Merge branch 'main' into staleErrors

Author: sheetalkamat

src/compiler/checker.ts

@@ -26519,7 +26519,7 @@ namespace ts {
                 if (result) {
                     return result;
                 }
-                if (!(contextFlags! & ContextFlags.SkipBindingPatterns) && isBindingPattern(declaration.name)) { // This is less a contextual type and more an implied shape - in some cases, this may be undesirable
+                if (!(contextFlags! & ContextFlags.SkipBindingPatterns) && isBindingPattern(declaration.name) && declaration.name.elements.length > 0) {
                     return getTypeFromBindingPattern(declaration.name, /*includePatternInType*/ true, /*reportErrors*/ false);
                 }
             }
@@ -27053,22 +27053,20 @@ namespace ts {
                 const inferenceContext = getInferenceContext(node);
                 // If no inferences have been made, nothing is gained from instantiating as type parameters
                 // would just be replaced with their defaults similar to the apparent type.
-                if (inferenceContext && some(inferenceContext.inferences, hasInferenceCandidates)) {
+                if (inferenceContext && contextFlags! & ContextFlags.Signature && some(inferenceContext.inferences, hasInferenceCandidates)) {
                     // For contextual signatures we incorporate all inferences made so far, e.g. from return
                     // types as well as arguments to the left in a function call.
-                    if (contextFlags && contextFlags & ContextFlags.Signature) {
-                        return instantiateInstantiableTypes(contextualType, inferenceContext.nonFixingMapper);
-                    }
+                    return instantiateInstantiableTypes(contextualType, inferenceContext.nonFixingMapper);
+                }
+                if (inferenceContext?.returnMapper) {
                     // For other purposes (e.g. determining whether to produce literal types) we only
                     // incorporate inferences made from the return type in a function call. We remove
                     // the 'boolean' type from the contextual type such that contextually typed boolean
                     // literals actually end up widening to 'boolean' (see #48363).
-                    if (inferenceContext.returnMapper) {
-                        const type = instantiateInstantiableTypes(contextualType, inferenceContext.returnMapper);
-                        return type.flags & TypeFlags.Union && containsType((type as UnionType).types, regularFalseType) && containsType((type as UnionType).types, regularTrueType) ?
-                            filterType(type, t => t !== regularFalseType && t !== regularTrueType) :
-                            type;
-                    }
+                    const type = instantiateInstantiableTypes(contextualType, inferenceContext.returnMapper);
+                    return type.flags & TypeFlags.Union && containsType((type as UnionType).types, regularFalseType) && containsType((type as UnionType).types, regularTrueType) ?
+                        filterType(type, t => t !== regularFalseType && t !== regularTrueType) :
+                        type;
                 }
             }
             return contextualType;
@@ -29904,29 +29902,43 @@ namespace ts {
             // 'let f: (x: string) => number = wrap(s => s.length)', we infer from the declared type of 'f' to the
             // return type of 'wrap'.
             if (node.kind !== SyntaxKind.Decorator) {
-                const contextualType = getContextualType(node, every(signature.typeParameters, p => !!getDefaultFromTypeParameter(p)) ? ContextFlags.SkipBindingPatterns : ContextFlags.None);
+                const skipBindingPatterns = every(signature.typeParameters, p => !!getDefaultFromTypeParameter(p));
+                const contextualType = getContextualType(node, skipBindingPatterns ? ContextFlags.SkipBindingPatterns : ContextFlags.None);
                 if (contextualType) {
                     const inferenceTargetType = getReturnTypeOfSignature(signature);
                     if (couldContainTypeVariables(inferenceTargetType)) {
-                        // We clone the inference context to avoid disturbing a resolution in progress for an
-                        // outer call expression. Effectively we just want a snapshot of whatever has been
-                        // inferred for any outer call expression so far.
                         const outerContext = getInferenceContext(node);
-                        const outerMapper = getMapperFromContext(cloneInferenceContext(outerContext, InferenceFlags.NoDefault));
-                        const instantiatedType = instantiateType(contextualType, outerMapper);
-                        // If the contextual type is a generic function type with a single call signature, we
-                        // instantiate the type with its own type parameters and type arguments. This ensures that
-                        // the type parameters are not erased to type any during type inference such that they can
-                        // be inferred as actual types from the contextual type. For example:
-                        //   declare function arrayMap<T, U>(f: (x: T) => U): (a: T[]) => U[];
-                        //   const boxElements: <A>(a: A[]) => { value: A }[] = arrayMap(value => ({ value }));
-                        // Above, the type of the 'value' parameter is inferred to be 'A'.
-                        const contextualSignature = getSingleCallSignature(instantiatedType);
-                        const inferenceSourceType = contextualSignature && contextualSignature.typeParameters ?
-                            getOrCreateTypeFromSignature(getSignatureInstantiationWithoutFillingInTypeArguments(contextualSignature, contextualSignature.typeParameters)) :
-                            instantiatedType;
-                        // Inferences made from return types have lower priority than all other inferences.
-                        inferTypes(context.inferences, inferenceSourceType, inferenceTargetType, InferencePriority.ReturnType);
+                        const isFromBindingPattern = !skipBindingPatterns && getContextualType(node, ContextFlags.SkipBindingPatterns) !== contextualType;
+                        // A return type inference from a binding pattern can be used in instantiating the contextual
+                        // type of an argument later in inference, but cannot stand on its own as the final return type.
+                        // It is incorporated into `context.returnMapper` which is used in `instantiateContextualType`,
+                        // but doesn't need to go into `context.inferences`. This allows a an array binding pattern to
+                        // produce a tuple for `T` in
+                        //   declare function f<T>(cb: () => T): T;
+                        //   const [e1, e2, e3] = f(() => [1, "hi", true]);
+                        // but does not produce any inference for `T` in
+                        //   declare function f<T>(): T;
+                        //   const [e1, e2, e3] = f();
+                        if (!isFromBindingPattern) {
+                            // We clone the inference context to avoid disturbing a resolution in progress for an
+                            // outer call expression. Effectively we just want a snapshot of whatever has been
+                            // inferred for any outer call expression so far.
+                            const outerMapper = getMapperFromContext(cloneInferenceContext(outerContext, InferenceFlags.NoDefault));
+                            const instantiatedType = instantiateType(contextualType, outerMapper);
+                            // If the contextual type is a generic function type with a single call signature, we
+                            // instantiate the type with its own type parameters and type arguments. This ensures that
+                            // the type parameters are not erased to type any during type inference such that they can
+                            // be inferred as actual types from the contextual type. For example:
+                            //   declare function arrayMap<T, U>(f: (x: T) => U): (a: T[]) => U[];
+                            //   const boxElements: <A>(a: A[]) => { value: A }[] = arrayMap(value => ({ value }));
+                            // Above, the type of the 'value' parameter is inferred to be 'A'.
+                            const contextualSignature = getSingleCallSignature(instantiatedType);
+                            const inferenceSourceType = contextualSignature && contextualSignature.typeParameters ?
+                                getOrCreateTypeFromSignature(getSignatureInstantiationWithoutFillingInTypeArguments(contextualSignature, contextualSignature.typeParameters)) :
+                                instantiatedType;
+                            // Inferences made from return types have lower priority than all other inferences.
+                            inferTypes(context.inferences, inferenceSourceType, inferenceTargetType, InferencePriority.ReturnType);
+                        }
                         // Create a type mapper for instantiating generic contextual types using the inferences made
                         // from the return type. We need a separate inference pass here because (a) instantiation of
                         // the source type uses the outer context's return mapper (which excludes inferences made from

