Merge branch 'master' into abstract-classes2

Jakefile.js

@@ -105,6 +105,14 @@ var serverSources = [
     return path.join(serverDirectory, f);
 });
 
+var languageServiceLibrarySources = [
+    "editorServices.ts",
+    "protocol.d.ts",
+    "session.ts"
+].map(function (f) {
+    return path.join(serverDirectory, f);
+}).concat(servicesSources);
+
 var harnessSources = [
     "harness.ts",
     "sourceMapRecorder.ts",
@@ -361,7 +369,7 @@ compileFile(servicesFile, servicesSources,[builtLocalDirectory, copyright].conca
                 // Create the node definition file by replacing 'ts' module with '"typescript"' as a module.
                 jake.cpR(standaloneDefinitionsFile, nodeDefinitionsFile, {silent: true});
                 var definitionFileContents = fs.readFileSync(nodeDefinitionsFile).toString();
-                definitionFileContents = definitionFileContents.replace(/declare module ts/g, 'declare module "typescript"');
+                definitionFileContents = definitionFileContents.replace(/declare (namespace|module) ts/g, 'declare module "typescript"');
                 fs.writeFileSync(nodeDefinitionsFile, definitionFileContents);
             });
 
@@ -369,6 +377,20 @@ compileFile(servicesFile, servicesSources,[builtLocalDirectory, copyright].conca
 var serverFile = path.join(builtLocalDirectory, "tsserver.js");
 compileFile(serverFile, serverSources,[builtLocalDirectory, copyright].concat(serverSources), /*prefixes*/ [copyright], /*useBuiltCompiler*/ true);
 
+var lsslFile = path.join(builtLocalDirectory, "tslssl.js");
+compileFile(
+    lsslFile, 
+    languageServiceLibrarySources, 
+    [builtLocalDirectory, copyright].concat(languageServiceLibrarySources),
+    /*prefixes*/ [copyright], 
+    /*useBuiltCompiler*/ true, 
+    /*noOutFile*/ false, 
+    /*generateDeclarations*/ true);
+
+// Local target to build the language service server library
+desc("Builds language service server library");
+task("lssl", [lsslFile]);
+
 // Local target to build the compiler and services
 desc("Builds the full compiler and services");
 task("local", ["generate-diagnostics", "lib", tscFile, servicesFile, nodeDefinitionsFile, serverFile]);

bin/tsc.js

@@ -24740,7 +24740,7 @@ var ts;
                         emitDeclarationName(node);
                         write("\", ");
                         emitDeclarationName(node);
-                        write(")");
+                        write(");");
                     }
                     emitExportMemberAssignments(node.name);
                 }
@@ -24848,7 +24848,7 @@ var ts;
                         emitDeclarationName(node);
                         write("\", ");
                         emitDeclarationName(node);
-                        write(")");
+                        write(");");
                     }
                     emitExportMemberAssignments(node.name);
                 }

bin/tsserver.js

@@ -25131,7 +25131,7 @@ var ts;
                         emitDeclarationName(node);
                         write("\", ");
                         emitDeclarationName(node);
-                        write(")");
+                        write(");");
                     }
                     emitExportMemberAssignments(node.name);
                 }
@@ -25239,7 +25239,7 @@ var ts;
                         emitDeclarationName(node);
                         write("\", ");
                         emitDeclarationName(node);
-                        write(")");
+                        write(");");
                     }
                     emitExportMemberAssignments(node.name);
                 }

bin/typescript.js

@@ -29466,7 +29466,7 @@ var ts;
                         emitDeclarationName(node);
                         write("\", ");
                         emitDeclarationName(node);
-                        write(")");
+                        write(");");
                     }
                     emitExportMemberAssignments(node.name);
                 }
@@ -29576,7 +29576,7 @@ var ts;
                         emitDeclarationName(node);
                         write("\", ");
                         emitDeclarationName(node);
-                        write(")");
+                        write(");");
                     }
                     emitExportMemberAssignments(node.name);
                 }

bin/typescriptServices.js

@@ -29466,7 +29466,7 @@ var ts;
                         emitDeclarationName(node);
                         write("\", ");
                         emitDeclarationName(node);
-                        write(")");
+                        write(");");
                     }
                     emitExportMemberAssignments(node.name);
                 }
@@ -29576,7 +29576,7 @@ var ts;
                         emitDeclarationName(node);
                         write("\", ");
                         emitDeclarationName(node);
-                        write(")");
+                        write(");");
                     }
                     emitExportMemberAssignments(node.name);
                 }

src/compiler/checker.ts

@@ -159,6 +159,14 @@ namespace ts {
             }
         };
 
+        let subtypeRelation: Map<RelationComparisonResult> = {};
+        let assignableRelation: Map<RelationComparisonResult> = {};
+        let identityRelation: Map<RelationComparisonResult> = {};
+
+        initializeTypeChecker();
+
+        return checker;
+
         function getEmitResolver(sourceFile?: SourceFile) {
             // Ensure we have all the type information in place for this file so that all the
             // emitter questions of this resolver will return the right information.
@@ -357,21 +365,38 @@ namespace ts {
                     case SyntaxKind.SourceFile:
                         if (!isExternalModule(<SourceFile>location)) break;
                     case SyntaxKind.ModuleDeclaration:
-                        if (result = getSymbol(getSymbolOfNode(location).exports, name, meaning & SymbolFlags.ModuleMember)) {
-                            if (result.flags & meaning || !(result.flags & SymbolFlags.Alias && getDeclarationOfAliasSymbol(result).kind === SyntaxKind.ExportSpecifier)) {
-                                break loop;
-                            }
-                            result = undefined;
-                        }
-                        else if (location.kind === SyntaxKind.SourceFile ||
+                        let moduleExports = getSymbolOfNode(location).exports;
+                        if (location.kind === SyntaxKind.SourceFile ||
                             (location.kind === SyntaxKind.ModuleDeclaration && (<ModuleDeclaration>location).name.kind === SyntaxKind.StringLiteral)) {
-                            result = getSymbolOfNode(location).exports["default"];
+                            
+                            // It's an external module. Because of module/namespace merging, a module's exports are in scope,
+                            // yet we never want to treat an export specifier as putting a member in scope. Therefore,
+                            // if the name we find is purely an export specifier, it is not actually considered in scope.
+                            // Two things to note about this:
+                            //     1. We have to check this without calling getSymbol. The problem with calling getSymbol
+                            //        on an export specifier is that it might find the export specifier itself, and try to
+                            //        resolve it as an alias. This will cause the checker to consider the export specifier
+                            //        a circular alias reference when it might not be.
+                            //     2. We check === SymbolFlags.Alias in order to check that the symbol is *purely*
+                            //        an alias. If we used &, we'd be throwing out symbols that have non alias aspects,
+                            //        which is not the desired behavior.
+                            if (hasProperty(moduleExports, name) &&
+                                moduleExports[name].flags === SymbolFlags.Alias &&
+                                getDeclarationOfKind(moduleExports[name], SyntaxKind.ExportSpecifier)) {
+                                break;
+                            }
+
+                            result = moduleExports["default"];
                             let localSymbol = getLocalSymbolForExportDefault(result);
                             if (result && localSymbol && (result.flags & meaning) && localSymbol.name === name) {
                                 break loop;
                             }
                             result = undefined;
                         }
+
+                        if (result = getSymbol(moduleExports, name, meaning & SymbolFlags.ModuleMember)) {
+                            break loop;
+                        }
                         break;
                     case SyntaxKind.EnumDeclaration:
                         if (result = getSymbol(getSymbolOfNode(location).exports, name, meaning & SymbolFlags.EnumMember)) {
@@ -2639,7 +2664,8 @@ namespace ts {
                 }
                 let baseConstructorType = checkExpression(baseTypeNode.expression);
                 if (baseConstructorType.flags & TypeFlags.ObjectType) {
-                    // Force resolution of members such that we catch circularities
+                    // Resolving the members of a class requires us to resolve the base class of that class.
+                    // We force resolution here such that we catch circularities now.
                     resolveObjectOrUnionTypeMembers(baseConstructorType);
                 }
                 if (!popTypeResolution()) {
@@ -2647,7 +2673,7 @@ namespace ts {
                     return type.resolvedBaseConstructorType = unknownType;
                 }
                 if (baseConstructorType !== unknownType && baseConstructorType !== nullType && !isConstructorType(baseConstructorType)) {
-                    error(baseTypeNode.expression, Diagnostics.Base_expression_is_not_of_a_constructor_function_type);
+                    error(baseTypeNode.expression, Diagnostics.Type_0_is_not_a_constructor_function_type, typeToString(baseConstructorType));
                     return type.resolvedBaseConstructorType = unknownType;
                 }
                 type.resolvedBaseConstructorType = baseConstructorType;
@@ -2699,7 +2725,7 @@ namespace ts {
                 return;
             }
             if (!(getTargetType(baseType).flags & (TypeFlags.Class | TypeFlags.Interface))) {
-                error(baseTypeNode.expression, Diagnostics.Base_constructor_does_not_return_a_class_or_interface_type);
+                error(baseTypeNode.expression, Diagnostics.Base_constructor_return_type_0_is_not_a_class_or_interface_type, typeToString(baseType));
                 return;
             }
             if (type === baseType || hasBaseType(<InterfaceType>baseType, type)) {
@@ -3599,7 +3625,7 @@ namespace ts {
                             // -> typeParameter and symbol.declaration originate from the same type parameter list
                             // -> illegal for all declarations in symbol
                             // forEach === exists
-                            links.isIllegalTypeReferenceInConstraint = forEach(symbol.declarations, d => d.parent == typeParameter.parent);
+                            links.isIllegalTypeReferenceInConstraint = forEach(symbol.declarations, d => d.parent === typeParameter.parent);
                         }
                     }
                     if (links.isIllegalTypeReferenceInConstraint) {
@@ -4220,10 +4246,6 @@ namespace ts {
 
         // TYPE CHECKING
 
-        let subtypeRelation: Map<RelationComparisonResult> = {};
-        let assignableRelation: Map<RelationComparisonResult> = {};
-        let identityRelation: Map<RelationComparisonResult> = {};
-
         function isTypeIdenticalTo(source: Type, target: Type): boolean {
             return checkTypeRelatedTo(source, target, identityRelation, /*errorNode*/ undefined);
         }
@@ -5777,6 +5799,7 @@ namespace ts {
                 let signature = getResolvedSignature(expr);
 
                 if (signature.typePredicate &&
+                    expr.arguments[signature.typePredicate.parameterIndex] &&
                     getSymbolAtLocation(expr.arguments[signature.typePredicate.parameterIndex]) === symbol) {
 
                     if (!assumeTrue) {
@@ -5979,7 +6002,9 @@ namespace ts {
             let baseClassType = classType && getBaseTypes(classType)[0];
 
             if (!baseClassType) {
-                error(node, Diagnostics.super_can_only_be_referenced_in_a_derived_class);
+                if (!classDeclaration || !getClassExtendsHeritageClauseElement(classDeclaration)) {
+                    error(node, Diagnostics.super_can_only_be_referenced_in_a_derived_class);
+                }
                 return unknownType;
             }
 
@@ -8548,7 +8573,7 @@ namespace ts {
         // contextually typed function and arrow expressions in the initial phase.
         function checkExpression(node: Expression | QualifiedName, contextualMapper?: TypeMapper): Type {
             let type: Type;
-            if (node.kind == SyntaxKind.QualifiedName) {
+            if (node.kind === SyntaxKind.QualifiedName) {
                 type = checkQualifiedName(<QualifiedName>node);
             }
             else {
@@ -9032,15 +9057,16 @@ namespace ts {
             checkDecorators(node);
         }
 
