Setup

Write a test, get it to pass, clean up the design. That’s all there is to TDD. Yet these three simple steps embody a significant amount of sophistication. Understand how to take advantage of TDD, and you will be rewarded with many benefits. Fail to heed what others have learned, and you will likely give up on TDD.

Rather than let you flounder, I’d like to guide you through test-driving some code in order to help you understand what happens at each step. You’ll learn best by coding along with the example in this chapter. Make sure you’ve set up your environment properly (see Chapter 1, ​Global Setup​).

While not large, the example we’ll work through isn’t useless or trivial (but it’s also not rocket science). It provides many teaching points and demonstrates how TDD can help you incrementally design a reasonably involved algorithm.

I hope you’re ready to code!