Mock
The final type of fake object is a mock. The difference between a mock and a stub is where the verification is done. With a stub, our test must check if the state is correct after the act. With a mock object, the responsibility for testing the asserts falls to the mock itself. Mocks are another place where it is useful to leverage a mocking library. We can, however, build the same sort of thing, simply, ourselves:
class MockCredentialFactory { constructor() { this.timesCalled = 0; } Create() { this.timesCalled++; } Verify() { assert(this.timesCalled == 3); } }
This mockCredentialsFactory
class takes on the responsibility of verifying the correct functions were called. This is a very simple sort of approach to mocking and can be used as such: ...
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