dev-refactorlisted
Install: claude install-skill christopherlouet/claude-base
# Code Refactoring
## Principles
1. **Tests pass BEFORE and AFTER**
2. **Small incremental changes**
3. **One type of change at a time**
4. **Commit after each refactoring**
## Common techniques
### Extract Function
```typescript
// Before
function processOrder(order) {
// 20 lines of validation
// 30 lines of calculation
// 10 lines of sending
}
// After
function processOrder(order) {
validateOrder(order);
const total = calculateTotal(order);
sendConfirmation(order, total);
}
```
### Extract Variable
```typescript
// Before
if (user.age >= 18 && user.country === 'FR' && !user.banned) { }
// After
const isAdult = user.age >= 18;
const isFrench = user.country === 'FR';
const isActive = !user.banned;
if (isAdult && isFrench && isActive) { }
```
### Replace Conditional with Polymorphism
```typescript
// Before
function getPrice(type) {
switch(type) {
case 'basic': return 10;
case 'premium': return 20;
}
}
// After
interface Plan { getPrice(): number }
class BasicPlan implements Plan { getPrice() { return 10; } }
class PremiumPlan implements Plan { getPrice() { return 20; } }
```
## Code Smells to detect
| Smell | Refactoring |
|-------|-------------|
| Long method | Extract Method |
| Large class | Extract Class |
| Duplicate code | Extract + Reuse |
| Long parameter list | Parameter Object |
| Feature envy | Move Method |
| Primitive obsession | Value Object |
## Reducing Entropy (Complexity reduction)
### Complexity metrics
| Metric | A