Fix incorrect behaviour when comparing castable attributes in originalIsEquivalent method

src/Eloquent/DocumentModel.php

@@ -40,6 +40,7 @@
 use function in_array;
 use function is_array;
 use function is_numeric;
+use function is_object;
 use function is_string;
 use function ltrim;
 use function method_exists;
@@ -377,6 +378,10 @@ public function originalIsEquivalent($key)
                 $this->castAttribute($key, $original);
         }
 
+        if ($this->isClassCastable($key)) {
+            return ! is_object($attribute) ? $attribute === $original : $attribute == $original;
+        }
+
         return is_numeric($attribute) && is_numeric($original)
             && strcmp((string) $attribute, (string) $original) === 0;
     }

tests/ModelTest.php

@@ -26,6 +26,7 @@
 use MongoDB\Laravel\Tests\Models\Item;
 use MongoDB\Laravel\Tests\Models\MemberStatus;
 use MongoDB\Laravel\Tests\Models\NonIncrementing;
+use MongoDB\Laravel\Tests\Models\Options;
 use MongoDB\Laravel\Tests\Models\Soft;
 use MongoDB\Laravel\Tests\Models\SqlUser;
 use MongoDB\Laravel\Tests\Models\User;
@@ -1075,6 +1076,22 @@ public function testGetDirtyDates(): void
         $this->assertEmpty($user->getDirty());
     }
 
+    public function testGetDirtyObjects(): void
+    {
+        $user = new User();
+        $user->options = new Options();
+        $this->assertNotEmpty($user->getDirty());
+
+        $user->save();
+        $this->assertEmpty($user->getDirty());
+
+        $user->options = (new Options())->setOption1('Value1');
+        $this->assertNotEmpty($user->getDirty());
+
+        $user->save();
+        $this->assertEmpty($user->getDirty());
+    }
+
     public function testChunkById(): void
     {
         User::create(['name' => 'fork', 'tags' => ['sharp', 'pointy']]);

tests/Models/Options.php

@@ -0,0 +1,37 @@
+<?php
+
+declare(strict_types=1);
+
+namespace MongoDB\Laravel\Tests\Models;
+
+class Options
+{
+    private string $option1;
+    private string $option2;
+
+    public function setOption1(string $option1): self
+    {
+        $this->option1 = $option1;
+        return $this;
+    }
+
+    public function setOption2(string $option2): self
+    {
+        $this->option2 = $option2;
+        return $this;
+    }
+
+    public function serialize(): object
+    {
+        $result = [];
+        if (isset($this->option1)) {
+            $result['option1'] = $this->option1;
+        }
+
+        if (isset($this->option2)) {
+            $result['option2'] = $this->option2;
+        }
+
+        return (object) $result;
+    }
+}

tests/Models/OptionsCast.php

@@ -0,0 +1,40 @@
+<?php
+
+declare(strict_types=1);
+
+namespace MongoDB\Laravel\Tests\Models;
+
+use Illuminate\Contracts\Database\Eloquent\CastsAttributes;
+use Illuminate\Database\Eloquent\Model;
+
+class OptionsCast implements CastsAttributes
+{
+    public function get(Model $model, string $key, mixed $value, array $attributes): Options
+    {
+        $attributes = new Options();
+        if (! empty($value['option1'])) {
+            $attributes->setOption1($value['option1']);
+        }
+
+        if (! empty($value['option2'])) {
+            $attributes->setOption2($value['option2']);
+        }
+
+        return $attributes;
+    }
+
+    /**
+     * @param Model        $model
+     * @param string       $key
+     * @param Options|null $value
+     * @param array        $attributes
+     *
+     * @return null[]|object[]
+     */
+    public function set(Model $model, string $key, mixed $value, array $attributes): array
+    {
+        return [
+            $key => $value?->serialize(),
+        ];
+    }
+}

tests/Models/User.php

@@ -29,6 +29,7 @@
  * @property Carbon $updated_at
  * @property string $username
  * @property MemberStatus member_status
+ * @property Options $options
  */
 class User extends Model implements AuthenticatableContract, CanResetPasswordContract
 {
@@ -44,6 +45,7 @@ class User extends Model implements AuthenticatableContract, CanResetPasswordCon
         'birthday' => 'datetime',
         'entry.date' => 'datetime',
         'member_status' => MemberStatus::class,
+        'options' => OptionsCast::class,
     ];
 
     protected $fillable = [