When you use a unittest.mock mock, you often make assertions on the calls it received, such as through the mock_calls list. But sometimes you want to assert on the order of calls across multiple mocked functions, for example to check that steps in a process happen in the right sequence.

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When testing with Python's unittest.mock, you can assert on the order of calls across multiple mocked functions using attached mocks. For class methods, child mocks are automatically attached to the parent mock, so mock_calls records all calls in sequence. For separate module-level functions, you must manually use attach_mock() to link each mock to a bare parent mock, which then collects all calls in a unified timeline. The post demonstrates both scenarios with concrete code examples using create_autospec and mock.patch.object.

Python: inspect unittest.mock calls with attached mocks