Fixed #34750 -- Fixed QuerySet.count() when grouping by unused multi-valued annotations.

Thanks Toan Vuong for the report.
Thanks Simon Charette for the review.

Regression in 59bea9efd2768102fc9d3aedda469502c218e9b7.

1 files changed, 41 insertions, 0 deletions

diff --git a/tests/aggregation/tests.py b/tests/aggregation/tests.py
index 9f2a7c8841..ad00afdcc1 100644
--- a/tests/aggregation/tests.py
+++ b/tests/aggregation/tests.py
@@ -2165,6 +2165,47 @@ class AggregateAnnotationPruningTests(TestCase):
         self.assertEqual(sql.count("select"), 2, "Subquery wrapping required")
         self.assertNotIn("authors_count", sql)
 
+    def test_unused_aliased_aggregate_and_annotation_reverse_fk(self):
+        Book.objects.create(
+            name="b3",
+            publisher=self.p2,
+            pages=1000,
+            rating=4.2,
+            price=50,
+            contact=self.a2,
+            pubdate=datetime.date.today(),
+        )
+        qs = Publisher.objects.annotate(
+            total_pages=Sum("book__pages"),
+            good_book=Case(
+                When(book__rating__gt=4.0, then=Value(True)),
+                default=Value(False),
+            ),
+        )
+        self.assertEqual(qs.count(), 3)
+
+    def test_unused_aliased_aggregate_and_annotation_reverse_fk_grouped(self):
+        Book.objects.create(
+            name="b3",
+            publisher=self.p2,
+            pages=1000,
+            rating=4.2,
+            price=50,
+            contact=self.a2,
+            pubdate=datetime.date.today(),
+        )
+        qs = (
+            Publisher.objects.values("id", "name")
+            .annotate(total_pages=Sum("book__pages"))
+            .annotate(
+                good_book=Case(
+                    When(book__rating__gt=4.0, then=Value(True)),
+                    default=Value(False),
+                )
+            )
+        )
+        self.assertEqual(qs.count(), 3)
+
     def test_non_aggregate_annotation_pruned(self):
         with CaptureQueriesContext(connection) as ctx:
             Book.objects.annotate(