Refs #21961 -- Added DatabaseFeatures.supports_on_delete_db_(cascade/null) feature flags.

Needed on MongoDB.

Co-Authored-By: Mariusz Felisiak <felisiak.mariusz@gmail.com>

2 files changed, 24 insertions, 20 deletions

diff --git a/tests/delete/models.py b/tests/delete/models.py
index bd9caf42a7..d8f81827be 100644
--- a/tests/delete/models.py
+++ b/tests/delete/models.py
@@ -49,17 +49,26 @@ class RelatedDbOptionParent(models.Model):
     p = models.ForeignKey(RelatedDbOptionGrandParent, models.DB_CASCADE, null=True)
 
 
-class RelatedDbOption(models.Model):
+class CascadeDbModel(models.Model):
     name = models.CharField(max_length=30)
+    db_cascade = models.ForeignKey(
+        RelatedDbOptionParent, models.DB_CASCADE, related_name="db_cascade_set"
+    )
+
+    class Meta:
+        required_db_features = {"supports_on_delete_db_cascade"}
+
+
+class SetNullDbModel(models.Model):
     db_setnull = models.ForeignKey(
         RelatedDbOptionParent,
         models.DB_SET_NULL,
         null=True,
         related_name="db_setnull_set",
     )
-    db_cascade = models.ForeignKey(
-        RelatedDbOptionParent, models.DB_CASCADE, related_name="db_cascade_set"
-    )
+
+    class Meta:
+        required_db_features = {"supports_on_delete_db_null"}
 
 
 class SetDefaultDbModel(models.Model):
@@ -159,15 +168,6 @@ def create_a(name):
     return a
 
 
-def create_related_db_option(name):
-    a = RelatedDbOption(name=name)
-    for name in ["db_setnull", "db_cascade"]:
-        r = RelatedDbOptionParent.objects.create()
-        setattr(a, name, r)
-    a.save()
-    return a
-
-
 class M(models.Model):
     m2m = models.ManyToManyField(R, related_name="m_set")
     m2m_through = models.ManyToManyField(R, through="MR", related_name="m_through_set")
diff --git a/tests/delete/tests.py b/tests/delete/tests.py
index 8d525d1e5f..664cdfb440 100644
--- a/tests/delete/tests.py
+++ b/tests/delete/tests.py
@@ -15,6 +15,7 @@ from .models import (
     Avatar,
     B,
     Base,
+    CascadeDbModel,
     Child,
     DeleteBottom,
     DeleteTop,
@@ -34,16 +35,15 @@ from .models import (
     RChild,
     RChildChild,
     Referrer,
-    RelatedDbOption,
     RelatedDbOptionGrandParent,
     RelatedDbOptionParent,
     RProxy,
     S,
     SetDefaultDbModel,
+    SetNullDbModel,
     T,
     User,
     create_a,
-    create_related_db_option,
     get_default_r,
 )
 
@@ -81,10 +81,13 @@ class OnDeleteTests(TestCase):
         a = A.objects.get(pk=a.pk)
         self.assertIsNone(a.setnull)
 
+    @skipUnlessDBFeature("supports_on_delete_db_null")
     def test_db_setnull(self):
-        a = create_related_db_option("db_setnull")
+        a = SetNullDbModel.objects.create(
+            db_setnull=RelatedDbOptionParent.objects.create()
+        )
         a.db_setnull.delete()
-        a = RelatedDbOption.objects.get(pk=a.pk)
+        a = SetNullDbModel.objects.get(pk=a.pk)
         self.assertIsNone(a.db_setnull)
 
     def test_setdefault(self):
@@ -394,20 +397,21 @@ class DeletionTests(TestCase):
         self.assertNumQueries(5, s.delete)
         self.assertFalse(S.objects.exists())
 
+    @skipUnlessDBFeature("supports_on_delete_db_cascade")
     def test_db_cascade(self):
         related_db_op = RelatedDbOptionParent.objects.create(
             p=RelatedDbOptionGrandParent.objects.create()
         )
-        RelatedDbOption.objects.bulk_create(
+        CascadeDbModel.objects.bulk_create(
             [
-                RelatedDbOption(db_cascade=related_db_op)
+                CascadeDbModel(db_cascade=related_db_op)
                 for _ in range(2 * GET_ITERATOR_CHUNK_SIZE)
             ]
         )
         with self.assertNumQueries(1):
             results = related_db_op.delete()
             self.assertEqual(results, (1, {"delete.RelatedDbOptionParent": 1}))
-        self.assertFalse(RelatedDbOption.objects.exists())
+        self.assertFalse(CascadeDbModel.objects.exists())
         self.assertFalse(RelatedDbOptionParent.objects.exists())
 
     def test_instance_update(self):