diff --git a/CHANGELOG.md b/CHANGELOG.md index 79bf4ef86472..fd78c73d1236 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -16,6 +16,9 @@ ([#5670](https://github.com/facebook/jest/pull/5670)) * `[expect]` Add inverse matchers (`expect.not.arrayContaining`, etc., [#5517](https://github.com/facebook/jest/pull/5517)) +* `[jest-cli]` Add `isSerial` property that runners can expose to specify that + they can not run in parallel + [#5706](https://github.com/facebook/jest/pull/5706) ### Fixes diff --git a/docs/Configuration.md b/docs/Configuration.md index dc70b54fd4f6..e448493e48c9 100644 --- a/docs/Configuration.md +++ b/docs/Configuration.md @@ -703,6 +703,10 @@ async runTests( ): Promise ``` +If you need to restrict your test-runner to only run in serial rather then being +executed in parallel your class should have the property `isSerial` to be set as +`true`. + ### `setupFiles` [array] Default: `[]` diff --git a/packages/jest-cli/src/__tests__/test_scheduler.test.js b/packages/jest-cli/src/__tests__/test_scheduler.test.js index 352e62a62771..6170d087215e 100644 --- a/packages/jest-cli/src/__tests__/test_scheduler.test.js +++ b/packages/jest-cli/src/__tests__/test_scheduler.test.js @@ -12,6 +12,20 @@ import TestScheduler from '../test_scheduler'; import SummaryReporter from '../reporters/summary_reporter'; jest.mock('../reporters/default_reporter'); +const mockSerialRunner = { + isSerial: true, + runTests: jest.fn(), +}; +jest.mock('jest-runner-serial', () => jest.fn(() => mockSerialRunner), { + virtual: true, +}); + +const mockParallelRunner = { + runTests: jest.fn(), +}; +jest.mock('jest-runner-parallel', () => jest.fn(() => mockParallelRunner), { + virtual: true, +}); test('.addReporter() .removeReporter()', () => { const scheduler = new TestScheduler({}, {}); @@ -21,3 +35,45 @@ test('.addReporter() .removeReporter()', () => { scheduler.removeReporter(SummaryReporter); expect(scheduler._dispatcher._reporters).not.toContain(reporter); }); + +test('schedule tests run in parallel per default', async () => { + const scheduler = new TestScheduler({}, {}); + const test = { + context: { + config: { + runner: 'jest-runner-parallel', + }, + hasteFS: { + matchFiles: jest.fn(() => []), + }, + }, + path: './test/path.js', + }; + const tests = [test, test]; + + await scheduler.scheduleTests(tests, {isInterrupted: jest.fn()}); + + expect(mockParallelRunner.runTests).toHaveBeenCalled(); + expect(mockParallelRunner.runTests.mock.calls[0][5].serial).toBeFalsy(); +}); + +test('schedule tests run in serial if the runner flags them', async () => { + const scheduler = new TestScheduler({}, {}); + const test = { + context: { + config: { + runner: 'jest-runner-serial', + }, + hasteFS: { + matchFiles: jest.fn(() => []), + }, + }, + path: './test/path.js', + }; + + const tests = [test, test]; + await scheduler.scheduleTests(tests, {isInterrupted: jest.fn()}); + + expect(mockSerialRunner.runTests).toHaveBeenCalled(); + expect(mockSerialRunner.runTests.mock.calls[0][5].serial).toBeTruthy(); +}); diff --git a/packages/jest-cli/src/test_scheduler.js b/packages/jest-cli/src/test_scheduler.js index 2f7ec55002c0..ed784ca06904 100644 --- a/packages/jest-cli/src/test_scheduler.js +++ b/packages/jest-cli/src/test_scheduler.js @@ -192,7 +192,7 @@ export default class TestScheduler { onResult, onFailure, { - serial: runInBand, + serial: runInBand || Boolean(testRunners[runner].isSerial), }, ); }