laravel-iterating-on-code

What this skill does

# Iterating on Code

AI-generated code rarely perfect on first try. Effective iteration gets you from "close" to "exactly right."

## Incorrect Code

### Vague Feedback

"This doesn't work"

### Specific Feedback

"The validation is incorrect:

**Current code:**

```php
'email' => 'required|email|unique:users'
```

**Problem:** This allows updating a user's email to another user's existing email. The unique rule needs to ignore the current user.

**Fix:**

```php
'email' => [
    'required',
    'email',
    Rule::unique('users')->ignore($this->user()->id)
]
```

This allows the user to keep their own email but prevents duplicates with other users."

**Why it works:** Identifies the specific problem, explains why it's wrong, shows the correct solution.

## Incomplete Code

### Vague

"Something's missing"

### Specific

"The OrderService is missing error handling:

**Current implementation:**

```php
public function createOrder(array $data): Order
{
    $order = Order::create($data);
    $this->processPayment($order);
    return $order;
}
```

**Missing:**

1. Transaction wrapping (payment and order creation should be atomic)
2. Payment failure handling
3. Inventory validation before creating order
4. Event dispatching after successful creation

**Add:**

```php
DB::transaction(function () use ($data) {
    $this->validateInventory($data['items']);
    $order = Order::create($data);
    $this->processPayment($order);
    event(new OrderCreated($order));
    return $order;
});
```

Plus add try/catch for payment failures."

**Why it works:** Lists specific missing pieces with context and shows how to add them.

## Refinement Needed

### Vague

"Make it better"

### Specific

"Refine the query for better performance:

**Current:**

```php
$products = Product::all()->filter(function ($product) {
    return $product->isActive() && $product->inStock();
});
```

**Issues:**

- Loads all products into memory (inefficient for large datasets)
- Filters in PHP instead of database
- Calls methods on each product (N+1 potential)

**Refined:**

```php
$products = Product::query()
    ->where('active', true)
    ->where('stock_quantity', '>', 0)
    ->get();
```

Move filtering to database, use indexed columns, avoid loading unnecessary data."

**Why it works:** Explains what needs refinement and why, shows the improved version.

## Style Issues

### Vague

"Follow our style guide"

### Specific

"Update to match our coding standards:

**Current:**

```php
public function get_user_orders($userId) {
    return Order::where('user_id', $userId)->get();
}
```

**Style issues:**

1. Method name should be camelCase: `getUserOrders`
2. Parameter should be camelCase: `$userId` ✓ (already correct)
3. Missing return type hint
4. Missing docblock for complex queries

**Corrected:**

```php
/**
 * Get all orders for a specific user.
 */
public function getUserOrders(int $userId): Collection
{
    return Order::where('user_id', $userId)->get();
}
```

See our style guide: `docs/coding-standards.md`"

**Why it works:** Points to specific style violations, shows corrections, references the style guide.

## Incremental Validation

### Bad Approach

"Change the validation, add error handling, refactor the service, update the tests, and add logging"

### Good Approach

"Let's iterate step by step:

**Step 1:** Fix the validation issue first

```php
'email' => Rule::unique('users')->ignore($this->user()->id)
```

Let's verify this works before moving on."

_[After validation confirmed working]_

"**Step 2:** Now add error handling for the payment processing

```php
try {
    $this->processPayment($order);
} catch (PaymentException $e) {
    Log::error('Payment failed', ['order' => $order->id]);
    throw new OrderProcessingException('Payment failed', previous: $e);
}
```

Test this before we continue."

**Why it works:** One change at a time, validate each step, build confidence incrementally.

## Feedback Patterns

### Pattern: Point Out + Explain + Show Fix

````
"The relationship is incorrect:

**Current:** `return $this->hasMany(Post::class);`

**Problem:** A User has many Posts, but you're defining this in the Post model. This creates a circular relationship.

**Fix:** Move this to the User model, or if you meant Post belongs to User:
```php
// In Post model
public function user(): BelongsTo
{
    return $this->belongsTo(User::class);
}
```"
````

### Pattern: Missing + Why It Matters + How to Add

````
"Missing authorization check:

**Why it matters:** Any authenticated user can delete any order, not just their own.

**Add this to OrderController@destroy:**
```php
$this->authorize('delete', $order);
````

And create the policy method:

````php
// In OrderPolicy
public function delete(User $user, Order $order): bool
{
    return $user->id === $order->user_id;
}
```"
````

### Pattern: Current + Issues + Improved

````
"Current implementation has issues:

**Current:**
```php
foreach ($orders as $order) {
    $order->load('items', 'customer', 'shipping');
}
````

**Issues:**

- N+1 queries (loads relationships in loop)
- Inefficient for large datasets

**Improved:**

```php
$orders = Order::with(['items', 'customer', 'shipping'])->get();
```

Single query with eager loading."

```

## Quick Reference

Iterate effectively:
- **Be specific** - Point to exact lines, explain exact problems
- **Show, don't just tell** - Provide corrected code
- **Explain why** - Help the AI understand the reasoning
- **One change at a time** - Validate incrementally
- **Reference standards** - Point to style guides, docs, examples

Specific feedback = better iterations = code that fits your needs.
```