feat: add createMockFromModule to replace genMockFromModule (#9962)

Author: SimenB

CHANGELOG.md

@@ -4,6 +4,7 @@
 
 - `[jest-environment-jsdom]` [**BREAKING**] Upgrade `jsdom` to v16 ([#9606](https://github.com/facebook/jest/pull/9606))
 - `[@jest/fake-timers]` Add possibility to use a modern implementation of fake timers, backed by `@sinonjs/fake-timers` ([#7776](https://github.com/facebook/jest/pull/7776))
+- `[jest-runtime]` Add `createMockFromModule` as an alias for `genMockFromModule` ([#9962](https://github.com/facebook/jest/pull/9962))
 
 ### Fixes
 

docs/JestObjectAPI.md

@@ -90,7 +90,11 @@ test('original implementation', () => {
 
 _Note: this method was previously called `autoMockOn`. When using `babel-jest`, calls to `enableAutomock` will automatically be hoisted to the top of the code block. Use `autoMockOn` if you want to explicitly avoid this behavior._
 
-### `jest.genMockFromModule(moduleName)`
+### `jest.createMockFromModule(moduleName)`
+
+##### renamed in Jest **26.0.0+**
+
+Also under the alias: `.genMockFromModule(moduleName)`
 
 Given the name of a module, use the automatic mocking system to generate a mocked version of the module for you.
 
@@ -109,17 +113,17 @@ export default {
 ```
 
 ```js
-// __tests__/genMockFromModule.test.js
-const utils = jest.genMockFromModule('../utils').default;
+// __tests__/createMockFromModule.test.js
+const utils = jest.createMockFromModule('../utils').default;
 utils.isAuthorized = jest.fn(secret => secret === 'not wizard');
 
-test('implementation created by jest.genMockFromModule', () => {
+test('implementation created by jest.createMockFromModule', () => {
   expect(utils.authorize.mock).toBeTruthy();
   expect(utils.isAuthorized('not wizard')).toEqual(true);
 });
 ```
 
-This is how `genMockFromModule` will mock the following data types:
+This is how `createMockFromModule` will mock the following data types:
 
 #### `Function`
 
@@ -176,7 +180,7 @@ module.exports = {
 
 ```js
 // __tests__/example.test.js
-const example = jest.genMockFromModule('./example');
+const example = jest.createMockFromModule('./example');
 
 test('should run example code', () => {
   // creates a new mocked function with no formal arguments.

docs/ManualMocks.md

@@ -64,7 +64,7 @@ Since we'd like our tests to avoid actually hitting the disk (that's pretty slow
 
 const path = require('path');
 
-const fs = jest.genMockFromModule('fs');
+const fs = jest.createMockFromModule('fs');
 
