import unittest
import uuid

from django.core.checks import Error
from django.core.checks import Warning as DjangoWarning
from django.db import connection, models
from django.test import SimpleTestCase, TestCase, skipIfDBFeature, skipUnlessDBFeature
from django.test.utils import isolate_apps, override_settings
from django.utils.functional import lazy
from django.utils.timezone import now
from django.utils.translation import gettext_lazy as _
from django.utils.version import get_docs_version


@isolate_apps("invalid_models_tests")
class AutoFieldTests(SimpleTestCase):
    def test_valid_case(self):
        class Model(models.Model):
            id = models.AutoField(primary_key=True)

        field = Model._meta.get_field("id")
        self.assertEqual(field.check(), [])

    def test_primary_key(self):
        # primary_key must be True. Refs #12467.
        class Model(models.Model):
            field = models.AutoField(primary_key=False)

            # Prevent Django from autocreating `id` AutoField, which would
            # result in an error, because a model must have exactly one
            # AutoField.
            another = models.IntegerField(primary_key=True)

        field = Model._meta.get_field("field")
        self.assertEqual(
            field.check(),
            [
                Error(
                    "AutoFields must set primary_key=True.",
                    obj=field,
                    id="fields.E100",
                ),
            ],
        )

    def test_max_length_warning(self):
        class Model(models.Model):
            auto = models.AutoField(primary_key=True, max_length=2)

        field = Model._meta.get_field("auto")
        self.assertEqual(
            field.check(),
            [
                DjangoWarning(
                    "'max_length' is ignored when used with %s."
                    % field.__class__.__name__,
                    hint="Remove 'max_length' from field",
                    obj=field,
                    id="fields.W122",
                ),
            ],
        )


@isolate_apps("invalid_models_tests")
class BinaryFieldTests(SimpleTestCase):
    def test_valid_default_value(self):
        class Model(models.Model):
            field1 = models.BinaryField(default=b"test")
            field2 = models.BinaryField(default=None)

        for field_name in ("field1", "field2"):
            field = Model._meta.get_field(field_name)
            self.assertEqual(field.check(), [])

    def test_str_default_value(self):
        class Model(models.Model):
            field = models.BinaryField(default="test")

        field = Model._meta.get_field("field")
        self.assertEqual(
            field.check(),
            [
                Error(
                    "BinaryField's default cannot be a string. Use bytes content "
                    "instead.",
                    obj=field,
                    id="fields.E170",
                ),
            ],
        )


@isolate_apps("invalid_models_tests")
class CharFieldTests(TestCase):
    def test_valid_field(self):
        class Model(models.Model):
            field = models.CharField(
                max_length=255,
                choices=[
                    ("1", "item1"),
                    ("2", "item2"),
                ],
                db_index=True,
            )

        field = Model._meta.get_field("field")
        self.assertEqual(field.check(), [])

    def test_missing_max_length(self):
        class Model(models.Model):
            field = models.CharField()

        field = Model._meta.get_field("field")
        expected = (
            []
            if connection.features.supports_unlimited_charfield
            else [
                Error(
                    "CharFields must define a 'max_length' attribute.",
                    obj=field,
                    id="fields.E120",
                ),
            ]
        )
        self.assertEqual(field.check(), expected)

    def test_negative_max_length(self):
        class Model(models.Model):
            field = models.CharField(max_length=-1)

        field = Model._meta.get_field("field")
        self.assertEqual(
            field.check(),
            [
                Error(
                    "'max_length' must be a positive integer.",
                    obj=field,
                    id="fields.E121",
                ),
            ],
        )

    def test_bad_max_length_value(self):
        class Model(models.Model):
            field = models.CharField(max_length="bad")

        field = Model._meta.get_field("field")
        self.assertEqual(
            field.check(),
            [
                Error(
                    "'max_length' must be a positive integer.",
                    obj=field,
                    id="fields.E121",
                ),
            ],
        )

    def test_str_max_length_value(self):
        class Model(models.Model):
            field = models.CharField(max_length="20")

