Refactor: Test Safety Net

Ensure adequate test coverage before making changes.

Pre-Refactoring Test Checklist

1. Coverage Assessment

• What's the current test coverage?
• Which paths are untested?

2. Test Types Needed

| Type | Purpose | When Required | |------|---------|---------------| | Unit | Function behavior | Always | | Integration | Component interaction | Cross-module changes | | Snapshot | UI/Output structure | View refactoring | | Regression | Known bug prevention | Bug-prone areas |

3. Minimal Safety Net

Priority 1: Happy path test Priority 2: Error handling test Priority 3: Edge case test

Rules

1. Never refactor without tests on the target code
2. Add tests BEFORE changes, not after
3. Characterization tests capture behavior, not correctness
4. Run tests after each small step