 // This is a custom function that our tests can use during setup to specify
 // what the files on the "mock" filesystem should look like when any of the
@@ -124,7 +124,7 @@ describe('listFilesInDirectorySync', () => {
 });
 ```
 
-The example mock shown here uses [`jest.genMockFromModule`](JestObjectAPI.md#jestgenmockfrommodulemodulename) to generate an automatic mock, and overrides its default behavior. This is the recommended approach, but is completely optional. If you do not want to use the automatic mock at all, you can export your own functions from the mock file. One downside to fully manual mocks is that they're manual – meaning you have to manually update them any time the module they are mocking changes. Because of this, it's best to use or extend the automatic mock when it works for your needs.
+The example mock shown here uses [`jest.createMockFromModule`](JestObjectAPI.md#jestcreatemockfrommodulemodulename) to generate an automatic mock, and overrides its default behavior. This is the recommended approach, but is completely optional. If you do not want to use the automatic mock at all, you can export your own functions from the mock file. One downside to fully manual mocks is that they're manual – meaning you have to manually update them any time the module they are mocking changes. Because of this, it's best to use or extend the automatic mock when it works for your needs.
 
 To ensure that a manual mock and its real implementation stay in sync, it might be useful to require the real module using [`jest.requireActual(moduleName)`](JestObjectAPI.md#jestrequireactualmodulename) in your manual mock and amending it with mock functions before exporting it.
 

e2e/runtime-internal-module-registry/__mocks__/fs.js

@@ -7,7 +7,7 @@
 
 'use strict';
 
-const fs = jest.genMockFromModule('fs');
+const fs = jest.createMockFromModule('fs');
 
 let mkdirWasCalled = false;
 

examples/automatic-mocks/__tests__/genMockFromModule.test.js renamed to examples/automatic-mocks/__tests__/createMockFromModule.test.js

@@ -7,8 +7,8 @@ test('implementation created by automock', () => {
   expect(utils.isAuthorized()).toBeUndefined();
 });
 
-test('implementation created by jest.genMockFromModule', () => {
-  const utils = jest.genMockFromModule('../utils').default;
+test('implementation created by jest.createMockFromModule', () => {
+  const utils = jest.createMockFromModule('../utils').default;
   utils.isAuthorized = jest.fn(secret => secret === 'not wizard');
 
   expect(utils.authorize.mock).toBeTruthy();

examples/manual-mocks/__mocks__/fs.js

@@ -4,7 +4,7 @@
 
 const path = require('path');
 
-const fs = jest.genMockFromModule('fs');
+const fs = jest.createMockFromModule('fs');
 
 // This is a custom function that our tests can use during setup to specify
 // what the files on the "mock" filesystem should look like when any of the

examples/manual-mocks/__mocks__/lodash.js

@@ -1,6 +1,6 @@
 // Copyright 2004-present Facebook. All Rights Reserved.
 
-const lodash = jest.genMockFromModule('lodash');
+const lodash = jest.createMockFromModule('lodash');
 
 lodash.head = arr => 5;
 

examples/manual-mocks/models/__mocks__/user.js

@@ -1,6 +1,6 @@
 // Copyright 2004-present Facebook. All Rights Reserved.
 
-const user = jest.genMockFromModule('../user');
+const user = jest.createMockFromModule('../user');
 
 user.getAuthenticated = () => ({
   age: 622,

examples/module-mock/__tests__/partial_mock.js

@@ -9,7 +9,7 @@ import defaultExport, {apple, strawberry} from '../fruit';
 
 jest.mock('../fruit', () => {
   const originalModule = jest.requireActual('../fruit');
-  const mockedModule = jest.genMockFromModule('../fruit');
+  const mockedModule = jest.createMockFromModule('../fruit');
 
   //Mock the default export and named export 'apple'.
   return {

packages/jest-config/src/__mocks__/fs.js

@@ -7,7 +7,7 @@
 
 'use strict';
 
-const fs = jest.genMockFromModule('fs');
+const fs = jest.createMockFromModule('fs');
 
 const mockFiles = new Map();
 function __setMockFiles(newMockFiles) {

packages/jest-config/src/__mocks__/os.js

@@ -7,7 +7,7 @@
 
 'use strict';
 
-const os = jest.genMockFromModule('os');
