCompatWithObjectMembers4.js
+++ b/tests/baselines/reference/assignmentCompatWithObjectMembers4.js
@@ -108,16 +108,14 @@ var OnlyDerived;
     var Derived = (function (_super) {
         __extends(Derived, _super);
         function Derived() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Derived;
     }(Base));
     var Derived2 = (function (_super) {
         __extends(Derived2, _super);
         function Derived2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Derived2;
     }(Base));
@@ -169,16 +167,14 @@ var WithBase;
     var Derived = (function (_super) {
         __extends(Derived, _super);
         function Derived() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Derived;
     }(Base));
     var Derived2 = (function (_super) {
         __extends(Derived2, _super);
         function Derived2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Derived2;
     }(Base));
diff --git a/tests/baselines/reference/assignmentCompatWithObjectMembersOptionality.js b/tests/baselines/reference/assignmentCompatWithObjectMembersOptionality.js
index d95eb43f0e5..3b12701b3d9 100644
--- a/tests/baselines/reference/assignmentCompatWithObjectMembersOptionality.js
+++ b/tests/baselines/reference/assignmentCompatWithObjectMembersOptionality.js
@@ -103,16 +103,14 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived));
diff --git a/tests/baselines/reference/assignmentCompatWithObjectMembersOptionality2.js b/tests/baselines/reference/assignmentCompatWithObjectMembersOptionality2.js
index f4c401979cf..f965d18e2ce 100644
--- a/tests/baselines/reference/assignmentCompatWithObjectMembersOptionality2.js
+++ b/tests/baselines/reference/assignmentCompatWithObjectMembersOptionality2.js
@@ -105,16 +105,14 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived));
diff --git a/tests/baselines/reference/assignmentCompatWithStringIndexer.js b/tests/baselines/reference/assignmentCompatWithStringIndexer.js
index 54839da4b5a..8d081c90794 100644
--- a/tests/baselines/reference/assignmentCompatWithStringIndexer.js
+++ b/tests/baselines/reference/assignmentCompatWithStringIndexer.js
@@ -82,8 +82,7 @@ var Generics;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(A));
@@ -94,8 +93,7 @@ var Generics;
     var B2 = (function (_super) {
         __extends(B2, _super);
         function B2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B2;
     }(A));
diff --git a/tests/baselines/reference/asyncImportedPromise_es5.js b/tests/baselines/reference/asyncImportedPromise_es5.js
index 396f380db3e..76ffbc833aa 100644
--- a/tests/baselines/reference/asyncImportedPromise_es5.js
+++ b/tests/baselines/reference/asyncImportedPromise_es5.js
@@ -19,8 +19,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var Task = (function (_super) {
     __extends(Task, _super);
     function Task() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Task;
 }(Promise));
diff --git a/tests/baselines/reference/asyncMethodWithSuper_es5.js b/tests/baselines/reference/asyncMethodWithSuper_es5.js
index 1bada582b03..9ceff6bab4e 100644
--- a/tests/baselines/reference/asyncMethodWithSuper_es5.js
+++ b/tests/baselines/reference/asyncMethodWithSuper_es5.js
@@ -61,8 +61,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     // async method with only call/get on 'super' does not require a binding
     B.prototype.simple = function () {
diff --git a/tests/baselines/reference/asyncQualifiedReturnType_es5.js b/tests/baselines/reference/asyncQualifiedReturnType_es5.js
index 0081a30d930..dd54f6ee833 100644
--- a/tests/baselines/reference/asyncQualifiedReturnType_es5.js
+++ b/tests/baselines/reference/asyncQualifiedReturnType_es5.js
@@ -13,8 +13,7 @@ var X;
     var MyPromise = (function (_super) {
         __extends(MyPromise, _super);
         function MyPromise() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return MyPromise;
     }(Promise));
diff --git a/tests/baselines/reference/awaitClassExpression_es5.js b/tests/baselines/reference/awaitClassExpression_es5.js
index f81b5800929..b207ba08f8d 100644
--- a/tests/baselines/reference/awaitClassExpression_es5.js
+++ b/tests/baselines/reference/awaitClassExpression_es5.js
@@ -17,8 +17,7 @@ function func() {
                     _a = function (_super) {
                         __extends(D, _super);
                         function D() {
-                            var _this = _super.apply(this, arguments) || this;
-                            return _this;
+                            return _super.apply(this, arguments) || this;
                         }
                         return D;
                     };
diff --git a/tests/baselines/reference/baseIndexSignatureResolution.js b/tests/baselines/reference/baseIndexSignatureResolution.js
index 6629ef35dda..7e922cf83b2 100644
--- a/tests/baselines/reference/baseIndexSignatureResolution.js
+++ b/tests/baselines/reference/baseIndexSignatureResolution.js
@@ -38,8 +38,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/baseTypeOrderChecking.js b/tests/baselines/reference/baseTypeOrderChecking.js
index 187a354553d..ec96b80a999 100644
--- a/tests/baselines/reference/baseTypeOrderChecking.js
+++ b/tests/baselines/reference/baseTypeOrderChecking.js
@@ -51,8 +51,7 @@ var Class1 = (function () {
 var Class2 = (function (_super) {
     __extends(Class2, _super);
     function Class2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Class2;
 }(Class1));
@@ -64,8 +63,7 @@ var Class3 = (function () {
 var Class4 = (function (_super) {
     __extends(Class4, _super);
     function Class4() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Class4;
 }(Class3));
diff --git a/tests/baselines/reference/baseTypeWrappingInstantiationChain.js b/tests/baselines/reference/baseTypeWrappingInstantiationChain.js
index bbf57046a97..5f8dcbd0e10 100644
--- a/tests/baselines/reference/baseTypeWrappingInstantiationChain.js
+++ b/tests/baselines/reference/baseTypeWrappingInstantiationChain.js
@@ -41,8 +41,7 @@ var CBaseBase = (function () {
 var CBase = (function (_super) {
     __extends(CBase, _super);
     function CBase() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return CBase;
 }(CBaseBase));
@@ -60,8 +59,7 @@ var Wrapper = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     C.prototype.works = function () {
         new CBaseBase(this);
diff --git a/tests/baselines/reference/bestCommonTypeOfConditionalExpressions.js b/tests/baselines/reference/bestCommonTypeOfConditionalExpressions.js
index a9e38f0520c..6d0f19dd37d 100644
--- a/tests/baselines/reference/bestCommonTypeOfConditionalExpressions.js
+++ b/tests/baselines/reference/bestCommonTypeOfConditionalExpressions.js
@@ -44,16 +44,14 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/bestCommonTypeOfConditionalExpressions2.js b/tests/baselines/reference/bestCommonTypeOfConditionalExpressions2.js
index 9af685812c2..2e2d0bcb1e2 100644
--- a/tests/baselines/reference/bestCommonTypeOfConditionalExpressions2.js
+++ b/tests/baselines/reference/bestCommonTypeOfConditionalExpressions2.js
@@ -40,16 +40,14 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/bestCommonTypeOfTuple2.js b/tests/baselines/reference/bestCommonTypeOfTuple2.js
index d71b6f17abf..928909f4c38 100644
--- a/tests/baselines/reference/bestCommonTypeOfTuple2.js
+++ b/tests/baselines/reference/bestCommonTypeOfTuple2.js
@@ -46,8 +46,7 @@ var E = (function () {
 var F = (function (_super) {
     __extends(F, _super);
     function F() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return F;
 }(C));
diff --git a/tests/baselines/reference/callSignatureAssignabilityInInheritance2.js b/tests/baselines/reference/callSignatureAssignabilityInInheritance2.js
index 4fd0dc2cefc..0ae7648c7f9 100644
--- a/tests/baselines/reference/callSignatureAssignabilityInInheritance2.js
+++ b/tests/baselines/reference/callSignatureAssignabilityInInheritance2.js
@@ -84,24 +84,21 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/callSignatureAssignabilityInInheritance3.js b/tests/baselines/reference/callSignatureAssignabilityInInheritance3.js
index 710725f145b..7a7791280ad 100644
--- a/tests/baselines/reference/callSignatureAssignabilityInInheritance3.js
+++ b/tests/baselines/reference/callSignatureAssignabilityInInheritance3.js
@@ -131,24 +131,21 @@ var Errors;
     var Derived = (function (_super) {
         __extends(Derived, _super);
         function Derived() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Derived;
     }(Base));
     var Derived2 = (function (_super) {
         __extends(Derived2, _super);
         function Derived2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Derived2;
     }(Derived));
     var OtherDerived = (function (_super) {
         __extends(OtherDerived, _super);
         function OtherDerived() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return OtherDerived;
     }(Base));
diff --git a/tests/baselines/reference/callSignatureAssignabilityInInheritance4.js b/tests/baselines/reference/callSignatureAssignabilityInInheritance4.js
index 154aee0693b..19d66ce8d46 100644
--- a/tests/baselines/reference/callSignatureAssignabilityInInheritance4.js
+++ b/tests/baselines/reference/callSignatureAssignabilityInInheritance4.js
@@ -64,24 +64,21 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/callSignatureAssignabilityInInheritance5.js b/tests/baselines/reference/callSignatureAssignabilityInInheritance5.js
index 7359d330cd6..1c53de5d26e 100644
--- a/tests/baselines/reference/callSignatureAssignabilityInInheritance5.js
+++ b/tests/baselines/reference/callSignatureAssignabilityInInheritance5.js
@@ -64,24 +64,21 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/callSignatureAssignabilityInInheritance6.js b/tests/baselines/reference/callSignatureAssignabilityInInheritance6.js
index 594d2dcafb7..c42e36389ca 100644
--- a/tests/baselines/reference/callSignatureAssignabilityInInheritance6.js
+++ b/tests/baselines/reference/callSignatureAssignabilityInInheritance6.js
@@ -67,24 +67,21 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/castingTuple.js b/tests/baselines/reference/castingTuple.js
index 426889df7de..f0178dcbbf0 100644
--- a/tests/baselines/reference/castingTuple.js
+++ b/tests/baselines/reference/castingTuple.js
@@ -59,8 +59,7 @@ var D = (function () {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return E;
 }(A));
@@ -68,8 +67,7 @@ var E = (function (_super) {
 var F = (function (_super) {
     __extends(F, _super);
     function F() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return F;
 }(A));
diff --git a/tests/baselines/reference/chainedAssignment3.js b/tests/baselines/reference/chainedAssignment3.js
index 71b345a311c..3857867043c 100644
--- a/tests/baselines/reference/chainedAssignment3.js
+++ b/tests/baselines/reference/chainedAssignment3.js
@@ -36,8 +36,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.js b/tests/baselines/reference/chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.js
index 7c428751b28..26d341e1f6a 100644
--- a/tests/baselines/reference/chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.js
+++ b/tests/baselines/reference/chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.js
@@ -42,16 +42,14 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(B));
diff --git a/tests/baselines/reference/circularImportAlias.js b/tests/baselines/reference/circularImportAlias.js
index 9d0e7648dcb..6fe5e604e57 100644
--- a/tests/baselines/reference/circularImportAlias.js
+++ b/tests/baselines/reference/circularImportAlias.js
@@ -32,8 +32,7 @@ var B;
     var D = (function (_super) {
         __extends(D, _super);
         function D() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D;
     }(B.a.C));
diff --git a/tests/baselines/reference/circularTypeofWithFunctionModule.js b/tests/baselines/reference/circularTypeofWithFunctionModule.js
index 811e86b21ca..78e9d3f34e7 100644
--- a/tests/baselines/reference/circularTypeofWithFunctionModule.js
+++ b/tests/baselines/reference/circularTypeofWithFunctionModule.js
@@ -32,8 +32,7 @@ var maker;
     var Bar = (function (_super) {
         __extends(Bar, _super);
         function Bar() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Bar;
     }(Foo));
diff --git a/tests/baselines/reference/classAbstractConstructorAssignability.js b/tests/baselines/reference/classAbstractConstructorAssignability.js
index 8738b43bb3f..35d9e75884f 100644
--- a/tests/baselines/reference/classAbstractConstructorAssignability.js
+++ b/tests/baselines/reference/classAbstractConstructorAssignability.js
@@ -28,16 +28,14 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(B));
diff --git a/tests/baselines/reference/classAbstractCrashedOnce.js b/tests/baselines/reference/classAbstractCrashedOnce.js
index 02d31377de8..fe23e60c94f 100644
--- a/tests/baselines/reference/classAbstractCrashedOnce.js
+++ b/tests/baselines/reference/classAbstractCrashedOnce.js
@@ -24,8 +24,7 @@ var foo = (function () {
 var bar = (function (_super) {
     __extends(bar, _super);
     function bar() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     bar.prototype.test = function () {
         this.
diff --git a/tests/baselines/reference/classAbstractExtends.js b/tests/baselines/reference/classAbstractExtends.js
index 8ac2cc9de3d..e899cb82d6d 100644
--- a/tests/baselines/reference/classAbstractExtends.js
+++ b/tests/baselines/reference/classAbstractExtends.js
@@ -31,32 +31,28 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(B));
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(B));
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     E.prototype.bar = function () { };
     return E;
diff --git a/tests/baselines/reference/classAbstractFactoryFunction.js b/tests/baselines/reference/classAbstractFactoryFunction.js
index 4f612e3d9c6..50e232a9fca 100644
--- a/tests/baselines/reference/classAbstractFactoryFunction.js
+++ b/tests/baselines/reference/classAbstractFactoryFunction.js
@@ -31,8 +31,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/classAbstractGeneric.js b/tests/baselines/reference/classAbstractGeneric.js
index b76117fddfc..96df8f5f19e 100644
--- a/tests/baselines/reference/classAbstractGeneric.js
+++ b/tests/baselines/reference/classAbstractGeneric.js
@@ -39,32 +39,28 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(A)); // error -- inherits abstract methods
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(A)); // error -- inherits abstract methods
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     E.prototype.foo = function () { return this.t; };
     return E;
@@ -72,8 +68,7 @@ var E = (function (_super) {
 var F = (function (_super) {
     __extends(F, _super);
     function F() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     F.prototype.bar = function (t) { };
     return F;
@@ -81,8 +76,7 @@ var F = (function (_super) {
 var G = (function (_super) {
     __extends(G, _super);
     function G() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     G.prototype.foo = function () { return this.t; };
     G.prototype.bar = function (t) { };
diff --git a/tests/baselines/reference/classAbstractInAModule.js b/tests/baselines/reference/classAbstractInAModule.js
index aa66ba540a8..c6a9e206bcc 100644
--- a/tests/baselines/reference/classAbstractInAModule.js
+++ b/tests/baselines/reference/classAbstractInAModule.js
@@ -24,8 +24,7 @@ var M;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(A));
diff --git a/tests/baselines/reference/classAbstractInheritance.js b/tests/baselines/reference/classAbstractInheritance.js
index 0bd5dab31a9..297a80dd99c 100644
--- a/tests/baselines/reference/classAbstractInheritance.js
+++ b/tests/baselines/reference/classAbstractInheritance.js
@@ -35,16 +35,14 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(A));
@@ -56,48 +54,42 @@ var AA = (function () {
 var BB = (function (_super) {
     __extends(BB, _super);
     function BB() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return BB;
 }(AA));
 var CC = (function (_super) {
     __extends(CC, _super);
     function CC() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return CC;
 }(AA));
 var DD = (function (_super) {
     __extends(DD, _super);
     function DD() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return DD;
 }(BB));
 var EE = (function (_super) {
     __extends(EE, _super);
     function EE() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return EE;
 }(BB));
 var FF = (function (_super) {
     __extends(FF, _super);
     function FF() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return FF;
 }(CC));
 var GG = (function (_super) {
     __extends(GG, _super);
     function GG() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return GG;
 }(CC));
diff --git a/tests/baselines/reference/classAbstractInstantiations1.js b/tests/baselines/reference/classAbstractInstantiations1.js
index aef8f58fab2..5abbb9c1baa 100644
--- a/tests/baselines/reference/classAbstractInstantiations1.js
+++ b/tests/baselines/reference/classAbstractInstantiations1.js
@@ -41,16 +41,14 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(B));
diff --git a/tests/baselines/reference/classAbstractInstantiations2.js b/tests/baselines/reference/classAbstractInstantiations2.js
index 2e6cd648dc0..dea4c744ae0 100644
--- a/tests/baselines/reference/classAbstractInstantiations2.js
+++ b/tests/baselines/reference/classAbstractInstantiations2.js
@@ -82,24 +82,21 @@ new x; // okay -- undefined behavior at runtime
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(B)); // error -- not declared abstract
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(B)); // okay
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     E.prototype.bar = function () { return 1; };
     return E;
@@ -107,8 +104,7 @@ var E = (function (_super) {
 var F = (function (_super) {
     __extends(F, _super);
     function F() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     F.prototype.bar = function () { return 2; };
     return F;
diff --git a/tests/baselines/reference/classAbstractOverrideWithAbstract.js b/tests/baselines/reference/classAbstractOverrideWithAbstract.js
index 5cb07934658..4ecebdf7b32 100644
--- a/tests/baselines/reference/classAbstractOverrideWithAbstract.js
+++ b/tests/baselines/reference/classAbstractOverrideWithAbstract.js
@@ -38,8 +38,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
@@ -52,8 +51,7 @@ var AA = (function () {
 var BB = (function (_super) {
     __extends(BB, _super);
     function BB() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     BB.prototype.bar = function () { };
     return BB;
@@ -61,16 +59,14 @@ var BB = (function (_super) {
 var CC = (function (_super) {
     __extends(CC, _super);
     function CC() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return CC;
 }(BB)); // error
 var DD = (function (_super) {
     __extends(DD, _super);
     function DD() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     DD.prototype.foo = function () { };
     return DD;
diff --git a/tests/baselines/reference/classAbstractSuperCalls.js b/tests/baselines/reference/classAbstractSuperCalls.js
index 44b15710c73..0197f48a429 100644
--- a/tests/baselines/reference/classAbstractSuperCalls.js
+++ b/tests/baselines/reference/classAbstractSuperCalls.js
@@ -42,8 +42,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     B.prototype.bar = function () { _super.prototype.foo.call(this); };
     B.prototype.baz = function () { return this.foo; };
@@ -52,8 +51,7 @@ var B = (function (_super) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     C.prototype.foo = function () { return 2; };
     C.prototype.qux = function () { return _super.prototype.foo.call(this) || _super.prototype.foo; }; // 2 errors, foo is abstract
@@ -70,8 +68,7 @@ var AA = (function () {
 var BB = (function (_super) {
     __extends(BB, _super);
     function BB() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return BB;
 }(AA));
diff --git a/tests/baselines/reference/classAbstractUsingAbstractMethod1.js b/tests/baselines/reference/classAbstractUsingAbstractMethod1.js
index ae6b08e4bca..74b5d62aaf5 100644
--- a/tests/baselines/reference/classAbstractUsingAbstractMethod1.js
+++ b/tests/baselines/reference/classAbstractUsingAbstractMethod1.js
@@ -31,8 +31,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     B.prototype.foo = function () { return 1; };
     return B;
@@ -40,8 +39,7 @@ var B = (function (_super) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/classAbstractUsingAbstractMethods2.js b/tests/baselines/reference/classAbstractUsingAbstractMethods2.js
index 9f43ee1a6b3..25cf1a307c7 100644
--- a/tests/baselines/reference/classAbstractUsingAbstractMethods2.js
+++ b/tests/baselines/reference/classAbstractUsingAbstractMethods2.js
@@ -41,24 +41,21 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(A));
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     D.prototype.foo = function () { };
     return D;
@@ -66,8 +63,7 @@ var D = (function (_super) {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     E.prototype.foo = function () { };
     return E;
@@ -80,24 +76,21 @@ var AA = (function () {
 var BB = (function (_super) {
     __extends(BB, _super);
     function BB() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return BB;
 }(AA));
 var CC = (function (_super) {
     __extends(CC, _super);
     function CC() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return CC;
 }(AA));
 var DD = (function (_super) {
     __extends(DD, _super);
     function DD() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     DD.prototype.foo = function () { };
     return DD;
diff --git a/tests/baselines/reference/classConstructorAccessibility4.js b/tests/baselines/reference/classConstructorAccessibility4.js
index dfbc70de115..4772ac68d11 100644
--- a/tests/baselines/reference/classConstructorAccessibility4.js
+++ b/tests/baselines/reference/classConstructorAccessibility4.js
@@ -51,8 +51,7 @@ var A = (function () {
         var C = (function (_super) {
             __extends(C, _super);
             function C() {
-                var _this = _super.apply(this, arguments) || this;
-                return _this;
+                return _super.apply(this, arguments) || this;
             }
             return C;
         }(A));
@@ -74,8 +73,7 @@ var D = (function () {
         var F = (function (_super) {
             __extends(F, _super);
             function F() {
-                var _this = _super.apply(this, arguments) || this;
-                return _this;
+                return _super.apply(this, arguments) || this;
             }
             return F;
         }(D));
diff --git a/tests/baselines/reference/classConstructorAccessibility5.js b/tests/baselines/reference/classConstructorAccessibility5.js
index b73ecb4a92b..d658349c2a5 100644
--- a/tests/baselines/reference/classConstructorAccessibility5.js
+++ b/tests/baselines/reference/classConstructorAccessibility5.js
@@ -25,8 +25,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived.make = function () { new Base(); }; // ok
     return Derived;
diff --git a/tests/baselines/reference/classDeclarationMergedInModuleWithContinuation.js b/tests/baselines/reference/classDeclarationMergedInModuleWithContinuation.js
index 83152355a13..c1ecad3a792 100644
--- a/tests/baselines/reference/classDeclarationMergedInModuleWithContinuation.js
+++ b/tests/baselines/reference/classDeclarationMergedInModuleWithContinuation.js
@@ -35,8 +35,7 @@ var M;
     var O = (function (_super) {
         __extends(O, _super);
         function O() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return O;
     }(M.N));
diff --git a/tests/baselines/reference/classDoesNotDependOnBaseTypes.js b/tests/baselines/reference/classDoesNotDependOnBaseTypes.js
index ef584afd6e9..076412e164d 100644
--- a/tests/baselines/reference/classDoesNotDependOnBaseTypes.js
+++ b/tests/baselines/reference/classDoesNotDependOnBaseTypes.js
@@ -31,8 +31,7 @@ var StringTreeCollectionBase = (function () {
 var StringTreeCollection = (function (_super) {
     __extends(StringTreeCollection, _super);
     function StringTreeCollection() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return StringTreeCollection;
 }(StringTreeCollectionBase));
diff --git a/tests/baselines/reference/classExpression2.js b/tests/baselines/reference/classExpression2.js
index f7405cfd38a..59b62c60cfe 100644
--- a/tests/baselines/reference/classExpression2.js
+++ b/tests/baselines/reference/classExpression2.js
@@ -16,8 +16,7 @@ var D = (function () {
 var v = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(D));
diff --git a/tests/baselines/reference/classExpressionExtendingAbstractClass.js b/tests/baselines/reference/classExpressionExtendingAbstractClass.js
index 8673e48d65f..7312ab6567d 100644
--- a/tests/baselines/reference/classExpressionExtendingAbstractClass.js
+++ b/tests/baselines/reference/classExpressionExtendingAbstractClass.js
@@ -22,8 +22,7 @@ var A = (function () {
 var C = (function (_super) {
     __extends(class_1, _super);
     function class_1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return class_1;
 }(A));
diff --git a/tests/baselines/reference/classExtendingBuiltinType.js b/tests/baselines/reference/classExtendingBuiltinType.js
index 2a01c1aa8b3..4c95e3008ea 100644
--- a/tests/baselines/reference/classExtendingBuiltinType.js
+++ b/tests/baselines/reference/classExtendingBuiltinType.js
@@ -20,80 +20,70 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C1 = (function (_super) {
     __extends(C1, _super);
     function C1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C1;
 }(Object));
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }(Function));
 var C3 = (function (_super) {
     __extends(C3, _super);
     function C3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C3;
 }(String));
 var C4 = (function (_super) {
     __extends(C4, _super);
     function C4() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C4;
 }(Boolean));
 var C5 = (function (_super) {
     __extends(C5, _super);
     function C5() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C5;
 }(Number));
 var C6 = (function (_super) {
     __extends(C6, _super);
     function C6() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C6;
 }(Date));
 var C7 = (function (_super) {
     __extends(C7, _super);
     function C7() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C7;
 }(RegExp));
 var C8 = (function (_super) {
     __extends(C8, _super);
     function C8() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C8;
 }(Error));
 var C9 = (function (_super) {
     __extends(C9, _super);
     function C9() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C9;
 }(Array));
 var C10 = (function (_super) {
     __extends(C10, _super);
     function C10() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C10;
 }(Array));
diff --git a/tests/baselines/reference/classExtendingClass.js b/tests/baselines/reference/classExtendingClass.js
index 4218bfbea98..91e3752980c 100644
--- a/tests/baselines/reference/classExtendingClass.js
+++ b/tests/baselines/reference/classExtendingClass.js
@@ -47,8 +47,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(C));
@@ -67,8 +66,7 @@ var C2 = (function () {
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D2;
 }(C2));
diff --git a/tests/baselines/reference/classExtendingClassLikeType.js b/tests/baselines/reference/classExtendingClassLikeType.js
index fdda53a381f..bfc10c23563 100644
--- a/tests/baselines/reference/classExtendingClassLikeType.js
+++ b/tests/baselines/reference/classExtendingClassLikeType.js
@@ -68,8 +68,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var D0 = (function (_super) {
     __extends(D0, _super);
     function D0() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D0;
 }(Base));
@@ -108,8 +107,7 @@ var D3 = (function (_super) {
 var D4 = (function (_super) {
     __extends(D4, _super);
     function D4() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D4;
 }(getBase()));
@@ -117,8 +115,7 @@ var D4 = (function (_super) {
 var D5 = (function (_super) {
     __extends(D5, _super);
     function D5() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D5;
 }(getBadBase()));
diff --git a/tests/baselines/reference/classExtendingNonConstructor.js b/tests/baselines/reference/classExtendingNonConstructor.js
index d33e6b4edef..574d5004486 100644
--- a/tests/baselines/reference/classExtendingNonConstructor.js
+++ b/tests/baselines/reference/classExtendingNonConstructor.js
@@ -27,56 +27,49 @@ function foo() {
 var C1 = (function (_super) {
     __extends(C1, _super);
     function C1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C1;
 }(undefined));
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }(true));
 var C3 = (function (_super) {
     __extends(C3, _super);
     function C3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C3;
 }(false));
 var C4 = (function (_super) {
     __extends(C4, _super);
     function C4() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C4;
 }(42));
 var C5 = (function (_super) {
     __extends(C5, _super);
     function C5() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C5;
 }("hello"));
 var C6 = (function (_super) {
     __extends(C6, _super);
     function C6() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C6;
 }(x));
 var C7 = (function (_super) {
     __extends(C7, _super);
     function C7() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C7;
 }(foo));
diff --git a/tests/baselines/reference/classExtendingNull.js b/tests/baselines/reference/classExtendingNull.js
index d6188aaf988..8d5d73329aa 100644
--- a/tests/baselines/reference/classExtendingNull.js
+++ b/tests/baselines/reference/classExtendingNull.js
@@ -12,16 +12,14 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C1 = (function (_super) {
     __extends(C1, _super);
     function C1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C1;
 }(null));
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }((null)));
diff --git a/tests/baselines/reference/classExtendingPrimitive.js b/tests/baselines/reference/classExtendingPrimitive.js
index c23683470d0..53cb45c2081 100644
--- a/tests/baselines/reference/classExtendingPrimitive.js
+++ b/tests/baselines/reference/classExtendingPrimitive.js
@@ -24,32 +24,28 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(number));
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }(string));
 var C3 = (function (_super) {
     __extends(C3, _super);
     function C3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C3;
 }(boolean));
 var C4 = (function (_super) {
     __extends(C4, _super);
     function C4() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C4;
 }(Void));
@@ -62,32 +58,28 @@ void {};
 var C5 = (function (_super) {
     __extends(C5, _super);
     function C5() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C5;
 }(Null));
 var C5a = (function (_super) {
     __extends(C5a, _super);
     function C5a() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C5a;
 }(null));
 var C6 = (function (_super) {
     __extends(C6, _super);
     function C6() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C6;
 }(undefined));
 var C7 = (function (_super) {
     __extends(C7, _super);
     function C7() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C7;
 }(Undefined));
@@ -98,8 +90,7 @@ var E;
 var C8 = (function (_super) {
     __extends(C8, _super);
     function C8() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C8;
 }(E));
diff --git a/tests/baselines/reference/classExtendingPrimitive2.js b/tests/baselines/reference/classExtendingPrimitive2.js
index 072dc8138c7..b32dc31a5b4 100644
--- a/tests/baselines/reference/classExtendingPrimitive2.js
+++ b/tests/baselines/reference/classExtendingPrimitive2.js
@@ -20,8 +20,7 @@ void {};
 var C5a = (function (_super) {
     __extends(C5a, _super);
     function C5a() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C5a;
 }(null));
diff --git a/tests/baselines/reference/classExtendingQualifiedName.js b/tests/baselines/reference/classExtendingQualifiedName.js
index b5cf4ae1382..fced8c2a373 100644
--- a/tests/baselines/reference/classExtendingQualifiedName.js
+++ b/tests/baselines/reference/classExtendingQualifiedName.js
@@ -23,8 +23,7 @@ var M;
     var D = (function (_super) {
         __extends(D, _super);
         function D() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D;
     }(M.C));
diff --git a/tests/baselines/reference/classExtendingQualifiedName2.js b/tests/baselines/reference/classExtendingQualifiedName2.js
index d1ee8b48b3a..c133ceb87dc 100644
--- a/tests/baselines/reference/classExtendingQualifiedName2.js
+++ b/tests/baselines/reference/classExtendingQualifiedName2.js
@@ -24,8 +24,7 @@ var M;
     var D = (function (_super) {
         __extends(D, _super);
         function D() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D;
     }(M.C));
diff --git a/tests/baselines/reference/classExtendsAcrossFiles.js b/tests/baselines/reference/classExtendsAcrossFiles.js
index 0dcf4103f49..5be0ab8f9c0 100644
--- a/tests/baselines/reference/classExtendsAcrossFiles.js
+++ b/tests/baselines/reference/classExtendsAcrossFiles.js
@@ -37,8 +37,7 @@ exports.b = {
         var B = (function (_super) {
             __extends(B, _super);
             function B() {
-                var _this = _super.apply(this, arguments) || this;
-                return _this;
+                return _super.apply(this, arguments) || this;
             }
             return B;
         }(A));
@@ -63,8 +62,7 @@ exports.a = {
         var B = (function (_super) {
             __extends(B, _super);
             function B() {
-                var _this = _super.apply(this, arguments) || this;
-                return _this;
+                return _super.apply(this, arguments) || this;
             }
             return B;
         }(A));
diff --git a/tests/baselines/reference/classExtendsClauseClassMergedWithModuleNotReferingConstructor.js b/tests/baselines/reference/classExtendsClauseClassMergedWithModuleNotReferingConstructor.js
index f1a695c0b2a..cc4870e837b 100644
--- a/tests/baselines/reference/classExtendsClauseClassMergedWithModuleNotReferingConstructor.js
+++ b/tests/baselines/reference/classExtendsClauseClassMergedWithModuleNotReferingConstructor.js
@@ -33,8 +33,7 @@ var Foo;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(A));
diff --git a/tests/baselines/reference/classExtendsClauseClassNotReferringConstructor.js b/tests/baselines/reference/classExtendsClauseClassNotReferringConstructor.js
index f754e140d37..6c3dc789445 100644
--- a/tests/baselines/reference/classExtendsClauseClassNotReferringConstructor.js
+++ b/tests/baselines/reference/classExtendsClauseClassNotReferringConstructor.js
@@ -23,8 +23,7 @@ var Foo;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(A));
diff --git a/tests/baselines/reference/classExtendsEveryObjectType.js b/tests/baselines/reference/classExtendsEveryObjectType.js
index 584b31b7e8e..a19f5d5cdd6 100644
--- a/tests/baselines/reference/classExtendsEveryObjectType.js
+++ b/tests/baselines/reference/classExtendsEveryObjectType.js
@@ -25,16 +25,14 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(I)); // error
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }({ foo: string })); // error
@@ -42,8 +40,7 @@ var x;
 var C3 = (function (_super) {
     __extends(C3, _super);
     function C3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C3;
 }(x)); // error
@@ -54,8 +51,7 @@ var M;
 var C4 = (function (_super) {
     __extends(C4, _super);
     function C4() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C4;
 }(M)); // error
@@ -63,16 +59,14 @@ function foo() { }
 var C5 = (function (_super) {
     __extends(C5, _super);
     function C5() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C5;
 }(foo)); // error
 var C6 = (function (_super) {
     __extends(C6, _super);
     function C6() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C6;
 }([])); // error
diff --git a/tests/baselines/reference/classExtendsEveryObjectType2.js b/tests/baselines/reference/classExtendsEveryObjectType2.js
index e01e90d512d..fbc364ca5da 100644
--- a/tests/baselines/reference/classExtendsEveryObjectType2.js
+++ b/tests/baselines/reference/classExtendsEveryObjectType2.js
@@ -12,16 +12,14 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }({ foo: string })); // error
 var C6 = (function (_super) {
     __extends(C6, _super);
     function C6() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C6;
 }([])); // error
diff --git a/tests/baselines/reference/classExtendsInterface.js b/tests/baselines/reference/classExtendsInterface.js
index 7047eaad658..b5946224317 100644
--- a/tests/baselines/reference/classExtendsInterface.js
+++ b/tests/baselines/reference/classExtendsInterface.js
@@ -17,8 +17,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var A = (function (_super) {
     __extends(A, _super);
     function A() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return A;
 }(Comparable));
@@ -30,8 +29,7 @@ var B = (function () {
 var A2 = (function (_super) {
     __extends(A2, _super);
     function A2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return A2;
 }(Comparable2));
diff --git a/tests/baselines/reference/classExtendsInterfaceInExpression.js b/tests/baselines/reference/classExtendsInterfaceInExpression.js
index 64d519d6952..9dcd8dd7279 100644
--- a/tests/baselines/reference/classExtendsInterfaceInExpression.js
+++ b/tests/baselines/reference/classExtendsInterfaceInExpression.js
@@ -20,8 +20,7 @@ function factory(a) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(factory(A)));
diff --git a/tests/baselines/reference/classExtendsInterfaceInModule.js b/tests/baselines/reference/classExtendsInterfaceInModule.js
index ced164bca10..9da8831a138 100644
--- a/tests/baselines/reference/classExtendsInterfaceInModule.js
+++ b/tests/baselines/reference/classExtendsInterfaceInModule.js
@@ -24,24 +24,21 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C1 = (function (_super) {
     __extends(C1, _super);
     function C1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C1;
 }(M.I1));
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }(M.I2));
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(Mod.Nested.I));
diff --git a/tests/baselines/reference/classExtendsItself.js b/tests/baselines/reference/classExtendsItself.js
index 654cd35c400..36f2263d671 100644
--- a/tests/baselines/reference/classExtendsItself.js
+++ b/tests/baselines/reference/classExtendsItself.js
@@ -14,24 +14,21 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(C)); // error
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(D)); // error
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return E;
 }(E)); // error
diff --git a/tests/baselines/reference/classExtendsItselfIndirectly.js b/tests/baselines/reference/classExtendsItselfIndirectly.js
index ae5852d91f9..0f3f48d2f2c 100644
--- a/tests/baselines/reference/classExtendsItselfIndirectly.js
+++ b/tests/baselines/reference/classExtendsItselfIndirectly.js
@@ -20,48 +20,42 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(E)); // error
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(C));
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return E;
 }(D));
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }(E2)); // error
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D2;
 }(C2));
 var E2 = (function (_super) {
     __extends(E2, _super);
     function E2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return E2;
 }(D2));
diff --git a/tests/baselines/reference/classExtendsItselfIndirectly2.js b/tests/baselines/reference/classExtendsItselfIndirectly2.js
index 63eeb5bc178..e215a07c357 100644
--- a/tests/baselines/reference/classExtendsItselfIndirectly2.js
+++ b/tests/baselines/reference/classExtendsItselfIndirectly2.js
@@ -31,8 +31,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(N.E)); // error
@@ -41,8 +40,7 @@ var M;
     var D = (function (_super) {
         __extends(D, _super);
         function D() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D;
     }(C));
@@ -53,8 +51,7 @@ var N;
     var E = (function (_super) {
         __extends(E, _super);
         function E() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return E;
     }(M.D));
@@ -65,8 +62,7 @@ var O;
     var C2 = (function (_super) {
         __extends(C2, _super);
         function C2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return C2;
     }(Q.E2)); // error
@@ -75,8 +71,7 @@ var O;
         var D2 = (function (_super) {
             __extends(D2, _super);
             function D2() {
-                var _this = _super.apply(this, arguments) || this;
-                return _this;
+                return _super.apply(this, arguments) || this;
             }
             return D2;
         }(C2));
@@ -87,8 +82,7 @@ var O;
         var E2 = (function (_super) {
             __extends(E2, _super);
             function E2() {
-                var _this = _super.apply(this, arguments) || this;
-                return _this;
+                return _super.apply(this, arguments) || this;
             }
             return E2;
         }(P.D2));
diff --git a/tests/baselines/reference/classExtendsItselfIndirectly3.js b/tests/baselines/reference/classExtendsItselfIndirectly3.js
index 4e67909f2d3..f8366d77e13 100644
--- a/tests/baselines/reference/classExtendsItselfIndirectly3.js
+++ b/tests/baselines/reference/classExtendsItselfIndirectly3.js
@@ -27,8 +27,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(E)); // error
@@ -41,8 +40,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(C));
@@ -55,8 +53,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return E;
 }(D));
@@ -69,8 +66,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }(E2)); // error
@@ -83,8 +79,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D2;
 }(C2));
@@ -97,8 +92,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var E2 = (function (_super) {
     __extends(E2, _super);
     function E2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return E2;
 }(D2));
diff --git a/tests/baselines/reference/classExtendsMultipleBaseClasses.js b/tests/baselines/reference/classExtendsMultipleBaseClasses.js
index a185f6cf40a..cd9c28ad283 100644
--- a/tests/baselines/reference/classExtendsMultipleBaseClasses.js
+++ b/tests/baselines/reference/classExtendsMultipleBaseClasses.js
@@ -22,8 +22,7 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/classExtendsShadowedConstructorFunction.js b/tests/baselines/reference/classExtendsShadowedConstructorFunction.js
index a7f4a4bb9d9..ddaadc2dc62 100644
--- a/tests/baselines/reference/classExtendsShadowedConstructorFunction.js
+++ b/tests/baselines/reference/classExtendsShadowedConstructorFunction.js
@@ -25,8 +25,7 @@ var M;
     var D = (function (_super) {
         __extends(D, _super);
         function D() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D;
     }(C));
diff --git a/tests/baselines/reference/classExtendsValidConstructorFunction.js b/tests/baselines/reference/classExtendsValidConstructorFunction.js
index 519074358cc..31bff6e430c 100644
--- a/tests/baselines/reference/classExtendsValidConstructorFunction.js
+++ b/tests/baselines/reference/classExtendsValidConstructorFunction.js
@@ -16,8 +16,7 @@ var x = new foo(); // can be used as a constructor function
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(foo)); // error, cannot extend it though
diff --git a/tests/baselines/reference/classHeritageWithTrailingSeparator.js b/tests/baselines/reference/classHeritageWithTrailingSeparator.js
index d3134a97ccd..12265f569bd 100644
--- a/tests/baselines/reference/classHeritageWithTrailingSeparator.js
+++ b/tests/baselines/reference/classHeritageWithTrailingSeparator.js
@@ -17,8 +17,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/classImplementsClass2.js b/tests/baselines/reference/classImplementsClass2.js
index d525fb8a6ad..5e3eae46543 100644
--- a/tests/baselines/reference/classImplementsClass2.js
+++ b/tests/baselines/reference/classImplementsClass2.js
@@ -33,8 +33,7 @@ var C = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     C2.prototype.foo = function () {
         return 1;
diff --git a/tests/baselines/reference/classImplementsClass3.js b/tests/baselines/reference/classImplementsClass3.js
index 3257e51b5b8..5fd003e93b9 100644
--- a/tests/baselines/reference/classImplementsClass3.js
+++ b/tests/baselines/reference/classImplementsClass3.js
@@ -37,8 +37,7 @@ var C = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }(A));
diff --git a/tests/baselines/reference/classImplementsClass4.js b/tests/baselines/reference/classImplementsClass4.js
index f0b8698c64d..477288972df 100644
--- a/tests/baselines/reference/classImplementsClass4.js
+++ b/tests/baselines/reference/classImplementsClass4.js
@@ -40,8 +40,7 @@ var C = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }(A));
diff --git a/tests/baselines/reference/classImplementsClass5.js b/tests/baselines/reference/classImplementsClass5.js
index bf5d0141a19..0ec258ab77b 100644
--- a/tests/baselines/reference/classImplementsClass5.js
+++ b/tests/baselines/reference/classImplementsClass5.js
@@ -42,8 +42,7 @@ var C = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }(A));
diff --git a/tests/baselines/reference/classImplementsClass6.js b/tests/baselines/reference/classImplementsClass6.js
index f1929cdc798..0771c56415c 100644
--- a/tests/baselines/reference/classImplementsClass6.js
+++ b/tests/baselines/reference/classImplementsClass6.js
@@ -47,8 +47,7 @@ var C = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }(A));
diff --git a/tests/baselines/reference/classIndexer3.js b/tests/baselines/reference/classIndexer3.js
index ab825abcd31..2e55c894645 100644
--- a/tests/baselines/reference/classIndexer3.js
+++ b/tests/baselines/reference/classIndexer3.js
@@ -24,8 +24,7 @@ var C123 = (function () {
 var D123 = (function (_super) {
     __extends(D123, _super);
     function D123() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D123;
 }(C123));
diff --git a/tests/baselines/reference/classInheritence.js b/tests/baselines/reference/classInheritence.js
index 11b0c5e3ae2..f68d76fad47 100644
--- a/tests/baselines/reference/classInheritence.js
+++ b/tests/baselines/reference/classInheritence.js
@@ -11,16 +11,14 @@ var __extends = (this && this.__extends) || function (d, b) {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
 var A = (function (_super) {
     __extends(A, _super);
     function A() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return A;
 }(A));
diff --git a/tests/baselines/reference/classIsSubtypeOfBaseType.js b/tests/baselines/reference/classIsSubtypeOfBaseType.js
index 6caa97781dd..52300987d8e 100644
--- a/tests/baselines/reference/classIsSubtypeOfBaseType.js
+++ b/tests/baselines/reference/classIsSubtypeOfBaseType.js
@@ -29,16 +29,14 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/classOrder2.js b/tests/baselines/reference/classOrder2.js
index 49b2a428e06..63490fa29b1 100644
--- a/tests/baselines/reference/classOrder2.js
+++ b/tests/baselines/reference/classOrder2.js
@@ -28,8 +28,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var A = (function (_super) {
     __extends(A, _super);
     function A() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     A.prototype.foo = function () { this.bar(); };
     return A;
diff --git a/tests/baselines/reference/classOrderBug.js b/tests/baselines/reference/classOrderBug.js
index 1381df2797d..e21a5ed64cf 100644
--- a/tests/baselines/reference/classOrderBug.js
+++ b/tests/baselines/reference/classOrderBug.js
@@ -35,8 +35,7 @@ var baz = (function () {
 var foo = (function (_super) {
     __extends(foo, _super);
     function foo() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return foo;
 }(baz));
diff --git a/tests/baselines/reference/classSideInheritance1.js b/tests/baselines/reference/classSideInheritance1.js
index 7898ae8a2b2..9443509032c 100644
--- a/tests/baselines/reference/classSideInheritance1.js
+++ b/tests/baselines/reference/classSideInheritance1.js
@@ -33,8 +33,7 @@ var A = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }(A));
diff --git a/tests/baselines/reference/classWithBaseClassButNoConstructor.js b/tests/baselines/reference/classWithBaseClassButNoConstructor.js
index 6ff5ae2ac5b..c25687d3c74 100644
--- a/tests/baselines/reference/classWithBaseClassButNoConstructor.js
+++ b/tests/baselines/reference/classWithBaseClassButNoConstructor.js
@@ -54,8 +54,7 @@ var Base = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(Base));
@@ -70,8 +69,7 @@ var Base2 = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(Base2));
@@ -82,8 +80,7 @@ var d2 = new D(1); // ok
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D2;
 }(Base2));
@@ -93,8 +90,7 @@ var d4 = new D(1); // ok
 var D3 = (function (_super) {
     __extends(D3, _super);
     function D3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D3;
 }(Base2));
diff --git a/tests/baselines/reference/classWithConstructors.js b/tests/baselines/reference/classWithConstructors.js
index 6bb9387f673..f445d22d18f 100644
--- a/tests/baselines/reference/classWithConstructors.js
+++ b/tests/baselines/reference/classWithConstructors.js
@@ -75,8 +75,7 @@ var NonGeneric;
     var D = (function (_super) {
         __extends(D, _super);
         function D() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D;
     }(C2));
@@ -104,8 +103,7 @@ var Generics;
     var D = (function (_super) {
         __extends(D, _super);
         function D() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D;
     }(C2));
diff --git a/tests/baselines/reference/classWithProtectedProperty.js b/tests/baselines/reference/classWithProtectedProperty.js
index fb07eb3d0b2..2cb8a4e0a50 100644
--- a/tests/baselines/reference/classWithProtectedProperty.js
+++ b/tests/baselines/reference/classWithProtectedProperty.js
@@ -48,8 +48,7 @@ C.g = function () { return ''; };
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     D.prototype.method = function () {
         // No errors
diff --git a/tests/baselines/reference/classWithStaticMembers.js b/tests/baselines/reference/classWithStaticMembers.js
index cd23c220231..9e79780d5cc 100644
--- a/tests/baselines/reference/classWithStaticMembers.js
+++ b/tests/baselines/reference/classWithStaticMembers.js
@@ -45,8 +45,7 @@ var r3 = r.foo;
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/classdecl.js b/tests/baselines/reference/classdecl.js
index d4f6bb11ca9..a3059757d2f 100644
--- a/tests/baselines/reference/classdecl.js
+++ b/tests/baselines/reference/classdecl.js
@@ -136,8 +136,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return b;
 }(a));
@@ -162,8 +161,7 @@ var m2;
         var c = (function (_super) {
             __extends(c, _super);
             function c() {
-                var _this = _super.apply(this, arguments) || this;
-                return _this;
+                return _super.apply(this, arguments) || this;
             }
             return c;
         }(b));
@@ -179,8 +177,7 @@ var m2;
 var c = (function (_super) {
     __extends(c, _super);
     function c() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return c;
 }(m1.b));
diff --git a/tests/baselines/reference/clodulesDerivedClasses.js b/tests/baselines/reference/clodulesDerivedClasses.js
index dbbbe340ba7..f65295627f1 100644
--- a/tests/baselines/reference/clodulesDerivedClasses.js
+++ b/tests/baselines/reference/clodulesDerivedClasses.js
@@ -44,8 +44,7 @@ var Shape;
 var Path = (function (_super) {
     __extends(Path, _super);
     function Path() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Path;
 }(Shape));
diff --git a/tests/baselines/reference/collisionSuperAndLocalFunctionInAccessors.js b/tests/baselines/reference/collisionSuperAndLocalFunctionInAccessors.js
index eaf031c2571..85c0e398fbd 100644
--- a/tests/baselines/reference/collisionSuperAndLocalFunctionInAccessors.js
+++ b/tests/baselines/reference/collisionSuperAndLocalFunctionInAccessors.js
@@ -68,8 +68,7 @@ var Foo = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Object.defineProperty(b.prototype, "prop2", {
         get: function () {
@@ -89,8 +88,7 @@ var b = (function (_super) {
 var c = (function (_super) {
     __extends(c, _super);
     function c() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Object.defineProperty(c.prototype, "prop2", {
         get: function () {
diff --git a/tests/baselines/reference/collisionSuperAndLocalFunctionInMethod.js b/tests/baselines/reference/collisionSuperAndLocalFunctionInMethod.js
index 14965b53abd..81c069da169 100644
--- a/tests/baselines/reference/collisionSuperAndLocalFunctionInMethod.js
+++ b/tests/baselines/reference/collisionSuperAndLocalFunctionInMethod.js
@@ -50,8 +50,7 @@ var Foo = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     b.prototype.foo = function () {
         function _super() {
@@ -64,8 +63,7 @@ var b = (function (_super) {
 var c = (function (_super) {
     __extends(c, _super);
     function c() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     c.prototype.foo = function () {
         var x = function () {
diff --git a/tests/baselines/reference/collisionSuperAndLocalVarInAccessors.js b/tests/baselines/reference/collisionSuperAndLocalVarInAccessors.js
index 55db3a5e625..26f782c0d17 100644
--- a/tests/baselines/reference/collisionSuperAndLocalVarInAccessors.js
+++ b/tests/baselines/reference/collisionSuperAndLocalVarInAccessors.js
@@ -58,8 +58,7 @@ var Foo = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Object.defineProperty(b.prototype, "prop2", {
         get: function () {
@@ -77,8 +76,7 @@ var b = (function (_super) {
 var c = (function (_super) {
     __extends(c, _super);
     function c() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Object.defineProperty(c.prototype, "prop2", {
         get: function () {
diff --git a/tests/baselines/reference/collisionSuperAndLocalVarInMethod.js b/tests/baselines/reference/collisionSuperAndLocalVarInMethod.js
index c5bb6ebcd01..0524d993ba1 100644
--- a/tests/baselines/reference/collisionSuperAndLocalVarInMethod.js
+++ b/tests/baselines/reference/collisionSuperAndLocalVarInMethod.js
@@ -36,8 +36,7 @@ var Foo = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     b.prototype.foo = function () {
         var _super = 10; // Should be error 
@@ -47,8 +46,7 @@ var b = (function (_super) {
 var c = (function (_super) {
     __extends(c, _super);
     function c() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     c.prototype.foo = function () {
         var x = function () {
diff --git a/tests/baselines/reference/collisionSuperAndNameResolution.js b/tests/baselines/reference/collisionSuperAndNameResolution.js
index 5501b3e2df4..cb5636ec904 100644
--- a/tests/baselines/reference/collisionSuperAndNameResolution.js
+++ b/tests/baselines/reference/collisionSuperAndNameResolution.js
@@ -27,8 +27,7 @@ var base = (function () {
 var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Foo.prototype.x = function () {
         console.log(_super); // Error as this doesnt not resolve to user defined _super
diff --git a/tests/baselines/reference/collisionSuperAndParameter1.js b/tests/baselines/reference/collisionSuperAndParameter1.js
index 105fe849767..ed19500f9d4 100644
--- a/tests/baselines/reference/collisionSuperAndParameter1.js
+++ b/tests/baselines/reference/collisionSuperAndParameter1.js
@@ -23,8 +23,7 @@ var Foo = (function () {
 var Foo2 = (function (_super) {
     __extends(Foo2, _super);
     function Foo2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Foo2.prototype.x = function () {
         var lambda = function (_super) {
diff --git a/tests/baselines/reference/collisionThisExpressionAndLocalVarWithSuperExperssion.js b/tests/baselines/reference/collisionThisExpressionAndLocalVarWithSuperExperssion.js
index 59b64e4a9ba..9e8132c6883 100644
--- a/tests/baselines/reference/collisionThisExpressionAndLocalVarWithSuperExperssion.js
+++ b/tests/baselines/reference/collisionThisExpressionAndLocalVarWithSuperExperssion.js
@@ -34,8 +34,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     b.prototype.foo = function () {
         var _this = this;
@@ -47,8 +46,7 @@ var b = (function (_super) {
 var b2 = (function (_super) {
     __extends(b2, _super);
     function b2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     b2.prototype.foo = function () {
         var _this = this;
diff --git a/tests/baselines/reference/commentsInheritance.js b/tests/baselines/reference/commentsInheritance.js
index a8a8d5fa889..3527f5d23bb 100644
--- a/tests/baselines/reference/commentsInheritance.js
+++ b/tests/baselines/reference/commentsInheritance.js
@@ -258,8 +258,7 @@ c2_i = c3_i;
 var c4 = (function (_super) {
     __extends(c4, _super);
     function c4() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return c4;
 }(c2));
diff --git a/tests/baselines/reference/comparisonOperatorWithIdenticalObjects.js b/tests/baselines/reference/comparisonOperatorWithIdenticalObjects.js
index fb7a811cba3..a263a30e382 100644
--- a/tests/baselines/reference/comparisonOperatorWithIdenticalObjects.js
+++ b/tests/baselines/reference/comparisonOperatorWithIdenticalObjects.js
@@ -227,16 +227,14 @@ var Base = (function () {
 var A2 = (function (_super) {
     __extends(A2, _super);
     function A2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return A2;
 }(Base));
 var B2 = (function (_super) {
     __extends(B2, _super);
     function B2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B2;
 }(Base));
diff --git a/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnCallSignature.js b/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnCallSignature.js
index 675235ae324..b8584522b7b 100644
--- a/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnCallSignature.js
+++ b/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnCallSignature.js
@@ -182,8 +182,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnConstructorSignature.js b/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnConstructorSignature.js
index ceb386b3e14..93e1e876a7f 100644
--- a/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnConstructorSignature.js
+++ b/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnConstructorSignature.js
@@ -182,8 +182,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnIndexSignature.js b/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnIndexSignature.js
index 03494b4f88d..a8973bf2c10 100644
--- a/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnIndexSignature.js
+++ b/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnIndexSignature.js
@@ -125,8 +125,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnInstantiatedCallSignature.js b/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnInstantiatedCallSignature.js
index ee8185802d4..4539538782d 100644
--- a/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnInstantiatedCallSignature.js
+++ b/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnInstantiatedCallSignature.js
@@ -163,8 +163,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnInstantiatedConstructorSignature.js b/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnInstantiatedConstructorSignature.js
index 5a36f91c7ca..5e8412bc361 100644
--- a/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnInstantiatedConstructorSignature.js
+++ b/tests/baselines/reference/comparisonOperatorWithNoRelationshipObjectsOnInstantiatedConstructorSignature.js
@@ -163,8 +163,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnCallSignature.js b/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnCallSignature.js
index f23588dcbc5..d30c3586b12 100644
--- a/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnCallSignature.js
+++ b/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnCallSignature.js
@@ -273,8 +273,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnConstructorSignature.js b/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnConstructorSignature.js
index cc6fe9ce640..4235c1352d4 100644
--- a/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnConstructorSignature.js
+++ b/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnConstructorSignature.js
@@ -235,8 +235,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnIndexSignature.js b/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnIndexSignature.js
index d401defc2ed..9a6fecd668d 100644
--- a/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnIndexSignature.js
+++ b/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnIndexSignature.js
@@ -121,8 +121,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnInstantiatedCallSignature.js b/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnInstantiatedCallSignature.js
index b4b531b8084..5721a452486 100644
--- a/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnInstantiatedCallSignature.js
+++ b/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnInstantiatedCallSignature.js
@@ -178,8 +178,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnInstantiatedConstructorSignature.js b/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnInstantiatedConstructorSignature.js
index 69f46e2ccd2..b6bf8a16e61 100644
--- a/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnInstantiatedConstructorSignature.js
+++ b/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnInstantiatedConstructorSignature.js
@@ -178,8 +178,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnProperty.js b/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnProperty.js
index 171f21e77fc..690214fc00f 100644
--- a/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnProperty.js
+++ b/tests/baselines/reference/comparisonOperatorWithSubtypeObjectOnProperty.js
@@ -92,8 +92,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
@@ -115,8 +114,7 @@ var A2 = (function () {
 var B2 = (function (_super) {
     __extends(B2, _super);
     function B2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B2;
 }(A2));
diff --git a/tests/baselines/reference/complexClassRelationships.js b/tests/baselines/reference/complexClassRelationships.js
index 523002e5b57..4f48e5fc2c5 100644
--- a/tests/baselines/reference/complexClassRelationships.js
+++ b/tests/baselines/reference/complexClassRelationships.js
@@ -57,8 +57,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived.createEmpty = function () {
         var item = new Derived();
diff --git a/tests/baselines/reference/complicatedGenericRecursiveBaseClassReference.js b/tests/baselines/reference/complicatedGenericRecursiveBaseClassReference.js
index 1201dcf3d3d..326c0830c4f 100644
--- a/tests/baselines/reference/complicatedGenericRecursiveBaseClassReference.js
+++ b/tests/baselines/reference/complicatedGenericRecursiveBaseClassReference.js
@@ -14,8 +14,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var S18 = (function (_super) {
     __extends(S18, _super);
     function S18() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return S18;
 }(S18));
diff --git a/tests/baselines/reference/computedPropertyNames24_ES5.js b/tests/baselines/reference/computedPropertyNames24_ES5.js
index 00186f40a28..ff9112755bd 100644
--- a/tests/baselines/reference/computedPropertyNames24_ES5.js
+++ b/tests/baselines/reference/computedPropertyNames24_ES5.js
@@ -25,8 +25,7 @@ var Base = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     C.prototype[_super.bar.call(this)] = function () { };
     return C;
diff --git a/tests/baselines/reference/computedPropertyNames25_ES5.js b/tests/baselines/reference/computedPropertyNames25_ES5.js
index afc0e20eca9..dad9c5c291a 100644
--- a/tests/baselines/reference/computedPropertyNames25_ES5.js
+++ b/tests/baselines/reference/computedPropertyNames25_ES5.js
@@ -30,8 +30,7 @@ var Base = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     C.prototype.foo = function () {
         var obj = (_a = {},
diff --git a/tests/baselines/reference/computedPropertyNames26_ES5.js b/tests/baselines/reference/computedPropertyNames26_ES5.js
index 6b75da57e9a..5db7768270a 100644
--- a/tests/baselines/reference/computedPropertyNames26_ES5.js
+++ b/tests/baselines/reference/computedPropertyNames26_ES5.js
@@ -27,8 +27,7 @@ var Base = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     C.prototype[(_a = {}, _a[_super.bar.call(this)] = 1, _a)[0]] = function () { };
     return C;
diff --git a/tests/baselines/reference/computedPropertyNames27_ES5.js b/tests/baselines/reference/computedPropertyNames27_ES5.js
index 3c89ecd50c0..381805659e2 100644
--- a/tests/baselines/reference/computedPropertyNames27_ES5.js
+++ b/tests/baselines/reference/computedPropertyNames27_ES5.js
@@ -19,8 +19,7 @@ var Base = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     C.prototype[(_this = _super.call(this) || this, "prop")] = function () { };
     return C;
diff --git a/tests/baselines/reference/computedPropertyNames31_ES5.js b/tests/baselines/reference/computedPropertyNames31_ES5.js
index 7b803e9c987..00cc765f4cc 100644
--- a/tests/baselines/reference/computedPropertyNames31_ES5.js
+++ b/tests/baselines/reference/computedPropertyNames31_ES5.js
@@ -32,8 +32,7 @@ var Base = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     C.prototype.foo = function () {
         var _this = this;
diff --git a/tests/baselines/reference/computedPropertyNames43_ES5.js b/tests/baselines/reference/computedPropertyNames43_ES5.js
index 293d017734e..b1bb0fec72c 100644
--- a/tests/baselines/reference/computedPropertyNames43_ES5.js
+++ b/tests/baselines/reference/computedPropertyNames43_ES5.js
@@ -36,8 +36,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Object.defineProperty(D.prototype, "get1", {
         // Computed properties
diff --git a/tests/baselines/reference/computedPropertyNames44_ES5.js b/tests/baselines/reference/computedPropertyNames44_ES5.js
index c990298c4ac..bf940f15014 100644
--- a/tests/baselines/reference/computedPropertyNames44_ES5.js
+++ b/tests/baselines/reference/computedPropertyNames44_ES5.js
@@ -40,8 +40,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Object.defineProperty(D.prototype, "set1", {
         set: function (p) { },
diff --git a/tests/baselines/reference/computedPropertyNames45_ES5.js b/tests/baselines/reference/computedPropertyNames45_ES5.js
index f5a31fffabb..5b5d64f9bf0 100644
--- a/tests/baselines/reference/computedPropertyNames45_ES5.js
+++ b/tests/baselines/reference/computedPropertyNames45_ES5.js
@@ -41,8 +41,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Object.defineProperty(D.prototype, "set1", {
         set: function (p) { },
diff --git a/tests/baselines/reference/conditionalOperatorWithIdenticalBCT.js b/tests/baselines/reference/conditionalOperatorWithIdenticalBCT.js
index a6d00d847f3..408571af42a 100644
--- a/tests/baselines/reference/conditionalOperatorWithIdenticalBCT.js
+++ b/tests/baselines/reference/conditionalOperatorWithIdenticalBCT.js
@@ -63,8 +63,7 @@ var X = (function () {
 var A = (function (_super) {
     __extends(A, _super);
     function A() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return A;
 }(X));
@@ -72,8 +71,7 @@ var A = (function (_super) {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(X));
diff --git a/tests/baselines/reference/conditionalOperatorWithoutIdenticalBCT.js b/tests/baselines/reference/conditionalOperatorWithoutIdenticalBCT.js
index 58b050c5ebe..0ac935a582a 100644
--- a/tests/baselines/reference/conditionalOperatorWithoutIdenticalBCT.js
+++ b/tests/baselines/reference/conditionalOperatorWithoutIdenticalBCT.js
@@ -39,8 +39,7 @@ var X = (function () {
 var A = (function (_super) {
     __extends(A, _super);
     function A() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return A;
 }(X));
@@ -48,8 +47,7 @@ var A = (function (_super) {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(X));
diff --git a/tests/baselines/reference/constantOverloadFunction.js b/tests/baselines/reference/constantOverloadFunction.js
index 934c7eceb0e..160191c5ca0 100644
--- a/tests/baselines/reference/constantOverloadFunction.js
+++ b/tests/baselines/reference/constantOverloadFunction.js
@@ -28,8 +28,7 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived1.prototype.bar = function () { };
     return Derived1;
@@ -37,8 +36,7 @@ var Derived1 = (function (_super) {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived2.prototype.baz = function () { };
     return Derived2;
@@ -46,8 +44,7 @@ var Derived2 = (function (_super) {
 var Derived3 = (function (_super) {
     __extends(Derived3, _super);
     function Derived3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived3.prototype.biz = function () { };
     return Derived3;
diff --git a/tests/baselines/reference/constantOverloadFunctionNoSubtypeError.js b/tests/baselines/reference/constantOverloadFunctionNoSubtypeError.js
index 217cf23f9cb..509f9ba70e6 100644
--- a/tests/baselines/reference/constantOverloadFunctionNoSubtypeError.js
+++ b/tests/baselines/reference/constantOverloadFunctionNoSubtypeError.js
@@ -29,8 +29,7 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived1.prototype.bar = function () { };
     return Derived1;
@@ -38,8 +37,7 @@ var Derived1 = (function (_super) {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived2.prototype.baz = function () { };
     return Derived2;
@@ -47,8 +45,7 @@ var Derived2 = (function (_super) {
 var Derived3 = (function (_super) {
     __extends(Derived3, _super);
     function Derived3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived3.prototype.biz = function () { };
     return Derived3;
diff --git a/tests/baselines/reference/constraintCheckInGenericBaseTypeReference.js b/tests/baselines/reference/constraintCheckInGenericBaseTypeReference.js
index 511c293d417..7908d36a56a 100644
--- a/tests/baselines/reference/constraintCheckInGenericBaseTypeReference.js
+++ b/tests/baselines/reference/constraintCheckInGenericBaseTypeReference.js
@@ -40,8 +40,7 @@ var GenericBase = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(GenericBase));
diff --git a/tests/baselines/reference/constructSignatureAssignabilityInInheritance2.js b/tests/baselines/reference/constructSignatureAssignabilityInInheritance2.js
index 0e14e958b28..6b308d88896 100644
--- a/tests/baselines/reference/constructSignatureAssignabilityInInheritance2.js
+++ b/tests/baselines/reference/constructSignatureAssignabilityInInheritance2.js
@@ -84,24 +84,21 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/constructSignatureAssignabilityInInheritance3.js b/tests/baselines/reference/constructSignatureAssignabilityInInheritance3.js
index cb2cadb7698..09abd6e0868 100644
--- a/tests/baselines/reference/constructSignatureAssignabilityInInheritance3.js
+++ b/tests/baselines/reference/constructSignatureAssignabilityInInheritance3.js
@@ -129,24 +129,21 @@ var Errors;
     var Derived = (function (_super) {
         __extends(Derived, _super);
         function Derived() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Derived;
     }(Base));
     var Derived2 = (function (_super) {
         __extends(Derived2, _super);
         function Derived2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Derived2;
     }(Derived));
     var OtherDerived = (function (_super) {
         __extends(OtherDerived, _super);
         function OtherDerived() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return OtherDerived;
     }(Base));
diff --git a/tests/baselines/reference/constructSignatureAssignabilityInInheritance4.js b/tests/baselines/reference/constructSignatureAssignabilityInInheritance4.js
index 25c69839117..4e9a8c59bf9 100644
--- a/tests/baselines/reference/constructSignatureAssignabilityInInheritance4.js
+++ b/tests/baselines/reference/constructSignatureAssignabilityInInheritance4.js
@@ -74,24 +74,21 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/constructSignatureAssignabilityInInheritance5.js b/tests/baselines/reference/constructSignatureAssignabilityInInheritance5.js
index dcd972d3a97..91ec3b313bb 100644
--- a/tests/baselines/reference/constructSignatureAssignabilityInInheritance5.js
+++ b/tests/baselines/reference/constructSignatureAssignabilityInInheritance5.js
@@ -64,24 +64,21 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/constructSignatureAssignabilityInInheritance6.js b/tests/baselines/reference/constructSignatureAssignabilityInInheritance6.js
index 69fdebe8f5c..edafb009916 100644
--- a/tests/baselines/reference/constructSignatureAssignabilityInInheritance6.js
+++ b/tests/baselines/reference/constructSignatureAssignabilityInInheritance6.js
@@ -67,24 +67,21 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType.js b/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType.js
index b16721d0acc..45ed976e191 100644
--- a/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType.js
+++ b/tests/baselines/reference/constructorFunctionTypeIsAssignableToBaseType.js
@@ -33,16 +33,14 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/constructorHasPrototypeProperty.js b/tests/baselines/reference/constructorHasPrototypeProperty.js
index 956e8cd2e0d..a16694cdbf5 100644
--- a/tests/baselines/reference/constructorHasPrototypeProperty.js
+++ b/tests/baselines/reference/constructorHasPrototypeProperty.js
@@ -47,8 +47,7 @@ var NonGeneric;
     var D = (function (_super) {
         __extends(D, _super);
         function D() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D;
     }(C));
@@ -67,8 +66,7 @@ var Generic;
     var D = (function (_super) {
         __extends(D, _super);
         function D() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D;
     }(C));
diff --git a/tests/baselines/reference/constructorWithIncompleteTypeAnnotation.js b/tests/baselines/reference/constructorWithIncompleteTypeAnnotation.js
index 1b91e8a131a..2e3190c15c8 100644
--- a/tests/baselines/reference/constructorWithIncompleteTypeAnnotation.js
+++ b/tests/baselines/reference/constructorWithIncompleteTypeAnnotation.js
@@ -525,8 +525,7 @@ method2();
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     B.prototype.method2 = function () {
         return this.method1(2);
diff --git a/tests/baselines/reference/contextualTypingArrayOfLambdas.js b/tests/baselines/reference/contextualTypingArrayOfLambdas.js
index 365e17afc9b..caf7ed445e5 100644
--- a/tests/baselines/reference/contextualTypingArrayOfLambdas.js
+++ b/tests/baselines/reference/contextualTypingArrayOfLambdas.js
@@ -28,16 +28,14 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/contextualTypingOfConditionalExpression.js b/tests/baselines/reference/contextualTypingOfConditionalExpression.js
index 7be8079cfd9..a6ce98f61e2 100644
--- a/tests/baselines/reference/contextualTypingOfConditionalExpression.js
+++ b/tests/baselines/reference/contextualTypingOfConditionalExpression.js
@@ -29,16 +29,14 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/contextualTypingOfConditionalExpression2.js b/tests/baselines/reference/contextualTypingOfConditionalExpression2.js
index 102562a841a..e3bd1643cfb 100644
--- a/tests/baselines/reference/contextualTypingOfConditionalExpression2.js
+++ b/tests/baselines/reference/contextualTypingOfConditionalExpression2.js
@@ -26,16 +26,14 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/crashInsourcePropertyIsRelatableToTargetProperty.js b/tests/baselines/reference/crashInsourcePropertyIsRelatableToTargetProperty.js
index 5fafe95c1a8..89979da4812 100644
--- a/tests/baselines/reference/crashInsourcePropertyIsRelatableToTargetProperty.js
+++ b/tests/baselines/reference/crashInsourcePropertyIsRelatableToTargetProperty.js
@@ -25,8 +25,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/declFileClassExtendsNull.js b/tests/baselines/reference/declFileClassExtendsNull.js
index 58bff801774..30ddc3f08bf 100644
--- a/tests/baselines/reference/declFileClassExtendsNull.js
+++ b/tests/baselines/reference/declFileClassExtendsNull.js
@@ -12,8 +12,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var ExtendsNull = (function (_super) {
     __extends(ExtendsNull, _super);
     function ExtendsNull() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return ExtendsNull;
 }(null));
diff --git a/tests/baselines/reference/declFileForFunctionTypeAsTypeParameter.js b/tests/baselines/reference/declFileForFunctionTypeAsTypeParameter.js
index d58dcd1f536..442007d9b9a 100644
--- a/tests/baselines/reference/declFileForFunctionTypeAsTypeParameter.js
+++ b/tests/baselines/reference/declFileForFunctionTypeAsTypeParameter.js
@@ -23,8 +23,7 @@ var X = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(X));
diff --git a/tests/baselines/reference/declFileGenericClassWithGenericExtendedClass.js b/tests/baselines/reference/declFileGenericClassWithGenericExtendedClass.js
index 2f68300a4bf..47593dc9d68 100644
--- a/tests/baselines/reference/declFileGenericClassWithGenericExtendedClass.js
+++ b/tests/baselines/reference/declFileGenericClassWithGenericExtendedClass.js
@@ -26,8 +26,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/declFileGenericType.js b/tests/baselines/reference/declFileGenericType.js
index 2ed404342d7..b2e99a73ad7 100644
--- a/tests/baselines/reference/declFileGenericType.js
+++ b/tests/baselines/reference/declFileGenericType.js
@@ -91,8 +91,7 @@ exports.g = C.F5();
 var h = (function (_super) {
     __extends(h, _super);
     function h() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return h;
 }(C.A));
diff --git a/tests/baselines/reference/declFileWithClassNameConflictingWithClassReferredByExtendsClause.js b/tests/baselines/reference/declFileWithClassNameConflictingWithClassReferredByExtendsClause.js
index c9c569f8676..cd10a9e9456 100644
--- a/tests/baselines/reference/declFileWithClassNameConflictingWithClassReferredByExtendsClause.js
+++ b/tests/baselines/reference/declFileWithClassNameConflictingWithClassReferredByExtendsClause.js
@@ -35,8 +35,7 @@ var X;
             var W = (function (_super) {
                 __extends(W, _super);
                 function W() {
-                    var _this = _super.apply(this, arguments) || this;
-                    return _this;
+                    return _super.apply(this, arguments) || this;
                 }
                 return W;
             }(A.B.Base.W));
@@ -55,8 +54,7 @@ var X;
                 var W = (function (_super) {
                     __extends(W, _super);
                     function W() {
-                        var _this = _super.apply(this, arguments) || this;
-                        return _this;
+                        return _super.apply(this, arguments) || this;
                     }
                     return W;
                 }(X.Y.base.W));
diff --git a/tests/baselines/reference/declFileWithExtendsClauseThatHasItsContainerNameConflict.js b/tests/baselines/reference/declFileWithExtendsClauseThatHasItsContainerNameConflict.js
index 3681f9fa859..f3b93efc9eb 100644
--- a/tests/baselines/reference/declFileWithExtendsClauseThatHasItsContainerNameConflict.js
+++ b/tests/baselines/reference/declFileWithExtendsClauseThatHasItsContainerNameConflict.js
@@ -45,8 +45,7 @@ var A;
             var ContextMenu = (function (_super) {
                 __extends(ContextMenu, _super);
                 function ContextMenu() {
-                    var _this = _super.apply(this, arguments) || this;
-                    return _this;
+                    return _super.apply(this, arguments) || this;
                 }
                 return ContextMenu;
             }(B.EventManager));
diff --git a/tests/baselines/reference/declarationEmitExpressionInExtends.js b/tests/baselines/reference/declarationEmitExpressionInExtends.js
index 8973fbb1455..726c7b22446 100644
--- a/tests/baselines/reference/declarationEmitExpressionInExtends.js
+++ b/tests/baselines/reference/declarationEmitExpressionInExtends.js
@@ -29,8 +29,7 @@ var Q = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(x));
diff --git a/tests/baselines/reference/declarationEmitExpressionInExtends2.js b/tests/baselines/reference/declarationEmitExpressionInExtends2.js
index ff75df8baba..4081de6d3ed 100644
--- a/tests/baselines/reference/declarationEmitExpressionInExtends2.js
+++ b/tests/baselines/reference/declarationEmitExpressionInExtends2.js
@@ -29,8 +29,7 @@ function getClass(c) {
 var MyClass = (function (_super) {
     __extends(MyClass, _super);
     function MyClass() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return MyClass;
 }(getClass(2)));
diff --git a/tests/baselines/reference/declarationEmitExpressionInExtends3.js b/tests/baselines/reference/declarationEmitExpressionInExtends3.js
index fc73eb5dbd0..f36a7e250a2 100644
--- a/tests/baselines/reference/declarationEmitExpressionInExtends3.js
+++ b/tests/baselines/reference/declarationEmitExpressionInExtends3.js
@@ -70,8 +70,7 @@ function getExportedClass(c) {
 var MyClass = (function (_super) {
     __extends(MyClass, _super);
     function MyClass() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return MyClass;
 }(getLocalClass(undefined)));
@@ -79,8 +78,7 @@ exports.MyClass = MyClass;
 var MyClass2 = (function (_super) {
     __extends(MyClass2, _super);
     function MyClass2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return MyClass2;
 }(getExportedClass(undefined)));
@@ -88,8 +86,7 @@ exports.MyClass2 = MyClass2;
 var MyClass3 = (function (_super) {
     __extends(MyClass3, _super);
     function MyClass3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return MyClass3;
 }(getExportedClass(undefined)));
@@ -97,8 +94,7 @@ exports.MyClass3 = MyClass3;
 var MyClass4 = (function (_super) {
     __extends(MyClass4, _super);
     function MyClass4() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return MyClass4;
 }(getExportedClass(undefined)));
diff --git a/tests/baselines/reference/declarationEmitExpressionInExtends4.js b/tests/baselines/reference/declarationEmitExpressionInExtends4.js
index ed34544256b..b90c1275197 100644
--- a/tests/baselines/reference/declarationEmitExpressionInExtends4.js
+++ b/tests/baselines/reference/declarationEmitExpressionInExtends4.js
@@ -33,24 +33,21 @@ function getSomething() {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(getSomething()));
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }(SomeUndefinedFunction()));
 var C3 = (function (_super) {
     __extends(C3, _super);
     function C3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C3;
 }(SomeUndefinedFunction));
diff --git a/tests/baselines/reference/declarationEmitNameConflicts3.js b/tests/baselines/reference/declarationEmitNameConflicts3.js
index c17f624087d..09dcea089a8 100644
--- a/tests/baselines/reference/declarationEmitNameConflicts3.js
+++ b/tests/baselines/reference/declarationEmitNameConflicts3.js
@@ -64,8 +64,7 @@ var M;
         var E = (function (_super) {
             __extends(E, _super);
             function E() {
-                var _this = _super.apply(this, arguments) || this;
-                return _this;
+                return _super.apply(this, arguments) || this;
             }
             return E;
         }(C));
diff --git a/tests/baselines/reference/declarationEmitProtectedMembers.js b/tests/baselines/reference/declarationEmitProtectedMembers.js
index cc4e27895f1..9ae8e8a2437 100644
--- a/tests/baselines/reference/declarationEmitProtectedMembers.js
+++ b/tests/baselines/reference/declarationEmitProtectedMembers.js
@@ -88,8 +88,7 @@ var C1 = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     C2.prototype.f = function () {
         return _super.prototype.f.call(this) + this.x;
@@ -103,8 +102,7 @@ var C2 = (function (_super) {
 var C3 = (function (_super) {
     __extends(C3, _super);
     function C3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     C3.prototype.f = function () {
         return _super.prototype.f.call(this);
diff --git a/tests/baselines/reference/declarationEmitThisPredicates01.js b/tests/baselines/reference/declarationEmitThisPredicates01.js
index 0b364e90e45..ad9b7a70373 100644
--- a/tests/baselines/reference/declarationEmitThisPredicates01.js
+++ b/tests/baselines/reference/declarationEmitThisPredicates01.js
@@ -28,8 +28,7 @@ exports.C = C;
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/declarationEmitThisPredicatesWithPrivateName01.js b/tests/baselines/reference/declarationEmitThisPredicatesWithPrivateName01.js
index aea36311add..fe7995462ef 100644
--- a/tests/baselines/reference/declarationEmitThisPredicatesWithPrivateName01.js
+++ b/tests/baselines/reference/declarationEmitThisPredicatesWithPrivateName01.js
@@ -28,8 +28,7 @@ exports.C = C;
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/declareDottedExtend.js b/tests/baselines/reference/declareDottedExtend.js
index f167928087d..3c7588d2b6c 100644
--- a/tests/baselines/reference/declareDottedExtend.js
+++ b/tests/baselines/reference/declareDottedExtend.js
@@ -21,16 +21,14 @@ var ab = A.B;
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(ab.C));
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return E;
 }(A.B.C));
diff --git a/tests/baselines/reference/decoratorOnClassMethod12.js b/tests/baselines/reference/decoratorOnClassMethod12.js
index 6d95c696176..7dd5f698182 100644
--- a/tests/baselines/reference/decoratorOnClassMethod12.js
+++ b/tests/baselines/reference/decoratorOnClassMethod12.js
@@ -32,8 +32,7 @@ var M;
     var C = (function (_super) {
         __extends(C, _super);
         function C() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         C.prototype.method = function () { };
         return C;
diff --git a/tests/baselines/reference/derivedClassFunctionOverridesBaseClassAccessor.js b/tests/baselines/reference/derivedClassFunctionOverridesBaseClassAccessor.js
index 6dcf8f3fd83..7f6b83593ca 100644
--- a/tests/baselines/reference/derivedClassFunctionOverridesBaseClassAccessor.js
+++ b/tests/baselines/reference/derivedClassFunctionOverridesBaseClassAccessor.js
