Refactoring Skill

Common Patterns

• •Extract Utility: Moving logic from Components or API routes to src/lib.
• •Custom Hooks: Extracting stateful logic from components to src/hooks.
• •Component Composition: Breaking large "God Components" into smaller sub-components in src/components.

Code Smells to Detect

• •Prop Drilling: Passing data through >3 layers (Suggest Context or Hooks).
• •Hardcoded Strings: Magic numbers/strings (Suggest Constants or Config).
• •Duplicate Logic: Same validation or formatting used in multiple places.
• •Large Files: Files >300 lines (unless it's a complex config or main layout).

Procedure

1. •Guard: Ensure tests exist for the code being refactored.
2. •Plan: Identify the specific smell and the target pattern.
3. •Execute: Make small, atomic changes.
4. •Verify: Run tests after each change.
5. •Clean: Remove unused imports or dead code.

Testing

• •Regression: Existing tests MUST pass.
• •New Tests: If the refactor exposes new units (e.g. a new utility function), add unit tests for it.