from django.db import models

from django.test import SimpleTestCase

from .models import AutoModel, BigAutoModel, SmallAutoModel

from .test_integerfield import (

    BigIntegerFieldTests,

    IntegerFieldTests,

    SmallIntegerFieldTests,

)

class AutoFieldTests(IntegerFieldTests):

    model = AutoModel

    rel_db_type_class = models.IntegerField

class BigAutoFieldTests(BigIntegerFieldTests):

    model = BigAutoModel

    rel_db_type_class = models.BigIntegerField

class SmallAutoFieldTests(SmallIntegerFieldTests):

    model = SmallAutoModel

    rel_db_type_class = models.SmallIntegerField

class AutoFieldInheritanceTests(SimpleTestCase):

    def test_isinstance_of_autofield(self):

        for field in (models.BigAutoField, models.SmallAutoField):

            with self.subTest(field.__name__):

                self.assertIsInstance(field(), models.AutoField)

    def test_issubclass_of_autofield(self):

        class MyBigAutoField(models.BigAutoField):

            pass

        class MySmallAutoField(models.SmallAutoField):

            pass

        tests = [

            MyBigAutoField,

            MySmallAutoField,

            models.BigAutoField,

            models.SmallAutoField,

        ]

        for field in tests:

            with self.subTest(field.__name__):

                self.assertTrue(issubclass(field, models.AutoField))