django/tests/regressiontests/model_inheritance_regress/tests.py

"""
Regression tests for Model inheritance behaviour.
"""

import datetime
from django.test import TestCase
from regressiontests.model_inheritance_regress.models import (
    Place, Restaurant, ItalianRestaurant, ParkingLot, ParkingLot2,
    ParkingLot3, Supplier, Wholesaler, Child, SelfRefChild, ArticleWithAuthor,
    M2MChild, QualityControl, DerivedM, Person, BirthdayParty, BachelorParty,
    MessyBachelorParty, InternalCertificationAudit)

class ModelInheritanceTest(TestCase):
    def test_model_inheritance(self):
        # Regression for #7350, #7202
        # Check that when you create a Parent object with a specific reference
        # to an existent child instance, saving the Parent doesn't duplicate
        # the child. This behaviour is only activated during a raw save - it
        # is mostly relevant to deserialization, but any sort of CORBA style
        # 'narrow()' API would require a similar approach.

        # Create a child-parent-grandparent chain
        place1 = Place(
            name="Guido's House of Pasta",
            address='944 W. Fullerton')
        place1.save_base(raw=True)
        restaurant = Restaurant(
            place_ptr=place1,
            serves_hot_dogs=True,
            serves_pizza=False)
        restaurant.save_base(raw=True)
        italian_restaurant = ItalianRestaurant(
            restaurant_ptr=restaurant,
            serves_gnocchi=True)
        italian_restaurant.save_base(raw=True)

        # Create a child-parent chain with an explicit parent link
        place2 = Place(name='Main St', address='111 Main St')
        place2.save_base(raw=True)
        park = ParkingLot(parent=place2, capacity=100)
        park.save_base(raw=True)

        # Check that no extra parent objects have been created.
        places = list(Place.objects.all())
        self.assertEqual(places, [place1, place2])

        dicts = list(Restaurant.objects.values('name','serves_hot_dogs'))
        self.assertEqual(dicts, [{
            'name': u"Guido's House of Pasta",
            'serves_hot_dogs': True
        }])

        dicts = list(ItalianRestaurant.objects.values(
            'name','serves_hot_dogs','serves_gnocchi'))
        self.assertEqual(dicts, [{
            'name': u"Guido's House of Pasta",
            'serves_gnocchi': True,
            'serves_hot_dogs': True,
        }])

        dicts = list(ParkingLot.objects.values('name','capacity'))
        self.assertEqual(dicts, [{
            'capacity': 100,
            'name': u'Main St',
        }])

        # You can also update objects when using a raw save.
        place1.name = "Guido's All New House of Pasta"
        place1.save_base(raw=True)

        restaurant.serves_hot_dogs = False
        restaurant.save_base(raw=True)

        italian_restaurant.serves_gnocchi = False
        italian_restaurant.save_base(raw=True)

        place2.name='Derelict lot'
        place2.save_base(raw=True)

        park.capacity = 50
        park.save_base(raw=True)

        # No extra parent objects after an update, either.
        places = list(Place.objects.all())
        self.assertEqual(places, [place2, place1])
        self.assertEqual(places[0].name, 'Derelict lot')
        self.assertEqual(places[1].name, "Guido's All New House of Pasta")

        dicts = list(Restaurant.objects.values('name','serves_hot_dogs'))
        self.assertEqual(dicts, [{
            'name': u"Guido's All New House of Pasta",
            'serves_hot_dogs': False,
        }])

        dicts = list(ItalianRestaurant.objects.values(
            'name', 'serves_hot_dogs', 'serves_gnocchi'))
        self.assertEqual(dicts, [{
            'name': u"Guido's All New House of Pasta",
            'serves_gnocchi': False,
            'serves_hot_dogs': False,
        }])

        dicts = list(ParkingLot.objects.values('name','capacity'))
        self.assertEqual(dicts, [{
            'capacity': 50,
            'name': u'Derelict lot',
        }])

        # If you try to raw_save a parent attribute onto a child object,
        # the attribute will be ignored.

        italian_restaurant.name = "Lorenzo's Pasta Hut"
        italian_restaurant.save_base(raw=True)

