Remove mockFs dependency

Summary:
This is first PR from the series I am going to be sending as a result of fixing 0.50-stable test suite. This one removes `mockFS` dependency that has been causing failures on Node 6.x container.

Here's build before this change: https://circleci.com/gh/facebook/react-native/22529
Here's build after this change: https://circleci.com/gh/facebook/react-native/22538 (green)

Note that the CI may be still red as there are other PRs to be addressed. You can see this in the wild on 0.50.
Closes https://github.com/facebook/react-native/pull/16301

Differential Revision: D6031352

Pulled By: hramos

fbshipit-source-id: 5c97ae6c87864c094e29e5d8987521071c67f5bd

local-cli/__mocks__/fs.js

@@ -94,6 +94,9 @@ fs.readFileSync.mockImplementation(function(filepath, encoding) {
   if (isDirNode(node)) {
     throw new Error('Error readFileSync a dir: ' + filepath);
   }
+  if (Buffer.isBuffer(node) && typeof encoding !== 'undefined') {
+    return node.toString();
+  }
   return node;
 });
 
@@ -133,7 +136,12 @@ function fsError(code, message) {
 }
 
 function isDirNode(node) {
-  return node && typeof node === 'object' && node.SYMLINK == null;
+  return (
+    node &&
+    typeof node === 'object' &&
+    node.SYMLINK == null &&
+    Buffer.isBuffer(node) === false
+  );
 }
 
 function readlinkSync(filepath) {

local-cli/core/__fixtures__/android.js

@@ -1,4 +1,4 @@
-const fs = require('fs');
+const fs = require.requireActual('fs');
 const path = require('path');
 
 const manifest = fs.readFileSync(path.join(__dirname, './files/AndroidManifest.xml'));

local-cli/core/__fixtures__/dependencies.js

@@ -1,4 +1,4 @@
-const fs = require('fs');
+const fs = require.requireActual('fs');
 const path = require('path');
 const android = require('./android');
 

local-cli/core/__fixtures__/ios.js

@@ -1,4 +1,4 @@
-const fs = require('fs');
+const fs = require.requireActual('fs');
 const path = require('path');
 
 exports.valid = {

local-cli/core/__fixtures__/projects.js

@@ -1,5 +1,3 @@
-const fs = require('fs');
-const path = require('path');
 const android = require('./android');
 const ios = require('./ios');
 

local-cli/core/__tests__/android/findAndroidAppFolder.spec.js

@@ -11,13 +11,15 @@
 
 'use strict';
 
+jest.mock('fs');
+
+const fs = require('fs');
 const findAndroidAppFolder = require('../../android/findAndroidAppFolder');
-const mockFS = require('mock-fs');
 const mocks = require('../../__fixtures__/android');
 
 describe('android::findAndroidAppFolder', () => {
   beforeAll(() => {
-    mockFS({
+    fs.__setMockFilesystem({
       empty: {},
       nested: {
         android: {
@@ -31,15 +33,11 @@ describe('android::findAndroidAppFolder', () => {
   });
 
   it('returns an android app folder if it exists in the given folder', () => {
-    expect(findAndroidAppFolder('flat')).toBe('android');
-    expect(findAndroidAppFolder('nested')).toBe('android/app');
+    expect(findAndroidAppFolder('/flat')).toBe('android');
+    expect(findAndroidAppFolder('/nested')).toBe('android/app');
   });
 
   it('returns `null` if there is no android app folder', () => {
-    expect(findAndroidAppFolder('empty')).toBeNull();
-  });
-
-  afterAll(() => {
-    mockFS.restore();
+    expect(findAndroidAppFolder('/empty')).toBeNull();
   });
 });

local-cli/core/__tests__/android/findManifest.spec.js

@@ -11,13 +11,15 @@
 
 'use strict';
 
+jest.mock('fs');
+
 const findManifest = require('../../android/findManifest');
-const mockFS = require('mock-fs');
+const fs = require('fs');
 const mocks = require('../../__fixtures__/android');
 
 describe('android::findManifest', () => {
   beforeAll(() => {
-    mockFS({
+    fs.__setMockFilesystem({
       empty: {},
       flat: {
         android: mocks.valid,
@@ -26,14 +28,10 @@ describe('android::findManifest', () => {
   });
 
   it('returns a manifest path if file exists in the folder', () => {
-    expect(typeof findManifest('flat')).toBe('string');
+    expect(typeof findManifest('/flat')).toBe('string');
   });
 
   it('returns `null` if there is no manifest in the folder', () => {
-    expect(findManifest('empty')).toBeNull();
-  });
-
-  afterAll(() => {
-    mockFS.restore();
+    expect(findManifest('/empty')).toBeNull();
   });
 });

local-cli/core/__tests__/android/findPackageClassName.spec.js

@@ -11,13 +11,15 @@
 
 'use strict';
 
