How to use assertCallsToChild method in Jest

Best JavaScript code snippet using jest

thread-integration.test.js

Source:thread-integration.test.js Github

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...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 });...

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process-integration.test.js

Source:process-integration.test.js Github

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...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 });...

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index-integration.test.js

Source:index-integration.test.js Github

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...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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