ensure mypy validates tests

tests/po_lib/__init__.py

@@ -1,27 +1,27 @@
 """
 This package is just for overrides testing purposes.
 """
-from typing import Any, Callable, Dict
+from typing import Any, Dict, Type
 
 from url_matcher import Patterns
 
-from web_poet import handle_urls
+from web_poet import ItemPage, handle_urls
 
 # NOTE: this module contains a PO with @handle_rules
 from .. import po_lib_sub  # noqa: F401
 
 
-class POBase:
-    expected_overrides: Callable
+class POBase(ItemPage):
+    expected_overrides: Type[ItemPage]
     expected_patterns: Patterns
     expected_meta: Dict[str, Any]
 
 
-class POTopLevelOverriden1:
+class POTopLevelOverriden1(ItemPage):
     ...
 
 
-class POTopLevelOverriden2:
+class POTopLevelOverriden2(ItemPage):
     ...
 
 

tests/po_lib/a_module.py

@@ -1,10 +1,10 @@
 from url_matcher import Patterns
 
 from tests.po_lib import POBase
-from web_poet import handle_urls
+from web_poet import ItemPage, handle_urls
 
 
-class POModuleOverriden:
+class POModuleOverriden(ItemPage):
     ...
 
 

tests/po_lib/nested_package/__init__.py

@@ -1,10 +1,10 @@
 from url_matcher import Patterns
 
 from tests.po_lib import POBase
-from web_poet import handle_urls
+from web_poet import ItemPage, handle_urls
 
 
-class PONestedPkgOverriden:
+class PONestedPkgOverriden(ItemPage):
     ...
 
 

tests/po_lib/nested_package/a_nested_module.py

@@ -1,10 +1,10 @@
 from url_matcher import Patterns
 
 from tests.po_lib import POBase
-from web_poet import handle_urls
+from web_poet import ItemPage, handle_urls
 
 
-class PONestedModuleOverriden:
+class PONestedModuleOverriden(ItemPage):
     ...
 
 

tests/po_lib_sub/__init__.py

@@ -1,20 +1,20 @@
 """This package is being used by tests/po_lib to validate some behaviors on
 external depedencies.
 """
-from typing import Any, Callable, Dict
+from typing import Any, Dict, Type
 
 from url_matcher import Patterns
 
-from web_poet import handle_urls
+from web_poet import ItemPage, handle_urls
 
 
-class POBase:
-    expected_overrides: Callable
+class POBase(ItemPage):
+    expected_overrides: Type[ItemPage]
     expected_patterns: Patterns
     expected_meta: Dict[str, Any]
 
 
-class POLibSubOverriden:
+class POLibSubOverriden(ItemPage):
     ...
 
 

tests/test_exceptions.py

@@ -6,7 +6,7 @@
 URL = "https://example.com"
 
 
-def test_http_error_init():
+def test_http_error_init() -> None:
     exc = HttpError()
     assert exc.request is None
     assert exc.args
@@ -16,7 +16,7 @@ def test_http_error_init():
     assert exc.request == request
 
 
-def test_http_request_error_init():
+def test_http_request_error_init() -> None:
     exc = HttpRequestError()
     assert exc.request is None
     assert exc.args
@@ -27,10 +27,10 @@ def test_http_request_error_init():
 
     response = HttpResponse(URL, b"")
     with pytest.raises(TypeError):
-        HttpRequestError(request=request, response=response)
+        HttpRequestError(request=request, response=response)  # type: ignore[call-arg]
 
 
-def test_http_response_error_init():
+def test_http_response_error_init() -> None:
     exc = HttpResponseError()
     assert exc.request is None
     assert exc.response is None

tests/test_fields.py

@@ -55,7 +55,7 @@ def unknown_attribute(self):  # noqa: D102
 
 
 @pytest.mark.asyncio
-async def test_fields():
+async def test_fields() -> None:
     page = Page(response=EXAMPLE_RESPONSE)
 
     assert page.name == "Hello!"
@@ -68,15 +68,15 @@ async def test_fields():
 
