Test-Driven Development: More Than a Buzzword

Before starting programming classes, I had heard of test-driven development (TDD). I was told it was a good practice, similar to the way I was told to eat my green vegetables when I was younger. That’s why up until today, I thought it was just another business buzzword.

Today we began to cover the basic principles of object-oriented programming (OOP). Even in a simple app with 3 related classes, you can begin to see the complexity unfold. With complexity comes fragility … and that’s where TDD comes into play.

Jason Arhart does a good job explaining TDD in his speakerdeck. Essentially, the process entails writing a simple test, letting it fail, and then writing the minimum amount of code to make the spec pass. He deftly sum’s it up in a cyclical diagram describing the “Red”, “Green”, “Refactor” pattern. By following this method, you get a solid baseline of tests coupled with functioning code.

It’s this constant cycle that allows programs and their programmers to evolve. To this end, I think its better to think of it as an upward spiral. With this approach, the process may be a bit slower, but ultimately the sky is the limit.

Jason describes TDD as a process that, “turns the ‘traditional’ on its head.” I consider myself lucky to start learning in an environment where TDD is the convention. It feels great to pass each spec in a test suite and incrementally move from red to green. I liken it to the feeling you get when gambling and winning, only here you get to bet with the house.

If you want to learn more about TDD, Jason has another speakerdeck that describes the Ruby specific testing framework: RSpec. We will be using more of RSpec as the semester continues at the Flatiron school.