| from operator import attrgetter |
| |
| from django.core.exceptions import FieldError |
| from django.test import TestCase |
| |
| from models import (Chef, CommonInfo, ItalianRestaurant, ParkingLot, Place, |
| Post, Restaurant, Student, StudentWorker, Supplier, Worker, MixinModel) |
| |
| |
| class ModelInheritanceTests(TestCase): |
| def test_abstract(self): |
| # The Student and Worker models both have 'name' and 'age' fields on |
| # them and inherit the __unicode__() method, just as with normal Python |
| # subclassing. This is useful if you want to factor out common |
| # information for programming purposes, but still completely |
| # independent separate models at the database level. |
| w1 = Worker.objects.create(name="Fred", age=35, job="Quarry worker") |
| w2 = Worker.objects.create(name="Barney", age=34, job="Quarry worker") |
| |
| s = Student.objects.create(name="Pebbles", age=5, school_class="1B") |
| |
| self.assertEqual(unicode(w1), "Worker Fred") |
| self.assertEqual(unicode(s), "Student Pebbles") |
| |
| # The children inherit the Meta class of their parents (if they don't |
| # specify their own). |
| self.assertQuerysetEqual( |
| Worker.objects.values("name"), [ |
| {"name": "Barney"}, |
| {"name": "Fred"}, |
| ], |
| lambda o: o |
| ) |
| |
| # Since Student does not subclass CommonInfo's Meta, it has the effect |
| # of completely overriding it. So ordering by name doesn't take place |
| # for Students. |
| self.assertEqual(Student._meta.ordering, []) |
| |
| # However, the CommonInfo class cannot be used as a normal model (it |
| # doesn't exist as a model). |
| self.assertRaises(AttributeError, lambda: CommonInfo.objects.all()) |
| |
| # A StudentWorker which does not exist is both a Student and Worker |
| # which does not exist. |
| self.assertRaises(Student.DoesNotExist, |
| StudentWorker.objects.get, pk=12321321 |
| ) |
| self.assertRaises(Worker.DoesNotExist, |
| StudentWorker.objects.get, pk=12321321 |
| ) |
| |
| # MultipleObjectsReturned is also inherited. |
| # This is written out "long form", rather than using __init__/create() |
| # because of a bug with diamond inheritance (#10808) |
| sw1 = StudentWorker() |
| sw1.name = "Wilma" |
| sw1.age = 35 |
| sw1.save() |
| sw2 = StudentWorker() |
| sw2.name = "Betty" |
| sw2.age = 24 |
| sw2.save() |
| |
| self.assertRaises(Student.MultipleObjectsReturned, |
| StudentWorker.objects.get, pk__lt=sw2.pk + 100 |
| ) |
| self.assertRaises(Worker.MultipleObjectsReturned, |
| StudentWorker.objects.get, pk__lt=sw2.pk + 100 |
| ) |
| |
| def test_multiple_table(self): |
| post = Post.objects.create(title="Lorem Ipsum") |
| # The Post model has distinct accessors for the Comment and Link models. |
| post.attached_comment_set.create(content="Save $ on V1agr@", is_spam=True) |
| post.attached_link_set.create( |
| content="The Web framework for perfections with deadlines.", |
| url="http://www.djangoproject.com/" |
| ) |
| |
| # The Post model doesn't have an attribute called |
| # 'attached_%(class)s_set'. |
| self.assertRaises(AttributeError, |
| getattr, post, "attached_%(class)s_set" |
| ) |
| |
| # The Place/Restaurant/ItalianRestaurant models all exist as |
| # independent models. However, the subclasses also have transparent |
| # access to the fields of their ancestors. |
| # Create a couple of Places. |
| p1 = Place.objects.create(name="Master Shakes", address="666 W. Jersey") |
| p2 = Place.objects.create(name="Ace Harware", address="1013 N. Ashland") |
| |
| # Test constructor for Restaurant. |
| r = Restaurant.objects.create( |
| name="Demon Dogs", |
| address="944 W. Fullerton", |
| serves_hot_dogs=True, |
| serves_pizza=False, |
| rating=2 |
| ) |
| # Test the constructor for ItalianRestaurant. |
| c = Chef.objects.create(name="Albert") |
| ir = ItalianRestaurant.objects.create( |
| name="Ristorante Miron", |
| address="1234 W. Ash", |
| serves_hot_dogs=False, |
| serves_pizza=False, |
| serves_gnocchi=True, |
| rating=4, |
| chef=c |
| ) |
| self.assertQuerysetEqual( |
| ItalianRestaurant.objects.filter(address="1234 W. Ash"), [ |
| "Ristorante Miron", |
| ], |
| attrgetter("name") |
| ) |
| ir.address = "1234 W. Elm" |
| ir.save() |
| self.assertQuerysetEqual( |
| ItalianRestaurant.objects.filter(address="1234 W. Elm"), [ |
| "Ristorante Miron", |
| ], |
| attrgetter("name") |
| ) |
| |
| # Make sure Restaurant and ItalianRestaurant have the right fields in |
| # the right order. |
| self.assertEqual( |
| [f.name for f in Restaurant._meta.fields], |
| ["id", "name", "address", "place_ptr", "rating", "serves_hot_dogs", "serves_pizza", "chef"] |
| ) |
| self.assertEqual( |
| [f.name for f in ItalianRestaurant._meta.fields], |
