test-driven-development

Test-driven development prevents regressions by requiring a failing test before writing production code, codifying expected behavior to clarify design intent and provide a safety net for future refactoring.

You apply the red-green-refactor cycle by first writing a failing test for the new behavior, then implementing minimal production code to satisfy that test, and finally refactoring the codebase while maintaining passing tests.

Yes, test-driven development enforces minimal production code that only exists to satisfy the specific tests written, effectively preventing feature creep and ensuring disciplined test maintenance across the codebase.

Yes, you can use test-first development for refactoring by applying the red-green-refactor workflow to behavior changes across codebases, using the codified tests as a safety net to verify functionality remains intact.

Documenting behavior through tests before implementation clarifies design intent upfront and prevents feature creep, ensuring the production code strictly adheres to expected behaviors rather than retroactively validating untested logic.