test-driven-development

Test-driven development is a workflow where you write a failing test first, implement minimal production code to pass it, and then refactor. This iterative cycle enforces behavior validation through automated tests before any feature logic is built.

You enforce test-first development by requiring a failing test that specifies desired behavior before writing any production code. This disciplined workflow applies clear guardrails across new features, bug fixes, and refactors to catch regressions early.

Test-driven development requires minimal mocks to validate actual behavior. You write a failing test specifying the desired behavior, then implement the minimal code to pass it, relying on automated validation rather than extensive mocking setups.

The best way to catch regressions during refactoring is applying the red-green-refactor cycle. By maintaining automated tests that validate behavior first, you get fail-fast feedback that ensures incremental code changes remain reliable across refactors.

A strict test-driven development workflow may not suit exploratory prototyping where desired behavior is undefined. The approach requires a clear behavioral specification upfront, making it less ideal for rapid experimentation before settling on final software requirements.