wallacedobbs428/refactor

Refactor Skill

Surgical code refactoring — gradual improvements to structure and maintainability without altering external behavior.

Golden Rules

1. Behavior is preserved — no functional changes
2. Small steps — incremental improvements
3. Version control is your friend — commit often
4. Tests are essential — verify at each step
5. One thing at a time — single responsibility per refactor

When NOT to Refactor

• Under tight deadlines
• On critical production code lacking tests
• Without clear purpose

Code Smells and Solutions

1. Long methods — Extract focused functions from bloated routines
2. Duplication — Consolidate repeated logic into shared utilities
3. Large classes — Divide responsibilities across specialized classes
4. Parameter overload — Group related parameters into objects
5. Feature envy — Move methods to objects that own their data
6. Primitive obsession — Replace basic types with domain-specific classes
7. Magic values — Replace unexplained numbers with named constants
8. Nested conditionals — Use guard clauses and early returns
9. Dead code — Remove unused functions and imports
10. Inappropriate intimacy — Reduce deep object access through encapsulation

Process Framework

1. Prepare — Ensure tests exist, commit current state
2. Identify — Understand the smell
3. Refactor — Small increments
4. Verify — Test thoroughly
5. Clean up — Update documentation

Common Refactoring Operations

• Extract method/function
• Introduce parameter object
• Replace conditionals with polymorphism
• Move method to appropriate class
• Extract interface/protocol
• Inline unnecessary abstractions
• Rename for clarity