Merge pull request #20380 from Microsoft/literalContexts

Fewer intermediate object literal and array literal types

src/compiler/checker.ts

@@ -10677,7 +10677,7 @@ namespace ts {
         }
 
         function getWidenedLiteralLikeTypeForContextualType(type: Type, contextualType: Type) {
-            if (!isLiteralLikeContextualType(contextualType)) {
+            if (!isLiteralOfContextualType(type, contextualType)) {
                 type = getWidenedUniqueESSymbolType(getWidenedLiteralType(type));
             }
             return type;
@@ -18960,19 +18960,33 @@ namespace ts {
                 isTypeAssertion(declaration.initializer) ? type : getWidenedLiteralType(type);
         }
 
-        function isLiteralLikeContextualType(contextualType: Type) {
+        function isLiteralOfContextualType(candidateType: Type, contextualType: Type): boolean {
             if (contextualType) {
-                if (contextualType.flags & TypeFlags.TypeVariable) {
-                    const constraint = getBaseConstraintOfType(contextualType) || emptyObjectType;
-                    // If the type parameter is constrained to the base primitive type we're checking for,
-                    // consider this a literal context. For example, given a type parameter 'T extends string',
-                    // this causes us to infer string literal types for T.
-                    if (constraint.flags & (TypeFlags.String | TypeFlags.Number | TypeFlags.Boolean | TypeFlags.Enum | TypeFlags.ESSymbol)) {
-                        return true;
-                    }
-                    contextualType = constraint;
+                if (contextualType.flags & TypeFlags.Union && !(contextualType.flags & TypeFlags.Boolean)) {
+                    // If the contextual type is a union containing both of the 'true' and 'false' types we
+                    // don't consider it a literal context for boolean literals.
+                    const types = (<UnionType>contextualType).types;
+                    return some(types, t =>
+                        !(t.flags & TypeFlags.BooleanLiteral && containsType(types, trueType) && containsType(types, falseType)) &&
+                        isLiteralOfContextualType(candidateType, t));
                 }
-                return maybeTypeOfKind(contextualType, (TypeFlags.Literal | TypeFlags.Index | TypeFlags.UniqueESSymbol));
+                if (contextualType.flags & TypeFlags.TypeVariable) {
+                    // If the contextual type is a type variable constrained to a primitive type, consider
+                    // this a literal context for literals of that primitive type. For example, given a
+                    // type parameter 'T extends string', infer string literal types for T.
+                    const constraint = getBaseConstraintOfType(contextualType) || emptyObjectType;
+                    return constraint.flags & TypeFlags.String && maybeTypeOfKind(candidateType, TypeFlags.StringLiteral) ||
+                        constraint.flags & TypeFlags.Number && maybeTypeOfKind(candidateType, TypeFlags.NumberLiteral) ||
+                        constraint.flags & TypeFlags.Boolean && maybeTypeOfKind(candidateType, TypeFlags.BooleanLiteral) ||
+                        constraint.flags & TypeFlags.ESSymbol && maybeTypeOfKind(candidateType, TypeFlags.UniqueESSymbol) ||
+                        isLiteralOfContextualType(candidateType, constraint);
+                }
+                // If the contextual type is a literal of a particular primitive type, we consider this a
+                // literal context for all literals of that primitive type.
+                return contextualType.flags & (TypeFlags.StringLiteral | TypeFlags.Index) && maybeTypeOfKind(candidateType, TypeFlags.StringLiteral) ||
+                    contextualType.flags & TypeFlags.NumberLiteral && maybeTypeOfKind(candidateType, TypeFlags.NumberLiteral) ||
+                    contextualType.flags & TypeFlags.BooleanLiteral && maybeTypeOfKind(candidateType, TypeFlags.BooleanLiteral) ||
+                    contextualType.flags & TypeFlags.UniqueESSymbol && maybeTypeOfKind(candidateType, TypeFlags.UniqueESSymbol);
             }
             return false;
         }

tests/baselines/reference/argumentExpressionContextualTyping.types

@@ -51,13 +51,13 @@ var o1: { x: [string, number], y: { c: boolean, d: string, e: number } } = { x:
 >c : boolean
 >d : string
 >e : number
->{ x: ["string", 1], y: { c: true, d: "world", e: 3 } } : { x: [string, number]; y: { c: true; d: string; e: number; }; }
+>{ x: ["string", 1], y: { c: true, d: "world", e: 3 } } : { x: [string, number]; y: { c: boolean; d: string; e: number; }; }
 >x : [string, number]
 >["string", 1] : [string, number]
 >"string" : "string"
 >1 : 1
->y : { c: true; d: string; e: number; }
->{ c: true, d: "world", e: 3 } : { c: true; d: string; e: number; }
+>y : { c: boolean; d: string; e: number; }
+>{ c: true, d: "world", e: 3 } : { c: boolean; d: string; e: number; }
 >c : boolean
 >true : true
 >d : string
@@ -96,7 +96,7 @@ var array = ["string", 1, true];
 
 var tuple: [string, number, boolean] = ["string", 1, true];
 >tuple : [string, number, boolean]
->["string", 1, true] : [string, number, true]
+>["string", 1, true] : [string, number, boolean]
 >"string" : "string"
 >1 : 1
 >true : true
@@ -109,7 +109,7 @@ baz(tuple);
 baz(["string", 1, true]);
 >baz(["string", 1, true]) : void
 >baz : (x: [string, number, boolean]) => void
->["string", 1, true] : [string, number, true]
+>["string", 1, true] : [string, number, boolean]
 >"string" : "string"
 >1 : 1
 >true : true

tests/baselines/reference/arrayBestCommonTypes.types

@@ -255,14 +255,14 @@ module EmptyTypes {
 >x : boolean
 >y : base
 >base : base
->[{ x: true, y: new derived() }, { x: false, y: new base() }] : ({ x: true; y: derived; } | { x: false; y: base; })[]
->{ x: true, y: new derived() } : { x: true; y: derived; }
+>[{ x: true, y: new derived() }, { x: false, y: new base() }] : { x: boolean; y: derived; }[]
+>{ x: true, y: new derived() } : { x: boolean; y: derived; }
 >x : boolean
 >true : true
 >y : derived
 >new derived() : derived
 >derived : typeof derived
->{ x: false, y: new base() } : { x: false; y: base; }
+>{ x: false, y: new base() } : { x: boolean; y: base; }
 >x : boolean
 >false : false
 >y : base
@@ -658,14 +658,14 @@ module NonEmptyTypes {
 >x : boolean
 >y : base
 >base : base
->[{ x: true, y: new derived() }, { x: false, y: new base() }] : ({ x: true; y: derived; } | { x: false; y: base; })[]
->{ x: true, y: new derived() } : { x: true; y: derived; }
+>[{ x: true, y: new derived() }, { x: false, y: new base() }] : { x: boolean; y: base; }[]
+>{ x: true, y: new derived() } : { x: boolean; y: derived; }
 >x : boolean
 >true : true
 >y : derived
 >new derived() : derived
 >derived : typeof derived
->{ x: false, y: new base() } : { x: false; y: base; }
+>{ x: false, y: new base() } : { x: boolean; y: base; }
 >x : boolean
 >false : false
 >y : base

tests/baselines/reference/arrayLiterals3.errors.txt

@@ -1,7 +1,7 @@
 tests/cases/conformance/expressions/arrayLiterals/arrayLiterals3.ts(10,5): error TS2322: Type 'undefined[]' is not assignable to type '[any, any, any]'.
   Property '0' is missing in type 'undefined[]'.
-tests/cases/conformance/expressions/arrayLiterals/arrayLiterals3.ts(11,5): error TS2322: Type '["string", number, boolean]' is not assignable to type '[boolean, string, number]'.
-  Type '"string"' is not assignable to type 'boolean'.
+tests/cases/conformance/expressions/arrayLiterals/arrayLiterals3.ts(11,5): error TS2322: Type '[string, number, boolean]' is not assignable to type '[boolean, string, number]'.
+  Type 'string' is not assignable to type 'boolean'.
 tests/cases/conformance/expressions/arrayLiterals/arrayLiterals3.ts(17,5): error TS2322: Type '[number, number, string, boolean]' is not assignable to type '[number, number]'.
   Types of property 'length' are incompatible.
     Type '4' is not assignable to type '2'.
@@ -34,8 +34,8 @@ tests/cases/conformance/expressions/arrayLiterals/arrayLiterals3.ts(34,5): error
 !!! error TS2322:   Property '0' is missing in type 'undefined[]'.
     var a1: [boolean, string, number] = ["string", 1, true];  // Error
         ~~
-!!! error TS2322: Type '["string", number, boolean]' is not assignable to type '[boolean, string, number]'.
-!!! error TS2322:   Type '"string"' is not assignable to type 'boolean'.
+!!! error TS2322: Type '[string, number, boolean]' is not assignable to type '[boolean, string, number]'.
+!!! error TS2322:   Type 'string' is not assignable to type 'boolean'.
     
     // The resulting type an array literal expression is determined as follows:
     //     - If the array literal contains no spread elements and is an array assignment pattern in a destructuring assignment (section 4.17.1),

tests/baselines/reference/arrayLiterals3.types

@@ -14,7 +14,7 @@ var a0: [any, any, any] = [];                             // Error
 
 var a1: [boolean, string, number] = ["string", 1, true];  // Error
 >a1 : [boolean, string, number]
->["string", 1, true] : ["string", number, boolean]
+>["string", 1, true] : [string, number, boolean]
 >"string" : "string"
 >1 : 1
 >true : true

tests/baselines/reference/assignToFn.types

@@ -13,9 +13,9 @@ module M {
     var x:I={ f:function(n) { return true; } };
 >x : I
 >I : I
->{ f:function(n) { return true; } } : { f: (n: number) => true; }
->f : (n: number) => true
->function(n) { return true; } : (n: number) => true
+>{ f:function(n) { return true; } } : { f: (n: number) => boolean; }
+>f : (n: number) => boolean
+>function(n) { return true; } : (n: number) => boolean
 >n : number
 >true : true
 

tests/baselines/reference/assignmentTypeNarrowing.types

@@ -12,14 +12,14 @@ x; // string
 >x : string
 
 [x] = [true];
->[x] = [true] : [true]
+>[x] = [true] : [boolean]
 >[x] : [string | number | boolean | RegExp]
 >x : string | number | boolean | RegExp
->[true] : [true]
+>[true] : [boolean]
 >true : true
 
 x; // boolean
->x : true
+>x : boolean
 
 [x = ""] = [1];
 >[x = ""] = [1] : [number]
@@ -34,24 +34,24 @@ x; // string | number
 >x : string | number
 
 ({x} = {x: true});
->({x} = {x: true}) : { x: true; }
->{x} = {x: true} : { x: true; }
+>({x} = {x: true}) : { x: boolean; }
+>{x} = {x: true} : { x: boolean; }
 >{x} : { x: string | number | boolean | RegExp; }
 >x : string | number | boolean | RegExp
->{x: true} : { x: true; }
+>{x: true} : { x: boolean; }
 >x : boolean
 >true : true
 
 x; // boolean
->x : true
+>x : boolean
 
 ({y: x} = {y: 1});
->({y: x} = {y: 1}) : { y: 1; }
->{y: x} = {y: 1} : { y: 1; }
+>({y: x} = {y: 1}) : { y: number; }
+>{y: x} = {y: 1} : { y: number; }
 >{y: x} : { y: string | number | boolean | RegExp; }
 >y : string | number | boolean | RegExp
 >x : string | number | boolean | RegExp
->{y: 1} : { y: 1; }
+>{y: 1} : { y: number; }
 >y : number
 >1 : 1
 
@@ -59,16 +59,16 @@ x; // number
 >x : number
 
 ({x = ""} = {x: true});
->({x = ""} = {x: true}) : { x?: true; }
->{x = ""} = {x: true} : { x?: true; }
+>({x = ""} = {x: true}) : { x?: boolean; }
+>{x = ""} = {x: true} : { x?: boolean; }
 >{x = ""} : { x?: string | number | boolean | RegExp; }
 >x : string | number | boolean | RegExp
->{x: true} : { x?: true; }
+>{x: true} : { x?: boolean; }
 >x : boolean
 >true : true
 
 x; // string | boolean
->x : string | true
+>x : string | boolean
 
 ({y: x = /a/} = {y: 1});
 >({y: x = /a/} = {y: 1}) : { y?: number; }

tests/baselines/reference/asyncFunctionReturnType.types

@@ -15,7 +15,7 @@ async function fAsyncExplicit(): Promise<[number, boolean]> {
 
     // This is contextually typed as a tuple.
     return [1, true];
->[1, true] : [number, true]
+>[1, true] : [number, boolean]
 >1 : 1
 >true : true
 }

tests/baselines/reference/computedPropertyNamesContextualType10_ES5.errors.txt

@@ -1,7 +1,7 @@
-tests/cases/conformance/es6/computedProperties/computedPropertyNamesContextualType10_ES5.ts(5,5): error TS2322: Type '{ [x: number]: "" | 0; }' is not assignable to type 'I'.
+tests/cases/conformance/es6/computedProperties/computedPropertyNamesContextualType10_ES5.ts(5,5): error TS2322: Type '{ [x: number]: string | number; }' is not assignable to type 'I'.
   Index signatures are incompatible.
-    Type '"" | 0' is not assignable to type 'boolean'.
-      Type '""' is not assignable to type 'boolean'.
+    Type 'string | number' is not assignable to type 'boolean'.
+      Type 'string' is not assignable to type 'boolean'.
 
 
 ==== tests/cases/conformance/es6/computedProperties/computedPropertyNamesContextualType10_ES5.ts (1 errors) ====
@@ -11,10 +11,10 @@ tests/cases/conformance/es6/computedProperties/computedPropertyNamesContextualTy
     
     var o: I = {
         ~
-!!! error TS2322: Type '{ [x: number]: "" | 0; }' is not assignable to type 'I'.
+!!! error TS2322: Type '{ [x: number]: string | number; }' is not assignable to type 'I'.
 !!! error TS2322:   Index signatures are incompatible.
-!!! error TS2322:     Type '"" | 0' is not assignable to type 'boolean'.
-!!! error TS2322:       Type '""' is not assignable to type 'boolean'.
+!!! error TS2322:     Type 'string | number' is not assignable to type 'boolean'.
+!!! error TS2322:       Type 'string' is not assignable to type 'boolean'.
         [+"foo"]: "",
         [+"bar"]: 0
     }

tests/baselines/reference/computedPropertyNamesContextualType10_ES5.types

@@ -9,7 +9,7 @@ interface I {
 var o: I = {
 >o : I
 >I : I
->{    [+"foo"]: "",    [+"bar"]: 0} : { [x: number]: "" | 0; }
+>{    [+"foo"]: "",    [+"bar"]: 0} : { [x: number]: string | number; }
 
     [+"foo"]: "",
 >+"foo" : number

tests/baselines/reference/computedPropertyNamesContextualType10_ES6.errors.txt

@@ -1,7 +1,7 @@
-tests/cases/conformance/es6/computedProperties/computedPropertyNamesContextualType10_ES6.ts(5,5): error TS2322: Type '{ [x: number]: "" | 0; }' is not assignable to type 'I'.
+tests/cases/conformance/es6/computedProperties/computedPropertyNamesContextualType10_ES6.ts(5,5): error TS2322: Type '{ [x: number]: string | number; }' is not assignable to type 'I'.
   Index signatures are incompatible.
-    Type '"" | 0' is not assignable to type 'boolean'.
-      Type '""' is not assignable to type 'boolean'.
+    Type 'string | number' is not assignable to type 'boolean'.
+      Type 'string' is not assignable to type 'boolean'.
 
