test-driven-development

To prove code behavior, write an executable test that captures the desired contract and fails first, then implement the minimal code required to pass it. This red-green-refactor cycle ensures test-driven correctness before software changes are accepted.

Writing unit tests for bug fixes starts by creating a failing test that reproduces the specific defect, then fixing the implementation to make it pass. This captures observable behavior and prevents future regressions throughout the codebase.

Test-driven development handles edge cases and integration tests by translating observable behavior and boundary conditions into maintainable test cases. This captures software contracts across integration layers to ensure comprehensive validation.

Yes, you can use this test-driven approach for both features and defect resolution. The red-green-refactor cycle applies across the entire development workflow, capturing contracts and generating minimal verification evidence for any software behavior modification.

You should not use a test-first workflow when exploring unfamiliar prototypes where observable behavior and contracts are undefined. The approach requires clear expectations to generate failing tests and validate specific software behavior.