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How to use __setMockFiles method in Jest

Best JavaScript code snippet using jest

babel-plugin-extension-resolver.test.js

Source:babel-plugin-extension-resolver.test.js

...27      await transformAsync('import path from "path";', options)28    ).toHaveProperty('code', 'import path from "path";');29  });30  it('finds .js files', async () => {31    fs.__setMockFiles([32      '/path/to/src/other.js',33      '/path/to/src/other.ts',34      '/path/to/src/other.tsx',35    ]);36    expect(37      await transformAsync('import other from "./other";', options)38    ).toHaveProperty('code', 'import other from "./other.js";');39  });40  it('finds .ts files', async () => {41    fs.__setMockFiles(['/path/to/src/other.ts', '/path/to/src/other.tsx']);42    expect(43      await transformAsync('import other from "./other";', options)44    ).toHaveProperty('code', 'import other from "./other.js";');45  });46  it('finds .tsx files', async () => {47    fs.__setMockFiles(['/path/to/src/other.tsx']);48    expect(49      await transformAsync('import other from "./other";', options)50    ).toHaveProperty('code', 'import other from "./other.js";');51  });52  it('finds files in parent directory', async () => {53    fs.__setMockFiles(['/path/to/other.js', '/path/to/src/other.js']);54    expect(55      await transformAsync('import other from "../other";', options)56    ).toHaveProperty('code', 'import other from "../other.js";');57  });58  it('finds files in child directory', async () => {59    fs.__setMockFiles(['/path/to/src/other.js', '/path/to/src/child/other.js']);60    expect(61      await transformAsync('import other from "./child/other";', options)62    ).toHaveProperty('code', 'import other from "./child/other.js";');63  });64  it('uses index file', async () => {65    fs.__setMockFiles(['/path/to/src/other/index.js']);66    expect(67      await transformAsync('import other from "./other";', options)68    ).toHaveProperty('code', 'import other from "./other/index.js";');69  });70  it('uses modulesToResolve', async () => {71    fs.__setMockFiles(['/path/to/src/other/index.js']);72    expect(73      await transformAsync(74        'import index from "instantsearch.js/es/widgets/index/index";\n' +75          'import root from "instantsearch.js";\n' +76          'import other from "different-module/other";',77        options78      )79    ).toHaveProperty(80      'code',81      'import index from "instantsearch.js/es/widgets/index/index.js";\n' +82        'import root from "instantsearch.js";\n' +83        'import other from "different-module/other";'84    );85  });86  it('works with multiple imports', async () => {87    fs.__setMockFiles(['/path/to/src/other.js', '/path/to/src/another.js']);88    expect(89      await transformAsync(90        'import other from "./other";\nimport another from "./another";',91        options92      )93    ).toHaveProperty(94      'code',95      'import other from "./other.js";\nimport another from "./another.js";'96    );97  });98  it('works with export from', async () => {99    fs.__setMockFiles(['/path/to/src/other.js']);100    expect(101      await transformAsync('export * from "./other"', options)102    ).toHaveProperty('code', 'export * from "./other.js";');103  });104  it('ignores require()', async () => {105    fs.__setMockFiles(['/path/to/src/other.js', '/path/to/src/another.js']);106    expect(await transformAsync('require("./other");', options)).toHaveProperty(107      'code',108      'require("./other");'109    );110  });111  it('ignores other function calls', async () => {112    fs.__setMockFiles(['/path/to/src/other.js']);113    expect(114      await transformAsync('requireOOPS("./other");', options)115    ).toHaveProperty('code', 'requireOOPS("./other");');116  });117  it('errors if file not found', async () => {118    fs.__setMockFiles([]);119    await expect(120      transformAsync('import other from "./other";', options)121    ).rejects.toThrow(122      '/path/to/src/file.js: import for "./other" could not be resolved'123    );124  });125  it('errors if module file not found', async () => {126    fs.__setMockFiles([]);127    await expect(128      transformAsync(129        'import other from "instantsearch.js/non-existing-folder-this-can-never-exist/qsdf/gh/jklm";',130        options131      )132    ).rejects.toThrow(133      /\/path\/to\/src\/file.js: Cannot find module 'instantsearch.js\/non-existing-folder-this-can-never-exist\/qsdf\/gh\/jklm' from '/134    );135  });...

