Your Code as a Crime Scene, Second Edition, 2nd Edition

Refactor Complex Code via Simple Steps

The code smells seen so far all stem from overly long classes and functions. Take ReactFiberCommitWork as a prominent example: its three central functions span 200 to 400 lines of code each. This raises the question: should we prefer many small methods—the logical outcome of the recommended refactorings—or is it better to keep related code in one large chunk?

The main advantage of modularizing a piece of code isn’t that we get shorter functions. Rather, it’s about transforming the context, as discussed in design to isolate change. By extracting cohesive, well-named functions, we introduce chunks into our design, as shown in the following figure. These chunks let us reason more effectively about the problem ...