Fix typing issues for typed Scrapy. (#166)

scrapy_poet/downloadermiddlewares.py

@@ -99,6 +99,7 @@ def process_request(
             return None
 
         logger.debug(f"Using DummyResponse instead of downloading {request}")
+        assert self.crawler.stats
         self.crawler.stats.inc_value("scrapy_poet/dummy_response_count")
         return DummyResponse(url=request.url, request=request)
 
@@ -132,7 +133,7 @@ def _skip_dependency_creation(self, request: Request, spider: Spider) -> bool:
     @inlineCallbacks
     def process_response(
         self, request: Request, response: Response, spider: Spider
-    ) -> Generator[Deferred, object, Response]:
+    ) -> Generator[Deferred, object, Union[Response, Request]]:
         """This method fills :attr:`scrapy.Request.cb_kwargs
         <scrapy.http.Request.cb_kwargs>` with instances for the required Page
         Objects found in the callback signature.

scrapy_poet/injection.py

@@ -272,6 +272,7 @@ def build_instances(
         )
         # All the remaining dependencies are internal so they can be built just
         # following the andi plan.
+        assert self.crawler.stats
         for cls, kwargs_spec in plan.dependencies:
             if cls not in instances.keys():
                 result_cls: type = cast(type, cls)
@@ -295,6 +296,7 @@ def build_instances_from_providers(
         plan: andi.Plan,
     ):
         """Build dependencies handled by registered providers"""
+        assert self.crawler.stats
         instances: Dict[Callable, Any] = {}
         scrapy_provided_dependencies = self.available_dependencies_for_providers(
             request, response
@@ -320,7 +322,7 @@ def build_instances_from_providers(
                     )
                 # This one should take `web_poet.HttpRequest` but `scrapy.Request` will work as well
                 # TODO: add `scrapy.Request` type in request_fingerprint() annotations
-                fingerprint = f"{provider.name}_{request_fingerprint(request)}"
+                fingerprint = f"{provider.name}_{request_fingerprint(request)}"  # type: ignore[arg-type]
                 # Return the data if it is already in the cache
                 try:
                     data = self.cache[fingerprint].items()

scrapy_poet/page_input_providers.py

@@ -189,6 +189,7 @@ def __call__(self, to_provide: Set[Callable], crawler: Crawler):
         <web_poet.page_inputs.client.HttpClient>` instance using Scrapy's
         downloader.
         """
+        assert crawler.engine
         downloader = create_scrapy_downloader(crawler.engine.download)
         save_responses = crawler.settings.getbool("_SCRAPY_POET_SAVEFIXTURE")
         return [

scrapy_poet/spidermiddlewares.py

@@ -21,6 +21,7 @@ def process_spider_exception(
 
         if not isinstance(exception, Retry):
             return None
+        assert response.request
         new_request_or_none = get_retry_request(
             response.request,
             spider=spider,

scrapy_poet/utils/__init__.py

@@ -20,8 +20,7 @@
 try:
     from scrapy.http.request import NO_CALLBACK  # available on Scrapy >= 2.8
 except ImportError:
-    # NO_CALLBACK = lambda: None  # noqa: E731
-    NO_CALLBACK = None
+    NO_CALLBACK = None  # type: ignore[assignment]
 
 
 def get_scrapy_data_path(createdir: bool = True, default_dir: str = ".scrapy") -> str:

scrapy_poet/utils/testing.py

@@ -1,7 +1,6 @@
 import json
 from inspect import isasyncgenfunction
 from typing import Dict
-from unittest import mock
 
 from scrapy import Spider, signals
 from scrapy.crawler import Crawler
@@ -272,10 +271,3 @@ async def parse(*args, **kwargs):
     # Mimic type annotations
     parse.__annotations__ = callback.__annotations__
     return parse
-
-
-class AsyncMock(mock.MagicMock):
-    """workaround since python 3.7 doesn't ship with asyncmock."""
-
-    async def __call__(self, *args, **kwargs):
-        return super().__call__(*args, **kwargs)

tests/test_downloader.py

@@ -29,7 +29,6 @@
 )
 from scrapy_poet.utils.mockserver import MockServer
 from scrapy_poet.utils.testing import (
-    AsyncMock,
     DelayedResource,
     EchoResource,
     StatusResource,
@@ -40,7 +39,7 @@
 
