How to use requireOrImportModule method in Jest

Best JavaScript code snippet using jest

runJest.js

Source:runJest.js

1'use strict';2Object.defineProperty(exports, '__esModule', {3  value: true4});5exports.default = runJest;6function path() {7  const data = _interopRequireWildcard(require('path'));8  path = function () {9    return data;10  };11  return data;12}13function _chalk() {14  const data = _interopRequireDefault(require('chalk'));15  _chalk = function () {16    return data;17  };18  return data;19}20function _exit() {21  const data = _interopRequireDefault(require('exit'));22  _exit = function () {23    return data;24  };25  return data;26}27function fs() {28  const data = _interopRequireWildcard(require('graceful-fs'));29  fs = function () {30    return data;31  };32  return data;33}34function _console() {35  const data = require('@jest/console');36  _console = function () {37    return data;38  };39  return data;40}41function _testResult() {42  const data = require('@jest/test-result');43  _testResult = function () {44    return data;45  };46  return data;47}48function _jestResolve() {49  const data = _interopRequireDefault(require('jest-resolve'));50  _jestResolve = function () {51    return data;52  };53  return data;54}55function _jestUtil() {56  const data = require('jest-util');57  _jestUtil = function () {58    return data;59  };60  return data;61}62function _jestWatcher() {63  const data = require('jest-watcher');64  _jestWatcher = function () {65    return data;66  };67  return data;68}69var _SearchSource = _interopRequireDefault(require('./SearchSource'));70var _TestScheduler = require('./TestScheduler');71var _collectHandles = _interopRequireDefault(require('./collectHandles'));72var _getNoTestsFoundMessage = _interopRequireDefault(73  require('./getNoTestsFoundMessage')74);75var _runGlobalHook = _interopRequireDefault(require('./runGlobalHook'));76function _interopRequireDefault(obj) {77  return obj && obj.__esModule ? obj : {default: obj};78}79function _getRequireWildcardCache(nodeInterop) {80  if (typeof WeakMap !== 'function') return null;81  var cacheBabelInterop = new WeakMap();82  var cacheNodeInterop = new WeakMap();83  return (_getRequireWildcardCache = function (nodeInterop) {84    return nodeInterop ? cacheNodeInterop : cacheBabelInterop;85  })(nodeInterop);86}87function _interopRequireWildcard(obj, nodeInterop) {88  if (!nodeInterop && obj && obj.__esModule) {89    return obj;90  }91  if (obj === null || (typeof obj !== 'object' && typeof obj !== 'function')) {92    return {default: obj};93  }94  var cache = _getRequireWildcardCache(nodeInterop);95  if (cache && cache.has(obj)) {96    return cache.get(obj);97  }98  var newObj = {};99  var hasPropertyDescriptor =100    Object.defineProperty && Object.getOwnPropertyDescriptor;101  for (var key in obj) {102    if (key !== 'default' && Object.prototype.hasOwnProperty.call(obj, key)) {103      var desc = hasPropertyDescriptor104        ? Object.getOwnPropertyDescriptor(obj, key)105        : null;106      if (desc && (desc.get || desc.set)) {107        Object.defineProperty(newObj, key, desc);108      } else {109        newObj[key] = obj[key];110      }111    }112  }113  newObj.default = obj;114  if (cache) {115    cache.set(obj, newObj);116  }117  return newObj;118}119/**120 * Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.121 *122 * This source code is licensed under the MIT license found in the123 * LICENSE file in the root directory of this source tree.124 */125const getTestPaths = async (126  globalConfig,127  source,128  outputStream,129  changedFiles,130  