How to use workerReplyEnd method in Jest

Best JavaScript code snippet using jest

index.test.js

Source:index.test.js

...10let mockWorkers;11function workerReplyStart(i) {12  mockWorkers[i].send.mock.calls[0][1](mockWorkers[i]);13}14function workerReplyEnd(i, error, result) {15  mockWorkers[i].send.mock.calls[0][2](error, result);16}17function workerReply(i, error, result) {18  workerReplyStart(i);19  workerReplyEnd(i, error, result);20}21beforeEach(() => {22  mockWorkers = [];23  // The worker mock returns a worker with custom methods, plus it stores them24  // in a global list, so that they can be accessed later. This list is reset in25  // every test.26  jest.mock('../Worker', () => {27    const fakeClass = jest.fn(() => {28      const fakeWorker = {29        getStderr: () => ({once() {}, pipe() {}}),30        getStdout: () => ({once() {}, pipe() {}}),31        send: jest.fn(),32      };33      mockWorkers.push(fakeWorker);...

71index.test.js

Source:71index.test.js

...10let mockWorkers;11function workerReplyStart(i) {12  mockWorkers[i].send.mock.calls[0][1](mockWorkers[i]);13}14function workerReplyEnd(i, error, result) {15  mockWorkers[i].send.mock.calls[0][2](error, result);16}17function workerReply(i, error, result) {18  workerReplyStart(i);19  workerReplyEnd(i, error, result);20}21beforeEach(() => {22  mockWorkers = [];23  // The worker mock returns a worker with custom methods, plus it stores them24  // in a global list, so that they can be accessed later. This list is reset in25  // every test.26  jest.mock('../Worker', () => {27    const fakeClass = jest.fn(() => {28      const fakeWorker = {29        getStderr: () => ({once() {}, pipe() {}}),30        getStdout: () => ({once() {}, pipe() {}}),31        send: jest.fn(),32      };33      mockWorkers.push(fakeWorker);...

