Improve output for re-exporting

packages/babel-helper-module-transforms/src/normalize-and-load-metadata.ts

@@ -6,9 +6,11 @@ import splitExportDeclaration from "@babel/helper-split-export-declaration";
 import type { NodePath } from "@babel/traverse";
 
 export interface ModuleMetadata {
+ // `undefined` means legacy behavior, `boolean` means emit `exports.x = y` for `cjs-module-lexer` compat.
+ implicitAssignmentExports: boolean | undefined;
+ programPath: NodePath<t.Program>;
  exportName: string;
- // The name of the variable that will reference an object containing export names.
- exportNameListName: null | string;
+ exportNameList?: string[];
  hasExports: boolean;
  // Lookup from local binding to export information.
  local: Map<string, LocalExportMetadata>;
@@ -179,8 +181,9 @@ export default function normalizeModuleAndLoadMetadata(
  }
 
  return {
+ implicitAssignmentExports: undefined,
+ programPath,
  exportName,
- exportNameListName: null,
  hasExports,
  local,
  source: sources,

packages/babel-helpers/src/helpers-generated.ts

@@ -123,10 +123,10 @@ export default Object.freeze({
  "7.23.0",
  "export default function _importDeferProxy(e){var t=null,constValue=function(e){return function(){return e}},proxy=function(r){return function(n,o,f){return null===t&&(t=e()),r(t,o,f)}};return new Proxy({},{defineProperty:constValue(!1),deleteProperty:constValue(!1),get:proxy(Reflect.get),getOwnPropertyDescriptor:proxy(Reflect.getOwnPropertyDescriptor),getPrototypeOf:constValue(null),isExtensible:constValue(!1),has:proxy(Reflect.has),ownKeys:proxy(Reflect.ownKeys),preventExtensions:constValue(!0),set:constValue(!1),setPrototypeOf:constValue(!1)})}",
  ),
- // size: 693, gzip size: 361
+ // size: 505, gzip size: 314
  interopRequireWildcard: helper(
  "7.14.0",
- 'function _getRequireWildcardCache(e){if("function"!=typeof WeakMap)return null;var r=new WeakMap,t=new WeakMap;return(_getRequireWildcardCache=function(e){return e?t:r})(e)}export default function _interopRequireWildcard(e,r){if(!r&&e&&e.__esModule)return e;if(null===e||"object"!=typeof e&&"function"!=typeof e)return{default:e};var t=_getRequireWildcardCache(r);if(t&&t.has(e))return t.get(e);var n={__proto__:null},a=Object.defineProperty&&Object.getOwnPropertyDescriptor;for(var u in e)if("default"!==u&&Object.prototype.hasOwnProperty.call(e,u)){var i=a?Object.getOwnPropertyDescriptor(e,u):null;i&&(i.get||i.set)?Object.defineProperty(n,u,i):n[u]=e[u]}return n.default=e,t&&t.set(e,n),n}',
+ 'export default function _interopRequireWildcard(e,t){if("function"==typeof WeakMap)var r=new WeakMap,n=new WeakMap;return(_interopRequireWildcard=function(e,t){if(!t&&e&&e.__esModule)return e;var a,i=t?n:r,o={__proto__:null,default:e};if(null==e||Object(e)!==e)return o;if(i){if(i.has(e))return i.get(e);i.set(e,o)}for(const t in e)"default"!==t&&{}.hasOwnProperty.call(e,t)&&((a=Object.create&&Object.getOwnPropertyDescriptor(e,t))&&(a.get||a.set)?Object.defineProperty(o,t,a):o[t]=e[t]);return o})(e,t)}',
  ),
  // size: 208, gzip size: 154
  isNativeReflectConstruct: helper(

packages/babel-helpers/src/helpers/interopRequireWildcard.ts

@@ -0,0 +1,46 @@
+/* @minVersion 7.14.0 */
+
+export default function _interopRequireWildcard(
+ obj: any,
+ nodeInterop: boolean,
+) {
+ if (typeof WeakMap === "function") {
+ var cacheBabelInterop = new WeakMap();
+ var cacheNodeInterop = new WeakMap();
+ }
+
+ // @ts-expect-error: assign to function
+ return (_interopRequireWildcard = function (obj: any, nodeInterop: boolean) {
+ // eslint-disable-next-line @typescript-eslint/prefer-optional-chain
+ if (!nodeInterop && obj && obj.__esModule) {
+ return obj;
+ }
+
+ var cache = nodeInterop ? cacheNodeInterop : cacheBabelInterop,
+ newObj: any = { __proto__: null, default: obj },
+ desc: PropertyDescriptor;
+
+ if (obj == null || Object(obj) !== obj) {
+ return newObj;
+ }
+
+ if (cache) {
+ if (cache.has(obj)) return cache.get(obj);
+ cache.set(obj, newObj);
+ }
+
+ for (const key in obj) {
+ if (key !== "default" && {}.hasOwnProperty.call(obj, key)) {
+ // Object.create and Object.defineProperty and Object.getOwnPropertyDescriptor
+ // must all be defined or undefined together.
+ desc = Object.create && Object.getOwnPropertyDescriptor(obj, key);
+ if (desc && (desc.get || desc.set)) {
+ Object.defineProperty(newObj, key, desc);
+ } else {
+ newObj[key] = obj[key];
+ }
+ }
+ }
+ return newObj;
+ })(obj, nodeInterop);
+}

