test-driven-development

Test-driven development prevents untested production code by enforcing a strict red-green-refactor cycle where you must write and verify a failing test before implementing any feature, bug fix, or refactoring change.

The red-green-refactor cycle requires writing a failing test first, writing the minimal production code to pass that test, and then refactoring. This workflow eliminates untested code and reduces post-deployment bugs.

Avoid testing anti-patterns by not testing mock behavior, avoiding test-only methods in production code, and preventing incomplete mocks. Testing mock behavior creates false confidence instead of verifying actual functionality.

No, test-driven development requires mandatory test failure verification before implementation for all tasks with no exceptions for simple changes. This prevents rationalized shortcuts like testing later or skipping tests for trivial fixes.

Fix bugs using test-first development by writing a failing test that validates the expected behavior, implementing the minimal code to pass the test, and verifying the fix works without breaking existing functionality through automated testing.

Verifying test failure before implementation ensures the test actually catches the bug or missing feature. Without failure verification, you risk writing tests that pass regardless of code correctness, creating false confidence in untested production code.