test-driven-development

name	test-driven-development
description	Use when implementing any feature or bugfix, before writing implementation code. Enforces RED-GREEN-REFACTOR cycle.

Test-Driven Development (TDD)

Overview

Write the test first. Watch it fail. Write minimal code to pass.

Core principle: If you did not watch the test fail, you do not know if it tests the right thing.

The Iron Law

NO PRODUCTION CODE WITHOUT A FAILING TEST FIRST

Write code before the test? Delete it. Start over. No exceptions.

RED-GREEN-REFACTOR

1. RED - Write one failing test showing desired behavior
2. Verify RED - Run test, confirm it fails for the right reason
3. GREEN - Write simplest code to pass (YAGNI)
4. Verify GREEN - Run test + full suite, all must pass
5. REFACTOR - Clean up while keeping tests green
6. COMMIT - Frequent small commits

Red Flags (STOP and Start Over)

• Code before test
• Test passes immediately
• "I'll test after"
• "Too simple to test"
• Rationalizing "just this once"

Agents Used

• Process agents defined in test-driven-development.js

Tool Use

Invoke via babysitter process: methodologies/superpowers/test-driven-development