@@ -38,8 +38,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived.prototype.x = function () {
         return 1;
diff --git a/tests/baselines/reference/derivedClassIncludesInheritedMembers.js b/tests/baselines/reference/derivedClassIncludesInheritedMembers.js
index 2fe5906e746..8224473cb54 100644
--- a/tests/baselines/reference/derivedClassIncludesInheritedMembers.js
+++ b/tests/baselines/reference/derivedClassIncludesInheritedMembers.js
@@ -68,8 +68,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
@@ -90,8 +89,7 @@ var Base2 = (function () {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Base2));
diff --git a/tests/baselines/reference/derivedClassOverridesIndexersWithAssignmentCompatibility.js b/tests/baselines/reference/derivedClassOverridesIndexersWithAssignmentCompatibility.js
index dc63ccb21d8..4753e395390 100644
--- a/tests/baselines/reference/derivedClassOverridesIndexersWithAssignmentCompatibility.js
+++ b/tests/baselines/reference/derivedClassOverridesIndexersWithAssignmentCompatibility.js
@@ -32,8 +32,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
@@ -46,8 +45,7 @@ var Base2 = (function () {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Base2));
diff --git a/tests/baselines/reference/derivedClassOverridesPrivates.js b/tests/baselines/reference/derivedClassOverridesPrivates.js
index 7ab70d93ff2..1a58c038fea 100644
--- a/tests/baselines/reference/derivedClassOverridesPrivates.js
+++ b/tests/baselines/reference/derivedClassOverridesPrivates.js
@@ -29,8 +29,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
@@ -42,8 +41,7 @@ var Base2 = (function () {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Base2));
diff --git a/tests/baselines/reference/derivedClassOverridesProtectedMembers2.js b/tests/baselines/reference/derivedClassOverridesProtectedMembers2.js
index ac9b401a45c..6797eef0e77 100644
--- a/tests/baselines/reference/derivedClassOverridesProtectedMembers2.js
+++ b/tests/baselines/reference/derivedClassOverridesProtectedMembers2.js
@@ -131,8 +131,7 @@ var Base2 = (function () {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Base2));
diff --git a/tests/baselines/reference/derivedClassOverridesProtectedMembers4.js b/tests/baselines/reference/derivedClassOverridesProtectedMembers4.js
index eeaf80061af..06f80997600 100644
--- a/tests/baselines/reference/derivedClassOverridesProtectedMembers4.js
+++ b/tests/baselines/reference/derivedClassOverridesProtectedMembers4.js
@@ -30,16 +30,14 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived1;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived1));
diff --git a/tests/baselines/reference/derivedClassOverridesPublicMembers.js b/tests/baselines/reference/derivedClassOverridesPublicMembers.js
index 92fbc07e774..7943d904dea 100644
--- a/tests/baselines/reference/derivedClassOverridesPublicMembers.js
+++ b/tests/baselines/reference/derivedClassOverridesPublicMembers.js
@@ -129,8 +129,7 @@ var Base2 = (function () {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Base2));
diff --git a/tests/baselines/reference/derivedClassOverridesWithoutSubtype.js b/tests/baselines/reference/derivedClassOverridesWithoutSubtype.js
index f2d8f72edfb..e42ff9c9e1d 100644
--- a/tests/baselines/reference/derivedClassOverridesWithoutSubtype.js
+++ b/tests/baselines/reference/derivedClassOverridesWithoutSubtype.js
@@ -37,8 +37,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
@@ -50,8 +49,7 @@ var Base2 = (function () {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Base2));
diff --git a/tests/baselines/reference/derivedClassTransitivity.js b/tests/baselines/reference/derivedClassTransitivity.js
index 0e88d3664c6..a76ac8101a0 100644
--- a/tests/baselines/reference/derivedClassTransitivity.js
+++ b/tests/baselines/reference/derivedClassTransitivity.js
@@ -36,8 +36,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     D.prototype.foo = function () { }; // ok to drop parameters
     return D;
@@ -45,8 +44,7 @@ var D = (function (_super) {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     E.prototype.foo = function (x) { }; // ok to add optional parameters
     return E;
diff --git a/tests/baselines/reference/derivedClassTransitivity2.js b/tests/baselines/reference/derivedClassTransitivity2.js
index 5a3f8f3cf57..a3894863696 100644
--- a/tests/baselines/reference/derivedClassTransitivity2.js
+++ b/tests/baselines/reference/derivedClassTransitivity2.js
@@ -36,8 +36,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     D.prototype.foo = function (x) { }; // ok to drop parameters
     return D;
@@ -45,8 +44,7 @@ var D = (function (_super) {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     E.prototype.foo = function (x, y) { }; // ok to add optional parameters
     return E;
diff --git a/tests/baselines/reference/derivedClassTransitivity3.js b/tests/baselines/reference/derivedClassTransitivity3.js
index f6aa6963795..71dfecb346f 100644
--- a/tests/baselines/reference/derivedClassTransitivity3.js
+++ b/tests/baselines/reference/derivedClassTransitivity3.js
@@ -36,8 +36,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     D.prototype.foo = function (x) { }; // ok to drop parameters
     return D;
@@ -45,8 +44,7 @@ var D = (function (_super) {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     E.prototype.foo = function (x, y) { }; // ok to add optional parameters
     return E;
diff --git a/tests/baselines/reference/derivedClassTransitivity4.js b/tests/baselines/reference/derivedClassTransitivity4.js
index 8d18e311d88..0030ce702d8 100644
--- a/tests/baselines/reference/derivedClassTransitivity4.js
+++ b/tests/baselines/reference/derivedClassTransitivity4.js
@@ -36,8 +36,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     D.prototype.foo = function () { }; // ok to drop parameters
     return D;
@@ -45,8 +44,7 @@ var D = (function (_super) {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     E.prototype.foo = function (x) { }; // ok to add optional parameters
     return E;
diff --git a/tests/baselines/reference/derivedClassWithAny.js b/tests/baselines/reference/derivedClassWithAny.js
index 70885570373..2a199e55861 100644
--- a/tests/baselines/reference/derivedClassWithAny.js
+++ b/tests/baselines/reference/derivedClassWithAny.js
@@ -91,8 +91,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Object.defineProperty(D.prototype, "X", {
         get: function () {
@@ -120,8 +119,7 @@ var D = (function (_super) {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Object.defineProperty(E.prototype, "X", {
         get: function () { return ''; },
diff --git a/tests/baselines/reference/derivedClassWithPrivateInstanceShadowingProtectedInstance.js b/tests/baselines/reference/derivedClassWithPrivateInstanceShadowingProtectedInstance.js
index 24d43468dcf..0542815c4e4 100644
--- a/tests/baselines/reference/derivedClassWithPrivateInstanceShadowingProtectedInstance.js
+++ b/tests/baselines/reference/derivedClassWithPrivateInstanceShadowingProtectedInstance.js
@@ -46,8 +46,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived.prototype.fn = function () {
         return '';
diff --git a/tests/baselines/reference/derivedClassWithPrivateInstanceShadowingPublicInstance.js b/tests/baselines/reference/derivedClassWithPrivateInstanceShadowingPublicInstance.js
index a6b7710ec6d..41869cad416 100644
--- a/tests/baselines/reference/derivedClassWithPrivateInstanceShadowingPublicInstance.js
+++ b/tests/baselines/reference/derivedClassWithPrivateInstanceShadowingPublicInstance.js
@@ -56,8 +56,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived.prototype.fn = function () {
         return '';
diff --git a/tests/baselines/reference/derivedClassWithPrivateStaticShadowingProtectedStatic.js b/tests/baselines/reference/derivedClassWithPrivateStaticShadowingProtectedStatic.js
index 3da7720b77e..10ae3cb35c8 100644
--- a/tests/baselines/reference/derivedClassWithPrivateStaticShadowingProtectedStatic.js
+++ b/tests/baselines/reference/derivedClassWithPrivateStaticShadowingProtectedStatic.js
@@ -45,8 +45,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived.fn = function () {
         return '';
diff --git a/tests/baselines/reference/derivedClassWithPrivateStaticShadowingPublicStatic.js b/tests/baselines/reference/derivedClassWithPrivateStaticShadowingPublicStatic.js
index 57f474affe7..3f2c2a3b811 100644
--- a/tests/baselines/reference/derivedClassWithPrivateStaticShadowingPublicStatic.js
+++ b/tests/baselines/reference/derivedClassWithPrivateStaticShadowingPublicStatic.js
@@ -58,8 +58,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived.fn = function () {
         return '';
diff --git a/tests/baselines/reference/derivedClasses.js b/tests/baselines/reference/derivedClasses.js
index 27947b4f05f..3e097a9b139 100644
--- a/tests/baselines/reference/derivedClasses.js
+++ b/tests/baselines/reference/derivedClasses.js
@@ -39,8 +39,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var Red = (function (_super) {
     __extends(Red, _super);
     function Red() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Red.prototype.shade = function () {
         var _this = this;
@@ -59,8 +58,7 @@ var Color = (function () {
 var Blue = (function (_super) {
     __extends(Blue, _super);
     function Blue() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Blue.prototype.shade = function () {
         var _this = this;
diff --git a/tests/baselines/reference/derivedGenericClassWithAny.js b/tests/baselines/reference/derivedGenericClassWithAny.js
index e31b18e11e7..1822f3fcc47 100644
--- a/tests/baselines/reference/derivedGenericClassWithAny.js
+++ b/tests/baselines/reference/derivedGenericClassWithAny.js
@@ -64,8 +64,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Object.defineProperty(D.prototype, "X", {
         get: function () {
@@ -93,8 +92,7 @@ var D = (function (_super) {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Object.defineProperty(E.prototype, "X", {
         get: function () { return ''; } // error
diff --git a/tests/baselines/reference/derivedTypeAccessesHiddenBaseCallViaSuperPropertyAccess.js b/tests/baselines/reference/derivedTypeAccessesHiddenBaseCallViaSuperPropertyAccess.js
index 4430ad5a31b..c17922e05ee 100644
--- a/tests/baselines/reference/derivedTypeAccessesHiddenBaseCallViaSuperPropertyAccess.js
+++ b/tests/baselines/reference/derivedTypeAccessesHiddenBaseCallViaSuperPropertyAccess.js
@@ -34,8 +34,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived.prototype.foo = function (x) {
         return null;
diff --git a/tests/baselines/reference/derivedTypeDoesNotRequireExtendsClause.js b/tests/baselines/reference/derivedTypeDoesNotRequireExtendsClause.js
index f6415d84965..6fe690fd692 100644
--- a/tests/baselines/reference/derivedTypeDoesNotRequireExtendsClause.js
+++ b/tests/baselines/reference/derivedTypeDoesNotRequireExtendsClause.js
@@ -39,8 +39,7 @@ var Derived = (function () {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/emitThisInSuperMethodCall.js b/tests/baselines/reference/emitThisInSuperMethodCall.js
index 4bb83a7c172..1f7ed8bfa94 100644
--- a/tests/baselines/reference/emitThisInSuperMethodCall.js
+++ b/tests/baselines/reference/emitThisInSuperMethodCall.js
@@ -43,8 +43,7 @@ var User = (function () {
 var RegisteredUser = (function (_super) {
     __extends(RegisteredUser, _super);
     function RegisteredUser() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     RegisteredUser.prototype.f = function () {
         (function () {
diff --git a/tests/baselines/reference/emptyModuleName.js b/tests/baselines/reference/emptyModuleName.js
index 2292f0a494a..3ed21cf217a 100644
--- a/tests/baselines/reference/emptyModuleName.js
+++ b/tests/baselines/reference/emptyModuleName.js
@@ -14,8 +14,7 @@ var A = require("");
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/errorForwardReferenceForwadingConstructor.js b/tests/baselines/reference/errorForwardReferenceForwadingConstructor.js
index 7b05688b8c8..ed2e1aa7f06 100644
--- a/tests/baselines/reference/errorForwardReferenceForwadingConstructor.js
+++ b/tests/baselines/reference/errorForwardReferenceForwadingConstructor.js
@@ -30,8 +30,7 @@ var base = (function () {
 var derived = (function (_super) {
     __extends(derived, _super);
     function derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return derived;
 }(base));
diff --git a/tests/baselines/reference/errorSuperPropertyAccess.js b/tests/baselines/reference/errorSuperPropertyAccess.js
index 0fef86493f1..e12a758b053 100644
--- a/tests/baselines/reference/errorSuperPropertyAccess.js
+++ b/tests/baselines/reference/errorSuperPropertyAccess.js
@@ -247,8 +247,7 @@ var SomeDerived2 = (function (_super) {
 var SomeDerived3 = (function (_super) {
     __extends(SomeDerived3, _super);
     function SomeDerived3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     SomeDerived3.fn = function () {
         _super.publicStaticMember = 3;
diff --git a/tests/baselines/reference/errorsInGenericTypeReference.js b/tests/baselines/reference/errorsInGenericTypeReference.js
index d3d275ff25b..6dd9f62edcb 100644
--- a/tests/baselines/reference/errorsInGenericTypeReference.js
+++ b/tests/baselines/reference/errorsInGenericTypeReference.js
@@ -135,8 +135,7 @@ var testClass6 = (function () {
 var testClass7 = (function (_super) {
     __extends(testClass7, _super);
     function testClass7() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return testClass7;
 }(Foo)); // error: could not find symbol V
diff --git a/tests/baselines/reference/es6ClassTest2.js b/tests/baselines/reference/es6ClassTest2.js
index b3787405ff7..de5657b087e 100644
--- a/tests/baselines/reference/es6ClassTest2.js
+++ b/tests/baselines/reference/es6ClassTest2.js
@@ -314,8 +314,7 @@ var BaseClassWithConstructor = (function () {
 var ChildClassWithoutConstructor = (function (_super) {
     __extends(ChildClassWithoutConstructor, _super);
     function ChildClassWithoutConstructor() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return ChildClassWithoutConstructor;
 }(BaseClassWithConstructor));
diff --git a/tests/baselines/reference/es6ClassTest7.js b/tests/baselines/reference/es6ClassTest7.js
index 6e30a1d7879..f786fce4461 100644
--- a/tests/baselines/reference/es6ClassTest7.js
+++ b/tests/baselines/reference/es6ClassTest7.js
@@ -17,8 +17,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var Bar = (function (_super) {
     __extends(Bar, _super);
     function Bar() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Bar;
 }(M.Foo));
diff --git a/tests/baselines/reference/exportAssignmentOfGenericType1.js b/tests/baselines/reference/exportAssignmentOfGenericType1.js
index 439f74a9c9d..7c1831ecac4 100644
--- a/tests/baselines/reference/exportAssignmentOfGenericType1.js
+++ b/tests/baselines/reference/exportAssignmentOfGenericType1.js
@@ -34,8 +34,7 @@ define(["require", "exports", "exportAssignmentOfGenericType1_0"], function (req
     var M = (function (_super) {
         __extends(M, _super);
         function M() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return M;
     }(q));
diff --git a/tests/baselines/reference/exportDeclarationInInternalModule.js b/tests/baselines/reference/exportDeclarationInInternalModule.js
index b6eec928a07..518c6636947 100644
--- a/tests/baselines/reference/exportDeclarationInInternalModule.js
+++ b/tests/baselines/reference/exportDeclarationInInternalModule.js
@@ -32,8 +32,7 @@ var Bbb = (function () {
 var Aaa = (function (_super) {
     __extends(Aaa, _super);
     function Aaa() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Aaa;
 }(Bbb));
diff --git a/tests/baselines/reference/extBaseClass1.js b/tests/baselines/reference/extBaseClass1.js
index 508eea66500..b20a463338c 100644
--- a/tests/baselines/reference/extBaseClass1.js
+++ b/tests/baselines/reference/extBaseClass1.js
@@ -37,8 +37,7 @@ var M;
     var C = (function (_super) {
         __extends(C, _super);
         function C() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return C;
     }(B));
@@ -49,8 +48,7 @@ var M;
     var C2 = (function (_super) {
         __extends(C2, _super);
         function C2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return C2;
     }(M.B));
@@ -61,8 +59,7 @@ var N;
     var C3 = (function (_super) {
         __extends(C3, _super);
         function C3() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return C3;
     }(M.B));
diff --git a/tests/baselines/reference/extBaseClass2.js b/tests/baselines/reference/extBaseClass2.js
index 14f3d69ef3e..3ab217eb019 100644
--- a/tests/baselines/reference/extBaseClass2.js
+++ b/tests/baselines/reference/extBaseClass2.js
@@ -21,8 +21,7 @@ var N;
     var C4 = (function (_super) {
         __extends(C4, _super);
         function C4() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return C4;
     }(M.B));
@@ -33,8 +32,7 @@ var M;
     var C5 = (function (_super) {
         __extends(C5, _super);
         function C5() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return C5;
     }(B));
diff --git a/tests/baselines/reference/extendAndImplementTheSameBaseType.js b/tests/baselines/reference/extendAndImplementTheSameBaseType.js
index 03bf54db78d..74bbf3a27ac 100644
--- a/tests/baselines/reference/extendAndImplementTheSameBaseType.js
+++ b/tests/baselines/reference/extendAndImplementTheSameBaseType.js
@@ -28,8 +28,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     D.prototype.baz = function () { };
     return D;
diff --git a/tests/baselines/reference/extendAndImplementTheSameBaseType2.js b/tests/baselines/reference/extendAndImplementTheSameBaseType2.js
index 50db54a05e9..fa7963487d5 100644
--- a/tests/baselines/reference/extendAndImplementTheSameBaseType2.js
+++ b/tests/baselines/reference/extendAndImplementTheSameBaseType2.js
@@ -33,8 +33,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     D.prototype.baz = function () { };
     return D;
diff --git a/tests/baselines/reference/extendBaseClassBeforeItsDeclared.js b/tests/baselines/reference/extendBaseClassBeforeItsDeclared.js
index 6cab3a8c7f6..596ab319b2c 100644
--- a/tests/baselines/reference/extendBaseClassBeforeItsDeclared.js
+++ b/tests/baselines/reference/extendBaseClassBeforeItsDeclared.js
@@ -12,8 +12,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var derived = (function (_super) {
     __extends(derived, _super);
     function derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return derived;
 }(base));
diff --git a/tests/baselines/reference/extendClassExpressionFromModule.js b/tests/baselines/reference/extendClassExpressionFromModule.js
index c0cb5d49023..895cdedfaff 100644
--- a/tests/baselines/reference/extendClassExpressionFromModule.js
+++ b/tests/baselines/reference/extendClassExpressionFromModule.js
@@ -31,8 +31,7 @@ var x = foo1;
 var y = (function (_super) {
     __extends(y, _super);
     function y() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return y;
 }(x));
diff --git a/tests/baselines/reference/extendConstructSignatureInInterface.js b/tests/baselines/reference/extendConstructSignatureInInterface.js
index 6985657ced3..4bf92dd0315 100644
--- a/tests/baselines/reference/extendConstructSignatureInInterface.js
+++ b/tests/baselines/reference/extendConstructSignatureInInterface.js
@@ -20,8 +20,7 @@ var CStatic;
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return E;
 }(CStatic));
diff --git a/tests/baselines/reference/extendNonClassSymbol1.js b/tests/baselines/reference/extendNonClassSymbol1.js
index 829b1ae1a32..b23b601bc29 100644
--- a/tests/baselines/reference/extendNonClassSymbol1.js
+++ b/tests/baselines/reference/extendNonClassSymbol1.js
@@ -19,8 +19,7 @@ var x = A;
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(x)); // error, could not find symbol xs
diff --git a/tests/baselines/reference/extendNonClassSymbol2.js b/tests/baselines/reference/extendNonClassSymbol2.js
index 9a2d4fb2adf..78dfaa91827 100644
--- a/tests/baselines/reference/extendNonClassSymbol2.js
+++ b/tests/baselines/reference/extendNonClassSymbol2.js
@@ -18,8 +18,7 @@ var x = new Foo(); // legal, considered a constructor function
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(Foo)); // error, could not find symbol Foo
diff --git a/tests/baselines/reference/extendingClassFromAliasAndUsageInIndexer.js b/tests/baselines/reference/extendingClassFromAliasAndUsageInIndexer.js
index db2fcdbbf36..da081154d8a 100644
--- a/tests/baselines/reference/extendingClassFromAliasAndUsageInIndexer.js
+++ b/tests/baselines/reference/extendingClassFromAliasAndUsageInIndexer.js
@@ -51,8 +51,7 @@ var Backbone = require("./extendingClassFromAliasAndUsageInIndexer_backbone");
 var VisualizationModel = (function (_super) {
     __extends(VisualizationModel, _super);
     function VisualizationModel() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return VisualizationModel;
 }(Backbone.Model));
@@ -68,8 +67,7 @@ var Backbone = require("./extendingClassFromAliasAndUsageInIndexer_backbone");
 var VisualizationModel = (function (_super) {
     __extends(VisualizationModel, _super);
     function VisualizationModel() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return VisualizationModel;
 }(Backbone.Model));
diff --git a/tests/baselines/reference/extendsClauseAlreadySeen.js b/tests/baselines/reference/extendsClauseAlreadySeen.js
index db11c06d782..267cd86eed0 100644
--- a/tests/baselines/reference/extendsClauseAlreadySeen.js
+++ b/tests/baselines/reference/extendsClauseAlreadySeen.js
@@ -20,8 +20,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     D.prototype.baz = function () { };
     return D;
diff --git a/tests/baselines/reference/extendsClauseAlreadySeen2.js b/tests/baselines/reference/extendsClauseAlreadySeen2.js
index f61317c2d50..76fbc3365af 100644
--- a/tests/baselines/reference/extendsClauseAlreadySeen2.js
+++ b/tests/baselines/reference/extendsClauseAlreadySeen2.js
@@ -20,8 +20,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     D.prototype.baz = function () { };
     return D;
diff --git a/tests/baselines/reference/fluentClasses.js b/tests/baselines/reference/fluentClasses.js
index 68a2960b03f..ac44416e133 100644
--- a/tests/baselines/reference/fluentClasses.js
+++ b/tests/baselines/reference/fluentClasses.js
@@ -35,8 +35,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     B.prototype.bar = function () {
         return this;
@@ -46,8 +45,7 @@ var B = (function (_super) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     C.prototype.baz = function () {
         return this;
diff --git a/tests/baselines/reference/for-inStatements.js b/tests/baselines/reference/for-inStatements.js
index 7176a27ebc9..4f52b5e1456 100644
--- a/tests/baselines/reference/for-inStatements.js
+++ b/tests/baselines/reference/for-inStatements.js
@@ -126,8 +126,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     B.prototype.boz = function () {
         for (var x in this.biz()) { }
diff --git a/tests/baselines/reference/for-inStatementsInvalid.js b/tests/baselines/reference/for-inStatementsInvalid.js
index cca8e94dcab..d1181760a36 100644
--- a/tests/baselines/reference/for-inStatementsInvalid.js
+++ b/tests/baselines/reference/for-inStatementsInvalid.js
@@ -107,8 +107,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     B.prototype.boz = function () {
         for (var x in this.biz()) { }
diff --git a/tests/baselines/reference/forStatementsMultipleInvalidDecl.js b/tests/baselines/reference/forStatementsMultipleInvalidDecl.js
index 82910ff0435..3666ad930a6 100644
--- a/tests/baselines/reference/forStatementsMultipleInvalidDecl.js
+++ b/tests/baselines/reference/forStatementsMultipleInvalidDecl.js
@@ -68,8 +68,7 @@ var C = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }(C));
diff --git a/tests/baselines/reference/functionImplementationErrors.js b/tests/baselines/reference/functionImplementationErrors.js
index 465ea54b73f..433418af41d 100644
--- a/tests/baselines/reference/functionImplementationErrors.js
+++ b/tests/baselines/reference/functionImplementationErrors.js
@@ -134,16 +134,14 @@ var AnotherClass = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived1;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/functionImplementations.js b/tests/baselines/reference/functionImplementations.js
index e26e49c1b7a..86636b84a87 100644
--- a/tests/baselines/reference/functionImplementations.js
+++ b/tests/baselines/reference/functionImplementations.js
@@ -236,8 +236,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
@@ -288,8 +287,7 @@ function f6() {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/functionSubtypingOfVarArgs.js b/tests/baselines/reference/functionSubtypingOfVarArgs.js
index c604461f32d..55917962184 100644
--- a/tests/baselines/reference/functionSubtypingOfVarArgs.js
+++ b/tests/baselines/reference/functionSubtypingOfVarArgs.js
@@ -32,8 +32,7 @@ var EventBase = (function () {
 var StringEvent = (function (_super) {
     __extends(StringEvent, _super);
     function StringEvent() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     StringEvent.prototype.add = function (listener) {
         _super.prototype.add.call(this, listener);
diff --git a/tests/baselines/reference/functionSubtypingOfVarArgs2.js b/tests/baselines/reference/functionSubtypingOfVarArgs2.js
index 38a98a3f114..a676316459f 100644
--- a/tests/baselines/reference/functionSubtypingOfVarArgs2.js
+++ b/tests/baselines/reference/functionSubtypingOfVarArgs2.js
@@ -32,8 +32,7 @@ var EventBase = (function () {
 var StringEvent = (function (_super) {
     __extends(StringEvent, _super);
     function StringEvent() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     StringEvent.prototype.add = function (listener) {
         _super.prototype.add.call(this, listener);
diff --git a/tests/baselines/reference/generatedContextualTyping.js b/tests/baselines/reference/generatedContextualTyping.js
index 5c512883a10..2a6911d9cf5 100644
--- a/tests/baselines/reference/generatedContextualTyping.js
+++ b/tests/baselines/reference/generatedContextualTyping.js
@@ -369,16 +369,14 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived1;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/genericBaseClassLiteralProperty.js b/tests/baselines/reference/genericBaseClassLiteralProperty.js
index 25dfb7ae722..a075eff9550 100644
--- a/tests/baselines/reference/genericBaseClassLiteralProperty.js
+++ b/tests/baselines/reference/genericBaseClassLiteralProperty.js
@@ -26,8 +26,7 @@ var BaseClass = (function () {
 var SubClass = (function (_super) {
     __extends(SubClass, _super);
     function SubClass() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     SubClass.prototype.Error = function () {
         var x = this._getValue1();
diff --git a/tests/baselines/reference/genericBaseClassLiteralProperty2.js b/tests/baselines/reference/genericBaseClassLiteralProperty2.js
index e39353b6a7f..2b562742bf7 100644
--- a/tests/baselines/reference/genericBaseClassLiteralProperty2.js
+++ b/tests/baselines/reference/genericBaseClassLiteralProperty2.js
@@ -35,8 +35,7 @@ var BaseCollection2 = (function () {
 var DataView2 = (function (_super) {
     __extends(DataView2, _super);
     function DataView2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     DataView2.prototype.fillItems = function (item) {
         this._itemsByKey['dummy'] = item;
diff --git a/tests/baselines/reference/genericCallWithConstraintsTypeArgumentInference.js b/tests/baselines/reference/genericCallWithConstraintsTypeArgumentInference.js
index 53c02a85113..afef6224ba1 100644
--- a/tests/baselines/reference/genericCallWithConstraintsTypeArgumentInference.js
+++ b/tests/baselines/reference/genericCallWithConstraintsTypeArgumentInference.js
@@ -122,16 +122,14 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived));
diff --git a/tests/baselines/reference/genericCallWithObjectTypeArgs2.js b/tests/baselines/reference/genericCallWithObjectTypeArgs2.js
index 3835a4dd787..7b621b3ffd9 100644
--- a/tests/baselines/reference/genericCallWithObjectTypeArgs2.js
+++ b/tests/baselines/reference/genericCallWithObjectTypeArgs2.js
@@ -46,16 +46,14 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/genericCallWithObjectTypeArgsAndConstraints2.js b/tests/baselines/reference/genericCallWithObjectTypeArgsAndConstraints2.js
index a16f8bcac68..892cda0ee2d 100644
--- a/tests/baselines/reference/genericCallWithObjectTypeArgsAndConstraints2.js
+++ b/tests/baselines/reference/genericCallWithObjectTypeArgsAndConstraints2.js
@@ -54,8 +54,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/genericCallWithObjectTypeArgsAndConstraints3.js b/tests/baselines/reference/genericCallWithObjectTypeArgsAndConstraints3.js
index 410675804af..addfbc756a8 100644
--- a/tests/baselines/reference/genericCallWithObjectTypeArgsAndConstraints3.js
+++ b/tests/baselines/reference/genericCallWithObjectTypeArgsAndConstraints3.js
@@ -52,16 +52,14 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/genericCallbacksAndClassHierarchy.js b/tests/baselines/reference/genericCallbacksAndClassHierarchy.js
index 3fbb7c8a901..c2ad2ba29a3 100644
--- a/tests/baselines/reference/genericCallbacksAndClassHierarchy.js
+++ b/tests/baselines/reference/genericCallbacksAndClassHierarchy.js
@@ -46,8 +46,7 @@ var M;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(C1));
diff --git a/tests/baselines/reference/genericClassExpressionInFunction.js b/tests/baselines/reference/genericClassExpressionInFunction.js
index d14b70b6312..dc574dedb00 100644
--- a/tests/baselines/reference/genericClassExpressionInFunction.js
+++ b/tests/baselines/reference/genericClassExpressionInFunction.js
@@ -47,8 +47,7 @@ function B1() {
     return (function (_super) {
         __extends(class_1, _super);
         function class_1() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return class_1;
     }(A));
@@ -58,8 +57,7 @@ var B2 = (function () {
         this.anon = (function (_super) {
             __extends(class_2, _super);
             function class_2() {
-                var _this = _super.apply(this, arguments) || this;
-                return _this;
+                return _super.apply(this, arguments) || this;
             }
             return class_2;
         }(A));
@@ -70,8 +68,7 @@ function B3() {
     return (function (_super) {
         __extends(Inner, _super);
         function Inner() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Inner;
     }(A));
@@ -80,16 +77,14 @@ function B3() {
 var K = (function (_super) {
     __extends(K, _super);
     function K() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return K;
 }(B1()));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }((new B2().anon)));
@@ -97,8 +92,7 @@ var b3Number = B3();
 var S = (function (_super) {
     __extends(S, _super);
     function S() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return S;
 }(b3Number));
diff --git a/tests/baselines/reference/genericClassInheritsConstructorFromNonGenericClass.js b/tests/baselines/reference/genericClassInheritsConstructorFromNonGenericClass.js
index a6c14b9ba0f..1f3a6e17f14 100644
--- a/tests/baselines/reference/genericClassInheritsConstructorFromNonGenericClass.js
+++ b/tests/baselines/reference/genericClassInheritsConstructorFromNonGenericClass.js
@@ -14,16 +14,14 @@ var __extends = (this && this.__extends) || function (d, b) {
 var A = (function (_super) {
     __extends(A, _super);
     function A() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return A;
 }(B));
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(C));
diff --git a/tests/baselines/reference/genericClassStaticMethod.js b/tests/baselines/reference/genericClassStaticMethod.js
index 2124f414172..4609e3bc9db 100644
--- a/tests/baselines/reference/genericClassStaticMethod.js
+++ b/tests/baselines/reference/genericClassStaticMethod.js
@@ -26,8 +26,7 @@ var Foo = (function () {
 var Bar = (function (_super) {
     __extends(Bar, _super);
     function Bar() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Bar.getFoo = function () {
     };
diff --git a/tests/baselines/reference/genericClasses3.js b/tests/baselines/reference/genericClasses3.js
index 6f10b979c4a..5371e2479aa 100644
--- a/tests/baselines/reference/genericClasses3.js
+++ b/tests/baselines/reference/genericClasses3.js
@@ -31,8 +31,7 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(B));
diff --git a/tests/baselines/reference/genericDerivedTypeWithSpecializedBase.js b/tests/baselines/reference/genericDerivedTypeWithSpecializedBase.js
index 454bc77ae5b..1b455073196 100644
--- a/tests/baselines/reference/genericDerivedTypeWithSpecializedBase.js
+++ b/tests/baselines/reference/genericDerivedTypeWithSpecializedBase.js
@@ -26,8 +26,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/genericDerivedTypeWithSpecializedBase2.js b/tests/baselines/reference/genericDerivedTypeWithSpecializedBase2.js
index 26749718d43..0abd655e1da 100644
--- a/tests/baselines/reference/genericDerivedTypeWithSpecializedBase2.js
+++ b/tests/baselines/reference/genericDerivedTypeWithSpecializedBase2.js
@@ -26,8 +26,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/genericInheritedDefaultConstructors.js b/tests/baselines/reference/genericInheritedDefaultConstructors.js
index e7c32cbe73f..059a3213b7a 100644
--- a/tests/baselines/reference/genericInheritedDefaultConstructors.js
+++ b/tests/baselines/reference/genericInheritedDefaultConstructors.js
@@ -24,8 +24,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/genericPrototypeProperty2.js b/tests/baselines/reference/genericPrototypeProperty2.js
index ccaf6fa8807..eac025cce9b 100644
--- a/tests/baselines/reference/genericPrototypeProperty2.js
+++ b/tests/baselines/reference/genericPrototypeProperty2.js
@@ -29,8 +29,7 @@ var BaseEvent = (function () {
 var MyEvent = (function (_super) {
     __extends(MyEvent, _super);
     function MyEvent() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return MyEvent;
 }(BaseEvent));
@@ -42,8 +41,7 @@ var BaseEventWrapper = (function () {
 var MyEventWrapper = (function (_super) {
     __extends(MyEventWrapper, _super);
     function MyEventWrapper() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return MyEventWrapper;
 }(BaseEventWrapper));
diff --git a/tests/baselines/reference/genericPrototypeProperty3.js b/tests/baselines/reference/genericPrototypeProperty3.js
index 85658593705..9e3ede0019d 100644
--- a/tests/baselines/reference/genericPrototypeProperty3.js
+++ b/tests/baselines/reference/genericPrototypeProperty3.js
@@ -28,8 +28,7 @@ var BaseEvent = (function () {
 var MyEvent = (function (_super) {
     __extends(MyEvent, _super);
     function MyEvent() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return MyEvent;
 }(BaseEvent));
@@ -41,8 +40,7 @@ var BaseEventWrapper = (function () {
 var MyEventWrapper = (function (_super) {
     __extends(MyEventWrapper, _super);
     function MyEventWrapper() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return MyEventWrapper;
 }(BaseEventWrapper));
diff --git a/tests/baselines/reference/genericRecursiveImplicitConstructorErrors2.js b/tests/baselines/reference/genericRecursiveImplicitConstructorErrors2.js
index e567e2a8042..6d65ee5531b 100644
--- a/tests/baselines/reference/genericRecursiveImplicitConstructorErrors2.js
+++ b/tests/baselines/reference/genericRecursiveImplicitConstructorErrors2.js
@@ -57,8 +57,7 @@ var TypeScript2;
     var PullTypeSymbol = (function (_super) {
         __extends(PullTypeSymbol, _super);
         function PullTypeSymbol() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return PullTypeSymbol;
     }(PullSymbol));
diff --git a/tests/baselines/reference/genericTypeAssertions2.js b/tests/baselines/reference/genericTypeAssertions2.js
index 31d2b3976db..687d593f01e 100644
--- a/tests/baselines/reference/genericTypeAssertions2.js
+++ b/tests/baselines/reference/genericTypeAssertions2.js
@@ -28,8 +28,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     B.prototype.bar = function () {
         return null;
diff --git a/tests/baselines/reference/genericTypeAssertions4.js b/tests/baselines/reference/genericTypeAssertions4.js
index 41a187edb6a..50dbe5debbd 100644
--- a/tests/baselines/reference/genericTypeAssertions4.js
+++ b/tests/baselines/reference/genericTypeAssertions4.js
@@ -40,8 +40,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     B.prototype.bar = function () { return 1; };
     return B;
@@ -49,8 +48,7 @@ var B = (function (_super) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     C.prototype.baz = function () { return 1; };
     return C;
diff --git a/tests/baselines/reference/genericTypeAssertions6.js b/tests/baselines/reference/genericTypeAssertions6.js
index b776668f2e2..7bbd7351f1d 100644
--- a/tests/baselines/reference/genericTypeAssertions6.js
+++ b/tests/baselines/reference/genericTypeAssertions6.js
@@ -44,8 +44,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     B.prototype.g = function (x) {
         var a = x;
diff --git a/tests/baselines/reference/genericTypeReferenceWithoutTypeArgument.js b/tests/baselines/reference/genericTypeReferenceWithoutTypeArgument.js
index 39468204a5a..cf19feede34 100644
--- a/tests/baselines/reference/genericTypeReferenceWithoutTypeArgument.js
+++ b/tests/baselines/reference/genericTypeReferenceWithoutTypeArgument.js
@@ -60,8 +60,7 @@ var g = function f(x) { var y; return y; };
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(C));
@@ -77,8 +76,7 @@ var M;
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D2;
 }(M.E));
diff --git a/tests/baselines/reference/genericTypeReferenceWithoutTypeArgument2.js b/tests/baselines/reference/genericTypeReferenceWithoutTypeArgument2.js
index a41d459b445..973ee231762 100644
--- a/tests/baselines/reference/genericTypeReferenceWithoutTypeArgument2.js
+++ b/tests/baselines/reference/genericTypeReferenceWithoutTypeArgument2.js
@@ -55,16 +55,14 @@ var g = function f(x) { var y; return y; };
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(I));
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D2;
 }(M.C));
diff --git a/tests/baselines/reference/genericWithIndexerOfTypeParameterType2.js b/tests/baselines/reference/genericWithIndexerOfTypeParameterType2.js
index c0498b351e1..d6fb98b67ca 100644
--- a/tests/baselines/reference/genericWithIndexerOfTypeParameterType2.js
+++ b/tests/baselines/reference/genericWithIndexerOfTypeParameterType2.js
@@ -31,8 +31,7 @@ define(["require", "exports"], function (require, exports) {
     var List = (function (_super) {
         __extends(List, _super);
         function List() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         List.prototype.Bar = function () { };
         return List;
@@ -47,8 +46,7 @@ define(["require", "exports"], function (require, exports) {
     var ListItem = (function (_super) {
         __extends(ListItem, _super);
         function ListItem() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return ListItem;
     }(CollectionItem));
diff --git a/tests/baselines/reference/heterogeneousArrayLiterals.js b/tests/baselines/reference/heterogeneousArrayLiterals.js
index e3c50cfa8f7..60a8976722d 100644
--- a/tests/baselines/reference/heterogeneousArrayLiterals.js
+++ b/tests/baselines/reference/heterogeneousArrayLiterals.js
@@ -160,16 +160,14 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/ifDoWhileStatements.js b/tests/baselines/reference/ifDoWhileStatements.js
index af1e3be18ff..483370bee5c 100644
--- a/tests/baselines/reference/ifDoWhileStatements.js
+++ b/tests/baselines/reference/ifDoWhileStatements.js
@@ -177,8 +177,7 @@ var C = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }(C));
diff --git a/tests/baselines/reference/implementClausePrecedingExtends.js b/tests/baselines/reference/implementClausePrecedingExtends.js
index 0dfc867a2f7..df725cde43a 100644
--- a/tests/baselines/reference/implementClausePrecedingExtends.js
+++ b/tests/baselines/reference/implementClausePrecedingExtends.js
@@ -16,8 +16,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/implementingAnInterfaceExtendingClassWithPrivates2.js b/tests/baselines/reference/implementingAnInterfaceExtendingClassWithPrivates2.js
index 033d6150194..a5a5e02c156 100644
--- a/tests/baselines/reference/implementingAnInterfaceExtendingClassWithPrivates2.js
+++ b/tests/baselines/reference/implementingAnInterfaceExtendingClassWithPrivates2.js
@@ -99,24 +99,21 @@ var Foo = (function () {
 var Bar = (function (_super) {
     __extends(Bar, _super);
     function Bar() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Bar;
 }(Foo));
 var Bar2 = (function (_super) {
     __extends(Bar2, _super);
     function Bar2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Bar2;
 }(Foo));
 var Bar3 = (function (_super) {
     __extends(Bar3, _super);
     function Bar3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Bar3;
 }(Foo));
@@ -131,32 +128,28 @@ var M;
     var Baz = (function (_super) {
         __extends(Baz, _super);
         function Baz() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Baz;
     }(Foo));
     var Bar = (function (_super) {
         __extends(Bar, _super);
         function Bar() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Bar;
     }(Foo));
     var Bar2 = (function (_super) {
         __extends(Bar2, _super);
         function Bar2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Bar2;
     }(Foo));
     var Bar3 = (function (_super) {
         __extends(Bar3, _super);
         function Bar3() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Bar3;
     }(Foo));
@@ -172,16 +165,14 @@ var M2;
     var Baz = (function (_super) {
         __extends(Baz, _super);
         function Baz() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Baz;
     }(Foo));
     var Bar = (function (_super) {
         __extends(Bar, _super);
         function Bar() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Bar;
     }(Foo));
@@ -192,16 +183,14 @@ var M2;
     var Bar2 = (function (_super) {
         __extends(Bar2, _super);
         function Bar2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Bar2;
     }(Foo));
     var Bar3 = (function (_super) {
         __extends(Bar3, _super);
         function Bar3() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Bar3;
     }(Foo));
diff --git a/tests/baselines/reference/implementingAnInterfaceExtendingClassWithProtecteds.js b/tests/baselines/reference/implementingAnInterfaceExtendingClassWithProtecteds.js
index 78cfb6b51b9..d0f74847141 100644
--- a/tests/baselines/reference/implementingAnInterfaceExtendingClassWithProtecteds.js
+++ b/tests/baselines/reference/implementingAnInterfaceExtendingClassWithProtecteds.js
@@ -75,32 +75,28 @@ var Bar4 = (function () {
 var Bar5 = (function (_super) {
     __extends(Bar5, _super);
     function Bar5() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Bar5;
 }(Foo));
 var Bar6 = (function (_super) {
     __extends(Bar6, _super);
     function Bar6() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Bar6;
 }(Foo));
 var Bar7 = (function (_super) {
     __extends(Bar7, _super);
     function Bar7() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Bar7;
 }(Foo));
 var Bar8 = (function (_super) {
     __extends(Bar8, _super);
     function Bar8() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Bar8;
 }(Foo));
diff --git a/tests/baselines/reference/importAsBaseClass.js b/tests/baselines/reference/importAsBaseClass.js
index d9f40f83051..b4f45cac806 100644
--- a/tests/baselines/reference/importAsBaseClass.js
+++ b/tests/baselines/reference/importAsBaseClass.js
@@ -30,8 +30,7 @@ var Greeter = require("./importAsBaseClass_0");
 var Hello = (function (_super) {
     __extends(Hello, _super);
     function Hello() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Hello;
 }(Greeter));
diff --git a/tests/baselines/reference/importHelpers.js b/tests/baselines/reference/importHelpers.js
index 6641ef9d212..ae4d3127010 100644
--- a/tests/baselines/reference/importHelpers.js
+++ b/tests/baselines/reference/importHelpers.js
@@ -45,8 +45,7 @@ exports.A = A;
 var B = (function (_super) {
     tslib_1.__extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
@@ -94,8 +93,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/importHelpersAmd.js b/tests/baselines/reference/importHelpersAmd.js
index 89fab70bdba..fea93840fa9 100644
--- a/tests/baselines/reference/importHelpersAmd.js
+++ b/tests/baselines/reference/importHelpersAmd.js
@@ -32,8 +32,7 @@ define(["require", "exports", "tslib", "./a"], function (require, exports, tslib
     var B = (function (_super) {
         tslib_1.__extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(a_1.A));
diff --git a/tests/baselines/reference/importHelpersInIsolatedModules.js b/tests/baselines/reference/importHelpersInIsolatedModules.js
index 2a97d3d2d87..28c00f97554 100644
--- a/tests/baselines/reference/importHelpersInIsolatedModules.js
+++ b/tests/baselines/reference/importHelpersInIsolatedModules.js
@@ -45,8 +45,7 @@ exports.A = A;
 var B = (function (_super) {
     tslib_1.__extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
@@ -79,8 +78,7 @@ var A = (function () {
 var B = (function (_super) {
     tslib_1.__extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/importHelpersNoHelpers.js b/tests/baselines/reference/importHelpersNoHelpers.js
index d5f8db60f97..e22d1f4353d 100644
--- a/tests/baselines/reference/importHelpersNoHelpers.js
+++ b/tests/baselines/reference/importHelpersNoHelpers.js
@@ -39,8 +39,7 @@ exports.A = A;
 var B = (function (_super) {
     tslib_1.__extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
@@ -88,8 +87,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/importHelpersNoModule.js b/tests/baselines/reference/importHelpersNoModule.js
index 5891922f9f2..41df9710f33 100644
--- a/tests/baselines/reference/importHelpersNoModule.js
+++ b/tests/baselines/reference/importHelpersNoModule.js
@@ -37,8 +37,7 @@ exports.A = A;
 var B = (function (_super) {
     tslib_1.__extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
@@ -86,8 +85,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/importHelpersOutFile.js b/tests/baselines/reference/importHelpersOutFile.js
index b4c2040aa71..a45f6285782 100644
--- a/tests/baselines/reference/importHelpersOutFile.js
+++ b/tests/baselines/reference/importHelpersOutFile.js
@@ -35,8 +35,7 @@ define("b", ["require", "exports", "tslib", "a"], function (require, exports, ts
     var B = (function (_super) {
         tslib_1.__extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(a_1.A));
@@ -47,8 +46,7 @@ define("c", ["require", "exports", "tslib", "a"], function (require, exports, ts
     var C = (function (_super) {
         tslib_2.__extends(C, _super);
         function C() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return C;
     }(a_2.A));
diff --git a/tests/baselines/reference/importHelpersSystem.js b/tests/baselines/reference/importHelpersSystem.js
index 552bd0ed404..20f2d299c52 100644
--- a/tests/baselines/reference/importHelpersSystem.js
+++ b/tests/baselines/reference/importHelpersSystem.js
@@ -51,8 +51,7 @@ System.register(["tslib", "./a"], function (exports_1, context_1) {
             B = (function (_super) {
                 tslib_1.__extends(B, _super);
                 function B() {
-                    var _this = _super.apply(this, arguments) || this;
-                    return _this;
+                    return _super.apply(this, arguments) || this;
                 }
                 return B;
             }(a_1.A));
diff --git a/tests/baselines/reference/importShadowsGlobalName.js b/tests/baselines/reference/importShadowsGlobalName.js
index b4950b039f3..34cc0604e7a 100644
--- a/tests/baselines/reference/importShadowsGlobalName.js
+++ b/tests/baselines/reference/importShadowsGlobalName.js
@@ -31,8 +31,7 @@ define(["require", "exports", "Foo"], function (require, exports, Error) {
     var Bar = (function (_super) {
         __extends(Bar, _super);
         function Bar() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Bar;
     }(Error));
diff --git a/tests/baselines/reference/importUsedInExtendsList1.js b/tests/baselines/reference/importUsedInExtendsList1.js
index 956e20a1045..a40c3a51a78 100644
--- a/tests/baselines/reference/importUsedInExtendsList1.js
+++ b/tests/baselines/reference/importUsedInExtendsList1.js
@@ -31,8 +31,7 @@ var foo = require("./importUsedInExtendsList1_require");
 var Sub = (function (_super) {
     __extends(Sub, _super);
     function Sub() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Sub;
 }(foo.Super));
diff --git a/tests/baselines/reference/indexerConstraints2.js b/tests/baselines/reference/indexerConstraints2.js
index c8b910abb2d..d7357f021d0 100644
--- a/tests/baselines/reference/indexerConstraints2.js
+++ b/tests/baselines/reference/indexerConstraints2.js
@@ -42,8 +42,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
@@ -56,8 +55,7 @@ var F = (function () {
 var G = (function (_super) {
     __extends(G, _super);
     function G() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return G;
 }(F));
@@ -70,8 +68,7 @@ var H = (function () {
 var I = (function (_super) {
     __extends(I, _super);
     function I() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return I;
 }(H));
@@ -84,8 +81,7 @@ var J = (function () {
 var K = (function (_super) {
     __extends(K, _super);
     function K() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return K;
 }(J));
diff --git a/tests/baselines/reference/indirectSelfReference.js b/tests/baselines/reference/indirectSelfReference.js
index c1c77ec5fc9..2f4f37b9b53 100644
--- a/tests/baselines/reference/indirectSelfReference.js
+++ b/tests/baselines/reference/indirectSelfReference.js
@@ -11,16 +11,14 @@ var __extends = (this && this.__extends) || function (d, b) {
 var a = (function (_super) {
     __extends(a, _super);
     function a() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return a;
 }(b));
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return b;
 }(a));
diff --git a/tests/baselines/reference/indirectSelfReferenceGeneric.js b/tests/baselines/reference/indirectSelfReferenceGeneric.js
index 366ad1f0af5..9171bb0eeb6 100644
--- a/tests/baselines/reference/indirectSelfReferenceGeneric.js
+++ b/tests/baselines/reference/indirectSelfReferenceGeneric.js
@@ -11,16 +11,14 @@ var __extends = (this && this.__extends) || function (d, b) {
 var a = (function (_super) {
     __extends(a, _super);
     function a() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return a;
 }(b));
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return b;
 }(a));
diff --git a/tests/baselines/reference/infinitelyExpandingTypesNonGenericBase.js b/tests/baselines/reference/infinitelyExpandingTypesNonGenericBase.js
index 9b145b55d04..ad1a063bfb0 100644
--- a/tests/baselines/reference/infinitelyExpandingTypesNonGenericBase.js
+++ b/tests/baselines/reference/infinitelyExpandingTypesNonGenericBase.js
@@ -43,8 +43,7 @@ var Base = (function () {
 var A = (function (_super) {
     __extends(A, _super);
     function A() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return A;
 }(Base));
diff --git a/tests/baselines/reference/inheritFromGenericTypeParameter.js b/tests/baselines/reference/inheritFromGenericTypeParameter.js
index 5db269f7c58..40e6abd3e53 100644
--- a/tests/baselines/reference/inheritFromGenericTypeParameter.js
+++ b/tests/baselines/reference/inheritFromGenericTypeParameter.js
@@ -11,8 +11,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(T));
diff --git a/tests/baselines/reference/inheritSameNamePrivatePropertiesFromSameOrigin.js b/tests/baselines/reference/inheritSameNamePrivatePropertiesFromSameOrigin.js
index 7f3e872245b..a0874eb1c72 100644
--- a/tests/baselines/reference/inheritSameNamePrivatePropertiesFromSameOrigin.js
+++ b/tests/baselines/reference/inheritSameNamePrivatePropertiesFromSameOrigin.js
@@ -24,16 +24,14 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(B));
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }(B));
diff --git a/tests/baselines/reference/inheritance.js b/tests/baselines/reference/inheritance.js
index c4acea22260..cbfef2d3382 100644
--- a/tests/baselines/reference/inheritance.js
+++ b/tests/baselines/reference/inheritance.js
@@ -53,16 +53,14 @@ var B2 = (function () {
 var D1 = (function (_super) {
     __extends(D1, _super);
     function D1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D1;
 }(B1));
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D2;
 }(B2));
@@ -74,8 +72,7 @@ var N = (function () {
 var ND = (function (_super) {
     __extends(ND, _super);
     function ND() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return ND;
 }(N));
@@ -89,8 +86,7 @@ var Good = (function () {
 var Baad = (function (_super) {
     __extends(Baad, _super);
     function Baad() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Baad.prototype.f = function () { return 0; };
     Baad.prototype.g = function (n) { return 0; };
diff --git a/tests/baselines/reference/inheritance1.js b/tests/baselines/reference/inheritance1.js
index f555d5bf694..86de0b76350 100644
--- a/tests/baselines/reference/inheritance1.js
+++ b/tests/baselines/reference/inheritance1.js
@@ -75,8 +75,7 @@ var Control = (function () {
 var Button = (function (_super) {
     __extends(Button, _super);
     function Button() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Button.prototype.select = function () { };
     return Button;
@@ -84,8 +83,7 @@ var Button = (function (_super) {
 var TextBox = (function (_super) {
     __extends(TextBox, _super);
     function TextBox() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     TextBox.prototype.select = function () { };
     return TextBox;
@@ -93,16 +91,14 @@ var TextBox = (function (_super) {
 var ImageBase = (function (_super) {
     __extends(ImageBase, _super);
     function ImageBase() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return ImageBase;
 }(Control));
 var Image1 = (function (_super) {
     __extends(Image1, _super);
     function Image1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Image1;
 }(Control));
diff --git a/tests/baselines/reference/inheritanceGrandParentPrivateMemberCollision.js b/tests/baselines/reference/inheritanceGrandParentPrivateMemberCollision.js
index 2ed366d7b8a..57a9c897583 100644
--- a/tests/baselines/reference/inheritanceGrandParentPrivateMemberCollision.js
+++ b/tests/baselines/reference/inheritanceGrandParentPrivateMemberCollision.js
@@ -25,16 +25,14 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     C.prototype.myMethod = function () { };
     return C;
diff --git a/tests/baselines/reference/inheritanceGrandParentPrivateMemberCollisionWithPublicMember.js b/tests/baselines/reference/inheritanceGrandParentPrivateMemberCollisionWithPublicMember.js
index 369c6b20a14..83c5aa3e4cd 100644
--- a/tests/baselines/reference/inheritanceGrandParentPrivateMemberCollisionWithPublicMember.js
+++ b/tests/baselines/reference/inheritanceGrandParentPrivateMemberCollisionWithPublicMember.js
@@ -25,16 +25,14 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     C.prototype.myMethod = function () { };
     return C;
diff --git a/tests/baselines/reference/inheritanceGrandParentPublicMemberCollisionWithPrivateMember.js b/tests/baselines/reference/inheritanceGrandParentPublicMemberCollisionWithPrivateMember.js
index d884364d95c..b11b6e318a7 100644
--- a/tests/baselines/reference/inheritanceGrandParentPublicMemberCollisionWithPrivateMember.js
+++ b/tests/baselines/reference/inheritanceGrandParentPublicMemberCollisionWithPrivateMember.js
@@ -25,16 +25,14 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     C.prototype.myMethod = function () { };
     return C;
diff --git a/tests/baselines/reference/inheritanceMemberAccessorOverridingAccessor.js b/tests/baselines/reference/inheritanceMemberAccessorOverridingAccessor.js
index c1289f99a78..09ea08899d9 100644
--- a/tests/baselines/reference/inheritanceMemberAccessorOverridingAccessor.js
+++ b/tests/baselines/reference/inheritanceMemberAccessorOverridingAccessor.js
@@ -40,8 +40,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Object.defineProperty(b.prototype, "x", {
         get: function () {
diff --git a/tests/baselines/reference/inheritanceMemberAccessorOverridingMethod.js b/tests/baselines/reference/inheritanceMemberAccessorOverridingMethod.js
index 665b547154d..59d2abdaab2 100644
--- a/tests/baselines/reference/inheritanceMemberAccessorOverridingMethod.js
+++ b/tests/baselines/reference/inheritanceMemberAccessorOverridingMethod.js
@@ -31,8 +31,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Object.defineProperty(b.prototype, "x", {
         get: function () {
diff --git a/tests/baselines/reference/inheritanceMemberAccessorOverridingProperty.js b/tests/baselines/reference/inheritanceMemberAccessorOverridingProperty.js
index a9a92003542..98a95747a8e 100644
--- a/tests/baselines/reference/inheritanceMemberAccessorOverridingProperty.js
+++ b/tests/baselines/reference/inheritanceMemberAccessorOverridingProperty.js
@@ -26,8 +26,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Object.defineProperty(b.prototype, "x", {
         get: function () {
diff --git a/tests/baselines/reference/inheritanceMemberFuncOverridingAccessor.js b/tests/baselines/reference/inheritanceMemberFuncOverridingAccessor.js
index 17541ee163d..0d54e5d42fa 100644
--- a/tests/baselines/reference/inheritanceMemberFuncOverridingAccessor.js
+++ b/tests/baselines/reference/inheritanceMemberFuncOverridingAccessor.js
@@ -37,8 +37,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     b.prototype.x = function () {
         return "20";
diff --git a/tests/baselines/reference/inheritanceMemberFuncOverridingMethod.js b/tests/baselines/reference/inheritanceMemberFuncOverridingMethod.js
index a154d0426a9..9af25c6fdb8 100644
--- a/tests/baselines/reference/inheritanceMemberFuncOverridingMethod.js
+++ b/tests/baselines/reference/inheritanceMemberFuncOverridingMethod.js
@@ -28,8 +28,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     b.prototype.x = function () {
         return "20";
diff --git a/tests/baselines/reference/inheritanceMemberFuncOverridingProperty.js b/tests/baselines/reference/inheritanceMemberFuncOverridingProperty.js
index be10895642e..5c77ce08101 100644
--- a/tests/baselines/reference/inheritanceMemberFuncOverridingProperty.js
+++ b/tests/baselines/reference/inheritanceMemberFuncOverridingProperty.js
@@ -23,8 +23,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     b.prototype.x = function () {
         return "20";
diff --git a/tests/baselines/reference/inheritanceMemberPropertyOverridingAccessor.js b/tests/baselines/reference/inheritanceMemberPropertyOverridingAccessor.js
index 6895077abda..82c7a94d17c 100644
--- a/tests/baselines/reference/inheritanceMemberPropertyOverridingAccessor.js
+++ b/tests/baselines/reference/inheritanceMemberPropertyOverridingAccessor.js
@@ -37,8 +37,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return b;
 }(a));
diff --git a/tests/baselines/reference/inheritanceMemberPropertyOverridingMethod.js b/tests/baselines/reference/inheritanceMemberPropertyOverridingMethod.js
index 00c1093053b..e6929218e63 100644
--- a/tests/baselines/reference/inheritanceMemberPropertyOverridingMethod.js
+++ b/tests/baselines/reference/inheritanceMemberPropertyOverridingMethod.js
@@ -26,8 +26,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return b;
 }(a));
diff --git a/tests/baselines/reference/inheritanceMemberPropertyOverridingProperty.js b/tests/baselines/reference/inheritanceMemberPropertyOverridingProperty.js
index 6cbb7ae7e8c..85764cddc52 100644
--- a/tests/baselines/reference/inheritanceMemberPropertyOverridingProperty.js
+++ b/tests/baselines/reference/inheritanceMemberPropertyOverridingProperty.js
@@ -21,8 +21,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return b;
 }(a));
diff --git a/tests/baselines/reference/inheritanceOfGenericConstructorMethod1.js b/tests/baselines/reference/inheritanceOfGenericConstructorMethod1.js
index 370e27514c1..28fe8144509 100644
--- a/tests/baselines/reference/inheritanceOfGenericConstructorMethod1.js
+++ b/tests/baselines/reference/inheritanceOfGenericConstructorMethod1.js
@@ -21,8 +21,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/inheritanceOfGenericConstructorMethod2.js b/tests/baselines/reference/inheritanceOfGenericConstructorMethod2.js
index a61b6bafabd..0cc71e168f4 100644
--- a/tests/baselines/reference/inheritanceOfGenericConstructorMethod2.js
+++ b/tests/baselines/reference/inheritanceOfGenericConstructorMethod2.js
@@ -40,8 +40,7 @@ var N;
     var D1 = (function (_super) {
         __extends(D1, _super);
         function D1() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D1;
     }(M.C1));
@@ -49,8 +48,7 @@ var N;
     var D2 = (function (_super) {
         __extends(D2, _super);
         function D2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D2;
     }(M.C2));
diff --git a/tests/baselines/reference/inheritanceStaticAccessorOverridingAccessor.js b/tests/baselines/reference/inheritanceStaticAccessorOverridingAccessor.js
index 9f71208e5db..bb91ee5f9ea 100644
--- a/tests/baselines/reference/inheritanceStaticAccessorOverridingAccessor.js
+++ b/tests/baselines/reference/inheritanceStaticAccessorOverridingAccessor.js
@@ -40,8 +40,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Object.defineProperty(b, "x", {
         get: function () {
diff --git a/tests/baselines/reference/inheritanceStaticAccessorOverridingMethod.js b/tests/baselines/reference/inheritanceStaticAccessorOverridingMethod.js
index 2e0c3dc90d0..363852a84bf 100644
--- a/tests/baselines/reference/inheritanceStaticAccessorOverridingMethod.js
+++ b/tests/baselines/reference/inheritanceStaticAccessorOverridingMethod.js
@@ -31,8 +31,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Object.defineProperty(b, "x", {
         get: function () {
diff --git a/tests/baselines/reference/inheritanceStaticAccessorOverridingProperty.js b/tests/baselines/reference/inheritanceStaticAccessorOverridingProperty.js
index 95bf94572b1..ba8df7a5f0b 100644
--- a/tests/baselines/reference/inheritanceStaticAccessorOverridingProperty.js
+++ b/tests/baselines/reference/inheritanceStaticAccessorOverridingProperty.js
@@ -26,8 +26,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Object.defineProperty(b, "x", {
         get: function () {
diff --git a/tests/baselines/reference/inheritanceStaticFuncOverridingAccessor.js b/tests/baselines/reference/inheritanceStaticFuncOverridingAccessor.js
index 25d75bea5af..e464029fba5 100644
--- a/tests/baselines/reference/inheritanceStaticFuncOverridingAccessor.js
+++ b/tests/baselines/reference/inheritanceStaticFuncOverridingAccessor.js
@@ -37,8 +37,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     b.x = function () {
         return "20";
diff --git a/tests/baselines/reference/inheritanceStaticFuncOverridingAccessorOfFuncType.js b/tests/baselines/reference/inheritanceStaticFuncOverridingAccessorOfFuncType.js
index 5c39c10e738..cc825cfa9b5 100644
--- a/tests/baselines/reference/inheritanceStaticFuncOverridingAccessorOfFuncType.js
+++ b/tests/baselines/reference/inheritanceStaticFuncOverridingAccessorOfFuncType.js
@@ -32,8 +32,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     b.x = function () {
         return "20";
diff --git a/tests/baselines/reference/inheritanceStaticFuncOverridingMethod.js b/tests/baselines/reference/inheritanceStaticFuncOverridingMethod.js
index c37caf8d53c..466c65fa7d5 100644
--- a/tests/baselines/reference/inheritanceStaticFuncOverridingMethod.js
+++ b/tests/baselines/reference/inheritanceStaticFuncOverridingMethod.js
@@ -28,8 +28,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     b.x = function () {
         return "20";
diff --git a/tests/baselines/reference/inheritanceStaticFuncOverridingProperty.js b/tests/baselines/reference/inheritanceStaticFuncOverridingProperty.js
index eb185d56d0b..dfc0ce2c13f 100644
--- a/tests/baselines/reference/inheritanceStaticFuncOverridingProperty.js
+++ b/tests/baselines/reference/inheritanceStaticFuncOverridingProperty.js
@@ -23,8 +23,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     b.x = function () {
         return "20";
diff --git a/tests/baselines/reference/inheritanceStaticFuncOverridingPropertyOfFuncType.js b/tests/baselines/reference/inheritanceStaticFuncOverridingPropertyOfFuncType.js
index 0779cc10d37..da7850f2071 100644
--- a/tests/baselines/reference/inheritanceStaticFuncOverridingPropertyOfFuncType.js
+++ b/tests/baselines/reference/inheritanceStaticFuncOverridingPropertyOfFuncType.js
@@ -23,8 +23,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     b.x = function () {
         return "20";
diff --git a/tests/baselines/reference/inheritanceStaticFunctionOverridingInstanceProperty.js b/tests/baselines/reference/inheritanceStaticFunctionOverridingInstanceProperty.js
index 4934947233f..d5916a9d452 100644
--- a/tests/baselines/reference/inheritanceStaticFunctionOverridingInstanceProperty.js
+++ b/tests/baselines/reference/inheritanceStaticFunctionOverridingInstanceProperty.js
@@ -23,8 +23,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     b.x = function () {
         return new b().x;
diff --git a/tests/baselines/reference/inheritanceStaticMembersCompatible.js b/tests/baselines/reference/inheritanceStaticMembersCompatible.js
index 27a65d513fd..b4cae99b64b 100644
--- a/tests/baselines/reference/inheritanceStaticMembersCompatible.js
+++ b/tests/baselines/reference/inheritanceStaticMembersCompatible.js
@@ -21,8 +21,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return b;
 }(a));
diff --git a/tests/baselines/reference/inheritanceStaticMembersIncompatible.js b/tests/baselines/reference/inheritanceStaticMembersIncompatible.js
index 7cfafdf1f9d..38c637dd8d1 100644
--- a/tests/baselines/reference/inheritanceStaticMembersIncompatible.js
+++ b/tests/baselines/reference/inheritanceStaticMembersIncompatible.js
@@ -21,8 +21,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return b;
 }(a));
diff --git a/tests/baselines/reference/inheritanceStaticPropertyOverridingAccessor.js b/tests/baselines/reference/inheritanceStaticPropertyOverridingAccessor.js
index 1840a7829e8..49dc86fc500 100644
--- a/tests/baselines/reference/inheritanceStaticPropertyOverridingAccessor.js
+++ b/tests/baselines/reference/inheritanceStaticPropertyOverridingAccessor.js
@@ -36,8 +36,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return b;
 }(a));
diff --git a/tests/baselines/reference/inheritanceStaticPropertyOverridingMethod.js b/tests/baselines/reference/inheritanceStaticPropertyOverridingMethod.js
index 8e498273b86..bcd63537540 100644
--- a/tests/baselines/reference/inheritanceStaticPropertyOverridingMethod.js
+++ b/tests/baselines/reference/inheritanceStaticPropertyOverridingMethod.js
@@ -26,8 +26,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return b;
 }(a));
diff --git a/tests/baselines/reference/inheritanceStaticPropertyOverridingProperty.js b/tests/baselines/reference/inheritanceStaticPropertyOverridingProperty.js
index c003eaa60b4..c1bdd9b66a2 100644
--- a/tests/baselines/reference/inheritanceStaticPropertyOverridingProperty.js
+++ b/tests/baselines/reference/inheritanceStaticPropertyOverridingProperty.js
@@ -21,8 +21,7 @@ var a = (function () {
 var b = (function (_super) {
     __extends(b, _super);
     function b() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return b;
 }(a));
diff --git a/tests/baselines/reference/inheritedConstructorWithRestParams.js b/tests/baselines/reference/inheritedConstructorWithRestParams.js
index ca6a379816f..c9db1756676 100644
--- a/tests/baselines/reference/inheritedConstructorWithRestParams.js
+++ b/tests/baselines/reference/inheritedConstructorWithRestParams.js
@@ -32,8 +32,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/inheritedConstructorWithRestParams2.js b/tests/baselines/reference/inheritedConstructorWithRestParams2.js
index b323aefbd48..9a1b13a8434 100644
--- a/tests/baselines/reference/inheritedConstructorWithRestParams2.js
+++ b/tests/baselines/reference/inheritedConstructorWithRestParams2.js
@@ -53,16 +53,14 @@ var BaseBase2 = (function () {
 var Base = (function (_super) {
     __extends(Base, _super);
     function Base() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Base;
 }(BaseBase));
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/inheritedModuleMembersForClodule.js b/tests/baselines/reference/inheritedModuleMembersForClodule.js
index 1de6f5f638a..7ba382e8c47 100644
--- a/tests/baselines/reference/inheritedModuleMembersForClodule.js
+++ b/tests/baselines/reference/inheritedModuleMembersForClodule.js
@@ -38,8 +38,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(C));
@@ -54,8 +53,7 @@ var D;
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     E.bar = function () {
         return this.foo();
diff --git a/tests/baselines/reference/instanceOfAssignability.js b/tests/baselines/reference/instanceOfAssignability.js
index f78378f0885..b8f39c5b0e2 100644
--- a/tests/baselines/reference/instanceOfAssignability.js
+++ b/tests/baselines/reference/instanceOfAssignability.js
@@ -115,16 +115,14 @@ var Animal = (function () {
 var Mammal = (function (_super) {
     __extends(Mammal, _super);
     function Mammal() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Mammal;
 }(Animal));
 var Giraffe = (function (_super) {
     __extends(Giraffe, _super);
     function Giraffe() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Giraffe;
 }(Mammal));
diff --git a/tests/baselines/reference/instancePropertiesInheritedIntoClassType.js b/tests/baselines/reference/instancePropertiesInheritedIntoClassType.js
index cf056e768d8..8dc5227685f 100644
--- a/tests/baselines/reference/instancePropertiesInheritedIntoClassType.js
+++ b/tests/baselines/reference/instancePropertiesInheritedIntoClassType.js
@@ -69,8 +69,7 @@ var NonGeneric;
     var D = (function (_super) {
         __extends(D, _super);
         function D() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D;
     }(C));
@@ -102,8 +101,7 @@ var Generic;
     var D = (function (_super) {
         __extends(D, _super);
         function D() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D;
     }(C));
diff --git a/tests/baselines/reference/instanceSubtypeCheck2.js b/tests/baselines/reference/instanceSubtypeCheck2.js
index e70dc7b6481..914f3796001 100644
--- a/tests/baselines/reference/instanceSubtypeCheck2.js
+++ b/tests/baselines/reference/instanceSubtypeCheck2.js
@@ -21,8 +21,7 @@ var C1 = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }(C1));
diff --git a/tests/baselines/reference/instanceofWithStructurallyIdenticalTypes.js b/tests/baselines/reference/instanceofWithStructurallyIdenticalTypes.js
index de2789caa68..54a574238e5 100644
--- a/tests/baselines/reference/instanceofWithStructurallyIdenticalTypes.js
+++ b/tests/baselines/reference/instanceofWithStructurallyIdenticalTypes.js
@@ -128,8 +128,7 @@ var A = (function () {
 var A1 = (function (_super) {
     __extends(A1, _super);
     function A1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return A1;
 }(A));
@@ -141,8 +140,7 @@ var A2 = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/instantiatedReturnTypeContravariance.js b/tests/baselines/reference/instantiatedReturnTypeContravariance.js
index 83ad38e64f0..bc496a63632 100644
--- a/tests/baselines/reference/instantiatedReturnTypeContravariance.js
+++ b/tests/baselines/reference/instantiatedReturnTypeContravariance.js
@@ -47,8 +47,7 @@ var c = (function () {
 var d = (function (_super) {
     __extends(d, _super);
     function d() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     d.prototype.foo = function () {
         return null;
diff --git a/tests/baselines/reference/interfaceClassMerging.js b/tests/baselines/reference/interfaceClassMerging.js
index 6111e7f8cee..6542376a19b 100644
--- a/tests/baselines/reference/interfaceClassMerging.js
+++ b/tests/baselines/reference/interfaceClassMerging.js
@@ -57,8 +57,7 @@ var Foo = (function () {
 var Bar = (function (_super) {
     __extends(Bar, _super);
     function Bar() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Bar.prototype.method = function (a) {
         return this.optionalProperty;
diff --git a/tests/baselines/reference/interfaceClassMerging2.js b/tests/baselines/reference/interfaceClassMerging2.js
index 499bd219905..70a62da4131 100644
--- a/tests/baselines/reference/interfaceClassMerging2.js
+++ b/tests/baselines/reference/interfaceClassMerging2.js
@@ -53,8 +53,7 @@ var Foo = (function () {
 var Bar = (function (_super) {
     __extends(Bar, _super);
     function Bar() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Bar.prototype.classBarMethod = function () {
         return this;
diff --git a/tests/baselines/reference/interfaceExtendsClass1.js b/tests/baselines/reference/interfaceExtendsClass1.js
index 70ceaa8acd3..8324a001f91 100644
--- a/tests/baselines/reference/interfaceExtendsClass1.js
+++ b/tests/baselines/reference/interfaceExtendsClass1.js
@@ -32,8 +32,7 @@ var Control = (function () {
 var Button = (function (_super) {
     __extends(Button, _super);
     function Button() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Button.prototype.select = function () { };
     return Button;
@@ -41,8 +40,7 @@ var Button = (function (_super) {
 var TextBox = (function (_super) {
     __extends(TextBox, _super);
     function TextBox() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     TextBox.prototype.select = function () { };
     return TextBox;
@@ -50,8 +48,7 @@ var TextBox = (function (_super) {
 var Image = (function (_super) {
     __extends(Image, _super);
     function Image() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Image;
 }(Control));
diff --git a/tests/baselines/reference/interfaceExtendsClassWithPrivate1.js b/tests/baselines/reference/interfaceExtendsClassWithPrivate1.js
index 5e6695dd200..1179ff101df 100644
--- a/tests/baselines/reference/interfaceExtendsClassWithPrivate1.js
+++ b/tests/baselines/reference/interfaceExtendsClassWithPrivate1.js
@@ -43,8 +43,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     D.prototype.foo = function (x) { return x; };
     D.prototype.other = function (x) { return x; };
diff --git a/tests/baselines/reference/interfaceImplementation8.js b/tests/baselines/reference/interfaceImplementation8.js
index f3bfa4db6a5..afb5a795264 100644
--- a/tests/baselines/reference/interfaceImplementation8.js
+++ b/tests/baselines/reference/interfaceImplementation8.js
@@ -64,24 +64,21 @@ var C3 = (function () {
 var C4 = (function (_super) {
     __extends(C4, _super);
     function C4() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C4;
 }(C1));
 var C5 = (function (_super) {
     __extends(C5, _super);
     function C5() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C5;
 }(C2));
 var C6 = (function (_super) {
     __extends(C6, _super);
     function C6() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C6;
 }(C3));
@@ -93,8 +90,7 @@ var C7 = (function () {
 var C8 = (function (_super) {
     __extends(C8, _super);
     function C8() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C8;
 }(C7));
diff --git a/tests/baselines/reference/invalidModuleWithStatementsOfEveryKind.js b/tests/baselines/reference/invalidModuleWithStatementsOfEveryKind.js
index 75bf3f91884..6e9b09c906f 100644
--- a/tests/baselines/reference/invalidModuleWithStatementsOfEveryKind.js
+++ b/tests/baselines/reference/invalidModuleWithStatementsOfEveryKind.js
@@ -95,8 +95,7 @@ var Y;
     var BB = (function (_super) {
         __extends(BB, _super);
         function BB() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return BB;
     }(A));
@@ -111,8 +110,7 @@ var Y2;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(AA));
@@ -146,8 +144,7 @@ var YY;
     var BB = (function (_super) {
         __extends(BB, _super);
         function BB() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return BB;
     }(A));
@@ -162,8 +159,7 @@ var YY2;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(AA));
@@ -197,8 +193,7 @@ var YYY;
     var BB = (function (_super) {
         __extends(BB, _super);
         function BB() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return BB;
     }(A));
@@ -213,8 +208,7 @@ var YYY2;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(AA));
diff --git a/tests/baselines/reference/invalidMultipleVariableDeclarations.js b/tests/baselines/reference/invalidMultipleVariableDeclarations.js
index b4fbd6f3698..340429cc398 100644
--- a/tests/baselines/reference/invalidMultipleVariableDeclarations.js
+++ b/tests/baselines/reference/invalidMultipleVariableDeclarations.js
@@ -67,8 +67,7 @@ var C = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }(C));
diff --git a/tests/baselines/reference/invalidReturnStatements.js b/tests/baselines/reference/invalidReturnStatements.js
index 1409b1c59a8..a6b07b7d7bd 100644
--- a/tests/baselines/reference/invalidReturnStatements.js
+++ b/tests/baselines/reference/invalidReturnStatements.js
@@ -41,8 +41,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/isolatedModulesImportExportElision.js b/tests/baselines/reference/isolatedModulesImportExportElision.js
index baf2d1de129..6f1d38dcbb5 100644
--- a/tests/baselines/reference/isolatedModulesImportExportElision.js
+++ b/tests/baselines/reference/isolatedModulesImportExportElision.js
@@ -26,8 +26,7 @@ var ns = require("module");
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(module_2.c2.C));
diff --git a/tests/baselines/reference/jsxViaImport.js b/tests/baselines/reference/jsxViaImport.js
index c149d4e3c3d..604787af744 100644
--- a/tests/baselines/reference/jsxViaImport.js
+++ b/tests/baselines/reference/jsxViaImport.js
@@ -35,8 +35,7 @@ var BaseComponent = require("BaseComponent");
 var TestComponent = (function (_super) {
     __extends(TestComponent, _super);
     function TestComponent() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     TestComponent.prototype.render = function () {
         return <BaseComponent />;
diff --git a/tests/baselines/reference/lambdaArgCrash.js b/tests/baselines/reference/lambdaArgCrash.js
index 16653cfb4f3..47db7f3ce64 100644
--- a/tests/baselines/reference/lambdaArgCrash.js
+++ b/tests/baselines/reference/lambdaArgCrash.js
@@ -56,8 +56,7 @@ var Event = (function () {
 var ItemSetEvent = (function (_super) {
     __extends(ItemSetEvent, _super);
     function ItemSetEvent() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     ItemSetEvent.prototype.add = function (listener) {
         _super.prototype.add.call(this, listener);
diff --git a/tests/baselines/reference/localTypes1.js b/tests/baselines/reference/localTypes1.js
index 96c9337817d..100452b7a96 100644
--- a/tests/baselines/reference/localTypes1.js
+++ b/tests/baselines/reference/localTypes1.js
@@ -300,8 +300,7 @@ function f6() {
         var B = (function (_super) {
             __extends(B, _super);
             function B() {
-                var _this = _super.apply(this, arguments) || this;
-                return _this;
+                return _super.apply(this, arguments) || this;
             }
             return B;
         }(A));
@@ -309,8 +308,7 @@ function f6() {
             var C = (function (_super) {
                 __extends(C, _super);
                 function C() {
-                    var _this = _super.apply(this, arguments) || this;
-                    return _this;
+                    return _super.apply(this, arguments) || this;
                 }
                 return C;
             }(B));
diff --git a/tests/baselines/reference/m7Bugs.js b/tests/baselines/reference/m7Bugs.js
index 19cd9ee4630..e5a4d11f00c 100644
--- a/tests/baselines/reference/m7Bugs.js
+++ b/tests/baselines/reference/m7Bugs.js
@@ -42,8 +42,7 @@ var C1 = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }(C1));
diff --git a/tests/baselines/reference/mergedDeclarations5.js b/tests/baselines/reference/mergedDeclarations5.js
index 53a8c983399..b24e86eca58 100644
--- a/tests/baselines/reference/mergedDeclarations5.js
+++ b/tests/baselines/reference/mergedDeclarations5.js
@@ -27,8 +27,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     B.prototype.foo = function () { };
     return B;
diff --git a/tests/baselines/reference/mergedDeclarations6.js b/tests/baselines/reference/mergedDeclarations6.js
index 50108773a70..d610e4ab46f 100644
--- a/tests/baselines/reference/mergedDeclarations6.js
+++ b/tests/baselines/reference/mergedDeclarations6.js
@@ -47,8 +47,7 @@ define(["require", "exports", "./a"], function (require, exports, a_1) {
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         B.prototype.setProtected = function () {
         };
diff --git a/tests/baselines/reference/mergedInheritedClassInterface.js b/tests/baselines/reference/mergedInheritedClassInterface.js
index fd0bea5494c..0f598f2cf78 100644
--- a/tests/baselines/reference/mergedInheritedClassInterface.js
+++ b/tests/baselines/reference/mergedInheritedClassInterface.js
@@ -61,8 +61,7 @@ var BaseClass = (function () {
 var Child = (function (_super) {
     __extends(Child, _super);
     function Child() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Child.prototype.method = function () { };
     return Child;
@@ -76,8 +75,7 @@ var ChildNoBaseClass = (function () {
 var Grandchild = (function (_super) {
     __extends(Grandchild, _super);
     function Grandchild() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Grandchild;
 }(ChildNoBaseClass));
diff --git a/tests/baselines/reference/mergedInterfacesWithInheritedPrivates2.js b/tests/baselines/reference/mergedInterfacesWithInheritedPrivates2.js
index a3baa1920e3..6dccf1dfdd9 100644
--- a/tests/baselines/reference/mergedInterfacesWithInheritedPrivates2.js
+++ b/tests/baselines/reference/mergedInterfacesWithInheritedPrivates2.js
@@ -50,16 +50,14 @@ var C2 = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(C));
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return E;
 }(C2));
diff --git a/tests/baselines/reference/mergedInterfacesWithInheritedPrivates3.js b/tests/baselines/reference/mergedInterfacesWithInheritedPrivates3.js
index e21ca151c87..a3ca796575c 100644
--- a/tests/baselines/reference/mergedInterfacesWithInheritedPrivates3.js
+++ b/tests/baselines/reference/mergedInterfacesWithInheritedPrivates3.js
@@ -57,8 +57,7 @@ var C2 = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/moduleAsBaseType.js b/tests/baselines/reference/moduleAsBaseType.js
index 598ddaef2de..fc0533a2470 100644
--- a/tests/baselines/reference/moduleAsBaseType.js
+++ b/tests/baselines/reference/moduleAsBaseType.js
@@ -13,8 +13,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(M));
diff --git a/tests/baselines/reference/moduleImportedForTypeArgumentPosition.js b/tests/baselines/reference/moduleImportedForTypeArgumentPosition.js
index 2f4ac430cc1..51d9eb89b1d 100644
--- a/tests/baselines/reference/moduleImportedForTypeArgumentPosition.js
+++ b/tests/baselines/reference/moduleImportedForTypeArgumentPosition.js
@@ -31,8 +31,7 @@ define(["require", "exports"], function (require, exports) {
     var Test1 = (function (_super) {
         __extends(Test1, _super);
         function Test1() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Test1;
     }(C1));
diff --git a/tests/baselines/reference/moduleWithStatementsOfEveryKind.js b/tests/baselines/reference/moduleWithStatementsOfEveryKind.js
index 11053d76d2d..1558ef742ab 100644
--- a/tests/baselines/reference/moduleWithStatementsOfEveryKind.js
+++ b/tests/baselines/reference/moduleWithStatementsOfEveryKind.js
@@ -79,16 +79,14 @@ var A;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(AA));
     var BB = (function (_super) {
         __extends(BB, _super);
         function BB() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return BB;
     }(A));
@@ -132,8 +130,7 @@ var Y;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(AA));
@@ -141,8 +138,7 @@ var Y;
     var BB = (function (_super) {
         __extends(BB, _super);
         function BB() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return BB;
     }(A));
diff --git a/tests/baselines/reference/multipleInheritance.js b/tests/baselines/reference/multipleInheritance.js
index 80e9a469398..9c0e865cdb7 100644
--- a/tests/baselines/reference/multipleInheritance.js
+++ b/tests/baselines/reference/multipleInheritance.js
@@ -57,32 +57,28 @@ var B2 = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(B1));
 var D1 = (function (_super) {
     __extends(D1, _super);
     function D1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D1;
 }(B1));
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D2;
 }(B2));
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return E;
 }(D1));
@@ -94,8 +90,7 @@ var N = (function () {
 var ND = (function (_super) {
     __extends(ND, _super);
     function ND() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return ND;
 }(N));
@@ -109,8 +104,7 @@ var Good = (function () {
 var Baad = (function (_super) {
     __extends(Baad, _super);
     function Baad() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Baad.prototype.f = function () { return 0; };
     Baad.prototype.g = function (n) { return 0; };
diff --git a/tests/baselines/reference/mutuallyRecursiveGenericBaseTypes2.js b/tests/baselines/reference/mutuallyRecursiveGenericBaseTypes2.js
index 7c5ec66c6be..8b59564d465 100644
--- a/tests/baselines/reference/mutuallyRecursiveGenericBaseTypes2.js
+++ b/tests/baselines/reference/mutuallyRecursiveGenericBaseTypes2.js
@@ -25,8 +25,7 @@ var foo = (function () {
 var foo2 = (function (_super) {
     __extends(foo2, _super);
     function foo2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return foo2;
 }(foo));
diff --git a/tests/baselines/reference/noEmitHelpers.js b/tests/baselines/reference/noEmitHelpers.js