packages/babel-plugin-transform-modules-amd/src/index.ts

@@ -154,6 +154,7 @@ export default declare<State>((api, options: Options) => {
  const { meta, headers } = rewriteModuleStatementsAndPrepareHeader(
  path,
  {
+ implicitAssignmentExports: true,
  enumerableModuleMeta,
  constantReexports,
  strict,

packages/babel-plugin-transform-modules-amd/test/fixtures/amd/export-from-2/output.js

@@ -4,10 +4,13 @@ define(["exports", "foo"], function (_exports, _foo) {
  Object.defineProperty(_exports, "__esModule", {
  value: true
  });
- Object.defineProperty(_exports, "foo", {
- enumerable: true,
- get: function () {
- return _foo.foo;
- }
- });
+ _export("foo", _foo);
+ function _export(name, mod, name2) {
+ Object.defineProperty(_exports, name, {
+ enumerable: true,
+ get: function () {
+ return mod[name2 == null ? name : name2];
+ }
+ });
+ }
 });

packages/babel-plugin-transform-modules-amd/test/fixtures/amd/export-from-3/output.js

@@ -4,16 +4,14 @@ define(["exports", "foo"], function (_exports, _foo) {
  Object.defineProperty(_exports, "__esModule", {
  value: true
  });
- Object.defineProperty(_exports, "bar", {
- enumerable: true,
- get: function () {
- return _foo.bar;
- }
- });
- Object.defineProperty(_exports, "foo", {
- enumerable: true,
- get: function () {
- return _foo.foo;
- }
- });
+ _export("bar", _foo);
+ _export("foo", _foo);
+ function _export(name, mod, name2) {
+ Object.defineProperty(_exports, name, {
+ enumerable: true,
+ get: function () {
+ return mod[name2 == null ? name : name2];
+ }
+ });
+ }
 });

packages/babel-plugin-transform-modules-amd/test/fixtures/amd/export-from-4/output.js

@@ -4,10 +4,13 @@ define(["exports", "foo"], function (_exports, _foo) {
  Object.defineProperty(_exports, "__esModule", {
  value: true
  });
- Object.defineProperty(_exports, "bar", {
- enumerable: true,
- get: function () {
- return _foo.foo;
- }
- });
+ _export("bar", _foo, "foo");
+ function _export(name, mod, name2) {
+ Object.defineProperty(_exports, name, {
+ enumerable: true,
+ get: function () {
+ return mod[name2 == null ? name : name2];
+ }
+ });
+ }
 });

packages/babel-plugin-transform-modules-amd/test/fixtures/amd/export-from-5/output.js

@@ -4,10 +4,13 @@ define(["exports", "foo"], function (_exports, _foo) {
  Object.defineProperty(_exports, "__esModule", {
  value: true
  });
- Object.defineProperty(_exports, "default", {
- enumerable: true,
- get: function () {
- return _foo.foo;
- }
- });
+ _export("default", _foo, "foo");
+ function _export(name, mod, name2) {
+ Object.defineProperty(_exports, name, {
+ enumerable: true,
+ get: function () {
+ return mod[name2 == null ? name : name2];
+ }
+ });
+ }
 });

packages/babel-plugin-transform-modules-amd/test/fixtures/amd/export-from-6/output.js

@@ -4,16 +4,14 @@ define(["exports", "foo"], function (_exports, _foo) {
  Object.defineProperty(_exports, "__esModule", {
  value: true
  });
- Object.defineProperty(_exports, "bar", {
- enumerable: true,
- get: function () {
- return _foo.bar;
- }
- });
- Object.defineProperty(_exports, "default", {
- enumerable: true,
- get: function () {
- return _foo.foo;
- }
- });
+ _export("bar", _foo);
+ _export("default", _foo, "foo");
+ function _export(name, mod, name2) {
+ Object.defineProperty(_exports, name, {
+ enumerable: true,
+ get: function () {
+ return mod[name2 == null ? name : name2];
+ }
+ });
+ }
 });

packages/babel-plugin-transform-modules-amd/test/fixtures/amd/export-from/output.js

