Allows searching with SearchFilter in annotated fields

Fixes #6094

Author: andrzej3393

rest_framework/filters.py

@@ -79,6 +79,9 @@ def must_call_distinct(self, queryset, search_fields):
                 search_field = search_field[1:]
             parts = search_field.split(LOOKUP_SEP)
             for part in parts:
+                if isinstance(queryset, models.QuerySet) and part in queryset.query.annotations:
+                    # This field is annotated
+                    continue
                 field = opts.get_field(part)
                 if hasattr(field, 'get_path_info'):
                     # This field is a relation, update opts to follow the relation

tests/test_filters.py

@@ -304,6 +304,40 @@ class SearchListView(generics.ListAPIView):
         assert len(response.data) == 1
 
 
+class NumbersModel(models.Model):
+    a = models.IntegerField()
+    b = models.IntegerField()
+
+
+class NumbersSerializer(serializers.ModelSerializer):
+    a_plus_b = serializers.IntegerField()
+
+    class Meta:
+        model = NumbersModel
+        fields = ('a', 'b', 'a_plus_b')
+
+
+class SearchFilterAnnotatedFieldTests(TestCase):
+    @classmethod
+    def setUpTestData(cls):
+        NumbersModel.objects.create(a=1, b=2)
+        NumbersModel.objects.create(a=3, b=4)
+
+    def test_search_in_annotated_field(self):
+        class SearchListView(generics.ListAPIView):
+            queryset = NumbersModel.objects.annotate(
+                a_plus_b=models.F('a') + models.F('b')).all()
+            serializer_class = NumbersSerializer
+            filter_backends = (filters.SearchFilter,)
+            search_fields = ('a_plus_b',)
+
+        view = SearchListView.as_view()
+        request = factory.get('/', {'search': '3'})
+        response = view(request)
+        assert len(response.data) == 1
+        assert response.data[0]['a_plus_b'] == 3
+
+
 class OrderingFilterModel(models.Model):
     title = models.CharField(max_length=20, verbose_name='verbose title')
     text = models.CharField(max_length=100)