refactor

# Fowler/Martin Code Refactoring Best Practices Comprehensive code refactoring guide based on Martin Fowler's catalog and Clean Code principles, designed for AI agents and LLMs. Contains 43 rules across 8 categories, prioritized by impact to guide automated refactoring and code generation. ## When to Apply Reference these guidelines when: - Refactoring existing code to improve maintainability - Decomposing long methods or large classes - Reducing coupling between components - Simplifying complex conditional logic - Reviewing code for code smells and anti-patterns ## Rule Categories by Priority | Priority | Category | Impact | Prefix | |----------|----------|--------|--------| | 1 | Structure & Decomposition | CRITICAL | `struct-` | | 2 | Coupling & Dependencies | CRITICAL | `couple-` | | 3 | Naming & Clarity | HIGH | `name-` | | 4 | Conditional Logic | HIGH | `cond-` | | 5 | Abstraction & Patterns | MEDIUM-HIGH | `pattern-` | | 6 | Data Organization | MEDIUM | `data-` | | 7 | Error Handling | MEDIUM | `error-` | | 8 | Micro-Refactoring | LOW | `micro-` | ## Quick Reference ### 1. Structure & Decomposition (CRITICAL) - `struct-extract-method` - Extract Method for Long Functions - `struct-single-responsibility` - Apply Single Responsibility Principle - `struct-extract-class` - Extract Class from Large Class - `struct-compose-method` - Compose Method for Readable Flow - `struct-function-length` - Keep Functions Under 20 Lines - `struct-replace-method-with-object` - Replace Method with Method Object - `struct-parameter-object` - Introduce Parameter Object ### 2. Coupling & Dependencies (CRITICAL) - `couple-dependency-injection` - Use Dependency Injection - `couple-hide-delegate` - Hide Delegate to Reduce Coupling - `couple-remove-middle-man` - Remove Middle Man When Excessive - `couple-feature-envy` - Fix Feature Envy by Moving Methods - `couple-interface-segregation` - Apply Interface Segregation Principle - `couple-preserve-whole-object` - Preserve Whole Object Instead of Fields ### 3. Naming & Clarity (HIGH) - `name-intention-revealing` - Use Intention-Revealing Names - `name-avoid-abbreviations` - Avoid Abbreviations and Acronyms - `name-consistent-vocabulary` - Use Consistent Vocabulary - `name-searchable-names` - Use Searchable Names - `name-avoid-encodings` - Avoid Type Encodings in Names ### 4. Conditional Logic (HIGH) - `cond-guard-clauses` - Replace Nested Conditionals with Guard Clauses - `cond-polymorphism` - Replace Conditional with Polymorphism - `cond-decompose` - Decompose Complex Conditionals - `cond-consolidate` - Consolidate Duplicate Conditional Fragments - `cond-special-case` - Introduce Special Case Object - `cond-lookup-table` - Replace Conditional with Lookup Table ### 5. Abstraction & Patterns (MEDIUM-HIGH) - `pattern-strategy` - Extract Strategy for Algorithm Variants - `pattern-template-method` - Use Template Method for Shared Skeleton - `pattern-factory` - Use Factory for Complex Object Creation - `pattern-open-closed` - Apply Open-Closed Principle - `pattern-composition-over-inheritance` - Prefer Composition Over Inheritance - `pattern-extract-superclass` - Extract Superclass for Common Behavior ### 6. Data Organization (MEDIUM) - `data-encapsulate-collection` - Encapsulate Collection - `data-replace-primitive` - Replace Primitive with Object - `data-encapsulate-record` - Encapsulate Record into Class - `data-split-variable` - Split Variable with Multiple Assignments - `data-replace-temp-with-query` - Replace Temp with Query ### 7. Error Handling (MEDIUM) - `error-exceptions-over-codes` - Use Exceptions Instead of Error Codes - `error-custom-exceptions` - Create Domain-Specific Exception Types - `error-fail-fast` - Fail Fast with Preconditions - `error-separate-concerns` - Separate Error Handling from Business Logic ### 8. Micro-Refactoring (LOW) - `micro-remove-dead-code` - Remove Dead Code - `micro-inline-variable` - Inline Trivial Variables - `micro-simplify-expressions` - Simplify Boolean Expressions - `micro-rename-for-clarity` - Rename for Clarity ## How to Use Read individual reference files for detailed explanations and code examples: - [Section definitions](references/_sections.md) - Category structure and impact levels - [Rule template](assets/templates/_template.md) - Template for adding new rules - Individual rules: `references/{prefix}-{slug}.md` ## Full Compiled Document For the complete guide with all rules expanded: `AGENTS.md`