 
 ==== tests/cases/conformance/es6/computedProperties/computedPropertyNamesContextualType10_ES6.ts (1 errors) ====
@@ -11,10 +11,10 @@ tests/cases/conformance/es6/computedProperties/computedPropertyNamesContextualTy
     
     var o: I = {
         ~
-!!! error TS2322: Type '{ [x: number]: "" | 0; }' is not assignable to type 'I'.
+!!! error TS2322: Type '{ [x: number]: string | number; }' is not assignable to type 'I'.
 !!! error TS2322:   Index signatures are incompatible.
-!!! error TS2322:     Type '"" | 0' is not assignable to type 'boolean'.
-!!! error TS2322:       Type '""' is not assignable to type 'boolean'.
+!!! error TS2322:     Type 'string | number' is not assignable to type 'boolean'.
+!!! error TS2322:       Type 'string' is not assignable to type 'boolean'.
         [+"foo"]: "",
         [+"bar"]: 0
     }

tests/baselines/reference/computedPropertyNamesContextualType10_ES6.types

@@ -9,7 +9,7 @@ interface I {
 var o: I = {
 >o : I
 >I : I
->{    [+"foo"]: "",    [+"bar"]: 0} : { [x: number]: "" | 0; }
+>{    [+"foo"]: "",    [+"bar"]: 0} : { [x: number]: string | number; }
 
     [+"foo"]: "",
 >+"foo" : number

tests/baselines/reference/computedPropertyNamesContextualType6_ES5.types

@@ -19,7 +19,7 @@ declare function foo<T>(obj: I<T>): T
 foo({
 >foo({    p: "",    0: () => { },    ["hi" + "bye"]: true,    [0 + 1]: 0,    [+"hi"]: [0]}) : string | number | boolean | (() => void) | number[]
 >foo : <T>(obj: I<T>) => T
->{    p: "",    0: () => { },    ["hi" + "bye"]: true,    [0 + 1]: 0,    [+"hi"]: [0]} : { [x: string]: true | "" | (() => void) | 0 | number[]; [x: number]: (() => void) | 0 | number[]; p: ""; 0: () => void; }
+>{    p: "",    0: () => { },    ["hi" + "bye"]: true,    [0 + 1]: 0,    [+"hi"]: [0]} : { [x: string]: string | number | boolean | (() => void) | number[]; [x: number]: number | (() => void) | number[]; p: string; 0: () => void; }
 
     p: "",
 >p : string

tests/baselines/reference/computedPropertyNamesContextualType6_ES6.types

@@ -19,7 +19,7 @@ declare function foo<T>(obj: I<T>): T
 foo({
 >foo({    p: "",    0: () => { },    ["hi" + "bye"]: true,    [0 + 1]: 0,    [+"hi"]: [0]}) : string | number | boolean | (() => void) | number[]
 >foo : <T>(obj: I<T>) => T
->{    p: "",    0: () => { },    ["hi" + "bye"]: true,    [0 + 1]: 0,    [+"hi"]: [0]} : { [x: string]: true | "" | (() => void) | 0 | number[]; [x: number]: (() => void) | 0 | number[]; p: ""; 0: () => void; }
+>{    p: "",    0: () => { },    ["hi" + "bye"]: true,    [0 + 1]: 0,    [+"hi"]: [0]} : { [x: string]: string | number | boolean | (() => void) | number[]; [x: number]: number | (() => void) | number[]; p: string; 0: () => void; }
 
     p: "",
 >p : string

tests/baselines/reference/computedPropertyNamesContextualType8_ES5.errors.txt

@@ -1,7 +1,7 @@
-tests/cases/conformance/es6/computedProperties/computedPropertyNamesContextualType8_ES5.ts(6,5): error TS2322: Type '{ [x: string]: "" | 0; }' is not assignable to type 'I'.
+tests/cases/conformance/es6/computedProperties/computedPropertyNamesContextualType8_ES5.ts(6,5): error TS2322: Type '{ [x: string]: string | number; }' is not assignable to type 'I'.
   Index signatures are incompatible.
-    Type '"" | 0' is not assignable to type 'boolean'.
-      Type '""' is not assignable to type 'boolean'.
+    Type 'string | number' is not assignable to type 'boolean'.
+      Type 'string' is not assignable to type 'boolean'.
 
 
 ==== tests/cases/conformance/es6/computedProperties/computedPropertyNamesContextualType8_ES5.ts (1 errors) ====
@@ -12,10 +12,10 @@ tests/cases/conformance/es6/computedProperties/computedPropertyNamesContextualTy
     
     var o: I = {
         ~
-!!! error TS2322: Type '{ [x: string]: "" | 0; }' is not assignable to type 'I'.
+!!! error TS2322: Type '{ [x: string]: string | number; }' is not assignable to type 'I'.
 !!! error TS2322:   Index signatures are incompatible.
-!!! error TS2322:     Type '"" | 0' is not assignable to type 'boolean'.
-!!! error TS2322:       Type '""' is not assignable to type 'boolean'.
+!!! error TS2322:     Type 'string | number' is not assignable to type 'boolean'.
+!!! error TS2322:       Type 'string' is not assignable to type 'boolean'.
         [""+"foo"]: "",
         [""+"bar"]: 0
     }

tests/baselines/reference/computedPropertyNamesContextualType8_ES5.types

@@ -12,7 +12,7 @@ interface I {
 var o: I = {
 >o : I
 >I : I
->{    [""+"foo"]: "",    [""+"bar"]: 0} : { [x: string]: "" | 0; }
+>{    [""+"foo"]: "",    [""+"bar"]: 0} : { [x: string]: string | number; }
 
     [""+"foo"]: "",
 >""+"foo" : string

tests/baselines/reference/computedPropertyNamesContextualType8_ES6.errors.txt

@@ -1,7 +1,7 @@
-tests/cases/conformance/es6/computedProperties/computedPropertyNamesContextualType8_ES6.ts(6,5): error TS2322: Type '{ [x: string]: "" | 0; }' is not assignable to type 'I'.
+tests/cases/conformance/es6/computedProperties/computedPropertyNamesContextualType8_ES6.ts(6,5): error TS2322: Type '{ [x: string]: string | number; }' is not assignable to type 'I'.
   Index signatures are incompatible.
-    Type '"" | 0' is not assignable to type 'boolean'.
-      Type '""' is not assignable to type 'boolean'.
+    Type 'string | number' is not assignable to type 'boolean'.
+      Type 'string' is not assignable to type 'boolean'.
 
 
 ==== tests/cases/conformance/es6/computedProperties/computedPropertyNamesContextualType8_ES6.ts (1 errors) ====
@@ -12,10 +12,10 @@ tests/cases/conformance/es6/computedProperties/computedPropertyNamesContextualTy
     
     var o: I = {
         ~
-!!! error TS2322: Type '{ [x: string]: "" | 0; }' is not assignable to type 'I'.
+!!! error TS2322: Type '{ [x: string]: string | number; }' is not assignable to type 'I'.
 !!! error TS2322:   Index signatures are incompatible.
-!!! error TS2322:     Type '"" | 0' is not assignable to type 'boolean'.
-!!! error TS2322:       Type '""' is not assignable to type 'boolean'.
+!!! error TS2322:     Type 'string | number' is not assignable to type 'boolean'.
+!!! error TS2322:       Type 'string' is not assignable to type 'boolean'.
         [""+"foo"]: "",
         [""+"bar"]: 0
     }

tests/baselines/reference/computedPropertyNamesContextualType8_ES6.types

@@ -12,7 +12,7 @@ interface I {
 var o: I = {
 >o : I
 >I : I
->{    [""+"foo"]: "",    [""+"bar"]: 0} : { [x: string]: "" | 0; }
+>{    [""+"foo"]: "",    [""+"bar"]: 0} : { [x: string]: string | number; }
 
     [""+"foo"]: "",
 >""+"foo" : string

tests/baselines/reference/computedPropertyNamesContextualType9_ES5.errors.txt

@@ -1,7 +1,7 @@
-tests/cases/conformance/es6/computedProperties/computedPropertyNamesContextualType9_ES5.ts(6,5): error TS2322: Type '{ [x: number]: "" | 0; }' is not assignable to type 'I'.
+tests/cases/conformance/es6/computedProperties/computedPropertyNamesContextualType9_ES5.ts(6,5): error TS2322: Type '{ [x: number]: string | number; }' is not assignable to type 'I'.
   Index signatures are incompatible.
-    Type '"" | 0' is not assignable to type 'boolean'.
-      Type '""' is not assignable to type 'boolean'.
+    Type 'string | number' is not assignable to type 'boolean'.
+      Type 'string' is not assignable to type 'boolean'.
 
 
 ==== tests/cases/conformance/es6/computedProperties/computedPropertyNamesContextualType9_ES5.ts (1 errors) ====
@@ -12,10 +12,10 @@ tests/cases/conformance/es6/computedProperties/computedPropertyNamesContextualTy
     
     var o: I = {
         ~
-!!! error TS2322: Type '{ [x: number]: "" | 0; }' is not assignable to type 'I'.
+!!! error TS2322: Type '{ [x: number]: string | number; }' is not assignable to type 'I'.
 !!! error TS2322:   Index signatures are incompatible.
-!!! error TS2322:     Type '"" | 0' is not assignable to type 'boolean'.
-!!! error TS2322:       Type '""' is not assignable to type 'boolean'.
+!!! error TS2322:     Type 'string | number' is not assignable to type 'boolean'.
+!!! error TS2322:       Type 'string' is not assignable to type 'boolean'.
         [+"foo"]: "",
         [+"bar"]: 0
     }

tests/baselines/reference/computedPropertyNamesContextualType9_ES5.types

@@ -12,7 +12,7 @@ interface I {
 var o: I = {
 >o : I
 >I : I
->{    [+"foo"]: "",    [+"bar"]: 0} : { [x: number]: "" | 0; }
+>{    [+"foo"]: "",    [+"bar"]: 0} : { [x: number]: string | number; }
 
     [+"foo"]: "",
 >+"foo" : number

tests/baselines/reference/computedPropertyNamesContextualType9_ES6.errors.txt

@@ -1,7 +1,7 @@
-tests/cases/conformance/es6/computedProperties/computedPropertyNamesContextualType9_ES6.ts(6,5): error TS2322: Type '{ [x: number]: "" | 0; }' is not assignable to type 'I'.
+tests/cases/conformance/es6/computedProperties/computedPropertyNamesContextualType9_ES6.ts(6,5): error TS2322: Type '{ [x: number]: string | number; }' is not assignable to type 'I'.
   Index signatures are incompatible.
-    Type '"" | 0' is not assignable to type 'boolean'.
-      Type '""' is not assignable to type 'boolean'.
+    Type 'string | number' is not assignable to type 'boolean'.
+      Type 'string' is not assignable to type 'boolean'.
 
 
 ==== tests/cases/conformance/es6/computedProperties/computedPropertyNamesContextualType9_ES6.ts (1 errors) ====
@@ -12,10 +12,10 @@ tests/cases/conformance/es6/computedProperties/computedPropertyNamesContextualTy
     
     var o: I = {
         ~
-!!! error TS2322: Type '{ [x: number]: "" | 0; }' is not assignable to type 'I'.
+!!! error TS2322: Type '{ [x: number]: string | number; }' is not assignable to type 'I'.
 !!! error TS2322:   Index signatures are incompatible.
-!!! error TS2322:     Type '"" | 0' is not assignable to type 'boolean'.
-!!! error TS2322:       Type '""' is not assignable to type 'boolean'.
+!!! error TS2322:     Type 'string | number' is not assignable to type 'boolean'.
+!!! error TS2322:       Type 'string' is not assignable to type 'boolean'.
         [+"foo"]: "",
         [+"bar"]: 0
     }

tests/baselines/reference/computedPropertyNamesContextualType9_ES6.types

@@ -12,7 +12,7 @@ interface I {
 var o: I = {
 >o : I
 >I : I
->{    [+"foo"]: "",    [+"bar"]: 0} : { [x: number]: "" | 0; }
+>{    [+"foo"]: "",    [+"bar"]: 0} : { [x: number]: string | number; }
 
     [+"foo"]: "",
 >+"foo" : number

tests/baselines/reference/constEnumPropertyAccess1.types

@@ -34,7 +34,7 @@ var o: {
 >idx : number
 
 } = {
->{        1: true    } : { 1: true; }
+>{        1: true    } : { 1: boolean; }
 
         1: true
 >true : true

tests/baselines/reference/contextualTypeWithTuple.types

@@ -15,7 +15,7 @@ var numStrTuple2: [number, string] = [5, "foo", true];
 
 var numStrBoolTuple: [number, string, boolean] = [5, "foo", true];
 >numStrBoolTuple : [number, string, boolean]
->[5, "foo", true] : [number, string, true]
+>[5, "foo", true] : [number, string, boolean]
 >5 : 5
 >"foo" : "foo"
 >true : true

tests/baselines/reference/declarationEmitDestructuringArrayPattern2.types

@@ -38,11 +38,11 @@ var [a2, [b2, { x12, y12: c2 }]=["abc", { x12: 10, y12: false }]] = [1, ["hello"
 >10 : 10
 >y12 : boolean
 >false : false
->[1, ["hello", { x12: 5, y12: true }]] : [number, [string, { x12: number; y12: true; }]]
+>[1, ["hello", { x12: 5, y12: true }]] : [number, [string, { x12: number; y12: boolean; }]]
 >1 : 1
->["hello", { x12: 5, y12: true }] : [string, { x12: number; y12: true; }]
+>["hello", { x12: 5, y12: true }] : [string, { x12: number; y12: boolean; }]
 >"hello" : "hello"
->{ x12: 5, y12: true } : { x12: number; y12: true; }
+>{ x12: 5, y12: true } : { x12: number; y12: boolean; }
 >x12 : number
 >5 : 5
 >y12 : boolean

tests/baselines/reference/declarationsAndAssignments.errors.txt

@@ -17,10 +17,10 @@ tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts(73,11):
 tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts(73,14): error TS2525: Initializer provides no value for this binding element and the binding element has no default value.
 tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts(74,11): error TS2459: Type 'undefined[]' has no property 'a' and no string index signature.
 tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts(74,14): error TS2459: Type 'undefined[]' has no property 'b' and no string index signature.
-tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts(106,5): error TS2345: Argument of type '[number, [string, { y: false; }]]' is not assignable to parameter of type '[number, [string, { x: any; y?: boolean; }]]'.
-  Type '[string, { y: false; }]' is not assignable to type '[string, { x: any; y?: boolean; }]'.
-    Type '{ y: false; }' is not assignable to type '{ x: any; y?: boolean; }'.
-      Property 'x' is missing in type '{ y: false; }'.
+tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts(106,5): error TS2345: Argument of type '[number, [string, { y: boolean; }]]' is not assignable to parameter of type '[number, [string, { x: any; y?: boolean; }]]'.
+  Type '[string, { y: boolean; }]' is not assignable to type '[string, { x: any; y?: boolean; }]'.
+    Type '{ y: boolean; }' is not assignable to type '{ x: any; y?: boolean; }'.
+      Property 'x' is missing in type '{ y: boolean; }'.
 tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts(138,6): error TS2322: Type 'string' is not assignable to type 'number'.
 tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts(138,9): error TS2322: Type 'number' is not assignable to type 'string'.
 