| ["id", "name", "address", "place_ptr", "rating", "serves_hot_dogs", "serves_pizza", "chef", "restaurant_ptr", "serves_gnocchi"], |
| ) |
| self.assertEqual(Restaurant._meta.ordering, ["-rating"]) |
| |
| # Even though p.supplier for a Place 'p' (a parent of a Supplier), a |
| # Restaurant object cannot access that reverse relation, since it's not |
| # part of the Place-Supplier Hierarchy. |
| self.assertQuerysetEqual(Place.objects.filter(supplier__name="foo"), []) |
| self.assertRaises(FieldError, |
| Restaurant.objects.filter, supplier__name="foo" |
| ) |
| |
| # Parent fields can be used directly in filters on the child model. |
| self.assertQuerysetEqual( |
| Restaurant.objects.filter(name="Demon Dogs"), [ |
| "Demon Dogs", |
| ], |
| attrgetter("name") |
| ) |
| self.assertQuerysetEqual( |
| ItalianRestaurant.objects.filter(address="1234 W. Elm"), [ |
| "Ristorante Miron", |
| ], |
| attrgetter("name") |
| ) |
| |
| # Filters against the parent model return objects of the parent's type. |
| p = Place.objects.get(name="Demon Dogs") |
| self.assertIs(type(p), Place) |
| |
| # Since the parent and child are linked by an automatically created |
| # OneToOneField, you can get from the parent to the child by using the |
| # child's name. |
| self.assertEqual( |
| p.restaurant, Restaurant.objects.get(name="Demon Dogs") |
| ) |
| self.assertEqual( |
| Place.objects.get(name="Ristorante Miron").restaurant.italianrestaurant, |
| ItalianRestaurant.objects.get(name="Ristorante Miron") |
| ) |
| self.assertEqual( |
| Restaurant.objects.get(name="Ristorante Miron").italianrestaurant, |
| ItalianRestaurant.objects.get(name="Ristorante Miron") |
| ) |
| |
| # This won't work because the Demon Dogs restaurant is not an Italian |
| # restaurant. |
| self.assertRaises(ItalianRestaurant.DoesNotExist, |
| lambda: p.restaurant.italianrestaurant |
| ) |
| # An ItalianRestaurant which does not exist is also a Place which does |
| # not exist. |
| self.assertRaises(Place.DoesNotExist, |
| ItalianRestaurant.objects.get, name="The Noodle Void" |
| ) |
| # MultipleObjectsReturned is also inherited. |
| self.assertRaises(Place.MultipleObjectsReturned, |
| Restaurant.objects.get, id__lt=12321 |
| ) |
| |
| # Related objects work just as they normally do. |
| s1 = Supplier.objects.create(name="Joe's Chickens", address="123 Sesame St") |
| s1.customers = [r, ir] |
| s2 = Supplier.objects.create(name="Luigi's Pasta", address="456 Sesame St") |
| s2.customers = [ir] |
| |
| # This won't work because the Place we select is not a Restaurant (it's |
| # a Supplier). |
| p = Place.objects.get(name="Joe's Chickens") |
| self.assertRaises(Restaurant.DoesNotExist, |
| lambda: p.restaurant |
| ) |
| |
| self.assertEqual(p.supplier, s1) |
| self.assertQuerysetEqual( |
| ir.provider.order_by("-name"), [ |
| "Luigi's Pasta", |
| "Joe's Chickens" |
| ], |
| attrgetter("name") |
| ) |
| self.assertQuerysetEqual( |
| Restaurant.objects.filter(provider__name__contains="Chickens"), [ |
| "Ristorante Miron", |
| "Demon Dogs", |
| ], |
| attrgetter("name") |
| ) |
| self.assertQuerysetEqual( |
| ItalianRestaurant.objects.filter(provider__name__contains="Chickens"), [ |
| "Ristorante Miron", |
| ], |
| attrgetter("name"), |
| ) |
| |
| park1 = ParkingLot.objects.create( |
| name="Main St", address="111 Main St", main_site=s1 |
| ) |
| park2 = ParkingLot.objects.create( |
| name="Well Lit", address="124 Sesame St", main_site=ir |
| ) |
| |
| self.assertEqual( |
| Restaurant.objects.get(lot__name="Well Lit").name, |
| "Ristorante Miron" |
| ) |
| |
| # The update() command can update fields in parent and child classes at |
| # once (although it executed multiple SQL queries to do so). |
| rows = Restaurant.objects.filter( |
| serves_hot_dogs=True, name__contains="D" |
| ).update( |
| name="Demon Puppies", serves_hot_dogs=False |
| ) |
| self.assertEqual(rows, 1) |
| |
| r1 = Restaurant.objects.get(pk=r.pk) |
| self.assertFalse(r1.serves_hot_dogs) |
| self.assertEqual(r1.name, "Demon Puppies") |
| |
| # The values() command also works on fields from parent models. |
| self.assertQuerysetEqual( |
| ItalianRestaurant.objects.values("name", "rating"), [ |
| {"rating": 4, "name": "Ristorante Miron"} |
| ], |
| lambda o: o |
| ) |
| |
| # select_related works with fields from the parent object as if they |
| # were a normal part of the model. |
| self.assertNumQueries(2, |
| lambda: ItalianRestaurant.objects.all()[0].chef |
| ) |
| self.assertNumQueries(1, |
| lambda: ItalianRestaurant.objects.select_related("chef")[0].chef |
| ) |
| |
| def test_mixin_init(self): |
| m = MixinModel() |
| self.assertEqual(m.other_attr, 1) |
