code-refactoring

Before (long function) : After (method extraction) : Before (duplication) : After (extract common logic) : Before (long if-else) : After (polymorphism) : Before (many parameters) : After (grouped into object) : Single Responsibility : Fully understand current behavior before refactoring: Cause : Behavior change occurred Solution : Revert and isolate the change, then retry Cause : Multiple responsibilities mixed in one function Solution : Extract into smaller units with clear boundaries Cause : Inefficient abstraction introduced Solution : Profile and optimize the hot path #refactoring #code-quality #DRY #SOLID #design-patterns #clean-code - Code review : Discovering complex or duplicated code - Before adding new features : Cleaning up existing code - After bug fixes : Removing root causes - Resolving technical debt : Regular refactoring - Test first : Write tests before refactoring - Small steps : Change one thing at a time - Behavior preservation : No functional changes - Multiple tasks simultaneously : No refactoring + feature addition at the same time - Refactoring without tests : Risk of regression - Boy Scout Rule : Leave code cleaner than you found it - Refactoring timing : Red-Green-Refactor (TDD) - Incremental improvement : Consistency over perfection - Behavior preservation : Refactoring involves no functional changes - Small commits : Commit in focused units - Round...