@@ -171,10 +171,10 @@ tests/cases/conformance/es6/destructuring/declarationsAndAssignments.ts(138,9):
     f14([2, ["abc", { x: 0 }]]);
     f14([2, ["abc", { y: false }]]);  // Error, no x
         ~~~~~~~~~~~~~~~~~~~~~~~~~~
-!!! error TS2345: Argument of type '[number, [string, { y: false; }]]' is not assignable to parameter of type '[number, [string, { x: any; y?: boolean; }]]'.
-!!! error TS2345:   Type '[string, { y: false; }]' is not assignable to type '[string, { x: any; y?: boolean; }]'.
-!!! error TS2345:     Type '{ y: false; }' is not assignable to type '{ x: any; y?: boolean; }'.
-!!! error TS2345:       Property 'x' is missing in type '{ y: false; }'.
+!!! error TS2345: Argument of type '[number, [string, { y: boolean; }]]' is not assignable to parameter of type '[number, [string, { x: any; y?: boolean; }]]'.
+!!! error TS2345:   Type '[string, { y: boolean; }]' is not assignable to type '[string, { x: any; y?: boolean; }]'.
+!!! error TS2345:     Type '{ y: boolean; }' is not assignable to type '{ x: any; y?: boolean; }'.
+!!! error TS2345:       Property 'x' is missing in type '{ y: boolean; }'.
     
     module M {
         export var [a, b] = [1, 2];

tests/baselines/reference/declarationsAndAssignments.types

@@ -363,11 +363,11 @@ function f12() {
 >10 : 10
 >y : boolean
 >false : false
->[1, ["hello", { x: 5, y: true }]] : [number, [string, { x: number; y: true; }]]
+>[1, ["hello", { x: 5, y: true }]] : [number, [string, { x: number; y: boolean; }]]
 >1 : 1
->["hello", { x: 5, y: true }] : [string, { x: number; y: true; }]
+>["hello", { x: 5, y: true }] : [string, { x: number; y: boolean; }]
 >"hello" : "hello"
->{ x: 5, y: true } : { x: number; y: true; }
+>{ x: 5, y: true } : { x: number; y: boolean; }
 >x : number
 >5 : 5
 >y : boolean
@@ -433,11 +433,11 @@ function f14([a = 1, [b = "hello", { x, y: c = false }]]) {
 f14([2, ["abc", { x: 0, y: true }]]);
 >f14([2, ["abc", { x: 0, y: true }]]) : void
 >f14 : ([a, [b, { x, y: c }]]: [number, [string, { x: any; y?: boolean; }]]) => void
->[2, ["abc", { x: 0, y: true }]] : [number, [string, { x: number; y: true; }]]
+>[2, ["abc", { x: 0, y: true }]] : [number, [string, { x: number; y: boolean; }]]
 >2 : 2
->["abc", { x: 0, y: true }] : [string, { x: number; y: true; }]
+>["abc", { x: 0, y: true }] : [string, { x: number; y: boolean; }]
 >"abc" : "abc"
->{ x: 0, y: true } : { x: number; y: true; }
+>{ x: 0, y: true } : { x: number; y: boolean; }
 >x : number
 >0 : 0
 >y : boolean
@@ -534,7 +534,7 @@ f17({ a: "hello" });
 f17({ c: true });
 >f17({ c: true }) : void
 >f17 : ({ a, b, c }: { a?: string; b?: number; c?: boolean; }) => void
->{ c: true } : { c: true; }
+>{ c: true } : { c: boolean; }
 >c : boolean
 >true : true
 
@@ -818,47 +818,47 @@ function f21() {
 >true : true
 
     [...a] = [1, "hello", true];
->[...a] = [1, "hello", true] : (true | 1 | "hello")[]
+>[...a] = [1, "hello", true] : (string | number | boolean)[]
 >[...a] : (string | number | boolean)[]
 >...a : string | number | boolean
 >a : (string | number | boolean)[]
->[1, "hello", true] : (true | 1 | "hello")[]
+>[1, "hello", true] : (string | number | boolean)[]
 >1 : 1
 >"hello" : "hello"
 >true : true
 
     [x, ...a] = [1, "hello", true];
->[x, ...a] = [1, "hello", true] : (true | 1 | "hello")[]
+>[x, ...a] = [1, "hello", true] : (string | number | boolean)[]
 >[x, ...a] : (string | number | boolean)[]
 >x : string | number | boolean
 >...a : string | number | boolean
 >a : (string | number | boolean)[]
->[1, "hello", true] : (true | 1 | "hello")[]
+>[1, "hello", true] : (string | number | boolean)[]
 >1 : 1
 >"hello" : "hello"
 >true : true
 
     [x, y, ...a] = [1, "hello", true];
->[x, y, ...a] = [1, "hello", true] : (true | 1 | "hello")[]
+>[x, y, ...a] = [1, "hello", true] : (string | number | boolean)[]
 >[x, y, ...a] : (string | number | boolean)[]
 >x : string | number | boolean
 >y : string | number | boolean
 >...a : string | number | boolean
 >a : (string | number | boolean)[]
->[1, "hello", true] : (true | 1 | "hello")[]
+>[1, "hello", true] : (string | number | boolean)[]
 >1 : 1
 >"hello" : "hello"
 >true : true
 
     [x, y, z, ...a] = [1, "hello", true];
->[x, y, z, ...a] = [1, "hello", true] : (true | 1 | "hello")[]
+>[x, y, z, ...a] = [1, "hello", true] : (string | number | boolean)[]
 >[x, y, z, ...a] : (string | number | boolean)[]
 >x : string | number | boolean
 >y : string | number | boolean
 >z : string | number | boolean
 >...a : string | number | boolean
 >a : (string | number | boolean)[]
->[1, "hello", true] : (true | 1 | "hello")[]
+>[1, "hello", true] : (string | number | boolean)[]
 >1 : 1
 >"hello" : "hello"
 >true : true

tests/baselines/reference/destructuringArrayBindingPatternAndAssignment1ES5.types

@@ -109,7 +109,7 @@ var [[[c3]], [[[[c4]]]]] = [[[]], [[[[]]]]]
 var [[c5], c6]: [[string|number], boolean] = [[1], true];
 >c5 : string | number
 >c6 : boolean
->[[1], true] : [[number], true]
+>[[1], true] : [[number], boolean]
 >[1] : [number]
 >1 : 1
 >true : true

tests/baselines/reference/destructuringArrayBindingPatternAndAssignment1ES5iterable.types

@@ -109,7 +109,7 @@ var [[[c3]], [[[[c4]]]]] = [[[]], [[[[]]]]]
 var [[c5], c6]: [[string|number], boolean] = [[1], true];
 >c5 : string | number
 >c6 : boolean
->[[1], true] : [[number], true]
+>[[1], true] : [[number], boolean]
 >[1] : [number]
 >1 : 1
 >true : true

tests/baselines/reference/destructuringArrayBindingPatternAndAssignment1ES6.types

@@ -109,7 +109,7 @@ var [[[c3]], [[[[c4]]]]] = [[[]], [[[[]]]]]
 var [[c5], c6]: [[string|number], boolean] = [[1], true];
 >c5 : string | number
 >c6 : boolean
->[[1], true] : [[number], true]
+>[[1], true] : [[number], boolean]
 >[1] : [number]
 >1 : 1
 >true : true

tests/baselines/reference/destructuringArrayBindingPatternAndAssignment2.errors.txt

@@ -1,8 +1,8 @@
 tests/cases/conformance/es6/destructuring/destructuringArrayBindingPatternAndAssignment2.ts(3,6): error TS2525: Initializer provides no value for this binding element and the binding element has no default value.
 tests/cases/conformance/es6/destructuring/destructuringArrayBindingPatternAndAssignment2.ts(3,12): error TS2525: Initializer provides no value for this binding element and the binding element has no default value.
 tests/cases/conformance/es6/destructuring/destructuringArrayBindingPatternAndAssignment2.ts(4,5): error TS2461: Type 'undefined' is not an array type.
-tests/cases/conformance/es6/destructuring/destructuringArrayBindingPatternAndAssignment2.ts(9,5): error TS2322: Type '[number, 2, string]' is not assignable to type '[number, boolean, string]'.
-  Type '2' is not assignable to type 'boolean'.
+tests/cases/conformance/es6/destructuring/destructuringArrayBindingPatternAndAssignment2.ts(9,5): error TS2322: Type '[number, number, string]' is not assignable to type '[number, boolean, string]'.
+  Type 'number' is not assignable to type 'boolean'.
 tests/cases/conformance/es6/destructuring/destructuringArrayBindingPatternAndAssignment2.ts(22,5): error TS2322: Type 'number[]' is not assignable to type '[number, number]'.
   Property '0' is missing in type 'number[]'.
 tests/cases/conformance/es6/destructuring/destructuringArrayBindingPatternAndAssignment2.ts(23,5): error TS2322: Type 'number[]' is not assignable to type '[string, string]'.
@@ -27,8 +27,8 @@ tests/cases/conformance/es6/destructuring/destructuringArrayBindingPatternAndAss
     //        where N is the numeric index of E in the array assignment pattern, or
     var [b0, b1, b2]: [number, boolean, string] = [1, 2, "string"];  // Error
         ~~~~~~~~~~~~
-!!! error TS2322: Type '[number, 2, string]' is not assignable to type '[number, boolean, string]'.
-!!! error TS2322:   Type '2' is not assignable to type 'boolean'.
+!!! error TS2322: Type '[number, number, string]' is not assignable to type '[number, boolean, string]'.
+!!! error TS2322:   Type 'number' is not assignable to type 'boolean'.
     interface J extends Array<Number> {
         2: number;
     }

tests/baselines/reference/destructuringArrayBindingPatternAndAssignment2.types

@@ -18,7 +18,7 @@ var [b0, b1, b2]: [number, boolean, string] = [1, 2, "string"];  // Error
 >b0 : number
 >b1 : boolean
 >b2 : string
->[1, 2, "string"] : [number, 2, string]
+>[1, 2, "string"] : [number, number, string]
 >1 : 1
 >2 : 2
 >"string" : "string"
@@ -86,7 +86,7 @@ function foo(idx: number): F {
 >F : F
 
     return {
->{        2: true    } : { 2: true; }
+>{        2: true    } : { 2: boolean; }
 
         2: true
 >true : true

tests/baselines/reference/destructuringObjectBindingPatternAndAssignment1ES5.types

@@ -69,7 +69,7 @@ function foo(): F {
 >F : F
 
     return {
->{        1: true    } : { 1: true; }
+>{        1: true    } : { 1: boolean; }
 
         1: true
 >true : true
@@ -82,7 +82,7 @@ function bar(): F {
 >F : F
 
     return {
->{        2: true    } : { 2: true; }
+>{        2: true    } : { 2: boolean; }
 
         2: true
 >true : true

tests/baselines/reference/destructuringObjectBindingPatternAndAssignment1ES6.types

@@ -69,7 +69,7 @@ function foo(): F {
 >F : F
 
     return {
->{        1: true    } : { 1: true; }
+>{        1: true    } : { 1: boolean; }
 
         1: true
 >true : true
@@ -82,7 +82,7 @@ function bar(): F {
 >F : F
 
     return {
->{        2: true    } : { 2: true; }
+>{        2: true    } : { 2: boolean; }
 
         2: true
 >true : true

tests/baselines/reference/destructuringParameterProperties1.types

@@ -104,7 +104,7 @@ var c3 = new C3({x: 0, y: "", z: false});
 >c3 : C3
 >new C3({x: 0, y: "", z: false}) : C3
 >C3 : typeof C3
->{x: 0, y: "", z: false} : { x: number; y: string; z: false; }
+>{x: 0, y: "", z: false} : { x: number; y: string; z: boolean; }
 >x : number
 >0 : 0
 >y : string
@@ -117,7 +117,7 @@ c3 = new C3({x: 0, "y": "y", z: true});
 >c3 : C3
 >new C3({x: 0, "y": "y", z: true}) : C3
 >C3 : typeof C3
->{x: 0, "y": "y", z: true} : { x: number; "y": string; z: true; }
+>{x: 0, "y": "y", z: true} : { x: number; "y": string; z: boolean; }
 >x : number
 >0 : 0
 >"y" : "y"

tests/baselines/reference/destructuringParameterProperties2.errors.txt

@@ -5,8 +5,8 @@ tests/cases/conformance/es6/destructuring/destructuringParameterProperties2.ts(4
 tests/cases/conformance/es6/destructuring/destructuringParameterProperties2.ts(9,21): error TS2339: Property 'a' does not exist on type 'C1'.
 tests/cases/conformance/es6/destructuring/destructuringParameterProperties2.ts(13,21): error TS2339: Property 'b' does not exist on type 'C1'.
 tests/cases/conformance/es6/destructuring/destructuringParameterProperties2.ts(17,21): error TS2339: Property 'c' does not exist on type 'C1'.
-tests/cases/conformance/es6/destructuring/destructuringParameterProperties2.ts(21,27): error TS2345: Argument of type '[number, undefined, ""]' is not assignable to parameter of type '[number, string, boolean]'.
-  Type '""' is not assignable to type 'boolean'.
+tests/cases/conformance/es6/destructuring/destructuringParameterProperties2.ts(21,27): error TS2345: Argument of type '[number, undefined, string]' is not assignable to parameter of type '[number, string, boolean]'.
+  Type 'string' is not assignable to type 'boolean'.
 
 
 ==== tests/cases/conformance/es6/destructuring/destructuringParameterProperties2.ts (8 errors) ====
@@ -46,8 +46,8 @@ tests/cases/conformance/es6/destructuring/destructuringParameterProperties2.ts(2
     
     var x = new C1(undefined, [0, undefined, ""]);
                               ~~~~~~~~~~~~~~~~~~
-!!! error TS2345: Argument of type '[number, undefined, ""]' is not assignable to parameter of type '[number, string, boolean]'.
-!!! error TS2345:   Type '""' is not assignable to type 'boolean'.
+!!! error TS2345: Argument of type '[number, undefined, string]' is not assignable to parameter of type '[number, string, boolean]'.
+!!! error TS2345:   Type 'string' is not assignable to type 'boolean'.
     var [x_a, x_b, x_c] = [x.getA(), x.getB(), x.getC()];
     
     var y = new C1(10, [0, "", true]);

tests/baselines/reference/destructuringParameterProperties2.types

@@ -103,7 +103,7 @@ var y = new C1(10, [0, "", true]);
 >new C1(10, [0, "", true]) : C1
 >C1 : typeof C1
 >10 : 10
->[0, "", true] : [number, string, true]
+>[0, "", true] : [number, string, boolean]
 >0 : 0
 >"" : ""
 >true : true

tests/baselines/reference/destructuringParameterProperties3.types

@@ -82,7 +82,7 @@ var x = new C1(undefined, [0, true, ""]);
 >new C1(undefined, [0, true, ""]) : C1<number, boolean, string>
 >C1 : typeof C1
 >undefined : undefined
->[0, true, ""] : [number, true, string]
+>[0, true, ""] : [number, boolean, string]
 >0 : 0
 >true : true
 >"" : ""
@@ -110,7 +110,7 @@ var y = new C1(10, [0, true, true]);
 >new C1(10, [0, true, true]) : C1<number, boolean, boolean>
 >C1 : typeof C1
 >10 : 10
->[0, true, true] : [number, true, true]
+>[0, true, true] : [number, boolean, boolean]
 >0 : 0
 >true : true
 >true : true