-        function checkTypeArgumentsAndConstraints(typeParameters: TypeParameter[], typeArguments: TypeNode[]) {
-            for (let i = 0; i < typeArguments.length; i++) {
-                let typeArgument = typeArguments[i];
-                checkSourceElement(typeArgument);
+        function checkTypeArgumentConstraints(typeParameters: TypeParameter[], typeArguments: TypeNode[]): boolean {
+            let result = true;
+            for (let i = 0; i < typeParameters.length; i++) {
                 let constraint = getConstraintOfTypeParameter(typeParameters[i]);
-                if (produceDiagnostics && constraint) {
-                    checkTypeAssignableTo(getTypeFromTypeNode(typeArgument), constraint, typeArgument, Diagnostics.Type_0_does_not_satisfy_the_constraint_1);
+                if (constraint) {
+                    let typeArgument = typeArguments[i];
+                    result = result && checkTypeAssignableTo(getTypeFromTypeNode(typeArgument), constraint, typeArgument, Diagnostics.Type_0_does_not_satisfy_the_constraint_1);
                 }
             }
+            return result;
         }
 
         function checkTypeReferenceNode(node: TypeReferenceNode | ExpressionWithTypeArguments) {
@@ -9048,9 +9074,12 @@ namespace ts {
             let type = getTypeFromTypeReference(node);
             if (type !== unknownType && node.typeArguments) {
                 // Do type argument local checks only if referenced type is successfully resolved
-                let symbol = getNodeLinks(node).resolvedSymbol;
-                let typeParameters = symbol.flags & SymbolFlags.TypeAlias ? getSymbolLinks(symbol).typeParameters : (<TypeReference>type).target.localTypeParameters;
-                checkTypeArgumentsAndConstraints(typeParameters, node.typeArguments);
+                forEach(node.typeArguments, checkSourceElement);
+                if (produceDiagnostics) {
+                    let symbol = getNodeLinks(node).resolvedSymbol;
+                    let typeParameters = symbol.flags & SymbolFlags.TypeAlias ? getSymbolLinks(symbol).typeParameters : (<TypeReference>type).target.localTypeParameters;
+                    checkTypeArgumentConstraints(typeParameters, node.typeArguments);
+                }
             }
         }
 
@@ -9995,7 +10024,7 @@ namespace ts {
         function checkForStatement(node: ForStatement) {
             // Grammar checking
             if (!checkGrammarStatementInAmbientContext(node)) {
-                if (node.initializer && node.initializer.kind == SyntaxKind.VariableDeclarationList) {
+                if (node.initializer && node.initializer.kind === SyntaxKind.VariableDeclarationList) {
                     checkGrammarVariableDeclarationList(<VariableDeclarationList>node.initializer);
                 }
             }
@@ -10665,8 +10694,12 @@ namespace ts {
                     let baseType = baseTypes[0];
                     let staticBaseType = getBaseConstructorTypeOfClass(type);
                     if (baseTypeNode.typeArguments) {
-                        let constructors = getConstructorsForTypeArguments(staticBaseType, baseTypeNode.typeArguments);
-                        checkTypeArgumentsAndConstraints(constructors[0].typeParameters, baseTypeNode.typeArguments);
+                        forEach(baseTypeNode.typeArguments, checkSourceElement);
+                        for (let constructor of getConstructorsForTypeArguments(staticBaseType, baseTypeNode.typeArguments)) {
+                            if (!checkTypeArgumentConstraints(constructor.typeParameters, baseTypeNode.typeArguments)) {
+                                break;
+                            }
+                        }
                     }
                     checkTypeAssignableTo(type, baseType, node.name || node, Diagnostics.Class_0_incorrectly_extends_base_class_1);
                     checkTypeAssignableTo(staticType, getTypeWithoutSignatures(staticBaseType), node.name || node,
@@ -10676,7 +10709,9 @@ namespace ts {
 
                     if (!(staticBaseType.symbol && staticBaseType.symbol.flags & SymbolFlags.Class)) {
                         // When the static base type is a "class-like" constructor function (but not actually a class), we verify
-                        // that all instantiated base constructor signatures return the same type.
+                        // that all instantiated base constructor signatures return the same type. We can simply compare the type
+                        // references (as opposed to checking the structure of the types) because elsewhere we have already checked
+                        // that the base type is a class or interface type (and not, for example, an anonymous object type).
                         let constructors = getInstantiatedConstructorsForTypeArguments(staticBaseType, baseTypeNode.typeArguments);
                         if (forEach(constructors, sig => getReturnTypeOfSignature(sig) !== baseType)) {
                             error(baseTypeNode.expression, Diagnostics.Base_constructors_must_all_have_the_same_return_type);
@@ -11888,7 +11923,7 @@ namespace ts {
         }
 
         function isTypeDeclarationName(name: Node): boolean {
-            return name.kind == SyntaxKind.Identifier &&
+            return name.kind === SyntaxKind.Identifier &&
                 isTypeDeclaration(name.parent) &&
                 (<Declaration>name.parent).name === name;
         }
@@ -12057,7 +12092,7 @@ namespace ts {
 
                 case SyntaxKind.NumericLiteral:
                     // index access
-                    if (node.parent.kind == SyntaxKind.ElementAccessExpression && (<ElementAccessExpression>node.parent).argumentExpression === node) {
+                    if (node.parent.kind === SyntaxKind.ElementAccessExpression && (<ElementAccessExpression>node.parent).argumentExpression === node) {
                         let objectType = checkExpression((<ElementAccessExpression>node.parent).expression);
                         if (objectType === unknownType) return undefined;
                         let apparentType = getApparentType(objectType);
@@ -12093,7 +12128,7 @@ namespace ts {
                 return getTypeOfExpression(<Expression>node);
             }
 
-            if (isClassExtendsExpressionWithTypeArguments(node)) {
+            if (isExpressionWithTypeArgumentsInClassExtendsClause(node)) {
                 // A SyntaxKind.ExpressionWithTypeArguments is considered a type node, except when it occurs in the
                 // extends clause of a class. We handle that case here.
                 return getBaseTypes(<InterfaceType>getDeclaredTypeOfSymbol(getSymbolOfNode(node.parent.parent)))[0];
@@ -13730,9 +13765,5 @@ namespace ts {
                 return true;
             }
         }
-
-        initializeTypeChecker();
-
-        return checker;
     }
 }

src/compiler/core.ts

@@ -572,7 +572,7 @@ namespace ts {
     export function getNormalizedPathComponents(path: string, currentDirectory: string) {
         path = normalizeSlashes(path);
         let rootLength = getRootLength(path);
-        if (rootLength == 0) {
+        if (rootLength === 0) {
             // If the path is not rooted it is relative to current directory
             path = combinePaths(normalizeSlashes(currentDirectory), path);
             rootLength = getRootLength(path);

src/compiler/declarationEmitter.ts

@@ -712,7 +712,12 @@ namespace ts {
         function writeModuleDeclaration(node: ModuleDeclaration) {
             emitJsDocComments(node);
             emitModuleElementDeclarationFlags(node);
-            write("module ");
+            if (node.flags & NodeFlags.Namespace) {
+                write("namespace ");
+            }
+            else {
+                write("module ");
+            }
             writeTextOfNode(currentSourceFile, node.name);
             while (node.body.kind !== SyntaxKind.ModuleBlock) {
                 node = <ModuleDeclaration>node.body;

src/compiler/diagnosticInformationMap.generated.ts

@@ -389,9 +389,9 @@ namespace ts {
         No_best_common_type_exists_among_yield_expressions: { code: 2504, category: DiagnosticCategory.Error, key: "No best common type exists among yield expressions." },
         A_generator_cannot_have_a_void_type_annotation: { code: 2505, category: DiagnosticCategory.Error, key: "A generator cannot have a 'void' type annotation." },
         _0_is_referenced_directly_or_indirectly_in_its_own_base_expression: { code: 2506, category: DiagnosticCategory.Error, key: "'{0}' is referenced directly or indirectly in its own base expression." },
-        Base_expression_is_not_of_a_constructor_function_type: { code: 2507, category: DiagnosticCategory.Error, key: "Base expression is not of a constructor function type." },
+        Type_0_is_not_a_constructor_function_type: { code: 2507, category: DiagnosticCategory.Error, key: "Type '{0}' is not a constructor function type." },
         No_base_constructor_has_the_specified_number_of_type_arguments: { code: 2508, category: DiagnosticCategory.Error, key: "No base constructor has the specified number of type arguments." },
-        Base_constructor_does_not_return_a_class_or_interface_type: { code: 2509, category: DiagnosticCategory.Error, key: "Base constructor does not return a class or interface type." },
+        Base_constructor_return_type_0_is_not_a_class_or_interface_type: { code: 2509, category: DiagnosticCategory.Error, key: "Base constructor return type '{0}' is not a class or interface type." },
         Base_constructors_must_all_have_the_same_return_type: { code: 2510, category: DiagnosticCategory.Error, key: "Base constructors must all have the same return type." },
         Cannot_create_an_instance_of_the_abstract_class_0: { code: 2511, category: DiagnosticCategory.Error, key: "Cannot create an instance of the abstract class '{0}'." },
         All_overload_signatures_must_match_with_respect_to_modifier_0: { code: 2512, category: DiagnosticCategory.Error, key: "All overload signatures must match with respect to modifier '{0}'." },

src/compiler/diagnosticMessages.json

@@ -1543,7 +1543,7 @@
         "category": "Error",
         "code": 2506
     },
-    "Base expression is not of a constructor function type.": {
+    "Type '{0}' is not a constructor function type.": {
         "category": "Error",
         "code": 2507
     },
@@ -1551,7 +1551,7 @@
         "category": "Error",
         "code": 2508
     },
-    "Base constructor does not return a class or interface type.": {
+    "Base constructor return type '{0}' is not a class or interface type.": {
         "category": "Error",
         "code": 2509
     },

src/compiler/emitter.ts

@@ -21,8 +21,7 @@ namespace 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };`;
 
         // emit output for the __decorate helper function
@@ -320,7 +319,7 @@ var __param = (this && this.__param) || function (paramIndex, decorator) {
 
                     let prevEncodedEmittedColumn = lastEncodedSourceMapSpan.emittedColumn;
                     // Line/Comma delimiters
-                    if (lastEncodedSourceMapSpan.emittedLine == lastRecordedSourceMapSpan.emittedLine) {
+                    if (lastEncodedSourceMapSpan.emittedLine === lastRecordedSourceMapSpan.emittedLine) {
                         // Emit comma to separate the entry
                         if (sourceMapData.sourceMapMappings) {
                             sourceMapData.sourceMapMappings += ",";
@@ -403,8 +402,8 @@ var __param = (this && this.__param) || function (paramIndex, decorator) {
 
                     // If this location wasn't recorded or the location in source is going backwards, record the span
                     if (!lastRecordedSourceMapSpan ||
-                        lastRecordedSourceMapSpan.emittedLine != emittedLine ||
-                        lastRecordedSourceMapSpan.emittedColumn != emittedColumn ||
+                        lastRecordedSourceMapSpan.emittedLine !== emittedLine ||
+                        lastRecordedSourceMapSpan.emittedColumn !== emittedColumn ||
                         (lastRecordedSourceMapSpan.sourceIndex === sourceMapSourceIndex &&
                             (lastRecordedSourceMapSpan.sourceLine > sourceLinePos.line ||
                                 (lastRecordedSourceMapSpan.sourceLine === sourceLinePos.line && lastRecordedSourceMapSpan.sourceColumn > sourceLinePos.character)))) {
@@ -654,7 +653,7 @@ var __param = (this && this.__param) || function (paramIndex, decorator) {
                         if (nodeIsSynthesized(node)) {
                             return emitNodeWithoutSourceMap(node);
                         }
-                        if (node.kind != SyntaxKind.SourceFile) {
+                        if (node.kind !== SyntaxKind.SourceFile) {
                             recordEmitNodeStartSpan(node);
                             emitNodeWithoutSourceMap(node);
                             recordEmitNodeEndSpan(node);
@@ -1962,7 +1961,7 @@ var __param = (this && this.__param) || function (paramIndex, decorator) {
 
                         // Make sure we consider all nested cast expressions, e.g.:
                         // (<any><number><any>-A).x;
-                        while (operand.kind == SyntaxKind.TypeAssertionExpression) {
+                        while (operand.kind === SyntaxKind.TypeAssertionExpression) {
                             operand = (<TypeAssertion>operand).expression;
                         }
 
