Merge branch 'master' into builderApi

.npmignore

@@ -18,4 +18,5 @@ Jakefile.js
 .settings/
 .travis.yml
 .vscode/
-test.config
+test.config
+package-lock.json

issue_template.md

@@ -1,10 +1,34 @@
-<!-- BUGS: Please use this template. -->
-<!-- QUESTIONS: This is not a general support forum! Ask Qs at http://stackoverflow.com/questions/tagged/typescript -->
-<!-- SUGGESTIONS: See https://github.com/Microsoft/TypeScript-wiki/blob/master/Writing-Good-Design-Proposals.md -->
+<!-- 🚨 STOP 🚨 𝗦𝗧𝗢𝗣 🚨 𝑺𝑻𝑶𝑷 🚨 -->
+<!--
+Half of all issues filed here are duplicates, answered in the FAQ, or not appropriate for the bug tracker.
+
+Please help us by doing the following steps before logging an issue:
+  * Search: https://github.com/Microsoft/TypeScript/search?type=Issues
+  * Read the CONTRIBUTING guidelines: https://github.com/Microsoft/TypeScript/blob/master/CONTRIBUTING.md
+  * Read the FAQ: https://github.com/Microsoft/TypeScript/wiki/FAQ
+-->
+
+<!-- If you have a QUESTION:
+   THIS IS NOT A FORUM FOR QUESTIONS.
+   Ask questions at http://stackoverflow.com/questions/tagged/typescript
+    or https://gitter.im/Microsoft/TypeScript
+-->
+
+<!-- If you have a SUGGESTION:
+  Most suggestion reports are duplicates, please search extra hard before logging a new suggestion.
+  See https://github.com/Microsoft/TypeScript-wiki/blob/master/Writing-Good-Design-Proposals.md
+-->
+
+<!-- If you have a BUG:
+  Please fill in the *entire* template below.
+-->
 
 <!-- Please try to reproduce the issue with `typescript@next`. It may have already been fixed. -->
 **TypeScript Version:**  2.7.0-dev.201xxxxx
 