        field = Model._meta.get_field("field")
        self.assertEqual(
            field.check(),
            [
                Error(
                    "'max_length' must be a positive integer.",
                    obj=field,
                    id="fields.E121",
                ),
            ],
        )

    def test_str_max_length_type(self):
        class Model(models.Model):
            field = models.CharField(max_length=True)

        field = Model._meta.get_field("field")
        self.assertEqual(
            field.check(),
            [
                Error(
                    "'max_length' must be a positive integer.",
                    obj=field,
                    id="fields.E121",
                ),
            ],
        )

    def test_non_iterable_choices(self):
        class Model(models.Model):
            field = models.CharField(max_length=10, choices="bad")

        field = Model._meta.get_field("field")
        self.assertEqual(
            field.check(),
            [
                Error(
                    "'choices' must be an iterable (e.g., a list or tuple).",
                    obj=field,
                    id="fields.E004",
                ),
            ],
        )

    def test_non_iterable_choices_two_letters(self):
        """Two letters isn't a valid choice pair."""

        class Model(models.Model):
            field = models.CharField(max_length=10, choices=["ab"])

        field = Model._meta.get_field("field")
        self.assertEqual(
            field.check(),
            [
                Error(
                    "'choices' must be an iterable containing (actual value, "
                    "human readable name) tuples.",
                    obj=field,
                    id="fields.E005",
                ),
            ],
        )

    def test_iterable_of_iterable_choices(self):
        class ThingItem:
            def __init__(self, value, display):
                self.value = value
                self.display = display

            def __iter__(self):
                return iter((self.value, self.display))

            def __len__(self):
                return 2

        class Things:
            def __iter__(self):
                return iter((ThingItem(1, 2), ThingItem(3, 4)))

        class ThingWithIterableChoices(models.Model):
            thing = models.CharField(max_length=100, blank=True, choices=Things())

        self.assertEqual(ThingWithIterableChoices._meta.get_field("thing").check(), [])

    def test_choices_containing_non_pairs(self):
        class Model(models.Model):
            field = models.CharField(max_length=10, choices=[(1, 2, 3), (1, 2, 3)])

        class Model2(models.Model):
            field = models.IntegerField(choices=[0])

        for model in (Model, Model2):
            with self.subTest(model.__name__):
                field = model._meta.get_field("field")
                self.assertEqual(
                    field.check(),
                    [
                        Error(
                            "'choices' must be an iterable containing (actual "
                            "value, human readable name) tuples.",
                            obj=field,
                            id="fields.E005",
                        ),
                    ],
                )

    def test_choices_containing_lazy(self):
        class Model(models.Model):
            field = models.CharField(
                max_length=10, choices=[["1", _("1")], ["2", _("2")]]
            )

        self.assertEqual(Model._meta.get_field("field").check(), [])

    def test_lazy_choices(self):
        class Model(models.Model):
            field = models.CharField(
                max_length=10, choices=lazy(lambda: [[1, "1"], [2, "2"]], tuple)()
            )

        self.assertEqual(Model._meta.get_field("field").check(), [])

    def test_choices_named_group(self):
        class Model(models.Model):
            field = models.CharField(
                max_length=10,
                choices=[
                    ["knights", [["L", "Lancelot"], ["G", "Galahad"]]],
                    ["wizards", [["T", "Tim the Enchanter"]]],
                    ["R", "Random character"],
                ],
            )

        self.assertEqual(Model._meta.get_field("field").check(), [])

    def test_choices_named_group_non_pairs(self):
        class Model(models.Model):
            field = models.CharField(
                max_length=10,
                choices=[["knights", [["L", "Lancelot", "Du Lac"]]]],
            )

        field = Model._meta.get_field("field")
        self.assertEqual(
            field.check(),
            [
                Error(
                    "'choices' must be an iterable containing (actual value, "
                    "human readable name) tuples.",
                    obj=field,
                    id="fields.E005",
                ),
            ],
        )

