/**
  * @param Post $post
  * @param array $mentioned
  */
 protected function sync(Post $post, array $mentioned)
 {
     $post->mentionsUsers()->sync($mentioned);
     $users = User::whereIn('id', $mentioned)->get()->filter(function ($user) use($post) {
         return $post->isVisibleTo($user) && $user->id !== $post->user->id;
     })->all();
     $this->notifications->sync(new UserMentionedBlueprint($post), $users);
 }