Refactoring

Refactoring Basics

Process, Baby Steps

Code Smells

Mysterious Name, Duplicated Code, Long Function, Long Parameter List, Global Data, Mutable Data, Divergent Change, Shotgun Surgery, Feature Envy, Data Clumps, Primitive Obsession, Repeated Switches, Loops, Lazy Element, Speculative Generality, Temporary Field, Message Chains, Middle Man, Insider Trading, Large Class, Data Class, Refused Bequest, Comments

Basic Refactorings

Extract Function/Method, Inline Function/Method, Extract Variable, Inline Variable, Change Function Declaration, Encapsulate Variable, Rename Variable, Introduce Parameter Object, Combine Functions into Class, Combine Functions into Transform, Split Phase

Encapsulation Refactorings

Encapsulate Record, Encapsulate Collection, Replace Primitive with Object, Replace Temp with Query, Extract Class, Inline Class, Hide Delegate, Remove Middle Man, Substitute Algorithm

Moving Features Refactorings

Move Function, Move Field, Move Statements into Function, Move Statements to Callers, Replace Inline Code with Function Call, Slide Statements, Split Loop, Replace Loop with Pipeline, Remove Dead Code

Organizing Data Refactorings

Split Variable, Rename Field, Replace Derived Variable with Query, Change Reference to Value, Change Value to Reference

Conditional Logic Refactorings

Decompose Conditional, Consolidate Conditional Expression, Replace Nested Conditional with Guard Clauses, Replace Conditional with Polymorphism, Introduce Special Case, Introduce Null Object, Introduce Assertion

API Refactorings

Separate Query from Modifier, Parameterize Function, Remove Flag Argument, Preserve Whole Object, Replace Parameter with Query, Replace Query with Parameter, Remove Setting Method, Replace Constructor with Factory Function, Replace Function with Command, Replace Command with Function

Inheritance Refactorings

Pull Up Method, Pull Up Field, Pull Up Constructor Body, Push Down Method, Push Down Field, Replace Type Code with Subclasses, Remove Subclass, Extract Superclass, Collapse Hierarchy, Replace Subclass with Delegate, Replace Superclass with Delegate