    def test_choices_named_group_bad_structure(self):
        class Model(models.Model):
            field = models.CharField(
                max_length=10,
                choices=[
                    [
                        "knights",
                        [
                            ["Noble", [["G", "Galahad"]]],
                            ["Combative", [["L", "Lancelot"]]],
                        ],
                    ],
                ],
            )

        field = Model._meta.get_field("field")
        self.assertEqual(
            field.check(),
            [
                Error(
                    "'choices' must be an iterable containing (actual value, "
                    "human readable name) tuples.",
                    obj=field,
                    id="fields.E005",
                ),
            ],
        )

    def test_choices_named_group_lazy(self):
        class Model(models.Model):
            field = models.CharField(
                max_length=10,
                choices=[
                    [_("knights"), [["L", _("Lancelot")], ["G", _("Galahad")]]],
                    ["R", _("Random character")],
                ],
            )

        self.assertEqual(Model._meta.get_field("field").check(), [])

    def test_choices_in_max_length(self):
        class Model(models.Model):
            field = models.CharField(
                max_length=2,
                choices=[("ABC", "Value Too Long!"), ("OK", "Good")],
            )
            group = models.CharField(
                max_length=2,
                choices=[
                    ("Nested", [("OK", "Good"), ("Longer", "Longer")]),
                    ("Grouped", [("Bad", "Bad")]),
                ],
            )

        for name, choice_max_length in (("field", 3), ("group", 6)):
            with self.subTest(name):
                field = Model._meta.get_field(name)
                self.assertEqual(
                    field.check(),
                    [
                        Error(
                            "'max_length' is too small to fit the longest value "
                            "in 'choices' (%d characters)." % choice_max_length,
                            obj=field,
                            id="fields.E009",
                        ),
                    ],
                )

    def test_bad_db_index_value(self):
        class Model(models.Model):
            field = models.CharField(max_length=10, db_index="bad")

        field = Model._meta.get_field("field")
        self.assertEqual(
            field.check(),
            [
                Error(
                    "'db_index' must be None, True or False.",
                    obj=field,
                    id="fields.E006",
                ),
            ],
        )

    def test_bad_validators(self):
        class Model(models.Model):
            field = models.CharField(max_length=10, validators=[True])

        field = Model._meta.get_field("field")
        self.assertEqual(
            field.check(),
            [
                Error(
                    "All 'validators' must be callable.",
                    hint=(
                        "validators[0] (True) isn't a function or instance of a "
                        "validator class."
                    ),
                    obj=field,
                    id="fields.E008",
                ),
            ],
        )

    @unittest.skipUnless(connection.vendor == "mysql", "Test valid only for MySQL")
    def test_too_long_char_field_under_mysql(self):
        from django.db.backends.mysql.validation import DatabaseValidation

        class Model(models.Model):
            field = models.CharField(unique=True, max_length=256)

        field = Model._meta.get_field("field")
        validator = DatabaseValidation(connection=connection)
        self.assertEqual(
            validator.check_field(field),
            [
                DjangoWarning(
                    "%s may not allow unique CharFields to have a max_length > "
                    "255." % connection.display_name,
                    hint=(
                        "See: https://docs.djangoproject.com/en/%s/ref/databases/"
                        "#mysql-character-fields" % get_docs_version()
                    ),
                    obj=field,
                    id="mysql.W003",
                )
            ],
        )

    def test_db_collation(self):
        class Model(models.Model):
            field = models.CharField(max_length=100, db_collation="anything")

        field = Model._meta.get_field("field")
        error = Error(
            "%s does not support a database collation on CharFields."
            % connection.display_name,
            id="fields.E190",
            obj=field,
        )
        expected = (
            [] if connection.features.supports_collation_on_charfield else [error]
        )
        self.assertEqual(field.check(databases=self.databases), expected)

    def test_db_collation_required_db_features(self):
        class Model(models.Model):
            field = models.CharField(max_length=100, db_collation="anything")

            class Meta:
                required_db_features = {"supports_collation_on_charfield"}

        field = Model._meta.get_field("field")
        self.assertEqual(field.check(databases=self.databases), [])