src/compiler/commandLineParser.ts

@@ -3548,7 +3548,7 @@ namespace ts {
         }
         if (isImplicitGlob(spec.substring(spec.lastIndexOf(directorySeparator) + 1))) {
             return {
-                key: useCaseSensitiveFileNames ? spec : toFileNameLowerCase(spec),
+                key: removeTrailingDirectorySeparator(useCaseSensitiveFileNames ? spec : toFileNameLowerCase(spec)),
                 flags: WatchDirectoryFlags.Recursive
             };
         }

src/compiler/transformers/module/esnextAnd2015.ts

@@ -72,7 +72,7 @@ namespace ts {
                     // Though an error in es2020 modules, in node-flavor es2020 modules, we can helpfully transform this to a synthetic `require` call
                     // To give easy access to a synchronous `require` in node-flavor esm. We do the transform even in scenarios where we error, but `import.meta.url`
                     // is available, just because the output is reasonable for a node-like runtime.
-                    return getEmitScriptTarget(compilerOptions) >= ModuleKind.ES2020 ? visitImportEqualsDeclaration(node as ImportEqualsDeclaration) : undefined;
+                    return getEmitModuleKind(compilerOptions) >= ModuleKind.Node16 ? visitImportEqualsDeclaration(node as ImportEqualsDeclaration) : undefined;
                 case SyntaxKind.ExportAssignment:
                     return visitExportAssignment(node as ExportAssignment);
                 case SyntaxKind.ExportDeclaration:

src/compiler/types.ts

@@ -5874,7 +5874,7 @@ namespace ts {
         ReturnType                   = 1 << 7,  // Inference made from return type of generic function
         LiteralKeyof                 = 1 << 8,  // Inference made from a string literal to a keyof T
         NoConstraints                = 1 << 9,  // Don't infer from constraints of instantiable types
-        AlwaysStrict                 = 1 << 10,  // Always use strict rules for contravariant inferences
+        AlwaysStrict                 = 1 << 10, // Always use strict rules for contravariant inferences
         MaxValue                     = 1 << 11, // Seed for inference priority tracking
 
         PriorityImpliesCombination = ReturnType | MappedTypeConstraint | LiteralKeyof,  // These priorities imply that the resulting type should be a combination of all candidates
@@ -8813,6 +8813,7 @@ namespace ts {
         readonly includeInlayParameterNameHintsWhenArgumentMatchesName?: boolean;
         readonly includeInlayFunctionParameterTypeHints?: boolean,
         readonly includeInlayVariableTypeHints?: boolean;
+        readonly includeInlayVariableTypeHintsWhenTypeMatchesName?: boolean;
         readonly includeInlayPropertyDeclarationTypeHints?: boolean;
         readonly includeInlayFunctionLikeReturnTypeHints?: boolean;
         readonly includeInlayEnumMemberValueHints?: boolean;

src/compiler/watchPublic.ts

@@ -700,6 +700,7 @@ namespace ts {
 
         function reloadFileNamesFromConfigFile() {
             writeLog("Reloading new file names and options");
+            reloadLevel = ConfigFileProgramReloadLevel.None;
             rootFileNames = getFileNamesFromConfigSpecs(compilerOptions.configFile!.configFileSpecs!, getNormalizedAbsolutePath(getDirectoryPath(configFileName), currentDirectory), compilerOptions, parseConfigFileHost, extraFileExtensions);
             if (updateErrorForNoInputFiles(rootFileNames, getNormalizedAbsolutePath(configFileName, currentDirectory), compilerOptions.configFile!.configFileSpecs!, configFileParsingDiagnostics!, canConfigFileJsonReportNoInputFiles)) {
                 hasChangedConfigFileParsingErrors = true;

src/harness/fourslashInterfaceImpl.ts

@@ -1498,6 +1498,7 @@ namespace FourSlashInterface {
             "throw",
             "true",
             "try",
+            "type",
             "typeof",
             "var",
             "void",
@@ -1649,6 +1650,7 @@ namespace FourSlashInterface {
             "throw",
             "true",
             "try",
+            "type",
             "typeof",
             "var",
             "void",

src/server/protocol.ts

@@ -728,7 +728,7 @@ namespace ts.server.protocol {
     }
 
     // All we need is the `success` and `message` fields of Response.
-    export interface ApplyCodeActionCommandResponse extends Response {}
+    export interface ApplyCodeActionCommandResponse extends Response { }
 
     export interface FileRangeRequestArgs extends FileRequestArgs {
         /**
@@ -1067,7 +1067,7 @@ namespace ts.server.protocol {
         readonly arguments: JsxClosingTagRequestArgs;
     }
 
-    export interface JsxClosingTagRequestArgs extends FileLocationRequestArgs {}
+    export interface JsxClosingTagRequestArgs extends FileLocationRequestArgs { }
 
     export interface JsxClosingTagResponse extends Response {
         readonly body: TextInsertion;
@@ -2390,7 +2390,7 @@ namespace ts.server.protocol {
         /**
          * Human-readable description of the `source` from the CompletionEntry.
          */
-         sourceDisplay?: SymbolDisplayPart[];
+        sourceDisplay?: SymbolDisplayPart[];
     }
 