+<!-- Search terms you tried before logging this (so others can find this issue more easily) -->
+**Search Terms:** 
+
 **Code**
 
 ```ts
@@ -16,4 +40,6 @@
 
 **Actual behavior:**
 
-**Related:**
+**Playground Link:** <!-- A link to a TypeScript Playground "Share" link which demonstrates this behavior --> 
+
+**Related Issues:**

src/compiler/checker.ts

@@ -6564,7 +6564,7 @@ namespace ts {
             // b) It references `arguments` somewhere
             const lastParam = lastOrUndefined(declaration.parameters);
             const lastParamTags = lastParam && getJSDocParameterTags(lastParam);
-            const lastParamVariadicType = lastParamTags && firstDefined(lastParamTags, p =>
+            const lastParamVariadicType = firstDefined(lastParamTags, p =>
                 p.typeExpression && isJSDocVariadicType(p.typeExpression.type) ? p.typeExpression.type : undefined);
             if (!lastParamVariadicType && !containsArgumentsReference(declaration)) {
                 return false;
@@ -9639,7 +9639,7 @@ namespace ts {
                 }
                 else if (target.flags & TypeFlags.IndexedAccess) {
                     // A type S is related to a type T[K] if S is related to A[K], where K is string-like and
-                    // A is the apparent type of T.
+                    // A is the constraint of T.
                     const constraint = getConstraintOfIndexedAccess(<IndexedAccessType>target);
                     if (constraint) {
                         if (result = isRelatedTo(source, constraint, reportErrors)) {
@@ -9675,7 +9675,7 @@ namespace ts {
                 }
                 else if (source.flags & TypeFlags.IndexedAccess) {
                     // A type S[K] is related to a type T if A[K] is related to T, where K is string-like and
-                    // A is the apparent type of S.
+                    // A is the constraint of S.
                     const constraint = getConstraintOfIndexedAccess(<IndexedAccessType>source);
                     if (constraint) {
                         if (result = isRelatedTo(constraint, target, reportErrors)) {
@@ -9683,10 +9683,11 @@ namespace ts {
                             return result;
                         }
                     }
-                    else if (target.flags & TypeFlags.IndexedAccess && (<IndexedAccessType>source).indexType === (<IndexedAccessType>target).indexType) {
-                        // if we have indexed access types with identical index types, see if relationship holds for
-                        // the two object types.
+                    else if (target.flags & TypeFlags.IndexedAccess) {
                         if (result = isRelatedTo((<IndexedAccessType>source).objectType, (<IndexedAccessType>target).objectType, reportErrors)) {
+                            result &= isRelatedTo((<IndexedAccessType>source).indexType, (<IndexedAccessType>target).indexType, reportErrors);
+                        }
+                        if (result) {
                             errorInfo = saveErrorInfo;
                             return result;
                         }
@@ -10967,7 +10968,7 @@ namespace ts {
             return type === typeParameter || type.flags & TypeFlags.UnionOrIntersection && forEach((<UnionOrIntersectionType>type).types, t => isTypeParameterAtTopLevel(t, typeParameter));
         }
 
-        /** Create an object with properties named in the string literal type. Every property has type `{}` */
+        /** Create an object with properties named in the string literal type. Every property has type `any` */
         function createEmptyObjectTypeFromStringLiteral(type: Type) {
             const members = createSymbolTable();
             forEachType(type, t => {
@@ -10976,7 +10977,7 @@ namespace ts {
                 }
                 const name = escapeLeadingUnderscores((t as StringLiteralType).value);
                 const literalProp = createSymbol(SymbolFlags.Property, name);
-                literalProp.type = emptyObjectType;
+                literalProp.type = anyType;
                 if (t.symbol) {
                     literalProp.declarations = t.symbol.declarations;
                     literalProp.valueDeclaration = t.symbol.valueDeclaration;
@@ -11031,7 +11032,9 @@ namespace ts {
             const templateType = getTemplateTypeFromMappedType(target);
             const inference = createInferenceInfo(typeParameter);
             inferTypes([inference], sourceType, templateType);
-            return inference.candidates ? getUnionType(inference.candidates, UnionReduction.Subtype) : emptyObjectType;
+            return inference.candidates ? getUnionType(inference.candidates, UnionReduction.Subtype) :
+                inference.contraCandidates ? getCommonSubtype(inference.contraCandidates) :
+                emptyObjectType;
         }
 
         function getUnmatchedProperty(source: Type, target: Type, requireOptionalProperties: boolean) {
@@ -18377,6 +18380,9 @@ namespace ts {
 
         function checkObjectLiteralAssignment(node: ObjectLiteralExpression, sourceType: Type): Type {
             const properties = node.properties;
+            if (strictNullChecks && properties.length === 0) {
+                return checkNonNullType(sourceType, node);
+            }
             for (const p of properties) {
                 checkObjectLiteralDestructuringPropertyAssignment(sourceType, p, properties);
             }
@@ -21446,7 +21452,13 @@ namespace ts {
             if (isBindingPattern(node.name)) {
                 // Don't validate for-in initializer as it is already an error
                 if (node.initializer && node.parent.parent.kind !== SyntaxKind.ForInStatement) {
-                    checkTypeAssignableTo(checkExpressionCached(node.initializer), getWidenedTypeForVariableLikeDeclaration(node), node, /*headMessage*/ undefined);
+                    const initializerType = checkExpressionCached(node.initializer);
+                    if (strictNullChecks && node.name.elements.length === 0) {
+                        checkNonNullType(initializerType, node);
+                    }
+                    else {
+                        checkTypeAssignableTo(initializerType, getWidenedTypeForVariableLikeDeclaration(node), node, /*headMessage*/ undefined);
+                    }
                     checkParameterInitializer(node);
                 }
                 return;
@@ -26196,7 +26208,7 @@ namespace ts {
         function checkGrammarBindingElement(node: BindingElement) {
             if (node.dotDotDotToken) {
                 const elements = (<BindingPattern>node.parent).elements;
-                if (node !== lastOrUndefined(elements)) {
+                if (node !== last(elements)) {
                     return grammarErrorOnNode(node, Diagnostics.A_rest_element_must_be_last_in_a_destructuring_pattern);
                 }
 
@@ -26204,6 +26216,10 @@ namespace ts {
                     return grammarErrorOnNode(node.name, Diagnostics.A_rest_element_cannot_contain_a_binding_pattern);
                 }
 
+                if (node.propertyName) {
+                    return grammarErrorOnNode(node.name, Diagnostics.A_rest_element_cannot_have_a_property_name);
+                }
+
                 if (node.initializer) {
                     // Error on equals token which immediately precedes the initializer
                     return grammarErrorAtPos(node, node.initializer.pos - 1, 1, Diagnostics.A_rest_element_cannot_have_an_initializer);

src/compiler/core.ts

@@ -183,6 +183,10 @@ namespace ts {
 
     /** Like `forEach`, but suitable for use with numbers and strings (which may be falsy). */
     export function firstDefined<T, U>(array: ReadonlyArray<T> | undefined, callback: (element: T, index: number) => U | undefined): U | undefined {
+        if (array === undefined) {
+            return undefined;
+        }
+
         for (let i = 0; i < array.length; i++) {
             const result = callback(array[i], i);
             if (result !== undefined) {

src/compiler/diagnosticMessages.json

@@ -1976,6 +1976,10 @@
         "category": "Error",
         "code": 2565
     },
+    "A rest element cannot have a property name.": {
+        "category": "Error",
+        "code": 2566
+    },
     "JSX element attributes type '{0}' may not be a union type.": {
         "category": "Error",
         "code": 2600
@@ -3893,10 +3897,6 @@
         "category": "Message",
         "code": 95002
     },
-    "Extract symbol": {
-        "category": "Message",
-        "code": 95003
-    },
     "Extract to {0} in {1}": {
         "category": "Message",
         "code": 95004

src/compiler/emitter.ts

@@ -1268,12 +1268,12 @@ namespace ts {
         }
 
         function emitBindingElement(node: BindingElement) {
+            emitIfPresent(node.dotDotDotToken);
             if (node.propertyName) {
                 emit(node.propertyName);
                 writePunctuation(":");
                 writeSpace();
             }
-            emitIfPresent(node.dotDotDotToken);
             emit(node.name);
             emitInitializer(node.initializer);
         }

src/compiler/parser.ts

@@ -126,8 +126,8 @@ namespace ts {
             case SyntaxKind.BindingElement:
                 return visitNodes(cbNode, cbNodes, node.decorators) ||
                     visitNodes(cbNode, cbNodes, node.modifiers) ||
-                    visitNode(cbNode, (<BindingElement>node).propertyName) ||
                     visitNode(cbNode, (<BindingElement>node).dotDotDotToken) ||
+                    visitNode(cbNode, (<BindingElement>node).propertyName) ||
                     visitNode(cbNode, (<BindingElement>node).name) ||
                     visitNode(cbNode, (<BindingElement>node).initializer);
             case SyntaxKind.FunctionType:
@@ -6830,7 +6830,7 @@ namespace ts {
                 }
 
                 function parseTemplateTag(atToken: AtToken, tagName: Identifier): JSDocTemplateTag | undefined {
-                    if (forEach(tags, t => t.kind === SyntaxKind.JSDocTemplateTag)) {
+                    if (some(tags, isJSDocTemplateTag)) {
                         parseErrorAtPosition(tagName.pos, scanner.getTokenPos() - tagName.pos, Diagnostics._0_tag_already_specified, tagName.escapedText);
                     }
 
@@ -6839,14 +6839,14 @@ namespace ts {
                     const typeParametersPos = getNodePos();
 
                     while (true) {
-                        const name = parseJSDocIdentifierName();
+                        const typeParameter = <TypeParameterDeclaration>createNode(SyntaxKind.TypeParameter);
+                        const name = parseJSDocIdentifierNameWithOptionalBraces();
                         skipWhitespace();
                         if (!name) {
                             parseErrorAtPosition(scanner.getStartPos(), 0, Diagnostics.Identifier_expected);
                             return undefined;
                         }
 
-                        const typeParameter = <TypeParameterDeclaration>createNode(SyntaxKind.TypeParameter, name.pos);
                         typeParameter.name = name;
                         finishNode(typeParameter);
 
@@ -6869,6 +6869,15 @@ namespace ts {
                     return result;
                 }
 
+                function parseJSDocIdentifierNameWithOptionalBraces(): Identifier | undefined {
+                    const parsedBrace = parseOptional(SyntaxKind.OpenBraceToken);
+                    const res = parseJSDocIdentifierName();
+                    if (parsedBrace) {
+                        parseExpected(SyntaxKind.CloseBraceToken);
+                    }
+                    return res;
+                }
+
                 function nextJSDocToken(): JsDocSyntaxKind {
                     return currentToken = scanner.scanJSDocToken();
                 }

src/compiler/resolutionCache.ts

@@ -474,11 +474,6 @@ namespace ts {
                     cachedDirectoryStructureHost.addOrDeleteFileOrDirectory(fileOrDirectory, fileOrDirectoryPath);
                 }
 
-                // Ignore emits from the program
-                if (isEmittedFileOfProgram(resolutionHost.getCurrentProgram(), fileOrDirectory)) {
-                    return;
-                }
-
                 // If the files are added to project root or node_modules directory, always run through the invalidation process
                 // Otherwise run through invalidation only if adding to the immediate directory
                 if (!allFilesHaveInvalidatedResolution &&
@@ -582,6 +577,10 @@ namespace ts {
                     if (!isPathWithDefaultFailedLookupExtension(fileOrDirectoryPath) && !customFailedLookupPaths.has(fileOrDirectoryPath)) {
                         return false;
                     }
+                    // Ignore emits from the program
+                    if (isEmittedFileOfProgram(resolutionHost.getCurrentProgram(), fileOrDirectoryPath)) {
+                        return false;
+                    }
                     // Resolution need to be invalidated if failed lookup location is same as the file or directory getting created
                     isChangedFailedLookupLocation = location => resolutionHost.toPath(location) === fileOrDirectoryPath;
                 }

src/compiler/utilities.ts

@@ -2029,7 +2029,13 @@ namespace ts {
         return token !== undefined && isNonContextualKeyword(token);
     }
 
-    export function isTrivia(token: SyntaxKind) {
+    export type TriviaKind = SyntaxKind.SingleLineCommentTrivia
+        | SyntaxKind.MultiLineCommentTrivia
+        | SyntaxKind.NewLineTrivia
+        | SyntaxKind.WhitespaceTrivia
+        | SyntaxKind.ShebangTrivia
+        | SyntaxKind.ConflictMarkerTrivia;
+    export function isTrivia(token: SyntaxKind): token is TriviaKind {
         return SyntaxKind.FirstTriviaToken <= token && token <= SyntaxKind.LastTriviaToken;
     }
 

src/harness/externalCompileRunner.ts

@@ -33,12 +33,15 @@ abstract class ExternalCompileRunnerBase extends RunnerBase {
         });
     }
     private runTest(directoryName: string) {
-        describe(directoryName, () => {
+        // tslint:disable-next-line:no-this-assignment
+        const cls = this;
+        const timeout = 600_000; // 10 minutes
+        describe(directoryName, function(this: Mocha.ISuiteCallbackContext) {
+            this.timeout(timeout);
             const cp = require("child_process");
 
             it("should build successfully", () => {
-                let cwd = path.join(__dirname, "../../", this.testDir, directoryName);
-                const timeout = 600000; // 600s = 10 minutes
+                let cwd = path.join(__dirname, "../../", cls.testDir, directoryName);
                 const stdio = isWorker ? "pipe" : "inherit";
                 let types: string[];
                 if (fs.existsSync(path.join(cwd, "test.json"))) {
@@ -61,9 +64,9 @@ abstract class ExternalCompileRunnerBase extends RunnerBase {
                         fs.unlinkSync(path.join(cwd, "package-lock.json"));
                     }
                     if (fs.existsSync(path.join(cwd, "node_modules"))) {
-                        require("del").sync(path.join(cwd, "node_modules"));
+                        require("del").sync(path.join(cwd, "node_modules"), { force: true });
                     }
-                    const install = cp.spawnSync(`npm`, ["i"], { cwd, timeout, shell: true, stdio });
+                    const install = cp.spawnSync(`npm`, ["i"], { cwd, timeout: timeout / 2, shell: true, stdio }); // NPM shouldn't take the entire timeout - if it takes a long time, it should be terminated and we should log the failure
                     if (install.status !== 0) throw new Error(`NPM Install for ${directoryName} failed: ${install.stderr.toString()}`);
                 }
                 const args = [path.join(__dirname, "tsc.js")];
@@ -71,8 +74,8 @@ abstract class ExternalCompileRunnerBase extends RunnerBase {
                     args.push("--types", types.join(","));
                 }
                 args.push("--noEmit");
-                Harness.Baseline.runBaseline(`${this.kind()}/${directoryName}.log`, () => {
-                    return this.report(cp.spawnSync(`node`, args, { cwd, timeout, shell: true }), cwd);
+                Harness.Baseline.runBaseline(`${cls.kind()}/${directoryName}.log`, () => {
+                    return cls.report(cp.spawnSync(`node`, args, { cwd, timeout, shell: true }), cwd);
                 });
             });
         });

src/harness/fourslash.ts

@@ -1102,20 +1102,30 @@ namespace FourSlash {
         }
 
         public verifyReferenceGroups(startRanges: Range | Range[], parts: FourSlashInterface.ReferenceGroup[]): void {
-            const fullExpected = ts.map(parts, ({ definition, ranges }) => ({ definition, ranges: ranges.map(rangeToReferenceEntry) }));
+            interface ReferenceGroupJson {
+                definition: string | { text: string, range: ts.TextSpan };
+                references: ts.ReferenceEntry[];
+            }
+            const fullExpected = ts.map<FourSlashInterface.ReferenceGroup, ReferenceGroupJson>(parts, ({ definition, ranges }) => ({
+                definition: typeof definition === "string" ? definition : { ...definition, range: textSpanFromRange(definition.range) },
+                references: ranges.map(rangeToReferenceEntry),
+            }));
 
             for (const startRange of toArray(startRanges)) {
                 this.goToRangeStart(startRange);
-                const fullActual = ts.map(this.findReferencesAtCaret(), ({ definition, references }) => ({
-                    definition: definition.displayParts.map(d => d.text).join(""),
-                    ranges: references
-                }));
+                const fullActual = ts.map<ts.ReferencedSymbol, ReferenceGroupJson>(this.findReferencesAtCaret(), ({ definition, references }, i) => {
+                    const text = definition.displayParts.map(d => d.text).join("");
+                    return {
+                        definition: typeof fullExpected[i].definition === "string" ? text : { text, range: definition.textSpan },
+                        references,
+                    };
+                });
                 this.assertObjectsEqual(fullActual, fullExpected);
             }
 
             function rangeToReferenceEntry(r: Range): ts.ReferenceEntry {
                 const { isWriteAccess, isDefinition, isInString } = (r.marker && r.marker.data) || { isWriteAccess: false, isDefinition: false, isInString: undefined };
-                const result: ts.ReferenceEntry = { fileName: r.fileName, textSpan: { start: r.start, length: r.end - r.start }, isWriteAccess: !!isWriteAccess, isDefinition: !!isDefinition };
+                const result: ts.ReferenceEntry = { fileName: r.fileName, textSpan: textSpanFromRange(r), isWriteAccess: !!isWriteAccess, isDefinition: !!isDefinition };
                 if (isInString !== undefined) {
                     result.isInString = isInString;
                 }
@@ -1139,7 +1149,7 @@ namespace FourSlash {
             }
         }
 
-        public verifySingleReferenceGroup(definition: string, ranges?: Range[]) {
+        public verifySingleReferenceGroup(definition: FourSlashInterface.ReferenceGroupDefinition, ranges?: Range[]) {
             ranges = ranges || this.getRanges();
             this.verifyReferenceGroups(ranges, [{ definition, ranges }]);
         }
@@ -1305,8 +1315,13 @@ Actual: ${stringify(fullActual)}`);
         }
 
         public verifyRangesAreRenameLocations(options?: Range[] | { findInStrings?: boolean, findInComments?: boolean, ranges?: Range[] }) {
-            const ranges = ts.isArray(options) ? options : options && options.ranges || this.getRanges();
-            this.verifyRenameLocations(ranges, { ranges, ...options });
+            if (ts.isArray(options)) {
+                this.verifyRenameLocations(options, options);
+            }
+            else {
+                const ranges = options && options.ranges || this.getRanges();
+                this.verifyRenameLocations(ranges, { ranges, ...options });
+            }
         }
 
         public verifyRenameLocations(startRanges: Range | Range[], options: Range[] | { findInStrings?: boolean, findInComments?: boolean, ranges: Range[] }) {
@@ -2568,9 +2583,7 @@ Actual: ${stringify(fullActual)}`);
             const originalContent = scriptInfo.content;
             for (const codeFix of codeFixes) {
                 this.applyEdits(codeFix.changes[0].fileName, codeFix.changes[0].textChanges, /*isFormattingEdit*/ false);
-                let text = this.rangeText(ranges[0]);
-                // TODO:GH#18445 (remove this line to see errors in many `importNameCodeFix` tests)
-                text = text.replace(/\r\n/g, "\n");
+                const text = this.rangeText(ranges[0]);
                 actualTextArray.push(text);
                 scriptInfo.updateContent(originalContent);
             }
@@ -4077,7 +4090,7 @@ namespace FourSlashInterface {
             this.state.verifyNoReferences(markerNameOrRange);
         }
 
-        public singleReferenceGroup(definition: string, ranges?: FourSlash.Range[]) {
+        public singleReferenceGroup(definition: ReferenceGroupDefinition, ranges?: FourSlash.Range[]) {
             this.state.verifySingleReferenceGroup(definition, ranges);
         }
 
@@ -4589,10 +4602,12 @@ namespace FourSlashInterface {
     }
 
     export interface ReferenceGroup {
-        definition: string;
+        definition: ReferenceGroupDefinition;
         ranges: FourSlash.Range[];
     }
 
+    export type ReferenceGroupDefinition = string | { text: string, range: FourSlash.Range };
+
     export interface ApplyRefactorOptions {
