Fixed #17535 -- Optimized list generic views.

When allow_empty is False, prevented the view from loading
the entire queryset in memory when pagination is enabled.

1 files changed, 10 insertions, 0 deletions

diff --git a/tests/regressiontests/generic_views/list.py b/tests/regressiontests/generic_views/list.py
index 9ad00edc3b..b925758524 100644
--- a/tests/regressiontests/generic_views/list.py
+++ b/tests/regressiontests/generic_views/list.py
@@ -159,6 +159,16 @@ class ListViewTests(TestCase):
     def test_missing_items(self):
         self.assertRaises(ImproperlyConfigured, self.client.get, '/list/authors/invalid/')
 
+    def test_paginated_list_view_does_not_load_entire_table(self):
+        # Regression test for #17535
+        self._make_authors(3)
+        # 1 query for authors
+        with self.assertNumQueries(1):
+            self.client.get('/list/authors/notempty/')
+        # same as above + 1 query to test if authors exist + 1 query for pagination
+        with self.assertNumQueries(3):
+            self.client.get('/list/authors/notempty/paginated/')
+
     def _make_authors(self, n):
         Author.objects.all().delete()
         for i in range(n):