     /** @deprecated Prefer CompletionInfoResponse, which supports several top-level fields in addition to the array of entries. */
@@ -3415,7 +3415,7 @@ namespace ts.server.protocol {
         /**
          * Allows completions to be formatted with snippet text, indicated by `CompletionItem["isSnippet"]`.
          */
-         readonly includeCompletionsWithSnippetText?: boolean;
+        readonly includeCompletionsWithSnippetText?: boolean;
         /**
          * If enabled, the completion list will include completions with invalid identifier names.
          * For those entries, The `insertText` and `replacementSpan` properties will be set to change from `.x` property access to `["x"]`.
@@ -3465,6 +3465,7 @@ namespace ts.server.protocol {
         readonly includeInlayParameterNameHintsWhenArgumentMatchesName?: boolean;
         readonly includeInlayFunctionParameterTypeHints?: boolean,
         readonly includeInlayVariableTypeHints?: boolean;
+        readonly includeInlayVariableTypeHintsWhenTypeMatchesName?: boolean;
         readonly includeInlayPropertyDeclarationTypeHints?: boolean;
         readonly includeInlayFunctionLikeReturnTypeHints?: boolean;
         readonly includeInlayEnumMemberValueHints?: boolean;

src/services/completions.ts

@@ -3988,6 +3988,7 @@ namespace ts.Completions {
         return kind === SyntaxKind.AsyncKeyword
             || kind === SyntaxKind.AwaitKeyword
             || kind === SyntaxKind.AsKeyword
+            || kind === SyntaxKind.TypeKeyword
             || !isContextualKeyword(kind) && !isClassMemberCompletionKeyword(kind);
     }
 

src/services/inlayHints.ts

@@ -137,6 +137,10 @@ namespace ts.InlayHints {
 
             const typeDisplayString = printTypeInSingleLine(declarationType);
             if (typeDisplayString) {
+                const isVariableNameMatchesType = preferences.includeInlayVariableTypeHintsWhenTypeMatchesName === false && equateStringsCaseInsensitive(decl.name.getText(), typeDisplayString);
+                if (isVariableNameMatchesType) {
+                    return;
+                }
                 addTypeHints(typeDisplayString, decl.name.end);
             }
         }

src/testRunner/unittests/config/tsconfigParsing.ts

@@ -421,5 +421,14 @@ namespace ts {
             const parsedCommand = parseJsonConfigFileContent(parsed.config, sys, "/foo.bar");
             assert.deepEqual(parsedCommand.wildcardDirectories, { "/foo.bar/src": WatchDirectoryFlags.Recursive });
         });
+
+        it("correctly parses wild card directories from implicit glob when two keys differ only in directory seperator", () => {
+            const parsed = parseConfigFileTextToJson("/foo.bar/tsconfig.json", JSON.stringify({
+                include: ["./", "./**/*.json"]
+            }));
+
+            const parsedCommand = parseJsonConfigFileContent(parsed.config, sys, "/foo");
+            assert.deepEqual(parsedCommand.wildcardDirectories, { "/foo": WatchDirectoryFlags.Recursive });
+        });
     });
 }

src/testRunner/unittests/tscWatch/programUpdates.ts

@@ -616,6 +616,39 @@ export class A {
             ]
         });
 
+        verifyTscWatch({
+            scenario,
+            subScenario: "correctly parses wild card directories from implicit glob when two keys differ only in directory seperator",
+            commandLineArgs: ["-w", "--extendedDiagnostics"],
+            sys: () => {
+                const file1 = {
+                    path: `${projectRoot}/f1.ts`,
+                    content: "export const x = 1"
+                };
+                const file2 = {
+                    path: `${projectRoot}/f2.ts`,
+                    content: "export const y = 1"
+                };
+                const configFile = {
+                    path: `${projectRoot}/tsconfig.json`,
+                    content: JSON.stringify({ compilerOptions: { composite: true }, include: ["./", "./**/*.json"] })
+                };
+                return createWatchedSystem([file1, file2, libFile, configFile], { currentDirectory: projectRoot });
+            },
+            changes: [
+                {
+                    caption: "Add new file",
+                    change: sys => sys.writeFile(`${projectRoot}/new-file.ts`, "export const z = 1;"),
+                    timeouts: sys => sys.checkTimeoutQueueLengthAndRun(1),
+                },
+                {
+                    caption: "Import new file",
+                    change: sys => sys.prependFile(`${projectRoot}/f1.ts`, `import { z } from "./new-file";`),
+                    timeouts: sys => sys.checkTimeoutQueueLengthAndRun(1),
+                }
+            ]
+        });
+
         verifyTscWatch({
             scenario,
             subScenario: "can correctly update configured project when set of root files has changed through include",