Array Diff Multidimensional Laravel Package

Getting Started

Minimal Setup

1. Installation

   composer require rogervila/array-diff-multidimensional
   

   No additional configuration is required—just autoload the package.

2. Basic Usage

   use Rogervila\ArrayDiffMultidimensional\ArrayDiff;
   
   $array1 = ['a' => 1, 'b' => ['x' => 10, 'y' => 20]];
   $array2 = ['a' => 1, 'b' => ['x' => 10, 'y' => 30]];
   
   $diff = ArrayDiff::diff($array1, $array2);
   // Returns: ['b' => ['y' => 30]]
   

3. First Use Case Compare two nested API responses or database records to identify changes:

   $oldUser = User::find(1)->toArray();
   $newUser = $request->validate()->merge($oldUser)->toArray();
   $changes = ArrayDiff::diff($oldUser, $newUser);
   

Implementation Patterns

Common Workflows

1. Change Detection in Laravel Use with Eloquent models to track field changes:

   $original = $model->getOriginal();
   $changes = ArrayDiff::diff($original, $model->toArray());
   

2. Deep Merging with Conditional Logic Combine with array_merge_recursive to preserve unchanged values:

   $merged = array_merge_recursive(
       $array1,
       ArrayDiff::diff($array1, $array2)
   );
   

3. Diff for Form Validation Validate nested form submissions against a base structure:

   $validated = $request->validate(['data' => 'required|array']);
   $diff = ArrayDiff::diff($baseConfig, $validated['data']);
   if (!empty($diff)) {
       throw new \Exception("Invalid nested fields");
   }
   

4. Integration with Laravel Collections Process diffs in bulk:

   $users = User::all();
   $diffs = $users->map(fn ($user) => ArrayDiff::diff(
       $user->getOriginal(),
       $user->toArray()
   ));
   

Performance Tips

• Cache Results: Store diffs in the session or cache for repeated comparisons.
• Limit Depth: Use ArrayDiff::diff($array1, $array2, 3) to restrict recursion depth for large arrays.

Gotchas and Tips

Pitfalls

1. Key Order Sensitivity The package preserves key order from the first array. If order matters, ensure consistency:

   ksort($array1); ksort($array2); // Normalize before diffing
   

2. Non-Array Values Passing non-array inputs throws InvalidArgumentException. Validate inputs:

   if (!is_array($array1) || !is_array($array2)) {
       throw new \InvalidArgumentException("Inputs must be arrays");
   }
   

3. Circular References Infinite recursion occurs with circular references. Use ArrayDiff::diff($array1, $array2, null, true) to detect cycles.

4. Type Juggling Values like 0 (integer) vs. '0' (string) are treated as equal. Use strict comparison if needed:

   $diff = ArrayDiff::diff($array1, $array2, null, false, true); // Strict mode
   

Debugging

• Verbose Output: Enable debug mode for detailed diffs:

  $diff = ArrayDiff::diff($array1, $array2, null, false, false, true);
  

• Log Diffs: Use Laravel’s logging to inspect complex diffs:

  \Log::debug('Array Diff:', ['diff' => $diff]);
  

Extension Points

1. Custom Diff Strategies Override the default comparator:

   ArrayDiff::setComparator(function ($oldVal, $newVal) {
       return $oldVal === $newVal || (is_numeric($oldVal) && is_numeric($newVal));
   });
   

2. Event Hooks Extend with events (e.g., pre/post-diff hooks) via traits or decorators.

3. Laravel Service Provider Bind the diff service for dependency injection:

   $this->app->singleton(ArrayDiff::class, function () {
       return new ArrayDiff();
   });