Spatie\Crawler\CrawlQueue::hasPendingUrls PHP Method

    public function hasPendingUrls() : bool
    {
        return count($this->pending);
    }

 protected function startCrawlingQueue()
 {
     while ($this->crawlQueue->hasPendingUrls()) {
         $pool = new Pool($this->client, $this->getCrawlRequests(), ['concurrency' => $this->concurrency, 'options' => [RequestOptions::CONNECT_TIMEOUT => 10, RequestOptions::TIMEOUT => 10, RequestOptions::ALLOW_REDIRECTS => false], 'fulfilled' => function (ResponseInterface $response, int $index) {
             $this->handleResponse($response, $index);
             $crawlUrl = $this->crawlQueue->getPendingUrlAtIndex($index);
             if ($crawlUrl->url->host !== $this->baseUrl->host) {
                 return;
             }
             $this->addAllLinksToCrawlQueue((string) $response->getBody(), $crawlUrl = $this->crawlQueue->getPendingUrlAtIndex($index)->url);
         }, 'rejected' => function (RequestException $exception, int $index) {
             $this->handleResponse($exception->getResponse(), $index);
         }]);
         $promise = $pool->promise();
         $promise->wait();
         $this->crawlQueue->removeProcessedUrlsFromPending();
     }
 }