/**
  * Should we return the error as JSON?
  *
  * @access  protected
  * @return  boolean
  */
 protected function returnAsJson()
 {
     $acceptableContentTypes = $this->request->acceptableContentTypes();
     return $this->request->isAjax() || isset($acceptableContentTypes[0]) && in_array($acceptableContentTypes[0], ['application/json', 'text/json']);
 }
 /**
  *
  */
 public function testIsAjax()
 {
     $server = $this->getServerData();
     $request = new Request(['server' => $server]);
     $this->assertFalse($request->isAjax());
     //
     $server['HTTP_X_REQUESTED_WITH'] = 'XMLHttpRequest';
     $request = new Request(['server' => $server]);
     $this->assertTrue($request->isAjax());
 }