add test for annotations

graphene_django/tests/test_query.py

@@ -1120,3 +1120,55 @@ def test_should_preserve_prefetch_related(django_assert_num_queries):
     with django_assert_num_queries(3) as captured:
         result = schema.execute(query)
     assert not result.errors
+
+
+def test_should_preserve_annotations():
+    class ReporterType(DjangoObjectType):
+        class Meta:
+            model = Reporter
+            interfaces = (graphene.relay.Node,)
+
+    class FilmType(DjangoObjectType):
+        reporters = DjangoConnectionField(ReporterType)
+        reporters_count = graphene.Int()
+
+        class Meta:
+            model = Film
+            interfaces = (graphene.relay.Node,)
+
+    class Query(graphene.ObjectType):
+        films = DjangoConnectionField(FilmType)
+
+        def resolve_films(root, info):
+            qs = Film.objects.prefetch_related("reporters")
+            return qs.annotate(reporters_count=models.Count("reporters"))
+
+    r1 = Reporter.objects.create(first_name="Dave", last_name="Smith")
+    r2 = Reporter.objects.create(first_name="Jane", last_name="Doe")
+
+    f1 = Film.objects.create()
+    f1.reporters.set([r1, r2])
+    f2 = Film.objects.create()
+    f2.reporters.set([r2])
+
+    query = """
+        query {
+            films {
+                edges {
+                    node {
+                        reportersCount
+                    }
+                }
+            }
+        }
+    """
+    schema = graphene.Schema(query=Query)
+    result = schema.execute(query)
+    assert not result.errors, str(result)
+
+    expected = {
+        "films": {
+            "edges": [{"node": {"reportersCount": 2}}, {"node": {"reportersCount": 1}}]
+        }
+    }
+    assert result.data == expected, str(result.data)