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How to use assertCallsToChild method in Jest

Best JavaScript code snippet using jest

thread-integration.test.js

Source:thread-integration.test.js

...16}17function replySuccess(i, result) {18  mockForkedProcesses[i].emit('message', [PARENT_MESSAGE_OK, result]);19}20function assertCallsToChild(childNum, ...calls) {21  expect(mockForkedProcesses[childNum].postMessage).toHaveBeenCalledTimes(22    calls.length + 1,23  );24  calls.forEach(([methodName, ...args], numCall) => {25    expect(26      mockForkedProcesses[childNum].postMessage.mock.calls[numCall + 1][0],27    ).toEqual([CHILD_MESSAGE_CALL, true, methodName, args]);28  });29}30describe('Jest Worker Process Integration', () => {31  beforeEach(() => {32    mockForkedProcesses = [];33    jest.mock('worker_threads', () => {34      const fakeClass = jest.fn(() => {35        const forkedProcess = mockBuildForkedProcess();36        mockForkedProcesses.push(forkedProcess);37        return forkedProcess;38      });39      return {40        Worker: fakeClass,41        __esModule: true,42      };43    });44    Farm = require('../index').Worker;45  });46  afterEach(() => {47    jest.resetModules();48  });49  it('calls a single method from the worker', async () => {50    const farm = new Farm('/tmp/baz.js', {51      enableWorkerThreads: true,52      exposedMethods: ['foo', 'bar'],53      numWorkers: 4,54    });55    const promise = farm.foo();56    replySuccess(0, 42);57    expect(await promise).toBe(42);58  });59  it('distributes sequential calls across child processes', async () => {60    const farm = new Farm('/tmp/baz.js', {61      enableWorkerThreads: true,62      exposedMethods: ['foo', 'bar'],63      numWorkers: 4,64    });65    // The first call will go to the first child process.66    const promise0 = farm.foo('param-0');67    assertCallsToChild(0, ['foo', 'param-0']);68    replySuccess(0, 'worker-0');69    expect(await promise0).toBe('worker-0');70    // The second call will go to the second child process.71    const promise1 = farm.foo(1);72    assertCallsToChild(1, ['foo', 1]);73    replySuccess(1, 'worker-1');74    expect(await promise1).toBe('worker-1');75  });76  it('schedules the task on the first available child processes if the scheduling policy is in-order', async () => {77    const farm = new Farm('/tmp/baz.js', {78      enableWorkerThreads: true,79      exposedMethods: ['foo', 'bar'],80      numWorkers: 4,81      workerSchedulingPolicy: 'in-order',82    });83    // The first call will go to the first child process.84    const promise0 = farm.foo('param-0');85    assertCallsToChild(0, ['foo', 'param-0']);86    // The second call will go to the second child process.87    const promise1 = farm.foo(1);88    // The first task on worker 0 completes89    replySuccess(0, 'worker-0');90    expect(await promise0).toBe('worker-0');91    // The second task on worker 1 completes92    assertCallsToChild(1, ['foo', 1]);93    replySuccess(1, 'worker-1');94    expect(await promise1).toBe('worker-1');95    // The third call will go to the first child process96    const promise2 = farm.foo('param-2');97    assertCallsToChild(0, ['foo', 'param-0'], ['foo', 'param-2']);98    replySuccess(0, 'worker-0');99    expect(await promise2).toBe('worker-0');100  });101  it('schedules the task on the first available child processes', async () => {102    const farm = new Farm('/tmp/baz.js', {103      enableWorkerThreads: true,104      exposedMethods: ['foo', 'bar'],105      numWorkers: 4,106    });107    // The first call will go to the first child process.108    const promise0 = farm.foo('param-0');109    assertCallsToChild(0, ['foo', 'param-0']);110    replySuccess(0, 'worker-0');111    expect(await promise0).toBe('worker-0');112    // The second call will go to the second child process.113    const promise1 = farm.foo(1);114    assertCallsToChild(1, ['foo', 1]);115    replySuccess(1, 'worker-1');116    expect(await promise1).toBe('worker-1');117  });118  it('distributes concurrent calls across child processes', async () => {119    const farm = new Farm('/tmp/baz.js', {120      enableWorkerThreads: true,121      exposedMethods: ['foo', 'bar'],122      numWorkers: 4,123    });124    // Do 3 calls to the farm in parallel.125    const promise0 = farm.foo('param-0');126    const promise1 = farm.foo('param-1');127    const promise2 = farm.foo('param-2');128    // Check that the method calls are sent to each separate child process.129    assertCallsToChild(0, ['foo', 'param-0']);130    assertCallsToChild(1, ['foo', 'param-1']);131    assertCallsToChild(2, ['foo', 'param-2']);132    // Send different responses from each child.133    replySuccess(0, 'worker-0');134    replySuccess(1, 'worker-1');135    replySuccess(2, 'worker-2');136    // Check137    expect(await promise0).toBe('worker-0');138    expect(await promise1).toBe('worker-1');139    expect(await promise2).toBe('worker-2');140  });141  it('sticks parallel calls to children', async () => {142    const farm = new Farm('/tmp/baz.js', {143      computeWorkerKey: () => '1234567890abcdef',144      enableWorkerThreads: true,145      exposedMethods: ['foo', 'bar'],146      numWorkers: 4,147    });148    // Do 3 calls to the farm in parallel.149    const promise0 = farm.foo('param-0');150    const promise1 = farm.foo('param-1');151    const promise2 = farm.foo('param-2');152    // Send different responses for each call (from the same child).153    replySuccess(0, 'worker-0');154    replySuccess(0, 'worker-1');155    replySuccess(0, 'worker-2');156    // Check that all the calls have been received by the same child).157    assertCallsToChild(158      0,159      ['foo', 'param-0'],160      ['foo', 'param-1'],161      ['foo', 'param-2'],162    );163    // Check that responses are correct.164    expect(await promise0).toBe('worker-0');165    expect(await promise1).toBe('worker-1');166    expect(await promise2).toBe('worker-2');167  });...

process-integration.test.js

Source:process-integration.test.js

...16}17function replySuccess(i, result) {18  mockForkedProcesses[i].emit('message', [PARENT_MESSAGE_OK, result]);19}20function assertCallsToChild(childNum, ...calls) {21  expect(mockForkedProcesses[childNum].send).toHaveBeenCalledTimes(22    calls.length + 1,23  );24  calls.forEach(([methodName, ...args], numCall) => {25    expect(26      mockForkedProcesses[childNum].send.mock.calls[numCall + 1][0],27    ).toEqual([CHILD_MESSAGE_CALL, true, methodName, args]);28  });29}30jest.mock('worker_threads', () => {31  throw Error('Unsupported');32});33describe('Jest Worker Integration', () => {34  beforeEach(() => {35    mockForkedProcesses = [];36    jest.mock('child_process', () => ({37      fork() {38        const forkedProcess = mockBuildForkedProcess();39        mockForkedProcesses.push(forkedProcess);40        return forkedProcess;41      },42    }));43    Farm = require('../index').Worker;44  });45  afterEach(() => {46    jest.resetModules();47  });48  it('calls a single method from the worker', async () => {49    const farm = new Farm('/tmp/baz.js', {50      exposedMethods: ['foo', 'bar'],51      numWorkers: 4,52    });53    const promise = farm.foo();54    replySuccess(0, 42);55    expect(await promise).toBe(42);56  });57  it('distributes sequential calls across child processes', async () => {58    const farm = new Farm('/tmp/baz.js', {59      exposedMethods: ['foo', 'bar'],60      numWorkers: 4,61    });62    // The first call will go to the first child process.63    const promise0 = farm.foo('param-0');64    assertCallsToChild(0, ['foo', 'param-0']);65    replySuccess(0, 'worker-0');66    expect(await promise0).toBe('worker-0');67    // The second call will go to the second child process.68    const promise1 = farm.foo(1);69    assertCallsToChild(1, ['foo', 1]);70    replySuccess(1, 'worker-1');71    expect(await promise1).toBe('worker-1');72  });73  it('schedules the task on the first available child processes if the scheduling policy is in-order', async () => {74    const farm = new Farm('/tmp/baz.js', {75      exposedMethods: ['foo', 'bar'],76      numWorkers: 4,77      workerSchedulingPolicy: 'in-order',78    });79    // The first call will go to the first child process.80    const promise0 = farm.foo('param-0');81    assertCallsToChild(0, ['foo', 'param-0']);82    // The second call will go to the second child process.83    const promise1 = farm.foo(1);84    // The first task on worker 0 completes85    replySuccess(0, 'worker-0');86    expect(await promise0).toBe('worker-0');87    // The second task on worker 1 completes88    assertCallsToChild(1, ['foo', 1]);89    replySuccess(1, 'worker-1');90    expect(await promise1).toBe('worker-1');91    // The third call will go to the first child process92    const promise2 = farm.foo('param-2');93    assertCallsToChild(0, ['foo', 'param-0'], ['foo', 'param-2']);94    replySuccess(0, 'worker-0');95    expect(await promise2).toBe('worker-0');96  });97  it('distributes concurrent calls across child processes', async () => {98    const farm = new Farm('/tmp/baz.js', {99      exposedMethods: ['foo', 'bar'],100      numWorkers: 4,101    });102    // Do 3 calls to the farm in parallel.103    const promise0 = farm.foo('param-0');104    const promise1 = farm.foo('param-1');105    const promise2 = farm.foo('param-2');106    // Check that the method calls are sent to each separate child process.107    assertCallsToChild(0, ['foo', 'param-0']);108    assertCallsToChild(1, ['foo', 'param-1']);109    assertCallsToChild(2, ['foo', 'param-2']);110    // Send different responses from each child.111    replySuccess(0, 'worker-0');112    replySuccess(1, 'worker-1');113    replySuccess(2, 'worker-2');114    // Check115    expect(await promise0).toBe('worker-0');116    expect(await promise1).toBe('worker-1');117    expect(await promise2).toBe('worker-2');118  });119  it('sticks parallel calls to children', async () => {120    const farm = new Farm('/tmp/baz.js', {121      computeWorkerKey: () => '1234567890abcdef',122      exposedMethods: ['foo', 'bar'],123      numWorkers: 4,124    });125    // Do 3 calls to the farm in parallel.126    const promise0 = farm.foo('param-0');127    const promise1 = farm.foo('param-1');128    const promise2 = farm.foo('param-2');129    // Send different responses for each call (from the same child).130    replySuccess(0, 'worker-0');131    replySuccess(0, 'worker-1');132    replySuccess(0, 'worker-2');133    // Check that all the calls have been received by the same child).134    assertCallsToChild(135      0,136      ['foo', 'param-0'],137      ['foo', 'param-1'],138      ['foo', 'param-2'],139    );140    // Check that responses are correct.141    expect(await promise0).toBe('worker-0');142    expect(await promise1).toBe('worker-1');143    expect(await promise2).toBe('worker-2');144  });...