extension-resolver.test.js

Source:extension-resolver.test.js

...27      await transformAsync('import path from "path";', options)28    ).toHaveProperty('code', 'import path from "path";');29  });30  it('finds .js files', async () => {31    fs.__setMockFiles([32      '/path/to/src/other.js',33      '/path/to/src/other.ts',34      '/path/to/src/other.tsx',35    ]);36    expect(37      await transformAsync('import other from "./other";', options)38    ).toHaveProperty('code', 'import other from "./other.js";');39  });40  it('finds .ts files', async () => {41    fs.__setMockFiles(['/path/to/src/other.ts', '/path/to/src/other.tsx']);42    expect(43      await transformAsync('import other from "./other";', options)44    ).toHaveProperty('code', 'import other from "./other.js";');45  });46  it('finds .tsx files', async () => {47    fs.__setMockFiles(['/path/to/src/other.tsx']);48    expect(49      await transformAsync('import other from "./other";', options)50    ).toHaveProperty('code', 'import other from "./other.js";');51  });52  it('finds files in parent directory', async () => {53    fs.__setMockFiles(['/path/to/other.js', '/path/to/src/other.js']);54    expect(55      await transformAsync('import other from "../other";', options)56    ).toHaveProperty('code', 'import other from "../other.js";');57  });58  it('finds files in child directory', async () => {59    fs.__setMockFiles(['/path/to/src/other.js', '/path/to/src/child/other.js']);60    expect(61      await transformAsync('import other from "./child/other";', options)62    ).toHaveProperty('code', 'import other from "./child/other.js";');63  });64  it('uses index file', async () => {65    fs.__setMockFiles(['/path/to/src/other/index.js']);66    expect(67      await transformAsync('import other from "./other";', options)68    ).toHaveProperty('code', 'import other from "./other/index.js";');69  });70  it('uses modulesToResolve', async () => {71    fs.__setMockFiles(['/path/to/src/other/index.js']);72    expect(73      await transformAsync(74        'import index from "instantsearch.js/es/widgets/index/index";\n' +75          'import root from "instantsearch.js";\n' +76          'import other from "different-module/other";',77        options78      )79    ).toHaveProperty(80      'code',81      'import index from "instantsearch.js/es/widgets/index/index.js";\n' +82        'import root from "instantsearch.js";\n' +83        'import other from "different-module/other";'84    );85  });86  it('works with multiple imports', async () => {87    fs.__setMockFiles(['/path/to/src/other.js', '/path/to/src/another.js']);88    expect(89      await transformAsync(90        'import other from "./other";\nimport another from "./another";',91        options92      )93    ).toHaveProperty(94      'code',95      'import other from "./other.js";\nimport another from "./another.js";'96    );97  });98  it('works with export from', async () => {99    fs.__setMockFiles(['/path/to/src/other.js']);100    expect(101      await transformAsync('export * from "./other"', options)102    ).toHaveProperty('code', 'export * from "./other.js";');103  });104  it('ignores require()', async () => {105    fs.__setMockFiles(['/path/to/src/other.js', '/path/to/src/another.js']);106    expect(await transformAsync('require("./other");', options)).toHaveProperty(107      'code',108      'require("./other");'109    );110  });111  it('ignores other function calls', async () => {112    fs.__setMockFiles(['/path/to/src/other.js']);113    expect(114      await transformAsync('requireOOPS("./other");', options)115    ).toHaveProperty('code', 'requireOOPS("./other");');116  });117  it('errors if file not found', async () => {118    fs.__setMockFiles([]);119    await expect(() =>120      transformAsync('import other from "./other";', options)121    ).rejects.toThrow(122      '/path/to/src/file.js: import for "./other" could not be resolved'123    );124  });125  it('errors if module file not found', async () => {126    fs.__setMockFiles([]);127    await expect(() =>128      transformAsync(129        'import other from "instantsearch.js/non-existing-folder-this-can-never-exist/qsdf/gh/jklm";',130        options131      )132    ).rejects.toThrow(133      "/path/to/src/file.js: Cannot find module 'instantsearch.js/non-existing-folder-this-can-never-exist/qsdf/gh/jklm' from 'scripts/babel/extension-resolver.js'"134    );135  });...