         refactorName: string;
         actionName: string;

src/harness/unittests/extractTestHelpers.ts

@@ -121,7 +121,6 @@ namespace ts {
             const sourceFile = program.getSourceFile(path);
             const context: RefactorContext = {
                 cancellationToken: { throwIfCancellationRequested: noop, isCancellationRequested: returnFalse },
-                newLineCharacter,
                 program,
                 file: sourceFile,
                 startPosition: selectionRange.start,
@@ -185,7 +184,6 @@ namespace ts {
             const sourceFile = program.getSourceFile(f.path);
             const context: RefactorContext = {
                 cancellationToken: { throwIfCancellationRequested: noop, isCancellationRequested: returnFalse },
-                newLineCharacter,
                 program,
                 file: sourceFile,
                 startPosition: selectionRange.start,

src/loc/lcl/chs/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -888,6 +888,9 @@
       <Item ItemId=";Add_async_modifier_to_containing_function_90029" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Add async modifier to containing function]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[将异步修饰符添加到包含函数]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>
@@ -4620,6 +4623,9 @@
       <Item ItemId=";Mapped_object_type_implicitly_has_an_any_template_type_7039" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Mapped object type implicitly has an 'any' template type.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[映射的对象类型隐式地含有 "any" 模板类型。]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>

src/loc/lcl/cht/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -888,6 +888,9 @@
       <Item ItemId=";Add_async_modifier_to_containing_function_90029" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Add async modifier to containing function]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[將 async 修飾詞新增至包含的函式]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>
@@ -4620,6 +4623,9 @@
       <Item ItemId=";Mapped_object_type_implicitly_has_an_any_template_type_7039" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Mapped object type implicitly has an 'any' template type.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[對應的物件類型隱含具有 'any' 範本類型。]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>

src/loc/lcl/csy/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -897,6 +897,9 @@
       <Item ItemId=";Add_async_modifier_to_containing_function_90029" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Add async modifier to containing function]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[Přidat modifikátor async do obsahující funkce]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>
@@ -4629,6 +4632,9 @@
       <Item ItemId=";Mapped_object_type_implicitly_has_an_any_template_type_7039" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Mapped object type implicitly has an 'any' template type.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[Typu mapovaného objektu má implicitně typ šablony any.]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>

src/loc/lcl/deu/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -885,6 +885,9 @@
       <Item ItemId=";Add_async_modifier_to_containing_function_90029" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Add async modifier to containing function]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[Async-Modifizierer zur enthaltenden Funktion hinzufügen]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>
@@ -4617,6 +4620,9 @@
       <Item ItemId=";Mapped_object_type_implicitly_has_an_any_template_type_7039" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Mapped object type implicitly has an 'any' template type.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[Der zugeordnete Objekttyp weist implizit einen any-Vorlagentyp auf.]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>

src/loc/lcl/esn/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -897,6 +897,9 @@
       <Item ItemId=";Add_async_modifier_to_containing_function_90029" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Add async modifier to containing function]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[Agregar el modificador async a la función contenedora]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>
@@ -4629,6 +4632,9 @@
       <Item ItemId=";Mapped_object_type_implicitly_has_an_any_template_type_7039" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Mapped object type implicitly has an 'any' template type.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[El tipo de objeto asignado tiene implícitamente un tipo de plantilla "any".]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>

src/loc/lcl/fra/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -897,6 +897,9 @@
       <Item ItemId=";Add_async_modifier_to_containing_function_90029" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Add async modifier to containing function]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[Ajouter le modificateur async dans la fonction conteneur]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>
@@ -4629,6 +4632,9 @@
       <Item ItemId=";Mapped_object_type_implicitly_has_an_any_template_type_7039" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Mapped object type implicitly has an 'any' template type.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[Le type d'objet mappé a implicitement un type de modèle 'any'.]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>

src/loc/lcl/ita/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -888,6 +888,9 @@
       <Item ItemId=";Add_async_modifier_to_containing_function_90029" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Add async modifier to containing function]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[Aggiungere il modificatore async alla funzione contenitore]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>
@@ -4620,6 +4623,9 @@
       <Item ItemId=";Mapped_object_type_implicitly_has_an_any_template_type_7039" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Mapped object type implicitly has an 'any' template type.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[Il tipo di oggetto con mapping contiene implicitamente un tipo di modello 'any'.]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>

src/loc/lcl/jpn/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -888,6 +888,9 @@
       <Item ItemId=";Add_async_modifier_to_containing_function_90029" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Add async modifier to containing function]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[含まれている関数に async 修飾子を追加します]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>
@@ -4620,6 +4623,9 @@
       <Item ItemId=";Mapped_object_type_implicitly_has_an_any_template_type_7039" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Mapped object type implicitly has an 'any' template type.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[マップされたオブジェクト型のテンプレートの型は暗黙的に 'any' になります。]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>

src/loc/lcl/kor/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -888,6 +888,9 @@
       <Item ItemId=";Add_async_modifier_to_containing_function_90029" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Add async modifier to containing function]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[포함된 함수에 async 한정자 추가]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>
@@ -4620,6 +4623,9 @@
       <Item ItemId=";Mapped_object_type_implicitly_has_an_any_template_type_7039" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Mapped object type implicitly has an 'any' template type.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[매핑된 개체 형식에는 'any' 템플릿 형식이 암시적으로 포함됩니다.]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>

src/loc/lcl/plk/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -878,6 +878,9 @@
       <Item ItemId=";Add_async_modifier_to_containing_function_90029" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Add async modifier to containing function]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[Dodaj modyfikator asynchroniczny do funkcji zawierającej]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>
@@ -4610,6 +4613,9 @@
       <Item ItemId=";Mapped_object_type_implicitly_has_an_any_template_type_7039" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Mapped object type implicitly has an 'any' template type.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[Zmapowany typ obiektu niejawnie ma typ szablonu „any”.]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>

src/loc/lcl/ptb/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -878,6 +878,9 @@
       <Item ItemId=";Add_async_modifier_to_containing_function_90029" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Add async modifier to containing function]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[Adicione o modificador assíncrono que contém a função]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>
@@ -4610,6 +4613,9 @@
       <Item ItemId=";Mapped_object_type_implicitly_has_an_any_template_type_7039" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Mapped object type implicitly has an 'any' template type.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[O tipo de objeto mapeado implicitamente tem um tipo de modelo 'any'.]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>

src/loc/lcl/rus/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -887,6 +887,9 @@
       <Item ItemId=";Add_async_modifier_to_containing_function_90029" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Add async modifier to containing function]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[Добавьте модификатор async в содержащую функцию]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>
@@ -4619,6 +4622,9 @@
       <Item ItemId=";Mapped_object_type_implicitly_has_an_any_template_type_7039" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Mapped object type implicitly has an 'any' template type.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[Сопоставленный объект неявно имеет тип шаблона "любой".]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>

src/loc/lcl/trk/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -881,6 +881,9 @@
       <Item ItemId=";Add_async_modifier_to_containing_function_90029" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Add async modifier to containing function]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[İçeren işleve zaman uyumsuz değiştirici ekle]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>
@@ -4613,6 +4616,9 @@
       <Item ItemId=";Mapped_object_type_implicitly_has_an_any_template_type_7039" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[Mapped object type implicitly has an 'any' template type.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[Eşleştirilmiş nesne türü örtük olarak 'any' şablon türüne sahip.]]></Val>
+          </Tgt>
         </Str>
         <Disp Icon="Str" />
       </Item>

src/server/editorServices.ts

@@ -1810,9 +1810,9 @@ namespace ts.server {
             let info = this.getScriptInfoForPath(path);
             if (!info) {
                 const isDynamic = isDynamicFileName(fileName);
-                Debug.assert(isRootedDiskPath(fileName) || isDynamic || openedByClient, "Script info with non-dynamic relative file name can only be open script info");
-                Debug.assert(!isRootedDiskPath(fileName) || this.currentDirectory === currentDirectory || !this.openFilesWithNonRootedDiskPath.has(this.toCanonicalFileName(fileName)), "Open script files with non rooted disk path opened with current directory context cannot have same canonical names");
-                Debug.assert(!isDynamic || this.currentDirectory === currentDirectory, "Dynamic files must always have current directory context since containing external project name will always match the script info name.");
+                Debug.assert(isRootedDiskPath(fileName) || isDynamic || openedByClient, "", () => `${JSON.stringify({ fileName, currentDirectory, hostCurrentDirectory: this.currentDirectory, openKeys: arrayFrom(this.openFilesWithNonRootedDiskPath.keys()) })}\nScript info with non-dynamic relative file name can only be open script info`);
+                Debug.assert(!isRootedDiskPath(fileName) || this.currentDirectory === currentDirectory || !this.openFilesWithNonRootedDiskPath.has(this.toCanonicalFileName(fileName)), "", () => `${JSON.stringify({ fileName, currentDirectory, hostCurrentDirectory: this.currentDirectory, openKeys: arrayFrom(this.openFilesWithNonRootedDiskPath.keys()) })}\nOpen script files with non rooted disk path opened with current directory context cannot have same canonical names`);
+                Debug.assert(!isDynamic || this.currentDirectory === currentDirectory, "", () => `${JSON.stringify({ fileName, currentDirectory, hostCurrentDirectory: this.currentDirectory, openKeys: arrayFrom(this.openFilesWithNonRootedDiskPath.keys()) })}\nDynamic files must always have current directory context since containing external project name will always match the script info name.`);
                 // If the file is not opened by client and the file doesnot exist on the disk, return
                 if (!openedByClient && !isDynamic && !(hostToQueryFileExistsOn || this.host).fileExists(fileName)) {
                     return;

src/server/session.ts

@@ -1665,9 +1665,9 @@ namespace ts.server {
             return { startPosition, endPosition };
         }
 
-        private mapCodeAction(project: Project, { description, changes: unmappedChanges, commands }: CodeAction): protocol.CodeAction {
+        private mapCodeAction(project: Project, { description, changes: unmappedChanges, commands, fixId }: CodeFixAction): protocol.CodeFixAction {
             const changes = unmappedChanges.map(change => this.mapTextChangesToCodeEditsUsingScriptinfo(change, project.getScriptInfoForNormalizedPath(toNormalizedPath(change.fileName))));
-            return { description, changes, commands };
+            return { description, changes, commands, fixId };
         }
 
         private mapTextChangesToCodeEdits(project: Project, textChanges: ReadonlyArray<FileTextChanges>): protocol.FileCodeEdits[] {

src/services/classifier.ts

@@ -619,37 +619,46 @@ namespace ts {
                     return start;
                 }
 
-                // Don't bother with newlines/whitespace.
-                if (kind === SyntaxKind.NewLineTrivia || kind === SyntaxKind.WhitespaceTrivia) {
-                    continue;
-                }
-
-                // Only bother with the trivia if it at least intersects the span of interest.
-                if (isComment(kind)) {
-                    classifyComment(token, kind, start, width);
-
-                    // Classifying a comment might cause us to reuse the trivia scanner
-                    // (because of jsdoc comments).  So after we classify the comment make
-                    // sure we set the scanner position back to where it needs to be.
-                    triviaScanner.setTextPos(end);
-                    continue;
-                }
-
-                if (kind === SyntaxKind.ConflictMarkerTrivia) {
-                    const text = sourceFile.text;
-                    const ch = text.charCodeAt(start);
-
-                    // for the <<<<<<< and >>>>>>> markers, we just add them in as comments
-                    // in the classification stream.
-                    if (ch === CharacterCodes.lessThan || ch === CharacterCodes.greaterThan) {
-                        pushClassification(start, width, ClassificationType.comment);
+                switch (kind) {
+                    case SyntaxKind.NewLineTrivia:
+                    case SyntaxKind.WhitespaceTrivia:
+                        // Don't bother with newlines/whitespace.
                         continue;
-                    }
 
-                    // for the ||||||| and ======== markers, add a comment for the first line,
-                    // and then lex all subsequent lines up until the end of the conflict marker.
-                    Debug.assert(ch === CharacterCodes.bar || ch === CharacterCodes.equals);
-                    classifyDisabledMergeCode(text, start, end);
+                    case SyntaxKind.SingleLineCommentTrivia:
+                    case SyntaxKind.MultiLineCommentTrivia:
+                        // Only bother with the trivia if it at least intersects the span of interest.
+                        classifyComment(token, kind, start, width);
+
+                        // Classifying a comment might cause us to reuse the trivia scanner
+                        // (because of jsdoc comments).  So after we classify the comment make
+                        // sure we set the scanner position back to where it needs to be.
+                        triviaScanner.setTextPos(end);
+                        continue;
+
+                    case SyntaxKind.ConflictMarkerTrivia:
+                        const text = sourceFile.text;
+                        const ch = text.charCodeAt(start);
+
+                        // for the <<<<<<< and >>>>>>> markers, we just add them in as comments
+                        // in the classification stream.
+                        if (ch === CharacterCodes.lessThan || ch === CharacterCodes.greaterThan) {
+                            pushClassification(start, width, ClassificationType.comment);
+                            continue;
+                        }
+
+                        // for the ||||||| and ======== markers, add a comment for the first line,
+                        // and then lex all subsequent lines up until the end of the conflict marker.
+                        Debug.assert(ch === CharacterCodes.bar || ch === CharacterCodes.equals);
+                        classifyDisabledMergeCode(text, start, end);
+                        break;
+
+                    case SyntaxKind.ShebangTrivia:
+                        // TODO: Maybe we should classify these.
+                        break;
+
+                    default:
+                        Debug.assertNever(kind);
                 }
             }
         }

src/services/codeFixProvider.ts

@@ -10,7 +10,6 @@ namespace ts {
     export interface CodeFixContextBase extends textChanges.TextChangesContext {
         sourceFile: SourceFile;
         program: Program;
-        host: LanguageServiceHost;
         cancellationToken: CancellationToken;
     }
 

src/services/codefixes/disableJsDiagnostics.ts

@@ -9,12 +9,14 @@ namespace ts.codefix {
     registerCodeFix({
         errorCodes,
         getCodeActions(context) {
-            const { sourceFile, program, newLineCharacter, span } = context;
+            const { sourceFile, program, span } = context;
 
             if (!isInJavaScriptFile(sourceFile) || !isCheckJsEnabledForFile(sourceFile, program.getCompilerOptions())) {
                 return undefined;
             }
 
+            const newLineCharacter = getNewLineOrDefaultFromHost(context.host, context.formatContext.options);
+
             return [{
                 description: getLocaleSpecificMessage(Diagnostics.Ignore_this_error_message),
                 changes: [createFileTextChanges(sourceFile.fileName, [getIgnoreCommentLocationForLocation(sourceFile, span.start, newLineCharacter)])],
@@ -36,7 +38,7 @@ namespace ts.codefix {
         fixIds: [fixId], // No point applying as a group, doing it once will fix all errors
         getAllCodeActions: context => codeFixAllWithTextChanges(context, errorCodes, (changes, err) => {
             if (err.start !== undefined) {
-                changes.push(getIgnoreCommentLocationForLocation(err.file!, err.start, context.newLineCharacter));
+                changes.push(getIgnoreCommentLocationForLocation(err.file!, err.start, getNewLineOrDefaultFromHost(context.host, context.formatContext.options)));
             }
         }),
     });

src/services/codefixes/fixAddMissingMember.ts

@@ -142,7 +142,7 @@ namespace ts.codefix {
         return typeNode || createKeywordTypeNode(SyntaxKind.AnyKeyword);
     }
 
-    function createAddPropertyDeclarationAction(context: textChanges.TextChangesContext, classDeclarationSourceFile: SourceFile, classDeclaration: ClassLikeDeclaration, makeStatic: boolean, tokenName: string, typeNode: TypeNode): CodeFixAction {
+    function createAddPropertyDeclarationAction(context: CodeFixContext, classDeclarationSourceFile: SourceFile, classDeclaration: ClassLikeDeclaration, makeStatic: boolean, tokenName: string, typeNode: TypeNode): CodeFixAction {
         const description = formatStringFromArgs(getLocaleSpecificMessage(makeStatic ? Diagnostics.Declare_static_property_0 : Diagnostics.Declare_property_0), [tokenName]);
         const changes = textChanges.ChangeTracker.with(context, t => addPropertyDeclaration(t, classDeclarationSourceFile, classDeclaration, tokenName, typeNode, makeStatic));
         return { description, changes, fixId };
@@ -159,7 +159,7 @@ namespace ts.codefix {
         changeTracker.insertNodeAtClassStart(classDeclarationSourceFile, classDeclaration, property);
     }
 
-    function createAddIndexSignatureAction(context: textChanges.TextChangesContext, classDeclarationSourceFile: SourceFile, classDeclaration: ClassLikeDeclaration, tokenName: string, typeNode: TypeNode): CodeFixAction {
+    function createAddIndexSignatureAction(context: CodeFixContext, classDeclarationSourceFile: SourceFile, classDeclaration: ClassLikeDeclaration, tokenName: string, typeNode: TypeNode): CodeFixAction {
         // Index signatures cannot have the static modifier.
         const stringTypeNode = createKeywordTypeNode(SyntaxKind.StringKeyword);