 @pytest.fixture
 def scrapy_downloader() -> Callable:
-    mock_downloader = AsyncMock()
+    mock_downloader = mock.AsyncMock()
     return create_scrapy_downloader(mock_downloader)
 
 
@@ -69,12 +68,12 @@ async def test_scrapy_poet_downloader(fake_http_response) -> None:
     req = web_poet.HttpRequest("https://example.com")
 
     with mock.patch(
-        "scrapy_poet.downloader.maybe_deferred_to_future", new_callable=AsyncMock
+        "scrapy_poet.downloader.maybe_deferred_to_future", new_callable=mock.AsyncMock
     ) as mock_dtf:
 
         mock_dtf.return_value = fake_http_response
 
-        mock_downloader = mock.MagicMock(return_value=AsyncMock)
+        mock_downloader = mock.MagicMock(return_value=mock.AsyncMock)
         scrapy_downloader = create_scrapy_downloader(mock_downloader)
 
         response = await scrapy_downloader(req)
@@ -96,10 +95,10 @@ async def test_scrapy_poet_downloader_ignored_request() -> None:
     req = web_poet.HttpRequest("https://example.com")
 
     with mock.patch(
-        "scrapy_poet.downloader.maybe_deferred_to_future", new_callable=AsyncMock
+        "scrapy_poet.downloader.maybe_deferred_to_future", new_callable=mock.AsyncMock
     ) as mock_dtf:
         mock_dtf.side_effect = scrapy.exceptions.IgnoreRequest
-        mock_downloader = mock.MagicMock(return_value=AsyncMock)
+        mock_downloader = mock.MagicMock(return_value=mock.AsyncMock)
         scrapy_downloader = create_scrapy_downloader(mock_downloader)
 
         with pytest.raises(web_poet.exceptions.HttpError):
@@ -111,10 +110,10 @@ async def test_scrapy_poet_downloader_twisted_error() -> None:
     req = web_poet.HttpRequest("https://example.com")
 
     with mock.patch(
-        "scrapy_poet.downloader.maybe_deferred_to_future", new_callable=AsyncMock
+        "scrapy_poet.downloader.maybe_deferred_to_future", new_callable=mock.AsyncMock
     ) as mock_dtf:
         mock_dtf.side_effect = twisted.internet.error.TimeoutError
-        mock_downloader = mock.MagicMock(return_value=AsyncMock)
+        mock_downloader = mock.MagicMock(return_value=mock.AsyncMock)
         scrapy_downloader = create_scrapy_downloader(mock_downloader)
 
         with pytest.raises(web_poet.exceptions.HttpRequestError):
@@ -126,10 +125,10 @@ async def test_scrapy_poet_downloader_head_redirect(fake_http_response) -> None:
     req = web_poet.HttpRequest("https://example.com", method="HEAD")
 
     with mock.patch(
-        "scrapy_poet.downloader.maybe_deferred_to_future", new_callable=AsyncMock
+        "scrapy_poet.downloader.maybe_deferred_to_future", new_callable=mock.AsyncMock
     ) as mock_dtf:
         mock_dtf.return_value = fake_http_response
-        mock_downloader = mock.MagicMock(return_value=AsyncMock)
+        mock_downloader = mock.MagicMock(return_value=mock.AsyncMock)
         scrapy_downloader = create_scrapy_downloader(mock_downloader)
 
         await scrapy_downloader(req)
@@ -454,6 +453,7 @@ async def __call__(
             custom_request = Request(
                 request.url, body=request.body, callback=NO_CALLBACK
             )
+            assert crawler.engine
             scrapy_response: Response = await maybe_deferred_to_future(
                 crawler.engine.download(custom_request)
             )
@@ -493,7 +493,7 @@ class TestSpider(Spider):
             def start_requests(self):
                 yield Request(server.root_url, callback=self.parse)
 
-            async def parse(self, response: DummyResponse, page: ItemPage):
+            async def parse(self, response: DummyResponse, page: ItemPage):  # type: ignore[override]
                 item = await page.to_item()
                 items.append(item)
 
@@ -570,7 +570,7 @@ def test_parse_callback_none_dummy_response() -> None:
         class TestSpider(BaseSpider):
             start_urls = [server.root_url]
 
-            def parse(self, response: DummyResponse):
+            def parse(self, response: DummyResponse):  # type: ignore[override]
                 collected["response"] = response
 
         crawler = make_crawler(TestSpider)
@@ -662,7 +662,7 @@ def test_parse_callback_none_with_deps(caplog) -> None:
         class TestSpider(BaseSpider):
             start_urls = [server.root_url]
 
