from django.test import TestCase

from .models import DumbCategory, NamedCategory, ProxyCategory

class ContainsTests(TestCase):

    @classmethod

    def setUpTestData(cls):

        cls.category = DumbCategory.objects.create()

        cls.proxy_category = ProxyCategory.objects.create()

    def test_unsaved_obj(self):

        msg = "QuerySet.contains() cannot be used on unsaved objects."

        with self.assertRaisesMessage(ValueError, msg):

            DumbCategory.objects.contains(DumbCategory())

    def test_obj_type(self):

        msg = "'obj' must be a model instance."

        with self.assertRaisesMessage(TypeError, msg):

            DumbCategory.objects.contains(object())

    def test_values(self):

        msg = "Cannot call QuerySet.contains() after .values() or .values_list()."

        with self.assertRaisesMessage(TypeError, msg):

            DumbCategory.objects.values_list("pk").contains(self.category)

        with self.assertRaisesMessage(TypeError, msg):

            DumbCategory.objects.values("pk").contains(self.category)

    def test_basic(self):

        with self.assertNumQueries(1):

            self.assertIs(DumbCategory.objects.contains(self.category), True)

        # QuerySet.contains() doesn't evaluate a queryset.

        with self.assertNumQueries(1):

            self.assertIs(DumbCategory.objects.contains(self.category), True)

    def test_evaluated_queryset(self):

        qs = DumbCategory.objects.all()

        proxy_qs = ProxyCategory.objects.all()

        # Evaluate querysets.

        list(qs)

        list(proxy_qs)

        with self.assertNumQueries(0):

            self.assertIs(qs.contains(self.category), True)

            self.assertIs(qs.contains(self.proxy_category), True)

            self.assertIs(proxy_qs.contains(self.category), True)

            self.assertIs(proxy_qs.contains(self.proxy_category), True)

    def test_proxy_model(self):

        with self.assertNumQueries(1):

            self.assertIs(DumbCategory.objects.contains(self.proxy_category), True)

        with self.assertNumQueries(1):

            self.assertIs(ProxyCategory.objects.contains(self.category), True)

    def test_wrong_model(self):

        qs = DumbCategory.objects.all()

        named_category = NamedCategory(name="category")

        with self.assertNumQueries(0):

            self.assertIs(qs.contains(named_category), False)

        # Evaluate the queryset.

        list(qs)

        with self.assertNumQueries(0):

            self.assertIs(qs.contains(named_category), False)