tests/baselines/reference/destructuringVariableDeclaration1ES5.types

@@ -16,7 +16,7 @@ var [a3, [[a4]], a5]: [number, [[string]], boolean] = [1, [["hello"]], true];
 >a3 : number
 >a4 : string
 >a5 : boolean
->[1, [["hello"]], true] : [number, [[string]], true]
+>[1, [["hello"]], true] : [number, [[string]], boolean]
 >1 : 1
 >[["hello"]] : [[string]]
 >["hello"] : [string]
@@ -52,10 +52,10 @@ var [b2 = 3, b3 = true, b4 = temp] = [3, false, { t1: false, t2: "hello" }];
 >true : true
 >b4 : { t1: boolean; t2: string; }
 >temp : { t1: boolean; t2: string; }
->[3, false, { t1: false, t2: "hello" }] : [number, false, { t1: false; t2: string; }]
+>[3, false, { t1: false, t2: "hello" }] : [number, boolean, { t1: boolean; t2: string; }]
 >3 : 3
 >false : false
->{ t1: false, t2: "hello" } : { t1: false; t2: string; }
+>{ t1: false, t2: "hello" } : { t1: boolean; t2: string; }
 >t1 : boolean
 >false : false
 >t2 : string

tests/baselines/reference/destructuringVariableDeclaration1ES5iterable.types

@@ -16,7 +16,7 @@ var [a3, [[a4]], a5]: [number, [[string]], boolean] = [1, [["hello"]], true];
 >a3 : number
 >a4 : string
 >a5 : boolean
->[1, [["hello"]], true] : [number, [[string]], true]
+>[1, [["hello"]], true] : [number, [[string]], boolean]
 >1 : 1
 >[["hello"]] : [[string]]
 >["hello"] : [string]
@@ -52,10 +52,10 @@ var [b2 = 3, b3 = true, b4 = temp] = [3, false, { t1: false, t2: "hello" }];
 >true : true
 >b4 : { t1: boolean; t2: string; }
 >temp : { t1: boolean; t2: string; }
->[3, false, { t1: false, t2: "hello" }] : [number, false, { t1: false; t2: string; }]
+>[3, false, { t1: false, t2: "hello" }] : [number, boolean, { t1: boolean; t2: string; }]
 >3 : 3
 >false : false
->{ t1: false, t2: "hello" } : { t1: false; t2: string; }
+>{ t1: false, t2: "hello" } : { t1: boolean; t2: string; }
 >t1 : boolean
 >false : false
 >t2 : string

tests/baselines/reference/destructuringVariableDeclaration1ES6.types

@@ -16,7 +16,7 @@ var [a3, [[a4]], a5]: [number, [[string]], boolean] = [1, [["hello"]], true];
 >a3 : number
 >a4 : string
 >a5 : boolean
->[1, [["hello"]], true] : [number, [[string]], true]
+>[1, [["hello"]], true] : [number, [[string]], boolean]
 >1 : 1
 >[["hello"]] : [[string]]
 >["hello"] : [string]
@@ -52,10 +52,10 @@ var [b2 = 3, b3 = true, b4 = temp] = [3, false, { t1: false, t2: "hello" }];
 >true : true
 >b4 : { t1: boolean; t2: string; }
 >temp : { t1: boolean; t2: string; }
->[3, false, { t1: false, t2: "hello" }] : [number, false, { t1: false; t2: string; }]
+>[3, false, { t1: false, t2: "hello" }] : [number, boolean, { t1: boolean; t2: string; }]
 >3 : 3
 >false : false
->{ t1: false, t2: "hello" } : { t1: false; t2: string; }
+>{ t1: false, t2: "hello" } : { t1: boolean; t2: string; }
 >t1 : boolean
 >false : false
 >t2 : string

tests/baselines/reference/destructuringVariableDeclaration2.errors.txt

@@ -1,7 +1,7 @@
 tests/cases/conformance/es6/destructuring/destructuringVariableDeclaration2.ts(3,5): error TS2322: Type '{ a1: boolean; a2: number; }' is not assignable to type '{ a1: number; a2: string; }'.
   Types of property 'a1' are incompatible.
     Type 'boolean' is not assignable to type 'number'.
-tests/cases/conformance/es6/destructuring/destructuringVariableDeclaration2.ts(4,5): error TS2322: Type '[number, [[boolean]], true]' is not assignable to type '[number, [[string]], boolean]'.
+tests/cases/conformance/es6/destructuring/destructuringVariableDeclaration2.ts(4,5): error TS2322: Type '[number, [[boolean]], boolean]' is not assignable to type '[number, [[string]], boolean]'.
   Type '[[boolean]]' is not assignable to type '[[string]]'.
     Type '[boolean]' is not assignable to type '[string]'.
       Type 'boolean' is not assignable to type 'string'.
@@ -19,7 +19,7 @@ tests/cases/conformance/es6/destructuring/destructuringVariableDeclaration2.ts(1
 !!! error TS2322:     Type 'boolean' is not assignable to type 'number'.
     var [a3, [[a4]], a5]: [number, [[string]], boolean] = [1, [[false]], true];  // Error
         ~~~~~~~~~~~~~~~~
-!!! error TS2322: Type '[number, [[boolean]], true]' is not assignable to type '[number, [[string]], boolean]'.
+!!! error TS2322: Type '[number, [[boolean]], boolean]' is not assignable to type '[number, [[string]], boolean]'.
 !!! error TS2322:   Type '[[boolean]]' is not assignable to type '[[string]]'.
 !!! error TS2322:     Type '[boolean]' is not assignable to type '[string]'.
 !!! error TS2322:       Type 'boolean' is not assignable to type 'string'.

tests/baselines/reference/destructuringVariableDeclaration2.types

@@ -16,7 +16,7 @@ var [a3, [[a4]], a5]: [number, [[string]], boolean] = [1, [[false]], true];  //
 >a3 : number
 >a4 : string
 >a5 : boolean
->[1, [[false]], true] : [number, [[boolean]], true]
+>[1, [[false]], true] : [number, [[boolean]], boolean]
 >1 : 1
 >[[false]] : [[boolean]]
 >[false] : [boolean]
@@ -38,12 +38,12 @@ var [b0 = 3, b1 = true, b2 = temp] = [3, false, { t1: false, t2: 5}];  // Error
 >3 : 3
 >b1 : boolean
 >true : true
->b2 : { t1: boolean; t2: string; } | { t1: false; t2: number; }
+>b2 : { t1: boolean; t2: string; } | { t1: boolean; t2: number; }
 >temp : { t1: boolean; t2: string; }
->[3, false, { t1: false, t2: 5}] : [number, false, { t1: false; t2: number; }]
+>[3, false, { t1: false, t2: 5}] : [number, boolean, { t1: boolean; t2: number; }]
 >3 : 3
 >false : false
->{ t1: false, t2: 5} : { t1: false; t2: number; }
+>{ t1: false, t2: 5} : { t1: boolean; t2: number; }
 >t1 : boolean
 >false : false
 >t2 : number

tests/baselines/reference/disallowLineTerminatorBeforeArrow.types

@@ -150,7 +150,7 @@ function foo(func: () => boolean) { }
 foo(()
 >foo(()    => true) : void
 >foo : (func: () => boolean) => void
->()    => true : () => true
+>()    => true : () => boolean
 
     => true);
 >true : true
@@ -158,7 +158,7 @@ foo(()
 foo(()
 >foo(()    => { return false; }) : void
 >foo : (func: () => boolean) => void
->()    => { return false; } : () => false
+>()    => { return false; } : () => boolean
 
     => { return false; });
 >false : false

tests/baselines/reference/duplicateLocalVariable1.types

@@ -230,7 +230,7 @@ export var tests: TestRunner = (function () {
 >new TestCase("Basic test", function () { return true; }) : TestCase
 >TestCase : typeof TestCase
 >"Basic test" : "Basic test"
->function () { return true; } : () => true
+>function () { return true; } : () => boolean
 >true : true
 
     testRunner.addTest(new TestCase("Test for any error", function () { throw new Error(); return false; }, ""));
@@ -241,7 +241,7 @@ export var tests: TestRunner = (function () {
 >new TestCase("Test for any error", function () { throw new Error(); return false; }, "") : TestCase
 >TestCase : typeof TestCase
 >"Test for any error" : "Test for any error"
->function () { throw new Error(); return false; } : () => false
+>function () { throw new Error(); return false; } : () => boolean
 >new Error() : Error
 >Error : ErrorConstructor
 >false : false
@@ -255,7 +255,7 @@ export var tests: TestRunner = (function () {
 >new TestCase("Test RegEx error message match", function () { throw new Error("Should also pass"); return false; }, "Should [also]+ pass") : TestCase
 >TestCase : typeof TestCase
 >"Test RegEx error message match" : "Test RegEx error message match"
->function () { throw new Error("Should also pass"); return false; } : () => false
+>function () { throw new Error("Should also pass"); return false; } : () => boolean
 >new Error("Should also pass") : Error
 >Error : ErrorConstructor
 >"Should also pass" : "Should also pass"
@@ -1104,7 +1104,7 @@ export var tests: TestRunner = (function () {
 >"Check saving a file" : "Check saving a file"
 
         function () {
->function () {            var filename = TestFileDir + "\\tmpUTF16LE.txt";            var fb = new FileManager.FileBuffer(14);            fb.writeUtf16leBom();            var chars = [0x0054, 0x00E8, 0x1D23, 0x2020, 0x000D, 0x000A];            chars.forEach(function (val) { fb.writeUtf16CodePoint(val, false); });            fb.save(filename);            var savedFile = new FileManager.FileBuffer(filename);            if (savedFile.encoding !== 'utf16le') {                throw Error("Incorrect encoding");            }            var expectedBytes = [0xFF, 0xFE, 0x54, 0x00, 0xE8, 0x00, 0x23, 0x1D, 0x20, 0x20, 0x0D, 0x00, 0x0A, 0x00]            savedFile.index = 0;            expectedBytes.forEach(function (val) {                var byteVal = savedFile.readByte();                if (byteVal !== val) {                    throw Error("Incorrect byte value");                }            });            return true;        } : () => true
+>function () {            var filename = TestFileDir + "\\tmpUTF16LE.txt";            var fb = new FileManager.FileBuffer(14);            fb.writeUtf16leBom();            var chars = [0x0054, 0x00E8, 0x1D23, 0x2020, 0x000D, 0x000A];            chars.forEach(function (val) { fb.writeUtf16CodePoint(val, false); });            fb.save(filename);            var savedFile = new FileManager.FileBuffer(filename);            if (savedFile.encoding !== 'utf16le') {                throw Error("Incorrect encoding");            }            var expectedBytes = [0xFF, 0xFE, 0x54, 0x00, 0xE8, 0x00, 0x23, 0x1D, 0x20, 0x20, 0x0D, 0x00, 0x0A, 0x00]            savedFile.index = 0;            expectedBytes.forEach(function (val) {                var byteVal = savedFile.readByte();                if (byteVal !== val) {                    throw Error("Incorrect byte value");                }            });            return true;        } : () => boolean
 
             var filename = TestFileDir + "\\tmpUTF16LE.txt";
 >filename : string
@@ -1243,7 +1243,7 @@ export var tests: TestRunner = (function () {
 >"Check reading past buffer asserts" : "Check reading past buffer asserts"
 
     function () {
->function () {        var fb = new FileManager.FileBuffer(TestFileDir + "\\UTF8BOM.txt");        var result = fb.readByte(200);        return true;    } : () => true
+>function () {        var fb = new FileManager.FileBuffer(TestFileDir + "\\UTF8BOM.txt");        var result = fb.readByte(200);        return true;    } : () => boolean
 
         var fb = new FileManager.FileBuffer(TestFileDir + "\\UTF8BOM.txt");
 >fb : any
@@ -1279,7 +1279,7 @@ export var tests: TestRunner = (function () {
 >"Check writing past buffer asserts" : "Check writing past buffer asserts"
 
     function () {
->function () {        var fb = new FileManager.FileBuffer(TestFileDir + "\\UTF8BOM.txt");        fb.writeByte(5, 200);        return true;    } : () => true
+>function () {        var fb = new FileManager.FileBuffer(TestFileDir + "\\UTF8BOM.txt");        fb.writeByte(5, 200);        return true;    } : () => boolean
 
         var fb = new FileManager.FileBuffer(TestFileDir + "\\UTF8BOM.txt");
 >fb : any
@@ -1473,7 +1473,7 @@ export var tests: TestRunner = (function () {
 >"Write non-BMP utf8 chars" : "Write non-BMP utf8 chars"
 
         function () {
->function () {            var filename = TestFileDir + "\\tmpUTF8nonBmp.txt";            var fb = new FileManager.FileBuffer(15);            var chars = [0x10480, 0x10481, 0x10482, 0x54, 0x68, 0x69];            chars.forEach(function (val) { fb.writeUtf8CodePoint(val); });            fb.save(filename);            var savedFile = new FileManager.FileBuffer(filename);            if (savedFile.encoding !== 'utf8') {                throw Error("Incorrect encoding");            }            var expectedBytes = [0xF0, 0x90, 0x92, 0x80, 0xF0, 0x90, 0x92, 0x81, 0xF0, 0x90, 0x92, 0x82, 0x54, 0x68, 0x69];            expectedBytes.forEach(function (val) {                var byteVal = savedFile.readByte();                if (byteVal !== val) {                    throw Error("Incorrect byte value");                }            });            return true;        } : () => true
+>function () {            var filename = TestFileDir + "\\tmpUTF8nonBmp.txt";            var fb = new FileManager.FileBuffer(15);            var chars = [0x10480, 0x10481, 0x10482, 0x54, 0x68, 0x69];            chars.forEach(function (val) { fb.writeUtf8CodePoint(val); });            fb.save(filename);            var savedFile = new FileManager.FileBuffer(filename);            if (savedFile.encoding !== 'utf8') {                throw Error("Incorrect encoding");            }            var expectedBytes = [0xF0, 0x90, 0x92, 0x80, 0xF0, 0x90, 0x92, 0x81, 0xF0, 0x90, 0x92, 0x82, 0x54, 0x68, 0x69];            expectedBytes.forEach(function (val) {                var byteVal = savedFile.readByte();                if (byteVal !== val) {                    throw Error("Incorrect byte value");                }            });            return true;        } : () => boolean
 
             var filename = TestFileDir + "\\tmpUTF8nonBmp.txt";
 >filename : string
@@ -1599,7 +1599,7 @@ export var tests: TestRunner = (function () {
 >"Test invalid lead UTF8 byte" : "Test invalid lead UTF8 byte"
 
         function () {
->function () {            var filename = TestFileDir + "\\utf8BadLeadByte.txt";            var fb = new FileManager.FileBuffer(filename);            return true;        } : () => true
+>function () {            var filename = TestFileDir + "\\utf8BadLeadByte.txt";            var fb = new FileManager.FileBuffer(filename);            return true;        } : () => boolean
 
             var filename = TestFileDir + "\\utf8BadLeadByte.txt";
 >filename : string
@@ -1631,7 +1631,7 @@ export var tests: TestRunner = (function () {
 >"Test invalid tail UTF8 byte" : "Test invalid tail UTF8 byte"
 
         function () {
->function () {            var filename = TestFileDir + "\\utf8InvalidTail.txt";            var fb = new FileManager.FileBuffer(filename);            return true;        } : () => true
+>function () {            var filename = TestFileDir + "\\utf8InvalidTail.txt";            var fb = new FileManager.FileBuffer(filename);            return true;        } : () => boolean
 
             var filename = TestFileDir + "\\utf8InvalidTail.txt";
 >filename : string
@@ -1663,7 +1663,7 @@ export var tests: TestRunner = (function () {
 >"Test ANSI fails validation" : "Test ANSI fails validation"
 
         function () {
->function () {            var filename = TestFileDir + "\\ansi.txt";            var fb = new FileManager.FileBuffer(filename);            return true;        } : () => true
+>function () {            var filename = TestFileDir + "\\ansi.txt";            var fb = new FileManager.FileBuffer(filename);            return true;        } : () => boolean
 
