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packager/src/Resolver/polyfills/__tests__/require-test.js

@@ -0,0 +1,135 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+// TODO: figure out why jest.resetModules() doesn't reset the polyfill's module cache
+const origGlobalRequire = global.require;
+require('../require');
+const requireShim = global.require;
+const defineShim = global.__d;
+global.require = origGlobalRequire;
+
+describe('require', () => {
+ describe('exports', () => {
+ it('should be an object containing named exports', () => {
+ defineShim(function(global, require, module, exports) {
+ expect(exports).toEqual({});
+ exports.hello = 'world';
+ },1);
+ expect(requireShim(1)).toEqual({hello: 'world'});
+ });
+ });
+
+ describe('this', () => {
+ it('should be the exports object', () => {
+ defineShim(function(global, require, module, exports) {
+ expect(this).toBe(exports);
+ },2);
+ requireShim(2);
+ });
+ });
+
+ describe('module.id', () => {
+ it('should be the identifier of the module passed to require', () => {
+ defineShim(function(global, require, module, exports) {
+ expect(module.id).toBe(3);
+ },3);
+ requireShim(3);
+ });
+ });
+
+ describe('module.exports', () => {
+ it('should be the same as exports', () => {
+ defineShim(function(global, require, module, exports) {
+ expect(module.exports).toBe(exports);
+ },11);
+ requireShim(11);
+ });
+
+ describe('should support re-assignements', () => {
+ let moduleId = 21;
+ function testModuleExportsValue(value) {
+ defineShim(function(global, require, module, exports) {
+ module.exports = value;
+ },moduleId);
+ expect(requireShim(moduleId)).toBe(value);
+ moduleId++;
+ }
+
+ it('to a primitive value', () => {
+ testModuleExportsValue(123);
+ });
+
+ it('to an object', () => {
+ testModuleExportsValue({
+ hello: 'world'
+ });
+ });
+
+ it('to a function', () => {
+ testModuleExportsValue(function Test() {});
+ });
+ });
+ });
+
+ describe('dependencies', () => {
+ it('should be resolved', () => {
+ defineShim(function(global, require, module, exports) {
+ exports.dep2 = require(32);
+ },31);
+ defineShim(function(global, require, module, exports) {
+ exports.hello = 'world';
+ },32);
+ expect(requireShim(31)).toEqual({
+ dep2: {
+ hello: 'world'
+ }
+ });
+ });
+
+ it('should handle circular deps using exports', () => {
+ defineShim(function(global, require, module, exports) {
+ exports.first = 'first value';
+ var p = require(42).p;
+ exports.first = 'second value';
+ exports.firstWas = p();
+ },41);
+ defineShim(function(global, require, module, exports) {
+ var first = require(41).first;
+ exports.p = function() {
+ return first;
+ }
+ },42);
+ expect(requireShim(41)).toEqual({
+ first: 'second value',
+ firstWas: 'first value'
+ });
+ });
+
+ it('should handle circular deps using module.exports', () => {
+ defineShim(function(global, require, module, exports) {
+ module.exports = {
+ first: 'first value'
+ };
+ var p = require(52).p;
+ module.exports.first = 'second value';
+ module.exports.firstWas = p();
+ },51);
+ defineShim(function(global, require, module, exports) {
+ var first = require(51).first;
+ exports.p = function() {
+ return first;
+ }
+ },52);
+ expect(requireShim(51)).toEqual({
+ first: 'second value',
+ firstWas: 'first value'
+ });
+ });
+ });
+});

packager/src/Resolver/polyfills/require.js

@@ -155,23 +155,33 @@ function loadModuleImplementation(moduleId, module) {
  // factory to keep any require cycles inside the factory from causing an
  // infinite require loop.
  module.isInitialized = true;
- const exports = module.exports = {};
+ module.exports = {};
  const {factory, dependencyMap} = module;
  try {
  if (__DEV__) {
  // $FlowFixMe: we know that __DEV__ is const and `Systrace` exists
  Systrace.beginEvent('JS_require_' + (module.verboseName || moduleId));
  }
 
- const moduleObject: Module = {exports};
+ const moduleObject = {
+ get id() {
+ return moduleId;
+ },
+ get exports() {
+ return module.exports;
+ },
+ set exports(value) {
+ module.exports = value;
+ }
+ };
  if (__DEV__ && module.hot) {
  moduleObject.hot = module.hot;
  }
 
  // keep args in sync with with defineModuleCode in
  // packager/src//Resolver/index.js
  // and packager/src//ModuleGraph/worker.js
- factory(global, require, moduleObject, exports, dependencyMap);
+ factory.call(module.exports, global, require, moduleObject, module.exports, dependencyMap);
 
  // avoid removing factory in DEV mode as it breaks HMR
  if (!__DEV__) {
@@ -183,7 +193,7 @@ function loadModuleImplementation(moduleId, module) {
  // $FlowFixMe: we know that __DEV__ is const and `Systrace` exists
  Systrace.endEvent();
  }
- return (module.exports = moduleObject.exports);
+ return module.exports;
  } catch (e) {
  module.hasError = true;
  module.error = e;