@@ -5348,7 +5347,7 @@ var __param = (this && this.__param) || function (paramIndex, decorator) {
                 decreaseIndent();
                 writeLine();
                 write("}"); // return
-                emitTempDeclarations(/*newLine*/ true)
+                emitTempDeclarations(/*newLine*/ true);
             }
 
             function emitSetters(exportStarFunction: string) {

src/compiler/parser.ts

@@ -1491,12 +1491,20 @@ namespace ts {
                 switch (node.kind) {
                     case SyntaxKind.Constructor:
                     case SyntaxKind.IndexSignature:
-                    case SyntaxKind.MethodDeclaration:
                     case SyntaxKind.GetAccessor:
                     case SyntaxKind.SetAccessor:
                     case SyntaxKind.PropertyDeclaration:
                     case SyntaxKind.SemicolonClassElement:
                         return true;
+                    case SyntaxKind.MethodDeclaration:
+                        // Method declarations are not necessarily reusable.  An object-literal
+                        // may have a method calls "constructor(...)" and we must reparse that
+                        // into an actual .ConstructorDeclaration.
+                        let methodDeclaration = <MethodDeclaration>node;
+                        let nameIsConstructor = methodDeclaration.name.kind === SyntaxKind.Identifier &&
+                            (<Identifier>methodDeclaration.name).originalKeywordKind === SyntaxKind.ConstructorKeyword;
+
+                        return !nameIsConstructor;
                 }
             }
 
@@ -3990,7 +3998,7 @@ namespace ts {
                         parseExportAssignment(fullStart, decorators, modifiers) :
                         parseExportDeclaration(fullStart, decorators, modifiers);
                 default:
-                    if (decorators) {
+                    if (decorators || modifiers) {
                         // We reached this point because we encountered decorators and/or modifiers and assumed a declaration
                         // would follow. For recovery and error reporting purposes, return an incomplete declaration.                        
                         let node = <Statement>createMissingNode(SyntaxKind.MissingDeclaration, /*reportAtCurrentPosition*/ true, Diagnostics.Declaration_expected);
@@ -4392,7 +4400,7 @@ namespace ts {
                 return parsePropertyOrMethodDeclaration(fullStart, decorators, modifiers);
             }
 
-            if (decorators) {
+            if (decorators || modifiers) {
                 // treat this as a property declaration with a missing name.
                 let name = <Identifier>createMissingNode(SyntaxKind.Identifier, /*reportAtCurrentPosition*/ true, Diagnostics.Declaration_expected);
                 return parsePropertyDeclaration(fullStart, decorators, modifiers, name, /*questionToken*/ undefined);

src/compiler/program.ts

@@ -105,7 +105,10 @@ namespace ts {
     }
 
     export function getPreEmitDiagnostics(program: Program, sourceFile?: SourceFile): Diagnostic[] {
-        let diagnostics = program.getSyntacticDiagnostics(sourceFile).concat(program.getGlobalDiagnostics()).concat(program.getSemanticDiagnostics(sourceFile));
+        let diagnostics = program.getOptionsDiagnostics().concat(
+                          program.getSyntacticDiagnostics(sourceFile),
+                          program.getGlobalDiagnostics(),
+                          program.getSemanticDiagnostics(sourceFile));
 
         if (program.getCompilerOptions().declaration) {
             diagnostics.concat(program.getDeclarationDiagnostics(sourceFile));
@@ -144,7 +147,7 @@ namespace ts {
         let program: Program;
         let files: SourceFile[] = [];
         let diagnostics = createDiagnosticCollection();
-
+
         let commonSourceDirectory: string;
         let diagnosticsProducingTypeChecker: TypeChecker;
         let noDiagnosticsTypeChecker: TypeChecker;
@@ -177,10 +180,10 @@ namespace ts {
             getSourceFiles: () => files,
             getCompilerOptions: () => options,
             getSyntacticDiagnostics,
+            getOptionsDiagnostics,
             getGlobalDiagnostics,
             getSemanticDiagnostics,
             getDeclarationDiagnostics,
-            getCompilerOptionsDiagnostics,
             getTypeChecker,
             getClassifiableNames,
             getDiagnosticsProducingTypeChecker,
@@ -311,19 +314,15 @@ namespace ts {
             }
         }
 
-        function getCompilerOptionsDiagnostics(): Diagnostic[] {
+        function getOptionsDiagnostics(): Diagnostic[] {
             let allDiagnostics: Diagnostic[] = [];
             addRange(allDiagnostics, diagnostics.getGlobalDiagnostics());
             return sortAndDeduplicateDiagnostics(allDiagnostics);
         }
 
         function getGlobalDiagnostics(): Diagnostic[] {
-            let typeChecker = getDiagnosticsProducingTypeChecker();
-
             let allDiagnostics: Diagnostic[] = [];
-            addRange(allDiagnostics, typeChecker.getGlobalDiagnostics());
-            addRange(allDiagnostics, diagnostics.getGlobalDiagnostics());
-
+            addRange(allDiagnostics, getDiagnosticsProducingTypeChecker().getGlobalDiagnostics());
             return sortAndDeduplicateDiagnostics(allDiagnostics);
         }
 
@@ -678,4 +677,4 @@ namespace ts {
             }
         }
     }
-}
+}

src/compiler/scanner.ts

@@ -377,8 +377,31 @@ namespace ts {
         return ch >= CharacterCodes._0 && ch <= CharacterCodes._7;
     }
 
+    export function couldStartTrivia(text: string, pos: number): boolean {
+        // Keep in sync with skipTrivia
+        let ch = text.charCodeAt(pos);
+        switch (ch) {
+            case CharacterCodes.carriageReturn:
+            case CharacterCodes.lineFeed:
+            case CharacterCodes.tab:
+            case CharacterCodes.verticalTab:
+            case CharacterCodes.formFeed:
+            case CharacterCodes.space:
+            case CharacterCodes.slash:
+                // starts of normal trivia
+            case CharacterCodes.lessThan:
+            case CharacterCodes.equals:
+            case CharacterCodes.greaterThan:
+                // Starts of conflict marker trivia
+                return true;
+            default:
+                return ch > CharacterCodes.maxAsciiCharacter;
+        }
+    }
+
     /* @internal */ 
     export function skipTrivia(text: string, pos: number, stopAfterLineBreak?: boolean): number {
+        // Keep in sync with couldStartTrivia
         while (true) {
             let ch = text.charCodeAt(pos);
             switch (ch) {
@@ -935,7 +958,7 @@ namespace ts {
                 error(Diagnostics.Unexpected_end_of_text);
                 isInvalidExtendedEscape = true;
             }
-            else if (text.charCodeAt(pos) == CharacterCodes.closeBrace) {
+            else if (text.charCodeAt(pos) === CharacterCodes.closeBrace) {
                 // Only swallow the following character up if it's a '}'.
                 pos++;
             }

src/compiler/types.ts

@@ -1214,11 +1214,11 @@ namespace ts {
          */
         emit(targetSourceFile?: SourceFile, writeFile?: WriteFileCallback): EmitResult;
 
-        getSyntacticDiagnostics(sourceFile?: SourceFile): Diagnostic[];
+        getOptionsDiagnostics(): Diagnostic[];
         getGlobalDiagnostics(): Diagnostic[];
+        getSyntacticDiagnostics(sourceFile?: SourceFile): Diagnostic[];
         getSemanticDiagnostics(sourceFile?: SourceFile): Diagnostic[];
         getDeclarationDiagnostics(sourceFile?: SourceFile): Diagnostic[];
-        /* @internal */ getCompilerOptionsDiagnostics(): Diagnostic[];
 
         /** 
          * Gets a type checker that can be used to semantically analyze source fils in the program.

src/compiler/utilities.ts

@@ -42,7 +42,7 @@ namespace ts {
     // Pool writers to avoid needing to allocate them for every symbol we write.
     let stringWriters: StringSymbolWriter[] = [];
     export function getSingleLineStringWriter(): StringSymbolWriter {
-        if (stringWriters.length == 0) {
+        if (stringWriters.length === 0) {
             let str = "";
 
             let writeText: (text: string) => void = text => str += text;
@@ -426,7 +426,7 @@ namespace ts {
                 // Specialized signatures can have string literals as their parameters' type names
                 return node.parent.kind === SyntaxKind.Parameter;
             case SyntaxKind.ExpressionWithTypeArguments:
-                return !isClassExtendsExpressionWithTypeArguments(node);
+                return !isExpressionWithTypeArgumentsInClassExtendsClause(node);
 
             // Identifiers and qualified names may be type nodes, depending on their context. Climb
             // above them to find the lowest container
@@ -460,7 +460,7 @@ namespace ts {
                 }
                 switch (parent.kind) {
                     case SyntaxKind.ExpressionWithTypeArguments:
-                        return !isClassExtendsExpressionWithTypeArguments(parent);
+                        return !isExpressionWithTypeArgumentsInClassExtendsClause(parent);
                     case SyntaxKind.TypeParameter:
                         return node === (<TypeParameterDeclaration>parent).constraint;
                     case SyntaxKind.PropertyDeclaration:
@@ -920,7 +920,7 @@ namespace ts {
                     case SyntaxKind.Decorator:
                         return true;
                     case SyntaxKind.ExpressionWithTypeArguments:
-                        return isClassExtendsExpressionWithTypeArguments(parent);
+                        return (<ExpressionWithTypeArguments>parent).expression === node && isExpressionWithTypeArgumentsInClassExtendsClause(parent);
                     default:
                         if (isExpression(parent)) {
                             return true;
@@ -1916,7 +1916,7 @@ namespace ts {
         return token >= SyntaxKind.FirstAssignment && token <= SyntaxKind.LastAssignment;
     }
 
-    export function isClassExtendsExpressionWithTypeArguments(node: Node): boolean {
+    export function isExpressionWithTypeArgumentsInClassExtendsClause(node: Node): boolean {
         return node.kind === SyntaxKind.ExpressionWithTypeArguments &&
             (<HeritageClause>node.parent).token === SyntaxKind.ExtendsKeyword &&
             node.parent.parent.kind === SyntaxKind.ClassDeclaration;
@@ -2092,6 +2092,12 @@ namespace ts {
         return start <= textSpanEnd(span) && end >= span.start;
     }
 
+    export function decodedTextSpanIntersectsWith(start1: number, length1: number, start2: number, length2: number) {
+        let end1 = start1 + length1;
+        let end2 = start2 + length2;
+        return start2 <= end1 && end2 >= start1;
+    }
+
     export function textSpanIntersectsWithPosition(span: TextSpan, position: number) {
         return position <= textSpanEnd(span) && position >= span.start;
     }

src/harness/fourslash.ts

@@ -831,6 +831,7 @@ module FourSlash {
                 if (expectedText !== undefined) {
                     assert.notEqual(actualQuickInfoText, expectedText, this.messageAtLastKnownMarker("quick info text"));
                 }
+                // TODO: should be '==='?
                 if (expectedDocumentation != undefined) {
                     assert.notEqual(actualQuickInfoDocumentation, expectedDocumentation, this.messageAtLastKnownMarker("quick info doc comment"));
                 }
@@ -838,6 +839,7 @@ module FourSlash {
                 if (expectedText !== undefined) {
                     assert.equal(actualQuickInfoText, expectedText, this.messageAtLastKnownMarker("quick info text"));
                 }
+                // TODO: should be '==='?
                 if (expectedDocumentation != undefined) {
                     assert.equal(actualQuickInfoDocumentation, expectedDocumentation, assertionMessage("quick info doc"));
                 }
@@ -1820,7 +1822,7 @@ module FourSlash {
         }
 
         private verifyProjectInfo(expected: string[]) {
-            if (this.testType == FourSlashTestType.Server) {
+            if (this.testType === FourSlashTestType.Server) {
                 let actual = (<ts.server.SessionClient>this.languageService).getProjectInfo(
                     this.activeFile.fileName,
                     /* needFileNameList */ true
@@ -1937,7 +1939,7 @@ module FourSlash {
                 }
             }
 
