test-driven-development

Test-driven development is a workflow enforcing test-first discipline by following the RED-GREEN-REFACTOR cycle. You write a failing test, implement minimal code to pass it, and then refactor with confidence to ensure correct, maintainable code.

To start writing failing tests before implementing features, apply the test-first workflow by defining expected behavior as a failing test case, then writing minimal implementation code to turn the failing test green.

Test-driven development works for refactoring existing codebases by maintaining confidence during evolution. The test-first discipline ensures you have passing tests verifying correct behavior before and after you modify the code.

The best way to prevent regressions when fixing bugs is applying test-driven development. You write a failing test reproducing the bug, implement the fix to pass the test, and refactor safely to ensure the regression is permanently locked out.

You can use test-first development for standard software engineering tasks including new features, bug fixes, and refactors. The test-driven workflow applies broadly to standard codebases to drive design and ensure code reliability.