index c3d27cac8a9..fdb7cbab7d4 100644
--- a/tests/baselines/reference/noEmitHelpers.js
+++ b/tests/baselines/reference/noEmitHelpers.js
@@ -13,8 +13,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/noImplicitAnyMissingGetAccessor.js b/tests/baselines/reference/noImplicitAnyMissingGetAccessor.js
index d0e87aba25b..cc4c9422373 100644
--- a/tests/baselines/reference/noImplicitAnyMissingGetAccessor.js
+++ b/tests/baselines/reference/noImplicitAnyMissingGetAccessor.js
@@ -26,8 +26,7 @@ var Parent = (function () {
 var Child = (function (_super) {
     __extends(Child, _super);
     function Child() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Object.defineProperty(Child.prototype, "message", {
         set: function (str) {
diff --git a/tests/baselines/reference/noImplicitAnyMissingSetAccessor.js b/tests/baselines/reference/noImplicitAnyMissingSetAccessor.js
index 1b4119227bc..1323955c05e 100644
--- a/tests/baselines/reference/noImplicitAnyMissingSetAccessor.js
+++ b/tests/baselines/reference/noImplicitAnyMissingSetAccessor.js
@@ -25,8 +25,7 @@ var Parent = (function () {
 var Child = (function (_super) {
     __extends(Child, _super);
     function Child() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Object.defineProperty(Child.prototype, "message", {
         get: function () {
diff --git a/tests/baselines/reference/nonGenericClassExtendingGenericClassWithAny.js b/tests/baselines/reference/nonGenericClassExtendingGenericClassWithAny.js
index bbab8e9ccdd..b0a3365193d 100644
--- a/tests/baselines/reference/nonGenericClassExtendingGenericClassWithAny.js
+++ b/tests/baselines/reference/nonGenericClassExtendingGenericClassWithAny.js
@@ -19,8 +19,7 @@ var Foo = (function () {
 var Bar = (function (_super) {
     __extends(Bar, _super);
     function Bar() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Bar;
 }(Foo)); // Valid
diff --git a/tests/baselines/reference/numericIndexerConstrainsPropertyDeclarations2.js b/tests/baselines/reference/numericIndexerConstrainsPropertyDeclarations2.js
index 1901e169447..92c8b380e00 100644
--- a/tests/baselines/reference/numericIndexerConstrainsPropertyDeclarations2.js
+++ b/tests/baselines/reference/numericIndexerConstrainsPropertyDeclarations2.js
@@ -61,8 +61,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     B.prototype.bar = function () { return ''; };
     return B;
diff --git a/tests/baselines/reference/numericIndexerConstraint3.js b/tests/baselines/reference/numericIndexerConstraint3.js
index 97c3e56d423..29cb75b4234 100644
--- a/tests/baselines/reference/numericIndexerConstraint3.js
+++ b/tests/baselines/reference/numericIndexerConstraint3.js
@@ -26,8 +26,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/numericIndexerConstraint4.js b/tests/baselines/reference/numericIndexerConstraint4.js
index 732f7e2672c..135e169c4a9 100644
--- a/tests/baselines/reference/numericIndexerConstraint4.js
+++ b/tests/baselines/reference/numericIndexerConstraint4.js
@@ -26,8 +26,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/numericIndexerTyping2.js b/tests/baselines/reference/numericIndexerTyping2.js
index 1d38f844384..5b9e797bdec 100644
--- a/tests/baselines/reference/numericIndexerTyping2.js
+++ b/tests/baselines/reference/numericIndexerTyping2.js
@@ -26,8 +26,7 @@ var I = (function () {
 var I2 = (function (_super) {
     __extends(I2, _super);
     function I2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return I2;
 }(I));
diff --git a/tests/baselines/reference/objectTypeHidingMembersOfExtendedObject.js b/tests/baselines/reference/objectTypeHidingMembersOfExtendedObject.js
index 76c18900945..17045d65af0 100644
--- a/tests/baselines/reference/objectTypeHidingMembersOfExtendedObject.js
+++ b/tests/baselines/reference/objectTypeHidingMembersOfExtendedObject.js
@@ -68,8 +68,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/objectTypesIdentityWithNumericIndexers1.js b/tests/baselines/reference/objectTypesIdentityWithNumericIndexers1.js
index 3df18cb27cb..e82cef9bdd6 100644
--- a/tests/baselines/reference/objectTypesIdentityWithNumericIndexers1.js
+++ b/tests/baselines/reference/objectTypesIdentityWithNumericIndexers1.js
@@ -147,16 +147,14 @@ var C = (function () {
 var PA = (function (_super) {
     __extends(PA, _super);
     function PA() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return PA;
 }(A));
 var PB = (function (_super) {
     __extends(PB, _super);
     function PB() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return PB;
 }(B));
diff --git a/tests/baselines/reference/objectTypesIdentityWithNumericIndexers2.js b/tests/baselines/reference/objectTypesIdentityWithNumericIndexers2.js
index e7d2f603d5c..abcea113670 100644
--- a/tests/baselines/reference/objectTypesIdentityWithNumericIndexers2.js
+++ b/tests/baselines/reference/objectTypesIdentityWithNumericIndexers2.js
@@ -140,8 +140,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
@@ -163,16 +162,14 @@ var C = (function () {
 var PA = (function (_super) {
     __extends(PA, _super);
     function PA() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return PA;
 }(A));
 var PB = (function (_super) {
     __extends(PB, _super);
     function PB() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return PB;
 }(B));
diff --git a/tests/baselines/reference/objectTypesIdentityWithNumericIndexers3.js b/tests/baselines/reference/objectTypesIdentityWithNumericIndexers3.js
index e0b75f54208..f5aeb177472 100644
--- a/tests/baselines/reference/objectTypesIdentityWithNumericIndexers3.js
+++ b/tests/baselines/reference/objectTypesIdentityWithNumericIndexers3.js
@@ -147,16 +147,14 @@ var C = (function () {
 var PA = (function (_super) {
     __extends(PA, _super);
     function PA() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return PA;
 }(A));
 var PB = (function (_super) {
     __extends(PB, _super);
     function PB() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return PB;
 }(B));
diff --git a/tests/baselines/reference/objectTypesIdentityWithPrivates.js b/tests/baselines/reference/objectTypesIdentityWithPrivates.js
index 681af407bd4..3946027063f 100644
--- a/tests/baselines/reference/objectTypesIdentityWithPrivates.js
+++ b/tests/baselines/reference/objectTypesIdentityWithPrivates.js
@@ -145,16 +145,14 @@ var C = (function () {
 var PA = (function (_super) {
     __extends(PA, _super);
     function PA() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return PA;
 }(A));
 var PB = (function (_super) {
     __extends(PB, _super);
     function PB() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return PB;
 }(B));
diff --git a/tests/baselines/reference/objectTypesIdentityWithPrivates2.js b/tests/baselines/reference/objectTypesIdentityWithPrivates2.js
index 2011b741df2..9cae6960a2e 100644
--- a/tests/baselines/reference/objectTypesIdentityWithPrivates2.js
+++ b/tests/baselines/reference/objectTypesIdentityWithPrivates2.js
@@ -53,8 +53,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/objectTypesIdentityWithPrivates3.js b/tests/baselines/reference/objectTypesIdentityWithPrivates3.js
index 80bdd4c87e1..68754a583aa 100644
--- a/tests/baselines/reference/objectTypesIdentityWithPrivates3.js
+++ b/tests/baselines/reference/objectTypesIdentityWithPrivates3.js
@@ -39,8 +39,7 @@ var C1 = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }(C1));
@@ -54,8 +53,7 @@ var C3 = (function () {
 var C4 = (function (_super) {
     __extends(C4, _super);
     function C4() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C4;
 }(C3));
diff --git a/tests/baselines/reference/objectTypesIdentityWithStringIndexers.js b/tests/baselines/reference/objectTypesIdentityWithStringIndexers.js
index 3eac80c60fc..b0211bbbba7 100644
--- a/tests/baselines/reference/objectTypesIdentityWithStringIndexers.js
+++ b/tests/baselines/reference/objectTypesIdentityWithStringIndexers.js
@@ -147,16 +147,14 @@ var C = (function () {
 var PA = (function (_super) {
     __extends(PA, _super);
     function PA() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return PA;
 }(A));
 var PB = (function (_super) {
     __extends(PB, _super);
     function PB() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return PB;
 }(B));
diff --git a/tests/baselines/reference/objectTypesIdentityWithStringIndexers2.js b/tests/baselines/reference/objectTypesIdentityWithStringIndexers2.js
index d55ef5eb28c..00d7d1e81d8 100644
--- a/tests/baselines/reference/objectTypesIdentityWithStringIndexers2.js
+++ b/tests/baselines/reference/objectTypesIdentityWithStringIndexers2.js
@@ -140,8 +140,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
@@ -163,16 +162,14 @@ var C = (function () {
 var PA = (function (_super) {
     __extends(PA, _super);
     function PA() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return PA;
 }(A));
 var PB = (function (_super) {
     __extends(PB, _super);
     function PB() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return PB;
 }(B));
diff --git a/tests/baselines/reference/optionalConstructorArgInSuper.js b/tests/baselines/reference/optionalConstructorArgInSuper.js
index 04056fa9c14..e460ab3fb15 100644
--- a/tests/baselines/reference/optionalConstructorArgInSuper.js
+++ b/tests/baselines/reference/optionalConstructorArgInSuper.js
@@ -25,8 +25,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
diff --git a/tests/baselines/reference/optionalParamInOverride.js b/tests/baselines/reference/optionalParamInOverride.js
index a8bd88ed3a8..1312a89502a 100644
--- a/tests/baselines/reference/optionalParamInOverride.js
+++ b/tests/baselines/reference/optionalParamInOverride.js
@@ -22,8 +22,7 @@ var Z = (function () {
 var Y = (function (_super) {
     __extends(Y, _super);
     function Y() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Y.prototype.func = function (value) { };
     return Y;
diff --git a/tests/baselines/reference/outModuleConcatAmd.js b/tests/baselines/reference/outModuleConcatAmd.js
index 5643875efd3..5054c2a3c33 100644
--- a/tests/baselines/reference/outModuleConcatAmd.js
+++ b/tests/baselines/reference/outModuleConcatAmd.js
@@ -28,8 +28,7 @@ define("b", ["require", "exports", "ref/a"], function (require, exports, a_1) {
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(a_1.A));
diff --git a/tests/baselines/reference/outModuleConcatAmd.js.map b/tests/baselines/reference/outModuleConcatAmd.js.map
index 25873d9cd07..e987d5deb8a 100644
--- a/tests/baselines/reference/outModuleConcatAmd.js.map
+++ b/tests/baselines/reference/outModuleConcatAmd.js.map
@@ -1,2 +1,2 @@
 //// [all.js.map]
-{"version":3,"file":"all.js","sourceRoot":"","sources":["tests/cases/compiler/ref/a.ts","tests/cases/compiler/b.ts"],"names":[],"mappings":";;;;;;;IACA;QAAA;QAAiB,CAAC;QAAD,QAAC;IAAD,CAAC,AAAlB,IAAkB;IAAlB,cAAkB;;;;ICAlB;QAAuB,qBAAC;QAAxB;YAAuB,kDAAC;;QAAG,CAAC;QAAD,QAAC;IAAD,CAAC,AAA5B,CAAuB,KAAC,GAAI;IAA5B,cAA4B"}
\ No newline at end of file
+{"version":3,"file":"all.js","sourceRoot":"","sources":["tests/cases/compiler/ref/a.ts","tests/cases/compiler/b.ts"],"names":[],"mappings":";;;;;;;IACA;QAAA;QAAiB,CAAC;QAAD,QAAC;IAAD,CAAC,AAAlB,IAAkB;IAAlB,cAAkB;;;;ICAlB;QAAuB,qBAAC;QAAxB;;QAA2B,CAAC;QAAD,QAAC;IAAD,CAAC,AAA5B,CAAuB,KAAC,GAAI;IAA5B,cAA4B"}
\ No newline at end of file
diff --git a/tests/baselines/reference/outModuleConcatAmd.sourcemap.txt b/tests/baselines/reference/outModuleConcatAmd.sourcemap.txt
index 2fa35a323a0..1bfda049776 100644
--- a/tests/baselines/reference/outModuleConcatAmd.sourcemap.txt
+++ b/tests/baselines/reference/outModuleConcatAmd.sourcemap.txt
@@ -92,35 +92,27 @@ sourceFile:tests/cases/compiler/b.ts
 ---
 >>>        function B() {
 1 >^^^^^^^^
-2 >        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
+2 >        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
 1 >
 1 >Emitted(19, 9) Source(2, 1) + SourceIndex(1)
 ---
->>>            var _this = _super.apply(this, arguments) || this;
-1->^^^^^^^^^^^^
-2 >            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-1->export class B extends 
-2 >            A
-1->Emitted(20, 13) Source(2, 24) + SourceIndex(1)
-2 >Emitted(20, 63) Source(2, 25) + SourceIndex(1)
----
->>>            return _this;
+>>>            return _super.apply(this, arguments) || this;
 >>>        }
-1 >^^^^^^^^
+1->^^^^^^^^
 2 >        ^
 3 >         ^^^^^^^^^->
-1 > { 
+1->export class B extends A { 
 2 >        }
-1 >Emitted(22, 9) Source(2, 28) + SourceIndex(1)
-2 >Emitted(22, 10) Source(2, 29) + SourceIndex(1)
+1->Emitted(21, 9) Source(2, 28) + SourceIndex(1)
+2 >Emitted(21, 10) Source(2, 29) + SourceIndex(1)
 ---
 >>>        return B;
 1->^^^^^^^^
 2 >        ^^^^^^^^
 1->
 2 >        }
-1->Emitted(23, 9) Source(2, 28) + SourceIndex(1)
-2 >Emitted(23, 17) Source(2, 29) + SourceIndex(1)
+1->Emitted(22, 9) Source(2, 28) + SourceIndex(1)
+2 >Emitted(22, 17) Source(2, 29) + SourceIndex(1)
 ---
 >>>    }(a_1.A));
 1 >^^^^
@@ -136,20 +128,20 @@ sourceFile:tests/cases/compiler/b.ts
 4 >     export class B extends 
 5 >      A
 6 >            { }
-1 >Emitted(24, 5) Source(2, 28) + SourceIndex(1)
-2 >Emitted(24, 6) Source(2, 29) + SourceIndex(1)
-3 >Emitted(24, 6) Source(2, 1) + SourceIndex(1)
-4 >Emitted(24, 7) Source(2, 24) + SourceIndex(1)
-5 >Emitted(24, 12) Source(2, 25) + SourceIndex(1)
-6 >Emitted(24, 15) Source(2, 29) + SourceIndex(1)
+1 >Emitted(23, 5) Source(2, 28) + SourceIndex(1)
+2 >Emitted(23, 6) Source(2, 29) + SourceIndex(1)
+3 >Emitted(23, 6) Source(2, 1) + SourceIndex(1)
+4 >Emitted(23, 7) Source(2, 24) + SourceIndex(1)
+5 >Emitted(23, 12) Source(2, 25) + SourceIndex(1)
+6 >Emitted(23, 15) Source(2, 29) + SourceIndex(1)
 ---
 >>>    exports.B = B;
 1->^^^^
 2 >    ^^^^^^^^^^^^^^
 1->
 2 >    export class B extends A { }
-1->Emitted(25, 5) Source(2, 1) + SourceIndex(1)
-2 >Emitted(25, 19) Source(2, 29) + SourceIndex(1)
+1->Emitted(24, 5) Source(2, 1) + SourceIndex(1)
+2 >Emitted(24, 19) Source(2, 29) + SourceIndex(1)
 ---
 >>>});
 >>>//# sourceMappingURL=all.js.map
\ No newline at end of file
diff --git a/tests/baselines/reference/outModuleConcatSystem.js b/tests/baselines/reference/outModuleConcatSystem.js
index eecb4101958..a615090f33a 100644
--- a/tests/baselines/reference/outModuleConcatSystem.js
+++ b/tests/baselines/reference/outModuleConcatSystem.js
@@ -44,8 +44,7 @@ System.register("b", ["ref/a"], function (exports_2, context_2) {
             B = (function (_super) {
                 __extends(B, _super);
                 function B() {
-                    var _this = _super.apply(this, arguments) || this;
-                    return _this;
+                    return _super.apply(this, arguments) || this;
                 }
                 return B;
             }(a_1.A));
diff --git a/tests/baselines/reference/outModuleConcatSystem.js.map b/tests/baselines/reference/outModuleConcatSystem.js.map
index f77bed44ffc..ac8fb23d87c 100644
--- a/tests/baselines/reference/outModuleConcatSystem.js.map
+++ b/tests/baselines/reference/outModuleConcatSystem.js.map
@@ -1,2 +1,2 @@
 //// [all.js.map]
-{"version":3,"file":"all.js","sourceRoot":"","sources":["tests/cases/compiler/ref/a.ts","tests/cases/compiler/b.ts"],"names":[],"mappings":";;;;;;;;;;;;YACA;gBAAA;gBAAiB,CAAC;gBAAD,QAAC;YAAD,CAAC,AAAlB,IAAkB;;QAClB,CAAC;;;;;;;;;;;;;;YCDD;gBAAuB,qBAAC;gBAAxB;oBAAuB,kDAAC;;gBAAG,CAAC;gBAAD,QAAC;YAAD,CAAC,AAA5B,CAAuB,KAAC,GAAI;;QAAA,CAAC"}
\ No newline at end of file
+{"version":3,"file":"all.js","sourceRoot":"","sources":["tests/cases/compiler/ref/a.ts","tests/cases/compiler/b.ts"],"names":[],"mappings":";;;;;;;;;;;;YACA;gBAAA;gBAAiB,CAAC;gBAAD,QAAC;YAAD,CAAC,AAAlB,IAAkB;;QAClB,CAAC;;;;;;;;;;;;;;YCDD;gBAAuB,qBAAC;gBAAxB;;gBAA2B,CAAC;gBAAD,QAAC;YAAD,CAAC,AAA5B,CAAuB,KAAC,GAAI;;QAAA,CAAC"}
\ No newline at end of file
diff --git a/tests/baselines/reference/outModuleConcatSystem.sourcemap.txt b/tests/baselines/reference/outModuleConcatSystem.sourcemap.txt
index 5287a760ac8..732214237fa 100644
--- a/tests/baselines/reference/outModuleConcatSystem.sourcemap.txt
+++ b/tests/baselines/reference/outModuleConcatSystem.sourcemap.txt
@@ -109,35 +109,27 @@ sourceFile:tests/cases/compiler/b.ts
 ---
 >>>                function B() {
 1 >^^^^^^^^^^^^^^^^
-2 >                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
+2 >                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
 1 >
 1 >Emitted(35, 17) Source(2, 1) + SourceIndex(1)
 ---
->>>                    var _this = _super.apply(this, arguments) || this;
-1->^^^^^^^^^^^^^^^^^^^^
-2 >                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-1->export class B extends 
-2 >                    A
-1->Emitted(36, 21) Source(2, 24) + SourceIndex(1)
-2 >Emitted(36, 71) Source(2, 25) + SourceIndex(1)
----
->>>                    return _this;
+>>>                    return _super.apply(this, arguments) || this;
 >>>                }
-1 >^^^^^^^^^^^^^^^^
+1->^^^^^^^^^^^^^^^^
 2 >                ^
 3 >                 ^^^^^^^^^->
-1 > { 
+1->export class B extends A { 
 2 >                }
-1 >Emitted(38, 17) Source(2, 28) + SourceIndex(1)
-2 >Emitted(38, 18) Source(2, 29) + SourceIndex(1)
+1->Emitted(37, 17) Source(2, 28) + SourceIndex(1)
+2 >Emitted(37, 18) Source(2, 29) + SourceIndex(1)
 ---
 >>>                return B;
 1->^^^^^^^^^^^^^^^^
 2 >                ^^^^^^^^
 1->
 2 >                }
-1->Emitted(39, 17) Source(2, 28) + SourceIndex(1)
-2 >Emitted(39, 25) Source(2, 29) + SourceIndex(1)
+1->Emitted(38, 17) Source(2, 28) + SourceIndex(1)
+2 >Emitted(38, 25) Source(2, 29) + SourceIndex(1)
 ---
 >>>            }(a_1.A));
 1 >^^^^^^^^^^^^
@@ -153,12 +145,12 @@ sourceFile:tests/cases/compiler/b.ts
 4 >             export class B extends 
 5 >              A
 6 >                    { }
-1 >Emitted(40, 13) Source(2, 28) + SourceIndex(1)
-2 >Emitted(40, 14) Source(2, 29) + SourceIndex(1)
-3 >Emitted(40, 14) Source(2, 1) + SourceIndex(1)
-4 >Emitted(40, 15) Source(2, 24) + SourceIndex(1)
-5 >Emitted(40, 20) Source(2, 25) + SourceIndex(1)
-6 >Emitted(40, 23) Source(2, 29) + SourceIndex(1)
+1 >Emitted(39, 13) Source(2, 28) + SourceIndex(1)
+2 >Emitted(39, 14) Source(2, 29) + SourceIndex(1)
+3 >Emitted(39, 14) Source(2, 1) + SourceIndex(1)
+4 >Emitted(39, 15) Source(2, 24) + SourceIndex(1)
+5 >Emitted(39, 20) Source(2, 25) + SourceIndex(1)
+6 >Emitted(39, 23) Source(2, 29) + SourceIndex(1)
 ---
 >>>            exports_2("B", B);
 >>>        }
@@ -166,8 +158,8 @@ sourceFile:tests/cases/compiler/b.ts
 2 >        ^
 1->
 2 >        
-1->Emitted(42, 9) Source(2, 29) + SourceIndex(1)
-2 >Emitted(42, 10) Source(2, 30) + SourceIndex(1)
+1->Emitted(41, 9) Source(2, 29) + SourceIndex(1)
+2 >Emitted(41, 10) Source(2, 30) + SourceIndex(1)
 ---
 >>>    };
 >>>});
diff --git a/tests/baselines/reference/outModuleTripleSlashRefs.js b/tests/baselines/reference/outModuleTripleSlashRefs.js
index ac2f2510b64..b9ff7c15b61 100644
--- a/tests/baselines/reference/outModuleTripleSlashRefs.js
+++ b/tests/baselines/reference/outModuleTripleSlashRefs.js
@@ -57,8 +57,7 @@ define("b", ["require", "exports", "ref/a"], function (require, exports, a_1) {
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(a_1.A));
diff --git a/tests/baselines/reference/outModuleTripleSlashRefs.js.map b/tests/baselines/reference/outModuleTripleSlashRefs.js.map
index 1cdbef49afa..45d57990450 100644
--- a/tests/baselines/reference/outModuleTripleSlashRefs.js.map
+++ b/tests/baselines/reference/outModuleTripleSlashRefs.js.map
@@ -1,2 +1,2 @@
 //// [all.js.map]
-{"version":3,"file":"all.js","sourceRoot":"","sources":["tests/cases/compiler/ref/b.ts","tests/cases/compiler/ref/a.ts","tests/cases/compiler/b.ts"],"names":[],"mappings":";;;;;AAAA,iCAAiC;AACjC;IAAA;IAEA,CAAC;IAAD,UAAC;AAAD,CAAC,AAFD,IAEC;;;ICFD,+BAA+B;IAC/B;QAAA;QAEA,CAAC;QAAD,QAAC;IAAD,CAAC,AAFD,IAEC;IAFD,cAEC;;;;ICHD;QAAuB,qBAAC;QAAxB;YAAuB,kDAAC;;QAAG,CAAC;QAAD,QAAC;IAAD,CAAC,AAA5B,CAAuB,KAAC,GAAI;IAA5B,cAA4B"}
\ No newline at end of file
+{"version":3,"file":"all.js","sourceRoot":"","sources":["tests/cases/compiler/ref/b.ts","tests/cases/compiler/ref/a.ts","tests/cases/compiler/b.ts"],"names":[],"mappings":";;;;;AAAA,iCAAiC;AACjC;IAAA;IAEA,CAAC;IAAD,UAAC;AAAD,CAAC,AAFD,IAEC;;;ICFD,+BAA+B;IAC/B;QAAA;QAEA,CAAC;QAAD,QAAC;IAAD,CAAC,AAFD,IAEC;IAFD,cAEC;;;;ICHD;QAAuB,qBAAC;QAAxB;;QAA2B,CAAC;QAAD,QAAC;IAAD,CAAC,AAA5B,CAAuB,KAAC,GAAI;IAA5B,cAA4B"}
\ No newline at end of file
diff --git a/tests/baselines/reference/outModuleTripleSlashRefs.sourcemap.txt b/tests/baselines/reference/outModuleTripleSlashRefs.sourcemap.txt
index e940429a74b..482c898e0cb 100644
--- a/tests/baselines/reference/outModuleTripleSlashRefs.sourcemap.txt
+++ b/tests/baselines/reference/outModuleTripleSlashRefs.sourcemap.txt
@@ -168,35 +168,27 @@ sourceFile:tests/cases/compiler/b.ts
 ---
 >>>        function B() {
 1 >^^^^^^^^
-2 >        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
+2 >        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
 1 >
 1 >Emitted(26, 9) Source(2, 1) + SourceIndex(2)
 ---
->>>            var _this = _super.apply(this, arguments) || this;
-1->^^^^^^^^^^^^
-2 >            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-1->export class B extends 
-2 >            A
-1->Emitted(27, 13) Source(2, 24) + SourceIndex(2)
-2 >Emitted(27, 63) Source(2, 25) + SourceIndex(2)
----
->>>            return _this;
+>>>            return _super.apply(this, arguments) || this;
 >>>        }
-1 >^^^^^^^^
+1->^^^^^^^^
 2 >        ^
 3 >         ^^^^^^^^^->
-1 > { 
+1->export class B extends A { 
 2 >        }
-1 >Emitted(29, 9) Source(2, 28) + SourceIndex(2)
-2 >Emitted(29, 10) Source(2, 29) + SourceIndex(2)
+1->Emitted(28, 9) Source(2, 28) + SourceIndex(2)
+2 >Emitted(28, 10) Source(2, 29) + SourceIndex(2)
 ---
 >>>        return B;
 1->^^^^^^^^
 2 >        ^^^^^^^^
 1->
 2 >        }
-1->Emitted(30, 9) Source(2, 28) + SourceIndex(2)
-2 >Emitted(30, 17) Source(2, 29) + SourceIndex(2)
+1->Emitted(29, 9) Source(2, 28) + SourceIndex(2)
+2 >Emitted(29, 17) Source(2, 29) + SourceIndex(2)
 ---
 >>>    }(a_1.A));
 1 >^^^^
@@ -212,20 +204,20 @@ sourceFile:tests/cases/compiler/b.ts
 4 >     export class B extends 
 5 >      A
 6 >            { }
-1 >Emitted(31, 5) Source(2, 28) + SourceIndex(2)
-2 >Emitted(31, 6) Source(2, 29) + SourceIndex(2)
-3 >Emitted(31, 6) Source(2, 1) + SourceIndex(2)
-4 >Emitted(31, 7) Source(2, 24) + SourceIndex(2)
-5 >Emitted(31, 12) Source(2, 25) + SourceIndex(2)
-6 >Emitted(31, 15) Source(2, 29) + SourceIndex(2)
+1 >Emitted(30, 5) Source(2, 28) + SourceIndex(2)
+2 >Emitted(30, 6) Source(2, 29) + SourceIndex(2)
+3 >Emitted(30, 6) Source(2, 1) + SourceIndex(2)
+4 >Emitted(30, 7) Source(2, 24) + SourceIndex(2)
+5 >Emitted(30, 12) Source(2, 25) + SourceIndex(2)
+6 >Emitted(30, 15) Source(2, 29) + SourceIndex(2)
 ---
 >>>    exports.B = B;
 1->^^^^
 2 >    ^^^^^^^^^^^^^^
 1->
 2 >    export class B extends A { }
-1->Emitted(32, 5) Source(2, 1) + SourceIndex(2)
-2 >Emitted(32, 19) Source(2, 29) + SourceIndex(2)
+1->Emitted(31, 5) Source(2, 1) + SourceIndex(2)
+2 >Emitted(31, 19) Source(2, 29) + SourceIndex(2)
 ---
 >>>});
 >>>//# sourceMappingURL=all.js.map
\ No newline at end of file
diff --git a/tests/baselines/reference/overload1.js b/tests/baselines/reference/overload1.js
index d83c8aea7ad..41aafdfb29c 100644
--- a/tests/baselines/reference/overload1.js
+++ b/tests/baselines/reference/overload1.js
@@ -56,8 +56,7 @@ var O;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(A));
@@ -65,8 +64,7 @@ var O;
     var C = (function (_super) {
         __extends(C, _super);
         function C() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return C;
     }(B));
diff --git a/tests/baselines/reference/overloadOnConstConstraintChecks1.js b/tests/baselines/reference/overloadOnConstConstraintChecks1.js
index ad49f8e9d7a..f9d1c81b06b 100644
--- a/tests/baselines/reference/overloadOnConstConstraintChecks1.js
+++ b/tests/baselines/reference/overloadOnConstConstraintChecks1.js
@@ -37,8 +37,7 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived1.prototype.bar = function () { };
     return Derived1;
@@ -46,8 +45,7 @@ var Derived1 = (function (_super) {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived2.prototype.baz = function () { };
     return Derived2;
@@ -55,8 +53,7 @@ var Derived2 = (function (_super) {
 var Derived3 = (function (_super) {
     __extends(Derived3, _super);
     function Derived3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived3.prototype.biz = function () { };
     return Derived3;
diff --git a/tests/baselines/reference/overloadOnConstConstraintChecks2.js b/tests/baselines/reference/overloadOnConstConstraintChecks2.js
index 2b521b4baf5..a680a62ddfe 100644
--- a/tests/baselines/reference/overloadOnConstConstraintChecks2.js
+++ b/tests/baselines/reference/overloadOnConstConstraintChecks2.js
@@ -25,16 +25,14 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     C.prototype.foo = function () { };
     return C;
diff --git a/tests/baselines/reference/overloadOnConstConstraintChecks3.js b/tests/baselines/reference/overloadOnConstConstraintChecks3.js
index df5e0065adb..025e449fd6f 100644
--- a/tests/baselines/reference/overloadOnConstConstraintChecks3.js
+++ b/tests/baselines/reference/overloadOnConstConstraintChecks3.js
@@ -27,16 +27,14 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     C.prototype.foo = function () { };
     return C;
diff --git a/tests/baselines/reference/overloadOnConstConstraintChecks4.js b/tests/baselines/reference/overloadOnConstConstraintChecks4.js
index 49d96b97b74..0f436a5f0b2 100644
--- a/tests/baselines/reference/overloadOnConstConstraintChecks4.js
+++ b/tests/baselines/reference/overloadOnConstConstraintChecks4.js
@@ -36,16 +36,14 @@ var A = (function (_super) {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     C.prototype.foo = function () { };
     return C;
diff --git a/tests/baselines/reference/overloadOnConstantsInvalidOverload1.js b/tests/baselines/reference/overloadOnConstantsInvalidOverload1.js
index 5d0546d0edc..e3f58c0f7d0 100644
--- a/tests/baselines/reference/overloadOnConstantsInvalidOverload1.js
+++ b/tests/baselines/reference/overloadOnConstantsInvalidOverload1.js
@@ -26,8 +26,7 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived1.prototype.bar = function () { };
     return Derived1;
@@ -35,8 +34,7 @@ var Derived1 = (function (_super) {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived2.prototype.baz = function () { };
     return Derived2;
@@ -44,8 +42,7 @@ var Derived2 = (function (_super) {
 var Derived3 = (function (_super) {
     __extends(Derived3, _super);
     function Derived3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived3.prototype.biz = function () { };
     return Derived3;
diff --git a/tests/baselines/reference/overloadResolution.js b/tests/baselines/reference/overloadResolution.js
index c34d037b350..e5cc35c39c4 100644
--- a/tests/baselines/reference/overloadResolution.js
+++ b/tests/baselines/reference/overloadResolution.js
@@ -108,24 +108,21 @@ var SomeBase = (function () {
 var SomeDerived1 = (function (_super) {
     __extends(SomeDerived1, _super);
     function SomeDerived1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return SomeDerived1;
 }(SomeBase));
 var SomeDerived2 = (function (_super) {
     __extends(SomeDerived2, _super);
     function SomeDerived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return SomeDerived2;
 }(SomeBase));
 var SomeDerived3 = (function (_super) {
     __extends(SomeDerived3, _super);
     function SomeDerived3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return SomeDerived3;
 }(SomeBase));
diff --git a/tests/baselines/reference/overloadResolutionClassConstructors.js b/tests/baselines/reference/overloadResolutionClassConstructors.js
index 0a899584c18..7c8b2e2ccb6 100644
--- a/tests/baselines/reference/overloadResolutionClassConstructors.js
+++ b/tests/baselines/reference/overloadResolutionClassConstructors.js
@@ -115,24 +115,21 @@ var SomeBase = (function () {
 var SomeDerived1 = (function (_super) {
     __extends(SomeDerived1, _super);
     function SomeDerived1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return SomeDerived1;
 }(SomeBase));
 var SomeDerived2 = (function (_super) {
     __extends(SomeDerived2, _super);
     function SomeDerived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return SomeDerived2;
 }(SomeBase));
 var SomeDerived3 = (function (_super) {
     __extends(SomeDerived3, _super);
     function SomeDerived3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return SomeDerived3;
 }(SomeBase));
diff --git a/tests/baselines/reference/overloadResolutionConstructors.js b/tests/baselines/reference/overloadResolutionConstructors.js
index 42dceff061e..44bbfbcec2b 100644
--- a/tests/baselines/reference/overloadResolutionConstructors.js
+++ b/tests/baselines/reference/overloadResolutionConstructors.js
@@ -116,24 +116,21 @@ var SomeBase = (function () {
 var SomeDerived1 = (function (_super) {
     __extends(SomeDerived1, _super);
     function SomeDerived1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return SomeDerived1;
 }(SomeBase));
 var SomeDerived2 = (function (_super) {
     __extends(SomeDerived2, _super);
     function SomeDerived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return SomeDerived2;
 }(SomeBase));
 var SomeDerived3 = (function (_super) {
     __extends(SomeDerived3, _super);
     function SomeDerived3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return SomeDerived3;
 }(SomeBase));
diff --git a/tests/baselines/reference/overloadingOnConstants1.js b/tests/baselines/reference/overloadingOnConstants1.js
index 52d8a1b7abe..96f4f7baf24 100644
--- a/tests/baselines/reference/overloadingOnConstants1.js
+++ b/tests/baselines/reference/overloadingOnConstants1.js
@@ -40,8 +40,7 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived1.prototype.bar = function () { };
     return Derived1;
@@ -49,8 +48,7 @@ var Derived1 = (function (_super) {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived2.prototype.baz = function () { };
     return Derived2;
@@ -58,8 +56,7 @@ var Derived2 = (function (_super) {
 var Derived3 = (function (_super) {
     __extends(Derived3, _super);
     function Derived3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived3.prototype.biz = function () { };
     return Derived3;
diff --git a/tests/baselines/reference/overloadingOnConstants2.js b/tests/baselines/reference/overloadingOnConstants2.js
index 85976ae7fcd..0c34d0f4b76 100644
--- a/tests/baselines/reference/overloadingOnConstants2.js
+++ b/tests/baselines/reference/overloadingOnConstants2.js
@@ -42,8 +42,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/overridingPrivateStaticMembers.js b/tests/baselines/reference/overridingPrivateStaticMembers.js
index b7ad5b66554..ca5616450ba 100644
--- a/tests/baselines/reference/overridingPrivateStaticMembers.js
+++ b/tests/baselines/reference/overridingPrivateStaticMembers.js
@@ -21,8 +21,7 @@ var Base2 = (function () {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Base2));
diff --git a/tests/baselines/reference/parseErrorInHeritageClause1.js b/tests/baselines/reference/parseErrorInHeritageClause1.js
index 0a29bdf2da0..a9ca0a6db73 100644
--- a/tests/baselines/reference/parseErrorInHeritageClause1.js
+++ b/tests/baselines/reference/parseErrorInHeritageClause1.js
@@ -11,8 +11,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/parser509630.js b/tests/baselines/reference/parser509630.js
index cdef63aa80f..d3648dc5b64 100644
--- a/tests/baselines/reference/parser509630.js
+++ b/tests/baselines/reference/parser509630.js
@@ -21,8 +21,7 @@ var Type = (function () {
 var Any = (function (_super) {
     __extends(Any, _super);
     function Any() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Any;
 }(Type));
diff --git a/tests/baselines/reference/parserAstSpans1.js b/tests/baselines/reference/parserAstSpans1.js
index c7bdb90775e..6b86353b959 100644
--- a/tests/baselines/reference/parserAstSpans1.js
+++ b/tests/baselines/reference/parserAstSpans1.js
@@ -363,8 +363,7 @@ c2_i.nc_f1();
 var c4 = (function (_super) {
     __extends(c4, _super);
     function c4() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return c4;
 }(c2));
diff --git a/tests/baselines/reference/parserClassDeclaration1.js b/tests/baselines/reference/parserClassDeclaration1.js
index f91efad621e..a61b492b7a9 100644
--- a/tests/baselines/reference/parserClassDeclaration1.js
+++ b/tests/baselines/reference/parserClassDeclaration1.js
@@ -11,8 +11,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/parserClassDeclaration3.js b/tests/baselines/reference/parserClassDeclaration3.js
index 9d51b0ed25e..f58f0ab00cb 100644
--- a/tests/baselines/reference/parserClassDeclaration3.js
+++ b/tests/baselines/reference/parserClassDeclaration3.js
@@ -11,8 +11,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(B));
diff --git a/tests/baselines/reference/parserClassDeclaration4.js b/tests/baselines/reference/parserClassDeclaration4.js
index 7c91281d05c..912aa8c6581 100644
--- a/tests/baselines/reference/parserClassDeclaration4.js
+++ b/tests/baselines/reference/parserClassDeclaration4.js
@@ -11,8 +11,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/parserClassDeclaration5.js b/tests/baselines/reference/parserClassDeclaration5.js
index aeb7ce09190..054aaf0eb7a 100644
--- a/tests/baselines/reference/parserClassDeclaration5.js
+++ b/tests/baselines/reference/parserClassDeclaration5.js
@@ -11,8 +11,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/parserClassDeclaration6.js b/tests/baselines/reference/parserClassDeclaration6.js
index b14257310c4..1423edfe037 100644
--- a/tests/baselines/reference/parserClassDeclaration6.js
+++ b/tests/baselines/reference/parserClassDeclaration6.js
@@ -11,8 +11,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/parserErrorRecovery_ExtendsOrImplementsClause2.js b/tests/baselines/reference/parserErrorRecovery_ExtendsOrImplementsClause2.js
index c4a2fd29711..aa0679bb8f5 100644
--- a/tests/baselines/reference/parserErrorRecovery_ExtendsOrImplementsClause2.js
+++ b/tests/baselines/reference/parserErrorRecovery_ExtendsOrImplementsClause2.js
@@ -11,8 +11,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/parserErrorRecovery_ExtendsOrImplementsClause4.js b/tests/baselines/reference/parserErrorRecovery_ExtendsOrImplementsClause4.js
index ae9d5068e29..1308c7c194b 100644
--- a/tests/baselines/reference/parserErrorRecovery_ExtendsOrImplementsClause4.js
+++ b/tests/baselines/reference/parserErrorRecovery_ExtendsOrImplementsClause4.js
@@ -11,8 +11,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/parserErrorRecovery_ExtendsOrImplementsClause5.js b/tests/baselines/reference/parserErrorRecovery_ExtendsOrImplementsClause5.js
index 8992706cd16..b1471628fbd 100644
--- a/tests/baselines/reference/parserErrorRecovery_ExtendsOrImplementsClause5.js
+++ b/tests/baselines/reference/parserErrorRecovery_ExtendsOrImplementsClause5.js
@@ -11,8 +11,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/parserGenericsInTypeContexts1.js b/tests/baselines/reference/parserGenericsInTypeContexts1.js
index 0ec560c1306..641d296dc43 100644
--- a/tests/baselines/reference/parserGenericsInTypeContexts1.js
+++ b/tests/baselines/reference/parserGenericsInTypeContexts1.js
@@ -26,8 +26,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/parserGenericsInTypeContexts2.js b/tests/baselines/reference/parserGenericsInTypeContexts2.js
index d4c754fb0b1..b0f14a090ae 100644
--- a/tests/baselines/reference/parserGenericsInTypeContexts2.js
+++ b/tests/baselines/reference/parserGenericsInTypeContexts2.js
@@ -26,8 +26,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/primitiveMembers.js b/tests/baselines/reference/primitiveMembers.js
index 5425696b133..7b94b555eb1 100644
--- a/tests/baselines/reference/primitiveMembers.js
+++ b/tests/baselines/reference/primitiveMembers.js
@@ -63,8 +63,7 @@ var baz = (function () {
 var foo = (function (_super) {
     __extends(foo, _super);
     function foo() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     foo.prototype.bar = function () { return undefined; };
     ;
diff --git a/tests/baselines/reference/privacyClass.js b/tests/baselines/reference/privacyClass.js
index 8181d0612a8..7e56edf2cf1 100644
--- a/tests/baselines/reference/privacyClass.js
+++ b/tests/baselines/reference/privacyClass.js
@@ -152,24 +152,21 @@ var m1;
     var m1_C1_private = (function (_super) {
         __extends(m1_C1_private, _super);
         function m1_C1_private() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return m1_C1_private;
     }(m1_c_public));
     var m1_C2_private = (function (_super) {
         __extends(m1_C2_private, _super);
         function m1_C2_private() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return m1_C2_private;
     }(m1_c_private));
     var m1_C3_public = (function (_super) {
         __extends(m1_C3_public, _super);
         function m1_C3_public() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return m1_C3_public;
     }(m1_c_public));
@@ -177,8 +174,7 @@ var m1;
     var m1_C4_public = (function (_super) {
         __extends(m1_C4_public, _super);
         function m1_C4_public() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return m1_C4_public;
     }(m1_c_private));
@@ -208,24 +204,21 @@ var m1;
     var m1_C9_private = (function (_super) {
         __extends(m1_C9_private, _super);
         function m1_C9_private() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return m1_C9_private;
     }(m1_c_public));
     var m1_C10_private = (function (_super) {
         __extends(m1_C10_private, _super);
         function m1_C10_private() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return m1_C10_private;
     }(m1_c_private));
     var m1_C11_public = (function (_super) {
         __extends(m1_C11_public, _super);
         function m1_C11_public() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return m1_C11_public;
     }(m1_c_public));
@@ -233,8 +226,7 @@ var m1;
     var m1_C12_public = (function (_super) {
         __extends(m1_C12_public, _super);
         function m1_C12_public() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return m1_C12_public;
     }(m1_c_private));
@@ -258,24 +250,21 @@ var m2;
     var m2_C1_private = (function (_super) {
         __extends(m2_C1_private, _super);
         function m2_C1_private() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return m2_C1_private;
     }(m2_c_public));
     var m2_C2_private = (function (_super) {
         __extends(m2_C2_private, _super);
         function m2_C2_private() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return m2_C2_private;
     }(m2_c_private));
     var m2_C3_public = (function (_super) {
         __extends(m2_C3_public, _super);
         function m2_C3_public() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return m2_C3_public;
     }(m2_c_public));
@@ -283,8 +272,7 @@ var m2;
     var m2_C4_public = (function (_super) {
         __extends(m2_C4_public, _super);
         function m2_C4_public() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return m2_C4_public;
     }(m2_c_private));
@@ -314,24 +302,21 @@ var m2;
     var m2_C9_private = (function (_super) {
         __extends(m2_C9_private, _super);
         function m2_C9_private() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return m2_C9_private;
     }(m2_c_public));
     var m2_C10_private = (function (_super) {
         __extends(m2_C10_private, _super);
         function m2_C10_private() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return m2_C10_private;
     }(m2_c_private));
     var m2_C11_public = (function (_super) {
         __extends(m2_C11_public, _super);
         function m2_C11_public() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return m2_C11_public;
     }(m2_c_public));
@@ -339,8 +324,7 @@ var m2;
     var m2_C12_public = (function (_super) {
         __extends(m2_C12_public, _super);
         function m2_C12_public() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return m2_C12_public;
     }(m2_c_private));
@@ -362,24 +346,21 @@ var glo_c_private = (function () {
 var glo_C1_private = (function (_super) {
     __extends(glo_C1_private, _super);
     function glo_C1_private() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return glo_C1_private;
 }(glo_c_public));
 var glo_C2_private = (function (_super) {
     __extends(glo_C2_private, _super);
     function glo_C2_private() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return glo_C2_private;
 }(glo_c_private));
 var glo_C3_public = (function (_super) {
     __extends(glo_C3_public, _super);
     function glo_C3_public() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return glo_C3_public;
 }(glo_c_public));
@@ -387,8 +368,7 @@ exports.glo_C3_public = glo_C3_public;
 var glo_C4_public = (function (_super) {
     __extends(glo_C4_public, _super);
     function glo_C4_public() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return glo_C4_public;
 }(glo_c_private));
@@ -418,24 +398,21 @@ exports.glo_C8_public = glo_C8_public;
 var glo_C9_private = (function (_super) {
     __extends(glo_C9_private, _super);
     function glo_C9_private() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return glo_C9_private;
 }(glo_c_public));
 var glo_C10_private = (function (_super) {
     __extends(glo_C10_private, _super);
     function glo_C10_private() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return glo_C10_private;
 }(glo_c_private));
 var glo_C11_public = (function (_super) {
     __extends(glo_C11_public, _super);
     function glo_C11_public() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return glo_C11_public;
 }(glo_c_public));
@@ -443,8 +420,7 @@ exports.glo_C11_public = glo_C11_public;
 var glo_C12_public = (function (_super) {
     __extends(glo_C12_public, _super);
     function glo_C12_public() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return glo_C12_public;
 }(glo_c_private));
diff --git a/tests/baselines/reference/privacyClassExtendsClauseDeclFile.js b/tests/baselines/reference/privacyClassExtendsClauseDeclFile.js
index fe3ae6ba6d0..e0828809416 100644
--- a/tests/baselines/reference/privacyClassExtendsClauseDeclFile.js
+++ b/tests/baselines/reference/privacyClassExtendsClauseDeclFile.js
@@ -122,24 +122,21 @@ var publicModule;
     var privateClassExtendingPublicClassInModule = (function (_super) {
         __extends(privateClassExtendingPublicClassInModule, _super);
         function privateClassExtendingPublicClassInModule() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return privateClassExtendingPublicClassInModule;
     }(publicClassInPublicModule));
     var privateClassExtendingPrivateClassInModule = (function (_super) {
         __extends(privateClassExtendingPrivateClassInModule, _super);
         function privateClassExtendingPrivateClassInModule() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return privateClassExtendingPrivateClassInModule;
     }(privateClassInPublicModule));
     var publicClassExtendingPublicClassInModule = (function (_super) {
         __extends(publicClassExtendingPublicClassInModule, _super);
         function publicClassExtendingPublicClassInModule() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return publicClassExtendingPublicClassInModule;
     }(publicClassInPublicModule));
@@ -147,8 +144,7 @@ var publicModule;
     var publicClassExtendingPrivateClassInModule = (function (_super) {
         __extends(publicClassExtendingPrivateClassInModule, _super);
         function publicClassExtendingPrivateClassInModule() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return publicClassExtendingPrivateClassInModule;
     }(privateClassInPublicModule));
@@ -156,16 +152,14 @@ var publicModule;
     var privateClassExtendingFromPrivateModuleClass = (function (_super) {
         __extends(privateClassExtendingFromPrivateModuleClass, _super);
         function privateClassExtendingFromPrivateModuleClass() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return privateClassExtendingFromPrivateModuleClass;
     }(privateModule.publicClassInPrivateModule));
     var publicClassExtendingFromPrivateModuleClass = (function (_super) {
         __extends(publicClassExtendingFromPrivateModuleClass, _super);
         function publicClassExtendingFromPrivateModuleClass() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return publicClassExtendingFromPrivateModuleClass;
     }(privateModule.publicClassInPrivateModule));
@@ -189,24 +183,21 @@ var privateModule;
     var privateClassExtendingPublicClassInModule = (function (_super) {
         __extends(privateClassExtendingPublicClassInModule, _super);
         function privateClassExtendingPublicClassInModule() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return privateClassExtendingPublicClassInModule;
     }(publicClassInPrivateModule));
     var privateClassExtendingPrivateClassInModule = (function (_super) {
         __extends(privateClassExtendingPrivateClassInModule, _super);
         function privateClassExtendingPrivateClassInModule() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return privateClassExtendingPrivateClassInModule;
     }(privateClassInPrivateModule));
     var publicClassExtendingPublicClassInModule = (function (_super) {
         __extends(publicClassExtendingPublicClassInModule, _super);
         function publicClassExtendingPublicClassInModule() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return publicClassExtendingPublicClassInModule;
     }(publicClassInPrivateModule));
@@ -214,8 +205,7 @@ var privateModule;
     var publicClassExtendingPrivateClassInModule = (function (_super) {
         __extends(publicClassExtendingPrivateClassInModule, _super);
         function publicClassExtendingPrivateClassInModule() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return publicClassExtendingPrivateClassInModule;
     }(privateClassInPrivateModule));
@@ -223,16 +213,14 @@ var privateModule;
     var privateClassExtendingFromPrivateModuleClass = (function (_super) {
         __extends(privateClassExtendingFromPrivateModuleClass, _super);
         function privateClassExtendingFromPrivateModuleClass() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return privateClassExtendingFromPrivateModuleClass;
     }(privateModule.publicClassInPrivateModule));
     var publicClassExtendingFromPrivateModuleClass = (function (_super) {
         __extends(publicClassExtendingFromPrivateModuleClass, _super);
         function publicClassExtendingFromPrivateModuleClass() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return publicClassExtendingFromPrivateModuleClass;
     }(privateModule.publicClassInPrivateModule));
@@ -254,24 +242,21 @@ var privateClass = (function () {
 var privateClassExtendingPublicClass = (function (_super) {
     __extends(privateClassExtendingPublicClass, _super);
     function privateClassExtendingPublicClass() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return privateClassExtendingPublicClass;
 }(publicClass));
 var privateClassExtendingPrivateClassInModule = (function (_super) {
     __extends(privateClassExtendingPrivateClassInModule, _super);
     function privateClassExtendingPrivateClassInModule() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return privateClassExtendingPrivateClassInModule;
 }(privateClass));
 var publicClassExtendingPublicClass = (function (_super) {
     __extends(publicClassExtendingPublicClass, _super);
     function publicClassExtendingPublicClass() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return publicClassExtendingPublicClass;
 }(publicClass));
@@ -279,8 +264,7 @@ exports.publicClassExtendingPublicClass = publicClassExtendingPublicClass;
 var publicClassExtendingPrivateClass = (function (_super) {
     __extends(publicClassExtendingPrivateClass, _super);
     function publicClassExtendingPrivateClass() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return publicClassExtendingPrivateClass;
 }(privateClass));
@@ -288,16 +272,14 @@ exports.publicClassExtendingPrivateClass = publicClassExtendingPrivateClass;
 var privateClassExtendingFromPrivateModuleClass = (function (_super) {
     __extends(privateClassExtendingFromPrivateModuleClass, _super);
     function privateClassExtendingFromPrivateModuleClass() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return privateClassExtendingFromPrivateModuleClass;
 }(privateModule.publicClassInPrivateModule));
 var publicClassExtendingFromPrivateModuleClass = (function (_super) {
     __extends(publicClassExtendingFromPrivateModuleClass, _super);
     function publicClassExtendingFromPrivateModuleClass() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return publicClassExtendingFromPrivateModuleClass;
 }(privateModule.publicClassInPrivateModule));
@@ -326,24 +308,21 @@ var publicModuleInGlobal;
     var privateClassExtendingPublicClassInModule = (function (_super) {
         __extends(privateClassExtendingPublicClassInModule, _super);
         function privateClassExtendingPublicClassInModule() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return privateClassExtendingPublicClassInModule;
     }(publicClassInPublicModule));
     var privateClassExtendingPrivateClassInModule = (function (_super) {
         __extends(privateClassExtendingPrivateClassInModule, _super);
         function privateClassExtendingPrivateClassInModule() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return privateClassExtendingPrivateClassInModule;
     }(privateClassInPublicModule));
     var publicClassExtendingPublicClassInModule = (function (_super) {
         __extends(publicClassExtendingPublicClassInModule, _super);
         function publicClassExtendingPublicClassInModule() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return publicClassExtendingPublicClassInModule;
     }(publicClassInPublicModule));
@@ -351,8 +330,7 @@ var publicModuleInGlobal;
     var publicClassExtendingPrivateClassInModule = (function (_super) {
         __extends(publicClassExtendingPrivateClassInModule, _super);
         function publicClassExtendingPrivateClassInModule() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return publicClassExtendingPrivateClassInModule;
     }(privateClassInPublicModule));
@@ -366,8 +344,7 @@ var publicClassInGlobal = (function () {
 var publicClassExtendingPublicClassInGlobal = (function (_super) {
     __extends(publicClassExtendingPublicClassInGlobal, _super);
     function publicClassExtendingPublicClassInGlobal() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return publicClassExtendingPublicClassInGlobal;
 }(publicClassInGlobal));
diff --git a/tests/baselines/reference/privacyGloClass.js b/tests/baselines/reference/privacyGloClass.js
index 481a3921921..fa769a606ae 100644
--- a/tests/baselines/reference/privacyGloClass.js
+++ b/tests/baselines/reference/privacyGloClass.js
@@ -84,24 +84,21 @@ var m1;
     var m1_C1_private = (function (_super) {
         __extends(m1_C1_private, _super);
         function m1_C1_private() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return m1_C1_private;
     }(m1_c_public));
     var m1_C2_private = (function (_super) {
         __extends(m1_C2_private, _super);
         function m1_C2_private() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return m1_C2_private;
     }(m1_c_private));
     var m1_C3_public = (function (_super) {
         __extends(m1_C3_public, _super);
         function m1_C3_public() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return m1_C3_public;
     }(m1_c_public));
@@ -109,8 +106,7 @@ var m1;
     var m1_C4_public = (function (_super) {
         __extends(m1_C4_public, _super);
         function m1_C4_public() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return m1_C4_public;
     }(m1_c_private));
@@ -140,24 +136,21 @@ var m1;
     var m1_C9_private = (function (_super) {
         __extends(m1_C9_private, _super);
         function m1_C9_private() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return m1_C9_private;
     }(m1_c_public));
     var m1_C10_private = (function (_super) {
         __extends(m1_C10_private, _super);
         function m1_C10_private() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return m1_C10_private;
     }(m1_c_private));
     var m1_C11_public = (function (_super) {
         __extends(m1_C11_public, _super);
         function m1_C11_public() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return m1_C11_public;
     }(m1_c_public));
@@ -165,8 +158,7 @@ var m1;
     var m1_C12_public = (function (_super) {
         __extends(m1_C12_public, _super);
         function m1_C12_public() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return m1_C12_public;
     }(m1_c_private));
@@ -182,8 +174,7 @@ var glo_c_public = (function () {
 var glo_C3_public = (function (_super) {
     __extends(glo_C3_public, _super);
     function glo_C3_public() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return glo_C3_public;
 }(glo_c_public));
@@ -195,8 +186,7 @@ var glo_C7_public = (function () {
 var glo_C11_public = (function (_super) {
     __extends(glo_C11_public, _super);
     function glo_C11_public() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return glo_C11_public;
 }(glo_c_public));
diff --git a/tests/baselines/reference/privateAccessInSubclass1.js b/tests/baselines/reference/privateAccessInSubclass1.js
index ca432ee7ab7..21ff4793fb3 100644
--- a/tests/baselines/reference/privateAccessInSubclass1.js
+++ b/tests/baselines/reference/privateAccessInSubclass1.js
@@ -23,8 +23,7 @@ var Base = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     D.prototype.myMethod = function () {
         this.options;
diff --git a/tests/baselines/reference/privateProtectedMembersAreNotAccessibleDestructuring.js b/tests/baselines/reference/privateProtectedMembersAreNotAccessibleDestructuring.js
index 8b516a5a19c..b732661edfc 100644
--- a/tests/baselines/reference/privateProtectedMembersAreNotAccessibleDestructuring.js
+++ b/tests/baselines/reference/privateProtectedMembersAreNotAccessibleDestructuring.js
@@ -40,8 +40,7 @@ var K = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     C.prototype.m2 = function () {
         var a = this.priv; // error
diff --git a/tests/baselines/reference/privateStaticNotAccessibleInClodule2.js b/tests/baselines/reference/privateStaticNotAccessibleInClodule2.js
index 44adec751bf..11959f2f174 100644
--- a/tests/baselines/reference/privateStaticNotAccessibleInClodule2.js
+++ b/tests/baselines/reference/privateStaticNotAccessibleInClodule2.js
@@ -29,8 +29,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/project/privacyCheckOnImportedModuleDeclarationsInsideModule/amd/testGlo.js b/tests/baselines/reference/project/privacyCheckOnImportedModuleDeclarationsInsideModule/amd/testGlo.js
index ed9768b06c2..99a4842f636 100644
--- a/tests/baselines/reference/project/privacyCheckOnImportedModuleDeclarationsInsideModule/amd/testGlo.js
+++ b/tests/baselines/reference/project/privacyCheckOnImportedModuleDeclarationsInsideModule/amd/testGlo.js
@@ -14,8 +14,7 @@ var m2;
     var class1 = (function (_super) {
         __extends(class1, _super);
         function class1() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return class1;
     }(m2.mExported.me.class1));
@@ -28,8 +27,7 @@ var m2;
     var class2 = (function (_super) {
         __extends(class2, _super);
         function class2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return class2;
     }(m2.mExported.me.class1));
@@ -42,8 +40,7 @@ var m2;
     var class3 = (function (_super) {
         __extends(class3, _super);
         function class3() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return class3;
     }(mNonExported.mne.class1));
@@ -56,8 +53,7 @@ var m2;
     var class4 = (function (_super) {
         __extends(class4, _super);
         function class4() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return class4;
     }(mNonExported.mne.class1));
diff --git a/tests/baselines/reference/project/privacyCheckOnImportedModuleDeclarationsInsideModule/node/testGlo.js b/tests/baselines/reference/project/privacyCheckOnImportedModuleDeclarationsInsideModule/node/testGlo.js
index ed9768b06c2..99a4842f636 100644
--- a/tests/baselines/reference/project/privacyCheckOnImportedModuleDeclarationsInsideModule/node/testGlo.js
+++ b/tests/baselines/reference/project/privacyCheckOnImportedModuleDeclarationsInsideModule/node/testGlo.js
@@ -14,8 +14,7 @@ var m2;
     var class1 = (function (_super) {
         __extends(class1, _super);
         function class1() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return class1;
     }(m2.mExported.me.class1));
@@ -28,8 +27,7 @@ var m2;
     var class2 = (function (_super) {
         __extends(class2, _super);
         function class2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return class2;
     }(m2.mExported.me.class1));
@@ -42,8 +40,7 @@ var m2;
     var class3 = (function (_super) {
         __extends(class3, _super);
         function class3() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return class3;
     }(mNonExported.mne.class1));
@@ -56,8 +53,7 @@ var m2;
     var class4 = (function (_super) {
         __extends(class4, _super);
         function class4() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return class4;
     }(mNonExported.mne.class1));
diff --git a/tests/baselines/reference/project/prologueEmit/amd/out.js b/tests/baselines/reference/project/prologueEmit/amd/out.js
index deb73448794..7ee160b82ef 100644
--- a/tests/baselines/reference/project/prologueEmit/amd/out.js
+++ b/tests/baselines/reference/project/prologueEmit/amd/out.js
@@ -18,8 +18,7 @@ var m;
     var child = (function (_super) {
         __extends(child, _super);
         function child() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return child;
     }(base));
diff --git a/tests/baselines/reference/project/prologueEmit/node/out.js b/tests/baselines/reference/project/prologueEmit/node/out.js
index deb73448794..7ee160b82ef 100644
--- a/tests/baselines/reference/project/prologueEmit/node/out.js
+++ b/tests/baselines/reference/project/prologueEmit/node/out.js
@@ -18,8 +18,7 @@ var m;
     var child = (function (_super) {
         __extends(child, _super);
         function child() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return child;
     }(base));
diff --git a/tests/baselines/reference/project/quotesInFileAndDirectoryNames/amd/m'ain.js b/tests/baselines/reference/project/quotesInFileAndDirectoryNames/amd/m'ain.js
index b5147a28919..b793b07534c 100644
--- a/tests/baselines/reference/project/quotesInFileAndDirectoryNames/amd/m'ain.js
+++ b/tests/baselines/reference/project/quotesInFileAndDirectoryNames/amd/m'ain.js
@@ -7,8 +7,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var ClassC = (function (_super) {
     __extends(ClassC, _super);
     function ClassC() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return ClassC;
 }(test.ClassA));
diff --git a/tests/baselines/reference/project/quotesInFileAndDirectoryNames/node/m'ain.js b/tests/baselines/reference/project/quotesInFileAndDirectoryNames/node/m'ain.js
index b5147a28919..b793b07534c 100644
--- a/tests/baselines/reference/project/quotesInFileAndDirectoryNames/node/m'ain.js
+++ b/tests/baselines/reference/project/quotesInFileAndDirectoryNames/node/m'ain.js
@@ -7,8 +7,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var ClassC = (function (_super) {
     __extends(ClassC, _super);
     function ClassC() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return ClassC;
 }(test.ClassA));
diff --git a/tests/baselines/reference/propertiesAndIndexers.js b/tests/baselines/reference/propertiesAndIndexers.js
index a22f9663754..dff86f3954e 100644
--- a/tests/baselines/reference/propertiesAndIndexers.js
+++ b/tests/baselines/reference/propertiesAndIndexers.js
@@ -65,8 +65,7 @@ var P = (function () {
 var Q = (function (_super) {
     __extends(Q, _super);
     function Q() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Q;
 }(P));
diff --git a/tests/baselines/reference/propertyAccess.js b/tests/baselines/reference/propertyAccess.js
index 31b90bcf7ac..0a4c9082a21 100644
--- a/tests/baselines/reference/propertyAccess.js
+++ b/tests/baselines/reference/propertyAccess.js
@@ -164,8 +164,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
diff --git a/tests/baselines/reference/propertyAccessOnTypeParameterWithConstraints2.js b/tests/baselines/reference/propertyAccessOnTypeParameterWithConstraints2.js
index c570642a1ba..d36d7e27efe 100644
--- a/tests/baselines/reference/propertyAccessOnTypeParameterWithConstraints2.js
+++ b/tests/baselines/reference/propertyAccessOnTypeParameterWithConstraints2.js
@@ -97,8 +97,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     B.prototype.bar = function () {
         return '';
diff --git a/tests/baselines/reference/propertyAccessOnTypeParameterWithConstraints3.js b/tests/baselines/reference/propertyAccessOnTypeParameterWithConstraints3.js
index aebdc2c3ce3..4aedfe12b04 100644
--- a/tests/baselines/reference/propertyAccessOnTypeParameterWithConstraints3.js
+++ b/tests/baselines/reference/propertyAccessOnTypeParameterWithConstraints3.js
@@ -72,8 +72,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     B.prototype.bar = function () {
         return '';
diff --git a/tests/baselines/reference/propertyAccessOnTypeParameterWithConstraints5.js b/tests/baselines/reference/propertyAccessOnTypeParameterWithConstraints5.js
index 442ae29e278..3cb14438141 100644
--- a/tests/baselines/reference/propertyAccessOnTypeParameterWithConstraints5.js
+++ b/tests/baselines/reference/propertyAccessOnTypeParameterWithConstraints5.js
@@ -59,8 +59,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     B.prototype.bar = function () {
         return '';
diff --git a/tests/baselines/reference/protectedClassPropertyAccessibleWithinNestedSubclass.js b/tests/baselines/reference/protectedClassPropertyAccessibleWithinNestedSubclass.js
index 40a1365b7e1..429dfdf6b14 100644
--- a/tests/baselines/reference/protectedClassPropertyAccessibleWithinNestedSubclass.js
+++ b/tests/baselines/reference/protectedClassPropertyAccessibleWithinNestedSubclass.js
@@ -52,8 +52,7 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Object.defineProperty(C.prototype, "y", {
         get: function () { return this.x; },
@@ -94,8 +93,7 @@ var C = (function (_super) {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return E;
 }(C));
diff --git a/tests/baselines/reference/protectedClassPropertyAccessibleWithinNestedSubclass1.js b/tests/baselines/reference/protectedClassPropertyAccessibleWithinNestedSubclass1.js
index e6c768a6759..0571b85ea9e 100644
--- a/tests/baselines/reference/protectedClassPropertyAccessibleWithinNestedSubclass1.js
+++ b/tests/baselines/reference/protectedClassPropertyAccessibleWithinNestedSubclass1.js
@@ -147,8 +147,7 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived1.prototype.method1 = function () {
         var B = (function () {
@@ -174,8 +173,7 @@ var Derived1 = (function (_super) {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived2.prototype.method2 = function () {
         var C = (function () {
@@ -201,8 +199,7 @@ var Derived2 = (function (_super) {
 var Derived3 = (function (_super) {
     __extends(Derived3, _super);
     function Derived3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived3.prototype.method3 = function () {
         var D = (function () {
@@ -228,8 +225,7 @@ var Derived3 = (function (_super) {
 var Derived4 = (function (_super) {
     __extends(Derived4, _super);
     function Derived4() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived4.prototype.method4 = function () {
         var E = (function () {
diff --git a/tests/baselines/reference/protectedClassPropertyAccessibleWithinSubclass.js b/tests/baselines/reference/protectedClassPropertyAccessibleWithinSubclass.js
index 3f46b69ecf3..a10b39b402e 100644
--- a/tests/baselines/reference/protectedClassPropertyAccessibleWithinSubclass.js
+++ b/tests/baselines/reference/protectedClassPropertyAccessibleWithinSubclass.js
@@ -34,8 +34,7 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Object.defineProperty(C.prototype, "y", {
         get: function () { return this.x; },
diff --git a/tests/baselines/reference/protectedClassPropertyAccessibleWithinSubclass2.js b/tests/baselines/reference/protectedClassPropertyAccessibleWithinSubclass2.js
index 44a4fbdf284..a404b8049bc 100644
--- a/tests/baselines/reference/protectedClassPropertyAccessibleWithinSubclass2.js
+++ b/tests/baselines/reference/protectedClassPropertyAccessibleWithinSubclass2.js
@@ -120,8 +120,7 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived1.prototype.method1 = function () {
         var b;
@@ -140,8 +139,7 @@ var Derived1 = (function (_super) {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived2.prototype.method2 = function () {
         var b;
@@ -160,8 +158,7 @@ var Derived2 = (function (_super) {
 var Derived3 = (function (_super) {
     __extends(Derived3, _super);
     function Derived3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived3.prototype.method3 = function () {
         var b;
@@ -180,8 +177,7 @@ var Derived3 = (function (_super) {
 var Derived4 = (function (_super) {
     __extends(Derived4, _super);
     function Derived4() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived4.prototype.method4 = function () {
         var b;
diff --git a/tests/baselines/reference/protectedClassPropertyAccessibleWithinSubclass3.js b/tests/baselines/reference/protectedClassPropertyAccessibleWithinSubclass3.js
index 4cc09bac99d..7d449bdcbd4 100644
--- a/tests/baselines/reference/protectedClassPropertyAccessibleWithinSubclass3.js
+++ b/tests/baselines/reference/protectedClassPropertyAccessibleWithinSubclass3.js
@@ -30,8 +30,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived.prototype.method1 = function () {
         this.x; // OK, accessed within a subclass of the declaring class
diff --git a/tests/baselines/reference/protectedInstanceMemberAccessibility.js b/tests/baselines/reference/protectedInstanceMemberAccessibility.js
index 003e2f50e6f..3259d401270 100644
--- a/tests/baselines/reference/protectedInstanceMemberAccessibility.js
+++ b/tests/baselines/reference/protectedInstanceMemberAccessibility.js
@@ -61,8 +61,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     B.prototype.g = function () {
         var t1 = this.x;
@@ -94,8 +93,7 @@ var B = (function (_super) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/protectedMembers.js b/tests/baselines/reference/protectedMembers.js
index 984527b2c0d..46b4691dff7 100644
--- a/tests/baselines/reference/protectedMembers.js
+++ b/tests/baselines/reference/protectedMembers.js
@@ -137,8 +137,7 @@ var C1 = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     C2.prototype.f = function () {
         return _super.prototype.f.call(this) + this.x;
@@ -152,8 +151,7 @@ var C2 = (function (_super) {
 var C3 = (function (_super) {
     __extends(C3, _super);
     function C3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     C3.prototype.f = function () {
         return _super.prototype.f.call(this);
@@ -189,16 +187,14 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     C.foo = function (a, b, c, d, e) {
         a.x = 1; // Error, access must be through C or type derived from C
@@ -212,8 +208,7 @@ var C = (function (_super) {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(C));
@@ -244,8 +239,7 @@ var A2 = (function () {
 var B2 = (function (_super) {
     __extends(B2, _super);
     function B2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B2;
 }(A2));
@@ -258,8 +252,7 @@ var A3 = (function () {
 var B3 = (function (_super) {
     __extends(B3, _super);
     function B3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B3;
 }(A3));
diff --git a/tests/baselines/reference/protectedStaticClassPropertyAccessibleWithinSubclass.js b/tests/baselines/reference/protectedStaticClassPropertyAccessibleWithinSubclass.js
index a272ad42fa1..ad1b1682aa7 100644
--- a/tests/baselines/reference/protectedStaticClassPropertyAccessibleWithinSubclass.js
+++ b/tests/baselines/reference/protectedStaticClassPropertyAccessibleWithinSubclass.js
@@ -63,8 +63,7 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived1.staticMethod1 = function () {
         Base.x; // OK, accessed within a class derived from their declaring class
@@ -77,8 +76,7 @@ var Derived1 = (function (_super) {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived2.staticMethod2 = function () {
         Base.x; // OK, accessed within a class derived from their declaring class
@@ -91,8 +89,7 @@ var Derived2 = (function (_super) {
 var Derived3 = (function (_super) {
     __extends(Derived3, _super);
     function Derived3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived3.staticMethod3 = function () {
         Base.x; // OK, accessed within a class derived from their declaring class
diff --git a/tests/baselines/reference/protectedStaticClassPropertyAccessibleWithinSubclass2.js b/tests/baselines/reference/protectedStaticClassPropertyAccessibleWithinSubclass2.js
index 2add5e7e154..a2346b8be40 100644
--- a/tests/baselines/reference/protectedStaticClassPropertyAccessibleWithinSubclass2.js
+++ b/tests/baselines/reference/protectedStaticClassPropertyAccessibleWithinSubclass2.js
@@ -38,8 +38,7 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived1.staticMethod1 = function () {
         this.x; // OK, accessed within a class derived from their declaring class
@@ -50,8 +49,7 @@ var Derived1 = (function (_super) {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived2.staticMethod3 = function () {
         this.x; // OK, accessed within a class derived from their declaring class
diff --git a/tests/baselines/reference/qualifiedName_entity-name-resolution-does-not-affect-class-heritage.js b/tests/baselines/reference/qualifiedName_entity-name-resolution-does-not-affect-class-heritage.js
index 225acf74bbe..a881eb55a18 100644
--- a/tests/baselines/reference/qualifiedName_entity-name-resolution-does-not-affect-class-heritage.js
+++ b/tests/baselines/reference/qualifiedName_entity-name-resolution-does-not-affect-class-heritage.js
@@ -19,8 +19,7 @@ var Alpha;
 var Beta = (function (_super) {
     __extends(Beta, _super);
     function Beta() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Beta;
 }(Alpha.x));
diff --git a/tests/baselines/reference/recursiveBaseCheck3.js b/tests/baselines/reference/recursiveBaseCheck3.js
index 5b3e829d2e6..250a9e0b618 100644
--- a/tests/baselines/reference/recursiveBaseCheck3.js
+++ b/tests/baselines/reference/recursiveBaseCheck3.js
@@ -13,16 +13,14 @@ var __extends = (this && this.__extends) || function (d, b) {
 var A = (function (_super) {
     __extends(A, _super);
     function A() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return A;
 }(C));
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/recursiveBaseCheck4.js b/tests/baselines/reference/recursiveBaseCheck4.js
index b515c7ab318..7f0c6b5f95d 100644
--- a/tests/baselines/reference/recursiveBaseCheck4.js
+++ b/tests/baselines/reference/recursiveBaseCheck4.js
@@ -11,8 +11,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var M = (function (_super) {
     __extends(M, _super);
     function M() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return M;
 }(M));
diff --git a/tests/baselines/reference/recursiveBaseCheck6.js b/tests/baselines/reference/recursiveBaseCheck6.js
index 1871eff20d4..53a608baeca 100644
--- a/tests/baselines/reference/recursiveBaseCheck6.js
+++ b/tests/baselines/reference/recursiveBaseCheck6.js
@@ -11,8 +11,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var S18 = (function (_super) {
     __extends(S18, _super);
     function S18() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return S18;
 }(S18));
diff --git a/tests/baselines/reference/recursiveBaseConstructorCreation1.js b/tests/baselines/reference/recursiveBaseConstructorCreation1.js
index c2f884aa8e4..344750974cb 100644
--- a/tests/baselines/reference/recursiveBaseConstructorCreation1.js
+++ b/tests/baselines/reference/recursiveBaseConstructorCreation1.js
@@ -21,8 +21,7 @@ var C1 = (function () {
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }(C1));
diff --git a/tests/baselines/reference/recursiveClassInstantiationsWithDefaultConstructors.js b/tests/baselines/reference/recursiveClassInstantiationsWithDefaultConstructors.js
index f84c7ad3dae..34aa110b7ee 100644
--- a/tests/baselines/reference/recursiveClassInstantiationsWithDefaultConstructors.js
+++ b/tests/baselines/reference/recursiveClassInstantiationsWithDefaultConstructors.js
@@ -28,8 +28,7 @@ var TypeScript2;
     var MemberNameArray = (function (_super) {
         __extends(MemberNameArray, _super);
         function MemberNameArray() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return MemberNameArray;
     }(MemberName));
diff --git a/tests/baselines/reference/recursiveClassReferenceTest.js b/tests/baselines/reference/recursiveClassReferenceTest.js
index 2baa854e462..4c88b778226 100644
--- a/tests/baselines/reference/recursiveClassReferenceTest.js
+++ b/tests/baselines/reference/recursiveClassReferenceTest.js
@@ -190,8 +190,7 @@ var Sample;
                 var Mode = (function (_super) {
                     __extends(Mode, _super);
                     function Mode() {
-                        var _this = _super.apply(this, arguments) || this;
-                        return _this;
+                        return _super.apply(this, arguments) || this;
                     }
                     // scenario 2
                     Mode.prototype.getInitialState = function () {
diff --git a/tests/baselines/reference/recursiveClassReferenceTest.js.map b/tests/baselines/reference/recursiveClassReferenceTest.js.map
index 56c0fc4e6eb..bd22ec33898 100644
--- a/tests/baselines/reference/recursiveClassReferenceTest.js.map
+++ b/tests/baselines/reference/recursiveClassReferenceTest.js.map
@@ -1,2 +1,2 @@
 //// [recursiveClassReferenceTest.js.map]
-{"version":3,"file":"recursiveClassReferenceTest.js","sourceRoot":"","sources":["recursiveClassReferenceTest.ts"],"names":[],"mappings":"AAAA,iEAAiE;AACjE,0EAA0E;;;;;;AA8B1E,IAAO,MAAM,CAUZ;AAVD,WAAO,MAAM;IAAC,IAAA,OAAO,CAUpB;IAVa,WAAA,OAAO;QAAC,IAAA,KAAK,CAU1B;QAVqB,WAAA,OAAK;YAAC,IAAA,IAAI,CAU/B;YAV2B,WAAA,IAAI;gBAC/B;oBAAA;oBAQA,CAAC;oBANO,+BAAK,GAAZ,cAAiB,MAAM,CAAC,IAAI,CAAC,CAAC,CAAC;oBAExB,6BAAG,GAAV,UAAW,KAA6B;wBAEvC,MAAM,CAAC,IAAI,CAAC;oBACb,CAAC;oBACF,sBAAC;gBAAD,CAAC,AARD,IAQC;gBARY,oBAAe,kBAQ3B,CAAA;YACF,CAAC,EAV2B,IAAI,GAAJ,YAAI,KAAJ,YAAI,QAU/B;QAAD,CAAC,EAVqB,KAAK,GAAL,aAAK,KAAL,aAAK,QAU1B;IAAD,CAAC,EAVa,OAAO,GAAP,cAAO,KAAP,cAAO,QAUpB;AAAD,CAAC,EAVM,MAAM,KAAN,MAAM,QAUZ;AAED,IAAO,MAAM,CAoBZ;AApBD,WAAO,MAAM;IAAC,IAAA,KAAK,CAoBlB;IApBa,WAAA,KAAK;QAAC,IAAA,OAAO,CAoB1B;QApBmB,WAAA,OAAO;YAC1B;gBAKC,oBAAoB,SAAkC;oBAAlC,cAAS,GAAT,SAAS,CAAyB;oBAD9C,YAAO,GAAO,IAAI,CAAC;oBAEvB,aAAa;oBACb,SAAS,CAAC,SAAS,CAAC,WAAW,EAAE,IAAI,CAAC,CAAC;gBAC3C,CAAC;gBANM,wBAAG,GAAV,UAAW,MAAyC,IAAI,EAAE,CAAC,CAAC,IAAI,CAAC,CAAC,CAAC;oBAAA,MAAM,CAAC,MAAM,CAAC,IAAI,CAAC,CAAC;gBAAA,CAAC,CAAA,CAAC;gBAQlF,+BAAU,GAAjB;oBACC,MAAM,CAAC,OAAO,CAAC;gBAChB,CAAC;gBAEM,4BAAO,GAAd;gBAEA,CAAC;gBAEF,iBAAC;YAAD,CAAC,AAlBD,IAkBC;YAlBY,kBAAU,aAkBtB,CAAA;QACF,CAAC,EApBmB,OAAO,GAAP,aAAO,KAAP,aAAO,QAoB1B;IAAD,CAAC,EApBa,KAAK,GAAL,YAAK,KAAL,YAAK,QAoBlB;AAAD,CAAC,EApBM,MAAM,KAAN,MAAM,QAoBZ;AAGD;IAAA;IAAuF,CAAC;IAA3C,sCAAe,GAAtB,cAAmC,MAAM,CAAC,IAAI,CAAC,CAAA,CAAC;IAAC,mBAAC;AAAD,CAAC,AAAxF,IAAwF;AASxF,IAAO,MAAM,CAwBZ;AAxBD,WAAO,MAAM;IAAC,IAAA,KAAK,CAwBlB;IAxBa,WAAA,KAAK;QAAC,IAAA,SAAS,CAwB5B;QAxBmB,WAAA,SAAS;YAAC,IAAA,SAAS,CAwBtC;YAxB6B,WAAA,SAAS;gBAEtC;oBACO,eAAoB,IAAW;wBAAX,SAAI,GAAJ,IAAI,CAAO;oBAAI,CAAC;oBACnC,qBAAK,GAAZ;wBACC,MAAM,CAAC,IAAI,CAAC;oBACb,CAAC;oBAEM,sBAAM,GAAb,UAAc,KAAY;wBACzB,MAAM,CAAC,IAAI,KAAK,KAAK,CAAC;oBACvB,CAAC;oBAEM,uBAAO,GAAd,cAA0B,MAAM,CAAC,IAAI,CAAC,CAAC,CAAC;oBACzC,YAAC;gBAAD,CAAC,AAXD,IAWC;gBAXY,eAAK,QAWjB,CAAA;gBAED;oBAA0B,wBAAY;oBAAtC;wBAA0B,kDAAY;;oBAQtC,CAAC;oBANA,aAAa;oBACN,8BAAe,GAAtB;wBACC,MAAM,CAAC,IAAI,KAAK,CAAC,IAAI,CAAC,CAAC;oBACxB,CAAC;oBAGF,WAAC;gBAAD,CAAC,AARD,CAA0B,YAAY,GAQrC;gBARY,cAAI,OAQhB,CAAA;YACF,CAAC,EAxB6B,SAAS,GAAT,mBAAS,KAAT,mBAAS,QAwBtC;QAAD,CAAC,EAxBmB,SAAS,GAAT,eAAS,KAAT,eAAS,QAwB5B;IAAD,CAAC,EAxBa,KAAK,GAAL,YAAK,KAAL,YAAK,QAwBlB;AAAD,CAAC,EAxBM,MAAM,KAAN,MAAM,QAwBZ"}
\ No newline at end of file
+{"version":3,"file":"recursiveClassReferenceTest.js","sourceRoot":"","sources":["recursiveClassReferenceTest.ts"],"names":[],"mappings":"AAAA,iEAAiE;AACjE,0EAA0E;;;;;;AA8B1E,IAAO,MAAM,CAUZ;AAVD,WAAO,MAAM;IAAC,IAAA,OAAO,CAUpB;IAVa,WAAA,OAAO;QAAC,IAAA,KAAK,CAU1B;QAVqB,WAAA,OAAK;YAAC,IAAA,IAAI,CAU/B;YAV2B,WAAA,IAAI;gBAC/B;oBAAA;oBAQA,CAAC;oBANO,+BAAK,GAAZ,cAAiB,MAAM,CAAC,IAAI,CAAC,CAAC,CAAC;oBAExB,6BAAG,GAAV,UAAW,KAA6B;wBAEvC,MAAM,CAAC,IAAI,CAAC;oBACb,CAAC;oBACF,sBAAC;gBAAD,CAAC,AARD,IAQC;gBARY,oBAAe,kBAQ3B,CAAA;YACF,CAAC,EAV2B,IAAI,GAAJ,YAAI,KAAJ,YAAI,QAU/B;QAAD,CAAC,EAVqB,KAAK,GAAL,aAAK,KAAL,aAAK,QAU1B;IAAD,CAAC,EAVa,OAAO,GAAP,cAAO,KAAP,cAAO,QAUpB;AAAD,CAAC,EAVM,MAAM,KAAN,MAAM,QAUZ;AAED,IAAO,MAAM,CAoBZ;AApBD,WAAO,MAAM;IAAC,IAAA,KAAK,CAoBlB;IApBa,WAAA,KAAK;QAAC,IAAA,OAAO,CAoB1B;QApBmB,WAAA,OAAO;YAC1B;gBAKC,oBAAoB,SAAkC;oBAAlC,cAAS,GAAT,SAAS,CAAyB;oBAD9C,YAAO,GAAO,IAAI,CAAC;oBAEvB,aAAa;oBACb,SAAS,CAAC,SAAS,CAAC,WAAW,EAAE,IAAI,CAAC,CAAC;gBAC3C,CAAC;gBANM,wBAAG,GAAV,UAAW,MAAyC,IAAI,EAAE,CAAC,CAAC,IAAI,CAAC,CAAC,CAAC;oBAAA,MAAM,CAAC,MAAM,CAAC,IAAI,CAAC,CAAC;gBAAA,CAAC,CAAA,CAAC;gBAQlF,+BAAU,GAAjB;oBACC,MAAM,CAAC,OAAO,CAAC;gBAChB,CAAC;gBAEM,4BAAO,GAAd;gBAEA,CAAC;gBAEF,iBAAC;YAAD,CAAC,AAlBD,IAkBC;YAlBY,kBAAU,aAkBtB,CAAA;QACF,CAAC,EApBmB,OAAO,GAAP,aAAO,KAAP,aAAO,QAoB1B;IAAD,CAAC,EApBa,KAAK,GAAL,YAAK,KAAL,YAAK,QAoBlB;AAAD,CAAC,EApBM,MAAM,KAAN,MAAM,QAoBZ;AAGD;IAAA;IAAuF,CAAC;IAA3C,sCAAe,GAAtB,cAAmC,MAAM,CAAC,IAAI,CAAC,CAAA,CAAC;IAAC,mBAAC;AAAD,CAAC,AAAxF,IAAwF;AASxF,IAAO,MAAM,CAwBZ;AAxBD,WAAO,MAAM;IAAC,IAAA,KAAK,CAwBlB;IAxBa,WAAA,KAAK;QAAC,IAAA,SAAS,CAwB5B;QAxBmB,WAAA,SAAS;YAAC,IAAA,SAAS,CAwBtC;YAxB6B,WAAA,SAAS;gBAEtC;oBACO,eAAoB,IAAW;wBAAX,SAAI,GAAJ,IAAI,CAAO;oBAAI,CAAC;oBACnC,qBAAK,GAAZ;wBACC,MAAM,CAAC,IAAI,CAAC;oBACb,CAAC;oBAEM,sBAAM,GAAb,UAAc,KAAY;wBACzB,MAAM,CAAC,IAAI,KAAK,KAAK,CAAC;oBACvB,CAAC;oBAEM,uBAAO,GAAd,cAA0B,MAAM,CAAC,IAAI,CAAC,CAAC,CAAC;oBACzC,YAAC;gBAAD,CAAC,AAXD,IAWC;gBAXY,eAAK,QAWjB,CAAA;gBAED;oBAA0B,wBAAY;oBAAtC;;oBAQA,CAAC;oBANA,aAAa;oBACN,8BAAe,GAAtB;wBACC,MAAM,CAAC,IAAI,KAAK,CAAC,IAAI,CAAC,CAAC;oBACxB,CAAC;oBAGF,WAAC;gBAAD,CAAC,AARD,CAA0B,YAAY,GAQrC;gBARY,cAAI,OAQhB,CAAA;YACF,CAAC,EAxB6B,SAAS,GAAT,mBAAS,KAAT,mBAAS,QAwBtC;QAAD,CAAC,EAxBmB,SAAS,GAAT,eAAS,KAAT,eAAS,QAwB5B;IAAD,CAAC,EAxBa,KAAK,GAAL,YAAK,KAAL,YAAK,QAwBlB;AAAD,CAAC,EAxBM,MAAM,KAAN,MAAM,QAwBZ"}
\ No newline at end of file
diff --git a/tests/baselines/reference/recursiveClassReferenceTest.sourcemap.txt b/tests/baselines/reference/recursiveClassReferenceTest.sourcemap.txt
index 9656c078343..9dfefe4e1dc 100644
--- a/tests/baselines/reference/recursiveClassReferenceTest.sourcemap.txt
+++ b/tests/baselines/reference/recursiveClassReferenceTest.sourcemap.txt
@@ -1692,24 +1692,16 @@ sourceFile:recursiveClassReferenceTest.ts
 ---
 >>>                    function Mode() {
 1 >^^^^^^^^^^^^^^^^^^^^
-2 >                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
+2 >                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
 1 >
 1 >Emitted(87, 21) Source(91, 2) + SourceIndex(0)
 ---
->>>                        var _this = _super.apply(this, arguments) || this;
-1->^^^^^^^^^^^^^^^^^^^^^^^^
-2 >                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-1->export class Mode extends 
-2 >                        AbstractMode
-1->Emitted(88, 25) Source(91, 28) + SourceIndex(0)
-2 >Emitted(88, 75) Source(91, 40) + SourceIndex(0)
----
->>>                        return _this;
+>>>                        return _super.apply(this, arguments) || this;
 >>>                    }
-1 >^^^^^^^^^^^^^^^^^^^^
+1->^^^^^^^^^^^^^^^^^^^^
 2 >                    ^
 3 >                     ^^^^^^^^^^^^^->
-1 > {
+1->export class Mode extends AbstractMode {
   >
   >		// scenario 2
   >		public getInitialState(): IState {
@@ -1719,8 +1711,8 @@ sourceFile:recursiveClassReferenceTest.ts
   >
   >	
 2 >                    }
-1 >Emitted(90, 21) Source(99, 2) + SourceIndex(0)
-2 >Emitted(90, 22) Source(99, 3) + SourceIndex(0)
+1->Emitted(89, 21) Source(99, 2) + SourceIndex(0)
+2 >Emitted(89, 22) Source(99, 3) + SourceIndex(0)
 ---
 >>>                    // scenario 2
 1->^^^^^^^^^^^^^^^^^^^^
@@ -1728,8 +1720,8 @@ sourceFile:recursiveClassReferenceTest.ts
 3 >                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
 1->
 2 >                    // scenario 2
-1->Emitted(91, 21) Source(93, 3) + SourceIndex(0)
-2 >Emitted(91, 34) Source(93, 16) + SourceIndex(0)
+1->Emitted(90, 21) Source(93, 3) + SourceIndex(0)
+2 >Emitted(90, 34) Source(93, 16) + SourceIndex(0)
 ---
 >>>                    Mode.prototype.getInitialState = function () {
 1->^^^^^^^^^^^^^^^^^^^^
@@ -1739,9 +1731,9 @@ sourceFile:recursiveClassReferenceTest.ts
   >		public 
 2 >                    getInitialState
 3 >                                                  
-1->Emitted(92, 21) Source(94, 10) + SourceIndex(0)
-2 >Emitted(92, 51) Source(94, 25) + SourceIndex(0)
-3 >Emitted(92, 54) Source(94, 3) + SourceIndex(0)
+1->Emitted(91, 21) Source(94, 10) + SourceIndex(0)
+2 >Emitted(91, 51) Source(94, 25) + SourceIndex(0)
+3 >Emitted(91, 54) Source(94, 3) + SourceIndex(0)
 ---
 >>>                        return new State(self);
 1 >^^^^^^^^^^^^^^^^^^^^^^^^
@@ -1763,15 +1755,15 @@ sourceFile:recursiveClassReferenceTest.ts
 7 >                                         self
 8 >                                             )
 9 >                                              ;
-1 >Emitted(93, 25) Source(95, 4) + SourceIndex(0)
-2 >Emitted(93, 31) Source(95, 10) + SourceIndex(0)
-3 >Emitted(93, 32) Source(95, 11) + SourceIndex(0)
-4 >Emitted(93, 36) Source(95, 15) + SourceIndex(0)
-5 >Emitted(93, 41) Source(95, 20) + SourceIndex(0)
-6 >Emitted(93, 42) Source(95, 21) + SourceIndex(0)
-7 >Emitted(93, 46) Source(95, 25) + SourceIndex(0)
-8 >Emitted(93, 47) Source(95, 26) + SourceIndex(0)
-9 >Emitted(93, 48) Source(95, 27) + SourceIndex(0)
+1 >Emitted(92, 25) Source(95, 4) + SourceIndex(0)
+2 >Emitted(92, 31) Source(95, 10) + SourceIndex(0)
+3 >Emitted(92, 32) Source(95, 11) + SourceIndex(0)
+4 >Emitted(92, 36) Source(95, 15) + SourceIndex(0)
+5 >Emitted(92, 41) Source(95, 20) + SourceIndex(0)
+6 >Emitted(92, 42) Source(95, 21) + SourceIndex(0)
+7 >Emitted(92, 46) Source(95, 25) + SourceIndex(0)
+8 >Emitted(92, 47) Source(95, 26) + SourceIndex(0)
+9 >Emitted(92, 48) Source(95, 27) + SourceIndex(0)
 ---
 >>>                    };
 1 >^^^^^^^^^^^^^^^^^^^^
@@ -1780,8 +1772,8 @@ sourceFile:recursiveClassReferenceTest.ts
 1 >
   >		
 2 >                    }
-1 >Emitted(94, 21) Source(96, 3) + SourceIndex(0)
-2 >Emitted(94, 22) Source(96, 4) + SourceIndex(0)
+1 >Emitted(93, 21) Source(96, 3) + SourceIndex(0)
+2 >Emitted(93, 22) Source(96, 4) + SourceIndex(0)
 ---
 >>>                    return Mode;
 1->^^^^^^^^^^^^^^^^^^^^
@@ -1792,8 +1784,8 @@ sourceFile:recursiveClassReferenceTest.ts
   >
   >	
 2 >                    }
-1->Emitted(95, 21) Source(99, 2) + SourceIndex(0)
-2 >Emitted(95, 32) Source(99, 3) + SourceIndex(0)
+1->Emitted(94, 21) Source(99, 2) + SourceIndex(0)
+2 >Emitted(94, 32) Source(99, 3) + SourceIndex(0)
 ---
 >>>                }(AbstractMode));
 1->^^^^^^^^^^^^^^^^
@@ -1817,12 +1809,12 @@ sourceFile:recursiveClassReferenceTest.ts
   >                              
   >                              
   >                              	}
-1->Emitted(96, 17) Source(99, 2) + SourceIndex(0)
-2 >Emitted(96, 18) Source(99, 3) + SourceIndex(0)
-3 >Emitted(96, 18) Source(91, 2) + SourceIndex(0)
-4 >Emitted(96, 19) Source(91, 28) + SourceIndex(0)
-5 >Emitted(96, 31) Source(91, 40) + SourceIndex(0)
-6 >Emitted(96, 34) Source(99, 3) + SourceIndex(0)
+1->Emitted(95, 17) Source(99, 2) + SourceIndex(0)
+2 >Emitted(95, 18) Source(99, 3) + SourceIndex(0)
+3 >Emitted(95, 18) Source(91, 2) + SourceIndex(0)
+4 >Emitted(95, 19) Source(91, 28) + SourceIndex(0)
+5 >Emitted(95, 31) Source(91, 40) + SourceIndex(0)
+6 >Emitted(95, 34) Source(99, 3) + SourceIndex(0)
 ---
 >>>                PlainText.Mode = Mode;
 1->^^^^^^^^^^^^^^^^
@@ -1842,10 +1834,10 @@ sourceFile:recursiveClassReferenceTest.ts
   >                              
   >                              	}
 4 >                                     
-1->Emitted(97, 17) Source(91, 15) + SourceIndex(0)
-2 >Emitted(97, 31) Source(91, 19) + SourceIndex(0)
-3 >Emitted(97, 38) Source(99, 3) + SourceIndex(0)
-4 >Emitted(97, 39) Source(99, 3) + SourceIndex(0)
+1->Emitted(96, 17) Source(91, 15) + SourceIndex(0)
+2 >Emitted(96, 31) Source(91, 19) + SourceIndex(0)
+3 >Emitted(96, 38) Source(99, 3) + SourceIndex(0)
+4 >Emitted(96, 39) Source(99, 3) + SourceIndex(0)
 ---
 >>>            })(PlainText = Languages.PlainText || (Languages.PlainText = {}));
 1->^^^^^^^^^^^^
@@ -1891,15 +1883,15 @@ sourceFile:recursiveClassReferenceTest.ts
   >                                                                      
   >                                                                      	}
   >                                                                      }
-1->Emitted(98, 13) Source(100, 1) + SourceIndex(0)
-2 >Emitted(98, 14) Source(100, 2) + SourceIndex(0)
-3 >Emitted(98, 16) Source(76, 31) + SourceIndex(0)
-4 >Emitted(98, 25) Source(76, 40) + SourceIndex(0)
-5 >Emitted(98, 28) Source(76, 31) + SourceIndex(0)
-6 >Emitted(98, 47) Source(76, 40) + SourceIndex(0)
-7 >Emitted(98, 52) Source(76, 31) + SourceIndex(0)
-8 >Emitted(98, 71) Source(76, 40) + SourceIndex(0)