         const indexingParameter = createParameter(
@@ -181,7 +181,7 @@ namespace ts.codefix {
         return { description: formatStringFromArgs(getLocaleSpecificMessage(Diagnostics.Add_index_signature_for_property_0), [tokenName]), changes, fixId: undefined };
     }
 
-    function getActionForMethodDeclaration(context: textChanges.TextChangesContext, classDeclarationSourceFile: SourceFile, classDeclaration: ClassLikeDeclaration, token: Identifier, callExpression: CallExpression, makeStatic: boolean, inJs: boolean): CodeFixAction | undefined {
+    function getActionForMethodDeclaration(context: CodeFixContext, classDeclarationSourceFile: SourceFile, classDeclaration: ClassLikeDeclaration, token: Identifier, callExpression: CallExpression, makeStatic: boolean, inJs: boolean): CodeFixAction | undefined {
         const description = formatStringFromArgs(getLocaleSpecificMessage(makeStatic ? Diagnostics.Declare_static_method_0 : Diagnostics.Declare_method_0), [token.text]);
         const changes = textChanges.ChangeTracker.with(context, t => addMethodDeclaration(t, classDeclarationSourceFile, classDeclaration, token, callExpression, makeStatic, inJs));
         return { description, changes, fixId };

src/services/codefixes/importFixes.ts

@@ -29,12 +29,8 @@ namespace ts.codefix {
         symbolName: string;
     }
 
-    interface SymbolAndTokenContext extends SymbolContext {
+    interface ImportCodeFixContext extends SymbolContext {
         symbolToken: Identifier | undefined;
-    }
-
-    interface ImportCodeFixContext extends SymbolAndTokenContext {
-        host: LanguageServiceHost;
         program: Program;
         checker: TypeChecker;
         compilerOptions: CompilerOptions;
@@ -173,7 +169,6 @@ namespace ts.codefix {
         const symbolToken = cast(getTokenAtPosition(context.sourceFile, context.span.start, /*includeJsDocComment*/ false), isIdentifier);
         return {
             host: context.host,
-            newLineCharacter: context.newLineCharacter,
             formatContext: context.formatContext,
             sourceFile: context.sourceFile,
             program,
@@ -472,7 +467,7 @@ namespace ts.codefix {
         addJsExtension: boolean,
     ): string | undefined {
         const roots = getEffectiveTypeRoots(options, host);
-        return roots && firstDefined(roots, unNormalizedTypeRoot => {
+        return firstDefined(roots, unNormalizedTypeRoot => {
             const typeRoot = toPath(unNormalizedTypeRoot, /*basePath*/ undefined, getCanonicalFileName);
             if (startsWith(moduleFileName, typeRoot)) {
                 return removeExtensionAndIndexPostFix(moduleFileName.substring(typeRoot.length + 1), options, addJsExtension);

src/services/completions.ts

@@ -627,7 +627,6 @@ namespace ts.Completions {
             host,
             program,
             checker,
-            newLineCharacter: host.getNewLine(),
             compilerOptions,
             sourceFile,
             formatContext,

src/services/findAllReferences.ts

@@ -44,7 +44,7 @@ namespace ts.FindAllReferences {
     export function findReferencedSymbols(program: Program, cancellationToken: CancellationToken, sourceFiles: ReadonlyArray<SourceFile>, sourceFile: SourceFile, position: number): ReferencedSymbol[] | undefined {
         const referencedSymbols = findAllReferencedSymbols(program, cancellationToken, sourceFiles, sourceFile, position);
         const checker = program.getTypeChecker();
-        return !referencedSymbols || !referencedSymbols.length ? undefined : mapDefined(referencedSymbols, ({ definition, references }) =>
+        return !referencedSymbols || !referencedSymbols.length ? undefined : mapDefined<SymbolAndEntries, ReferencedSymbol>(referencedSymbols, ({ definition, references }) =>
             // Only include referenced symbols that have a valid definition.
             definition && { definition: definitionToReferencedSymbolDefinitionInfo(definition, checker), references: references.map(toReferenceEntry) });
     }

src/services/formatting/formatting.ts

@@ -14,10 +14,14 @@ namespace ts.formatting {
         kind: SyntaxKind;
     }
 
+    export interface TextRangeWithTriviaKind extends TextRange {
+        kind: TriviaKind;
+    }
+
     export interface TokenInfo {
-        leadingTrivia: TextRangeWithKind[];
+        leadingTrivia: TextRangeWithTriviaKind[];
         token: TextRangeWithKind;
-        trailingTrivia: TextRangeWithKind[];
+        trailingTrivia: TextRangeWithTriviaKind[];
     }
 
     const enum Constants {
@@ -66,11 +70,6 @@ namespace ts.formatting {
         recomputeIndentation(lineAddedByFormatting: boolean): void;
     }
 
-    interface Indentation {
-        indentation: number;
-        delta: number;
-    }
-
     export function formatOnEnter(position: number, sourceFile: SourceFile, formatContext: FormatContext): TextChange[] {
         const line = sourceFile.getLineAndCharacterOfPosition(position).line;
         if (line === 0) {
@@ -469,39 +468,35 @@ namespace ts.formatting {
             inheritedIndentation: number,
             parent: Node,
             parentDynamicIndentation: DynamicIndentation,
-            effectiveParentStartLine: number): Indentation {
-
-            let indentation = inheritedIndentation;
-            let delta = SmartIndenter.shouldIndentChildNode(node) ? options.indentSize : 0;
+            effectiveParentStartLine: number
+        ): { indentation: number, delta: number } {
+            const delta = SmartIndenter.shouldIndentChildNode(node) ? options.indentSize : 0;
 
             if (effectiveParentStartLine === startLine) {
                 // if node is located on the same line with the parent
                 // - inherit indentation from the parent
                 // - push children if either parent of node itself has non-zero delta
-                indentation = startLine === lastIndentedLine
-                    ? indentationOnLastIndentedLine
-                    : parentDynamicIndentation.getIndentation();
-                delta = Math.min(options.indentSize, parentDynamicIndentation.getDelta(node) + delta);
+                return {
+                    indentation: startLine === lastIndentedLine ? indentationOnLastIndentedLine : parentDynamicIndentation.getIndentation(),
+                    delta: Math.min(options.indentSize, parentDynamicIndentation.getDelta(node) + delta)
+                };
             }
-            else if (indentation === Constants.Unknown) {
+            else if (inheritedIndentation === Constants.Unknown) {
                 if (node.kind === SyntaxKind.OpenParenToken && startLine === lastIndentedLine) {
                     // the is used for chaining methods formatting
                     // - we need to get the indentation on last line and the delta of parent
-                    indentation = indentationOnLastIndentedLine;
-                    delta = parentDynamicIndentation.getDelta(node);
+                    return { indentation: indentationOnLastIndentedLine, delta: parentDynamicIndentation.getDelta(node) };
                 }
                 else if (SmartIndenter.childStartsOnTheSameLineWithElseInIfStatement(parent, node, startLine, sourceFile)) {
-                    indentation = parentDynamicIndentation.getIndentation();
+                    return { indentation: parentDynamicIndentation.getIndentation(), delta };
                 }
                 else {
-                    indentation = parentDynamicIndentation.getIndentation() + parentDynamicIndentation.getDelta(node);
+                    return { indentation: parentDynamicIndentation.getIndentation() + parentDynamicIndentation.getDelta(node), delta };
                 }
             }
-
-            return {
-                indentation,
-                delta
-            };
+            else {
+                return { indentation: inheritedIndentation, delta };
+            }
         }
 
         function getFirstNonDecoratorTokenOfNode(node: Node) {

src/services/formatting/formattingScanner.ts

@@ -31,8 +31,8 @@ namespace ts.formatting {
         scanner.setTextPos(startPos);
 
         let wasNewLine = true;
-        let leadingTrivia: TextRangeWithKind[] | undefined;
-        let trailingTrivia: TextRangeWithKind[] | undefined;
+        let leadingTrivia: TextRangeWithTriviaKind[] | undefined;
+        let trailingTrivia: TextRangeWithTriviaKind[] | undefined;
 
         let savedPos: number;
         let lastScanAction: ScanAction | undefined;
@@ -77,7 +77,7 @@ namespace ts.formatting {
 
                 // consume leading trivia
                 scanner.scan();
-                const item = {
+                const item: TextRangeWithTriviaKind = {
                     pos,
                     end: scanner.getStartPos(),
                     kind: t
@@ -188,7 +188,7 @@ namespace ts.formatting {
                 if (!isTrivia(currentToken)) {
                     break;
                 }
-                const trivia = {
+                const trivia: TextRangeWithTriviaKind = {
                     pos: scanner.getStartPos(),
                     end: scanner.getTextPos(),
                     kind: currentToken

src/services/goToDefinition.ts

@@ -127,30 +127,16 @@ namespace ts.GoToDefinition {
         }
 
         const symbol = typeChecker.getSymbolAtLocation(node);
-        if (!symbol) {
-            return undefined;
-        }
-
-        const type = typeChecker.getTypeOfSymbolAtLocation(symbol, node);
+        const type = symbol && typeChecker.getTypeOfSymbolAtLocation(symbol, node);
         if (!type) {
             return undefined;
         }
 
         if (type.flags & TypeFlags.Union && !(type.flags & TypeFlags.Enum)) {
-            const result: DefinitionInfo[] = [];
-            forEach((<UnionType>type).types, t => {
-                if (t.symbol) {
-                    addRange(/*to*/ result, /*from*/ getDefinitionFromSymbol(typeChecker, t.symbol, node));
-                }
-            });
-            return result;
+            return flatMap((<UnionType>type).types, t => t.symbol && getDefinitionFromSymbol(typeChecker, t.symbol, node));
         }
 
-        if (!type.symbol) {
-            return undefined;
-        }
-
-        return getDefinitionFromSymbol(typeChecker, type.symbol, node);
+        return type.symbol && getDefinitionFromSymbol(typeChecker, type.symbol, node);
     }
 
     export function getDefinitionAndBoundSpan(program: Program, sourceFile: SourceFile, position: number): DefinitionInfoAndBoundSpan {
@@ -199,66 +185,32 @@ namespace ts.GoToDefinition {
     }
 
     function getDefinitionFromSymbol(typeChecker: TypeChecker, symbol: Symbol, node: Node): DefinitionInfo[] {
-        const result: DefinitionInfo[] = [];
-        const declarations = symbol.getDeclarations();
         const { symbolName, symbolKind, containerName } = getSymbolInfo(typeChecker, symbol, node);
+        return getConstructSignatureDefinition() || getCallSignatureDefinition() || map(symbol.declarations, declaration => createDefinitionInfo(declaration, symbolKind, symbolName, containerName));
 
-        if (!tryAddConstructSignature(symbol, node, symbolKind, symbolName, containerName, result) &&
-            !tryAddCallSignature(symbol, node, symbolKind, symbolName, containerName, result)) {
-            // Just add all the declarations.
-            forEach(declarations, declaration => {
-                result.push(createDefinitionInfo(declaration, symbolKind, symbolName, containerName));
-            });
-        }
-
-        return result;
-
-        function tryAddConstructSignature(symbol: Symbol, location: Node, symbolKind: ScriptElementKind, symbolName: string, containerName: string, result: DefinitionInfo[]) {
+        function getConstructSignatureDefinition(): DefinitionInfo[] | undefined {
             // Applicable only if we are in a new expression, or we are on a constructor declaration
             // and in either case the symbol has a construct signature definition, i.e. class
-            if (isNewExpressionTarget(location) || location.kind === SyntaxKind.ConstructorKeyword) {
-                if (symbol.flags & SymbolFlags.Class) {
-                    // Find the first class-like declaration and try to get the construct signature.
-                    for (const declaration of symbol.getDeclarations()) {
-                        if (isClassLike(declaration)) {
-                            return tryAddSignature(
-                                declaration.members, /*selectConstructors*/ true, symbolKind, symbolName, containerName, result);
-                        }
-                    }
-
-                    Debug.fail("Expected declaration to have at least one class-like declaration");
-                }
+            if (isNewExpressionTarget(node) || node.kind === SyntaxKind.ConstructorKeyword && symbol.flags & SymbolFlags.Class) {
+                const cls = find(symbol.declarations, isClassLike) || Debug.fail("Expected declaration to have at least one class-like declaration");
+                return getSignatureDefinition(cls.members, /*selectConstructors*/ true);
             }
-            return false;
         }
 
-        function tryAddCallSignature(symbol: Symbol, location: Node, symbolKind: ScriptElementKind, symbolName: string, containerName: string, result: DefinitionInfo[]) {
-            if (isCallExpressionTarget(location) || isNewExpressionTarget(location) || isNameOfFunctionDeclaration(location)) {
-                return tryAddSignature(symbol.declarations, /*selectConstructors*/ false, symbolKind, symbolName, containerName, result);
-            }
-            return false;
+        function getCallSignatureDefinition(): DefinitionInfo[] | undefined {
+            return isCallExpressionTarget(node) || isNewExpressionTarget(node) || isNameOfFunctionDeclaration(node)
+                ? getSignatureDefinition(symbol.declarations, /*selectConstructors*/ false)
+                : undefined;
         }
 
-        function tryAddSignature(signatureDeclarations: ReadonlyArray<Declaration> | undefined, selectConstructors: boolean, symbolKind: ScriptElementKind, symbolName: string, containerName: string, result: DefinitionInfo[]) {
+        function getSignatureDefinition(signatureDeclarations: ReadonlyArray<Declaration> | undefined, selectConstructors: boolean): DefinitionInfo[] | undefined {
             if (!signatureDeclarations) {
-                return false;
+                return undefined;
             }
-
-            const declarations: Declaration[] = [];
-            let definition: Declaration | undefined;
-
-            for (const d of signatureDeclarations) {
-                if (selectConstructors ? d.kind === SyntaxKind.Constructor : isSignatureDeclaration(d)) {
-                    declarations.push(d);
-                    if ((<FunctionLikeDeclaration>d).body) definition = d;
-                }
-            }
-
-            if (declarations.length) {
-                result.push(createDefinitionInfo(definition || lastOrUndefined(declarations), symbolKind, symbolName, containerName));
-                return true;
-            }
-            return false;
+            const declarations = signatureDeclarations.filter(selectConstructors ? isConstructorDeclaration : isSignatureDeclaration);
+            return declarations.length
+                ? [createDefinitionInfo(find(declarations, d => !!(<FunctionLikeDeclaration>d).body) || last(declarations), symbolKind, symbolName, containerName)]
+                : undefined;
         }
     }
 

src/services/refactorProvider.ts

@@ -1,12 +1,6 @@
 /* @internal */
 namespace ts {
     export interface Refactor {
-        /** An unique code associated with each refactor */
-        name: string;
-
-        /** Description of the refactor to display in the UI of the editor */
-        description: string;
-
         /** Compute the associated code actions */
         getEditsForAction(context: RefactorContext, actionName: string): RefactorEditInfo | undefined;
 
@@ -19,7 +13,6 @@ namespace ts {
         startPosition: number;
         endPosition?: number;
         program: Program;
-        host: LanguageServiceHost;
         cancellationToken?: CancellationToken;
     }
 
@@ -28,8 +21,9 @@ namespace ts {
         // e.g.  nonSuggestableRefactors[refactorCode] -> the refactor you want
         const refactors: Map<Refactor> = createMap<Refactor>();
 
-        export function registerRefactor(refactor: Refactor) {
-            refactors.set(refactor.name, refactor);
+        /** @param name An unique code associated with each refactor. Does not have to be human-readable. */
+        export function registerRefactor(name: string, refactor: Refactor) {
+            refactors.set(name, refactor);
         }
 
         export function getApplicableRefactors(context: RefactorContext): ApplicableRefactorInfo[] {

src/services/refactors/annotateWithTypeFromJSDoc.ts

@@ -1,13 +1,10 @@
 /* @internal */
 namespace ts.refactor.annotateWithTypeFromJSDoc {
+    const refactorName = "Annotate with type from JSDoc";
     const actionName = "annotate";
+    const description = Diagnostics.Annotate_with_type_from_JSDoc.message;
+    registerRefactor(refactorName, { getEditsForAction, getAvailableActions });
 
-    const annotateTypeFromJSDoc: Refactor = {
-        name: "Annotate with type from JSDoc",
-        description: Diagnostics.Annotate_with_type_from_JSDoc.message,
-        getEditsForAction,
-        getAvailableActions
-    };
     type DeclarationWithType =
         | FunctionLikeDeclaration
         | VariableDeclaration
@@ -15,8 +12,6 @@ namespace ts.refactor.annotateWithTypeFromJSDoc {
         | PropertySignature
         | PropertyDeclaration;
 
-    registerRefactor(annotateTypeFromJSDoc);
-
     function getAvailableActions(context: RefactorContext): ApplicableRefactorInfo[] | undefined {
         if (isInJavaScriptFile(context.file)) {
             return undefined;
@@ -25,11 +20,11 @@ namespace ts.refactor.annotateWithTypeFromJSDoc {
         const node = getTokenAtPosition(context.file, context.startPosition, /*includeJsDocComment*/ false);
         if (hasUsableJSDoc(findAncestor(node, isDeclarationWithType))) {
             return [{
-                name: annotateTypeFromJSDoc.name,
-                description: annotateTypeFromJSDoc.description,
+                name: refactorName,
+                description,
                 actions: [
                     {
-                        description: annotateTypeFromJSDoc.description,
+                        description,
                         name: actionName
                     }
                 ]

src/services/refactors/convertFunctionToEs6Class.ts

@@ -1,16 +1,10 @@
 /* @internal */
 
 namespace ts.refactor.convertFunctionToES6Class {
+    const refactorName = "Convert to ES2015 class";
     const actionName = "convert";
-
-    const convertFunctionToES6Class: Refactor = {
-        name: "Convert to ES2015 class",
-        description: Diagnostics.Convert_function_to_an_ES2015_class.message,
-        getEditsForAction,
-        getAvailableActions
-    };
-
-    registerRefactor(convertFunctionToES6Class);
+    const description = Diagnostics.Convert_function_to_an_ES2015_class.message;
+    registerRefactor(refactorName, { getEditsForAction, getAvailableActions });
 
     function getAvailableActions(context: RefactorContext): ApplicableRefactorInfo[] | undefined {
         if (!isInJavaScriptFile(context.file)) {
@@ -29,11 +23,11 @@ namespace ts.refactor.convertFunctionToES6Class {
         if ((symbol.flags & SymbolFlags.Function) && symbol.members && (symbol.members.size > 0)) {
             return [
                 {
-                    name: convertFunctionToES6Class.name,
-                    description: convertFunctionToES6Class.description,
+                    name: refactorName,
+                    description,
                     actions: [
                         {
-                            description: convertFunctionToES6Class.description,
+                            description,
                             name: actionName
                         }
                     ]

src/services/refactors/convertToEs6Module.ts

@@ -1,15 +1,8 @@
 /* @internal */
 namespace ts.refactor {
     const actionName = "Convert to ES6 module";
-
-    const convertToEs6Module: Refactor = {
-        name: actionName,
-        description: getLocaleSpecificMessage(Diagnostics.Convert_to_ES6_module),
-        getEditsForAction,
-        getAvailableActions,
-    };
-
-    registerRefactor(convertToEs6Module);
+    const description = getLocaleSpecificMessage(Diagnostics.Convert_to_ES6_module);
+    registerRefactor(actionName, { getEditsForAction, getAvailableActions });
 
     function getAvailableActions(context: RefactorContext): ApplicableRefactorInfo[] | undefined {
         const { file, startPosition } = context;
@@ -20,11 +13,11 @@ namespace ts.refactor {
         const node = getTokenAtPosition(file, startPosition, /*includeJsDocComment*/ false);
         return !isAtTriggerLocation(file, node) ? undefined : [
             {
-                name: convertToEs6Module.name,
-                description: convertToEs6Module.description,
+                name: actionName,
+                description,
                 actions: [
                     {
-                        description: convertToEs6Module.description,
+                        description,
                         name: actionName,
                     },
                 ],

src/services/refactors/extractSymbol.ts

@@ -3,14 +3,8 @@
 
 /* @internal */
 namespace ts.refactor.extractSymbol {
-    const extractSymbol: Refactor = {
-        name: "Extract Symbol",
