/**
  * Override to add an extra rule for the defaultModelStringifiedName. This will ensure if there is an error
  * the message shows up properly in the user interface, since otherwise with the rule being on the
  * defaultModelId, it would not show up because it is a hidden input.
  * @see DefaultModelAttributeMappingRuleForm::rules()
  */
 public function rules()
 {
     if ($this->getScenario() == 'extraColumn') {
         $requiredRuleIsApplicable = true;
     } else {
         $requiredRuleIsApplicable = false;
     }
     $defaultValueApplicableModelAttributeRules = ModelAttributeRulesToDefaultValueMappingRuleUtil::getApplicableRulesByModelClassNameAndAttributeName($this->modelClassName, $this->modelAttributeName, 'defaultModelStringifiedName', $requiredRuleIsApplicable);
     return array_merge(parent::rules(), $defaultValueApplicableModelAttributeRules);
     return array_merge(parent::rules(), $defaultValueApplicableModelAttributeRules);
 }