-            def parse(self, response: DummyResponse, page: BasicPage):
+            def parse(self, response: DummyResponse, page: BasicPage):  # type: ignore[override]
                 pass
 
         crawler = make_crawler(TestSpider)
@@ -705,7 +705,7 @@ def start_requests(self):
                 page = BasicPage(web_poet.HttpResponse("https://example.com", b""))
                 yield Request(server.root_url, cb_kwargs={"page": page})
 
-            def parse(self, response: DummyResponse, page: BasicPage):
+            def parse(self, response: DummyResponse, page: BasicPage):  # type: ignore[override]
                 collected["response"] = response
 
         crawler = make_crawler(TestSpider)
@@ -740,7 +740,7 @@ def start_requests(self):
                 page = BasicPage(web_poet.HttpResponse("https://example.com", b""))
                 yield Request(server.root_url, cb_kwargs={"page": page})
 
-            def parse(
+            def parse(  # type: ignore[override]
                 self,
                 response: DummyResponse,
                 page: BasicPage,
@@ -782,7 +782,7 @@ def test_parse_callback_NO_CALLBACK(caplog) -> None:
         class TestSpider(BaseSpider):
             start_urls = [server.root_url]
 
-            def parse(self, response: DummyResponse):
+            def parse(self, response: DummyResponse):  # type: ignore[override]
                 collected["response"] = response
 
         crawler = make_crawler(TestSpider)
@@ -814,7 +814,7 @@ def test_parse_callback_NO_CALLBACK_with_page_dep(caplog) -> None:
         class TestSpider(BaseSpider):
             start_urls = [server.root_url]
 
-            def parse(self, response: DummyResponse, page: BasicPage):
+            def parse(self, response: DummyResponse, page: BasicPage):  # type: ignore[override]
                 collected["response"] = response
 
         crawler = make_crawler(TestSpider)

tests/test_injection.py

@@ -302,6 +302,7 @@ def _assert_instances(
         reqmeta: Optional[Dict[str, Any]] = None,
     ) -> Generator[Any, Any, None]:
         response = get_response_for_testing(callback, meta=reqmeta)
+        assert response.request
         request = response.request
 
         plan = injector.build_plan(response.request)

tests/test_middleware.py

@@ -301,7 +301,7 @@ class SkipDownloadSpider(scrapy.Spider):
     def start_requests(self):
         yield Request(url=self.url, callback=self.parse)
 
-    def parse(self, response: DummyResponse):
+    def parse(self, response: DummyResponse):  # type: ignore[override]
         return {
             "response": response,
         }
@@ -332,7 +332,7 @@ class RequestUrlSpider(scrapy.Spider):
     def start_requests(self):
         yield Request(url=self.url, callback=self.parse)
 
-    def parse(self, response: DummyResponse, url: RequestUrl):
+    def parse(self, response: DummyResponse, url: RequestUrl):  # type: ignore[override]
         return {
             "response": response,
             "url": url,
@@ -359,7 +359,7 @@ class ResponseUrlSpider(scrapy.Spider):
     def start_requests(self):
         yield Request(url=self.url, callback=self.parse)
 
-    def parse(self, response: DummyResponse, url: ResponseUrl):
+    def parse(self, response: DummyResponse, url: ResponseUrl):  # type: ignore[override]
         return {
             "response": response,
             "url": url,
@@ -396,7 +396,7 @@ class ResponseUrlPageSpider(scrapy.Spider):
     def start_requests(self):
         yield Request(url=self.url, callback=self.parse)
 
-    def parse(self, response: DummyResponse, page: ResponseUrlPage):
+    def parse(self, response: DummyResponse, page: ResponseUrlPage):  # type: ignore[override]
         return page.to_item()
 
 
@@ -427,7 +427,7 @@ class RequestUrlPageSpider(scrapy.Spider):
     def start_requests(self):
         yield Request(url=self.url, callback=self.parse)
 
-    def parse(self, response: DummyResponse, page: RequestUrlPage):
+    def parse(self, response: DummyResponse, page: RequestUrlPage):  # type: ignore[override]
         return page.to_item()
 
