tdd-plan

Productivity

Create implementation plans following TDD methodology with test-first approach. Use this skill when creating implementation plans in plan mode, when user requests TDD-based development, or when planning features that require test-driven development. Ensures tests are planned BEFORE implementation code.

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Source SKILL.md: https://github.com/majiayu000/claude-skill-registry/blob/HEAD/skills/data/tdd-plan/SKILL.md

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TDD Implementation Plan

このスキルは、実装計画をTDD（テスト駆動開発）の原則に従って構成します。

Core Principle

テストが先、実装が後 - Tests come FIRST, implementation comes AFTER.

Plan Structure (Required Order)

✅ Correct TDD Order

Step	Phase	Content
1	Red Phase	Test files - Write failing tests first
2	Green Phase	Implementation - Minimal code to pass tests
3	Refactor Phase	Verification & cleanup

❌ Wrong Order (Avoid)

Step	Content	Problem
1-3	Implementation	Code before tests
4	Tests	Tests last = NOT TDD

Plan Template

# Plan: [Feature Name]

## Goal
[What this plan achieves]

---

## Files to Modify

### 1. Test Files (Red Phase - FIRST)
| File | Change |
|------|--------|
| tests/... | Add failing tests for [feature] |

### 2. Implementation (Green Phase)
| File | Change |
|------|--------|
| src/... | Implement to pass tests |

---

## Implementation Steps

### Step 1: Test Files (Red Phase - 失敗するテストを先に書く)
- Write tests for expected behavior
- **Tests MUST fail initially** (no implementation yet)

### Step 2: Implementation (Green Phase - テストを通す最小実装)
- Implement minimal changes to pass tests
- Keep implementation simple

### Step 3: Verification (Refactor Phase - 品質改善)
- Run all tests
- Type checking (if applicable)
- Code quality review

Checklist Before Completing Plan

Test files are listed BEFORE implementation files
Step 1 is always about writing tests
Each implementation step references which tests it should pass
Red → Green → Refactor phases are clearly labeled

Notes

テスト言語・フレームワークはプロジェクトの対象言語に依存
テスト粒度（unit/integration等）はプロジェクトの性質に依存
具体的なテストコマンドはプロジェクトの設定に従う