/**
  * @param ViewHelperVariableContainer $viewHelperVariableContainer
  * @param string $formClassName
  * @return DomainObjectInterface|NULL
  */
 protected static function getFormObject($viewHelperVariableContainer, $formClassName = FormViewHelper::class)
 {
     if (true === $viewHelperVariableContainer->exists($formClassName, 'formObject')) {
         return $viewHelperVariableContainer->get($formClassName, 'formObject');
     }
     if (self::ALTERNATE_FORM_VIEWHELPER_CLASSNAME !== $formClassName) {
         return self::getFormObject($viewHelperVariableContainer, self::ALTERNATE_FORM_VIEWHELPER_CLASSNAME);
     }
     return null;
 }
 /**
  * @test
  */
 public function addOrUpdateWorks()
 {
     $this->viewHelperVariableContainer->add('TYPO3\\CMS\\Fluid\\ViewHelper\\NonExistent', 'nonExistentKey', 'value1');
     $this->viewHelperVariableContainer->addOrUpdate('TYPO3\\CMS\\Fluid\\ViewHelper\\NonExistent', 'nonExistentKey', 'value2');
     $this->assertEquals($this->viewHelperVariableContainer->get('TYPO3\\CMS\\Fluid\\ViewHelper\\NonExistent', 'nonExistentKey'), 'value2');
 }
 /**
  * @param ViewHelperVariableContainer $viewHelperVariableContainer
  * @param string $formClassName
  * @return DomainObjectInterface|NULL
  */
 protected static function getFormObject($viewHelperVariableContainer, $formClassName = 'Tx_Fluid_ViewHelpers_FormViewHelper')
 {
     if (TRUE === $viewHelperVariableContainer->exists($formClassName, 'formObject')) {
         return $viewHelperVariableContainer->get($formClassName, 'formObject');
     }
     if (self::ALTERNATE_FORM_VIEWHELPER_CLASSNAME !== $formClassName) {
         return self::getFormObject($viewHelperVariableContainer, self::ALTERNATE_FORM_VIEWHELPER_CLASSNAME);
     }
     return NULL;
 }