Merge branch 'master' into release-2.1

Jakefile.js

@@ -930,7 +930,7 @@ function runConsoleTests(defaultReporter, runInParallel) {
     }
 
     if (tests && tests.toLocaleLowerCase() === "rwc") {
-        testTimeout = 400000;
+        testTimeout = 800000;
     }
 
     colors = process.env.colors || process.env.color;
@@ -1086,12 +1086,10 @@ task("tests-debug", ["setDebugMode", "tests"]);
 // Makes the test results the new baseline
 desc("Makes the most recent test results the new baseline, overwriting the old baseline");
 task("baseline-accept", function () {
-    acceptBaseline("");
+    acceptBaseline(localBaseline, refBaseline);
 });
 
-function acceptBaseline(containerFolder) {
-    var sourceFolder = path.join(localBaseline, containerFolder);
-    var targetFolder = path.join(refBaseline, containerFolder);
+function acceptBaseline(sourceFolder, targetFolder) {
     console.log('Accept baselines from ' + sourceFolder + ' to ' + targetFolder);
     var files = fs.readdirSync(sourceFolder);
     var deleteEnding = '.delete';
@@ -1115,12 +1113,12 @@ function acceptBaseline(containerFolder) {
 
 desc("Makes the most recent rwc test results the new baseline, overwriting the old baseline");
 task("baseline-accept-rwc", function () {
-    acceptBaseline("rwc");
+    acceptBaseline(localRwcBaseline, refRwcBaseline);
 });
 
 desc("Makes the most recent test262 test results the new baseline, overwriting the old baseline");
 task("baseline-accept-test262", function () {
-    acceptBaseline("test262");
+    acceptBaseline(localTest262Baseline, refTest262Baseline);
 });
 
 

package.json

@@ -75,8 +75,7 @@
         "through2": "latest",
         "travis-fold": "latest",
         "ts-node": "latest",
-        "tsd": "latest",
-        "tslint": "4.0.0-dev.0",
+        "tslint": "4.0.0-dev.2",
         "typescript": "^2.1"
     },
     "scripts": {

scripts/parallel-lint.js

@@ -1,26 +1,29 @@
-var Linter = require("tslint");
+var tslint = require("tslint");
 var fs = require("fs");
 
 function getLinterOptions() {
     return {
-        configuration: require("../tslint.json"),
         formatter: "prose",
         formattersDirectory: undefined,
         rulesDirectory: "built/local/tslint"
     };
 }
-
-function lintFileContents(options, path, contents) {
-    var ll = new Linter(path, contents, options);
-    return ll.lint();
+function getLinterConfiguration() {
+    return require("../tslint.json");
 }
 
-function lintFileAsync(options, path, cb) {
+function lintFileContents(options, configuration, path, contents) {
+    var ll = new tslint.Linter(options);
+    ll.lint(path, contents, configuration);
+    return ll.getResult();
+}
+
+function lintFileAsync(options, configuration, path, cb) {
     fs.readFile(path, "utf8", function (err, contents) {
         if (err) {
             return cb(err);
         }
-        var result = lintFileContents(options, path, contents);
+        var result = lintFileContents(options, configuration, path, contents);
         cb(undefined, result);
     });
 }
@@ -30,7 +33,8 @@ process.on("message", function (data) {
         case "file":
             var target = data.name;
             var lintOptions = getLinterOptions();
-            lintFileAsync(lintOptions, target, function (err, result) {
+            var lintConfiguration = getLinterConfiguration();
+            lintFileAsync(lintOptions, lintConfiguration, target, function (err, result) {
                 if (err) {
                     process.send({ kind: "error", error: err.toString() });
                     return;

scripts/tslint/booleanTriviaRule.ts

@@ -1,4 +1,4 @@
-import * as Lint from "tslint/lib/lint";
+import * as Lint from "tslint/lib";
 import * as ts from "typescript";
 
 export class Rule extends Lint.Rules.AbstractRule {

scripts/tslint/nextLineRule.ts

@@ -1,4 +1,4 @@
-import * as Lint from "tslint/lib/lint";
+import * as Lint from "tslint/lib";
 import * as ts from "typescript";
 
 const OPTION_CATCH = "check-catch";

scripts/tslint/noInOperatorRule.ts

@@ -1,4 +1,4 @@
-import * as Lint from "tslint/lib/lint";
+import * as Lint from "tslint/lib";
 import * as ts from "typescript";
 
 

scripts/tslint/noIncrementDecrementRule.ts

@@ -1,4 +1,4 @@
-import * as Lint from "tslint/lib/lint";
+import * as Lint from "tslint/lib";
 import * as ts from "typescript";
 
 

scripts/tslint/noTypeAssertionWhitespaceRule.ts

@@ -1,4 +1,4 @@
-import * as Lint from "tslint/lib/lint";
+import * as Lint from "tslint/lib";
 import * as ts from "typescript";
 
 

scripts/tslint/objectLiteralSurroundingSpaceRule.ts

@@ -1,4 +1,4 @@
-import * as Lint from "tslint/lib/lint";
+import * as Lint from "tslint/lib";
 import * as ts from "typescript";
 
 

scripts/tslint/preferConstRule.ts

@@ -1,4 +1,4 @@
-import * as Lint from "tslint/lib/lint";
+import * as Lint from "tslint/lib";
 import * as ts from "typescript";
 
 export class Rule extends Lint.Rules.AbstractRule {

scripts/tslint/typeOperatorSpacingRule.ts

@@ -1,4 +1,4 @@
-import * as Lint from "tslint/lib/lint";
+import * as Lint from "tslint/lib";
 import * as ts from "typescript";
 
 

src/compiler/binder.ts

@@ -599,8 +599,8 @@ namespace ts {
             // Binding of JsDocComment should be done before the current block scope container changes.
             // because the scope of JsDocComment should not be affected by whether the current node is a
             // container or not.
-            if (isInJavaScriptFile(node) && node.jsDocComments) {
-                forEach(node.jsDocComments, bind);
+            if (isInJavaScriptFile(node) && node.jsDoc) {
+                forEach(node.jsDoc, bind);
             }
             if (checkUnreachable(node)) {
                 bindEachChild(node);

src/compiler/checker.ts

@@ -142,7 +142,6 @@ namespace ts {
         const voidType = createIntrinsicType(TypeFlags.Void, "void");
         const neverType = createIntrinsicType(TypeFlags.Never, "never");
         const silentNeverType = createIntrinsicType(TypeFlags.Never, "never");
-        const stringOrNumberType = getUnionType([stringType, numberType]);
 
         const emptyObjectType = createAnonymousType(undefined, emptySymbols, emptyArray, emptyArray, undefined, undefined);
 
@@ -3156,38 +3155,10 @@ namespace ts {
         }
 
         function getTypeForVariableLikeDeclarationFromJSDocComment(declaration: VariableLikeDeclaration) {
-            const jsDocType = getJSDocTypeForVariableLikeDeclarationFromJSDocComment(declaration);
-            if (jsDocType) {
-                return getTypeFromTypeNode(jsDocType);
+            const jsdocType = getJSDocType(declaration);
+            if (jsdocType) {
+                return getTypeFromTypeNode(jsdocType);
             }
-        }
-
-        function getJSDocTypeForVariableLikeDeclarationFromJSDocComment(declaration: VariableLikeDeclaration): JSDocType {
-            // First, see if this node has an @type annotation on it directly.
-            const typeTag = getJSDocTypeTag(declaration);
-            if (typeTag && typeTag.typeExpression) {
-                return typeTag.typeExpression.type;
-            }
-
-            if (declaration.kind === SyntaxKind.VariableDeclaration &&
-                declaration.parent.kind === SyntaxKind.VariableDeclarationList &&
-                declaration.parent.parent.kind === SyntaxKind.VariableStatement) {
-
-                // @type annotation might have been on the variable statement, try that instead.
-                const annotation = getJSDocTypeTag(declaration.parent.parent);
-                if (annotation && annotation.typeExpression) {
-                    return annotation.typeExpression.type;
-                }
-            }
-            else if (declaration.kind === SyntaxKind.Parameter) {
-                // If it's a parameter, see if the parent has a jsdoc comment with an @param
-                // annotation.
-                const paramTag = getCorrespondingJSDocParameterTag(<ParameterDeclaration>declaration);
-                if (paramTag && paramTag.typeExpression) {
-                    return paramTag.typeExpression.type;
-                }
-            }
-
             return undefined;
         }
 
@@ -3217,9 +3188,11 @@ namespace ts {
                 }
             }
 
-            // A variable declared in a for..in statement is always of type string
+            // A variable declared in a for..in statement is of type string, or of type keyof T when the
+            // right hand expression is of a type parameter type.
             if (declaration.parent.parent.kind === SyntaxKind.ForInStatement) {
-                return stringType;
+                const indexType = getIndexType(checkNonNullExpression((<ForInStatement>declaration.parent.parent).expression));
+                return indexType.flags & TypeFlags.Index ? indexType : stringType;
             }
 
             if (declaration.parent.parent.kind === SyntaxKind.ForOfStatement) {
@@ -3455,9 +3428,9 @@ namespace ts {
                     declaration.kind === SyntaxKind.PropertyAccessExpression && declaration.parent.kind === SyntaxKind.BinaryExpression) {
                     // Use JS Doc type if present on parent expression statement
                     if (declaration.flags & NodeFlags.JavaScriptFile) {
-                        const typeTag = getJSDocTypeTag(declaration.parent);
-                        if (typeTag && typeTag.typeExpression) {
-                            return links.type = getTypeFromTypeNode(typeTag.typeExpression.type);
+                        const jsdocType = getJSDocType(declaration.parent);
+                        if (jsdocType) {
+                            return links.type = getTypeFromTypeNode(jsdocType);
                         }
                     }
                     const declaredTypes = map(symbol.declarations,
@@ -4688,7 +4661,6 @@ namespace ts {
                 t.flags & TypeFlags.NumberLike ? globalNumberType :
                 t.flags & TypeFlags.BooleanLike ? globalBooleanType :
                 t.flags & TypeFlags.ESSymbol ? getGlobalESSymbolType() :
-                t.flags & TypeFlags.Index ? stringOrNumberType :
                 t;
         }
 
@@ -4901,15 +4873,16 @@ namespace ts {
                 if (node.type && node.type.kind === SyntaxKind.JSDocOptionalType) {
                     return true;
                 }
+                const paramTags = getJSDocParameterTags(node);
+                if (paramTags) {
+                    for (const paramTag of paramTags) {
+                        if (paramTag.isBracketed) {
+                            return true;
+                        }
 
-                const paramTag = getCorrespondingJSDocParameterTag(node);
-                if (paramTag) {
-                    if (paramTag.isBracketed) {
-                        return true;
-                    }
-
-                    if (paramTag.typeExpression) {
-                        return paramTag.typeExpression.type.kind === SyntaxKind.JSDocOptionalType;
+                        if (paramTag.typeExpression) {
+                            return paramTag.typeExpression.type.kind === SyntaxKind.JSDocOptionalType;
+                        }
                     }
                 }
             }
@@ -5920,8 +5893,7 @@ namespace ts {
         function getIndexType(type: Type): Type {
             return type.flags & TypeFlags.TypeParameter ? getIndexTypeForTypeParameter(<TypeParameter>type) :
                 getObjectFlags(type) & ObjectFlags.Mapped ? getConstraintTypeFromMappedType(<MappedType>type) :
-                type.flags & TypeFlags.Any || getIndexInfoOfType(type, IndexKind.String) ? stringOrNumberType :
-                getIndexInfoOfType(type, IndexKind.Number) ? getUnionType([numberType, getLiteralTypeFromPropertyNames(type)]) :
+                type.flags & TypeFlags.Any || getIndexInfoOfType(type, IndexKind.String) ? stringType :
                 getLiteralTypeFromPropertyNames(type);
         }
 
@@ -6039,11 +6011,11 @@ namespace ts {
                 const id = objectType.id + "," + indexType.id;
                 return indexedAccessTypes[id] || (indexedAccessTypes[id] = createIndexedAccessType(objectType, indexType));
             }
-            const apparentType = getApparentType(objectType);
+            const apparentObjectType = getApparentType(objectType);
             if (indexType.flags & TypeFlags.Union && !(indexType.flags & TypeFlags.Primitive)) {
                 const propTypes: Type[] = [];
                 for (const t of (<UnionType>indexType).types) {
-                    const propType = getPropertyTypeForIndexType(apparentType, t, accessNode, /*cacheSymbol*/ false);
+                    const propType = getPropertyTypeForIndexType(apparentObjectType, t, accessNode, /*cacheSymbol*/ false);
                     if (propType === unknownType) {
                         return unknownType;
                     }
@@ -6051,7 +6023,7 @@ namespace ts {
                 }
                 return getUnionType(propTypes);
             }
-            return getPropertyTypeForIndexType(apparentType, indexType, accessNode, /*cacheSymbol*/ true);
+            return getPropertyTypeForIndexType(apparentObjectType, indexType, accessNode, /*cacheSymbol*/ true);
         }
 
         function getTypeFromIndexedAccessTypeNode(node: IndexedAccessTypeNode) {
@@ -7123,13 +7095,6 @@ namespace ts {
 
                 if (isSimpleTypeRelatedTo(source, target, relation, reportErrors ? reportError : undefined)) return Ternary.True;
 
-                if (source.flags & TypeFlags.Index) {
-                    // A keyof T is related to a union type containing both string and number
-                    if (maybeTypeOfKind(target, TypeFlags.String) && maybeTypeOfKind(target, TypeFlags.Number)) {
-                        return Ternary.True;
-                    }
-                }
-
                 if (getObjectFlags(source) & ObjectFlags.ObjectLiteral && source.flags & TypeFlags.FreshLiteral) {
                     if (hasExcessProperties(<FreshObjectLiteralType>source, target, reportErrors)) {
                         if (reportErrors) {
@@ -10392,9 +10357,9 @@ namespace ts {
         }
 
         function getTypeForThisExpressionFromJSDoc(node: Node) {
-            const typeTag = getJSDocTypeTag(node);
-            if (typeTag && typeTag.typeExpression && typeTag.typeExpression.type && typeTag.typeExpression.type.kind === SyntaxKind.JSDocFunctionType) {
-                const jsDocFunctionType = <JSDocFunctionType>typeTag.typeExpression.type;
+            const jsdocType = getJSDocType(node);
+            if (jsdocType && jsdocType.kind === SyntaxKind.JSDocFunctionType) {
+                const jsDocFunctionType = <JSDocFunctionType>jsdocType;
                 if (jsDocFunctionType.parameters.length > 0 && jsDocFunctionType.parameters[0].type.kind === SyntaxKind.JSDocThisType) {
                     return getTypeFromTypeNode(jsDocFunctionType.parameters[0].type);
                 }
@@ -13628,7 +13593,7 @@ namespace ts {
         // the destructured type into the contained binding elements.
         function assignBindingElementTypes(node: VariableLikeDeclaration) {
             if (isBindingPattern(node.name)) {
-                for (const element of (<BindingPattern>node.name).elements) {
+                for (const element of node.name.elements) {
                     if (!isOmittedExpression(element)) {
                         if (element.name.kind === SyntaxKind.Identifier) {
                             getSymbolLinks(getSymbolOfNode(element)).type = getTypeForBindingElement(element);
@@ -14256,7 +14221,7 @@ namespace ts {
             if (!isTypeAnyOrAllConstituentTypesHaveKind(leftType, TypeFlags.StringLike | TypeFlags.NumberLike | TypeFlags.ESSymbol)) {
                 error(left, Diagnostics.The_left_hand_side_of_an_in_expression_must_be_of_type_any_string_number_or_symbol);
             }
-            if (!isTypeAnyOrAllConstituentTypesHaveKind(rightType, TypeFlags.Object | TypeFlags.TypeParameter)) {
+            if (!isTypeAnyOrAllConstituentTypesHaveKind(rightType, TypeFlags.Object | TypeFlags.TypeParameter | TypeFlags.IndexedAccess)) {
                 error(right, Diagnostics.The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter);
             }
             return booleanType;
@@ -15650,7 +15615,7 @@ namespace ts {
             const type = <MappedType>getTypeFromMappedTypeNode(node);
             const constraintType = getConstraintTypeFromMappedType(type);
             const keyType = constraintType.flags & TypeFlags.TypeParameter ? getApparentTypeOfTypeParameter(<TypeParameter>constraintType) : constraintType;
-            checkTypeAssignableTo(keyType, stringOrNumberType, node.typeParameter.constraint);
+            checkTypeAssignableTo(keyType, stringType, node.typeParameter.constraint);
         }
 
         function isPrivateWithinAmbient(node: Node): boolean {
@@ -17161,7 +17126,7 @@ namespace ts {
             const rightType = checkNonNullExpression(node.expression);
             // unknownType is returned i.e. if node.expression is identifier whose name cannot be resolved
             // in this case error about missing name is already reported - do not report extra one
-            if (!isTypeAnyOrAllConstituentTypesHaveKind(rightType, TypeFlags.Object | TypeFlags.TypeParameter)) {
+            if (!isTypeAnyOrAllConstituentTypesHaveKind(rightType, TypeFlags.Object | TypeFlags.TypeParameter | TypeFlags.IndexedAccess)) {
                 error(node.expression, Diagnostics.The_right_hand_side_of_a_for_in_statement_must_be_of_type_any_an_object_type_or_a_type_parameter);
             }
 

src/compiler/commandLineParser.ts

@@ -951,8 +951,8 @@ namespace ts {
                 errors.push(createCompilerDiagnostic(Diagnostics.Unknown_option_excludes_Did_you_mean_exclude));
             }
             else {
-                // By default, exclude common package folders and the outDir
-                excludeSpecs = ["node_modules", "bower_components", "jspm_packages"];
+                // If no includes were specified, exclude common package folders and the outDir
+                excludeSpecs = includeSpecs ? [] : ["node_modules", "bower_components", "jspm_packages"];
 
                 const outDir = json["compilerOptions"] && json["compilerOptions"]["outDir"];
                 if (outDir) {

src/compiler/declarationEmitter.ts

@@ -371,7 +371,7 @@ namespace ts {
 
         function writeJsDocComments(declaration: Node) {
             if (declaration) {
-                const jsDocComments = getJsDocCommentsFromText(declaration, currentText);
+                const jsDocComments = getJSDocCommentRanges(declaration, currentText);
                 emitNewLineBeforeLeadingComments(currentLineMap, writer, declaration, jsDocComments);
                 // jsDoc comments are emitted at /*leading comment1 */space/*leading comment*/space
                 emitComments(currentText, currentLineMap, writer, jsDocComments, /*leadingSeparator*/ false, /*trailingSeparator*/ true, newLine, writeCommentRange);

src/compiler/parser.ts

@@ -681,7 +681,7 @@ namespace ts {
 
 
         function addJSDocComment<T extends Node>(node: T): T {
-            const comments = getJsDocCommentsFromText(node, sourceFile.text);
+            const comments = getJSDocCommentRanges(node, sourceFile.text);
             if (comments) {
                 for (const comment of comments) {
                     const jsDoc = JSDocParser.parseJSDocComment(node, comment.pos, comment.end - comment.pos);
@@ -689,10 +689,10 @@ namespace ts {
                         continue;
                     }
 
-                    if (!node.jsDocComments) {
-                        node.jsDocComments = [];
+                    if (!node.jsDoc) {
+                        node.jsDoc = [];
                     }
-                    node.jsDocComments.push(jsDoc);
+                    node.jsDoc.push(jsDoc);
                 }
             }
 
@@ -719,11 +719,11 @@ namespace ts {
                     const saveParent = parent;
                     parent = n;
                     forEachChild(n, visitNode);
-                    if (n.jsDocComments) {
-                        for (const jsDocComment of n.jsDocComments) {
-                            jsDocComment.parent = n;
-                            parent = jsDocComment;
-                            forEachChild(jsDocComment, visitNode);
+                    if (n.jsDoc) {
+                        for (const jsDoc of n.jsDoc) {
+                            jsDoc.parent = n;
+                            parent = jsDoc;
+                            forEachChild(jsDoc, visitNode);
                         }
                     }
                     parent = saveParent;
@@ -6954,8 +6954,8 @@ namespace ts {
                 }
 
                 forEachChild(node, visitNode, visitArray);
-                if (node.jsDocComments) {
-                    for (const jsDocComment of node.jsDocComments) {
+                if (node.jsDoc) {
+                    for (const jsDocComment of node.jsDoc) {
                         forEachChild(jsDocComment, visitNode, visitArray);
                     }
                 }

src/compiler/transformers/es2015.ts

@@ -1306,7 +1306,9 @@ namespace ts {
                             createAssignment(
                                 createElementAccess(
                                     expressionName,
-                                    createSubtract(temp, createLiteral(restIndex))
+                                    restIndex === 0
+                                        ? temp
+                                        : createSubtract(temp, createLiteral(restIndex))
                                 ),
                                 createElementAccess(createIdentifier("arguments"), temp)
                             ),

src/compiler/types.ts

@@ -497,7 +497,8 @@ namespace ts {
         parent?: Node;                                  // Parent node (initialized by binding)
         /* @internal */ original?: Node;                // The original node if this is an updated node.
         /* @internal */ startsOnNewLine?: boolean;      // Whether a synthesized node should start on a new line (used by transforms).
-        /* @internal */ jsDocComments?: JSDoc[];        // JSDoc for the node, if it has any.
+        /* @internal */ jsDoc?: JSDoc[];                // JSDoc that directly precedes this node
+        /* @internal */ jsDocCache?: (JSDoc | JSDocTag)[]; // All JSDoc that applies to the node, including parent docs and @param tags
         /* @internal */ symbol?: Symbol;                // Symbol declared by node (initialized by binding)
         /* @internal */ locals?: SymbolTable;           // Locals associated with node (initialized by binding)
         /* @internal */ nextContainer?: Node;           // Next container in declaration order (initialized by binding)
@@ -2789,7 +2790,7 @@ namespace ts {
         Intrinsic = Any | String | Number | Boolean | BooleanLiteral | ESSymbol | Void | Undefined | Null | Never,
         /* @internal */
         Primitive = String | Number | Boolean | Enum | ESSymbol | Void | Undefined | Null | Literal,
-        StringLike = String | StringLiteral,
+        StringLike = String | StringLiteral | Index,
         NumberLike = Number | NumberLiteral | Enum | EnumLiteral,
         BooleanLike = Boolean | BooleanLiteral,
         EnumLike = Enum | EnumLiteral,

src/compiler/utilities.ts

@@ -239,7 +239,7 @@ namespace ts {
         return !nodeIsMissing(node);
     }
 
-    export function getTokenPosOfNode(node: Node, sourceFile?: SourceFile, includeJsDocComment?: boolean): number {
+    export function getTokenPosOfNode(node: Node, sourceFile?: SourceFile, includeJsDoc?: boolean): number {
         // With nodes that have no width (i.e. 'Missing' nodes), we actually *don't*
         // want to skip trivia because this will launch us forward to the next token.
         if (nodeIsMissing(node)) {
@@ -250,8 +250,8 @@ namespace ts {
             return skipTrivia((sourceFile || getSourceFileOfNode(node)).text, node.pos, /*stopAfterLineBreak*/ false, /*stopAtComments*/ true);
         }
 