-            if (expected != actual) {
+            if (expected !== actual) {
                 this.raiseError('verifyNavigationItemsCount failed - found: ' + actual + ' navigation items, expected: ' + expected + '.');
             }
         }
@@ -1984,7 +1986,7 @@ module FourSlash {
             var items = this.languageService.getNavigationBarItems(this.activeFile.fileName);
             var actual = this.getNavigationBarItemsCount(items);
 
-            if (expected != actual) {
+            if (expected !== actual) {
                 this.raiseError('verifyGetScriptLexicalStructureListCount failed - found: ' + actual + ' navigation items, expected: ' + expected + '.');
             }
         }
@@ -2402,6 +2404,7 @@ module FourSlash {
                         globalOptions[match[1]] = match[2];
                     }
                 }
+            // TODO: should be '==='?
             } else if (line == '' || lineLength === 0) {
                 // Previously blank lines between fourslash content caused it to be considered as 2 files,
                 // Remove this behavior since it just causes errors now

src/harness/harnessLanguageService.ts

@@ -583,7 +583,7 @@ module Harness.LanguageService {
             // This host is just a proxy for the clientHost, it uses the client
             // host to answer server queries about files on disk
             var serverHost = new SessionServerHost(clientHost);
-            var server = new ts.server.Session(serverHost, serverHost);
+            var server = new ts.server.Session(serverHost, Buffer.byteLength, process.hrtime, serverHost);
 
             // Fake the connection between the client and the server
             serverHost.writeMessage = client.onMessage.bind(client);

src/harness/projectsRunner.ts

@@ -110,6 +110,7 @@ class ProjectRunner extends RunnerBase {
                 else if (url.indexOf(diskProjectPath) === 0) {
                     // Replace the disk specific path into the project root path
                     url = url.substr(diskProjectPath.length);
+                    // TODO: should be '!=='?
                     if (url.charCodeAt(0) != ts.CharacterCodes.slash) {
                         url = "/" + url;
                     }
@@ -240,7 +241,7 @@ class ProjectRunner extends RunnerBase {
                 if (Harness.Compiler.isJS(fileName)) {
                     // Make sure if there is URl we have it cleaned up
                     var indexOfSourceMapUrl = data.lastIndexOf("//# sourceMappingURL=");
-                    if (indexOfSourceMapUrl != -1) {
+                    if (indexOfSourceMapUrl !== -1) {
                         data = data.substring(0, indexOfSourceMapUrl + 21) + cleanProjectUrl(data.substring(indexOfSourceMapUrl + 21));
                     }
                 }

src/harness/runner.ts

@@ -49,7 +49,6 @@ if (testConfigFile !== '') {
             if (!option) {
                 continue;
             }
-            ts.sys.write("Option: " + option + "\r\n");
             switch (option) {
                 case 'compiler':
                     runners.push(new CompilerBaselineRunner(CompilerTestType.Conformance));

src/harness/sourceMapRecorder.ts

@@ -46,7 +46,7 @@ module Harness.SourceMapRecoder {
         }
 
         function isSourceMappingSegmentEnd() {
-            if (decodingIndex == sourceMapMappings.length) {
+            if (decodingIndex === sourceMapMappings.length) {
                 return true;
             }
 
@@ -95,7 +95,7 @@ module Harness.SourceMapRecoder {
                     var currentByte = base64FormatDecode();
 
                     // If msb is set, we still have more bits to continue
-                    moreDigits = (currentByte & 32) != 0;
+                    moreDigits = (currentByte & 32) !== 0;
 
                     // least significant 5 bits are the next msbs in the final value.
                     value = value | ((currentByte & 31) << shiftCount);
@@ -103,7 +103,7 @@ module Harness.SourceMapRecoder {
                 }
 
                 // Least significant bit if 1 represents negative and rest of the msb is actual absolute value
-                if ((value & 1) == 0) {
+                if ((value & 1) === 0) {
                     // + number
                     value = value >> 1;
                 }
@@ -182,7 +182,7 @@ module Harness.SourceMapRecoder {
                     }
                 }
                 // Dont support reading mappings that dont have information about original source and its line numbers
-                if (createErrorIfCondition(!isSourceMappingSegmentEnd(), "Unsupported Error Format: There are more entries after " + (decodeOfEncodedMapping.nameIndex == -1 ? "sourceColumn" : "nameIndex"))) {
+                if (createErrorIfCondition(!isSourceMappingSegmentEnd(), "Unsupported Error Format: There are more entries after " + (decodeOfEncodedMapping.nameIndex === -1 ? "sourceColumn" : "nameIndex"))) {
                     return { error: errorDecodeOfEncodedMapping, sourceMapSpan: decodeOfEncodedMapping };
                 }
 
@@ -249,7 +249,7 @@ module Harness.SourceMapRecoder {
                 mapString += " name (" + sourceMapNames[mapEntry.nameIndex] + ")";
             }
             else {
-                if (mapEntry.nameIndex != -1 || getAbsentNameIndex) {
+                if (mapEntry.nameIndex !== -1 || getAbsentNameIndex) {
                     mapString += " nameIndex (" + mapEntry.nameIndex + ")";
                 }
             }
@@ -262,12 +262,12 @@ module Harness.SourceMapRecoder {
             var decodeResult = SourceMapDecoder.decodeNextEncodedSourceMapSpan();
             var decodedErrors: string[];
             if (decodeResult.error
-                || decodeResult.sourceMapSpan.emittedLine != sourceMapSpan.emittedLine
-                || decodeResult.sourceMapSpan.emittedColumn != sourceMapSpan.emittedColumn
-                || decodeResult.sourceMapSpan.sourceLine != sourceMapSpan.sourceLine
-                || decodeResult.sourceMapSpan.sourceColumn != sourceMapSpan.sourceColumn
-                || decodeResult.sourceMapSpan.sourceIndex != sourceMapSpan.sourceIndex
-                || decodeResult.sourceMapSpan.nameIndex != sourceMapSpan.nameIndex) {
+                || decodeResult.sourceMapSpan.emittedLine   !== sourceMapSpan.emittedLine
+                || decodeResult.sourceMapSpan.emittedColumn !== sourceMapSpan.emittedColumn
+                || decodeResult.sourceMapSpan.sourceLine    !== sourceMapSpan.sourceLine
+                || decodeResult.sourceMapSpan.sourceColumn  !== sourceMapSpan.sourceColumn
+                || decodeResult.sourceMapSpan.sourceIndex   !== sourceMapSpan.sourceIndex
+                || decodeResult.sourceMapSpan.nameIndex     !== sourceMapSpan.nameIndex) {
                 if (decodeResult.error) {
                     decodedErrors = ["!!^^ !!^^ There was decoding error in the sourcemap at this location: " + decodeResult.error];
                 }
@@ -288,7 +288,7 @@ module Harness.SourceMapRecoder {
         }
 
         export function recordNewSourceFileSpan(sourceMapSpan: ts.SourceMapSpan, newSourceFileCode: string) {
-            assert.isTrue(spansOnSingleLine.length == 0 || spansOnSingleLine[0].sourceMapSpan.emittedLine !== sourceMapSpan.emittedLine, "new file source map span should be on new line. We currently handle only that scenario");
+            assert.isTrue(spansOnSingleLine.length === 0 || spansOnSingleLine[0].sourceMapSpan.emittedLine !== sourceMapSpan.emittedLine, "new file source map span should be on new line. We currently handle only that scenario");
             recordSourceMapSpan(sourceMapSpan);
 
             assert.isTrue(spansOnSingleLine.length === 1);
@@ -395,9 +395,9 @@ module Harness.SourceMapRecoder {
 
                 var tsCodeLineMap = ts.computeLineStarts(sourceText);
                 for (var i = 0; i < tsCodeLineMap.length; i++) {
-                    writeSourceMapIndent(prevEmittedCol, i == 0 ? markerIds[index] : "  >");
+                    writeSourceMapIndent(prevEmittedCol, i === 0 ? markerIds[index] : "  >");
                     sourceMapRecoder.Write(getTextOfLine(i, tsCodeLineMap, sourceText));
-                    if (i == tsCodeLineMap.length - 1) {
+                    if (i === tsCodeLineMap.length - 1) {
                         sourceMapRecoder.WriteLine("");
                     }
                 }
@@ -447,7 +447,7 @@ module Harness.SourceMapRecoder {
             for (var j = 0; j < sourceMapData.sourceMapDecodedMappings.length; j++) {
                 var decodedSourceMapping = sourceMapData.sourceMapDecodedMappings[j];
                 var currentSourceFile = program.getSourceFile(sourceMapData.inputSourceFileNames[decodedSourceMapping.sourceIndex]);
-                if (currentSourceFile != prevSourceFile) {
+                if (currentSourceFile !== prevSourceFile) {
                     SourceMapSpanWriter.recordNewSourceFileSpan(decodedSourceMapping, currentSourceFile.text);
                     prevSourceFile = currentSourceFile;
                 }

src/harness/typeWriter.ts

@@ -43,7 +43,7 @@ class TypeWriterWalker {
 
         // Workaround to ensure we output 'C' instead of 'typeof C' for base class expressions
         // var type = this.checker.getTypeAtLocation(node);
-        var type = node.parent && ts.isClassExtendsExpressionWithTypeArguments(node.parent) && this.checker.getTypeAtLocation(node.parent) || this.checker.getTypeAtLocation(node);
+        var type = node.parent && ts.isExpressionWithTypeArgumentsInClassExtendsClause(node.parent) && this.checker.getTypeAtLocation(node.parent) || this.checker.getTypeAtLocation(node);
 
         ts.Debug.assert(type !== undefined, "type doesn't exist");
         var symbol = this.checker.getSymbolAtLocation(node);

src/lib/intl.d.ts

@@ -41,6 +41,11 @@ declare module Intl {
         currency?: string;
         currencyDisplay?: string;
         useGrouping?: boolean;
+        minimumintegerDigits?: number;
+        minimumFractionDigits?: number;
+        maximumFractionDigits?: number;
+        minimumSignificantDigits?: number;
+        maximumSignificantDigits?: number;
     }
 
     interface ResolvedNumberFormatOptions {
@@ -103,7 +108,7 @@ declare module Intl {
     }
 
     interface DateTimeFormat {
-        format(date: number): string;
+        format(date?: Date | number): string;
         resolvedOptions(): ResolvedDateTimeFormatOptions;
     }
     var DateTimeFormat: {

src/server/client.ts

@@ -219,7 +219,7 @@ namespace ts.server {
 
             var request = this.processRequest<protocol.CompletionDetailsRequest>(CommandNames.CompletionDetails, args);
             var response = this.processResponse<protocol.CompletionDetailsResponse>(request);
-            Debug.assert(response.body.length == 1, "Unexpected length of completion details response body.");
+            Debug.assert(response.body.length === 1, "Unexpected length of completion details response body.");
             return response.body[0];
         }
 
@@ -429,8 +429,8 @@ namespace ts.server {
             if (!this.lastRenameEntry ||
                 this.lastRenameEntry.fileName !== fileName ||
                 this.lastRenameEntry.position !== position ||
-                this.lastRenameEntry.findInStrings != findInStrings ||
-                this.lastRenameEntry.findInComments != findInComments) {
+                this.lastRenameEntry.findInStrings !== findInStrings ||
+                this.lastRenameEntry.findInComments !== findInComments) {
                 this.getRenameInfo(fileName, position, findInStrings, findInComments);
             }
 

src/server/editorServices.ts

@@ -2,7 +2,6 @@
 /// <reference path="..\services\services.ts" />
 /// <reference path="protocol.d.ts" />
 /// <reference path="session.ts" />
-/// <reference path="node.d.ts" />
 
 namespace ts.server {
     export interface Logger {
@@ -28,7 +27,7 @@ namespace ts.server {
         });
     }
 
-    class ScriptInfo {
+    export class ScriptInfo {
         svc: ScriptVersionCache;
         children: ScriptInfo[] = [];     // files referenced by this file
         defaultProject: Project;      // project to use by default for file
@@ -36,7 +35,7 @@ namespace ts.server {
         formatCodeOptions = ts.clone(CompilerService.defaultFormatCodeOptions);
 
         constructor(private host: ServerHost, public fileName: string, public content: string, public isOpen = false) {
-            this.svc = ScriptVersionCache.fromString(content);
+            this.svc = ScriptVersionCache.fromString(host, content);
         }
 
         setFormatOptions(formatOptions: protocol.FormatOptions): void {
@@ -80,7 +79,7 @@ namespace ts.server {
         }
     }
 