-        description: getLocaleSpecificMessage(Diagnostics.Extract_symbol),
-        getAvailableActions,
-        getEditsForAction,
-    };
-
-    registerRefactor(extractSymbol);
+    const refactorName = "Extract Symbol";
+    registerRefactor(refactorName, { getAvailableActions, getEditsForAction });
 
     /**
      * Compute the associated code actions
@@ -77,7 +71,7 @@ namespace ts.refactor.extractSymbol {
 
         if (functionActions.length) {
             infos.push({
-                name: extractSymbol.name,
+                name: refactorName,
                 description: getLocaleSpecificMessage(Diagnostics.Extract_function),
                 actions: functionActions
             });
@@ -85,7 +79,7 @@ namespace ts.refactor.extractSymbol {
 
         if (constantActions.length) {
             infos.push({
-                name: extractSymbol.name,
+                name: refactorName,
                 description: getLocaleSpecificMessage(Diagnostics.Extract_constant),
                 actions: constantActions
             });

src/services/refactors/installTypesForPackage.ts

@@ -1,15 +1,9 @@
 /* @internal */
 namespace ts.refactor.installTypesForPackage {
+    const refactorName = "Install missing types package";
     const actionName = "install";
-
-    const installTypesForPackage: Refactor = {
-        name: "Install missing types package",
-        description: "Install missing types package",
-        getEditsForAction,
-        getAvailableActions,
-    };
-
-    registerRefactor(installTypesForPackage);
+    const description = "Install missing types package";
+    registerRefactor(refactorName, { getEditsForAction, getAvailableActions });
 
     function getAvailableActions(context: RefactorContext): ApplicableRefactorInfo[] | undefined {
         if (getStrictOptionValue(context.program.getCompilerOptions(), "noImplicitAny")) {
@@ -20,8 +14,8 @@ namespace ts.refactor.installTypesForPackage {
         const action = getAction(context);
         return action && [
             {
-                name: installTypesForPackage.name,
-                description: installTypesForPackage.description,
+                name: refactorName,
+                description,
                 actions: [
                     {
                         description: action.description,

src/services/refactors/useDefaultImport.ts

@@ -1,15 +1,8 @@
 /* @internal */
 namespace ts.refactor.installTypesForPackage {
     const actionName = "Convert to default import";
-
-    const useDefaultImport: Refactor = {
-        name: actionName,
-        description: getLocaleSpecificMessage(Diagnostics.Convert_to_default_import),
-        getEditsForAction,
-        getAvailableActions,
-    };
-
-    registerRefactor(useDefaultImport);
+    const description = getLocaleSpecificMessage(Diagnostics.Convert_to_default_import);
+    registerRefactor(actionName, { getEditsForAction, getAvailableActions });
 
     function getAvailableActions(context: RefactorContext): ApplicableRefactorInfo[] | undefined {
         const { file, startPosition, program } = context;
@@ -31,11 +24,11 @@ namespace ts.refactor.installTypesForPackage {
 
         return [
             {
-                name: useDefaultImport.name,
-                description: useDefaultImport.description,
+                name: actionName,
+                description,
                 actions: [
                     {
-                        description: useDefaultImport.description,
+                        description,
                         name: actionName,
                     },
                 ],

src/services/services.ts

@@ -1887,12 +1887,11 @@ namespace ts {
             synchronizeHostData();
             const sourceFile = getValidSourceFile(fileName);
             const span = createTextSpanFromBounds(start, end);
-            const newLineCharacter = getNewLineOrDefaultFromHost(host);
             const formatContext = formatting.getFormatContext(formatOptions);
 
             return flatMap(deduplicate(errorCodes, equateValues, compareValues), errorCode => {
                 cancellationToken.throwIfCancellationRequested();
-                return codefix.getFixes({ errorCode, sourceFile, span, program, newLineCharacter, host, cancellationToken, formatContext });
+                return codefix.getFixes({ errorCode, sourceFile, span, program, host, cancellationToken, formatContext });
             });
         }
 
@@ -1900,10 +1899,9 @@ namespace ts {
             synchronizeHostData();
             Debug.assert(scope.type === "file");
             const sourceFile = getValidSourceFile(scope.fileName);
-            const newLineCharacter = getNewLineOrDefaultFromHost(host);
             const formatContext = formatting.getFormatContext(formatOptions);
 
-            return codefix.getAllFixes({ fixId, sourceFile, program, newLineCharacter, host, cancellationToken, formatContext });
+            return codefix.getAllFixes({ fixId, sourceFile, program, host, cancellationToken, formatContext });
         }
 
         function applyCodeActionCommand(action: CodeActionCommand): Promise<ApplyCodeActionCommandResult>;
@@ -2134,7 +2132,6 @@ namespace ts {
                 startPosition,
                 endPosition,
                 program: getProgram(),
-                newLineCharacter: formatOptions ? formatOptions.newLineCharacter : host.getNewLine(),
                 host,
                 formatContext: formatting.getFormatContext(formatOptions),
                 cancellationToken,

src/services/textChanges.ts

@@ -187,7 +187,7 @@ namespace ts.textChanges {
     }
 
     export interface TextChangesContext {
-        newLineCharacter: string;
+        host: LanguageServiceHost;
         formatContext: ts.formatting.FormatContext;
     }
 
@@ -199,7 +199,7 @@ namespace ts.textChanges {
         private readonly nodesInsertedAtClassStarts = createMap<{ sourceFile: SourceFile, cls: ClassLikeDeclaration, members: ClassElement[] }>();
 
         public static fromContext(context: TextChangesContext): ChangeTracker {
-            return new ChangeTracker(context.newLineCharacter === "\n" ? NewLineKind.LineFeed : NewLineKind.CarriageReturnLineFeed, context.formatContext);
+            return new ChangeTracker(getNewLineOrDefaultFromHost(context.host, context.formatContext.options) === "\n" ? NewLineKind.LineFeed : NewLineKind.CarriageReturnLineFeed, context.formatContext);
         }
 
         public static with(context: TextChangesContext, cb: (tracker: ChangeTracker) => void): FileTextChanges[] {

src/services/utilities.ts

@@ -1259,8 +1259,10 @@ namespace ts {
     /**
      * The default is CRLF.
      */
-    export function getNewLineOrDefaultFromHost(host: LanguageServiceHost | LanguageServiceShimHost) {
-        return host.getNewLine ? host.getNewLine() : carriageReturnLineFeed;
+    export function getNewLineOrDefaultFromHost(host: LanguageServiceHost | LanguageServiceShimHost, formatSettings?: FormatCodeSettings) {
+        return (formatSettings && formatSettings.newLineCharacter) ||
+            (host.getNewLine && host.getNewLine()) ||
+            carriageReturnLineFeed;
     }
 
     export function lineBreakPart() {

tests/baselines/reference/api/tsserverlibrary.d.ts

@@ -7243,7 +7243,7 @@ declare namespace ts.server {
         private getCombinedCodeFix({scope, fixId}, simplifiedResult);
         private applyCodeActionCommand(args);
         private getStartAndEndPosition(args, scriptInfo);
-        private mapCodeAction(project, {description, changes: unmappedChanges, commands});
+        private mapCodeAction(project, {description, changes: unmappedChanges, commands, fixId});
         private mapTextChangesToCodeEdits(project, textChanges);
         private mapTextChangesToCodeEditsUsingScriptinfo(textChanges, scriptInfo);
         private convertTextChangeToCodeEdit(change, scriptInfo);

tests/baselines/reference/inferObjectTypeFromStringLiteralToKeyof.js

@@ -1,8 +1,11 @@
 //// [inferObjectTypeFromStringLiteralToKeyof.ts]
-declare function inference<T>(target: T, name: keyof T): void;
+declare function inference1<T>(name: keyof T): T;
+declare function inference2<T>(target: T, name: keyof T): T;
 declare var two: "a" | "d";
-inference({ a: 1, b: 2, c: 3, d(n) { return n } }, two);
+const x = inference1(two);
+const y = inference2({ a: 1, b: 2, c: 3, d(n) { return n } }, two);
 
 
 //// [inferObjectTypeFromStringLiteralToKeyof.js]
-inference({ a: 1, b: 2, c: 3, d: function (n) { return n; } }, two);
+var x = inference1(two);
+var y = inference2({ a: 1, b: 2, c: 3, d: function (n) { return n; } }, two);

tests/baselines/reference/inferObjectTypeFromStringLiteralToKeyof.symbols

@@ -1,22 +1,36 @@
 === tests/cases/compiler/inferObjectTypeFromStringLiteralToKeyof.ts ===
-declare function inference<T>(target: T, name: keyof T): void;
->inference : Symbol(inference, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 0, 0))
->T : Symbol(T, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 0, 27))
->target : Symbol(target, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 0, 30))
->T : Symbol(T, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 0, 27))
->name : Symbol(name, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 0, 40))
->T : Symbol(T, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 0, 27))
+declare function inference1<T>(name: keyof T): T;
+>inference1 : Symbol(inference1, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 0, 0))
+>T : Symbol(T, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 0, 28))
+>name : Symbol(name, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 0, 31))
+>T : Symbol(T, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 0, 28))
+>T : Symbol(T, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 0, 28))
+
+declare function inference2<T>(target: T, name: keyof T): T;
+>inference2 : Symbol(inference2, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 0, 49))
+>T : Symbol(T, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 1, 28))
+>target : Symbol(target, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 1, 31))
+>T : Symbol(T, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 1, 28))
+>name : Symbol(name, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 1, 41))
+>T : Symbol(T, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 1, 28))
+>T : Symbol(T, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 1, 28))
 
 declare var two: "a" | "d";
->two : Symbol(two, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 1, 11))
+>two : Symbol(two, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 2, 11))
 
-inference({ a: 1, b: 2, c: 3, d(n) { return n } }, two);
->inference : Symbol(inference, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 0, 0))
->a : Symbol(a, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 2, 11))
->b : Symbol(b, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 2, 17))
->c : Symbol(c, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 2, 23))
->d : Symbol(d, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 2, 29))
->n : Symbol(n, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 2, 32))
->n : Symbol(n, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 2, 32))
->two : Symbol(two, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 1, 11))
+const x = inference1(two);
+>x : Symbol(x, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 3, 5))
+>inference1 : Symbol(inference1, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 0, 0))
+>two : Symbol(two, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 2, 11))
+
+const y = inference2({ a: 1, b: 2, c: 3, d(n) { return n } }, two);
+>y : Symbol(y, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 4, 5))
+>inference2 : Symbol(inference2, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 0, 49))
+>a : Symbol(a, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 4, 22))
+>b : Symbol(b, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 4, 28))
+>c : Symbol(c, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 4, 34))
+>d : Symbol(d, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 4, 40))
+>n : Symbol(n, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 4, 43))
+>n : Symbol(n, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 4, 43))
+>two : Symbol(two, Decl(inferObjectTypeFromStringLiteralToKeyof.ts, 2, 11))
 

tests/baselines/reference/inferObjectTypeFromStringLiteralToKeyof.types

@@ -1,18 +1,33 @@
 === tests/cases/compiler/inferObjectTypeFromStringLiteralToKeyof.ts ===
-declare function inference<T>(target: T, name: keyof T): void;
->inference : <T>(target: T, name: keyof T) => void
+declare function inference1<T>(name: keyof T): T;
+>inference1 : <T>(name: keyof T) => T
+>T : T
+>name : keyof T
+>T : T
+>T : T
+
+declare function inference2<T>(target: T, name: keyof T): T;
+>inference2 : <T>(target: T, name: keyof T) => T
 >T : T
 >target : T
 >T : T
 >name : keyof T
 >T : T
+>T : T
 
 declare var two: "a" | "d";
 >two : "a" | "d"
 
-inference({ a: 1, b: 2, c: 3, d(n) { return n } }, two);
->inference({ a: 1, b: 2, c: 3, d(n) { return n } }, two) : void
->inference : <T>(target: T, name: keyof T) => void
+const x = inference1(two);
+>x : { a: any; d: any; }
+>inference1(two) : { a: any; d: any; }
+>inference1 : <T>(name: keyof T) => T
+>two : "a" | "d"
+
+const y = inference2({ a: 1, b: 2, c: 3, d(n) { return n } }, two);
+>y : { a: number; b: number; c: number; d(n: any): any; }
+>inference2({ a: 1, b: 2, c: 3, d(n) { return n } }, two) : { a: number; b: number; c: number; d(n: any): any; }
+>inference2 : <T>(target: T, name: keyof T) => T
 >{ a: 1, b: 2, c: 3, d(n) { return n } } : { a: number; b: number; c: number; d(n: any): any; }
 >a : number
 >1 : 1

tests/baselines/reference/keyofAndIndexedAccess.js

@@ -552,6 +552,19 @@ class AnotherSampleClass<T> extends SampleClass<T & Foo> {
     }
 }
 new AnotherSampleClass({});
+
+// Positive repro from #17166
+function f3<T, K extends keyof T>(t: T, k: K, tk: T[K]): void {
+    for (let key in t) {
+        key = k // ok, K ==> keyof T
+        t[key] = tk; // ok, T[K] ==> T[keyof T]
+    }
+}
+
+// # 21185
+type Predicates<TaggedRecord> = {
+  [T in keyof TaggedRecord]: (variant: TaggedRecord[keyof TaggedRecord]) => variant is TaggedRecord[T]
+}
 
 
 //// [keyofAndIndexedAccess.js]
@@ -928,6 +941,13 @@ var AnotherSampleClass = /** @class */ (function (_super) {
     return AnotherSampleClass;
 }(SampleClass));
 new AnotherSampleClass({});
+// Positive repro from #17166
+function f3(t, k, tk) {
+    for (var key in t) {
+        key = k; // ok, K ==> keyof T
+        t[key] = tk; // ok, T[K] ==> T[keyof T]
+    }
+}
 
 
 //// [keyofAndIndexedAccess.d.ts]
@@ -1188,3 +1208,7 @@ declare class AnotherSampleClass<T> extends SampleClass<T & Foo> {
     constructor(props: T);
     brokenMethod(): void;
 }
+declare function f3<T, K extends keyof T>(t: T, k: K, tk: T[K]): void;
+declare type Predicates<TaggedRecord> = {
+    [T in keyof TaggedRecord]: (variant: TaggedRecord[keyof TaggedRecord]) => variant is TaggedRecord[T];
+};

tests/baselines/reference/keyofAndIndexedAccess.symbols

@@ -1962,3 +1962,48 @@ class AnotherSampleClass<T> extends SampleClass<T & Foo> {
 new AnotherSampleClass({});
 >AnotherSampleClass : Symbol(AnotherSampleClass, Decl(keyofAndIndexedAccess.ts, 540, 54))
 
+// Positive repro from #17166
+function f3<T, K extends keyof T>(t: T, k: K, tk: T[K]): void {
+>f3 : Symbol(f3, Decl(keyofAndIndexedAccess.ts, 552, 27))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 555, 12))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 555, 14))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 555, 12))
+>t : Symbol(t, Decl(keyofAndIndexedAccess.ts, 555, 34))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 555, 12))
+>k : Symbol(k, Decl(keyofAndIndexedAccess.ts, 555, 39))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 555, 14))
+>tk : Symbol(tk, Decl(keyofAndIndexedAccess.ts, 555, 45))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 555, 12))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 555, 14))
+
+    for (let key in t) {
+>key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 556, 12))
+>t : Symbol(t, Decl(keyofAndIndexedAccess.ts, 555, 34))
+
+        key = k // ok, K ==> keyof T
+>key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 556, 12))
+>k : Symbol(k, Decl(keyofAndIndexedAccess.ts, 555, 39))
+
+        t[key] = tk; // ok, T[K] ==> T[keyof T]
+>t : Symbol(t, Decl(keyofAndIndexedAccess.ts, 555, 34))
+>key : Symbol(key, Decl(keyofAndIndexedAccess.ts, 556, 12))
+>tk : Symbol(tk, Decl(keyofAndIndexedAccess.ts, 555, 45))
+    }
+}
+
+// # 21185
+type Predicates<TaggedRecord> = {
+>Predicates : Symbol(Predicates, Decl(keyofAndIndexedAccess.ts, 560, 1))
+>TaggedRecord : Symbol(TaggedRecord, Decl(keyofAndIndexedAccess.ts, 563, 16))
+
+  [T in keyof TaggedRecord]: (variant: TaggedRecord[keyof TaggedRecord]) => variant is TaggedRecord[T]
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 564, 3))
+>TaggedRecord : Symbol(TaggedRecord, Decl(keyofAndIndexedAccess.ts, 563, 16))
+>variant : Symbol(variant, Decl(keyofAndIndexedAccess.ts, 564, 30))
+>TaggedRecord : Symbol(TaggedRecord, Decl(keyofAndIndexedAccess.ts, 563, 16))
+>TaggedRecord : Symbol(TaggedRecord, Decl(keyofAndIndexedAccess.ts, 563, 16))
+>variant : Symbol(variant, Decl(keyofAndIndexedAccess.ts, 564, 30))
+>TaggedRecord : Symbol(TaggedRecord, Decl(keyofAndIndexedAccess.ts, 563, 16))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 564, 3))
+}
+

tests/baselines/reference/keyofAndIndexedAccess.types

@@ -2294,3 +2294,51 @@ new AnotherSampleClass({});
 >AnotherSampleClass : typeof AnotherSampleClass
 >{} : {}
 
+// Positive repro from #17166
+function f3<T, K extends keyof T>(t: T, k: K, tk: T[K]): void {
+>f3 : <T, K extends keyof T>(t: T, k: K, tk: T[K]) => void
+>T : T
+>K : K
+>T : T
+>t : T
+>T : T
+>k : K
+>K : K
+>tk : T[K]
+>T : T
+>K : K
+
+    for (let key in t) {
+>key : keyof T
+>t : T
+
+        key = k // ok, K ==> keyof T
+>key = k : K
+>key : keyof T
+>k : K
+
+        t[key] = tk; // ok, T[K] ==> T[keyof T]
+>t[key] = tk : T[K]
+>t[key] : T[keyof T]
+>t : T
+>key : keyof T
+>tk : T[K]
+    }
+}
+
+// # 21185
+type Predicates<TaggedRecord> = {
+>Predicates : Predicates<TaggedRecord>
+>TaggedRecord : TaggedRecord
+
+  [T in keyof TaggedRecord]: (variant: TaggedRecord[keyof TaggedRecord]) => variant is TaggedRecord[T]
+>T : T
+>TaggedRecord : TaggedRecord
+>variant : TaggedRecord[keyof TaggedRecord]
+>TaggedRecord : TaggedRecord
+>TaggedRecord : TaggedRecord
+>variant : any
+>TaggedRecord : TaggedRecord
+>T : T
+}
+

tests/baselines/reference/keyofAndIndexedAccessErrors.errors.txt

@@ -27,11 +27,21 @@ tests/cases/conformance/types/keyof/keyofAndIndexedAccessErrors.ts(76,5): error
   Type 'T' is not assignable to type 'T & U'.
     Type 'T' is not assignable to type 'U'.
 tests/cases/conformance/types/keyof/keyofAndIndexedAccessErrors.ts(77,5): error TS2322: Type 'keyof (T & U)' is not assignable to type 'keyof (T | U)'.
-tests/cases/conformance/types/keyof/keyofAndIndexedAccessErrors.ts(84,9): error TS2322: Type 'keyof T' is not assignable to type 'K'.
-tests/cases/conformance/types/keyof/keyofAndIndexedAccessErrors.ts(85,9): error TS2322: Type 'T[keyof T]' is not assignable to type 'T[K]'.
+tests/cases/conformance/types/keyof/keyofAndIndexedAccessErrors.ts(86,9): error TS2322: Type 'keyof T' is not assignable to type 'K'.
+tests/cases/conformance/types/keyof/keyofAndIndexedAccessErrors.ts(88,9): error TS2322: Type 'T[keyof T]' is not assignable to type 'T[K]'.
+  Type 'keyof T' is not assignable to type 'K'.
+tests/cases/conformance/types/keyof/keyofAndIndexedAccessErrors.ts(91,5): error TS2322: Type 'T[K]' is not assignable to type 'U[K]'.
+  Type 'T' is not assignable to type 'U'.
+tests/cases/conformance/types/keyof/keyofAndIndexedAccessErrors.ts(94,5): error TS2322: Type 'T[J]' is not assignable to type 'U[J]'.
+  Type 'T' is not assignable to type 'U'.
+tests/cases/conformance/types/keyof/keyofAndIndexedAccessErrors.ts(97,5): error TS2322: Type 'T[K]' is not assignable to type 'T[J]'.
+  Type 'K' is not assignable to type 'J'.
+    Type 'keyof T' is not assignable to type 'J'.
+tests/cases/conformance/types/keyof/keyofAndIndexedAccessErrors.ts(100,5): error TS2322: Type 'T[K]' is not assignable to type 'U[J]'.
+  Type 'T' is not assignable to type 'U'.
 
 
-==== tests/cases/conformance/types/keyof/keyofAndIndexedAccessErrors.ts (27 errors) ====
+==== tests/cases/conformance/types/keyof/keyofAndIndexedAccessErrors.ts (31 errors) ====
     class Shape {
         name: string;
         width: number;
@@ -167,15 +177,42 @@ tests/cases/conformance/types/keyof/keyofAndIndexedAccessErrors.ts(85,9): error
     }
     
     // Repro from #17166
-    function f3<T, K extends keyof T>(obj: T, k: K, value: T[K]): void {
-        for (let key in obj) {
+    function f3<T, K extends keyof T, U extends T, J extends K>(
+        t: T, k: K, tk: T[K], u: U, j: J, uk: U[K], tj: T[J], uj: U[J]): void {
+        for (let key in t) {
+            key = k // ok, K ==> keyof T
             k = key // error, keyof T =/=> K
             ~
 !!! error TS2322: Type 'keyof T' is not assignable to type 'K'.
-            value = obj[key]; // error, T[keyof T] =/=> T[K]
-            ~~~~~
+            t[key] = tk; // ok, T[K] ==> T[keyof T]
+            tk = t[key]; // error, T[keyof T] =/=> T[K]
+            ~~
 !!! error TS2322: Type 'T[keyof T]' is not assignable to type 'T[K]'.
+!!! error TS2322:   Type 'keyof T' is not assignable to type 'K'.
         }
-    }
+        tk = uk;
+        uk = tk; // error
+        ~~
+!!! error TS2322: Type 'T[K]' is not assignable to type 'U[K]'.
+!!! error TS2322:   Type 'T' is not assignable to type 'U'.
     