-        if (includeJsDocComment && node.jsDocComments && node.jsDocComments.length > 0) {
-            return getTokenPosOfNode(node.jsDocComments[0]);
+        if (includeJsDoc && node.jsDoc && node.jsDoc.length > 0) {
+            return getTokenPosOfNode(node.jsDoc[0]);
         }
 
         // For a syntax list, it is possible that one of its children has JSDocComment nodes, while
@@ -259,7 +259,7 @@ namespace ts {
         // trivia for the list, we may have skipped the JSDocComment as well. So we should process its
         // first child to determine the actual position of its first token.
         if (node.kind === SyntaxKind.SyntaxList && (<SyntaxList>node)._children.length > 0) {
-            return getTokenPosOfNode((<SyntaxList>node)._children[0], sourceFile, includeJsDocComment);
+            return getTokenPosOfNode((<SyntaxList>node)._children[0], sourceFile, includeJsDoc);
         }
 
         return skipTrivia((sourceFile || getSourceFileOfNode(node)).text, node.pos);
@@ -624,25 +624,18 @@ namespace ts {
         return getLeadingCommentRanges(text, node.pos);
     }
 
-    export function getJsDocComments(node: Node, sourceFileOfNode: SourceFile) {
-        return getJsDocCommentsFromText(node, sourceFileOfNode.text);
-    }
-
-    export function getJsDocCommentsFromText(node: Node, text: string) {
+    export function getJSDocCommentRanges(node: Node, text: string) {
         const commentRanges = (node.kind === SyntaxKind.Parameter ||
             node.kind === SyntaxKind.TypeParameter ||
             node.kind === SyntaxKind.FunctionExpression ||
             node.kind === SyntaxKind.ArrowFunction) ?
             concatenate(getTrailingCommentRanges(text, node.pos), getLeadingCommentRanges(text, node.pos)) :
             getLeadingCommentRangesOfNodeFromText(node, text);
-        return filter(commentRanges, isJsDocComment);
-
-        function isJsDocComment(comment: CommentRange) {
-            // True if the comment starts with '/**' but not if it is '/**/'
-            return text.charCodeAt(comment.pos + 1) === CharacterCodes.asterisk &&
-                text.charCodeAt(comment.pos + 2) === CharacterCodes.asterisk &&
-                text.charCodeAt(comment.pos + 3) !== CharacterCodes.slash;
-        }
+        // True if the comment starts with '/**' but not if it is '/**/'
+        return filter(commentRanges, comment =>
+            text.charCodeAt(comment.pos + 1) === CharacterCodes.asterisk &&
+            text.charCodeAt(comment.pos + 2) === CharacterCodes.asterisk &&
+            text.charCodeAt(comment.pos + 3) !== CharacterCodes.slash);
     }
 
     export let fullTripleSlashReferencePathRegEx = /^(\/\/\/\s*<reference\s+path\s*=\s*)('|")(.+?)\2.*?\/>/;
@@ -1423,57 +1416,42 @@ namespace ts {
             (<JSDocFunctionType>node).parameters[0].type.kind === SyntaxKind.JSDocConstructorType;
     }
 
-    function getJSDocTag(node: Node, kind: SyntaxKind, checkParentVariableStatement: boolean): JSDocTag {
-        if (!node) {
-            return undefined;
-        }
-
-        const jsDocTags = getJSDocTags(node, checkParentVariableStatement);
-        if (!jsDocTags) {
-            return undefined;
-        }
-
-        for (const tag of jsDocTags) {
-            if (tag.kind === kind) {
-                return tag;
-            }
-        }
+    export function getCommentsFromJSDoc(node: Node): string[] {
+        return map(getJSDocs(node), doc => doc.comment);
     }
 
-    function append<T>(previous: T[] | undefined, additional: T[] | undefined): T[] | undefined {
-        if (additional) {
-            if (!previous) {
-                previous = [];
-            }
-            for (const x of additional) {
-                previous.push(x);
-            }
-        }
-        return previous;
-    }
-
-    export function getJSDocComments(node: Node, checkParentVariableStatement: boolean): string[] {
-        return getJSDocs(node, checkParentVariableStatement, docs => map(docs, doc => doc.comment), tags => map(tags, tag => tag.comment));
-    }
-
-    function getJSDocTags(node: Node, checkParentVariableStatement: boolean): JSDocTag[] {
-        return getJSDocs(node, checkParentVariableStatement, docs => {
+    function getJSDocTags(node: Node, kind: SyntaxKind): JSDocTag[] {
+        const docs = getJSDocs(node);
+        if (docs) {
             const result: JSDocTag[] = [];
             for (const doc of docs) {
-                if (doc.tags) {
-                    result.push(...doc.tags);
+                if (doc.kind === SyntaxKind.JSDocParameterTag) {
+                    if (doc.kind === kind) {
+                        result.push(doc as JSDocTag);
+                    }
+                }
+                else {
+                    result.push(...filter((doc as JSDoc).tags, tag => tag.kind === kind));
                 }
             }
             return result;
-        }, tags => tags);
+        }
     }
 
-    function getJSDocs<T>(node: Node, checkParentVariableStatement: boolean, getDocs: (docs: JSDoc[]) => T[], getTags: (tags: JSDocTag[]) => T[]): T[] {
-        // TODO: Get rid of getJsDocComments and friends (note the lowercase 's' in Js)
-        // TODO: A lot of this work should be cached, maybe. I guess it's only used in services right now...
-        let result: T[] = undefined;
-        // prepend documentation from parent sources
-        if (checkParentVariableStatement) {
+    function getFirstJSDocTag(node: Node, kind: SyntaxKind): JSDocTag {
+        return node && firstOrUndefined(getJSDocTags(node, kind));
+    }
+
+   function getJSDocs(node: Node): (JSDoc | JSDocTag)[] {
+        let cache: (JSDoc | JSDocTag)[] = node.jsDocCache;
+        if (!cache) {
+            getJSDocsWorker(node);
+            node.jsDocCache = cache;
+        }
+        return cache;
+
+        function getJSDocsWorker(node: Node) {
+            const parent = node.parent;
             // Try to recognize this pattern when node is initializer of variable declaration and JSDoc comments are on containing variable statement.
             // /**
             //   * @param {number} name
@@ -1481,68 +1459,55 @@ namespace ts {
             //   */
             // var x = function(name) { return name.length; }
             const isInitializerOfVariableDeclarationInStatement =
-                isVariableLike(node.parent) &&
-                (node.parent).initializer === node &&
-                node.parent.parent.parent.kind === SyntaxKind.VariableStatement;
+                isVariableLike(parent) &&
+                parent.initializer === node &&
+                parent.parent.parent.kind === SyntaxKind.VariableStatement;
             const isVariableOfVariableDeclarationStatement = isVariableLike(node) &&
-                node.parent.parent.kind === SyntaxKind.VariableStatement;
-
+                parent.parent.kind === SyntaxKind.VariableStatement;
             const variableStatementNode =
-                isInitializerOfVariableDeclarationInStatement ? node.parent.parent.parent :
-                    isVariableOfVariableDeclarationStatement ? node.parent.parent :
-                        undefined;
+                isInitializerOfVariableDeclarationInStatement ? parent.parent.parent :
+                isVariableOfVariableDeclarationStatement ? parent.parent :
+                undefined;
             if (variableStatementNode) {
-                result = append(result, getJSDocs(variableStatementNode, checkParentVariableStatement, getDocs, getTags));
-            }
-            if (node.kind === SyntaxKind.ModuleDeclaration &&
-                node.parent && node.parent.kind === SyntaxKind.ModuleDeclaration) {
-                result = append(result, getJSDocs(node.parent, checkParentVariableStatement, getDocs, getTags));
+                getJSDocsWorker(variableStatementNode);
             }
 
             // Also recognize when the node is the RHS of an assignment expression
-            const parent = node.parent;
             const isSourceOfAssignmentExpressionStatement =
                 parent && parent.parent &&
                 parent.kind === SyntaxKind.BinaryExpression &&
                 (parent as BinaryExpression).operatorToken.kind === SyntaxKind.EqualsToken &&
                 parent.parent.kind === SyntaxKind.ExpressionStatement;
             if (isSourceOfAssignmentExpressionStatement) {
-                result = append(result, getJSDocs(parent.parent, checkParentVariableStatement, getDocs, getTags));
+                getJSDocsWorker(parent.parent);
             }
 
+            const isModuleDeclaration = node.kind === SyntaxKind.ModuleDeclaration &&
+                parent && parent.kind === SyntaxKind.ModuleDeclaration;
             const isPropertyAssignmentExpression = parent && parent.kind === SyntaxKind.PropertyAssignment;
-            if (isPropertyAssignmentExpression) {
-                result = append(result, getJSDocs(parent, checkParentVariableStatement, getDocs, getTags));
+            if (isModuleDeclaration || isPropertyAssignmentExpression) {
+                getJSDocsWorker(parent);
             }
 
             // Pull parameter comments from declaring function as well
             if (node.kind === SyntaxKind.Parameter) {
-                const paramTags = getJSDocParameterTag(node as ParameterDeclaration, checkParentVariableStatement);
-                if (paramTags) {
-                    result = append(result, getTags(paramTags));
-                }
+                cache = concatenate(cache, getJSDocParameterTags(node));
             }
-        }
 
-        if (isVariableLike(node) && node.initializer) {
-            result = append(result, getJSDocs(node.initializer, /*checkParentVariableStatement*/ false, getDocs, getTags));
-        }
-
-        if (node.jsDocComments) {
-            if (result) {
-                result = append(result, getDocs(node.jsDocComments));
+            if (isVariableLike(node) && node.initializer) {
+                cache = concatenate(cache, node.initializer.jsDoc);
             }
-            else {
-                return getDocs(node.jsDocComments);
-            }
-        }
 
-        return result;
+            cache = concatenate(cache, node.jsDoc);
+        }
     }
 
-    function getJSDocParameterTag(param: ParameterDeclaration, checkParentVariableStatement: boolean): JSDocTag[] {
+    export function getJSDocParameterTags(param: Node): JSDocParameterTag[] {
+        if (!isParameter(param)) {
+            return undefined;
+        }
         const func = param.parent as FunctionLikeDeclaration;
-        const tags = getJSDocTags(func, checkParentVariableStatement);
+        const tags = getJSDocTags(func, SyntaxKind.JSDocParameterTag) as JSDocParameterTag[];
         if (!param.name) {
             // this is an anonymous jsdoc param from a `function(type1, type2): type3` specification
             const i = func.parameters.indexOf(param);
@@ -1553,10 +1518,7 @@ namespace ts {
         }
         else if (param.name.kind === SyntaxKind.Identifier) {
             const name = (param.name as Identifier).text;
-            const paramTags = filter(tags, tag => tag.kind === SyntaxKind.JSDocParameterTag && (tag as JSDocParameterTag).parameterName.text === name);
-            if (paramTags) {
-                return paramTags;
-            }
+            return filter(tags, tag => tag.kind === SyntaxKind.JSDocParameterTag && tag.parameterName.text === name);
         }
         else {
             // TODO: it's a destructured parameter, so it should look up an "object type" series of multiple lines
@@ -1565,39 +1527,24 @@ namespace ts {
         }
     }
 
-    export function getJSDocTypeTag(node: Node): JSDocTypeTag {
-        return <JSDocTypeTag>getJSDocTag(node, SyntaxKind.JSDocTypeTag, /*checkParentVariableStatement*/ false);
-    }
-
-    export function getJSDocReturnTag(node: Node): JSDocReturnTag {
-        return <JSDocReturnTag>getJSDocTag(node, SyntaxKind.JSDocReturnTag, /*checkParentVariableStatement*/ true);
-    }
-
-    export function getJSDocTemplateTag(node: Node): JSDocTemplateTag {
-        return <JSDocTemplateTag>getJSDocTag(node, SyntaxKind.JSDocTemplateTag, /*checkParentVariableStatement*/ false);
-    }
-
-    export function getCorrespondingJSDocParameterTag(parameter: ParameterDeclaration): JSDocParameterTag {
-        if (parameter.name && parameter.name.kind === SyntaxKind.Identifier) {
-            // If it's a parameter, see if the parent has a jsdoc comment with an @param
-            // annotation.
-            const parameterName = (<Identifier>parameter.name).text;
-
-            const jsDocTags = getJSDocTags(parameter.parent, /*checkParentVariableStatement*/ true);
-            if (!jsDocTags) {
-                return undefined;
-            }
-            for (const tag of jsDocTags) {
-                if (tag.kind === SyntaxKind.JSDocParameterTag) {
-                    const parameterTag = <JSDocParameterTag>tag;
-                    if (parameterTag.parameterName.text === parameterName) {
-                        return parameterTag;
-                    }
-                }
+    export function getJSDocType(node: Node): JSDocType {
+        let tag: JSDocTypeTag | JSDocParameterTag = getFirstJSDocTag(node, SyntaxKind.JSDocTypeTag) as JSDocTypeTag;
+        if (!tag && node.kind === SyntaxKind.Parameter) {
+            const paramTags = getJSDocParameterTags(node);
+            if (paramTags) {
+                tag = find(paramTags, tag => !!tag.typeExpression);
             }
         }
 
-        return undefined;
+        return tag && tag.typeExpression && tag.typeExpression.type;
+    }
+
+    export function getJSDocReturnTag(node: Node): JSDocReturnTag {
+        return getFirstJSDocTag(node, SyntaxKind.JSDocReturnTag) as JSDocReturnTag;
+    }
+
+    export function getJSDocTemplateTag(node: Node): JSDocTemplateTag {
+        return getFirstJSDocTag(node, SyntaxKind.JSDocTemplateTag) as JSDocTemplateTag;
     }
 
     export function hasRestParameter(s: SignatureDeclaration): boolean {
@@ -1610,14 +1557,11 @@ namespace ts {
 
     export function isRestParameter(node: ParameterDeclaration) {
         if (node && (node.flags & NodeFlags.JavaScriptFile)) {
-            if (node.type && node.type.kind === SyntaxKind.JSDocVariadicType) {
+            if (node.type && node.type.kind === SyntaxKind.JSDocVariadicType ||
+                forEach(getJSDocParameterTags(node),
+                        t => t.typeExpression && t.typeExpression.type.kind === SyntaxKind.JSDocVariadicType)) {
                 return true;
             }
-
-            const paramTag = getCorrespondingJSDocParameterTag(node);
-            if (paramTag && paramTag.typeExpression) {
-                return paramTag.typeExpression.type.kind === SyntaxKind.JSDocVariadicType;
-            }
         }
         return isDeclaredRestParam(node);
     }

src/harness/harness.ts

@@ -2015,7 +2015,7 @@ namespace Harness {
 
     export function isDefaultLibraryFile(filePath: string): boolean {
         // We need to make sure that the filePath is prefixed with "lib." not just containing "lib." and end with ".d.ts"
-        const fileName = ts.getBaseFileName(filePath);
+        const fileName = ts.getBaseFileName(ts.normalizeSlashes(filePath));
         return ts.startsWith(fileName, "lib.") && ts.endsWith(fileName, ".d.ts");
     }
 

src/harness/rwcRunner.ts

@@ -199,7 +199,7 @@ namespace RWC {
                     }
                     // Do not include the library in the baselines to avoid noise
                     const baselineFiles = inputFiles.concat(otherFiles).filter(f => !Harness.isDefaultLibraryFile(f.unitName));
-                    const errors = compilerResult.errors.filter(e => !Harness.isDefaultLibraryFile(e.file.fileName));
+                    const errors = compilerResult.errors.filter(e => e.file && !Harness.isDefaultLibraryFile(e.file.fileName));
                     return Harness.Compiler.getErrorBaseline(baselineFiles, errors);
                 }, baselineOpts);
             });

src/harness/unittests/matchFiles.ts

@@ -89,8 +89,6 @@ namespace ts {
         "c:/dev/g.min.js/.g/g.ts"
     ]);
 
-    const defaultExcludes = ["node_modules", "bower_components", "jspm_packages"];
-
     function assertParsed(actual: ts.ParsedCommandLine, expected: ts.ParsedCommandLine): void {
         assert.deepEqual(actual.fileNames, expected.fileNames);
         assert.deepEqual(actual.wildcardDirectories, expected.wildcardDirectories);
@@ -98,6 +96,23 @@ namespace ts {
     }
 
     describe("matchFiles", () => {
+        it("with defaults", () => {
+            const json = {};
+            const expected: ts.ParsedCommandLine = {
+                options: {},
+                errors: [],
+                fileNames: [
+                    "c:/dev/a.ts",
+                    "c:/dev/b.ts"
+                ],
+                wildcardDirectories: {
+                    "c:/dev": ts.WatchDirectoryFlags.Recursive
+                },
+            };
+            const actual = ts.parseJsonConfigFileContent(json, caseInsensitiveCommonFoldersHost, caseInsensitiveBasePath);
+            assertParsed(actual, expected);
+        });
+
         describe("with literal file list", () => {
             it("without exclusions", () => {
                 const json = {
@@ -192,7 +207,7 @@ namespace ts {
                     options: {},
                     errors: [
                         ts.createCompilerDiagnostic(ts.Diagnostics.No_inputs_were_found_in_config_file_0_Specified_include_paths_were_1_and_exclude_paths_were_2,
-                            caseInsensitiveTsconfigPath, JSON.stringify(json.include), JSON.stringify(defaultExcludes))
+                            caseInsensitiveTsconfigPath, JSON.stringify(json.include), "[]")
                     ],
                     fileNames: [],
                     wildcardDirectories: {},
@@ -211,7 +226,7 @@ namespace ts {
                     options: {},
                     errors: [
                         ts.createCompilerDiagnostic(ts.Diagnostics.No_inputs_were_found_in_config_file_0_Specified_include_paths_were_1_and_exclude_paths_were_2,
-                            caseInsensitiveTsconfigPath, JSON.stringify(json.include), JSON.stringify(defaultExcludes))
+                            caseInsensitiveTsconfigPath, JSON.stringify(json.include), "[]")
                     ],
                     fileNames: [],
                     wildcardDirectories: {},
@@ -330,7 +345,10 @@ namespace ts {
                     errors: [],
                     fileNames: [
                         "c:/dev/a.ts",
-                        "c:/dev/b.ts"
+                        "c:/dev/b.ts",
+                        "c:/dev/bower_components/a.ts",
+                        "c:/dev/jspm_packages/a.ts",
+                        "c:/dev/node_modules/a.ts"
                     ],
                     wildcardDirectories: {},
                 };
@@ -372,8 +390,7 @@ namespace ts {
                         "node_modules/a.ts",
                         "bower_components/a.ts",
                         "jspm_packages/a.ts"
-                    ],
-                    exclude: <string[]>[]
+                    ]
                 };
                 const expected: ts.ParsedCommandLine = {
                     options: {},
@@ -530,7 +547,7 @@ namespace ts {
                     options: {},
                     errors: [
                         ts.createCompilerDiagnostic(ts.Diagnostics.No_inputs_were_found_in_config_file_0_Specified_include_paths_were_1_and_exclude_paths_were_2,
-                            caseInsensitiveTsconfigPath, JSON.stringify(json.include), JSON.stringify(defaultExcludes))
+                            caseInsensitiveTsconfigPath, JSON.stringify(json.include), "[]")
                     ],
                     fileNames: [],
                     wildcardDirectories: {
@@ -600,7 +617,10 @@ namespace ts {
                     options: {},
                     errors: [],
                     fileNames: [
-                        "c:/dev/a.ts"
+                        "c:/dev/a.ts",
+                        "c:/dev/bower_components/a.ts",
+                        "c:/dev/jspm_packages/a.ts",
+                        "c:/dev/node_modules/a.ts"
                     ],
                     wildcardDirectories: {
                         "c:/dev": ts.WatchDirectoryFlags.Recursive
@@ -671,7 +691,7 @@ namespace ts {
                     },
                     errors: [
                         ts.createCompilerDiagnostic(ts.Diagnostics.No_inputs_were_found_in_config_file_0_Specified_include_paths_were_1_and_exclude_paths_were_2,
-                            caseInsensitiveTsconfigPath, JSON.stringify(json.include), JSON.stringify(defaultExcludes))
+                            caseInsensitiveTsconfigPath, JSON.stringify(json.include), "[]")
                     ],
                     fileNames: [],
                     wildcardDirectories: {
@@ -980,7 +1000,7 @@ namespace ts {
                         errors: [
                             ts.createCompilerDiagnostic(ts.Diagnostics.File_specification_cannot_end_in_a_recursive_directory_wildcard_Asterisk_Asterisk_Colon_0, "**"),
                             ts.createCompilerDiagnostic(ts.Diagnostics.No_inputs_were_found_in_config_file_0_Specified_include_paths_were_1_and_exclude_paths_were_2,
-                                caseInsensitiveTsconfigPath, JSON.stringify(json.include), JSON.stringify(defaultExcludes))
+                                caseInsensitiveTsconfigPath, JSON.stringify(json.include), "[]")
                         ],
                         fileNames: [],
                         wildcardDirectories: {}
@@ -1022,7 +1042,7 @@ namespace ts {
                         errors: [
                             ts.createCompilerDiagnostic(ts.Diagnostics.File_specification_cannot_contain_multiple_recursive_directory_wildcards_Asterisk_Asterisk_Colon_0, "**/x/**/*"),
                             ts.createCompilerDiagnostic(ts.Diagnostics.No_inputs_were_found_in_config_file_0_Specified_include_paths_were_1_and_exclude_paths_were_2,
-                                caseInsensitiveTsconfigPath, JSON.stringify(json.include), JSON.stringify(defaultExcludes))
+                                caseInsensitiveTsconfigPath, JSON.stringify(json.include), "[]")
                         ],
                         fileNames: [],
                         wildcardDirectories: {}
@@ -1071,7 +1091,7 @@ namespace ts {
                         errors: [
                             ts.createCompilerDiagnostic(ts.Diagnostics.File_specification_cannot_contain_a_parent_directory_that_appears_after_a_recursive_directory_wildcard_Asterisk_Asterisk_Colon_0, "**/../*"),
                             ts.createCompilerDiagnostic(ts.Diagnostics.No_inputs_were_found_in_config_file_0_Specified_include_paths_were_1_and_exclude_paths_were_2,
-                                caseInsensitiveTsconfigPath, JSON.stringify(json.include), JSON.stringify(defaultExcludes))
+                                caseInsensitiveTsconfigPath, JSON.stringify(json.include), "[]")
                         ],
                         fileNames: [],
                         wildcardDirectories: {}
@@ -1091,7 +1111,7 @@ namespace ts {
                         errors: [
                             ts.createCompilerDiagnostic(ts.Diagnostics.File_specification_cannot_contain_a_parent_directory_that_appears_after_a_recursive_directory_wildcard_Asterisk_Asterisk_Colon_0, "**/y/../*"),
                             ts.createCompilerDiagnostic(ts.Diagnostics.No_inputs_were_found_in_config_file_0_Specified_include_paths_were_1_and_exclude_paths_were_2,
-                                caseInsensitiveTsconfigPath, JSON.stringify(json.include), JSON.stringify(defaultExcludes))
+                                caseInsensitiveTsconfigPath, JSON.stringify(json.include), "[]")
                         ],
                         fileNames: [],
                         wildcardDirectories: {}

