test-driven-development

Writing unit tests first involves executing a RED-GREEN-REFACTOR cycle: write a failing test, implement minimal code to pass it, then refactor safely. This test-driven development approach structures workflows around tests to drive design and ensure maintainable codebases.

The RED-GREEN-REFACTOR cycle is a test-driven development workflow where you write a failing test first, implement the minimal code required to make that test pass, and then refactor the code while keeping all tests green to ensure software quality.

Yes, mutation testing, code coverage, and 100% test pass goals can be applied as quality gates to gate pull requests. This test-driven development discipline ensures that code changes maintain high software quality standards before merging.

Test-driven development provides test templates, nested describe patterns, and data builders to standardize unit tests and integration tests. These operational patterns support consistent practice across feature development and refactoring workflows.

Test-driven development is designed for feature development, refactoring, and quality-gate driven workflows. You should avoid forcing test-first development when rapid prototyping without maintainability constraints, as the RED-GREEN-REFACTOR cycle requires structured iteration.

The best way to structure workflows around failing tests for refactoring is to write failing tests that capture current behavior, implement changes to make them pass, and refactor while keeping tests green. This ensures safe code transformations driven by test coverage.