             var filename = TestFileDir + "\\ansi.txt";
 >filename : string
@@ -1695,7 +1695,7 @@ export var tests: TestRunner = (function () {
 >"Test UTF-16LE with invalid surrogate trail fails" : "Test UTF-16LE with invalid surrogate trail fails"
 
         function () {
->function () {            var filename = TestFileDir + "\\utf16leInvalidSurrogate.txt";            var fb = new FileManager.FileBuffer(filename);            return true;        } : () => true
+>function () {            var filename = TestFileDir + "\\utf16leInvalidSurrogate.txt";            var fb = new FileManager.FileBuffer(filename);            return true;        } : () => boolean
 
             var filename = TestFileDir + "\\utf16leInvalidSurrogate.txt";
 >filename : string
@@ -1727,7 +1727,7 @@ export var tests: TestRunner = (function () {
 >"Test UTF-16BE with invalid surrogate head fails" : "Test UTF-16BE with invalid surrogate head fails"
 
         function () {
->function () {            var filename = TestFileDir + "\\UTF16BEInvalidSurrogate.txt";            var fb = new FileManager.FileBuffer(filename);            return true;        } : () => true
+>function () {            var filename = TestFileDir + "\\UTF16BEInvalidSurrogate.txt";            var fb = new FileManager.FileBuffer(filename);            return true;        } : () => boolean
 
             var filename = TestFileDir + "\\UTF16BEInvalidSurrogate.txt";
 >filename : string
@@ -1759,7 +1759,7 @@ export var tests: TestRunner = (function () {
 >"Test UTF-16LE with missing trail surrogate fails" : "Test UTF-16LE with missing trail surrogate fails"
 
         function () {
->function () {            var filename = TestFileDir + "\\utf16leMissingTrailSurrogate.txt";            var fb = new FileManager.FileBuffer(filename);            return true;        } : () => true
+>function () {            var filename = TestFileDir + "\\utf16leMissingTrailSurrogate.txt";            var fb = new FileManager.FileBuffer(filename);            return true;        } : () => boolean
 
             var filename = TestFileDir + "\\utf16leMissingTrailSurrogate.txt";
 >filename : string
@@ -1851,7 +1851,7 @@ export var tests: TestRunner = (function () {
 >"Test file with control character" : "Test file with control character"
 
         function () {
->function () {            var filename = TestFileDir + "\\controlChar.txt";            var fb = new FileManager.FileBuffer(filename);            return true;        } : () => true
+>function () {            var filename = TestFileDir + "\\controlChar.txt";            var fb = new FileManager.FileBuffer(filename);            return true;        } : () => boolean
 
             var filename = TestFileDir + "\\controlChar.txt";
 >filename : string

tests/baselines/reference/emitArrowFunction.types

@@ -31,12 +31,12 @@ function foo(func: () => boolean) { }
 foo(() => true);
 >foo(() => true) : void
 >foo : (func: () => boolean) => void
->() => true : () => true
+>() => true : () => boolean
 >true : true
 
 foo(() => { return false; });
 >foo(() => { return false; }) : void
 >foo : (func: () => boolean) => void
->() => { return false; } : () => false
+>() => { return false; } : () => boolean
 >false : false
 

tests/baselines/reference/emitArrowFunctionES6.types

@@ -31,13 +31,13 @@ function foo(func: () => boolean) { }
 foo(() => true);
 >foo(() => true) : void
 >foo : (func: () => boolean) => void
->() => true : () => true
+>() => true : () => boolean
 >true : true
 
 foo(() => { return false; });
 >foo(() => { return false; }) : void
 >foo : (func: () => boolean) => void
->() => { return false; } : () => false
+>() => { return false; } : () => boolean
 >false : false
 
 // Binding patterns in arrow functions

tests/baselines/reference/emitArrowFunctionThisCapturing.types

@@ -32,7 +32,7 @@ function foo(func: () => boolean) { }
 foo(() => {
 >foo(() => {    this.age = 100;    return true;}) : void
 >foo : (func: () => boolean) => void
->() => {    this.age = 100;    return true;} : () => true
+>() => {    this.age = 100;    return true;} : () => boolean
 
     this.age = 100;
 >this.age = 100 : 100

tests/baselines/reference/emitArrowFunctionThisCapturingES6.types

@@ -32,7 +32,7 @@ function foo(func: () => boolean){ }
 foo(() => {
 >foo(() => {    this.age = 100;    return true;}) : void
 >foo : (func: () => boolean) => void
->() => {    this.age = 100;    return true;} : () => true
+>() => {    this.age = 100;    return true;} : () => boolean
 
     this.age = 100;
 >this.age = 100 : 100

tests/baselines/reference/excessPropertyCheckWithUnions.errors.txt

@@ -13,8 +13,8 @@ tests/cases/compiler/excessPropertyCheckWithUnions.ts(39,1): error TS2322: Type
   Type '{ tag: "A"; }' is not assignable to type '{ tag: "C"; }'.
     Types of property 'tag' are incompatible.
       Type '"A"' is not assignable to type '"C"'.
-tests/cases/compiler/excessPropertyCheckWithUnions.ts(40,1): error TS2322: Type '{ tag: "A"; z: true; }' is not assignable to type 'Ambiguous'.
-  Type '{ tag: "A"; z: true; }' is not assignable to type '{ tag: "C"; }'.
+tests/cases/compiler/excessPropertyCheckWithUnions.ts(40,1): error TS2322: Type '{ tag: "A"; z: boolean; }' is not assignable to type 'Ambiguous'.
+  Type '{ tag: "A"; z: boolean; }' is not assignable to type '{ tag: "C"; }'.
     Types of property 'tag' are incompatible.
       Type '"A"' is not assignable to type '"C"'.
 tests/cases/compiler/excessPropertyCheckWithUnions.ts(49,35): error TS2322: Type '{ a: 1; b: 1; first: string; second: string; }' is not assignable to type 'Overlapping'.
@@ -86,8 +86,8 @@ tests/cases/compiler/excessPropertyCheckWithUnions.ts(50,35): error TS2322: Type
 !!! error TS2322:       Type '"A"' is not assignable to type '"C"'.
     amb = { tag: "A", z: true }
     ~~~
-!!! error TS2322: Type '{ tag: "A"; z: true; }' is not assignable to type 'Ambiguous'.
-!!! error TS2322:   Type '{ tag: "A"; z: true; }' is not assignable to type '{ tag: "C"; }'.
+!!! error TS2322: Type '{ tag: "A"; z: boolean; }' is not assignable to type 'Ambiguous'.
+!!! error TS2322:   Type '{ tag: "A"; z: boolean; }' is not assignable to type '{ tag: "C"; }'.
 !!! error TS2322:     Types of property 'tag' are incompatible.
 !!! error TS2322:       Type '"A"' is not assignable to type '"C"'.
     

tests/baselines/reference/excessPropertyCheckWithUnions.types

@@ -139,9 +139,9 @@ amb = { tag: "A" }
 >"A" : "A"
 
 amb = { tag: "A", z: true }
->amb = { tag: "A", z: true } : { tag: "A"; z: true; }
+>amb = { tag: "A", z: true } : { tag: "A"; z: boolean; }
 >amb : Ambiguous
->{ tag: "A", z: true } : { tag: "A"; z: true; }
+>{ tag: "A", z: true } : { tag: "A"; z: boolean; }
 >tag : string
 >"A" : "A"
 >z : boolean

tests/baselines/reference/for-of36.types

@@ -1,7 +1,7 @@
 === tests/cases/conformance/es6/for-ofStatements/for-of36.ts ===
 var tuple: [string, boolean] = ["", true];
 >tuple : [string, boolean]
->["", true] : [string, true]
+>["", true] : [string, boolean]
 >"" : ""
 >true : true
 

tests/baselines/reference/for-of37.types

@@ -3,8 +3,8 @@ var map = new Map([["", true]]);
 >map : Map<string, boolean>
 >new Map([["", true]]) : Map<string, boolean>
 >Map : MapConstructor
->[["", true]] : [string, true][]
->["", true] : [string, true]
+>[["", true]] : [string, boolean][]
+>["", true] : [string, boolean]
 >"" : ""
 >true : true
 

tests/baselines/reference/for-of38.types

@@ -3,8 +3,8 @@ var map = new Map([["", true]]);
 >map : Map<string, boolean>
 >new Map([["", true]]) : Map<string, boolean>
 >Map : MapConstructor
->[["", true]] : [string, true][]
->["", true] : [string, true]
+>[["", true]] : [string, boolean][]
+>["", true] : [string, boolean]
 >"" : ""
 >true : true
 

tests/baselines/reference/for-of39.errors.txt

@@ -1,28 +1,28 @@
-tests/cases/conformance/es6/for-ofStatements/for-of39.ts(1,19): error TS2345: Argument of type '([string, true] | [string, 0])[]' is not assignable to parameter of type 'Iterable<[string, boolean]>'.
+tests/cases/conformance/es6/for-ofStatements/for-of39.ts(1,19): error TS2345: Argument of type '([string, boolean] | [string, number])[]' is not assignable to parameter of type 'Iterable<[string, boolean]>'.
   Types of property '[Symbol.iterator]' are incompatible.
-    Type '() => IterableIterator<[string, true] | [string, 0]>' is not assignable to type '() => Iterator<[string, boolean]>'.
-      Type 'IterableIterator<[string, true] | [string, 0]>' is not assignable to type 'Iterator<[string, boolean]>'.
+    Type '() => IterableIterator<[string, boolean] | [string, number]>' is not assignable to type '() => Iterator<[string, boolean]>'.
+      Type 'IterableIterator<[string, boolean] | [string, number]>' is not assignable to type 'Iterator<[string, boolean]>'.
         Types of property 'next' are incompatible.
-          Type '(value?: any) => IteratorResult<[string, true] | [string, 0]>' is not assignable to type '(value?: any) => IteratorResult<[string, boolean]>'.
-            Type 'IteratorResult<[string, true] | [string, 0]>' is not assignable to type 'IteratorResult<[string, boolean]>'.
-              Type '[string, true] | [string, 0]' is not assignable to type '[string, boolean]'.
-                Type '[string, 0]' is not assignable to type '[string, boolean]'.
-                  Type '0' is not assignable to type 'boolean'.
+          Type '(value?: any) => IteratorResult<[string, boolean] | [string, number]>' is not assignable to type '(value?: any) => IteratorResult<[string, boolean]>'.
+            Type 'IteratorResult<[string, boolean] | [string, number]>' is not assignable to type 'IteratorResult<[string, boolean]>'.
+              Type '[string, boolean] | [string, number]' is not assignable to type '[string, boolean]'.
+                Type '[string, number]' is not assignable to type '[string, boolean]'.
+                  Type 'number' is not assignable to type 'boolean'.
 
 
 ==== tests/cases/conformance/es6/for-ofStatements/for-of39.ts (1 errors) ====
     var map = new Map([["", true], ["", 0]]);
                       ~~~~~~~~~~~~~~~~~~~~~
-!!! error TS2345: Argument of type '([string, true] | [string, 0])[]' is not assignable to parameter of type 'Iterable<[string, boolean]>'.
+!!! error TS2345: Argument of type '([string, boolean] | [string, number])[]' is not assignable to parameter of type 'Iterable<[string, boolean]>'.
 !!! error TS2345:   Types of property '[Symbol.iterator]' are incompatible.
-!!! error TS2345:     Type '() => IterableIterator<[string, true] | [string, 0]>' is not assignable to type '() => Iterator<[string, boolean]>'.
-!!! error TS2345:       Type 'IterableIterator<[string, true] | [string, 0]>' is not assignable to type 'Iterator<[string, boolean]>'.
+!!! error TS2345:     Type '() => IterableIterator<[string, boolean] | [string, number]>' is not assignable to type '() => Iterator<[string, boolean]>'.
+!!! error TS2345:       Type 'IterableIterator<[string, boolean] | [string, number]>' is not assignable to type 'Iterator<[string, boolean]>'.
 !!! error TS2345:         Types of property 'next' are incompatible.
-!!! error TS2345:           Type '(value?: any) => IteratorResult<[string, true] | [string, 0]>' is not assignable to type '(value?: any) => IteratorResult<[string, boolean]>'.
-!!! error TS2345:             Type 'IteratorResult<[string, true] | [string, 0]>' is not assignable to type 'IteratorResult<[string, boolean]>'.
-!!! error TS2345:               Type '[string, true] | [string, 0]' is not assignable to type '[string, boolean]'.
-!!! error TS2345:                 Type '[string, 0]' is not assignable to type '[string, boolean]'.
-!!! error TS2345:                   Type '0' is not assignable to type 'boolean'.
+!!! error TS2345:           Type '(value?: any) => IteratorResult<[string, boolean] | [string, number]>' is not assignable to type '(value?: any) => IteratorResult<[string, boolean]>'.
+!!! error TS2345:             Type 'IteratorResult<[string, boolean] | [string, number]>' is not assignable to type 'IteratorResult<[string, boolean]>'.
+!!! error TS2345:               Type '[string, boolean] | [string, number]' is not assignable to type '[string, boolean]'.
+!!! error TS2345:                 Type '[string, number]' is not assignable to type '[string, boolean]'.
+!!! error TS2345:                   Type 'number' is not assignable to type 'boolean'.
     for (var [k, v] of map) {
         k;
         v;

tests/baselines/reference/for-of40.types

@@ -3,8 +3,8 @@ var map = new Map([["", true]]);
 >map : Map<string, boolean>
 >new Map([["", true]]) : Map<string, boolean>
 >Map : MapConstructor
->[["", true]] : [string, true][]
->["", true] : [string, true]
+>[["", true]] : [string, boolean][]
+>["", true] : [string, boolean]
 >"" : ""
 >true : true
 

tests/baselines/reference/for-of44.types

@@ -1,11 +1,11 @@
 === tests/cases/conformance/es6/for-ofStatements/for-of44.ts ===
 var array: [number, string | boolean | symbol][] = [[0, ""], [0, true], [1, Symbol()]]
 >array : [number, string | boolean | symbol][]
->[[0, ""], [0, true], [1, Symbol()]] : ([number, ""] | [number, true] | [number, symbol])[]
->[0, ""] : [number, ""]
+>[[0, ""], [0, true], [1, Symbol()]] : ([number, string] | [number, boolean] | [number, symbol])[]
+>[0, ""] : [number, string]
 >0 : 0
 >"" : ""
->[0, true] : [number, true]
+>[0, true] : [number, boolean]
 >0 : 0
 >true : true
 >[1, Symbol()] : [number, symbol]

tests/baselines/reference/for-of45.types

@@ -7,8 +7,8 @@ var map = new Map([["", true]]);
 >map : Map<string, boolean>
 >new Map([["", true]]) : Map<string, boolean>
 >Map : MapConstructor
->[["", true]] : [string, true][]
->["", true] : [string, true]
+>[["", true]] : [string, boolean][]
+>["", true] : [string, boolean]
 >"" : ""
 >true : true
 

tests/baselines/reference/for-of46.types

@@ -7,8 +7,8 @@ var map = new Map([["", true]]);
 >map : Map<string, boolean>
 >new Map([["", true]]) : Map<string, boolean>
 >Map : MapConstructor
->[["", true]] : [string, true][]
->["", true] : [string, true]
+>[["", true]] : [string, boolean][]
+>["", true] : [string, boolean]
 >"" : ""
 >true : true
 

tests/baselines/reference/for-of49.types

@@ -7,8 +7,8 @@ var map = new Map([["", true]]);
 >map : Map<string, boolean>
 >new Map([["", true]]) : Map<string, boolean>
 >Map : MapConstructor
->[["", true]] : [string, true][]
->["", true] : [string, true]
+>[["", true]] : [string, boolean][]
+>["", true] : [string, boolean]
 >"" : ""
 >true : true
 

tests/baselines/reference/for-of50.types

@@ -3,8 +3,8 @@ var map = new Map([["", true]]);
 >map : Map<string, boolean>
 >new Map([["", true]]) : Map<string, boolean>
 >Map : MapConstructor
->[["", true]] : [string, true][]
->["", true] : [string, true]
+>[["", true]] : [string, boolean][]
+>["", true] : [string, boolean]
 >"" : ""
 >true : true
 

tests/baselines/reference/functionOverloads39.types

@@ -19,8 +19,8 @@ var x = foo([{a:true}]);
 >x : number
 >foo([{a:true}]) : number
 >foo : { (bar: { a: number; }[]): string; (bar: { a: boolean; }[]): number; }
->[{a:true}] : { a: true; }[]
->{a:true} : { a: true; }
+>[{a:true}] : { a: boolean; }[]
+>{a:true} : { a: boolean; }
 >a : boolean
 >true : true
 

tests/baselines/reference/functionOverloads40.errors.txt

@@ -1,7 +1,7 @@
-tests/cases/compiler/functionOverloads40.ts(4,13): error TS2345: Argument of type '{ a: "bar"; }[]' is not assignable to parameter of type '{ a: boolean; }[]'.
-  Type '{ a: "bar"; }' is not assignable to type '{ a: boolean; }'.
+tests/cases/compiler/functionOverloads40.ts(4,13): error TS2345: Argument of type '{ a: string; }[]' is not assignable to parameter of type '{ a: boolean; }[]'.
+  Type '{ a: string; }' is not assignable to type '{ a: boolean; }'.
     Types of property 'a' are incompatible.
-      Type '"bar"' is not assignable to type 'boolean'.
+      Type 'string' is not assignable to type 'boolean'.
 
