Commit 69a46c5c authored by Anssi Kääriäinen's avatar Anssi Kääriäinen
Browse files

Tests for various emptyqs tickets 

The tickets are either about different signature between qs.none() and
qs or problems with subclass types (either EmptyQS overrided the custom
qs class, or EmptyQS was overridden by another class - values() did
this).

Fixed #15959, fixed #17271, fixed #17712, fixed #19426
parent a2396a4c

tests/modeltests/basic/tests.py

+41 −1
Original line number Diff line number Diff line
@@ -4,7 +4,7 @@ from datetime import datetime 


from django.core.exceptions import ObjectDoesNotExist, MultipleObjectsReturned

from django.db.models.fields import Field, FieldDoesNotExist

from django.db.models.query import EmptyQuerySet

from django.db.models.query import QuerySet, EmptyQuerySet, ValuesListQuerySet

from django.test import TestCase, skipIfDBFeature, skipUnlessDBFeature

from django.utils import six

from django.utils.translation import ugettext_lazy
@@ -646,3 +646,43 @@ class ModelTest(TestCase): 
        with self.assertRaises(TypeError):

            EmptyQuerySet()

        self.assertTrue(isinstance(Article.objects.none(), EmptyQuerySet))



    def test_emptyqs_values(self):

        # test for #15959

        Article.objects.create(headline='foo', pub_date=datetime.now())

        with self.assertNumQueries(0):

            qs = Article.objects.none().values_list('pk')

            self.assertTrue(isinstance(qs, EmptyQuerySet))

            self.assertTrue(isinstance(qs, ValuesListQuerySet))

            self.assertEqual(len(qs), 0)



    def test_emptyqs_customqs(self):

        # A hacky test for custom QuerySet subclass - refs #17271

        Article.objects.create(headline='foo', pub_date=datetime.now())

        class CustomQuerySet(QuerySet):

            def do_something(self):

                return 'did something'



        qs = Article.objects.all()

        qs.__class__ = CustomQuerySet

        qs = qs.none()

        with self.assertNumQueries(0):

            self.assertEqual(len(qs), 0)

            self.assertTrue(isinstance(qs, EmptyQuerySet))

            self.assertEqual(qs.do_something(), 'did something')



    def test_emptyqs_values_order(self):

        # Tests for ticket #17712

        Article.objects.create(headline='foo', pub_date=datetime.now())

        with self.assertNumQueries(0):

            self.assertEqual(len(Article.objects.none().values_list('id').order_by('id')), 0)

        with self.assertNumQueries(0):

            self.assertEqual(len(Article.objects.none().filter(

                id__in=Article.objects.values_list('id', flat=True))), 0)



    @skipUnlessDBFeature('can_distinct_on_fields')

    def test_emptyqs_distinct(self):

        # Tests for #19426

        Article.objects.create(headline='foo', pub_date=datetime.now())

        with self.assertNumQueries(0):

            self.assertEqual(len(Article.objects.none().distinct('headline', 'pub_date')), 0)