Working Effectively with Legacy Code

Glossary

change point    A place in code where you need to make a change.

characterization test    A test written to document the current behavior of a piece of software and preserve it as you change its code.

coupling count    The number of values that pass in and out of a method when it is called. If there is no return value, it is the number of parameters. If there is, it is the number of parameters plus one. Coupling count can be a very useful thing to compute for small methods you’d like to extract if you have to extract without tests.

effect sketch    A small hand-drawn sketch that shows what variables and method return values can be affected by a software change. Effect sketches can be useful when you are trying to decide where to write ...