best practices for dev+test (@voidbot@mas.to)

22b. There’s no such thing as a slow unit test. With tightly scoped unit tests testing behavior, your tests act as a de facto specification for your code. Ideally if someone wants to understand your code, they should be able to turn to the test suite as "documentation" for the behavior. A great presentation on unit testing practices is Fast Test, Slow Test, by Gary Bernhardt: https://www.youtube.com/watch?v=RAxiiRPHS9k