src/lib/es5.d.ts

@@ -1367,7 +1367,7 @@ type Pick<T, K extends keyof T> = {
 /**
  * Construct a type with a set of properties K of type T
  */
-type Record<K extends string | number, T> = {
+type Record<K extends string, T> = {
     [P in K]: T;
 }
 

src/server/server.ts

@@ -31,6 +31,7 @@ namespace ts.server {
                     os.tmpdir();
                 break;
             case "linux":
+            case "android":
                 basePath = (os.homedir && os.homedir()) ||
                     process.env.HOME ||
                     ((process.env.LOGNAME || process.env.USER) && `/home/${process.env.LOGNAME || process.env.USER}`) ||
@@ -603,4 +604,4 @@ namespace ts.server {
     (process as any).noAsar = true;
     // Start listening
     ioSession.listen();
-}
+}

src/services/codefixes/importFixes.ts

@@ -1,4 +1,4 @@
-// /* @internal */
+// /* @internal */
 // namespace ts.codefix {
 
 //     type ImportCodeActionKind = "CodeChange" | "InsertingIntoExistingImport" | "NewImport";
@@ -145,7 +145,7 @@
 //                     if (localSymbol && localSymbol.name === name && checkSymbolHasMeaning(localSymbol, currentTokenMeaning)) {
 //                         // check if this symbol is already used
 //                         const symbolId = getUniqueSymbolId(localSymbol);
-//                         symbolIdActionMap.addActions(symbolId, getCodeActionForImport(moduleSymbol, /*isDefaultExport*/ true));
+//                         symbolIdActionMap.addActions(symbolId, getCodeActionForImport(moduleSymbol, /*isDefault*/ true));
 //                     }
 //                 }
 
@@ -483,7 +483,7 @@
 //                                 const normalizedTypeRoots = map(typeRoots, typeRoot => toPath(typeRoot, /*basePath*/ undefined, getCanonicalFileName));
 //                                 for (const typeRoot of normalizedTypeRoots) {
 //                                     if (startsWith(moduleFileName, typeRoot)) {
-//                                         let relativeFileName = moduleFileName.substring(typeRoot.length + 1);
+//                                         const relativeFileName = moduleFileName.substring(typeRoot.length + 1);
 //                                         return removeExtensionAndIndexPostFix(relativeFileName);
 //                                     }
 //                                 }
@@ -588,4 +588,4 @@
 //             }
 //         }
 //     });
-// }
+// }

src/services/jsDoc.ts

@@ -52,7 +52,7 @@ namespace ts.JsDoc {
         // from Array<T> - Array<string> and Array<number>
         const documentationComment = <SymbolDisplayPart[]>[];
         forEachUnique(declarations, declaration => {
-            const comments = getJSDocComments(declaration, /*checkParentVariableStatement*/ true);
+            const comments = getCommentsFromJSDoc(declaration);
             if (!comments) {
                 return;
             }

src/services/navigationBar.ts

@@ -225,8 +225,8 @@ namespace ts.NavigationBar {
                 break;
 
             default:
-                forEach(node.jsDocComments, jsDocComment => {
-                    forEach(jsDocComment.tags, tag => {
+                forEach(node.jsDoc, jsDoc => {
+                    forEach(jsDoc.tags, tag => {
                         if (tag.kind === SyntaxKind.JSDocTypedefTag) {
                             addLeafNode(tag);
                         }

src/services/services.ts

@@ -45,7 +45,7 @@ namespace ts {
         public end: number;
         public flags: NodeFlags;
         public parent: Node;
-        public jsDocComments: JSDoc[];
+        public jsDoc: JSDoc[];
         public original: Node;
         public transformFlags: TransformFlags;
         private _children: Node[];
@@ -154,8 +154,8 @@ namespace ts {
                     pos = nodes.end;
                 };
                 // jsDocComments need to be the first children
-                if (this.jsDocComments) {
-                    for (const jsDocComment of this.jsDocComments) {
+                if (this.jsDoc) {
+                    for (const jsDocComment of this.jsDoc) {
                         processNode(jsDocComment);
                     }
                 }
@@ -1975,9 +1975,9 @@ namespace ts {
                     break;
                 default:
                     forEachChild(node, walk);
-                    if (node.jsDocComments) {
-                        for (const jsDocComment of node.jsDocComments) {
-                            forEachChild(jsDocComment, walk);
+                    if (node.jsDoc) {
+                        for (const jsDoc of node.jsDoc) {
+                            forEachChild(jsDoc, walk);
                         }
                     }
             }

src/services/utilities.ts

@@ -951,10 +951,10 @@ namespace ts {
         }
 
         if (node) {
-            if (node.jsDocComments) {
-                for (const jsDocComment of node.jsDocComments) {
-                    if (jsDocComment.tags) {
-                        for (const tag of jsDocComment.tags) {
+            if (node.jsDoc) {
+                for (const jsDoc of node.jsDoc) {
+                    if (jsDoc.tags) {
+                        for (const tag of jsDoc.tags) {
                             if (tag.pos <= position && position <= tag.end) {
                                 return tag;
                             }

tests/baselines/reference/accessorWithRestParam.js

@@ -13,7 +13,7 @@ var C = (function () {
         set: function () {
             var v = [];
             for (var _i = 0; _i < arguments.length; _i++) {
-                v[_i - 0] = arguments[_i];
+                v[_i] = arguments[_i];
             }
         },
         enumerable: true,
@@ -23,7 +23,7 @@ var C = (function () {
         set: function () {
             var v2 = [];
             for (var _i = 0; _i < arguments.length; _i++) {
-                v2[_i - 0] = arguments[_i];
+                v2[_i] = arguments[_i];
             }
         },
         enumerable: true,

tests/baselines/reference/assignmentCompatWithCallSignaturesWithRestParameters.js

@@ -52,14 +52,14 @@ a = function () { return 1; }; // ok, same number of required params
 a = function () {
     var args = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        args[_i - 0] = arguments[_i];
+        args[_i] = arguments[_i];
     }
     return 1;
 }; // ok, same number of required params
 a = function () {
     var args = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        args[_i - 0] = arguments[_i];
+        args[_i] = arguments[_i];
     }
     return 1;
 }; // error, type mismatch
@@ -72,7 +72,7 @@ a2 = function () { return 1; }; // ok, fewer required params
 a2 = function () {
     var args = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        args[_i - 0] = arguments[_i];
+        args[_i] = arguments[_i];
     }
     return 1;
 }; // ok, fewer required params

tests/baselines/reference/baseTypeAfterDerivedType.js

@@ -23,7 +23,7 @@ var Derived2 = (function () {
     Derived2.prototype.method = function () {
         var args = [];
         for (var _i = 0; _i < arguments.length; _i++) {
-            args[_i - 0] = arguments[_i];
+            args[_i] = arguments[_i];
         }
     };
     return Derived2;

tests/baselines/reference/checkSuperCallBeforeThisAccessing5.js

@@ -17,7 +17,7 @@ var Based = (function () {
     function Based() {
         var arg = [];
         for (var _i = 0; _i < arguments.length; _i++) {
-            arg[_i - 0] = arguments[_i];
+            arg[_i] = arguments[_i];
         }
     }
     return Based;

tests/baselines/reference/checkSuperCallBeforeThisAccessing6.js

@@ -20,7 +20,7 @@ var Base = (function () {
     function Base() {
         var arg = [];
         for (var _i = 0; _i < arguments.length; _i++) {
-            arg[_i - 0] = arguments[_i];
+            arg[_i] = arguments[_i];
         }
     }
     return Base;

tests/baselines/reference/checkSuperCallBeforeThisAccessing8.js

@@ -20,7 +20,7 @@ var Base = (function () {
     function Base() {
         var arg = [];
         for (var _i = 0; _i < arguments.length; _i++) {
-            arg[_i - 0] = arguments[_i];
+            arg[_i] = arguments[_i];
         }
     }
     return Base;

tests/baselines/reference/collisionArgumentsArrowFunctions.js

@@ -37,7 +37,7 @@ var f1NoError = function (arguments) {
 var f2 = function () {
     var restParameters = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        restParameters[_i - 0] = arguments[_i];
+        restParameters[_i] = arguments[_i];
     }
     var arguments = 10; // No Error
 };

tests/baselines/reference/collisionArgumentsClassConstructor.js

@@ -118,7 +118,7 @@ var c2 = (function () {
     function c2() {
         var restParameters = [];
         for (var _i = 0; _i < arguments.length; _i++) {
-            restParameters[_i - 0] = arguments[_i];
+            restParameters[_i] = arguments[_i];
         }
         var arguments = 10; // no error
     }

tests/baselines/reference/collisionArgumentsClassMethod.js

@@ -94,7 +94,7 @@ var c3 = (function () {
     c3.prototype.foo = function () {
         var restParameters = [];
         for (var _i = 0; _i < arguments.length; _i++) {
-            restParameters[_i - 0] = arguments[_i];
+            restParameters[_i] = arguments[_i];
         }
         var arguments = 10; // no error
     };

tests/baselines/reference/collisionArgumentsFunction.js

@@ -66,7 +66,7 @@ function f1NoError(arguments) {
 function f3() {
     var restParameters = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        restParameters[_i - 0] = arguments[_i];
+        restParameters[_i] = arguments[_i];
     }
     var arguments = 10; // no error
 }

tests/baselines/reference/collisionArgumentsFunctionExpressions.js

@@ -56,7 +56,7 @@ function foo() {
     function f3() {
         var restParameters = [];
         for (var _i = 0; _i < arguments.length; _i++) {
-            restParameters[_i - 0] = arguments[_i];
+            restParameters[_i] = arguments[_i];
         }
         var arguments = 10; // no error
     }

tests/baselines/reference/collisionRestParameterArrowFunctions.js

@@ -27,7 +27,7 @@ var f1NoError = function (_i) {
 var f2 = function () {
     var restParameters = [];
     for (var _a = 0; _a < arguments.length; _a++) {
-        restParameters[_a - 0] = arguments[_a];
+        restParameters[_a] = arguments[_a];
     }
     var _i = 10; // No Error
 };

tests/baselines/reference/collisionRestParameterClassConstructor.js

@@ -88,7 +88,7 @@ var c2 = (function () {
     function c2() {
         var restParameters = [];
         for (var _a = 0; _a < arguments.length; _a++) {
-            restParameters[_a - 0] = arguments[_a];
+            restParameters[_a] = arguments[_a];
         }
         var _i = 10; // no error
     }

tests/baselines/reference/collisionRestParameterClassMethod.js

@@ -70,7 +70,7 @@ var c3 = (function () {
     c3.prototype.foo = function () {
         var restParameters = [];
         for (var _a = 0; _a < arguments.length; _a++) {
-            restParameters[_a - 0] = arguments[_a];
+            restParameters[_a] = arguments[_a];
         }
         var _i = 10; // no error
     };

tests/baselines/reference/collisionRestParameterFunction.js

@@ -48,7 +48,7 @@ function f1NoError(_i) {
 function f3() {
     var restParameters = [];
     for (var _a = 0; _a < arguments.length; _a++) {
-        restParameters[_a - 0] = arguments[_a];
+        restParameters[_a] = arguments[_a];
     }
     var _i = 10; // no error
 }

tests/baselines/reference/collisionRestParameterFunctionExpressions.js

@@ -39,7 +39,7 @@ function foo() {
     function f3() {
         var restParameters = [];
         for (var _a = 0; _a < arguments.length; _a++) {
-            restParameters[_a - 0] = arguments[_a];
+            restParameters[_a] = arguments[_a];
         }
         var _i = 10; // no error
     }

tests/baselines/reference/collisionRestParameterUnderscoreIUsage.js

@@ -14,7 +14,7 @@ var Foo = (function () {
     function Foo() {
         var args = [];
         for (var _a = 0; _a < arguments.length; _a++) {
-            args[_a - 0] = arguments[_a];
+            args[_a] = arguments[_a];
         }
         console.log(_i); // This should result in error
     }

tests/baselines/reference/constructorWithIncompleteTypeAnnotation.js

@@ -297,7 +297,7 @@ var TypeScriptAllInOne;
         Program.Main = function () {
             var args = [];
             for (var _i = 0; _i < arguments.length; _i++) {
-                args[_i - 0] = arguments[_i];
+                args[_i] = arguments[_i];
             }
             try {
                 var bfs = new BasicFeatures();

tests/baselines/reference/contextuallyTypedIife.js

@@ -57,21 +57,21 @@ let eleven = (o => o.a(11))({ a: function(n) { return n; } });
 (function () {
     var numbers = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        numbers[_i - 0] = arguments[_i];
+        numbers[_i] = arguments[_i];
     }
     return numbers.every(function (n) { return n > 0; });
 })(5, 6, 7);
 (function () {
     var mixed = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        mixed[_i - 0] = arguments[_i];
+        mixed[_i] = arguments[_i];
     }
     return mixed.every(function (n) { return !!n; });
 })(5, 'oops', 'oh no');
 (function () {
     var noNumbers = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        noNumbers[_i - 0] = arguments[_i];
+        noNumbers[_i] = arguments[_i];
     }
     return noNumbers.some(function (n) { return n > 0; });
 })();

tests/baselines/reference/contextuallyTypingRestParameters.js

@@ -11,7 +11,7 @@ var x: (...y: string[]) => void = function (.../*3*/y) {
 var x = function () {
     var y = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        y[_i - 0] = arguments[_i];
+        y[_i] = arguments[_i];
     }
     var t = y;
     var x2 = t; // This should be error

tests/baselines/reference/declFileRestParametersOfFunctionAndFunctionType.js

@@ -14,7 +14,7 @@ var f6 = () => { return [<any>10]; }
 function f1() {
     var args = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        args[_i - 0] = arguments[_i];
+        args[_i] = arguments[_i];
     }
 }
 function f2(x) { }

tests/baselines/reference/declarationEmitDestructuringOptionalBindingParametersInOverloads.js

@@ -13,13 +13,13 @@ function foo2(...rest: any[]) {
 function foo() {
     var rest = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        rest[_i - 0] = arguments[_i];
+        rest[_i] = arguments[_i];
     }
 }
 function foo2() {
     var rest = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        rest[_i - 0] = arguments[_i];
+        rest[_i] = arguments[_i];
     }
 }
 

tests/baselines/reference/defaultExportWithOverloads01.js

@@ -10,7 +10,7 @@ export default function f(...args: any[]) {
 function f() {
     var args = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        args[_i - 0] = arguments[_i];
+        args[_i] = arguments[_i];
     }
 }
 Object.defineProperty(exports, "__esModule", { value: true });

tests/baselines/reference/destructuringParameterDeclaration4.js

@@ -43,31 +43,31 @@ foo1(1, 2, "string", E1.a, E.b);  // Error
 function a0() {
     var x = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        x[_i - 0] = arguments[_i];
+        x[_i] = arguments[_i];
     }
 } // Error, rest parameter must be array type
 function a1() {
     var x = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        x[_i - 0] = arguments[_i];
+        x[_i] = arguments[_i];
     }
 }
 function a2() {
     var a = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        a[_i - 0] = arguments[_i];
+        a[_i] = arguments[_i];
     }
 } // Error, rest parameter must be array type
 function a3() {
     var b = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        b[_i - 0] = arguments[_i];
+        b[_i] = arguments[_i];
     }
 } // Error, can't be optional
 function a4() {
     var b = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        b[_i - 0] = arguments[_i];
+        b[_i] = arguments[_i];
     }
 } // Error, can't have initializer
 function a5(_a) {
@@ -86,7 +86,7 @@ var C = (function () {
     function C() {
         var temp = [];
         for (var _i = 0; _i < arguments.length; _i++) {
-            temp[_i - 0] = arguments[_i];
+            temp[_i] = arguments[_i];
         }
         this.temp = temp;
     } // Error, rest parameter can't have properties
@@ -96,7 +96,7 @@ var C = (function () {
 function foo1() {
     var a = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        a[_i - 0] = arguments[_i];
+        a[_i] = arguments[_i];
     }
 }
 foo1(1, 2, "string", E1.a, E.b); // Error

tests/baselines/reference/destructuringParameterDeclaration6.js

@@ -40,20 +40,20 @@ while (, )
 function a5() {
     var  = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        [_i - 0] = arguments[_i];
+        [_i] = arguments[_i];
     }
 }
 while () { }
 function a6() {
     var public = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        public[_i - 0] = arguments[_i];
+        public[_i] = arguments[_i];
     }
 }
 function a7() {
     var a = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        a[_i - 0] = arguments[_i];
+        a[_i] = arguments[_i];
     }
 }
 a({ "while": 1 });

tests/baselines/reference/detachedCommentAtStartOfLambdaFunction1.js

@@ -19,7 +19,7 @@ var TestFile = (function () {
         return function () {
             var x = [];
             for (var _i = 0; _i < arguments.length; _i++) {
-                x[_i - 0] = arguments[_i];
+                x[_i] = arguments[_i];
             }
             /// <summary>Test summary</summary>
             /// <param name="message" type="String" />

tests/baselines/reference/detachedCommentAtStartOfLambdaFunction2.js

@@ -23,7 +23,7 @@ var TestFile = (function () {
             /// <returns type="Function" />
             var x = [];
             for (var _i = 0; _i < arguments.length; _i++) {
-                x[_i - 0] = arguments[_i];
+                x[_i] = arguments[_i];
             }
             return message + _this.name;
         };

tests/baselines/reference/disallowLineTerminatorBeforeArrow.js

@@ -92,13 +92,13 @@ var f4 = function (x, y) {
 var f5 = function () {
     var rest = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        rest[_i - 0] = arguments[_i];
+        rest[_i] = arguments[_i];
     }
 };
 var f6 = function () {
     var rest = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        rest[_i - 0] = arguments[_i];
+        rest[_i] = arguments[_i];
     }
 };
 var f7 = function (x, y, z) {

tests/baselines/reference/emitDecoratorMetadata_restArgs.js

@@ -32,13 +32,13 @@ var A = (function () {
     function A() {
         var args = [];
         for (var _i = 0; _i < arguments.length; _i++) {
-            args[_i - 0] = arguments[_i];
+            args[_i] = arguments[_i];
         }
     }
     A.prototype.method = function () {
         var args = [];
         for (var _i = 0; _i < arguments.length; _i++) {
-            args[_i - 0] = arguments[_i];
+            args[_i] = arguments[_i];
         }
     };
     return A;
@@ -57,13 +57,13 @@ var B = (function () {
     function B() {
         var args = [];
         for (var _i = 0; _i < arguments.length; _i++) {
-            args[_i - 0] = arguments[_i];
+            args[_i] = arguments[_i];
         }
     }
     B.prototype.method = function () {
         var args = [];
         for (var _i = 0; _i < arguments.length; _i++) {
-            args[_i - 0] = arguments[_i];
+            args[_i] = arguments[_i];
         }
     };
     return B;

tests/baselines/reference/emitRestParametersFunction.js

@@ -6,7 +6,7 @@ function foo(x: number, y: string, ...rest) { }
 function bar() {
     var rest = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        rest[_i - 0] = arguments[_i];
+        rest[_i] = arguments[_i];
     }
 }
 function foo(x, y) {

