protected function assertPlaceholder($container, $logic, $negated, $allowEmpty, $modelName = null)
 {
     parent::assertPlaceholder($container, $logic, $negated, $allowEmpty);
     $placeholder = $this->getLastCondition();
     if ($modelName === null) {
         $modelName = $this->modelName;
     }
     $this->assertAttributeSame($modelName, 'currentModelName', $placeholder->container());
 }