How to use generateEmptyCoverage method in Jest

Best JavaScript code snippet using jest

generateEmptyCoverage.test.js

Source:generateEmptyCoverage.test.js Github

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...33 module.exports = {34 a,35 };`;36 shouldInstrument.mockReturnValueOnce(true);37 const emptyCoverage = generateEmptyCoverage(38 src,39 filepath,40 makeGlobalConfig(),41 makeProjectConfig({42 cacheDirectory: os.tmpdir(),43 rootDir,44 transform: [['^.+\\.js$', require.resolve('babel-jest')]],45 }),46 );47 expect(emptyCoverage).not.toBeNull();48 expect(typeof emptyCoverage).toBe('object');49 let coverage = emptyCoverage.coverage;50 if (emptyCoverage.sourceMapPath) {51 coverageMap.addFileCoverage(emptyCoverage.coverage);52 sourceMapStore.registerURL(filepath, emptyCoverage.sourceMapPath);53 coverage = sourceMapStore.transformCoverage(coverageMap).map;54 }55 expect(coverage.data).toMatchSnapshot({path: expect.any(String)});56 });57 it('generates a null coverage result when using /* istanbul ignore file */', () => {58 const src = `59 /* istanbul ignore file */60 const a = (b, c) => {61 if (b) {62 return c;63 } else {64 return b;65 }66 };67 module.exports = { a };68 `;69 shouldInstrument.mockReturnValueOnce(true);70 const nullCoverage = generateEmptyCoverage(71 src,72 filepath,73 makeGlobalConfig(),74 makeProjectConfig({75 cacheDirectory: os.tmpdir(),76 rootDir,77 transform: [['^.+\\.js$', require.resolve('babel-jest')]],78 }),79 );80 expect(nullCoverage).toBeNull();81 });82 it('generates a null coverage result when collectCoverage global config is false', () => {83 const src = `84 const a = (b, c) => {85 if (b) {86 return c;87 } else {88 return b;89 }90 };91 module.exports = { a };92 `;93 shouldInstrument.mockReturnValueOnce(false);94 const nullCoverage = generateEmptyCoverage(95 src,96 filepath,97 makeGlobalConfig(),98 makeProjectConfig({99 cacheDirectory: os.tmpdir(),100 rootDir,101 transform: [['^.+\\.js$', require.resolve('babel-jest')]],102 }),103 );104 expect(nullCoverage).toBeNull();105 });...

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CoverageWorker.test.js

Source:CoverageWorker.test.js Github

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1/**2 * Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.3 *4 * This source code is licensed under the MIT license found in the5 * LICENSE file in the root directory of this source tree.6 */7'use strict';8jest.mock('graceful-fs').mock('../generateEmptyCoverage');9const globalConfig = {collectCoverage: true};10const config = {};11const workerOptions = {config, globalConfig, path: 'banana.js'};12let fs;13let generateEmptyCoverage;14let worker;15beforeEach(() => {16 jest.resetModules();17 fs = require('graceful-fs');18 generateEmptyCoverage = require('../generateEmptyCoverage').default;19 worker = require('../CoverageWorker').worker;20});21test('resolves to the result of generateEmptyCoverage upon success', async () => {22 expect.assertions(2);23 const validJS = 'function(){}';24 fs.readFileSync.mockImplementation(() => validJS);25 generateEmptyCoverage.mockImplementation(() => 42);26 const result = await worker(workerOptions);27 expect(generateEmptyCoverage).toBeCalledWith(28 validJS,29 'banana.js',30 globalConfig,31 config,32 undefined,33 undefined,34 );35 expect(result).toEqual(42);36});37test('throws errors on invalid JavaScript', async () => {38 expect.assertions(1);39 generateEmptyCoverage.mockImplementation(() => {40 throw new Error('SyntaxError');41 });42 // We intentionally expect the worker to fail!43 try {44 await worker(workerOptions);45 } catch (error) {46 expect(error).toBeInstanceOf(Error);47 }...

