mockRestore does not clear a jest.spyOn().mockImplementation mock

Question

I am mocking Date.now() implementation returning a specific date however, after the test is done the afterAll + mockRestore() doesn't quite rid of the mock.

When I run another test the date now is still mocked to 1626764400000. Is there a different function I have to use to reset the mock? I have already used: mockReset, mockClear, jest.clearAllMocks.

beforeAll((): void => {
  jest.spyOn(Date, 'now').mockImplementation(() => 1626764400000);
});

afterAll((): void => {
  jest.clearAllMocks();
  jest.spyOn(Date, 'now').mockRestore();
});

Does this answer your question? [How to reset or clear a spy in Jest?](https://stackoverflow.com/questions/53350382/how-to-reset-or-clear-a-spy-in-jest) — MuzaffarShaikh, Nov 30 '21 at 09:30
1. where did you mock Date.now? in which file? Where the another test is placed? — Andrey Nelubin, Nov 30 '21 at 15:35
@LazioTibijczyk can you show it? Without the bodies of tests — Andrey Nelubin, Dec 01 '21 at 11:47

score 0 · Answer 1 · answered Jul 17 '22 at 00:24

0

I have solved a similar issue by calling mockRestore of the returned value of the jest.spyOn(), that also returns a Jest mock function. Oficcial docs.

answered Jul 17 '22 at 00:24

Norayr Ghukasyan

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This answer did not work for me. I tried: `let spy = jest.spyOn(testFeature.Service, 'getObj').mockImplementation(() => {return 'junk';});` `spy.mockRestore();` It was not restored in later tests. – OpticalFlow Feb 01 '23 at 18:29

score 0 · Answer 2 · answered Apr 21 '23 at 07:27

I think you should use jest.restoreAllMocks(). As the docs says

since Jest 21.1.0 Restores all mocks back to their original value. Beware that jest.restoreAllMocks() only works when mock was created with jest.spyOn;

So your code should be like :

 beforeEach(() => {    
    jest.restoreAllMocks();
 });

mockRestore does not clear a jest.spyOn().mockImplementation mock

2 Answers2