Support code-fix-all for importFixes

src/compiler/core.ts

@@ -531,7 +531,7 @@ namespace ts {
         return result;
     }
 
-    export function flatMapIterator<T, U>(iter: Iterator<T>, mapfn: (x: T) => U[] | Iterator<U> | undefined): Iterator<U> {
+    export function flatMapIterator<T, U>(iter: Iterator<T>, mapfn: (x: T) => ReadonlyArray<U> | Iterator<U> | undefined): Iterator<U> {
         const first = iter.next();
         if (first.done) {
             return emptyIterator;
@@ -1418,7 +1418,9 @@ namespace ts {
         return typeof text === "string";
     }
 
-    export function tryCast<TOut extends TIn, TIn = any>(value: TIn | undefined, test: (value: TIn) => value is TOut): TOut | undefined {
+    export function tryCast<TOut extends TIn, TIn = any>(value: TIn | undefined, test: (value: TIn) => value is TOut): TOut | undefined;
+    export function tryCast<T>(value: T, test: (value: T) => boolean): T | undefined;
+    export function tryCast<T>(value: T, test: (value: T) => boolean): T | undefined {
         return value !== undefined && test(value) ? value : undefined;
     }
 

src/compiler/diagnosticMessages.json

@@ -4470,5 +4470,9 @@
     "Add missing enum member '{0}'": {
         "category": "Message",
         "code": 95063
+    },
+    "Add all missing imports": {
+        "category": "Message",
+        "code": 95064
     }
 }

src/compiler/utilities.ts

@@ -4312,8 +4312,8 @@ namespace ts {
         return !!forEachAncestorDirectory(directory, d => callback(d) ? true : undefined);
     }
 
-    export function isUMDExportSymbol(symbol: Symbol | undefined) {
-        return symbol && symbol.declarations && symbol.declarations[0] && isNamespaceExportDeclaration(symbol.declarations[0]);
+    export function isUMDExportSymbol(symbol: Symbol | undefined): boolean {
+        return !!symbol && !!symbol.declarations && !!symbol.declarations[0] && isNamespaceExportDeclaration(symbol.declarations[0]);
     }
 
     export function showModuleSpecifier({ moduleSpecifier }: ImportDeclaration): string {
@@ -8105,4 +8105,6 @@ namespace ts {
 
         return findBestPatternMatch(patterns, _ => _, candidate);
     }
+
+    export type Mutable<T extends object> = { -readonly [K in keyof T]: T[K] };
 }

src/harness/fourslash.ts

@@ -2631,7 +2631,7 @@ Actual: ${stringify(fullActual)}`);
             }
             const range = ts.firstOrUndefined(ranges);
 
-            const codeFixes = this.getCodeFixes(fileName, errorCode, preferences).filter(f => f.fixId === undefined); // TODO: GH#20315 filter out those that use the import fix ID;
+            const codeFixes = this.getCodeFixes(fileName, errorCode, preferences).filter(f => f.fixId === ts.codefix.importFixId);
 
             if (codeFixes.length === 0) {
                 if (expectedTextArray.length !== 0) {

src/services/codeFixProvider.ts

@@ -1,9 +1,9 @@
 /* @internal */
 namespace ts {
     export interface CodeFixRegistration {
-        errorCodes: number[];
+        errorCodes: ReadonlyArray<number>;
         getCodeActions(context: CodeFixContext): CodeFixAction[] | undefined;
-        fixIds?: string[];
+        fixIds?: ReadonlyArray<string>;
         getAllCodeActions?(context: CodeFixAllContext): CombinedCodeActions;
     }
 
@@ -27,7 +27,7 @@ namespace ts {
         const errorCodeToFixes = createMultiMap<CodeFixRegistration>();
         const fixIdToRegistration = createMap<CodeFixRegistration>();
 
-        type DiagnosticAndArguments = DiagnosticMessage | [DiagnosticMessage, string] | [DiagnosticMessage, string, string];
+        export type DiagnosticAndArguments = DiagnosticMessage | [DiagnosticMessage, string] | [DiagnosticMessage, string, string];
         function diagnosticToString(diag: DiagnosticAndArguments): string {
             return isArray(diag)
                 ? formatStringFromArgs(getLocaleSpecificMessage(diag[0]), diag.slice(1) as ReadonlyArray<string>)
@@ -89,7 +89,7 @@ namespace ts {
             return createCombinedCodeActions(changes, commands.length === 0 ? undefined : commands);
         }
 
-        export function eachDiagnostic({ program, sourceFile, cancellationToken }: CodeFixAllContext, errorCodes: number[], cb: (diag: DiagnosticWithLocation) => void): void {
+        export function eachDiagnostic({ program, sourceFile, cancellationToken }: CodeFixAllContext, errorCodes: ReadonlyArray<number>, cb: (diag: DiagnosticWithLocation) => void): void {
             for (const diag of program.getSemanticDiagnostics(sourceFile, cancellationToken).concat(computeSuggestionDiagnostics(sourceFile, program, cancellationToken))) {
                 if (contains(errorCodes, diag.code)) {
                     cb(diag as DiagnosticWithLocation);