-    class LSHost implements ts.LanguageServiceHost {
+    export class LSHost implements ts.LanguageServiceHost {
         ls: ts.LanguageService = null;
         compilationSettings: ts.CompilerOptions;
         filenameToScript: ts.Map<ScriptInfo> = {};
@@ -273,7 +272,7 @@ namespace ts.server {
         }
     }
 
-    interface ProjectOptions {
+    export interface ProjectOptions {
         // these fields can be present in the project file
         files?: string[];
         compilerOptions?: ts.CompilerOptions;
@@ -376,7 +375,7 @@ namespace ts.server {
         }
     }
 
-    interface ProjectOpenResult {
+    export interface ProjectOpenResult {
         success?: boolean;
         errorMsg?: string;
         project?: Project;
@@ -392,11 +391,11 @@ namespace ts.server {
         return copiedList;
     }
 
-    interface ProjectServiceEventHandler {
+    export interface ProjectServiceEventHandler {
         (eventName: string, project: Project, fileName: string): void;
     }
 
-    interface HostConfiguration {
+    export interface HostConfiguration {
         formatCodeOptions: ts.FormatCodeOptions;
         hostInfo: string;
     }
@@ -629,7 +628,7 @@ namespace ts.server {
                 for (var i = 0, len = this.openFilesReferenced.length; i < len; i++) {
                     var f = this.openFilesReferenced[i];
                     // if f was referenced by the removed project, remember it
-                    if (f.defaultProject == removedProject) {
+                    if (f.defaultProject === removedProject) {
                         f.defaultProject = undefined;
                         orphanFiles.push(f);
                     }
@@ -656,7 +655,7 @@ namespace ts.server {
             for (var i = 0, len = this.inferredProjects.length; i < len; i++) {
                 var inferredProject = this.inferredProjects[i];
                 inferredProject.updateGraph();
-                if (inferredProject != excludedProject) {
+                if (inferredProject !== excludedProject) {
                     if (inferredProject.getSourceFile(info)) {
                         info.defaultProject = inferredProject;
                         referencingProjects.push(inferredProject);
@@ -710,7 +709,7 @@ namespace ts.server {
                 var rootFile = this.openFileRoots[i];
                 var rootedProject = rootFile.defaultProject;
                 var referencingProjects = this.findReferencingProjects(rootFile, rootedProject);
-                if (referencingProjects.length == 0) {
+                if (referencingProjects.length === 0) {
                     rootFile.defaultProject = rootedProject;
                     openFileRoots.push(rootFile);
                 }
@@ -916,7 +915,7 @@ namespace ts.server {
                 return rawConfig.error;
             }
             else {
-                var parsedCommandLine = ts.parseConfigFile(rawConfig.config, ts.sys, dirPath);
+                var parsedCommandLine = ts.parseConfigFile(rawConfig.config, this.host, dirPath);
                 if (parsedCommandLine.errors && (parsedCommandLine.errors.length > 0)) {
                     return { errorMsg: "tsconfig option errors" };
                 }
@@ -953,7 +952,7 @@ namespace ts.server {
 
     }
 
-    class CompilerService {
+    export class CompilerService {
         host: LSHost;
         languageService: ts.LanguageService;
         classifier: ts.Classifier;
@@ -985,7 +984,7 @@ namespace ts.server {
         static defaultFormatCodeOptions: ts.FormatCodeOptions = {
             IndentSize: 4,
             TabSize: 4,
-            NewLineCharacter: ts.sys.newLine,
+            NewLineCharacter: ts.sys ? ts.sys.newLine : '\n',
             ConvertTabsToSpaces: true,
             InsertSpaceAfterCommaDelimiter: true,
             InsertSpaceAfterSemicolonInForStatements: true,
@@ -999,7 +998,7 @@ namespace ts.server {
 
     }
 
-    interface LineCollection {
+    export interface LineCollection {
         charCount(): number;
         lineCount(): number;
         isLeaf(): boolean;
@@ -1013,7 +1012,7 @@ namespace ts.server {
         leaf?: LineLeaf;
     }
 
-    enum CharRangeSection {
+    export enum CharRangeSection {
         PreStart,
         Start,
         Entire,
@@ -1022,7 +1021,7 @@ namespace ts.server {
         PostEnd
     }
 
-    interface ILineIndexWalker {
+    export interface ILineIndexWalker {
         goSubtree: boolean;
         done: boolean;
         leaf(relativeStart: number, relativeLength: number, lineCollection: LineLeaf): void;
@@ -1082,7 +1081,7 @@ namespace ts.server {
 
             for (var k = this.endBranch.length - 1; k >= 0; k--) {
                 (<LineNode>this.endBranch[k]).updateCounts();
-                if (this.endBranch[k].charCount() == 0) {
+                if (this.endBranch[k].charCount() === 0) {
                     lastZeroCount = this.endBranch[k];
                     if (k > 0) {
                         branchParent = <LineNode>this.endBranch[k - 1];
@@ -1147,7 +1146,7 @@ namespace ts.server {
         post(relativeStart: number, relativeLength: number, lineCollection: LineCollection, parent: LineCollection, nodeType: CharRangeSection): LineCollection {
             // have visited the path for start of range, now looking for end
             // if range is on single line, we will never make this state transition
-            if (lineCollection == this.lineCollectionAtBranch) {
+            if (lineCollection === this.lineCollectionAtBranch) {
                 this.state = CharRangeSection.End;
             }
             // always pop stack because post only called when child has been visited
@@ -1159,7 +1158,7 @@ namespace ts.server {
             // currentNode corresponds to parent, but in the new tree
             var currentNode = this.stack[this.stack.length - 1];
 
-            if ((this.state == CharRangeSection.Entire) && (nodeType == CharRangeSection.Start)) {
+            if ((this.state === CharRangeSection.Entire) && (nodeType === CharRangeSection.Start)) {
                 // if range is on single line, we will never make this state transition
                 this.state = CharRangeSection.Start;
                 this.branchNode = currentNode;
@@ -1176,12 +1175,12 @@ namespace ts.server {
             switch (nodeType) {
                 case CharRangeSection.PreStart:
                     this.goSubtree = false;
-                    if (this.state != CharRangeSection.End) {
+                    if (this.state !== CharRangeSection.End) {
                         currentNode.add(lineCollection);
                     }
                     break;
                 case CharRangeSection.Start:
-                    if (this.state == CharRangeSection.End) {
+                    if (this.state === CharRangeSection.End) {
                         this.goSubtree = false;
                     }
                     else {
@@ -1191,7 +1190,7 @@ namespace ts.server {
                     }
                     break;
                 case CharRangeSection.Entire:
-                    if (this.state != CharRangeSection.End) {
+                    if (this.state !== CharRangeSection.End) {
                         child = fresh(lineCollection);
                         currentNode.add(child);
                         this.startPath[this.startPath.length] = child;
@@ -1208,7 +1207,7 @@ namespace ts.server {
                     this.goSubtree = false;
                     break;
                 case CharRangeSection.End:
-                    if (this.state != CharRangeSection.End) {
+                    if (this.state !== CharRangeSection.End) {
                         this.goSubtree = false;
                     }
                     else {
@@ -1221,7 +1220,7 @@ namespace ts.server {
                     break;
                 case CharRangeSection.PostEnd:
                     this.goSubtree = false;
-                    if (this.state != CharRangeSection.Start) {
+                    if (this.state !== CharRangeSection.Start) {
                         currentNode.add(lineCollection);
                     }
                     break;
@@ -1233,10 +1232,10 @@ namespace ts.server {
         }
         // just gather text from the leaves
         leaf(relativeStart: number, relativeLength: number, ll: LineLeaf) {
-            if (this.state == CharRangeSection.Start) {
+            if (this.state === CharRangeSection.Start) {
                 this.initialText = ll.text.substring(0, relativeStart);
             }
-            else if (this.state == CharRangeSection.Entire) {
+            else if (this.state === CharRangeSection.Entire) {
                 this.initialText = ll.text.substring(0, relativeStart);
                 this.trailingText = ll.text.substring(relativeStart + relativeLength);
             }
@@ -1248,7 +1247,7 @@ namespace ts.server {
     }
 
     // text change information
-    class TextChange {
+    export class TextChange {
         constructor(public pos: number, public deleteLen: number, public insertedText?: string) {
         }
 
@@ -1263,6 +1262,7 @@ namespace ts.server {
         versions: LineIndexSnapshot[] = [];
         minVersion = 0;  // no versions earlier than min version will maintain change history
         private currentVersion = 0;
+        private host: ServerHost;
 
         static changeNumberThreshold = 8;
         static changeLengthThreshold = 256;
@@ -1290,7 +1290,7 @@ namespace ts.server {
         }
 
         reloadFromFile(filename: string, cb?: () => any) {
-            var content = ts.sys.readFile(filename);
+            var content = this.host.readFile(filename);
             this.reload(content);
             if (cb)
                 cb();
@@ -1360,10 +1360,11 @@ namespace ts.server {
             }
         }
 
-        static fromString(script: string) {
+        static fromString(host: ServerHost, script: string) {
             var svc = new ScriptVersionCache();
             var snap = new LineIndexSnapshot(0, svc);
             svc.versions[svc.currentVersion] = snap;
+            svc.host = host;
             snap.index = new LineIndex();
             var lm = LineIndex.linesFromText(script);
             snap.index.load(lm.lines);
@@ -1371,7 +1372,7 @@ namespace ts.server {
         }
     }
 
-    class LineIndexSnapshot implements ts.IScriptSnapshot {
+    export class LineIndexSnapshot implements ts.IScriptSnapshot {
         index: LineIndex;
         changesSincePreviousVersion: TextChange[] = [];
 
@@ -1499,8 +1500,8 @@ namespace ts.server {
             function editFlat(source: string, s: number, dl: number, nt = "") {
                 return source.substring(0, s) + nt + source.substring(s + dl, source.length);
             }
-            if (this.root.charCount() == 0) {
-                // TODO: assert deleteLength == 0
+            if (this.root.charCount() === 0) {
+                // TODO: assert deleteLength === 0
                 if (newText) {
                     this.load(LineIndex.linesFromText(newText).lines);
                     return this;
@@ -1528,7 +1529,7 @@ namespace ts.server {
                     // check whether last characters deleted are line break
                     var e = pos + deleteLength;
                     var lineInfo = this.charOffsetToLineNumberAndPos(e);
-                    if ((lineInfo && (lineInfo.offset == 0))) {
+                    if ((lineInfo && (lineInfo.offset === 0))) {
                         // move range end just past line that will merge with previous line
                         deleteLength += lineInfo.text.length;
                         // store text by appending to end of insertedText
@@ -1574,7 +1575,7 @@ namespace ts.server {
                 interiorNodes[i].totalChars = charCount;
                 interiorNodes[i].totalLines = lineCount;
             }
-            if (interiorNodes.length == 1) {
+            if (interiorNodes.length === 1) {
                 return interiorNodes[0];
             }
             else {
@@ -1585,7 +1586,7 @@ namespace ts.server {
         static linesFromText(text: string) {
             var lineStarts = ts.computeLineStarts(text);
 
-            if (lineStarts.length == 0) {
+            if (lineStarts.length === 0) {
                 return { lines: <string[]>[], lineMap: lineStarts };
             }
             var lines = <string[]>new Array(lineStarts.length);
@@ -1605,7 +1606,7 @@ namespace ts.server {
         }
     }
 
-    class LineNode implements LineCollection {
+    export class LineNode implements LineCollection {
         totalChars = 0;
         totalLines = 0;
         children: LineCollection[] = [];
@@ -1821,7 +1822,7 @@ namespace ts.server {
         findChildIndex(child: LineCollection) {
             var childIndex = 0;
             var clen = this.children.length;
-            while ((this.children[childIndex] != child) && (childIndex < clen)) childIndex++;
+            while ((this.children[childIndex] !== child) && (childIndex < clen)) childIndex++;
             return childIndex;
         }
 
