/tests/modeltests/custom_managers/tests.py

 1from django.test import TestCase
 2
 3from models import Person, Book, Car, PersonManager, PublishedBookManager
 4
 5
 6class CustomManagerTests(TestCase):
 7    def test_manager(self):
 8        p1 = Person.objects.create(first_name="Bugs", last_name="Bunny", fun=True)
 9        p2 = Person.objects.create(first_name="Droopy", last_name="Dog", fun=False)
10
11        self.assertQuerysetEqual(
12            Person.objects.get_fun_people(), [
13                "Bugs Bunny"
14            ],
15            unicode
16        )
17        # The RelatedManager used on the 'books' descriptor extends the default
18        # manager
19        self.assertTrue(isinstance(p2.books, PublishedBookManager))
20
21        b1 = Book.published_objects.create(
22            title="How to program", author="Rodney Dangerfield", is_published=True
23        )
24        b2 = Book.published_objects.create(
25            title="How to be smart", author="Albert Einstein", is_published=False
26        )
27
28        # The default manager, "objects", doesn't exist, because a custom one
29        # was provided.
30        self.assertRaises(AttributeError, lambda: Book.objects)
31
32        # The RelatedManager used on the 'authors' descriptor extends the
33        # default manager
34        self.assertTrue(isinstance(b2.authors, PersonManager))
35
36        self.assertQuerysetEqual(
37            Book.published_objects.all(), [
38                "How to program",
39            ],
40            lambda b: b.title
41        )
42
43        c1 = Car.cars.create(name="Corvette", mileage=21, top_speed=180)
44        c2 = Car.cars.create(name="Neon", mileage=31, top_speed=100)
45
46        self.assertQuerysetEqual(
47            Car.cars.order_by("name"), [
48                "Corvette",
49                "Neon",
50            ],
51            lambda c: c.name
52        )
53
54        self.assertQuerysetEqual(
55            Car.fast_cars.all(), [
56                "Corvette",
57            ],
58            lambda c: c.name
59        )
60
61        # Each model class gets a "_default_manager" attribute, which is a
62        # reference to the first manager defined in the class. In this case,
63        # it's "cars".
64
65        self.assertQuerysetEqual(
66            Car._default_manager.order_by("name"), [
67                "Corvette",
68                "Neon",
69            ],
70            lambda c: c.name
71        )