 
 ==== tests/cases/compiler/functionOverloads40.ts (1 errors) ====
@@ -10,8 +10,8 @@ tests/cases/compiler/functionOverloads40.ts(4,13): error TS2345: Argument of typ
     function foo(bar:{a:any;}[]):any{ return bar }
     var x = foo([{a:'bar'}]);
                 ~~~~~~~~~~~
-!!! error TS2345: Argument of type '{ a: "bar"; }[]' is not assignable to parameter of type '{ a: boolean; }[]'.
-!!! error TS2345:   Type '{ a: "bar"; }' is not assignable to type '{ a: boolean; }'.
+!!! error TS2345: Argument of type '{ a: string; }[]' is not assignable to parameter of type '{ a: boolean; }[]'.
+!!! error TS2345:   Type '{ a: string; }' is not assignable to type '{ a: boolean; }'.
 !!! error TS2345:     Types of property 'a' are incompatible.
-!!! error TS2345:       Type '"bar"' is not assignable to type 'boolean'.
+!!! error TS2345:       Type 'string' is not assignable to type 'boolean'.
     

tests/baselines/reference/genericArgumentCallSigAssignmentCompat.types

@@ -64,7 +64,7 @@ _.all([true], _.identity);
 >_.all : <T>(list: T[], iterator?: Underscore.Iterator<T, boolean>, context?: any) => boolean
 >_ : Underscore.Static
 >all : <T>(list: T[], iterator?: Underscore.Iterator<T, boolean>, context?: any) => boolean
->[true] : true[]
+>[true] : boolean[]
 >true : true
 >_.identity : <T>(value: T) => T
 >_ : Underscore.Static

tests/baselines/reference/genericTypeArgumentInference1.types

@@ -62,7 +62,7 @@ var r2 = _.all([true], _.identity);
 >_.all : <T>(list: T[], iterator?: Underscore.Iterator<T, boolean>, context?: any) => T
 >_ : Underscore.Static
 >all : <T>(list: T[], iterator?: Underscore.Iterator<T, boolean>, context?: any) => T
->[true] : true[]
+>[true] : boolean[]
 >true : true
 >_.identity : <T>(value: T) => T
 >_ : Underscore.Static

tests/baselines/reference/getAndSetAsMemberNames.types

@@ -40,7 +40,7 @@ class C5 {
 
     public set: () => boolean = function () { return true; };
 >set : () => boolean
->function () { return true; } : () => true
+>function () { return true; } : () => boolean
 >true : true
 
     get (): boolean { return true; }

tests/baselines/reference/getterSetterNonAccessor.types

@@ -16,8 +16,8 @@ Object.defineProperty({}, "0", <PropertyDescriptor>({
 >"0" : "0"
 ><PropertyDescriptor>({          get: getFunc,          set: setFunc,          configurable: true      }) : PropertyDescriptor
 >PropertyDescriptor : PropertyDescriptor
->({          get: getFunc,          set: setFunc,          configurable: true      }) : { get: () => any; set: (v: any) => void; configurable: true; }
->{          get: getFunc,          set: setFunc,          configurable: true      } : { get: () => any; set: (v: any) => void; configurable: true; }
+>({          get: getFunc,          set: setFunc,          configurable: true      }) : { get: () => any; set: (v: any) => void; configurable: boolean; }
+>{          get: getFunc,          set: setFunc,          configurable: true      } : { get: () => any; set: (v: any) => void; configurable: boolean; }
 
           get: getFunc,
 >get : () => any

tests/baselines/reference/indexerWithTuple.types

@@ -21,7 +21,7 @@ var unionTuple1: [number, string| number] = [10, "foo"];
 
 var unionTuple2: [boolean, string| number] = [true, "foo"]; 
 >unionTuple2 : [boolean, string | number]
->[true, "foo"] : [true, string]
+>[true, "foo"] : [boolean, string]
 >true : true
 >"foo" : "foo"
 

tests/baselines/reference/interfaceContextualType.types

@@ -34,13 +34,13 @@ class Bug {
 >{} : {}
 
         this.values['comments'] = { italic: true };
->this.values['comments'] = { italic: true } : { italic: true; }
+>this.values['comments'] = { italic: true } : { italic: boolean; }
 >this.values['comments'] : IOptions
 >this.values : IMap
 >this : this
 >values : IMap
 >'comments' : "comments"
->{ italic: true } : { italic: true; }
+>{ italic: true } : { italic: boolean; }
 >italic : boolean
 >true : true
     }
@@ -48,15 +48,15 @@ class Bug {
 >shouldBeOK : () => void
 
         this.values = {
->this.values = {            comments: { italic: true }        } : { comments: { italic: true; }; }
+>this.values = {            comments: { italic: true }        } : { comments: { italic: boolean; }; }
 >this.values : IMap
 >this : this
 >values : IMap
->{            comments: { italic: true }        } : { comments: { italic: true; }; }
+>{            comments: { italic: true }        } : { comments: { italic: boolean; }; }
 
             comments: { italic: true }
->comments : { italic: true; }
->{ italic: true } : { italic: true; }
+>comments : { italic: boolean; }
+>{ italic: true } : { italic: boolean; }
 >italic : boolean
 >true : true
 

tests/baselines/reference/interfaceWithPropertyOfEveryType.types

@@ -80,7 +80,7 @@ interface Foo {
 var a: Foo = {
 >a : Foo
 >Foo : Foo
->{    a: 1,    b: '',    c: true,    d: {},    e: null ,    f: [1],    g: {},    h: (x: number) => 1,    i: <T>(x: T) => x,    j: <Foo>null,    k: new C(),    l: f1,    m: M,    n: {},    o: E.A} : { a: number; b: string; c: true; d: {}; e: null; f: number[]; g: {}; h: (x: number) => number; i: <T>(x: T) => T; j: Foo; k: C; l: () => void; m: typeof M; n: {}; o: E; }
+>{    a: 1,    b: '',    c: true,    d: {},    e: null ,    f: [1],    g: {},    h: (x: number) => 1,    i: <T>(x: T) => x,    j: <Foo>null,    k: new C(),    l: f1,    m: M,    n: {},    o: E.A} : { a: number; b: string; c: boolean; d: {}; e: null; f: number[]; g: {}; h: (x: number) => number; i: <T>(x: T) => T; j: Foo; k: C; l: () => void; m: typeof M; n: {}; o: E; }
 
     a: 1,
 >a : number

tests/baselines/reference/isomorphicMappedTypeInference.types

@@ -245,7 +245,7 @@ function f3() {
 >assignBoxified(b, { c: false }) : void
 >assignBoxified : <T>(obj: Boxified<T>, values: T) => void
 >b : { a: Box<number>; b: Box<string>; c: Box<boolean>; }
->{ c: false } : { c: false; }
+>{ c: false } : { c: boolean; }
 >c : boolean
 >false : false
 }

tests/baselines/reference/iterableArrayPattern23.types

@@ -4,11 +4,11 @@ var a: string, b: boolean;
 >b : boolean
 
 [a, b] = { 0: "", 1: true };
->[a, b] = { 0: "", 1: true } : { 0: string; 1: true; }
+>[a, b] = { 0: "", 1: true } : { 0: string; 1: boolean; }
 >[a, b] : [string, boolean]
 >a : string
 >b : boolean
->{ 0: "", 1: true } : { 0: string; 1: true; }
+>{ 0: "", 1: true } : { 0: string; 1: boolean; }
 >"" : ""
 >true : true
 

tests/baselines/reference/iterableArrayPattern24.types

@@ -4,12 +4,12 @@ var a: string, b: boolean[];
 >b : boolean[]
 
 [a, ...b] = { 0: "", 1: true };
->[a, ...b] = { 0: "", 1: true } : { 0: ""; 1: true; }
+>[a, ...b] = { 0: "", 1: true } : { 0: string; 1: boolean; }
 >[a, ...b] : (string | boolean)[]
 >a : string
 >...b : boolean
 >b : boolean[]
->{ 0: "", 1: true } : { 0: ""; 1: true; }
+>{ 0: "", 1: true } : { 0: string; 1: boolean; }
 >"" : ""
 >true : true
 

tests/baselines/reference/iterableArrayPattern29.types

@@ -12,11 +12,11 @@ takeFirstTwoEntries(...new Map([["", true], ["hello", true]]));
 >...new Map([["", true], ["hello", true]]) : [string, boolean]
 >new Map([["", true], ["hello", true]]) : Map<string, boolean>
 >Map : MapConstructor
->[["", true], ["hello", true]] : [string, true][]
->["", true] : [string, true]
+>[["", true], ["hello", true]] : [string, boolean][]
+>["", true] : [string, boolean]
 >"" : ""
 >true : true
->["hello", true] : [string, true]
+>["hello", true] : [string, boolean]
 >"hello" : "hello"
 >true : true
 

tests/baselines/reference/iterableArrayPattern30.types

@@ -6,11 +6,11 @@ const [[k1, v1], [k2, v2]] = new Map([["", true], ["hello", true]])
 >v2 : boolean
 >new Map([["", true], ["hello", true]]) : Map<string, boolean>
 >Map : MapConstructor
->[["", true], ["hello", true]] : [string, true][]
->["", true] : [string, true]
+>[["", true], ["hello", true]] : [string, boolean][]
+>["", true] : [string, boolean]
 >"" : ""
 >true : true
->["hello", true] : [string, true]
+>["hello", true] : [string, boolean]
 >"hello" : "hello"
 >true : true
 

tests/baselines/reference/jsdocParamTagTypeLiteral.types

@@ -149,17 +149,17 @@ function foo5(opts5) {
 foo5([{ help: "help", what: { a: 'a', bad: [{ idea: 'idea', oh: false }] }, unnest: 1 }]);
 >foo5([{ help: "help", what: { a: 'a', bad: [{ idea: 'idea', oh: false }] }, unnest: 1 }]) : void
 >foo5 : (opts5: { help: string; what: { a: string; bad: { idea: string; oh: boolean; }[]; }; unnest: number; }[]) => void
->[{ help: "help", what: { a: 'a', bad: [{ idea: 'idea', oh: false }] }, unnest: 1 }] : { help: string; what: { a: string; bad: { idea: string; oh: false; }[]; }; unnest: number; }[]
->{ help: "help", what: { a: 'a', bad: [{ idea: 'idea', oh: false }] }, unnest: 1 } : { help: string; what: { a: string; bad: { idea: string; oh: false; }[]; }; unnest: number; }
+>[{ help: "help", what: { a: 'a', bad: [{ idea: 'idea', oh: false }] }, unnest: 1 }] : { help: string; what: { a: string; bad: { idea: string; oh: boolean; }[]; }; unnest: number; }[]
+>{ help: "help", what: { a: 'a', bad: [{ idea: 'idea', oh: false }] }, unnest: 1 } : { help: string; what: { a: string; bad: { idea: string; oh: boolean; }[]; }; unnest: number; }
 >help : string
 >"help" : "help"
->what : { a: string; bad: { idea: string; oh: false; }[]; }
->{ a: 'a', bad: [{ idea: 'idea', oh: false }] } : { a: string; bad: { idea: string; oh: false; }[]; }
+>what : { a: string; bad: { idea: string; oh: boolean; }[]; }
+>{ a: 'a', bad: [{ idea: 'idea', oh: false }] } : { a: string; bad: { idea: string; oh: boolean; }[]; }
 >a : string
 >'a' : "a"
->bad : { idea: string; oh: false; }[]
->[{ idea: 'idea', oh: false }] : { idea: string; oh: false; }[]
->{ idea: 'idea', oh: false } : { idea: string; oh: false; }
+>bad : { idea: string; oh: boolean; }[]
+>[{ idea: 'idea', oh: false }] : { idea: string; oh: boolean; }[]
+>{ idea: 'idea', oh: false } : { idea: string; oh: boolean; }
 >idea : string
 >'idea' : "idea"
 >oh : boolean

tests/baselines/reference/keyofAndIndexedAccess.types

@@ -572,7 +572,7 @@ function f31<K extends keyof Shape>(key: K) {
     const shape: Shape = { name: "foo", width: 5, height: 10, visible: true };
 >shape : Shape
 >Shape : Shape
->{ name: "foo", width: 5, height: 10, visible: true } : { name: string; width: number; height: number; visible: true; }
+>{ name: "foo", width: 5, height: 10, visible: true } : { name: string; width: number; height: number; visible: boolean; }
 >name : string
 >"foo" : "foo"
 >width : number
@@ -597,7 +597,7 @@ function f32<K extends "width" | "height">(key: K) {
     const shape: Shape = { name: "foo", width: 5, height: 10, visible: true };
 >shape : Shape
 >Shape : Shape
->{ name: "foo", width: 5, height: 10, visible: true } : { name: string; width: number; height: number; visible: true; }
+>{ name: "foo", width: 5, height: 10, visible: true } : { name: string; width: number; height: number; visible: boolean; }
 >name : string
 >"foo" : "foo"
 >width : number
@@ -952,7 +952,7 @@ function f71(func: <T, U>(x: T, y: U) => Partial<T & U>) {
 >1 : 1
 >b : string
 >"hello" : "hello"
->{ c: true } : { c: true; }
+>{ c: true } : { c: boolean; }
 >c : boolean
 >true : true
 
