test-driven-development

What problem does it solve? Code written before tests often ships with unverified behavior, hidden bugs, and no regression safety net. This Skill enforces a strict test-first workflow so every feature and bugfix is proven by a failing test before any production code exists. ## Core Features & Use Cases - Red-Green-Refactor Enforcement: Guides the full TDD cycle—write a failing test, verify it fails for the right reason, write minimal code to pass, then refactor while staying green. - Rationalization Detection: Lists common excuses for skipping TDD (e.g., "I'll test after", "too simple to test") and explains why each one fails, keeping the workflow honest. - Testing Anti-Pattern Reference: Ships a companion guide covering mock-behavior testing, test-only production methods, incomplete mocks, and over-mocking, with gate functions to catch violations. - Use Case: When fixing a bug like an empty email being accepted, write a failing test reproducing it first, watch it fail, implement the minimal validation fix, and confirm the suite stays green. ## Quick Start Ask the AI to implement a new feature or bugfix using strict test-driven development with a failing test written first.