+jest.mock('fs');
+
 const findPackageClassName = require('../../android/findPackageClassName');
-const mockFS = require('mock-fs');
+const fs = require('fs');
 const mocks = require('../../__fixtures__/android');
 
 describe('android::findPackageClassName', () => {
   beforeAll(() => {
-    mockFS({
+    fs.__setMockFilesystem({
       empty: {},
       flatJava: {
         android: mocks.valid,
@@ -29,22 +31,20 @@ describe('android::findPackageClassName', () => {
   });
 
   it('returns manifest content if file exists in the folder', () => {
-    expect(typeof findPackageClassName('flatJava')).toBe('string');
+    expect(typeof findPackageClassName('/flatJava')).toBe('string');
   });
 
   it('returns the name of the java class implementing ReactPackage', () => {
-    expect(findPackageClassName('flatJava')).toBe('SomeExampleJavaPackage');
+    expect(findPackageClassName('/flatJava')).toBe('SomeExampleJavaPackage');
   });
 
   it('returns the name of the kotlin class implementing ReactPackage', () => {
-    expect(findPackageClassName('flatKotlin')).toBe('SomeExampleKotlinPackage');
+    expect(findPackageClassName('/flatKotlin')).toBe(
+      'SomeExampleKotlinPackage',
+    );
   });
 
   it('returns `null` if there are no matches', () => {
-    expect(findPackageClassName('empty')).toBeNull();
-  });
-
-  afterAll(() => {
-    mockFS.restore();
+    expect(findPackageClassName('/empty')).toBeNull();
   });
 });

local-cli/core/__tests__/android/getDependencyConfig.spec.js

@@ -11,15 +11,17 @@
 
 'use strict';
 
+jest.mock('fs');
+
 const getDependencyConfig = require('../../android').dependencyConfig;
-const mockFS = require('mock-fs');
+const fs = require('fs');
 const mocks = require('../../__fixtures__/android');
 
 const userConfig = {};
 
 describe('android::getDependencyConfig', () => {
   beforeAll(() => {
-    mockFS({
+    fs.__setMockFilesystem({
       empty: {},
       nested: {
         android: {
@@ -38,27 +40,23 @@ describe('android::getDependencyConfig', () => {
   });
 
   it('returns an object with android project configuration', () => {
-    expect(getDependencyConfig('nested', userConfig)).not.toBeNull();
-    expect(typeof getDependencyConfig('nested', userConfig)).toBe('object');
+    expect(getDependencyConfig('/nested', userConfig)).not.toBeNull();
+    expect(typeof getDependencyConfig('/nested', userConfig)).toBe('object');
   });
 
   it('returns `null` if manifest file has not been found', () => {
-    expect(getDependencyConfig('empty', userConfig)).toBeNull();
+    expect(getDependencyConfig('/empty', userConfig)).toBeNull();
   });
 
   it('returns `null` if android project was not found', () => {
-    expect(getDependencyConfig('empty', userConfig)).toBeNull();
+    expect(getDependencyConfig('/empty', userConfig)).toBeNull();
   });
 
   it('returns `null` if android project does not contain ReactPackage', () => {
-    expect(getDependencyConfig('noPackage', userConfig)).toBeNull();
+    expect(getDependencyConfig('/noPackage', userConfig)).toBeNull();
   });
 
   it('returns `null` if it cannot find a packageClassName', () => {
-    expect(getDependencyConfig('corrupted', userConfig)).toBeNull();
-  });
-
-  afterAll(() => {
-    mockFS.restore();
+    expect(getDependencyConfig('/corrupted', userConfig)).toBeNull();
   });
 });

local-cli/core/__tests__/android/getProjectConfig.spec.js

@@ -11,13 +11,15 @@
 
 'use strict';
 
+jest.mock('fs');
+
 const getProjectConfig = require('../../android').projectConfig;
-const mockFS = require('mock-fs');
+const fs = require('fs');
 const mocks = require('../../__fixtures__/android');
 
 describe('android::getProjectConfig', () => {
   beforeAll(() => {
-    mockFS({
+    fs.__setMockFilesystem({
       empty: {},
       nested: {
         android: {
@@ -38,7 +40,7 @@ describe('android::getProjectConfig', () => {
 
   it("returns `null` if manifest file hasn't been found", () => {
     const userConfig = {};
-    const folder = 'noManifest';
+    const folder = '/noManifest';
 
     expect(getProjectConfig(folder, userConfig)).toBeNull();
   });
@@ -46,7 +48,7 @@ describe('android::getProjectConfig', () => {
   describe('returns an object with android project configuration for', () => {
     it('nested structure', () => {
       const userConfig = {};
-      const folder = 'nested';
+      const folder = '/nested';
 
