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How to use timerGame method in Jest

Best JavaScript code snippet using jest

index.test.js

Source:index.test.js

...52    expect(isUndefined(a)).toBeFalsy()53})54test('waits 10 second before ending the game', () => {55    jest.useFakeTimers()56    timerGame()57    timerGame()58    timerGame()59    timerGame()60    expect(setTimeout).toHaveBeenCalledTimes(4)61    expect(setTimeout).toHaveBeenLastCalledWith(expect.any(Function), 10000)62})63function timerGame(callback) {64    log('Ready....go!')65    setTimeout(() => {66        log('Times up -- stop!')67        callback && callback()68    }, 10000)69}70test('throttle', async () => {71    // jest.useFakeTimers();72    // Unable to setTimeout/Throttling on socket.73    // socket has its own default of 20000.74    // socketThrottling()75    // socketThrottling()76    // socketThrottling()77    // socketThrottling()...

timer.js

Source:timer.js

...5});6// mock a timer(not wait the timer and passing the waiting)7it.skip('should not wait 1s to run', () => {8  jest.useFakeTimers();9  timerGame();10  expect(setTimeout).toHaveBeenCalledTimes(1);11  expect(setTimeout).toHaveBeenCalledWith(expect.any(Function), 1000);12});13// reset timer to avoid interference between them14describe.skip('reset all timer of they used more than one time', () => {15  // reset timer mocking16  beforeEach(() => {17    jest.useFakeTimers();18  })19  it('should not wait 1s to run', () => {20    timerGame();21    expect(setTimeout).toHaveBeenCalledTimes(1);22    expect(setTimeout).toHaveBeenCalledWith(expect.any(Function), 1000);23  });24  it('should passed', () => {25    // jest.useFakeTimers();26    timerGame();27    expect(setTimeout).toHaveBeenCalledTimes(1);28    expect(setTimeout).toHaveBeenCalledWith(expect.any(Function), 1000);29  });30  31});32// fast-forward all timers to asserts that all callback runs33test.skip('should call callback after 1s', () => {34  const cb = jest.fn();35  timerGame(cb);36  // at this time cb not called yet (<1s)37  expect(cb).not.toBeCalled();38  // fast forward all timers39  jest.runAllTimers();40  expect(cb).toBeCalled();41  expect(cb).toHaveBeenCalledTimes(1);42});43// like this above but with advanceTimersByTime API44test('should call callback after 1s using advanceTimersByTime API', () => {45  const cb = jest.fn();46  timerGame(cb);47  // at this time cb not called yet (<1s)48  expect(cb).not.toBeCalled();49  // fast forward all timers50  jest.advanceTimersByTime(1000);51  expect(cb).toBeCalled();52  expect(cb).toHaveBeenCalledTimes(1);53});54// fast-forward timer who creating other timer and catch the current timer55describe.skip('infiniteTimerGame', () => {56  test.skip('should schedule a 10s timer after 1s', () => {57    58    const cb = jest.fn();59    infiniteTimerGame(cb);60    // at this time settimeout have been called...

timer_game.test.js

Source:timer_game.test.js

...4		jest.spyOn(global, 'setTimeout');5	});6	it('waits 1 second before ending the game', () => {7		const timerGame = require('../timerGame');8		timerGame();9		expect(setTimeout).toBeCalledTimes(1);10		expect(setTimeout).toBeCalledWith(expect.any(Function), 1000);11	});12	it('calls the callback after 1 second via runAllTimers', () => {13		const timerGame = require('../timerGame');14		const callback = jest.fn();15		timerGame(callback);16		// At this point in time, the callback should not have been called yet17		expect(callback).not.toBeCalled();18		// Fast-forward until all timers have been executed19		jest.runAllTimers();20		// Now our callback should have been called!21		expect(callback).toBeCalled();22		expect(callback).toBeCalledTimes(1);23	});24	it('calls the callback after 1 second via advanceTimersByTime', () => {25		const timerGame = require('../timerGame');26		const callback = jest.fn();27		timerGame(callback);28		// At this point in time, the callback should not have been called yet29		expect(callback).not.toBeCalled();30		// Fast-forward until all timers have been executed31		jest.advanceTimersByTime(1000);32		// Now our callback should have been called!33		expect(callback).toBeCalled();34		expect(callback).toBeCalledTimes(1);35	});...

