/**
  * @param FilterResponseEvent $event
  */
 public function addPjaxVersion(FilterResponseEvent $event)
 {
     $request = $event->getRequest();
     if ($this->pjax->isPjaxRequest($request) && $this->pjax->haveGenerator()) {
         $response = $event->getResponse();
         $response->headers->set('X-PJAX-Version', $this->pjax->generateVersion($request));
     }
 }
 public function test_it_should_add_pjax_version_to_response()
 {
     $event = $this->prophesize('Symfony\\Component\\HttpKernel\\Event\\FilterResponseEvent');
     $response = $this->prophesize('Symfony\\Component\\HttpFoundation\\Response');
     $request = $this->prophesize('\\Symfony\\Component\\HttpFoundation\\Request');
     $headers = $this->prophesize('\\Symfony\\Component\\HttpFoundation\\ResponseHeaderBag');
     $response->headers = $headers->reveal();
     $event->getRequest()->willReturn($request->reveal());
     $event->getResponse()->willReturn($response->reveal());
     $this->pjax->isPjaxRequest($request->reveal())->willReturn(true);
     $this->pjax->haveGenerator()->willReturn(true);
     $this->pjax->generateVersion($request)->willReturn('version');
     $headers->set('X-PJAX-Version', 'version')->shouldBeCalled();
     $this->listener->addPjaxVersion($event->reveal());
 }
 /**
  * @param Request $request
  *
  * @return string|null
  */
 public function pjaxVersion(Request $request)
 {
     $version = $this->pjax->generateVersion($request);
     return $version ? sprintf('<meta http-equiv="x-pjax-version" content="%s"/>', $version) : null;
 }