-9 >Emitted(98, 79) Source(100, 2) + SourceIndex(0)
+1->Emitted(97, 13) Source(100, 1) + SourceIndex(0)
+2 >Emitted(97, 14) Source(100, 2) + SourceIndex(0)
+3 >Emitted(97, 16) Source(76, 31) + SourceIndex(0)
+4 >Emitted(97, 25) Source(76, 40) + SourceIndex(0)
+5 >Emitted(97, 28) Source(76, 31) + SourceIndex(0)
+6 >Emitted(97, 47) Source(76, 40) + SourceIndex(0)
+7 >Emitted(97, 52) Source(76, 31) + SourceIndex(0)
+8 >Emitted(97, 71) Source(76, 40) + SourceIndex(0)
+9 >Emitted(97, 79) Source(100, 2) + SourceIndex(0)
 ---
 >>>        })(Languages = Thing.Languages || (Thing.Languages = {}));
 1 >^^^^^^^^
@@ -1944,15 +1936,15 @@ sourceFile:recursiveClassReferenceTest.ts
   >                                                          
   >                                                          	}
   >                                                          }
-1 >Emitted(99, 9) Source(100, 1) + SourceIndex(0)
-2 >Emitted(99, 10) Source(100, 2) + SourceIndex(0)
-3 >Emitted(99, 12) Source(76, 21) + SourceIndex(0)
-4 >Emitted(99, 21) Source(76, 30) + SourceIndex(0)
-5 >Emitted(99, 24) Source(76, 21) + SourceIndex(0)
-6 >Emitted(99, 39) Source(76, 30) + SourceIndex(0)
-7 >Emitted(99, 44) Source(76, 21) + SourceIndex(0)
-8 >Emitted(99, 59) Source(76, 30) + SourceIndex(0)
-9 >Emitted(99, 67) Source(100, 2) + SourceIndex(0)
+1 >Emitted(98, 9) Source(100, 1) + SourceIndex(0)
+2 >Emitted(98, 10) Source(100, 2) + SourceIndex(0)
+3 >Emitted(98, 12) Source(76, 21) + SourceIndex(0)
+4 >Emitted(98, 21) Source(76, 30) + SourceIndex(0)
+5 >Emitted(98, 24) Source(76, 21) + SourceIndex(0)
+6 >Emitted(98, 39) Source(76, 30) + SourceIndex(0)
+7 >Emitted(98, 44) Source(76, 21) + SourceIndex(0)
+8 >Emitted(98, 59) Source(76, 30) + SourceIndex(0)
+9 >Emitted(98, 67) Source(100, 2) + SourceIndex(0)
 ---
 >>>    })(Thing = Sample.Thing || (Sample.Thing = {}));
 1 >^^^^
@@ -1997,15 +1989,15 @@ sourceFile:recursiveClassReferenceTest.ts
   >                                            
   >                                            	}
   >                                            }
-1 >Emitted(100, 5) Source(100, 1) + SourceIndex(0)
-2 >Emitted(100, 6) Source(100, 2) + SourceIndex(0)
-3 >Emitted(100, 8) Source(76, 15) + SourceIndex(0)
-4 >Emitted(100, 13) Source(76, 20) + SourceIndex(0)
-5 >Emitted(100, 16) Source(76, 15) + SourceIndex(0)
-6 >Emitted(100, 28) Source(76, 20) + SourceIndex(0)
-7 >Emitted(100, 33) Source(76, 15) + SourceIndex(0)
-8 >Emitted(100, 45) Source(76, 20) + SourceIndex(0)
-9 >Emitted(100, 53) Source(100, 2) + SourceIndex(0)
+1 >Emitted(99, 5) Source(100, 1) + SourceIndex(0)
+2 >Emitted(99, 6) Source(100, 2) + SourceIndex(0)
+3 >Emitted(99, 8) Source(76, 15) + SourceIndex(0)
+4 >Emitted(99, 13) Source(76, 20) + SourceIndex(0)
+5 >Emitted(99, 16) Source(76, 15) + SourceIndex(0)
+6 >Emitted(99, 28) Source(76, 20) + SourceIndex(0)
+7 >Emitted(99, 33) Source(76, 15) + SourceIndex(0)
+8 >Emitted(99, 45) Source(76, 20) + SourceIndex(0)
+9 >Emitted(99, 53) Source(100, 2) + SourceIndex(0)
 ---
 >>>})(Sample || (Sample = {}));
 1 >
@@ -2047,12 +2039,12 @@ sourceFile:recursiveClassReferenceTest.ts
   >                    
   >                    	}
   >                    }
-1 >Emitted(101, 1) Source(100, 1) + SourceIndex(0)
-2 >Emitted(101, 2) Source(100, 2) + SourceIndex(0)
-3 >Emitted(101, 4) Source(76, 8) + SourceIndex(0)
-4 >Emitted(101, 10) Source(76, 14) + SourceIndex(0)
-5 >Emitted(101, 15) Source(76, 8) + SourceIndex(0)
-6 >Emitted(101, 21) Source(76, 14) + SourceIndex(0)
-7 >Emitted(101, 29) Source(100, 2) + SourceIndex(0)
+1 >Emitted(100, 1) Source(100, 1) + SourceIndex(0)
+2 >Emitted(100, 2) Source(100, 2) + SourceIndex(0)
+3 >Emitted(100, 4) Source(76, 8) + SourceIndex(0)
+4 >Emitted(100, 10) Source(76, 14) + SourceIndex(0)
+5 >Emitted(100, 15) Source(76, 8) + SourceIndex(0)
+6 >Emitted(100, 21) Source(76, 14) + SourceIndex(0)
+7 >Emitted(100, 29) Source(100, 2) + SourceIndex(0)
 ---
 >>>//# sourceMappingURL=recursiveClassReferenceTest.js.map
\ No newline at end of file
diff --git a/tests/baselines/reference/recursiveComplicatedClasses.js b/tests/baselines/reference/recursiveComplicatedClasses.js
index ea31184d856..8441ff9e15a 100644
--- a/tests/baselines/reference/recursiveComplicatedClasses.js
+++ b/tests/baselines/reference/recursiveComplicatedClasses.js
@@ -51,24 +51,21 @@ var Symbol = (function () {
 var InferenceSymbol = (function (_super) {
     __extends(InferenceSymbol, _super);
     function InferenceSymbol() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return InferenceSymbol;
 }(Symbol));
 var ParameterSymbol = (function (_super) {
     __extends(ParameterSymbol, _super);
     function ParameterSymbol() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return ParameterSymbol;
 }(InferenceSymbol));
 var TypeSymbol = (function (_super) {
     __extends(TypeSymbol, _super);
     function TypeSymbol() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return TypeSymbol;
 }(InferenceSymbol));
diff --git a/tests/baselines/reference/recursivelySpecializedConstructorDeclaration.js b/tests/baselines/reference/recursivelySpecializedConstructorDeclaration.js
index 72c97c30966..76224741e60 100644
--- a/tests/baselines/reference/recursivelySpecializedConstructorDeclaration.js
+++ b/tests/baselines/reference/recursivelySpecializedConstructorDeclaration.js
@@ -52,8 +52,7 @@ var MsPortal;
                 var ViewModel = (function (_super) {
                     __extends(ViewModel, _super);
                     function ViewModel() {
-                        var _this = _super.apply(this, arguments) || this;
-                        return _this;
+                        return _super.apply(this, arguments) || this;
                     }
                     return ViewModel;
                 }(ItemValue));
diff --git a/tests/baselines/reference/reexportClassDefinition.js b/tests/baselines/reference/reexportClassDefinition.js
index 95ce777e446..a75a90d4d86 100644
--- a/tests/baselines/reference/reexportClassDefinition.js
+++ b/tests/baselines/reference/reexportClassDefinition.js
@@ -42,8 +42,7 @@ var foo2 = require("./foo2");
 var x = (function (_super) {
     __extends(x, _super);
     function x() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return x;
 }(foo2.x));
diff --git a/tests/baselines/reference/resolvingClassDeclarationWhenInBaseTypeResolution.js b/tests/baselines/reference/resolvingClassDeclarationWhenInBaseTypeResolution.js
index d2ec8e168bf..615b0034caa 100644
--- a/tests/baselines/reference/resolvingClassDeclarationWhenInBaseTypeResolution.js
+++ b/tests/baselines/reference/resolvingClassDeclarationWhenInBaseTypeResolution.js
@@ -1030,8 +1030,7 @@ var rionegrensis;
     var caniventer = (function (_super) {
         __extends(caniventer, _super);
         function caniventer() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         caniventer.prototype.salomonseni = function () {
             var _this = this;
@@ -1069,8 +1068,7 @@ var rionegrensis;
     var veraecrucis = (function (_super) {
         __extends(veraecrucis, _super);
         function veraecrucis() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         veraecrucis.prototype.naso = function () {
             var _this = this;
@@ -1249,8 +1247,7 @@ var julianae;
     var oralis = (function (_super) {
         __extends(oralis, _super);
         function oralis() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         oralis.prototype.cepapi = function () {
             var _this = this;
@@ -1336,8 +1333,7 @@ var julianae;
     var sumatrana = (function (_super) {
         __extends(sumatrana, _super);
         function sumatrana() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         sumatrana.prototype.wolffsohni = function () {
             var _this = this;
@@ -1537,8 +1533,7 @@ var julianae;
     var durangae = (function (_super) {
         __extends(durangae, _super);
         function durangae() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         durangae.prototype.Californium = function () {
             var _this = this;
@@ -1612,8 +1607,7 @@ var Lanthanum;
     var nitidus = (function (_super) {
         __extends(nitidus, _super);
         function nitidus() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         nitidus.prototype.granatensis = function () {
             var _this = this;
@@ -1681,8 +1675,7 @@ var Lanthanum;
     var megalonyx = (function (_super) {
         __extends(megalonyx, _super);
         function megalonyx() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         megalonyx.prototype.phillipsii = function () {
             var _this = this;
@@ -1831,8 +1824,7 @@ var rendalli;
     var zuluensis = (function (_super) {
         __extends(zuluensis, _super);
         function zuluensis() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         zuluensis.prototype.telfairi = function () {
             var _this = this;
@@ -1990,8 +1982,7 @@ var rendalli;
     var crenulata = (function (_super) {
         __extends(crenulata, _super);
         function crenulata() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         crenulata.prototype.salvanius = function () {
             var _this = this;
@@ -2074,8 +2065,7 @@ var trivirgatus;
     var mixtus = (function (_super) {
         __extends(mixtus, _super);
         function mixtus() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         mixtus.prototype.ochrogaster = function () {
             var _this = this;
@@ -2317,8 +2307,7 @@ var ruatanica;
     var americanus = (function (_super) {
         __extends(americanus, _super);
         function americanus() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         americanus.prototype.nasoloi = function () {
             var _this = this;
@@ -2353,8 +2342,7 @@ var lavali;
     var wilsoni = (function (_super) {
         __extends(wilsoni, _super);
         function wilsoni() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         wilsoni.prototype.setiger = function () {
             var _this = this;
@@ -2446,8 +2434,7 @@ var lavali;
     var otion = (function (_super) {
         __extends(otion, _super);
         function otion() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         otion.prototype.bonaerensis = function () {
             var _this = this;
@@ -2611,8 +2598,7 @@ var lavali;
     var thaeleri = (function (_super) {
         __extends(thaeleri, _super);
         function thaeleri() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         thaeleri.prototype.coromandra = function () {
             var _this = this;
@@ -2668,8 +2654,7 @@ var lavali;
     var lepturus = (function (_super) {
         __extends(lepturus, _super);
         function lepturus() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         lepturus.prototype.ferrumequinum = function () {
             var _this = this;
@@ -2692,8 +2677,7 @@ var dogramacii;
     var robustulus = (function (_super) {
         __extends(robustulus, _super);
         function robustulus() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         robustulus.prototype.fossor = function () {
             var _this = this;
@@ -2908,8 +2892,7 @@ var lutreolus;
     var schlegeli = (function (_super) {
         __extends(schlegeli, _super);
         function schlegeli() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         schlegeli.prototype.mittendorfi = function () {
             var _this = this;
@@ -3136,8 +3119,7 @@ var panglima;
     var amphibius = (function (_super) {
         __extends(amphibius, _super);
         function amphibius() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         amphibius.prototype.bottegi = function () {
             var _this = this;
@@ -3181,8 +3163,7 @@ var panglima;
     var fundatus = (function (_super) {
         __extends(fundatus, _super);
         function fundatus() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         fundatus.prototype.crassulus = function () {
             var _this = this;
@@ -3208,8 +3189,7 @@ var panglima;
     var abidi = (function (_super) {
         __extends(abidi, _super);
         function abidi() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         abidi.prototype.greyii = function () {
             var _this = this;
@@ -3301,8 +3281,7 @@ var minutus;
     var himalayana = (function (_super) {
         __extends(himalayana, _super);
         function himalayana() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         himalayana.prototype.simoni = function () {
             var _this = this;
@@ -3385,8 +3364,7 @@ var caurinus;
     var mahaganus = (function (_super) {
         __extends(mahaganus, _super);
         function mahaganus() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         mahaganus.prototype.martiniquensis = function () {
             var _this = this;
@@ -3460,8 +3438,7 @@ var howi;
     var angulatus = (function (_super) {
         __extends(angulatus, _super);
         function angulatus() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         angulatus.prototype.pennatus = function () {
             var _this = this;
@@ -3544,8 +3521,7 @@ var sagitta;
     var walkeri = (function (_super) {
         __extends(walkeri, _super);
         function walkeri() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         walkeri.prototype.maracajuensis = function () {
             var _this = this;
@@ -3562,8 +3538,7 @@ var minutus;
     var inez = (function (_super) {
         __extends(inez, _super);
         function inez() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         inez.prototype.vexillaris = function () {
             var _this = this;
@@ -3580,8 +3555,7 @@ var macrorhinos;
     var konganensis = (function (_super) {
         __extends(konganensis, _super);
         function konganensis() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return konganensis;
     }(imperfecta.lasiurus));
@@ -3592,8 +3566,7 @@ var panamensis;
     var linulus = (function (_super) {
         __extends(linulus, _super);
         function linulus() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         linulus.prototype.goslingi = function () {
             var _this = this;
@@ -3745,8 +3718,7 @@ var samarensis;
     var pelurus = (function (_super) {
         __extends(pelurus, _super);
         function pelurus() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         pelurus.prototype.Palladium = function () {
             var _this = this;
@@ -3832,8 +3804,7 @@ var samarensis;
     var fuscus = (function (_super) {
         __extends(fuscus, _super);
         function fuscus() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         fuscus.prototype.planifrons = function () {
             var _this = this;
@@ -3994,8 +3965,7 @@ var sagitta;
     var leptoceros = (function (_super) {
         __extends(leptoceros, _super);
         function leptoceros() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         leptoceros.prototype.victus = function () {
             var _this = this;
@@ -4036,8 +4006,7 @@ var daubentonii;
     var nigricans = (function (_super) {
         __extends(nigricans, _super);
         function nigricans() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         nigricans.prototype.woosnami = function () {
             var _this = this;
@@ -4063,8 +4032,7 @@ var argurus;
     var pygmaea = (function (_super) {
         __extends(pygmaea, _super);
         function pygmaea() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         pygmaea.prototype.pajeros = function () {
             var _this = this;
@@ -4093,8 +4061,7 @@ var chrysaeolus;
     var sarasinorum = (function (_super) {
         __extends(sarasinorum, _super);
         function sarasinorum() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         sarasinorum.prototype.belzebul = function () {
             var _this = this;
@@ -4198,8 +4165,7 @@ var argurus;
     var oreas = (function (_super) {
         __extends(oreas, _super);
         function oreas() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         oreas.prototype.salamonis = function () {
             var _this = this;
@@ -4426,8 +4392,7 @@ var provocax;
     var melanoleuca = (function (_super) {
         __extends(melanoleuca, _super);
         function melanoleuca() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         melanoleuca.prototype.Neodymium = function () {
             var _this = this;
@@ -4471,8 +4436,7 @@ var howi;
     var marcanoi = (function (_super) {
         __extends(marcanoi, _super);
         function marcanoi() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         marcanoi.prototype.formosae = function () {
             var _this = this;
@@ -4879,8 +4843,7 @@ var gabriellae;
     var klossii = (function (_super) {
         __extends(klossii, _super);
         function klossii() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return klossii;
     }(imperfecta.lasiurus));
@@ -5083,8 +5046,7 @@ var imperfecta;
     var ciliolabrum = (function (_super) {
         __extends(ciliolabrum, _super);
         function ciliolabrum() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         ciliolabrum.prototype.leschenaultii = function () {
             var _this = this;
@@ -5146,8 +5108,7 @@ var petrophilus;
     var sodyi = (function (_super) {
         __extends(sodyi, _super);
         function sodyi() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         sodyi.prototype.saundersiae = function () {
             var _this = this;
@@ -5212,8 +5173,7 @@ var caurinus;
     var megaphyllus = (function (_super) {
         __extends(megaphyllus, _super);
         function megaphyllus() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         megaphyllus.prototype.montana = function () {
             var _this = this;
@@ -5386,8 +5346,7 @@ var lutreolus;
     var cor = (function (_super) {
         __extends(cor, _super);
         function cor() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         cor.prototype.antinorii = function () {
             var _this = this;
@@ -5479,8 +5438,7 @@ var argurus;
     var germaini = (function (_super) {
         __extends(germaini, _super);
         function germaini() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         germaini.prototype.sharpei = function () {
             var _this = this;
@@ -5578,8 +5536,7 @@ var dammermani;
     var melanops = (function (_super) {
         __extends(melanops, _super);
         function melanops() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         melanops.prototype.blarina = function () {
             var _this = this;
@@ -5668,8 +5625,7 @@ var argurus;
     var peninsulae = (function (_super) {
         __extends(peninsulae, _super);
         function peninsulae() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         peninsulae.prototype.aitkeni = function () {
             var _this = this;
@@ -5815,8 +5771,7 @@ var ruatanica;
     var Praseodymium = (function (_super) {
         __extends(Praseodymium, _super);
         function Praseodymium() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         Praseodymium.prototype.clara = function () {
             var _this = this;
@@ -5905,8 +5860,7 @@ var caurinus;
     var johorensis = (function (_super) {
         __extends(johorensis, _super);
         function johorensis() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         johorensis.prototype.maini = function () {
             var _this = this;
@@ -6034,8 +5988,7 @@ var caurinus;
     var psilurus = (function (_super) {
         __extends(psilurus, _super);
         function psilurus() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         psilurus.prototype.socialis = function () {
             var _this = this;
diff --git a/tests/baselines/reference/returnStatements.js b/tests/baselines/reference/returnStatements.js
index 659eea55689..f786e994963 100644
--- a/tests/baselines/reference/returnStatements.js
+++ b/tests/baselines/reference/returnStatements.js
@@ -48,8 +48,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/scopeCheckExtendedClassInsidePublicMethod2.js b/tests/baselines/reference/scopeCheckExtendedClassInsidePublicMethod2.js
index 02c81245445..1474f8ab29a 100644
--- a/tests/baselines/reference/scopeCheckExtendedClassInsidePublicMethod2.js
+++ b/tests/baselines/reference/scopeCheckExtendedClassInsidePublicMethod2.js
@@ -22,8 +22,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     D.prototype.c = function () {
         v = 1;
diff --git a/tests/baselines/reference/scopeCheckExtendedClassInsideStaticMethod1.js b/tests/baselines/reference/scopeCheckExtendedClassInsideStaticMethod1.js
index 781fd5ac6ee..0baf0187009 100644
--- a/tests/baselines/reference/scopeCheckExtendedClassInsideStaticMethod1.js
+++ b/tests/baselines/reference/scopeCheckExtendedClassInsideStaticMethod1.js
@@ -22,8 +22,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     D.c = function () {
         v = 1;
diff --git a/tests/baselines/reference/shadowPrivateMembers.js b/tests/baselines/reference/shadowPrivateMembers.js
index d7e1b69e274..4906814f7eb 100644
--- a/tests/baselines/reference/shadowPrivateMembers.js
+++ b/tests/baselines/reference/shadowPrivateMembers.js
@@ -18,8 +18,7 @@ var base = (function () {
 var derived = (function (_super) {
     __extends(derived, _super);
     function derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     derived.prototype.n = function () { };
     return derived;
diff --git a/tests/baselines/reference/specializedInheritedConstructors1.js b/tests/baselines/reference/specializedInheritedConstructors1.js
index 4f14cb6db97..f65f42941bf 100644
--- a/tests/baselines/reference/specializedInheritedConstructors1.js
+++ b/tests/baselines/reference/specializedInheritedConstructors1.js
@@ -36,8 +36,7 @@ var Model = (function () {
 var MyView = (function (_super) {
     __extends(MyView, _super);
     function MyView() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return MyView;
 }(View));
diff --git a/tests/baselines/reference/specializedOverloadWithRestParameters.js b/tests/baselines/reference/specializedOverloadWithRestParameters.js
index 3b909a80836..b76afaff08c 100644
--- a/tests/baselines/reference/specializedOverloadWithRestParameters.js
+++ b/tests/baselines/reference/specializedOverloadWithRestParameters.js
@@ -27,8 +27,7 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived1.prototype.bar = function () { };
     return Derived1;
diff --git a/tests/baselines/reference/staticFactory1.js b/tests/baselines/reference/staticFactory1.js
index d229c5330ba..de7588c3ebe 100644
--- a/tests/baselines/reference/staticFactory1.js
+++ b/tests/baselines/reference/staticFactory1.js
@@ -31,8 +31,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Derived.prototype.foo = function () { return 2; };
     return Derived;
diff --git a/tests/baselines/reference/staticMemberAccessOffDerivedType1.js b/tests/baselines/reference/staticMemberAccessOffDerivedType1.js
index a07bea081a9..7b8ca52b9a4 100644
--- a/tests/baselines/reference/staticMemberAccessOffDerivedType1.js
+++ b/tests/baselines/reference/staticMemberAccessOffDerivedType1.js
@@ -26,8 +26,7 @@ var SomeBase = (function () {
 var P = (function (_super) {
     __extends(P, _super);
     function P() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return P;
 }(SomeBase));
diff --git a/tests/baselines/reference/strictModeReservedWord.js b/tests/baselines/reference/strictModeReservedWord.js
index af01ca1716f..29715745890 100644
--- a/tests/baselines/reference/strictModeReservedWord.js
+++ b/tests/baselines/reference/strictModeReservedWord.js
@@ -48,8 +48,7 @@ function foo() {
     var myClass = (function (_super) {
         __extends(package, _super);
         function package() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return package;
     }(public));
diff --git a/tests/baselines/reference/strictModeReservedWordInClassDeclaration.js b/tests/baselines/reference/strictModeReservedWordInClassDeclaration.js
index 300d83b9bbc..1507e53d8cf 100644
--- a/tests/baselines/reference/strictModeReservedWordInClassDeclaration.js
+++ b/tests/baselines/reference/strictModeReservedWordInClassDeclaration.js
@@ -75,16 +75,14 @@ var F1 = (function () {
 var G = (function (_super) {
     __extends(G, _super);
     function G() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return G;
 }(package));
 var H = (function (_super) {
     __extends(H, _super);
     function H() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return H;
 }(package.A));
diff --git a/tests/baselines/reference/stringIndexerConstrainsPropertyDeclarations2.js b/tests/baselines/reference/stringIndexerConstrainsPropertyDeclarations2.js
index eb5052f51d7..b532df7b120 100644
--- a/tests/baselines/reference/stringIndexerConstrainsPropertyDeclarations2.js
+++ b/tests/baselines/reference/stringIndexerConstrainsPropertyDeclarations2.js
@@ -55,8 +55,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     B.prototype.bar = function () { return ''; };
     return B;
diff --git a/tests/baselines/reference/subtypesOfTypeParameter.js b/tests/baselines/reference/subtypesOfTypeParameter.js
index cbe42a510b3..a6606c5d559 100644
--- a/tests/baselines/reference/subtypesOfTypeParameter.js
+++ b/tests/baselines/reference/subtypesOfTypeParameter.js
@@ -120,8 +120,7 @@ var C3 = (function () {
 var D1 = (function (_super) {
     __extends(D1, _super);
     function D1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D1;
 }(C3));
diff --git a/tests/baselines/reference/subtypesOfTypeParameterWithConstraints.js b/tests/baselines/reference/subtypesOfTypeParameterWithConstraints.js
index 56800248393..82bcbf14ecc 100644
--- a/tests/baselines/reference/subtypesOfTypeParameterWithConstraints.js
+++ b/tests/baselines/reference/subtypesOfTypeParameterWithConstraints.js
@@ -182,32 +182,28 @@ var C3 = (function () {
 var D1 = (function (_super) {
     __extends(D1, _super);
     function D1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D1;
 }(C3));
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D2;
 }(C3));
 var D3 = (function (_super) {
     __extends(D3, _super);
     function D3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D3;
 }(C3));
 var D4 = (function (_super) {
     __extends(D4, _super);
     function D4() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D4;
 }(C3));
@@ -217,24 +213,21 @@ var D4 = (function (_super) {
 var D5 = (function (_super) {
     __extends(D5, _super);
     function D5() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D5;
 }(C3));
 var D6 = (function (_super) {
     __extends(D6, _super);
     function D6() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D6;
 }(C3));
 var D7 = (function (_super) {
     __extends(D7, _super);
     function D7() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D7;
 }(C3));
@@ -243,24 +236,21 @@ var D7 = (function (_super) {
 var D8 = (function (_super) {
     __extends(D8, _super);
     function D8() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D8;
 }(C3));
 var D9 = (function (_super) {
     __extends(D9, _super);
     function D9() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D9;
 }(C3));
 var D10 = (function (_super) {
     __extends(D10, _super);
     function D10() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D10;
 }(C3));
@@ -269,24 +259,21 @@ var D10 = (function (_super) {
 var D11 = (function (_super) {
     __extends(D11, _super);
     function D11() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D11;
 }(C3));
 var D12 = (function (_super) {
     __extends(D12, _super);
     function D12() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D12;
 }(C3));
 var D13 = (function (_super) {
     __extends(D13, _super);
     function D13() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D13;
 }(C3));
@@ -296,32 +283,28 @@ var D13 = (function (_super) {
 var D14 = (function (_super) {
     __extends(D14, _super);
     function D14() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D14;
 }(C3));
 var D15 = (function (_super) {
     __extends(D15, _super);
     function D15() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D15;
 }(C3));
 var D16 = (function (_super) {
     __extends(D16, _super);
     function D16() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D16;
 }(C3));
 var D17 = (function (_super) {
     __extends(D17, _super);
     function D17() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D17;
 }(C3));
@@ -330,32 +313,28 @@ var D17 = (function (_super) {
 var D18 = (function (_super) {
     __extends(D18, _super);
     function D18() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D18;
 }(C3));
 var D19 = (function (_super) {
     __extends(D19, _super);
     function D19() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D19;
 }(C3));
 var D20 = (function (_super) {
     __extends(D20, _super);
     function D20() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D20;
 }(C3));
 var D21 = (function (_super) {
     __extends(D21, _super);
     function D21() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D21;
 }(C3));
@@ -364,32 +343,28 @@ var D21 = (function (_super) {
 var D22 = (function (_super) {
     __extends(D22, _super);
     function D22() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D22;
 }(C3));
 var D23 = (function (_super) {
     __extends(D23, _super);
     function D23() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D23;
 }(C3));
 var D24 = (function (_super) {
     __extends(D24, _super);
     function D24() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D24;
 }(C3));
 var D25 = (function (_super) {
     __extends(D25, _super);
     function D25() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D25;
 }(C3));
@@ -398,32 +373,28 @@ var D25 = (function (_super) {
 var D26 = (function (_super) {
     __extends(D26, _super);
     function D26() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D26;
 }(C3));
 var D27 = (function (_super) {
     __extends(D27, _super);
     function D27() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D27;
 }(C3));
 var D28 = (function (_super) {
     __extends(D28, _super);
     function D28() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D28;
 }(C3));
 var D29 = (function (_super) {
     __extends(D29, _super);
     function D29() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D29;
 }(C3));
diff --git a/tests/baselines/reference/subtypesOfTypeParameterWithConstraints4.js b/tests/baselines/reference/subtypesOfTypeParameterWithConstraints4.js
index e4e35262d80..e0baced37a4 100644
--- a/tests/baselines/reference/subtypesOfTypeParameterWithConstraints4.js
+++ b/tests/baselines/reference/subtypesOfTypeParameterWithConstraints4.js
@@ -118,72 +118,63 @@ var B1 = (function () {
 var D1 = (function (_super) {
     __extends(D1, _super);
     function D1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D1;
 }(B1));
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D2;
 }(B1));
 var D3 = (function (_super) {
     __extends(D3, _super);
     function D3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D3;
 }(B1));
 var D4 = (function (_super) {
     __extends(D4, _super);
     function D4() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D4;
 }(B1));
 var D5 = (function (_super) {
     __extends(D5, _super);
     function D5() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D5;
 }(B1));
 var D6 = (function (_super) {
     __extends(D6, _super);
     function D6() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D6;
 }(B1));
 var D7 = (function (_super) {
     __extends(D7, _super);
     function D7() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D7;
 }(B1));
 var D8 = (function (_super) {
     __extends(D8, _super);
     function D8() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D8;
 }(B1));
 var D9 = (function (_super) {
     __extends(D9, _super);
     function D9() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D9;
 }(B1));
diff --git a/tests/baselines/reference/subtypesOfTypeParameterWithRecursiveConstraints.js b/tests/baselines/reference/subtypesOfTypeParameterWithRecursiveConstraints.js
index 0d1347cd33c..0b17fc07f24 100644
--- a/tests/baselines/reference/subtypesOfTypeParameterWithRecursiveConstraints.js
+++ b/tests/baselines/reference/subtypesOfTypeParameterWithRecursiveConstraints.js
@@ -217,72 +217,63 @@ var M1;
     var D1 = (function (_super) {
         __extends(D1, _super);
         function D1() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D1;
     }(Base));
     var D2 = (function (_super) {
         __extends(D2, _super);
         function D2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D2;
     }(Base));
     var D3 = (function (_super) {
         __extends(D3, _super);
         function D3() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D3;
     }(Base));
     var D4 = (function (_super) {
         __extends(D4, _super);
         function D4() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D4;
     }(Base));
     var D5 = (function (_super) {
         __extends(D5, _super);
         function D5() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D5;
     }(Base));
     var D6 = (function (_super) {
         __extends(D6, _super);
         function D6() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D6;
     }(Base));
     var D7 = (function (_super) {
         __extends(D7, _super);
         function D7() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D7;
     }(Base));
     var D8 = (function (_super) {
         __extends(D8, _super);
         function D8() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D8;
     }(Base));
     var D9 = (function (_super) {
         __extends(D9, _super);
         function D9() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D9;
     }(Base));
@@ -297,72 +288,63 @@ var M2;
     var D1 = (function (_super) {
         __extends(D1, _super);
         function D1() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D1;
     }(Base2));
     var D2 = (function (_super) {
         __extends(D2, _super);
         function D2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D2;
     }(Base2));
     var D3 = (function (_super) {
         __extends(D3, _super);
         function D3() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D3;
     }(Base2));
     var D4 = (function (_super) {
         __extends(D4, _super);
         function D4() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D4;
     }(Base2));
     var D5 = (function (_super) {
         __extends(D5, _super);
         function D5() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D5;
     }(Base2));
     var D6 = (function (_super) {
         __extends(D6, _super);
         function D6() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D6;
     }(Base2));
     var D7 = (function (_super) {
         __extends(D7, _super);
         function D7() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D7;
     }(Base2));
     var D8 = (function (_super) {
         __extends(D8, _super);
         function D8() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D8;
     }(Base2));
     var D9 = (function (_super) {
         __extends(D9, _super);
         function D9() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return D9;
     }(Base2));
diff --git a/tests/baselines/reference/subtypingTransitivity.js b/tests/baselines/reference/subtypingTransitivity.js
index 9ba7ac52df5..9c4c9011758 100644
--- a/tests/baselines/reference/subtypingTransitivity.js
+++ b/tests/baselines/reference/subtypingTransitivity.js
@@ -33,16 +33,14 @@ var B = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(B));
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D2;
 }(B));
diff --git a/tests/baselines/reference/subtypingWithCallSignatures2.js b/tests/baselines/reference/subtypingWithCallSignatures2.js
index d4cd66a5e0a..843a727c33e 100644
--- a/tests/baselines/reference/subtypingWithCallSignatures2.js
+++ b/tests/baselines/reference/subtypingWithCallSignatures2.js
@@ -187,24 +187,21 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/subtypingWithCallSignatures3.js b/tests/baselines/reference/subtypingWithCallSignatures3.js
index 93b1cbebd0a..a9e7d01aab6 100644
--- a/tests/baselines/reference/subtypingWithCallSignatures3.js
+++ b/tests/baselines/reference/subtypingWithCallSignatures3.js
@@ -136,24 +136,21 @@ var Errors;
     var Derived = (function (_super) {
         __extends(Derived, _super);
         function Derived() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Derived;
     }(Base));
     var Derived2 = (function (_super) {
         __extends(Derived2, _super);
         function Derived2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Derived2;
     }(Derived));
     var OtherDerived = (function (_super) {
         __extends(OtherDerived, _super);
         function OtherDerived() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return OtherDerived;
     }(Base));
diff --git a/tests/baselines/reference/subtypingWithCallSignatures4.js b/tests/baselines/reference/subtypingWithCallSignatures4.js
index 5cab9f1e7c4..94f549c62c1 100644
--- a/tests/baselines/reference/subtypingWithCallSignatures4.js
+++ b/tests/baselines/reference/subtypingWithCallSignatures4.js
@@ -126,24 +126,21 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/subtypingWithConstructSignatures2.js b/tests/baselines/reference/subtypingWithConstructSignatures2.js
index ec551f5f58c..1d12aeb945f 100644
--- a/tests/baselines/reference/subtypingWithConstructSignatures2.js
+++ b/tests/baselines/reference/subtypingWithConstructSignatures2.js
@@ -187,24 +187,21 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/subtypingWithConstructSignatures3.js b/tests/baselines/reference/subtypingWithConstructSignatures3.js
index ba833c31e7a..78582304cb8 100644
--- a/tests/baselines/reference/subtypingWithConstructSignatures3.js
+++ b/tests/baselines/reference/subtypingWithConstructSignatures3.js
@@ -138,24 +138,21 @@ var Errors;
     var Derived = (function (_super) {
         __extends(Derived, _super);
         function Derived() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Derived;
     }(Base));
     var Derived2 = (function (_super) {
         __extends(Derived2, _super);
         function Derived2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Derived2;
     }(Derived));
     var OtherDerived = (function (_super) {
         __extends(OtherDerived, _super);
         function OtherDerived() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return OtherDerived;
     }(Base));
diff --git a/tests/baselines/reference/subtypingWithConstructSignatures4.js b/tests/baselines/reference/subtypingWithConstructSignatures4.js
index 0b624fcbc51..17252fdb809 100644
--- a/tests/baselines/reference/subtypingWithConstructSignatures4.js
+++ b/tests/baselines/reference/subtypingWithConstructSignatures4.js
@@ -126,24 +126,21 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/subtypingWithConstructSignatures5.js b/tests/baselines/reference/subtypingWithConstructSignatures5.js
index 3d2d4d50d6e..a0561606393 100644
--- a/tests/baselines/reference/subtypingWithConstructSignatures5.js
+++ b/tests/baselines/reference/subtypingWithConstructSignatures5.js
@@ -64,24 +64,21 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/subtypingWithConstructSignatures6.js b/tests/baselines/reference/subtypingWithConstructSignatures6.js
index 1cec204ff87..c508781e089 100644
--- a/tests/baselines/reference/subtypingWithConstructSignatures6.js
+++ b/tests/baselines/reference/subtypingWithConstructSignatures6.js
@@ -67,24 +67,21 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived));
 var OtherDerived = (function (_super) {
     __extends(OtherDerived, _super);
     function OtherDerived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return OtherDerived;
 }(Base));
diff --git a/tests/baselines/reference/subtypingWithNumericIndexer.js b/tests/baselines/reference/subtypingWithNumericIndexer.js
index 2aa4d834395..3cf75dd83fd 100644
--- a/tests/baselines/reference/subtypingWithNumericIndexer.js
+++ b/tests/baselines/reference/subtypingWithNumericIndexer.js
@@ -54,16 +54,14 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
 var B2 = (function (_super) {
     __extends(B2, _super);
     function B2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B2;
 }(A));
@@ -77,32 +75,28 @@ var Generics;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(A));
     var B2 = (function (_super) {
         __extends(B2, _super);
         function B2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B2;
     }(A));
     var B3 = (function (_super) {
         __extends(B3, _super);
         function B3() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B3;
     }(A));
     var B4 = (function (_super) {
         __extends(B4, _super);
         function B4() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B4;
     }(A));
diff --git a/tests/baselines/reference/subtypingWithNumericIndexer3.js b/tests/baselines/reference/subtypingWithNumericIndexer3.js
index 60f463546c8..e9e8d39bf3c 100644
--- a/tests/baselines/reference/subtypingWithNumericIndexer3.js
+++ b/tests/baselines/reference/subtypingWithNumericIndexer3.js
@@ -58,16 +58,14 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
 var B2 = (function (_super) {
     __extends(B2, _super);
     function B2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B2;
 }(A));
@@ -81,40 +79,35 @@ var Generics;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(A));
     var B2 = (function (_super) {
         __extends(B2, _super);
         function B2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B2;
     }(A));
     var B3 = (function (_super) {
         __extends(B3, _super);
         function B3() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B3;
     }(A));
     var B4 = (function (_super) {
         __extends(B4, _super);
         function B4() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B4;
     }(A));
     var B5 = (function (_super) {
         __extends(B5, _super);
         function B5() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B5;
     }(A));
diff --git a/tests/baselines/reference/subtypingWithNumericIndexer4.js b/tests/baselines/reference/subtypingWithNumericIndexer4.js
index f40804bd55f..798e775083f 100644
--- a/tests/baselines/reference/subtypingWithNumericIndexer4.js
+++ b/tests/baselines/reference/subtypingWithNumericIndexer4.js
@@ -42,8 +42,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
@@ -57,16 +56,14 @@ var Generics;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(A));
     var B3 = (function (_super) {
         __extends(B3, _super);
         function B3() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B3;
     }(A));
diff --git a/tests/baselines/reference/subtypingWithObjectMembers.js b/tests/baselines/reference/subtypingWithObjectMembers.js
index 420be798293..3675ed6a410 100644
--- a/tests/baselines/reference/subtypingWithObjectMembers.js
+++ b/tests/baselines/reference/subtypingWithObjectMembers.js
@@ -81,16 +81,14 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Derived));
@@ -104,8 +102,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
@@ -117,8 +114,7 @@ var A2 = (function () {
 var B2 = (function (_super) {
     __extends(B2, _super);
     function B2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B2;
 }(A2));
@@ -130,8 +126,7 @@ var A3 = (function () {
 var B3 = (function (_super) {
     __extends(B3, _super);
     function B3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B3;
 }(A3));
@@ -145,8 +140,7 @@ var TwoLevels;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(A));
@@ -158,8 +152,7 @@ var TwoLevels;
     var B2 = (function (_super) {
         __extends(B2, _super);
         function B2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B2;
     }(A2));
@@ -171,8 +164,7 @@ var TwoLevels;
     var B3 = (function (_super) {
         __extends(B3, _super);
         function B3() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B3;
     }(A3));
diff --git a/tests/baselines/reference/subtypingWithObjectMembers4.js b/tests/baselines/reference/subtypingWithObjectMembers4.js
index 0bb50afe985..404b6cbe988 100644
--- a/tests/baselines/reference/subtypingWithObjectMembers4.js
+++ b/tests/baselines/reference/subtypingWithObjectMembers4.js
@@ -48,8 +48,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
@@ -61,8 +60,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
@@ -74,8 +72,7 @@ var A2 = (function () {
 var B2 = (function (_super) {
     __extends(B2, _super);
     function B2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B2;
 }(A2));
@@ -87,8 +84,7 @@ var A3 = (function () {
 var B3 = (function (_super) {
     __extends(B3, _super);
     function B3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B3;
 }(A3));
diff --git a/tests/baselines/reference/subtypingWithObjectMembersAccessibility.js b/tests/baselines/reference/subtypingWithObjectMembersAccessibility.js
index ec3b8382eca..8b168ea73b5 100644
--- a/tests/baselines/reference/subtypingWithObjectMembersAccessibility.js
+++ b/tests/baselines/reference/subtypingWithObjectMembersAccessibility.js
@@ -48,8 +48,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
@@ -61,8 +60,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
@@ -74,8 +72,7 @@ var A2 = (function () {
 var B2 = (function (_super) {
     __extends(B2, _super);
     function B2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B2;
 }(A2));
@@ -87,8 +84,7 @@ var A3 = (function () {
 var B3 = (function (_super) {
     __extends(B3, _super);
     function B3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B3;
 }(A3));
diff --git a/tests/baselines/reference/subtypingWithObjectMembersAccessibility2.js b/tests/baselines/reference/subtypingWithObjectMembersAccessibility2.js
index 24f36819ff6..0a83b760218 100644
--- a/tests/baselines/reference/subtypingWithObjectMembersAccessibility2.js
+++ b/tests/baselines/reference/subtypingWithObjectMembersAccessibility2.js
@@ -76,8 +76,7 @@ var Base = (function () {
 var Derived = (function (_super) {
     __extends(Derived, _super);
     function Derived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived;
 }(Base));
@@ -91,8 +90,7 @@ var ExplicitPublic;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(A));
@@ -104,8 +102,7 @@ var ExplicitPublic;
     var B2 = (function (_super) {
         __extends(B2, _super);
         function B2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B2;
     }(A2));
@@ -117,8 +114,7 @@ var ExplicitPublic;
     var B3 = (function (_super) {
         __extends(B3, _super);
         function B3() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B3;
     }(A3));
@@ -133,8 +129,7 @@ var ImplicitPublic;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(A));
@@ -146,8 +141,7 @@ var ImplicitPublic;
     var B2 = (function (_super) {
         __extends(B2, _super);
         function B2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B2;
     }(A2));
@@ -159,8 +153,7 @@ var ImplicitPublic;
     var B3 = (function (_super) {
         __extends(B3, _super);
         function B3() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B3;
     }(A3));
diff --git a/tests/baselines/reference/subtypingWithStringIndexer.js b/tests/baselines/reference/subtypingWithStringIndexer.js
index 95a71a018d1..195b7d2192e 100644
--- a/tests/baselines/reference/subtypingWithStringIndexer.js
+++ b/tests/baselines/reference/subtypingWithStringIndexer.js
@@ -55,16 +55,14 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
 var B2 = (function (_super) {
     __extends(B2, _super);
     function B2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B2;
 }(A));
@@ -78,32 +76,28 @@ var Generics;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(A));
     var B2 = (function (_super) {
         __extends(B2, _super);
         function B2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B2;
     }(A));
     var B3 = (function (_super) {
         __extends(B3, _super);
         function B3() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B3;
     }(A));
     var B4 = (function (_super) {
         __extends(B4, _super);
         function B4() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B4;
     }(A));
diff --git a/tests/baselines/reference/subtypingWithStringIndexer3.js b/tests/baselines/reference/subtypingWithStringIndexer3.js
index fd9b400cb3d..0b2a57324eb 100644
--- a/tests/baselines/reference/subtypingWithStringIndexer3.js
+++ b/tests/baselines/reference/subtypingWithStringIndexer3.js
@@ -58,16 +58,14 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
 var B2 = (function (_super) {
     __extends(B2, _super);
     function B2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B2;
 }(A));
@@ -81,40 +79,35 @@ var Generics;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(A));
     var B2 = (function (_super) {
         __extends(B2, _super);
         function B2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B2;
     }(A));
     var B3 = (function (_super) {
         __extends(B3, _super);
         function B3() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B3;
     }(A));
     var B4 = (function (_super) {
         __extends(B4, _super);
         function B4() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B4;
     }(A));
     var B5 = (function (_super) {
         __extends(B5, _super);
         function B5() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B5;
     }(A));
diff --git a/tests/baselines/reference/subtypingWithStringIndexer4.js b/tests/baselines/reference/subtypingWithStringIndexer4.js
index 46178d1dc32..2937261ad05 100644
--- a/tests/baselines/reference/subtypingWithStringIndexer4.js
+++ b/tests/baselines/reference/subtypingWithStringIndexer4.js
@@ -42,8 +42,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return B;
 }(A));
@@ -57,16 +56,14 @@ var Generics;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(A));
     var B3 = (function (_super) {
         __extends(B3, _super);
         function B3() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B3;
     }(A));
diff --git a/tests/baselines/reference/super.js b/tests/baselines/reference/super.js
index 54afddcc119..504e8542d4d 100644
--- a/tests/baselines/reference/super.js
+++ b/tests/baselines/reference/super.js
@@ -58,8 +58,7 @@ var Base = (function () {
 var Sub1 = (function (_super) {
     __extends(Sub1, _super);
     function Sub1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Sub1.prototype.foo = function () {
         return "sub1" + _super.prototype.foo.call(this) + _super.prototype.bar.call(this);
@@ -69,8 +68,7 @@ var Sub1 = (function (_super) {
 var SubSub1 = (function (_super) {
     __extends(SubSub1, _super);
     function SubSub1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     SubSub1.prototype.foo = function () {
         return "subsub1" + _super.prototype.foo.call(this);
diff --git a/tests/baselines/reference/super1.js b/tests/baselines/reference/super1.js
index 8ef621cdf2b..9f1289dce55 100644
--- a/tests/baselines/reference/super1.js
+++ b/tests/baselines/reference/super1.js
@@ -84,8 +84,7 @@ var Base1 = (function () {
 var Sub1 = (function (_super) {
     __extends(Sub1, _super);
     function Sub1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Sub1.prototype.bar = function () {
         return "base";
@@ -95,8 +94,7 @@ var Sub1 = (function (_super) {
 var SubSub1 = (function (_super) {
     __extends(SubSub1, _super);
     function SubSub1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     SubSub1.prototype.bar = function () {
         return _super.prototype.super.foo;
@@ -115,8 +113,7 @@ var Base2 = (function () {
 var SubE2 = (function (_super) {
     __extends(SubE2, _super);
     function SubE2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     SubE2.prototype.bar = function () {
         return _super.prototype.prototype.foo = null;
@@ -135,8 +132,7 @@ var Base3 = (function () {
 var SubE3 = (function (_super) {
     __extends(SubE3, _super);
     function SubE3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     SubE3.prototype.bar = function () {
         return _super.prototype.bar.call(this);
@@ -157,8 +153,7 @@ var Base4;
     var SubSub4 = (function (_super) {
         __extends(SubSub4, _super);
         function SubSub4() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         SubSub4.prototype.x = function () {
             return _super.prototype.x.call(this);
diff --git a/tests/baselines/reference/super2.js b/tests/baselines/reference/super2.js
index 80e26c36f7c..1d2331052db 100644
--- a/tests/baselines/reference/super2.js
+++ b/tests/baselines/reference/super2.js
@@ -71,8 +71,7 @@ var Base5 = (function () {
 var Sub5 = (function (_super) {
     __extends(Sub5, _super);
     function Sub5() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Sub5.prototype.x = function () {
         return "SubX";
@@ -82,8 +81,7 @@ var Sub5 = (function (_super) {
 var SubSub5 = (function (_super) {
     __extends(SubSub5, _super);
     function SubSub5() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     SubSub5.prototype.x = function () {
         return _super.prototype.x.call(this);
@@ -105,8 +103,7 @@ var Base6 = (function () {
 var Sub6 = (function (_super) {
     __extends(Sub6, _super);
     function Sub6() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Sub6.prototype.y = function () {
         return "SubY";
@@ -116,8 +113,7 @@ var Sub6 = (function (_super) {
 var SubSub6 = (function (_super) {
     __extends(SubSub6, _super);
     function SubSub6() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     SubSub6.prototype.y = function () {
         return _super.prototype.y.call(this);
diff --git a/tests/baselines/reference/superAccess.js b/tests/baselines/reference/superAccess.js
index 8c9d93f3a36..0bd9d305d2e 100644
--- a/tests/baselines/reference/superAccess.js
+++ b/tests/baselines/reference/superAccess.js
@@ -30,8 +30,7 @@ MyBase.S1 = 5;
 var MyDerived = (function (_super) {
     __extends(MyDerived, _super);
     function MyDerived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     MyDerived.prototype.foo = function () {
         var l3 = _super.prototype.S1; // Expected => Error: Only public instance methods of the base class are accessible via the 'super' keyword
diff --git a/tests/baselines/reference/superAccessInFatArrow1.js b/tests/baselines/reference/superAccessInFatArrow1.js
index be97707b12a..a7f964309f7 100644
--- a/tests/baselines/reference/superAccessInFatArrow1.js
+++ b/tests/baselines/reference/superAccessInFatArrow1.js
@@ -34,8 +34,7 @@ var test;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         B.prototype.bar = function (callback) {
         };
diff --git a/tests/baselines/reference/superCallInStaticMethod.js b/tests/baselines/reference/superCallInStaticMethod.js
index 6cf9f79e7a4..b31110fdf78 100644
--- a/tests/baselines/reference/superCallInStaticMethod.js
+++ b/tests/baselines/reference/superCallInStaticMethod.js
@@ -62,8 +62,7 @@ var Doing = (function () {
 var Other = (function (_super) {
     __extends(Other, _super);
     function Other() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     // in static method
     Other.staticMethod = function () {
diff --git a/tests/baselines/reference/superCallWithMissingBaseClass.js b/tests/baselines/reference/superCallWithMissingBaseClass.js
index 561b7300fe4..16f11088640 100644
--- a/tests/baselines/reference/superCallWithMissingBaseClass.js
+++ b/tests/baselines/reference/superCallWithMissingBaseClass.js
@@ -18,8 +18,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var Foo = (function (_super) {
     __extends(Foo, _super);
     function Foo() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Foo.prototype.m1 = function () {
         return _super.prototype.m1.call(this);
diff --git a/tests/baselines/reference/superInCatchBlock1.js b/tests/baselines/reference/superInCatchBlock1.js
index 9eb7df62c1a..e1fc0f97024 100644
--- a/tests/baselines/reference/superInCatchBlock1.js
+++ b/tests/baselines/reference/superInCatchBlock1.js
@@ -28,8 +28,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     B.prototype.m = function () {
         try {
diff --git a/tests/baselines/reference/superInObjectLiterals_ES5.js b/tests/baselines/reference/superInObjectLiterals_ES5.js
index adeda5835cb..816277e4e9e 100644
--- a/tests/baselines/reference/superInObjectLiterals_ES5.js
+++ b/tests/baselines/reference/superInObjectLiterals_ES5.js
@@ -100,8 +100,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     B.prototype.f = function () {
         var _this = this;
diff --git a/tests/baselines/reference/superPropertyAccess.js b/tests/baselines/reference/superPropertyAccess.js
index b1377eb9cde..7b5823e598b 100644
--- a/tests/baselines/reference/superPropertyAccess.js
+++ b/tests/baselines/reference/superPropertyAccess.js
@@ -61,8 +61,7 @@ var MyBase = (function () {
 var MyDerived = (function (_super) {
     __extends(MyDerived, _super);
     function MyDerived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     MyDerived.prototype.foo = function () {
         _super.prototype.m1.call(this, "hi"); // Should be allowed, method on base prototype
diff --git a/tests/baselines/reference/superPropertyAccessInComputedPropertiesOfNestedType_ES5.js b/tests/baselines/reference/superPropertyAccessInComputedPropertiesOfNestedType_ES5.js
index 1397a0748ae..956bce4ef2e 100644
--- a/tests/baselines/reference/superPropertyAccessInComputedPropertiesOfNestedType_ES5.js
+++ b/tests/baselines/reference/superPropertyAccessInComputedPropertiesOfNestedType_ES5.js
@@ -29,8 +29,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     B.prototype.foo = function () { return 2; };
     B.prototype.bar = function () {
diff --git a/tests/baselines/reference/superPropertyAccess_ES5.js b/tests/baselines/reference/superPropertyAccess_ES5.js
index 4e817b7bbf1..45c32076be9 100644
--- a/tests/baselines/reference/superPropertyAccess_ES5.js
+++ b/tests/baselines/reference/superPropertyAccess_ES5.js
@@ -72,8 +72,7 @@ var A = (function () {
 var B = (function (_super) {
     __extends(B, _super);
     function B() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Object.defineProperty(B.prototype, "property", {
         set: function (value) {
diff --git a/tests/baselines/reference/superSymbolIndexedAccess5.js b/tests/baselines/reference/superSymbolIndexedAccess5.js
index 0796c912d8c..dd37deb5af3 100644
--- a/tests/baselines/reference/superSymbolIndexedAccess5.js
+++ b/tests/baselines/reference/superSymbolIndexedAccess5.js
@@ -31,8 +31,7 @@ var Foo = (function () {
 var Bar = (function (_super) {
     __extends(Bar, _super);
     function Bar() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Bar.prototype[symbol] = function () {
         return _super.prototype[symbol].call(this);
diff --git a/tests/baselines/reference/superSymbolIndexedAccess6.js b/tests/baselines/reference/superSymbolIndexedAccess6.js
index ee376cec2cb..8c8534b428a 100644
--- a/tests/baselines/reference/superSymbolIndexedAccess6.js
+++ b/tests/baselines/reference/superSymbolIndexedAccess6.js
@@ -31,8 +31,7 @@ var Foo = (function () {
 var Bar = (function (_super) {
     __extends(Bar, _super);
     function Bar() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Bar[symbol] = function () {
         return _super[symbol].call(this);
diff --git a/tests/baselines/reference/super_inside-object-literal-getters-and-setters.js b/tests/baselines/reference/super_inside-object-literal-getters-and-setters.js
index ed71cebe3c7..6815b71ce11 100644
--- a/tests/baselines/reference/super_inside-object-literal-getters-and-setters.js
+++ b/tests/baselines/reference/super_inside-object-literal-getters-and-setters.js
@@ -57,8 +57,7 @@ var F = (function () {
 var SuperObjectTest = (function (_super) {
     __extends(SuperObjectTest, _super);
     function SuperObjectTest() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     SuperObjectTest.prototype.testing = function () {
         var test = {
diff --git a/tests/baselines/reference/switchStatements.js b/tests/baselines/reference/switchStatements.js
index 7aac6cb47e0..2e1aecc7288 100644
--- a/tests/baselines/reference/switchStatements.js
+++ b/tests/baselines/reference/switchStatements.js
@@ -98,8 +98,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(C));
diff --git a/tests/baselines/reference/systemModuleWithSuperClass.js b/tests/baselines/reference/systemModuleWithSuperClass.js
index 59aff947e5c..78c09355fa0 100644
--- a/tests/baselines/reference/systemModuleWithSuperClass.js
+++ b/tests/baselines/reference/systemModuleWithSuperClass.js
@@ -49,8 +49,7 @@ System.register(["./foo"], function (exports_1, context_1) {
             Bar = (function (_super) {
                 __extends(Bar, _super);
                 function Bar() {
-                    var _this = _super.apply(this, arguments) || this;
-                    return _this;
+                    return _super.apply(this, arguments) || this;
                 }
                 return Bar;
             }(foo_1.Foo));
diff --git a/tests/baselines/reference/thisInInvalidContexts.js b/tests/baselines/reference/thisInInvalidContexts.js
index 7fcfaf9d317..1fc1c734639 100644
--- a/tests/baselines/reference/thisInInvalidContexts.js
+++ b/tests/baselines/reference/thisInInvalidContexts.js
@@ -97,8 +97,7 @@ genericFunc(undefined); // Should be an error
 var ErrClass3 = (function (_super) {
     __extends(ErrClass3, _super);
     function ErrClass3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return ErrClass3;
 }(this));
diff --git a/tests/baselines/reference/thisInInvalidContextsExternalModule.js b/tests/baselines/reference/thisInInvalidContextsExternalModule.js
index 546863b5216..f8cb6d695dc 100644
--- a/tests/baselines/reference/thisInInvalidContextsExternalModule.js
+++ b/tests/baselines/reference/thisInInvalidContextsExternalModule.js
@@ -98,8 +98,7 @@ genericFunc(undefined); // Should be an error
 var ErrClass3 = (function (_super) {
     __extends(ErrClass3, _super);
     function ErrClass3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return ErrClass3;
 }(this));
diff --git a/tests/baselines/reference/thisTypeInFunctions.js b/tests/baselines/reference/thisTypeInFunctions.js
index 6eaaed5c497..6400f410a09 100644
--- a/tests/baselines/reference/thisTypeInFunctions.js
+++ b/tests/baselines/reference/thisTypeInFunctions.js
@@ -227,8 +227,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D;
 }(C));
@@ -337,8 +336,7 @@ var Base1 = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived1;
 }(Base1));
@@ -352,8 +350,7 @@ var Base2 = (function () {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Base2));
diff --git a/tests/baselines/reference/thisTypeInFunctionsNegative.js b/tests/baselines/reference/thisTypeInFunctionsNegative.js
index 08e12f49dca..446bc15e6d9 100644
--- a/tests/baselines/reference/thisTypeInFunctionsNegative.js
+++ b/tests/baselines/reference/thisTypeInFunctionsNegative.js
@@ -296,8 +296,7 @@ var Base1 = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived1;
 }(Base1));
@@ -311,8 +310,7 @@ var Base2 = (function () {
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Base2));
diff --git a/tests/baselines/reference/tsxExternalModuleEmit1.js b/tests/baselines/reference/tsxExternalModuleEmit1.js
index 0f6b8716ed0..58e7f1c8d85 100644
--- a/tests/baselines/reference/tsxExternalModuleEmit1.js
+++ b/tests/baselines/reference/tsxExternalModuleEmit1.js
@@ -42,8 +42,7 @@ var React = require("react");
 var Button = (function (_super) {
     __extends(Button, _super);
     function Button() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     Button.prototype.render = function () {
         return <button>Some button</button>;
@@ -64,8 +63,7 @@ var button_1 = require("./button");
 var App = (function (_super) {
     __extends(App, _super);
     function App() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     App.prototype.render = function () {
         return <button_1.Button />;
diff --git a/tests/baselines/reference/tsxStatelessFunctionComponents2.js b/tests/baselines/reference/tsxStatelessFunctionComponents2.js
index f7ac96cff1f..88d91723501 100644
--- a/tests/baselines/reference/tsxStatelessFunctionComponents2.js
+++ b/tests/baselines/reference/tsxStatelessFunctionComponents2.js
@@ -52,8 +52,7 @@ function Greet(x) {
 var BigGreeter = (function (_super) {
     __extends(BigGreeter, _super);
     function BigGreeter() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     BigGreeter.prototype.render = function () {
         return <div></div>;
diff --git a/tests/baselines/reference/tsxUnionTypeComponent1.js b/tests/baselines/reference/tsxUnionTypeComponent1.js
index 56a6896f052..3520b5af372 100644
--- a/tests/baselines/reference/tsxUnionTypeComponent1.js
+++ b/tests/baselines/reference/tsxUnionTypeComponent1.js
@@ -35,8 +35,7 @@ var React = require("react");
 var MyComponent = (function (_super) {
     __extends(MyComponent, _super);
     function MyComponent() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     MyComponent.prototype.render = function () {
         var AnyComponent = this.props.AnyComponent;
@@ -50,8 +49,7 @@ React.createElement(MyComponent, { AnyComponent: function () { return React.crea
 var MyButtonComponent = (function (_super) {
     __extends(MyButtonComponent, _super);
     function MyButtonComponent() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return MyButtonComponent;
 }(React.Component));
diff --git a/tests/baselines/reference/typeAssertions.js b/tests/baselines/reference/typeAssertions.js
index 083cb5e94b3..a57fb222a77 100644
--- a/tests/baselines/reference/typeAssertions.js
+++ b/tests/baselines/reference/typeAssertions.js
@@ -74,8 +74,7 @@ var SomeBase = (function () {
 var SomeDerived = (function (_super) {
     __extends(SomeDerived, _super);
     function SomeDerived() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return SomeDerived;
 }(SomeBase));
diff --git a/tests/baselines/reference/typeGuardFunction.js b/tests/baselines/reference/typeGuardFunction.js
index 45bf0853b13..b88d1038969 100644
--- a/tests/baselines/reference/typeGuardFunction.js
+++ b/tests/baselines/reference/typeGuardFunction.js
@@ -102,8 +102,7 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/typeGuardFunctionErrors.js b/tests/baselines/reference/typeGuardFunctionErrors.js
index 727640ee8af..6f0880ad7f5 100644
--- a/tests/baselines/reference/typeGuardFunctionErrors.js
+++ b/tests/baselines/reference/typeGuardFunctionErrors.js
@@ -164,8 +164,7 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/typeGuardFunctionGenerics.js b/tests/baselines/reference/typeGuardFunctionGenerics.js
index dad77edf232..703c809274f 100644
--- a/tests/baselines/reference/typeGuardFunctionGenerics.js
+++ b/tests/baselines/reference/typeGuardFunctionGenerics.js
@@ -52,8 +52,7 @@ var B = (function () {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(A));
diff --git a/tests/baselines/reference/typeGuardFunctionOfFormThis.js b/tests/baselines/reference/typeGuardFunctionOfFormThis.js
index eec648976c6..c052ea7d72b 100644
--- a/tests/baselines/reference/typeGuardFunctionOfFormThis.js
+++ b/tests/baselines/reference/typeGuardFunctionOfFormThis.js
@@ -161,8 +161,7 @@ var RoyalGuard = (function () {
 var LeadGuard = (function (_super) {
     __extends(LeadGuard, _super);
     function LeadGuard() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     LeadGuard.prototype.lead = function () { };
     ;
@@ -171,8 +170,7 @@ var LeadGuard = (function (_super) {
 var FollowerGuard = (function (_super) {
     __extends(FollowerGuard, _super);
     function FollowerGuard() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     FollowerGuard.prototype.follow = function () { };
     ;
@@ -226,8 +224,7 @@ var ArrowGuard = (function () {
 var ArrowElite = (function (_super) {
     __extends(ArrowElite, _super);
     function ArrowElite() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     ArrowElite.prototype.defend = function () { };
     return ArrowElite;
@@ -235,8 +232,7 @@ var ArrowElite = (function (_super) {
 var ArrowMedic = (function (_super) {
     __extends(ArrowMedic, _super);
     function ArrowMedic() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     ArrowMedic.prototype.heal = function () { };
     return ArrowMedic;
@@ -270,8 +266,7 @@ var MimicGuard = (function () {
 var MimicLeader = (function (_super) {
     __extends(MimicLeader, _super);
     function MimicLeader() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     MimicLeader.prototype.lead = function () { };
     return MimicLeader;
@@ -279,8 +274,7 @@ var MimicLeader = (function (_super) {
 var MimicFollower = (function (_super) {
     __extends(MimicFollower, _super);
     function MimicFollower() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     MimicFollower.prototype.follow = function () { };
     return MimicFollower;
diff --git a/tests/baselines/reference/typeGuardFunctionOfFormThisErrors.js b/tests/baselines/reference/typeGuardFunctionOfFormThisErrors.js
index a82d3d2527f..a85a207a665 100644
--- a/tests/baselines/reference/typeGuardFunctionOfFormThisErrors.js
+++ b/tests/baselines/reference/typeGuardFunctionOfFormThisErrors.js
@@ -79,8 +79,7 @@ var RoyalGuard = (function () {
 var LeadGuard = (function (_super) {
     __extends(LeadGuard, _super);
     function LeadGuard() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     LeadGuard.prototype.lead = function () { };
     ;
@@ -89,8 +88,7 @@ var LeadGuard = (function (_super) {
 var FollowerGuard = (function (_super) {
     __extends(FollowerGuard, _super);
     function FollowerGuard() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     FollowerGuard.prototype.follow = function () { };
     ;
diff --git a/tests/baselines/reference/typeGuardOfFormInstanceOf.js b/tests/baselines/reference/typeGuardOfFormInstanceOf.js
index a94d5fe93e7..a181a446a81 100644
--- a/tests/baselines/reference/typeGuardOfFormInstanceOf.js
+++ b/tests/baselines/reference/typeGuardOfFormInstanceOf.js
@@ -91,8 +91,7 @@ var C2 = (function () {
 var D1 = (function (_super) {
     __extends(D1, _super);
     function D1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D1;
 }(C1));
diff --git a/tests/baselines/reference/typeGuardOfFormIsType.js b/tests/baselines/reference/typeGuardOfFormIsType.js
index 2d83a62ad3e..14e9259a9e7 100644
--- a/tests/baselines/reference/typeGuardOfFormIsType.js
+++ b/tests/baselines/reference/typeGuardOfFormIsType.js
@@ -56,8 +56,7 @@ var C2 = (function () {
 var D1 = (function (_super) {
     __extends(D1, _super);
     function D1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D1;
 }(C1));
diff --git a/tests/baselines/reference/typeGuardOfFormThisMember.js b/tests/baselines/reference/typeGuardOfFormThisMember.js
index 541c03dd4b4..52097af34f7 100644
--- a/tests/baselines/reference/typeGuardOfFormThisMember.js
+++ b/tests/baselines/reference/typeGuardOfFormThisMember.js
@@ -128,8 +128,7 @@ var Test;
     var Directory = (function (_super) {
         __extends(Directory, _super);
         function Directory() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Directory;
     }(FileSystemObject));
diff --git a/tests/baselines/reference/typeGuardOfFormThisMemberErrors.js b/tests/baselines/reference/typeGuardOfFormThisMemberErrors.js
index b61676b40c3..c65445a3a5a 100644
--- a/tests/baselines/reference/typeGuardOfFormThisMemberErrors.js
+++ b/tests/baselines/reference/typeGuardOfFormThisMemberErrors.js
@@ -78,8 +78,7 @@ var Test;
     var Directory = (function (_super) {
         __extends(Directory, _super);
         function Directory() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return Directory;
     }(FileSystemObject));
diff --git a/tests/baselines/reference/typeMatch2.js b/tests/baselines/reference/typeMatch2.js
index 03408c6196b..2cae93924bc 100644
--- a/tests/baselines/reference/typeMatch2.js
+++ b/tests/baselines/reference/typeMatch2.js
@@ -65,8 +65,7 @@ var Animal = (function () {
 var Giraffe = (function (_super) {
     __extends(Giraffe, _super);
     function Giraffe() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Giraffe;
 }(Animal));
diff --git a/tests/baselines/reference/typeParameterAsBaseClass.js b/tests/baselines/reference/typeParameterAsBaseClass.js
index d67259304c3..15d1c3b396e 100644
--- a/tests/baselines/reference/typeParameterAsBaseClass.js
+++ b/tests/baselines/reference/typeParameterAsBaseClass.js
@@ -11,8 +11,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(T));
diff --git a/tests/baselines/reference/typeParameterAsBaseType.js b/tests/baselines/reference/typeParameterAsBaseType.js
index 24f8789a82d..2d0962f01d7 100644
--- a/tests/baselines/reference/typeParameterAsBaseType.js
+++ b/tests/baselines/reference/typeParameterAsBaseType.js
@@ -21,16 +21,14 @@ var __extends = (this && this.__extends) || function (d, b) {
 var C = (function (_super) {
     __extends(C, _super);
     function C() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C;
 }(T));
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }(U));
diff --git a/tests/baselines/reference/typeParameterExtendingUnion1.js b/tests/baselines/reference/typeParameterExtendingUnion1.js
index 55bc51bbdbb..2738aa20528 100644
--- a/tests/baselines/reference/typeParameterExtendingUnion1.js
+++ b/tests/baselines/reference/typeParameterExtendingUnion1.js
@@ -27,16 +27,14 @@ var Animal = (function () {
 var Cat = (function (_super) {
     __extends(Cat, _super);
     function Cat() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Cat;
 }(Animal));
 var Dog = (function (_super) {
     __extends(Dog, _super);
     function Dog() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Dog;
 }(Animal));
diff --git a/tests/baselines/reference/typeParameterExtendingUnion2.js b/tests/baselines/reference/typeParameterExtendingUnion2.js
index 75f62e94c67..b3754436f26 100644
--- a/tests/baselines/reference/typeParameterExtendingUnion2.js
+++ b/tests/baselines/reference/typeParameterExtendingUnion2.js
@@ -27,16 +27,14 @@ var Animal = (function () {
 var Cat = (function (_super) {
     __extends(Cat, _super);
     function Cat() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Cat;
 }(Animal));
 var Dog = (function (_super) {
     __extends(Dog, _super);
     function Dog() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Dog;
 }(Animal));
diff --git a/tests/baselines/reference/typeValueConflict1.js b/tests/baselines/reference/typeValueConflict1.js
index a1ecef212da..8711a656bf5 100644
--- a/tests/baselines/reference/typeValueConflict1.js
+++ b/tests/baselines/reference/typeValueConflict1.js
@@ -33,8 +33,7 @@ var M2;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(M1.A));
diff --git a/tests/baselines/reference/typeValueConflict2.js b/tests/baselines/reference/typeValueConflict2.js
index a0cfeda07ec..7abda8110b6 100644
--- a/tests/baselines/reference/typeValueConflict2.js
+++ b/tests/baselines/reference/typeValueConflict2.js
@@ -40,8 +40,7 @@ var M2;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(M1.A));
@@ -52,8 +51,7 @@ var M3;
     var B = (function (_super) {
         __extends(B, _super);
         function B() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return B;
     }(M1.A));
diff --git a/tests/baselines/reference/typeofClass2.js b/tests/baselines/reference/typeofClass2.js
index b3da31103df..f1ec6a77b14 100644
--- a/tests/baselines/reference/typeofClass2.js
+++ b/tests/baselines/reference/typeofClass2.js
@@ -37,8 +37,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     D.baz = function (x) { };
     D.prototype.foo = function () { };
diff --git a/tests/baselines/reference/typesWithSpecializedCallSignatures.js b/tests/baselines/reference/typesWithSpecializedCallSignatures.js
index 853cb5eafd7..045f7b40e55 100644
--- a/tests/baselines/reference/typesWithSpecializedCallSignatures.js
+++ b/tests/baselines/reference/typesWithSpecializedCallSignatures.js
@@ -56,16 +56,14 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived1;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/typesWithSpecializedConstructSignatures.js b/tests/baselines/reference/typesWithSpecializedConstructSignatures.js
index 99314597440..b4d42d819ed 100644
--- a/tests/baselines/reference/typesWithSpecializedConstructSignatures.js
+++ b/tests/baselines/reference/typesWithSpecializedConstructSignatures.js
@@ -54,16 +54,14 @@ var Base = (function () {
 var Derived1 = (function (_super) {
     __extends(Derived1, _super);
     function Derived1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived1;
 }(Base));
 var Derived2 = (function (_super) {
     __extends(Derived2, _super);
     function Derived2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return Derived2;
 }(Base));
diff --git a/tests/baselines/reference/undeclaredBase.js b/tests/baselines/reference/undeclaredBase.js
index 64117b1935a..4b7813231cf 100644
--- a/tests/baselines/reference/undeclaredBase.js
+++ b/tests/baselines/reference/undeclaredBase.js
@@ -14,8 +14,7 @@ var M;
     var C = (function (_super) {
         __extends(C, _super);
         function C() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return C;
     }(M.I));
diff --git a/tests/baselines/reference/undefinedIsSubtypeOfEverything.js b/tests/baselines/reference/undefinedIsSubtypeOfEverything.js
index 451aec91aff..86948a2d9e6 100644
--- a/tests/baselines/reference/undefinedIsSubtypeOfEverything.js
+++ b/tests/baselines/reference/undefinedIsSubtypeOfEverything.js
@@ -136,120 +136,105 @@ var Base = (function () {
 var D0 = (function (_super) {
     __extends(D0, _super);
     function D0() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D0;
 }(Base));
 var DA = (function (_super) {
     __extends(DA, _super);
     function DA() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return DA;
 }(Base));
 var D1 = (function (_super) {
     __extends(D1, _super);
     function D1() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D1;
 }(Base));
 var D1A = (function (_super) {
     __extends(D1A, _super);
     function D1A() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D1A;
 }(Base));
 var D2 = (function (_super) {
     __extends(D2, _super);
     function D2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D2;
 }(Base));
 var D2A = (function (_super) {
     __extends(D2A, _super);
     function D2A() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D2A;
 }(Base));
 var D3 = (function (_super) {
     __extends(D3, _super);
     function D3() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D3;
 }(Base));
 var D3A = (function (_super) {
     __extends(D3A, _super);
     function D3A() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D3A;
 }(Base));
 var D4 = (function (_super) {
     __extends(D4, _super);
     function D4() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D4;
 }(Base));
 var D5 = (function (_super) {
     __extends(D5, _super);
     function D5() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D5;
 }(Base));
 var D6 = (function (_super) {
     __extends(D6, _super);
     function D6() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D6;
 }(Base));
 var D7 = (function (_super) {
     __extends(D7, _super);
     function D7() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D7;
 }(Base));
 var D8 = (function (_super) {
     __extends(D8, _super);
     function D8() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D8;
 }(Base));
 var D9 = (function (_super) {
     __extends(D9, _super);
     function D9() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D9;
 }(Base));
 var D10 = (function (_super) {
     __extends(D10, _super);
     function D10() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D10;
 }(Base));
@@ -260,8 +245,7 @@ var E;
 var D11 = (function (_super) {
     __extends(D11, _super);
     function D11() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D11;
 }(Base));
@@ -273,8 +257,7 @@ var f;
 var D12 = (function (_super) {
     __extends(D12, _super);
     function D12() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D12;
 }(Base));
@@ -290,24 +273,21 @@ var c;
 var D13 = (function (_super) {
     __extends(D13, _super);
     function D13() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D13;
 }(Base));
 var D14 = (function (_super) {
     __extends(D14, _super);
     function D14() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D14;
 }(Base));
 var D15 = (function (_super) {
     __extends(D15, _super);
     function D15() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D15;
 }(Base));
@@ -317,16 +297,14 @@ var D15 = (function (_super) {
 var D16 = (function (_super) {
     __extends(D16, _super);
     function D16() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D16;
 }(Base));
 var D17 = (function (_super) {
     __extends(D17, _super);
     function D17() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return D17;
 }(Base));
diff --git a/tests/baselines/reference/underscoreMapFirst.js b/tests/baselines/reference/underscoreMapFirst.js
index 61f1bf2c9f9..c8e936af527 100644
--- a/tests/baselines/reference/underscoreMapFirst.js
+++ b/tests/baselines/reference/underscoreMapFirst.js
@@ -57,8 +57,7 @@ var __extends = (this && this.__extends) || function (d, b) {
 var MyView = (function (_super) {
     __extends(MyView, _super);
     function MyView() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     MyView.prototype.getDataSeries = function () {
         var data = this.model.get("data");
diff --git a/tests/baselines/reference/unionTypeEquivalence.js b/tests/baselines/reference/unionTypeEquivalence.js
index b0be82122de..e4d0acc893c 100644
--- a/tests/baselines/reference/unionTypeEquivalence.js
+++ b/tests/baselines/reference/unionTypeEquivalence.js
@@ -34,8 +34,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     D.prototype.foo = function () { };
     return D;
diff --git a/tests/baselines/reference/unionTypeFromArrayLiteral.js b/tests/baselines/reference/unionTypeFromArrayLiteral.js
index 72cf61f72fd..83ad2a34394 100644
--- a/tests/baselines/reference/unionTypeFromArrayLiteral.js
+++ b/tests/baselines/reference/unionTypeFromArrayLiteral.js
@@ -54,8 +54,7 @@ var D = (function () {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     E.prototype.foo3 = function () { };
     return E;
@@ -63,8 +62,7 @@ var E = (function (_super) {
 var F = (function (_super) {
     __extends(F, _super);
     function F() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     F.prototype.foo4 = function () { };
     return F;
diff --git a/tests/baselines/reference/unionTypesAssignability.js b/tests/baselines/reference/unionTypesAssignability.js
index fafc4ec85fa..231b8b27f3b 100644
--- a/tests/baselines/reference/unionTypesAssignability.js
+++ b/tests/baselines/reference/unionTypesAssignability.js
@@ -88,8 +88,7 @@ var C = (function () {
 var D = (function (_super) {
     __extends(D, _super);
     function D() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     D.prototype.foo1 = function () { };
     return D;
@@ -97,8 +96,7 @@ var D = (function (_super) {
 var E = (function (_super) {
     __extends(E, _super);
     function E() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     E.prototype.foo2 = function () { };
     return E;
diff --git a/tests/baselines/reference/unspecializedConstraints.js b/tests/baselines/reference/unspecializedConstraints.js
index 7d5a4b9deed..1343bea602e 100644
--- a/tests/baselines/reference/unspecializedConstraints.js
+++ b/tests/baselines/reference/unspecializedConstraints.js
@@ -169,8 +169,7 @@ var ts;
     var Type = (function (_super) {
         __extends(Type, _super);
         function Type() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         Type.prototype.equals = function (that) {
             if (this === that)
diff --git a/tests/baselines/reference/untypedFunctionCallsWithTypeParameters1.js b/tests/baselines/reference/untypedFunctionCallsWithTypeParameters1.js
index 324dc784b67..b82a7cbc0ae 100644
--- a/tests/baselines/reference/untypedFunctionCallsWithTypeParameters1.js
+++ b/tests/baselines/reference/untypedFunctionCallsWithTypeParameters1.js
@@ -70,8 +70,7 @@ var r4 = c2(); // should be an error
 var C2 = (function (_super) {
     __extends(C2, _super);
     function C2() {
-        var _this = _super.apply(this, arguments) || this;
-        return _this;
+        return _super.apply(this, arguments) || this;
     }
     return C2;
 }(Function)); // error
diff --git a/tests/baselines/reference/unusedClassesinNamespace4.js b/tests/baselines/reference/unusedClassesinNamespace4.js
index 3c1dd16874e..0ab1227bf3d 100644
--- a/tests/baselines/reference/unusedClassesinNamespace4.js
+++ b/tests/baselines/reference/unusedClassesinNamespace4.js
@@ -36,8 +36,7 @@ var Validation;
     var c3 = (function (_super) {
         __extends(c3, _super);
         function c3() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return c3;
     }(c1));
diff --git a/tests/baselines/reference/unusedIdentifiersConsolidated1.js b/tests/baselines/reference/unusedIdentifiersConsolidated1.js
index fd7d859ac37..dbb261e5f2a 100644
--- a/tests/baselines/reference/unusedIdentifiersConsolidated1.js
+++ b/tests/baselines/reference/unusedIdentifiersConsolidated1.js
@@ -168,8 +168,7 @@ var Greeter;
     var class2 = (function (_super) {
         __extends(class2, _super);
         function class2() {
-            var _this = _super.apply(this, arguments) || this;
-            return _this;
+            return _super.apply(this, arguments) || this;
         }
         return class2;
     }(class1));

