public function testOverwriteClasses()
 {
     $container = $this->createContainer();
     $extension = new GuzzleExtension();
     $extension->load($this->getConfigs(), $container);
     $container->setParameter('guzzle.http_client.class', FakeClient::class);
     $container->setParameter('guzzle_bundle.middleware.wsse.class', FakeWsseAuthMiddleware::class);
     $client = $container->get('guzzle.client.test_api', FakeClient::class);
     $this->assertInstanceOf(FakeClient::class, $client);
     $wsse = $container->get('guzzle_bundle.middleware.wsse.test_api');
     $this->assertInstanceOf(FakeWsseAuthMiddleware::class, $wsse);
 }