jestHooks,131  filter132) => {133  const data = await source.getTestPaths(globalConfig, changedFiles, filter);134  if (!data.tests.length && globalConfig.onlyChanged && data.noSCM) {135    new (_console().CustomConsole)(outputStream, outputStream).log(136      'Jest can only find uncommitted changed files in a git or hg ' +137        'repository. If you make your project a git or hg ' +138        'repository (`git init` or `hg init`), Jest will be able ' +139        'to only run tests related to files changed since the last ' +140        'commit.'141    );142  }143  const shouldTestArray = await Promise.all(144    data.tests.map(test =>145      jestHooks.shouldRunTestSuite({146        config: test.context.config,147        duration: test.duration,148        testPath: test.path149      })150    )151  );152  const filteredTests = data.tests.filter((_test, i) => shouldTestArray[i]);153  return {...data, allTests: filteredTests.length, tests: filteredTests};154};155const processResults = async (runResults, options) => {156  const {157    outputFile,158    json: isJSON,159    onComplete,160    outputStream,161    testResultsProcessor,162    collectHandles163  } = options;164  if (collectHandles) {165    runResults.openHandles = await collectHandles();166  } else {167    runResults.openHandles = [];168  }169  if (testResultsProcessor) {170    const processor = await (0, _jestUtil().requireOrImportModule)(171      testResultsProcessor172    );173    runResults = processor(runResults);174  }175  if (isJSON) {176    if (outputFile) {177      const cwd = (0, _jestUtil().tryRealpath)(process.cwd());178      const filePath = path().resolve(cwd, outputFile);179      fs().writeFileSync(180        filePath,181        JSON.stringify((0, _testResult().formatTestResults)(runResults))182      );183      outputStream.write(184        `Test results written to: ${path().relative(cwd, filePath)}\n`185      );186    } else {187      process.stdout.write(188        JSON.stringify((0, _testResult().formatTestResults)(runResults))189      );190    }191  }192  onComplete === null || onComplete === void 0193    ? void 0194    : onComplete(runResults);195};196const testSchedulerContext = {197  firstRun: true,198  previousSuccess: true199};200async function runJest({201  contexts,202  globalConfig,203  outputStream,204  testWatcher,205  jestHooks = new (_jestWatcher().JestHook)().getEmitter(),206  startRun,207  changedFilesPromise,208  onComplete,209  failedTestsCache,210  filter211}) {212  // Clear cache for required modules - there might be different resolutions213  // from Jest's config loading to running the tests214  _jestResolve().default.clearDefaultResolverCache();215  const Sequencer = await (0, _jestUtil().requireOrImportModule)(216    globalConfig.testSequencer217  );218  const sequencer = new Sequencer();219  let allTests = [];220  if (changedFilesPromise && globalConfig.watch) {221    const {repos} = await changedFilesPromise;222    const noSCM = Object.keys(repos).every(scm => repos[scm].size === 0);223    if (noSCM) {224      process.stderr.write(225        '\n' +226          _chalk().default.bold('--watch') +227          ' is not supported without git/hg, please use --watchAll ' +228          '\n'229      );230      (0, _exit().default)(1);231    }232  }233  const searchSources = contexts.map(234    context => new _SearchSource.default(context)235  );236  const testRunData = await Promise.all(237    contexts.map(async (context, index) => {238      const searchSource = searchSources[index];239      const matches = await getTestPaths(240        