From e0c35f2c829079a00f73bcc9ff4abd671578c26e Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Tue, 27 Sep 2016 14:17:11 -0700
Subject: [PATCH 39/47] Restore arrow function.

---
 src/compiler/transformers/es6.ts | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/src/compiler/transformers/es6.ts b/src/compiler/transformers/es6.ts
index ed5659e8a3f..df21df5e1fb 100644
--- a/src/compiler/transformers/es6.ts
+++ b/src/compiler/transformers/es6.ts
@@ -224,7 +224,7 @@ namespace ts {
                 : visitorWorker(node);
         }
 
-        function saveStateAndInvoke<T>(node: Node, f: (node: Node) => T): T {
+        function saveStateAndInvoke<T extends Node, U>(node: T, f: (node: T) => U): U {
             const savedEnclosingFunction = enclosingFunction;
             const savedEnclosingNonArrowFunction = enclosingNonArrowFunction;
             const savedEnclosingNonAsyncFunctionBody = enclosingNonAsyncFunctionBody;
@@ -867,7 +867,7 @@ namespace ts {
             }
 
             if (constructor) {
-                const body = saveStateAndInvoke(constructor, makeTransformerForConstructorBodyAtOffset(statementOffset));
+                const body = saveStateAndInvoke(constructor, constructor => visitNodes(constructor.body.statements, visitor, isStatement, /*start*/ statementOffset));
                 addRange(statements, body);
             }
 
@@ -900,10 +900,6 @@ namespace ts {
             return block;
         }
 
-        function makeTransformerForConstructorBodyAtOffset(offset: number): (c: ConstructorDeclaration) => NodeArray<Statement> {
-            return constructor => visitNodes(constructor.body.statements, visitor, isStatement, /*start*/ offset);
-        }
-
         /**
          * We want to try to avoid emitting a return statement in certain cases if a user already returned something.
          * It would be pointless and generate dead code, so we'll try to make things a little bit prettier

From f8fbc22ef23e7c4bc5c2b75af30fb532d2208cb6 Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Tue, 27 Sep 2016 14:35:57 -0700
Subject: [PATCH 40/47] Reuse the 'captureThisForNode' function.

---
 src/compiler/transformers/es6.ts | 15 +--------------
 1 file changed, 1 insertion(+), 14 deletions(-)

diff --git a/src/compiler/transformers/es6.ts b/src/compiler/transformers/es6.ts
index df21df5e1fb..b0633c309ea 100644
--- a/src/compiler/transformers/es6.ts
+++ b/src/compiler/transformers/es6.ts
@@ -965,21 +965,8 @@ namespace ts {
 
                 // The constructor was generated for some reason.
                 // Create a captured '_this' variable.
-                statements.push(
-                    createVariableStatement(
-                        /*modifiers*/ undefined,
-                        createVariableDeclarationList([
-                            createVariableDeclaration(
-                                "_this",
-                                /*type*/ undefined,
-                                superReturnValueOrThis
-                            )
-                        ]),
-                    /*location*/ extendsClauseElement)
-                );
-
+                captureThisForNode(statements, constructor, superReturnValueOrThis);
                 enableSubstitutionsForCapturedThis();
-
                 return SuperCaptureResult.ReplaceSuperCapture;
             }
 

From fb4b503834456dd833b3c695a0248a228c7339cb Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Tue, 27 Sep 2016 14:36:17 -0700
Subject: [PATCH 41/47] Removed pointlessish overloads.

---
 src/compiler/transformers/es6.ts | 2 --
 1 file changed, 2 deletions(-)

diff --git a/src/compiler/transformers/es6.ts b/src/compiler/transformers/es6.ts
index b0633c309ea..481857e0536 100644
--- a/src/compiler/transformers/es6.ts
+++ b/src/compiler/transformers/es6.ts
@@ -1290,8 +1290,6 @@ namespace ts {
             }
         }
 
-        function captureThisForNode(statements: Statement[], node: Node, initializer: Expression | undefined): void;
-        function captureThisForNode(statements: Statement[], node: Node, initializer: Expression | undefined, originalStatement: Statement): void;
         function captureThisForNode(statements: Statement[], node: Node, initializer: Expression | undefined, originalStatement?: Statement): void {
             enableSubstitutionsForCapturedThis();
             const captureThisStatement = createVariableStatement(

From b5a10316851ec7943ab24ee6127178e705657f1c Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Tue, 27 Sep 2016 14:41:47 -0700
Subject: [PATCH 42/47] Moved code around, fixed indent, reworded comment.

---
 src/compiler/transformers/es6.ts | 129 +++++++++++++++----------------
 1 file changed, 64 insertions(+), 65 deletions(-)

diff --git a/src/compiler/transformers/es6.ts b/src/compiler/transformers/es6.ts
index 481857e0536..0495e422fc3 100644
--- a/src/compiler/transformers/es6.ts
+++ b/src/compiler/transformers/es6.ts
@@ -161,7 +161,7 @@ namespace ts {
          * Callers should skip the current statement and avoid any returns of '_this'.
          */
         ReplaceWithReturn,
-}
+    }
 
     export function transformES6(context: TransformationContext) {
         const {
@@ -902,7 +902,7 @@ namespace ts {
 
         /**
          * We want to try to avoid emitting a return statement in certain cases if a user already returned something.
-         * It would be pointless and generate dead code, so we'll try to make things a little bit prettier
+         * It would generate obviously dead code, so we'll try to make things a little bit prettier
          * by doing a minimal check on whether some common patterns always explicitly return.
          */
         function isSufficientlyCoveredByReturnStatements(statement: Statement): boolean {
@@ -910,7 +910,6 @@ namespace ts {
             if (statement.kind === SyntaxKind.ReturnStatement) {
                 return true;
             }
-
             // An if-statement with two covered branches is covered.
             else if (statement.kind === SyntaxKind.IfStatement) {
                 const ifStatement = statement as IfStatement;
@@ -973,6 +972,68 @@ namespace ts {
             return SuperCaptureResult.NoReplacement;
         }
 
+        /**
+         * Declares a `_this` variable for derived classes and for when arrow functions capture `this`.
+         *
+         * @returns The new statement offset into the `statements` array.
+         */
+        function declareOrCaptureOrReturnThisForConstructorIfNeeded(statements: Statement[], ctor: ConstructorDeclaration, hasExtendsClause: boolean, statementOffset: number) {
+            // If this isn't a derived class, just capture 'this' for arrow functions if necessary.
+            if (!hasExtendsClause) {
+                addCaptureThisForNodeIfNeeded(statements, ctor);
+                return SuperCaptureResult.NoReplacement;
+            }
+
+            // Most of the time, a 'super' call will be the first real statement in a constructor body.
+            // In these cases, we'd like to transform these into a *single* statement instead of a declaration
+            // followed by an assignment statement for '_this'. For instance, if we emitted without an initializer,
+            // we'd get:
+            //
+            //      var _this;
+            //      _this = _super.call(...) || this;
+            //
+            // instead of
+            //
+            //      var _this = _super.call(...) || this;
+            //
+            // Additionally, if the 'super()' call is the last statement, we should just avoid capturing
+            // entirely and immediately return the result like so:
+            //
+            //      return _super.call(...) || this;
+            //
+            let firstStatement: Statement;
+            let superCallExpression: Expression;
+
+            const ctorStatements = ctor.body.statements;
+            if (statementOffset < ctorStatements.length) {
+                firstStatement = ctorStatements[statementOffset];
+
+                if (firstStatement.kind === SyntaxKind.ExpressionStatement && isSuperCallExpression((firstStatement as ExpressionStatement).expression)) {
+                    const superCall = (firstStatement as ExpressionStatement).expression as CallExpression;
+                    superCallExpression = setOriginalNode(
+                        saveStateAndInvoke(superCall, visitImmediateSuperCallInBody),
+                        superCall
+                    );
+                }
+            }
+
+            // Return the result if we have an immediate super() call on the last statement.
+            if (superCallExpression && statementOffset === ctorStatements.length - 1) {
+                statements.push(createReturn(superCallExpression));
+                return SuperCaptureResult.ReplaceWithReturn;
+            }
+
+            // Perform the capture.
+            captureThisForNode(statements, ctor, superCallExpression, firstStatement);
+
+            // If we're actually replacing the original statement, we need to signal this to the caller.
+            if (superCallExpression) {
+                return SuperCaptureResult.ReplaceSuperCapture;
+            }
+
+            return SuperCaptureResult.NoReplacement;
+        }
+
         /**
          * Visits a parameter declaration.
          *
@@ -1216,68 +1277,6 @@ namespace ts {
             statements.push(forStatement);
         }
 
-        /**
-         * Declares a `_this` variable for derived classes and for when arrow functions capture `this`.
-         *
-         * @returns The new statement offset into the `statements` array.
-         */
-        function declareOrCaptureOrReturnThisForConstructorIfNeeded(statements: Statement[], ctor: ConstructorDeclaration, hasExtendsClause: boolean, statementOffset: number) {
-            // If this isn't a derived class, just capture 'this' for arrow functions if necessary.
-            if (!hasExtendsClause) {
-                addCaptureThisForNodeIfNeeded(statements, ctor);
-                return SuperCaptureResult.NoReplacement;
-            }
-
-            // Most of the time, a 'super' call will be the first real statement in a constructor body.
-            // In these cases, we'd like to transform these into a *single* statement instead of a declaration
-            // followed by an assignment statement for '_this'. For instance, if we emitted without an initializer,
-            // we'd get:
-            //
-            //      var _this;
-            //      _this = _super.call(...) || this;
-            //
-            // instead of
-            //
-            //      var _this = _super.call(...) || this;
-            //
-            // Additionally, if the 'super()' call is the last statement, we should just avoid capturing
-            // entirely and immediately return the result like so:
-            //
-            //      return _super.call(...) || this;
-            //
-            let firstStatement: Statement;
-            let superCallExpression: Expression;
-
-            const ctorStatements = ctor.body.statements;
-            if (statementOffset < ctorStatements.length) {
-                firstStatement = ctorStatements[statementOffset];
-
-                if (firstStatement.kind === SyntaxKind.ExpressionStatement && isSuperCallExpression((firstStatement as ExpressionStatement).expression)) {
-                    const superCall = (firstStatement as ExpressionStatement).expression as CallExpression;
-                    superCallExpression = setOriginalNode(
-                        saveStateAndInvoke(superCall, visitImmediateSuperCallInBody),
-                        superCall
-                    );
-                }
-            }
-
-            // Return the result if we have an immediate super() call on the last statement.
-            if (superCallExpression && statementOffset === ctorStatements.length - 1) {
-                statements.push(createReturn(superCallExpression));
-                return SuperCaptureResult.ReplaceWithReturn;
-            }
-
-            // Perform the capture.
-            captureThisForNode(statements, ctor, superCallExpression, firstStatement);
-
-            // If we're actually replacing the original statement, we need to signal this to the caller.
-            if (superCallExpression) {
-                return SuperCaptureResult.ReplaceSuperCapture;
-            }
-
-            return SuperCaptureResult.NoReplacement;
-        }
-
         /**
          * Adds a statement to capture the `this` of a function declaration if it is needed.
          *

From c29ec6fe371fb4c1ff2aed13a213ead2acfc961a Mon Sep 17 00:00:00 2001
From: Daniel Rosenwasser <Daniel.Rosenwasser@microsoft.com>
Date: Tue, 27 Sep 2016 20:53:15 -0700
Subject: [PATCH 43/47] Consolidated 'super()' transformation logic into one
 function.

---
 src/compiler/transformers/es6.ts | 88 ++++++++++++++------------------
 1 file changed, 38 insertions(+), 50 deletions(-)

diff --git a/src/compiler/transformers/es6.ts b/src/compiler/transformers/es6.ts
index 0495e422fc3..1ed7ee9b7ab 100644
--- a/src/compiler/transformers/es6.ts
+++ b/src/compiler/transformers/es6.ts
@@ -837,7 +837,6 @@ namespace ts {
             startLexicalEnvironment();
 
             let statementOffset = -1;
-            let superCaptureStatus = SuperCaptureResult.NoReplacement;
             if (hasSynthesizedSuper) {
                 // If a super call has already been synthesized,
                 // we're going to assume that we should just transform everything after that.
@@ -854,12 +853,9 @@ namespace ts {
                 addRestParameterIfNeeded(statements, constructor, hasSynthesizedSuper);
                 Debug.assert(statementOffset >= 0, "statementOffset not initialized correctly!");
 
-                superCaptureStatus = declareOrCaptureOrReturnThisForConstructorIfNeeded(statements, constructor, !!extendsClauseElement, statementOffset);
             }
 
-            if (superCaptureStatus === SuperCaptureResult.NoReplacement) {
-                superCaptureStatus = addDefaultSuperCallIfNeeded(statements, constructor, extendsClauseElement, hasSynthesizedSuper);
-            }
+            const superCaptureStatus = declareOrCaptureOrReturnThisForConstructorIfNeeded(statements, constructor, !!extendsClauseElement, hasSynthesizedSuper, statementOffset);
 
             // The last statement expression was replaced. Skip it.
             if (superCaptureStatus === SuperCaptureResult.ReplaceSuperCapture || superCaptureStatus === SuperCaptureResult.ReplaceWithReturn) {
@@ -929,61 +925,42 @@ namespace ts {
             return false;
         }
 
-        /**
-         * Adds a synthesized call to `_super` if it is needed.
-         *
-         * @param statements The statements for the new constructor body.
-         * @param constructor The constructor for the class.
-         * @param extendsClauseElement The expression for the class `extends` clause.
-         * @param hasSynthesizedSuper A value indicating whether the constructor starts with a
-         *                            synthesized `super` call.
-         */
-        function addDefaultSuperCallIfNeeded(statements: Statement[], constructor: ConstructorDeclaration, extendsClauseElement: ExpressionWithTypeArguments, hasSynthesizedSuper: boolean) {
-            // If the TypeScript transformer needed to synthesize a constructor for property
-            // initializers, it would have also added a synthetic `...args` parameter and
-            // `super` call.
-            // If this is the case, or if the class has an `extends` clause but no
-            // constructor, we emit a synthesized call to `_super`.
-            if (constructor ? hasSynthesizedSuper : extendsClauseElement) {
-                const actualThis = createThis();
-                setNodeEmitFlags(actualThis, NodeEmitFlags.NoSubstitution);
-                const superCall = createFunctionApply(
-                    createIdentifier("_super"),
-                    actualThis,
-                    createIdentifier("arguments"),
-                );
-                const superReturnValueOrThis = createLogicalOr(superCall, actualThis);
-
-                if (!constructor) {
-                    // We must be here because the user didn't write a constructor
-                    // but we needed to call 'super()' anyway - but if that's the case,
-                    // we can just immediately return the result of a 'super()' call.
-                    statements.push(createReturn(superReturnValueOrThis));
-                    return SuperCaptureResult.ReplaceWithReturn;
-                }
-
-                // The constructor was generated for some reason.
-                // Create a captured '_this' variable.
-                captureThisForNode(statements, constructor, superReturnValueOrThis);
-                enableSubstitutionsForCapturedThis();
-                return SuperCaptureResult.ReplaceSuperCapture;
-            }
-
-            return SuperCaptureResult.NoReplacement;
-        }
-
         /**
          * Declares a `_this` variable for derived classes and for when arrow functions capture `this`.
          *
          * @returns The new statement offset into the `statements` array.
          */
-        function declareOrCaptureOrReturnThisForConstructorIfNeeded(statements: Statement[], ctor: ConstructorDeclaration, hasExtendsClause: boolean, statementOffset: number) {
+        function declareOrCaptureOrReturnThisForConstructorIfNeeded(
+                    statements: Statement[],
+                    ctor: ConstructorDeclaration | undefined,
+                    hasExtendsClause: boolean,
+                    hasSynthesizedSuper: boolean,
+                    statementOffset: number) {
             // If this isn't a derived class, just capture 'this' for arrow functions if necessary.
             if (!hasExtendsClause) {
-                addCaptureThisForNodeIfNeeded(statements, ctor);
+                if (ctor) {
+                    addCaptureThisForNodeIfNeeded(statements, ctor);
+                }
                 return SuperCaptureResult.NoReplacement;
             }
 
+            // We must be here because the user didn't write a constructor
+            // but we needed to call 'super(...args)' anyway as per 14.5.14 of the ES2016 spec.
+            // If that's the case we can just immediately return the result of a 'super()' call.
+            if (!ctor) {
+                statements.push(createReturn(createDefaultSuperCallOrThis()));
+                return SuperCaptureResult.ReplaceWithReturn;
+            }
+
+            // The constructor exists, but it and the 'super()' call it contains were generated
+            // for something like property initializers.
+            // Create a captured '_this' variable and assume it will subsequently be used.
+            if (hasSynthesizedSuper) {
+                captureThisForNode(statements, ctor, createDefaultSuperCallOrThis());
+                enableSubstitutionsForCapturedThis();
+                return SuperCaptureResult.ReplaceSuperCapture;
+            }
+
             // Most of the time, a 'super' call will be the first real statement in a constructor body.
             // In these cases, we'd like to transform these into a *single* statement instead of a declaration
             // followed by an assignment statement for '_this'. For instance, if we emitted without an initializer,
@@ -1034,6 +1011,17 @@ namespace ts {
             return SuperCaptureResult.NoReplacement;
         }
 
+        function createDefaultSuperCallOrThis() {
+            const actualThis = createThis();
+            setNodeEmitFlags(actualThis, NodeEmitFlags.NoSubstitution);
+            const superCall = createFunctionApply(
+                createIdentifier("_super"),
+                actualThis,
+                createIdentifier("arguments"),
+            );
+            return createLogicalOr(superCall, actualThis);
+        }
+
         /**
          * Visits a parameter declaration.
          *

From f03be92e7d12fd32ab9a5f38cc80abdb492595c2 Mon Sep 17 00:00:00 2001
From: Ron Buckton <rbuckton@microsoft.com>
Date: Wed, 28 Sep 2016 18:57:17 -0700
Subject: [PATCH 44/47] Remove ConstantValue flag, comment cleanup.

---
 src/compiler/emitter.ts   |  4 ++--
 src/compiler/factory.ts   | 15 +++++++++------
 src/compiler/sourcemap.ts |  2 +-
 src/compiler/types.ts     |  1 -
 4 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/src/compiler/emitter.ts b/src/compiler/emitter.ts
index 6ad91069033..6049b004b0b 100644
--- a/src/compiler/emitter.ts
+++ b/src/compiler/emitter.ts
@@ -413,7 +413,7 @@ const _super = (function (geti, seti) {
          *
          * NOTE: Do not call this method directly. It is part of the emit pipeline
          * and should only be called indirectly from pipelineEmitWithSourceMap or
-         * pipelineEmitInUnspecifiedContext (when pickign a more specific context).
+         * pipelineEmitInUnspecifiedContext (when picking a more specific context).
          */
         function pipelineEmitWithSubstitution(emitContext: EmitContext, node: Node) {
             emitNodeWithSubstitution(emitContext, node, pipelineEmitForContext);
@@ -1172,7 +1172,7 @@ const _super = (function (geti, seti) {
                 const text = getLiteralTextOfNode(<LiteralExpression>expression);
                 return text.indexOf(tokenToString(SyntaxKind.DotToken)) < 0;
             }
-            else {
+            else if (isPropertyAccessExpression(expression) || isElementAccessExpression(expression)) {
                 // check if constant enum value is integer
                 const constantValue = getConstantValue(expression);
                 // isFinite handles cases when constantValue is undefined
diff --git a/src/compiler/factory.ts b/src/compiler/factory.ts
index fd00a051dcb..d873c3ef877 100644
--- a/src/compiler/factory.ts
+++ b/src/compiler/factory.ts
@@ -2798,17 +2798,20 @@ namespace ts {
         return tokenSourceMapRanges && tokenSourceMapRanges[token];
     }
 
-    export function getConstantValue(node: Node) {
+    /**
+     * Gets the constant value to emit for an expression.
+     */
+    export function getConstantValue(node: PropertyAccessExpression | ElementAccessExpression) {
         const emitNode = node.emitNode;
-        if (emitNode && emitNode.flags & EmitFlags.ConstantValue) {
-            return emitNode.constantValue;
-        }
+        return emitNode && emitNode.constantValue;
     }
 
-    export function setConstantValue(node: Node, value: number) {
+    /**
+     * Sets the constant value to emit for an expression.
+     */
+    export function setConstantValue(node: PropertyAccessExpression | ElementAccessExpression, value: number) {
         const emitNode = getOrCreateEmitNode(node);
         emitNode.constantValue = value;
-        emitNode.flags |= EmitFlags.ConstantValue;
         return node;
     }
 
diff --git a/src/compiler/sourcemap.ts b/src/compiler/sourcemap.ts
index d6e6501c598..46db5188e33 100644
--- a/src/compiler/sourcemap.ts
+++ b/src/compiler/sourcemap.ts
@@ -348,7 +348,7 @@ namespace ts {
         }
 
         /**
-         * Emits a token of a node node with possible leading and trailing source maps.
+         * Emits a token of a node with possible leading and trailing source maps.
          *
          * @param node The node containing the token.
          * @param token The token to emit.
diff --git a/src/compiler/types.ts b/src/compiler/types.ts
index 316f8b2b2c0..192367348db 100644
--- a/src/compiler/types.ts
+++ b/src/compiler/types.ts
@@ -3205,7 +3205,6 @@ namespace ts {
         AsyncFunctionBody = 1 << 21,
         ReuseTempVariableScope = 1 << 22,        // Reuse the existing temp variable scope during emit.
         CustomPrologue = 1 << 23,                // Treat the statement as if it were a prologue directive (NOTE: Prologue directives are *not* transformed).
-        ConstantValue = 1 << 24,                 // The node was replaced with a constant value during substitution.
     }
 
     /* @internal */

From 228ddde66ea7ca92e255da183a61a06dacf4bfd6 Mon Sep 17 00:00:00 2001
From: Andy Hanson <anhans@microsoft.com>
Date: Thu, 29 Sep 2016 06:15:48 -0700
Subject: [PATCH 45/47] Ensure that `checkGrammarModuleElementContext` reliably
 returns `true` when there is bad grammar.

---
 src/compiler/checker.ts                               | 8 +++++---
 tests/baselines/reference/exportInFunction.errors.txt | 9 +++++++++
 tests/baselines/reference/exportInFunction.js         | 9 +++++++++
 tests/cases/compiler/exportInFunction.ts              | 2 ++
 4 files changed, 25 insertions(+), 3 deletions(-)
 create mode 100644 tests/baselines/reference/exportInFunction.errors.txt
 create mode 100644 tests/baselines/reference/exportInFunction.js
 create mode 100644 tests/cases/compiler/exportInFunction.ts

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 61cf701eb95..1f50ace2cf1 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -17706,9 +17706,11 @@ namespace ts {
         }
 
         function checkGrammarModuleElementContext(node: Statement, errorMessage: DiagnosticMessage): boolean {
-            if (node.parent.kind !== SyntaxKind.SourceFile && node.parent.kind !== SyntaxKind.ModuleBlock && node.parent.kind !== SyntaxKind.ModuleDeclaration) {
-                return grammarErrorOnFirstToken(node, errorMessage);
+            const isInAppropriateContext = node.parent.kind === SyntaxKind.SourceFile || node.parent.kind === SyntaxKind.ModuleBlock || node.parent.kind === SyntaxKind.ModuleDeclaration;
+            if (!isInAppropriateContext) {
+                grammarErrorOnFirstToken(node, errorMessage);
             }
+            return !isInAppropriateContext;
         }
 
         function checkExportSpecifier(node: ExportSpecifier) {
@@ -17749,7 +17751,7 @@ namespace ts {
                 checkExpressionCached(node.expression);
             }
 
-            checkExternalModuleExports(<SourceFile | ModuleDeclaration>container);
+            checkExternalModuleExports(container);
 
             if (node.isExportEquals && !isInAmbientContext(node)) {
                 if (modulekind === ModuleKind.ES6) {
diff --git a/tests/baselines/reference/exportInFunction.errors.txt b/tests/baselines/reference/exportInFunction.errors.txt
new file mode 100644
index 00000000000..cfd005952f9
--- /dev/null
+++ b/tests/baselines/reference/exportInFunction.errors.txt
@@ -0,0 +1,9 @@
+tests/cases/compiler/exportInFunction.ts(3,1): error TS1005: '}' expected.
+
+
+==== tests/cases/compiler/exportInFunction.ts (1 errors) ====
+    function f() {
+        export = 0;
+    
+    
+!!! error TS1005: '}' expected.
\ No newline at end of file
diff --git a/tests/baselines/reference/exportInFunction.js b/tests/baselines/reference/exportInFunction.js
new file mode 100644
index 00000000000..9e1db163d81
--- /dev/null
+++ b/tests/baselines/reference/exportInFunction.js
@@ -0,0 +1,9 @@
+//// [exportInFunction.ts]
+function f() {
+    export = 0;
+
+
+//// [exportInFunction.js]
+function f() {
+    export = 0;
+}
diff --git a/tests/cases/compiler/exportInFunction.ts b/tests/cases/compiler/exportInFunction.ts
new file mode 100644
index 00000000000..9bb0c5dcd0f
--- /dev/null
+++ b/tests/cases/compiler/exportInFunction.ts
@@ -0,0 +1,2 @@
+function f() {
+    export = 0;

From 8177bd4da076be73d07bd3dba8c16a88aac3ba58 Mon Sep 17 00:00:00 2001
From: Vladimir Matveev <vladima@microsoft.com>
Date: Fri, 30 Sep 2016 13:19:54 -0700
Subject: [PATCH 46/47] replace hardcodes 'useCaseSensitiveFileNames=false' in
 services with actual value, use specialized map lookup methods instead of
 generic 'getOrCreate*'

---
 src/harness/unittests/tsserverProjectSystem.ts | 18 ++++++++++++++++++
 src/server/editorServices.ts                   |  7 ++++++-
 src/server/project.ts                          |  8 +++++++-
 src/services/services.ts                       |  2 +-
 4 files changed, 32 insertions(+), 3 deletions(-)

diff --git a/src/harness/unittests/tsserverProjectSystem.ts b/src/harness/unittests/tsserverProjectSystem.ts
index c459d2afac2..988e87284c3 100644
--- a/src/harness/unittests/tsserverProjectSystem.ts
+++ b/src/harness/unittests/tsserverProjectSystem.ts
@@ -2045,4 +2045,22 @@ namespace ts.projectSystem {
             assert.equal(snap.getLength(), expectedLength, "Incorrect snapshot size");
         }
     });
+
+    describe("Language service", () => {
+        it("should work correctly on case-sensitive file systems", () => {
+            const lib = {
+                path: "/a/Lib/lib.d.ts",
+                content: "let x: number"
+            };
+            const f = {
+                path: "/a/b/app.ts",
+                content: "let x = 1;"
+            };
+            const host = createServerHost([lib, f], { executingFilePath: "/a/Lib/tsc.js", useCaseSensitiveFileNames: true });
+            const projectService = createProjectService(host);
+            projectService.openClientFile(f.path);
+            projectService.checkNumberOfProjects({ inferredProjects: 1 });
+            projectService.inferredProjects[0].getLanguageService().getProgram();
+        });
+    });
 }
\ No newline at end of file
diff --git a/src/server/editorServices.ts b/src/server/editorServices.ts
index 707f286a9b5..2b28e66bf88 100644
--- a/src/server/editorServices.ts
+++ b/src/server/editorServices.ts
@@ -1001,9 +1001,14 @@ namespace ts.server {
         }
 
         getScriptInfoForNormalizedPath(fileName: NormalizedPath) {
-            return this.filenameToScriptInfo.get(normalizedPathToPath(fileName, this.host.getCurrentDirectory(), this.toCanonicalFileName));
+            return this.getScriptInfoForPath(normalizedPathToPath(fileName, this.host.getCurrentDirectory(), this.toCanonicalFileName));
         }
 
+        getScriptInfoForPath(fileName: Path) {
+            return this.filenameToScriptInfo.get(fileName);
+        }
+
+
         setHostConfiguration(args: protocol.ConfigureRequestArguments) {
             if (args.file) {
                 const info = this.getScriptInfoForNormalizedPath(toNormalizedPath(args.file));
diff --git a/src/server/project.ts b/src/server/project.ts
index 01858b4cc68..b59efb03cfd 100644
--- a/src/server/project.ts
+++ b/src/server/project.ts
@@ -215,7 +215,13 @@ namespace ts.server {
         }
 
         getScriptInfos() {
-            return map(this.program.getSourceFiles(), sourceFile => this.getScriptInfoLSHost(sourceFile.path));
+            return map(this.program.getSourceFiles(), sourceFile => {
+                const scriptInfo = this.projectService.getScriptInfoForPath(sourceFile.path);
+                if (!scriptInfo) {
+                    Debug.assert(false, `scriptInfo for a file '${sourceFile.fileName}' is missing.`);
+                }
+                return scriptInfo;
+            });
         }
 
         getFileEmitOutput(info: ScriptInfo, emitOnlyDtsFiles: boolean) {
diff --git a/src/services/services.ts b/src/services/services.ts
index eb103cebb11..b50e1d3313d 100644
--- a/src/services/services.ts
+++ b/src/services/services.ts
@@ -947,7 +947,7 @@ namespace ts {
 
         let lastTypesRootVersion = 0;
 
-        const useCaseSensitivefileNames = false;
+        const useCaseSensitivefileNames = host.useCaseSensitiveFileNames && host.useCaseSensitiveFileNames();
         const cancellationToken = new CancellationTokenObject(host.getCancellationToken && host.getCancellationToken());
 
         const currentDirectory = host.getCurrentDirectory();

From ae7f1be42766150366dcdcad9273f2827da68f32 Mon Sep 17 00:00:00 2001
From: Ron Buckton <rbuckton@microsoft.com>
Date: Fri, 30 Sep 2016 14:20:06 -0700
Subject: [PATCH 47/47] Do not emit extra var decls for merged enums/namespaces

---
 src/compiler/transformers/ts.ts               |  75 +-
 ...hModuleMemberThatUsesClassTypeParameter.js |   4 -
 ...GenericClassStaticFunctionOfTheSameName.js |   1 -
 ...GenericClassStaticFunctionOfTheSameName.js |   1 -
 ...dStaticFunctionUsingClassPrivateStatics.js |   1 -
 ...nctionAndExportedFunctionThatShareAName.js |   2 -
 ...ionAndNonExportedFunctionThatShareAName.js |   2 -
 ...ticVariableAndExportedVarThatShareAName.js |   2 -
 ...VariableAndNonExportedVarThatShareAName.js |   2 -
 ...ClassAndModuleWithSameNameAndCommonRoot.js |   1 -
 .../EnumAndModuleWithSameNameAndCommonRoot.js |   1 -
 ...ctionAndModuleWithSameNameAndCommonRoot.js |   1 -
 .../ModuleAndEnumWithSameNameAndCommonRoot.js |   1 -
 ...ortedAndNonExportedClassesOfTheSameName.js |   2 -
 ...rgeEachWithExportedClassesOfTheSameName.js |   2 -
 ...rgeEachWithExportedModulesOfTheSameName.js |   2 -
 .../anyAssignabilityInInheritance.js          |   2 -
 .../reference/anyAssignableToEveryType2.js    |   2 -
 ...entCompatWithObjectMembersAccessibility.js |   1 -
 .../assignmentToObjectAndFunction.js          |   3 -
 .../reference/augmentExportEquals3.js         |   1 -
 .../reference/augmentExportEquals4.js         |   1 -
 .../reference/augmentExportEquals6.js         |   1 -
 .../reference/augmentedTypesClass.js          |   1 -
 .../reference/augmentedTypesClass2.js         |   1 -
 .../reference/augmentedTypesClass3.js         |   2 -
 .../baselines/reference/augmentedTypesEnum.js |   4 -
 .../reference/augmentedTypesEnum3.js          |   5 -
 .../reference/augmentedTypesFunction.js       |   3 -
 .../reference/augmentedTypesModules.js        |   7 -
 .../reference/augmentedTypesModules2.js       |   2 -
 .../reference/augmentedTypesModules3b.js      |   2 -
 .../reference/augmentedTypesModules4.js       |   3 -
 .../reference/autonumberingInEnums.js         |   1 -
 ...ureWithoutReturnTypeAnnotationInference.js |   3 -
 .../circularTypeofWithFunctionModule.js       |   1 -
 ...clarationMergedInModuleWithContinuation.js |   2 -
 ...sMergedWithModuleNotReferingConstructor.js |   1 -
 .../cloduleAcrossModuleDefinitions.js         |   1 -
 .../reference/cloduleAndTypeParameters.js     |   1 -
 .../reference/cloduleStaticMembers.js         |   1 -
 .../reference/cloduleWithDuplicateMember1.js  |   2 -
 .../reference/cloduleWithDuplicateMember2.js  |   2 -
 .../cloduleWithPriorInstantiatedModule.js     |   1 -
 .../cloduleWithPriorUninstantiatedModule.js   |   1 -
 .../cloduleWithRecursiveReference.js          |   1 -
 .../reference/clodulesDerivedClasses.js       |   2 -
 ...lisionCodeGenModuleWithAccessorChildren.js |   4 -
 ...ionCodeGenModuleWithConstructorChildren.js |   2 -
 ...lisionCodeGenModuleWithFunctionChildren.js |   2 -
 ...ollisionCodeGenModuleWithMethodChildren.js |   3 -
 ...ollisionCodeGenModuleWithModuleChildren.js |   4 -
 ...llisionCodeGenModuleWithModuleReopening.js |   2 -
 .../reference/commentsMultiModuleMultiFile.js |   1 -
 .../commentsMultiModuleSingleFile.js          |   1 -
 .../constructSignaturesWithOverloads2.js      |   2 -
 .../reference/declFileGenericType2.js         |   1 -
 .../declFileTypeAnnotationTypeAlias.js        |   1 -
 ...lictingWithClassReferredByExtendsClause.js |   1 -
 ...dsClauseThatHasItsContainerNameConflict.js |   1 -
 .../reference/declarationEmitNameConflicts.js |   2 -
 .../declarationEmitNameConflicts2.js          |   1 -
 .../declarationEmitNameConflicts3.js          |   1 -
 tests/baselines/reference/dottedModuleName.js |   1 -
 .../baselines/reference/dottedModuleName2.js  |   1 -
 .../reference/duplicateAnonymousInners1.js    |   1 -
 .../duplicateAnonymousModuleClasses.js        |   3 -
 ...ateIdentifiersAcrossContainerBoundaries.js |   9 -
 .../duplicateSymbolsExportMatching.js         |   4 -
 .../enumAssignabilityInInheritance.js         |   2 -
 .../reference/enumAssignmentCompat.js         |   1 -
 .../reference/enumAssignmentCompat2.js        |   1 -
 .../reference/enumAssignmentCompat3.js        |   1 -
 tests/baselines/reference/enumBasics1.js      |   1 -
 .../reference/enumGenericTypeClash.js         |   1 -
 .../enumIsNotASubtypeOfAnythingButNumber.js   |   2 -
 tests/baselines/reference/enumMerging.js      |   3 -
 .../baselines/reference/enumMergingErrors.js  |   6 -
 .../enumsWithMultipleDeclarations1.js         |   2 -
 .../enumsWithMultipleDeclarations2.js         |   2 -
 .../reference/es6modulekindWithES5Target12.js |  70 ++
 .../es6modulekindWithES5Target12.symbols      |  62 ++
 .../es6modulekindWithES5Target12.types        |  69 ++
 .../reference/exportAssignmentMergedModule.js |   1 -
 .../exportAssignmentTopLevelClodule.js        |   1 -
 .../exportAssignmentTopLevelEnumdule.js       |   1 -
 .../exportAssignmentTopLevelFundule.js        |   1 -
 .../exportDeclarationInInternalModule.js      |   2 -
 .../reference/exportDefaultProperty.js        |   1 -
 .../reference/exportEqualsProperty.js         |   1 -
 .../baselines/reference/exportImportAlias.js  |   2 -
 .../reference/exportImportAndClodule.js       |   1 -
 tests/baselines/reference/extBaseClass1.js    |   1 -
 tests/baselines/reference/forwardRefInEnum.js |   1 -
 tests/baselines/reference/funClodule.js       |   1 -
 .../reference/functionMergedWithModule.js     |   2 -
 ...leOfFunctionWithoutReturnTypeAnnotation.js |   1 -
 .../reference/genericCloduleInModule.js       |   1 -
 .../reference/genericCloduleInModule2.js      |   1 -
 ...genericConstraintOnExtendedBuiltinTypes.js |   1 -
 ...enericConstraintOnExtendedBuiltinTypes2.js |   1 -
 .../reference/genericFunduleInModule.js       |   1 -
 .../reference/genericFunduleInModule2.js      |   1 -
 ...ericMergedDeclarationUsingTypeParameter.js |   1 -
 ...ricMergedDeclarationUsingTypeParameter2.js |   1 -
 .../reference/genericOfACloduleType1.js       |   1 -
 .../reference/genericOfACloduleType2.js       |   1 -
 ...ericRecursiveImplicitConstructorErrors3.js |   1 -
 .../reference/heterogeneousArrayLiterals.js   |   1 -
 .../reference/importAliasIdentifiers.js       |   2 -
 .../inheritedModuleMembersForClodule.js       |   1 -
 ...leMergedWithClassNotReferencingInstance.js |   1 -
 ...thClassNotReferencingInstanceNoConflict.js |   1 -
 .../reference/invalidNestedModules.js         |   2 -
 .../isDeclarationVisibleNodeKinds.js          |   8 -
 .../reference/mergeThreeInterfaces2.js        |   4 -
 .../reference/mergeTwoInterfaces2.js          |   3 -
 .../reference/mergedDeclarations1.js          |   1 -
 .../reference/mergedDeclarations2.js          |   2 -
 .../reference/mergedDeclarations3.js          |   5 -
 .../reference/mergedDeclarations4.js          |   1 -
 .../reference/mergedEnumDeclarationCodeGen.js |   1 -
 .../mergedModuleDeclarationCodeGen.js         |   1 -
 .../mergedModuleDeclarationCodeGen2.js        |   1 -
 .../mergedModuleDeclarationCodeGen3.js        |   1 -
 .../mergedModuleDeclarationCodeGen4.js        |   1 -
 .../mergedModuleDeclarationCodeGen5.js        |   1 -
 ...dModuleDeclarationWithSharedExportedVar.js |   1 -
 .../missingFunctionImplementation.js          |   4 -
 .../reference/moduleDuplicateIdentifiers.js   |   1 -
 .../moduleMemberWithoutTypeAnnotation1.js     |   3 -
 tests/baselines/reference/moduleMerge.js      |   1 -
 .../reference/moduleReopenedTypeOtherBlock.js |   1 -
 .../reference/moduleReopenedTypeSameBlock.js  |   1 -
 tests/baselines/reference/moduleVariables.js  |   2 -
 .../reference/moduleVisibilityTest1.js        |   1 -
 .../reference/moduleVisibilityTest2.js        |   1 -
 tests/baselines/reference/moduledecl.js       |   1 -
 .../reference/multiModuleClodule1.js          |   2 -
 .../reference/multiModuleFundule1.js          |   2 -
 tests/baselines/reference/multipleExports.js  |   1 -
 tests/baselines/reference/nameCollision.js    |   1 -
 .../nameCollisionWithBlockScopedVariable1.js  |   1 -
 .../nonExportedElementsOfMergedModules.js     |   1 -
 .../nullIsSubtypeOfEverythingButUndefined.js  |   2 -
 ...ectLiteralShorthandPropertiesWithModule.js |   1 -
 ...LiteralShorthandPropertiesWithModuleES6.js |   1 -
 .../reference/parserEnumDeclaration4.js       |   1 -
 ...privacyCheckAnonymousFunctionParameter2.js |   1 -
 ...rtAssignmentOnExportedGenericInterface2.js |   1 -
 tests/baselines/reference/privacyImport.js    |   1 -
 .../reference/privacyImportParseErrors.js     |   1 -
 .../privateStaticNotAccessibleInClodule.js    |   1 -
 .../privateStaticNotAccessibleInClodule2.js   |   1 -
 .../protectedStaticNotAccessibleInClodule.js  |   1 -
 tests/baselines/reference/qualify.js          |   1 -
 .../reference/recursiveClassReferenceTest.js  |   2 -
 .../recursiveClassReferenceTest.js.map        |   2 +-
 .../recursiveClassReferenceTest.sourcemap.txt | 666 ++++++++----------
 .../reference/recursiveCloduleReference.js    |   1 -
 tests/baselines/reference/recursiveMods.js    |   1 -
 tests/baselines/reference/reservedWords2.js   |   1 -
 ...lassDeclarationWhenInBaseTypeResolution.js |  37 -
 .../sourcemapValidationDuplicateNames.js      |   1 -
 .../sourcemapValidationDuplicateNames.js.map  |   2 +-
 ...emapValidationDuplicateNames.sourcemap.txt |  63 +-
 .../reference/staticMemberExportAccess.js     |   1 -
 .../reference/staticPropertyNotInClassType.js |   2 -
 .../reference/staticsNotInScopeInClodule.js   |   1 -
 tests/baselines/reference/subtypesOfAny.js    |   2 -
 .../reference/subtypesOfTypeParameter.js      |   2 -
 ...subtypesOfTypeParameterWithConstraints2.js |   2 -
 tests/baselines/reference/subtypesOfUnion.js  |   2 -
 .../systemModuleDeclarationMerging.js         |   2 +-
 tests/baselines/reference/tsxEmit3.js         |   3 -
 tests/baselines/reference/tsxEmit3.js.map     |   2 +-
 .../reference/tsxEmit3.sourcemap.txt          | 310 ++++----
 tests/baselines/reference/tsxPreserveEmit1.js |   1 -
 tests/baselines/reference/tsxReactEmit6.js    |   1 -
 .../typeOfEnumAndVarRedeclarations.js         |   1 -
 .../reference/typeofANonExportedType.js       |   1 -
 .../reference/typeofAnExportedType.js         |   1 -
 .../undefinedIsSubtypeOfEverything.js         |   2 -
 .../reference/undefinedTypeAssignment4.js     |   1 -
 .../unexportedInstanceClassVariables.js       |   1 -
 ...nSubtypeIfEveryConstituentTypeIsSubtype.js |   2 -
 ...flictsWithImportInDifferentPartOfModule.js |   1 -
 .../compiler/es6modulekindWithES5Target12.ts  |  39 +
 188 files changed, 749 insertions(+), 943 deletions(-)
 create mode 100644 tests/baselines/reference/es6modulekindWithES5Target12.js
 create mode 100644 tests/baselines/reference/es6modulekindWithES5Target12.symbols
 create mode 100644 tests/baselines/reference/es6modulekindWithES5Target12.types
 create mode 100644 tests/cases/compiler/es6modulekindWithES5Target12.ts

diff --git a/src/compiler/transformers/ts.ts b/src/compiler/transformers/ts.ts
index 054b1e4608b..f6e8074cb07 100644
--- a/src/compiler/transformers/ts.ts
+++ b/src/compiler/transformers/ts.ts
@@ -51,6 +51,7 @@ namespace ts {
         let currentNamespace: ModuleDeclaration;
         let currentNamespaceContainerName: Identifier;
         let currentScope: SourceFile | Block | ModuleBlock | CaseBlock;
+        let currentScopeFirstDeclarationsOfName: Map<Node>;
         let currentSourceFileExternalHelpersModuleName: Identifier;
 
         /**
@@ -100,6 +101,7 @@ namespace ts {
         function saveStateAndInvoke<T>(node: Node, f: (node: Node) => T): T {
             // Save state
             const savedCurrentScope = currentScope;
+            const savedCurrentScopeFirstDeclarationsOfName = currentScopeFirstDeclarationsOfName;
 
             // Handle state changes before visiting a node.
             onBeforeVisitNode(node);
@@ -107,8 +109,11 @@ namespace ts {
             const visited = f(node);
 
             // Restore state
-            currentScope = savedCurrentScope;
+            if (currentScope !== savedCurrentScope) {
+                currentScopeFirstDeclarationsOfName = savedCurrentScopeFirstDeclarationsOfName;
+            }
 
+            currentScope = savedCurrentScope;
             return visited;
         }
 
@@ -414,6 +419,16 @@ namespace ts {
                 case SyntaxKind.ModuleBlock:
                 case SyntaxKind.Block:
                     currentScope = <SourceFile | CaseBlock | ModuleBlock | Block>node;
+                    currentScopeFirstDeclarationsOfName = undefined;
+                    break;
+
+                case SyntaxKind.ClassDeclaration:
+                case SyntaxKind.FunctionDeclaration:
+                    if (hasModifier(node, ModifierFlags.Ambient)) {
+                        break;
+                    }
+
+                    recordEmittedDeclarationInScope(node);
                     break;
             }
         }
@@ -2502,10 +2517,12 @@ namespace ts {
         }
 
         function shouldEmitVarForEnumDeclaration(node: EnumDeclaration | ModuleDeclaration) {
-            return !hasModifier(node, ModifierFlags.Export)
-                || (isES6ExportedDeclaration(node) && isFirstDeclarationOfKind(node, node.kind));
+            return isFirstEmittedDeclarationInScope(node)
+                && (!hasModifier(node, ModifierFlags.Export)
+                    || isES6ExportedDeclaration(node));
         }
 
+
         /*
          * Adds a trailing VariableStatement for an enum or module declaration.
          */
@@ -2543,6 +2560,7 @@ namespace ts {
             // If needed, we should emit a variable declaration for the enum. If we emit
             // a leading variable declaration, we should not emit leading comments for the
             // enum body.
+            recordEmittedDeclarationInScope(node);
             if (shouldEmitVarForEnumDeclaration(node)) {
                 addVarForEnumOrModuleDeclaration(statements, node);
 
@@ -2679,20 +2697,48 @@ namespace ts {
             return isInstantiatedModule(node, compilerOptions.preserveConstEnums || compilerOptions.isolatedModules);
         }
 
-        function isModuleMergedWithES6Class(node: ModuleDeclaration) {
-            return languageVersion === ScriptTarget.ES6
-                && isMergedWithClass(node);
-        }
-
         function isES6ExportedDeclaration(node: Node) {
             return isExternalModuleExport(node)
                 && moduleKind === ModuleKind.ES6;
         }
 
+        /**
+         * Records that a declaration was emitted in the current scope, if it was the first
+         * declaration for the provided symbol.
+         *
+         * NOTE: if there is ever a transformation above this one, we may not be able to rely
+         *       on symbol names.
+         */
+        function recordEmittedDeclarationInScope(node: Node) {
+            const name = node.symbol && node.symbol.name;
+            if (name) {
+                if (!currentScopeFirstDeclarationsOfName) {
+                    currentScopeFirstDeclarationsOfName = createMap<Node>();
+                }
+
+                if (!(name in currentScopeFirstDeclarationsOfName)) {
+                    currentScopeFirstDeclarationsOfName[name] = node;
+                }
+            }
+        }
+
+        /**
+         * Determines whether a declaration is the first declaration with the same name emitted
+         * in the current scope.
+         */
+        function isFirstEmittedDeclarationInScope(node: Node) {
+            if (currentScopeFirstDeclarationsOfName) {
+                const name = node.symbol && node.symbol.name;
+                if (name) {
+                    return currentScopeFirstDeclarationsOfName[name] === node;
+                }
+            }
+
+            return false;
+        }
+
         function shouldEmitVarForModuleDeclaration(node: ModuleDeclaration) {
-            return !isModuleMergedWithES6Class(node)
-                && (!isES6ExportedDeclaration(node)
-                    || isFirstDeclarationOfKind(node, node.kind));
+            return isFirstEmittedDeclarationInScope(node);
         }
 
         /**
@@ -2768,6 +2814,7 @@ namespace ts {
             // If needed, we should emit a variable declaration for the module. If we emit
             // a leading variable declaration, we should not emit leading comments for the
             // module body.
+            recordEmittedDeclarationInScope(node);
             if (shouldEmitVarForModuleDeclaration(node)) {
                 addVarForEnumOrModuleDeclaration(statements, node);
                 // We should still emit the comments if we are emitting a system module.
@@ -2837,8 +2884,10 @@ namespace ts {
         function transformModuleBody(node: ModuleDeclaration, namespaceLocalName: Identifier): Block {
             const savedCurrentNamespaceContainerName = currentNamespaceContainerName;
             const savedCurrentNamespace = currentNamespace;
+            const savedCurrentScopeFirstDeclarationsOfName = currentScopeFirstDeclarationsOfName;
             currentNamespaceContainerName = namespaceLocalName;
             currentNamespace = node;
+            currentScopeFirstDeclarationsOfName = undefined;
 
             const statements: Statement[] = [];
             startLexicalEnvironment();
@@ -2865,10 +2914,12 @@ namespace ts {
                 const moduleBlock = <ModuleBlock>getInnerMostModuleDeclarationFromDottedModule(node).body;
                 statementsLocation = moveRangePos(moduleBlock.statements, -1);
             }
-            addRange(statements, endLexicalEnvironment());
 