@@ -4,14 +4,18 @@ define(["exports", "foo"], function (_exports, _foo) {
  Object.defineProperty(_exports, "__esModule", {
  value: true
  });
- Object.keys(_foo).forEach(function (key) {
- if (key === "default" || key === "__esModule") return;
- if (key in _exports && _exports[key] === _foo[key]) return;
- Object.defineProperty(_exports, key, {
- enumerable: true,
- get: function () {
- return _foo[key];
+ _exportStar(_foo);
+ function _exportStar(mod) {
+ Object.keys(mod).forEach(function (k) {
+ if (["default", "__esModule"].indexOf(k) < 0 && !(k in _exports && _exports[k] === mod[k])) {
+ Object.defineProperty(_exports, k, {
+ get: function () {
+ return mod[k];
+ },
+ enumerable: true
+ });
  }
  });
- });
+ return mod;
+ }
 });

packages/babel-plugin-transform-modules-amd/test/fixtures/amd/noInterop-export-from/output.js

@@ -4,10 +4,13 @@ define(["exports", "foo"], function (_exports, _foo) {
  Object.defineProperty(_exports, "__esModule", {
  value: true
  });
- Object.defineProperty(_exports, "default", {
- enumerable: true,
- get: function () {
- return _foo.default;
- }
- });
+ _export("default", _foo);
+ function _export(name, mod, name2) {
+ Object.defineProperty(_exports, name, {
+ enumerable: true,
+ get: function () {
+ return mod[name2 == null ? name : name2];
+ }
+ });
+ }
 });

packages/babel-plugin-transform-modules-amd/test/fixtures/assumption-constantReexports/export-from-6/output.js

@@ -4,9 +4,13 @@ define(["exports", "foo"], function (_exports, _foo) {
  Object.defineProperty(_exports, "__esModule", {
  value: true
  });
- Object.keys(_foo).forEach(function (key) {
- if (key === "default" || key === "__esModule") return;
- if (key in _exports && _exports[key] === _foo[key]) return;
- _exports[key] = _foo[key];
- });
+ _exportStar(_foo);
+ function _exportStar(mod) {
+ Object.keys(mod).forEach(function (k) {
+ if (["default", "__esModule"].indexOf(k) < 0 && !(k in _exports && _exports[k] === mod[k])) {
+ _exports[k] = mod[k];
+ }
+ });
+ return mod;
+ }
 });

packages/babel-plugin-transform-modules-amd/test/fixtures/importInterop-node/export-named-and-default-from/output.js

@@ -4,17 +4,15 @@ define(["exports", "dep"], function (_exports, _dep) {
  Object.defineProperty(_exports, "__esModule", {
  value: true
  });
- Object.defineProperty(_exports, "default", {
- enumerable: true,
- get: function () {
- return _dep.default;
- }
- });
- Object.defineProperty(_exports, "name", {
- enumerable: true,
- get: function () {
- return _dep.name;
- }
- });
+ _export("default", _dep);
+ _export("name", _dep);
  _dep = babelHelpers.interopRequireWildcard(_dep, true);
+ function _export(name, mod, name2) {
+ Object.defineProperty(_exports, name, {
+ enumerable: true,
+ get: function () {
+ return mod[name2 == null ? name : name2];
+ }
+ });
+ }
 });

packages/babel-plugin-transform-modules-amd/test/fixtures/importInterop-node/export-named-from/output.js

@@ -4,10 +4,13 @@ define(["exports", "dep"], function (_exports, _dep) {
  Object.defineProperty(_exports, "__esModule", {
  value: true
  });
- Object.defineProperty(_exports, "name", {
- enumerable: true,
- get: function () {
- return _dep.name;
- }
- });
+ _export("name", _dep);
+ function _export(name, mod, name2) {
+ Object.defineProperty(_exports, name, {
+ enumerable: true,
+ get: function () {
+ return mod[name2 == null ? name : name2];
+ }
+ });
+ }
 });

packages/babel-plugin-transform-modules-amd/test/fixtures/importInterop-none/export-from/output.js

@@ -4,10 +4,13 @@ define(["exports", "foo"], function (_exports, _foo) {
  Object.defineProperty(_exports, "__esModule", {
  value: true
  });
- Object.defineProperty(_exports, "default", {
- enumerable: true,
- get: function () {
- return _foo.default;
- }
- });
+ _export("default", _foo);
+ function _export(name, mod, name2) {
+ Object.defineProperty(_exports, name, {
+ enumerable: true,
+ get: function () {
+ return mod[name2 == null ? name : name2];
+ }
+ });
+ }
 });