Fixed #36973 -- Made fields.E348 check detect further clashes between managers and related_names.

Clashes were only detected for self-referential relationships, i.e. ForeignKey("self").

Refs #22977. Bug in 6888375c53476011754f778deabc6cdbfa327011.

Thanks JaeHyuckSa for the thorough review!

1 files changed, 29 insertions, 3 deletions

diff --git a/tests/invalid_models_tests/test_relative_fields.py b/tests/invalid_models_tests/test_relative_fields.py
index 51b1de1494..a6edcc4e04 100644
--- a/tests/invalid_models_tests/test_relative_fields.py
+++ b/tests/invalid_models_tests/test_relative_fields.py
@@ -1579,11 +1579,12 @@ class RelatedQueryNameClashWithManagerTests(SimpleTestCase):
             Author.check(),
             [
                 Error(
-                    "Related name 'authors' for 'Author.mentor' clashes with the name "
-                    "of a model manager.",
+                    "Related name 'authors' for 'invalid_models_tests.Author.mentor' "
+                    "clashes with the name of a model manager.",
                     hint=(
                         "Rename the model manager or change the related_name argument "
-                        "in the definition for field 'Author.mentor'."
+                        "in the definition for field "
+                        "'invalid_models_tests.Author.mentor'."
                     ),
                     obj=Author._meta.get_field("mentor"),
                     id="fields.E348",
@@ -1591,6 +1592,31 @@ class RelatedQueryNameClashWithManagerTests(SimpleTestCase):
             ],
         )
 
+    def test_clash_between_rel_name_and_manager_non_self_referential(self):
+        class Thing(models.Model):
+            items = models.Manager()
+
+        class Item(models.Model):
+            thing = models.ForeignKey(Thing, models.CASCADE, related_name="items")
+            something = models.ForeignKey(Thing, models.CASCADE, related_name="+")
+
+        self.assertEqual(
+            Item.check(),
+            [
+                Error(
+                    "Related name 'items' for 'invalid_models_tests.Item.thing' "
+                    "clashes with the name of a model manager.",
+                    hint=(
+                        "Rename the model manager or change the related_name argument "
+                        "in the definition for field 'invalid_models_tests.Item.thing'."
+                    ),
+                    obj=Item._meta.get_field("thing"),
+                    id="fields.E348",
+                )
+            ],
+        )
+        self.assertEqual(Thing.check(), [])
+
 
 @isolate_apps("invalid_models_tests")
 class SelfReferentialM2MClashTests(SimpleTestCase):