test-driven-development

Test-driven development is a workflow where you write a failing test first, implement minimal code to pass it, and then refactor. This Red-Green-Refactor cycle ensures your tests drive the software design and quality from the very start of feature development.

To start applying TDD for bug fixes, you first write a unit test that captures the bug and fails. You then write the minimal code required to make that test pass, ensuring the fix is verified and locked in against future regressions before refactoring.

Yes, you can use test-first development for refactoring by relying on your existing unit tests to remain green throughout the process. The workflow guides you to refactor code while continuously verifying that all tests stay passing, ensuring structural changes do not break functionality.

Common testing anti-patterns in unit testing include writing tests that are hard to read, testing implementation details rather than behavior, and creating overly complex setups. The TDD workflow provides best practices for clear naming and writing meaningful tests to avoid these pitfalls.

You should avoid the Red-Green-Refactor cycle when exploring unfamiliar APIs or throwing away prototype code, because writing failing tests first for code you intend to immediately discard adds unnecessary overhead without providing quality assurance value.