Ticket #31506: test_31506.diff

tests/expressions/tests.py

@@ -900 +900 @@
         queryset = Result.objects.filter(result_time__range=within_experiment_time)
         self.assertQuerysetEqual(queryset, ["<Result: Result at 2016-02-04 15:00:00>"])
 
+    def test_31506(self):
+        start = datetime.datetime(2016, 2, 3, 15, 0, 0)
+        end = datetime.datetime(2016, 2, 5, 15, 0, 0)
+        experiment_1 = Experiment.objects.create(
+            name='Integrity testing',
+            assigned=start.date(),
+            start=start,
+            end=end,
+            completed=end.date(),
+            estimated_time=end - start,
+        )
+        qs = Experiment.objects.annotate(
+            wrapped_date=ExpressionWrapper(
+                F('assigned') - datetime.timedelta(days=1),
+                output_field=DateField(),
+            ),
+        )
+        self.assertEqual(qs.first().wrapped_date, datetime.date(2016, 2, 2))
+
 
 class FTests(SimpleTestCase):