public function prefixFieldNameReturnsEmptyStringIfGivenFieldNameIsNULL()
{
$viewHelper = $this->getAccessibleMock(\Neos\FluidAdaptor\ViewHelpers\Form\AbstractFormViewHelper::class, array('dummy'), array(), '', false);
$this->injectDependenciesIntoViewHelper($viewHelper);
$this->assertSame('', $viewHelper->_call('prefixFieldName', null));
}