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coverage_worker.test.js

Source:coverage_worker.test.js Github

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1/**2 * Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.3 *4 * This source code is licensed under the MIT license found in the5 * LICENSE file in the root directory of this source tree.6 */7'use strict';8jest.mock('fs').mock('../../generateEmptyCoverage');9const globalConfig = {collectCoverage: true};10const config = {};11const workerOptions = {config, globalConfig, path: 'banana.js'};12let fs;13let generateEmptyCoverage;14let worker;15beforeEach(() => {16 jest.resetModules();17 fs = require('fs');18 generateEmptyCoverage = require('../../generateEmptyCoverage').default;19 worker = require('../coverage_worker').worker;20});21test('resolves to the result of generateEmptyCoverage upon success', async () => {22 expect.assertions(2);23 const validJS = 'function(){}';24 fs.readFileSync.mockImplementation(() => validJS);25 generateEmptyCoverage.mockImplementation(() => 42);26 const result = await worker(workerOptions);27 expect(generateEmptyCoverage).toBeCalledWith(28 validJS,29 'banana.js',30 globalConfig,31 config,32 );33 expect(result).toEqual(42);34});35test('throws errors on invalid JavaScript', async () => {36 expect.assertions(1);37 generateEmptyCoverage.mockImplementation(() => {38 throw new Error('SyntaxError');39 });40 // We intentionally expect the worker to fail!41 try {42 await worker(workerOptions);43 } catch (error) {44 expect(error).toBeInstanceOf(Error);45 }...

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26coverage_worker.test.js

Source:26coverage_worker.test.js Github

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1/**2 * Copyright (c) 2014-present, Facebook, Inc. All rights reserved.3 *4 * This source code is licensed under the MIT license found in the5 * LICENSE file in the root directory of this source tree.6 */7'use strict';8jest.mock('fs').mock('../../generateEmptyCoverage');9const globalConfig = {collectCoverage: true};10const config = {};11const workerOptions = {config, globalConfig, path: 'banana.js'};12let fs;13let generateEmptyCoverage;14let worker;15beforeEach(() => {16 jest.resetModules();17 fs = require('fs');18 generateEmptyCoverage = require('../../generateEmptyCoverage').default;19 worker = require('../coverage_worker').worker;20});21test('resolves to the result of generateEmptyCoverage upon success', async () => {22 expect.assertions(2);23 const validJS = 'function(){}';24 fs.readFileSync.mockImplementation(() => validJS);25 generateEmptyCoverage.mockImplementation(() => 42);26 const result = await worker(workerOptions);27 expect(generateEmptyCoverage).toBeCalledWith(28 validJS,29 'banana.js',30 globalConfig,31 config,32 );33 expect(result).toEqual(42);34});35test('throws errors on invalid JavaScript', async () => {36 expect.assertions(1);37 generateEmptyCoverage.mockImplementation(() => {38 throw new Error('SyntaxError');39 });40 // We intentionally expect the worker to fail!41 try {42 await worker(workerOptions);43 } catch (error) {44 expect(error).toBeInstanceOf(Error);45 }...

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CoverageWorker.js

Source:CoverageWorker.js Github

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...29callback) =>30{let config = _ref.config,globalConfig = _ref.globalConfig,path = _ref.path;31 try {32 const source = fs.readFileSync(path, 'utf8');33 const result = generateEmptyCoverage(source, path, globalConfig, config);34 callback(null, result);35 } catch (error) {36 callback(formatCoverageError(error, path), undefined);37 }...

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generateEmptyCoverage-test.js

Source:generateEmptyCoverage-test.js Github

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...27module.exports = {28 a,29};`;30it('generates an empty coverage object for a file without running it', () => {31 expect(generateEmptyCoverage(src, '/sum.js', {32 rootDir: os.tmpdir(),33 baseCacheDir: os.tmpdir(),34 cacheDirectory: os.tmpdir(),35 })).toMatchSnapshot();...

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coverage_worker.js

Source:coverage_worker.js Github

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...26 config,27 globalConfig,28 path,29}: CoverageWorkerData): ?CoverageWorkerResult {30 return generateEmptyCoverage(31 fs.readFileSync(path, 'utf8'),32 path,33 globalConfig,34 config,35 );...

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