Method crawl

scrapy/core/engine.py:433–438

Inject the request into the spider <-> downloader pipeline

(self, request: Request)

        return not self._slot.scheduler.has_pending_requests()

    def crawl(self, request: Request) -> None:
        """Inject the request into the spider <-> downloader pipeline"""
        if self.spider is None:
            raise RuntimeError(f"No open spider to crawl: {request}")
        self._schedule_request(request)
        self._slot.nextcall.schedule()  # type: ignore[union-attr]

    def _schedule_request(self, request: Request) -> None:
        request_scheduled_result = self.signals.send_catch_log(