[2.0.x] Fixed #27846 -- Made Model.refresh_from_db() clear cached relations.

Backport of a7b5ad8b19a08d7d57302ece74f6e26d2887fd9f from master

2 files changed, 16 insertions, 1 deletions

diff --git a/tests/basic/models.py b/tests/basic/models.py
index c08b147ac4..40de6ae7de 100644
--- a/tests/basic/models.py
+++ b/tests/basic/models.py
@@ -17,6 +17,10 @@ class Article(models.Model):
         return self.headline
 
 
+class FeaturedArticle(models.Model):
+    article = models.OneToOneField(Article, models.CASCADE, related_name='featured')
+
+
 class ArticleSelectOnSave(Article):
     class Meta:
         proxy = True
diff --git a/tests/basic/tests.py b/tests/basic/tests.py
index c44e17dd24..5f608dab6f 100644
--- a/tests/basic/tests.py
+++ b/tests/basic/tests.py
@@ -11,7 +11,7 @@ from django.test import (
 )
 from django.utils.translation import gettext_lazy
 
-from .models import Article, ArticleSelectOnSave, SelfRef
+from .models import Article, ArticleSelectOnSave, FeaturedArticle, SelfRef
 
 
 class ModelInstanceCreationTests(TestCase):
@@ -745,3 +745,14 @@ class ModelRefreshTests(TestCase):
         a = Article.objects.create(pub_date=self._truncate_ms(datetime.now()))
         with self.assertNumQueries(0):
             a.refresh_from_db(fields=[])
+
+    def test_refresh_clears_reverse_related(self):
+        """refresh_from_db() clear cached reverse relations."""
+        article = Article.objects.create(
+            headline='Parrot programs in Python',
+            pub_date=datetime(2005, 7, 28),
+        )
+        self.assertFalse(hasattr(article, 'featured'))
+        FeaturedArticle.objects.create(article_id=article.pk)
+        article.refresh_from_db()
+        self.assertTrue(hasattr(article, 'featured'))