Fixed #24266 -- Changed get_parent_list to return a list ordered by MRO.

Thanks to Aron Podrigal for the initial patch and Tim for the review.

2 files changed, 29 insertions, 1 deletions

diff --git a/tests/model_meta/models.py b/tests/model_meta/models.py
index ab9713dc38..b4ed9f89d2 100644
--- a/tests/model_meta/models.py
+++ b/tests/model_meta/models.py
@@ -118,3 +118,20 @@ class Relating(models.Model):
     # ManyToManyField to Person
     people = models.ManyToManyField(Person, related_name='relating_people')
     people_hidden = models.ManyToManyField(Person, related_name='+')
+
+
+# ParentListTests models
+class CommonAncestor(models.Model):
+    pass
+
+
+class FirstParent(CommonAncestor):
+    first_ancestor = models.OneToOneField(CommonAncestor, primary_key=True, parent_link=True)
+
+
+class SecondParent(CommonAncestor):
+    second_ancestor = models.OneToOneField(CommonAncestor, primary_key=True, parent_link=True)
+
+
+class Child(FirstParent, SecondParent):
+    pass
diff --git a/tests/model_meta/tests.py b/tests/model_meta/tests.py
index 1a0c2de9f3..36b65f5ab8 100644
--- a/tests/model_meta/tests.py
+++ b/tests/model_meta/tests.py
@@ -5,7 +5,10 @@ from django.db.models.fields import related, CharField, Field
 from django.db.models.options import IMMUTABLE_WARNING, EMPTY_RELATION_TREE
 from django.test import TestCase
 
-from .models import Relation, AbstractPerson, BasePerson, Person, ProxyPerson, Relating
+from .models import (
+    Relation, AbstractPerson, BasePerson, Person, ProxyPerson, Relating,
+    CommonAncestor, FirstParent, SecondParent, Child
+)
 from .results import TEST_RESULTS
 
 
@@ -245,3 +248,11 @@ class RelationTreeTests(TestCase):
             ])
         )
         self.assertEqual([field.related_query_name() for field in AbstractPerson._meta._relation_tree], [])
+
+
+class ParentListTests(TestCase):
+    def test_get_parent_list(self):
+        self.assertEqual(CommonAncestor._meta.get_parent_list(), [])
+        self.assertEqual(FirstParent._meta.get_parent_list(), [CommonAncestor])
+        self.assertEqual(SecondParent._meta.get_parent_list(), [CommonAncestor])
+        self.assertEqual(Child._meta.get_parent_list(), [FirstParent, SecondParent, CommonAncestor])