tests/baselines/reference/emitRestParametersFunctionExpression.js

@@ -9,7 +9,7 @@ var funcExp3 = (function (...rest) { })()
 var funcExp = function () {
     var rest = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        rest[_i - 0] = arguments[_i];
+        rest[_i] = arguments[_i];
     }
 };
 var funcExp1 = function (X) {
@@ -21,12 +21,12 @@ var funcExp1 = function (X) {
 var funcExp2 = function () {
     var rest = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        rest[_i - 0] = arguments[_i];
+        rest[_i] = arguments[_i];
     }
 };
 var funcExp3 = (function () {
     var rest = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        rest[_i - 0] = arguments[_i];
+        rest[_i] = arguments[_i];
     }
 })();

tests/baselines/reference/emitRestParametersFunctionProperty.js

@@ -13,7 +13,7 @@ var obj2 = {
     func: function () {
         var rest = [];
         for (var _i = 0; _i < arguments.length; _i++) {
-            rest[_i - 0] = arguments[_i];
+            rest[_i] = arguments[_i];
         }
     }
 };

tests/baselines/reference/emitRestParametersMethod.js

@@ -24,7 +24,7 @@ var C = (function () {
     C.prototype.bar = function () {
         var rest = [];
         for (var _i = 0; _i < arguments.length; _i++) {
-            rest[_i - 0] = arguments[_i];
+            rest[_i] = arguments[_i];
         }
     };
     C.prototype.foo = function (x) {
@@ -39,13 +39,13 @@ var D = (function () {
     function D() {
         var rest = [];
         for (var _i = 0; _i < arguments.length; _i++) {
-            rest[_i - 0] = arguments[_i];
+            rest[_i] = arguments[_i];
         }
     }
     D.prototype.bar = function () {
         var rest = [];
         for (var _i = 0; _i < arguments.length; _i++) {
-            rest[_i - 0] = arguments[_i];
+            rest[_i] = arguments[_i];
         }
     };
     D.prototype.foo = function (x) {

tests/baselines/reference/emitSkipsThisWithRestParameter.js

@@ -11,7 +11,7 @@ function rebase(fn) {
     return function () {
         var args = [];
         for (var _i = 0; _i < arguments.length; _i++) {
-            args[_i - 0] = arguments[_i];
+            args[_i] = arguments[_i];
         }
         return fn.apply(this, [this].concat(args));
     };

tests/baselines/reference/es6ClassTest2.js

@@ -236,7 +236,7 @@ var SplatMonster = (function () {
     function SplatMonster() {
         var args = [];
         for (var _i = 0; _i < arguments.length; _i++) {
-            args[_i - 0] = arguments[_i];
+            args[_i] = arguments[_i];
         }
     }
     SplatMonster.prototype.roar = function (name) {

tests/baselines/reference/es6modulekindWithES5Target6.js

@@ -17,7 +17,7 @@ export function f1(d) {
 export function f2() {
     var arg = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        arg[_i - 0] = arguments[_i];
+        arg[_i] = arguments[_i];
     }
 }
 export default function f3(d) {

tests/baselines/reference/fatarrowfunctionsErrors.js

@@ -16,7 +16,7 @@ var x4= (...a: any[]) { };
 foo(function () {
     var Far = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        Far[_i - 0] = arguments[_i];
+        Far[_i] = arguments[_i];
     }
     return 0;
 });
@@ -36,6 +36,6 @@ var x3 = function (a) { };
 var x4 = function () {
     var a = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        a[_i - 0] = arguments[_i];
+        a[_i] = arguments[_i];
     }
 };

tests/baselines/reference/fatarrowfunctionsOptionalArgs.js

@@ -159,7 +159,7 @@ foo(
 (function () {
     var arg = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        arg[_i - 0] = arguments[_i];
+        arg[_i] = arguments[_i];
     }
     return 8;
 });
@@ -203,7 +203,7 @@ foo(
 (function () {
     var arg = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        arg[_i - 0] = arguments[_i];
+        arg[_i] = arguments[_i];
     }
     return 28;
 });
@@ -226,7 +226,7 @@ false ? function (arg) {
 false ? function () {
     var arg = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        arg[_i - 0] = arguments[_i];
+        arg[_i] = arguments[_i];
     }
     return 48;
 } : null;
@@ -247,7 +247,7 @@ false ? (function (arg) {
 false ? (function () {
     var arg = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        arg[_i - 0] = arguments[_i];
+        arg[_i] = arguments[_i];
     }
     return 58;
 }) : null;
@@ -268,7 +268,7 @@ false ? null : function (arg) {
 false ? null : function () {
     var arg = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        arg[_i - 0] = arguments[_i];
+        arg[_i] = arguments[_i];
     }
     return 68;
 };
@@ -294,7 +294,7 @@ false ? null : function () {
 (function () {
     var arg = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        arg[_i - 0] = arguments[_i];
+        arg[_i] = arguments[_i];
     }
     return 96;
 }) instanceof Function;
@@ -326,13 +326,13 @@ false ? null : function () {
 (function () {
     var arg = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        arg[_i - 0] = arguments[_i];
+        arg[_i] = arguments[_i];
     }
     return 0;
 }) + '' + (function () {
     var arg = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        arg[_i - 0] = arguments[_i];
+        arg[_i] = arguments[_i];
     }
     return 107;
 });
@@ -354,7 +354,7 @@ false ? null : function () {
 function foo() {
     var arg = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        arg[_i - 0] = arguments[_i];
+        arg[_i] = arguments[_i];
     }
 }
 foo(function (a) { return 110; }, (function (a) { return 111; }), function (a) {
@@ -371,7 +371,7 @@ foo(function (a) { return 110; }, (function (a) { return 111; }), function (a) {
 }, function () {
     var a = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        a[_i - 0] = arguments[_i];
+        a[_i] = arguments[_i];
     }
     return 119;
 }, function (a, b) {

tests/baselines/reference/fatarrowfunctionsOptionalArgsErrors1.js

@@ -12,21 +12,21 @@
 (function () {
     var arg = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        arg[_i - 0] = arguments[_i];
+        arg[_i] = arguments[_i];
     }
     return 102;
 });
 (function () {
     var arg = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        arg[_i - 0] = arguments[_i];
+        arg[_i] = arguments[_i];
     }
     return 103;
 });
 (function () {
     var arg = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        arg[_i - 0] = arguments[_i];
+        arg[_i] = arguments[_i];
     }
     return 104;
 });

tests/baselines/reference/fatarrowfunctionsOptionalArgsErrors3.js

@@ -6,7 +6,7 @@
 (function () {
     var  = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        [_i - 0] = arguments[_i];
+        [_i] = arguments[_i];
     }
     return 105;
 });

tests/baselines/reference/fatarrowfunctionsOptionalArgsErrors4.js

@@ -56,7 +56,7 @@ foo(function (a) { return 110; }, (function (a) { return 111; }), function (a) {
 }, function () {
     var a = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        a[_i - 0] = arguments[_i];
+        a[_i] = arguments[_i];
     }
     return 119;
 }, function (a, b) {

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

@@ -1,7 +1,9 @@
+tests/cases/conformance/statements/for-inStatements/for-inStatements.ts(33,18): error TS2403: Subsequent variable declarations must have the same type.  Variable 'x' must be of type 'string', but here has type 'keyof this'.
+tests/cases/conformance/statements/for-inStatements/for-inStatements.ts(50,18): error TS2403: Subsequent variable declarations must have the same type.  Variable 'x' must be of type 'string', but here has type 'keyof this'.
 tests/cases/conformance/statements/for-inStatements/for-inStatements.ts(79,15): error TS2407: The right-hand side of a 'for...in' statement must be of type 'any', an object type or a type parameter.
 
 
-==== tests/cases/conformance/statements/for-inStatements/for-inStatements.ts (1 errors) ====
+==== tests/cases/conformance/statements/for-inStatements/for-inStatements.ts (3 errors) ====
     var aString: string;
     for (aString in {}) { }
     
@@ -35,6 +37,8 @@ tests/cases/conformance/statements/for-inStatements/for-inStatements.ts(79,15):
             for (var x in this.biz()) { }
             for (var x in this.biz) { }
             for (var x in this) { }
+                     ~
+!!! error TS2403: Subsequent variable declarations must have the same type.  Variable 'x' must be of type 'string', but here has type 'keyof this'.
             return null;
         }
     
@@ -52,6 +56,8 @@ tests/cases/conformance/statements/for-inStatements/for-inStatements.ts(79,15):
             for (var x in this.biz()) { }
             for (var x in this.biz) { }
             for (var x in this) { }
+                     ~
+!!! error TS2403: Subsequent variable declarations must have the same type.  Variable 'x' must be of type 'string', but here has type 'keyof this'.
     
             for (var x in super.biz) { }
             for (var x in super.biz()) { }

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

@@ -9,13 +9,15 @@ tests/cases/conformance/statements/for-inStatements/for-inStatementsInvalid.ts(1
 tests/cases/conformance/statements/for-inStatements/for-inStatementsInvalid.ts(20,15): error TS2407: The right-hand side of a 'for...in' statement must be of type 'any', an object type or a type parameter.
 tests/cases/conformance/statements/for-inStatements/for-inStatementsInvalid.ts(22,15): error TS2407: The right-hand side of a 'for...in' statement must be of type 'any', an object type or a type parameter.
 tests/cases/conformance/statements/for-inStatements/for-inStatementsInvalid.ts(29,23): error TS2407: The right-hand side of a 'for...in' statement must be of type 'any', an object type or a type parameter.
+tests/cases/conformance/statements/for-inStatements/for-inStatementsInvalid.ts(31,18): error TS2403: Subsequent variable declarations must have the same type.  Variable 'x' must be of type 'string', but here has type 'keyof this'.
 tests/cases/conformance/statements/for-inStatements/for-inStatementsInvalid.ts(38,23): error TS2407: The right-hand side of a 'for...in' statement must be of type 'any', an object type or a type parameter.
 tests/cases/conformance/statements/for-inStatements/for-inStatementsInvalid.ts(46,23): error TS2407: The right-hand side of a 'for...in' statement must be of type 'any', an object type or a type parameter.
+tests/cases/conformance/statements/for-inStatements/for-inStatementsInvalid.ts(48,18): error TS2403: Subsequent variable declarations must have the same type.  Variable 'x' must be of type 'string', but here has type 'keyof this'.
 tests/cases/conformance/statements/for-inStatements/for-inStatementsInvalid.ts(51,23): error TS2407: The right-hand side of a 'for...in' statement must be of type 'any', an object type or a type parameter.
 tests/cases/conformance/statements/for-inStatements/for-inStatementsInvalid.ts(62,15): error TS2407: The right-hand side of a 'for...in' statement must be of type 'any', an object type or a type parameter.
 
 
-==== tests/cases/conformance/statements/for-inStatements/for-inStatementsInvalid.ts (15 errors) ====
+==== tests/cases/conformance/statements/for-inStatements/for-inStatementsInvalid.ts (17 errors) ====
     var aNumber: number;
     for (aNumber in {}) { }
          ~~~~~~~
@@ -69,6 +71,8 @@ tests/cases/conformance/statements/for-inStatements/for-inStatementsInvalid.ts(6
 !!! error TS2407: The right-hand side of a 'for...in' statement must be of type 'any', an object type or a type parameter.
             for (var x in this.biz) { }
             for (var x in this) { }
+                     ~
+!!! error TS2403: Subsequent variable declarations must have the same type.  Variable 'x' must be of type 'string', but here has type 'keyof this'.
             return null;
         }
     
@@ -90,6 +94,8 @@ tests/cases/conformance/statements/for-inStatements/for-inStatementsInvalid.ts(6
 !!! error TS2407: The right-hand side of a 'for...in' statement must be of type 'any', an object type or a type parameter.
             for (var x in this.biz) { }
             for (var x in this) { }
+                     ~
+!!! error TS2403: Subsequent variable declarations must have the same type.  Variable 'x' must be of type 'string', but here has type 'keyof this'.
     
             for (var x in super.biz) { }
             for (var x in super.biz()) { }

tests/baselines/reference/forInStatement3.types

@@ -8,7 +8,7 @@ function F<T>() {
 >T : T
 
   for (var a in expr) {
->a : string
+>a : keyof T
 >expr : T
   }
 }

tests/baselines/reference/functionCall10.js

@@ -10,7 +10,7 @@ foo(1, 'bar');
 function foo() {
     var a = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        a[_i - 0] = arguments[_i];
+        a[_i] = arguments[_i];
     }
 }
 ;

tests/baselines/reference/functionOverloadsRecursiveGenericReturnType.js

@@ -28,7 +28,7 @@ var A = (function () {
 function Choice() {
     var v_args = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        v_args[_i - 0] = arguments[_i];
+        v_args[_i] = arguments[_i];
     }
     return new A();
 }

tests/baselines/reference/genericRestArgs.js

@@ -16,7 +16,7 @@ var a2Gc = makeArrayG<any[]>(1, ""); // error
 function makeArrayG() {
     var items = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        items[_i - 0] = arguments[_i];
+        items[_i] = arguments[_i];
     }
     return items;
 }

tests/baselines/reference/implicitAnyDeclareFunctionWithoutFormalType.js

@@ -22,7 +22,7 @@ function func2(a, b, c) { }
 function func3() {
     var args = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        args[_i - 0] = arguments[_i];
+        args[_i] = arguments[_i];
     }
 }
 ; // error at "args" 

tests/baselines/reference/implicitAnyInCatch.types

@@ -22,7 +22,7 @@ class C {
 >temp : () => void
 
         for (var x in this) {
->x : string
+>x : keyof this
 >this : this
         }
     }

tests/baselines/reference/inOperatorWithGeneric.types

@@ -9,7 +9,7 @@ class C<T> {
 >T : T
 
         for (var p in x) {
->p : string
+>p : keyof T
 >x : T
         }
     }

tests/baselines/reference/inheritedConstructorWithRestParams.js

@@ -24,7 +24,7 @@ var Base = (function () {
     function Base() {
         var a = [];
         for (var _i = 0; _i < arguments.length; _i++) {
-            a[_i - 0] = arguments[_i];
+            a[_i] = arguments[_i];
         }
     }
     return Base;

tests/baselines/reference/keyofAndIndexedAccess.js

@@ -95,22 +95,18 @@ function f10(shape: Shape) {
 
 function f11(a: Shape[]) {
     let len = getProperty(a, "length");  // number
-    let shape = getProperty(a, 1000);    // Shape
-    setProperty(a, 1000, getProperty(a, 1001));
+    setProperty(a, "length", len);
 }
 
 function f12(t: [Shape, boolean]) {
     let len = getProperty(t, "length");
-    let s1 = getProperty(t, 0);    // Shape
     let s2 = getProperty(t, "0");  // Shape
-    let b1 = getProperty(t, 1);    // boolean
     let b2 = getProperty(t, "1");  // boolean
-    let x1 = getProperty(t, 2);    // Shape | boolean
 }
 
 function f13(foo: any, bar: any) {
     let x = getProperty(foo, "x");  // any
-    let y = getProperty(foo, 100);  // any
+    let y = getProperty(foo, "100");  // any
     let z = getProperty(foo, bar);  // any
 }
 
@@ -181,6 +177,46 @@ function f40(c: C) {
     let z: Z = c["z"];
 }
 
+function f50<T>(k: keyof T, s: string) {
+    const x1 = s as keyof T;
+    const x2 = k as string;
+}
+
+function f51<T, K extends keyof T>(k: K, s: string) {
+    const x1 = s as keyof T;
+    const x2 = k as string;
+}
+
+function f52<T>(obj: { [x: string]: boolean }, k: keyof T, s: string, n: number) {
+    const x1 = obj[s];
+    const x2 = obj[n];
+    const x3 = obj[k];
+}
+
+function f53<T, K extends keyof T>(obj: { [x: string]: boolean }, k: K, s: string, n: number) {
+    const x1 = obj[s];
+    const x2 = obj[n];
+    const x3 = obj[k];
+}
+
+function f54<T>(obj: T, key: keyof T) {
+    for (let s in obj[key]) {
+    }
+    const b = "foo" in obj[key];
+}
+
+function f55<T, K extends keyof T>(obj: T, key: K) {
+    for (let s in obj[key]) {
+    }
+    const b = "foo" in obj[key];
+}
+
+function f60<T>(source: T, target: T) {
+    for (let k in source) {
+        target[k] = source[k];
+    }
+}
+
 // Repros from #12011
 
 class Base {
@@ -257,20 +293,16 @@ function f10(shape) {
 }
 function f11(a) {
     var len = getProperty(a, "length"); // number
-    var shape = getProperty(a, 1000); // Shape
-    setProperty(a, 1000, getProperty(a, 1001));
+    setProperty(a, "length", len);
 }
 function f12(t) {
     var len = getProperty(t, "length");
-    var s1 = getProperty(t, 0); // Shape
     var s2 = getProperty(t, "0"); // Shape
-    var b1 = getProperty(t, 1); // boolean
     var b2 = getProperty(t, "1"); // boolean
-    var x1 = getProperty(t, 2); // Shape | boolean
 }
 function f13(foo, bar) {
     var x = getProperty(foo, "x"); // any
-    var y = getProperty(foo, 100); // any
+    var y = getProperty(foo, "100"); // any
     var z = getProperty(foo, bar); // any
 }
 var Component = (function () {
@@ -329,6 +361,39 @@ function f40(c) {
     var y = c["y"];
     var z = c["z"];
 }
+function f50(k, s) {
+    var x1 = s;
+    var x2 = k;
+}
+function f51(k, s) {
+    var x1 = s;
+    var x2 = k;
+}
+function f52(obj, k, s, n) {
+    var x1 = obj[s];
+    var x2 = obj[n];
+    var x3 = obj[k];
+}
+function f53(obj, k, s, n) {
+    var x1 = obj[s];
+    var x2 = obj[n];
+    var x3 = obj[k];
+}
+function f54(obj, key) {
+    for (var s in obj[key]) {
+    }
+    var b = "foo" in obj[key];
+}
+function f55(obj, key) {
+    for (var s in obj[key]) {
+    }
+    var b = "foo" in obj[key];
+}
+function f60(source, target) {
+    for (var k in source) {
+        target[k] = source[k];
+    }
+}
 // Repros from #12011
 var Base = (function () {
     function Base() {
@@ -454,6 +519,17 @@ declare class C {
     private z;
 }
 declare function f40(c: C): void;
+declare function f50<T>(k: keyof T, s: string): void;
+declare function f51<T, K extends keyof T>(k: K, s: string): void;
+declare function f52<T>(obj: {
+    [x: string]: boolean;
+}, k: keyof T, s: string, n: number): void;
+declare function f53<T, K extends keyof T>(obj: {
+    [x: string]: boolean;
+}, k: K, s: string, n: number): void;
+declare function f54<T>(obj: T, key: keyof T): void;
+declare function f55<T, K extends keyof T>(obj: T, key: K): void;
+declare function f60<T>(source: T, target: T): void;
 declare class Base {
     get<K extends keyof this>(prop: K): this[K];
     set<K extends keyof this>(prop: K, value: this[K]): void;

tests/baselines/reference/keyofAndIndexedAccess.symbols

@@ -299,411 +299,540 @@ function f11(a: Shape[]) {
 >getProperty : Symbol(getProperty, Decl(keyofAndIndexedAccess.ts, 75, 26))
 >a : Symbol(a, Decl(keyofAndIndexedAccess.ts, 94, 13))
 
-    let shape = getProperty(a, 1000);    // Shape
->shape : Symbol(shape, Decl(keyofAndIndexedAccess.ts, 96, 7))
->getProperty : Symbol(getProperty, Decl(keyofAndIndexedAccess.ts, 75, 26))
->a : Symbol(a, Decl(keyofAndIndexedAccess.ts, 94, 13))
-
-    setProperty(a, 1000, getProperty(a, 1001));
+    setProperty(a, "length", len);
 >setProperty : Symbol(setProperty, Decl(keyofAndIndexedAccess.ts, 79, 1))
 >a : Symbol(a, Decl(keyofAndIndexedAccess.ts, 94, 13))
->getProperty : Symbol(getProperty, Decl(keyofAndIndexedAccess.ts, 75, 26))
->a : Symbol(a, Decl(keyofAndIndexedAccess.ts, 94, 13))
+>len : Symbol(len, Decl(keyofAndIndexedAccess.ts, 95, 7))
 }
 
 function f12(t: [Shape, boolean]) {
->f12 : Symbol(f12, Decl(keyofAndIndexedAccess.ts, 98, 1))
->t : Symbol(t, Decl(keyofAndIndexedAccess.ts, 100, 13))
+>f12 : Symbol(f12, Decl(keyofAndIndexedAccess.ts, 97, 1))
+>t : Symbol(t, Decl(keyofAndIndexedAccess.ts, 99, 13))
 >Shape : Symbol(Shape, Decl(keyofAndIndexedAccess.ts, 0, 0))
 
     let len = getProperty(t, "length");
->len : Symbol(len, Decl(keyofAndIndexedAccess.ts, 101, 7))
+>len : Symbol(len, Decl(keyofAndIndexedAccess.ts, 100, 7))
 >getProperty : Symbol(getProperty, Decl(keyofAndIndexedAccess.ts, 75, 26))
->t : Symbol(t, Decl(keyofAndIndexedAccess.ts, 100, 13))
-
-    let s1 = getProperty(t, 0);    // Shape
->s1 : Symbol(s1, Decl(keyofAndIndexedAccess.ts, 102, 7))
->getProperty : Symbol(getProperty, Decl(keyofAndIndexedAccess.ts, 75, 26))
->t : Symbol(t, Decl(keyofAndIndexedAccess.ts, 100, 13))
+>t : Symbol(t, Decl(keyofAndIndexedAccess.ts, 99, 13))
 
     let s2 = getProperty(t, "0");  // Shape
->s2 : Symbol(s2, Decl(keyofAndIndexedAccess.ts, 103, 7))
+>s2 : Symbol(s2, Decl(keyofAndIndexedAccess.ts, 101, 7))
 >getProperty : Symbol(getProperty, Decl(keyofAndIndexedAccess.ts, 75, 26))
->t : Symbol(t, Decl(keyofAndIndexedAccess.ts, 100, 13))
-
-    let b1 = getProperty(t, 1);    // boolean
->b1 : Symbol(b1, Decl(keyofAndIndexedAccess.ts, 104, 7))
->getProperty : Symbol(getProperty, Decl(keyofAndIndexedAccess.ts, 75, 26))
->t : Symbol(t, Decl(keyofAndIndexedAccess.ts, 100, 13))
+>t : Symbol(t, Decl(keyofAndIndexedAccess.ts, 99, 13))
 
     let b2 = getProperty(t, "1");  // boolean
->b2 : Symbol(b2, Decl(keyofAndIndexedAccess.ts, 105, 7))
+>b2 : Symbol(b2, Decl(keyofAndIndexedAccess.ts, 102, 7))
 >getProperty : Symbol(getProperty, Decl(keyofAndIndexedAccess.ts, 75, 26))
->t : Symbol(t, Decl(keyofAndIndexedAccess.ts, 100, 13))
-
-    let x1 = getProperty(t, 2);    // Shape | boolean
->x1 : Symbol(x1, Decl(keyofAndIndexedAccess.ts, 106, 7))
->getProperty : Symbol(getProperty, Decl(keyofAndIndexedAccess.ts, 75, 26))
->t : Symbol(t, Decl(keyofAndIndexedAccess.ts, 100, 13))
+>t : Symbol(t, Decl(keyofAndIndexedAccess.ts, 99, 13))
 }
 
 function f13(foo: any, bar: any) {
->f13 : Symbol(f13, Decl(keyofAndIndexedAccess.ts, 107, 1))
->foo : Symbol(foo, Decl(keyofAndIndexedAccess.ts, 109, 13))
->bar : Symbol(bar, Decl(keyofAndIndexedAccess.ts, 109, 22))
+>f13 : Symbol(f13, Decl(keyofAndIndexedAccess.ts, 103, 1))
+>foo : Symbol(foo, Decl(keyofAndIndexedAccess.ts, 105, 13))
+>bar : Symbol(bar, Decl(keyofAndIndexedAccess.ts, 105, 22))
 
     let x = getProperty(foo, "x");  // any
->x : Symbol(x, Decl(keyofAndIndexedAccess.ts, 110, 7))
+>x : Symbol(x, Decl(keyofAndIndexedAccess.ts, 106, 7))
 >getProperty : Symbol(getProperty, Decl(keyofAndIndexedAccess.ts, 75, 26))
->foo : Symbol(foo, Decl(keyofAndIndexedAccess.ts, 109, 13))
+>foo : Symbol(foo, Decl(keyofAndIndexedAccess.ts, 105, 13))
 
