Practices of an Agile Developer

  35   Attack Problems in Isolation

“Stepping line by line through a massive code base is pretty scary. But the only way to debug a significant problem is to look at the entire system. All at once. After all, you don’t know where the problem may be, and that’s the only way to find it.”

One of the positive side effects of unit testing (Chapter 5, ​Agile Feedback​) is that it forces you to layer your code. To make your code testable, you have to untangle it from its surroundings. If your code depends on other modules, you’ll use mock objects ...