        # Note that the name has not changed
        # - name is an attribute of Place, not ItalianRestaurant
        dicts = list(ItalianRestaurant.objects.values(
            'name','serves_hot_dogs','serves_gnocchi'))
        self.assertEqual(dicts, [{
            'name': u"Guido's All New House of Pasta",
            'serves_gnocchi': False,
            'serves_hot_dogs': False,
        }])

    def test_issue_7105(self):
        # Regressions tests for #7105: dates() queries should be able to use
        # fields from the parent model as easily as the child.
        obj = Child.objects.create(
            name='child',
            created=datetime.datetime(2008, 6, 26, 17, 0, 0))
        dates = list(Child.objects.dates('created', 'month'))
        self.assertEqual(dates, [datetime.datetime(2008, 6, 1, 0, 0)])

    def test_issue_7276(self):
        # Regression test for #7276: calling delete() on a model with
        # multi-table inheritance should delete the associated rows from any
        # ancestor tables, as well as any descendent objects.
        place1 = Place(
            name="Guido's House of Pasta",
            address='944 W. Fullerton')
        place1.save_base(raw=True)
        restaurant = Restaurant(
            place_ptr=place1,
            serves_hot_dogs=True,
            serves_pizza=False)
        restaurant.save_base(raw=True)
        italian_restaurant = ItalianRestaurant(
            restaurant_ptr=restaurant,
            serves_gnocchi=True)
        italian_restaurant.save_base(raw=True)

        ident = ItalianRestaurant.objects.all()[0].id
        self.assertEqual(Place.objects.get(pk=ident), place1)
        xx = Restaurant.objects.create(
            name='a',
            address='xx',
            serves_hot_dogs=True,
            serves_pizza=False)

        # This should delete both Restuarants, plus the related places, plus
        # the ItalianRestaurant.
        Restaurant.objects.all().delete()

        self.assertRaises(
            Place.DoesNotExist,
            Place.objects.get,
            pk=ident)
        self.assertRaises(
            ItalianRestaurant.DoesNotExist,
            ItalianRestaurant.objects.get,
            pk=ident)

    def test_issue_6755(self):
        """
        Regression test for #6755
        """
        r = Restaurant(serves_pizza=False)
        r.save()
        self.assertEqual(r.id, r.place_ptr_id)
        orig_id = r.id
        r = Restaurant(place_ptr_id=orig_id, serves_pizza=True)
        r.save()
        self.assertEqual(r.id, orig_id)
        self.assertEqual(r.id, r.place_ptr_id)

    def test_issue_7488(self):
        # Regression test for #7488. This looks a little crazy, but it's the
        # equivalent of what the admin interface has to do for the edit-inline
        # case.
        suppliers = Supplier.objects.filter(
            restaurant=Restaurant(name='xx', address='yy'))
        suppliers = list(suppliers)
        self.assertEqual(suppliers, [])

    def test_issue_11764(self):
        """
        Regression test for #11764
        """
        wholesalers = list(Wholesaler.objects.all().select_related())
        self.assertEqual(wholesalers, [])

    def test_issue_7853(self):
        """
        Regression test for #7853
        If the parent class has a self-referential link, make sure that any
        updates to that link via the child update the right table.
        """
        obj = SelfRefChild.objects.create(child_data=37, parent_data=42)
        obj.delete()

    def test_get_next_previous_by_date(self):
        """
        Regression tests for #8076
        get_(next/previous)_by_date should work
        """
        c1 = ArticleWithAuthor(
            headline='ArticleWithAuthor 1',
            author="Person 1",
            pub_date=datetime.datetime(2005, 8, 1, 3, 0))
        c1.save()
        c2 = ArticleWithAuthor(
            headline='ArticleWithAuthor 2',
            author="Person 2",
            pub_date=datetime.datetime(2005, 8, 1, 10, 0))
        c2.save()
        c3 = ArticleWithAuthor(
            headline='ArticleWithAuthor 3',
            author="Person 3",
            pub_date=datetime.datetime(2005, 8, 2))
        c3.save()

        self.assertEqual(c1.get_next_by_pub_date(), c2)
        self.assertEqual(c2.get_next_by_pub_date(), c3)
        self.assertRaises(
            ArticleWithAuthor.DoesNotExist,
            c3.get_next_by_pub_date)
        self.assertEqual(c3.get_previous_by_pub_date(), c2)
        self.assertEqual(c2.get_previous_by_pub_date(), c1)
        self.assertRaises(
            ArticleWithAuthor.DoesNotExist,
            c1.get_previous_by_pub_date)

    def test_inherited_fields(self):
        """
        Regression test for #8825 and #9390
        Make sure all inherited fields (esp. m2m fields, in this case) appear
        on the child class.
        """
        m2mchildren = list(M2MChild.objects.filter(articles__isnull=False))
        self.assertEqual(m2mchildren, [])

