/**
  * @covers \ZF\HttpCache\HttpCacheListener::setExpires
  * @dataProvider setExpiresDataProvider
  *
  * @param array $cacheConfig
  * @param array $headers
  * @param array $exHeaders
  */
 public function testSetExpires(array $cacheConfig, array $headers, array $exHeaders)
 {
     $this->instance->setCacheConfig($cacheConfig);
     $response = new HttpResponse();
     $headers = $response->getHeaders()->addHeaders($headers);
     $this->instance->setExpires($headers);
     $headers = $headers->toArray();
     $this->assertArrayHasKey('Expires', $headers);
     $date = new \DateTime($headers['Expires']);
     $exDate = new \DateTime($exHeaders['Expires']);
     $this->assertEquals($exDate, $date, '', 3);
 }