Make import fix for 'export =' respect module target and allowSyntheticDefaultImports/esModuleInterop

src/harness/fourslash.ts

@@ -2328,7 +2328,10 @@ Actual: ${stringify(fullActual)}`);
         public applyCodeActionFromCompletion(markerName: string, options: FourSlashInterface.VerifyCompletionActionOptions) {
             this.goToMarker(markerName);
 
-            const details = this.getCompletionEntryDetails(options.name, options.source, options.preferences)!;
+            const details = this.getCompletionEntryDetails(options.name, options.source, options.preferences);
+            if (!details) {
+                return this.raiseError(`No completions were found for the given name, source, and preferences.`);
+            }
             const codeActions = details.codeActions!;
             if (codeActions.length !== 1) {
                 this.raiseError(`Expected one code action, got ${codeActions.length}`);

src/services/codefixes/importFixes.ts

@@ -163,7 +163,7 @@ namespace ts.codefix {
         position: number,
         preferences: UserPreferences,
     ): { readonly moduleSpecifier: string, readonly codeAction: CodeAction } {
-        const exportInfos = getAllReExportingModules(exportedSymbol, moduleSymbol, symbolName, sourceFile, program.getCompilerOptions(), program.getTypeChecker(), program.getSourceFiles());
+        const exportInfos = getAllReExportingModules(sourceFile, exportedSymbol, moduleSymbol, symbolName, sourceFile, program.getCompilerOptions(), program.getTypeChecker(), program.getSourceFiles());
         Debug.assert(exportInfos.some(info => info.moduleSymbol === moduleSymbol));
         // We sort the best codefixes first, so taking `first` is best for completions.
         const moduleSpecifier = first(getNewImportInfos(program, sourceFile, position, exportInfos, host, preferences)).moduleSpecifier;
@@ -175,15 +175,15 @@ namespace ts.codefix {
         return { description, changes, commands };
     }
 
-    function getAllReExportingModules(exportedSymbol: Symbol, exportingModuleSymbol: Symbol, symbolName: string, sourceFile: SourceFile, compilerOptions: CompilerOptions, checker: TypeChecker, allSourceFiles: ReadonlyArray<SourceFile>): ReadonlyArray<SymbolExportInfo> {
+    function getAllReExportingModules(importingFile: SourceFile, exportedSymbol: Symbol, exportingModuleSymbol: Symbol, symbolName: string, sourceFile: SourceFile, compilerOptions: CompilerOptions, checker: TypeChecker, allSourceFiles: ReadonlyArray<SourceFile>): ReadonlyArray<SymbolExportInfo> {
         const result: SymbolExportInfo[] = [];
         forEachExternalModule(checker, allSourceFiles, (moduleSymbol, moduleFile) => {
             // Don't import from a re-export when looking "up" like to `./index` or `../index`.
             if (moduleFile && moduleSymbol !== exportingModuleSymbol && startsWith(sourceFile.fileName, getDirectoryPath(moduleFile.fileName))) {
                 return;
             }
 
-            const defaultInfo = getDefaultLikeExportInfo(moduleSymbol, checker, compilerOptions);
+            const defaultInfo = getDefaultLikeExportInfo(importingFile, moduleSymbol, checker, compilerOptions);
             if (defaultInfo && defaultInfo.name === symbolName && skipAlias(defaultInfo.symbol, checker) === exportedSymbol) {
                 result.push({ moduleSymbol, importKind: defaultInfo.kind, exportedSymbolIsTypeOnly: isTypeOnlySymbol(defaultInfo.symbol, checker) });
             }
@@ -329,7 +329,7 @@ namespace ts.codefix {
         if (!umdSymbol) return undefined;
         const symbol = checker.getAliasedSymbol(umdSymbol);
         const symbolName = umdSymbol.name;
-        const exportInfos: ReadonlyArray<SymbolExportInfo> = [{ moduleSymbol: symbol, importKind: getUmdImportKind(program.getCompilerOptions()), exportedSymbolIsTypeOnly: false }];
+        const exportInfos: ReadonlyArray<SymbolExportInfo> = [{ moduleSymbol: symbol, importKind: getUmdImportKind(sourceFile, program.getCompilerOptions()), exportedSymbolIsTypeOnly: false }];
         const fixes = getFixForImport(exportInfos, symbolName, isIdentifier(token) ? token.getStart(sourceFile) : undefined, program, sourceFile, host, preferences);
         return { fixes, symbolName };
     }
@@ -345,7 +345,7 @@ namespace ts.codefix {
             : undefined;
     }
 
-    function getUmdImportKind(compilerOptions: CompilerOptions): ImportKind {
+    function getUmdImportKind(importingFile: SourceFile, compilerOptions: CompilerOptions): ImportKind {
         // Import a synthetic `default` if enabled.
         if (getAllowSyntheticDefaultImports(compilerOptions)) {
             return ImportKind.Default;
@@ -357,7 +357,7 @@ namespace ts.codefix {
             case ModuleKind.AMD:
             case ModuleKind.CommonJS:
             case ModuleKind.UMD:
-                return ImportKind.Equals;
+                return isInJSFile(importingFile) ? ImportKind.Default : ImportKind.Equals;
             case ModuleKind.System:
             case ModuleKind.ES2015:
             case ModuleKind.ESNext:
@@ -403,7 +403,7 @@ namespace ts.codefix {
         forEachExternalModuleToImportFrom(checker, sourceFile, program.getSourceFiles(), moduleSymbol => {
             cancellationToken.throwIfCancellationRequested();
 