 
 @pytest.mark.asyncio
-async def test_fields_invalid_page():
+async def test_fields_invalid_page() -> None:
     page = InvalidPage(response=EXAMPLE_RESPONSE)
     with pytest.raises(
         TypeError, match="unexpected keyword argument 'unknown_attribute'"
     ):
         await page.to_item()
 
 
-def test_item_from_fields_sync():
+def test_item_from_fields_sync() -> None:
     @attrs.define
     class Page(ItemPage):
         @field
@@ -90,12 +90,13 @@ def to_item(self):  # noqa: D102
     assert page.to_item() == dict(name="name")
 
 
-def test_field_non_callable():
+def test_field_non_callable() -> None:
     with pytest.raises(TypeError):
 
         @attrs.define
         class Page(ItemPage):
-            @field
+            # https://github.com/python/mypy/issues/1362#issuecomment-438246775
+            @field  # type: ignore
             @property
             def name(self):  # noqa: D102
                 return "name"
@@ -104,7 +105,7 @@ def to_item(self):  # noqa: D102
                 return item_from_fields_sync(self, dict)
 
 
-def test_field_classmethod():
+def test_field_classmethod() -> None:
     with pytest.raises(TypeError):
 
         @attrs.define
@@ -119,7 +120,7 @@ def to_item(self):  # noqa: D102
 
 
 @pytest.mark.asyncio
-async def test_field_order():
+async def test_field_order() -> None:
     class DictItemPage(Page):
         async def to_item(self):
             return await item_from_fields(self)
@@ -130,7 +131,7 @@ async def to_item(self):
     assert list(item.keys()) == ["name", "price"]
 
 
-def test_field_decorator_no_arguments():
+def test_field_decorator_no_arguments() -> None:
     class Page(ItemPage):
         @field()
         def name(self):
@@ -143,7 +144,7 @@ def to_item(self):
     assert page.to_item() == {"name": "Name"}
 
 
-def test_field_cache_sync():
+def test_field_cache_sync() -> None:
     class Page:
         _n_called_1 = 0
         _n_called_2 = 0
@@ -171,7 +172,7 @@ def n_called_2(self):
 
 
 @pytest.mark.asyncio
-async def test_field_cache_async():
+async def test_field_cache_async() -> None:
     class Page:
         _n_called_1 = 0
         _n_called_2 = 0
@@ -199,7 +200,7 @@ async def n_called_2(self):
 
 
 @pytest.mark.asyncio
-async def test_field_cache_async_locked():
+async def test_field_cache_async_locked() -> None:
     class Page:
         _n_called = 0
 
@@ -221,7 +222,7 @@ async def n_called(self):
 
 
 @pytest.mark.asyncio
-async def test_skip_nonitem_fields_async():
+async def test_skip_nonitem_fields_async() -> None:
     class ExtendedPage(Page):
         @field
         def new_attribute(self):
@@ -240,7 +241,7 @@ async def to_item(self) -> Item:
     assert item == Item(name="Hello!", price="$123")
 
 
-def test_skip_nonitem_fields():
+def test_skip_nonitem_fields() -> None:
     @attrs.define
     class SyncPage(Injectable):
         response: HttpResponse
@@ -274,7 +275,7 @@ def to_item(self) -> Item:
     assert item == Item(name="Hello!", price="$123")
 
 
-def test_field_meta():
+def test_field_meta() -> None:
     class MyPage(ItemPage):
         @field(meta={"good": True})
         def field1(self):
@@ -297,7 +298,7 @@ def to_item(self):
         assert fields["field2"].meta is None
 
 
-def test_field_subclassing():
+def test_field_subclassing() -> None:
     class Page(ItemPage):
         @field
         def field1(self):

tests/test_mixins.py

@@ -15,33 +15,33 @@ def my_page(book_list_html_response):
     return MyPage(book_list_html_response)
 
