Add test for using export = with --allowSyntheticDefaultExports

Author: Andy Hanson

src/services/importTracker.ts

@@ -180,7 +180,8 @@ namespace ts.FindAllReferences {
      * But re-exports will be placed in 'singleReferences' since they cannot be locally referenced.
      */
     function getSearchesFromDirectImports(directImports: Importer[], exportSymbol: Symbol, exportKind: ExportKind, checker: TypeChecker, isForRename: boolean): Pick<ImportsResult, "importSearches" | "singleReferences"> {
-        const exportName = exportKind === ExportKind.Default ? "default" : exportSymbol.escapedName;
+        // Use name of "default" even in `export =` case because we may have allowSyntheticDefaultImports
+        const exportName = exportKind !== ExportKind.Named ? "default" : exportSymbol.escapedName;
         const importSearches: Array<[Identifier, Symbol]> = [];
         const singleReferences: Identifier[] = [];
         function addSearch(location: Identifier, symbol: Symbol): void {

tests/cases/fourslash/findAllRefsForDefaultExport_reExport_allowSyntheticDefaultImports.ts

@@ -0,0 +1,32 @@
+/// <reference path='fourslash.ts' />
+
+// @allowSyntheticDefaultImports: true
+
+// @Filename: /export.ts
+////const [|{| "isWriteAccess": true, "isDefinition": true |}foo|] = 1;
+////export = [|foo|];
+
+// @Filename: /re-export.ts
+////export { [|{| "isWriteAccess": true, "isDefinition": true |}default|] } from "./export";
+
+// @Filename: /re-export-dep.ts
+////import [|{| "isWriteAccess": true, "isDefinition": true |}fooDefault|] from "./re-export";
+
+verify.noErrors();
+
+const [r0, r1, r2, r3] = test.ranges();
+verify.referenceGroups([r0, r1], [
+    { definition: "const foo: 1", ranges: [r0, r1] },
+    { definition: "import default", ranges: [r2], },
+    { definition: "import fooDefault", ranges: [r3] },
+]);
+verify.referenceGroups(r2, [
+    { definition: "import default", ranges: [r2] },
+    { definition: "import fooDefault", ranges: [r3] },
+    { definition: "const foo: 1", ranges: [r0, r1] },
+]);
+verify.referenceGroups(r3, [
+    { definition: "import fooDefault", ranges: [r3] },
+    { definition: "import default", ranges: [r2] },
+    { definition: "const foo: 1", ranges: [r0, r1] },
+]);