Fixed #27360 -- Added app or ModelAdmin details for AreadyRegistered exceptions.

1 files changed, 10 insertions, 1 deletions

diff --git a/tests/admin_registration/tests.py b/tests/admin_registration/tests.py
index 8601328647..93031bfbf3 100644
--- a/tests/admin_registration/tests.py
+++ b/tests/admin_registration/tests.py
@@ -30,10 +30,19 @@ class TestRegistration(SimpleTestCase):
 
     def test_prevent_double_registration(self):
         self.site.register(Person)
-        msg = 'The model Person is already registered'
+        msg = "The model Person is already registered in app 'admin_registration'."
         with self.assertRaisesMessage(admin.sites.AlreadyRegistered, msg):
             self.site.register(Person)
 
+    def test_prevent_double_registration_for_custom_admin(self):
+        class PersonAdmin(admin.ModelAdmin):
+            pass
+
+        self.site.register(Person, PersonAdmin)
+        msg = "The model Person is already registered with 'admin_registration.PersonAdmin'."
+        with self.assertRaisesMessage(admin.sites.AlreadyRegistered, msg):
+            self.site.register(Person, PersonAdmin)
+
     def test_registration_with_star_star_options(self):
         self.site.register(Person, search_fields=['name'])
         self.assertEqual(self.site._registry[Person].search_fields, ['name'])