tdd

# TDD Red. Green. Refactor. In that order, every time. ## Hard Rules - No production code without a failing test first. - If production code was written before its test, delete it and start over with a failing test. - Never skip the red step. A test that has never failed proves nothing. ## Cycle For each unit of behavior: 1. **Red** — Write a test for the next behavior. Run it. It must fail. Read the failure message — it should describe the missing behavior. 2. **Green** — Write the minimum production code to make the test pass. Nothing more. Run the test. Apply the `verify` skill. 3. **Refactor** — Clean up both test and production code. Run the test again. Still green? Done. Apply the `verify` skill. Then pick the next behavior and repeat. ## Rules for Each Step **Red:** - Test one behavior, not one function. Name the test after what the system should do, not what the function is called. - The test must fail for the right reason — a missing method, wrong return value, unmet condition. Not a syntax error or import failure. - If the test passes immediately, it's not testing new behavior. Delete it or pick a different behavior. **Green:** - Write the simplest code that passes. Hardcode if needed — the next test will force generalization. - Do not add code "while you're in there." If it's not required by a failing test, it doesn't exist yet. - Do not refactor during green. Pass first, clean second. **Refactor:** - Remove duplication between test and production code. ...