Your Momma So Fat All Her Tests Are Integration Tests
No two engineers can agree what is or is not a unit test, an integration test, or an acceptance test, or the difference between them. This is one of the immutable laws of the universe. So, in the grand tradition of my craft, I'm going to stir the pot further by throwing my own take into the ring.
The key to grokking unit and integration tests, in my opinion, is not to think of them individually, as distinct things with their own definitions that can be known on their own terms. Instead, I think of them as being related by a recursive definition, holisitcally. On their face, integration tests are, intrinsically, more complex and fragile than unit tests. They combine multiple moving pieces into one. Oftentimes, they need fixtures or some encompassing test harness, or are otherwise awkwardly contorted to fit environmental constraints. It stands to reason that anything that lets us reduce the need for integration tests without sacrificing coverage is a g