Refactor with Tests
Refactoring is the practice of improving the code’s structure without changing its behavior. And the only way to do that safely is a robust test suite. When tests are present, small renames, splitting large functions, extracting classes, inverting dependencies, and moving modules around become low-risk activities. Tests let us reshape architecture while keeping behavior intact. That confidence is why refactoring pairs so well with test-first practices: tests become the specification you can rely on during change. ...