 

tests/test_providers.py

@@ -30,12 +30,7 @@
     StatsProvider,
 )
 from scrapy_poet.utils.mockserver import get_ephemeral_port
-from scrapy_poet.utils.testing import (
-    AsyncMock,
-    HtmlResource,
-    ProductHtml,
-    crawl_single_item,
-)
+from scrapy_poet.utils.testing import HtmlResource, ProductHtml, crawl_single_item
 
 
 class NonProductHtml(HtmlResource):
@@ -75,7 +70,9 @@ def __call__(
         assert isinstance(spider, scrapy.Spider)
         ret: List[Any] = []
         if Price in to_provide:
-            ret.append(Price(response.css(".price::text").get()))
+            price = response.css(".price::text").get()
+            assert price is not None
+            ret.append(Price(price))
         if Html in to_provide:
             ret.append(Html("Price Html!"))
         return ret
@@ -89,7 +86,9 @@ def __call__(self, to_provide, response: scrapy.http.Response, settings: Setting
         assert isinstance(settings, Settings)
         ret: List[Any] = []
         if Name in to_provide:
-            ret.append(Name(response.css(".name::text").get()))
+            name = response.css(".name::text").get()
+            assert name is not None
+            ret.append(Name(name))
         if Html in to_provide:
             ret.append(Html("Name Html!"))
         return ret
@@ -200,7 +199,7 @@ def test_price_first_spider(settings):
 @ensureDeferred
 async def test_http_client_provider(settings):
     crawler = get_crawler(Spider, settings)
-    crawler.engine = AsyncMock()
+    crawler.engine = mock.AsyncMock()
     injector = Injector(crawler)
 
     with mock.patch(

tests/test_response_required_logic.py

@@ -22,13 +22,7 @@
     HttpResponseProvider,
     PageObjectInputProvider,
 )
-from scrapy_poet.utils import is_min_scrapy_version
-
-# See: https://github.com/scrapinghub/scrapy-poet/issues/118
-try:
-    from scrapy.http.request import NO_CALLBACK  # available on Scrapy >= 2.8
-except ImportError:
-    NO_CALLBACK = lambda: None  # noqa: E731
+from scrapy_poet.utils import NO_CALLBACK, is_min_scrapy_version
 
 
 @attr.s(auto_attribs=True)
@@ -70,13 +64,13 @@ def __call__(self, to_provide):
 class TextProductProvider(HttpResponseProvider):
     # This is wrong. You should not annotate provider dependencies with classes
     # like TextResponse or HtmlResponse, you should use Response instead.
-    def __call__(self, to_provide, response: TextResponse):
+    def __call__(self, to_provide, response: TextResponse):  # type: ignore[override]
         return super().__call__(to_provide, response)
 
 
 class StringProductProvider(HttpResponseProvider):
-    def __call__(self, to_provide, response: str):
-        return super().__call__(to_provide, response)
+    def __call__(self, to_provide, response: str):  # type: ignore[override]
+        return super().__call__(to_provide, response)  # type: ignore[arg-type]
 
 
 @attr.s(auto_attribs=True)
@@ -224,8 +218,11 @@ def test_is_provider_using_response():
     reason="tests Scrapy < 2.8 before NO_CALLBACK was introduced",
 )
 def test_is_callback_using_response_for_scrapy28_below() -> None:
+    def cb(_: Any) -> Any:
+        return _
+
     spider = MySpider()
-    request = Request("https://example.com", callback=lambda _: _)
+    request = Request("https://example.com", callback=cb)
     assert is_callback_requiring_scrapy_response(spider.parse, request.callback) is True
     assert (
         is_callback_requiring_scrapy_response(spider.parse2, request.callback) is True
@@ -362,8 +359,11 @@ def test_is_callback_using_response_for_scrapy28_below() -> None:
     reason="NO_CALLBACK not available in Scrapy < 2.8",
 )
 def test_is_callback_using_response_for_scrapy28_and_above() -> None:
+    def cb(_: Any) -> Any:
+        return _
+
     spider = MySpider()
-    request_with_callback = Request("https://example.com", callback=lambda _: _)
+    request_with_callback = Request("https://example.com", callback=cb)
     request_no_callback = Request("https://example.com", callback=NO_CALLBACK)
 
     with warnings.catch_warnings(record=True) as caught_warnings:

tox.ini

@@ -79,6 +79,7 @@ deps =
 deps =
     mypy==1.11.2
     pytest
+    Scrapy @ git+https://github.com/scrapy/scrapy@master
 
 commands = mypy --ignore-missing-imports scrapy_poet tests