Individual skill
test-driven-development
Use when implementing a feature, fixing a bug, or changing behavior — write a failing test first, watch it fail, write minimal code to pass, then refactor. Adds Kent Beck's Tidy First (separate structural vs behavioral changes) and a Canon test list. Language-agnostic core; per-language notes under references/languages/. Not for throwaway prototypes, generated code, or pure config changes (ask first).
plugins/yyykf/spellbook-skills/skills/test-driven-development/SKILL.md
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SKILL.mdcore · 10,516 bytesreferences/languages/go.mddoc · 12,237 bytesreferences/languages/java.mddoc · 9,535 bytesreferences/languages/python.mddoc · 10,831 bytesreferences/languages/rust.mddoc · 11,117 bytesreferences/languages/typescript.mddoc · 9,512 bytesreferences/testing-anti-patterns.mddoc · 8,251 bytes
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# Test-Driven Development (TDD)
## Overview
Write the test first. Watch it fail. Write minimal code to pass. Then tidy.
**Core principle:** If you didn't watch the test fail, you don't know if it tests the right thing.
**Announce at start:** "I'm using the test-driven-development skill to drive this change test-first."
This skill is **language-agnostic**. The discipline below holds in every language; concrete framework, runner, and idiom examples live in [references/languages/](references/languages/) — load the one matching your project.
## Prerequisites
