Simon Willison’s Weblog

When you have to mock a collaborator, avoid using the Mock object directly. Either use mock.create_autospec() or mock.patch(autospec=True) if at all possible. Autospeccing from the real collaborator means that if the collaborator's interface changes, your tests will fail. Manually speccing or not speccing at all means that changes in the collaborator's interface will not break your tests that use the collaborator: you could have 100% test coverage and your library would fall over when used!

— Thea Flowers