+        tj = uj;
+        uj = tj; // error
+        ~~
+!!! error TS2322: Type 'T[J]' is not assignable to type 'U[J]'.
+!!! error TS2322:   Type 'T' is not assignable to type 'U'.
+    
+        tk = tj;
+        tj = tk; // error
+        ~~
+!!! error TS2322: Type 'T[K]' is not assignable to type 'T[J]'.
+!!! error TS2322:   Type 'K' is not assignable to type 'J'.
+!!! error TS2322:     Type 'keyof T' is not assignable to type 'J'.
+    
+        tk = uj;
+        uj = tk; // error
+        ~~
+!!! error TS2322: Type 'T[K]' is not assignable to type 'U[J]'.
+!!! error TS2322:   Type 'T' is not assignable to type 'U'.
+    }
     

tests/baselines/reference/keyofAndIndexedAccessErrors.js

@@ -80,13 +80,26 @@ function f20<T, U>(k1: keyof (T | U), k2: keyof (T & U), o1: T | U, o2: T & U) {
 }
 
 // Repro from #17166
-function f3<T, K extends keyof T>(obj: T, k: K, value: T[K]): void {
-    for (let key in obj) {
+function f3<T, K extends keyof T, U extends T, J extends K>(
+    t: T, k: K, tk: T[K], u: U, j: J, uk: U[K], tj: T[J], uj: U[J]): void {
+    for (let key in t) {
+        key = k // ok, K ==> keyof T
         k = key // error, keyof T =/=> K
-        value = obj[key]; // error, T[keyof T] =/=> T[K]
+        t[key] = tk; // ok, T[K] ==> T[keyof T]
+        tk = t[key]; // error, T[keyof T] =/=> T[K]
     }
-}
+    tk = uk;
+    uk = tk; // error
 
+    tj = uj;
+    uj = tj; // error
+
+    tk = tj;
+    tj = tk; // error
+
+    tk = uj;
+    uj = tk; // error
+}
 
 
 //// [keyofAndIndexedAccessErrors.js]
@@ -120,9 +133,19 @@ function f20(k1, k2, o1, o2) {
     k2 = k1;
 }
 // Repro from #17166
-function f3(obj, k, value) {
-    for (var key in obj) {
+function f3(t, k, tk, u, j, uk, tj, uj) {
+    for (var key in t) {
+        key = k; // ok, K ==> keyof T
         k = key; // error, keyof T =/=> K
-        value = obj[key]; // error, T[keyof T] =/=> T[K]
+        t[key] = tk; // ok, T[K] ==> T[keyof T]
+        tk = t[key]; // error, T[keyof T] =/=> T[K]
     }
+    tk = uk;
+    uk = tk; // error
+    tj = uj;
+    uj = tj; // error
+    tk = tj;
+    tj = tk; // error
+    tk = uj;
+    uj = tk; // error
 }

tests/baselines/reference/keyofAndIndexedAccessErrors.symbols

@@ -270,32 +270,90 @@ function f20<T, U>(k1: keyof (T | U), k2: keyof (T & U), o1: T | U, o2: T & U) {
 }
 
 // Repro from #17166
-function f3<T, K extends keyof T>(obj: T, k: K, value: T[K]): void {
+function f3<T, K extends keyof T, U extends T, J extends K>(
 >f3 : Symbol(f3, Decl(keyofAndIndexedAccessErrors.ts, 78, 1))
 >T : Symbol(T, Decl(keyofAndIndexedAccessErrors.ts, 81, 12))
 >K : Symbol(K, Decl(keyofAndIndexedAccessErrors.ts, 81, 14))
 >T : Symbol(T, Decl(keyofAndIndexedAccessErrors.ts, 81, 12))
->obj : Symbol(obj, Decl(keyofAndIndexedAccessErrors.ts, 81, 34))
->T : Symbol(T, Decl(keyofAndIndexedAccessErrors.ts, 81, 12))
->k : Symbol(k, Decl(keyofAndIndexedAccessErrors.ts, 81, 41))
->K : Symbol(K, Decl(keyofAndIndexedAccessErrors.ts, 81, 14))
->value : Symbol(value, Decl(keyofAndIndexedAccessErrors.ts, 81, 47))
+>U : Symbol(U, Decl(keyofAndIndexedAccessErrors.ts, 81, 33))
 >T : Symbol(T, Decl(keyofAndIndexedAccessErrors.ts, 81, 12))
+>J : Symbol(J, Decl(keyofAndIndexedAccessErrors.ts, 81, 46))
 >K : Symbol(K, Decl(keyofAndIndexedAccessErrors.ts, 81, 14))
 
-    for (let key in obj) {
->key : Symbol(key, Decl(keyofAndIndexedAccessErrors.ts, 82, 12))
->obj : Symbol(obj, Decl(keyofAndIndexedAccessErrors.ts, 81, 34))
+    t: T, k: K, tk: T[K], u: U, j: J, uk: U[K], tj: T[J], uj: U[J]): void {
+>t : Symbol(t, Decl(keyofAndIndexedAccessErrors.ts, 81, 60))
+>T : Symbol(T, Decl(keyofAndIndexedAccessErrors.ts, 81, 12))
+>k : Symbol(k, Decl(keyofAndIndexedAccessErrors.ts, 82, 9))
+>K : Symbol(K, Decl(keyofAndIndexedAccessErrors.ts, 81, 14))
+>tk : Symbol(tk, Decl(keyofAndIndexedAccessErrors.ts, 82, 15))
+>T : Symbol(T, Decl(keyofAndIndexedAccessErrors.ts, 81, 12))
+>K : Symbol(K, Decl(keyofAndIndexedAccessErrors.ts, 81, 14))
+>u : Symbol(u, Decl(keyofAndIndexedAccessErrors.ts, 82, 25))
+>U : Symbol(U, Decl(keyofAndIndexedAccessErrors.ts, 81, 33))
+>j : Symbol(j, Decl(keyofAndIndexedAccessErrors.ts, 82, 31))
+>J : Symbol(J, Decl(keyofAndIndexedAccessErrors.ts, 81, 46))
+>uk : Symbol(uk, Decl(keyofAndIndexedAccessErrors.ts, 82, 37))
+>U : Symbol(U, Decl(keyofAndIndexedAccessErrors.ts, 81, 33))
+>K : Symbol(K, Decl(keyofAndIndexedAccessErrors.ts, 81, 14))
+>tj : Symbol(tj, Decl(keyofAndIndexedAccessErrors.ts, 82, 47))
+>T : Symbol(T, Decl(keyofAndIndexedAccessErrors.ts, 81, 12))
+>J : Symbol(J, Decl(keyofAndIndexedAccessErrors.ts, 81, 46))
+>uj : Symbol(uj, Decl(keyofAndIndexedAccessErrors.ts, 82, 57))
+>U : Symbol(U, Decl(keyofAndIndexedAccessErrors.ts, 81, 33))
+>J : Symbol(J, Decl(keyofAndIndexedAccessErrors.ts, 81, 46))
+
+    for (let key in t) {
+>key : Symbol(key, Decl(keyofAndIndexedAccessErrors.ts, 83, 12))
+>t : Symbol(t, Decl(keyofAndIndexedAccessErrors.ts, 81, 60))
+
+        key = k // ok, K ==> keyof T
+>key : Symbol(key, Decl(keyofAndIndexedAccessErrors.ts, 83, 12))
+>k : Symbol(k, Decl(keyofAndIndexedAccessErrors.ts, 82, 9))
 
         k = key // error, keyof T =/=> K
->k : Symbol(k, Decl(keyofAndIndexedAccessErrors.ts, 81, 41))
->key : Symbol(key, Decl(keyofAndIndexedAccessErrors.ts, 82, 12))
+>k : Symbol(k, Decl(keyofAndIndexedAccessErrors.ts, 82, 9))
+>key : Symbol(key, Decl(keyofAndIndexedAccessErrors.ts, 83, 12))
 
-        value = obj[key]; // error, T[keyof T] =/=> T[K]
->value : Symbol(value, Decl(keyofAndIndexedAccessErrors.ts, 81, 47))
->obj : Symbol(obj, Decl(keyofAndIndexedAccessErrors.ts, 81, 34))
->key : Symbol(key, Decl(keyofAndIndexedAccessErrors.ts, 82, 12))
+        t[key] = tk; // ok, T[K] ==> T[keyof T]
+>t : Symbol(t, Decl(keyofAndIndexedAccessErrors.ts, 81, 60))
+>key : Symbol(key, Decl(keyofAndIndexedAccessErrors.ts, 83, 12))
+>tk : Symbol(tk, Decl(keyofAndIndexedAccessErrors.ts, 82, 15))
+
+        tk = t[key]; // error, T[keyof T] =/=> T[K]
+>tk : Symbol(tk, Decl(keyofAndIndexedAccessErrors.ts, 82, 15))
+>t : Symbol(t, Decl(keyofAndIndexedAccessErrors.ts, 81, 60))
+>key : Symbol(key, Decl(keyofAndIndexedAccessErrors.ts, 83, 12))
     }
+    tk = uk;
+>tk : Symbol(tk, Decl(keyofAndIndexedAccessErrors.ts, 82, 15))
+>uk : Symbol(uk, Decl(keyofAndIndexedAccessErrors.ts, 82, 37))
+
+    uk = tk; // error
+>uk : Symbol(uk, Decl(keyofAndIndexedAccessErrors.ts, 82, 37))
+>tk : Symbol(tk, Decl(keyofAndIndexedAccessErrors.ts, 82, 15))
+
+    tj = uj;
+>tj : Symbol(tj, Decl(keyofAndIndexedAccessErrors.ts, 82, 47))
+>uj : Symbol(uj, Decl(keyofAndIndexedAccessErrors.ts, 82, 57))
+
+    uj = tj; // error
+>uj : Symbol(uj, Decl(keyofAndIndexedAccessErrors.ts, 82, 57))
+>tj : Symbol(tj, Decl(keyofAndIndexedAccessErrors.ts, 82, 47))
+
+    tk = tj;
+>tk : Symbol(tk, Decl(keyofAndIndexedAccessErrors.ts, 82, 15))
+>tj : Symbol(tj, Decl(keyofAndIndexedAccessErrors.ts, 82, 47))
+
+    tj = tk; // error
+>tj : Symbol(tj, Decl(keyofAndIndexedAccessErrors.ts, 82, 47))
+>tk : Symbol(tk, Decl(keyofAndIndexedAccessErrors.ts, 82, 15))
+
+    tk = uj;
+>tk : Symbol(tk, Decl(keyofAndIndexedAccessErrors.ts, 82, 15))
+>uj : Symbol(uj, Decl(keyofAndIndexedAccessErrors.ts, 82, 57))
+
+    uj = tk; // error
+>uj : Symbol(uj, Decl(keyofAndIndexedAccessErrors.ts, 82, 57))
+>tk : Symbol(tk, Decl(keyofAndIndexedAccessErrors.ts, 82, 15))
 }
 
-

tests/baselines/reference/keyofAndIndexedAccessErrors.types

@@ -301,35 +301,104 @@ function f20<T, U>(k1: keyof (T | U), k2: keyof (T & U), o1: T | U, o2: T & U) {
 }
 
 // Repro from #17166
-function f3<T, K extends keyof T>(obj: T, k: K, value: T[K]): void {
->f3 : <T, K extends keyof T>(obj: T, k: K, value: T[K]) => void
+function f3<T, K extends keyof T, U extends T, J extends K>(
+>f3 : <T, K extends keyof T, U extends T, J extends K>(t: T, k: K, tk: T[K], u: U, j: J, uk: U[K], tj: T[J], uj: U[J]) => void
 >T : T
 >K : K
 >T : T
->obj : T
+>U : U
+>T : T
+>J : J
+>K : K
+
+    t: T, k: K, tk: T[K], u: U, j: J, uk: U[K], tj: T[J], uj: U[J]): void {
+>t : T
 >T : T
 >k : K
 >K : K
->value : T[K]
+>tk : T[K]
 >T : T
 >K : K
+>u : U
+>U : U
+>j : J
+>J : J
+>uk : U[K]
+>U : U
+>K : K
+>tj : T[J]
+>T : T
+>J : J
+>uj : U[J]
+>U : U
+>J : J
 