extension-resolver-test.js

Source:extension-resolver-test.js

...24      await transformAsync('import path from "path";', options)25    ).toHaveProperty('code', 'import path from "path";');26  });27  it('finds .js files', async () => {28    fs.__setMockFiles([29      '/path/to/src/other.js',30      '/path/to/src/other.ts',31      '/path/to/src/other.tsx',32    ]);33    expect(34      await transformAsync('import other from "./other";', options)35    ).toHaveProperty('code', 'import other from "./other.js";');36  });37  it('finds .ts files', async () => {38    fs.__setMockFiles(['/path/to/src/other.ts', '/path/to/src/other.tsx']);39    expect(40      await transformAsync('import other from "./other";', options)41    ).toHaveProperty('code', 'import other from "./other.js";');42  });43  it('finds .tsx files', async () => {44    fs.__setMockFiles(['/path/to/src/other.tsx']);45    expect(46      await transformAsync('import other from "./other";', options)47    ).toHaveProperty('code', 'import other from "./other.js";');48  });49  it('finds files in parent directory', async () => {50    fs.__setMockFiles(['/path/to/other.js', '/path/to/src/other.js']);51    expect(52      await transformAsync('import other from "../other";', options)53    ).toHaveProperty('code', 'import other from "../other.js";');54  });55  it('finds files in child directory', async () => {56    fs.__setMockFiles(['/path/to/src/other.js', '/path/to/src/child/other.js']);57    expect(58      await transformAsync('import other from "./child/other";', options)59    ).toHaveProperty('code', 'import other from "./child/other.js";');60  });61  it('uses index file', async () => {62    fs.__setMockFiles(['/path/to/src/other/index.js']);63    expect(64      await transformAsync('import other from "./other";', options)65    ).toHaveProperty('code', 'import other from "./other/index.js";');66  });67  it('works with multiple imports', async () => {68    fs.__setMockFiles(['/path/to/src/other.js', '/path/to/src/another.js']);69    expect(70      await transformAsync(71        'import other from "./other";\nimport another from "./another";',72        options73      )74    ).toHaveProperty(75      'code',76      'import other from "./other.js";\nimport another from "./another.js";'77    );78  });79  it('works with export from', async () => {80    fs.__setMockFiles(['/path/to/src/other.js']);81    expect(82      await transformAsync('export * from "./other"', options)83    ).toHaveProperty('code', 'export * from "./other.js";');84  });85  it('ignores require()', async () => {86    fs.__setMockFiles(['/path/to/src/other.js', '/path/to/src/another.js']);87    expect(await transformAsync('require("./other");', options)).toHaveProperty(88      'code',89      'require("./other");'90    );91  });92  it('ignores other function calls', async () => {93    fs.__setMockFiles(['/path/to/src/other.js']);94    expect(95      await transformAsync('requireOOPS("./other");', options)96    ).toHaveProperty('code', 'requireOOPS("./other");');97  });98  it('leaves as-is if file not found', async () => {99    fs.__setMockFiles([]);100    await expect(() =>101      transformAsync('import other from "./other";', options)102    ).rejects.toThrow(103      '/path/to/src/file.js: local import for "./other" could not be resolved'104    );105  });...

fs-extra.js

Source:fs-extra.js

...3// what the files on the "mock" filesystem should look like when any of the4// `fs` APIs are used.5let mockFiles = Object.create(null);6// eslint-disable-next-line no-underscore-dangle7function __setMockFiles(newMockFiles) {8  mockFiles = newMockFiles;9}10// A custom version of `readdirSync` that reads from the special mocked out11// file list set via __setMockFiles12const readFile = async (filePath) => mockFiles[filePath];13const readFileSync = (filePath = '') => mockFiles[filePath];14const existsSync = (filePath) => !!mockFiles[filePath];15const lstatSync = (filePath) => ({16  isFile: () => !!mockFiles[filePath],17});18// eslint-disable-next-line no-underscore-dangle19fs.__setMockFiles = __setMockFiles;20fs.readFile = readFile;21fs.readFileSync = readFileSync;...

messagesMock.js

Source:messagesMock.js

...4// This is a custom function that our tests can use during setup to specify5// what the files on the "mock" filesystem should look like when any of the6// `fs` APIs are used.7let mockFiles = Object.create(null);8function __setMockFiles(newMockFiles) {9  mockFiles = Object.create(null);10  for (const file in newMockFiles) {11    const dir = path.dirname(file);12    if (!mockFiles[dir]) {13      mockFiles[dir] = [];14    }15    mockFiles[dir].push(path.basename(file));16  }17}18// A custom version of `readdirSync` that reads from the special mocked out19// file list set via __setMockFiles20function readdirSync(directoryPath) {21  return mockFiles[directoryPath] || [];22}...

fs.js

Source:fs.js

...3// what the files on the "mock" filesystem should look like when any of the4// `fs` APIs are used.5let mockFiles = Object.create(null);6// eslint-disable-next-line no-underscore-dangle7function __setMockFiles(newMockFiles) {8  mockFiles = newMockFiles;9}10// A custom version of `readdirSync` that reads from the special mocked out11// file list set via __setMockFiles12const readFileSync = (filePath = '') => mockFiles[filePath];13const existsSync = (filePath) => !!mockFiles[filePath];14const lstatSync = (filePath) => ({15  isFile: () => !!mockFiles[filePath],16});17// eslint-disable-next-line no-underscore-dangle18fs.__setMockFiles = __setMockFiles;19fs.readFileSync = readFileSync;20fs.existsSync = existsSync;21fs.lstatSync = lstatSync;...

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