-    let y = getProperty(foo, 100);  // any
->y : Symbol(y, Decl(keyofAndIndexedAccess.ts, 111, 7))
+    let y = getProperty(foo, "100");  // any
+>y : Symbol(y, Decl(keyofAndIndexedAccess.ts, 107, 7))
 >getProperty : Symbol(getProperty, Decl(keyofAndIndexedAccess.ts, 75, 26))
->foo : Symbol(foo, Decl(keyofAndIndexedAccess.ts, 109, 13))
+>foo : Symbol(foo, Decl(keyofAndIndexedAccess.ts, 105, 13))
 
     let z = getProperty(foo, bar);  // any
->z : Symbol(z, Decl(keyofAndIndexedAccess.ts, 112, 7))
+>z : Symbol(z, Decl(keyofAndIndexedAccess.ts, 108, 7))
 >getProperty : Symbol(getProperty, Decl(keyofAndIndexedAccess.ts, 75, 26))
->foo : Symbol(foo, Decl(keyofAndIndexedAccess.ts, 109, 13))
->bar : Symbol(bar, Decl(keyofAndIndexedAccess.ts, 109, 22))
+>foo : Symbol(foo, Decl(keyofAndIndexedAccess.ts, 105, 13))
+>bar : Symbol(bar, Decl(keyofAndIndexedAccess.ts, 105, 22))
 }
 
 class Component<PropType> {
->Component : Symbol(Component, Decl(keyofAndIndexedAccess.ts, 113, 1))
->PropType : Symbol(PropType, Decl(keyofAndIndexedAccess.ts, 115, 16))
+>Component : Symbol(Component, Decl(keyofAndIndexedAccess.ts, 109, 1))
+>PropType : Symbol(PropType, Decl(keyofAndIndexedAccess.ts, 111, 16))
 
     props: PropType;
->props : Symbol(Component.props, Decl(keyofAndIndexedAccess.ts, 115, 27))
->PropType : Symbol(PropType, Decl(keyofAndIndexedAccess.ts, 115, 16))
+>props : Symbol(Component.props, Decl(keyofAndIndexedAccess.ts, 111, 27))
+>PropType : Symbol(PropType, Decl(keyofAndIndexedAccess.ts, 111, 16))
 
     getProperty<K extends keyof PropType>(key: K) {
->getProperty : Symbol(Component.getProperty, Decl(keyofAndIndexedAccess.ts, 116, 20))
->K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 117, 16))
->PropType : Symbol(PropType, Decl(keyofAndIndexedAccess.ts, 115, 16))
->key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 117, 42))
->K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 117, 16))
+>getProperty : Symbol(Component.getProperty, Decl(keyofAndIndexedAccess.ts, 112, 20))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 113, 16))
+>PropType : Symbol(PropType, Decl(keyofAndIndexedAccess.ts, 111, 16))
+>key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 113, 42))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 113, 16))
 
         return this.props[key];
->this.props : Symbol(Component.props, Decl(keyofAndIndexedAccess.ts, 115, 27))
->this : Symbol(Component, Decl(keyofAndIndexedAccess.ts, 113, 1))
->props : Symbol(Component.props, Decl(keyofAndIndexedAccess.ts, 115, 27))
->key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 117, 42))
+>this.props : Symbol(Component.props, Decl(keyofAndIndexedAccess.ts, 111, 27))
+>this : Symbol(Component, Decl(keyofAndIndexedAccess.ts, 109, 1))
+>props : Symbol(Component.props, Decl(keyofAndIndexedAccess.ts, 111, 27))
+>key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 113, 42))
     }
     setProperty<K extends keyof PropType>(key: K, value: PropType[K]) {
->setProperty : Symbol(Component.setProperty, Decl(keyofAndIndexedAccess.ts, 119, 5))
->K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 120, 16))
->PropType : Symbol(PropType, Decl(keyofAndIndexedAccess.ts, 115, 16))
->key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 120, 42))
->K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 120, 16))
->value : Symbol(value, Decl(keyofAndIndexedAccess.ts, 120, 49))
->PropType : Symbol(PropType, Decl(keyofAndIndexedAccess.ts, 115, 16))
->K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 120, 16))
+>setProperty : Symbol(Component.setProperty, Decl(keyofAndIndexedAccess.ts, 115, 5))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 116, 16))
+>PropType : Symbol(PropType, Decl(keyofAndIndexedAccess.ts, 111, 16))
+>key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 116, 42))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 116, 16))
+>value : Symbol(value, Decl(keyofAndIndexedAccess.ts, 116, 49))
+>PropType : Symbol(PropType, Decl(keyofAndIndexedAccess.ts, 111, 16))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 116, 16))
 
         this.props[key] = value;
->this.props : Symbol(Component.props, Decl(keyofAndIndexedAccess.ts, 115, 27))
->this : Symbol(Component, Decl(keyofAndIndexedAccess.ts, 113, 1))
->props : Symbol(Component.props, Decl(keyofAndIndexedAccess.ts, 115, 27))
->key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 120, 42))
->value : Symbol(value, Decl(keyofAndIndexedAccess.ts, 120, 49))
+>this.props : Symbol(Component.props, Decl(keyofAndIndexedAccess.ts, 111, 27))
+>this : Symbol(Component, Decl(keyofAndIndexedAccess.ts, 109, 1))
+>props : Symbol(Component.props, Decl(keyofAndIndexedAccess.ts, 111, 27))
+>key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 116, 42))
+>value : Symbol(value, Decl(keyofAndIndexedAccess.ts, 116, 49))
     }
 }
 
 function f20(component: Component<Shape>) {
->f20 : Symbol(f20, Decl(keyofAndIndexedAccess.ts, 123, 1))
->component : Symbol(component, Decl(keyofAndIndexedAccess.ts, 125, 13))
->Component : Symbol(Component, Decl(keyofAndIndexedAccess.ts, 113, 1))
+>f20 : Symbol(f20, Decl(keyofAndIndexedAccess.ts, 119, 1))
+>component : Symbol(component, Decl(keyofAndIndexedAccess.ts, 121, 13))
+>Component : Symbol(Component, Decl(keyofAndIndexedAccess.ts, 109, 1))
 >Shape : Symbol(Shape, Decl(keyofAndIndexedAccess.ts, 0, 0))
 
     let name = component.getProperty("name");  // string
->name : Symbol(name, Decl(keyofAndIndexedAccess.ts, 126, 7))
->component.getProperty : Symbol(Component.getProperty, Decl(keyofAndIndexedAccess.ts, 116, 20))
->component : Symbol(component, Decl(keyofAndIndexedAccess.ts, 125, 13))
->getProperty : Symbol(Component.getProperty, Decl(keyofAndIndexedAccess.ts, 116, 20))
+>name : Symbol(name, Decl(keyofAndIndexedAccess.ts, 122, 7))
+>component.getProperty : Symbol(Component.getProperty, Decl(keyofAndIndexedAccess.ts, 112, 20))
+>component : Symbol(component, Decl(keyofAndIndexedAccess.ts, 121, 13))
+>getProperty : Symbol(Component.getProperty, Decl(keyofAndIndexedAccess.ts, 112, 20))
 
     let widthOrHeight = component.getProperty(cond ? "width" : "height");  // number
->widthOrHeight : Symbol(widthOrHeight, Decl(keyofAndIndexedAccess.ts, 127, 7))
->component.getProperty : Symbol(Component.getProperty, Decl(keyofAndIndexedAccess.ts, 116, 20))
->component : Symbol(component, Decl(keyofAndIndexedAccess.ts, 125, 13))
->getProperty : Symbol(Component.getProperty, Decl(keyofAndIndexedAccess.ts, 116, 20))
+>widthOrHeight : Symbol(widthOrHeight, Decl(keyofAndIndexedAccess.ts, 123, 7))
+>component.getProperty : Symbol(Component.getProperty, Decl(keyofAndIndexedAccess.ts, 112, 20))
+>component : Symbol(component, Decl(keyofAndIndexedAccess.ts, 121, 13))
+>getProperty : Symbol(Component.getProperty, Decl(keyofAndIndexedAccess.ts, 112, 20))
 >cond : Symbol(cond, Decl(keyofAndIndexedAccess.ts, 75, 11))
 
     let nameOrVisible = component.getProperty(cond ? "name" : "visible");  // string | boolean
->nameOrVisible : Symbol(nameOrVisible, Decl(keyofAndIndexedAccess.ts, 128, 7))
->component.getProperty : Symbol(Component.getProperty, Decl(keyofAndIndexedAccess.ts, 116, 20))
->component : Symbol(component, Decl(keyofAndIndexedAccess.ts, 125, 13))
->getProperty : Symbol(Component.getProperty, Decl(keyofAndIndexedAccess.ts, 116, 20))
+>nameOrVisible : Symbol(nameOrVisible, Decl(keyofAndIndexedAccess.ts, 124, 7))
+>component.getProperty : Symbol(Component.getProperty, Decl(keyofAndIndexedAccess.ts, 112, 20))
+>component : Symbol(component, Decl(keyofAndIndexedAccess.ts, 121, 13))
+>getProperty : Symbol(Component.getProperty, Decl(keyofAndIndexedAccess.ts, 112, 20))
 >cond : Symbol(cond, Decl(keyofAndIndexedAccess.ts, 75, 11))
 
     component.setProperty("name", "rectangle");
->component.setProperty : Symbol(Component.setProperty, Decl(keyofAndIndexedAccess.ts, 119, 5))
->component : Symbol(component, Decl(keyofAndIndexedAccess.ts, 125, 13))
->setProperty : Symbol(Component.setProperty, Decl(keyofAndIndexedAccess.ts, 119, 5))
+>component.setProperty : Symbol(Component.setProperty, Decl(keyofAndIndexedAccess.ts, 115, 5))
+>component : Symbol(component, Decl(keyofAndIndexedAccess.ts, 121, 13))
+>setProperty : Symbol(Component.setProperty, Decl(keyofAndIndexedAccess.ts, 115, 5))
 
     component.setProperty(cond ? "width" : "height", 10)
->component.setProperty : Symbol(Component.setProperty, Decl(keyofAndIndexedAccess.ts, 119, 5))
->component : Symbol(component, Decl(keyofAndIndexedAccess.ts, 125, 13))
->setProperty : Symbol(Component.setProperty, Decl(keyofAndIndexedAccess.ts, 119, 5))
+>component.setProperty : Symbol(Component.setProperty, Decl(keyofAndIndexedAccess.ts, 115, 5))
+>component : Symbol(component, Decl(keyofAndIndexedAccess.ts, 121, 13))
+>setProperty : Symbol(Component.setProperty, Decl(keyofAndIndexedAccess.ts, 115, 5))
 >cond : Symbol(cond, Decl(keyofAndIndexedAccess.ts, 75, 11))
 
     component.setProperty(cond ? "name" : "visible", true);  // Technically not safe
->component.setProperty : Symbol(Component.setProperty, Decl(keyofAndIndexedAccess.ts, 119, 5))
->component : Symbol(component, Decl(keyofAndIndexedAccess.ts, 125, 13))
->setProperty : Symbol(Component.setProperty, Decl(keyofAndIndexedAccess.ts, 119, 5))
+>component.setProperty : Symbol(Component.setProperty, Decl(keyofAndIndexedAccess.ts, 115, 5))
+>component : Symbol(component, Decl(keyofAndIndexedAccess.ts, 121, 13))
+>setProperty : Symbol(Component.setProperty, Decl(keyofAndIndexedAccess.ts, 115, 5))
 >cond : Symbol(cond, Decl(keyofAndIndexedAccess.ts, 75, 11))
 }
 
 function pluck<T, K extends keyof T>(array: T[], key: K) {
->pluck : Symbol(pluck, Decl(keyofAndIndexedAccess.ts, 132, 1))
->T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 134, 15))
->K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 134, 17))
->T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 134, 15))
->array : Symbol(array, Decl(keyofAndIndexedAccess.ts, 134, 37))
->T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 134, 15))
->key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 134, 48))
->K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 134, 17))
+>pluck : Symbol(pluck, Decl(keyofAndIndexedAccess.ts, 128, 1))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 130, 15))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 130, 17))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 130, 15))
+>array : Symbol(array, Decl(keyofAndIndexedAccess.ts, 130, 37))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 130, 15))
+>key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 130, 48))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 130, 17))
 
     return array.map(x => x[key]);
 >array.map : Symbol(Array.map, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --))
->array : Symbol(array, Decl(keyofAndIndexedAccess.ts, 134, 37))
+>array : Symbol(array, Decl(keyofAndIndexedAccess.ts, 130, 37))
 >map : Symbol(Array.map, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --))
->x : Symbol(x, Decl(keyofAndIndexedAccess.ts, 135, 21))
->x : Symbol(x, Decl(keyofAndIndexedAccess.ts, 135, 21))
->key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 134, 48))
+>x : Symbol(x, Decl(keyofAndIndexedAccess.ts, 131, 21))
+>x : Symbol(x, Decl(keyofAndIndexedAccess.ts, 131, 21))
+>key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 130, 48))
 }
 
 function f30(shapes: Shape[]) {
->f30 : Symbol(f30, Decl(keyofAndIndexedAccess.ts, 136, 1))
->shapes : Symbol(shapes, Decl(keyofAndIndexedAccess.ts, 138, 13))
+>f30 : Symbol(f30, Decl(keyofAndIndexedAccess.ts, 132, 1))
+>shapes : Symbol(shapes, Decl(keyofAndIndexedAccess.ts, 134, 13))
 >Shape : Symbol(Shape, Decl(keyofAndIndexedAccess.ts, 0, 0))
 
     let names = pluck(shapes, "name");    // string[]
->names : Symbol(names, Decl(keyofAndIndexedAccess.ts, 139, 7))
->pluck : Symbol(pluck, Decl(keyofAndIndexedAccess.ts, 132, 1))
->shapes : Symbol(shapes, Decl(keyofAndIndexedAccess.ts, 138, 13))
+>names : Symbol(names, Decl(keyofAndIndexedAccess.ts, 135, 7))
+>pluck : Symbol(pluck, Decl(keyofAndIndexedAccess.ts, 128, 1))
+>shapes : Symbol(shapes, Decl(keyofAndIndexedAccess.ts, 134, 13))
 
     let widths = pluck(shapes, "width");  // number[]
->widths : Symbol(widths, Decl(keyofAndIndexedAccess.ts, 140, 7))
->pluck : Symbol(pluck, Decl(keyofAndIndexedAccess.ts, 132, 1))
->shapes : Symbol(shapes, Decl(keyofAndIndexedAccess.ts, 138, 13))
+>widths : Symbol(widths, Decl(keyofAndIndexedAccess.ts, 136, 7))
+>pluck : Symbol(pluck, Decl(keyofAndIndexedAccess.ts, 128, 1))
+>shapes : Symbol(shapes, Decl(keyofAndIndexedAccess.ts, 134, 13))
 
     let nameOrVisibles = pluck(shapes, cond ? "name" : "visible");  // (string | boolean)[]
->nameOrVisibles : Symbol(nameOrVisibles, Decl(keyofAndIndexedAccess.ts, 141, 7))
->pluck : Symbol(pluck, Decl(keyofAndIndexedAccess.ts, 132, 1))
->shapes : Symbol(shapes, Decl(keyofAndIndexedAccess.ts, 138, 13))
+>nameOrVisibles : Symbol(nameOrVisibles, Decl(keyofAndIndexedAccess.ts, 137, 7))
+>pluck : Symbol(pluck, Decl(keyofAndIndexedAccess.ts, 128, 1))
+>shapes : Symbol(shapes, Decl(keyofAndIndexedAccess.ts, 134, 13))
 >cond : Symbol(cond, Decl(keyofAndIndexedAccess.ts, 75, 11))
 }
 
 function f31<K extends keyof Shape>(key: K) {
->f31 : Symbol(f31, Decl(keyofAndIndexedAccess.ts, 142, 1))
->K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 144, 13))
+>f31 : Symbol(f31, Decl(keyofAndIndexedAccess.ts, 138, 1))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 140, 13))
 >Shape : Symbol(Shape, Decl(keyofAndIndexedAccess.ts, 0, 0))
->key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 144, 36))
->K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 144, 13))
+>key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 140, 36))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 140, 13))
 
     const shape: Shape = { name: "foo", width: 5, height: 10, visible: true };
->shape : Symbol(shape, Decl(keyofAndIndexedAccess.ts, 145, 9))
+>shape : Symbol(shape, Decl(keyofAndIndexedAccess.ts, 141, 9))
 >Shape : Symbol(Shape, Decl(keyofAndIndexedAccess.ts, 0, 0))
->name : Symbol(name, Decl(keyofAndIndexedAccess.ts, 145, 26))
->width : Symbol(width, Decl(keyofAndIndexedAccess.ts, 145, 39))
->height : Symbol(height, Decl(keyofAndIndexedAccess.ts, 145, 49))
->visible : Symbol(visible, Decl(keyofAndIndexedAccess.ts, 145, 61))
+>name : Symbol(name, Decl(keyofAndIndexedAccess.ts, 141, 26))
+>width : Symbol(width, Decl(keyofAndIndexedAccess.ts, 141, 39))
+>height : Symbol(height, Decl(keyofAndIndexedAccess.ts, 141, 49))
+>visible : Symbol(visible, Decl(keyofAndIndexedAccess.ts, 141, 61))
 
     return shape[key];  // Shape[K]
->shape : Symbol(shape, Decl(keyofAndIndexedAccess.ts, 145, 9))
->key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 144, 36))
+>shape : Symbol(shape, Decl(keyofAndIndexedAccess.ts, 141, 9))
+>key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 140, 36))
 }
 
 function f32<K extends "width" | "height">(key: K) {
->f32 : Symbol(f32, Decl(keyofAndIndexedAccess.ts, 147, 1))
->K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 149, 13))
->key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 149, 43))
->K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 149, 13))
+>f32 : Symbol(f32, Decl(keyofAndIndexedAccess.ts, 143, 1))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 145, 13))
+>key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 145, 43))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 145, 13))
 
     const shape: Shape = { name: "foo", width: 5, height: 10, visible: true };
->shape : Symbol(shape, Decl(keyofAndIndexedAccess.ts, 150, 9))
+>shape : Symbol(shape, Decl(keyofAndIndexedAccess.ts, 146, 9))
 >Shape : Symbol(Shape, Decl(keyofAndIndexedAccess.ts, 0, 0))
->name : Symbol(name, Decl(keyofAndIndexedAccess.ts, 150, 26))
->width : Symbol(width, Decl(keyofAndIndexedAccess.ts, 150, 39))
->height : Symbol(height, Decl(keyofAndIndexedAccess.ts, 150, 49))
->visible : Symbol(visible, Decl(keyofAndIndexedAccess.ts, 150, 61))
+>name : Symbol(name, Decl(keyofAndIndexedAccess.ts, 146, 26))
+>width : Symbol(width, Decl(keyofAndIndexedAccess.ts, 146, 39))
+>height : Symbol(height, Decl(keyofAndIndexedAccess.ts, 146, 49))
+>visible : Symbol(visible, Decl(keyofAndIndexedAccess.ts, 146, 61))
 
     return shape[key];  // Shape[K]
->shape : Symbol(shape, Decl(keyofAndIndexedAccess.ts, 150, 9))
->key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 149, 43))
+>shape : Symbol(shape, Decl(keyofAndIndexedAccess.ts, 146, 9))
+>key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 145, 43))
 }
 
