Overview
Refactoring fails when it changes behavior while intending to only improve structure, when it replaces one complexity with a different complexity, or when it's done without tests that verify the behavior before and after. A refactoring that passes "looks cleaner" but breaks a downstream consumer has made the code worse, not better. Safe refactoring is test-first, small-step, and behaviorally equivalent.
The Code Refactoring Framework identifies the specific code smell, applies the correct refactoring technique, and verifies behavioral equivalence at each step.
Key Features
Code smell catalog with specific techniques
Extract Method example with before/after
Guard clause replacement flattening nested conditionals
Magic number replacement with named constants