fix casting

Author: taylorotwell

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

@@ -1364,9 +1364,12 @@ public function originalIsEquivalent($key)
         } elseif ($this->isDateAttribute($key)) {
             return $this->fromDateTime($attribute) ===
                    $this->fromDateTime($original);
-        } elseif ($this->hasCast($key, static::$primitiveCastTypes)) {
+        } elseif ($this->hasCast($key, ['object', 'collection'])) {
             return $this->castAttribute($key, $attribute) ==
                 $this->castAttribute($key, $original);
+        } elseif ($this->hasCast($key, static::$primitiveCastTypes)) {
+            return $this->castAttribute($key, $attribute) ===
+                   $this->castAttribute($key, $original);
         }
 
         return is_numeric($attribute) && is_numeric($original)