globalConfig,241        searchSource,242        outputStream,243        changedFilesPromise && (await changedFilesPromise),244        jestHooks,245        filter246      );247      allTests = allTests.concat(matches.tests);248      return {249        context,250        matches251      };252    })253  );254  allTests = await sequencer.sort(allTests);255  if (globalConfig.listTests) {256    const testsPaths = Array.from(new Set(allTests.map(test => test.path)));257    /* eslint-disable no-console */258    if (globalConfig.json) {259      console.log(JSON.stringify(testsPaths));260    } else {261      console.log(testsPaths.join('\n'));262    }263    /* eslint-enable */264    onComplete &&265      onComplete((0, _testResult().makeEmptyAggregatedTestResult)());266    return;267  }268  if (globalConfig.onlyFailures) {269    if (failedTestsCache) {270      allTests = failedTestsCache.filterTests(allTests);271    } else {272      allTests = await sequencer.allFailedTests(allTests);273    }274  }275  const hasTests = allTests.length > 0;276  if (!hasTests) {277    const noTestsFoundMessage = (0, _getNoTestsFoundMessage.default)(278      testRunData,279      globalConfig280    );281    if (282      globalConfig.passWithNoTests ||283      globalConfig.findRelatedTests ||284      globalConfig.lastCommit ||285      globalConfig.onlyChanged286    ) {287      new (_console().CustomConsole)(outputStream, outputStream).log(288        noTestsFoundMessage289      );290    } else {291      new (_console().CustomConsole)(outputStream, outputStream).error(292        noTestsFoundMessage293      );294      (0, _exit().default)(1);295    }296  } else if (297    allTests.length === 1 &&298    globalConfig.silent !== true &&299    globalConfig.verbose !== false300  ) {301    const newConfig = {...globalConfig, verbose: true};302    globalConfig = Object.freeze(newConfig);303  }304  let collectHandles;305  if (globalConfig.detectOpenHandles) {306    collectHandles = (0, _collectHandles.default)();307  }308  if (hasTests) {309    await (0, _runGlobalHook.default)({310      allTests,311      globalConfig,312      moduleName: 'globalSetup'313    });314  }315  if (changedFilesPromise) {316    const changedFilesInfo = await changedFilesPromise;317    if (changedFilesInfo.changedFiles) {318      testSchedulerContext.changedFiles = changedFilesInfo.changedFiles;319      const sourcesRelatedToTestsInChangedFilesArray = (320        await Promise.all(321          contexts.map(async (_, index) => {322            const searchSource = searchSources[index];323            return searchSource.findRelatedSourcesFromTestsInChangedFiles(324              changedFilesInfo325            );326          })327        )328      ).reduce((total, paths) => total.concat(paths), []);329      testSchedulerContext.sourcesRelatedToTestsInChangedFiles = new Set(330        sourcesRelatedToTestsInChangedFilesArray331      );332    }333  }334  const scheduler = await (0, _TestScheduler.createTestScheduler)(335    globalConfig,336    {337      startRun338    },339    testSchedulerContext340  );341  const results = await scheduler.scheduleTests(allTests, testWatcher);342  await sequencer.cacheResults(allTests, results);343  if (hasTests) {344    await (0, _runGlobalHook.default)({345      allTests,346      globalConfig,347      moduleName: 'globalTeardown'348    });349  }350  await processResults(results, {351    collectHandles,352    json: globalConfig.json,353    onComplete,354    outputFile: globalConfig.outputFile,355    outputStream,356    testResultsProcessor: globalConfig.testResultsProcessor357  });...

