fix(58772): Duplicate exports.* = assignments in CommonJS output in some cases (microsoft#59120)

a-tarasyuk · web-flow · commit 8a0e47e24211 · 2024-07-22T16:10:29.000-07:00
diff --git a/src/compiler/transformers/utilities.ts b/src/compiler/transformers/utilities.ts
@@ -47,6 +47,7 @@ import {
     isClassStaticBlockDeclaration,
     isDefaultImport,
     isExpressionStatement,
+    isFunctionDeclaration,
     isGeneratedIdentifier,
     isGeneratedPrivateIdentifier,
     isIdentifier,
@@ -321,7 +322,7 @@ export function collectExternalModuleInfo(context: TransformationContext, source
     }
 
     function addExportedFunctionDeclaration(node: FunctionDeclaration, name: ModuleExportName | undefined, isDefault: boolean) {
-        exportedFunctions.add(node);
+        exportedFunctions.add(getOriginalNode(node, isFunctionDeclaration));
         if (isDefault) {
             // export default function() { }
             // function x() { } + export { x as default };
diff --git a/tests/baselines/reference/exportsAndImports5.js b/tests/baselines/reference/exportsAndImports5.js
@@ -0,0 +1,24 @@
+//// [tests/cases/conformance/es6/modules/exportsAndImports5.ts] ////
+
+//// [a.ts]
+export interface A { }
+
+//// [b.ts]
+import { A } from "./a"
+export function f(): A {
+    return {};
+}
+export { f as fV2 };
+
+
+//// [a.js]
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+//// [b.js]
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.f = f;
+exports.fV2 = f;
+function f() {
+    return {};
+}
diff --git a/tests/baselines/reference/exportsAndImports5.symbols b/tests/baselines/reference/exportsAndImports5.symbols
@@ -0,0 +1,20 @@
+//// [tests/cases/conformance/es6/modules/exportsAndImports5.ts] ////
+
+=== a.ts ===
+export interface A { }
+>A : Symbol(A, Decl(a.ts, 0, 0))
+
+=== b.ts ===
+import { A } from "./a"
+>A : Symbol(A, Decl(b.ts, 0, 8))
+
+export function f(): A {
+>f : Symbol(f, Decl(b.ts, 0, 23))
+>A : Symbol(A, Decl(b.ts, 0, 8))
+
+    return {};
+}
+export { f as fV2 };
+>f : Symbol(f, Decl(b.ts, 0, 23))
+>fV2 : Symbol(fV2, Decl(b.ts, 4, 8))
+
diff --git a/tests/baselines/reference/exportsAndImports5.types b/tests/baselines/reference/exportsAndImports5.types
@@ -0,0 +1,25 @@
+//// [tests/cases/conformance/es6/modules/exportsAndImports5.ts] ////
+
+=== a.ts ===
+
+export interface A { }
+
+=== b.ts ===
+import { A } from "./a"
+>A : any
+>  : ^^^
+
+export function f(): A {
+>f : () => A
+>  : ^^^^^^ 
+
+    return {};
+>{} : {}
+>   : ^^
+}
+export { f as fV2 };
+>f : () => A
+>  : ^^^^^^ 
+>fV2 : () => A
+>    : ^^^^^^ 
+
diff --git a/tests/cases/conformance/es6/modules/exportsAndImports5.ts b/tests/cases/conformance/es6/modules/exportsAndImports5.ts
@@ -0,0 +1,11 @@
+// @module: commonjs
+
+// @filename: a.ts
+export interface A { }
+
+// @filename: b.ts
+import { A } from "./a"
+export function f(): A {
+    return {};
+}
+export { f as fV2 };