@isolate_apps("invalid_models_tests")
class DateFieldTests(SimpleTestCase):
    maxDiff = None

    def test_auto_now_and_auto_now_add_raise_error(self):
        class Model(models.Model):
            field0 = models.DateTimeField(auto_now=True, auto_now_add=True, default=now)
            field1 = models.DateTimeField(
                auto_now=True, auto_now_add=False, default=now
            )
            field2 = models.DateTimeField(
                auto_now=False, auto_now_add=True, default=now
            )
            field3 = models.DateTimeField(
                auto_now=True, auto_now_add=True, default=None
            )

        expected = []
        checks = []
        for i in range(4):
            field = Model._meta.get_field("field%d" % i)
            expected.append(
                Error(
                    "The options auto_now, auto_now_add, and default "
                    "are mutually exclusive. Only one of these options "
                    "may be present.",
                    obj=field,
                    id="fields.E160",
                )
            )
            checks.extend(field.check())
            self.assertEqual(checks, expected)

    def test_fix_default_value(self):
        class Model(models.Model):
            field_dt = models.DateField(default=now())
            field_d = models.DateField(default=now().date())
            field_now = models.DateField(default=now)

        field_dt = Model._meta.get_field("field_dt")
        field_d = Model._meta.get_field("field_d")
        field_now = Model._meta.get_field("field_now")
        errors = field_dt.check()
        errors.extend(field_d.check())
        errors.extend(field_now.check())  # doesn't raise a warning
        self.assertEqual(
            errors,
            [
                DjangoWarning(
                    "Fixed default value provided.",
                    hint="It seems you set a fixed date / time / datetime "
                    "value as default for this field. This may not be "
                    "what you want. If you want to have the current date "
                    "as default, use `django.utils.timezone.now`",
                    obj=field_dt,
                    id="fields.W161",
                ),
                DjangoWarning(
                    "Fixed default value provided.",
                    hint="It seems you set a fixed date / time / datetime "
                    "value as default for this field. This may not be "
                    "what you want. If you want to have the current date "
                    "as default, use `django.utils.timezone.now`",
                    obj=field_d,
                    id="fields.W161",
                ),
            ],
        )

    @override_settings(USE_TZ=True)
    def test_fix_default_value_tz(self):
        self.test_fix_default_value()


@isolate_apps("invalid_models_tests")
class DateTimeFieldTests(SimpleTestCase):
    maxDiff = None

    def test_fix_default_value(self):
        class Model(models.Model):
            field_dt = models.DateTimeField(default=now())
            field_d = models.DateTimeField(default=now().date())
            field_now = models.DateTimeField(default=now)

        field_dt = Model._meta.get_field("field_dt")
        field_d = Model._meta.get_field("field_d")
        field_now = Model._meta.get_field("field_now")
        errors = field_dt.check()
        errors.extend(field_d.check())
        errors.extend(field_now.check())  # doesn't raise a warning
        self.assertEqual(
            errors,
            [
                DjangoWarning(
                    "Fixed default value provided.",
                    hint="It seems you set a fixed date / time / datetime "
                    "value as default for this field. This may not be "
                    "what you want. If you want to have the current date "
                    "as default, use `django.utils.timezone.now`",
                    obj=field_dt,
                    id="fields.W161",
                ),
                DjangoWarning(
                    "Fixed default value provided.",
                    hint="It seems you set a fixed date / time / datetime "
                    "value as default for this field. This may not be "
                    "what you want. If you want to have the current date "
                    "as default, use `django.utils.timezone.now`",
                    obj=field_d,
                    id="fields.W161",
                ),
            ],
        )

    @override_settings(USE_TZ=True)
    def test_fix_default_value_tz(self):
        self.test_fix_default_value()