-    for (let key in obj) {
+    for (let key in t) {
 >key : keyof T
->obj : T
+>t : T
+
+        key = k // ok, K ==> keyof T
+>key = k : K
+>key : keyof T
+>k : K
 
         k = key // error, keyof T =/=> K
 >k = key : keyof T
 >k : K
 >key : keyof T
 
-        value = obj[key]; // error, T[keyof T] =/=> T[K]
->value = obj[key] : T[keyof T]
->value : T[K]
->obj[key] : T[keyof T]
->obj : T
+        t[key] = tk; // ok, T[K] ==> T[keyof T]
+>t[key] = tk : T[K]
+>t[key] : T[keyof T]
+>t : T
+>key : keyof T
+>tk : T[K]
+
+        tk = t[key]; // error, T[keyof T] =/=> T[K]
+>tk = t[key] : T[keyof T]
+>tk : T[K]
+>t[key] : T[keyof T]
+>t : T
 >key : keyof T
     }
+    tk = uk;
+>tk = uk : U[K]
+>tk : T[K]
+>uk : U[K]
+
+    uk = tk; // error
+>uk = tk : T[K]
+>uk : U[K]
+>tk : T[K]
+
+    tj = uj;
+>tj = uj : U[J]
+>tj : T[J]
+>uj : U[J]
+
+    uj = tj; // error
+>uj = tj : T[J]
+>uj : U[J]
+>tj : T[J]
+
+    tk = tj;
+>tk = tj : T[J]
+>tk : T[K]
+>tj : T[J]
+
+    tj = tk; // error
+>tj = tk : T[K]
+>tj : T[J]
+>tk : T[K]
+
+    tk = uj;
+>tk = uj : U[J]
+>tk : T[K]
+>uj : U[J]
+
+    uj = tk; // error
+>uj = tk : T[K]
+>uj : U[J]
+>tk : T[K]
 }
 
-

tests/baselines/reference/objectBindingPattern_restElementWithPropertyName.errors.txt

@@ -0,0 +1,8 @@
+tests/cases/compiler/objectBindingPattern_restElementWithPropertyName.ts(1,15): error TS2566: A rest element cannot have a property name.
+
+
+==== tests/cases/compiler/objectBindingPattern_restElementWithPropertyName.ts (1 errors) ====
+    const { ...a: b } = {};
+                  ~
+!!! error TS2566: A rest element cannot have a property name.
+    

tests/baselines/reference/objectBindingPattern_restElementWithPropertyName.js

@@ -0,0 +1,15 @@
+//// [objectBindingPattern_restElementWithPropertyName.ts]
+const { ...a: b } = {};
+
+
+//// [objectBindingPattern_restElementWithPropertyName.js]
+var __rest = (this && this.__rest) || function (s, e) {
+    var t = {};
+    for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p) && e.indexOf(p) < 0)
+        t[p] = s[p];
+    if (s != null && typeof Object.getOwnPropertySymbols === "function")
+        for (var i = 0, p = Object.getOwnPropertySymbols(s); i < p.length; i++) if (e.indexOf(p[i]) < 0)
+            t[p[i]] = s[p[i]];
+    return t;
+};
+var b = __rest({}, []);

tests/baselines/reference/objectBindingPattern_restElementWithPropertyName.symbols

@@ -0,0 +1,4 @@
+=== tests/cases/compiler/objectBindingPattern_restElementWithPropertyName.ts ===
+const { ...a: b } = {};
+>b : Symbol(b, Decl(objectBindingPattern_restElementWithPropertyName.ts, 0, 7))
+

tests/baselines/reference/objectBindingPattern_restElementWithPropertyName.types

@@ -0,0 +1,6 @@
+=== tests/cases/compiler/objectBindingPattern_restElementWithPropertyName.ts ===
+const { ...a: b } = {};
+>a : any
+>b : {}
+>{} : {}
+

tests/baselines/reference/quickInfoJsDocTags.baseline

@@ -63,7 +63,7 @@
       ],
       "documentation": [
         {
-          "text": "DocT} A template",
+          "text": "Doc",
           "kind": "text"
         }
       ],
@@ -76,6 +76,10 @@
           "name": "augments",
           "text": "C<T> Augments it"
         },
+        {
+          "name": "template",
+          "text": "{T} A template"
+        },
         {
           "name": "type",
           "text": "{number | string} A type"

tests/baselines/reference/reverseMappedContravariantInference.js

@@ -0,0 +1,11 @@
+//// [reverseMappedContravariantInference.ts]
+// Repro from #21273
+
+declare function conforms<T>(source: { [K in keyof T]: (val: T[K]) => boolean }): (value: T) => boolean;
+conforms({ foo: (v: string) => false })({ foo: "hello" });
+
+
+//// [reverseMappedContravariantInference.js]
+"use strict";
+// Repro from #21273
+conforms({ foo: function (v) { return false; } })({ foo: "hello" });

tests/baselines/reference/reverseMappedContravariantInference.symbols

@@ -0,0 +1,21 @@
+=== tests/cases/compiler/reverseMappedContravariantInference.ts ===
+// Repro from #21273
+
+declare function conforms<T>(source: { [K in keyof T]: (val: T[K]) => boolean }): (value: T) => boolean;
+>conforms : Symbol(conforms, Decl(reverseMappedContravariantInference.ts, 0, 0))
+>T : Symbol(T, Decl(reverseMappedContravariantInference.ts, 2, 26))
+>source : Symbol(source, Decl(reverseMappedContravariantInference.ts, 2, 29))
+>K : Symbol(K, Decl(reverseMappedContravariantInference.ts, 2, 40))
+>T : Symbol(T, Decl(reverseMappedContravariantInference.ts, 2, 26))
+>val : Symbol(val, Decl(reverseMappedContravariantInference.ts, 2, 56))
+>T : Symbol(T, Decl(reverseMappedContravariantInference.ts, 2, 26))
+>K : Symbol(K, Decl(reverseMappedContravariantInference.ts, 2, 40))
+>value : Symbol(value, Decl(reverseMappedContravariantInference.ts, 2, 83))
+>T : Symbol(T, Decl(reverseMappedContravariantInference.ts, 2, 26))
+
+conforms({ foo: (v: string) => false })({ foo: "hello" });
+>conforms : Symbol(conforms, Decl(reverseMappedContravariantInference.ts, 0, 0))
+>foo : Symbol(foo, Decl(reverseMappedContravariantInference.ts, 3, 10))
+>v : Symbol(v, Decl(reverseMappedContravariantInference.ts, 3, 17))
+>foo : Symbol(foo, Decl(reverseMappedContravariantInference.ts, 3, 41))
+

tests/baselines/reference/reverseMappedContravariantInference.types

@@ -0,0 +1,28 @@
+=== tests/cases/compiler/reverseMappedContravariantInference.ts ===
+// Repro from #21273
+
+declare function conforms<T>(source: { [K in keyof T]: (val: T[K]) => boolean }): (value: T) => boolean;
+>conforms : <T>(source: { [K in keyof T]: (val: T[K]) => boolean; }) => (value: T) => boolean
+>T : T
+>source : { [K in keyof T]: (val: T[K]) => boolean; }
+>K : K
+>T : T
+>val : T[K]
+>T : T
+>K : K
+>value : T
+>T : T
+
+conforms({ foo: (v: string) => false })({ foo: "hello" });
+>conforms({ foo: (v: string) => false })({ foo: "hello" }) : boolean
+>conforms({ foo: (v: string) => false }) : (value: { foo: any; }) => boolean
+>conforms : <T>(source: { [K in keyof T]: (val: T[K]) => boolean; }) => (value: T) => boolean
+>{ foo: (v: string) => false } : { foo: (v: string) => boolean; }
+>foo : (v: string) => boolean
+>(v: string) => false : (v: string) => boolean
+>v : string
+>false : false
+>{ foo: "hello" } : { foo: string; }
+>foo : string
+>"hello" : "hello"
+