index.js

Source:index.js

1'use strict';2Object.defineProperty(exports, '__esModule', {3  value: true4});5Object.defineProperty(exports, 'ErrorWithStack', {6  enumerable: true,7  get: function () {8    return _ErrorWithStack.default;9  }10});11Object.defineProperty(exports, 'clearLine', {12  enumerable: true,13  get: function () {14    return _clearLine.default;15  }16});17Object.defineProperty(exports, 'convertDescriptorToString', {18  enumerable: true,19  get: function () {20    return _convertDescriptorToString.default;21  }22});23Object.defineProperty(exports, 'createDirectory', {24  enumerable: true,25  get: function () {26    return _createDirectory.default;27  }28});29Object.defineProperty(exports, 'deepCyclicCopy', {30  enumerable: true,31  get: function () {32    return _deepCyclicCopy.default;33  }34});35Object.defineProperty(exports, 'formatTime', {36  enumerable: true,37  get: function () {38    return _formatTime.default;39  }40});41Object.defineProperty(exports, 'globsToMatcher', {42  enumerable: true,43  get: function () {44    return _globsToMatcher.default;45  }46});47Object.defineProperty(exports, 'installCommonGlobals', {48  enumerable: true,49  get: function () {50    return _installCommonGlobals.default;51  }52});53Object.defineProperty(exports, 'interopRequireDefault', {54  enumerable: true,55  get: function () {56    return _interopRequireDefault.default;57  }58});59Object.defineProperty(exports, 'isInteractive', {60  enumerable: true,61  get: function () {62    return _isInteractive.default;63  }64});65Object.defineProperty(exports, 'isPromise', {66  enumerable: true,67  get: function () {68    return _isPromise.default;69  }70});71Object.defineProperty(exports, 'pluralize', {72  enumerable: true,73  get: function () {74    return _pluralize.default;75  }76});77exports.preRunMessage = void 0;78Object.defineProperty(exports, 'replacePathSepForGlob', {79  enumerable: true,80  get: function () {81    return _replacePathSepForGlob.default;82  }83});84Object.defineProperty(exports, 'requireOrImportModule', {85  enumerable: true,86  get: function () {87    return _requireOrImportModule.default;88  }89});90Object.defineProperty(exports, 'setGlobal', {91  enumerable: true,92  get: function () {93    return _setGlobal.default;94  }95});96exports.specialChars = void 0;97Object.defineProperty(exports, 'testPathPatternToRegExp', {98  enumerable: true,99  get: function () {100    return _testPathPatternToRegExp.default;101  }102});103Object.defineProperty(exports, 'tryRealpath', {104  enumerable: true,105  get: function () {106    return _tryRealpath.default;107  }108});109var _clearLine = _interopRequireDefault2(require('./clearLine'));110var _createDirectory = _interopRequireDefault2(require('./createDirectory'));111var _ErrorWithStack = _interopRequireDefault2(require('./ErrorWithStack'));112var _installCommonGlobals = _interopRequireDefault2(113  require('./installCommonGlobals')114);115var _interopRequireDefault = _interopRequireDefault2(116  require('./interopRequireDefault')117);118var _isInteractive = _interopRequireDefault2(require('./isInteractive'));119var _isPromise = _interopRequireDefault2(require('./isPromise'));120var _setGlobal = _interopRequireDefault2(require('./setGlobal'));121var _deepCyclicCopy = _interopRequireDefault2(require('./deepCyclicCopy'));122var _convertDescriptorToString = _interopRequireDefault2(123  require('./convertDescriptorToString')124);125var _specialChars = _interopRequireWildcard(require('./specialChars'));126exports.specialChars = _specialChars;127var _replacePathSepForGlob = _interopRequireDefault2(128  require('./replacePathSepForGlob')129);130var _testPathPatternToRegExp = _interopRequireDefault2(131  require('./testPathPatternToRegExp')132);133var _globsToMatcher = _interopRequireDefault2(require('./globsToMatcher'));134var _preRunMessage = _interopRequireWildcard(require('./preRunMessage'));135exports.preRunMessage = _preRunMessage;136var _pluralize = _interopRequireDefault2(require('./pluralize'));137var _formatTime = _interopRequireDefault2(require('./formatTime'));138var _tryRealpath = _interopRequireDefault2(require('./tryRealpath'));139var _requireOrImportModule = _interopRequireDefault2(140  require('./requireOrImportModule')141);142function _getRequireWildcardCache(nodeInterop) {143  if (typeof WeakMap !== 'function') return null;144  var cacheBabelInterop = new WeakMap();145  var cacheNodeInterop = new WeakMap();146  return (_getRequireWildcardCache = function (nodeInterop) {147    return nodeInterop ? cacheNodeInterop : cacheBabelInterop;148  })(nodeInterop);149}150function _interopRequireWildcard(obj, nodeInterop) {151  if (!nodeInterop && obj && obj.__esModule) {152    return obj;153  }154  if (obj === null || (typeof obj !== 'object' && typeof obj !== 'function')) {155    return {default: obj};156  }157  var cache = _getRequireWildcardCache(nodeInterop);158  if (cache && cache.has(obj)) {159    return cache.get(obj);160  }161  var newObj = {};162  var hasPropertyDescriptor =163    Object.defineProperty && Object.getOwnPropertyDescriptor;164  for (var key in obj) {165    if (key !== 'default' && Object.prototype.hasOwnProperty.call(obj, key)) {166      var desc = hasPropertyDescriptor167        ? Object.getOwnPropertyDescriptor(obj, key)168        : null;169      if (desc && (desc.get || desc.set)) {170        Object.defineProperty(newObj, key, desc);171      } else {172        newObj[key] = obj[key];173      }174    }175  }176  newObj.default = obj;177  if (cache) {178    cache.set(obj, newObj);179  }180  return newObj;181}182function _interopRequireDefault2(obj) {183  return obj && obj.__esModule ? obj : {default: obj};...

