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How to use workerReplyCustomMessage method in Jest

Best JavaScript code snippet using jest

Farm.test.js

Source:Farm.test.js

...17function workerReply(i, error, result) {18  workerReplyStart(i);19  workerReplyEnd(i, error, result);20}21function workerReplyCustomMessage(i, message) {22  mockWorkerCalls[i].onCustomMessage(message);23}24describe('Farm', () => {25  beforeEach(() => {26    mockWorkerCalls = [];27    callback = elric.fn((...args) => {28      mockWorkerCalls.push({29        onCustomMessage: args[4],30        onEnd: args[3],31        onStart: args[2],32        passed: args[1],33        workerId: args[0],34      });35    });36  });37  it('sends a request to one worker', () => {38    const farm = new Farm(4, callback);39    farm.doWork('foo', 42);40    expect(callback).toHaveBeenCalledTimes(1);41    expect(callback).toHaveBeenCalledWith(42      0,43      [1, true, 'foo', [42]],44      expect.any(Function),45      expect.any(Function),46      expect.any(Function),47    );48  });49  it('sends four requests to four unique workers', () => {50    const farm = new Farm(4, callback);51    farm.doWork('foo', 42);52    farm.doWork('foo1', 43);53    farm.doWork('foo2', 44);54    farm.doWork('foo3', 45);55    expect(callback).toHaveBeenCalledTimes(4);56    expect(callback).toHaveBeenNthCalledWith(57      1,58      0, // first worker59      [1, true, 'foo', [42]],60      expect.any(Function),61      expect.any(Function),62      expect.any(Function),63    );64    expect(callback).toHaveBeenNthCalledWith(65      2,66      1, // second worker67      [1, true, 'foo1', [43]],68      expect.any(Function),69      expect.any(Function),70      expect.any(Function),71    );72    expect(callback).toHaveBeenNthCalledWith(73      3,74      2, // third worker75      [1, true, 'foo2', [44]],76      expect.any(Function),77      expect.any(Function),78      expect.any(Function),79    );80    expect(callback).toHaveBeenNthCalledWith(81      4,82      3, // fourth worker83      [1, true, 'foo3', [45]],84      expect.any(Function),85      expect.any(Function),86      expect.any(Function),87    );88  });89  it('handles null computeWorkerKey, sending to first worker', async () => {90    const computeWorkerKey = elric.fn(() => null);91    const farm = new Farm(4, callback, {computeWorkerKey});92    const p0 = farm.doWork('foo', 42);93    workerReply(0);94    await p0;95    expect(computeWorkerKey).toBeCalledTimes(1);96    expect(computeWorkerKey).toHaveBeenNthCalledWith(1, 'foo', 42);97    expect(callback).toHaveBeenCalledTimes(1);98    expect(callback).toHaveBeenNthCalledWith(99      1,100      0, // first worker101      [1, true, 'foo', [42]],102      expect.any(Function),103      expect.any(Function),104      expect.any(Function),105    );106  });107  it('sends the same worker key to the same worker', async () => {108    const computeWorkerKey = elric109      .fn(() => {})110      .mockReturnValueOnce('one')111      .mockReturnValueOnce('two')112      .mockReturnValueOnce('one');113    const farm = new Farm(4, callback, {computeWorkerKey});114    const p0 = farm.doWork('foo', 42);115    workerReply(0);116    await p0;117    const p1 = farm.doWork('foo1', 43);118    workerReply(1);119    await p1;120    const p2 = farm.doWork('foo2', 44);121    workerReply(2);122    await p2;123    expect(computeWorkerKey).toBeCalledTimes(3);124    expect(computeWorkerKey).toHaveBeenNthCalledWith(1, 'foo', 42);125    expect(computeWorkerKey).toHaveBeenNthCalledWith(2, 'foo1', 43);126    expect(computeWorkerKey).toHaveBeenNthCalledWith(3, 'foo2', 44);127    expect(callback).toHaveBeenCalledTimes(3);128    expect(callback).toHaveBeenNthCalledWith(129      1,130      0, // first worker131      [1, true, 'foo', [42]],132      expect.any(Function),133      expect.any(Function),134      expect.any(Function),135    );136    expect(callback).toHaveBeenNthCalledWith(137      2,138      1, // second worker139      [1, true, 'foo1', [43]],140      expect.any(Function),141      expect.any(Function),142      expect.any(Function),143    );144    expect(callback).toHaveBeenNthCalledWith(145      3,146      0, // first worker again147      [1, true, 'foo2', [44]],148      expect.any(Function),149      expect.any(Function),150      expect.any(Function),151    );152  });153  it('returns the result if the call worked', async () => {154    const farm = new Farm(4, callback);155    const promise = farm.doWork('car', 'plane');156    workerReply(0, null, 34);157    const result = await promise;158    expect(result).toEqual(34);159  });160  it('throws if the call failed', async () => {161    const farm = new Farm(4, callback);162    const promise = farm.doWork('car', 'plane');163    let error = null;164    workerReply(0, new TypeError('Massively broken'));165    try {166      await promise;167    } catch (err) {168      error = err;169    }170    expect(error).not.toBe(null);171    expect(error).toBeInstanceOf(TypeError);172  });173  it('checks that once a sticked task finishes, next time is sent to that worker', async () => {174    const farm = new Farm(4, callback, {175      computeWorkerKey: () => '1234567890abcdef',176    });177    // Worker 1 successfully replies with "17" as a result.178    const p0 = farm.doWork('car', 'plane');179    workerReply(0, null, 17);180    await p0;181    // Note that the stickiness is not created by the method name or the182    // arguments it is solely controlled by the provided "computeWorkerKey"183    // method, which in the test example always returns the same key, so all184    // calls should be redirected to worker 1 (which is the one that resolved185    // the first call).186    const p1 = farm.doWork('foo', 'bar');187    workerReply(1, null, 17);188    await p1;189    // The first time, a call with a "1234567890abcdef" hash had never been190    // done earlier ("foo" call), so it got queued to all workers. Later, since191    // the one that resolved the call was the one in position 1, all subsequent192    // calls are only redirected to that worker.193    expect(callback).toHaveBeenCalledTimes(2); // Only "foo".194    expect(callback).toHaveBeenNthCalledWith(195      1,196      0, // first worker197      [1, true, 'car', ['plane']],198      expect.any(Function),199      expect.any(Function),200      expect.any(Function),201    );202    expect(callback).toHaveBeenNthCalledWith(203      2,204      0, // first worker205      [1, true, 'foo', ['bar']],206      expect.any(Function),207      expect.any(Function),208      expect.any(Function),209    );210  });211  it('checks that even before a sticked task finishes, next time is sent to that worker', async () => {212    const farm = new Farm(4, callback, {213      computeWorkerKey: () => '1234567890abcdef',214    });215    // Note that the worker is sending a start response synchronously.216    const p0 = farm.doWork('car', 'plane');217    workerReplyStart(0);218    // Note that the worker is sending a start response synchronously.219    const p1 = farm.doWork('foo', 'bar');220    // The first call is sent the worker, the second is queued221    expect(callback).toHaveBeenCalledTimes(1);222    // Flush the queue223    workerReplyEnd(0, null, 17);224    await p0;225    workerReply(1, null, 17);226    await p1;227    // Both requests are send to the same worker.  The first time, a call with228    // a "1234567890abcdef" hash had never been done earlier ("foo" call), so229    // it got queued to all workers. Later, since the one that resolved the230    // call was the one in position 1, all subsequent calls are only redirected231    // to that worker.232    expect(callback).toHaveBeenCalledTimes(2);233    expect(callback).toHaveBeenNthCalledWith(234      1,235      0, // first worker236      [1, true, 'car', ['plane']],237      expect.any(Function),238      expect.any(Function),239      expect.any(Function),240    );241    expect(callback).toHaveBeenNthCalledWith(242      2,243      0, // first worker244      [1, true, 'foo', ['bar']],245      expect.any(Function),246      expect.any(Function),247      expect.any(Function),248    );249  });250  it('checks that locking works, and jobs are never lost', async () => {251    const hash = elric252      .fn()253      // This will go to both queues, but picked by the first worker.254      .mockReturnValueOnce(0)255      // This will go to both queues too, but picked by the second worker.256      .mockReturnValueOnce(1)257      // This will go to worker 0, now only assigned to it.258      .mockReturnValueOnce(0)259      // This will go to worker 1, now only assigned to it.260      .mockReturnValueOnce(1)261      // This will go to both queues too, but will wait, since workers are busy.262      .mockReturnValueOnce(2)263      // This will only go to the first queue.264      .mockReturnValueOnce(0)265      // This will be gone if the queue implementation is wrong.266      .mockReturnValueOnce(0)267      // Push onto the second queue; potentially wiping the earlier job.268      .mockReturnValueOnce(1);269    const farm = new Farm(2, callback, {computeWorkerKey: hash});270    // First and second jobs get resolved, so that their hash is sticked to271    // the right worker: worker assignment is performed when workers reply, not272    // when the call is made.273    const p0 = farm.doWork('work-0');274    const p1 = farm.doWork('work-1');275    workerReply(0, null, 'response-0');276    await p0;277    workerReply(1, null, 'response-1');278    await p1;279    // Now we perform the rest of the calls (7 resolves before 5 and 6, since 4280    // is in both queues, and as soon as you resolve 4, 7 will be picked).281    const p2 = farm.doWork('work-2');282    const p3 = farm.doWork('work-3');283    const p4 = farm.doWork('work-4');284    const p5 = farm.doWork('work-5');285    const p6 = farm.doWork('work-6');286    const p7 = farm.doWork('work-7');287    workerReply(2, null, 'response-2');288    await p2;289    workerReply(3, null, 'response-3');290    await p3;291    workerReply(4, null, 'response-4');292    await p4;293    workerReply(5, null, 'response-7');294    await p7;295    workerReply(6, null, 'response-5');296    await p5;297    workerReply(7, null, 'response-6');298    await p6;299    await expect(p0).resolves.toBe('response-0');300    await expect(p1).resolves.toBe('response-1');301    await expect(p2).resolves.toBe('response-2');302    await expect(p3).resolves.toBe('response-3');303    await expect(p4).resolves.toBe('response-4');304    await expect(p5).resolves.toBe('response-5');305    await expect(p6).resolves.toBe('response-6');306    await expect(p7).resolves.toBe('response-7');307  });308  it('can receive custom messages from workers', async () => {309    expect.assertions(2);310    const farm = new Farm(2, callback);311    const p0 = farm.doWork('work-0');312    const p1 = farm.doWork('work-1');313    const unsubscribe = p0.UNSTABLE_onCustomMessage(message => {314      expect(message).toEqual({key: 0, message: 'foo'});315    });316    p1.UNSTABLE_onCustomMessage(message => {317      expect(message).toEqual({key: 1, message: 'bar'});318    });319    workerReplyStart(0);320    workerReplyStart(1);321    workerReplyCustomMessage(0, {key: 0, message: 'foo'});322    workerReplyCustomMessage(1, {key: 1, message: 'bar'});323    unsubscribe();324    // This message will not received because the listener already325    // unsubscribed.326    workerReplyCustomMessage(0, {key: 0, message: 'baz'});327    workerReply(0, null, 17);328    workerReply(1, null, 17);329    await p0;330    await p1;331  });...

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