@@ -1830,7 +1831,7 @@ namespace ts.server {
             var clen = this.children.length;
             var nodeCount = nodes.length;
             // if child is last and there is more room and only one node to place, place it
-            if ((clen < lineCollectionCapacity) && (childIndex == (clen - 1)) && (nodeCount == 1)) {
+            if ((clen < lineCollectionCapacity) && (childIndex === (clen - 1)) && (nodeCount === 1)) {
                 this.add(nodes[0]);
                 this.updateCounts();
                 return [];
@@ -1854,13 +1855,13 @@ namespace ts.server {
                     var splitNode = <LineNode>splitNodes[0];
                     while (nodeIndex < nodeCount) {
                         splitNode.add(nodes[nodeIndex++]);
-                        if (splitNode.children.length == lineCollectionCapacity) {
+                        if (splitNode.children.length === lineCollectionCapacity) {
                             splitNodeIndex++;
                             splitNode = <LineNode>splitNodes[splitNodeIndex];
                         }
                     }
                     for (i = splitNodes.length - 1; i >= 0; i--) {
-                        if (splitNodes[i].children.length == 0) {
+                        if (splitNodes[i].children.length === 0) {
                             splitNodes.length--;
                         }
                     }
@@ -1891,7 +1892,7 @@ namespace ts.server {
         }
     }
 
-    class LineLeaf implements LineCollection {
+    export class LineLeaf implements LineCollection {
         udata: any;
 
         constructor(public text: string) {

src/server/node.d.ts

@@ -584,9 +584,9 @@ declare module NodeJS {
         export interface Response extends Message {
             request_seq: number;
             success: boolean;
-            /** Contains error message if success == false. */
+            /** Contains error message if success === false. */
             message?: string;
-            /** Contains message body if success == true. */
+            /** Contains message body if success === true. */
             body?: any;
         }
 

src/server/protocol.d.ts

@@ -67,12 +67,12 @@ declare namespace ts.server.protocol {
         command: string;
 
         /** 
-          * Contains error message if success == false. 
+          * Contains error message if success === false. 
           */
         message?: string;
 
         /**
-          * Contains message body if success == true.
+          * Contains message body if success === true.
           */
         body?: any;
     }

src/server/server.ts

@@ -11,7 +11,7 @@ namespace ts.server {
         input: process.stdin,
         output: process.stdout,
         terminal: false,
-    });
+    });  
 
     class Logger implements ts.server.Logger {
         fd = -1;
@@ -123,7 +123,7 @@ namespace ts.server {
                 if (err) {
                     watchedFile.callback(watchedFile.fileName);
                 }
-                else if (watchedFile.mtime.getTime() != stats.mtime.getTime()) {
+                else if (watchedFile.mtime.getTime() !== stats.mtime.getTime()) {
                     watchedFile.mtime = WatchedFileSet.getModifiedTime(watchedFile.fileName);
                     watchedFile.callback(watchedFile.fileName);
                 }
@@ -138,7 +138,7 @@ namespace ts.server {
                 var count = 0;
                 var nextToCheck = this.nextFileToCheck;
                 var firstCheck = -1;
-                while ((count < this.chunkSize) && (nextToCheck != firstCheck)) {
+                while ((count < this.chunkSize) && (nextToCheck !== firstCheck)) {
                     this.poll(nextToCheck);
                     if (firstCheck < 0) {
                         firstCheck = nextToCheck;
@@ -170,11 +170,11 @@ namespace ts.server {
         removeFile(file: WatchedFile) {
             this.watchedFiles = WatchedFileSet.copyListRemovingItem(file, this.watchedFiles);
         }
-    }
+    } 
 
     class IOSession extends Session {
         constructor(host: ServerHost, logger: ts.server.Logger) {
-            super(host, logger);
+            super(host, Buffer.byteLength, process.hrtime, logger);
         }
 
         exit() {

src/server/session.ts

@@ -1,6 +1,5 @@
 /// <reference path="..\compiler\commandLineParser.ts" />
 /// <reference path="..\services\services.ts" />
-/// <reference path="node.d.ts" />
 /// <reference path="protocol.d.ts" />
 /// <reference path="editorServices.ts" />
 
@@ -31,7 +30,7 @@ namespace ts.server {
         if (a < b) {
             return -1;
         }
-        else if (a == b) {
+        else if (a === b) {
             return 0;
         }
         else return 1;
@@ -43,7 +42,7 @@ namespace ts.server {
         }
         else if (a.file == b.file) {
             var n = compareNumber(a.start.line, b.start.line);
-            if (n == 0) {
+            if (n === 0) {
                 return compareNumber(a.start.offset, b.start.offset);
             }
             else return n;
@@ -61,7 +60,7 @@ namespace ts.server {
         };
     }
 
-    interface PendingErrorCheck {
+    export interface PendingErrorCheck {
         fileName: string;
         project: Project;
     }
@@ -114,11 +113,16 @@ namespace ts.server {
         pendingOperation = false;
         fileHash: ts.Map<number> = {};
         nextFileId = 1;
-        errorTimer: NodeJS.Timer;
+        errorTimer: any; /*NodeJS.Timer | number*/
         immediateId: any;
         changeSeq = 0;
 
-        constructor(private host: ServerHost, private logger: Logger) {
+        constructor(
+            private host: ServerHost, 
+            private byteLength: (buf: string, encoding?: string) => number, 
+            private hrtime: (start?: number[]) => number[], 
+            private logger: Logger
+        ) {
             this.projectService =
                 new ProjectService(host, logger, (eventName,project,fileName) => {
                 this.handleEvent(eventName, project, fileName);
@@ -129,7 +133,7 @@ namespace ts.server {
             if (eventName == "context") {
                 this.projectService.log("got context event, updating diagnostics for" + fileName, "Info");
                 this.updateErrorCheck([{ fileName, project }], this.changeSeq,
-                    (n) => n == this.changeSeq, 100);
+                    (n) => n === this.changeSeq, 100);
             }
         }
 
@@ -149,17 +153,17 @@ namespace ts.server {
             this.host.write(line + this.host.newLine);
         }
 
-        send(msg: NodeJS._debugger.Message) {
+        send(msg: protocol.Message) {
             var json = JSON.stringify(msg);
             if (this.logger.isVerbose()) {
                 this.logger.info(msg.type + ": " + json);
             }
-            this.sendLineToClient('Content-Length: ' + (1 + Buffer.byteLength(json, 'utf8')) +
+            this.sendLineToClient('Content-Length: ' + (1 + this.byteLength(json, 'utf8')) +
                 '\r\n\r\n' + json);
         }
 
         event(info: any, eventName: string) {
-            var ev: NodeJS._debugger.Event = {
+            var ev: protocol.Event = {
                 seq: 0,
                 type: "event",
                 event: eventName,
@@ -546,7 +550,7 @@ namespace ts.server {
             // getFormattingEditsAfterKeytroke either empty or pertaining
             // only to the previous line.  If all this is true, then
             // add edits necessary to properly indent the current line.
-            if ((key == "\n") && ((!edits) || (edits.length == 0) || allEditsBeforePos(edits, position))) {
+            if ((key == "\n") && ((!edits) || (edits.length === 0) || allEditsBeforePos(edits, position))) {
                 var scriptInfo = compilerService.host.getScriptInfo(file);
                 if (scriptInfo) {
                     var lineInfo = scriptInfo.getLineInfo(line);
@@ -622,7 +626,7 @@ namespace ts.server {
             }
 
             return completions.entries.reduce((result: protocol.CompletionEntry[], entry: ts.CompletionEntry) => {
-                if (completions.isMemberCompletion || (entry.name.toLowerCase().indexOf(prefix.toLowerCase()) == 0)) {
+                if (completions.isMemberCompletion || (entry.name.toLowerCase().indexOf(prefix.toLowerCase()) === 0)) {
                     result.push(entry);
                 }
                 return result;
@@ -689,7 +693,7 @@ namespace ts.server {
             }, []);
 
             if (checkList.length > 0) {
-                this.updateErrorCheck(checkList, this.changeSeq,(n) => n == this.changeSeq, delay)
+                this.updateErrorCheck(checkList, this.changeSeq,(n) => n === this.changeSeq, delay)
             }
         }
 
@@ -704,7 +708,7 @@ namespace ts.server {
                     compilerService.host.editScript(file, start, end, insertString);
                     this.changeSeq++;
                 }
-                this.updateProjectStructure(this.changeSeq, (n) => n == this.changeSeq);
+                this.updateProjectStructure(this.changeSeq, (n) => n === this.changeSeq);
             }
         }
 
@@ -838,7 +842,7 @@ namespace ts.server {
         onMessage(message: string) {
             if (this.logger.isVerbose()) {
                 this.logger.info("request: " + message);
-                var start = process.hrtime();                
+                var start = this.hrtime();                
             }
             try {
                 var request = <protocol.Request>JSON.parse(message);
@@ -980,7 +984,7 @@ namespace ts.server {
                 }
 
                 if (this.logger.isVerbose()) {
-                    var elapsed = process.hrtime(start);
+                    var elapsed = this.hrtime(start);
                     var seconds = elapsed[0]
                     var nanoseconds = elapsed[1];
                     var elapsedMs = ((1e9 * seconds) + nanoseconds)/1000000.0;

src/services/breakpoints.ts

@@ -75,7 +75,7 @@ namespace ts.BreakpointResolver {
                         return textSpan(node);
                     }
 
-                    if (node.parent.kind == SyntaxKind.ArrowFunction && (<FunctionLikeDeclaration>node.parent).body == node) {
+                    if (node.parent.kind === SyntaxKind.ArrowFunction && (<FunctionLikeDeclaration>node.parent).body === node) {
                         // If this is body of arrow function, it is allowed to have the breakpoint
                         return textSpan(node);
                     }

src/services/formatting/formattingContext.ts

@@ -59,7 +59,7 @@ namespace ts.formatting {
             if (this.tokensAreOnSameLine === undefined) {
                 let startLine = this.sourceFile.getLineAndCharacterOfPosition(this.currentTokenSpan.pos).line;
                 let endLine = this.sourceFile.getLineAndCharacterOfPosition(this.nextTokenSpan.pos).line;
-                this.tokensAreOnSameLine = (startLine == endLine);
+                this.tokensAreOnSameLine = (startLine === endLine);
             }
 
             return this.tokensAreOnSameLine;
@@ -84,7 +84,7 @@ namespace ts.formatting {
         private NodeIsOnOneLine(node: Node): boolean {
             let startLine = this.sourceFile.getLineAndCharacterOfPosition(node.getStart(this.sourceFile)).line;
             let endLine = this.sourceFile.getLineAndCharacterOfPosition(node.getEnd()).line;
-            return startLine == endLine;
+            return startLine === endLine;
         }
 
         private BlockIsOnOneLine(node: Node): boolean {

src/services/formatting/ruleOperationContext.ts

@@ -14,7 +14,7 @@ namespace ts.formatting {
 
 
         public IsAny(): boolean {
-            return this == RuleOperationContext.Any;
+            return this === RuleOperationContext.Any;
         }
 
         public  InContext(context: FormattingContext): boolean {

src/services/formatting/rules.ts

@@ -692,7 +692,7 @@ namespace ts.formatting {
         }
 
         static IsNotFormatOnEnter(context: FormattingContext): boolean {
-            return context.formattingRequestKind != FormattingRequestKind.FormatOnEnter;
+            return context.formattingRequestKind !== FormattingRequestKind.FormatOnEnter;
         }
 
         static IsModuleDeclContext(context: FormattingContext): boolean {

src/services/formatting/rulesMap.ts

@@ -41,15 +41,15 @@ namespace ts.formatting {
         }
 
         private FillRule(rule: Rule, rulesBucketConstructionStateList: RulesBucketConstructionState[]): void {
-            let specificRule = rule.Descriptor.LeftTokenRange != Shared.TokenRange.Any &&
-                               rule.Descriptor.RightTokenRange != Shared.TokenRange.Any;
+            let specificRule = rule.Descriptor.LeftTokenRange !== Shared.TokenRange.Any &&
+                               rule.Descriptor.RightTokenRange !== Shared.TokenRange.Any;
 
             rule.Descriptor.LeftTokenRange.GetTokens().forEach((left) => {
                 rule.Descriptor.RightTokenRange.GetTokens().forEach((right) => {
                     let rulesBucketIndex = this.GetRuleBucketIndex(left, right);
 
                     let rulesBucket = this.map[rulesBucketIndex];
-                    if (rulesBucket == undefined) {
+                    if (rulesBucket === undefined) {
                         rulesBucket = this.map[rulesBucketIndex] = new RulesBucket();
                     }
 
