Merge branch 'feature/deviable-casts' into 8.x

src/Illuminate/Contracts/Database/Eloquent/DeviatesCastableAttributes.php

@@ -0,0 +1,28 @@
+<?php
+
+namespace Illuminate\Contracts\Database\Eloquent;
+
+interface DeviatesCastableAttributes
+{
+    /**
+     * Increment the attribute.
+     *
+     * @param  \Illuminate\Database\Eloquent\Model  $model
+     * @param  string  $key
+     * @param  mixed  $value
+     * @param  array  $attributes
+     * @return mixed
+     */
+    public function increment($model, string $key, $value, array $attributes);
+
+    /**
+     * Decrement the attribute.
+     *
+     * @param  \Illuminate\Database\Eloquent\Model  $model
+     * @param  string  $key
+     * @param  mixed  $value
+     * @param  array  $attributes
+     * @return mixed
+     */
+    public function decrement($model, string $key, $value, array $attributes);
+}

src/Illuminate/Database/Eloquent/Concerns/HasAttributes.php

@@ -623,6 +623,21 @@ protected function getCastType($key)
         return trim(strtolower($this->getCasts()[$key]));
     }
 
+    /**
+     * Increment or decrement the given attribute using the custom cast class.
+     *
+     * @param  string  $method
+     * @param  string  $key
+     * @param  mixed  $value
+     * @return mixed
+     */
+    protected function deviateClassCastableAttribute($method, $key, $value)
+    {
+        return $this->resolveCasterClass($key)->{$method}(
+            $this, $key, $value, $this->attributes
+        );
+    }
+
     /**
      * Serialize the given attribute using the custom cast class.
      *
@@ -1162,6 +1177,21 @@ protected function isClassCastable($key)
         throw new InvalidCastException($this->getModel(), $key, $castType);
     }
 
+    /**
+     * Determine if the key is deviable using a custom class.
+     *
+     * @param  string  $key
+     * @return bool
+     *
+     * @throws \Illuminate\Database\Eloquent\InvalidCastException
+     */
+    protected function isClassDeviable($key)
+    {
+        return $this->isClassCastable($key) &&
+            method_exists($castType = $this->parseCasterClass($this->getCasts()[$key]), 'increment') &&
+            method_exists($castType, 'decrement');
+    }
+
     /**
      * Determine if the key is serializable using a custom class.
      *

src/Illuminate/Database/Eloquent/Model.php

@@ -620,7 +620,9 @@ protected function incrementOrDecrement($column, $amount, $extra, $method)
             return $query->{$method}($column, $amount, $extra);
         }
 
-        $this->{$column} = $this->{$column} + ($method === 'increment' ? $amount : $amount * -1);
+        $this->{$column} = $this->isClassDeviable($column)
+            ? $this->deviateClassCastableAttribute($method, $column, $amount)
+            : $this->{$column} + ($method === 'increment' ? $amount : $amount * -1);
 
         $this->forceFill($extra);
 

tests/Integration/Database/DatabaseEloquentModelCustomCastingTest.php

@@ -5,16 +5,30 @@
 use Illuminate\Contracts\Database\Eloquent\Castable;
 use Illuminate\Contracts\Database\Eloquent\CastsAttributes;
 use Illuminate\Contracts\Database\Eloquent\CastsInboundAttributes;
+use Illuminate\Contracts\Database\Eloquent\DeviatesCastableAttributes;
 use Illuminate\Contracts\Database\Eloquent\SerializesCastableAttributes;
 use Illuminate\Database\Eloquent\InvalidCastException;
 use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Schema\Blueprint;
 use Illuminate\Support\Carbon;
+use Illuminate\Support\Facades\Schema;
 
 /**
  * @group integration
  */
 class DatabaseEloquentModelCustomCastingTest extends DatabaseTestCase
 {
+    protected function setUp(): void
+    {
+        parent::setUp();
+
+        Schema::create('test_eloquent_model_with_custom_casts', function (Blueprint $table) {
+            $table->increments('id');
+            $table->timestamps();
+            $table->decimal('price');
+        });
+    }
+
     public function testBasicCustomCasting()
     {
         $model = new TestEloquentModelWithCustomCast;
@@ -135,6 +149,21 @@ public function testGetOriginalWithCastValueObjects()
         $this->assertNull($model->address);
     }
 
+    public function testDeviableCasts()
+    {
+        $model = new TestEloquentModelWithCustomCast;
+        $model->price = '123.456';
+        $model->save();
+
+        $model->increment('price', '530.865');
+
+        $this->assertSame((new Decimal('654.321'))->getValue(), $model->price->getValue());
+
+        $model->decrement('price', '333.333');
+
+        $this->assertSame((new Decimal('320.988'))->getValue(), $model->price->getValue());
+    }
+
     public function testSerializableCasts()
     {
         $model = new TestEloquentModelWithCustomCast;
@@ -326,7 +355,7 @@ public function set($model, $key, $value, $attributes)
     }
 }
 
-class DecimalCaster implements CastsAttributes, SerializesCastableAttributes
+class DecimalCaster implements CastsAttributes, DeviatesCastableAttributes, SerializesCastableAttributes
 {
     public function get($model, $key, $value, $attributes)
     {
@@ -338,6 +367,16 @@ public function set($model, $key, $value, $attributes)
         return (string) $value;
     }
 
+    public function increment($model, $key, $value, $attributes)
+    {
+        return new Decimal($attributes[$key] + $value);
+    }
+
+    public function decrement($model, $key, $value, $attributes)
+    {
+        return new Decimal($attributes[$key] - $value);
+    }
+
     public function serialize($model, $key, $value, $attributes)
     {
         return (string) $value;