+const os = jest.createMockFromModule('os');
 
 let cpus;
 function __setCpus(newCpus) {

packages/jest-environment-jsdom/src/__mocks__/index.ts

@@ -8,7 +8,7 @@
 
 const vm = jest.requireActual('vm');
 
-const JSDOMEnvironment = jest.genMockFromModule('../index') as jest.Mock;
+const JSDOMEnvironment = jest.createMockFromModule('../index') as jest.Mock;
 
 JSDOMEnvironment.mockImplementation(function (config) {
   // @ts-ignore

packages/jest-environment/src/index.ts

@@ -126,8 +126,18 @@ export interface Jest {
    *
    * This is useful when you want to create a manual mock that extends the
    * automatic mock's behavior.
+   *
+   * @deprecated Use `jest.createMockFromModule()` instead
    */
   genMockFromModule(moduleName: string): unknown;
+  /**
+   * Given the name of a module, use the automatic mocking system to generate a
+   * mocked version of the module for you.
+   *
+   * This is useful when you want to create a manual mock that extends the
+   * automatic mock's behavior.
+   */
+  createMockFromModule(moduleName: string): unknown;
   /**
    * Determines if the given function is a mocked function.
    */

packages/jest-haste-map/src/__tests__/worker.test.js

@@ -38,7 +38,7 @@ jest.mock('graceful-fs', () => {
   };
 
   return {
-    ...jest.genMockFromModule('graceful-fs'),
+    ...jest.createMockFromModule('graceful-fs'),
     readFileSync: jest.fn((path, options) => {
       if (mockFs[path]) {
         return options === 'utf8' ? mockFs[path] : Buffer.from(mockFs[path]);

packages/jest-haste-map/src/lib/__tests__/dependencyExtractor.test.js

@@ -243,4 +243,24 @@ describe('dependencyExtractor', () => {
     `;
     expect(extract(code)).toEqual(new Set(['dep1', 'dep2', 'dep3', 'dep4']));
   });
+
+  it('should extract dependencies from `jest.createMockFromModule` calls', () => {
+    const code = `
+      // Good
+      jest.createMockFromModule('dep1');
+      const dep2 = jest.createMockFromModule(
+        "dep2",
+      );
+      if (jest.createMockFromModule(\`dep3\`).cond) {}
+      jest
+        .requireMock('dep4');
+
+      // Bad
+      ${COMMENT_NO_NEG_LB} foo . jest.createMockFromModule('inv1')
+      xjest.createMockFromModule('inv2');
+      jest.createMockFromModulex('inv3');
+      jest.createMockFromModule('inv4', 'inv5');
+    `;
+    expect(extract(code)).toEqual(new Set(['dep1', 'dep2', 'dep3', 'dep4']));
+  });
 });

packages/jest-haste-map/src/lib/dependencyExtractor.ts

@@ -63,7 +63,7 @@ const IMPORT_OR_EXPORT_RE = createRegExp(
 const JEST_EXTENSIONS_RE = createRegExp(
   [
     ...functionCallStart(
-      'jest\\s*\\.\\s*(?:requireActual|requireMock|genMockFromModule)',
+      'jest\\s*\\.\\s*(?:requireActual|requireMock|genMockFromModule|createMockFromModule)',
     ),
     CAPTURE_STRING_LITERAL(1),
     WHITESPACE,

packages/jest-regex-util/src/__tests__/index.test.ts

@@ -10,7 +10,10 @@ describe('replacePathSepForRegex()', () => {
 
   describe('posix', () => {
     beforeAll(() => {
-      jest.mock('path', () => ({...jest.genMockFromModule('path'), sep: '/'}));
+      jest.mock('path', () => ({
+        ...jest.createMockFromModule('path'),
+        sep: '/',
+      }));
       jest.isolateModules(() => {
         replacePathSepForRegex = require('../').replacePathSepForRegex;
       });
@@ -24,7 +27,10 @@ describe('replacePathSepForRegex()', () => {
 
   describe('win32', () => {
     beforeAll(() => {
-      jest.mock('path', () => ({...jest.genMockFromModule('path'), sep: '\\'}));
+      jest.mock('path', () => ({
+        ...jest.createMockFromModule('path'),
+        sep: '\\',
+      }));
       jest.isolateModules(() => {
         replacePathSepForRegex = require('../').replacePathSepForRegex;
       });

packages/jest-reporters/src/__tests__/coverage_reporter.test.js

@@ -13,7 +13,7 @@ jest
     summarizers: {pkg: jest.fn(() => ({visit: jest.fn()}))},
   }))
   .mock('istanbul-reports', () => ({
-    ...jest.genMockFromModule('istanbul-reports'),
+    ...jest.createMockFromModule('istanbul-reports'),
     create: jest.fn(() => ({execute: jest.fn()})),
   }));
 