@@ -124,7 +124,7 @@ namespace ts.formatting {
         public IncreaseInsertionIndex(maskPosition: RulesPosition): void {
             let value = (this.rulesInsertionIndexBitmap >> maskPosition) & Mask;
             value++;
-            Debug.assert((value & Mask) == value, "Adding more rules into the sub-bucket than allowed. Maximum allowed is 32 rules.");
+            Debug.assert((value & Mask) === value, "Adding more rules into the sub-bucket than allowed. Maximum allowed is 32 rules.");
 
             let temp = this.rulesInsertionIndexBitmap & ~(Mask << maskPosition);
             temp |= value << maskPosition;
@@ -147,7 +147,7 @@ namespace ts.formatting {
         public AddRule(rule: Rule, specificTokens: boolean, constructionState: RulesBucketConstructionState[], rulesBucketIndex: number): void {
             let position: RulesPosition;
 
-            if (rule.Operation.Action == RuleAction.Ignore) {
+            if (rule.Operation.Action === RuleAction.Ignore) {
                 position = specificTokens ?
                     RulesPosition.IgnoreRulesSpecific :
                     RulesPosition.IgnoreRulesAny;

src/services/formatting/rulesProvider.ts

@@ -25,6 +25,7 @@ namespace ts.formatting {
         }
 
         public ensureUpToDate(options: ts.FormatCodeOptions) {
+            // TODO: Should this be '==='?
             if (this.options == null || !ts.compareDataObjects(this.options, options)) {
                 let activeRules = this.createActiveRules(options);
                 let rulesMap = RulesMap.create(activeRules);

src/services/formatting/tokenRange.ts

@@ -54,7 +54,7 @@ namespace ts.formatting {
             }
 
             public Contains(tokenValue: SyntaxKind): boolean {
-                return tokenValue == this.token;
+                return tokenValue === this.token;
             }
         }
 

src/services/patternMatcher.ts

@@ -686,7 +686,7 @@ namespace ts {
 
             if (charIsPunctuation(identifier.charCodeAt(i - 1)) ||
                 charIsPunctuation(identifier.charCodeAt(i)) ||
-                lastIsDigit != currentIsDigit ||
+                lastIsDigit !== currentIsDigit ||
                 hasTransitionFromLowerToUpper ||
                 hasTransitionFromUpperToLower) {
 
@@ -757,7 +757,7 @@ namespace ts {
             // 3) HTMLDocument -> HTML, Document
             //
             // etc.
-            if (index != wordStart &&
+            if (index !== wordStart &&
                 index + 1 < identifier.length) {
                 let currentIsUpper = isUpperCaseLetter(identifier.charCodeAt(index));
                 let nextIsLower = isLowerCaseLetter(identifier.charCodeAt(index + 1));

src/services/services.ts

@@ -167,7 +167,7 @@ namespace ts {
         }
 
         public getFullWidth(): number {
-            return this.end - this.getFullStart();
+            return this.end - this.pos;
         }
 
         public getLeadingTriviaWidth(sourceFile?: SourceFile): number {
@@ -973,6 +973,9 @@ namespace ts {
 
         getSyntacticDiagnostics(fileName: string): Diagnostic[];
         getSemanticDiagnostics(fileName: string): Diagnostic[];
+
+        // TODO: Rename this to getProgramDiagnostics to better indicate that these are any
+        // diagnostics present for the program level, and not just 'options' diagnostics.
         getCompilerOptionsDiagnostics(): Diagnostic[];
 
         /** 
@@ -1790,11 +1793,6 @@ namespace ts {
             sourceFile.moduleName = moduleName;
         }
 
-        // Store syntactic diagnostics
-        if (diagnostics && sourceFile.parseDiagnostics) {
-            diagnostics.push(...sourceFile.parseDiagnostics);
-        }
-
         let newLine = getNewLineCharacter(options);
 
         // Output
@@ -1816,9 +1814,8 @@ namespace ts {
 
         var program = createProgram([inputFileName], options, compilerHost);
 
-        if (diagnostics) {
-            diagnostics.push(...program.getCompilerOptionsDiagnostics());
-        }
+        addRange(/*to*/ diagnostics, /*from*/ program.getSyntacticDiagnostics(sourceFile));
+        addRange(/*to*/ diagnostics, /*from*/ program.getOptionsDiagnostics());
 
         // Emit
         program.emit();
@@ -2798,7 +2795,7 @@ namespace ts {
 
         function getCompilerOptionsDiagnostics() {
             synchronizeHostData();
-            return program.getGlobalDiagnostics();
+            return program.getOptionsDiagnostics().concat(program.getGlobalDiagnostics());
         }
 
         /// Completion
@@ -4190,7 +4187,7 @@ namespace ts {
                 var result: DefinitionInfo[] = [];
                 forEach((<UnionType>type).types, t => {
                     if (t.symbol) {
-                        result.push(...getDefinitionFromSymbol(t.symbol, node));
+                        addRange(/*to*/ result, /*from*/ getDefinitionFromSymbol(t.symbol, node));
                     }
                 });
                 return result;
@@ -5814,7 +5811,7 @@ namespace ts {
             }
 
             return node.parent.kind === SyntaxKind.TypeReference ||
-                (node.parent.kind === SyntaxKind.ExpressionWithTypeArguments && !isClassExtendsExpressionWithTypeArguments(<ExpressionWithTypeArguments>node.parent));
+                (node.parent.kind === SyntaxKind.ExpressionWithTypeArguments && !isExpressionWithTypeArgumentsInClassExtendsClause(<ExpressionWithTypeArguments>node.parent));
         }
 
         function isNamespaceReference(node: Node): boolean {
@@ -6046,7 +6043,8 @@ namespace ts {
                  */
                 function hasValueSideModule(symbol: Symbol): boolean {
                     return forEach(symbol.declarations, declaration => {
-                        return declaration.kind === SyntaxKind.ModuleDeclaration && getModuleInstanceState(declaration) == ModuleInstanceState.Instantiated;
+                        return declaration.kind === SyntaxKind.ModuleDeclaration && 
+                            getModuleInstanceState(declaration) === ModuleInstanceState.Instantiated;
                     });
                 }
             }
@@ -6119,6 +6117,8 @@ namespace ts {
         function getEncodedSyntacticClassifications(fileName: string, span: TextSpan): Classifications {
             // doesn't use compiler - no need to synchronize with host
             let sourceFile = syntaxTreeCache.getCurrentSourceFile(fileName);
+            let spanStart = span.start;
+            let spanLength = span.length;
 
             // Make a scanner we can get trivia from.
             let triviaScanner = createScanner(ScriptTarget.Latest, /*skipTrivia:*/ false, sourceFile.text);
@@ -6135,48 +6135,55 @@ namespace ts {
                 result.push(type);
             }
 
-            function classifyLeadingTrivia(token: Node): void {
-                let tokenStart = skipTrivia(sourceFile.text, token.pos, /*stopAfterLineBreak:*/ false);
-                if (tokenStart === token.pos) {
-                    return;
-                }
-
-                // token has trivia.  Classify them appropriately.
+            function classifyLeadingTriviaAndGetTokenStart(token: Node): number {
                 triviaScanner.setTextPos(token.pos);
                 while (true) {
                     let start = triviaScanner.getTextPos();
+                    // only bother scanning if we have something that could be trivia.
+                    if (!couldStartTrivia(sourceFile.text, start)) {
+                        return start;
+                    }
+
                     let kind = triviaScanner.scan();
                     let end = triviaScanner.getTextPos();
                     let width = end - start;
 
                     // The moment we get something that isn't trivia, then stop processing.
                     if (!isTrivia(kind)) {
-                        return;
+                        return start;
+                    }
+
+                    // Don't bother with newlines/whitespace.
+                    if (kind === SyntaxKind.NewLineTrivia || kind === SyntaxKind.WhitespaceTrivia) {
+                        continue;
                     }
 
                     // Only bother with the trivia if it at least intersects the span of interest.
-                    if (textSpanIntersectsWith(span, start, width)) {
-                        if (isComment(kind)) {
-                            classifyComment(token, kind, start, width);
+                    if (isComment(kind)) {
+                        classifyComment(token, kind, start, width);
+                            
+                        // Classifying a comment might cause us to reuse the trivia scanner 
+                        // (because of jsdoc comments).  So after we classify the comment make
+                        // sure we set the scanner position back to where it needs to be.
+                        triviaScanner.setTextPos(end);
+                        continue;
+                    }
+
+                    if (kind === SyntaxKind.ConflictMarkerTrivia) {
+                        let text = sourceFile.text;
+                        let ch = text.charCodeAt(start);
+
+                        // for the <<<<<<< and >>>>>>> markers, we just add them in as comments
+                        // in the classification stream.
+                        if (ch === CharacterCodes.lessThan || ch === CharacterCodes.greaterThan) {
+                            pushClassification(start, width, ClassificationType.comment);
                             continue;
                         }
 
-                        if (kind === SyntaxKind.ConflictMarkerTrivia) {
-                            let text = sourceFile.text;
-                            let ch = text.charCodeAt(start);
-
-                            // for the <<<<<<< and >>>>>>> markers, we just add them in as comments
-                            // in the classification stream.
-                            if (ch === CharacterCodes.lessThan || ch === CharacterCodes.greaterThan) {
-                                pushClassification(start, width, ClassificationType.comment);
-                                continue;
-                            }
-
-                            // for the ======== add a comment for the first line, and then lex all
-                            // subsequent lines up until the end of the conflict marker.
-                            Debug.assert(ch === CharacterCodes.equals);
-                            classifyDisabledMergeCode(text, start, end);
-                        }
+                        // for the ======== add a comment for the first line, and then lex all
+                        // subsequent lines up until the end of the conflict marker.
+                        Debug.assert(ch === CharacterCodes.equals);
+                        classifyDisabledMergeCode(text, start, end);
                     }
                 }
             }
@@ -6295,12 +6302,14 @@ namespace ts {
             }
 
             function classifyToken(token: Node): void {
-                classifyLeadingTrivia(token);
+                let tokenStart = classifyLeadingTriviaAndGetTokenStart(token);
 
-                if (token.getWidth() > 0) {
+                let tokenWidth = token.end - tokenStart;
+                Debug.assert(tokenWidth >= 0);
+                if (tokenWidth > 0) {
                     let type = classifyTokenType(token.kind, token);
                     if (type) {
-                        pushClassification(token.getStart(), token.getWidth(), type);
+                        pushClassification(tokenStart, tokenWidth, type);
                     }
                 }
             }
@@ -6405,9 +6414,10 @@ namespace ts {
                 }
 
                 // Ignore nodes that don't intersect the original span to classify.
-                if (textSpanIntersectsWith(span, element.getFullStart(), element.getFullWidth())) {
+                if (decodedTextSpanIntersectsWith(spanStart, spanLength, element.pos, element.getFullWidth())) {
                     let children = element.getChildren(sourceFile);
-                    for (let child of children) {
+                    for (let i = 0, n = children.length; i < n; i++) {
+                        let child = children[i];
                         if (isToken(child)) {
                             classifyToken(child);
                         }

src/services/shims.ts

@@ -234,6 +234,7 @@ namespace ts {
         public getChangeRange(oldSnapshot: IScriptSnapshot): TextChangeRange {
             var oldSnapshotShim = <ScriptSnapshotShimAdapter>oldSnapshot;
             var encoded = this.scriptSnapshotShim.getChangeRange(oldSnapshotShim.scriptSnapshotShim);
+            // TODO: should this be '==='?
             if (encoded == null) {
                 return null;
             }
@@ -283,6 +284,7 @@ namespace ts {
 
         public getCompilationSettings(): CompilerOptions {
             var settingsJson = this.shimHost.getCompilationSettings();
+            // TODO: should this be '==='?
             if (settingsJson == null || settingsJson == "") {
                 throw Error("LanguageServiceShimHostAdapter.getCompilationSettings: empty compilationSettings");
                 return null;

tests/baselines/reference/ExportClassWithAccessibleTypesInTypeParameterConstraintsClassHeritageListMemberTypeAnnotations.js

