Tested Model.get_next/prev_by_FIELD() on unsaved models.

1 files changed, 7 insertions, 0 deletions

diff --git a/tests/model_regress/tests.py b/tests/model_regress/tests.py
index 6c4cecf43b..23390c0d81 100644
--- a/tests/model_regress/tests.py
+++ b/tests/model_regress/tests.py
@@ -178,6 +178,13 @@ class ModelTests(TestCase):
             e.get_previous_by_when().when, datetime.datetime(2000, 1, 1, 6, 1, 1)
         )
 
+    def test_get_next_prev_by_field_unsaved(self):
+        msg = 'get_next/get_previous cannot be used on unsaved objects.'
+        with self.assertRaisesMessage(ValueError, msg):
+            Event().get_next_by_when()
+        with self.assertRaisesMessage(ValueError, msg):
+            Event().get_previous_by_when()
+
     def test_primary_key_foreign_key_types(self):
         # Check Department and Worker (non-default PK type)
         d = Department.objects.create(id=10, name="IT")