How to use takesDoneCallback method in Jest

Best JavaScript code snippet using jest

utils.js

Source:utils.js

...144});145const jestEachBuildDir = (0, _slash.default)(146  path.dirname(require.resolve('jest-each'))147);148function takesDoneCallback(fn) {149  return fn.length > 0;150}151function isGeneratorFunction(fn) {152  return (0, _isGeneratorFn.default)(fn);153}154const makeDescribe = (name, parent, mode) => {155  let _mode = mode;156  if (parent && !mode) {157    // If not set explicitly, inherit from the parent describe.158    _mode = parent.mode;159  }160  return {161    type: 'describeBlock',162    // eslint-disable-next-line sort-keys163    children: [],164    hooks: [],165    mode: _mode,166    name: (0, _jestUtil.convertDescriptorToString)(name),167    parent,168    tests: []169  };170};171exports.makeDescribe = makeDescribe;172const makeTest = (fn, mode, name, parent, timeout, asyncError) => ({173  type: 'test',174  // eslint-disable-next-line sort-keys175  asyncError,176  duration: null,177  errors: [],178  fn,179  invocations: 0,180  mode,181  name: (0, _jestUtil.convertDescriptorToString)(name),182  parent,183  seenDone: false,184  startedAt: null,185  status: null,186  timeout187}); // Traverse the tree of describe blocks and return true if at least one describe188// block has an enabled test.189exports.makeTest = makeTest;190const hasEnabledTest = describeBlock => {191  const {hasFocusedTests, testNamePattern} = (0, _state.getState)();192  return describeBlock.children.some(child =>193    child.type === 'describeBlock'194      ? hasEnabledTest(child)195      : !(196          child.mode === 'skip' ||197          (hasFocusedTests && child.mode !== 'only') ||198          (testNamePattern && !testNamePattern.test(getTestID(child)))199        )200  );201};202const getAllHooksForDescribe = describe => {203  const result = {204    afterAll: [],205    beforeAll: []206  };207  if (hasEnabledTest(describe)) {208    for (const hook of describe.hooks) {209      switch (hook.type) {210        case 'beforeAll':211          result.beforeAll.push(hook);212          break;213        case 'afterAll':214          result.afterAll.push(hook);215          break;216      }217    }218  }219  return result;220};221exports.getAllHooksForDescribe = getAllHooksForDescribe;222const getEachHooksForTest = test => {223  const result = {224    afterEach: [],225    beforeEach: []226  };227  let block = test.parent;228  do {229    const beforeEachForCurrentBlock = []; // TODO: inline after https://github.com/microsoft/TypeScript/pull/34840 is released230    let hook;231    for (hook of block.hooks) {232      switch (hook.type) {233        case 'beforeEach':234          beforeEachForCurrentBlock.push(hook);235          break;236        case 'afterEach':237          result.afterEach.push(hook);238          break;239      }240    } // 'beforeEach' hooks are executed from top to bottom, the opposite of the241    // way we traversed it.242    result.beforeEach = [...beforeEachForCurrentBlock, ...result.beforeEach];243  } while ((block = block.parent));244  return result;245};246exports.getEachHooksForTest = getEachHooksForTest;247const describeBlockHasTests = describe =>248  describe.children.some(249    child => child.type === 'test' || describeBlockHasTests(child)250  );251exports.describeBlockHasTests = describeBlockHasTests;252const _makeTimeoutMessage = (timeout, isHook) =>253  `Exceeded timeout of ${(0, _jestUtil.formatTime)(timeout)} for a ${254    isHook ? 'hook' : 'test'255  }.\nUse jest.setTimeout(newTimeout) to increase the timeout value, if this is a long-running test.`; // Global values can be overwritten by mocks or tests. We'll capture256// the original values in the variables before we require any files.257const {setTimeout, clearTimeout} = global;258function checkIsError(error) {259  return !!(error && error.message && error.stack);260}261const callAsyncCircusFn = (testOrHook, testContext, {isHook, timeout}) => {262  let timeoutID;263  let completed = false;264  const {fn, asyncError} = testOrHook;265  return new Promise((resolve, reject) => {266    timeoutID = setTimeout(267      () => reject(_makeTimeoutMessage(timeout, isHook)),268      timeout269    ); // If this fn accepts `done` callback we return a promise that fulfills as270    // soon as `done` called.271    if (takesDoneCallback(fn)) {272      let returnedValue = undefined;273      const done = reason => {274        // We need to keep a stack here before the promise tick275        const errorAtDone = new _jestUtil.ErrorWithStack(undefined, done);276        if (!completed && testOrHook.seenDone) {277          errorAtDone.message =278            'Expected done to be called once, but it was called multiple times.';279          if (reason) {280            errorAtDone.message +=281              ' Reason: ' +282              (0, _prettyFormat.format)(reason, {283                maxDepth: 3284              });285          }...

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