Fixed #18056 - Cleared aggregations on DateQuery.add_date_select

Cleared aggregations on add_date_select method so only distinct dates
are returned when dealing with a QuerySet that contained aggregations.
That would cause the query set to return repeated dates because it
would look for distinct (date kind, aggregation) pairs.

1 files changed, 20 insertions, 0 deletions

diff --git a/tests/modeltests/aggregation/tests.py b/tests/modeltests/aggregation/tests.py
index 433ea1641a..c23b32fc85 100644
--- a/tests/modeltests/aggregation/tests.py
+++ b/tests/modeltests/aggregation/tests.py
@@ -565,3 +565,23 @@ class BaseAggregateTestCase(TestCase):
                 (Decimal('82.8'), 1),
             ]
         )
+
+    def test_dates_with_aggregation(self):
+        """
+        Test that .dates() returns a distinct set of dates when applied to a
+        QuerySet with aggregation.
+
+        Refs #18056. Previously, .dates() would return distinct (date_kind,
+        aggregation) sets, in this case (year, num_authors), so 2008 would be
+        returned twice because there are books from 2008 with a different
+        number of authors.
+        """
+        dates = Book.objects.annotate(num_authors=Count("authors")).dates('pubdate', 'year')
+        self.assertQuerysetEqual(
+            dates, [
+                "datetime.datetime(1991, 1, 1, 0, 0)",
+                "datetime.datetime(1995, 1, 1, 0, 0)",
+                "datetime.datetime(2007, 1, 1, 0, 0)",
+                "datetime.datetime(2008, 1, 1, 0, 0)"
+            ]
+        )