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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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