timerGame.test.js

Source:timerGame.test.js

1'use strict';2jest.useFakeTimers()3test('waits one second before ending the game', () => {4    const timerGame = require('../src/timerGame')5    timerGame()6    expect(setTimeout).toHaveBeenCalledTimes(1)7    expect(setTimeout).toHaveBeenLastCalledWith(expect.any(Function), 1000)8})9test('calls the callback after one second', () => {10    const timerGame = require('../src/timerGame')11    const callback = jest.fn()12    timerGame(callback)13    //At this point in time, the callback should not have been called yet14    expect(callback).not.toBeCalled()15    //Fast-forward until all timers have been executed16    jest.runAllTimers()17    //Now our callback should have been called!18    expect(callback).toBeCalled()19    expect(callback).toHaveBeenCalledTimes(1)20})21it('calls the callback after one second via advanceTimersByTime', () => {22    const timerGame = require('../src/timerGame')23    const callback = jest.fn()24    timerGame(callback)25    //At this point in time, the callback should not have been called yet26    expect(callback).not.toBeCalled()27    //Fast-forward until all timers have been executed28    jest.advanceTimersByTime(1000)29    //Now our callback should have been called!30    expect(callback).toBeCalled()31    expect(callback).toHaveBeenCalledTimes(1)...

Part-10-Timer Mocks.spec.js

Source:Part-10-Timer Mocks.spec.js

1// __tests__/timerGame-test.js2jest.useFakeTimers();3test("waits 1 second before ending the game", () => {4  const timerGame = require("./timerGame");5  timerGame();6  expect(setTimeout).toHaveBeenCalledTimes(1);7  expect(setTimeout).toHaveBeenLastCalledWith(expect.any(Function), 1000);8});9test("calls the callback after 1 second", () => {10  const timerGame = require("./timerGame");11  const callback = jest.fn();12  timerGame(callback);13  // At this point in time, the callback should not have been called yet14  expect(callback).not.toBeCalled();15  // Fast-forward until all timers have been executed16  jest.runAllTimers();17  // Now our callback should have been called!18  expect(callback).toBeCalled();19  expect(callback).toHaveBeenCalledTimes(1);20});21it("calls the callback after 1 second via advanceTimersByTime", () => {22  const timerGame = require("./timerGame");23  const callback = jest.fn();24  timerGame(callback);25  // At this point in time, the callback should not have been called yet26  expect(callback).not.toBeCalled();27  // Fast-forward until all timers have been executed28  jest.advanceTimersByTime(1000);29  // Now our callback should have been called!30  expect(callback).toBeCalled();31  expect(callback).toHaveBeenCalledTimes(1);...

timerGame-test.js

Source:timerGame-test.js

1jest.dontMock('../timerGame');2describe('timerGame', function() {3  it('waits 1 second before ending the game', function() {4    var timerGame = require('../timerGame');5    timerGame();6    expect(setTimeout.mock.calls.length).toBe(1);7    expect(setTimeout.mock.calls[0][1]).toBe(1000);8  });9  it('calls the callback after 1 second', function() {10    var timerGame = require('../timerGame');11    var callback = jest.genMockFunction();12    timerGame(callback);13    // At this point in time, the callback should not have been called yet14    expect(callback).not.toBeCalled();15    // Fast-forward until all timers have been executed16    jest.runAllTimers();17    // Now our callback should have been called!18    expect(callback).toBeCalled()19    expect(callback.mock.calls.length).toBe(1);20  });...

timerGame.spec.js

Source:timerGame.spec.js

1'use strict';2jest.useFakeTimers();3test('waits 1 second before ending the game', () => {4  const timerGame = require('./timerGame');5  timerGame(null, 1000);6  expect(setTimeout).toHaveBeenCalledTimes(1);7  expect(setTimeout).toHaveBeenLastCalledWith(expect.any(Function), 1000);8});9test('calls the callback after 1 second', () => {10    const timerGame = require('./timerGame');11    const callback = jest.fn();12  13    timerGame(callback);14  15    // At this point in time, the callback should not have been called yet16    expect(callback).not.toBeCalled();17  18    // Fast-forward until all timers have been executed19    jest.runAllTimers();20  21    // Now our callback should have been called!22    expect(callback).toBeCalled();23    expect(callback).toHaveBeenCalledTimes(1);...

timerGame.js

Source:timerGame.js

1// timerGame.js2'use strict';3function timerGame(callback, timeout) {4  timeout = timeout || 50005  console.log('Ready....go!');6  setTimeout(() => {7    console.log('Times up -- stop!');8    callback && callback();9  }, timeout);10}...

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