Martin Fowler has updated his paper “Mocks aren’t Stubs” to better explain the difference between the classic TDDer and the mockist TDDer. These two schools are often so fundamentally different that a practioner of one doesn’t even understand how the other would work effectively. This paper does a great job presenting each philosophy.

I’m a mockist. I’m slightly uneasy about my position, only because some of the most talented developers I know are classicists. In various conversations, however, I have yet to hear an argument that sways me.