Table of Contents for

Your Code as a Crime Scene

Evaluate the Growth Patterns

When you’re analyzing complexity trends, the interesting thing isn’t the numbers themselves but the shape of the evolutionary curve.

The following figure shows the shapes you’re most likely to find in a typical codebase. The dip in the curve in Case B generally is a sign of a refactoring, because the code got simpler. Case C is also common because there’s little change in the file’s complexity. We have a stable module where we make small tweaks and changes. I expect to see this pattern in a configuration file.

Case A is a warning sign. As the file gets more complex, it becomes harder to understand.

To know how bad it is, we look at descriptive statistics—such as standard deviation—as we did earlier. A high standard deviation points to many complex blocks of conditional logic, which is the kind of code that’s hard to understand and maintain.