        # Ordering should not include any database column more than once (this
        # is most likely to ocurr naturally with model inheritance, so we
        # check it here). Regression test for #9390. This necessarily pokes at
        # the SQL string for the query, since the duplicate problems are only
        # apparent at that late stage.
        qs = ArticleWithAuthor.objects.order_by('pub_date', 'pk')
        sql = qs.query.get_compiler(qs.db).as_sql()[0]
        fragment = sql[sql.find('ORDER BY'):]
        pos = fragment.find('pub_date')
        self.assertEqual(fragment.find('pub_date', pos + 1), -1)

    def test_queryset_update_on_parent_model(self):
        """
        Regression test for #10362
        It is possible to call update() and only change a field in
        an ancestor model.
        """
        article = ArticleWithAuthor.objects.create(
            author="fred",
            headline="Hey there!",
            pub_date=datetime.datetime(2009, 3, 1, 8, 0, 0))
        update = ArticleWithAuthor.objects.filter(
            author="fred").update(headline="Oh, no!")
        self.assertEqual(update, 1)
        update = ArticleWithAuthor.objects.filter(
            pk=article.pk).update(headline="Oh, no!")
        self.assertEqual(update, 1)

        derivedm1 = DerivedM.objects.create(
            customPK=44,
            base_name="b1",
            derived_name="d1")
        self.assertEqual(derivedm1.customPK, 44)
        self.assertEqual(derivedm1.base_name, 'b1')
        self.assertEqual(derivedm1.derived_name, 'd1')
        derivedms = list(DerivedM.objects.all())
        self.assertEqual(derivedms, [derivedm1])

    def test_use_explicit_o2o_to_parent_as_pk(self):
        """
        Regression tests for #10406
        If there's a one-to-one link between a child model and the parent and
        no explicit pk declared, we can use the one-to-one link as the pk on
        the child.
        """
        self.assertEqual(ParkingLot2._meta.pk.name, "parent")

        # However, the connector from child to parent need not be the pk on
        # the child at all.
        self.assertEqual(ParkingLot3._meta.pk.name, "primary_key")
        # the child->parent link
        self.assertEqual(
            ParkingLot3._meta.get_ancestor_link(Place).name,
            "parent")

    def test_all_fields_from_abstract_base_class(self):
        """
        Regression tests for #7588
        """
        # All fields from an ABC, including those inherited non-abstractly
        # should be available on child classes (#7588). Creating this instance
        # should work without error.
        QualityControl.objects.create(
            headline="Problems in Django",
            pub_date=datetime.datetime.now(),
            quality=10,
            assignee="adrian")

    def test_abstract_base_class_m2m_relation_inheritance(self):
        # Check that many-to-many relations defined on an abstract base class
        # are correctly inherited (and created) on the child class.
        p1 = Person.objects.create(name='Alice')
        p2 = Person.objects.create(name='Bob')
        p3 = Person.objects.create(name='Carol')
        p4 = Person.objects.create(name='Dave')

        birthday = BirthdayParty.objects.create(
            name='Birthday party for Alice')
        birthday.attendees = [p1, p3]

        bachelor = BachelorParty.objects.create(name='Bachelor party for Bob')
        bachelor.attendees = [p2, p4]

        parties = list(p1.birthdayparty_set.all())
        self.assertEqual(parties, [birthday])

        parties = list(p1.bachelorparty_set.all())
        self.assertEqual(parties, [])

        parties = list(p2.bachelorparty_set.all())
        self.assertEqual(parties, [bachelor])

        # Check that a subclass of a subclass of an abstract model doesn't get
        # it's own accessor.
        self.assertFalse(hasattr(p2, 'messybachelorparty_set'))

        # ... but it does inherit the m2m from it's parent
        messy = MessyBachelorParty.objects.create(
            name='Bachelor party for Dave')
        messy.attendees = [p4]
        messy_parent = messy.bachelorparty_ptr

        parties = list(p4.bachelorparty_set.all())
        self.assertEqual(parties, [bachelor, messy_parent])

    def test_11369(self):
        """verbose_name_plural correctly inherited from ABC if inheritance chain includes an abstract model."""
        # Regression test for #11369: verbose_name_plural should be inherited
        # from an ABC even when there are one or more intermediate
        # abstract models in the inheritance chain, for consistency with
        # verbose_name.
        self.assertEquals(
                InternalCertificationAudit._meta.verbose_name_plural,
                u'Audits'
        )