tests/baselines/reference/strictNullEmptyDestructuring.errors.txt

@@ -0,0 +1,60 @@
+tests/cases/compiler/strictNullEmptyDestructuring.ts(3,5): error TS2531: Object is possibly 'null'.
+tests/cases/compiler/strictNullEmptyDestructuring.ts(5,5): error TS2531: Object is possibly 'null'.
+tests/cases/compiler/strictNullEmptyDestructuring.ts(7,2): error TS2531: Object is possibly 'null'.
+tests/cases/compiler/strictNullEmptyDestructuring.ts(9,5): error TS2532: Object is possibly 'undefined'.
+tests/cases/compiler/strictNullEmptyDestructuring.ts(11,2): error TS2532: Object is possibly 'undefined'.
+tests/cases/compiler/strictNullEmptyDestructuring.ts(13,5): error TS2531: Object is possibly 'null'.
+tests/cases/compiler/strictNullEmptyDestructuring.ts(15,2): error TS2531: Object is possibly 'null'.
+tests/cases/compiler/strictNullEmptyDestructuring.ts(17,5): error TS2532: Object is possibly 'undefined'.
+tests/cases/compiler/strictNullEmptyDestructuring.ts(19,2): error TS2532: Object is possibly 'undefined'.
+tests/cases/compiler/strictNullEmptyDestructuring.ts(21,5): error TS2533: Object is possibly 'null' or 'undefined'.
+tests/cases/compiler/strictNullEmptyDestructuring.ts(23,2): error TS2533: Object is possibly 'null' or 'undefined'.
+
+
+==== tests/cases/compiler/strictNullEmptyDestructuring.ts (11 errors) ====
+    // Repro from #20873
+    
+    let [] = null;
+        ~~
+!!! error TS2531: Object is possibly 'null'.
+    
+    let { } = null;
+        ~~~
+!!! error TS2531: Object is possibly 'null'.
+    
+    ({} = null);
+     ~~
+!!! error TS2531: Object is possibly 'null'.
+    
+    let { } = undefined;
+        ~~~
+!!! error TS2532: Object is possibly 'undefined'.
+    
+    ({} = undefined);
+     ~~
+!!! error TS2532: Object is possibly 'undefined'.
+    
+    let { } = Math.random() ? {} : null;
+        ~~~
+!!! error TS2531: Object is possibly 'null'.
+    
+    ({} = Math.random() ? {} : null);
+     ~~
+!!! error TS2531: Object is possibly 'null'.
+    
+    let { } = Math.random() ? {} : undefined;
+        ~~~
+!!! error TS2532: Object is possibly 'undefined'.
+    
+    ({} = Math.random() ? {} : undefined);
+     ~~
+!!! error TS2532: Object is possibly 'undefined'.
+    
+    let { } = Math.random() ? null : undefined;
+        ~~~
+!!! error TS2533: Object is possibly 'null' or 'undefined'.
+    
+    ({} = Math.random() ? null : undefined);
+     ~~
+!!! error TS2533: Object is possibly 'null' or 'undefined'.
+    

tests/baselines/reference/strictNullEmptyDestructuring.js

@@ -0,0 +1,39 @@
+//// [strictNullEmptyDestructuring.ts]
+// Repro from #20873
+
+let [] = null;
+
+let { } = null;
+
+({} = null);
+
+let { } = undefined;
+
+({} = undefined);
+
+let { } = Math.random() ? {} : null;
+
+({} = Math.random() ? {} : null);
+
+let { } = Math.random() ? {} : undefined;
+
+({} = Math.random() ? {} : undefined);
+
+let { } = Math.random() ? null : undefined;
+
+({} = Math.random() ? null : undefined);
+
+
+//// [strictNullEmptyDestructuring.js]
+// Repro from #20873
+var _a = null;
+var _b = null;
+(null);
+var _c = undefined;
+(undefined);
+var _d = Math.random() ? {} : null;
+(Math.random() ? {} : null);
+var _e = Math.random() ? {} : undefined;
+(Math.random() ? {} : undefined);
+var _f = Math.random() ? null : undefined;
+(Math.random() ? null : undefined);

tests/baselines/reference/strictNullEmptyDestructuring.symbols

@@ -0,0 +1,49 @@
+=== tests/cases/compiler/strictNullEmptyDestructuring.ts ===
+// Repro from #20873
+
+let [] = null;
+
+let { } = null;
+
+({} = null);
+
+let { } = undefined;
+>undefined : Symbol(undefined)
+
+({} = undefined);
+>undefined : Symbol(undefined)
+
+let { } = Math.random() ? {} : null;
+>Math.random : Symbol(Math.random, Decl(lib.d.ts, --, --))
+>Math : Symbol(Math, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --))
+>random : Symbol(Math.random, Decl(lib.d.ts, --, --))
+
+({} = Math.random() ? {} : null);
+>Math.random : Symbol(Math.random, Decl(lib.d.ts, --, --))
+>Math : Symbol(Math, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --))
+>random : Symbol(Math.random, Decl(lib.d.ts, --, --))
+
+let { } = Math.random() ? {} : undefined;
+>Math.random : Symbol(Math.random, Decl(lib.d.ts, --, --))
+>Math : Symbol(Math, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --))
+>random : Symbol(Math.random, Decl(lib.d.ts, --, --))
+>undefined : Symbol(undefined)
+
+({} = Math.random() ? {} : undefined);
+>Math.random : Symbol(Math.random, Decl(lib.d.ts, --, --))
+>Math : Symbol(Math, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --))
+>random : Symbol(Math.random, Decl(lib.d.ts, --, --))
+>undefined : Symbol(undefined)
+
+let { } = Math.random() ? null : undefined;
+>Math.random : Symbol(Math.random, Decl(lib.d.ts, --, --))
+>Math : Symbol(Math, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --))
+>random : Symbol(Math.random, Decl(lib.d.ts, --, --))
+>undefined : Symbol(undefined)
+
+({} = Math.random() ? null : undefined);
+>Math.random : Symbol(Math.random, Decl(lib.d.ts, --, --))
+>Math : Symbol(Math, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --))
+>random : Symbol(Math.random, Decl(lib.d.ts, --, --))
+>undefined : Symbol(undefined)
+

tests/baselines/reference/strictNullEmptyDestructuring.types

@@ -0,0 +1,87 @@
+=== tests/cases/compiler/strictNullEmptyDestructuring.ts ===
+// Repro from #20873
+
+let [] = null;
+>null : null
+
+let { } = null;
+>null : null
+
+({} = null);
+>({} = null) : any
+>{} = null : any
+>{} : {}
+>null : null
+
+let { } = undefined;
+>undefined : undefined
+
+({} = undefined);
+>({} = undefined) : any
+>{} = undefined : any
+>{} : {}
+>undefined : undefined
+
+let { } = Math.random() ? {} : null;
+>Math.random() ? {} : null : {} | null
+>Math.random() : number
+>Math.random : () => number
+>Math : Math
+>random : () => number
+>{} : {}
+>null : null
+
+({} = Math.random() ? {} : null);
+>({} = Math.random() ? {} : null) : {}
+>{} = Math.random() ? {} : null : {}
+>{} : {}
+>Math.random() ? {} : null : {} | null
+>Math.random() : number
+>Math.random : () => number
+>Math : Math
+>random : () => number
+>{} : {}
+>null : null
+
+let { } = Math.random() ? {} : undefined;
+>Math.random() ? {} : undefined : {} | undefined
+>Math.random() : number
+>Math.random : () => number
+>Math : Math
+>random : () => number
+>{} : {}
+>undefined : undefined
+
+({} = Math.random() ? {} : undefined);
+>({} = Math.random() ? {} : undefined) : {}
+>{} = Math.random() ? {} : undefined : {}
+>{} : {}
+>Math.random() ? {} : undefined : {} | undefined
+>Math.random() : number
+>Math.random : () => number
+>Math : Math
+>random : () => number
+>{} : {}
+>undefined : undefined
+
+let { } = Math.random() ? null : undefined;
+>Math.random() ? null : undefined : null | undefined
+>Math.random() : number
+>Math.random : () => number
+>Math : Math
+>random : () => number
+>null : null
+>undefined : undefined
+
+({} = Math.random() ? null : undefined);
+>({} = Math.random() ? null : undefined) : any
+>{} = Math.random() ? null : undefined : any
+>{} : {}
+>Math.random() ? null : undefined : null | undefined
+>Math.random() : number
+>Math.random : () => number
+>Math : Math
+>random : () => number
+>null : null
+>undefined : undefined
+

tests/baselines/reference/user/rxjs.log

@@ -1,11 +1,10 @@
 Exit Code: 1
 Standard output:
-node_modules/rxjs/scheduler/VirtualTimeScheduler.d.ts(22,22): error TS2415: Class 'VirtualAction<T>' incorrectly extends base class 'AsyncAction<T>'.
-  Types of property 'work' are incompatible.
-    Type '(this: VirtualAction<T>, state?: T | undefined) => void' is not assignable to type '(this: AsyncAction<T>, state?: T | undefined) => void'.
-      The 'this' types of each signature are incompatible.
-        Type 'AsyncAction<T>' is not assignable to type 'VirtualAction<T>'.
-          Property 'index' is missing in type 'AsyncAction<T>'.
+node_modules/rxjs/scheduler/VirtualTimeScheduler.d.ts(24,15): error TS2416: Property 'work' in type 'VirtualAction<T>' is not assignable to the same property in base type 'AsyncAction<T>'.
+  Type '(this: VirtualAction<T>, state?: T | undefined) => void' is not assignable to type '(this: AsyncAction<T>, state?: T | undefined) => void'.
+    The 'this' types of each signature are incompatible.
+      Type 'AsyncAction<T>' is not assignable to type 'VirtualAction<T>'.
+        Property 'index' is missing in type 'AsyncAction<T>'.
 
 
 

tests/baselines/reference/user/sift.log

@@ -0,0 +1,8 @@
+Exit Code: 1
+Standard output:
+node_modules/sift/index.d.ts(22,54): error TS2344: Type 'T[0][index]' does not satisfy the constraint 'any[]'.
+node_modules/sift/index.d.ts(32,35): error TS2344: Type 'T[0][P]' does not satisfy the constraint 'any[]'.
+
+
+
+Standard error:

tests/cases/compiler/inferObjectTypeFromStringLiteralToKeyof.ts

@@ -1,3 +1,5 @@
-declare function inference<T>(target: T, name: keyof T): void;
+declare function inference1<T>(name: keyof T): T;
+declare function inference2<T>(target: T, name: keyof T): T;
 declare var two: "a" | "d";
-inference({ a: 1, b: 2, c: 3, d(n) { return n } }, two);
+const x = inference1(two);
+const y = inference2({ a: 1, b: 2, c: 3, d(n) { return n } }, two);

tests/cases/compiler/objectBindingPattern_restElementWithPropertyName.ts

@@ -0,0 +1 @@
+const { ...a: b } = {};

tests/cases/compiler/reverseMappedContravariantInference.ts

@@ -0,0 +1,6 @@
+// @strict: true
+
+// Repro from #21273
+
+declare function conforms<T>(source: { [K in keyof T]: (val: T[K]) => boolean }): (value: T) => boolean;
+conforms({ foo: (v: string) => false })({ foo: "hello" });

tests/cases/compiler/strictNullEmptyDestructuring.ts

@@ -0,0 +1,25 @@
+// @strictNullChecks: true
+
+// Repro from #20873
+
+let [] = null;
+
+let { } = null;
+
+({} = null);
+
+let { } = undefined;
+
+({} = undefined);
+
+let { } = Math.random() ? {} : null;
+
+({} = Math.random() ? {} : null);
+
+let { } = Math.random() ? {} : undefined;
+
+({} = Math.random() ? {} : undefined);
+
+let { } = Math.random() ? null : undefined;
+
+({} = Math.random() ? null : undefined);

tests/cases/conformance/types/keyof/keyofAndIndexedAccess.ts

@@ -554,3 +554,16 @@ class AnotherSampleClass<T> extends SampleClass<T & Foo> {
     }
 }
 new AnotherSampleClass({});
+
+// Positive repro from #17166
+function f3<T, K extends keyof T>(t: T, k: K, tk: T[K]): void {
+    for (let key in t) {
+        key = k // ok, K ==> keyof T
+        t[key] = tk; // ok, T[K] ==> T[keyof T]
+    }
+}
+
+// # 21185
+type Predicates<TaggedRecord> = {
+  [T in keyof TaggedRecord]: (variant: TaggedRecord[keyof TaggedRecord]) => variant is TaggedRecord[T]
+}

tests/cases/conformance/types/keyof/keyofAndIndexedAccessErrors.ts

@@ -79,10 +79,23 @@ function f20<T, U>(k1: keyof (T | U), k2: keyof (T & U), o1: T | U, o2: T & U) {
 }
 
 // Repro from #17166
-function f3<T, K extends keyof T>(obj: T, k: K, value: T[K]): void {
-    for (let key in obj) {
+function f3<T, K extends keyof T, U extends T, J extends K>(
+    t: T, k: K, tk: T[K], u: U, j: J, uk: U[K], tj: T[J], uj: U[J]): void {
+    for (let key in t) {
+        key = k // ok, K ==> keyof T
         k = key // error, keyof T =/=> K
-        value = obj[key]; // error, T[keyof T] =/=> T[K]
+        t[key] = tk; // ok, T[K] ==> T[keyof T]
+        tk = t[key]; // error, T[keyof T] =/=> T[K]
     }
-}
+    tk = uk;
+    uk = tk; // error
 
+    tj = uj;
+    uj = tj; // error
+
+    tk = tj;
+    tj = tk; // error
+
+    tk = uj;
+    uj = tk; // error
+}

tests/cases/fourslash/autoFormattingOnPasting.ts

@@ -11,12 +11,12 @@ public testMethod( )
 }`);
 // We're missing scenarios of formatting option settings due to bug 693273 - [TypeScript] Need to improve fourslash support for formatting options.
 // Missing scenario ** Uncheck Tools->Options->Text Editor->TypeScript->Formatting->General->Format on paste **
-//verify.currentFileContentIs("module TestModule {\r\n\
-// class TestClass{\r\n\
-//private   foo;\r\n\
-//public testMethod( )\r\n\
-//{}\r\n\
-//}\r\n\
+//verify.currentFileContentIs("module TestModule {\n\
+// class TestClass{\n\
+//private   foo;\n\
+//public testMethod( )\n\
+//{}\n\
+//}\n\
 //}");
 // Missing scenario ** Check Tools->Options->Text Editor->TypeScript->Formatting->General->Format on paste **
 verify.currentFileContentIs(`module TestModule {

tests/cases/fourslash/classInterfaceInsert.ts

@@ -12,6 +12,6 @@
 verify.quickInfoAt("className", "class Sphere");
 
 goTo.marker('interfaceGoesHere');
-edit.insert("\r\ninterface Surface {\r\n    reflect: () => number;\r\n}\r\n");
+edit.insert("\ninterface Surface {\n    reflect: () => number;\n}\n");
 
 verify.quickInfoAt("className", "class Sphere");

tests/cases/fourslash/codeFixAddMissingMember.ts

@@ -9,9 +9,8 @@
 verify.codeFix({
     description: "Declare property 'foo'",
     index: 0,
-    // TODO: GH#18445
     newFileContent: `class C {
-    foo: number;\r
+    foo: number;
     method() {
         this.foo = 10;
     }

tests/cases/fourslash/codeFixAddMissingMember2.ts

@@ -9,9 +9,8 @@
 verify.codeFix({
     description: "Add index signature for property 'foo'",
     index: 1,
-    // TODO: GH#18445
     newFileContent: `class C {
-    [x: string]: number;\r
+    [x: string]: number;
     method() {
         this.foo = 10;
     }

tests/cases/fourslash/codeFixAddMissingMember3.ts

@@ -9,9 +9,8 @@
 verify.codeFix({
     description: "Declare static property 'foo'",
     index: 0,
-    // TODO: GH#18445
     newFileContent: `class C {
-    static foo: number;\r
+    static foo: number;
     static method() {
         this.foo = 10;
     }

tests/cases/fourslash/codeFixAddMissingMember4.ts

@@ -15,10 +15,9 @@
 verify.codeFix({
     description: "Initialize property 'foo' in the constructor",
     index: 0,
-    // TODO: GH#18445
     newFileContent: `class C {
-    constructor() {\r
-        this.foo = undefined;\r
+    constructor() {
+        this.foo = undefined;
     }
     method() {
         this.foo === 10;

tests/cases/fourslash/codeFixAddMissingMember5.ts

@@ -13,12 +13,11 @@
 verify.codeFix({
     description: "Initialize static property 'foo'",
     index: 0,
-    // TODO: GH#18445
     newFileContent: `class C {
     static method() {
         ()=>{ this.foo === 10 };
     }
-}\r
-C.foo = undefined;\r
+}
+C.foo = undefined;
 `
 });

tests/cases/fourslash/codeFixAddMissingMember6.ts

@@ -13,10 +13,9 @@
 verify.codeFix({
     description: "Initialize property 'foo' in the constructor",
     index: 0,
-    // TODO: GH#18445
     newFileContent: `class C {
-    constructor() {\r
-        this.foo = undefined;\r
+    constructor() {
+        this.foo = undefined;
     }
     prop = ()=>{ this.foo === 10 };
 }`

tests/cases/fourslash/codeFixAddMissingMember7.ts

@@ -11,10 +11,9 @@
 verify.codeFix({
     description: "Initialize static property 'foo'",
     index: 2,
-    // TODO: GH#18445
     newFileContent: `class C {
     static p = ()=>{ this.foo === 10 };
-}\r
-C.foo = undefined;\r
+}
+C.foo = undefined;
 `
 });

tests/cases/fourslash/codeFixAddMissingMember_all.ts

@@ -11,12 +11,11 @@
 verify.codeFixAll({
     fixId: "addMissingMember",
     newFileContent:
-    // TODO: GH#18445
 `class C {
-    x: number;\r
-    y(): any {\r
-        throw new Error("Method not implemented.");\r
-    }\r
+    x: number;
+    y(): any {
+        throw new Error("Method not implemented.");
+    }
     method() {
         this.x = 0;
         this.y();

tests/cases/fourslash/codeFixAddMissingMember_all_js.ts

@@ -16,13 +16,12 @@
 verify.codeFixAll({
     fixId: "addMissingMember",
     newFileContent:
-    // TODO: GH#18445
 `class C {
-    y() {\r
-        throw new Error("Method not implemented.");\r
-    }\r
-    constructor() {\r
-        this.x = undefined;\r
+    y() {
+        throw new Error("Method not implemented.");
+    }
+    constructor() {
+        this.x = undefined;
     }
     method() {
         this.x;

tests/cases/fourslash/codeFixClassExprClassImplementClassFunctionVoidInferred.ts

@@ -12,9 +12,9 @@ verify.codeFix({
 `class A {
     f() {}
 }
-let B = class implements A {\r
-    f(): void {\r
-        throw new Error("Method not implemented.");\r
-    }\r
+let B = class implements A {
+    f(): void {
+        throw new Error("Method not implemented.");
+    }
 }`
 });

tests/cases/fourslash/codeFixClassExprExtendsAbstractExpressionWithTypeArgs.ts

@@ -20,7 +20,7 @@ verify.codeFix({
     return C;
 }
 
-let B = class extends foo("s")<number> {\r
-    a: string | number;\r
+let B = class extends foo("s")<number> {
+    a: string | number;
 }`
 });

tests/cases/fourslash/codeFixClassExtendAbstractExpressionWithTypeArgs.ts

@@ -20,7 +20,7 @@ verify.codeFix({
     return C;
 }
 
-class B extends foo("s")<number> {\r
-    a: string | number;\r
+class B extends foo("s")<number> {
+    a: string | number;
 }`
 });

tests/cases/fourslash/codeFixClassExtendAbstractGetterSetter.ts

@@ -42,13 +42,13 @@ verify.codeFix({
 // Don't need to add anything in this case.
 abstract class B extends A {}
 
-class C extends A {\r
-    a: string | number;\r
-    b: this;\r
-    c: A;\r
-    d: string | number;\r
-    e: this;\r
-    f: A;\r
-    g: string;\r
+class C extends A {
+    a: string | number;
+    b: this;
+    c: A;
+    d: string | number;
+    e: this;
+    f: A;
+    g: string;
 }`
 });

tests/cases/fourslash/codeFixClassExtendAbstractMethod.ts

@@ -22,16 +22,16 @@ verify.codeFix({
     abstract foo(): number;
 }
 
-class C extends A {\r
-    f(a: number, b: string): boolean;\r
-    f(a: number, b: string): this;\r
-    f(a: string, b: number): Function;\r
-    f(a: string): Function;\r
-    f(a: any, b?: any) {\r
-        throw new Error("Method not implemented.");\r
-    }\r
-    foo(): number {\r
-        throw new Error("Method not implemented.");\r
-    }\r
+class C extends A {
+    f(a: number, b: string): boolean;
+    f(a: number, b: string): this;
+    f(a: string, b: number): Function;
+    f(a: string): Function;
+    f(a: any, b?: any) {
+        throw new Error("Method not implemented.");
+    }
+    foo(): number {
+        throw new Error("Method not implemented.");
+    }
 }`
 });

tests/cases/fourslash/codeFixClassExtendAbstractMethodThis.ts

@@ -14,9 +14,9 @@ verify.codeFix({
     abstract f(): this;
 }
 
-class C extends A {\r
-    f(): this {\r
-        throw new Error("Method not implemented.");\r
-    }\r
+class C extends A {
+    f(): this {
+        throw new Error("Method not implemented.");
+    }
 }`
 });

tests/cases/fourslash/codeFixClassExtendAbstractMethodTypeParamsInstantiateNumber.ts

@@ -14,9 +14,9 @@ verify.codeFix({
     abstract f(x: T): T;
 }
 
-class C extends A<number> {\r
-    f(x: number): number {\r
-        throw new Error("Method not implemented.");\r
-    }\r
+class C extends A<number> {
+    f(x: number): number {
+        throw new Error("Method not implemented.");
+    }
 }`
 });

tests/cases/fourslash/codeFixClassExtendAbstractMethodTypeParamsInstantiateU.ts

@@ -14,9 +14,9 @@ verify.codeFix({
     abstract f(x: T): T;
 }
 
-class C<U> extends A<U> {\r
-    f(x: U): U {\r
-        throw new Error("Method not implemented.");\r
-    }\r
+class C<U> extends A<U> {
+    f(x: U): U {
+        throw new Error("Method not implemented.");
+    }
 }`
 });

tests/cases/fourslash/codeFixClassExtendAbstractMethod_all.ts

@@ -8,19 +8,18 @@
 
 verify.codeFixAll({
     fixId: "fixClassDoesntImplementInheritedAbstractMember",
-    // TODO: GH#18445
     newFileContent:
 `abstract class A {
     abstract m(): void;
 }
-class B extends A {\r
-    m(): void {\r
-        throw new Error("Method not implemented.");\r
-    }\r
+class B extends A {
+    m(): void {
+        throw new Error("Method not implemented.");
+    }
 }
-class C extends A {\r
-    m(): void {\r
-        throw new Error("Method not implemented.");\r
-    }\r
+class C extends A {
+    m(): void {
+        throw new Error("Method not implemented.");
+    }
 }`,
 });

tests/cases/fourslash/codeFixClassExtendAbstractProperty.ts

@@ -18,9 +18,9 @@ verify.codeFix({
     abstract z: A;
 }
 
-class C extends A {\r
-    x: number;\r
-    y: this;\r
-    z: A;\r
+class C extends A {
+    x: number;
+    y: this;
+    z: A;
 }`
 });