+            addRange(statements, endLexicalEnvironment());
             currentNamespaceContainerName = savedCurrentNamespaceContainerName;
             currentNamespace = savedCurrentNamespace;
+            currentScopeFirstDeclarationsOfName = savedCurrentScopeFirstDeclarationsOfName;
+
             const block = createBlock(
                 createNodeArray(
                     statements,
diff --git a/tests/baselines/reference/ClassAndModuleThatMergeWithModuleMemberThatUsesClassTypeParameter.js b/tests/baselines/reference/ClassAndModuleThatMergeWithModuleMemberThatUsesClassTypeParameter.js
index bf9875efe30..09f7befae07 100644
--- a/tests/baselines/reference/ClassAndModuleThatMergeWithModuleMemberThatUsesClassTypeParameter.js
+++ b/tests/baselines/reference/ClassAndModuleThatMergeWithModuleMemberThatUsesClassTypeParameter.js
@@ -56,7 +56,6 @@ var clodule1 = (function () {
     }
     return clodule1;
 }());
-var clodule1;
 (function (clodule1) {
     function f(x) { }
 })(clodule1 || (clodule1 = {}));
@@ -65,7 +64,6 @@ var clodule2 = (function () {
     }
     return clodule2;
 }());
-var clodule2;
 (function (clodule2) {
     var x;
     var D = (function () {
@@ -79,7 +77,6 @@ var clodule3 = (function () {
     }
     return clodule3;
 }());
-var clodule3;
 (function (clodule3) {
     clodule3.y = { id: T };
 })(clodule3 || (clodule3 = {}));
@@ -88,7 +85,6 @@ var clodule4 = (function () {
     }
     return clodule4;
 }());
-var clodule4;
 (function (clodule4) {
     var D = (function () {
         function D() {
diff --git a/tests/baselines/reference/ClassAndModuleThatMergeWithModulesExportedGenericFunctionAndGenericClassStaticFunctionOfTheSameName.js b/tests/baselines/reference/ClassAndModuleThatMergeWithModulesExportedGenericFunctionAndGenericClassStaticFunctionOfTheSameName.js
index dc6c6f6ee8e..6e12244542e 100644
--- a/tests/baselines/reference/ClassAndModuleThatMergeWithModulesExportedGenericFunctionAndGenericClassStaticFunctionOfTheSameName.js
+++ b/tests/baselines/reference/ClassAndModuleThatMergeWithModulesExportedGenericFunctionAndGenericClassStaticFunctionOfTheSameName.js
@@ -22,7 +22,6 @@ var clodule = (function () {
     clodule.fn = function (id) { };
     return clodule;
 }());
-var clodule;
 (function (clodule) {
     // error: duplicate identifier expected
     function fn(x, y) {
diff --git a/tests/baselines/reference/ClassAndModuleThatMergeWithModulesExportedGenericFunctionAndNonGenericClassStaticFunctionOfTheSameName.js b/tests/baselines/reference/ClassAndModuleThatMergeWithModulesExportedGenericFunctionAndNonGenericClassStaticFunctionOfTheSameName.js
index 402e0e6ad09..6d04d636eb2 100644
--- a/tests/baselines/reference/ClassAndModuleThatMergeWithModulesExportedGenericFunctionAndNonGenericClassStaticFunctionOfTheSameName.js
+++ b/tests/baselines/reference/ClassAndModuleThatMergeWithModulesExportedGenericFunctionAndNonGenericClassStaticFunctionOfTheSameName.js
@@ -22,7 +22,6 @@ var clodule = (function () {
     clodule.fn = function (id) { };
     return clodule;
 }());
-var clodule;
 (function (clodule) {
     // error: duplicate identifier expected
     function fn(x, y) {
diff --git a/tests/baselines/reference/ClassAndModuleThatMergeWithModulesExportedStaticFunctionUsingClassPrivateStatics.js b/tests/baselines/reference/ClassAndModuleThatMergeWithModulesExportedStaticFunctionUsingClassPrivateStatics.js
index 0b6c868128e..d3ae3cb0bcf 100644
--- a/tests/baselines/reference/ClassAndModuleThatMergeWithModulesExportedStaticFunctionUsingClassPrivateStatics.js
+++ b/tests/baselines/reference/ClassAndModuleThatMergeWithModulesExportedStaticFunctionUsingClassPrivateStatics.js
@@ -22,7 +22,6 @@ var clodule = (function () {
     clodule.sfn = function (id) { return 42; };
     return clodule;
 }());
-var clodule;
 (function (clodule) {
     // error: duplicate identifier expected
     function fn(x, y) {
diff --git a/tests/baselines/reference/ClassAndModuleThatMergeWithStaticFunctionAndExportedFunctionThatShareAName.js b/tests/baselines/reference/ClassAndModuleThatMergeWithStaticFunctionAndExportedFunctionThatShareAName.js
index b8e332f1932..c6b463fa5fd 100644
--- a/tests/baselines/reference/ClassAndModuleThatMergeWithStaticFunctionAndExportedFunctionThatShareAName.js
+++ b/tests/baselines/reference/ClassAndModuleThatMergeWithStaticFunctionAndExportedFunctionThatShareAName.js
@@ -31,7 +31,6 @@ var Point = (function () {
     Point.Origin = function () { return { x: 0, y: 0 }; }; // unexpected error here bug 840246
     return Point;
 }());
-var Point;
 (function (Point) {
     function Origin() { return null; } //expected duplicate identifier error
     Point.Origin = Origin;
@@ -47,7 +46,6 @@ var A;
         return Point;
     }());
     A.Point = Point;
-    var Point;
     (function (Point) {
         function Origin() { return ""; } //expected duplicate identifier error
         Point.Origin = Origin;
diff --git a/tests/baselines/reference/ClassAndModuleThatMergeWithStaticFunctionAndNonExportedFunctionThatShareAName.js b/tests/baselines/reference/ClassAndModuleThatMergeWithStaticFunctionAndNonExportedFunctionThatShareAName.js
index 3fcbdefdf7e..7741290babc 100644
--- a/tests/baselines/reference/ClassAndModuleThatMergeWithStaticFunctionAndNonExportedFunctionThatShareAName.js
+++ b/tests/baselines/reference/ClassAndModuleThatMergeWithStaticFunctionAndNonExportedFunctionThatShareAName.js
@@ -31,7 +31,6 @@ var Point = (function () {
     Point.Origin = function () { return { x: 0, y: 0 }; };
     return Point;
 }());
-var Point;
 (function (Point) {
     function Origin() { return ""; } // not an error, since not exported
 })(Point || (Point = {}));
@@ -46,7 +45,6 @@ var A;
         return Point;
     }());
     A.Point = Point;
-    var Point;
     (function (Point) {
         function Origin() { return ""; } // not an error since not exported
     })(Point = A.Point || (A.Point = {}));
diff --git a/tests/baselines/reference/ClassAndModuleThatMergeWithStaticVariableAndExportedVarThatShareAName.js b/tests/baselines/reference/ClassAndModuleThatMergeWithStaticVariableAndExportedVarThatShareAName.js
index 63d3739846b..cb2f7c6cb77 100644
--- a/tests/baselines/reference/ClassAndModuleThatMergeWithStaticVariableAndExportedVarThatShareAName.js
+++ b/tests/baselines/reference/ClassAndModuleThatMergeWithStaticVariableAndExportedVarThatShareAName.js
@@ -31,7 +31,6 @@ var Point = (function () {
     return Point;
 }());
 Point.Origin = { x: 0, y: 0 };
-var Point;
 (function (Point) {
     Point.Origin = ""; //expected duplicate identifier error
 })(Point || (Point = {}));
@@ -46,7 +45,6 @@ var A;
     }());
     Point.Origin = { x: 0, y: 0 };
     A.Point = Point;
-    var Point;
     (function (Point) {
         Point.Origin = ""; //expected duplicate identifier error
     })(Point = A.Point || (A.Point = {}));
diff --git a/tests/baselines/reference/ClassAndModuleThatMergeWithStaticVariableAndNonExportedVarThatShareAName.js b/tests/baselines/reference/ClassAndModuleThatMergeWithStaticVariableAndNonExportedVarThatShareAName.js
index 3921546a21c..ef77d6257fb 100644
--- a/tests/baselines/reference/ClassAndModuleThatMergeWithStaticVariableAndNonExportedVarThatShareAName.js
+++ b/tests/baselines/reference/ClassAndModuleThatMergeWithStaticVariableAndNonExportedVarThatShareAName.js
@@ -31,7 +31,6 @@ var Point = (function () {
     return Point;
 }());
 Point.Origin = { x: 0, y: 0 };
-var Point;
 (function (Point) {
     var Origin = ""; // not an error, since not exported
 })(Point || (Point = {}));
@@ -46,7 +45,6 @@ var A;
     }());
     Point.Origin = { x: 0, y: 0 };
     A.Point = Point;
-    var Point;
     (function (Point) {
         var Origin = ""; // not an error since not exported
     })(Point = A.Point || (A.Point = {}));
diff --git a/tests/baselines/reference/ClassAndModuleWithSameNameAndCommonRoot.js b/tests/baselines/reference/ClassAndModuleWithSameNameAndCommonRoot.js
index 247dc4fe62d..b800ca2d24b 100644
--- a/tests/baselines/reference/ClassAndModuleWithSameNameAndCommonRoot.js
+++ b/tests/baselines/reference/ClassAndModuleWithSameNameAndCommonRoot.js
@@ -76,7 +76,6 @@ var A = (function () {
     }
     return A;
 }());
-var A;
 (function (A) {
     A.Instance = new A();
 })(A || (A = {}));
diff --git a/tests/baselines/reference/EnumAndModuleWithSameNameAndCommonRoot.js b/tests/baselines/reference/EnumAndModuleWithSameNameAndCommonRoot.js
index e6a0eb0584d..c0756a56e90 100644
--- a/tests/baselines/reference/EnumAndModuleWithSameNameAndCommonRoot.js
+++ b/tests/baselines/reference/EnumAndModuleWithSameNameAndCommonRoot.js
@@ -22,7 +22,6 @@ var enumdule;
     enumdule[enumdule["Red"] = 0] = "Red";
     enumdule[enumdule["Blue"] = 1] = "Blue";
 })(enumdule || (enumdule = {}));
-var enumdule;
 (function (enumdule) {
     var Point = (function () {
         function Point(x, y) {
diff --git a/tests/baselines/reference/FunctionAndModuleWithSameNameAndCommonRoot.js b/tests/baselines/reference/FunctionAndModuleWithSameNameAndCommonRoot.js
index 369a5b4dd52..daa56620014 100644
--- a/tests/baselines/reference/FunctionAndModuleWithSameNameAndCommonRoot.js
+++ b/tests/baselines/reference/FunctionAndModuleWithSameNameAndCommonRoot.js
@@ -72,7 +72,6 @@ var B;
         return { x: 0, y: 0 };
     }
     B.Point = Point;
-    var Point;
     (function (Point) {
         Point.Origin = { x: 0, y: 0 };
     })(Point = B.Point || (B.Point = {}));
diff --git a/tests/baselines/reference/ModuleAndEnumWithSameNameAndCommonRoot.js b/tests/baselines/reference/ModuleAndEnumWithSameNameAndCommonRoot.js
index 6928e189a07..fa38dae1298 100644
--- a/tests/baselines/reference/ModuleAndEnumWithSameNameAndCommonRoot.js
+++ b/tests/baselines/reference/ModuleAndEnumWithSameNameAndCommonRoot.js
@@ -28,7 +28,6 @@ var enumdule;
     }());
     enumdule.Point = Point;
 })(enumdule || (enumdule = {}));
-var enumdule;
 (function (enumdule) {
     enumdule[enumdule["Red"] = 0] = "Red";
     enumdule[enumdule["Blue"] = 1] = "Blue";
diff --git a/tests/baselines/reference/TwoInternalModulesThatMergeEachWithExportedAndNonExportedClassesOfTheSameName.js b/tests/baselines/reference/TwoInternalModulesThatMergeEachWithExportedAndNonExportedClassesOfTheSameName.js
index dd29b88421c..4c5ea297d27 100644
--- a/tests/baselines/reference/TwoInternalModulesThatMergeEachWithExportedAndNonExportedClassesOfTheSameName.js
+++ b/tests/baselines/reference/TwoInternalModulesThatMergeEachWithExportedAndNonExportedClassesOfTheSameName.js
@@ -50,7 +50,6 @@ var A;
     }());
     A.Point = Point;
 })(A || (A = {}));
-var A;
 (function (A) {
     var Point = (function () {
         function Point() {
@@ -79,7 +78,6 @@ var X;
         })(Z = Y.Z || (Y.Z = {}));
     })(Y = X.Y || (X.Y = {}));
 })(X || (X = {}));
-var X;
 (function (X) {
     var Y;
     (function (Y) {
diff --git a/tests/baselines/reference/TwoInternalModulesThatMergeEachWithExportedClassesOfTheSameName.js b/tests/baselines/reference/TwoInternalModulesThatMergeEachWithExportedClassesOfTheSameName.js
index 2a75b92e2db..e98ed836f7b 100644
--- a/tests/baselines/reference/TwoInternalModulesThatMergeEachWithExportedClassesOfTheSameName.js
+++ b/tests/baselines/reference/TwoInternalModulesThatMergeEachWithExportedClassesOfTheSameName.js
@@ -42,7 +42,6 @@ var A;
     }());
     A.Point = Point;
 })(A || (A = {}));
-var A;
 (function (A) {
     // expected error
     var Point = (function () {
@@ -67,7 +66,6 @@ var X;
         })(Z = Y.Z || (Y.Z = {}));
     })(Y = X.Y || (X.Y = {}));
 })(X || (X = {}));
-var X;
 (function (X) {
     var Y;
     (function (Y) {
diff --git a/tests/baselines/reference/TwoInternalModulesThatMergeEachWithExportedModulesOfTheSameName.js b/tests/baselines/reference/TwoInternalModulesThatMergeEachWithExportedModulesOfTheSameName.js
index 54ffef5a084..c8412b336dc 100644
--- a/tests/baselines/reference/TwoInternalModulesThatMergeEachWithExportedModulesOfTheSameName.js
+++ b/tests/baselines/reference/TwoInternalModulesThatMergeEachWithExportedModulesOfTheSameName.js
@@ -41,7 +41,6 @@ var A;
     (function (B) {
     })(B = A.B || (A.B = {}));
 })(A || (A = {}));
-var A;
 (function (A) {
     var B;
     (function (B) {
@@ -65,7 +64,6 @@ var X;
         })(Z = Y.Z || (Y.Z = {}));
     })(Y = X.Y || (X.Y = {}));
 })(X || (X = {}));
-var X;
 (function (X) {
     var Y;
     (function (Y) {
diff --git a/tests/baselines/reference/anyAssignabilityInInheritance.js b/tests/baselines/reference/anyAssignabilityInInheritance.js
index f73228a464b..a156abe8ab2 100644
--- a/tests/baselines/reference/anyAssignabilityInInheritance.js
+++ b/tests/baselines/reference/anyAssignabilityInInheritance.js
@@ -119,7 +119,6 @@ var E;
 })(E || (E = {}));
 var r3 = foo3(a); // any
 function f() { }
-var f;
 (function (f) {
     f.bar = 1;
 })(f || (f = {}));
@@ -129,7 +128,6 @@ var CC = (function () {
     }
     return CC;
 }());
-var CC;
 (function (CC) {
     CC.bar = 1;
 })(CC || (CC = {}));
diff --git a/tests/baselines/reference/anyAssignableToEveryType2.js b/tests/baselines/reference/anyAssignableToEveryType2.js
index c5fefb60042..9a4534296a4 100644
--- a/tests/baselines/reference/anyAssignableToEveryType2.js
+++ b/tests/baselines/reference/anyAssignableToEveryType2.js
@@ -147,7 +147,6 @@ var E;
     E[E["A"] = 0] = "A";
 })(E || (E = {}));
 function f() { }
-var f;
 (function (f) {
     f.bar = 1;
 })(f || (f = {}));
@@ -156,7 +155,6 @@ var c = (function () {
     }
     return c;
 }());
-var c;
 (function (c) {
     c.bar = 1;
 })(c || (c = {}));
diff --git a/tests/baselines/reference/assignmentCompatWithObjectMembersAccessibility.js b/tests/baselines/reference/assignmentCompatWithObjectMembersAccessibility.js
index e876ba575be..997c5f7a0c9 100644
--- a/tests/baselines/reference/assignmentCompatWithObjectMembersAccessibility.js
+++ b/tests/baselines/reference/assignmentCompatWithObjectMembersAccessibility.js
@@ -157,7 +157,6 @@ var TargetIsPublic;
     e = d; // errror
     e = e;
 })(TargetIsPublic || (TargetIsPublic = {}));
-var TargetIsPublic;
 (function (TargetIsPublic) {
     // targets
     var Base = (function () {
diff --git a/tests/baselines/reference/assignmentToObjectAndFunction.js b/tests/baselines/reference/assignmentToObjectAndFunction.js
index a3c4785b18b..d60e2de4a5a 100644
--- a/tests/baselines/reference/assignmentToObjectAndFunction.js
+++ b/tests/baselines/reference/assignmentToObjectAndFunction.js
@@ -38,20 +38,17 @@ var goodObj = {
 }; // Ok, because toString is a subtype of Object's toString
 var errFun = {}; // Error for no call signature
 function foo() { }
-var foo;
 (function (foo) {
     foo.boom = 0;
 })(foo || (foo = {}));
 var goodFundule = foo; // ok
 function bar() { }
-var bar;
 (function (bar) {
     function apply(thisArg, argArray) { }
     bar.apply = apply;
 })(bar || (bar = {}));
 var goodFundule2 = bar; // ok
 function bad() { }
-var bad;
 (function (bad) {
     bad.apply = 0;
 })(bad || (bad = {}));
diff --git a/tests/baselines/reference/augmentExportEquals3.js b/tests/baselines/reference/augmentExportEquals3.js
index 82cfa5f2166..94cb0f8ce95 100644
--- a/tests/baselines/reference/augmentExportEquals3.js
+++ b/tests/baselines/reference/augmentExportEquals3.js
@@ -28,7 +28,6 @@ let b = x.b;
 define(["require", "exports"], function (require, exports) {
     "use strict";
     function foo() { }
-    var foo;
     (function (foo) {
         foo.v = 1;
     })(foo || (foo = {}));
diff --git a/tests/baselines/reference/augmentExportEquals4.js b/tests/baselines/reference/augmentExportEquals4.js
index ee0fc1892c2..ff0cbd44e0b 100644
--- a/tests/baselines/reference/augmentExportEquals4.js
+++ b/tests/baselines/reference/augmentExportEquals4.js
@@ -32,7 +32,6 @@ define(["require", "exports"], function (require, exports) {
         }
         return foo;
     }());
-    var foo;
     (function (foo) {
         foo.v = 1;
     })(foo || (foo = {}));
diff --git a/tests/baselines/reference/augmentExportEquals6.js b/tests/baselines/reference/augmentExportEquals6.js
index 94dfa389c6d..3f9cbbb0af8 100644
--- a/tests/baselines/reference/augmentExportEquals6.js
+++ b/tests/baselines/reference/augmentExportEquals6.js
@@ -36,7 +36,6 @@ define(["require", "exports"], function (require, exports) {
         }
         return foo;
     }());
-    var foo;
     (function (foo) {
         var A = (function () {
             function A() {
diff --git a/tests/baselines/reference/augmentedTypesClass.js b/tests/baselines/reference/augmentedTypesClass.js
index 48cc4ef05de..b9c263971b3 100644
--- a/tests/baselines/reference/augmentedTypesClass.js
+++ b/tests/baselines/reference/augmentedTypesClass.js
@@ -23,7 +23,6 @@ var c4 = (function () {
     c4.prototype.foo = function () { };
     return c4;
 }());
-var c4;
 (function (c4) {
     c4[c4["One"] = 0] = "One";
 })(c4 || (c4 = {})); // error
diff --git a/tests/baselines/reference/augmentedTypesClass2.js b/tests/baselines/reference/augmentedTypesClass2.js
index ee87a2396ad..0896a03a925 100644
--- a/tests/baselines/reference/augmentedTypesClass2.js
+++ b/tests/baselines/reference/augmentedTypesClass2.js
@@ -51,7 +51,6 @@ var c33 = (function () {
     };
     return c33;
 }());
-var c33;
 (function (c33) {
     c33[c33["One"] = 0] = "One";
 })(c33 || (c33 = {}));
diff --git a/tests/baselines/reference/augmentedTypesClass3.js b/tests/baselines/reference/augmentedTypesClass3.js
index 216cd118ee6..3a4877707c6 100644
--- a/tests/baselines/reference/augmentedTypesClass3.js
+++ b/tests/baselines/reference/augmentedTypesClass3.js
@@ -27,7 +27,6 @@ var c5a = (function () {
     c5a.prototype.foo = function () { };
     return c5a;
 }());
-var c5a;
 (function (c5a) {
     var y = 2;
 })(c5a || (c5a = {})); // should be ok
@@ -37,7 +36,6 @@ var c5b = (function () {
     c5b.prototype.foo = function () { };
     return c5b;
 }());
-var c5b;
 (function (c5b) {
     c5b.y = 2;
 })(c5b || (c5b = {})); // should be ok
diff --git a/tests/baselines/reference/augmentedTypesEnum.js b/tests/baselines/reference/augmentedTypesEnum.js
index 3d2bb0b7d25..406c1a3bf69 100644
--- a/tests/baselines/reference/augmentedTypesEnum.js
+++ b/tests/baselines/reference/augmentedTypesEnum.js
@@ -69,7 +69,6 @@ var e5;
 (function (e5) {
     e5[e5["One"] = 0] = "One";
 })(e5 || (e5 = {}));
-var e5;
 (function (e5) {
     e5[e5["Two"] = 0] = "Two";
 })(e5 || (e5 = {})); // error
@@ -77,7 +76,6 @@ var e5a;
 (function (e5a) {
     e5a[e5a["One"] = 0] = "One";
 })(e5a || (e5a = {})); // error
-var e5a;
 (function (e5a) {
     e5a[e5a["One"] = 0] = "One";
 })(e5a || (e5a = {})); // error
@@ -90,7 +88,6 @@ var e6a;
 (function (e6a) {
     e6a[e6a["One"] = 0] = "One";
 })(e6a || (e6a = {}));
-var e6a;
 (function (e6a) {
     var y = 2;
 })(e6a || (e6a = {})); // should be error
@@ -98,7 +95,6 @@ var e6b;
 (function (e6b) {
     e6b[e6b["One"] = 0] = "One";
 })(e6b || (e6b = {}));
-var e6b;
 (function (e6b) {
     e6b.y = 2;
 })(e6b || (e6b = {})); // should be error
diff --git a/tests/baselines/reference/augmentedTypesEnum3.js b/tests/baselines/reference/augmentedTypesEnum3.js
index e0d8b51cf72..4df9dada530 100644
--- a/tests/baselines/reference/augmentedTypesEnum3.js
+++ b/tests/baselines/reference/augmentedTypesEnum3.js
@@ -25,13 +25,11 @@ var E;
 (function (E) {
     var t;
 })(E || (E = {}));
-var E;
 (function (E) {
 })(E || (E = {}));
 var F;
 (function (F) {
 })(F || (F = {}));
-var F;
 (function (F) {
     var t;
 })(F || (F = {}));
@@ -39,15 +37,12 @@ var A;
 (function (A) {
     var o;
 })(A || (A = {}));
-var A;
 (function (A) {
     A[A["b"] = 0] = "b";
 })(A || (A = {}));
-var A;
 (function (A) {
     A[A["c"] = 0] = "c";
 })(A || (A = {}));
-var A;
 (function (A) {
     var p;
 })(A || (A = {}));
diff --git a/tests/baselines/reference/augmentedTypesFunction.js b/tests/baselines/reference/augmentedTypesFunction.js
index 72f36aeeccc..95f91a938d7 100644
--- a/tests/baselines/reference/augmentedTypesFunction.js
+++ b/tests/baselines/reference/augmentedTypesFunction.js
@@ -63,19 +63,16 @@ var y3a = (function () {
 }()); // error
 // function then enum
 function y4() { } // error
-var y4;
 (function (y4) {
     y4[y4["One"] = 0] = "One";
 })(y4 || (y4 = {})); // error
 // function then internal module
 function y5() { }
 function y5a() { }
-var y5a;
 (function (y5a) {
     var y = 2;
 })(y5a || (y5a = {})); // should be an error
 function y5b() { }
-var y5b;
 (function (y5b) {
     y5b.y = 3;
 })(y5b || (y5b = {})); // should be an error
diff --git a/tests/baselines/reference/augmentedTypesModules.js b/tests/baselines/reference/augmentedTypesModules.js
index 39a4c17454b..61dd64174d9 100644
--- a/tests/baselines/reference/augmentedTypesModules.js
+++ b/tests/baselines/reference/augmentedTypesModules.js
@@ -138,7 +138,6 @@ function m2b() { }
 // should be errors to have function first
 function m2c() { }
 ;
-var m2c;
 (function (m2c) {
     m2c.y = 2;
 })(m2c || (m2c = {}));
@@ -146,7 +145,6 @@ function m2f() { }
 ;
 function m2g() { }
 ;
-var m2g;
 (function (m2g) {
     var C = (function () {
         function C() {
@@ -177,7 +175,6 @@ var m3b = (function () {
     m3b.prototype.foo = function () { };
     return m3b;
 }());
-var m3b;
 (function (m3b) {
     var y = 2;
 })(m3b || (m3b = {}));
@@ -187,7 +184,6 @@ var m3c = (function () {
     m3c.prototype.foo = function () { };
     return m3c;
 }());
-var m3c;
 (function (m3c) {
     m3c.y = 2;
 })(m3c || (m3c = {}));
@@ -216,7 +212,6 @@ var m4a;
 (function (m4a) {
     var y = 2;
 })(m4a || (m4a = {}));
-var m4a;
 (function (m4a) {
     m4a[m4a["One"] = 0] = "One";
 })(m4a || (m4a = {}));
@@ -224,7 +219,6 @@ var m4b;
 (function (m4b) {
     m4b.y = 2;
 })(m4b || (m4b = {}));
-var m4b;
 (function (m4b) {
     m4b[m4b["One"] = 0] = "One";
 })(m4b || (m4b = {}));
@@ -241,7 +235,6 @@ var m4d;
         return C;
     }());
 })(m4d || (m4d = {}));
-var m4d;
 (function (m4d) {
     m4d[m4d["One"] = 0] = "One";
 })(m4d || (m4d = {}));
diff --git a/tests/baselines/reference/augmentedTypesModules2.js b/tests/baselines/reference/augmentedTypesModules2.js
index 82bba357bba..9f7d3613d57 100644
--- a/tests/baselines/reference/augmentedTypesModules2.js
+++ b/tests/baselines/reference/augmentedTypesModules2.js
@@ -45,7 +45,6 @@ function m2b() { }
 ; // error since the module is instantiated
 function m2c() { }
 ;
-var m2c;
 (function (m2c) {
     m2c.y = 2;
 })(m2c || (m2c = {}));
@@ -59,7 +58,6 @@ function m2f() { }
 ;
 function m2g() { }
 ;
-var m2g;
 (function (m2g) {
     var C = (function () {
         function C() {
diff --git a/tests/baselines/reference/augmentedTypesModules3b.js b/tests/baselines/reference/augmentedTypesModules3b.js
index a422ad79973..02da7b41f2e 100644
--- a/tests/baselines/reference/augmentedTypesModules3b.js
+++ b/tests/baselines/reference/augmentedTypesModules3b.js
@@ -25,7 +25,6 @@ var m3b = (function () {
     m3b.prototype.foo = function () { };
     return m3b;
 }());
-var m3b;
 (function (m3b) {
     var y = 2;
 })(m3b || (m3b = {}));
@@ -35,7 +34,6 @@ var m3c = (function () {
     m3c.prototype.foo = function () { };
     return m3c;
 }());
-var m3c;
 (function (m3c) {
     m3c.y = 2;
 })(m3c || (m3c = {}));
diff --git a/tests/baselines/reference/augmentedTypesModules4.js b/tests/baselines/reference/augmentedTypesModules4.js
index ed86c057462..5db6c42d707 100644
--- a/tests/baselines/reference/augmentedTypesModules4.js
+++ b/tests/baselines/reference/augmentedTypesModules4.js
@@ -30,7 +30,6 @@ var m4a;
 (function (m4a) {
     var y = 2;
 })(m4a || (m4a = {}));
-var m4a;
 (function (m4a) {
     m4a[m4a["One"] = 0] = "One";
 })(m4a || (m4a = {}));
@@ -38,7 +37,6 @@ var m4b;
 (function (m4b) {
     m4b.y = 2;
 })(m4b || (m4b = {}));
-var m4b;
 (function (m4b) {
     m4b[m4b["One"] = 0] = "One";
 })(m4b || (m4b = {}));
@@ -55,7 +53,6 @@ var m4d;
         return C;
     }());
 })(m4d || (m4d = {}));
-var m4d;
 (function (m4d) {
     m4d[m4d["One"] = 0] = "One";
 })(m4d || (m4d = {}));
diff --git a/tests/baselines/reference/autonumberingInEnums.js b/tests/baselines/reference/autonumberingInEnums.js
index e6bf29bda8f..218b10ae44c 100644
--- a/tests/baselines/reference/autonumberingInEnums.js
+++ b/tests/baselines/reference/autonumberingInEnums.js
@@ -12,7 +12,6 @@ var Foo;
 (function (Foo) {
     Foo[Foo["a"] = 1] = "a";
 })(Foo || (Foo = {}));
-var Foo;
 (function (Foo) {
     Foo[Foo["b"] = 0] = "b"; // should work fine
 })(Foo || (Foo = {}));
diff --git a/tests/baselines/reference/callSignatureWithoutReturnTypeAnnotationInference.js b/tests/baselines/reference/callSignatureWithoutReturnTypeAnnotationInference.js
index baa7f6c2c95..caba9d7ef6e 100644
--- a/tests/baselines/reference/callSignatureWithoutReturnTypeAnnotationInference.js
+++ b/tests/baselines/reference/callSignatureWithoutReturnTypeAnnotationInference.js
@@ -204,7 +204,6 @@ function foo12() {
 }
 var r12 = foo12();
 function m1() { return 1; }
-var m1;
 (function (m1) {
     m1.y = 2;
 })(m1 || (m1 = {}));
@@ -217,7 +216,6 @@ var c1 = (function () {
     }
     return c1;
 }());
-var c1;
 (function (c1) {
     c1.x = 1;
 })(c1 || (c1 = {}));
@@ -229,7 +227,6 @@ var e1;
 (function (e1) {
     e1[e1["A"] = 0] = "A";
 })(e1 || (e1 = {}));
-var e1;
 (function (e1) {
     e1.y = 1;
 })(e1 || (e1 = {}));
diff --git a/tests/baselines/reference/circularTypeofWithFunctionModule.js b/tests/baselines/reference/circularTypeofWithFunctionModule.js
index 6ce1dd62fc5..428efa6f45b 100644
--- a/tests/baselines/reference/circularTypeofWithFunctionModule.js
+++ b/tests/baselines/reference/circularTypeofWithFunctionModule.js
@@ -27,7 +27,6 @@ var Foo = (function () {
 function maker(value) {
     return maker.Bar;
 }
-var maker;
 (function (maker) {
     var Bar = (function (_super) {
         __extends(Bar, _super);
diff --git a/tests/baselines/reference/classDeclarationMergedInModuleWithContinuation.js b/tests/baselines/reference/classDeclarationMergedInModuleWithContinuation.js
index 7ab6cb2ceca..6969f212bca 100644
--- a/tests/baselines/reference/classDeclarationMergedInModuleWithContinuation.js
+++ b/tests/baselines/reference/classDeclarationMergedInModuleWithContinuation.js
@@ -25,12 +25,10 @@ var M;
         return N;
     }());
     M.N = N;
-    var N;
     (function (N) {
         N.v = 0;
     })(N = M.N || (M.N = {}));
 })(M || (M = {}));
-var M;
 (function (M) {
     var O = (function (_super) {
         __extends(O, _super);
diff --git a/tests/baselines/reference/classExtendsClauseClassMergedWithModuleNotReferingConstructor.js b/tests/baselines/reference/classExtendsClauseClassMergedWithModuleNotReferingConstructor.js
index 80b4b7c175d..4247bb96bae 100644
--- a/tests/baselines/reference/classExtendsClauseClassMergedWithModuleNotReferingConstructor.js
+++ b/tests/baselines/reference/classExtendsClauseClassMergedWithModuleNotReferingConstructor.js
@@ -24,7 +24,6 @@ var A = (function () {
     }
     return A;
 }());
-var A;
 (function (A) {
 })(A || (A = {}));
 var Foo;
diff --git a/tests/baselines/reference/cloduleAcrossModuleDefinitions.js b/tests/baselines/reference/cloduleAcrossModuleDefinitions.js
index f0f31325aed..ac3ff22852f 100644
--- a/tests/baselines/reference/cloduleAcrossModuleDefinitions.js
+++ b/tests/baselines/reference/cloduleAcrossModuleDefinitions.js
@@ -27,7 +27,6 @@ var A;
     }());
     A.B = B;
 })(A || (A = {}));
-var A;
 (function (A) {
     var B;
     (function (B) {
diff --git a/tests/baselines/reference/cloduleAndTypeParameters.js b/tests/baselines/reference/cloduleAndTypeParameters.js
index 2d47ce1ef75..c37ec8d584f 100644
--- a/tests/baselines/reference/cloduleAndTypeParameters.js
+++ b/tests/baselines/reference/cloduleAndTypeParameters.js
@@ -19,7 +19,6 @@ var Foo = (function () {
     }
     return Foo;
 }());
-var Foo;
 (function (Foo) {
     var Baz = (function () {
         function Baz() {
diff --git a/tests/baselines/reference/cloduleStaticMembers.js b/tests/baselines/reference/cloduleStaticMembers.js
index 868b9305bdf..b696a842f3b 100644
--- a/tests/baselines/reference/cloduleStaticMembers.js
+++ b/tests/baselines/reference/cloduleStaticMembers.js
@@ -20,7 +20,6 @@ var Clod = (function () {
 }());
 Clod.x = 10;
 Clod.y = 10;
-var Clod;
 (function (Clod) {
     var p = Clod.x;
     var q = x;
diff --git a/tests/baselines/reference/cloduleWithDuplicateMember1.js b/tests/baselines/reference/cloduleWithDuplicateMember1.js
index 6f4a2809b8e..d364af3a751 100644
--- a/tests/baselines/reference/cloduleWithDuplicateMember1.js
+++ b/tests/baselines/reference/cloduleWithDuplicateMember1.js
@@ -34,11 +34,9 @@ var C = (function () {
     C.foo = function () { };
     return C;
 }());
-var C;
 (function (C) {
     C.x = 1;
 })(C || (C = {}));
-var C;
 (function (C) {
     function foo() { }
     C.foo = foo;
diff --git a/tests/baselines/reference/cloduleWithDuplicateMember2.js b/tests/baselines/reference/cloduleWithDuplicateMember2.js
index f0e8af0e3d2..927ec4356b5 100644
--- a/tests/baselines/reference/cloduleWithDuplicateMember2.js
+++ b/tests/baselines/reference/cloduleWithDuplicateMember2.js
@@ -27,11 +27,9 @@ var C = (function () {
     });
     return C;
 }());
-var C;
 (function (C) {
     C.x = 1;
 })(C || (C = {}));
-var C;
 (function (C) {
     function x() { }
     C.x = x;
diff --git a/tests/baselines/reference/cloduleWithPriorInstantiatedModule.js b/tests/baselines/reference/cloduleWithPriorInstantiatedModule.js
index 00040923627..e6bb334a424 100644
--- a/tests/baselines/reference/cloduleWithPriorInstantiatedModule.js
+++ b/tests/baselines/reference/cloduleWithPriorInstantiatedModule.js
@@ -28,7 +28,6 @@ var Moclodule = (function () {
     return Moclodule;
 }());
 // Instantiated module.
-var Moclodule;
 (function (Moclodule) {
     var Manager = (function () {
         function Manager() {
diff --git a/tests/baselines/reference/cloduleWithPriorUninstantiatedModule.js b/tests/baselines/reference/cloduleWithPriorUninstantiatedModule.js
index ba29858c5dd..552f9a57656 100644
--- a/tests/baselines/reference/cloduleWithPriorUninstantiatedModule.js
+++ b/tests/baselines/reference/cloduleWithPriorUninstantiatedModule.js
@@ -22,7 +22,6 @@ var Moclodule = (function () {
     return Moclodule;
 }());
 // Instantiated module.
-var Moclodule;
 (function (Moclodule) {
     var Manager = (function () {
         function Manager() {
diff --git a/tests/baselines/reference/cloduleWithRecursiveReference.js b/tests/baselines/reference/cloduleWithRecursiveReference.js
index d07af909cc7..6da2de4c07e 100644
--- a/tests/baselines/reference/cloduleWithRecursiveReference.js
+++ b/tests/baselines/reference/cloduleWithRecursiveReference.js
@@ -16,7 +16,6 @@ var M;
         return C;
     }());
     M.C = C;
-    var C;
     (function (C_1) {
         C_1.C = M.C;
     })(C = M.C || (M.C = {}));
diff --git a/tests/baselines/reference/clodulesDerivedClasses.js b/tests/baselines/reference/clodulesDerivedClasses.js
index 7e6f26ad591..6f8a56786a6 100644
--- a/tests/baselines/reference/clodulesDerivedClasses.js
+++ b/tests/baselines/reference/clodulesDerivedClasses.js
@@ -33,7 +33,6 @@ var Shape = (function () {
     }
     return Shape;
 }());
-var Shape;
 (function (Shape) {
     var Utils;
     (function (Utils) {
@@ -48,7 +47,6 @@ var Path = (function (_super) {
     }
     return Path;
 }(Shape));
-var Path;
 (function (Path) {
     var Utils;
     (function (Utils) {
diff --git a/tests/baselines/reference/collisionCodeGenModuleWithAccessorChildren.js b/tests/baselines/reference/collisionCodeGenModuleWithAccessorChildren.js
index fd502b32ccf..977d0c4bf49 100644
--- a/tests/baselines/reference/collisionCodeGenModuleWithAccessorChildren.js
+++ b/tests/baselines/reference/collisionCodeGenModuleWithAccessorChildren.js
@@ -62,7 +62,6 @@ var M;
         return c;
     }());
 })(M || (M = {}));
-var M;
 (function (M_2) {
     var d = (function () {
         function d() {
@@ -78,7 +77,6 @@ var M;
         return d;
     }());
 })(M || (M = {}));
-var M;
 (function (M) {
     var e = (function () {
         function e() {
@@ -93,7 +91,6 @@ var M;
         return e;
     }());
 })(M || (M = {}));
-var M;
 (function (M_3) {
     var f = (function () {
         function f() {
@@ -109,7 +106,6 @@ var M;
         return f;
     }());
 })(M || (M = {}));
-var M;
 (function (M) {
     var e = (function () {
         function e() {
diff --git a/tests/baselines/reference/collisionCodeGenModuleWithConstructorChildren.js b/tests/baselines/reference/collisionCodeGenModuleWithConstructorChildren.js
index 24332a84797..5dd1fb96e1d 100644
--- a/tests/baselines/reference/collisionCodeGenModuleWithConstructorChildren.js
+++ b/tests/baselines/reference/collisionCodeGenModuleWithConstructorChildren.js
@@ -34,7 +34,6 @@ var M;
         return c;
     }());
 })(M || (M = {}));
-var M;
 (function (M_2) {
     var d = (function () {
         function d(M, p) {
@@ -44,7 +43,6 @@ var M;
         return d;
     }());
 })(M || (M = {}));
-var M;
 (function (M_3) {
     var d2 = (function () {
         function d2() {
diff --git a/tests/baselines/reference/collisionCodeGenModuleWithFunctionChildren.js b/tests/baselines/reference/collisionCodeGenModuleWithFunctionChildren.js
index 252ad2c63dc..afe3cb43f28 100644
--- a/tests/baselines/reference/collisionCodeGenModuleWithFunctionChildren.js
+++ b/tests/baselines/reference/collisionCodeGenModuleWithFunctionChildren.js
@@ -27,14 +27,12 @@ var M;
         if (p === void 0) { p = M_1.x; }
     }
 })(M || (M = {}));
-var M;
 (function (M_2) {
     function fn2() {
         var M;
         var p = M_2.x;
     }
 })(M || (M = {}));
-var M;
 (function (M_3) {
     function fn3() {
         function M() {
diff --git a/tests/baselines/reference/collisionCodeGenModuleWithMethodChildren.js b/tests/baselines/reference/collisionCodeGenModuleWithMethodChildren.js
index a42b6502483..4ff4cb22668 100644
--- a/tests/baselines/reference/collisionCodeGenModuleWithMethodChildren.js
+++ b/tests/baselines/reference/collisionCodeGenModuleWithMethodChildren.js
@@ -45,7 +45,6 @@ var M;
         return c;
     }());
 })(M || (M = {}));
-var M;
 (function (M_2) {
     var d = (function () {
         function d() {
@@ -57,7 +56,6 @@ var M;
         return d;
     }());
 })(M || (M = {}));
-var M;
 (function (M_3) {
     var e = (function () {
         function e() {
@@ -70,7 +68,6 @@ var M;
         return e;
     }());
 })(M || (M = {}));
-var M;
 (function (M) {
     var f = (function () {
         function f() {
diff --git a/tests/baselines/reference/collisionCodeGenModuleWithModuleChildren.js b/tests/baselines/reference/collisionCodeGenModuleWithModuleChildren.js
index 6726d32d77d..a4486c48de3 100644
--- a/tests/baselines/reference/collisionCodeGenModuleWithModuleChildren.js
+++ b/tests/baselines/reference/collisionCodeGenModuleWithModuleChildren.js
@@ -52,7 +52,6 @@ var M;
         var p = M_1.x;
     })(m1 || (m1 = {}));
 })(M || (M = {}));
-var M;
 (function (M_2) {
     var m2;
     (function (m2) {
@@ -65,7 +64,6 @@ var M;
         var p2 = new M();
     })(m2 || (m2 = {}));
 })(M || (M = {}));
-var M;
 (function (M_3) {
     var m3;
     (function (m3) {
@@ -75,7 +73,6 @@ var M;
         var p2 = M();
     })(m3 || (m3 = {}));
 })(M || (M = {}));
-var M;
 (function (M) {
     var m3;
     (function (m3) {
@@ -83,7 +80,6 @@ var M;
         var p2;
     })(m3 || (m3 = {}));
 })(M || (M = {}));
-var M;
 (function (M_4) {
     var m4;
     (function (m4) {
diff --git a/tests/baselines/reference/collisionCodeGenModuleWithModuleReopening.js b/tests/baselines/reference/collisionCodeGenModuleWithModuleReopening.js
index eed1095cdc3..def2c8c2bb0 100644
--- a/tests/baselines/reference/collisionCodeGenModuleWithModuleReopening.js
+++ b/tests/baselines/reference/collisionCodeGenModuleWithModuleReopening.js
@@ -40,7 +40,6 @@ var m1;
     m1_1.m1 = m1;
 })(m1 || (m1 = {}));
 var foo = new m1.m1();
-var m1;
 (function (m1) {
     var c1 = (function () {
         function c1() {
@@ -64,7 +63,6 @@ var m2;
     var x = new c1();
 })(m2 || (m2 = {}));
 var foo3 = new m2.c1();
-var m2;
 (function (m2_1) {
     var m2 = (function () {
         function m2() {
diff --git a/tests/baselines/reference/commentsMultiModuleMultiFile.js b/tests/baselines/reference/commentsMultiModuleMultiFile.js
index 5b30279def5..67794577226 100644
--- a/tests/baselines/reference/commentsMultiModuleMultiFile.js
+++ b/tests/baselines/reference/commentsMultiModuleMultiFile.js
@@ -51,7 +51,6 @@ define(["require", "exports"], function (require, exports) {
         multiM.b = b;
     })(multiM = exports.multiM || (exports.multiM = {}));
     /** thi is multi module 2*/
-    var multiM;
     (function (multiM) {
         /** class c comment*/
         var c = (function () {
diff --git a/tests/baselines/reference/commentsMultiModuleSingleFile.js b/tests/baselines/reference/commentsMultiModuleSingleFile.js
index 63b6c67888b..0e00a3eaff6 100644
--- a/tests/baselines/reference/commentsMultiModuleSingleFile.js
+++ b/tests/baselines/reference/commentsMultiModuleSingleFile.js
@@ -44,7 +44,6 @@ var multiM;
     multiM.d = d;
 })(multiM || (multiM = {}));
 /// this is multi module 2
-var multiM;
 (function (multiM) {
     /** class c comment*/
     var c = (function () {
diff --git a/tests/baselines/reference/constructSignaturesWithOverloads2.js b/tests/baselines/reference/constructSignaturesWithOverloads2.js
index eae1b358dcc..b82c6d00a4b 100644
--- a/tests/baselines/reference/constructSignaturesWithOverloads2.js
+++ b/tests/baselines/reference/constructSignaturesWithOverloads2.js
@@ -47,7 +47,6 @@ var C = (function () {
     }
     return C;
 }());
-var C;
 (function (C) {
     C.x = 1;
 })(C || (C = {}));
@@ -57,7 +56,6 @@ var C2 = (function () {
     }
     return C2;
 }());
-var C2;
 (function (C2) {
     C2.x = 1;
 })(C2 || (C2 = {}));
diff --git a/tests/baselines/reference/declFileGenericType2.js b/tests/baselines/reference/declFileGenericType2.js
index a4636d82993..df3abafa568 100644
--- a/tests/baselines/reference/declFileGenericType2.js
+++ b/tests/baselines/reference/declFileGenericType2.js
@@ -67,7 +67,6 @@ var templa;
     })(dom = templa.dom || (templa.dom = {}));
 })(templa || (templa = {}));
 // Module
-var templa;
 (function (templa) {
     var dom;
     (function (dom) {
diff --git a/tests/baselines/reference/declFileTypeAnnotationTypeAlias.js b/tests/baselines/reference/declFileTypeAnnotationTypeAlias.js
index f7672149308..171625efe1a 100644
--- a/tests/baselines/reference/declFileTypeAnnotationTypeAlias.js
+++ b/tests/baselines/reference/declFileTypeAnnotationTypeAlias.js
@@ -50,7 +50,6 @@ var M;
         m.c = c;
     })(m = M.m || (M.m = {}));
 })(M || (M = {}));
-var M;
 (function (M) {
     var N;
     (function (N) {
diff --git a/tests/baselines/reference/declFileWithClassNameConflictingWithClassReferredByExtendsClause.js b/tests/baselines/reference/declFileWithClassNameConflictingWithClassReferredByExtendsClause.js
index 4ac08f97a52..b705e80ad82 100644
--- a/tests/baselines/reference/declFileWithClassNameConflictingWithClassReferredByExtendsClause.js
+++ b/tests/baselines/reference/declFileWithClassNameConflictingWithClassReferredByExtendsClause.js
@@ -43,7 +43,6 @@ var X;
         })(base = Y.base || (Y.base = {}));
     })(Y = X.Y || (X.Y = {}));
 })(X || (X = {}));
-var X;
 (function (X) {
     var Y;
     (function (Y) {
diff --git a/tests/baselines/reference/declFileWithExtendsClauseThatHasItsContainerNameConflict.js b/tests/baselines/reference/declFileWithExtendsClauseThatHasItsContainerNameConflict.js
index 6dfce6e8e63..99684a731e6 100644
--- a/tests/baselines/reference/declFileWithExtendsClauseThatHasItsContainerNameConflict.js
+++ b/tests/baselines/reference/declFileWithExtendsClauseThatHasItsContainerNameConflict.js
@@ -36,7 +36,6 @@ var A;
         B.EventManager = EventManager;
     })(B = A.B || (A.B = {}));
 })(A || (A = {}));
-var A;
 (function (A) {
     var B;
     (function (B) {
diff --git a/tests/baselines/reference/declarationEmitNameConflicts.js b/tests/baselines/reference/declarationEmitNameConflicts.js
index 2ce92501409..6d848b42869 100644
--- a/tests/baselines/reference/declarationEmitNameConflicts.js
+++ b/tests/baselines/reference/declarationEmitNameConflicts.js
@@ -85,7 +85,6 @@ var M;
     M.c = N;
     M.d = im;
 })(M = exports.M || (exports.M = {}));
-var M;
 (function (M) {
     var P;
     (function (P) {
@@ -111,7 +110,6 @@ var M;
         P.d = M.d; // emitted incorrectly as typeof im
     })(P = M.P || (M.P = {}));
 })(M = exports.M || (exports.M = {}));
-var M;
 (function (M) {
     var Q;
     (function (Q) {
diff --git a/tests/baselines/reference/declarationEmitNameConflicts2.js b/tests/baselines/reference/declarationEmitNameConflicts2.js
index b7b345979d7..41dcec4690f 100644
--- a/tests/baselines/reference/declarationEmitNameConflicts2.js
+++ b/tests/baselines/reference/declarationEmitNameConflicts2.js
@@ -39,7 +39,6 @@ var X;
         })(base = Y.base || (Y.base = {}));
     })(Y = X.Y || (X.Y = {}));
 })(X || (X = {}));
-var X;
 (function (X) {
     var Y;
     (function (Y) {
diff --git a/tests/baselines/reference/declarationEmitNameConflicts3.js b/tests/baselines/reference/declarationEmitNameConflicts3.js
index e9d5ea3b98e..8de521a5fde 100644
--- a/tests/baselines/reference/declarationEmitNameConflicts3.js
+++ b/tests/baselines/reference/declarationEmitNameConflicts3.js
@@ -50,7 +50,6 @@ var M;
         E.f = f;
     })(E = M.E || (M.E = {}));
 })(M || (M = {}));
-var M;
 (function (M) {
     var P;
     (function (P) {
diff --git a/tests/baselines/reference/dottedModuleName.js b/tests/baselines/reference/dottedModuleName.js
index 6a8f33ca7bb..32d98676d6c 100644
--- a/tests/baselines/reference/dottedModuleName.js
+++ b/tests/baselines/reference/dottedModuleName.js
@@ -37,7 +37,6 @@ var M;
         })(X = N.X || (N.X = {}));
     })(N = M.N || (M.N = {}));
 })(M || (M = {}));
-var M;
 (function (M) {
     var N;
     (function (N) {
diff --git a/tests/baselines/reference/dottedModuleName2.js b/tests/baselines/reference/dottedModuleName2.js
index 4cbffa0e12f..33c3f459f74 100644
--- a/tests/baselines/reference/dottedModuleName2.js
+++ b/tests/baselines/reference/dottedModuleName2.js
@@ -60,7 +60,6 @@ var AA;
 })(AA || (AA = {}));
 var tmpOK = AA.B.x;
 var tmpError = A.B.x;
-var A;
 (function (A) {
     var B;
     (function (B) {
diff --git a/tests/baselines/reference/duplicateAnonymousInners1.js b/tests/baselines/reference/duplicateAnonymousInners1.js
index 24f79566d56..8cf1dc89a45 100644
--- a/tests/baselines/reference/duplicateAnonymousInners1.js
+++ b/tests/baselines/reference/duplicateAnonymousInners1.js
@@ -41,7 +41,6 @@ var Foo;
     // Inner should show up in intellisense
     Foo.Outer = 0;
 })(Foo || (Foo = {}));
-var Foo;
 (function (Foo) {
     // Should not be an error
     var Helper = (function () {
diff --git a/tests/baselines/reference/duplicateAnonymousModuleClasses.js b/tests/baselines/reference/duplicateAnonymousModuleClasses.js
index 74f80a65d40..e27d6987e80 100644
--- a/tests/baselines/reference/duplicateAnonymousModuleClasses.js
+++ b/tests/baselines/reference/duplicateAnonymousModuleClasses.js
@@ -65,7 +65,6 @@ var F;
         return Helper;
     }());
 })(F || (F = {}));
-var F;
 (function (F) {
     // Should not be an error
     var Helper = (function () {
@@ -82,7 +81,6 @@ var Foo;
         return Helper;
     }());
 })(Foo || (Foo = {}));
-var Foo;
 (function (Foo) {
     // Should not be an error
     var Helper = (function () {
@@ -101,7 +99,6 @@ var Gar;
             return Helper;
         }());
     })(Foo || (Foo = {}));
-    var Foo;
     (function (Foo) {
         // Should not be an error
         var Helper = (function () {
diff --git a/tests/baselines/reference/duplicateIdentifiersAcrossContainerBoundaries.js b/tests/baselines/reference/duplicateIdentifiersAcrossContainerBoundaries.js
index eae9e9e4de1..37fb4fcb633 100644
--- a/tests/baselines/reference/duplicateIdentifiersAcrossContainerBoundaries.js
+++ b/tests/baselines/reference/duplicateIdentifiersAcrossContainerBoundaries.js
@@ -62,12 +62,10 @@ var M;
     }());
     M.I = I;
 })(M || (M = {}));
-var M;
 (function (M) {
     function f() { }
     M.f = f;
 })(M || (M = {}));
-var M;
 (function (M) {
     var f = (function () {
         function f() {
@@ -76,11 +74,9 @@ var M;
     }()); // error
     M.f = f;
 })(M || (M = {}));
-var M;
 (function (M) {
     function g() { }
 })(M || (M = {}));
-var M;
 (function (M) {
     var g = (function () {
         function g() {
@@ -89,7 +85,6 @@ var M;
     }()); // no error
     M.g = g;
 })(M || (M = {}));
-var M;
 (function (M) {
     var C = (function () {
         function C() {
@@ -98,15 +93,12 @@ var M;
     }());
     M.C = C;
 })(M || (M = {}));
-var M;
 (function (M) {
     function C() { } // no error
 })(M || (M = {}));
-var M;
 (function (M) {
     M.v = 3;
 })(M || (M = {}));
-var M;
 (function (M) {
     M.v = 3; // error for redeclaring var in a different parent
 })(M || (M = {}));
@@ -115,7 +107,6 @@ var Foo = (function () {
     }
     return Foo;
 }());
-var Foo;
 (function (Foo) {
 })(Foo || (Foo = {}));
 var N;
diff --git a/tests/baselines/reference/duplicateSymbolsExportMatching.js b/tests/baselines/reference/duplicateSymbolsExportMatching.js
index bb04e3c72a4..9f977f5fd58 100644
--- a/tests/baselines/reference/duplicateSymbolsExportMatching.js
+++ b/tests/baselines/reference/duplicateSymbolsExportMatching.js
@@ -75,7 +75,6 @@ define(["require", "exports"], function (require, exports) {
         (function (inst) {
             var t;
         })(inst || (inst = {}));
-        var inst;
         (function (inst) {
             var t;
         })(inst = M.inst || (M.inst = {}));
@@ -86,7 +85,6 @@ define(["require", "exports"], function (require, exports) {
         var v;
         var w;
     })(M2 || (M2 = {}));
-    var M;
     (function (M) {
         var F;
         (function (F) {
@@ -95,14 +93,12 @@ define(["require", "exports"], function (require, exports) {
         function F() { } // Only one error for duplicate identifier (don't consider visibility)
         M.F = F;
     })(M || (M = {}));
-    var M;
     (function (M) {
         var C = (function () {
             function C() {
             }
             return C;
         }());
-        var C;
         (function (C) {
             var t;
         })(C = M.C || (M.C = {}));
diff --git a/tests/baselines/reference/enumAssignabilityInInheritance.js b/tests/baselines/reference/enumAssignabilityInInheritance.js
index dc5237108f5..c5ff19cf239 100644
--- a/tests/baselines/reference/enumAssignabilityInInheritance.js
+++ b/tests/baselines/reference/enumAssignabilityInInheritance.js
@@ -145,7 +145,6 @@ var E2;
 })(E2 || (E2 = {}));
 var r4 = foo13(E.A);
 function f() { }
-var f;
 (function (f) {
     f.bar = 1;
 })(f || (f = {}));
@@ -155,7 +154,6 @@ var CC = (function () {
     }
     return CC;
 }());
-var CC;
 (function (CC) {
     CC.bar = 1;
 })(CC || (CC = {}));
diff --git a/tests/baselines/reference/enumAssignmentCompat.js b/tests/baselines/reference/enumAssignmentCompat.js
index b4762d182d4..9cdac291b99 100644
--- a/tests/baselines/reference/enumAssignmentCompat.js
+++ b/tests/baselines/reference/enumAssignmentCompat.js
@@ -48,7 +48,6 @@ var W;
     }());
     W.D = D;
 })(W || (W = {}));
-var W;
 (function (W) {
     W[W["a"] = 0] = "a";
     W[W["b"] = 1] = "b";
diff --git a/tests/baselines/reference/enumAssignmentCompat2.js b/tests/baselines/reference/enumAssignmentCompat2.js
index 0cc3b6befbf..5675bc86fe0 100644
--- a/tests/baselines/reference/enumAssignmentCompat2.js
+++ b/tests/baselines/reference/enumAssignmentCompat2.js
@@ -44,7 +44,6 @@ var W;
     W[W["b"] = 1] = "b";
     W[W["c"] = 2] = "c";
 })(W || (W = {}));
-var W;
 (function (W) {
     var D = (function () {
         function D() {
diff --git a/tests/baselines/reference/enumAssignmentCompat3.js b/tests/baselines/reference/enumAssignmentCompat3.js
index 74f74ab1652..62f05c18b5f 100644
--- a/tests/baselines/reference/enumAssignmentCompat3.js
+++ b/tests/baselines/reference/enumAssignmentCompat3.js
@@ -164,7 +164,6 @@ var Merged2;
         E[E["c"] = 2] = "c";
     })(Merged2.E || (Merged2.E = {}));
     var E = Merged2.E;
-    var E;
     (function (E) {
         E.d = 5;
     })(E = Merged2.E || (Merged2.E = {}));
diff --git a/tests/baselines/reference/enumBasics1.js b/tests/baselines/reference/enumBasics1.js
index e5c9c6d29d4..76e60cde355 100644
--- a/tests/baselines/reference/enumBasics1.js
+++ b/tests/baselines/reference/enumBasics1.js
@@ -69,7 +69,6 @@ var E2;
     E2[E2["A"] = 0] = "A";
     E2[E2["B"] = 1] = "B";
 })(E2 || (E2 = {}));
-var E2;
 (function (E2) {
     E2[E2["C"] = 0] = "C";
     E2[E2["D"] = 1] = "D";
diff --git a/tests/baselines/reference/enumGenericTypeClash.js b/tests/baselines/reference/enumGenericTypeClash.js
index 931df9f9d98..31c41be85c2 100644
--- a/tests/baselines/reference/enumGenericTypeClash.js
+++ b/tests/baselines/reference/enumGenericTypeClash.js
@@ -9,7 +9,6 @@ var X = (function () {
     }
     return X;
 }());
-var X;
 (function (X) {
     X[X["MyVal"] = 0] = "MyVal";
 })(X || (X = {}));
diff --git a/tests/baselines/reference/enumIsNotASubtypeOfAnythingButNumber.js b/tests/baselines/reference/enumIsNotASubtypeOfAnythingButNumber.js
index 56f40eef6e0..9cb6169b2af 100644
--- a/tests/baselines/reference/enumIsNotASubtypeOfAnythingButNumber.js
+++ b/tests/baselines/reference/enumIsNotASubtypeOfAnythingButNumber.js
@@ -151,7 +151,6 @@ var E2;
     E2[E2["A"] = 0] = "A";
 })(E2 || (E2 = {}));
 function f() { }
-var f;
 (function (f) {
     f.bar = 1;
 })(f || (f = {}));
@@ -160,7 +159,6 @@ var c = (function () {
     }
     return c;
 }());
-var c;
 (function (c) {
     c.bar = 1;
 })(c || (c = {}));
diff --git a/tests/baselines/reference/enumMerging.js b/tests/baselines/reference/enumMerging.js
index 5dc5a475b40..d830b03cac9 100644
--- a/tests/baselines/reference/enumMerging.js
+++ b/tests/baselines/reference/enumMerging.js
@@ -77,7 +77,6 @@ var M1;
         EImpl1[EImpl1["B"] = 1] = "B";
         EImpl1[EImpl1["C"] = 2] = "C";
     })(EImpl1 || (EImpl1 = {}));
-    var EImpl1;
     (function (EImpl1) {
         EImpl1[EImpl1["D"] = 1] = "D";
         EImpl1[EImpl1["E"] = 2] = "E";
@@ -122,7 +121,6 @@ var M3;
         EInit[EInit["A"] = 0] = "A";
         EInit[EInit["B"] = 1] = "B";
     })(EInit || (EInit = {}));
-    var EInit;
     (function (EInit) {
         EInit[EInit["C"] = 1] = "C";
         EInit[EInit["D"] = 2] = "D";
@@ -160,7 +158,6 @@ var M6;
         var Color = A.Color;
     })(A = M6.A || (M6.A = {}));
 })(M6 || (M6 = {}));
-var M6;
 (function (M6) {
     var A;
     (function (A) {
diff --git a/tests/baselines/reference/enumMergingErrors.js b/tests/baselines/reference/enumMergingErrors.js
index 46855093816..c9b4aaef754 100644
--- a/tests/baselines/reference/enumMergingErrors.js
+++ b/tests/baselines/reference/enumMergingErrors.js
@@ -59,7 +59,6 @@ var M;
     })(M.E3 || (M.E3 = {}));
     var E3 = M.E3;
 })(M || (M = {}));
-var M;
 (function (M) {
     (function (E1) {
         E1[E1["B"] = 'foo'.length] = "B";
@@ -74,7 +73,6 @@ var M;
     })(M.E3 || (M.E3 = {}));
     var E3 = M.E3;
 })(M || (M = {}));
-var M;
 (function (M) {
     (function (E1) {
         E1[E1["C"] = 0] = "C";
@@ -97,14 +95,12 @@ var M1;
     })(M1.E1 || (M1.E1 = {}));
     var E1 = M1.E1;
 })(M1 || (M1 = {}));
-var M1;
 (function (M1) {
     (function (E1) {
         E1[E1["B"] = 0] = "B";
     })(M1.E1 || (M1.E1 = {}));
     var E1 = M1.E1;
 })(M1 || (M1 = {}));
-var M1;
 (function (M1) {
     (function (E1) {
         E1[E1["C"] = 0] = "C";
@@ -119,14 +115,12 @@ var M2;
     })(M2.E1 || (M2.E1 = {}));
     var E1 = M2.E1;
 })(M2 || (M2 = {}));
-var M2;
 (function (M2) {
     (function (E1) {
         E1[E1["B"] = 0] = "B";
     })(M2.E1 || (M2.E1 = {}));
     var E1 = M2.E1;
 })(M2 || (M2 = {}));
-var M2;
 (function (M2) {
     (function (E1) {
         E1[E1["C"] = 0] = "C";
diff --git a/tests/baselines/reference/enumsWithMultipleDeclarations1.js b/tests/baselines/reference/enumsWithMultipleDeclarations1.js
index 35da126205d..67bca48db53 100644
--- a/tests/baselines/reference/enumsWithMultipleDeclarations1.js
+++ b/tests/baselines/reference/enumsWithMultipleDeclarations1.js
@@ -16,11 +16,9 @@ var E;
 (function (E) {
     E[E["A"] = 0] = "A";
 })(E || (E = {}));
-var E;
 (function (E) {
     E[E["B"] = 0] = "B";
 })(E || (E = {}));
-var E;
 (function (E) {
     E[E["C"] = 0] = "C";
 })(E || (E = {}));
diff --git a/tests/baselines/reference/enumsWithMultipleDeclarations2.js b/tests/baselines/reference/enumsWithMultipleDeclarations2.js
index 53d0d717711..55cab82bbc5 100644
--- a/tests/baselines/reference/enumsWithMultipleDeclarations2.js
+++ b/tests/baselines/reference/enumsWithMultipleDeclarations2.js
@@ -16,11 +16,9 @@ var E;
 (function (E) {
     E[E["A"] = 0] = "A";
 })(E || (E = {}));
-var E;
 (function (E) {
     E[E["B"] = 1] = "B";
 })(E || (E = {}));
-var E;
 (function (E) {
     E[E["C"] = 0] = "C";
 })(E || (E = {}));
diff --git a/tests/baselines/reference/es6modulekindWithES5Target12.js b/tests/baselines/reference/es6modulekindWithES5Target12.js
new file mode 100644
index 00000000000..316718e6f80
--- /dev/null
+++ b/tests/baselines/reference/es6modulekindWithES5Target12.js
@@ -0,0 +1,70 @@
+//// [es6modulekindWithES5Target12.ts]
+
+export class C {
+}
+
+export namespace C {
+    export const x = 1;
+}
+
+export enum E {
+    w = 1
+}
+
+export enum E {
+    x = 2
+}
+
+export namespace E {
+    export const y = 1;
+}
+
+export namespace E {
+    export const z = 1;
+}
+
+export namespace N {
+}
+
+export namespace N {
+    export const x = 1;
+}
+
+export function F() {
+}
+
+export namespace F {
+    export const x = 1;
+}
+
+//// [es6modulekindWithES5Target12.js]
+export var C = (function () {
+    function C() {
+    }
+    return C;
+}());
+(function (C) {
+    C.x = 1;
+})(C || (C = {}));
+export var E;
+(function (E) {
+    E[E["w"] = 1] = "w";
+})(E || (E = {}));
+(function (E) {
+    E[E["x"] = 2] = "x";
+})(E || (E = {}));
+(function (E) {
+    E.y = 1;
+})(E || (E = {}));
+(function (E) {
+    E.z = 1;
+})(E || (E = {}));
+export var N;
+(function (N) {
+    N.x = 1;
+})(N || (N = {}));
+export function F() {
+}
+(function (F) {
+    F.x = 1;
+})(F || (F = {}));
diff --git a/tests/baselines/reference/es6modulekindWithES5Target12.symbols b/tests/baselines/reference/es6modulekindWithES5Target12.symbols
new file mode 100644
index 00000000000..e6469a6300a
--- /dev/null
+++ b/tests/baselines/reference/es6modulekindWithES5Target12.symbols
@@ -0,0 +1,62 @@
+=== tests/cases/compiler/es6modulekindWithES5Target12.ts ===
+
+export class C {
+>C : Symbol(C, Decl(es6modulekindWithES5Target12.ts, 0, 0), Decl(es6modulekindWithES5Target12.ts, 2, 1))
+}
+
+export namespace C {
+>C : Symbol(C, Decl(es6modulekindWithES5Target12.ts, 0, 0), Decl(es6modulekindWithES5Target12.ts, 2, 1))
+
+    export const x = 1;
+>x : Symbol(x, Decl(es6modulekindWithES5Target12.ts, 5, 16))
+}
+
+export enum E {
+>E : Symbol(E, Decl(es6modulekindWithES5Target12.ts, 6, 1), Decl(es6modulekindWithES5Target12.ts, 10, 1), Decl(es6modulekindWithES5Target12.ts, 14, 1), Decl(es6modulekindWithES5Target12.ts, 18, 1))
+
+    w = 1
+>w : Symbol(E.w, Decl(es6modulekindWithES5Target12.ts, 8, 15))
+}
+
+export enum E {
+>E : Symbol(E, Decl(es6modulekindWithES5Target12.ts, 6, 1), Decl(es6modulekindWithES5Target12.ts, 10, 1), Decl(es6modulekindWithES5Target12.ts, 14, 1), Decl(es6modulekindWithES5Target12.ts, 18, 1))
+
+    x = 2
+>x : Symbol(E.x, Decl(es6modulekindWithES5Target12.ts, 12, 15))
+}
+
+export namespace E {
+>E : Symbol(E, Decl(es6modulekindWithES5Target12.ts, 6, 1), Decl(es6modulekindWithES5Target12.ts, 10, 1), Decl(es6modulekindWithES5Target12.ts, 14, 1), Decl(es6modulekindWithES5Target12.ts, 18, 1))
+
+    export const y = 1;
+>y : Symbol(y, Decl(es6modulekindWithES5Target12.ts, 17, 16))
+}
+
+export namespace E {
+>E : Symbol(E, Decl(es6modulekindWithES5Target12.ts, 6, 1), Decl(es6modulekindWithES5Target12.ts, 10, 1), Decl(es6modulekindWithES5Target12.ts, 14, 1), Decl(es6modulekindWithES5Target12.ts, 18, 1))
+
+    export const z = 1;
+>z : Symbol(z, Decl(es6modulekindWithES5Target12.ts, 21, 16))
+}
+
+export namespace N {
+>N : Symbol(N, Decl(es6modulekindWithES5Target12.ts, 22, 1), Decl(es6modulekindWithES5Target12.ts, 25, 1))
+}
+
+export namespace N {
+>N : Symbol(N, Decl(es6modulekindWithES5Target12.ts, 22, 1), Decl(es6modulekindWithES5Target12.ts, 25, 1))
+
+    export const x = 1;
+>x : Symbol(x, Decl(es6modulekindWithES5Target12.ts, 28, 16))
+}
+
+export function F() {
+>F : Symbol(F, Decl(es6modulekindWithES5Target12.ts, 29, 1), Decl(es6modulekindWithES5Target12.ts, 32, 1))
+}
+
+export namespace F {
+>F : Symbol(F, Decl(es6modulekindWithES5Target12.ts, 29, 1), Decl(es6modulekindWithES5Target12.ts, 32, 1))
+
+    export const x = 1;
+>x : Symbol(x, Decl(es6modulekindWithES5Target12.ts, 35, 16))
+}
diff --git a/tests/baselines/reference/es6modulekindWithES5Target12.types b/tests/baselines/reference/es6modulekindWithES5Target12.types
new file mode 100644
index 00000000000..5bc42cae68a
--- /dev/null
+++ b/tests/baselines/reference/es6modulekindWithES5Target12.types
@@ -0,0 +1,69 @@
+=== tests/cases/compiler/es6modulekindWithES5Target12.ts ===
+
+export class C {
+>C : C
+}
+
+export namespace C {
+>C : typeof C
+
+    export const x = 1;
+>x : 1
+>1 : 1
+}
+
+export enum E {
+>E : E
+
+    w = 1
+>w : E.w
+>1 : 1
+}
+
+export enum E {
+>E : E
+
+    x = 2
+>x : E.x
+>2 : 2
+}
+
+export namespace E {
+>E : typeof E
+
+    export const y = 1;
+>y : 1
+>1 : 1
+}
+
+export namespace E {
+>E : typeof E
+
+    export const z = 1;
+>z : 1
+>1 : 1
+}
+
+export namespace N {
+>N : typeof N
+}
+
+export namespace N {
+>N : typeof N
+
+    export const x = 1;
+>x : 1
+>1 : 1
+}
+
+export function F() {
+>F : typeof F
+}
+
+export namespace F {
+>F : typeof F
+
+    export const x = 1;
+>x : 1
+>1 : 1
+}
diff --git a/tests/baselines/reference/exportAssignmentMergedModule.js b/tests/baselines/reference/exportAssignmentMergedModule.js
index 8d78799a05b..aa2a7082f76 100644
--- a/tests/baselines/reference/exportAssignmentMergedModule.js
+++ b/tests/baselines/reference/exportAssignmentMergedModule.js
@@ -34,7 +34,6 @@ var Foo;
     Foo.a = a;
     Foo.b = true;
 })(Foo || (Foo = {}));
-var Foo;
 (function (Foo) {
     function c(a) {
         return a;
diff --git a/tests/baselines/reference/exportAssignmentTopLevelClodule.js b/tests/baselines/reference/exportAssignmentTopLevelClodule.js
index 08220cc8de3..9e073462aac 100644
--- a/tests/baselines/reference/exportAssignmentTopLevelClodule.js
+++ b/tests/baselines/reference/exportAssignmentTopLevelClodule.js
@@ -25,7 +25,6 @@ define(["require", "exports"], function (require, exports) {
         }
         return Foo;
     }());
-    var Foo;
     (function (Foo) {
         Foo.answer = 42;
     })(Foo || (Foo = {}));
diff --git a/tests/baselines/reference/exportAssignmentTopLevelEnumdule.js b/tests/baselines/reference/exportAssignmentTopLevelEnumdule.js
index 2516b1b0e28..5043a684326 100644
--- a/tests/baselines/reference/exportAssignmentTopLevelEnumdule.js
+++ b/tests/baselines/reference/exportAssignmentTopLevelEnumdule.js
@@ -26,7 +26,6 @@ define(["require", "exports"], function (require, exports) {
         foo[foo["green"] = 1] = "green";
         foo[foo["blue"] = 2] = "blue";
     })(foo || (foo = {}));
-    var foo;
     (function (foo) {
         foo.answer = 42;
     })(foo || (foo = {}));
diff --git a/tests/baselines/reference/exportAssignmentTopLevelFundule.js b/tests/baselines/reference/exportAssignmentTopLevelFundule.js
index d151a61d539..0549700e464 100644
--- a/tests/baselines/reference/exportAssignmentTopLevelFundule.js
+++ b/tests/baselines/reference/exportAssignmentTopLevelFundule.js
@@ -22,7 +22,6 @@ define(["require", "exports"], function (require, exports) {
     function foo() {
         return "test";
     }
-    var foo;
     (function (foo) {
         foo.answer = 42;
     })(foo || (foo = {}));
diff --git a/tests/baselines/reference/exportDeclarationInInternalModule.js b/tests/baselines/reference/exportDeclarationInInternalModule.js
index a9ea4bf5eda..465c085fa02 100644
--- a/tests/baselines/reference/exportDeclarationInInternalModule.js
+++ b/tests/baselines/reference/exportDeclarationInInternalModule.js
@@ -36,7 +36,6 @@ var Aaa = (function (_super) {
     }
     return Aaa;
 }(Bbb));
-var Aaa;
 (function (Aaa) {
     var SomeType = (function () {
         function SomeType() {
@@ -45,7 +44,6 @@ var Aaa;
     }());
     Aaa.SomeType = SomeType;
 })(Aaa || (Aaa = {}));
-var Bbb;
 (function (Bbb) {
     var SomeType = (function () {
         function SomeType() {
diff --git a/tests/baselines/reference/exportDefaultProperty.js b/tests/baselines/reference/exportDefaultProperty.js
index 10ba6d6419a..2dcef41d761 100644
--- a/tests/baselines/reference/exportDefaultProperty.js
+++ b/tests/baselines/reference/exportDefaultProperty.js
@@ -51,7 +51,6 @@ var A;
         return B;
     }());
     A.B = B;
-    var B;
     (function (B) {
         B.b = 0;
     })(B = A.B || (A.B = {}));
diff --git a/tests/baselines/reference/exportEqualsProperty.js b/tests/baselines/reference/exportEqualsProperty.js
index 2fd8a8c8511..9acb1ee49b7 100644
--- a/tests/baselines/reference/exportEqualsProperty.js
+++ b/tests/baselines/reference/exportEqualsProperty.js
@@ -50,7 +50,6 @@ var A;
         return B;
     }());
     A.B = B;
-    var B;
     (function (B) {
         B.b = 0;
     })(B = A.B || (A.B = {}));
diff --git a/tests/baselines/reference/exportImportAlias.js b/tests/baselines/reference/exportImportAlias.js
index be77f755368..3f9bc18f45b 100644
--- a/tests/baselines/reference/exportImportAlias.js
+++ b/tests/baselines/reference/exportImportAlias.js
@@ -96,7 +96,6 @@ var X;
         return 42;
     }
     X.Y = Y;
-    var Y;
     (function (Y) {
         var Point = (function () {
             function Point(x, y) {
@@ -124,7 +123,6 @@ var K;
         return L;
     }());
     K.L = L;
-    var L;
     (function (L) {
         L.y = 12;
     })(L = K.L || (K.L = {}));
diff --git a/tests/baselines/reference/exportImportAndClodule.js b/tests/baselines/reference/exportImportAndClodule.js
index e519d555792..842b97c0871 100644
--- a/tests/baselines/reference/exportImportAndClodule.js
+++ b/tests/baselines/reference/exportImportAndClodule.js
@@ -29,7 +29,6 @@ var K;
         return L;
     }());
     K.L = L;
-    var L;
     (function (L) {
         L.y = 12;
     })(L = K.L || (K.L = {}));
diff --git a/tests/baselines/reference/extBaseClass1.js b/tests/baselines/reference/extBaseClass1.js
index 446c6df9c94..86eda4d5d66 100644
--- a/tests/baselines/reference/extBaseClass1.js
+++ b/tests/baselines/reference/extBaseClass1.js
@@ -43,7 +43,6 @@ var M;
     }(B));
     M.C = C;
 })(M || (M = {}));
-var M;
 (function (M) {
     var C2 = (function (_super) {
         __extends(C2, _super);
diff --git a/tests/baselines/reference/forwardRefInEnum.js b/tests/baselines/reference/forwardRefInEnum.js
index 76e2575ec8d..555454dccaa 100644
--- a/tests/baselines/reference/forwardRefInEnum.js
+++ b/tests/baselines/reference/forwardRefInEnum.js
@@ -25,7 +25,6 @@ var E1;
     E1[E1["Y"] = E1.Z] = "Y";
     E1[E1["Y1"] = E1["Z"]] = "Y1";
 })(E1 || (E1 = {}));
-var E1;
 (function (E1) {
     E1[E1["Z"] = 4] = "Z";
 })(E1 || (E1 = {}));
diff --git a/tests/baselines/reference/funClodule.js b/tests/baselines/reference/funClodule.js
index 8ea98ad7487..b2c18bf3786 100644
--- a/tests/baselines/reference/funClodule.js
+++ b/tests/baselines/reference/funClodule.js
@@ -21,7 +21,6 @@ class foo3 { } // Should error
 
 //// [funClodule.js]
 function foo3() { }
-var foo3;
 (function (foo3) {
     function x() { }
     foo3.x = x;
diff --git a/tests/baselines/reference/functionMergedWithModule.js b/tests/baselines/reference/functionMergedWithModule.js
index d83c1cd4e37..9265ee9bc1f 100644
--- a/tests/baselines/reference/functionMergedWithModule.js
+++ b/tests/baselines/reference/functionMergedWithModule.js
@@ -18,7 +18,6 @@ module foo.Baz {
 function foo(title) {
     var x = 10;
 }
-var foo;
 (function (foo) {
     var Bar;
     (function (Bar) {
@@ -27,7 +26,6 @@ var foo;
         Bar.f = f;
     })(Bar = foo.Bar || (foo.Bar = {}));
 })(foo || (foo = {}));
-var foo;
 (function (foo) {
     var Baz;
     (function (Baz) {
diff --git a/tests/baselines/reference/funduleOfFunctionWithoutReturnTypeAnnotation.js b/tests/baselines/reference/funduleOfFunctionWithoutReturnTypeAnnotation.js
index 36356b1f6ed..868a755bf7e 100644
--- a/tests/baselines/reference/funduleOfFunctionWithoutReturnTypeAnnotation.js
+++ b/tests/baselines/reference/funduleOfFunctionWithoutReturnTypeAnnotation.js
@@ -11,7 +11,6 @@ module fn {
 function fn() {
     return fn.n;
 }
-var fn;
 (function (fn) {
     fn.n = 1;
 })(fn || (fn = {}));
diff --git a/tests/baselines/reference/genericCloduleInModule.js b/tests/baselines/reference/genericCloduleInModule.js
index e3f926e1f91..6164bfc0904 100644
--- a/tests/baselines/reference/genericCloduleInModule.js
+++ b/tests/baselines/reference/genericCloduleInModule.js
@@ -23,7 +23,6 @@ var A;
         return B;
     }());
     A.B = B;
-    var B;
     (function (B) {
         B.x = 1;
     })(B = A.B || (A.B = {}));
diff --git a/tests/baselines/reference/genericCloduleInModule2.js b/tests/baselines/reference/genericCloduleInModule2.js
index 433a165db92..55a5507eed2 100644
--- a/tests/baselines/reference/genericCloduleInModule2.js
+++ b/tests/baselines/reference/genericCloduleInModule2.js
@@ -27,7 +27,6 @@ var A;
     }());
     A.B = B;
 })(A || (A = {}));
-var A;
 (function (A) {
     var B;
     (function (B) {
diff --git a/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes.js b/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes.js
index d2bf12667fc..a1ae3a0f06b 100644
--- a/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes.js
+++ b/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes.js
@@ -45,7 +45,6 @@ var EndGate;
         Tweening.Tween = Tween;
     })(Tweening = EndGate.Tweening || (EndGate.Tweening = {}));
 })(EndGate || (EndGate = {}));
-var EndGate;
 (function (EndGate) {
     var Tweening;
     (function (Tweening) {
diff --git a/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes2.js b/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes2.js
index f61f57cb615..810c25b77d4 100644
--- a/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes2.js
+++ b/tests/baselines/reference/genericConstraintOnExtendedBuiltinTypes2.js
@@ -44,7 +44,6 @@ var EndGate;
         Tweening.Tween = Tween;
     })(Tweening = EndGate.Tweening || (EndGate.Tweening = {}));
 })(EndGate || (EndGate = {}));
-var EndGate;
 (function (EndGate) {
     var Tweening;
     (function (Tweening) {
diff --git a/tests/baselines/reference/genericFunduleInModule.js b/tests/baselines/reference/genericFunduleInModule.js
index 95700edecab..9bd1e47b420 100644
--- a/tests/baselines/reference/genericFunduleInModule.js
+++ b/tests/baselines/reference/genericFunduleInModule.js
@@ -14,7 +14,6 @@ var A;
 (function (A) {
     function B(x) { return x; }
     A.B = B;
-    var B;
     (function (B) {
         B.x = 1;
     })(B = A.B || (A.B = {}));
diff --git a/tests/baselines/reference/genericFunduleInModule2.js b/tests/baselines/reference/genericFunduleInModule2.js
index 956e9129ec7..2523b4fe126 100644
--- a/tests/baselines/reference/genericFunduleInModule2.js
+++ b/tests/baselines/reference/genericFunduleInModule2.js
@@ -18,7 +18,6 @@ var A;
     function B(x) { return x; }
     A.B = B;
 })(A || (A = {}));
-var A;
 (function (A) {
     var B;
     (function (B) {
diff --git a/tests/baselines/reference/genericMergedDeclarationUsingTypeParameter.js b/tests/baselines/reference/genericMergedDeclarationUsingTypeParameter.js
index 6dd456ab703..56a64e8934f 100644
--- a/tests/baselines/reference/genericMergedDeclarationUsingTypeParameter.js
+++ b/tests/baselines/reference/genericMergedDeclarationUsingTypeParameter.js
@@ -8,7 +8,6 @@ module foo {
 
 //// [genericMergedDeclarationUsingTypeParameter.js]
 function foo(y, z) { return y; }
-var foo;
 (function (foo) {
     var y = 1;
 })(foo || (foo = {}));
diff --git a/tests/baselines/reference/genericMergedDeclarationUsingTypeParameter2.js b/tests/baselines/reference/genericMergedDeclarationUsingTypeParameter2.js
index ac51424deea..11a9c0891ae 100644
--- a/tests/baselines/reference/genericMergedDeclarationUsingTypeParameter2.js
+++ b/tests/baselines/reference/genericMergedDeclarationUsingTypeParameter2.js
@@ -12,7 +12,6 @@ var foo = (function () {
     }
     return foo;
 }());
-var foo;
 (function (foo) {
     var y = 1;
 })(foo || (foo = {}));
diff --git a/tests/baselines/reference/genericOfACloduleType1.js b/tests/baselines/reference/genericOfACloduleType1.js
index 3e4b9d3a9d4..1c9657ec8f1 100644
--- a/tests/baselines/reference/genericOfACloduleType1.js
+++ b/tests/baselines/reference/genericOfACloduleType1.js
@@ -28,7 +28,6 @@ var M;
         return C;
     }());
     M.C = C;
-    var C;
     (function (C) {
         var X = (function () {
             function X() {
diff --git a/tests/baselines/reference/genericOfACloduleType2.js b/tests/baselines/reference/genericOfACloduleType2.js
index f1e3f2a8a00..c96e3f4fa6d 100644
--- a/tests/baselines/reference/genericOfACloduleType2.js
+++ b/tests/baselines/reference/genericOfACloduleType2.js
@@ -31,7 +31,6 @@ var M;
         return C;
     }());
     M.C = C;
-    var C;
     (function (C) {
         var X = (function () {
             function X() {
diff --git a/tests/baselines/reference/genericRecursiveImplicitConstructorErrors3.js b/tests/baselines/reference/genericRecursiveImplicitConstructorErrors3.js
index 61cb758c48e..f1726e162c4 100644
--- a/tests/baselines/reference/genericRecursiveImplicitConstructorErrors3.js
+++ b/tests/baselines/reference/genericRecursiveImplicitConstructorErrors3.js
@@ -47,7 +47,6 @@ var TypeScript;
     }());
     TypeScript.MemberName = MemberName;
 })(TypeScript || (TypeScript = {}));
-var TypeScript;
 (function (TypeScript) {
     var PullSymbol = (function () {
         function PullSymbol() {
diff --git a/tests/baselines/reference/heterogeneousArrayLiterals.js b/tests/baselines/reference/heterogeneousArrayLiterals.js
index e482f0d33d3..2ebbfb7f7c6 100644
--- a/tests/baselines/reference/heterogeneousArrayLiterals.js
+++ b/tests/baselines/reference/heterogeneousArrayLiterals.js
@@ -174,7 +174,6 @@ var Derived2 = (function (_super) {
 var base;
 var derived;
 var derived2;
-var Derived;
 (function (Derived) {
     var h = [{ foo: base, basear: derived }, { foo: base }]; // {foo: Base}[]
     var i = [{ foo: base, basear: derived }, { foo: derived }]; // {foo: Derived}[]
diff --git a/tests/baselines/reference/importAliasIdentifiers.js b/tests/baselines/reference/importAliasIdentifiers.js
index 084b6694e9c..278c5a2e8a0 100644
--- a/tests/baselines/reference/importAliasIdentifiers.js
+++ b/tests/baselines/reference/importAliasIdentifiers.js
@@ -67,7 +67,6 @@ var clodule = (function () {
     }
     return clodule;
 }());
-var clodule;
 (function (clodule) {
     var Point = { x: 0, y: 0 };
 })(clodule || (clodule = {}));
@@ -78,7 +77,6 @@ var p;
 function fundule() {
     return { x: 0, y: 0 };
 }
-var fundule;
 (function (fundule) {
     var Point = { x: 0, y: 0 };
 })(fundule || (fundule = {}));
diff --git a/tests/baselines/reference/inheritedModuleMembersForClodule.js b/tests/baselines/reference/inheritedModuleMembersForClodule.js
index 95b71069584..b704fbf4118 100644
--- a/tests/baselines/reference/inheritedModuleMembersForClodule.js
+++ b/tests/baselines/reference/inheritedModuleMembersForClodule.js
@@ -42,7 +42,6 @@ var D = (function (_super) {
     }
     return D;
 }(C));
-var D;
 (function (D) {
     function foo() {
         return 0;
diff --git a/tests/baselines/reference/internalImportInstantiatedModuleMergedWithClassNotReferencingInstance.js b/tests/baselines/reference/internalImportInstantiatedModuleMergedWithClassNotReferencingInstance.js
index 8feecb53f98..a0c0e0b34fe 100644
--- a/tests/baselines/reference/internalImportInstantiatedModuleMergedWithClassNotReferencingInstance.js
+++ b/tests/baselines/reference/internalImportInstantiatedModuleMergedWithClassNotReferencingInstance.js
@@ -19,7 +19,6 @@ var A = (function () {
     }
     return A;
 }());
-var A;
 (function (A) {
     A.a = 10;
 })(A || (A = {}));
diff --git a/tests/baselines/reference/internalImportInstantiatedModuleMergedWithClassNotReferencingInstanceNoConflict.js b/tests/baselines/reference/internalImportInstantiatedModuleMergedWithClassNotReferencingInstanceNoConflict.js
index 27101bba5f9..5fc852cca40 100644
--- a/tests/baselines/reference/internalImportInstantiatedModuleMergedWithClassNotReferencingInstanceNoConflict.js
+++ b/tests/baselines/reference/internalImportInstantiatedModuleMergedWithClassNotReferencingInstanceNoConflict.js
@@ -18,7 +18,6 @@ var A = (function () {
     }
     return A;
 }());
-var A;
 (function (A) {
     A.a = 10;
 })(A || (A = {}));
diff --git a/tests/baselines/reference/invalidNestedModules.js b/tests/baselines/reference/invalidNestedModules.js
index 8b532ddd757..676817139f9 100644
--- a/tests/baselines/reference/invalidNestedModules.js
+++ b/tests/baselines/reference/invalidNestedModules.js
@@ -45,7 +45,6 @@ var A;
         })(C = B.C || (B.C = {}));
     })(B = A.B || (A.B = {}));
 })(A || (A = {}));
-var A;
 (function (A) {
     var B;
     (function (B) {
@@ -69,7 +68,6 @@ var M2;
         X.Point = Point;
     })(X = M2.X || (M2.X = {}));
 })(M2 || (M2 = {}));
-var M2;
 (function (M2) {
     var X;
     (function (X) {
diff --git a/tests/baselines/reference/isDeclarationVisibleNodeKinds.js b/tests/baselines/reference/isDeclarationVisibleNodeKinds.js
index e24032eb858..07bc9994742 100644
--- a/tests/baselines/reference/isDeclarationVisibleNodeKinds.js
+++ b/tests/baselines/reference/isDeclarationVisibleNodeKinds.js
@@ -79,7 +79,6 @@ var schema;
     schema_1.createValidator1 = createValidator1;
 })(schema || (schema = {}));
 // Constructor types
-var schema;
 (function (schema_2) {
     function createValidator2(schema) {
         return undefined;
@@ -87,7 +86,6 @@ var schema;
     schema_2.createValidator2 = createValidator2;
 })(schema || (schema = {}));
 // union types
-var schema;
 (function (schema_3) {
     function createValidator3(schema) {
         return undefined;
@@ -95,7 +93,6 @@ var schema;
     schema_3.createValidator3 = createValidator3;
 })(schema || (schema = {}));
 // Array types
-var schema;
 (function (schema_4) {
     function createValidator4(schema) {
         return undefined;
@@ -103,7 +100,6 @@ var schema;
     schema_4.createValidator4 = createValidator4;
 })(schema || (schema = {}));
 // TypeLiterals
-var schema;
 (function (schema_5) {
     function createValidator5(schema) {
         return undefined;
@@ -111,7 +107,6 @@ var schema;
     schema_5.createValidator5 = createValidator5;
 })(schema || (schema = {}));
 // Tuple types
-var schema;
 (function (schema_6) {
     function createValidator6(schema) {
         return undefined;
@@ -119,7 +114,6 @@ var schema;
     schema_6.createValidator6 = createValidator6;
 })(schema || (schema = {}));
 // Paren Types
-var schema;
 (function (schema_7) {
     function createValidator7(schema) {
         return undefined;
@@ -127,14 +121,12 @@ var schema;
     schema_7.createValidator7 = createValidator7;
 })(schema || (schema = {}));
 // Type reference
-var schema;
 (function (schema_8) {
     function createValidator8(schema) {
         return undefined;
     }
     schema_8.createValidator8 = createValidator8;
 })(schema || (schema = {}));
-var schema;
 (function (schema) {
     var T = (function () {
         function T() {
diff --git a/tests/baselines/reference/mergeThreeInterfaces2.js b/tests/baselines/reference/mergeThreeInterfaces2.js
index f853dad3a28..ef504a5f6ec 100644
--- a/tests/baselines/reference/mergeThreeInterfaces2.js
+++ b/tests/baselines/reference/mergeThreeInterfaces2.js
@@ -76,7 +76,6 @@ var M2;
     var r1 = a.foo;
     var r2 = a.bar;
 })(M2 || (M2 = {}));
-var M2;
 (function (M2) {
     var a;
     var r1 = a.foo;
@@ -84,7 +83,6 @@ var M2;
     var r3 = a.baz;
 })(M2 || (M2 = {}));
 // same as above but with an additional level of nesting and third module declaration
-var M2;
 (function (M2) {
     var M3;
     (function (M3) {
@@ -93,7 +91,6 @@ var M2;
         var r2 = a.bar;
     })(M3 = M2.M3 || (M2.M3 = {}));
 })(M2 || (M2 = {}));
-var M2;
 (function (M2) {
     var M3;
     (function (M3) {
@@ -103,7 +100,6 @@ var M2;
         var r3 = a.baz;
     })(M3 = M2.M3 || (M2.M3 = {}));
 })(M2 || (M2 = {}));
-var M2;
 (function (M2) {
     var M3;
     (function (M3) {
diff --git a/tests/baselines/reference/mergeTwoInterfaces2.js b/tests/baselines/reference/mergeTwoInterfaces2.js
index 4f45c8f821e..3ab21df428c 100644
--- a/tests/baselines/reference/mergeTwoInterfaces2.js
+++ b/tests/baselines/reference/mergeTwoInterfaces2.js
@@ -56,14 +56,12 @@ var M2;
     var r1 = a.foo;
     var r2 = a.bar;
 })(M2 || (M2 = {}));
-var M2;
 (function (M2) {
     var a;
     var r1 = a.foo;
     var r2 = a.bar;
 })(M2 || (M2 = {}));
 // same as above but with an additional level of nesting
-var M2;
 (function (M2) {
     var M3;
     (function (M3) {
@@ -72,7 +70,6 @@ var M2;
         var r2 = a.bar;
     })(M3 = M2.M3 || (M2.M3 = {}));
 })(M2 || (M2 = {}));
-var M2;
 (function (M2) {
     var M3;
     (function (M3) {
diff --git a/tests/baselines/reference/mergedDeclarations1.js b/tests/baselines/reference/mergedDeclarations1.js
index 641ff031ded..f8663d12549 100644
--- a/tests/baselines/reference/mergedDeclarations1.js
+++ b/tests/baselines/reference/mergedDeclarations1.js
@@ -20,7 +20,6 @@ var b = point.equals(p1, p2);
 function point(x, y) {
     return { x: x, y: y };
 }
-var point;
 (function (point) {
     point.origin = point(0, 0);
     function equals(p1, p2) {
diff --git a/tests/baselines/reference/mergedDeclarations2.js b/tests/baselines/reference/mergedDeclarations2.js
index 962346541cc..b35ec48f7a8 100644
--- a/tests/baselines/reference/mergedDeclarations2.js
+++ b/tests/baselines/reference/mergedDeclarations2.js
@@ -15,11 +15,9 @@ var Foo;
 (function (Foo) {
     Foo[Foo["b"] = 0] = "b";
 })(Foo || (Foo = {}));
-var Foo;
 (function (Foo) {
     Foo[Foo["a"] = 0] = "a";
 })(Foo || (Foo = {}));
-var Foo;
 (function (Foo) {
     Foo.x = b;
 })(Foo || (Foo = {}));
diff --git a/tests/baselines/reference/mergedDeclarations3.js b/tests/baselines/reference/mergedDeclarations3.js
index 272946b5075..ddf94b46e81 100644
--- a/tests/baselines/reference/mergedDeclarations3.js
+++ b/tests/baselines/reference/mergedDeclarations3.js
@@ -48,7 +48,6 @@ var M;
     })(M.Color || (M.Color = {}));
     var Color = M.Color;
 })(M || (M = {}));
-var M;
 (function (M) {
     var Color;
     (function (Color) {
@@ -56,27 +55,23 @@ var M;
     })(Color = M.Color || (M.Color = {}));
 })(M || (M = {}));
 var p = M.Color.Blue; // ok
-var M;
 (function (M) {
     function foo() {
     }
     M.foo = foo;
 })(M || (M = {}));
-var M;
 (function (M) {
     var foo;
     (function (foo) {
         foo.x = 1;
     })(foo || (foo = {}));
 })(M || (M = {}));
-var M;
 (function (M) {
     var foo;
     (function (foo) {
         foo.y = 2;
     })(foo = M.foo || (M.foo = {}));
 })(M || (M = {}));
-var M;
 (function (M) {
     var foo;
     (function (foo) {
diff --git a/tests/baselines/reference/mergedDeclarations4.js b/tests/baselines/reference/mergedDeclarations4.js
index 64fad6bd598..c47632b0a69 100644
--- a/tests/baselines/reference/mergedDeclarations4.js
+++ b/tests/baselines/reference/mergedDeclarations4.js
@@ -27,7 +27,6 @@ var M;
     M.f();
     var r = f.hello;
 })(M || (M = {}));
-var M;
 (function (M) {
     var f;
     (function (f) {
diff --git a/tests/baselines/reference/mergedEnumDeclarationCodeGen.js b/tests/baselines/reference/mergedEnumDeclarationCodeGen.js
index 57b6e8051f8..ecf2474430e 100644
--- a/tests/baselines/reference/mergedEnumDeclarationCodeGen.js
+++ b/tests/baselines/reference/mergedEnumDeclarationCodeGen.js
@@ -13,7 +13,6 @@ var E;
     E[E["a"] = 0] = "a";
     E[E["b"] = 0] = "b";
 })(E || (E = {}));
-var E;
 (function (E) {
     E[E["c"] = 0] = "c";
 })(E || (E = {}));
diff --git a/tests/baselines/reference/mergedModuleDeclarationCodeGen.js b/tests/baselines/reference/mergedModuleDeclarationCodeGen.js
index f71702386ec..573701d407b 100644
--- a/tests/baselines/reference/mergedModuleDeclarationCodeGen.js
+++ b/tests/baselines/reference/mergedModuleDeclarationCodeGen.js
@@ -29,7 +29,6 @@ var X;
         }());
     })(Y = X.Y || (X.Y = {}));
 })(X = exports.X || (exports.X = {}));
-var X;
 (function (X) {
     var Y;
     (function (Y) {
diff --git a/tests/baselines/reference/mergedModuleDeclarationCodeGen2.js b/tests/baselines/reference/mergedModuleDeclarationCodeGen2.js
index bb7c34e4ac5..224042ac571 100644
--- a/tests/baselines/reference/mergedModuleDeclarationCodeGen2.js
+++ b/tests/baselines/reference/mergedModuleDeclarationCodeGen2.js
@@ -20,7 +20,6 @@ var my;
         })(foo = data.foo || (data.foo = {}));
     })(data = my.data || (my.data = {}));
 })(my || (my = {}));
-var my;
 (function (my_1) {
     var data;
     (function (data_1) {
diff --git a/tests/baselines/reference/mergedModuleDeclarationCodeGen3.js b/tests/baselines/reference/mergedModuleDeclarationCodeGen3.js
index 4a002e88f3d..5b16fe16dd2 100644
--- a/tests/baselines/reference/mergedModuleDeclarationCodeGen3.js
+++ b/tests/baselines/reference/mergedModuleDeclarationCodeGen3.js
@@ -17,7 +17,6 @@ var my;
         data.buz = buz;
     })(data = my.data || (my.data = {}));
 })(my || (my = {}));
-var my;
 (function (my_1) {
     var data;
     (function (data_1) {
diff --git a/tests/baselines/reference/mergedModuleDeclarationCodeGen4.js b/tests/baselines/reference/mergedModuleDeclarationCodeGen4.js
index 3e4a2dcd308..9a351c5c55e 100644
--- a/tests/baselines/reference/mergedModuleDeclarationCodeGen4.js
+++ b/tests/baselines/reference/mergedModuleDeclarationCodeGen4.js
@@ -32,7 +32,6 @@ var superContain;
                 })(data = buz.data || (buz.data = {}));
             })(buz = my.buz || (my.buz = {}));
         })(my = contain_1.my || (contain_1.my = {}));
-        var my;
         (function (my_1) {
             var buz;
             (function (buz_1) {
diff --git a/tests/baselines/reference/mergedModuleDeclarationCodeGen5.js b/tests/baselines/reference/mergedModuleDeclarationCodeGen5.js
index a5bc2e8e56e..11a4773d63a 100644
--- a/tests/baselines/reference/mergedModuleDeclarationCodeGen5.js
+++ b/tests/baselines/reference/mergedModuleDeclarationCodeGen5.js
@@ -32,7 +32,6 @@ var M;
         })(plop = buz.plop || (buz.plop = {}));
     })(buz = M_1.buz || (M_1.buz = {}));
 })(M || (M = {}));
-var M;
 (function (M) {
     var buz;
     (function (buz_1) {
diff --git a/tests/baselines/reference/mergedModuleDeclarationWithSharedExportedVar.js b/tests/baselines/reference/mergedModuleDeclarationWithSharedExportedVar.js
index f2f45c621d0..df8c0f8470c 100644
--- a/tests/baselines/reference/mergedModuleDeclarationWithSharedExportedVar.js
+++ b/tests/baselines/reference/mergedModuleDeclarationWithSharedExportedVar.js
@@ -13,7 +13,6 @@ var M;
     M.v = 10;
     M.v;
 })(M || (M = {}));
-var M;
 (function (M) {
     M.v;
 })(M || (M = {}));
diff --git a/tests/baselines/reference/missingFunctionImplementation.js b/tests/baselines/reference/missingFunctionImplementation.js
index a452c8080b7..d9ab942cfc8 100644
--- a/tests/baselines/reference/missingFunctionImplementation.js
+++ b/tests/baselines/reference/missingFunctionImplementation.js
@@ -131,7 +131,6 @@ var C8 = (function () {
     }
     return C8;
 }());
-var C8;
 (function (C8) {
     function m(a, b) { }
     C8.m = m;
@@ -143,14 +142,12 @@ var C9 = (function () {
     C9.m = function (a) { };
     return C9;
 }());
-var C9;
 (function (C9) {
 })(C9 || (C9 = {}));
 // merged namespaces
 var N10;
 (function (N10) {
 })(N10 || (N10 = {}));
-var N10;
 (function (N10) {
     function m(a) { }
     N10.m = m;
@@ -161,7 +158,6 @@ var N12;
     function m(a) { }
     N12.m = m;
 })(N12 || (N12 = {}));
-var N12;
 (function (N12) {
     function m(a) { }
     N12.m = m;
diff --git a/tests/baselines/reference/moduleDuplicateIdentifiers.js b/tests/baselines/reference/moduleDuplicateIdentifiers.js
index 1da296d7d12..097192ac73c 100644
--- a/tests/baselines/reference/moduleDuplicateIdentifiers.js
+++ b/tests/baselines/reference/moduleDuplicateIdentifiers.js
@@ -48,7 +48,6 @@ var FooBar;
 (function (FooBar) {
     FooBar.member1 = 2;
 })(FooBar = exports.FooBar || (exports.FooBar = {}));
-var FooBar;
 (function (FooBar) {
     FooBar.member2 = 42;
 })(FooBar = exports.FooBar || (exports.FooBar = {}));
diff --git a/tests/baselines/reference/moduleMemberWithoutTypeAnnotation1.js b/tests/baselines/reference/moduleMemberWithoutTypeAnnotation1.js
index 090d6502d5b..e0e95b3c72b 100644
--- a/tests/baselines/reference/moduleMemberWithoutTypeAnnotation1.js
+++ b/tests/baselines/reference/moduleMemberWithoutTypeAnnotation1.js
@@ -61,7 +61,6 @@ var TypeScript;
         }());
     })(Parser = TypeScript.Parser || (TypeScript.Parser = {}));
 })(TypeScript || (TypeScript = {}));
-var TypeScript;
 (function (TypeScript) {
     ;
     ;
@@ -81,7 +80,6 @@ var TypeScript;
     }());
     TypeScript.PositionedToken = PositionedToken;
 })(TypeScript || (TypeScript = {}));
-var TypeScript;
 (function (TypeScript) {
     var SyntaxNode = (function () {
         function SyntaxNode() {
@@ -98,7 +96,6 @@ var TypeScript;
     }());
     TypeScript.SyntaxNode = SyntaxNode;
 })(TypeScript || (TypeScript = {}));
-var TypeScript;
 (function (TypeScript) {
     var Syntax;
     (function (Syntax) {
diff --git a/tests/baselines/reference/moduleMerge.js b/tests/baselines/reference/moduleMerge.js
index 04f2f511b8d..4e5aac120fc 100644
--- a/tests/baselines/reference/moduleMerge.js
+++ b/tests/baselines/reference/moduleMerge.js
@@ -36,7 +36,6 @@ var A;
         return B;
     }());
 })(A || (A = {}));
-var A;
 (function (A) {
     var B = (function () {
         function B() {
diff --git a/tests/baselines/reference/moduleReopenedTypeOtherBlock.js b/tests/baselines/reference/moduleReopenedTypeOtherBlock.js
index 3380cd0ec7d..007090a0c11 100644
--- a/tests/baselines/reference/moduleReopenedTypeOtherBlock.js
+++ b/tests/baselines/reference/moduleReopenedTypeOtherBlock.js
@@ -18,7 +18,6 @@ var M;
     }());
     M.C1 = C1;
 })(M || (M = {}));
-var M;
 (function (M) {
     var C2 = (function () {
         function C2() {
diff --git a/tests/baselines/reference/moduleReopenedTypeSameBlock.js b/tests/baselines/reference/moduleReopenedTypeSameBlock.js
index b9624e75b75..07b5e8e657e 100644
--- a/tests/baselines/reference/moduleReopenedTypeSameBlock.js
+++ b/tests/baselines/reference/moduleReopenedTypeSameBlock.js
@@ -16,7 +16,6 @@ var M;
     }());
     M.C1 = C1;
 })(M || (M = {}));
-var M;
 (function (M) {
     var C2 = (function () {
         function C2() {
diff --git a/tests/baselines/reference/moduleVariables.js b/tests/baselines/reference/moduleVariables.js
index e127fec768f..3f5047c6266 100644
--- a/tests/baselines/reference/moduleVariables.js
+++ b/tests/baselines/reference/moduleVariables.js
@@ -24,11 +24,9 @@ var M;
     M.x = 2;
     console.log(M.x); // 2
 })(M || (M = {}));
-var M;
 (function (M) {
     console.log(M.x); // 2
 })(M || (M = {}));
-var M;
 (function (M) {
     var x = 3;
     console.log(x); // 3
diff --git a/tests/baselines/reference/moduleVisibilityTest1.js b/tests/baselines/reference/moduleVisibilityTest1.js
index 3278613409d..52afcf169d9 100644
--- a/tests/baselines/reference/moduleVisibilityTest1.js
+++ b/tests/baselines/reference/moduleVisibilityTest1.js
@@ -116,7 +116,6 @@ var M;
     var someModuleVar = 4;
     function someModuleFunction() { return 5; }
 })(M || (M = {}));
-var M;
 (function (M) {
     M.c = M.x;
     M.meb = M.E.B;
diff --git a/tests/baselines/reference/moduleVisibilityTest2.js b/tests/baselines/reference/moduleVisibilityTest2.js
index 51f3b00255b..62b12b87808 100644
--- a/tests/baselines/reference/moduleVisibilityTest2.js
+++ b/tests/baselines/reference/moduleVisibilityTest2.js
@@ -117,7 +117,6 @@ var M;
     var someModuleVar = 4;
     function someModuleFunction() { return 5; }
 })(M || (M = {}));
-var M;
 (function (M) {
     M.c = x;
     M.meb = M.E.B;
diff --git a/tests/baselines/reference/moduledecl.js b/tests/baselines/reference/moduledecl.js
index f4efbadbf3e..437907017fc 100644
--- a/tests/baselines/reference/moduledecl.js
+++ b/tests/baselines/reference/moduledecl.js
@@ -278,7 +278,6 @@ var m;
     (function (m3) {
     })(m3 = m.m3 || (m.m3 = {}));
 })(m || (m = {}));
-var m;
 (function (m) {
     var m25;
     (function (m25) {
diff --git a/tests/baselines/reference/multiModuleClodule1.js b/tests/baselines/reference/multiModuleClodule1.js
index b5b11058368..eac6bfa8d51 100644
--- a/tests/baselines/reference/multiModuleClodule1.js
+++ b/tests/baselines/reference/multiModuleClodule1.js
@@ -27,12 +27,10 @@ var C = (function () {
     C.boo = function () { };
     return C;
 }());
-var C;
 (function (C) {
     C.x = 1;
     var y = 2;
 })(C || (C = {}));
-var C;
 (function (C) {
     function foo() { }
     C.foo = foo;
diff --git a/tests/baselines/reference/multiModuleFundule1.js b/tests/baselines/reference/multiModuleFundule1.js
index 6aa9cb959ba..43bfe0b35fa 100644
--- a/tests/baselines/reference/multiModuleFundule1.js
+++ b/tests/baselines/reference/multiModuleFundule1.js
@@ -14,11 +14,9 @@ var r3 = C.foo();
 
