import os

from django.core.management import call_command

from django.test import TestCase, TransactionTestCase

from django.test.utils import extend_sys_path

from .models import (

    ConcreteModel,

    ConcreteModelSubclass,

    ConcreteModelSubclassProxy,

    ProxyModel,

)

class ProxyModelInheritanceTests(TransactionTestCase):

    """

    Proxy model inheritance across apps can result in migrate not creating the table

    for the proxied model (as described in #12286).  This test creates two dummy

    apps and calls migrate, then verifies that the table has been created.

    """

    available_apps = []

    def test_table_exists(self):

        with extend_sys_path(os.path.dirname(os.path.abspath(__file__))):

            with self.modify_settings(INSTALLED_APPS={"append": ["app1", "app2"]}):

                call_command("migrate", verbosity=0, run_syncdb=True)

                from app1.models import ProxyModel

                from app2.models import NiceModel

                self.assertEqual(NiceModel.objects.count(), 0)

                self.assertEqual(ProxyModel.objects.count(), 0)

class MultiTableInheritanceProxyTest(TestCase):

    def test_model_subclass_proxy(self):

        """

        Deleting an instance of a model proxying a multi-table inherited

        subclass should cascade delete down the whole inheritance chain (see

        #18083).

        """

        instance = ConcreteModelSubclassProxy.objects.create()

        instance.delete()

        self.assertEqual(0, ConcreteModelSubclassProxy.objects.count())

        self.assertEqual(0, ConcreteModelSubclass.objects.count())

        self.assertEqual(0, ConcreteModel.objects.count())

    def test_deletion_through_intermediate_proxy(self):

        child = ConcreteModelSubclass.objects.create()

        proxy = ProxyModel.objects.get(pk=child.pk)

        proxy.delete()

        self.assertFalse(ConcreteModel.objects.exists())

        self.assertFalse(ConcreteModelSubclass.objects.exists())