Jest

Jest

Mocking tips

mock functions - https://jestjs.io/docs/jest-object#mock-functions

when you mocking 3rd party lib and wanna clear mock state(or data) you should use jest.clearAllMocks() instead of `jest.restoreAllMocks()` or `jest.resetAllMocks()`

because we can't just restore 3rd party library statement. we should re-init instance.

fake timer - https://jestjs.io/docs/timer-mocks