Software Design X-Rays

Solutions: Coupling in Time

Here are the solutions to the exercises in Chapter 3, ​Coupling in Time: A Heuristic for the Concept of Surprise​.

Learn from the Change Patterns in a Codebase

There’s a strong degree of change coupling between the test cases for the Visual Basic and C# compilers, where files with the same name but located in different folders and implemented in different programming languages are changed together. If you join the project, you use this information so that you can plan changes to both parts of the code; the compiler won’t be able to detect the omission of a test.

We also note that the change coupling between the test suites is deliberate. Last year I had the opportunity to ask some of the lead developers on Roslyn ...