Bumping Into Discovery Testing

Until recently, what I mostly knew about test-driven development was the concept of red-green-refactor, unit testing application code while building them from the bottom-up. Likewise, I also thought that mocking was only all about mocks, fakes, stubs, and spies, tools that assist us in faking integrations so we can focus on what we really need to test. Apparently there is so much more to TDD and mocks that many programmers do not put into use.

Justin Searls calls it discovery testing. It’s a practice that’s attempts to help us build carefully-designed features with focus, confidence, and mindfulness, in a top-down approach. It breaks feature stories down into smaller problems right from the very beginning and forces programmers to slow down a little bit, enough for them to be more thoughtful about the high-level design. It uses test doubles to guide the design, which shapes up a source tree of collaborators and logical leaf nodes as development go. It favors rewrites over refactors, and helps us become aware of nasty redundant coverage with our tests.

And it categorizes TDD as a soft skill, rather than a technical skill.

He talks about it in more depth in a series of videos, building Conway’s Game of Life (in Java) as a coding exercise. He’s also talked about how we are often using mocks the wrong way, and shared insight on how we can write programs better.

Discover testing is fascinating, and has a lot of great points going for it. I feel that it takes the concept of red-green-refactor further and drives long-term maintainable software right from the start. I want to be good at it eventually, and I know I’d initially have to practice it long enough to see how much actual impact it has.