don't mock what you don't own, IMHO the classic approach is to use your own domain abstractions, mock those in unit tests, test the domain abstractions e.g. wi

don't mock what you don't own, IMHO the classic approach is to use your own domain abstractions, mock those in unit tests, test the domain abstractions e.g. with an in-memory DB, and have some integration tests verify that everything is plugged together correctly making assertions about your own, domain-inspired APIs makes your tests less brittle and more readable than using "receive_message_chain"