Farm.test.js

Source:Farm.test.js

...10let callback;11function workerReplyStart(i) {12  mockWorkerCalls[i].onStart({getWorkerId: () => mockWorkerCalls[i].workerId});13}14function workerReplyEnd(i, error, result) {15  mockWorkerCalls[i].onEnd(error, result);16}17function workerReply(i, error, result) {18  workerReplyStart(i);19  workerReplyEnd(i, error, result);20}21describe('Farm', () => {22  beforeEach(() => {23    mockWorkerCalls = [];24    callback = jest.fn((...args) => {25      mockWorkerCalls.push({26        onEnd: args[3],27        onStart: args[2],28        passed: args[1],29        workerId: args[0],30      });31    });32  });33  it('sends a request to one worker', () => {34    const farm = new Farm(4, callback);35    farm.doWork('foo', 42);36    expect(callback).toHaveBeenCalledTimes(1);37    expect(callback).toHaveBeenCalledWith(38      0,39      [1, true, 'foo', [42]],40      expect.any(Function),41      expect.any(Function),42    );43  });44  it('sends four requests to four unique workers', () => {45    const farm = new Farm(4, callback);46    farm.doWork('foo', 42);47    farm.doWork('foo1', 43);48    farm.doWork('foo2', 44);49    farm.doWork('foo3', 45);50    expect(callback).toHaveBeenCalledTimes(4);51    expect(callback).toHaveBeenNthCalledWith(52      1,53      0, // first worker54      [1, true, 'foo', [42]],55      expect.any(Function),56      expect.any(Function),57    );58    expect(callback).toHaveBeenNthCalledWith(59      2,60      1, // second worker61      [1, true, 'foo1', [43]],62      expect.any(Function),63      expect.any(Function),64    );65    expect(callback).toHaveBeenNthCalledWith(66      3,67      2, // third worker68      [1, true, 'foo2', [44]],69      expect.any(Function),70      expect.any(Function),71    );72    expect(callback).toHaveBeenNthCalledWith(73      4,74      3, // fourth worker75      [1, true, 'foo3', [45]],76      expect.any(Function),77      expect.any(Function),78    );79  });80  it('handles null computeWorkerKey, sending to first worker', async () => {81    const computeWorkerKey = jest.fn(() => null);82    const farm = new Farm(4, callback, computeWorkerKey);83    const p0 = farm.doWork('foo', 42);84    workerReply(0);85    await p0;86    expect(computeWorkerKey).toBeCalledTimes(1);87    expect(computeWorkerKey).toHaveBeenNthCalledWith(1, 'foo', 42);88    expect(callback).toHaveBeenCalledTimes(1);89    expect(callback).toHaveBeenNthCalledWith(90      1,91      0, // first worker92      [1, true, 'foo', [42]],93      expect.any(Function),94      expect.any(Function),95    );96  });97  it('sends the same worker key to the same worker', async () => {98    const computeWorkerKey = jest99      .fn(() => {})100      .mockReturnValueOnce('one')101      .mockReturnValueOnce('two')102      .mockReturnValueOnce('one');103    const farm = new Farm(4, callback, computeWorkerKey);104    const p0 = farm.doWork('foo', 42);105    workerReply(0);106    await p0;107    const p1 = farm.doWork('foo1', 43);108    workerReply(1);109    await p1;110    const p2 = farm.doWork('foo2', 44);111    workerReply(2);112    await p2;113    expect(computeWorkerKey).toBeCalledTimes(3);114    expect(computeWorkerKey).toHaveBeenNthCalledWith(1, 'foo', 42);115    expect(computeWorkerKey).toHaveBeenNthCalledWith(2, 'foo1', 43);116    expect(computeWorkerKey).toHaveBeenNthCalledWith(3, 'foo2', 44);117    expect(callback).toHaveBeenCalledTimes(3);118    expect(callback).toHaveBeenNthCalledWith(119      1,120      0, // first worker121      [1, true, 'foo', [42]],122      expect.any(Function),123      expect.any(Function),124    );125    expect(callback).toHaveBeenNthCalledWith(126      2,127      1, // second worker128      [1, true, 'foo1', [43]],129      expect.any(Function),130      expect.any(Function),131    );132    expect(callback).toHaveBeenNthCalledWith(133      3,134      0, // first worker again135      [1, true, 'foo2', [44]],136      expect.any(Function),137      expect.any(Function),138    );139  });140  it('returns the result if the call worked', async () => {141    const farm = new Farm(4, callback);142    const promise = farm.doWork('car', 'plane');143    workerReply(0, null, 34);144    const result = await promise;145    expect(result).toEqual(34);146  });147  it('throws if the call failed', async () => {148    const farm = new Farm(4, callback);149    const promise = farm.doWork('car', 'plane');150    let error = null;151    workerReply(0, new TypeError('Massively broken'));152    try {153      await promise;154    } catch (err) {155      error = err;156    }157    expect(error).not.toBe(null);158    expect(error).toBeInstanceOf(TypeError);159  });160  it('checks that once a sticked task finishes, next time is sent to that worker', async () => {161    const farm = new Farm(4, callback, () => '1234567890abcdef');162    // Worker 1 successfully replies with "17" as a result.163    const p0 = farm.doWork('car', 'plane');164    workerReply(0, null, 17);165    await p0;166    // Note that the stickiness is not created by the method name or the arguments167    // it is solely controlled by the provided "computeWorkerKey" method, which in168    // the test example always returns the same key, so all calls should be169    // redirected to worker 1 (which is the one that resolved the first call).170    const p1 = farm.doWork('foo', 'bar');171    workerReply(1, null, 17);172    await p1;173    // The first time, a call with a "1234567890abcdef" hash had never been done174    // earlier ("foo" call), so it got queued to all workers. Later, since the one175    // that resolved the call was the one in position 1, all subsequent calls are176    // only redirected to that worker.177    expect(callback).toHaveBeenCalledTimes(2); // Only "foo".178    expect(callback).toHaveBeenNthCalledWith(179      1,180      0, // first worker181      [1, true, 'car', ['plane']],182      expect.any(Function),183      expect.any(Function),184    );185    expect(callback).toHaveBeenNthCalledWith(186      2,187      0, // first worker188      [1, true, 'foo', ['bar']],189      expect.any(Function),190      expect.any(Function),191    );192  });193  it('checks that even before a sticked task finishes, next time is sent to that worker', async () => {194    const farm = new Farm(4, callback, () => '1234567890abcdef');195    // Note that the worker is sending a start response synchronously.196    const p0 = farm.doWork('car', 'plane');197    workerReplyStart(0);198    // Note that the worker is sending a start response synchronously.199    const p1 = farm.doWork('foo', 'bar');200    // The first call is sent the worker, the second is queued201    expect(callback).toHaveBeenCalledTimes(1);202    // Flush the queue203    workerReplyEnd(0, null, 17);204    await p0;205    workerReply(1, null, 17);206    await p1;207    // Both requests are send to the same worker208    // The first time, a call with a "1234567890abcdef" hash had never been done209    // earlier ("foo" call), so it got queued to all workers. Later, since the one210    // that resolved the call was the one in position 1, all subsequent calls are211    // only redirected to that worker.212    expect(callback).toHaveBeenCalledTimes(2);213    expect(callback).toHaveBeenNthCalledWith(214      1,215      0, // first worker216      [1, true, 'car', ['plane']],217      expect.any(Function),...

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