packages/jest-runtime/src/__tests__/runtime_gen_mock_from_module.test.js renamed to packages/jest-runtime/src/__tests__/runtime_create_mock_from_module.test.js

@@ -19,7 +19,7 @@ describe('Runtime', () => {
     createRuntime = require('createRuntime');
   });
 
-  describe('genMockFromModule', () => {
+  describe('createMockFromModule', () => {
     it('does not cause side effects in the rest of the module system when generating a mock', () =>
       createRuntime(__filename).then(runtime => {
         const testRequire = runtime.requireModule.bind(
@@ -33,7 +33,7 @@ describe('Runtime', () => {
         expect(origModuleStateValue).toBe('default');
 
         // Generate a mock for a module with side effects
-        const mock = module.jest.genMockFromModule('ModuleWithSideEffects');
+        const mock = module.jest.createMockFromModule('ModuleWithSideEffects');
 
         // Make sure we get a mock.
         expect(mock.fn()).toBe(undefined);
@@ -43,8 +43,8 @@ describe('Runtime', () => {
     it('resolves mapped modules correctly', () =>
       createRuntime(__filename, {moduleNameMapper}).then(runtime => {
         const root = runtime.requireModule(runtime.__mockRootPath);
-        const mockModule = root.jest.genMockFromModule(
-          'module/name/genMockFromModule',
+        const mockModule = root.jest.createMockFromModule(
+          'module/name/createMockFromModule',
         );
 
         expect(mockModule.test.mock).toBeTruthy();
@@ -59,7 +59,7 @@ describe('Runtime', () => {
       );
 
       const module = testRequire('RegularModule');
-      const mockModule = module.jest.genMockFromModule('RegularModule');
+      const mockModule = module.jest.createMockFromModule('RegularModule');
       const testObjectPrototype = Object.getPrototypeOf(module.object);
       const mockObjectPrototype = Object.getPrototypeOf(mockModule.object);
       expect(mockObjectPrototype).toBe(testObjectPrototype);

packages/jest-runtime/src/__tests__/test_root/mapped_module_genMockFromModule.js renamed to packages/jest-runtime/src/__tests__/test_root/mapped_module_createMockFromModule.js

@@ -1483,6 +1483,8 @@ class Runtime {
       autoMockOn: enableAutomock,
       clearAllMocks,
       clearAllTimers: () => _getFakeTimers().clearAllTimers(),
+      createMockFromModule: (moduleName: string) =>
+        this._generateMock(from, moduleName),
       deepUnmock,
       disableAutomock,
       doMock: mock,

packages/jest-runtime/src/index.ts

@@ -6,7 +6,7 @@
  */
 
 jest.mock('graceful-fs', () => ({
-  ...jest.genMockFromModule<typeof import('fs')>('fs'),
+  ...jest.createMockFromModule<typeof import('fs')>('fs'),
   existsSync: jest.fn().mockReturnValue(true),
   readdirSync: jest.fn().mockReturnValue([]),
   statSync: jest.fn(filePath => ({

packages/jest-snapshot/src/__tests__/inline_snapshots.test.ts

@@ -6,7 +6,7 @@
  */
 
 jest.mock('graceful-fs', () => ({
-  ...jest.genMockFromModule<typeof import('fs')>('fs'),
+  ...jest.createMockFromModule<typeof import('fs')>('fs'),
   existsSync: jest.fn().mockReturnValue(true),
 }));
 

packages/jest-snapshot/src/__tests__/utils.test.ts

@@ -11,7 +11,7 @@ import getCallsite from '../getCallsite';
 
 // Node 10.5.x compatibility
 jest.mock('graceful-fs', () => ({
-  ...jest.genMockFromModule<typeof import('fs')>('fs'),
+  ...jest.createMockFromModule<typeof import('fs')>('fs'),
   ReadStream: jest.requireActual('fs').ReadStream,
   WriteStream: jest.requireActual('fs').WriteStream,
 }));

packages/jest-source-map/src/__tests__/getCallsite.test.ts

@@ -10,7 +10,7 @@ import * as fs from 'graceful-fs';
 import TestSequencer from '../index';
 
 jest.mock('graceful-fs', () => ({
-  ...jest.genMockFromModule('fs'),
+  ...jest.createMockFromModule('fs'),
   existsSync: jest.fn(() => true),
   readFileSync: jest.fn(() => '{}'),
 }));

packages/jest-test-sequencer/src/__tests__/test_sequencer.test.js

@@ -13,7 +13,7 @@ jest
   .mock('graceful-fs', () =>
     // Node 10.5.x compatibility
     ({
-      ...jest.genMockFromModule('fs'),
+      ...jest.createMockFromModule('fs'),
       ReadStream: jest.requireActual('fs').ReadStream,
       WriteStream: jest.requireActual('fs').WriteStream,
       readFileSync: jest.fn((path, options) => {