 function f33<S extends Shape, K extends keyof S>(shape: S, key: K) {
->f33 : Symbol(f33, Decl(keyofAndIndexedAccess.ts, 152, 1))
->S : Symbol(S, Decl(keyofAndIndexedAccess.ts, 154, 13))
+>f33 : Symbol(f33, Decl(keyofAndIndexedAccess.ts, 148, 1))
+>S : Symbol(S, Decl(keyofAndIndexedAccess.ts, 150, 13))
 >Shape : Symbol(Shape, Decl(keyofAndIndexedAccess.ts, 0, 0))
->K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 154, 29))
->S : Symbol(S, Decl(keyofAndIndexedAccess.ts, 154, 13))
->shape : Symbol(shape, Decl(keyofAndIndexedAccess.ts, 154, 49))
->S : Symbol(S, Decl(keyofAndIndexedAccess.ts, 154, 13))
->key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 154, 58))
->K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 154, 29))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 150, 29))
+>S : Symbol(S, Decl(keyofAndIndexedAccess.ts, 150, 13))
+>shape : Symbol(shape, Decl(keyofAndIndexedAccess.ts, 150, 49))
+>S : Symbol(S, Decl(keyofAndIndexedAccess.ts, 150, 13))
+>key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 150, 58))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 150, 29))
 
     let name = getProperty(shape, "name");
->name : Symbol(name, Decl(keyofAndIndexedAccess.ts, 155, 7))
+>name : Symbol(name, Decl(keyofAndIndexedAccess.ts, 151, 7))
 >getProperty : Symbol(getProperty, Decl(keyofAndIndexedAccess.ts, 75, 26))
->shape : Symbol(shape, Decl(keyofAndIndexedAccess.ts, 154, 49))
+>shape : Symbol(shape, Decl(keyofAndIndexedAccess.ts, 150, 49))
 
     let prop = getProperty(shape, key);
->prop : Symbol(prop, Decl(keyofAndIndexedAccess.ts, 156, 7))
+>prop : Symbol(prop, Decl(keyofAndIndexedAccess.ts, 152, 7))
 >getProperty : Symbol(getProperty, Decl(keyofAndIndexedAccess.ts, 75, 26))
->shape : Symbol(shape, Decl(keyofAndIndexedAccess.ts, 154, 49))
->key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 154, 58))
+>shape : Symbol(shape, Decl(keyofAndIndexedAccess.ts, 150, 49))
+>key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 150, 58))
 
     return prop;
->prop : Symbol(prop, Decl(keyofAndIndexedAccess.ts, 156, 7))
+>prop : Symbol(prop, Decl(keyofAndIndexedAccess.ts, 152, 7))
 }
 
 function f34(ts: TaggedShape) {
->f34 : Symbol(f34, Decl(keyofAndIndexedAccess.ts, 158, 1))
->ts : Symbol(ts, Decl(keyofAndIndexedAccess.ts, 160, 13))
+>f34 : Symbol(f34, Decl(keyofAndIndexedAccess.ts, 154, 1))
+>ts : Symbol(ts, Decl(keyofAndIndexedAccess.ts, 156, 13))
 >TaggedShape : Symbol(TaggedShape, Decl(keyofAndIndexedAccess.ts, 6, 1))
 
     let tag1 = f33(ts, "tag");
->tag1 : Symbol(tag1, Decl(keyofAndIndexedAccess.ts, 161, 7))
->f33 : Symbol(f33, Decl(keyofAndIndexedAccess.ts, 152, 1))
->ts : Symbol(ts, Decl(keyofAndIndexedAccess.ts, 160, 13))
+>tag1 : Symbol(tag1, Decl(keyofAndIndexedAccess.ts, 157, 7))
+>f33 : Symbol(f33, Decl(keyofAndIndexedAccess.ts, 148, 1))
+>ts : Symbol(ts, Decl(keyofAndIndexedAccess.ts, 156, 13))
 
     let tag2 = getProperty(ts, "tag");
->tag2 : Symbol(tag2, Decl(keyofAndIndexedAccess.ts, 162, 7))
+>tag2 : Symbol(tag2, Decl(keyofAndIndexedAccess.ts, 158, 7))
 >getProperty : Symbol(getProperty, Decl(keyofAndIndexedAccess.ts, 75, 26))
->ts : Symbol(ts, Decl(keyofAndIndexedAccess.ts, 160, 13))
+>ts : Symbol(ts, Decl(keyofAndIndexedAccess.ts, 156, 13))
 }
 
 class C {
->C : Symbol(C, Decl(keyofAndIndexedAccess.ts, 163, 1))
+>C : Symbol(C, Decl(keyofAndIndexedAccess.ts, 159, 1))
 
     public x: string;
->x : Symbol(C.x, Decl(keyofAndIndexedAccess.ts, 165, 9))
+>x : Symbol(C.x, Decl(keyofAndIndexedAccess.ts, 161, 9))
 
     protected y: string;
->y : Symbol(C.y, Decl(keyofAndIndexedAccess.ts, 166, 21))
+>y : Symbol(C.y, Decl(keyofAndIndexedAccess.ts, 162, 21))
 
     private z: string;
->z : Symbol(C.z, Decl(keyofAndIndexedAccess.ts, 167, 24))
+>z : Symbol(C.z, Decl(keyofAndIndexedAccess.ts, 163, 24))
 }
 
 // Indexed access expressions have always permitted access to private and protected members.
 // For consistency we also permit such access in indexed access types.
 function f40(c: C) {
->f40 : Symbol(f40, Decl(keyofAndIndexedAccess.ts, 169, 1))
->c : Symbol(c, Decl(keyofAndIndexedAccess.ts, 173, 13))
->C : Symbol(C, Decl(keyofAndIndexedAccess.ts, 163, 1))
+>f40 : Symbol(f40, Decl(keyofAndIndexedAccess.ts, 165, 1))
+>c : Symbol(c, Decl(keyofAndIndexedAccess.ts, 169, 13))
+>C : Symbol(C, Decl(keyofAndIndexedAccess.ts, 159, 1))
 
     type X = C["x"];
->X : Symbol(X, Decl(keyofAndIndexedAccess.ts, 173, 20))
->C : Symbol(C, Decl(keyofAndIndexedAccess.ts, 163, 1))
+>X : Symbol(X, Decl(keyofAndIndexedAccess.ts, 169, 20))
+>C : Symbol(C, Decl(keyofAndIndexedAccess.ts, 159, 1))
 
     type Y = C["y"];
->Y : Symbol(Y, Decl(keyofAndIndexedAccess.ts, 174, 20))
->C : Symbol(C, Decl(keyofAndIndexedAccess.ts, 163, 1))
+>Y : Symbol(Y, Decl(keyofAndIndexedAccess.ts, 170, 20))
+>C : Symbol(C, Decl(keyofAndIndexedAccess.ts, 159, 1))
 
     type Z = C["z"];
->Z : Symbol(Z, Decl(keyofAndIndexedAccess.ts, 175, 20))
->C : Symbol(C, Decl(keyofAndIndexedAccess.ts, 163, 1))
+>Z : Symbol(Z, Decl(keyofAndIndexedAccess.ts, 171, 20))
+>C : Symbol(C, Decl(keyofAndIndexedAccess.ts, 159, 1))
 
     let x: X = c["x"];
->x : Symbol(x, Decl(keyofAndIndexedAccess.ts, 177, 7))
->X : Symbol(X, Decl(keyofAndIndexedAccess.ts, 173, 20))
->c : Symbol(c, Decl(keyofAndIndexedAccess.ts, 173, 13))
->"x" : Symbol(C.x, Decl(keyofAndIndexedAccess.ts, 165, 9))
+>x : Symbol(x, Decl(keyofAndIndexedAccess.ts, 173, 7))
+>X : Symbol(X, Decl(keyofAndIndexedAccess.ts, 169, 20))
+>c : Symbol(c, Decl(keyofAndIndexedAccess.ts, 169, 13))
+>"x" : Symbol(C.x, Decl(keyofAndIndexedAccess.ts, 161, 9))
 
     let y: Y = c["y"];
->y : Symbol(y, Decl(keyofAndIndexedAccess.ts, 178, 7))
->Y : Symbol(Y, Decl(keyofAndIndexedAccess.ts, 174, 20))
->c : Symbol(c, Decl(keyofAndIndexedAccess.ts, 173, 13))
->"y" : Symbol(C.y, Decl(keyofAndIndexedAccess.ts, 166, 21))
+>y : Symbol(y, Decl(keyofAndIndexedAccess.ts, 174, 7))
+>Y : Symbol(Y, Decl(keyofAndIndexedAccess.ts, 170, 20))
+>c : Symbol(c, Decl(keyofAndIndexedAccess.ts, 169, 13))
+>"y" : Symbol(C.y, Decl(keyofAndIndexedAccess.ts, 162, 21))
 
     let z: Z = c["z"];
->z : Symbol(z, Decl(keyofAndIndexedAccess.ts, 179, 7))
->Z : Symbol(Z, Decl(keyofAndIndexedAccess.ts, 175, 20))
->c : Symbol(c, Decl(keyofAndIndexedAccess.ts, 173, 13))
->"z" : Symbol(C.z, Decl(keyofAndIndexedAccess.ts, 167, 24))
+>z : Symbol(z, Decl(keyofAndIndexedAccess.ts, 175, 7))
+>Z : Symbol(Z, Decl(keyofAndIndexedAccess.ts, 171, 20))
+>c : Symbol(c, Decl(keyofAndIndexedAccess.ts, 169, 13))
+>"z" : Symbol(C.z, Decl(keyofAndIndexedAccess.ts, 163, 24))
+}
+
+function f50<T>(k: keyof T, s: string) {
+>f50 : Symbol(f50, Decl(keyofAndIndexedAccess.ts, 176, 1))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 178, 13))
+>k : Symbol(k, Decl(keyofAndIndexedAccess.ts, 178, 16))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 178, 13))
+>s : Symbol(s, Decl(keyofAndIndexedAccess.ts, 178, 27))
+
+    const x1 = s as keyof T;
+>x1 : Symbol(x1, Decl(keyofAndIndexedAccess.ts, 179, 9))
+>s : Symbol(s, Decl(keyofAndIndexedAccess.ts, 178, 27))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 178, 13))
+
+    const x2 = k as string;
+>x2 : Symbol(x2, Decl(keyofAndIndexedAccess.ts, 180, 9))
+>k : Symbol(k, Decl(keyofAndIndexedAccess.ts, 178, 16))
+}
+
+function f51<T, K extends keyof T>(k: K, s: string) {
+>f51 : Symbol(f51, Decl(keyofAndIndexedAccess.ts, 181, 1))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 183, 13))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 183, 15))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 183, 13))
+>k : Symbol(k, Decl(keyofAndIndexedAccess.ts, 183, 35))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 183, 15))
+>s : Symbol(s, Decl(keyofAndIndexedAccess.ts, 183, 40))
+
+    const x1 = s as keyof T;
+>x1 : Symbol(x1, Decl(keyofAndIndexedAccess.ts, 184, 9))
+>s : Symbol(s, Decl(keyofAndIndexedAccess.ts, 183, 40))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 183, 13))
+
+    const x2 = k as string;
+>x2 : Symbol(x2, Decl(keyofAndIndexedAccess.ts, 185, 9))
+>k : Symbol(k, Decl(keyofAndIndexedAccess.ts, 183, 35))
+}
+
+function f52<T>(obj: { [x: string]: boolean }, k: keyof T, s: string, n: number) {
+>f52 : Symbol(f52, Decl(keyofAndIndexedAccess.ts, 186, 1))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 188, 13))
+>obj : Symbol(obj, Decl(keyofAndIndexedAccess.ts, 188, 16))
+>x : Symbol(x, Decl(keyofAndIndexedAccess.ts, 188, 24))
+>k : Symbol(k, Decl(keyofAndIndexedAccess.ts, 188, 46))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 188, 13))
+>s : Symbol(s, Decl(keyofAndIndexedAccess.ts, 188, 58))
+>n : Symbol(n, Decl(keyofAndIndexedAccess.ts, 188, 69))
+
+    const x1 = obj[s];
+>x1 : Symbol(x1, Decl(keyofAndIndexedAccess.ts, 189, 9))
+>obj : Symbol(obj, Decl(keyofAndIndexedAccess.ts, 188, 16))
+>s : Symbol(s, Decl(keyofAndIndexedAccess.ts, 188, 58))
+
+    const x2 = obj[n];
+>x2 : Symbol(x2, Decl(keyofAndIndexedAccess.ts, 190, 9))
+>obj : Symbol(obj, Decl(keyofAndIndexedAccess.ts, 188, 16))
+>n : Symbol(n, Decl(keyofAndIndexedAccess.ts, 188, 69))
+
+    const x3 = obj[k];
+>x3 : Symbol(x3, Decl(keyofAndIndexedAccess.ts, 191, 9))
+>obj : Symbol(obj, Decl(keyofAndIndexedAccess.ts, 188, 16))
+>k : Symbol(k, Decl(keyofAndIndexedAccess.ts, 188, 46))
+}
+
+function f53<T, K extends keyof T>(obj: { [x: string]: boolean }, k: K, s: string, n: number) {
+>f53 : Symbol(f53, Decl(keyofAndIndexedAccess.ts, 192, 1))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 194, 13))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 194, 15))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 194, 13))
+>obj : Symbol(obj, Decl(keyofAndIndexedAccess.ts, 194, 35))
+>x : Symbol(x, Decl(keyofAndIndexedAccess.ts, 194, 43))
+>k : Symbol(k, Decl(keyofAndIndexedAccess.ts, 194, 65))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 194, 15))
+>s : Symbol(s, Decl(keyofAndIndexedAccess.ts, 194, 71))
+>n : Symbol(n, Decl(keyofAndIndexedAccess.ts, 194, 82))
+
+    const x1 = obj[s];
+>x1 : Symbol(x1, Decl(keyofAndIndexedAccess.ts, 195, 9))
+>obj : Symbol(obj, Decl(keyofAndIndexedAccess.ts, 194, 35))
+>s : Symbol(s, Decl(keyofAndIndexedAccess.ts, 194, 71))
+
+    const x2 = obj[n];
+>x2 : Symbol(x2, Decl(keyofAndIndexedAccess.ts, 196, 9))
+>obj : Symbol(obj, Decl(keyofAndIndexedAccess.ts, 194, 35))
+>n : Symbol(n, Decl(keyofAndIndexedAccess.ts, 194, 82))
+
+    const x3 = obj[k];
+>x3 : Symbol(x3, Decl(keyofAndIndexedAccess.ts, 197, 9))
+>obj : Symbol(obj, Decl(keyofAndIndexedAccess.ts, 194, 35))
+>k : Symbol(k, Decl(keyofAndIndexedAccess.ts, 194, 65))
+}
+
+function f54<T>(obj: T, key: keyof T) {
+>f54 : Symbol(f54, Decl(keyofAndIndexedAccess.ts, 198, 1))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 200, 13))
+>obj : Symbol(obj, Decl(keyofAndIndexedAccess.ts, 200, 16))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 200, 13))
+>key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 200, 23))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 200, 13))
+
+    for (let s in obj[key]) {
+>s : Symbol(s, Decl(keyofAndIndexedAccess.ts, 201, 12))
+>obj : Symbol(obj, Decl(keyofAndIndexedAccess.ts, 200, 16))
+>key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 200, 23))
+    }
+    const b = "foo" in obj[key];
+>b : Symbol(b, Decl(keyofAndIndexedAccess.ts, 203, 9))
+>obj : Symbol(obj, Decl(keyofAndIndexedAccess.ts, 200, 16))
+>key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 200, 23))
+}
+
+function f55<T, K extends keyof T>(obj: T, key: K) {
+>f55 : Symbol(f55, Decl(keyofAndIndexedAccess.ts, 204, 1))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 206, 13))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 206, 15))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 206, 13))
+>obj : Symbol(obj, Decl(keyofAndIndexedAccess.ts, 206, 35))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 206, 13))
+>key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 206, 42))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 206, 15))
+
+    for (let s in obj[key]) {
+>s : Symbol(s, Decl(keyofAndIndexedAccess.ts, 207, 12))
+>obj : Symbol(obj, Decl(keyofAndIndexedAccess.ts, 206, 35))
+>key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 206, 42))
+    }
+    const b = "foo" in obj[key];
+>b : Symbol(b, Decl(keyofAndIndexedAccess.ts, 209, 9))
+>obj : Symbol(obj, Decl(keyofAndIndexedAccess.ts, 206, 35))
+>key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 206, 42))
+}
+
+function f60<T>(source: T, target: T) {
+>f60 : Symbol(f60, Decl(keyofAndIndexedAccess.ts, 210, 1))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 212, 13))
+>source : Symbol(source, Decl(keyofAndIndexedAccess.ts, 212, 16))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 212, 13))
+>target : Symbol(target, Decl(keyofAndIndexedAccess.ts, 212, 26))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 212, 13))
+
+    for (let k in source) {
+>k : Symbol(k, Decl(keyofAndIndexedAccess.ts, 213, 12))
+>source : Symbol(source, Decl(keyofAndIndexedAccess.ts, 212, 16))
+
+        target[k] = source[k];
+>target : Symbol(target, Decl(keyofAndIndexedAccess.ts, 212, 26))
+>k : Symbol(k, Decl(keyofAndIndexedAccess.ts, 213, 12))
+>source : Symbol(source, Decl(keyofAndIndexedAccess.ts, 212, 16))
+>k : Symbol(k, Decl(keyofAndIndexedAccess.ts, 213, 12))
+    }
 }
 
 // Repros from #12011
 
 class Base {
->Base : Symbol(Base, Decl(keyofAndIndexedAccess.ts, 180, 1))
+>Base : Symbol(Base, Decl(keyofAndIndexedAccess.ts, 216, 1))
 
     get<K extends keyof this>(prop: K) {
->get : Symbol(Base.get, Decl(keyofAndIndexedAccess.ts, 184, 12))
->K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 185, 8))
->prop : Symbol(prop, Decl(keyofAndIndexedAccess.ts, 185, 30))
->K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 185, 8))
+>get : Symbol(Base.get, Decl(keyofAndIndexedAccess.ts, 220, 12))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 221, 8))
+>prop : Symbol(prop, Decl(keyofAndIndexedAccess.ts, 221, 30))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 221, 8))
 
         return this[prop];
->this : Symbol(Base, Decl(keyofAndIndexedAccess.ts, 180, 1))
->prop : Symbol(prop, Decl(keyofAndIndexedAccess.ts, 185, 30))
+>this : Symbol(Base, Decl(keyofAndIndexedAccess.ts, 216, 1))
+>prop : Symbol(prop, Decl(keyofAndIndexedAccess.ts, 221, 30))
     }
     set<K extends keyof this>(prop: K, value: this[K]) {
->set : Symbol(Base.set, Decl(keyofAndIndexedAccess.ts, 187, 5))
->K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 188, 8))
->prop : Symbol(prop, Decl(keyofAndIndexedAccess.ts, 188, 30))
->K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 188, 8))
->value : Symbol(value, Decl(keyofAndIndexedAccess.ts, 188, 38))
->K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 188, 8))
+>set : Symbol(Base.set, Decl(keyofAndIndexedAccess.ts, 223, 5))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 224, 8))
+>prop : Symbol(prop, Decl(keyofAndIndexedAccess.ts, 224, 30))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 224, 8))
+>value : Symbol(value, Decl(keyofAndIndexedAccess.ts, 224, 38))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 224, 8))
 
         this[prop] = value;
->this : Symbol(Base, Decl(keyofAndIndexedAccess.ts, 180, 1))
->prop : Symbol(prop, Decl(keyofAndIndexedAccess.ts, 188, 30))
->value : Symbol(value, Decl(keyofAndIndexedAccess.ts, 188, 38))
+>this : Symbol(Base, Decl(keyofAndIndexedAccess.ts, 216, 1))
+>prop : Symbol(prop, Decl(keyofAndIndexedAccess.ts, 224, 30))
+>value : Symbol(value, Decl(keyofAndIndexedAccess.ts, 224, 38))
     }
 }
 
 class Person extends Base {
->Person : Symbol(Person, Decl(keyofAndIndexedAccess.ts, 191, 1))
->Base : Symbol(Base, Decl(keyofAndIndexedAccess.ts, 180, 1))
+>Person : Symbol(Person, Decl(keyofAndIndexedAccess.ts, 227, 1))
+>Base : Symbol(Base, Decl(keyofAndIndexedAccess.ts, 216, 1))
 
     parts: number;
->parts : Symbol(Person.parts, Decl(keyofAndIndexedAccess.ts, 193, 27))
+>parts : Symbol(Person.parts, Decl(keyofAndIndexedAccess.ts, 229, 27))
 
     constructor(parts: number) {
->parts : Symbol(parts, Decl(keyofAndIndexedAccess.ts, 195, 16))
+>parts : Symbol(parts, Decl(keyofAndIndexedAccess.ts, 231, 16))
 
         super();
->super : Symbol(Base, Decl(keyofAndIndexedAccess.ts, 180, 1))
+>super : Symbol(Base, Decl(keyofAndIndexedAccess.ts, 216, 1))
 
         this.set("parts", parts);
->this.set : Symbol(Base.set, Decl(keyofAndIndexedAccess.ts, 187, 5))
->this : Symbol(Person, Decl(keyofAndIndexedAccess.ts, 191, 1))
->set : Symbol(Base.set, Decl(keyofAndIndexedAccess.ts, 187, 5))
->parts : Symbol(parts, Decl(keyofAndIndexedAccess.ts, 195, 16))
+>this.set : Symbol(Base.set, Decl(keyofAndIndexedAccess.ts, 223, 5))
+>this : Symbol(Person, Decl(keyofAndIndexedAccess.ts, 227, 1))
+>set : Symbol(Base.set, Decl(keyofAndIndexedAccess.ts, 223, 5))
+>parts : Symbol(parts, Decl(keyofAndIndexedAccess.ts, 231, 16))
     }
     getParts() {
->getParts : Symbol(Person.getParts, Decl(keyofAndIndexedAccess.ts, 198, 5))
+>getParts : Symbol(Person.getParts, Decl(keyofAndIndexedAccess.ts, 234, 5))
 