 //// [multiModuleFundule1.js]
 function C(x) { }
-var C;
 (function (C) {
     C.x = 1;
 })(C || (C = {}));
-var C;
 (function (C) {
     function foo() { }
     C.foo = foo;
diff --git a/tests/baselines/reference/multipleExports.js b/tests/baselines/reference/multipleExports.js
index c70a5005aab..fd6ac67e82a 100644
--- a/tests/baselines/reference/multipleExports.js
+++ b/tests/baselines/reference/multipleExports.js
@@ -19,7 +19,6 @@ var M;
     M.v = 0;
 })(M = exports.M || (exports.M = {}));
 var x = 0;
-var M;
 (function (M) {
     M.v;
 })(M = exports.M || (exports.M = {}));
diff --git a/tests/baselines/reference/nameCollision.js b/tests/baselines/reference/nameCollision.js
index 4f41bf4a086..e51bd5e7c69 100644
--- a/tests/baselines/reference/nameCollision.js
+++ b/tests/baselines/reference/nameCollision.js
@@ -58,7 +58,6 @@ var B;
 (function (B) {
     var A = 12;
 })(B || (B = {}));
-var B;
 (function (B_1) {
     // re-opened module with colliding name
     // this should add an underscore.
diff --git a/tests/baselines/reference/nameCollisionWithBlockScopedVariable1.js b/tests/baselines/reference/nameCollisionWithBlockScopedVariable1.js
index 6a7041a6733..a13c38cf737 100644
--- a/tests/baselines/reference/nameCollisionWithBlockScopedVariable1.js
+++ b/tests/baselines/reference/nameCollisionWithBlockScopedVariable1.js
@@ -16,7 +16,6 @@ var M;
     }
     M.C = C;
 })(M || (M = {}));
-var M;
 (function (M_1) {
     {
         let M = 0;
diff --git a/tests/baselines/reference/nonExportedElementsOfMergedModules.js b/tests/baselines/reference/nonExportedElementsOfMergedModules.js
index e46bf62c05f..623d8b0036e 100644
--- a/tests/baselines/reference/nonExportedElementsOfMergedModules.js
+++ b/tests/baselines/reference/nonExportedElementsOfMergedModules.js
@@ -27,7 +27,6 @@ var One;
     (function (B) {
     })(B || (B = {}));
 })(One || (One = {}));
-var One;
 (function (One) {
     var A;
     (function (A) {
diff --git a/tests/baselines/reference/nullIsSubtypeOfEverythingButUndefined.js b/tests/baselines/reference/nullIsSubtypeOfEverythingButUndefined.js
index d285818aaa9..905ea763d56 100644
--- a/tests/baselines/reference/nullIsSubtypeOfEverythingButUndefined.js
+++ b/tests/baselines/reference/nullIsSubtypeOfEverythingButUndefined.js
@@ -142,7 +142,6 @@ var r13 = true ? null : E;
 var r14 = true ? E.A : null;
 var r14 = true ? null : E.A;
 function f() { }
-var f;
 (function (f) {
     f.bar = 1;
 })(f || (f = {}));
@@ -154,7 +153,6 @@ var c = (function () {
     }
     return c;
 }());
-var c;
 (function (c) {
     c.bar = 1;
 })(c || (c = {}));
diff --git a/tests/baselines/reference/objectLiteralShorthandPropertiesWithModule.js b/tests/baselines/reference/objectLiteralShorthandPropertiesWithModule.js
index 83dd0210a4c..69395b0df49 100644
--- a/tests/baselines/reference/objectLiteralShorthandPropertiesWithModule.js
+++ b/tests/baselines/reference/objectLiteralShorthandPropertiesWithModule.js
@@ -19,7 +19,6 @@ module m {
 var m;
 (function (m) {
 })(m || (m = {}));
-var m;
 (function (m) {
     var z = m.x;
     var y = {
diff --git a/tests/baselines/reference/objectLiteralShorthandPropertiesWithModuleES6.js b/tests/baselines/reference/objectLiteralShorthandPropertiesWithModuleES6.js
index 7a5aaa34242..c9d7edf8140 100644
--- a/tests/baselines/reference/objectLiteralShorthandPropertiesWithModuleES6.js
+++ b/tests/baselines/reference/objectLiteralShorthandPropertiesWithModuleES6.js
@@ -17,7 +17,6 @@ module m {
 var m;
 (function (m) {
 })(m || (m = {}));
-var m;
 (function (m) {
     var z = m.x;
     var y = {
diff --git a/tests/baselines/reference/parserEnumDeclaration4.js b/tests/baselines/reference/parserEnumDeclaration4.js
index 47450d419e1..d5b1e696a3d 100644
--- a/tests/baselines/reference/parserEnumDeclaration4.js
+++ b/tests/baselines/reference/parserEnumDeclaration4.js
@@ -3,7 +3,6 @@ enum void {
 }
 
