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