Project.js

Source:Project.js

1import { writeMergePackageJson } from '@dbux/cli/lib/package-util';2import Project from '../../projectLib/Project';3import { buildJestRunBugCommand } from '../../util/jestUtil';4/** @typedef {import('../../projectLib/ExerciseConfig').ExerciseConfig} ExerciseConfig */5export default class JavascriptAlgorithmProject extends Project {6  gitRemote = 'trekhleb/javascript-algorithms.git';7  gitCommit = '9bb60fa';8  rmFiles = [9    'package-lock.json',10    '.babelrc',       // we need babel.config.js instead11    '.husky'   // unwanted commit hooks12  ];13  runCfg = {14  };15  async beforeInstall() {16    // remove husky from package.json17    writeMergePackageJson(this.projectPath, { scripts: { prepare: '' } });18  }19  canRunExercise(config) {20    return !!config.testFilePaths;21  }22  decorateExercise(config) {23    return {24      // id: i + 1,25      // name: config.testName,26      // description: bug.testName,27      runArgs: [28        '--runInBand', // -i29        '-t',30        /**31         * @see https://jestjs.io/docs/cli#--testnamepatternregex32         */33        `"${config.testNamePattern}"`,34        '--runTestsByPath',35        config.testFilePaths.join(' ')36      ],37      enableSourceMaps: false,38      ...config,39      // testFilePaths: bug.testFilePaths.map(p => `./${p}`)40    };41  }42  async selectExercise(exercise) {43    // nothing to do here44  }45  async runCommand(bug, cfg) {46    const { projectPath } = this;47    // const bugArgs = this.getMochaRunArgs(bug);48    const testCfg = this.getJestCfg(bug, [49      '--setupFilesAfterEnv ./dbuxJestSetup.js',50      '--colors'51    ]);52    /**53     * TODO: find `describe`54     * 55     * * for now, we cannot find the definition of the `describe` function56     * * or maybe some other way to determine how tests are registered and sorted?57     * * -> it's coming from `@jest/core` -> `runWithoutWatch`58     * * -> `nonFlagArgs` contains the test files (from `jest.config.js`)59     * * -> have not found the actual tests yet.60     * * -> for that, maybe console log tracing will help?61     * * if `jasmine` enabled -> https://github.com/facebook/jest/blob/e0b33b74b5afd738edc183858b5c34053cfc26dd/packages/jest-jasmine2/src/jasmine/Env.ts#L38362     */63    cfg = {64      ...cfg,65      ...testCfg,66      cwd: projectPath,67      /**68       * NOTE: Jest has a two-layer approach, where the first layer bootstraps Jest,69       *  and the second layer runs inside a VM (after running through `@jest/transform` and more).70       * We found that, if we run `Jest` with `@babel/register`, 71       * Jest's own transformer doubles up the instrumentation on some of the code.72       * 73       * One possible solution: make sure, each library (or specific files) only runs in one of the layers, so74       * transformation never doubles up.75       *76       * Libraries that might be exclusively used in test layer:77       *   * jest-runner78       *   * jest-environment-node79       * Libraries that run code in both layers:80       *   * jest-circus81       */82      // dbuxJs: null,83      dbuxArgs: [84        cfg.dbuxArgs,85        '--pw=jest[-]circus,jest[-]runner,jest[-]runtime,jest[-]environment[-]node,jest[-]jasmine2', //,@jest/core',86        //   /**87        //    * babel, debug, pirates, resolve, import, jest-resolve, jest-runtime, @jest/transform, regenerator-transform, source-map*: very likely to mess things up.88        //    * human-signals, jest-haste-map, safe-buffer: caused weird problems?89        //    * gensync: seems to be connected to regenerator-transform?90        //    * graceful-fs: messy polyfilles91        //    * 92        //    * Uninteresting libraries:93        //    * browserslist, react-is94        //    * jsesc: data conversion95        //    */96        //   // eslint-disable-next-line max-len97        //   '--pb=babel[-].*,graceful[-]fs,require.*,resolve.*,import.*,locate.*,pretty[-]format,jest[-]config,jest[-]validate,jest[-]resolve.*,jest[-]runtime,@jest/transform,regenerator[-]transform,.*source[-]map,browserslist,human[-]signals,react[-]is,jest[-]haste[-]map,@jest/reporters,debug,pirates,jsesc,gensync,safe-buffer',98        //   '--fw=.*',99        //   '--fb=requireOrImportModule\\.js',100        //   // '--runtime="{\\"tracesDisabled\\":1}"'101      ].join(' ')102    };103    /**104     * NOTES105     * 106     * 1. node_modules/jest-util/build/index.js:38 getter might cause infinite loop (but does not for now)107     */108    return buildJestRunBugCommand(cfg);109  }...

