from django.test import TestCase

from models import Person, Book, Car, PersonManager, PublishedBookManager

class CustomManagerTests(TestCase):

    def test_manager(self):

        p1 = Person.objects.create(first_name="Bugs", last_name="Bunny", fun=True)

        p2 = Person.objects.create(first_name="Droopy", last_name="Dog", fun=False)

        self.assertQuerysetEqual(

            Person.objects.get_fun_people(), [

                "Bugs Bunny"

            ],

            unicode

        )

        # The RelatedManager used on the 'books' descriptor extends the default

        # manager

        self.assertTrue(isinstance(p2.books, PublishedBookManager))

        b1 = Book.published_objects.create(

            title="How to program", author="Rodney Dangerfield", is_published=True

        )

        b2 = Book.published_objects.create(

            title="How to be smart", author="Albert Einstein", is_published=False

        )

        # The default manager, "objects", doesn't exist, because a custom one

        # was provided.

        self.assertRaises(AttributeError, lambda: Book.objects)

        # The RelatedManager used on the 'authors' descriptor extends the

        # default manager

        self.assertTrue(isinstance(b2.authors, PersonManager))

        self.assertQuerysetEqual(

            Book.published_objects.all(), [

                "How to program",

            ],

            lambda b: b.title

        )

        c1 = Car.cars.create(name="Corvette", mileage=21, top_speed=180)

        c2 = Car.cars.create(name="Neon", mileage=31, top_speed=100)

        self.assertQuerysetEqual(

            Car.cars.order_by("name"), [

                "Corvette",

                "Neon",

            ],

            lambda c: c.name

        )

        self.assertQuerysetEqual(

            Car.fast_cars.all(), [

                "Corvette",

            ],

            lambda c: c.name

        )

        # Each model class gets a "_default_manager" attribute, which is a

        # reference to the first manager defined in the class. In this case,

        # it's "cars".

        self.assertQuerysetEqual(

            Car._default_manager.order_by("name"), [

                "Corvette",

                "Neon",

            ],

            lambda c: c.name

        )