       expect(getProjectConfig(folder, userConfig)).not.toBeNull();
       expect(typeof getProjectConfig(folder, userConfig)).toBe('object');
@@ -54,7 +56,7 @@ describe('android::getProjectConfig', () => {
 
     it('flat structure', () => {
       const userConfig = {};
-      const folder = 'flat';
+      const folder = '/flat';
 
       expect(getProjectConfig(folder, userConfig)).not.toBeNull();
       expect(typeof getProjectConfig(folder, userConfig)).toBe('object');
@@ -64,7 +66,7 @@ describe('android::getProjectConfig', () => {
       const userConfig = {
         manifestPath: 'src/main/AndroidManifest.xml',
       };
-      const folder = 'multiple';
+      const folder = '/multiple';
 
       expect(getProjectConfig(folder, userConfig)).not.toBeNull();
       expect(typeof getProjectConfig(folder, userConfig)).toBe('object');
@@ -73,12 +75,8 @@ describe('android::getProjectConfig', () => {
 
   it('should return `null` if android project was not found', () => {
     const userConfig = {};
-    const folder = 'empty';
+    const folder = '/empty';
 
     expect(getProjectConfig(folder, userConfig)).toBeNull();
   });
-
-  afterAll(() => {
-    mockFS.restore();
-  });
 });

local-cli/core/__tests__/android/readManifest.spec.js

@@ -11,14 +11,16 @@
 
 'use strict';
 
+jest.mock('fs');
+
 const findManifest = require('../../android/findManifest');
 const readManifest = require('../../android/readManifest');
-const mockFS = require('mock-fs');
+const fs = require('fs');
 const mocks = require('../../__fixtures__/android');
 
 describe('android::readManifest', () => {
   beforeAll(() => {
-    mockFS({
+    fs.__setMockFilesystem({
       empty: {},
       nested: {
         android: {
@@ -29,19 +31,15 @@ describe('android::readManifest', () => {
   });
 
   it('returns manifest content if file exists in the folder', () => {
-    const manifestPath = findManifest('nested');
+    const manifestPath = findManifest('/nested');
     expect(readManifest(manifestPath)).not.toBeNull();
     expect(typeof readManifest(manifestPath)).toBe('object');
   });
 
   it('throws an error if there is no manifest in the folder', () => {
-    const fakeManifestPath = findManifest('empty');
+    const fakeManifestPath = findManifest('/empty');
     expect(() => {
       readManifest(fakeManifestPath);
     }).toThrow();
   });
-
-  afterAll(() => {
-    mockFS.restore();
-  });
 });

local-cli/core/__tests__/findAssets.spec.js

@@ -11,24 +11,26 @@
 
 'use strict';
 
+jest.mock('fs');
+
 const findAssets = require('../findAssets');
 const dependencies = require('../__fixtures__/dependencies');
-const mockFs = require('mock-fs');
+const fs = require('fs');
 
 describe('findAssets', () => {
   beforeEach(() => {
-    mockFs({testDir: dependencies.withAssets});
+    fs.__setMockFilesystem({testDir: dependencies.withAssets});
   });
 
   it('returns an array of all files in given folders', () => {
-    const assets = findAssets('testDir', ['fonts', 'images']);
+    const assets = findAssets('/testDir', ['fonts', 'images']);
 
     expect(Array.isArray(assets)).toBeTruthy();
     expect(assets).toHaveLength(3);
   });
 
   it('prepends assets paths with the folder path', () => {
-    const assets = findAssets('testDir', ['fonts', 'images']);
+    const assets = findAssets('/testDir', ['fonts', 'images']);
 
     assets.forEach(assetPath => {
       expect(assetPath).toContain('testDir');
@@ -36,10 +38,6 @@ describe('findAssets', () => {
   });
 
   it('returns an empty array if given assets are null', () => {
-    expect(findAssets('testDir', null)).toHaveLength(0);
-  });
-
-  afterEach(() => {
-    mockFs.restore();
+    expect(findAssets('/testDir', null)).toHaveLength(0);
   });
 });

local-cli/core/__tests__/ios/findProject.spec.js

@@ -11,49 +11,51 @@
 
 'use strict';
 
