> 1. Write a test first so that its failure state is proven. This is useful for to me only when fixing existing code but not when writing new code. Before I wr

> 1. Write a test first so that its failure state is proven. This is useful for to me only when fixing existing code but not when writing new code. Before I write the implementation, it is obvious the test would fail. By not having to code the test first, I have more flexibility on changing the API if needed.