index-integration.test.js

Source:index-integration.test.js

...16}17function replySuccess(i, result) {18  mockForkedProcesses[i].emit('message', [PARENT_MESSAGE_OK, result]);19}20function assertCallsToChild(childNum, ...calls) {21  expect(mockForkedProcesses[childNum].send).toHaveBeenCalledTimes(22    calls.length + 1,23  );24  calls.forEach(([methodName, ...args], numCall) => {25    expect(26      mockForkedProcesses[childNum].send.mock.calls[numCall + 1][0],27    ).toEqual([CHILD_MESSAGE_CALL, true, methodName, args]);28  });29}30beforeEach(() => {31  mockForkedProcesses = [];32  jest.mock('child_process', () => ({33    fork() {34      const forkedProcess = mockBuildForkedProcess();35      mockForkedProcesses.push(forkedProcess);36      return forkedProcess;37    },38  }));39  Farm = require('../index').default;40});41afterEach(() => {42  jest.resetModules();43});44it('calls a single method from the worker', async () => {45  const farm = new Farm('/tmp/baz.js', {46    exposedMethods: ['foo', 'bar'],47    numWorkers: 4,48  });49  const promise = farm.foo();50  replySuccess(0, 42);51  expect(await promise).toBe(42);52});53it('distributes sequential calls across child processes', async () => {54  const farm = new Farm('/tmp/baz.js', {55    exposedMethods: ['foo', 'bar'],56    numWorkers: 4,57  });58  // The first call will go to the first child process.59  const promise0 = farm.foo('param-0');60  assertCallsToChild(0, ['foo', 'param-0']);61  replySuccess(0, 'worker-0');62  expect(await promise0).toBe('worker-0');63  // The second call will go to the second child process.64  const promise1 = farm.foo(1);65  assertCallsToChild(1, ['foo', 1]);66  replySuccess(1, 'worker-1');67  expect(await promise1).toBe('worker-1');68});69it('distributes concurrent calls across child processes', async () => {70  const farm = new Farm('/tmp/baz.js', {71    exposedMethods: ['foo', 'bar'],72    numWorkers: 4,73  });74  // Do 3 calls to the farm in parallel.75  const promise0 = farm.foo('param-0');76  const promise1 = farm.foo('param-1');77  const promise2 = farm.foo('param-2');78  // Check that the method calls are sent to each separate child process.79  assertCallsToChild(0, ['foo', 'param-0']);80  assertCallsToChild(1, ['foo', 'param-1']);81  assertCallsToChild(2, ['foo', 'param-2']);82  // Send different responses from each child.83  replySuccess(0, 'worker-0');84  replySuccess(1, 'worker-1');85  replySuccess(2, 'worker-2');86  // Check87  expect(await promise0).toBe('worker-0');88  expect(await promise1).toBe('worker-1');89  expect(await promise2).toBe('worker-2');90});91it('sticks parallel calls to children', async () => {92  const farm = new Farm('/tmp/baz.js', {93    computeWorkerKey: () => '1234567890abcdef',94    exposedMethods: ['foo', 'bar'],95    numWorkers: 4,96  });97  // Do 3 calls to the farm in parallel.98  const promise0 = farm.foo('param-0');99  const promise1 = farm.foo('param-1');100  const promise2 = farm.foo('param-2');101  // Send different responses for each call (from the same child).102  replySuccess(0, 'worker-0');103  replySuccess(0, 'worker-1');104  replySuccess(0, 'worker-2');105  // Check that all the calls have been received by the same child).106  assertCallsToChild(107    0,108    ['foo', 'param-0'],109    ['foo', 'param-1'],110    ['foo', 'param-2'],111  );112  // Check that responses are correct.113  expect(await promise0).toBe('worker-0');114  expect(await promise1).toBe('worker-1');115  expect(await promise2).toBe('worker-2');...

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