@isolate_apps("invalid_models_tests")
class DecimalFieldTests(SimpleTestCase):
    def test_required_attributes(self):
        class Model(models.Model):
            field = models.DecimalField()

        field = Model._meta.get_field("field")
        self.assertEqual(
            field.check(),
            [
                Error(
                    "DecimalFields must define a 'decimal_places' attribute.",
                    obj=field,
                    id="fields.E130",
                ),
                Error(
                    "DecimalFields must define a 'max_digits' attribute.",
                    obj=field,
                    id="fields.E132",
                ),
            ],
        )

    def test_negative_max_digits_and_decimal_places(self):
        class Model(models.Model):
            field = models.DecimalField(max_digits=-1, decimal_places=-1)

        field = Model._meta.get_field("field")
        self.assertEqual(
            field.check(),
            [
                Error(
                    "'decimal_places' must be a non-negative integer.",
                    obj=field,
                    id="fields.E131",
                ),
                Error(
                    "'max_digits' must be a positive integer.",
                    obj=field,
                    id="fields.E133",
                ),
            ],
        )

    def test_bad_values_of_max_digits_and_decimal_places(self):
        class Model(models.Model):
            field = models.DecimalField(max_digits="bad", decimal_places="bad")

        field = Model._meta.get_field("field")
        self.assertEqual(
            field.check(),
            [
                Error(
                    "'decimal_places' must be a non-negative integer.",
                    obj=field,
                    id="fields.E131",
                ),
                Error(
                    "'max_digits' must be a positive integer.",
                    obj=field,
                    id="fields.E133",
                ),
            ],
        )

    def test_decimal_places_greater_than_max_digits(self):
        class Model(models.Model):
            field = models.DecimalField(max_digits=9, decimal_places=10)

        field = Model._meta.get_field("field")
        self.assertEqual(
            field.check(),
            [
                Error(
                    "'max_digits' must be greater or equal to 'decimal_places'.",
                    obj=field,
                    id="fields.E134",
                ),
            ],
        )

    def test_valid_field(self):
        class Model(models.Model):
            field = models.DecimalField(max_digits=10, decimal_places=10)

        field = Model._meta.get_field("field")
        self.assertEqual(field.check(), [])


@isolate_apps("invalid_models_tests")
class FileFieldTests(SimpleTestCase):
    def test_valid_default_case(self):
        class Model(models.Model):
            field = models.FileField()

        self.assertEqual(Model._meta.get_field("field").check(), [])

    def test_valid_case(self):
        class Model(models.Model):
            field = models.FileField(upload_to="somewhere")

        field = Model._meta.get_field("field")
        self.assertEqual(field.check(), [])

    def test_primary_key(self):
        class Model(models.Model):
            field = models.FileField(primary_key=False, upload_to="somewhere")

        field = Model._meta.get_field("field")
        self.assertEqual(
            field.check(),
            [
                Error(
                    "'primary_key' is not a valid argument for a FileField.",
                    obj=field,
                    id="fields.E201",
                )
            ],
        )

    def test_upload_to_starts_with_slash(self):
        class Model(models.Model):
            field = models.FileField(upload_to="/somewhere")

        field = Model._meta.get_field("field")
        self.assertEqual(
            field.check(),
            [
                Error(
                    "FileField's 'upload_to' argument must be a relative path, not "
                    "an absolute path.",
                    obj=field,
                    id="fields.E202",
                    hint="Remove the leading slash.",
                )
            ],
        )

    def test_upload_to_callable_not_checked(self):
        def callable(instance, filename):
            return "/" + filename

        class Model(models.Model):
            field = models.FileField(upload_to=callable)

        field = Model._meta.get_field("field")
        self.assertEqual(field.check(), [])


@isolate_apps("invalid_models_tests")
class FilePathFieldTests(SimpleTestCase):
    def test_forbidden_files_and_folders(self):
        class Model(models.Model):
            field = models.FilePathField(allow_files=False, allow_folders=False)

        field = Model._meta.get_field("field")
        self.assertEqual(
            field.check(),
            [
                Error(
                    "FilePathFields must have either 'allow_files' or 'allow_folders' "
                    "set to True.",
                    obj=field,
                    id="fields.E140",
                ),
            ],
        )