 
-def test_url(my_page):
+def test_url(my_page) -> None:
     assert my_page.url == "http://books.toscrape.com/index.html"
 
 
-def test_html(my_page, book_list_html):
+def test_html(my_page, book_list_html) -> None:
     assert my_page.html == book_list_html
 
 
-def test_xpath(my_page):
+def test_xpath(my_page) -> None:
     title = my_page.xpath(".//title/text()").get().strip()
     assert title == "All products | Books to Scrape - Sandbox"
 
 
-def test_css(my_page):
+def test_css(my_page) -> None:
     title = my_page.css("title::text").get().strip()
     assert title == "All products | Books to Scrape - Sandbox"
 
 
-def test_baseurl(my_page):
+def test_baseurl(my_page) -> None:
     assert my_page.base_url == "http://books.toscrape.com/index.html"
 
 
-def test_urljoin(my_page):
+def test_urljoin(my_page) -> None:
     assert my_page.urljoin("foo") == "http://books.toscrape.com/foo"
 
 
-def test_custom_baseurl():
+def test_custom_baseurl() -> None:
     body = b"""
     <html>
     <head>

tests/test_overrides.py

@@ -11,7 +11,7 @@
 POS = {POTopLevel1, POTopLevel2, POModule, PONestedPkg, PONestedModule}
 
 
-def test_override_rule_uniqueness():
+def test_override_rule_uniqueness() -> None:
     """The same instance of an OverrideRule with the same attribute values should
     have the same hash identity.
     """
@@ -34,7 +34,7 @@ def test_override_rule_uniqueness():
     assert hash(rule1) == hash(rule2)
 
 
-def test_list_page_objects_all():
+def test_list_page_objects_all() -> None:
     rules = default_registry.get_overrides()
     page_objects = {po.use for po in rules}
 
@@ -53,17 +53,19 @@ def test_list_page_objects_all():
     # registry's @handle_urls annotation was used.
     assert page_objects == POS.union({POLibSub})
     for rule in rules:
-        assert rule.instead_of == rule.use.expected_overrides, rule.use
-        assert rule.for_patterns == rule.use.expected_patterns, rule.use
-        assert rule.meta == rule.use.expected_meta, rule.use
+        # We're ignoring the types below since mypy expects ``Type[ItemPage]``
+        # which doesn't contain the ``expected_*`` fields in our tests.
+        assert rule.instead_of == rule.use.expected_overrides, rule.use  # type: ignore[attr-defined]
+        assert rule.for_patterns == rule.use.expected_patterns, rule.use  # type: ignore[attr-defined]
+        assert rule.meta == rule.use.expected_meta, rule.use  # type: ignore[attr-defined]
 
 
-def test_consume_module_not_existing():
+def test_consume_module_not_existing() -> None:
     with pytest.raises(ImportError):
         consume_modules("this_does_not_exist")
 
 
-def test_list_page_objects_all_consume():
+def test_list_page_objects_all_consume() -> None:
     """A test similar to the one above but calls ``consume_modules()`` to properly
     load the @handle_urls annotations from other modules/packages.
     """
@@ -73,7 +75,7 @@ def test_list_page_objects_all_consume():
     assert any(["po_lib_sub_not_imported" in po.__module__ for po in page_objects])
 
 
-def test_registry_search_overrides():
+def test_registry_search_overrides() -> None:
     rules = default_registry.search_overrides(use=POTopLevel2)
     assert len(rules) == 1
     assert rules[0].use == POTopLevel2
@@ -87,7 +89,7 @@ def test_registry_search_overrides():
     assert len(rules) == 0
 
 
-def test_from_override_rules():
+def test_from_override_rules() -> None:
     rules = [
         OverrideRule(
             for_patterns=Patterns(include=["sample.com"]),