@@ -24,8 +24,7 @@ module A {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var A;
 (function (A) {

tests/baselines/reference/ExportClassWithInaccessibleTypeInTypeParameterConstraint.js

@@ -28,8 +28,7 @@ module A {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var A;
 (function (A) {

tests/baselines/reference/accessOverriddenBaseClassMember1.js

@@ -19,8 +19,7 @@ class ColoredPoint extends Point {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Point = (function () {
     function Point(x, y) {

tests/baselines/reference/accessors_spec_section-4.5_inference.js

@@ -28,8 +28,7 @@ class LanguageSpec_section_4_5_inference {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var A = (function () {
     function A() {

tests/baselines/reference/aliasUsageInAccessorsOfClass.js

@@ -38,8 +38,7 @@ exports.Model = Model;
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Backbone = require("aliasUsage1_backbone");
 var VisualizationModel = (function (_super) {

tests/baselines/reference/aliasUsageInArray.js

@@ -32,8 +32,7 @@ exports.Model = Model;
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Backbone = require("aliasUsageInArray_backbone");
 var VisualizationModel = (function (_super) {

tests/baselines/reference/aliasUsageInFunctionExpression.js

@@ -31,8 +31,7 @@ exports.Model = Model;
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Backbone = require("aliasUsageInFunctionExpression_backbone");
 var VisualizationModel = (function (_super) {

tests/baselines/reference/aliasUsageInGenericFunction.js

@@ -35,8 +35,7 @@ exports.Model = Model;
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Backbone = require("aliasUsageInGenericFunction_backbone");
 var VisualizationModel = (function (_super) {

tests/baselines/reference/aliasUsageInIndexerOfClass.js

@@ -37,8 +37,7 @@ exports.Model = Model;
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Backbone = require("aliasUsageInIndexerOfClass_backbone");
 var VisualizationModel = (function (_super) {

tests/baselines/reference/aliasUsageInObjectLiteral.js

@@ -32,8 +32,7 @@ exports.Model = Model;
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Backbone = require("aliasUsageInObjectLiteral_backbone");
 var VisualizationModel = (function (_super) {

tests/baselines/reference/aliasUsageInOrExpression.js

@@ -35,8 +35,7 @@ exports.Model = Model;
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Backbone = require("aliasUsageInOrExpression_backbone");
 var VisualizationModel = (function (_super) {

tests/baselines/reference/aliasUsageInTypeArgumentOfExtendsClause.js

@@ -35,8 +35,7 @@ exports.Model = Model;
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Backbone = require("aliasUsageInTypeArgumentOfExtendsClause_backbone");
 var VisualizationModel = (function (_super) {
@@ -51,8 +50,7 @@ exports.VisualizationModel = VisualizationModel;
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var moduleA = require("aliasUsageInTypeArgumentOfExtendsClause_moduleA");
 var C = (function () {

tests/baselines/reference/aliasUsageInVarAssignment.js

@@ -31,8 +31,7 @@ exports.Model = Model;
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Backbone = require("aliasUsageInVarAssignment_backbone");
 var VisualizationModel = (function (_super) {

tests/baselines/reference/ambiguousOverloadResolution.js

@@ -12,8 +12,7 @@ var t: number = f(x, x); // Not an error
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var A = (function () {
     function A() {

tests/baselines/reference/apparentTypeSubtyping.js

@@ -27,8 +27,7 @@ class Derived2<U extends String> extends Base2 { // error because of the prototy
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Base = (function () {
     function Base() {

tests/baselines/reference/apparentTypeSupertype.js

@@ -17,8 +17,7 @@ class Derived<U extends String> extends Base { // error
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Base = (function () {
     function Base() {

tests/baselines/reference/arrayAssignmentTest1.js

@@ -89,8 +89,7 @@ arr_any = i1; // should be an error - is
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var C1 = (function () {
     function C1() {

tests/baselines/reference/arrayAssignmentTest2.js

@@ -63,8 +63,7 @@ arr_any = i1; // should be an error - is
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var C1 = (function () {
     function C1() {

tests/baselines/reference/arrayBestCommonTypes.js

@@ -111,8 +111,7 @@ module NonEmptyTypes {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var EmptyTypes;
 (function (EmptyTypes) {

tests/baselines/reference/arrayLiteralTypeInference.js

@@ -55,8 +55,7 @@ var z3: { id: number }[] =
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Action = (function () {
     function Action() {

tests/baselines/reference/arrayLiterals.js

@@ -41,8 +41,7 @@ var context4: Base[] = [new Derived1(), new Derived1()];
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var arr1 = [[], [1], ['']];
 var arr2 = [[null], [1], ['']];

tests/baselines/reference/arrayLiteralsWithRecursiveGenerics.js

@@ -29,8 +29,7 @@ var as = [list, myDerivedList]; // List<number>[]
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var List = (function () {
     function List() {

tests/baselines/reference/arrowFunctionContexts.js

@@ -100,8 +100,7 @@ var asserted2: any;
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 // Arrow function used in with statement
 with (window) {

tests/baselines/reference/assignmentCompatWithCallSignatures3.js

@@ -104,8 +104,7 @@ b18 = a18; // ok
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Base = (function () {
     function Base() {

tests/baselines/reference/assignmentCompatWithCallSignatures4.js

@@ -103,8 +103,7 @@ module Errors {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Errors;
 (function (Errors) {

tests/baselines/reference/assignmentCompatWithCallSignatures5.js

@@ -70,8 +70,7 @@ b18 = a18; // ok
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Base = (function () {
     function Base() {

tests/baselines/reference/assignmentCompatWithCallSignatures6.js

@@ -47,8 +47,7 @@ b16 = x.a16;
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Base = (function () {
     function Base() {

tests/baselines/reference/assignmentCompatWithConstructSignatures3.js

@@ -104,8 +104,7 @@ b18 = a18; // ok
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Base = (function () {
     function Base() {

tests/baselines/reference/assignmentCompatWithConstructSignatures4.js

@@ -103,8 +103,7 @@ module Errors {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Errors;
 (function (Errors) {

tests/baselines/reference/assignmentCompatWithConstructSignatures5.js

@@ -70,8 +70,7 @@ b18 = a18; // ok
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Base = (function () {
     function Base() {

tests/baselines/reference/assignmentCompatWithConstructSignatures6.js

@@ -47,8 +47,7 @@ b16 = x.a16;
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Base = (function () {
     function Base() {

tests/baselines/reference/assignmentCompatWithNumericIndexer.js

@@ -48,8 +48,7 @@ module Generics {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var A = (function () {
     function A() {

tests/baselines/reference/assignmentCompatWithNumericIndexer3.js

@@ -45,8 +45,7 @@ module Generics {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var A = (function () {
     function A() {

tests/baselines/reference/assignmentCompatWithObjectMembers4.js

@@ -96,8 +96,7 @@ module WithBase {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var OnlyDerived;
 (function (OnlyDerived) {

tests/baselines/reference/assignmentCompatWithObjectMembersOptionality.js

@@ -93,8 +93,7 @@ module SourceHasOptional {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Base = (function () {
     function Base() {

tests/baselines/reference/assignmentCompatWithObjectMembersOptionality2.js

@@ -95,8 +95,7 @@ module SourceHasOptional {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Base = (function () {
     function Base() {

tests/baselines/reference/assignmentCompatWithStringIndexer.js

@@ -58,8 +58,7 @@ module Generics {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var A = (function () {
     function A() {

tests/baselines/reference/assignmentLHSIsValue.js

@@ -74,8 +74,7 @@ foo() = value;
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 // expected error for all the LHS of assignments
 var value;

tests/baselines/reference/autolift4.js

@@ -27,8 +27,7 @@ class Point3D extends Point {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Point = (function () {
     function Point(x, y) {

tests/baselines/reference/baseCheck.js

@@ -33,8 +33,7 @@ function f() {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var C = (function () {
     function C(x, y) {

tests/baselines/reference/baseIndexSignatureResolution.js

@@ -28,8 +28,7 @@ var z: Derived = b.foo();
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Base = (function () {
     function Base() {

tests/baselines/reference/baseTypeOrderChecking.js

@@ -40,8 +40,7 @@ class Class4<T> extends Class3<T>
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var someVariable;
 var Class1 = (function () {

tests/baselines/reference/baseTypeWrappingInstantiationChain.js

@@ -30,8 +30,7 @@ class Wrapper<T5> {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var C = (function (_super) {
     __extends(C, _super);

tests/baselines/reference/bases.js

@@ -24,8 +24,7 @@ new C().y;
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var B = (function () {
     function B() {

tests/baselines/reference/bestCommonTypeOfConditionalExpressions.js

@@ -32,8 +32,7 @@ function foo5<T, U>(t: T, u: U): Object {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var a;
 var b;

tests/baselines/reference/bestCommonTypeOfConditionalExpressions2.js

@@ -30,8 +30,7 @@ function foo3<T extends U, U extends V, V>(t: T, u: U) {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Base = (function () {
     function Base() {

tests/baselines/reference/bestCommonTypeOfTuple2.js

@@ -26,8 +26,7 @@ var e51 = t5[2]; // {}
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var C = (function () {
     function C() {

tests/baselines/reference/callSignatureAssignabilityInInheritance2.js

@@ -74,8 +74,7 @@ interface I extends A {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Base = (function () {
     function Base() {

tests/baselines/reference/callSignatureAssignabilityInInheritance3.js

@@ -119,8 +119,7 @@ module Errors {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Errors;
 (function (Errors) {

tests/baselines/reference/callSignatureAssignabilityInInheritance4.js

@@ -54,8 +54,7 @@ interface I extends A {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Base = (function () {
     function Base() {

tests/baselines/reference/callSignatureAssignabilityInInheritance5.js

@@ -54,8 +54,7 @@ interface I extends B {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Base = (function () {
     function Base() {

tests/baselines/reference/callSignatureAssignabilityInInheritance6.js

@@ -57,8 +57,7 @@ interface I9<T> extends A {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Base = (function () {
     function Base() {

tests/baselines/reference/callWithSpread.js

@@ -54,8 +54,7 @@ class D extends C {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 function foo(x, y) {
     var z = [];

tests/baselines/reference/captureThisInSuperCall.js

@@ -12,8 +12,7 @@ class B extends A {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var A = (function () {
     function A(p) {

tests/baselines/reference/castingTuple.js

@@ -36,8 +36,7 @@ t4[2] = 10;
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var A = (function () {
     function A() {

tests/baselines/reference/chainedAssignment3.js

@@ -26,8 +26,7 @@ a = b = new A();
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var A = (function () {
     function A() {

tests/baselines/reference/chainedCallsWithTypeParameterConstrainedToOtherTypeParameter.js

@@ -23,8 +23,7 @@ class C extends B {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Chain = (function () {
     function Chain(value) {

tests/baselines/reference/checkForObjectTooStrict.js

@@ -35,8 +35,7 @@ class Baz extends Object {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var Foo;
 (function (Foo) {

tests/baselines/reference/circularImportAlias.js

@@ -24,8 +24,7 @@ var c = new B.a.C();
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var B;
 (function (B) {

tests/baselines/reference/classConstructorParametersAccessibility.js

@@ -30,8 +30,7 @@ class Derived extends C3 {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var C1 = (function () {
     function C1(x) {

tests/baselines/reference/classConstructorParametersAccessibility2.js

@@ -30,8 +30,7 @@ class Derived extends C3 {
 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; }
-    __.prototype = b.prototype;
-    d.prototype = new __();
+    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
 };
 var C1 = (function () {
     function C1(x) {