Commit 233b46f9 authored by Tim Graham's avatar Tim Graham
Browse files

Fixed #19263 -- Fixed crash when filtering using __in and an empty QuerySet. 

Thanks Marcin Biernat for the initial patch and tests.
parent 7c085002

django/db/models/sql/compiler.py

+4 −1
Original line number Diff line number Diff line
@@ -484,7 +484,10 @@ class SQLCompiler(object): 
        if obj.low_mark == 0 and obj.high_mark is None and not self.query.distinct_fields:

            # If there is no slicing in use, then we can safely drop all ordering

            obj.clear_ordering(True)

        return obj.get_compiler(connection=self.connection).as_sql(subquery=True)

        nested_sql = obj.get_compiler(connection=self.connection).as_sql(subquery=True)

        if nested_sql == ('', ()):

            raise EmptyResultSet

        return nested_sql



    def get_default_columns(self, start_alias=None, opts=None, from_parent=None):

        """

tests/queries/tests.py

+9 −0
Original line number Diff line number Diff line
@@ -2362,6 +2362,9 @@ 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], [])
@@ -2377,6 +2380,12 @@ class WeirdQuerysetSlicingTests(BaseQuerysetTest): 
        # ticket #12192

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



    def test_empty_sliced_subquery(self):

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



    def test_empty_sliced_subquery_exclude(self):

        self.assertEqual(Eaten.objects.exclude(food__in=Food.objects.all()[0:0]).count(), 1)





class EscapingTests(TestCase):

    def test_ticket_7302(self):