1 files changed, 35 insertions, 0 deletions
diff --git a/tests/composite_pk/test_checks.py b/tests/composite_pk/test_checks.py
index c33f2ee2eb..21796aa871 100644
--- a/tests/composite_pk/test_checks.py
+++ b/tests/composite_pk/test_checks.py
@@ -268,3 +268,38 @@ class CompositePKChecksTests(TestCase):
                 ),
             ],
         )
+
+    def test_proxy_model_can_subclass_model_with_composite_pk(self):
+        class Foo(models.Model):
+            pk = models.CompositePrimaryKey("a", "b")
+            a = models.SmallIntegerField()
+            b = models.SmallIntegerField()
+
+        class Bar(Foo):
+            class Meta:
+                proxy = True
+
+        self.assertEqual(Foo.check(databases=self.databases), [])
+        self.assertEqual(Bar.check(databases=self.databases), [])
+
+    def test_proxy_model_does_not_check_superclass_composite_pk_errors(self):
+        class Foo(models.Model):
+            pk = models.CompositePrimaryKey("a", "b")
+            a = models.SmallIntegerField()
+
+        class Bar(Foo):
+            class Meta:
+                proxy = True
+
+        self.assertEqual(
+            Foo.check(databases=self.databases),
+            [
+                checks.Error(
+                    "'b' cannot be included in the composite primary key.",
+                    hint="'b' is not a valid field.",
+                    obj=Foo,
+                    id="models.E042",
+                ),
+            ],
+        )
+        self.assertEqual(Bar.check(databases=self.databases), [])