         return this.get("parts")
->this.get : Symbol(Base.get, Decl(keyofAndIndexedAccess.ts, 184, 12))
->this : Symbol(Person, Decl(keyofAndIndexedAccess.ts, 191, 1))
->get : Symbol(Base.get, Decl(keyofAndIndexedAccess.ts, 184, 12))
+>this.get : Symbol(Base.get, Decl(keyofAndIndexedAccess.ts, 220, 12))
+>this : Symbol(Person, Decl(keyofAndIndexedAccess.ts, 227, 1))
+>get : Symbol(Base.get, Decl(keyofAndIndexedAccess.ts, 220, 12))
     }
 }
 
 class OtherPerson {
->OtherPerson : Symbol(OtherPerson, Decl(keyofAndIndexedAccess.ts, 202, 1))
+>OtherPerson : Symbol(OtherPerson, Decl(keyofAndIndexedAccess.ts, 238, 1))
 
     parts: number;
->parts : Symbol(OtherPerson.parts, Decl(keyofAndIndexedAccess.ts, 204, 19))
+>parts : Symbol(OtherPerson.parts, Decl(keyofAndIndexedAccess.ts, 240, 19))
 
     constructor(parts: number) {
->parts : Symbol(parts, Decl(keyofAndIndexedAccess.ts, 206, 16))
+>parts : Symbol(parts, Decl(keyofAndIndexedAccess.ts, 242, 16))
 
         setProperty(this, "parts", parts);
 >setProperty : Symbol(setProperty, Decl(keyofAndIndexedAccess.ts, 79, 1))
->this : Symbol(OtherPerson, Decl(keyofAndIndexedAccess.ts, 202, 1))
->parts : Symbol(parts, Decl(keyofAndIndexedAccess.ts, 206, 16))
+>this : Symbol(OtherPerson, Decl(keyofAndIndexedAccess.ts, 238, 1))
+>parts : Symbol(parts, Decl(keyofAndIndexedAccess.ts, 242, 16))
     }
     getParts() {
->getParts : Symbol(OtherPerson.getParts, Decl(keyofAndIndexedAccess.ts, 208, 5))
+>getParts : Symbol(OtherPerson.getParts, Decl(keyofAndIndexedAccess.ts, 244, 5))
 
         return getProperty(this, "parts")
 >getProperty : Symbol(getProperty, Decl(keyofAndIndexedAccess.ts, 75, 26))
->this : Symbol(OtherPerson, Decl(keyofAndIndexedAccess.ts, 202, 1))
+>this : Symbol(OtherPerson, Decl(keyofAndIndexedAccess.ts, 238, 1))
     }
 }

tests/baselines/reference/keyofAndIndexedAccess.types

@@ -54,10 +54,10 @@ const enum E { A, B, C }
 >C : E.C
 
 type K00 = keyof any;  // string | number
->K00 : string | number
+>K00 : string
 
 type K01 = keyof string;  // number | "toString" | "charAt" | ...
->K01 : number | "length" | "toString" | "concat" | "slice" | "indexOf" | "lastIndexOf" | "charAt" | "charCodeAt" | "localeCompare" | "match" | "replace" | "search" | "split" | "substring" | "toLowerCase" | "toLocaleLowerCase" | "toUpperCase" | "toLocaleUpperCase" | "trim" | "substr" | "valueOf"
+>K01 : "length" | "toString" | "concat" | "slice" | "indexOf" | "lastIndexOf" | "charAt" | "charCodeAt" | "localeCompare" | "match" | "replace" | "search" | "split" | "substring" | "toLowerCase" | "toLocaleLowerCase" | "toUpperCase" | "toLocaleUpperCase" | "trim" | "substr" | "valueOf"
 
 type K02 = keyof number;  // "toString" | "toFixed" | "toExponential" | ...
 >K02 : "toString" | "toLocaleString" | "valueOf" | "toFixed" | "toExponential" | "toPrecision"
@@ -83,11 +83,11 @@ type K10 = keyof Shape;  // "name" | "width" | "height" | "visible"
 >Shape : Shape
 
 type K11 = keyof Shape[];  // number | "length" | "toString" | ...
->K11 : number | "length" | "toString" | "toLocaleString" | "push" | "pop" | "concat" | "join" | "reverse" | "shift" | "slice" | "sort" | "splice" | "unshift" | "indexOf" | "lastIndexOf" | "every" | "some" | "forEach" | "map" | "filter" | "reduce" | "reduceRight"
+>K11 : "length" | "toString" | "toLocaleString" | "push" | "pop" | "concat" | "join" | "reverse" | "shift" | "slice" | "sort" | "splice" | "unshift" | "indexOf" | "lastIndexOf" | "every" | "some" | "forEach" | "map" | "filter" | "reduce" | "reduceRight"
 >Shape : Shape
 
 type K12 = keyof Dictionary<Shape>;  // string | number
->K12 : string | number
+>K12 : string
 >Dictionary : Dictionary<T>
 >Shape : Shape
 
@@ -103,7 +103,7 @@ type K15 = keyof E;  // "toString" | "toFixed" | "toExponential" | ...
 >E : E
 
 type K16 = keyof [string, number];  // number | "0" | "1" | "length" | "toString" | ...
->K16 : number | "0" | "1" | "length" | "toString" | "toLocaleString" | "push" | "pop" | "concat" | "join" | "reverse" | "shift" | "slice" | "sort" | "splice" | "unshift" | "indexOf" | "lastIndexOf" | "every" | "some" | "forEach" | "map" | "filter" | "reduce" | "reduceRight"
+>K16 : "0" | "1" | "length" | "toString" | "toLocaleString" | "push" | "pop" | "concat" | "join" | "reverse" | "shift" | "slice" | "sort" | "splice" | "unshift" | "indexOf" | "lastIndexOf" | "every" | "some" | "forEach" | "map" | "filter" | "reduce" | "reduceRight"
 
 type K17 = keyof (Shape | Item);  // "name"
 >K17 : "name"
@@ -126,7 +126,7 @@ type K20 = KeyOf<Shape>;  // "name" | "width" | "height" | "visible"
 >Shape : Shape
 
 type K21 = KeyOf<Dictionary<Shape>>;  // string | number
->K21 : string | number
+>K21 : string
 >KeyOf : keyof T
 >Dictionary : Dictionary<T>
 >Shape : Shape
@@ -328,22 +328,12 @@ function f11(a: Shape[]) {
 >a : Shape[]
 >"length" : "length"
 
-    let shape = getProperty(a, 1000);    // Shape
->shape : Shape
->getProperty(a, 1000) : Shape
->getProperty : <T, K extends keyof T>(obj: T, key: K) => T[K]
->a : Shape[]
->1000 : 1000
-
-    setProperty(a, 1000, getProperty(a, 1001));
->setProperty(a, 1000, getProperty(a, 1001)) : void
+    setProperty(a, "length", len);
+>setProperty(a, "length", len) : void
 >setProperty : <T, K extends keyof T>(obj: T, key: K, value: T[K]) => void
 >a : Shape[]
->1000 : 1000
->getProperty(a, 1001) : Shape
->getProperty : <T, K extends keyof T>(obj: T, key: K) => T[K]
->a : Shape[]
->1001 : 1001
+>"length" : "length"
+>len : number
 }
 
 function f12(t: [Shape, boolean]) {
@@ -358,13 +348,6 @@ function f12(t: [Shape, boolean]) {
 >t : [Shape, boolean]
 >"length" : "length"
 
-    let s1 = getProperty(t, 0);    // Shape
->s1 : Shape
->getProperty(t, 0) : Shape
->getProperty : <T, K extends keyof T>(obj: T, key: K) => T[K]
->t : [Shape, boolean]
->0 : 0
-
     let s2 = getProperty(t, "0");  // Shape
 >s2 : Shape
 >getProperty(t, "0") : Shape
@@ -372,26 +355,12 @@ function f12(t: [Shape, boolean]) {
 >t : [Shape, boolean]
 >"0" : "0"
 
-    let b1 = getProperty(t, 1);    // boolean
->b1 : boolean
->getProperty(t, 1) : boolean
->getProperty : <T, K extends keyof T>(obj: T, key: K) => T[K]
->t : [Shape, boolean]
->1 : 1
-
     let b2 = getProperty(t, "1");  // boolean
 >b2 : boolean
 >getProperty(t, "1") : boolean
 >getProperty : <T, K extends keyof T>(obj: T, key: K) => T[K]
 >t : [Shape, boolean]
 >"1" : "1"
-
-    let x1 = getProperty(t, 2);    // Shape | boolean
->x1 : boolean | Shape
->getProperty(t, 2) : boolean | Shape
->getProperty : <T, K extends keyof T>(obj: T, key: K) => T[K]
->t : [Shape, boolean]
->2 : 2
 }
 
 function f13(foo: any, bar: any) {
@@ -406,12 +375,12 @@ function f13(foo: any, bar: any) {
 >foo : any
 >"x" : "x"
 
-    let y = getProperty(foo, 100);  // any
+    let y = getProperty(foo, "100");  // any
 >y : any
->getProperty(foo, 100) : any
+>getProperty(foo, "100") : any
 >getProperty : <T, K extends keyof T>(obj: T, key: K) => T[K]
 >foo : any
->100 : 100
+>"100" : "100"
 
     let z = getProperty(foo, bar);  // any
 >z : any
@@ -737,6 +706,177 @@ function f40(c: C) {
 >"z" : "z"
 }
 
+function f50<T>(k: keyof T, s: string) {
+>f50 : <T>(k: keyof T, s: string) => void
+>T : T
+>k : keyof T
+>T : T
+>s : string
+
+    const x1 = s as keyof T;
+>x1 : keyof T
+>s as keyof T : keyof T
+>s : string
+>T : T
+
+    const x2 = k as string;
+>x2 : string
+>k as string : string
+>k : keyof T
+}
+
+function f51<T, K extends keyof T>(k: K, s: string) {
+>f51 : <T, K extends keyof T>(k: K, s: string) => void
+>T : T
+>K : K
+>T : T
+>k : K
+>K : K
+>s : string
+
+    const x1 = s as keyof T;
+>x1 : keyof T
+>s as keyof T : keyof T
+>s : string
+>T : T
+
+    const x2 = k as string;
+>x2 : string
+>k as string : string
+>k : K
+}
+
+function f52<T>(obj: { [x: string]: boolean }, k: keyof T, s: string, n: number) {
+>f52 : <T>(obj: { [x: string]: boolean; }, k: keyof T, s: string, n: number) => void
+>T : T
+>obj : { [x: string]: boolean; }
+>x : string
+>k : keyof T
+>T : T
+>s : string
+>n : number
+
+    const x1 = obj[s];
+>x1 : boolean
+>obj[s] : boolean
+>obj : { [x: string]: boolean; }
+>s : string
+
+    const x2 = obj[n];
+>x2 : boolean
+>obj[n] : boolean
+>obj : { [x: string]: boolean; }
+>n : number
+
+    const x3 = obj[k];
+>x3 : boolean
+>obj[k] : boolean
+>obj : { [x: string]: boolean; }
+>k : keyof T
+}
+
+function f53<T, K extends keyof T>(obj: { [x: string]: boolean }, k: K, s: string, n: number) {
+>f53 : <T, K extends keyof T>(obj: { [x: string]: boolean; }, k: K, s: string, n: number) => void
+>T : T
+>K : K
+>T : T
+>obj : { [x: string]: boolean; }
+>x : string
+>k : K
+>K : K
+>s : string
+>n : number
+
+    const x1 = obj[s];
+>x1 : boolean
+>obj[s] : boolean
+>obj : { [x: string]: boolean; }
+>s : string
+
+    const x2 = obj[n];
+>x2 : boolean
+>obj[n] : boolean
+>obj : { [x: string]: boolean; }
+>n : number
+
+    const x3 = obj[k];
+>x3 : { [x: string]: boolean; }[K]
+>obj[k] : { [x: string]: boolean; }[K]
+>obj : { [x: string]: boolean; }
+>k : K
+}
+
+function f54<T>(obj: T, key: keyof T) {
+>f54 : <T>(obj: T, key: keyof T) => void
+>T : T
+>obj : T
+>T : T
+>key : keyof T
+>T : T
+
+    for (let s in obj[key]) {
+>s : string
+>obj[key] : T[keyof T]
+>obj : T
+>key : keyof T
+    }
+    const b = "foo" in obj[key];
+>b : boolean
+>"foo" in obj[key] : boolean
+>"foo" : "foo"
+>obj[key] : T[keyof T]
+>obj : T
+>key : keyof T
+}
+
+function f55<T, K extends keyof T>(obj: T, key: K) {
+>f55 : <T, K extends keyof T>(obj: T, key: K) => void
+>T : T
+>K : K
+>T : T
+>obj : T
+>T : T
+>key : K
+>K : K
+
+    for (let s in obj[key]) {
+>s : string
+>obj[key] : T[K]
+>obj : T
+>key : K
+    }
+    const b = "foo" in obj[key];
+>b : boolean
+>"foo" in obj[key] : boolean
+>"foo" : "foo"
+>obj[key] : T[K]
+>obj : T
+>key : K
+}
+
+function f60<T>(source: T, target: T) {
+>f60 : <T>(source: T, target: T) => void
+>T : T
+>source : T
+>T : T
+>target : T
+>T : T
+
+    for (let k in source) {
+>k : keyof T
+>source : T
+
+        target[k] = source[k];
+>target[k] = source[k] : T[keyof T]
+>target[k] : T[keyof T]
+>target : T
+>k : keyof T
+>source[k] : T[keyof T]
+>source : T
+>k : keyof T
+    }
+}
+
 // Repros from #12011
 
 class Base {

tests/baselines/reference/mappedTypeErrors.errors.txt

@@ -1,29 +1,28 @@
 tests/cases/conformance/types/mapped/mappedTypeErrors.ts(20,20): error TS2313: Type parameter 'P' has a circular constraint.
-tests/cases/conformance/types/mapped/mappedTypeErrors.ts(21,20): error TS2322: Type 'Date' is not assignable to type 'string | number'.
-  Type 'Date' is not assignable to type 'number'.
-tests/cases/conformance/types/mapped/mappedTypeErrors.ts(22,19): error TS2344: Type 'Date' does not satisfy the constraint 'string | number'.
-  Type 'Date' is not assignable to type 'number'.
-tests/cases/conformance/types/mapped/mappedTypeErrors.ts(25,24): error TS2344: Type '"foo"' does not satisfy the constraint '"name" | "width" | "height" | "visible"'.
-tests/cases/conformance/types/mapped/mappedTypeErrors.ts(26,24): error TS2344: Type '"name" | "foo"' does not satisfy the constraint '"name" | "width" | "height" | "visible"'.
+tests/cases/conformance/types/mapped/mappedTypeErrors.ts(21,20): error TS2322: Type 'number' is not assignable to type 'string'.
+tests/cases/conformance/types/mapped/mappedTypeErrors.ts(22,20): error TS2322: Type 'Date' is not assignable to type 'string'.
+tests/cases/conformance/types/mapped/mappedTypeErrors.ts(23,19): error TS2344: Type 'Date' does not satisfy the constraint 'string'.
+tests/cases/conformance/types/mapped/mappedTypeErrors.ts(26,24): error TS2344: Type '"foo"' does not satisfy the constraint '"name" | "width" | "height" | "visible"'.
+tests/cases/conformance/types/mapped/mappedTypeErrors.ts(27,24): error TS2344: Type '"name" | "foo"' does not satisfy the constraint '"name" | "width" | "height" | "visible"'.
   Type '"foo"' is not assignable to type '"name" | "width" | "height" | "visible"'.
-tests/cases/conformance/types/mapped/mappedTypeErrors.ts(28,24): error TS2344: Type '"x" | "y"' does not satisfy the constraint '"name" | "width" | "height" | "visible"'.
+tests/cases/conformance/types/mapped/mappedTypeErrors.ts(29,24): error TS2344: Type '"x" | "y"' does not satisfy the constraint '"name" | "width" | "height" | "visible"'.
   Type '"x"' is not assignable to type '"name" | "width" | "height" | "visible"'.
-tests/cases/conformance/types/mapped/mappedTypeErrors.ts(30,24): error TS2344: Type 'undefined' does not satisfy the constraint '"name" | "width" | "height" | "visible"'.
-tests/cases/conformance/types/mapped/mappedTypeErrors.ts(33,24): error TS2344: Type 'T' does not satisfy the constraint '"name" | "width" | "height" | "visible"'.
+tests/cases/conformance/types/mapped/mappedTypeErrors.ts(31,24): error TS2344: Type 'undefined' does not satisfy the constraint '"name" | "width" | "height" | "visible"'.
+tests/cases/conformance/types/mapped/mappedTypeErrors.ts(34,24): error TS2344: Type 'T' does not satisfy the constraint '"name" | "width" | "height" | "visible"'.
   Type 'T' is not assignable to type '"visible"'.
-tests/cases/conformance/types/mapped/mappedTypeErrors.ts(37,24): error TS2344: Type 'T' does not satisfy the constraint '"name" | "width" | "height" | "visible"'.
+tests/cases/conformance/types/mapped/mappedTypeErrors.ts(38,24): error TS2344: Type 'T' does not satisfy the constraint '"name" | "width" | "height" | "visible"'.
   Type 'string | number' is not assignable to type '"name" | "width" | "height" | "visible"'.
     Type 'string' is not assignable to type '"name" | "width" | "height" | "visible"'.
       Type 'T' is not assignable to type '"visible"'.
         Type 'string | number' is not assignable to type '"visible"'.
           Type 'string' is not assignable to type '"visible"'.
-tests/cases/conformance/types/mapped/mappedTypeErrors.ts(59,9): error TS2403: Subsequent variable declarations must have the same type.  Variable 'x' must be of type '{ [P in keyof T]: T[P]; }', but here has type '{ [P in keyof T]?: T[P]; }'.
-tests/cases/conformance/types/mapped/mappedTypeErrors.ts(60,9): error TS2403: Subsequent variable declarations must have the same type.  Variable 'x' must be of type '{ [P in keyof T]: T[P]; }', but here has type '{ readonly [P in keyof T]: T[P]; }'.
-tests/cases/conformance/types/mapped/mappedTypeErrors.ts(61,9): error TS2403: Subsequent variable declarations must have the same type.  Variable 'x' must be of type '{ [P in keyof T]: T[P]; }', but here has type '{ readonly [P in keyof T]?: T[P]; }'.
-tests/cases/conformance/types/mapped/mappedTypeErrors.ts(66,9): error TS2403: Subsequent variable declarations must have the same type.  Variable 'x' must be of type '{ [P in keyof T]: T[P]; }', but here has type '{ [P in keyof T]: T[P][]; }'.
+tests/cases/conformance/types/mapped/mappedTypeErrors.ts(60,9): error TS2403: Subsequent variable declarations must have the same type.  Variable 'x' must be of type '{ [P in keyof T]: T[P]; }', but here has type '{ [P in keyof T]?: T[P]; }'.
+tests/cases/conformance/types/mapped/mappedTypeErrors.ts(61,9): error TS2403: Subsequent variable declarations must have the same type.  Variable 'x' must be of type '{ [P in keyof T]: T[P]; }', but here has type '{ readonly [P in keyof T]: T[P]; }'.
+tests/cases/conformance/types/mapped/mappedTypeErrors.ts(62,9): error TS2403: Subsequent variable declarations must have the same type.  Variable 'x' must be of type '{ [P in keyof T]: T[P]; }', but here has type '{ readonly [P in keyof T]?: T[P]; }'.
+tests/cases/conformance/types/mapped/mappedTypeErrors.ts(67,9): error TS2403: Subsequent variable declarations must have the same type.  Variable 'x' must be of type '{ [P in keyof T]: T[P]; }', but here has type '{ [P in keyof T]: T[P][]; }'.
 
 
-==== tests/cases/conformance/types/mapped/mappedTypeErrors.ts (13 errors) ====
+==== tests/cases/conformance/types/mapped/mappedTypeErrors.ts (14 errors) ====
     
     interface Shape {
         name: string;
@@ -46,14 +45,15 @@ tests/cases/conformance/types/mapped/mappedTypeErrors.ts(66,9): error TS2403: Su
     type T00 = { [P in P]: string };  // Error
                        ~
 !!! error TS2313: Type parameter 'P' has a circular constraint.
-    type T01 = { [P in Date]: number };  // Error
+    type T01 = { [P in number]: string };  // Error
+                       ~~~~~~
+!!! error TS2322: Type 'number' is not assignable to type 'string'.
+    type T02 = { [P in Date]: number };  // Error
                        ~~~~
-!!! error TS2322: Type 'Date' is not assignable to type 'string | number'.
-!!! error TS2322:   Type 'Date' is not assignable to type 'number'.
-    type T02 = Record<Date, number>;  // Error
+!!! error TS2322: Type 'Date' is not assignable to type 'string'.
+    type T03 = Record<Date, number>;  // Error
                       ~~~~
-!!! error TS2344: Type 'Date' does not satisfy the constraint 'string | number'.
-!!! error TS2344:   Type 'Date' is not assignable to type 'number'.
+!!! error TS2344: Type 'Date' does not satisfy the constraint 'string'.
     
     type T10 = Pick<Shape, "name">;
     type T11 = Pick<Shape, "foo">;  // Error

tests/baselines/reference/mappedTypeErrors.js

@@ -19,8 +19,9 @@ interface Point {
 // Constraint checking
 
 type T00 = { [P in P]: string };  // Error
-type T01 = { [P in Date]: number };  // Error
-type T02 = Record<Date, number>;  // Error
+type T01 = { [P in number]: string };  // Error
+type T02 = { [P in Date]: number };  // Error
+type T03 = Record<Date, number>;  // Error
 
 type T10 = Pick<Shape, "name">;
 type T11 = Pick<Shape, "foo">;  // Error
@@ -116,9 +117,12 @@ declare type T00 = {
     [P in P]: string;
 };
 declare type T01 = {
+    [P in number]: string;
+};
+declare type T02 = {
     [P in Date]: number;
 };
-declare type T02 = Record<Date, number>;
+declare type T03 = Record<Date, number>;
 declare type T10 = Pick<Shape, "name">;
 declare type T11 = Pick<Shape, "foo">;
 declare type T12 = Pick<Shape, "name" | "foo">;

tests/baselines/reference/mappedTypes1.js

@@ -26,13 +26,9 @@ type T37 = { [P in keyof symbol]: void };
 type T38 = { [P in keyof never]: void };
 
 type T40 = { [P in string]: void };
-type T41 = { [P in number]: void };
-type T42 = { [P in string | number]: void };
-type T43 = { [P in "a" | "b" | 0 | 1]: void };
+type T43 = { [P in "a" | "b"]: void };
 type T44 = { [P in "a" | "b" | "0" | "1"]: void };
-type T45 = { [P in "a" | "b" | "0" | "1" | 0 | 1]: void };
-type T46 = { [P in number | "a" | "b" | 0 | 1]: void };
-type T47 = { [P in string | number | "a" | "b" | 0 | 1]: void };
+type T47 = { [P in string | "a" | "b" | "0" | "1"]: void };
 
 declare function f1<T1>(): { [P in keyof T1]: void };
 declare function f2<T1 extends string>(): { [P in keyof T1]: void };
@@ -114,26 +110,14 @@ declare type T38 = {
 declare type T40 = {
     [P in string]: void;
 };
-declare type T41 = {
-    [P in number]: void;
-};
-declare type T42 = {
-    [P in string | number]: void;
-};
 declare type T43 = {
-    [P in "a" | "b" | 0 | 1]: void;
+    [P in "a" | "b"]: void;
 };
 declare type T44 = {
     [P in "a" | "b" | "0" | "1"]: void;
 };
-declare type T45 = {
-    [P in "a" | "b" | "0" | "1" | 0 | 1]: void;
-};
-declare type T46 = {
-    [P in number | "a" | "b" | 0 | 1]: void;
-};
 declare type T47 = {
-    [P in string | number | "a" | "b" | 0 | 1]: void;
+    [P in string | "a" | "b" | "0" | "1"]: void;
 };
 declare function f1<T1>(): {
     [P in keyof T1]: void;
@@ -146,7 +130,6 @@ declare function f3<T1 extends number>(): {
 };
 declare let x1: {};
 declare let x2: {
-    [x: number]: void;
     toString: void;
     charAt: void;
     charCodeAt: void;

tests/baselines/reference/mappedTypes1.symbols

@@ -110,61 +110,45 @@ type T40 = { [P in string]: void };
 >T40 : Symbol(T40, Decl(mappedTypes1.ts, 24, 40))
 >P : Symbol(P, Decl(mappedTypes1.ts, 26, 14))
 
-type T41 = { [P in number]: void };
->T41 : Symbol(T41, Decl(mappedTypes1.ts, 26, 35))
+type T43 = { [P in "a" | "b"]: void };
+>T43 : Symbol(T43, Decl(mappedTypes1.ts, 26, 35))
 >P : Symbol(P, Decl(mappedTypes1.ts, 27, 14))
 
-type T42 = { [P in string | number]: void };
->T42 : Symbol(T42, Decl(mappedTypes1.ts, 27, 35))
+type T44 = { [P in "a" | "b" | "0" | "1"]: void };
+>T44 : Symbol(T44, Decl(mappedTypes1.ts, 27, 38))
 >P : Symbol(P, Decl(mappedTypes1.ts, 28, 14))
 
-type T43 = { [P in "a" | "b" | 0 | 1]: void };
->T43 : Symbol(T43, Decl(mappedTypes1.ts, 28, 44))
+type T47 = { [P in string | "a" | "b" | "0" | "1"]: void };
+>T47 : Symbol(T47, Decl(mappedTypes1.ts, 28, 50))
 >P : Symbol(P, Decl(mappedTypes1.ts, 29, 14))
 
-type T44 = { [P in "a" | "b" | "0" | "1"]: void };
->T44 : Symbol(T44, Decl(mappedTypes1.ts, 29, 46))
->P : Symbol(P, Decl(mappedTypes1.ts, 30, 14))
-
-type T45 = { [P in "a" | "b" | "0" | "1" | 0 | 1]: void };
->T45 : Symbol(T45, Decl(mappedTypes1.ts, 30, 50))
->P : Symbol(P, Decl(mappedTypes1.ts, 31, 14))
-
-type T46 = { [P in number | "a" | "b" | 0 | 1]: void };
->T46 : Symbol(T46, Decl(mappedTypes1.ts, 31, 58))
->P : Symbol(P, Decl(mappedTypes1.ts, 32, 14))
-
-type T47 = { [P in string | number | "a" | "b" | 0 | 1]: void };
->T47 : Symbol(T47, Decl(mappedTypes1.ts, 32, 55))
->P : Symbol(P, Decl(mappedTypes1.ts, 33, 14))
-
 declare function f1<T1>(): { [P in keyof T1]: void };
->f1 : Symbol(f1, Decl(mappedTypes1.ts, 33, 64))
->T1 : Symbol(T1, Decl(mappedTypes1.ts, 35, 20))
->P : Symbol(P, Decl(mappedTypes1.ts, 35, 30))
->T1 : Symbol(T1, Decl(mappedTypes1.ts, 35, 20))
+>f1 : Symbol(f1, Decl(mappedTypes1.ts, 29, 59))
+>T1 : Symbol(T1, Decl(mappedTypes1.ts, 31, 20))
+>P : Symbol(P, Decl(mappedTypes1.ts, 31, 30))
+>T1 : Symbol(T1, Decl(mappedTypes1.ts, 31, 20))
 
 declare function f2<T1 extends string>(): { [P in keyof T1]: void };
->f2 : Symbol(f2, Decl(mappedTypes1.ts, 35, 53))
->T1 : Symbol(T1, Decl(mappedTypes1.ts, 36, 20))
->P : Symbol(P, Decl(mappedTypes1.ts, 36, 45))
->T1 : Symbol(T1, Decl(mappedTypes1.ts, 36, 20))
+>f2 : Symbol(f2, Decl(mappedTypes1.ts, 31, 53))
+>T1 : Symbol(T1, Decl(mappedTypes1.ts, 32, 20))
+>P : Symbol(P, Decl(mappedTypes1.ts, 32, 45))
+>T1 : Symbol(T1, Decl(mappedTypes1.ts, 32, 20))
 
 declare function f3<T1 extends number>(): { [P in keyof T1]: void };
->f3 : Symbol(f3, Decl(mappedTypes1.ts, 36, 68))
->T1 : Symbol(T1, Decl(mappedTypes1.ts, 37, 20))
->P : Symbol(P, Decl(mappedTypes1.ts, 37, 45))
->T1 : Symbol(T1, Decl(mappedTypes1.ts, 37, 20))
+>f3 : Symbol(f3, Decl(mappedTypes1.ts, 32, 68))
+>T1 : Symbol(T1, Decl(mappedTypes1.ts, 33, 20))
+>P : Symbol(P, Decl(mappedTypes1.ts, 33, 45))
+>T1 : Symbol(T1, Decl(mappedTypes1.ts, 33, 20))
 
 let x1 = f1();
->x1 : Symbol(x1, Decl(mappedTypes1.ts, 39, 3))
->f1 : Symbol(f1, Decl(mappedTypes1.ts, 33, 64))
+>x1 : Symbol(x1, Decl(mappedTypes1.ts, 35, 3))
+>f1 : Symbol(f1, Decl(mappedTypes1.ts, 29, 59))
 
 let x2 = f2();
->x2 : Symbol(x2, Decl(mappedTypes1.ts, 40, 3))
->f2 : Symbol(f2, Decl(mappedTypes1.ts, 35, 53))
+>x2 : Symbol(x2, Decl(mappedTypes1.ts, 36, 3))
+>f2 : Symbol(f2, Decl(mappedTypes1.ts, 31, 53))
 
 let x3 = f3();
->x3 : Symbol(x3, Decl(mappedTypes1.ts, 41, 3))
->f3 : Symbol(f3, Decl(mappedTypes1.ts, 36, 68))
+>x3 : Symbol(x3, Decl(mappedTypes1.ts, 37, 3))
+>f3 : Symbol(f3, Decl(mappedTypes1.ts, 32, 68))
 

tests/baselines/reference/mappedTypes1.types

@@ -112,15 +112,7 @@ type T40 = { [P in string]: void };
 >T40 : T40
 >P : P
 
-type T41 = { [P in number]: void };
->T41 : T41
->P : P
-
-type T42 = { [P in string | number]: void };
->T42 : T42
->P : P
-
-type T43 = { [P in "a" | "b" | 0 | 1]: void };
+type T43 = { [P in "a" | "b"]: void };
 >T43 : T43
 >P : P
 
@@ -128,15 +120,7 @@ type T44 = { [P in "a" | "b" | "0" | "1"]: void };
 >T44 : T44
 >P : P
 
-type T45 = { [P in "a" | "b" | "0" | "1" | 0 | 1]: void };
->T45 : T45
->P : P
-
-type T46 = { [P in number | "a" | "b" | 0 | 1]: void };
->T46 : T46
->P : P
-
-type T47 = { [P in string | number | "a" | "b" | 0 | 1]: void };
+type T47 = { [P in string | "a" | "b" | "0" | "1"]: void };
 >T47 : T47
 >P : P
 
@@ -164,8 +148,8 @@ let x1 = f1();
 >f1 : <T1>() => { [P in keyof T1]: void; }
 
 let x2 = f2();
->x2 : { [x: number]: void; toString: void; charAt: void; charCodeAt: void; concat: void; indexOf: void; lastIndexOf: void; localeCompare: void; match: void; replace: void; search: void; slice: void; split: void; substring: void; toLowerCase: void; toLocaleLowerCase: void; toUpperCase: void; toLocaleUpperCase: void; trim: void; length: void; substr: void; valueOf: void; }
->f2() : { [x: number]: void; toString: void; charAt: void; charCodeAt: void; concat: void; indexOf: void; lastIndexOf: void; localeCompare: void; match: void; replace: void; search: void; slice: void; split: void; substring: void; toLowerCase: void; toLocaleLowerCase: void; toUpperCase: void; toLocaleUpperCase: void; trim: void; length: void; substr: void; valueOf: void; }
+>x2 : { toString: void; charAt: void; charCodeAt: void; concat: void; indexOf: void; lastIndexOf: void; localeCompare: void; match: void; replace: void; search: void; slice: void; split: void; substring: void; toLowerCase: void; toLocaleLowerCase: void; toUpperCase: void; toLocaleUpperCase: void; trim: void; length: void; substr: void; valueOf: void; }
+>f2() : { toString: void; charAt: void; charCodeAt: void; concat: void; indexOf: void; lastIndexOf: void; localeCompare: void; match: void; replace: void; search: void; slice: void; split: void; substring: void; toLowerCase: void; toLocaleLowerCase: void; toUpperCase: void; toLocaleUpperCase: void; trim: void; length: void; substr: void; valueOf: void; }
 >f2 : <T1 extends string>() => { [P in keyof T1]: void; }
 
 let x3 = f3();

tests/baselines/reference/mappedTypes2.js

@@ -27,7 +27,7 @@ type DeepReadonly<T> = {
 declare function assign<T>(obj: T, props: Partial<T>): void;
 declare function freeze<T>(obj: T): Readonly<T>;
 declare function pick<T, K extends keyof T>(obj: T, ...keys: K[]): Pick<T, K>;
-declare function mapObject<K extends string | number, T, U>(obj: Record<K, T>, f: (x: T) => U): Record<K, U>;
+declare function mapObject<K extends string, T, U>(obj: Record<K, T>, f: (x: T) => U): Record<K, U>;
 declare function proxify<T>(obj: T): Proxify<T>;
 
 interface Shape {
@@ -148,7 +148,7 @@ declare type DeepReadonly<T> = {
 declare function assign<T>(obj: T, props: Partial<T>): void;
 declare function freeze<T>(obj: T): Readonly<T>;
 declare function pick<T, K extends keyof T>(obj: T, ...keys: K[]): Pick<T, K>;
-declare function mapObject<K extends string | number, T, U>(obj: Record<K, T>, f: (x: T) => U): Record<K, U>;
+declare function mapObject<K extends string, T, U>(obj: Record<K, T>, f: (x: T) => U): Record<K, U>;
 declare function proxify<T>(obj: T): Proxify<T>;
 interface Shape {
     name: string;

tests/baselines/reference/mappedTypes2.symbols

@@ -126,25 +126,25 @@ declare function pick<T, K extends keyof T>(obj: T, ...keys: K[]): Pick<T, K>;
 >T : Symbol(T, Decl(mappedTypes2.ts, 27, 22))
 >K : Symbol(K, Decl(mappedTypes2.ts, 27, 24))
 
-declare function mapObject<K extends string | number, T, U>(obj: Record<K, T>, f: (x: T) => U): Record<K, U>;
+declare function mapObject<K extends string, T, U>(obj: Record<K, T>, f: (x: T) => U): Record<K, U>;
 >mapObject : Symbol(mapObject, Decl(mappedTypes2.ts, 27, 78))
 >K : Symbol(K, Decl(mappedTypes2.ts, 28, 27))
->T : Symbol(T, Decl(mappedTypes2.ts, 28, 53))
->U : Symbol(U, Decl(mappedTypes2.ts, 28, 56))
->obj : Symbol(obj, Decl(mappedTypes2.ts, 28, 60))
+>T : Symbol(T, Decl(mappedTypes2.ts, 28, 44))
+>U : Symbol(U, Decl(mappedTypes2.ts, 28, 47))
+>obj : Symbol(obj, Decl(mappedTypes2.ts, 28, 51))
 >Record : Symbol(Record, Decl(lib.d.ts, --, --))
 >K : Symbol(K, Decl(mappedTypes2.ts, 28, 27))
->T : Symbol(T, Decl(mappedTypes2.ts, 28, 53))
->f : Symbol(f, Decl(mappedTypes2.ts, 28, 78))
->x : Symbol(x, Decl(mappedTypes2.ts, 28, 83))
->T : Symbol(T, Decl(mappedTypes2.ts, 28, 53))
->U : Symbol(U, Decl(mappedTypes2.ts, 28, 56))
+>T : Symbol(T, Decl(mappedTypes2.ts, 28, 44))
+>f : Symbol(f, Decl(mappedTypes2.ts, 28, 69))
+>x : Symbol(x, Decl(mappedTypes2.ts, 28, 74))
+>T : Symbol(T, Decl(mappedTypes2.ts, 28, 44))
+>U : Symbol(U, Decl(mappedTypes2.ts, 28, 47))
 >Record : Symbol(Record, Decl(lib.d.ts, --, --))
 >K : Symbol(K, Decl(mappedTypes2.ts, 28, 27))
->U : Symbol(U, Decl(mappedTypes2.ts, 28, 56))
+>U : Symbol(U, Decl(mappedTypes2.ts, 28, 47))
 
 declare function proxify<T>(obj: T): Proxify<T>;
->proxify : Symbol(proxify, Decl(mappedTypes2.ts, 28, 109))
+>proxify : Symbol(proxify, Decl(mappedTypes2.ts, 28, 100))
 >T : Symbol(T, Decl(mappedTypes2.ts, 29, 25))
 >obj : Symbol(obj, Decl(mappedTypes2.ts, 29, 28))
 >T : Symbol(T, Decl(mappedTypes2.ts, 29, 25))
@@ -295,7 +295,7 @@ function f5(shape: Shape) {
 
     const p = proxify(shape);
 >p : Symbol(p, Decl(mappedTypes2.ts, 79, 9))
->proxify : Symbol(proxify, Decl(mappedTypes2.ts, 28, 109))
+>proxify : Symbol(proxify, Decl(mappedTypes2.ts, 28, 100))
 >shape : Symbol(shape, Decl(mappedTypes2.ts, 78, 12))
 
     let name = p.name.get();

tests/baselines/reference/mappedTypes2.types

@@ -126,8 +126,8 @@ declare function pick<T, K extends keyof T>(obj: T, ...keys: K[]): Pick<T, K>;
 >T : T
 >K : K
 
-declare function mapObject<K extends string | number, T, U>(obj: Record<K, T>, f: (x: T) => U): Record<K, U>;
->mapObject : <K extends string | number, T, U>(obj: Record<K, T>, f: (x: T) => U) => Record<K, U>
+declare function mapObject<K extends string, T, U>(obj: Record<K, T>, f: (x: T) => U): Record<K, U>;
+>mapObject : <K extends string, T, U>(obj: Record<K, T>, f: (x: T) => U) => Record<K, U>
 >K : K
 >T : T
 >U : U
@@ -297,7 +297,7 @@ function f4() {
     const lengths = mapObject(rec, s => s.length);  // { foo: number, bar: number, baz: number }
 >lengths : Record<"foo" | "bar" | "baz", number>
 >mapObject(rec, s => s.length) : Record<"foo" | "bar" | "baz", number>
->mapObject : <K extends string | number, T, U>(obj: Record<K, T>, f: (x: T) => U) => Record<K, U>
+>mapObject : <K extends string, T, U>(obj: Record<K, T>, f: (x: T) => U) => Record<K, U>
 >rec : { foo: string; bar: string; baz: string; }
 >s => s.length : (s: string) => number
 >s : string

tests/baselines/reference/newWithSpread.js

@@ -107,7 +107,7 @@ function f(x, y) {
 function f2() {
     var x = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        x[_i - 0] = arguments[_i];
+        x[_i] = arguments[_i];
     }
 }
 var B = (function () {

tests/baselines/reference/newWithSpreadES5.js

@@ -106,7 +106,7 @@ function f(x, y) {
 function f2() {
     var x = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        x[_i - 0] = arguments[_i];
+        x[_i] = arguments[_i];
     }
 }
 var B = (function () {

tests/baselines/reference/noImplicitAnyParametersInBareFunctions.js

@@ -59,7 +59,7 @@ function f5(x, y, z) { }
 function f6() {
     var r = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        r[_i - 0] = arguments[_i];
+        r[_i] = arguments[_i];
     }
 }
 // Implicit-'any'/'any[]' errors for x, r.
@@ -82,7 +82,7 @@ var f12 = function (x, y, z) { return ""; };
 var f13 = function () {
     var r = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        r[_i - 0] = arguments[_i];
+        r[_i] = arguments[_i];
     }
     return "";
 };

tests/baselines/reference/noImplicitAnyParametersInClass.js

@@ -107,7 +107,7 @@ var C = (function () {
         this.pub_f13 = function () {
             var r = [];
             for (var _i = 0; _i < arguments.length; _i++) {
-                r[_i - 0] = arguments[_i];
+                r[_i] = arguments[_i];
             }
             return "";
         };
@@ -131,7 +131,7 @@ var C = (function () {
         this.priv_f13 = function () {
             var r = [];
             for (var _i = 0; _i < arguments.length; _i++) {
-                r[_i - 0] = arguments[_i];
+                r[_i] = arguments[_i];
             }
             return "";
         };
@@ -158,7 +158,7 @@ var C = (function () {
     C.prototype.pub_f6 = function () {
         var r = [];
         for (var _i = 0; _i < arguments.length; _i++) {
-            r[_i - 0] = arguments[_i];
+            r[_i] = arguments[_i];
         }
     };
     // Implicit-'any'/'any[]' errors for x, r.
@@ -184,7 +184,7 @@ var C = (function () {
     C.prototype.priv_f6 = function () {
         var r = [];
         for (var _i = 0; _i < arguments.length; _i++) {
-            r[_i - 0] = arguments[_i];
+            r[_i] = arguments[_i];
         }
     };
     // Implicit-'any'/'any[]' errors for x, r.

tests/baselines/reference/noImplicitAnyParametersInModule.js

@@ -63,7 +63,7 @@ var M;
     function m_f6() {
         var r = [];
         for (var _i = 0; _i < arguments.length; _i++) {
-            r[_i - 0] = arguments[_i];
+            r[_i] = arguments[_i];
         }
     }
     // Implicit-'any'/'any[]' errors for x and r.
@@ -86,7 +86,7 @@ var M;
     var m_f13 = function () {
         var r = [];
         for (var _i = 0; _i < arguments.length; _i++) {
-            r[_i - 0] = arguments[_i];
+            r[_i] = arguments[_i];
         }
         return "";
     };

tests/baselines/reference/nonArrayRestArgs.js

@@ -8,7 +8,7 @@ function foo(...rest: number) { // error
 function foo() {
     var rest = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        rest[_i - 0] = arguments[_i];
+        rest[_i] = arguments[_i];
     }
     var x = rest[0];
     return x;

tests/baselines/reference/optionalBindingParametersInOverloads1.js

@@ -13,7 +13,7 @@ foo([false, 0, ""]);
 function foo() {
     var rest = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        rest[_i - 0] = arguments[_i];
+        rest[_i] = arguments[_i];
     }
 }
 foo(["", 0, false]);

tests/baselines/reference/optionalBindingParametersInOverloads2.js

@@ -13,7 +13,7 @@ foo({ x: false, y: 0, z: "" });
 function foo() {
     var rest = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        rest[_i - 0] = arguments[_i];
+        rest[_i] = arguments[_i];
     }
 }
 foo({ x: "", y: 0, z: false });

tests/baselines/reference/overloadGenericFunctionWithRestArgs.js

@@ -24,7 +24,7 @@ var A = (function () {
 function Choice() {
     var v_args = [];
     for (var _i = 0; _i < arguments.length; _i++) {
-        v_args[_i - 0] = arguments[_i];
+        v_args[_i] = arguments[_i];
     }
     return new A();
 }