/**
  * Make sure the given response is not successful.
  *
  * @param string $status
  */
 public function isNotSuccessful($status = 'failed')
 {
     $this->assertFalse($this->response->isSuccessful());
     $this->assertFalse($this->response->isRedirect());
     $this->assertSame($status, $this->response->getStatus());
 }