findAllReferences: In export default foo, symbol name is foo

tests/cases/fourslash/findAllRefsForDefaultExport04.ts

@@ -0,0 +1,16 @@
+/// <reference path='fourslash.ts' />
+
+// @Filename: /a.ts
+////const [|{| "isWriteAccess": true, "isDefinition": true |}a|] = 0;
+////export default [|a|];
+
+// @Filename: /b.ts
+////import [|{| "isWriteAccess": true, "isDefinition": true |}a|] from "./a";
+////[|a|];
+
+const [r0, r1, r2, r3] = test.ranges();
+verify.referenceGroups([r0, r1], [
+    { definition: "const a: 0", ranges: [r0, r1] },
+    { definition: "import a", ranges: [r2, r3] }
+]);
+verify.singleReferenceGroup("import a", [r2, r3]);