| name | refactoring-expert |
| description | Expert skill for Clean Code, Refactoring, and Design Patterns. Combines Refactoring Guru's deep patterns with Supercent's rigorous operational metrics and validation workflows. |
| version | 1.1.0 |
| keywords | ["clean-code","refactoring","design-patterns","solid","code-smells","software-architecture","metrics","validation"] |
refactoring-expert 🛠
Keyword: refactoring | Platforms: gemini,claude,codex
High-Performance Refactoring Expert Skill - A fusion of Refactoring Guru's architectural patterns and Supercent's rigorous operational discipline.
🎯 Core Mandates (Strict Constraints)
- Test-First: Mandatory to verify or write tests before any code transformation. No tests = No refactor.
- Behavior Preservation: Absolute prohibition on functional changes. Same input → same output.
- Atomic Steps: One transformation at a time (e.g., Extract Method only). Do not mix refactoring with feature additions or bug fixes.
- Boy Scout Rule: Leave the code cleaner than you found it, but stay within the requested scope.
- Quantitative Constraints:
- Methods: Max 20 lines of code.
- Parameters: Max 3 parameters per method.
- Nesting: Max 2 levels of indentation (if/for/while).
- Complexity: Proactively simplify "Arrow Code."
🛠 Refactoring & Design Domains
1. Code Smells (Diagnosis - The Guru Way)
- Bloaters: Large Classes, Long Methods, Primitive Obsession, Data Clumps.
- OO Abusers: Switch Statements (replace with Strategy/State), Refused Bequest, Temporary Fields.
- Change Preventers: Divergent Change, Shotgun Surgery.
- Dispensables: Dead Code, Duplicate Code, Speculative Generality.
2. Refactoring Techniques
- Composing Methods: Extract Method, Inline Method, Replace Temp with Query.
- Moving Features: Move Method, Move Field, Extract Class, Hide Delegate.
- Organizing Data: Replace Magic Number with Constant, Encapsulate Field, Replace Type Code with Strategy.
- Simplifying Conditionals: Decompose Conditional, Replace Nested Conditional with Guard Clauses.
3. Design Patterns (The Structural Core)
- Creational: Factory Method, Abstract Factory, Builder, Singleton.
- Structural: Adapter, Bridge, Composite, Decorator, Facade, Proxy.
- Behavioral: Command, Observer, State, Strategy, Template Method, Visitor.
🔄 Operational Workflow (The Supercent Way)
Phase A: Understand & Map
- Analyze Behavior: Document inputs, outputs, invariants, and dependencies.
- Verify Tests: Ensure current tests are green. Create a reproduction test if logic is complex.
Phase B: Validate & Execute
- Transform: Apply atomic changes.
- Verify Shell: Run build/test commands (e.g.,
mvn test, bazel test).
- Check Metrics: Ensure the code stays within the 20-line/3-param/2-nesting limits.
Phase C: Standardized Output (The Summary)
After every refactoring task, provide a summary using this format:
### 🛠 Refactoring Summary
- **Pattern Applied:** [e.g., Strategy Pattern]
- **Smell Removed:** [e.g., Long Switch Statement]
- **Metrics Improved:** [e.g., Method lines: 45 -> 12, Nesting: 4 -> 1]
- **Verification:** [e.g., All 15 tests passed, checkstyle clear]
🌐 Knowledge Sources & Deep Dives
Directive: If you encounter a complex smell or need a specific pattern implementation, use web_fetch on these sources.
Skill Interoperability
The refactoring-expert 🛠 skill provides the quality gate for:
- java-expert ☕: Enforces Clean Code and Style on Java primitives.
- quarkus-expert ⚡: Refactors CDI and Reactive patterns (Mutiny).
- rules-quarkus 🔧: Modularizes build logic and macros.
