Refs #35224 -- Removed special-case GenericForeignKey system check.

django/contrib/contenttypes/apps.py

@@ -1,8 +1,5 @@
 from django.apps import AppConfig
-from django.contrib.contenttypes.checks import (
-    check_generic_foreign_keys,
-    check_model_name_lengths,
-)
+from django.contrib.contenttypes.checks import check_model_name_lengths
 from django.core import checks
 from django.db.models.signals import post_migrate, pre_migrate
 from django.utils.translation import gettext_lazy as _
@@ -18,5 +15,4 @@ class ContentTypesConfig(AppConfig):
     def ready(self):
         pre_migrate.connect(inject_rename_contenttypes_operations, sender=self)
         post_migrate.connect(create_contenttypes)
-        checks.register(check_generic_foreign_keys, checks.Tags.models)
         checks.register(check_model_name_lengths, checks.Tags.models)

django/contrib/contenttypes/checks.py

@@ -4,27 +4,6 @@ from django.apps import apps
 from django.core.checks import Error
 
 
-def check_generic_foreign_keys(app_configs=None, **kwargs):
-    from .fields import GenericForeignKey
-
-    if app_configs is None:
-        models = apps.get_models()
-    else:
-        models = chain.from_iterable(
-            app_config.get_models() for app_config in app_configs
-        )
-    errors = []
-    fields = (
-        obj
-        for model in models
-        for obj in vars(model).values()
-        if isinstance(obj, GenericForeignKey)
-    )
-    for field in fields:
-        errors.extend(field.check())
-    return errors
-
-
 def check_model_name_lengths(app_configs=None, **kwargs):
     if app_configs is None:
         models = apps.get_models()

django/contrib/contenttypes/fields.py

@@ -357,7 +357,10 @@ class GenericRelation(ForeignObject):
 
     def check(self, **kwargs):
         return [
-            *super().check(**kwargs),
+            *self._check_field_name(),
+            *self._check_related_query_name_is_valid(),
+            *self._check_relation_model_exists(),
+            *self._check_referencing_to_swapped_model(),
             *self._check_generic_foreign_key_existence(),
         ]
 

django/db/models/base.py

@@ -1789,6 +1789,8 @@ class Model(AltersData, metaclass=ModelBase):
         errors = []
         for field in cls._meta.local_fields:
             errors.extend(field.check(**kwargs))
+        for field in cls._meta.private_fields:
+            errors.extend(field.check(**kwargs))
         for field in cls._meta.local_many_to_many:
             errors.extend(field.check(from_model=cls, **kwargs))
         return errors

tests/contenttypes_tests/test_checks.py

@@ -122,10 +122,10 @@ class GenericForeignKeyTests(SimpleTestCase):
 
         with mock.patch.object(GenericForeignKey, "check") as check:
             checks.run_checks(app_configs=self.apps.get_app_configs())
-        check.assert_called_once_with()
+        check.assert_called_once_with(databases=None)
 
 
-@isolate_apps("contenttypes_tests")
+@isolate_apps("contenttypes_tests", attr_name="apps")
 class GenericRelationTests(SimpleTestCase):
     def test_valid_generic_relationship(self):
         class TaggedItem(models.Model):
@@ -253,6 +253,19 @@ class GenericRelationTests(SimpleTestCase):
             ],
         )
 
+    def test_generic_relation_checks_are_performed(self):
+        class TaggedItem(models.Model):
+            content_type = models.ForeignKey(ContentType, models.CASCADE)
+            object_id = models.PositiveIntegerField()
+            content_object = GenericForeignKey()
+
+        class InvalidBookmark(models.Model):
+            tags_ = GenericRelation("TaggedItem")
+
+        with mock.patch.object(GenericRelation, "check") as check:
+            checks.run_checks(app_configs=self.apps.get_app_configs())
+        check.assert_called_once_with(databases=None)
+
 
 @isolate_apps("contenttypes_tests", attr_name="apps")
 class ModelCheckTests(SimpleTestCase):

tests/model_fields/models.py

@@ -411,6 +411,12 @@ class RelatedJSONModel(models.Model):
         required_db_features = {"supports_json_field"}
 
 
+class GfkModel(models.Model):
+    object_id = models.PositiveIntegerField()
+    content_type = models.ForeignKey(ContentType, models.CASCADE)
+    gfk = GenericForeignKey()
+
+
 class AllFieldsModel(models.Model):
     big_integer = models.BigIntegerField()
     binary = models.BinaryField()
@@ -448,7 +454,7 @@ class AllFieldsModel(models.Model):
     object_id = models.PositiveIntegerField()
     content_type = models.ForeignKey(ContentType, models.CASCADE)
     gfk = GenericForeignKey()
-    gr = GenericRelation(DataModel)
+    gr = GenericRelation(GfkModel)
 
 
 class ManyToMany(models.Model):

tests/model_meta/models.py

@@ -5,7 +5,9 @@ from django.utils.translation import gettext_lazy as _
 
 
 class Relation(models.Model):
-    pass
+    content_type = models.ForeignKey(ContentType, models.CASCADE, related_name="+")
+    object_id = models.PositiveIntegerField()
+    content_object = GenericForeignKey()
 
 
 class InstanceOnlyDescriptor: