Commit 2b76f19f authored by Marcin Biernat's avatar Marcin Biernat
Browse files

fixes #19263

parent 7ec2a21b

django/db/models/sql/where.py

+4 −0
Original line number Diff line number Diff line
@@ -204,6 +204,10 @@ class WhereNode(tree.Node): 
                raise EmptyResultSet

            if extra:

                return ('%s IN %s' % (field_sql, extra), params)

            if not params:

                # Empty params would generate invalid sql in subquery

                raise EmptyResultSet



            max_in_list_size = connection.ops.max_in_list_size()

            if max_in_list_size and len(params) > max_in_list_size:

                # Break up the params list into an OR of manageable chunks.

tests/regressiontests/queries/tests.py

+15 −0
Original line number Diff line number Diff line
@@ -2021,6 +2021,9 @@ class WeirdQuerysetSlicingTests(BaseQuerysetTest): 
        Article.objects.create(name='three', created=datetime.datetime.now())

        Article.objects.create(name='four', created=datetime.datetime.now())



        food = Food.objects.create(name='spam')

        Eaten.objects.create(meal='spam with eggs', food=food)



    def test_tickets_7698_10202(self):

        # People like to slice with '0' as the high-water mark.

        self.assertQuerysetEqual(Article.objects.all()[0:0], [])
@@ -2036,6 +2039,18 @@ class WeirdQuerysetSlicingTests(BaseQuerysetTest): 
        # ticket #12192

        self.assertNumQueries(0, lambda: list(Number.objects.all()[1:1]))



    def test_empty_sliced_subquery(self):

        # ticket #19263 - testing subqueries

        self.assertEqual(

            Eaten.objects.filter(food__in=Food.objects.all()[0:0]).count(),

            0)



    def test_empty_sliced_subquery_exclude(self):

        # ticket #19263 - testing subqueries

        self.assertEqual(

            Eaten.objects.exclude(food__in=Food.objects.all()[0:0]).count(),

            1)





class EscapingTests(TestCase):

    def test_ticket_7302(self):