 //// [parserEnumDeclaration4.js]
-var ;
 (function () {
 })( || ( = {}));
 void {};
diff --git a/tests/baselines/reference/privacyCheckAnonymousFunctionParameter2.js b/tests/baselines/reference/privacyCheckAnonymousFunctionParameter2.js
index 9965f472d75..1da2ec03ed7 100644
--- a/tests/baselines/reference/privacyCheckAnonymousFunctionParameter2.js
+++ b/tests/baselines/reference/privacyCheckAnonymousFunctionParameter2.js
@@ -25,7 +25,6 @@ define(["require", "exports"], function (require, exports) {
         }
         Q.foo = foo;
     })(Q || (Q = {}));
-    var Q;
     (function (Q) {
         function bar() {
             Q.foo(null);
diff --git a/tests/baselines/reference/privacyCheckExportAssignmentOnExportedGenericInterface2.js b/tests/baselines/reference/privacyCheckExportAssignmentOnExportedGenericInterface2.js
index cb61a823990..c2f88dc08f5 100644
--- a/tests/baselines/reference/privacyCheckExportAssignmentOnExportedGenericInterface2.js
+++ b/tests/baselines/reference/privacyCheckExportAssignmentOnExportedGenericInterface2.js
@@ -19,7 +19,6 @@ define(["require", "exports"], function (require, exports) {
     function Foo(array) {
         return undefined;
     }
-    var Foo;
     (function (Foo) {
         Foo.x = "hello";
     })(Foo || (Foo = {}));
diff --git a/tests/baselines/reference/privacyImport.js b/tests/baselines/reference/privacyImport.js
index fcac37bac36..2915b6e5f24 100644
--- a/tests/baselines/reference/privacyImport.js
+++ b/tests/baselines/reference/privacyImport.js
@@ -684,7 +684,6 @@ exports.glo_im2_public = glo_M3_private;
 //    module "abc3" {
 //    }
 //}
-var m2;
 (function (m2) {
     //import m3 = require("use_glo_M1_public");
     var m4;
diff --git a/tests/baselines/reference/privacyImportParseErrors.js b/tests/baselines/reference/privacyImportParseErrors.js
index 369f9f109af..b705bbe1170 100644
--- a/tests/baselines/reference/privacyImportParseErrors.js
+++ b/tests/baselines/reference/privacyImportParseErrors.js
@@ -562,7 +562,6 @@ exports.glo_im1_public = glo_M1_public;
 exports.glo_im2_public = glo_M3_private;
 exports.glo_im3_public = require("glo_M2_public");
 exports.glo_im4_public = require("glo_M4_private");
-var m2;
 (function (m2_1) {
     var m4;
     (function (m4) {
diff --git a/tests/baselines/reference/privateStaticNotAccessibleInClodule.js b/tests/baselines/reference/privateStaticNotAccessibleInClodule.js
index cb67a15fb24..8405eb112e2 100644
--- a/tests/baselines/reference/privateStaticNotAccessibleInClodule.js
+++ b/tests/baselines/reference/privateStaticNotAccessibleInClodule.js
@@ -17,7 +17,6 @@ var C = (function () {
     }
     return C;
 }());
-var C;
 (function (C) {
     C.y = C.bar; // error
 })(C || (C = {}));
diff --git a/tests/baselines/reference/privateStaticNotAccessibleInClodule2.js b/tests/baselines/reference/privateStaticNotAccessibleInClodule2.js
index 7ed6f3d6792..31473f5dc4f 100644
--- a/tests/baselines/reference/privateStaticNotAccessibleInClodule2.js
+++ b/tests/baselines/reference/privateStaticNotAccessibleInClodule2.js
@@ -33,7 +33,6 @@ var D = (function (_super) {
     }
     return D;
 }(C));
-var D;
 (function (D) {
     D.y = D.bar; // error
 })(D || (D = {}));
diff --git a/tests/baselines/reference/protectedStaticNotAccessibleInClodule.js b/tests/baselines/reference/protectedStaticNotAccessibleInClodule.js
index 91776654692..a1411938405 100644
--- a/tests/baselines/reference/protectedStaticNotAccessibleInClodule.js
+++ b/tests/baselines/reference/protectedStaticNotAccessibleInClodule.js
@@ -18,7 +18,6 @@ var C = (function () {
     }
     return C;
 }());
-var C;
 (function (C) {
     C.f = C.foo; // OK
     C.b = C.bar; // error
diff --git a/tests/baselines/reference/qualify.js b/tests/baselines/reference/qualify.js
index ffb643b8ea4..a1e28bd9dc1 100644
--- a/tests/baselines/reference/qualify.js
+++ b/tests/baselines/reference/qualify.js
@@ -69,7 +69,6 @@ var M;
         N.n = 1;
     })(N = M.N || (M.N = {}));
 })(M || (M = {}));
-var M;
 (function (M) {
     var N;
     (function (N) {
diff --git a/tests/baselines/reference/recursiveClassReferenceTest.js b/tests/baselines/reference/recursiveClassReferenceTest.js
index 3aa066d158d..2498763cde9 100644
--- a/tests/baselines/reference/recursiveClassReferenceTest.js
+++ b/tests/baselines/reference/recursiveClassReferenceTest.js
@@ -132,7 +132,6 @@ var Sample;
         })(Thing = Actions.Thing || (Actions.Thing = {}));
     })(Actions = Sample.Actions || (Sample.Actions = {}));
 })(Sample || (Sample = {}));
-var Sample;
 (function (Sample) {
     var Thing;
     (function (Thing) {
@@ -165,7 +164,6 @@ var AbstractMode = (function () {
     AbstractMode.prototype.getInitialState = function () { return null; };
     return AbstractMode;
 }());
-var Sample;
 (function (Sample) {
     var Thing;
     (function (Thing) {
diff --git a/tests/baselines/reference/recursiveClassReferenceTest.js.map b/tests/baselines/reference/recursiveClassReferenceTest.js.map
index 7e0b27b82b4..2424983652f 100644
--- a/tests/baselines/reference/recursiveClassReferenceTest.js.map
+++ b/tests/baselines/reference/recursiveClassReferenceTest.js.map
@@ -1,2 +1,2 @@
 //// [recursiveClassReferenceTest.js.map]
-{"version":3,"file":"recursiveClassReferenceTest.js","sourceRoot":"","sources":["recursiveClassReferenceTest.ts"],"names":[],"mappings":"AAAA,iEAAiE;AACjE,0EAA0E;;;;;;AA8B1E,IAAO,MAAM,CAUZ;AAVD,WAAO,MAAM;IAAC,IAAA,OAAO,CAUpB;IAVa,WAAA,OAAO;QAAC,IAAA,KAAK,CAU1B;QAVqB,WAAA,OAAK;YAAC,IAAA,IAAI,CAU/B;YAV2B,WAAA,IAAI;gBAC/B;oBAAA;oBAQA,CAAC;oBANO,+BAAK,GAAZ,cAAiB,MAAM,CAAC,IAAI,CAAC,CAAC,CAAC;oBAExB,6BAAG,GAAV,UAAW,KAA6B;wBAEvC,MAAM,CAAC,IAAI,CAAC;oBACb,CAAC;oBACF,sBAAC;gBAAD,CAAC,AARD,IAQC;gBARY,oBAAe,kBAQ3B,CAAA;YACF,CAAC,EAV2B,IAAI,GAAJ,YAAI,KAAJ,YAAI,QAU/B;QAAD,CAAC,EAVqB,KAAK,GAAL,aAAK,KAAL,aAAK,QAU1B;IAAD,CAAC,EAVa,OAAO,GAAP,cAAO,KAAP,cAAO,QAUpB;AAAD,CAAC,EAVM,MAAM,KAAN,MAAM,QAUZ;AAED,IAAO,MAAM,CAoBZ;AApBD,WAAO,MAAM;IAAC,IAAA,KAAK,CAoBlB;IApBa,WAAA,KAAK;QAAC,IAAA,OAAO,CAoB1B;QApBmB,WAAA,OAAO;YAC1B;gBAKC,oBAAoB,SAAkC;oBAAlC,cAAS,GAAT,SAAS,CAAyB;oBAD9C,YAAO,GAAO,IAAI,CAAC;oBAEvB,aAAa;oBACb,SAAS,CAAC,SAAS,CAAC,WAAW,EAAE,IAAI,CAAC,CAAC;gBAC3C,CAAC;gBANM,wBAAG,GAAV,UAAW,MAAyC,IAAI,EAAE,CAAC,CAAC,IAAI,CAAC,CAAC,CAAC;oBAAA,MAAM,CAAC,MAAM,CAAC,IAAI,CAAC,CAAC;gBAAA,CAAC,CAAA,CAAC;gBAQlF,+BAAU,GAAjB;oBACC,MAAM,CAAC,OAAO,CAAC;gBAChB,CAAC;gBAEM,4BAAO,GAAd;gBAEA,CAAC;gBAEF,iBAAC;YAAD,CAAC,AAlBD,IAkBC;YAlBY,kBAAU,aAkBtB,CAAA;QACF,CAAC,EApBmB,OAAO,GAAP,aAAO,KAAP,aAAO,QAoB1B;IAAD,CAAC,EApBa,KAAK,GAAL,YAAK,KAAL,YAAK,QAoBlB;AAAD,CAAC,EApBM,MAAM,KAAN,MAAM,QAoBZ;AAGD;IAAA;IAAuF,CAAC;IAA3C,sCAAe,GAAtB,cAAmC,MAAM,CAAC,IAAI,CAAC,CAAA,CAAC;IAAC,mBAAC;AAAD,CAAC,AAAxF,IAAwF;AASxF,IAAO,MAAM,CAwBZ;AAxBD,WAAO,MAAM;IAAC,IAAA,KAAK,CAwBlB;IAxBa,WAAA,KAAK;QAAC,IAAA,SAAS,CAwB5B;QAxBmB,WAAA,SAAS;YAAC,IAAA,SAAS,CAwBtC;YAxB6B,WAAA,SAAS;gBAEtC;oBACO,eAAoB,IAAW;wBAAX,SAAI,GAAJ,IAAI,CAAO;oBAAI,CAAC;oBACnC,qBAAK,GAAZ;wBACC,MAAM,CAAC,IAAI,CAAC;oBACb,CAAC;oBAEM,sBAAM,GAAb,UAAc,KAAY;wBACzB,MAAM,CAAC,IAAI,KAAK,KAAK,CAAC;oBACvB,CAAC;oBAEM,uBAAO,GAAd,cAA0B,MAAM,CAAC,IAAI,CAAC,CAAC,CAAC;oBACzC,YAAC;gBAAD,CAAC,AAXD,IAWC;gBAXY,eAAK,QAWjB,CAAA;gBAED;oBAA0B,wBAAY;oBAAtC;wBAA0B,8BAAY;oBAQtC,CAAC;oBANA,aAAa;oBACN,8BAAe,GAAtB;wBACC,MAAM,CAAC,IAAI,KAAK,CAAC,IAAI,CAAC,CAAC;oBACxB,CAAC;oBAGF,WAAC;gBAAD,CAAC,AARD,CAA0B,YAAY,GAQrC;gBARY,cAAI,OAQhB,CAAA;YACF,CAAC,EAxB6B,SAAS,GAAT,mBAAS,KAAT,mBAAS,QAwBtC;QAAD,CAAC,EAxBmB,SAAS,GAAT,eAAS,KAAT,eAAS,QAwB5B;IAAD,CAAC,EAxBa,KAAK,GAAL,YAAK,KAAL,YAAK,QAwBlB;AAAD,CAAC,EAxBM,MAAM,KAAN,MAAM,QAwBZ"}
\ No newline at end of file
+{"version":3,"file":"recursiveClassReferenceTest.js","sourceRoot":"","sources":["recursiveClassReferenceTest.ts"],"names":[],"mappings":"AAAA,iEAAiE;AACjE,0EAA0E;;;;;;AA8B1E,IAAO,MAAM,CAUZ;AAVD,WAAO,MAAM;IAAC,IAAA,OAAO,CAUpB;IAVa,WAAA,OAAO;QAAC,IAAA,KAAK,CAU1B;QAVqB,WAAA,OAAK;YAAC,IAAA,IAAI,CAU/B;YAV2B,WAAA,IAAI;gBAC/B;oBAAA;oBAQA,CAAC;oBANO,+BAAK,GAAZ,cAAiB,MAAM,CAAC,IAAI,CAAC,CAAC,CAAC;oBAExB,6BAAG,GAAV,UAAW,KAA6B;wBAEvC,MAAM,CAAC,IAAI,CAAC;oBACb,CAAC;oBACF,sBAAC;gBAAD,CAAC,AARD,IAQC;gBARY,oBAAe,kBAQ3B,CAAA;YACF,CAAC,EAV2B,IAAI,GAAJ,YAAI,KAAJ,YAAI,QAU/B;QAAD,CAAC,EAVqB,KAAK,GAAL,aAAK,KAAL,aAAK,QAU1B;IAAD,CAAC,EAVa,OAAO,GAAP,cAAO,KAAP,cAAO,QAUpB;AAAD,CAAC,EAVM,MAAM,KAAN,MAAM,QAUZ;AAED,WAAO,MAAM;IAAC,IAAA,KAAK,CAoBlB;IApBa,WAAA,KAAK;QAAC,IAAA,OAAO,CAoB1B;QApBmB,WAAA,OAAO;YAC1B;gBAKC,oBAAoB,SAAkC;oBAAlC,cAAS,GAAT,SAAS,CAAyB;oBAD9C,YAAO,GAAO,IAAI,CAAC;oBAEvB,aAAa;oBACb,SAAS,CAAC,SAAS,CAAC,WAAW,EAAE,IAAI,CAAC,CAAC;gBAC3C,CAAC;gBANM,wBAAG,GAAV,UAAW,MAAyC,IAAI,EAAE,CAAC,CAAC,IAAI,CAAC,CAAC,CAAC;oBAAA,MAAM,CAAC,MAAM,CAAC,IAAI,CAAC,CAAC;gBAAA,CAAC,CAAA,CAAC;gBAQlF,+BAAU,GAAjB;oBACC,MAAM,CAAC,OAAO,CAAC;gBAChB,CAAC;gBAEM,4BAAO,GAAd;gBAEA,CAAC;gBAEF,iBAAC;YAAD,CAAC,AAlBD,IAkBC;YAlBY,kBAAU,aAkBtB,CAAA;QACF,CAAC,EApBmB,OAAO,GAAP,aAAO,KAAP,aAAO,QAoB1B;IAAD,CAAC,EApBa,KAAK,GAAL,YAAK,KAAL,YAAK,QAoBlB;AAAD,CAAC,EApBM,MAAM,KAAN,MAAM,QAoBZ;AAGD;IAAA;IAAuF,CAAC;IAA3C,sCAAe,GAAtB,cAAmC,MAAM,CAAC,IAAI,CAAC,CAAA,CAAC;IAAC,mBAAC;AAAD,CAAC,AAAxF,IAAwF;AASxF,WAAO,MAAM;IAAC,IAAA,KAAK,CAwBlB;IAxBa,WAAA,KAAK;QAAC,IAAA,SAAS,CAwB5B;QAxBmB,WAAA,SAAS;YAAC,IAAA,SAAS,CAwBtC;YAxB6B,WAAA,SAAS;gBAEtC;oBACO,eAAoB,IAAW;wBAAX,SAAI,GAAJ,IAAI,CAAO;oBAAI,CAAC;oBACnC,qBAAK,GAAZ;wBACC,MAAM,CAAC,IAAI,CAAC;oBACb,CAAC;oBAEM,sBAAM,GAAb,UAAc,KAAY;wBACzB,MAAM,CAAC,IAAI,KAAK,KAAK,CAAC;oBACvB,CAAC;oBAEM,uBAAO,GAAd,cAA0B,MAAM,CAAC,IAAI,CAAC,CAAC,CAAC;oBACzC,YAAC;gBAAD,CAAC,AAXD,IAWC;gBAXY,eAAK,QAWjB,CAAA;gBAED;oBAA0B,wBAAY;oBAAtC;wBAA0B,8BAAY;oBAQtC,CAAC;oBANA,aAAa;oBACN,8BAAe,GAAtB;wBACC,MAAM,CAAC,IAAI,KAAK,CAAC,IAAI,CAAC,CAAC;oBACxB,CAAC;oBAGF,WAAC;gBAAD,CAAC,AARD,CAA0B,YAAY,GAQrC;gBARY,cAAI,OAQhB,CAAA;YACF,CAAC,EAxB6B,SAAS,GAAT,mBAAS,KAAT,mBAAS,QAwBtC;QAAD,CAAC,EAxBmB,SAAS,GAAT,eAAS,KAAT,eAAS,QAwB5B;IAAD,CAAC,EAxBa,KAAK,GAAL,YAAK,KAAL,YAAK,QAwBlB;AAAD,CAAC,EAxBM,MAAM,KAAN,MAAM,QAwBZ"}
\ No newline at end of file
diff --git a/tests/baselines/reference/recursiveClassReferenceTest.sourcemap.txt b/tests/baselines/reference/recursiveClassReferenceTest.sourcemap.txt
index 7e9da7dddf3..e77da96e92a 100644
--- a/tests/baselines/reference/recursiveClassReferenceTest.sourcemap.txt
+++ b/tests/baselines/reference/recursiveClassReferenceTest.sourcemap.txt
@@ -523,53 +523,18 @@ sourceFile:recursiveClassReferenceTest.ts
 6 >Emitted(29, 21) Source(32, 14) + SourceIndex(0)
 7 >Emitted(29, 29) Source(42, 2) + SourceIndex(0)
 ---
->>>var Sample;
+>>>(function (Sample) {
 1 >
-2 >^^^^
-3 >    ^^^^^^
-4 >          ^
-5 >           ^^^^^^^^^^->
+2 >^^^^^^^^^^^
+3 >           ^^^^^^
 1 >
   >
   >
 2 >module 
-3 >    Sample
-4 >          .Thing.Widgets {
-  >          	export class FindWidget implements Sample.Thing.IWidget {
-  >          
-  >          		public gar(runner:(widget:Sample.Thing.IWidget)=>any) { if (true) {return runner(this);}}
-  >          			
-  >          		private domNode:any = null;
-  >          		constructor(private codeThing: Sample.Thing.ICodeThing) {
-  >          		    // scenario 1
-  >          		    codeThing.addWidget("addWidget", this);
-  >          		}
-  >          		
-  >          		public getDomNode() {
-  >          			return domNode;
-  >          		}
-  >          		
-  >          		public destroy() {
-  >          
-  >          		}
-  >          
-  >          	}
-  >          }
-1 >Emitted(30, 1) Source(44, 1) + SourceIndex(0)
-2 >Emitted(30, 5) Source(44, 8) + SourceIndex(0)
-3 >Emitted(30, 11) Source(44, 14) + SourceIndex(0)
-4 >Emitted(30, 12) Source(64, 2) + SourceIndex(0)
----
->>>(function (Sample) {
-1->
-2 >^^^^^^^^^^^
-3 >           ^^^^^^
-1->
-2 >module 
 3 >           Sample
-1->Emitted(31, 1) Source(44, 1) + SourceIndex(0)
-2 >Emitted(31, 12) Source(44, 8) + SourceIndex(0)
-3 >Emitted(31, 18) Source(44, 14) + SourceIndex(0)
+1 >Emitted(30, 1) Source(44, 1) + SourceIndex(0)
+2 >Emitted(30, 12) Source(44, 8) + SourceIndex(0)
+3 >Emitted(30, 18) Source(44, 14) + SourceIndex(0)
 ---
 >>>    var Thing;
 1 >^^^^
@@ -601,10 +566,10 @@ sourceFile:recursiveClassReferenceTest.ts
   >             
   >             	}
   >             }
-1 >Emitted(32, 5) Source(44, 15) + SourceIndex(0)
-2 >Emitted(32, 9) Source(44, 15) + SourceIndex(0)
-3 >Emitted(32, 14) Source(44, 20) + SourceIndex(0)
-4 >Emitted(32, 15) Source(64, 2) + SourceIndex(0)
+1 >Emitted(31, 5) Source(44, 15) + SourceIndex(0)
+2 >Emitted(31, 9) Source(44, 15) + SourceIndex(0)
+3 >Emitted(31, 14) Source(44, 20) + SourceIndex(0)
+4 >Emitted(31, 15) Source(64, 2) + SourceIndex(0)
 ---
 >>>    (function (Thing) {
 1->^^^^
@@ -614,9 +579,9 @@ sourceFile:recursiveClassReferenceTest.ts
 1->
 2 >    
 3 >               Thing
-1->Emitted(33, 5) Source(44, 15) + SourceIndex(0)
-2 >Emitted(33, 16) Source(44, 15) + SourceIndex(0)
-3 >Emitted(33, 21) Source(44, 20) + SourceIndex(0)
+1->Emitted(32, 5) Source(44, 15) + SourceIndex(0)
+2 >Emitted(32, 16) Source(44, 15) + SourceIndex(0)
+3 >Emitted(32, 21) Source(44, 20) + SourceIndex(0)
 ---
 >>>        var Widgets;
 1->^^^^^^^^
@@ -648,10 +613,10 @@ sourceFile:recursiveClassReferenceTest.ts
   >                   
   >                   	}
   >                   }
-1->Emitted(34, 9) Source(44, 21) + SourceIndex(0)
-2 >Emitted(34, 13) Source(44, 21) + SourceIndex(0)
-3 >Emitted(34, 20) Source(44, 28) + SourceIndex(0)
-4 >Emitted(34, 21) Source(64, 2) + SourceIndex(0)
+1->Emitted(33, 9) Source(44, 21) + SourceIndex(0)
+2 >Emitted(33, 13) Source(44, 21) + SourceIndex(0)
+3 >Emitted(33, 20) Source(44, 28) + SourceIndex(0)
+4 >Emitted(33, 21) Source(64, 2) + SourceIndex(0)
 ---
 >>>        (function (Widgets) {
 1->^^^^^^^^
@@ -661,16 +626,16 @@ sourceFile:recursiveClassReferenceTest.ts
 1->
 2 >        
 3 >                   Widgets
-1->Emitted(35, 9) Source(44, 21) + SourceIndex(0)
-2 >Emitted(35, 20) Source(44, 21) + SourceIndex(0)
-3 >Emitted(35, 27) Source(44, 28) + SourceIndex(0)
+1->Emitted(34, 9) Source(44, 21) + SourceIndex(0)
+2 >Emitted(34, 20) Source(44, 21) + SourceIndex(0)
+3 >Emitted(34, 27) Source(44, 28) + SourceIndex(0)
 ---
 >>>            var FindWidget = (function () {
 1->^^^^^^^^^^^^
 2 >            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
 1-> {
   >	
-1->Emitted(36, 13) Source(45, 2) + SourceIndex(0)
+1->Emitted(35, 13) Source(45, 2) + SourceIndex(0)
 ---
 >>>                function FindWidget(codeThing) {
 1->^^^^^^^^^^^^^^^^
@@ -685,9 +650,9 @@ sourceFile:recursiveClassReferenceTest.ts
   >		
 2 >                constructor(private 
 3 >                                    codeThing: Sample.Thing.ICodeThing
-1->Emitted(37, 17) Source(50, 3) + SourceIndex(0)
-2 >Emitted(37, 37) Source(50, 23) + SourceIndex(0)
-3 >Emitted(37, 46) Source(50, 57) + SourceIndex(0)
+1->Emitted(36, 17) Source(50, 3) + SourceIndex(0)
+2 >Emitted(36, 37) Source(50, 23) + SourceIndex(0)
+3 >Emitted(36, 46) Source(50, 57) + SourceIndex(0)
 ---
 >>>                    this.codeThing = codeThing;
 1->^^^^^^^^^^^^^^^^^^^^
@@ -700,11 +665,11 @@ sourceFile:recursiveClassReferenceTest.ts
 3 >                                  
 4 >                                     codeThing
 5 >                                              : Sample.Thing.ICodeThing
-1->Emitted(38, 21) Source(50, 23) + SourceIndex(0)
-2 >Emitted(38, 35) Source(50, 32) + SourceIndex(0)
-3 >Emitted(38, 38) Source(50, 23) + SourceIndex(0)
-4 >Emitted(38, 47) Source(50, 32) + SourceIndex(0)
-5 >Emitted(38, 48) Source(50, 57) + SourceIndex(0)
+1->Emitted(37, 21) Source(50, 23) + SourceIndex(0)
+2 >Emitted(37, 35) Source(50, 32) + SourceIndex(0)
+3 >Emitted(37, 38) Source(50, 23) + SourceIndex(0)
+4 >Emitted(37, 47) Source(50, 32) + SourceIndex(0)
+5 >Emitted(37, 48) Source(50, 57) + SourceIndex(0)
 ---
 >>>                    this.domNode = null;
 1 >^^^^^^^^^^^^^^^^^^^^
@@ -717,11 +682,11 @@ sourceFile:recursiveClassReferenceTest.ts
 3 >                                :any = 
 4 >                                   null
 5 >                                       ;
-1 >Emitted(39, 21) Source(49, 11) + SourceIndex(0)
-2 >Emitted(39, 33) Source(49, 18) + SourceIndex(0)
-3 >Emitted(39, 36) Source(49, 25) + SourceIndex(0)
-4 >Emitted(39, 40) Source(49, 29) + SourceIndex(0)
-5 >Emitted(39, 41) Source(49, 30) + SourceIndex(0)
+1 >Emitted(38, 21) Source(49, 11) + SourceIndex(0)
+2 >Emitted(38, 33) Source(49, 18) + SourceIndex(0)
+3 >Emitted(38, 36) Source(49, 25) + SourceIndex(0)
+4 >Emitted(38, 40) Source(49, 29) + SourceIndex(0)
+5 >Emitted(38, 41) Source(49, 30) + SourceIndex(0)
 ---
 >>>                    // scenario 1
 1 >^^^^^^^^^^^^^^^^^^^^
@@ -731,8 +696,8 @@ sourceFile:recursiveClassReferenceTest.ts
   >		constructor(private codeThing: Sample.Thing.ICodeThing) {
   >		    
 2 >                    // scenario 1
-1 >Emitted(40, 21) Source(51, 7) + SourceIndex(0)
-2 >Emitted(40, 34) Source(51, 20) + SourceIndex(0)
+1 >Emitted(39, 21) Source(51, 7) + SourceIndex(0)
+2 >Emitted(39, 34) Source(51, 20) + SourceIndex(0)
 ---
 >>>                    codeThing.addWidget("addWidget", this);
 1->^^^^^^^^^^^^^^^^^^^^
@@ -756,16 +721,16 @@ sourceFile:recursiveClassReferenceTest.ts
 8 >                                                     this
 9 >                                                         )
 10>                                                          ;
-1->Emitted(41, 21) Source(52, 7) + SourceIndex(0)
-2 >Emitted(41, 30) Source(52, 16) + SourceIndex(0)
-3 >Emitted(41, 31) Source(52, 17) + SourceIndex(0)
-4 >Emitted(41, 40) Source(52, 26) + SourceIndex(0)
-5 >Emitted(41, 41) Source(52, 27) + SourceIndex(0)
-6 >Emitted(41, 52) Source(52, 38) + SourceIndex(0)
-7 >Emitted(41, 54) Source(52, 40) + SourceIndex(0)
-8 >Emitted(41, 58) Source(52, 44) + SourceIndex(0)
-9 >Emitted(41, 59) Source(52, 45) + SourceIndex(0)
-10>Emitted(41, 60) Source(52, 46) + SourceIndex(0)
+1->Emitted(40, 21) Source(52, 7) + SourceIndex(0)
+2 >Emitted(40, 30) Source(52, 16) + SourceIndex(0)
+3 >Emitted(40, 31) Source(52, 17) + SourceIndex(0)
+4 >Emitted(40, 40) Source(52, 26) + SourceIndex(0)
+5 >Emitted(40, 41) Source(52, 27) + SourceIndex(0)
+6 >Emitted(40, 52) Source(52, 38) + SourceIndex(0)
+7 >Emitted(40, 54) Source(52, 40) + SourceIndex(0)
+8 >Emitted(40, 58) Source(52, 44) + SourceIndex(0)
+9 >Emitted(40, 59) Source(52, 45) + SourceIndex(0)
+10>Emitted(40, 60) Source(52, 46) + SourceIndex(0)
 ---
 >>>                }
 1 >^^^^^^^^^^^^^^^^
@@ -774,8 +739,8 @@ sourceFile:recursiveClassReferenceTest.ts
 1 >
   >		
 2 >                }
-1 >Emitted(42, 17) Source(53, 3) + SourceIndex(0)
-2 >Emitted(42, 18) Source(53, 4) + SourceIndex(0)
+1 >Emitted(41, 17) Source(53, 3) + SourceIndex(0)
+2 >Emitted(41, 18) Source(53, 4) + SourceIndex(0)
 ---
 >>>                FindWidget.prototype.gar = function (runner) { if (true) {
 1->^^^^^^^^^^^^^^^^
@@ -804,19 +769,19 @@ sourceFile:recursiveClassReferenceTest.ts
 11>                                                                       )
 12>                                                                         
 13>                                                                         {
-1->Emitted(43, 17) Source(47, 10) + SourceIndex(0)
-2 >Emitted(43, 41) Source(47, 13) + SourceIndex(0)
-3 >Emitted(43, 44) Source(47, 3) + SourceIndex(0)
-4 >Emitted(43, 54) Source(47, 14) + SourceIndex(0)
-5 >Emitted(43, 60) Source(47, 55) + SourceIndex(0)
-6 >Emitted(43, 64) Source(47, 59) + SourceIndex(0)
-7 >Emitted(43, 66) Source(47, 61) + SourceIndex(0)
-8 >Emitted(43, 67) Source(47, 62) + SourceIndex(0)
-9 >Emitted(43, 68) Source(47, 63) + SourceIndex(0)
-10>Emitted(43, 72) Source(47, 67) + SourceIndex(0)
-11>Emitted(43, 73) Source(47, 68) + SourceIndex(0)
-12>Emitted(43, 74) Source(47, 69) + SourceIndex(0)
-13>Emitted(43, 75) Source(47, 70) + SourceIndex(0)
+1->Emitted(42, 17) Source(47, 10) + SourceIndex(0)
+2 >Emitted(42, 41) Source(47, 13) + SourceIndex(0)
+3 >Emitted(42, 44) Source(47, 3) + SourceIndex(0)
+4 >Emitted(42, 54) Source(47, 14) + SourceIndex(0)
+5 >Emitted(42, 60) Source(47, 55) + SourceIndex(0)
+6 >Emitted(42, 64) Source(47, 59) + SourceIndex(0)
+7 >Emitted(42, 66) Source(47, 61) + SourceIndex(0)
+8 >Emitted(42, 67) Source(47, 62) + SourceIndex(0)
+9 >Emitted(42, 68) Source(47, 63) + SourceIndex(0)
+10>Emitted(42, 72) Source(47, 67) + SourceIndex(0)
+11>Emitted(42, 73) Source(47, 68) + SourceIndex(0)
+12>Emitted(42, 74) Source(47, 69) + SourceIndex(0)
+13>Emitted(42, 75) Source(47, 70) + SourceIndex(0)
 ---
 >>>                    return runner(this);
 1 >^^^^^^^^^^^^^^^^^^^^
@@ -835,14 +800,14 @@ sourceFile:recursiveClassReferenceTest.ts
 6 >                                  this
 7 >                                      )
 8 >                                       ;
-1 >Emitted(44, 21) Source(47, 70) + SourceIndex(0)
-2 >Emitted(44, 27) Source(47, 76) + SourceIndex(0)
-3 >Emitted(44, 28) Source(47, 77) + SourceIndex(0)
-4 >Emitted(44, 34) Source(47, 83) + SourceIndex(0)
-5 >Emitted(44, 35) Source(47, 84) + SourceIndex(0)
-6 >Emitted(44, 39) Source(47, 88) + SourceIndex(0)
-7 >Emitted(44, 40) Source(47, 89) + SourceIndex(0)
-8 >Emitted(44, 41) Source(47, 90) + SourceIndex(0)
+1 >Emitted(43, 21) Source(47, 70) + SourceIndex(0)
+2 >Emitted(43, 27) Source(47, 76) + SourceIndex(0)
+3 >Emitted(43, 28) Source(47, 77) + SourceIndex(0)
+4 >Emitted(43, 34) Source(47, 83) + SourceIndex(0)
+5 >Emitted(43, 35) Source(47, 84) + SourceIndex(0)
+6 >Emitted(43, 39) Source(47, 88) + SourceIndex(0)
+7 >Emitted(43, 40) Source(47, 89) + SourceIndex(0)
+8 >Emitted(43, 41) Source(47, 90) + SourceIndex(0)
 ---
 >>>                } };
 1 >^^^^^^^^^^^^^^^^
@@ -854,10 +819,10 @@ sourceFile:recursiveClassReferenceTest.ts
 2 >                }
 3 >                 
 4 >                  }
-1 >Emitted(45, 17) Source(47, 90) + SourceIndex(0)
-2 >Emitted(45, 18) Source(47, 91) + SourceIndex(0)
-3 >Emitted(45, 19) Source(47, 91) + SourceIndex(0)
-4 >Emitted(45, 20) Source(47, 92) + SourceIndex(0)
+1 >Emitted(44, 17) Source(47, 90) + SourceIndex(0)
+2 >Emitted(44, 18) Source(47, 91) + SourceIndex(0)
+3 >Emitted(44, 19) Source(47, 91) + SourceIndex(0)
+4 >Emitted(44, 20) Source(47, 92) + SourceIndex(0)
 ---
 >>>                FindWidget.prototype.getDomNode = function () {
 1->^^^^^^^^^^^^^^^^
@@ -874,9 +839,9 @@ sourceFile:recursiveClassReferenceTest.ts
   >		public 
 2 >                getDomNode
 3 >                                               
-1->Emitted(46, 17) Source(55, 10) + SourceIndex(0)
-2 >Emitted(46, 48) Source(55, 20) + SourceIndex(0)
-3 >Emitted(46, 51) Source(55, 3) + SourceIndex(0)
+1->Emitted(45, 17) Source(55, 10) + SourceIndex(0)
+2 >Emitted(45, 48) Source(55, 20) + SourceIndex(0)
+3 >Emitted(45, 51) Source(55, 3) + SourceIndex(0)
 ---
 >>>                    return domNode;
 1 >^^^^^^^^^^^^^^^^^^^^
@@ -890,11 +855,11 @@ sourceFile:recursiveClassReferenceTest.ts
 3 >                           
 4 >                           domNode
 5 >                                  ;
-1 >Emitted(47, 21) Source(56, 4) + SourceIndex(0)
-2 >Emitted(47, 27) Source(56, 10) + SourceIndex(0)
-3 >Emitted(47, 28) Source(56, 11) + SourceIndex(0)
-4 >Emitted(47, 35) Source(56, 18) + SourceIndex(0)
-5 >Emitted(47, 36) Source(56, 19) + SourceIndex(0)
+1 >Emitted(46, 21) Source(56, 4) + SourceIndex(0)
+2 >Emitted(46, 27) Source(56, 10) + SourceIndex(0)
+3 >Emitted(46, 28) Source(56, 11) + SourceIndex(0)
+4 >Emitted(46, 35) Source(56, 18) + SourceIndex(0)
+5 >Emitted(46, 36) Source(56, 19) + SourceIndex(0)
 ---
 >>>                };
 1 >^^^^^^^^^^^^^^^^
@@ -903,8 +868,8 @@ sourceFile:recursiveClassReferenceTest.ts
 1 >
   >		
 2 >                }
-1 >Emitted(48, 17) Source(57, 3) + SourceIndex(0)
-2 >Emitted(48, 18) Source(57, 4) + SourceIndex(0)
+1 >Emitted(47, 17) Source(57, 3) + SourceIndex(0)
+2 >Emitted(47, 18) Source(57, 4) + SourceIndex(0)
 ---
 >>>                FindWidget.prototype.destroy = function () {
 1->^^^^^^^^^^^^^^^^
@@ -915,9 +880,9 @@ sourceFile:recursiveClassReferenceTest.ts
   >		public 
 2 >                destroy
 3 >                                            
-1->Emitted(49, 17) Source(59, 10) + SourceIndex(0)
-2 >Emitted(49, 45) Source(59, 17) + SourceIndex(0)
-3 >Emitted(49, 48) Source(59, 3) + SourceIndex(0)
+1->Emitted(48, 17) Source(59, 10) + SourceIndex(0)
+2 >Emitted(48, 45) Source(59, 17) + SourceIndex(0)
+3 >Emitted(48, 48) Source(59, 3) + SourceIndex(0)
 ---
 >>>                };
 1 >^^^^^^^^^^^^^^^^
@@ -927,8 +892,8 @@ sourceFile:recursiveClassReferenceTest.ts
   >
   >		
 2 >                }
-1 >Emitted(50, 17) Source(61, 3) + SourceIndex(0)
-2 >Emitted(50, 18) Source(61, 4) + SourceIndex(0)
+1 >Emitted(49, 17) Source(61, 3) + SourceIndex(0)
+2 >Emitted(49, 18) Source(61, 4) + SourceIndex(0)
 ---
 >>>                return FindWidget;
 1->^^^^^^^^^^^^^^^^
@@ -937,8 +902,8 @@ sourceFile:recursiveClassReferenceTest.ts
   >
   >	
 2 >                }
-1->Emitted(51, 17) Source(63, 2) + SourceIndex(0)
-2 >Emitted(51, 34) Source(63, 3) + SourceIndex(0)
+1->Emitted(50, 17) Source(63, 2) + SourceIndex(0)
+2 >Emitted(50, 34) Source(63, 3) + SourceIndex(0)
 ---
 >>>            }());
 1 >^^^^^^^^^^^^
@@ -968,10 +933,10 @@ sourceFile:recursiveClassReferenceTest.ts
   >             		}
   >             
   >             	}
-1 >Emitted(52, 13) Source(63, 2) + SourceIndex(0)
-2 >Emitted(52, 14) Source(63, 3) + SourceIndex(0)
-3 >Emitted(52, 14) Source(45, 2) + SourceIndex(0)
-4 >Emitted(52, 18) Source(63, 3) + SourceIndex(0)
+1 >Emitted(51, 13) Source(63, 2) + SourceIndex(0)
+2 >Emitted(51, 14) Source(63, 3) + SourceIndex(0)
+3 >Emitted(51, 14) Source(45, 2) + SourceIndex(0)
+4 >Emitted(51, 18) Source(63, 3) + SourceIndex(0)
 ---
 >>>            Widgets.FindWidget = FindWidget;
 1->^^^^^^^^^^^^
@@ -1001,10 +966,10 @@ sourceFile:recursiveClassReferenceTest.ts
   >                              
   >                              	}
 4 >                                           
-1->Emitted(53, 13) Source(45, 15) + SourceIndex(0)
-2 >Emitted(53, 31) Source(45, 25) + SourceIndex(0)
-3 >Emitted(53, 44) Source(63, 3) + SourceIndex(0)
-4 >Emitted(53, 45) Source(63, 3) + SourceIndex(0)
+1->Emitted(52, 13) Source(45, 15) + SourceIndex(0)
+2 >Emitted(52, 31) Source(45, 25) + SourceIndex(0)
+3 >Emitted(52, 44) Source(63, 3) + SourceIndex(0)
+4 >Emitted(52, 45) Source(63, 3) + SourceIndex(0)
 ---
 >>>        })(Widgets = Thing.Widgets || (Thing.Widgets = {}));
 1->^^^^^^^^
@@ -1046,15 +1011,15 @@ sourceFile:recursiveClassReferenceTest.ts
   >                                                    
   >                                                    	}
   >                                                    }
-1->Emitted(54, 9) Source(64, 1) + SourceIndex(0)
-2 >Emitted(54, 10) Source(64, 2) + SourceIndex(0)
-3 >Emitted(54, 12) Source(44, 21) + SourceIndex(0)
-4 >Emitted(54, 19) Source(44, 28) + SourceIndex(0)
-5 >Emitted(54, 22) Source(44, 21) + SourceIndex(0)
-6 >Emitted(54, 35) Source(44, 28) + SourceIndex(0)
-7 >Emitted(54, 40) Source(44, 21) + SourceIndex(0)
-8 >Emitted(54, 53) Source(44, 28) + SourceIndex(0)
-9 >Emitted(54, 61) Source(64, 2) + SourceIndex(0)
+1->Emitted(53, 9) Source(64, 1) + SourceIndex(0)
+2 >Emitted(53, 10) Source(64, 2) + SourceIndex(0)
+3 >Emitted(53, 12) Source(44, 21) + SourceIndex(0)
+4 >Emitted(53, 19) Source(44, 28) + SourceIndex(0)
+5 >Emitted(53, 22) Source(44, 21) + SourceIndex(0)
+6 >Emitted(53, 35) Source(44, 28) + SourceIndex(0)
+7 >Emitted(53, 40) Source(44, 21) + SourceIndex(0)
+8 >Emitted(53, 53) Source(44, 28) + SourceIndex(0)
+9 >Emitted(53, 61) Source(64, 2) + SourceIndex(0)
 ---
 >>>    })(Thing = Sample.Thing || (Sample.Thing = {}));
 1 >^^^^
@@ -1095,15 +1060,15 @@ sourceFile:recursiveClassReferenceTest.ts
   >                                            
   >                                            	}
   >                                            }
-1 >Emitted(55, 5) Source(64, 1) + SourceIndex(0)
-2 >Emitted(55, 6) Source(64, 2) + SourceIndex(0)
-3 >Emitted(55, 8) Source(44, 15) + SourceIndex(0)
-4 >Emitted(55, 13) Source(44, 20) + SourceIndex(0)
-5 >Emitted(55, 16) Source(44, 15) + SourceIndex(0)
-6 >Emitted(55, 28) Source(44, 20) + SourceIndex(0)
-7 >Emitted(55, 33) Source(44, 15) + SourceIndex(0)
-8 >Emitted(55, 45) Source(44, 20) + SourceIndex(0)
-9 >Emitted(55, 53) Source(64, 2) + SourceIndex(0)
+1 >Emitted(54, 5) Source(64, 1) + SourceIndex(0)
+2 >Emitted(54, 6) Source(64, 2) + SourceIndex(0)
+3 >Emitted(54, 8) Source(44, 15) + SourceIndex(0)
+4 >Emitted(54, 13) Source(44, 20) + SourceIndex(0)
+5 >Emitted(54, 16) Source(44, 15) + SourceIndex(0)
+6 >Emitted(54, 28) Source(44, 20) + SourceIndex(0)
+7 >Emitted(54, 33) Source(44, 15) + SourceIndex(0)
+8 >Emitted(54, 45) Source(44, 20) + SourceIndex(0)
+9 >Emitted(54, 53) Source(64, 2) + SourceIndex(0)
 ---
 >>>})(Sample || (Sample = {}));
 1 >
@@ -1141,13 +1106,13 @@ sourceFile:recursiveClassReferenceTest.ts
   >                    
   >                    	}
   >                    }
-1 >Emitted(56, 1) Source(64, 1) + SourceIndex(0)
-2 >Emitted(56, 2) Source(64, 2) + SourceIndex(0)
-3 >Emitted(56, 4) Source(44, 8) + SourceIndex(0)
-4 >Emitted(56, 10) Source(44, 14) + SourceIndex(0)
-5 >Emitted(56, 15) Source(44, 8) + SourceIndex(0)
-6 >Emitted(56, 21) Source(44, 14) + SourceIndex(0)
-7 >Emitted(56, 29) Source(64, 2) + SourceIndex(0)
+1 >Emitted(55, 1) Source(64, 1) + SourceIndex(0)
+2 >Emitted(55, 2) Source(64, 2) + SourceIndex(0)
+3 >Emitted(55, 4) Source(44, 8) + SourceIndex(0)
+4 >Emitted(55, 10) Source(44, 14) + SourceIndex(0)
+5 >Emitted(55, 15) Source(44, 8) + SourceIndex(0)
+6 >Emitted(55, 21) Source(44, 14) + SourceIndex(0)
+7 >Emitted(55, 29) Source(64, 2) + SourceIndex(0)
 ---
 >>>var AbstractMode = (function () {
 1->
@@ -1156,13 +1121,13 @@ sourceFile:recursiveClassReferenceTest.ts
   >
   >interface IMode { getInitialState(): IState;} 
   >
-1->Emitted(57, 1) Source(67, 1) + SourceIndex(0)
+1->Emitted(56, 1) Source(67, 1) + SourceIndex(0)
 ---
 >>>    function AbstractMode() {
 1->^^^^
 2 >    ^^->
 1->
-1->Emitted(58, 5) Source(67, 1) + SourceIndex(0)
+1->Emitted(57, 5) Source(67, 1) + SourceIndex(0)
 ---
 >>>    }
 1->^^^^
@@ -1170,8 +1135,8 @@ sourceFile:recursiveClassReferenceTest.ts
 3 >     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
 1->class AbstractMode implements IMode { public getInitialState(): IState { return null;} 
 2 >    }
-1->Emitted(59, 5) Source(67, 88) + SourceIndex(0)
-2 >Emitted(59, 6) Source(67, 89) + SourceIndex(0)
+1->Emitted(58, 5) Source(67, 88) + SourceIndex(0)
+2 >Emitted(58, 6) Source(67, 89) + SourceIndex(0)
 ---
 >>>    AbstractMode.prototype.getInitialState = function () { return null; };
 1->^^^^
@@ -1194,46 +1159,44 @@ sourceFile:recursiveClassReferenceTest.ts
 8 >                                                                      ;
 9 >                                                                       
 10>                                                                        }
-1->Emitted(60, 5) Source(67, 46) + SourceIndex(0)
-2 >Emitted(60, 43) Source(67, 61) + SourceIndex(0)
-3 >Emitted(60, 46) Source(67, 39) + SourceIndex(0)
-4 >Emitted(60, 60) Source(67, 74) + SourceIndex(0)
-5 >Emitted(60, 66) Source(67, 80) + SourceIndex(0)
-6 >Emitted(60, 67) Source(67, 81) + SourceIndex(0)
-7 >Emitted(60, 71) Source(67, 85) + SourceIndex(0)
-8 >Emitted(60, 72) Source(67, 86) + SourceIndex(0)
-9 >Emitted(60, 73) Source(67, 86) + SourceIndex(0)
-10>Emitted(60, 74) Source(67, 87) + SourceIndex(0)
+1->Emitted(59, 5) Source(67, 46) + SourceIndex(0)
+2 >Emitted(59, 43) Source(67, 61) + SourceIndex(0)
+3 >Emitted(59, 46) Source(67, 39) + SourceIndex(0)
+4 >Emitted(59, 60) Source(67, 74) + SourceIndex(0)
+5 >Emitted(59, 66) Source(67, 80) + SourceIndex(0)
+6 >Emitted(59, 67) Source(67, 81) + SourceIndex(0)
+7 >Emitted(59, 71) Source(67, 85) + SourceIndex(0)
+8 >Emitted(59, 72) Source(67, 86) + SourceIndex(0)
+9 >Emitted(59, 73) Source(67, 86) + SourceIndex(0)
+10>Emitted(59, 74) Source(67, 87) + SourceIndex(0)
 ---
 >>>    return AbstractMode;
 1 >^^^^
 2 >    ^^^^^^^^^^^^^^^^^^^
 1 > 
 2 >    }
-1 >Emitted(61, 5) Source(67, 88) + SourceIndex(0)
-2 >Emitted(61, 24) Source(67, 89) + SourceIndex(0)
+1 >Emitted(60, 5) Source(67, 88) + SourceIndex(0)
+2 >Emitted(60, 24) Source(67, 89) + SourceIndex(0)
 ---
 >>>}());
 1 >
 2 >^
 3 > 
 4 > ^^^^
-5 >     ^^^^^^^->
+5 >     ^^^^^^^^^^^^^^^^->
 1 >
 2 >}
 3 > 
 4 > class AbstractMode implements IMode { public getInitialState(): IState { return null;} }
-1 >Emitted(62, 1) Source(67, 88) + SourceIndex(0)
-2 >Emitted(62, 2) Source(67, 89) + SourceIndex(0)
-3 >Emitted(62, 2) Source(67, 1) + SourceIndex(0)
-4 >Emitted(62, 6) Source(67, 89) + SourceIndex(0)
+1 >Emitted(61, 1) Source(67, 88) + SourceIndex(0)
+2 >Emitted(61, 2) Source(67, 89) + SourceIndex(0)
+3 >Emitted(61, 2) Source(67, 1) + SourceIndex(0)
+4 >Emitted(61, 6) Source(67, 89) + SourceIndex(0)
 ---
->>>var Sample;
+>>>(function (Sample) {
 1->
-2 >^^^^
-3 >    ^^^^^^
-4 >          ^
-5 >           ^^^^^^^^^^->
+2 >^^^^^^^^^^^
+3 >           ^^^^^^
 1->
   >
   >interface IState {}
@@ -1245,47 +1208,10 @@ sourceFile:recursiveClassReferenceTest.ts
   >
   >
 2 >module 
-3 >    Sample
-4 >          .Thing.Languages.PlainText {
-  >          	
-  >          	export class State implements IState {		
-  >                  constructor(private mode: IMode) { }
-  >          		public clone():IState {
-  >          			return this;
-  >          		}
-  >          
-  >          		public equals(other:IState):boolean {
-  >          			return this === other;
-  >          		}
-  >          		
-  >          		public getMode(): IMode { return mode; }
-  >          	}
-  >          	
-  >          	export class Mode extends AbstractMode {
-  >          
-  >          		// scenario 2
-  >          		public getInitialState(): IState {
-  >          			return new State(self);
-  >          		}
-  >          
-  >          
-  >          	}
-  >          }
-1->Emitted(63, 1) Source(76, 1) + SourceIndex(0)
-2 >Emitted(63, 5) Source(76, 8) + SourceIndex(0)
-3 >Emitted(63, 11) Source(76, 14) + SourceIndex(0)
-4 >Emitted(63, 12) Source(100, 2) + SourceIndex(0)
----
->>>(function (Sample) {
-1->
-2 >^^^^^^^^^^^
-3 >           ^^^^^^
-1->
-2 >module 
 3 >           Sample
-1->Emitted(64, 1) Source(76, 1) + SourceIndex(0)
-2 >Emitted(64, 12) Source(76, 8) + SourceIndex(0)
-3 >Emitted(64, 18) Source(76, 14) + SourceIndex(0)
+1->Emitted(62, 1) Source(76, 1) + SourceIndex(0)
+2 >Emitted(62, 12) Source(76, 8) + SourceIndex(0)
+3 >Emitted(62, 18) Source(76, 14) + SourceIndex(0)
 ---
 >>>    var Thing;
 1 >^^^^
@@ -1321,10 +1247,10 @@ sourceFile:recursiveClassReferenceTest.ts
   >             
   >             	}
   >             }
-1 >Emitted(65, 5) Source(76, 15) + SourceIndex(0)
-2 >Emitted(65, 9) Source(76, 15) + SourceIndex(0)
-3 >Emitted(65, 14) Source(76, 20) + SourceIndex(0)
-4 >Emitted(65, 15) Source(100, 2) + SourceIndex(0)
+1 >Emitted(63, 5) Source(76, 15) + SourceIndex(0)
+2 >Emitted(63, 9) Source(76, 15) + SourceIndex(0)
+3 >Emitted(63, 14) Source(76, 20) + SourceIndex(0)
+4 >Emitted(63, 15) Source(100, 2) + SourceIndex(0)
 ---
 >>>    (function (Thing) {
 1->^^^^
@@ -1334,9 +1260,9 @@ sourceFile:recursiveClassReferenceTest.ts
 1->
 2 >    
 3 >               Thing
-1->Emitted(66, 5) Source(76, 15) + SourceIndex(0)
-2 >Emitted(66, 16) Source(76, 15) + SourceIndex(0)
-3 >Emitted(66, 21) Source(76, 20) + SourceIndex(0)
+1->Emitted(64, 5) Source(76, 15) + SourceIndex(0)
+2 >Emitted(64, 16) Source(76, 15) + SourceIndex(0)
+3 >Emitted(64, 21) Source(76, 20) + SourceIndex(0)
 ---
 >>>        var Languages;
 1->^^^^^^^^
@@ -1372,10 +1298,10 @@ sourceFile:recursiveClassReferenceTest.ts
   >                     
   >                     	}
   >                     }
-1->Emitted(67, 9) Source(76, 21) + SourceIndex(0)
-2 >Emitted(67, 13) Source(76, 21) + SourceIndex(0)
-3 >Emitted(67, 22) Source(76, 30) + SourceIndex(0)
-4 >Emitted(67, 23) Source(100, 2) + SourceIndex(0)
+1->Emitted(65, 9) Source(76, 21) + SourceIndex(0)
+2 >Emitted(65, 13) Source(76, 21) + SourceIndex(0)
+3 >Emitted(65, 22) Source(76, 30) + SourceIndex(0)
+4 >Emitted(65, 23) Source(100, 2) + SourceIndex(0)
 ---
 >>>        (function (Languages) {
 1->^^^^^^^^
@@ -1384,9 +1310,9 @@ sourceFile:recursiveClassReferenceTest.ts
 1->
 2 >        
 3 >                   Languages
-1->Emitted(68, 9) Source(76, 21) + SourceIndex(0)
-2 >Emitted(68, 20) Source(76, 21) + SourceIndex(0)
-3 >Emitted(68, 29) Source(76, 30) + SourceIndex(0)
+1->Emitted(66, 9) Source(76, 21) + SourceIndex(0)
+2 >Emitted(66, 20) Source(76, 21) + SourceIndex(0)
+3 >Emitted(66, 29) Source(76, 30) + SourceIndex(0)
 ---
 >>>            var PlainText;
 1 >^^^^^^^^^^^^
@@ -1422,10 +1348,10 @@ sourceFile:recursiveClassReferenceTest.ts
   >                         
   >                         	}
   >                         }
-1 >Emitted(69, 13) Source(76, 31) + SourceIndex(0)
-2 >Emitted(69, 17) Source(76, 31) + SourceIndex(0)
-3 >Emitted(69, 26) Source(76, 40) + SourceIndex(0)
-4 >Emitted(69, 27) Source(100, 2) + SourceIndex(0)
+1 >Emitted(67, 13) Source(76, 31) + SourceIndex(0)
+2 >Emitted(67, 17) Source(76, 31) + SourceIndex(0)
+3 >Emitted(67, 26) Source(76, 40) + SourceIndex(0)
+4 >Emitted(67, 27) Source(100, 2) + SourceIndex(0)
 ---
 >>>            (function (PlainText) {
 1->^^^^^^^^^^^^
@@ -1435,9 +1361,9 @@ sourceFile:recursiveClassReferenceTest.ts
 1->
 2 >            
 3 >                       PlainText
-1->Emitted(70, 13) Source(76, 31) + SourceIndex(0)
-2 >Emitted(70, 24) Source(76, 31) + SourceIndex(0)
-3 >Emitted(70, 33) Source(76, 40) + SourceIndex(0)
+1->Emitted(68, 13) Source(76, 31) + SourceIndex(0)
+2 >Emitted(68, 24) Source(76, 31) + SourceIndex(0)
+3 >Emitted(68, 33) Source(76, 40) + SourceIndex(0)
 ---
 >>>                var State = (function () {
 1->^^^^^^^^^^^^^^^^
@@ -1445,7 +1371,7 @@ sourceFile:recursiveClassReferenceTest.ts
 1-> {
   >	
   >	
-1->Emitted(71, 17) Source(78, 2) + SourceIndex(0)
+1->Emitted(69, 17) Source(78, 2) + SourceIndex(0)
 ---
 >>>                    function State(mode) {
 1->^^^^^^^^^^^^^^^^^^^^
@@ -1456,9 +1382,9 @@ sourceFile:recursiveClassReferenceTest.ts
   >        
 2 >                    constructor(private 
 3 >                                   mode: IMode
-1->Emitted(72, 21) Source(79, 9) + SourceIndex(0)
-2 >Emitted(72, 36) Source(79, 29) + SourceIndex(0)
-3 >Emitted(72, 40) Source(79, 40) + SourceIndex(0)
+1->Emitted(70, 21) Source(79, 9) + SourceIndex(0)
+2 >Emitted(70, 36) Source(79, 29) + SourceIndex(0)
+3 >Emitted(70, 40) Source(79, 40) + SourceIndex(0)
 ---
 >>>                        this.mode = mode;
 1->^^^^^^^^^^^^^^^^^^^^^^^^
@@ -1471,11 +1397,11 @@ sourceFile:recursiveClassReferenceTest.ts
 3 >                                 
 4 >                                    mode
 5 >                                        : IMode
-1->Emitted(73, 25) Source(79, 29) + SourceIndex(0)
-2 >Emitted(73, 34) Source(79, 33) + SourceIndex(0)
-3 >Emitted(73, 37) Source(79, 29) + SourceIndex(0)
-4 >Emitted(73, 41) Source(79, 33) + SourceIndex(0)
-5 >Emitted(73, 42) Source(79, 40) + SourceIndex(0)
+1->Emitted(71, 25) Source(79, 29) + SourceIndex(0)
+2 >Emitted(71, 34) Source(79, 33) + SourceIndex(0)
+3 >Emitted(71, 37) Source(79, 29) + SourceIndex(0)
+4 >Emitted(71, 41) Source(79, 33) + SourceIndex(0)
+5 >Emitted(71, 42) Source(79, 40) + SourceIndex(0)
 ---
 >>>                    }
 1 >^^^^^^^^^^^^^^^^^^^^
@@ -1483,8 +1409,8 @@ sourceFile:recursiveClassReferenceTest.ts
 3 >                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
 1 >) { 
 2 >                    }
-1 >Emitted(74, 21) Source(79, 44) + SourceIndex(0)
-2 >Emitted(74, 22) Source(79, 45) + SourceIndex(0)
+1 >Emitted(72, 21) Source(79, 44) + SourceIndex(0)
+2 >Emitted(72, 22) Source(79, 45) + SourceIndex(0)
 ---
 >>>                    State.prototype.clone = function () {
 1->^^^^^^^^^^^^^^^^^^^^
@@ -1494,9 +1420,9 @@ sourceFile:recursiveClassReferenceTest.ts
   >		public 
 2 >                    clone
 3 >                                         
-1->Emitted(75, 21) Source(80, 10) + SourceIndex(0)
-2 >Emitted(75, 42) Source(80, 15) + SourceIndex(0)
-3 >Emitted(75, 45) Source(80, 3) + SourceIndex(0)
+1->Emitted(73, 21) Source(80, 10) + SourceIndex(0)
+2 >Emitted(73, 42) Source(80, 15) + SourceIndex(0)
+3 >Emitted(73, 45) Source(80, 3) + SourceIndex(0)
 ---
 >>>                        return this;
 1 >^^^^^^^^^^^^^^^^^^^^^^^^
@@ -1510,11 +1436,11 @@ sourceFile:recursiveClassReferenceTest.ts
 3 >                               
 4 >                               this
 5 >                                   ;
-1 >Emitted(76, 25) Source(81, 4) + SourceIndex(0)
-2 >Emitted(76, 31) Source(81, 10) + SourceIndex(0)
-3 >Emitted(76, 32) Source(81, 11) + SourceIndex(0)
-4 >Emitted(76, 36) Source(81, 15) + SourceIndex(0)
-5 >Emitted(76, 37) Source(81, 16) + SourceIndex(0)
+1 >Emitted(74, 25) Source(81, 4) + SourceIndex(0)
+2 >Emitted(74, 31) Source(81, 10) + SourceIndex(0)
+3 >Emitted(74, 32) Source(81, 11) + SourceIndex(0)
+4 >Emitted(74, 36) Source(81, 15) + SourceIndex(0)
+5 >Emitted(74, 37) Source(81, 16) + SourceIndex(0)
 ---
 >>>                    };
 1 >^^^^^^^^^^^^^^^^^^^^
@@ -1523,8 +1449,8 @@ sourceFile:recursiveClassReferenceTest.ts
 1 >
   >		
 2 >                    }
-1 >Emitted(77, 21) Source(82, 3) + SourceIndex(0)
-2 >Emitted(77, 22) Source(82, 4) + SourceIndex(0)
+1 >Emitted(75, 21) Source(82, 3) + SourceIndex(0)
+2 >Emitted(75, 22) Source(82, 4) + SourceIndex(0)
 ---
 >>>                    State.prototype.equals = function (other) {
 1->^^^^^^^^^^^^^^^^^^^^
@@ -1539,11 +1465,11 @@ sourceFile:recursiveClassReferenceTest.ts
 3 >                                          
 4 >                                             public equals(
 5 >                                                       other:IState
-1->Emitted(78, 21) Source(84, 10) + SourceIndex(0)
-2 >Emitted(78, 43) Source(84, 16) + SourceIndex(0)
-3 >Emitted(78, 46) Source(84, 3) + SourceIndex(0)
-4 >Emitted(78, 56) Source(84, 17) + SourceIndex(0)
-5 >Emitted(78, 61) Source(84, 29) + SourceIndex(0)
+1->Emitted(76, 21) Source(84, 10) + SourceIndex(0)
+2 >Emitted(76, 43) Source(84, 16) + SourceIndex(0)
+3 >Emitted(76, 46) Source(84, 3) + SourceIndex(0)
+4 >Emitted(76, 56) Source(84, 17) + SourceIndex(0)
+5 >Emitted(76, 61) Source(84, 29) + SourceIndex(0)
 ---
 >>>                        return this === other;
 1 >^^^^^^^^^^^^^^^^^^^^^^^^
@@ -1561,13 +1487,13 @@ sourceFile:recursiveClassReferenceTest.ts
 5 >                                    === 
 6 >                                        other
 7 >                                             ;
-1 >Emitted(79, 25) Source(85, 4) + SourceIndex(0)
-2 >Emitted(79, 31) Source(85, 10) + SourceIndex(0)
-3 >Emitted(79, 32) Source(85, 11) + SourceIndex(0)
-4 >Emitted(79, 36) Source(85, 15) + SourceIndex(0)
-5 >Emitted(79, 41) Source(85, 20) + SourceIndex(0)
-6 >Emitted(79, 46) Source(85, 25) + SourceIndex(0)
-7 >Emitted(79, 47) Source(85, 26) + SourceIndex(0)
+1 >Emitted(77, 25) Source(85, 4) + SourceIndex(0)
+2 >Emitted(77, 31) Source(85, 10) + SourceIndex(0)
+3 >Emitted(77, 32) Source(85, 11) + SourceIndex(0)
+4 >Emitted(77, 36) Source(85, 15) + SourceIndex(0)
+5 >Emitted(77, 41) Source(85, 20) + SourceIndex(0)
+6 >Emitted(77, 46) Source(85, 25) + SourceIndex(0)
+7 >Emitted(77, 47) Source(85, 26) + SourceIndex(0)
 ---
 >>>                    };
 1 >^^^^^^^^^^^^^^^^^^^^
@@ -1576,8 +1502,8 @@ sourceFile:recursiveClassReferenceTest.ts
 1 >
   >		
 2 >                    }
-1 >Emitted(80, 21) Source(86, 3) + SourceIndex(0)
-2 >Emitted(80, 22) Source(86, 4) + SourceIndex(0)
+1 >Emitted(78, 21) Source(86, 3) + SourceIndex(0)
+2 >Emitted(78, 22) Source(86, 4) + SourceIndex(0)
 ---
 >>>                    State.prototype.getMode = function () { return mode; };
 1->^^^^^^^^^^^^^^^^^^^^
@@ -1602,16 +1528,16 @@ sourceFile:recursiveClassReferenceTest.ts
 8 >                                                                       ;
 9 >                                                                         
 10>                                                                         }
-1->Emitted(81, 21) Source(88, 10) + SourceIndex(0)
-2 >Emitted(81, 44) Source(88, 17) + SourceIndex(0)
-3 >Emitted(81, 47) Source(88, 3) + SourceIndex(0)
-4 >Emitted(81, 61) Source(88, 29) + SourceIndex(0)
-5 >Emitted(81, 67) Source(88, 35) + SourceIndex(0)
-6 >Emitted(81, 68) Source(88, 36) + SourceIndex(0)
-7 >Emitted(81, 72) Source(88, 40) + SourceIndex(0)
-8 >Emitted(81, 73) Source(88, 41) + SourceIndex(0)
-9 >Emitted(81, 74) Source(88, 42) + SourceIndex(0)
-10>Emitted(81, 75) Source(88, 43) + SourceIndex(0)
+1->Emitted(79, 21) Source(88, 10) + SourceIndex(0)
+2 >Emitted(79, 44) Source(88, 17) + SourceIndex(0)
+3 >Emitted(79, 47) Source(88, 3) + SourceIndex(0)
+4 >Emitted(79, 61) Source(88, 29) + SourceIndex(0)
+5 >Emitted(79, 67) Source(88, 35) + SourceIndex(0)
+6 >Emitted(79, 68) Source(88, 36) + SourceIndex(0)
+7 >Emitted(79, 72) Source(88, 40) + SourceIndex(0)
+8 >Emitted(79, 73) Source(88, 41) + SourceIndex(0)
+9 >Emitted(79, 74) Source(88, 42) + SourceIndex(0)
+10>Emitted(79, 75) Source(88, 43) + SourceIndex(0)
 ---
 >>>                    return State;
 1 >^^^^^^^^^^^^^^^^^^^^
@@ -1619,8 +1545,8 @@ sourceFile:recursiveClassReferenceTest.ts
 1 >
   >	
 2 >                    }
-1 >Emitted(82, 21) Source(89, 2) + SourceIndex(0)
-2 >Emitted(82, 33) Source(89, 3) + SourceIndex(0)
+1 >Emitted(80, 21) Source(89, 2) + SourceIndex(0)
+2 >Emitted(80, 33) Source(89, 3) + SourceIndex(0)
 ---
 >>>                }());
 1 >^^^^^^^^^^^^^^^^
@@ -1643,10 +1569,10 @@ sourceFile:recursiveClassReferenceTest.ts
   >                 		
   >                 		public getMode(): IMode { return mode; }
   >                 	}
-1 >Emitted(83, 17) Source(89, 2) + SourceIndex(0)
-2 >Emitted(83, 18) Source(89, 3) + SourceIndex(0)
-3 >Emitted(83, 18) Source(78, 2) + SourceIndex(0)
-4 >Emitted(83, 22) Source(89, 3) + SourceIndex(0)
+1 >Emitted(81, 17) Source(89, 2) + SourceIndex(0)
+2 >Emitted(81, 18) Source(89, 3) + SourceIndex(0)
+3 >Emitted(81, 18) Source(78, 2) + SourceIndex(0)
+4 >Emitted(81, 22) Source(89, 3) + SourceIndex(0)
 ---
 >>>                PlainText.State = State;
 1->^^^^^^^^^^^^^^^^
@@ -1669,10 +1595,10 @@ sourceFile:recursiveClassReferenceTest.ts
   >                               		public getMode(): IMode { return mode; }
   >                               	}
 4 >                                       
-1->Emitted(84, 17) Source(78, 15) + SourceIndex(0)
-2 >Emitted(84, 32) Source(78, 20) + SourceIndex(0)
-3 >Emitted(84, 40) Source(89, 3) + SourceIndex(0)
-4 >Emitted(84, 41) Source(89, 3) + SourceIndex(0)
+1->Emitted(82, 17) Source(78, 15) + SourceIndex(0)
+2 >Emitted(82, 32) Source(78, 20) + SourceIndex(0)
+3 >Emitted(82, 40) Source(89, 3) + SourceIndex(0)
+4 >Emitted(82, 41) Source(89, 3) + SourceIndex(0)
 ---
 >>>                var Mode = (function (_super) {
 1->^^^^^^^^^^^^^^^^
@@ -1680,29 +1606,29 @@ sourceFile:recursiveClassReferenceTest.ts
 1->
   >	
   >	
-1->Emitted(85, 17) Source(91, 2) + SourceIndex(0)
+1->Emitted(83, 17) Source(91, 2) + SourceIndex(0)
 ---
 >>>                    __extends(Mode, _super);
 1->^^^^^^^^^^^^^^^^^^^^
 2 >                    ^^^^^^^^^^^^^^^^^^^^^^^^
 1->export class Mode extends 
 2 >                    AbstractMode
-1->Emitted(86, 21) Source(91, 28) + SourceIndex(0)
-2 >Emitted(86, 45) Source(91, 40) + SourceIndex(0)
+1->Emitted(84, 21) Source(91, 28) + SourceIndex(0)
+2 >Emitted(84, 45) Source(91, 40) + SourceIndex(0)
 ---
 >>>                    function Mode() {
 1 >^^^^^^^^^^^^^^^^^^^^
 2 >                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
 1 >
-1 >Emitted(87, 21) Source(91, 2) + SourceIndex(0)
+1 >Emitted(85, 21) Source(91, 2) + SourceIndex(0)
 ---
 >>>                        _super.apply(this, arguments);
 1->^^^^^^^^^^^^^^^^^^^^^^^^
 2 >                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 1->export class Mode extends 
 2 >                        AbstractMode
-1->Emitted(88, 25) Source(91, 28) + SourceIndex(0)
-2 >Emitted(88, 55) Source(91, 40) + SourceIndex(0)
+1->Emitted(86, 25) Source(91, 28) + SourceIndex(0)
+2 >Emitted(86, 55) Source(91, 40) + SourceIndex(0)
 ---
 >>>                    }
 1 >^^^^^^^^^^^^^^^^^^^^
@@ -1718,8 +1644,8 @@ sourceFile:recursiveClassReferenceTest.ts
   >
   >	
 2 >                    }
-1 >Emitted(89, 21) Source(99, 2) + SourceIndex(0)
-2 >Emitted(89, 22) Source(99, 3) + SourceIndex(0)
+1 >Emitted(87, 21) Source(99, 2) + SourceIndex(0)
+2 >Emitted(87, 22) Source(99, 3) + SourceIndex(0)
 ---
 >>>                    // scenario 2
 1->^^^^^^^^^^^^^^^^^^^^
@@ -1727,8 +1653,8 @@ sourceFile:recursiveClassReferenceTest.ts
 3 >                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
 1->
 2 >                    // scenario 2
-1->Emitted(90, 21) Source(93, 3) + SourceIndex(0)
-2 >Emitted(90, 34) Source(93, 16) + SourceIndex(0)
+1->Emitted(88, 21) Source(93, 3) + SourceIndex(0)
+2 >Emitted(88, 34) Source(93, 16) + SourceIndex(0)
 ---
 >>>                    Mode.prototype.getInitialState = function () {
 1->^^^^^^^^^^^^^^^^^^^^
@@ -1738,9 +1664,9 @@ sourceFile:recursiveClassReferenceTest.ts
   >		public 
 2 >                    getInitialState
 3 >                                                  
-1->Emitted(91, 21) Source(94, 10) + SourceIndex(0)
-2 >Emitted(91, 51) Source(94, 25) + SourceIndex(0)
-3 >Emitted(91, 54) Source(94, 3) + SourceIndex(0)
+1->Emitted(89, 21) Source(94, 10) + SourceIndex(0)
+2 >Emitted(89, 51) Source(94, 25) + SourceIndex(0)
+3 >Emitted(89, 54) Source(94, 3) + SourceIndex(0)
 ---
 >>>                        return new State(self);
 1 >^^^^^^^^^^^^^^^^^^^^^^^^
@@ -1762,15 +1688,15 @@ sourceFile:recursiveClassReferenceTest.ts
 7 >                                         self
 8 >                                             )
 9 >                                              ;
-1 >Emitted(92, 25) Source(95, 4) + SourceIndex(0)
-2 >Emitted(92, 31) Source(95, 10) + SourceIndex(0)
-3 >Emitted(92, 32) Source(95, 11) + SourceIndex(0)
-4 >Emitted(92, 36) Source(95, 15) + SourceIndex(0)
-5 >Emitted(92, 41) Source(95, 20) + SourceIndex(0)
-6 >Emitted(92, 42) Source(95, 21) + SourceIndex(0)
-7 >Emitted(92, 46) Source(95, 25) + SourceIndex(0)
-8 >Emitted(92, 47) Source(95, 26) + SourceIndex(0)
-9 >Emitted(92, 48) Source(95, 27) + SourceIndex(0)
+1 >Emitted(90, 25) Source(95, 4) + SourceIndex(0)
+2 >Emitted(90, 31) Source(95, 10) + SourceIndex(0)
+3 >Emitted(90, 32) Source(95, 11) + SourceIndex(0)
+4 >Emitted(90, 36) Source(95, 15) + SourceIndex(0)
+5 >Emitted(90, 41) Source(95, 20) + SourceIndex(0)
+6 >Emitted(90, 42) Source(95, 21) + SourceIndex(0)
+7 >Emitted(90, 46) Source(95, 25) + SourceIndex(0)
+8 >Emitted(90, 47) Source(95, 26) + SourceIndex(0)
+9 >Emitted(90, 48) Source(95, 27) + SourceIndex(0)
 ---
 >>>                    };
 1 >^^^^^^^^^^^^^^^^^^^^
@@ -1779,8 +1705,8 @@ sourceFile:recursiveClassReferenceTest.ts
 1 >
   >		
 2 >                    }
-1 >Emitted(93, 21) Source(96, 3) + SourceIndex(0)
-2 >Emitted(93, 22) Source(96, 4) + SourceIndex(0)
+1 >Emitted(91, 21) Source(96, 3) + SourceIndex(0)
+2 >Emitted(91, 22) Source(96, 4) + SourceIndex(0)
 ---
 >>>                    return Mode;
 1->^^^^^^^^^^^^^^^^^^^^
@@ -1791,8 +1717,8 @@ sourceFile:recursiveClassReferenceTest.ts
   >
   >	
 2 >                    }
-1->Emitted(94, 21) Source(99, 2) + SourceIndex(0)
-2 >Emitted(94, 32) Source(99, 3) + SourceIndex(0)
+1->Emitted(92, 21) Source(99, 2) + SourceIndex(0)
+2 >Emitted(92, 32) Source(99, 3) + SourceIndex(0)
 ---
 >>>                }(AbstractMode));
 1->^^^^^^^^^^^^^^^^
@@ -1816,12 +1742,12 @@ sourceFile:recursiveClassReferenceTest.ts
   >                              
   >                              
   >                              	}
-1->Emitted(95, 17) Source(99, 2) + SourceIndex(0)
-2 >Emitted(95, 18) Source(99, 3) + SourceIndex(0)
-3 >Emitted(95, 18) Source(91, 2) + SourceIndex(0)
-4 >Emitted(95, 19) Source(91, 28) + SourceIndex(0)
-5 >Emitted(95, 31) Source(91, 40) + SourceIndex(0)
-6 >Emitted(95, 34) Source(99, 3) + SourceIndex(0)
+1->Emitted(93, 17) Source(99, 2) + SourceIndex(0)
+2 >Emitted(93, 18) Source(99, 3) + SourceIndex(0)
+3 >Emitted(93, 18) Source(91, 2) + SourceIndex(0)
+4 >Emitted(93, 19) Source(91, 28) + SourceIndex(0)
+5 >Emitted(93, 31) Source(91, 40) + SourceIndex(0)
+6 >Emitted(93, 34) Source(99, 3) + SourceIndex(0)
 ---
 >>>                PlainText.Mode = Mode;
 1->^^^^^^^^^^^^^^^^
@@ -1841,10 +1767,10 @@ sourceFile:recursiveClassReferenceTest.ts
   >                              
   >                              	}
 4 >                                     
-1->Emitted(96, 17) Source(91, 15) + SourceIndex(0)
-2 >Emitted(96, 31) Source(91, 19) + SourceIndex(0)
-3 >Emitted(96, 38) Source(99, 3) + SourceIndex(0)
-4 >Emitted(96, 39) Source(99, 3) + SourceIndex(0)
+1->Emitted(94, 17) Source(91, 15) + SourceIndex(0)
+2 >Emitted(94, 31) Source(91, 19) + SourceIndex(0)
+3 >Emitted(94, 38) Source(99, 3) + SourceIndex(0)
+4 >Emitted(94, 39) Source(99, 3) + SourceIndex(0)
 ---
 >>>            })(PlainText = Languages.PlainText || (Languages.PlainText = {}));
 1->^^^^^^^^^^^^
@@ -1890,15 +1816,15 @@ sourceFile:recursiveClassReferenceTest.ts
   >                                                                      
   >                                                                      	}
   >                                                                      }
-1->Emitted(97, 13) Source(100, 1) + SourceIndex(0)
-2 >Emitted(97, 14) Source(100, 2) + SourceIndex(0)
-3 >Emitted(97, 16) Source(76, 31) + SourceIndex(0)
-4 >Emitted(97, 25) Source(76, 40) + SourceIndex(0)
-5 >Emitted(97, 28) Source(76, 31) + SourceIndex(0)
-6 >Emitted(97, 47) Source(76, 40) + SourceIndex(0)
-7 >Emitted(97, 52) Source(76, 31) + SourceIndex(0)
-8 >Emitted(97, 71) Source(76, 40) + SourceIndex(0)
-9 >Emitted(97, 79) Source(100, 2) + SourceIndex(0)
+1->Emitted(95, 13) Source(100, 1) + SourceIndex(0)
+2 >Emitted(95, 14) Source(100, 2) + SourceIndex(0)
+3 >Emitted(95, 16) Source(76, 31) + SourceIndex(0)
+4 >Emitted(95, 25) Source(76, 40) + SourceIndex(0)
+5 >Emitted(95, 28) Source(76, 31) + SourceIndex(0)
+6 >Emitted(95, 47) Source(76, 40) + SourceIndex(0)
+7 >Emitted(95, 52) Source(76, 31) + SourceIndex(0)
+8 >Emitted(95, 71) Source(76, 40) + SourceIndex(0)
+9 >Emitted(95, 79) Source(100, 2) + SourceIndex(0)
 ---
 >>>        })(Languages = Thing.Languages || (Thing.Languages = {}));
 1 >^^^^^^^^
@@ -1943,15 +1869,15 @@ sourceFile:recursiveClassReferenceTest.ts
   >                                                          
   >                                                          	}
   >                                                          }
-1 >Emitted(98, 9) Source(100, 1) + SourceIndex(0)
-2 >Emitted(98, 10) Source(100, 2) + SourceIndex(0)
-3 >Emitted(98, 12) Source(76, 21) + SourceIndex(0)
-4 >Emitted(98, 21) Source(76, 30) + SourceIndex(0)
-5 >Emitted(98, 24) Source(76, 21) + SourceIndex(0)
-6 >Emitted(98, 39) Source(76, 30) + SourceIndex(0)
-7 >Emitted(98, 44) Source(76, 21) + SourceIndex(0)
-8 >Emitted(98, 59) Source(76, 30) + SourceIndex(0)
-9 >Emitted(98, 67) Source(100, 2) + SourceIndex(0)
+1 >Emitted(96, 9) Source(100, 1) + SourceIndex(0)
+2 >Emitted(96, 10) Source(100, 2) + SourceIndex(0)
+3 >Emitted(96, 12) Source(76, 21) + SourceIndex(0)
+4 >Emitted(96, 21) Source(76, 30) + SourceIndex(0)
+5 >Emitted(96, 24) Source(76, 21) + SourceIndex(0)
+6 >Emitted(96, 39) Source(76, 30) + SourceIndex(0)
+7 >Emitted(96, 44) Source(76, 21) + SourceIndex(0)
+8 >Emitted(96, 59) Source(76, 30) + SourceIndex(0)
+9 >Emitted(96, 67) Source(100, 2) + SourceIndex(0)
 ---
 >>>    })(Thing = Sample.Thing || (Sample.Thing = {}));
 1 >^^^^
@@ -1996,15 +1922,15 @@ sourceFile:recursiveClassReferenceTest.ts
   >                                            
   >                                            	}
   >                                            }
-1 >Emitted(99, 5) Source(100, 1) + SourceIndex(0)
-2 >Emitted(99, 6) Source(100, 2) + SourceIndex(0)
-3 >Emitted(99, 8) Source(76, 15) + SourceIndex(0)
-4 >Emitted(99, 13) Source(76, 20) + SourceIndex(0)
-5 >Emitted(99, 16) Source(76, 15) + SourceIndex(0)
-6 >Emitted(99, 28) Source(76, 20) + SourceIndex(0)
-7 >Emitted(99, 33) Source(76, 15) + SourceIndex(0)
-8 >Emitted(99, 45) Source(76, 20) + SourceIndex(0)
-9 >Emitted(99, 53) Source(100, 2) + SourceIndex(0)
+1 >Emitted(97, 5) Source(100, 1) + SourceIndex(0)
+2 >Emitted(97, 6) Source(100, 2) + SourceIndex(0)
+3 >Emitted(97, 8) Source(76, 15) + SourceIndex(0)
+4 >Emitted(97, 13) Source(76, 20) + SourceIndex(0)
+5 >Emitted(97, 16) Source(76, 15) + SourceIndex(0)
+6 >Emitted(97, 28) Source(76, 20) + SourceIndex(0)
+7 >Emitted(97, 33) Source(76, 15) + SourceIndex(0)
+8 >Emitted(97, 45) Source(76, 20) + SourceIndex(0)
+9 >Emitted(97, 53) Source(100, 2) + SourceIndex(0)
 ---
 >>>})(Sample || (Sample = {}));
 1 >
@@ -2046,12 +1972,12 @@ sourceFile:recursiveClassReferenceTest.ts
   >                    
   >                    	}
   >                    }
-1 >Emitted(100, 1) Source(100, 1) + SourceIndex(0)
-2 >Emitted(100, 2) Source(100, 2) + SourceIndex(0)
-3 >Emitted(100, 4) Source(76, 8) + SourceIndex(0)
-4 >Emitted(100, 10) Source(76, 14) + SourceIndex(0)
-5 >Emitted(100, 15) Source(76, 8) + SourceIndex(0)
-6 >Emitted(100, 21) Source(76, 14) + SourceIndex(0)
-7 >Emitted(100, 29) Source(100, 2) + SourceIndex(0)
+1 >Emitted(98, 1) Source(100, 1) + SourceIndex(0)
+2 >Emitted(98, 2) Source(100, 2) + SourceIndex(0)
+3 >Emitted(98, 4) Source(76, 8) + SourceIndex(0)
+4 >Emitted(98, 10) Source(76, 14) + SourceIndex(0)
+5 >Emitted(98, 15) Source(76, 8) + SourceIndex(0)
+6 >Emitted(98, 21) Source(76, 14) + SourceIndex(0)
+7 >Emitted(98, 29) Source(100, 2) + SourceIndex(0)
 ---
 >>>//# sourceMappingURL=recursiveClassReferenceTest.js.map
\ No newline at end of file
diff --git a/tests/baselines/reference/recursiveCloduleReference.js b/tests/baselines/reference/recursiveCloduleReference.js
index 07d80e6011a..3d261a4f9ae 100644
--- a/tests/baselines/reference/recursiveCloduleReference.js
+++ b/tests/baselines/reference/recursiveCloduleReference.js
@@ -19,7 +19,6 @@ var M;
         return C;
     }());
     M.C = C;
-    var C;
     (function (C_1) {
         C_1.C = M.C;
     })(C = M.C || (M.C = {}));
diff --git a/tests/baselines/reference/recursiveMods.js b/tests/baselines/reference/recursiveMods.js
index 86b3d47a48e..6f8304df658 100644
--- a/tests/baselines/reference/recursiveMods.js
+++ b/tests/baselines/reference/recursiveMods.js
@@ -35,7 +35,6 @@ var Foo;
     }());
     Foo.C = C;
 })(Foo = exports.Foo || (exports.Foo = {}));
-var Foo;
 (function (Foo) {
     function Bar() {
         if (true) {
diff --git a/tests/baselines/reference/reservedWords2.js b/tests/baselines/reference/reservedWords2.js
index a5f8a680bcc..a79a0564c78 100644
--- a/tests/baselines/reference/reservedWords2.js
+++ b/tests/baselines/reference/reservedWords2.js
@@ -34,7 +34,6 @@ debugger;
 if ()
     ;
 [1, 2];
-var ;
 (function () {
 })( || ( = {}));
 void {};
diff --git a/tests/baselines/reference/resolvingClassDeclarationWhenInBaseTypeResolution.js b/tests/baselines/reference/resolvingClassDeclarationWhenInBaseTypeResolution.js
index 6e621a18805..dafdb82ff5f 100644
--- a/tests/baselines/reference/resolvingClassDeclarationWhenInBaseTypeResolution.js
+++ b/tests/baselines/reference/resolvingClassDeclarationWhenInBaseTypeResolution.js
@@ -2302,7 +2302,6 @@ var quasiater;
     }());
     quasiater.bobrinskoi = bobrinskoi;
 })(quasiater || (quasiater = {}));
-var ruatanica;
 (function (ruatanica) {
     var americanus = (function (_super) {
         __extends(americanus, _super);
@@ -3225,7 +3224,6 @@ var panglima;
     }(argurus.dauricus));
     panglima.abidi = abidi;
 })(panglima || (panglima = {}));
-var quasiater;
 (function (quasiater) {
     var carolinensis = (function () {
         function carolinensis() {
@@ -3459,7 +3457,6 @@ var daubentonii;
     }());
     daubentonii.nesiotes = nesiotes;
 })(daubentonii || (daubentonii = {}));
-var nigra;
 (function (nigra) {
     var thalia = (function () {
         function thalia() {
@@ -3533,7 +3530,6 @@ var sagitta;
     }(minutus.portoricensis));
     sagitta.walkeri = walkeri;
 })(sagitta || (sagitta = {}));
-var minutus;
 (function (minutus) {
     var inez = (function (_super) {
         __extends(inez, _super);
@@ -3550,7 +3546,6 @@ var minutus;
     }(samarensis.pelurus));
     minutus.inez = inez;
 })(minutus || (minutus = {}));
-var macrorhinos;
 (function (macrorhinos) {
     var konganensis = (function (_super) {
         __extends(konganensis, _super);
@@ -3626,7 +3621,6 @@ var panamensis;
     }(ruatanica.hector));
     panamensis.linulus = linulus;
 })(panamensis || (panamensis = {}));
-var nigra;
 (function (nigra) {
     var gracilis = (function () {
         function gracilis() {
@@ -3960,7 +3954,6 @@ var samarensis;
     }());
     samarensis.cahirinus = cahirinus;
 })(samarensis || (samarensis = {}));
-var sagitta;
 (function (sagitta) {
     var leptoceros = (function (_super) {
         __extends(leptoceros, _super);
@@ -4001,7 +3994,6 @@ var sagitta;
     }(caurinus.johorensis));
     sagitta.leptoceros = leptoceros;
 })(sagitta || (sagitta = {}));
-var daubentonii;
 (function (daubentonii) {
     var nigricans = (function (_super) {
         __extends(nigricans, _super);
@@ -4027,7 +4019,6 @@ var dammermani;
     }());
     dammermani.siberu = siberu;
 })(dammermani || (dammermani = {}));
-var argurus;
 (function (argurus) {
     var pygmaea = (function (_super) {
         __extends(pygmaea, _super);
@@ -4109,7 +4100,6 @@ var chrysaeolus;
     }(caurinus.psilurus));
     chrysaeolus.sarasinorum = sarasinorum;
 })(chrysaeolus || (chrysaeolus = {}));
-var argurus;
 (function (argurus) {
     var wetmorei = (function () {
         function wetmorei() {
@@ -4160,7 +4150,6 @@ var argurus;
     }());
     argurus.wetmorei = wetmorei;
 })(argurus || (argurus = {}));
-var argurus;
 (function (argurus) {
     var oreas = (function (_super) {
         __extends(oreas, _super);
@@ -4219,7 +4208,6 @@ var argurus;
     }(lavali.wilsoni));
     argurus.oreas = oreas;
 })(argurus || (argurus = {}));
-var daubentonii;
 (function (daubentonii) {
     var arboreus = (function () {
         function arboreus() {
@@ -4410,7 +4398,6 @@ var provocax;
     }(lavali.wilsoni));
     provocax.melanoleuca = melanoleuca;
 })(provocax || (provocax = {}));
-var sagitta;
 (function (sagitta) {
     var sicarius = (function () {
         function sicarius() {
@@ -4431,7 +4418,6 @@ var sagitta;
     }());
     sagitta.sicarius = sicarius;
 })(sagitta || (sagitta = {}));
-var howi;
 (function (howi) {
     var marcanoi = (function (_super) {
         __extends(marcanoi, _super);
@@ -4526,7 +4512,6 @@ var howi;
     }(Lanthanum.megalonyx));
     howi.marcanoi = marcanoi;
 })(howi || (howi = {}));
-var argurus;
 (function (argurus) {
     var gilbertii = (function () {
         function gilbertii() {
@@ -4616,7 +4601,6 @@ var petrophilus;
     }());
     petrophilus.minutilla = minutilla;
 })(petrophilus || (petrophilus = {}));
-var lutreolus;
 (function (lutreolus) {
     var punicus = (function () {
         function punicus() {
@@ -4703,7 +4687,6 @@ var lutreolus;
     }());
     lutreolus.punicus = punicus;
 })(lutreolus || (lutreolus = {}));
-var macrorhinos;
 (function (macrorhinos) {
     var daphaenodon = (function () {
         function daphaenodon() {
@@ -4748,7 +4731,6 @@ var macrorhinos;
     }());
     macrorhinos.daphaenodon = daphaenodon;
 })(macrorhinos || (macrorhinos = {}));
-var sagitta;
 (function (sagitta) {
     var cinereus = (function () {
         function cinereus() {
@@ -4829,7 +4811,6 @@ var sagitta;
     }());
     sagitta.cinereus = cinereus;
 })(sagitta || (sagitta = {}));
-var nigra;
 (function (nigra) {
     var caucasica = (function () {
         function caucasica() {
@@ -5070,7 +5051,6 @@ var imperfecta;
     }(dogramacii.robustulus));
     imperfecta.ciliolabrum = ciliolabrum;
 })(imperfecta || (imperfecta = {}));
-var quasiater;
 (function (quasiater) {
     var wattsi = (function () {
         function wattsi() {
@@ -5103,7 +5083,6 @@ var quasiater;
     }());
     quasiater.wattsi = wattsi;
 })(quasiater || (quasiater = {}));
-var petrophilus;
 (function (petrophilus) {
     var sodyi = (function (_super) {
         __extends(sodyi, _super);
@@ -5168,7 +5147,6 @@ var petrophilus;
     }(quasiater.bobrinskoi));
     petrophilus.sodyi = sodyi;
 })(petrophilus || (petrophilus = {}));
-var caurinus;
 (function (caurinus) {
     var megaphyllus = (function (_super) {
         __extends(megaphyllus, _super);
@@ -5227,7 +5205,6 @@ var caurinus;
     }(imperfecta.lasiurus));
     caurinus.megaphyllus = megaphyllus;
 })(caurinus || (caurinus = {}));
-var minutus;
 (function (minutus) {
     var portoricensis = (function () {
         function portoricensis() {
@@ -5254,7 +5231,6 @@ var minutus;
     }());
     minutus.portoricensis = portoricensis;
 })(minutus || (minutus = {}));
-var lutreolus;
 (function (lutreolus) {
     var foina = (function () {
         function foina() {
@@ -5341,7 +5317,6 @@ var lutreolus;
     }());
     lutreolus.foina = foina;
 })(lutreolus || (lutreolus = {}));
-var lutreolus;
 (function (lutreolus) {
     var cor = (function (_super) {
         __extends(cor, _super);
@@ -5412,7 +5387,6 @@ var lutreolus;
     }(panglima.fundatus));
     lutreolus.cor = cor;
 })(lutreolus || (lutreolus = {}));
-var howi;
 (function (howi) {
     var coludo = (function () {
         function coludo() {
@@ -5433,7 +5407,6 @@ var howi;
     }());
     howi.coludo = coludo;
 })(howi || (howi = {}));
-var argurus;
 (function (argurus) {
     var germaini = (function (_super) {
         __extends(germaini, _super);
@@ -5456,7 +5429,6 @@ var argurus;
     }(gabriellae.amicus));
     argurus.germaini = germaini;
 })(argurus || (argurus = {}));
-var sagitta;
 (function (sagitta) {
     var stolzmanni = (function () {
         function stolzmanni() {
@@ -5531,7 +5503,6 @@ var sagitta;
     }());
     sagitta.stolzmanni = stolzmanni;
 })(sagitta || (sagitta = {}));
-var dammermani;
 (function (dammermani) {
     var melanops = (function (_super) {
         __extends(melanops, _super);
@@ -5620,7 +5591,6 @@ var dammermani;
     }(minutus.inez));
     dammermani.melanops = melanops;
 })(dammermani || (dammermani = {}));
-var argurus;
 (function (argurus) {
     var peninsulae = (function (_super) {
         __extends(peninsulae, _super);
@@ -5679,7 +5649,6 @@ var argurus;
     }(patas.uralensis));
     argurus.peninsulae = peninsulae;
 })(argurus || (argurus = {}));
-var argurus;
 (function (argurus) {
     var netscheri = (function () {
         function netscheri() {
@@ -5766,7 +5735,6 @@ var argurus;
     }());
     argurus.netscheri = netscheri;
 })(argurus || (argurus = {}));
-var ruatanica;
 (function (ruatanica) {
     var Praseodymium = (function (_super) {
         __extends(Praseodymium, _super);
@@ -5855,7 +5823,6 @@ var ruatanica;
     }(ruatanica.hector));
     ruatanica.Praseodymium = Praseodymium;
 })(ruatanica || (ruatanica = {}));
-var caurinus;
 (function (caurinus) {
     var johorensis = (function (_super) {
         __extends(johorensis, _super);
@@ -5872,7 +5839,6 @@ var caurinus;
     }(lutreolus.punicus));
     caurinus.johorensis = johorensis;
 })(caurinus || (caurinus = {}));
-var argurus;
 (function (argurus) {
     var luctuosa = (function () {
         function luctuosa() {
@@ -5887,7 +5853,6 @@ var argurus;
     }());
     argurus.luctuosa = luctuosa;
 })(argurus || (argurus = {}));
-var panamensis;
 (function (panamensis) {
     var setulosus = (function () {
         function setulosus() {
@@ -5944,7 +5909,6 @@ var panamensis;
     }());
     panamensis.setulosus = setulosus;
 })(panamensis || (panamensis = {}));
-var petrophilus;
 (function (petrophilus) {
     var rosalia = (function () {
         function rosalia() {
@@ -5983,7 +5947,6 @@ var petrophilus;
     }());
     petrophilus.rosalia = rosalia;
 })(petrophilus || (petrophilus = {}));
-var caurinus;
 (function (caurinus) {
     var psilurus = (function (_super) {
         __extends(psilurus, _super);
diff --git a/tests/baselines/reference/sourcemapValidationDuplicateNames.js b/tests/baselines/reference/sourcemapValidationDuplicateNames.js
index 360635fe74d..34804cc8227 100644
--- a/tests/baselines/reference/sourcemapValidationDuplicateNames.js
+++ b/tests/baselines/reference/sourcemapValidationDuplicateNames.js
@@ -19,7 +19,6 @@ var m1;
     }());
     m1.c = c;
 })(m1 || (m1 = {}));
-var m1;
 (function (m1) {
     var b = new m1.c();
 })(m1 || (m1 = {}));
diff --git a/tests/baselines/reference/sourcemapValidationDuplicateNames.js.map b/tests/baselines/reference/sourcemapValidationDuplicateNames.js.map
index 10225f979e5..2e1a02da8dd 100644
--- a/tests/baselines/reference/sourcemapValidationDuplicateNames.js.map
+++ b/tests/baselines/reference/sourcemapValidationDuplicateNames.js.map
@@ -1,2 +1,2 @@
 //// [sourcemapValidationDuplicateNames.js.map]
-{"version":3,"file":"sourcemapValidationDuplicateNames.js","sourceRoot":"","sources":["sourcemapValidationDuplicateNames.ts"],"names":[],"mappings":"AAAA,IAAO,EAAE,CAIR;AAJD,WAAO,EAAE;IACL,IAAI,CAAC,GAAG,EAAE,CAAC;IACX;QAAA;QACA,CAAC;QAAD,QAAC;IAAD,CAAC,AADD,IACC;IADY,IAAC,IACb,CAAA;AACL,CAAC,EAJM,EAAE,KAAF,EAAE,QAIR;AACD,IAAO,EAAE,CAER;AAFD,WAAO,EAAE;IACL,IAAI,CAAC,GAAG,IAAI,EAAE,CAAC,CAAC,EAAE,CAAC;AACvB,CAAC,EAFM,EAAE,KAAF,EAAE,QAER"}
\ No newline at end of file
+{"version":3,"file":"sourcemapValidationDuplicateNames.js","sourceRoot":"","sources":["sourcemapValidationDuplicateNames.ts"],"names":[],"mappings":"AAAA,IAAO,EAAE,CAIR;AAJD,WAAO,EAAE;IACL,IAAI,CAAC,GAAG,EAAE,CAAC;IACX;QAAA;QACA,CAAC;QAAD,QAAC;IAAD,CAAC,AADD,IACC;IADY,IAAC,IACb,CAAA;AACL,CAAC,EAJM,EAAE,KAAF,EAAE,QAIR;AACD,WAAO,EAAE;IACL,IAAI,CAAC,GAAG,IAAI,EAAE,CAAC,CAAC,EAAE,CAAC;AACvB,CAAC,EAFM,EAAE,KAAF,EAAE,QAER"}
\ No newline at end of file
diff --git a/tests/baselines/reference/sourcemapValidationDuplicateNames.sourcemap.txt b/tests/baselines/reference/sourcemapValidationDuplicateNames.sourcemap.txt
index 5ae487440ee..d4b98001a57 100644
--- a/tests/baselines/reference/sourcemapValidationDuplicateNames.sourcemap.txt
+++ b/tests/baselines/reference/sourcemapValidationDuplicateNames.sourcemap.txt
@@ -152,35 +152,18 @@ sourceFile:sourcemapValidationDuplicateNames.ts
 6 >Emitted(10, 13) Source(1, 10) + SourceIndex(0)
 7 >Emitted(10, 21) Source(5, 2) + SourceIndex(0)
 ---
->>>var m1;
-1 >
-2 >^^^^
-3 >    ^^
-4 >      ^
-5 >       ^^^^^^^^^^->
-1 >
-  >
-2 >module 
-3 >    m1
-4 >       {
-  >          var b = new m1.c();
-  >      }
-1 >Emitted(11, 1) Source(6, 1) + SourceIndex(0)
-2 >Emitted(11, 5) Source(6, 8) + SourceIndex(0)
-3 >Emitted(11, 7) Source(6, 10) + SourceIndex(0)
-4 >Emitted(11, 8) Source(8, 2) + SourceIndex(0)
----
 >>>(function (m1) {
-1->
+1 >
 2 >^^^^^^^^^^^
 3 >           ^^
 4 >             ^^^^^^^^^^^->
-1->
+1 >
+  >
 2 >module 
 3 >           m1
-1->Emitted(12, 1) Source(6, 1) + SourceIndex(0)
-2 >Emitted(12, 12) Source(6, 8) + SourceIndex(0)
-3 >Emitted(12, 14) Source(6, 10) + SourceIndex(0)
+1 >Emitted(11, 1) Source(6, 1) + SourceIndex(0)
+2 >Emitted(11, 12) Source(6, 8) + SourceIndex(0)
+3 >Emitted(11, 14) Source(6, 10) + SourceIndex(0)
 ---
 >>>    var b = new m1.c();
 1->^^^^
@@ -204,16 +187,16 @@ sourceFile:sourcemapValidationDuplicateNames.ts
 8 >                   c
 9 >                    ()
 10>                      ;
-1->Emitted(13, 5) Source(7, 5) + SourceIndex(0)
-2 >Emitted(13, 9) Source(7, 9) + SourceIndex(0)
-3 >Emitted(13, 10) Source(7, 10) + SourceIndex(0)
-4 >Emitted(13, 13) Source(7, 13) + SourceIndex(0)
-5 >Emitted(13, 17) Source(7, 17) + SourceIndex(0)
-6 >Emitted(13, 19) Source(7, 19) + SourceIndex(0)
-7 >Emitted(13, 20) Source(7, 20) + SourceIndex(0)
-8 >Emitted(13, 21) Source(7, 21) + SourceIndex(0)
-9 >Emitted(13, 23) Source(7, 23) + SourceIndex(0)
-10>Emitted(13, 24) Source(7, 24) + SourceIndex(0)
+1->Emitted(12, 5) Source(7, 5) + SourceIndex(0)
+2 >Emitted(12, 9) Source(7, 9) + SourceIndex(0)
+3 >Emitted(12, 10) Source(7, 10) + SourceIndex(0)
+4 >Emitted(12, 13) Source(7, 13) + SourceIndex(0)
+5 >Emitted(12, 17) Source(7, 17) + SourceIndex(0)
+6 >Emitted(12, 19) Source(7, 19) + SourceIndex(0)
+7 >Emitted(12, 20) Source(7, 20) + SourceIndex(0)
+8 >Emitted(12, 21) Source(7, 21) + SourceIndex(0)
+9 >Emitted(12, 23) Source(7, 23) + SourceIndex(0)
+10>Emitted(12, 24) Source(7, 24) + SourceIndex(0)
 ---
 >>>})(m1 || (m1 = {}));
 1 >
@@ -234,12 +217,12 @@ sourceFile:sourcemapValidationDuplicateNames.ts
 7 >             {
   >                var b = new m1.c();
   >            }
-1 >Emitted(14, 1) Source(8, 1) + SourceIndex(0)
-2 >Emitted(14, 2) Source(8, 2) + SourceIndex(0)
-3 >Emitted(14, 4) Source(6, 8) + SourceIndex(0)
-4 >Emitted(14, 6) Source(6, 10) + SourceIndex(0)
-5 >Emitted(14, 11) Source(6, 8) + SourceIndex(0)
-6 >Emitted(14, 13) Source(6, 10) + SourceIndex(0)
-7 >Emitted(14, 21) Source(8, 2) + SourceIndex(0)
+1 >Emitted(13, 1) Source(8, 1) + SourceIndex(0)
+2 >Emitted(13, 2) Source(8, 2) + SourceIndex(0)
+3 >Emitted(13, 4) Source(6, 8) + SourceIndex(0)
+4 >Emitted(13, 6) Source(6, 10) + SourceIndex(0)
+5 >Emitted(13, 11) Source(6, 8) + SourceIndex(0)
+6 >Emitted(13, 13) Source(6, 10) + SourceIndex(0)
+7 >Emitted(13, 21) Source(8, 2) + SourceIndex(0)
 ---
 >>>//# sourceMappingURL=sourcemapValidationDuplicateNames.js.map
\ No newline at end of file
diff --git a/tests/baselines/reference/staticMemberExportAccess.js b/tests/baselines/reference/staticMemberExportAccess.js
index 58fddf445ee..b0261e79c8e 100644
--- a/tests/baselines/reference/staticMemberExportAccess.js
+++ b/tests/baselines/reference/staticMemberExportAccess.js
@@ -30,7 +30,6 @@ var Sammy = (function () {
     };
     return Sammy;
 }());
-var Sammy;
 (function (Sammy) {
     Sammy.x = 1;
 })(Sammy || (Sammy = {}));
diff --git a/tests/baselines/reference/staticPropertyNotInClassType.js b/tests/baselines/reference/staticPropertyNotInClassType.js
index 60fd3b808ca..6caa108a710 100644
--- a/tests/baselines/reference/staticPropertyNotInClassType.js
+++ b/tests/baselines/reference/staticPropertyNotInClassType.js
@@ -56,7 +56,6 @@ var NonGeneric;
         });
         return C;
     }());
-    var C;
     (function (C) {
         C.bar = ''; // not reflected in class type
     })(C || (C = {}));
@@ -82,7 +81,6 @@ var Generic;
         });
         return C;
     }());
-    var C;
     (function (C) {
         C.bar = ''; // not reflected in class type
     })(C || (C = {}));
diff --git a/tests/baselines/reference/staticsNotInScopeInClodule.js b/tests/baselines/reference/staticsNotInScopeInClodule.js
index e10ed2b31d3..ccaace996cd 100644
--- a/tests/baselines/reference/staticsNotInScopeInClodule.js
+++ b/tests/baselines/reference/staticsNotInScopeInClodule.js
@@ -14,7 +14,6 @@ var Clod = (function () {
     return Clod;
 }());
 Clod.x = 10;
-var Clod;
 (function (Clod) {
     var p = x; // x isn't in scope here
 })(Clod || (Clod = {}));
diff --git a/tests/baselines/reference/subtypesOfAny.js b/tests/baselines/reference/subtypesOfAny.js
index 0b2965cb820..c07da732c1e 100644
--- a/tests/baselines/reference/subtypesOfAny.js
+++ b/tests/baselines/reference/subtypesOfAny.js
@@ -150,7 +150,6 @@ var E;
     E[E["A"] = 0] = "A";
 })(E || (E = {}));
 function f() { }
-var f;
 (function (f) {
     f.bar = 1;
 })(f || (f = {}));
@@ -159,7 +158,6 @@ var c = (function () {
     }
     return c;
 }());
-var c;
 (function (c) {
     c.bar = 1;
 })(c || (c = {}));
diff --git a/tests/baselines/reference/subtypesOfTypeParameter.js b/tests/baselines/reference/subtypesOfTypeParameter.js
index 10d9e3e42ec..f87fec1ddfc 100644
--- a/tests/baselines/reference/subtypesOfTypeParameter.js
+++ b/tests/baselines/reference/subtypesOfTypeParameter.js
@@ -143,7 +143,6 @@ var E;
     E[E["A"] = 0] = "A";
 })(E || (E = {}));
 function f() { }
-var f;
 (function (f) {
     f.bar = 1;
 })(f || (f = {}));
@@ -152,7 +151,6 @@ var c = (function () {
     }
     return c;
 }());
-var c;
 (function (c) {
     c.bar = 1;
 })(c || (c = {}));
diff --git a/tests/baselines/reference/subtypesOfTypeParameterWithConstraints2.js b/tests/baselines/reference/subtypesOfTypeParameterWithConstraints2.js
index 771c2ef74f5..a41ab1d4e2e 100644
--- a/tests/baselines/reference/subtypesOfTypeParameterWithConstraints2.js
+++ b/tests/baselines/reference/subtypesOfTypeParameterWithConstraints2.js
@@ -200,7 +200,6 @@ var E;
     E[E["A"] = 0] = "A";
 })(E || (E = {}));
 function f() { }
-var f;
 (function (f) {
     f.bar = 1;
 })(f || (f = {}));
@@ -209,7 +208,6 @@ var c = (function () {
     }
     return c;
 }());
-var c;
 (function (c) {
     c.bar = 1;
 })(c || (c = {}));
diff --git a/tests/baselines/reference/subtypesOfUnion.js b/tests/baselines/reference/subtypesOfUnion.js
index cc0fdea7346..8168798bce2 100644
--- a/tests/baselines/reference/subtypesOfUnion.js
+++ b/tests/baselines/reference/subtypesOfUnion.js
@@ -69,7 +69,6 @@ var A2 = (function () {
     return A2;
 }());
 function f() { }
-var f;
 (function (f) {
     f.bar = 1;
 })(f || (f = {}));
@@ -78,7 +77,6 @@ var c = (function () {
     }
     return c;
 }());
-var c;
 (function (c) {
     c.bar = 1;
 })(c || (c = {}));
diff --git a/tests/baselines/reference/systemModuleDeclarationMerging.js b/tests/baselines/reference/systemModuleDeclarationMerging.js
index d5994bc9f22..4dac69c2641 100644
--- a/tests/baselines/reference/systemModuleDeclarationMerging.js
+++ b/tests/baselines/reference/systemModuleDeclarationMerging.js
@@ -14,7 +14,7 @@ System.register([], function (exports_1, context_1) {
     "use strict";
     var __moduleName = context_1 && context_1.id;
     function F() { }
-    var F, C, C, E, E;
+    var C, E;
     exports_1("F", F);
     return {
         setters: [],
diff --git a/tests/baselines/reference/tsxEmit3.js b/tests/baselines/reference/tsxEmit3.js
index 33e1975cdbc..bf368f9b262 100644
--- a/tests/baselines/reference/tsxEmit3.js
+++ b/tests/baselines/reference/tsxEmit3.js
@@ -62,7 +62,6 @@ var M;
         // Foo, <Foo />;
     })(S = M.S || (M.S = {}));
 })(M || (M = {}));
-var M;
 (function (M) {
     // Emit M.Foo
     M.Foo, <M.Foo />;
@@ -74,12 +73,10 @@ var M;
         S.Bar, <S.Bar />;
     })(S = M.S || (M.S = {}));
 })(M || (M = {}));
-var M;
 (function (M) {
     // Emit M.S.Bar
     M.S.Bar, <M.S.Bar />;
 })(M || (M = {}));
-var M;
 (function (M_1) {
     var M = 100;
     // Emit M_1.Foo
diff --git a/tests/baselines/reference/tsxEmit3.js.map b/tests/baselines/reference/tsxEmit3.js.map
index 051be56f256..6e12addfb6b 100644
--- a/tests/baselines/reference/tsxEmit3.js.map
+++ b/tests/baselines/reference/tsxEmit3.js.map
@@ -1,2 +1,2 @@
 //// [file.jsx.map]
-{"version":3,"file":"file.jsx","sourceRoot":"","sources":["file.tsx"],"names":[],"mappings":"AAMA,IAAO,CAAC,CAQP;AARD,WAAO,CAAC;IACP;QAAmB;QAAgB,CAAC;QAAC,UAAC;IAAD,CAAC,AAAtC,IAAsC;IAAzB,KAAG,MAAsB,CAAA;IACtC,IAAc,CAAC,CAKd;IALD,WAAc,CAAC;QACd;YAAA;YAAmB,CAAC;YAAD,UAAC;QAAD,CAAC,AAApB,IAAoB;QAAP,KAAG,MAAI,CAAA;QAEpB,WAAW;QACX,gBAAgB;IACjB,CAAC,EALa,CAAC,GAAD,GAAC,KAAD,GAAC,QAKd;AACF,CAAC,EARM,CAAC,KAAD,CAAC,QAQP;AAED,IAAO,CAAC,CAYP;AAZD,WAAO,CAAC;IACP,aAAa;IACb,EAAA,GAAG,EAAE,CAAC,EAAA,GAAG,GAAG,CAAC;IAEb,IAAc,CAAC,CAMd;IAND,WAAc,CAAC;QACd,aAAa;QACb,EAAA,GAAG,EAAE,CAAC,EAAA,GAAG,GAAG,CAAC;QAEb,aAAa;QACb,EAAA,GAAG,EAAE,CAAC,EAAA,GAAG,GAAG,CAAC;IACd,CAAC,EANa,CAAC,GAAD,GAAC,KAAD,GAAC,QAMd;AAEF,CAAC,EAZM,CAAC,KAAD,CAAC,QAYP;AAED,IAAO,CAAC,CAGP;AAHD,WAAO,CAAC;IACP,eAAe;IACf,EAAA,CAAC,CAAC,GAAG,EAAE,CAAC,EAAA,CAAC,CAAC,GAAG,GAAG,CAAC;AAClB,CAAC,EAHM,CAAC,KAAD,CAAC,QAGP;AAED,IAAO,CAAC,CAIP;AAJD,WAAO,GAAC;IACP,IAAI,CAAC,GAAG,GAAG,CAAC;IACZ,eAAe;IACf,IAAA,GAAG,EAAE,CAAC,IAAA,GAAG,GAAG,CAAC;AACd,CAAC,EAJM,CAAC,KAAD,CAAC,QAIP"}
\ No newline at end of file
+{"version":3,"file":"file.jsx","sourceRoot":"","sources":["file.tsx"],"names":[],"mappings":"AAMA,IAAO,CAAC,CAQP;AARD,WAAO,CAAC;IACP;QAAmB;QAAgB,CAAC;QAAC,UAAC;IAAD,CAAC,AAAtC,IAAsC;IAAzB,KAAG,MAAsB,CAAA;IACtC,IAAc,CAAC,CAKd;IALD,WAAc,CAAC;QACd;YAAA;YAAmB,CAAC;YAAD,UAAC;QAAD,CAAC,AAApB,IAAoB;QAAP,KAAG,MAAI,CAAA;QAEpB,WAAW;QACX,gBAAgB;IACjB,CAAC,EALa,CAAC,GAAD,GAAC,KAAD,GAAC,QAKd;AACF,CAAC,EARM,CAAC,KAAD,CAAC,QAQP;AAED,WAAO,CAAC;IACP,aAAa;IACb,EAAA,GAAG,EAAE,CAAC,EAAA,GAAG,GAAG,CAAC;IAEb,IAAc,CAAC,CAMd;IAND,WAAc,CAAC;QACd,aAAa;QACb,EAAA,GAAG,EAAE,CAAC,EAAA,GAAG,GAAG,CAAC;QAEb,aAAa;QACb,EAAA,GAAG,EAAE,CAAC,EAAA,GAAG,GAAG,CAAC;IACd,CAAC,EANa,CAAC,GAAD,GAAC,KAAD,GAAC,QAMd;AAEF,CAAC,EAZM,CAAC,KAAD,CAAC,QAYP;AAED,WAAO,CAAC;IACP,eAAe;IACf,EAAA,CAAC,CAAC,GAAG,EAAE,CAAC,EAAA,CAAC,CAAC,GAAG,GAAG,CAAC;AAClB,CAAC,EAHM,CAAC,KAAD,CAAC,QAGP;AAED,WAAO,GAAC;IACP,IAAI,CAAC,GAAG,GAAG,CAAC;IACZ,eAAe;IACf,IAAA,GAAG,EAAE,CAAC,IAAA,GAAG,GAAG,CAAC;AACd,CAAC,EAJM,CAAC,KAAD,CAAC,QAIP"}
\ No newline at end of file
diff --git a/tests/baselines/reference/tsxEmit3.sourcemap.txt b/tests/baselines/reference/tsxEmit3.sourcemap.txt
index 02fec081e4c..d2ccdb264ba 100644
--- a/tests/baselines/reference/tsxEmit3.sourcemap.txt
+++ b/tests/baselines/reference/tsxEmit3.sourcemap.txt
@@ -288,46 +288,19 @@ sourceFile:file.tsx
 6 >Emitted(20, 11) Source(7, 9) + SourceIndex(0)
 7 >Emitted(20, 19) Source(15, 2) + SourceIndex(0)
 ---
->>>var M;
+>>>(function (M) {
 1 >
-2 >^^^^
-3 >    ^
-4 >     ^
-5 >      ^^^^^^^^^^->
+2 >^^^^^^^^^^^
+3 >           ^
+4 >            ^^^^^^->
 1 >
   >
   >
 2 >module 
-3 >    M
-4 >      {
-  >     	// Emit M.Foo
-  >     	Foo, <Foo />;
-  >     
-  >     	export module S {
-  >     		// Emit M.Foo
-  >     		Foo, <Foo />;
-  >     
-  >     		// Emit S.Bar
-  >     		Bar, <Bar />;
-  >     	}
-  >     
-  >     }
-1 >Emitted(21, 1) Source(17, 1) + SourceIndex(0)
-2 >Emitted(21, 5) Source(17, 8) + SourceIndex(0)
-3 >Emitted(21, 6) Source(17, 9) + SourceIndex(0)
-4 >Emitted(21, 7) Source(29, 2) + SourceIndex(0)
----
->>>(function (M) {
-1->
-2 >^^^^^^^^^^^
-3 >           ^
-4 >            ^^^^^^->
-1->
-2 >module 
 3 >           M
-1->Emitted(22, 1) Source(17, 1) + SourceIndex(0)
-2 >Emitted(22, 12) Source(17, 8) + SourceIndex(0)
-3 >Emitted(22, 13) Source(17, 9) + SourceIndex(0)
+1 >Emitted(21, 1) Source(17, 1) + SourceIndex(0)
+2 >Emitted(21, 12) Source(17, 8) + SourceIndex(0)
+3 >Emitted(21, 13) Source(17, 9) + SourceIndex(0)
 ---
 >>>    // Emit M.Foo
 1->^^^^
@@ -336,8 +309,8 @@ sourceFile:file.tsx
 1-> {
   >	
 2 >    // Emit M.Foo
-1->Emitted(23, 5) Source(18, 2) + SourceIndex(0)
-2 >Emitted(23, 18) Source(18, 15) + SourceIndex(0)
+1->Emitted(22, 5) Source(18, 2) + SourceIndex(0)
+2 >Emitted(22, 18) Source(18, 15) + SourceIndex(0)
 ---
 >>>    M.Foo, <M.Foo />;
 1->^^^^
@@ -359,15 +332,15 @@ sourceFile:file.tsx
 7 >              Foo
 8 >                  />
 9 >                    ;
-1->Emitted(24, 5) Source(19, 2) + SourceIndex(0)
-2 >Emitted(24, 7) Source(19, 2) + SourceIndex(0)
-3 >Emitted(24, 10) Source(19, 5) + SourceIndex(0)
-4 >Emitted(24, 12) Source(19, 7) + SourceIndex(0)
-5 >Emitted(24, 13) Source(19, 8) + SourceIndex(0)
-6 >Emitted(24, 15) Source(19, 8) + SourceIndex(0)
-7 >Emitted(24, 18) Source(19, 11) + SourceIndex(0)
-8 >Emitted(24, 21) Source(19, 14) + SourceIndex(0)
-9 >Emitted(24, 22) Source(19, 15) + SourceIndex(0)
+1->Emitted(23, 5) Source(19, 2) + SourceIndex(0)
+2 >Emitted(23, 7) Source(19, 2) + SourceIndex(0)
+3 >Emitted(23, 10) Source(19, 5) + SourceIndex(0)
+4 >Emitted(23, 12) Source(19, 7) + SourceIndex(0)
+5 >Emitted(23, 13) Source(19, 8) + SourceIndex(0)
+6 >Emitted(23, 15) Source(19, 8) + SourceIndex(0)
+7 >Emitted(23, 18) Source(19, 11) + SourceIndex(0)
+8 >Emitted(23, 21) Source(19, 14) + SourceIndex(0)
+9 >Emitted(23, 22) Source(19, 15) + SourceIndex(0)
 ---
 >>>    var S;
 1 >^^^^
@@ -387,10 +360,10 @@ sourceFile:file.tsx
   >         		// Emit S.Bar
   >         		Bar, <Bar />;
   >         	}
-1 >Emitted(25, 5) Source(21, 2) + SourceIndex(0)
-2 >Emitted(25, 9) Source(21, 16) + SourceIndex(0)
-3 >Emitted(25, 10) Source(21, 17) + SourceIndex(0)
-4 >Emitted(25, 11) Source(27, 3) + SourceIndex(0)
+1 >Emitted(24, 5) Source(21, 2) + SourceIndex(0)
+2 >Emitted(24, 9) Source(21, 16) + SourceIndex(0)
+3 >Emitted(24, 10) Source(21, 17) + SourceIndex(0)
+4 >Emitted(24, 11) Source(27, 3) + SourceIndex(0)
 ---
 >>>    (function (S) {
 1->^^^^
@@ -400,9 +373,9 @@ sourceFile:file.tsx
 1->
 2 >    export module 
 3 >               S
-1->Emitted(26, 5) Source(21, 2) + SourceIndex(0)
-2 >Emitted(26, 16) Source(21, 16) + SourceIndex(0)
-3 >Emitted(26, 17) Source(21, 17) + SourceIndex(0)
+1->Emitted(25, 5) Source(21, 2) + SourceIndex(0)
+2 >Emitted(25, 16) Source(21, 16) + SourceIndex(0)
+3 >Emitted(25, 17) Source(21, 17) + SourceIndex(0)
 ---
 >>>        // Emit M.Foo
 1->^^^^^^^^
@@ -411,8 +384,8 @@ sourceFile:file.tsx
 1-> {
   >		
 2 >        // Emit M.Foo
-1->Emitted(27, 9) Source(22, 3) + SourceIndex(0)
-2 >Emitted(27, 22) Source(22, 16) + SourceIndex(0)
+1->Emitted(26, 9) Source(22, 3) + SourceIndex(0)
+2 >Emitted(26, 22) Source(22, 16) + SourceIndex(0)
 ---
 >>>        M.Foo, <M.Foo />;
 1->^^^^^^^^
@@ -434,15 +407,15 @@ sourceFile:file.tsx
 7 >                  Foo
 8 >                      />
 9 >                        ;
-1->Emitted(28, 9) Source(23, 3) + SourceIndex(0)
-2 >Emitted(28, 11) Source(23, 3) + SourceIndex(0)
-3 >Emitted(28, 14) Source(23, 6) + SourceIndex(0)
-4 >Emitted(28, 16) Source(23, 8) + SourceIndex(0)
-5 >Emitted(28, 17) Source(23, 9) + SourceIndex(0)
-6 >Emitted(28, 19) Source(23, 9) + SourceIndex(0)
-7 >Emitted(28, 22) Source(23, 12) + SourceIndex(0)
-8 >Emitted(28, 25) Source(23, 15) + SourceIndex(0)
-9 >Emitted(28, 26) Source(23, 16) + SourceIndex(0)
+1->Emitted(27, 9) Source(23, 3) + SourceIndex(0)
+2 >Emitted(27, 11) Source(23, 3) + SourceIndex(0)
+3 >Emitted(27, 14) Source(23, 6) + SourceIndex(0)
+4 >Emitted(27, 16) Source(23, 8) + SourceIndex(0)
+5 >Emitted(27, 17) Source(23, 9) + SourceIndex(0)
+6 >Emitted(27, 19) Source(23, 9) + SourceIndex(0)
+7 >Emitted(27, 22) Source(23, 12) + SourceIndex(0)
+8 >Emitted(27, 25) Source(23, 15) + SourceIndex(0)
+9 >Emitted(27, 26) Source(23, 16) + SourceIndex(0)
 ---
 >>>        // Emit S.Bar
 1 >^^^^^^^^
@@ -452,8 +425,8 @@ sourceFile:file.tsx
   >
   >		
 2 >        // Emit S.Bar
-1 >Emitted(29, 9) Source(25, 3) + SourceIndex(0)
-2 >Emitted(29, 22) Source(25, 16) + SourceIndex(0)
+1 >Emitted(28, 9) Source(25, 3) + SourceIndex(0)
+2 >Emitted(28, 22) Source(25, 16) + SourceIndex(0)
 ---
 >>>        S.Bar, <S.Bar />;
 1->^^^^^^^^
@@ -476,15 +449,15 @@ sourceFile:file.tsx
 7 >                  Bar
 8 >                      />
 9 >                        ;
-1->Emitted(30, 9) Source(26, 3) + SourceIndex(0)
-2 >Emitted(30, 11) Source(26, 3) + SourceIndex(0)
-3 >Emitted(30, 14) Source(26, 6) + SourceIndex(0)
-4 >Emitted(30, 16) Source(26, 8) + SourceIndex(0)
-5 >Emitted(30, 17) Source(26, 9) + SourceIndex(0)
-6 >Emitted(30, 19) Source(26, 9) + SourceIndex(0)
-7 >Emitted(30, 22) Source(26, 12) + SourceIndex(0)
-8 >Emitted(30, 25) Source(26, 15) + SourceIndex(0)
-9 >Emitted(30, 26) Source(26, 16) + SourceIndex(0)
+1->Emitted(29, 9) Source(26, 3) + SourceIndex(0)
+2 >Emitted(29, 11) Source(26, 3) + SourceIndex(0)
+3 >Emitted(29, 14) Source(26, 6) + SourceIndex(0)
+4 >Emitted(29, 16) Source(26, 8) + SourceIndex(0)
+5 >Emitted(29, 17) Source(26, 9) + SourceIndex(0)
+6 >Emitted(29, 19) Source(26, 9) + SourceIndex(0)
+7 >Emitted(29, 22) Source(26, 12) + SourceIndex(0)
+8 >Emitted(29, 25) Source(26, 15) + SourceIndex(0)
+9 >Emitted(29, 26) Source(26, 16) + SourceIndex(0)
 ---
 >>>    })(S = M.S || (M.S = {}));
 1->^^^^
@@ -512,15 +485,15 @@ sourceFile:file.tsx
   >                      		// Emit S.Bar
   >                      		Bar, <Bar />;
   >                      	}
-1->Emitted(31, 5) Source(27, 2) + SourceIndex(0)
-2 >Emitted(31, 6) Source(27, 3) + SourceIndex(0)
-3 >Emitted(31, 8) Source(21, 16) + SourceIndex(0)
-4 >Emitted(31, 9) Source(21, 17) + SourceIndex(0)
-5 >Emitted(31, 12) Source(21, 16) + SourceIndex(0)
-6 >Emitted(31, 15) Source(21, 17) + SourceIndex(0)
-7 >Emitted(31, 20) Source(21, 16) + SourceIndex(0)
-8 >Emitted(31, 23) Source(21, 17) + SourceIndex(0)
-9 >Emitted(31, 31) Source(27, 3) + SourceIndex(0)
+1->Emitted(30, 5) Source(27, 2) + SourceIndex(0)
+2 >Emitted(30, 6) Source(27, 3) + SourceIndex(0)
+3 >Emitted(30, 8) Source(21, 16) + SourceIndex(0)
+4 >Emitted(30, 9) Source(21, 17) + SourceIndex(0)
+5 >Emitted(30, 12) Source(21, 16) + SourceIndex(0)
+6 >Emitted(30, 15) Source(21, 17) + SourceIndex(0)
+7 >Emitted(30, 20) Source(21, 16) + SourceIndex(0)
+8 >Emitted(30, 23) Source(21, 17) + SourceIndex(0)
+9 >Emitted(30, 31) Source(27, 3) + SourceIndex(0)
 ---
 >>>})(M || (M = {}));
 1 >
@@ -551,45 +524,27 @@ sourceFile:file.tsx
   >          	}
   >          
   >          }
-1 >Emitted(32, 1) Source(29, 1) + SourceIndex(0)
-2 >Emitted(32, 2) Source(29, 2) + SourceIndex(0)
-3 >Emitted(32, 4) Source(17, 8) + SourceIndex(0)
-4 >Emitted(32, 5) Source(17, 9) + SourceIndex(0)
-5 >Emitted(32, 10) Source(17, 8) + SourceIndex(0)
-6 >Emitted(32, 11) Source(17, 9) + SourceIndex(0)
-7 >Emitted(32, 19) Source(29, 2) + SourceIndex(0)
+1 >Emitted(31, 1) Source(29, 1) + SourceIndex(0)
+2 >Emitted(31, 2) Source(29, 2) + SourceIndex(0)
+3 >Emitted(31, 4) Source(17, 8) + SourceIndex(0)
+4 >Emitted(31, 5) Source(17, 9) + SourceIndex(0)
+5 >Emitted(31, 10) Source(17, 8) + SourceIndex(0)
+6 >Emitted(31, 11) Source(17, 9) + SourceIndex(0)
+7 >Emitted(31, 19) Source(29, 2) + SourceIndex(0)
 ---
->>>var M;
+>>>(function (M) {
 1 >
-2 >^^^^
-3 >    ^
-4 >     ^
-5 >      ^^^^^^^^^^->
+2 >^^^^^^^^^^^
+3 >           ^
+4 >            ^^^^^^^^->
 1 >
   >
   >
 2 >module 
-3 >    M
-4 >      {
-  >     	// Emit M.S.Bar
-  >     	S.Bar, <S.Bar />;
-  >     }
-1 >Emitted(33, 1) Source(31, 1) + SourceIndex(0)
-2 >Emitted(33, 5) Source(31, 8) + SourceIndex(0)
-3 >Emitted(33, 6) Source(31, 9) + SourceIndex(0)
-4 >Emitted(33, 7) Source(34, 2) + SourceIndex(0)
----
->>>(function (M) {
-1->
-2 >^^^^^^^^^^^
-3 >           ^
-4 >            ^^^^^^^^->
-1->
-2 >module 
 3 >           M
-1->Emitted(34, 1) Source(31, 1) + SourceIndex(0)
-2 >Emitted(34, 12) Source(31, 8) + SourceIndex(0)
-3 >Emitted(34, 13) Source(31, 9) + SourceIndex(0)
+1 >Emitted(32, 1) Source(31, 1) + SourceIndex(0)
+2 >Emitted(32, 12) Source(31, 8) + SourceIndex(0)
+3 >Emitted(32, 13) Source(31, 9) + SourceIndex(0)
 ---
 >>>    // Emit M.S.Bar
 1->^^^^
@@ -598,8 +553,8 @@ sourceFile:file.tsx
 1-> {
   >	
 2 >    // Emit M.S.Bar
-1->Emitted(35, 5) Source(32, 2) + SourceIndex(0)
-2 >Emitted(35, 20) Source(32, 17) + SourceIndex(0)
+1->Emitted(33, 5) Source(32, 2) + SourceIndex(0)
+2 >Emitted(33, 20) Source(32, 17) + SourceIndex(0)
 ---
 >>>    M.S.Bar, <M.S.Bar />;
 1->^^^^
@@ -629,19 +584,19 @@ sourceFile:file.tsx
 11>                  Bar
 12>                      />
 13>                        ;
-1->Emitted(36, 5) Source(33, 2) + SourceIndex(0)
-2 >Emitted(36, 7) Source(33, 2) + SourceIndex(0)
-3 >Emitted(36, 8) Source(33, 3) + SourceIndex(0)
-4 >Emitted(36, 9) Source(33, 4) + SourceIndex(0)
-5 >Emitted(36, 12) Source(33, 7) + SourceIndex(0)
-6 >Emitted(36, 14) Source(33, 9) + SourceIndex(0)
-7 >Emitted(36, 15) Source(33, 10) + SourceIndex(0)
-8 >Emitted(36, 17) Source(33, 10) + SourceIndex(0)
-9 >Emitted(36, 18) Source(33, 11) + SourceIndex(0)
-10>Emitted(36, 19) Source(33, 12) + SourceIndex(0)
-11>Emitted(36, 22) Source(33, 15) + SourceIndex(0)
-12>Emitted(36, 25) Source(33, 18) + SourceIndex(0)
-13>Emitted(36, 26) Source(33, 19) + SourceIndex(0)
+1->Emitted(34, 5) Source(33, 2) + SourceIndex(0)
+2 >Emitted(34, 7) Source(33, 2) + SourceIndex(0)
+3 >Emitted(34, 8) Source(33, 3) + SourceIndex(0)
+4 >Emitted(34, 9) Source(33, 4) + SourceIndex(0)
+5 >Emitted(34, 12) Source(33, 7) + SourceIndex(0)
+6 >Emitted(34, 14) Source(33, 9) + SourceIndex(0)
+7 >Emitted(34, 15) Source(33, 10) + SourceIndex(0)
+8 >Emitted(34, 17) Source(33, 10) + SourceIndex(0)
+9 >Emitted(34, 18) Source(33, 11) + SourceIndex(0)
+10>Emitted(34, 19) Source(33, 12) + SourceIndex(0)
+11>Emitted(34, 22) Source(33, 15) + SourceIndex(0)
+12>Emitted(34, 25) Source(33, 18) + SourceIndex(0)
+13>Emitted(34, 26) Source(33, 19) + SourceIndex(0)
 ---
 >>>})(M || (M = {}));
 1 >
@@ -662,46 +617,27 @@ sourceFile:file.tsx
   >          	// Emit M.S.Bar
   >          	S.Bar, <S.Bar />;
   >          }
-1 >Emitted(37, 1) Source(34, 1) + SourceIndex(0)
-2 >Emitted(37, 2) Source(34, 2) + SourceIndex(0)
-3 >Emitted(37, 4) Source(31, 8) + SourceIndex(0)
-4 >Emitted(37, 5) Source(31, 9) + SourceIndex(0)
-5 >Emitted(37, 10) Source(31, 8) + SourceIndex(0)
-6 >Emitted(37, 11) Source(31, 9) + SourceIndex(0)
-7 >Emitted(37, 19) Source(34, 2) + SourceIndex(0)
+1 >Emitted(35, 1) Source(34, 1) + SourceIndex(0)
+2 >Emitted(35, 2) Source(34, 2) + SourceIndex(0)
+3 >Emitted(35, 4) Source(31, 8) + SourceIndex(0)
+4 >Emitted(35, 5) Source(31, 9) + SourceIndex(0)
+5 >Emitted(35, 10) Source(31, 8) + SourceIndex(0)
+6 >Emitted(35, 11) Source(31, 9) + SourceIndex(0)
+7 >Emitted(35, 19) Source(34, 2) + SourceIndex(0)
 ---
->>>var M;
+>>>(function (M_1) {
 1 >
-2 >^^^^
-3 >    ^
-4 >     ^
-5 >      ^^^^^^^^^^^^->
+2 >^^^^^^^^^^^
+3 >           ^^^
+4 >              ^^^->
 1 >
   >
   >
 2 >module 
-3 >    M
-4 >      {
-  >     	var M = 100;
-  >     	// Emit M_1.Foo
-  >     	Foo, <Foo />;
-  >     }
-1 >Emitted(38, 1) Source(36, 1) + SourceIndex(0)
-2 >Emitted(38, 5) Source(36, 8) + SourceIndex(0)
-3 >Emitted(38, 6) Source(36, 9) + SourceIndex(0)
-4 >Emitted(38, 7) Source(40, 2) + SourceIndex(0)
----
->>>(function (M_1) {
-1->
-2 >^^^^^^^^^^^
-3 >           ^^^
-4 >              ^^^->
-1->
-2 >module 
 3 >           M
-1->Emitted(39, 1) Source(36, 1) + SourceIndex(0)
-2 >Emitted(39, 12) Source(36, 8) + SourceIndex(0)
-3 >Emitted(39, 15) Source(36, 9) + SourceIndex(0)
+1 >Emitted(36, 1) Source(36, 1) + SourceIndex(0)
+2 >Emitted(36, 12) Source(36, 8) + SourceIndex(0)
+3 >Emitted(36, 15) Source(36, 9) + SourceIndex(0)
 ---
 >>>    var M = 100;
 1->^^^^
@@ -718,12 +654,12 @@ sourceFile:file.tsx
 4 >          = 
 5 >            100
 6 >               ;
-1->Emitted(40, 5) Source(37, 2) + SourceIndex(0)
-2 >Emitted(40, 9) Source(37, 6) + SourceIndex(0)
-3 >Emitted(40, 10) Source(37, 7) + SourceIndex(0)
-4 >Emitted(40, 13) Source(37, 10) + SourceIndex(0)
-5 >Emitted(40, 16) Source(37, 13) + SourceIndex(0)
-6 >Emitted(40, 17) Source(37, 14) + SourceIndex(0)
+1->Emitted(37, 5) Source(37, 2) + SourceIndex(0)
+2 >Emitted(37, 9) Source(37, 6) + SourceIndex(0)
+3 >Emitted(37, 10) Source(37, 7) + SourceIndex(0)
+4 >Emitted(37, 13) Source(37, 10) + SourceIndex(0)
+5 >Emitted(37, 16) Source(37, 13) + SourceIndex(0)
+6 >Emitted(37, 17) Source(37, 14) + SourceIndex(0)
 ---
 >>>    // Emit M_1.Foo
 1->^^^^
@@ -732,8 +668,8 @@ sourceFile:file.tsx
 1->
   >	
 2 >    // Emit M_1.Foo
-1->Emitted(41, 5) Source(38, 2) + SourceIndex(0)
-2 >Emitted(41, 20) Source(38, 17) + SourceIndex(0)
+1->Emitted(38, 5) Source(38, 2) + SourceIndex(0)
+2 >Emitted(38, 20) Source(38, 17) + SourceIndex(0)
 ---
 >>>    M_1.Foo, <M_1.Foo />;
 1->^^^^
@@ -755,15 +691,15 @@ sourceFile:file.tsx
 7 >                  Foo
 8 >                      />
 9 >                        ;
-1->Emitted(42, 5) Source(39, 2) + SourceIndex(0)
-2 >Emitted(42, 9) Source(39, 2) + SourceIndex(0)
-3 >Emitted(42, 12) Source(39, 5) + SourceIndex(0)
-4 >Emitted(42, 14) Source(39, 7) + SourceIndex(0)
-5 >Emitted(42, 15) Source(39, 8) + SourceIndex(0)
-6 >Emitted(42, 19) Source(39, 8) + SourceIndex(0)
-7 >Emitted(42, 22) Source(39, 11) + SourceIndex(0)
-8 >Emitted(42, 25) Source(39, 14) + SourceIndex(0)
-9 >Emitted(42, 26) Source(39, 15) + SourceIndex(0)
+1->Emitted(39, 5) Source(39, 2) + SourceIndex(0)
+2 >Emitted(39, 9) Source(39, 2) + SourceIndex(0)
+3 >Emitted(39, 12) Source(39, 5) + SourceIndex(0)
+4 >Emitted(39, 14) Source(39, 7) + SourceIndex(0)
+5 >Emitted(39, 15) Source(39, 8) + SourceIndex(0)
+6 >Emitted(39, 19) Source(39, 8) + SourceIndex(0)
+7 >Emitted(39, 22) Source(39, 11) + SourceIndex(0)
+8 >Emitted(39, 25) Source(39, 14) + SourceIndex(0)
+9 >Emitted(39, 26) Source(39, 15) + SourceIndex(0)
 ---
 >>>})(M || (M = {}));
 1 >
@@ -786,12 +722,12 @@ sourceFile:file.tsx
   >          	// Emit M_1.Foo
   >          	Foo, <Foo />;
   >          }
-1 >Emitted(43, 1) Source(40, 1) + SourceIndex(0)
-2 >Emitted(43, 2) Source(40, 2) + SourceIndex(0)
-3 >Emitted(43, 4) Source(36, 8) + SourceIndex(0)
-4 >Emitted(43, 5) Source(36, 9) + SourceIndex(0)
-5 >Emitted(43, 10) Source(36, 8) + SourceIndex(0)
-6 >Emitted(43, 11) Source(36, 9) + SourceIndex(0)
-7 >Emitted(43, 19) Source(40, 2) + SourceIndex(0)
+1 >Emitted(40, 1) Source(40, 1) + SourceIndex(0)
+2 >Emitted(40, 2) Source(40, 2) + SourceIndex(0)
+3 >Emitted(40, 4) Source(36, 8) + SourceIndex(0)
+4 >Emitted(40, 5) Source(36, 9) + SourceIndex(0)
+5 >Emitted(40, 10) Source(36, 8) + SourceIndex(0)
+6 >Emitted(40, 11) Source(36, 9) + SourceIndex(0)
+7 >Emitted(40, 19) Source(40, 2) + SourceIndex(0)
 ---
 >>>//# sourceMappingURL=file.jsx.map
\ No newline at end of file
diff --git a/tests/baselines/reference/tsxPreserveEmit1.js b/tests/baselines/reference/tsxPreserveEmit1.js
index b9a7d369fc0..feb314ee2e6 100644
--- a/tests/baselines/reference/tsxPreserveEmit1.js
+++ b/tests/baselines/reference/tsxPreserveEmit1.js
@@ -41,7 +41,6 @@ define(["require", "exports", "react", "react-router"], function (require, expor
     var M;
     (function (M) {
     })(M || (M = {}));
-    var M;
     (function (M) {
         // Should emit 'M.X' in both opening and closing tags
         var y = <M.X></M.X>;
diff --git a/tests/baselines/reference/tsxReactEmit6.js b/tests/baselines/reference/tsxReactEmit6.js
index a85c6baa687..85aa8c123c9 100644
--- a/tests/baselines/reference/tsxReactEmit6.js
+++ b/tests/baselines/reference/tsxReactEmit6.js
@@ -39,7 +39,6 @@ var __assign = (this && this.__assign) || Object.assign || function(t) {
 var M;
 (function (M) {
 })(M || (M = {}));
-var M;
 (function (M) {
     // Should emit M.React.createElement
     //  and M.React.__spread
diff --git a/tests/baselines/reference/typeOfEnumAndVarRedeclarations.js b/tests/baselines/reference/typeOfEnumAndVarRedeclarations.js
index 391c9c1679a..b803071d27f 100644
--- a/tests/baselines/reference/typeOfEnumAndVarRedeclarations.js
+++ b/tests/baselines/reference/typeOfEnumAndVarRedeclarations.js
@@ -15,7 +15,6 @@ var E;
 (function (E) {
     E[E["a"] = 0] = "a";
 })(E || (E = {}));
-var E;
 (function (E) {
     E[E["b"] = 1] = "b";
 })(E || (E = {}));
diff --git a/tests/baselines/reference/typeofANonExportedType.js b/tests/baselines/reference/typeofANonExportedType.js
index 76e908e622d..5c99948e9c9 100644
--- a/tests/baselines/reference/typeofANonExportedType.js
+++ b/tests/baselines/reference/typeofANonExportedType.js
@@ -77,7 +77,6 @@ var E;
     E[E["A"] = 0] = "A";
 })(E || (E = {}));
 function foo() { }
-var foo;
 (function (foo) {
     foo.y = 1;
     var C = (function () {
diff --git a/tests/baselines/reference/typeofAnExportedType.js b/tests/baselines/reference/typeofAnExportedType.js
index 0930039d253..91b19d9bebd 100644
--- a/tests/baselines/reference/typeofAnExportedType.js
+++ b/tests/baselines/reference/typeofAnExportedType.js
@@ -80,7 +80,6 @@ exports.Z = M;
 var E = exports.E;
 function foo() { }
 exports.foo = foo;
-var foo;
 (function (foo) {
     foo.y = 1;
     var C = (function () {
diff --git a/tests/baselines/reference/undefinedIsSubtypeOfEverything.js b/tests/baselines/reference/undefinedIsSubtypeOfEverything.js
index 513464daa85..2f78fd11797 100644
--- a/tests/baselines/reference/undefinedIsSubtypeOfEverything.js
+++ b/tests/baselines/reference/undefinedIsSubtypeOfEverything.js
@@ -250,7 +250,6 @@ var D11 = (function (_super) {
     return D11;
 }(Base));
 function f() { }
-var f;
 (function (f) {
     f.bar = 1;
 })(f || (f = {}));
@@ -266,7 +265,6 @@ var c = (function () {
     }
     return c;
 }());
-var c;
 (function (c) {
     c.bar = 1;
 })(c || (c = {}));
diff --git a/tests/baselines/reference/undefinedTypeAssignment4.js b/tests/baselines/reference/undefinedTypeAssignment4.js
index a5d7a117a9d..575042b72c0 100644
--- a/tests/baselines/reference/undefinedTypeAssignment4.js
+++ b/tests/baselines/reference/undefinedTypeAssignment4.js
@@ -18,7 +18,6 @@ var undefined = (function () {
     }
     return undefined;
 }());
-var undefined;
 (function (undefined) {
     undefined.x = 42;
 })(undefined || (undefined = {}));
diff --git a/tests/baselines/reference/unexportedInstanceClassVariables.js b/tests/baselines/reference/unexportedInstanceClassVariables.js
index 7ac4f6d1b16..5cb0723931a 100644
--- a/tests/baselines/reference/unexportedInstanceClassVariables.js
+++ b/tests/baselines/reference/unexportedInstanceClassVariables.js
@@ -21,7 +21,6 @@ var M;
         return A;
     }());
 })(M || (M = {}));
-var M;
 (function (M) {
     var A = (function () {
         function A() {
diff --git a/tests/baselines/reference/unionSubtypeIfEveryConstituentTypeIsSubtype.js b/tests/baselines/reference/unionSubtypeIfEveryConstituentTypeIsSubtype.js
index c1c6918c770..a8cc0e12d27 100644
--- a/tests/baselines/reference/unionSubtypeIfEveryConstituentTypeIsSubtype.js
+++ b/tests/baselines/reference/unionSubtypeIfEveryConstituentTypeIsSubtype.js
@@ -164,7 +164,6 @@ var E2;
     E2[E2["A"] = 0] = "A";
 })(E2 || (E2 = {}));
 function f() { }
-var f;
 (function (f) {
     f.bar = 1;
 })(f || (f = {}));
@@ -173,7 +172,6 @@ var c = (function () {
     }
     return c;
 }());
-var c;
 (function (c) {
     c.bar = 1;
 })(c || (c = {}));
diff --git a/tests/baselines/reference/varNameConflictsWithImportInDifferentPartOfModule.js b/tests/baselines/reference/varNameConflictsWithImportInDifferentPartOfModule.js
index 870b01eda8e..db5bad4009a 100644
--- a/tests/baselines/reference/varNameConflictsWithImportInDifferentPartOfModule.js
+++ b/tests/baselines/reference/varNameConflictsWithImportInDifferentPartOfModule.js
@@ -13,7 +13,6 @@ var M1;
     M1.q = 5;
     M1.s = '';
 })(M1 || (M1 = {}));
-var M1;
 (function (M1) {
     M1.q = M1.s; // Should be an error but isn't
 })(M1 || (M1 = {}));
diff --git a/tests/cases/compiler/es6modulekindWithES5Target12.ts b/tests/cases/compiler/es6modulekindWithES5Target12.ts
new file mode 100644
index 00000000000..3bca121a57d
--- /dev/null
+++ b/tests/cases/compiler/es6modulekindWithES5Target12.ts
@@ -0,0 +1,39 @@
+// @target: es5
+// @module: es2015
+
+export class C {
+}
+
+export namespace C {
+    export const x = 1;
+}
+
+export enum E {
+    w = 1
+}
+
+export enum E {
+    x = 2
+}
+
+export namespace E {
+    export const y = 1;
+}
+
+export namespace E {
+    export const z = 1;
+}
+
+export namespace N {
+}
+
+export namespace N {
+    export const x = 1;
+}
+
+export function F() {
+}
+
+export namespace F {
+    export const x = 1;
+}
\ No newline at end of file