-            const defaultInfo = getDefaultLikeExportInfo(moduleSymbol, checker, program.getCompilerOptions());
+            const defaultInfo = getDefaultLikeExportInfo(sourceFile, moduleSymbol, checker, program.getCompilerOptions());
             if (defaultInfo && defaultInfo.name === symbolName && symbolHasMeaning(defaultInfo.symbolForMeaning, currentTokenMeaning)) {
                 addSymbol(moduleSymbol, defaultInfo.symbol, defaultInfo.kind);
             }
@@ -418,20 +418,26 @@ namespace ts.codefix {
     }
 
     function getDefaultLikeExportInfo(
-        moduleSymbol: Symbol, checker: TypeChecker, compilerOptions: CompilerOptions,
-    ): { readonly symbol: Symbol, readonly symbolForMeaning: Symbol, readonly name: string, readonly kind: ImportKind.Default | ImportKind.Equals } | undefined {
-        const exported = getDefaultLikeExportWorker(moduleSymbol, checker);
+        importingFile: SourceFile, moduleSymbol: Symbol, checker: TypeChecker, compilerOptions: CompilerOptions,
+    ): { readonly symbol: Symbol, readonly symbolForMeaning: Symbol, readonly name: string, readonly kind: ImportKind } | undefined {
+        const exported = getDefaultLikeExportWorker(importingFile, moduleSymbol, checker, compilerOptions);
         if (!exported) return undefined;
         const { symbol, kind } = exported;
         const info = getDefaultExportInfoWorker(symbol, moduleSymbol, checker, compilerOptions);
         return info && { symbol, kind, ...info };
     }
 
-    function getDefaultLikeExportWorker(moduleSymbol: Symbol, checker: TypeChecker): { readonly symbol: Symbol, readonly kind: ImportKind.Default | ImportKind.Equals } | undefined {
+    function getDefaultLikeExportWorker(importingFile: SourceFile, moduleSymbol: Symbol, checker: TypeChecker, compilerOptions: CompilerOptions): { readonly symbol: Symbol, readonly kind: ImportKind } | undefined {
         const defaultExport = checker.tryGetMemberInModuleExports(InternalSymbolName.Default, moduleSymbol);
         if (defaultExport) return { symbol: defaultExport, kind: ImportKind.Default };
         const exportEquals = checker.resolveExternalModuleSymbol(moduleSymbol);
-        return exportEquals === moduleSymbol ? undefined : { symbol: exportEquals, kind: ImportKind.Equals };
+        return exportEquals === moduleSymbol ? undefined : { symbol: exportEquals, kind: getImportKindForExportEquals(importingFile, compilerOptions) };
+    }
+
+    function getImportKindForExportEquals(importingFile: SourceFile, compilerOptions: CompilerOptions): ImportKind {
+        return (isInJSFile(importingFile) || getAllowSyntheticDefaultImports(compilerOptions) && getEmitModuleKind(compilerOptions) >= ModuleKind.ES2015)
+            ? ImportKind.Default
+            : ImportKind.Equals;
     }
 
     function getDefaultExportInfoWorker(defaultExport: Symbol, moduleSymbol: Symbol, checker: TypeChecker, compilerOptions: CompilerOptions): { readonly symbolForMeaning: Symbol, readonly name: string } | undefined {

tests/cases/fourslash/importNameCodeFixNewImportExportEqualsESModuleInterop.ts

@@ -0,0 +1,20 @@
+/// <reference path="fourslash.ts" />
+
+// @EsModuleInterop: true
+// @Module: es2015
+
+// @Filename: /foo.d.ts
+////declare module "foo" {
+////  const _default: number;
+////  export = _default;
+////}
+
+// @Filename: /index.ts
+////foo/**/
+
+goTo.marker('');
+verify.getAndApplyCodeFix(2304, 0);
+verify.currentFileContentIs(
+`import foo from "foo";
+
+foo`);

tests/cases/fourslash/importNameCodeFixNewImportExportEqualsESNext.ts

@@ -0,0 +1,19 @@
+/// <reference path="fourslash.ts" />
+
+// @Module: esnext
+
+// @Filename: /foo.d.ts
+////declare module "foo" {
+////  const _default: number;
+////  export = _default;
+////}
+
+// @Filename: /index.ts
+////foo/**/
+
+goTo.marker('');
+verify.getAndApplyCodeFix(2304, 0);
+verify.currentFileContentIs(
+`import foo = require("foo");
+
+foo`);

tests/cases/fourslash/importNameCodeFixNewImportExportEqualsJavaScript.ts

@@ -0,0 +1,20 @@
+/// <reference path="fourslash.ts" />
+
+// @allowJs: true
+// @checkJs: true
+
+// @Filename: /foo.d.ts
+////declare module "foo" {
+////  const _default: number;
+////  export = _default;
+////}
+
+// @Filename: /index.js
+////foo/**/
+
+goTo.marker('');
+verify.getAndApplyCodeFix(2304, 0);
+verify.currentFileContentIs(
+`import foo from "foo";
+
+foo`);

tests/cases/fourslash/importNameCodeFixUMDGlobalJavaScript.ts

@@ -0,0 +1,21 @@
+/// <reference path="fourslash.ts" />
+
+// @AllowSyntheticDefaultImports: false
+// @Module: commonjs
+// @CheckJs: true
+// @AllowJs: true
+
+// @Filename: a/f1.js
+//// [|export function test() { };
+//// bar1/*0*/.bar;|]
+
+// @Filename: a/foo.d.ts
+//// export declare function bar(): number;
+//// export as namespace bar1; 
+
+verify.importFixAtPosition([
+`import bar1 from "./foo";
+
+export function test() { };
+bar1.bar;`
+]);