@@ -999,7 +999,7 @@ function f72(func: <T, U, K extends keyof T | keyof U>(x: T, y: U, k: K) => (T &
 >1 : 1
 >b : string
 >"hello" : "hello"
->{ c: true } : { c: true; }
+>{ c: true } : { c: boolean; }
 >c : boolean
 >true : true
 >'a' : "a"
@@ -1013,7 +1013,7 @@ function f72(func: <T, U, K extends keyof T | keyof U>(x: T, y: U, k: K) => (T &
 >1 : 1
 >b : string
 >"hello" : "hello"
->{ c: true } : { c: true; }
+>{ c: true } : { c: boolean; }
 >c : boolean
 >true : true
 >'b' : "b"
@@ -1027,7 +1027,7 @@ function f72(func: <T, U, K extends keyof T | keyof U>(x: T, y: U, k: K) => (T &
 >1 : 1
 >b : string
 >"hello" : "hello"
->{ c: true } : { c: true; }
+>{ c: true } : { c: boolean; }
 >c : boolean
 >true : true
 >'c' : "c"
@@ -1060,7 +1060,7 @@ function f73(func: <T, U, K extends keyof (T & U)>(x: T, y: U, k: K) => (T & U)[
 >1 : 1
 >b : string
 >"hello" : "hello"
->{ c: true } : { c: true; }
+>{ c: true } : { c: boolean; }
 >c : boolean
 >true : true
 >'a' : "a"
@@ -1074,7 +1074,7 @@ function f73(func: <T, U, K extends keyof (T & U)>(x: T, y: U, k: K) => (T & U)[
 >1 : 1
 >b : string
 >"hello" : "hello"
->{ c: true } : { c: true; }
+>{ c: true } : { c: boolean; }
 >c : boolean
 >true : true
 >'b' : "b"
@@ -1088,7 +1088,7 @@ function f73(func: <T, U, K extends keyof (T & U)>(x: T, y: U, k: K) => (T & U)[
 >1 : 1
 >b : string
 >"hello" : "hello"
->{ c: true } : { c: true; }
+>{ c: true } : { c: boolean; }
 >c : boolean
 >true : true
 >'c' : "c"
@@ -1121,7 +1121,7 @@ function f74(func: <T, U, K extends keyof (T | U)>(x: T, y: U, k: K) => (T | U)[
 >1 : 1
 >b : string
 >"hello" : "hello"
->{ a: 2, b: true } : { a: number; b: true; }
+>{ a: 2, b: true } : { a: number; b: boolean; }
 >a : number
 >2 : 2
 >b : boolean
@@ -1137,7 +1137,7 @@ function f74(func: <T, U, K extends keyof (T | U)>(x: T, y: U, k: K) => (T | U)[
 >1 : 1
 >b : string
 >"hello" : "hello"
->{ a: 2, b: true } : { a: number; b: true; }
+>{ a: 2, b: true } : { a: number; b: boolean; }
 >a : number
 >2 : 2
 >b : boolean

tests/baselines/reference/literalTypes2.types

@@ -501,7 +501,7 @@ function f6() {
 >0 : 0
 >x3 : string
 >"foo" : "foo"
->{ x1: false, x2: 1, x3: "bar" } : { x1?: false; x2?: number; x3?: string; }
+>{ x1: false, x2: 1, x3: "bar" } : { x1?: boolean; x2?: number; x3?: string; }
 >x1 : boolean
 >false : false
 >x2 : number

tests/baselines/reference/mappedTypeErrors.types

@@ -613,7 +613,7 @@ type O = {x: number, y: boolean};
 let o: O = {x: 5, y: false};
 >o : O
 >O : O
->{x: 5, y: false} : { x: number; y: false; }
+>{x: 5, y: false} : { x: number; y: boolean; }
 >x : number
 >5 : 5
 >y : boolean

tests/baselines/reference/objectLiteralNormalization.errors.txt

@@ -4,9 +4,9 @@ tests/cases/conformance/expressions/objectLiterals/objectLiteralNormalization.ts
 tests/cases/conformance/expressions/objectLiterals/objectLiteralNormalization.ts(8,1): error TS2322: Type '{ b: string; }' is not assignable to type '{ a: number; b?: undefined; c?: undefined; } | { a: number; b: string; c?: undefined; } | { a: number; b: string; c: boolean; }'.
   Type '{ b: string; }' is not assignable to type '{ a: number; b: string; c: boolean; }'.
     Property 'a' is missing in type '{ b: string; }'.
-tests/cases/conformance/expressions/objectLiterals/objectLiteralNormalization.ts(9,1): error TS2322: Type '{ c: true; }' is not assignable to type '{ a: number; b?: undefined; c?: undefined; } | { a: number; b: string; c?: undefined; } | { a: number; b: string; c: boolean; }'.
-  Type '{ c: true; }' is not assignable to type '{ a: number; b: string; c: boolean; }'.
-    Property 'a' is missing in type '{ c: true; }'.
+tests/cases/conformance/expressions/objectLiterals/objectLiteralNormalization.ts(9,1): error TS2322: Type '{ c: boolean; }' is not assignable to type '{ a: number; b?: undefined; c?: undefined; } | { a: number; b: string; c?: undefined; } | { a: number; b: string; c: boolean; }'.
+  Type '{ c: boolean; }' is not assignable to type '{ a: number; b: string; c: boolean; }'.
+    Property 'a' is missing in type '{ c: boolean; }'.
 tests/cases/conformance/expressions/objectLiterals/objectLiteralNormalization.ts(17,1): error TS2322: Type '{ a: string; b: number; }' is not assignable to type '{ a: number; b: number; } | { a: string; b?: undefined; } | { a?: undefined; b?: undefined; }'.
   Type '{ a: string; b: number; }' is not assignable to type '{ a?: undefined; b?: undefined; }'.
     Types of property 'a' are incompatible.
@@ -36,9 +36,9 @@ tests/cases/conformance/expressions/objectLiterals/objectLiteralNormalization.ts
 !!! error TS2322:     Property 'a' is missing in type '{ b: string; }'.
     a1 = { c: true };  // Error
     ~~
-!!! error TS2322: Type '{ c: true; }' is not assignable to type '{ a: number; b?: undefined; c?: undefined; } | { a: number; b: string; c?: undefined; } | { a: number; b: string; c: boolean; }'.
-!!! error TS2322:   Type '{ c: true; }' is not assignable to type '{ a: number; b: string; c: boolean; }'.
-!!! error TS2322:     Property 'a' is missing in type '{ c: true; }'.
+!!! error TS2322: Type '{ c: boolean; }' is not assignable to type '{ a: number; b?: undefined; c?: undefined; } | { a: number; b: string; c?: undefined; } | { a: number; b: string; c: boolean; }'.
+!!! error TS2322:   Type '{ c: boolean; }' is not assignable to type '{ a: number; b: string; c: boolean; }'.
+!!! error TS2322:     Property 'a' is missing in type '{ c: boolean; }'.
     
     let a2 = [{ a: 1, b: 2 }, { a: "abc" }, {}][0];
     a2.a;  // string | number | undefined

tests/baselines/reference/objectLiteralNormalization.types

@@ -60,9 +60,9 @@ a1 = { b: "y" };  // Error
 >"y" : "y"
 
 a1 = { c: true };  // Error
->a1 = { c: true } : { c: true; }
+>a1 = { c: true } : { c: boolean; }
 >a1 : { a: number; b?: undefined; c?: undefined; } | { a: number; b: string; c?: undefined; } | { a: number; b: string; c: boolean; }
->{ c: true } : { c: true; }
+>{ c: true } : { c: boolean; }
 >c : boolean
 >true : true
 

tests/baselines/reference/objectLiteralParameterResolution.types

@@ -29,7 +29,7 @@ var s = $.extend({
 >$.extend : { <T>(target: T, ...objs: any[]): T; <T>(deep: boolean, target: T, ...objs: any[]): T; }
 >$ : Foo
 >extend : { <T>(target: T, ...objs: any[]): T; <T>(deep: boolean, target: T, ...objs: any[]): T; }
->{    type: "GET" ,    data: "data" ,    success: wrapSuccessCallback(requestContext, callback) ,    error: wrapErrorCallback(requestContext, errorCallback) ,    dataType: "json" ,    converters: { "text json": "" },    traditional: true ,    timeout: 12,    } : { type: string; data: string; success: any; error: any; dataType: string; converters: { "text json": string; }; traditional: true; timeout: number; }
+>{    type: "GET" ,    data: "data" ,    success: wrapSuccessCallback(requestContext, callback) ,    error: wrapErrorCallback(requestContext, errorCallback) ,    dataType: "json" ,    converters: { "text json": "" },    traditional: true ,    timeout: 12,    } : { type: string; data: string; success: any; error: any; dataType: string; converters: { "text json": string; }; traditional: boolean; timeout: number; }
 
     type: "GET" ,
 >type : string

tests/baselines/reference/objectSpread.types

@@ -31,7 +31,7 @@ let addAfter: { a: number, b: string, c: boolean } =
 >c : boolean
 
     { ...o, c: false }
->{ ...o, c: false } : { c: false; a: number; b: string; }
+>{ ...o, c: false } : { c: boolean; a: number; b: string; }
 >o : { a: number; b: string; }
 >c : boolean
 >false : false
@@ -43,7 +43,7 @@ let addBefore: { a: number, b: string, c: boolean } =
 >c : boolean
 
     { c: false, ...o }
->{ c: false, ...o } : { a: number; b: string; c: false; }
+>{ c: false, ...o } : { a: number; b: string; c: boolean; }
 >c : boolean
 >false : false
 >o : { a: number; b: string; }
@@ -78,11 +78,11 @@ let nested: { a: number, b: boolean, c: string } =
 >c : string
 
     { ...{ a: 3, ...{ b: false, c: 'overriden' } }, c: 'whatever' }
->{ ...{ a: 3, ...{ b: false, c: 'overriden' } }, c: 'whatever' } : { c: string; b: false; a: number; }
->{ a: 3, ...{ b: false, c: 'overriden' } } : { b: false; c: string; a: number; }
+>{ ...{ a: 3, ...{ b: false, c: 'overriden' } }, c: 'whatever' } : { c: string; b: boolean; a: number; }
+>{ a: 3, ...{ b: false, c: 'overriden' } } : { b: boolean; c: string; a: number; }
 >a : number
 >3 : 3
->{ b: false, c: 'overriden' } : { b: false; c: string; }
+>{ b: false, c: 'overriden' } : { b: boolean; c: string; }
 >b : boolean
 >false : false
 >c : string
@@ -148,11 +148,11 @@ let combinedNested: { a: number, b: boolean, c: string, d: string } =
 >d : string
 
     { ...{ a: 4, ...{ b: false, c: 'overriden' } }, d: 'actually new', ...{ a: 5, d: 'maybe new' } }
->{ ...{ a: 4, ...{ b: false, c: 'overriden' } }, d: 'actually new', ...{ a: 5, d: 'maybe new' } } : { a: number; d: string; b: false; c: string; }
->{ a: 4, ...{ b: false, c: 'overriden' } } : { b: false; c: string; a: number; }
+>{ ...{ a: 4, ...{ b: false, c: 'overriden' } }, d: 'actually new', ...{ a: 5, d: 'maybe new' } } : { a: number; d: string; b: boolean; c: string; }
+>{ a: 4, ...{ b: false, c: 'overriden' } } : { b: boolean; c: string; a: number; }
 >a : number
 >4 : 4
->{ b: false, c: 'overriden' } : { b: false; c: string; }
+>{ b: false, c: 'overriden' } : { b: boolean; c: string; }
 >b : boolean
 >false : false
 >c : string
@@ -172,11 +172,11 @@ let combinedNestedChangeType: { a: number, b: boolean, c: number } =
 >c : number
 
     { ...{ a: 1, ...{ b: false, c: 'overriden' } }, c: -1 }
->{ ...{ a: 1, ...{ b: false, c: 'overriden' } }, c: -1 } : { c: number; b: false; a: number; }
->{ a: 1, ...{ b: false, c: 'overriden' } } : { b: false; c: string; a: number; }
+>{ ...{ a: 1, ...{ b: false, c: 'overriden' } }, c: -1 } : { c: number; b: boolean; a: number; }
+>{ a: 1, ...{ b: false, c: 'overriden' } } : { b: boolean; c: string; a: number; }
 >a : number
 >1 : 1
->{ b: false, c: 'overriden' } : { b: false; c: string; }
+>{ b: false, c: 'overriden' } : { b: boolean; c: string; }
 >b : boolean
 >false : false
 >c : string

tests/baselines/reference/objectSpreadNegative.types

@@ -278,7 +278,7 @@ let exclusive: { id: string, a: number, b: string, c: string, d: boolean } =
 >1 : 1
 >b : string
 >'yes' : "yes"
->{ c: 'no', d: false } : { c: string; d: false; }
+>{ c: 'no', d: false } : { c: string; d: boolean; }
 >c : string
 >'no' : "no"
 >d : boolean
@@ -327,7 +327,7 @@ let overwriteId: { id: string, a: number, c: number, d: string } =
     f({ a: 1, id: true }, { c: 1, d: 'no' })
 >f({ a: 1, id: true }, { c: 1, d: 'no' }) : any
 >f : <T, U>(t: T, u: U) => any
->{ a: 1, id: true } : { a: number; id: true; }
+>{ a: 1, id: true } : { a: number; id: boolean; }
 >a : number
 >1 : 1
 >id : boolean

tests/baselines/reference/optionalBindingParameters1.errors.txt

@@ -1,5 +1,5 @@
 tests/cases/conformance/es6/destructuring/optionalBindingParameters1.ts(1,14): error TS2463: A binding pattern parameter cannot be optional in an implementation signature.
-tests/cases/conformance/es6/destructuring/optionalBindingParameters1.ts(7,5): error TS2345: Argument of type '[boolean, number, ""]' is not assignable to parameter of type '[string, number, boolean]'.
+tests/cases/conformance/es6/destructuring/optionalBindingParameters1.ts(7,5): error TS2345: Argument of type '[boolean, number, string]' is not assignable to parameter of type '[string, number, boolean]'.
   Type 'boolean' is not assignable to type 'string'.
 
 
@@ -14,5 +14,5 @@ tests/cases/conformance/es6/destructuring/optionalBindingParameters1.ts(7,5): er
     
     foo([false, 0, ""]);
         ~~~~~~~~~~~~~~
-!!! error TS2345: Argument of type '[boolean, number, ""]' is not assignable to parameter of type '[string, number, boolean]'.
+!!! error TS2345: Argument of type '[boolean, number, string]' is not assignable to parameter of type '[string, number, boolean]'.
 !!! error TS2345:   Type 'boolean' is not assignable to type 'string'.

tests/baselines/reference/optionalBindingParameters1.types

@@ -10,7 +10,7 @@ function foo([x,y,z]?: [string, number, boolean]) {
 foo(["", 0, false]);
 >foo(["", 0, false]) : void
 >foo : ([x, y, z]?: [string, number, boolean]) => void
->["", 0, false] : [string, number, false]
+>["", 0, false] : [string, number, boolean]
 >"" : ""
 >0 : 0
 >false : false

tests/baselines/reference/optionalBindingParameters2.errors.txt

@@ -1,5 +1,5 @@
 tests/cases/conformance/es6/destructuring/optionalBindingParameters2.ts(1,14): error TS2463: A binding pattern parameter cannot be optional in an implementation signature.
-tests/cases/conformance/es6/destructuring/optionalBindingParameters2.ts(7,5): error TS2345: Argument of type '{ x: boolean; y: number; z: ""; }' is not assignable to parameter of type '{ x: string; y: number; z: boolean; }'.
+tests/cases/conformance/es6/destructuring/optionalBindingParameters2.ts(7,5): error TS2345: Argument of type '{ x: boolean; y: number; z: string; }' is not assignable to parameter of type '{ x: string; y: number; z: boolean; }'.
   Types of property 'x' are incompatible.
     Type 'boolean' is not assignable to type 'string'.
 