+jest.mock('fs');
+
 const findProject = require('../../ios/findProject');
-const mockFS = require('mock-fs');
+const fs = require('fs');
 const projects = require('../../__fixtures__/projects');
 const ios = require('../../__fixtures__/ios');
 
 describe('ios::findProject', () => {
   it('returns path to xcodeproj if found', () => {
-    mockFS(projects.flat);
-    expect(findProject('')).not.toBeNull();
+    fs.__setMockFilesystem(projects.flat);
+    expect(findProject('/')).not.toBeNull();
   });
 
   it('returns null if there are no projects', () => {
-    mockFS({testDir: projects});
-    expect(findProject('')).toBeNull();
+    fs.__setMockFilesystem({testDir: projects});
+    expect(findProject('/')).toBeNull();
   });
 
   it('returns ios project regardless of its name', () => {
-    mockFS({ios: ios.validTestName});
-    expect(findProject('')).not.toBeNull();
+    fs.__setMockFilesystem({ios: ios.validTestName});
+    expect(findProject('/')).not.toBeNull();
   });
 
   it('ignores node_modules', () => {
-    mockFS({node_modules: projects.flat});
-    expect(findProject('')).toBeNull();
+    fs.__setMockFilesystem({node_modules: projects.flat});
+    expect(findProject('/')).toBeNull();
   });
 
   it('ignores Pods', () => {
-    mockFS({Pods: projects.flat});
-    expect(findProject('')).toBeNull();
+    fs.__setMockFilesystem({Pods: projects.flat});
+    expect(findProject('/')).toBeNull();
   });
 
   it('ignores Pods inside `ios` folder', () => {
-    mockFS({
+    fs.__setMockFilesystem({
       ios: {
         Pods: projects.flat,
         DemoApp: projects.flat.ios,
       },
     });
-    expect(findProject('')).toBe('ios/DemoApp/demoProject.xcodeproj');
+    expect(findProject('/')).toBe('ios/DemoApp/demoProject.xcodeproj');
   });
 
   it('ignores xcodeproj from example folders', () => {
-    mockFS({
+    fs.__setMockFilesystem({
       examples: projects.flat,
       Examples: projects.flat,
       example: projects.flat,
@@ -61,11 +63,11 @@ describe('ios::findProject', () => {
       Zpp: projects.flat,
     });
 
-    expect(findProject('').toLowerCase()).not.toContain('example');
+    expect(findProject('/').toLowerCase()).not.toContain('example');
   });
 
   it('ignores xcodeproj from sample folders', () => {
-    mockFS({
+    fs.__setMockFilesystem({
       samples: projects.flat,
       Samples: projects.flat,
       sample: projects.flat,
@@ -73,11 +75,11 @@ describe('ios::findProject', () => {
       Zpp: projects.flat,
     });
 
-    expect(findProject('').toLowerCase()).not.toContain('sample');
+    expect(findProject('/').toLowerCase()).not.toContain('sample');
   });
 
   it('ignores xcodeproj from test folders at any level', () => {
-    mockFS({
+    fs.__setMockFilesystem({
       test: projects.flat,
       IntegrationTests: projects.flat,
       tests: projects.flat,
@@ -87,10 +89,6 @@ describe('ios::findProject', () => {
       },
     });
 
-    expect(findProject('').toLowerCase()).not.toContain('test');
-  });
-
-  afterEach(() => {
-    mockFS.restore();
+    expect(findProject('/').toLowerCase()).not.toContain('test');
   });
 });

local-cli/core/__tests__/ios/getProjectConfig.spec.js

@@ -11,32 +11,34 @@
 
 'use strict';
 
+jest.mock('fs');
+
 const getProjectConfig = require('../../ios').projectConfig;
-const mockFS = require('mock-fs');
+const fs = require('fs');
 const projects = require('../../__fixtures__/projects');
 
 describe('ios::getProjectConfig', () => {
   const userConfig = {};
 
   beforeEach(() => {
-    mockFS({testDir: projects});
+    fs.__setMockFilesystem({testDir: projects});
   });
 
   it('returns an object with ios project configuration', () => {
-    const folder = 'testDir/nested';
+    const folder = '/testDir/nested';
 
     expect(getProjectConfig(folder, userConfig)).not.toBeNull();
     expect(typeof getProjectConfig(folder, userConfig)).toBe('object');
   });
 
   it('returns `null` if ios project was not found', () => {
-    const folder = 'testDir/empty';
+    const folder = '/testDir/empty';
 
     expect(getProjectConfig(folder, userConfig)).toBeNull();
   });
 
   it('returns normalized shared library names', () => {
-    const projectConfig = getProjectConfig('testDir/nested', {
+    const projectConfig = getProjectConfig('/testDir/nested', {
       sharedLibraries: ['libc++', 'libz.tbd', 'HealthKit', 'HomeKit.framework'],
     });
 
@@ -47,8 +49,4 @@ describe('ios::getProjectConfig', () => {
       'HomeKit.framework',
     ]);
   });
-
-  afterEach(() => {
-    mockFS.restore();
-  });
 });

package.json

@@ -200,7 +200,6 @@
     "eslint-plugin-react": "^7.2.1",
     "flow-bin": "^0.56.0",
     "jest": "^21",
-    "mock-fs": "^4.4.1",
     "prettier": "1.7.0",
     "react": "16.0.0",
     "react-test-renderer": "16.0.0",