Blackfire\Player\Guzzle\StepMiddleware::create PHP Метод

    public static function create(RequestFactory $requestFactory, ExpressionLanguage $language, array $extensions = [], LoggerInterface $logger = null)
    {
        return function (callable $handler) use($requestFactory, $language, $extensions, $logger) {
            return new self($handler, $requestFactory, $language, $extensions, $logger);
        };
    }

 private function registerHandlers()
 {
     if ($this->handlersRegistered) {
         return;
     }
     foreach ($this->clients as $client) {
         $stack = $client->getConfig('handler');
         $stack->unshift(StepMiddleware::create($this->getRequestFactory(), $this->getLanguage(), $this->extensions, $this->logger), 'scenario');
         $stack->push(ExpectationsMiddleware::create($this->getLanguage(), $this->logger), 'expectations');
         foreach ($this->extensions as $extension) {
             $extension->registerHandlers($stack);
         }
     }
     $this->handlersRegistered = true;
 }