requireOrImportModule.js

Source:requireOrImportModule.js

...28 *29 * This source code is licensed under the MIT license found in the30 * LICENSE file in the root directory of this source tree.31 */32async function requireOrImportModule(33  filePath,34  applyInteropRequireDefault = true35) {36  if (!(0, _path().isAbsolute)(filePath) && filePath[0] === '.') {37    throw new Error(38      `Jest: requireOrImportModule path must be absolute, was "${filePath}"`39    );40  }41  try {42    const requiredModule = require(filePath);43    if (!applyInteropRequireDefault) {44      return requiredModule;45    }46    return (0, _interopRequireDefault.default)(requiredModule).default;...

Jest Testing Tutorial

LambdaTest’s Jest Testing Tutorial covers step-by-step guides around Jest with code examples to help you be proficient with the Jest framework. The Jest tutorial has chapters to help you learn right from the basics of Jest framework to code-based tutorials around testing react apps with Jest, perform snapshot testing, import ES modules and more.

Chapters

What is Jest Framework
Advantages of Jest - Jest has 3,898,000 GitHub repositories, as mentioned on its official website. Learn what makes Jest special and why Jest has gained popularity among the testing and developer community.
Jest Installation - All the prerequisites and set up steps needed to help you start Jest automation testing.
Using Jest with NodeJS Project - Learn how to leverage Jest framework to automate testing using a NodeJS Project.
Writing First Test for Jest Framework - Get started with code-based tutorial to help you write and execute your first Jest framework testing script.
Jest Vocabulary - Learn the industry renowned and official jargons of the Jest framework by digging deep into the Jest vocabulary.
Unit Testing with Jest - Step-by-step tutorial to help you execute unit testing with Jest framework.
Jest Basics - Learn about the most pivotal and basic features which makes Jest special.
Jest Parameterized Tests - Avoid code duplication and fasten automation testing with Jest using parameterized tests. Parameterization allows you to trigger the same test scenario over different test configurations by incorporating parameters.
Jest Matchers - Enforce assertions better with the help of matchers. Matchers help you compare the actual output with the expected one. Here is an example to see if the object is acquired from the correct class or not. -

|it('check_object_of_Car', () => { expect(newCar()).toBeInstanceOf(Car); });| | :- |

Jest Hooks: Setup and Teardown - Learn how to set up conditions which needs to be followed by the test execution and incorporate a tear down function to free resources after the execution is complete.
Jest Code Coverage - Unsure there is no code left unchecked in your application. Jest gives a specific flag called --coverage to help you generate code coverage.
HTML Report Generation - Learn how to create a comprehensive HTML report based on your Jest test execution.
Testing React app using Jest Framework - Learn how to test your react web-application with Jest framework in this detailed Jest tutorial.
Test using LambdaTest cloud Selenium Grid - Run your Jest testing script over LambdaTest cloud-based platform and leverage parallel testing to help trim down your test execution time.
Snapshot Testing for React Front Ends - Capture screenshots of your react based web-application and compare them automatically for visual anomalies with the help of Jest tutorial.
Bonus: Import ES modules with Jest - ES modules are also known as ECMAScript modules. Learn how to best use them by importing in your Jest testing scripts.
Jest vs Mocha vs Jasmine - Learn the key differences between the most popular JavaScript-based testing frameworks i.e. Jest, Mocha, and Jasmine.
Jest FAQs(Frequently Asked Questions) - Explore the most commonly asked questions around Jest framework, with their answers.