refactor-ops

Refactor Operations

Comprehensive refactoring skill covering safe transformation patterns, code smell detection, dead code elimination, and test-driven refactoring methodology.

Refactoring Decision Tree

What kind of refactoring do you need?
│
├─ Extracting code into a new unit
│  ├─ A block of statements with a clear purpose
│  │  └─ Extract Function/Method
│  │     Identify inputs (params) and outputs (return value)
│  │
│  ├─ A UI element with its own state or props
│  │  └─ Extract Component (React, Vue, Svelte)
│  │     Move JSX/template + related state into new file
│  │
│  ├─ Reusable stateful logic (not UI)
│  │  └─ Extract Hook / Composable
│  │     React: useCustomHook, Vue: useComposable
│  │
│  ├─ A file has grown beyond 300-500 lines
│  │  └─ Extract Module
│  │     Split by responsibility, create barrel exports
│  │     Watch for circular dependencies
│  │
│  ├─ A class does too many things (SRP violation)
│  │  └─ Extract Class / Service
│  │     One responsibility per class, use dependency injection
│  │
│  └─ Magic numbers, hardcoded strings, env-specific values
│     └─ Extract Configuration
│        Constants file, env vars, feature flags
│
├─ Renaming for clarity
│  ├─ Variable, function, or method
│  │  └─ Rename Symbol
│  │     Update all references (IDE rename or ast-grep)
│  │
│  ├─ File or directory
│  │  └─ Rename File + Update Imports
│  │     git mv to preserve history, update all import paths
│  │
│  └─ Module or package
│     └─ Rename Module + Update All Consumers
│        Search for all import/require references
│        Consider re-exporting from old name temporarily
│
├─ Moving code to a better location
│  ├─ Function/class to a different file
│  │  └─ Move + Re-export from Original
│  │     Leave re-export for one release cycle
│  │
│  ├─ Files to a different directory
│  │  └─ Restructure + Update All Paths
│  │     Use IDE refactoring or find-and-replace
│  │
│  └─ Reorganize entire directory structure
│     └─ Incremental Migration
│        Move one module at a time, keep tests green
│
├─ Simplifying existing code
│  ├─ Function is too simple to justify its own name
│  │  └─ Inline Function
│  │     Replace call sites with the body
│  │
│  ├─ Variable used only once, right after assignment
│  │  └─ Inline Variable
│  │     Replace variable with expression
│  │
│  ├─ Deep nesting (> 3 levels)
│  │  └─ Guard Clauses + Early Returns
│  │     Invert conditions, return early
│  │
│  └─ Complex conditionals
│     └─ Decompose Conditional
│        Extract each branch into named function
│
└─ Removing dead code
   ├─ Unused imports
   │  └─ Lint + Auto-fix (eslint, ruff, goimports)
   │
   ├─ Unreachable code branches
   │  └─ Static analysis + manual review
   │
   ├─ Orphaned files (no imports point to them)
   │  └─ Dependency graph analysis (knip, ts-prune, vulture)
   │
   └─ Unused exports
      └─ ts-prune, knip, or manual grep for import references