@@ -15,6 +15,6 @@ tests/cases/conformance/es6/destructuring/optionalBindingParameters2.ts(7,5): er
     
     foo({ x: false, y: 0, z: "" });
         ~~~~~~~~~~~~~~~~~~~~~~~~~
-!!! error TS2345: Argument of type '{ x: boolean; y: number; z: ""; }' is not assignable to parameter of type '{ x: string; y: number; z: boolean; }'.
+!!! error TS2345: Argument of type '{ x: boolean; y: number; z: string; }' is not assignable to parameter of type '{ x: string; y: number; z: boolean; }'.
 !!! error TS2345:   Types of property 'x' are incompatible.
 !!! error TS2345:     Type 'boolean' is not assignable to type 'string'.

tests/baselines/reference/optionalBindingParameters2.types

@@ -13,7 +13,7 @@ function foo({ x, y, z }?: { x: string; y: number; z: boolean }) {
 foo({ x: "", y: 0, z: false });
 >foo({ x: "", y: 0, z: false }) : void
 >foo : ({ x, y, z }?: { x: string; y: number; z: boolean; }) => void
->{ x: "", y: 0, z: false } : { x: string; y: number; z: false; }
+>{ x: "", y: 0, z: false } : { x: string; y: number; z: boolean; }
 >x : string
 >"" : ""
 >y : number

tests/baselines/reference/optionalBindingParametersInOverloads1.errors.txt

@@ -1,4 +1,4 @@
-tests/cases/conformance/es6/destructuring/optionalBindingParametersInOverloads1.ts(8,5): error TS2345: Argument of type '[boolean, number, ""]' is not assignable to parameter of type '[string, number, boolean]'.
+tests/cases/conformance/es6/destructuring/optionalBindingParametersInOverloads1.ts(8,5): error TS2345: Argument of type '[boolean, number, string]' is not assignable to parameter of type '[string, number, boolean]'.
   Type 'boolean' is not assignable to type 'string'.
 
 
@@ -12,5 +12,5 @@ tests/cases/conformance/es6/destructuring/optionalBindingParametersInOverloads1.
     
     foo([false, 0, ""]);
         ~~~~~~~~~~~~~~
-!!! error TS2345: Argument of type '[boolean, number, ""]' is not assignable to parameter of type '[string, number, boolean]'.
+!!! error TS2345: Argument of type '[boolean, number, string]' is not assignable to parameter of type '[string, number, boolean]'.
 !!! error TS2345:   Type 'boolean' is not assignable to type 'string'.

tests/baselines/reference/optionalBindingParametersInOverloads1.types

@@ -14,7 +14,7 @@ function foo(...rest: any[]) {
 foo(["", 0, false]);
 >foo(["", 0, false]) : any
 >foo : ([x, y, z]?: [string, number, boolean]) => any
->["", 0, false] : [string, number, false]
+>["", 0, false] : [string, number, boolean]
 >"" : ""
 >0 : 0
 >false : false

tests/baselines/reference/optionalBindingParametersInOverloads2.errors.txt

@@ -1,4 +1,4 @@
-tests/cases/conformance/es6/destructuring/optionalBindingParametersInOverloads2.ts(8,5): error TS2345: Argument of type '{ x: boolean; y: number; z: ""; }' is not assignable to parameter of type '{ x: string; y: number; z: boolean; }'.
+tests/cases/conformance/es6/destructuring/optionalBindingParametersInOverloads2.ts(8,5): error TS2345: Argument of type '{ x: boolean; y: number; z: string; }' is not assignable to parameter of type '{ x: string; y: number; z: boolean; }'.
   Types of property 'x' are incompatible.
     Type 'boolean' is not assignable to type 'string'.
 
@@ -13,6 +13,6 @@ tests/cases/conformance/es6/destructuring/optionalBindingParametersInOverloads2.
     
     foo({ x: false, y: 0, z: "" });
         ~~~~~~~~~~~~~~~~~~~~~~~~~
-!!! error TS2345: Argument of type '{ x: boolean; y: number; z: ""; }' is not assignable to parameter of type '{ x: string; y: number; z: boolean; }'.
+!!! error TS2345: Argument of type '{ x: boolean; y: number; z: string; }' is not assignable to parameter of type '{ x: string; y: number; z: boolean; }'.
 !!! error TS2345:   Types of property 'x' are incompatible.
 !!! error TS2345:     Type 'boolean' is not assignable to type 'string'.

tests/baselines/reference/optionalBindingParametersInOverloads2.types

@@ -17,7 +17,7 @@ function foo(...rest: any[]) {
 foo({ x: "", y: 0, z: false });
 >foo({ x: "", y: 0, z: false }) : any
 >foo : ({ x, y, z }?: { x: string; y: number; z: boolean; }) => any
->{ x: "", y: 0, z: false } : { x: string; y: number; z: false; }
+>{ x: "", y: 0, z: false } : { x: string; y: number; z: boolean; }
 >x : string
 >"" : ""
 >y : number

tests/baselines/reference/overloadResolutionTest1.errors.txt

@@ -1,10 +1,10 @@
-tests/cases/compiler/overloadResolutionTest1.ts(7,16): error TS2345: Argument of type '{ a: "s"; }[]' is not assignable to parameter of type '{ a: boolean; }[]'.
-  Type '{ a: "s"; }' is not assignable to type '{ a: boolean; }'.
+tests/cases/compiler/overloadResolutionTest1.ts(7,16): error TS2345: Argument of type '{ a: string; }[]' is not assignable to parameter of type '{ a: boolean; }[]'.
+  Type '{ a: string; }' is not assignable to type '{ a: boolean; }'.
     Types of property 'a' are incompatible.
-      Type '"s"' is not assignable to type 'boolean'.
-tests/cases/compiler/overloadResolutionTest1.ts(18,15): error TS2345: Argument of type '{ a: "s"; }' is not assignable to parameter of type '{ a: boolean; }'.
+      Type 'string' is not assignable to type 'boolean'.
+tests/cases/compiler/overloadResolutionTest1.ts(18,15): error TS2345: Argument of type '{ a: string; }' is not assignable to parameter of type '{ a: boolean; }'.
   Types of property 'a' are incompatible.
-    Type '"s"' is not assignable to type 'boolean'.
+    Type 'string' is not assignable to type 'boolean'.
 tests/cases/compiler/overloadResolutionTest1.ts(24,14): error TS2345: Argument of type '{ a: boolean; }' is not assignable to parameter of type '{ a: string; }'.
   Types of property 'a' are incompatible.
     Type 'boolean' is not assignable to type 'string'.
@@ -19,10 +19,10 @@ tests/cases/compiler/overloadResolutionTest1.ts(24,14): error TS2345: Argument o
     var x11 = foo([{a:0}]); // works
     var x111 = foo([{a:"s"}]); // error - does not match any signature
                    ~~~~~~~~~
-!!! error TS2345: Argument of type '{ a: "s"; }[]' is not assignable to parameter of type '{ a: boolean; }[]'.
-!!! error TS2345:   Type '{ a: "s"; }' is not assignable to type '{ a: boolean; }'.
+!!! error TS2345: Argument of type '{ a: string; }[]' is not assignable to parameter of type '{ a: boolean; }[]'.
+!!! error TS2345:   Type '{ a: string; }' is not assignable to type '{ a: boolean; }'.
 !!! error TS2345:     Types of property 'a' are incompatible.
-!!! error TS2345:       Type '"s"' is not assignable to type 'boolean'.
+!!! error TS2345:       Type 'string' is not assignable to type 'boolean'.
     var x1111 = foo([{a:null}]); // works - ambiguous call is resolved to be the first in the overload set so this returns a string
     
     
@@ -35,9 +35,9 @@ tests/cases/compiler/overloadResolutionTest1.ts(24,14): error TS2345: Argument o
     var x3 = foo2({a:true}); // works
     var x4 = foo2({a:"s"}); // error
                   ~~~~~~~
-!!! error TS2345: Argument of type '{ a: "s"; }' is not assignable to parameter of type '{ a: boolean; }'.
+!!! error TS2345: Argument of type '{ a: string; }' is not assignable to parameter of type '{ a: boolean; }'.
 !!! error TS2345:   Types of property 'a' are incompatible.
-!!! error TS2345:     Type '"s"' is not assignable to type 'boolean'.
+!!! error TS2345:     Type 'string' is not assignable to type 'boolean'.
     
     
     function foo4(bar:{a:number;}):number;

tests/baselines/reference/overloadResolutionTest1.types

@@ -19,8 +19,8 @@ var x1 = foo([{a:true}]); // works
 >x1 : number
 >foo([{a:true}]) : number
 >foo : { (bar: { a: number; }[]): string; (bar: { a: boolean; }[]): number; }
->[{a:true}] : { a: true; }[]
->{a:true} : { a: true; }
+>[{a:true}] : { a: boolean; }[]
+>{a:true} : { a: boolean; }
 >a : boolean
 >true : true
 
@@ -81,7 +81,7 @@ var x3 = foo2({a:true}); // works
 >x3 : number
 >foo2({a:true}) : number
 >foo2 : { (bar: { a: number; }): string; (bar: { a: boolean; }): number; }
->{a:true} : { a: true; }
+>{a:true} : { a: boolean; }
 >a : boolean
 >true : true
 

tests/baselines/reference/parserUsingConstructorAsIdentifier.types

@@ -97,7 +97,7 @@
 >constructor : any
 >prototype : any
 >"constructor" : "constructor"
->{ value: constructor, writable: true, configurable: true, enumerable: true } : { value: any; writable: true; configurable: true; enumerable: true; }
+>{ value: constructor, writable: true, configurable: true, enumerable: true } : { value: any; writable: boolean; configurable: boolean; enumerable: boolean; }
 >value : any
 >constructor : any
 >writable : boolean

tests/baselines/reference/parserharness.types

@@ -1581,7 +1581,7 @@ module Harness {
                     var metadata: IScenarioMetadata = { id: undefined, desc: this.description, pass: false, bugs: assert.bugIds };
 >metadata : IScenarioMetadata
 >IScenarioMetadata : IScenarioMetadata
->{ id: undefined, desc: this.description, pass: false, bugs: assert.bugIds } : { id: undefined; desc: any; pass: false; bugs: any; }
+>{ id: undefined, desc: this.description, pass: false, bugs: assert.bugIds } : { id: undefined; desc: any; pass: boolean; bugs: any; }
 >id : undefined
 >undefined : undefined
 >desc : any

tests/baselines/reference/privacyCheckAnonymousFunctionParameter.types

@@ -31,7 +31,7 @@ module Query {
         return fromDoWhile(test => {
 >fromDoWhile(test => {            return true;        }) : Iterator<{}>
 >fromDoWhile : <T>(doWhile: (test: Iterator<T>) => boolean) => Iterator<T>
->test => {            return true;        } : (test: Iterator<{}>) => true
+>test => {            return true;        } : (test: Iterator<{}>) => boolean
 >test : Iterator<{}>
 
             return true;

tests/baselines/reference/symbolProperty21.errors.txt

@@ -1,4 +1,4 @@
-tests/cases/conformance/es6/Symbols/symbolProperty21.ts(10,5): error TS2345: Argument of type '{ [Symbol.isConcatSpreadable]: string; [Symbol.toPrimitive]: number; [Symbol.unscopables]: true; }' is not assignable to parameter of type 'I<boolean, string>'.
+tests/cases/conformance/es6/Symbols/symbolProperty21.ts(10,5): error TS2345: Argument of type '{ [Symbol.isConcatSpreadable]: string; [Symbol.toPrimitive]: number; [Symbol.unscopables]: boolean; }' is not assignable to parameter of type 'I<boolean, string>'.
   Object literal may only specify known properties, and '[Symbol.toPrimitive]' does not exist in type 'I<boolean, string>'.
 
 
@@ -14,7 +14,7 @@ tests/cases/conformance/es6/Symbols/symbolProperty21.ts(10,5): error TS2345: Arg
         [Symbol.isConcatSpreadable]: "",
         [Symbol.toPrimitive]: 0,
         ~~~~~~~~~~~~~~~~~~~~~~~
-!!! error TS2345: Argument of type '{ [Symbol.isConcatSpreadable]: string; [Symbol.toPrimitive]: number; [Symbol.unscopables]: true; }' is not assignable to parameter of type 'I<boolean, string>'.
+!!! error TS2345: Argument of type '{ [Symbol.isConcatSpreadable]: string; [Symbol.toPrimitive]: number; [Symbol.unscopables]: boolean; }' is not assignable to parameter of type 'I<boolean, string>'.
 !!! error TS2345:   Object literal may only specify known properties, and '[Symbol.toPrimitive]' does not exist in type 'I<boolean, string>'.
         [Symbol.unscopables]: true
     });

tests/baselines/reference/targetTypeArgs.types

@@ -35,7 +35,7 @@ foo(function(x) { x });
 >["hello"] : string[]
 >"hello" : "hello"
 >every : (callbackfn: (value: string, index: number, array: string[]) => boolean, thisArg?: any) => boolean
->function(v,i,a) {return true;} : (v: string, i: number, a: string[]) => true
+>function(v,i,a) {return true;} : (v: string, i: number, a: string[]) => boolean
 >v : string
 >i : number
 >a : string[]
@@ -47,7 +47,7 @@ foo(function(x) { x });
 >[1] : number[]
 >1 : 1
 >every : (callbackfn: (value: number, index: number, array: number[]) => boolean, thisArg?: any) => boolean
->function(v,i,a) {return true;} : (v: number, i: number, a: number[]) => true
+>function(v,i,a) {return true;} : (v: number, i: number, a: number[]) => boolean
 >v : number
 >i : number
 >a : number[]
@@ -59,7 +59,7 @@ foo(function(x) { x });
 >[1] : number[]
 >1 : 1
 >every : (callbackfn: (value: number, index: number, array: number[]) => boolean, thisArg?: any) => boolean
->function(v,i,a) {return true;} : (v: number, i: number, a: number[]) => true
+>function(v,i,a) {return true;} : (v: number, i: number, a: number[]) => boolean
 >v : number
 >i : number
 >a : number[]
@@ -71,7 +71,7 @@ foo(function(x) { x });
 >["s"] : string[]
 >"s" : "s"
 >every : (callbackfn: (value: string, index: number, array: string[]) => boolean, thisArg?: any) => boolean
->function(v,i,a) {return true;} : (v: string, i: number, a: string[]) => true
+>function(v,i,a) {return true;} : (v: string, i: number, a: string[]) => boolean
 >v : string
 >i : number
 >a : string[]

tests/baselines/reference/thisTypeInFunctions2.types

@@ -58,7 +58,7 @@ declare function simple(arg: SimpleInterface): void;
 extend1({
 >extend1({    init() {        this // this: IndexedWithThis because of contextual typing.        // this.mine        this.willDestroy    },    mine: 12,    foo() {        this.url; // this: any because 'foo' matches the string indexer        this.willDestroy;    }}) : void
 >extend1 : (args: IndexedWithThis) => void
->{    init() {        this // this: IndexedWithThis because of contextual typing.        // this.mine        this.willDestroy    },    mine: 12,    foo() {        this.url; // this: any because 'foo' matches the string indexer        this.willDestroy;    }} : { init(this: IndexedWithThis): void; mine: 12; foo(this: any): void; }
+>{    init() {        this // this: IndexedWithThis because of contextual typing.        // this.mine        this.willDestroy    },    mine: 12,    foo() {        this.url; // this: any because 'foo' matches the string indexer        this.willDestroy;    }} : { init(this: IndexedWithThis): void; mine: number; foo(this: any): void; }
 
     init() {
 >init : (this: IndexedWithThis) => void