title: Laravel Eloquent Dirty Checking Carbon Dates
body: <p>I have a <code>published_at</code> field in my model that I setup as a carbon date.</p>
  
  <pre><code>class Model {
  
      protected $dates = ['published_at'];
  
      ....
  
      public function setPublishedAtAttribute($val)
      {
           $this-&gt;attributes['published_at'] = \Carbon\Carbon::createFromTimeStamp(strtotime($val));
      }
  }
  </code></pre>
  
  <p>This is a filed settable by the user. When I run a <code>dirty</code> check on it:</p>
  
  <pre><code>$article-&gt;fill($data);
  echo $article-&gt;isDirty() ? 'true' : 'false';
  </code></pre>
  
  <p>It always comes up <code>dirty</code>. Am I doing something wrong or is this because it's trying to compare two Carbon objects?</p>