Working Effectively with Legacy Code

Chapter 16: I Don’t Understand the Code Well Enough to Change It

Stepping into unfamiliar code, especially legacy code, can be scary. Over time, some people become relatively immune to the fear. They develop confidence from confronting and slaying monsters in code over and over again, but it is tough not to be afraid. Everyone runs into demons that they can’t slay from time to time. If you dwell on it before you start to look at the code, that makes it worse. You never know whether a change is going to be simple or a weeklong hair-pulling exercise that leaves you cursing the system, your situation, and nearly everything around you. If we understood everything we need to know to make our changes, things would go smoother. How can we get that understanding? ...