@isolate_apps("invalid_models_tests")
class GenericIPAddressFieldTests(SimpleTestCase):
    def test_non_nullable_blank(self):
        class Model(models.Model):
            field = models.GenericIPAddressField(null=False, blank=True)

        field = Model._meta.get_field("field")
        self.assertEqual(
            field.check(),
            [
                Error(
                    (
                        "GenericIPAddressFields cannot have blank=True if null=False, "
                        "as blank values are stored as nulls."
                    ),
                    obj=field,
                    id="fields.E150",
                ),
            ],
        )


@isolate_apps("invalid_models_tests")
class ImageFieldTests(SimpleTestCase):
    def test_pillow_installed(self):
        try:
            from PIL import Image  # NOQA
        except ImportError:
            pillow_installed = False
        else:
            pillow_installed = True

        class Model(models.Model):
            field = models.ImageField(upload_to="somewhere")

        field = Model._meta.get_field("field")
        errors = field.check()
        expected = (
            []
            if pillow_installed
            else [
                Error(
                    "Cannot use ImageField because Pillow is not installed.",
                    hint=(
                        "Get Pillow at https://pypi.org/project/Pillow/ "
                        'or run command "python -m pip install Pillow".'
                    ),
                    obj=field,
                    id="fields.E210",
                ),
            ]
        )
        self.assertEqual(errors, expected)


@isolate_apps("invalid_models_tests")
class IntegerFieldTests(SimpleTestCase):
    def test_max_length_warning(self):
        class Model(models.Model):
            integer = models.IntegerField(max_length=2)
            biginteger = models.BigIntegerField(max_length=2)
            smallinteger = models.SmallIntegerField(max_length=2)
            positiveinteger = models.PositiveIntegerField(max_length=2)
            positivebiginteger = models.PositiveBigIntegerField(max_length=2)
            positivesmallinteger = models.PositiveSmallIntegerField(max_length=2)

        for field in Model._meta.get_fields():
            if field.auto_created:
                continue
            with self.subTest(name=field.name):
                self.assertEqual(
                    field.check(),
                    [
                        DjangoWarning(
                            "'max_length' is ignored when used with %s."
                            % field.__class__.__name__,
                            hint="Remove 'max_length' from field",
                            obj=field,
                            id="fields.W122",
                        )
                    ],
                )


@isolate_apps("invalid_models_tests")
class TimeFieldTests(SimpleTestCase):
    maxDiff = None

    def test_fix_default_value(self):
        class Model(models.Model):
            field_dt = models.TimeField(default=now())
            field_t = models.TimeField(default=now().time())
            # Timezone-aware time object (when USE_TZ=True).
            field_tz = models.TimeField(default=now().timetz())
            field_now = models.DateField(default=now)

        names = ["field_dt", "field_t", "field_tz", "field_now"]
        fields = [Model._meta.get_field(name) for name in names]
        errors = []
        for field in fields:
            errors.extend(field.check())

        self.assertEqual(
            errors,
            [
                DjangoWarning(
                    "Fixed default value provided.",
                    hint="It seems you set a fixed date / time / datetime "
                    "value as default for this field. This may not be "
                    "what you want. If you want to have the current date "
                    "as default, use `django.utils.timezone.now`",
                    obj=fields[0],
                    id="fields.W161",
                ),
                DjangoWarning(
                    "Fixed default value provided.",
                    hint="It seems you set a fixed date / time / datetime "
                    "value as default for this field. This may not be "
                    "what you want. If you want to have the current date "
                    "as default, use `django.utils.timezone.now`",
                    obj=fields[1],
                    id="fields.W161",
                ),
                DjangoWarning(
                    "Fixed default value provided.",
                    hint=(
                        "It seems you set a fixed date / time / datetime value as "
                        "default for this field. This may not be what you want. "
                        "If you want to have the current date as default, use "
                        "`django.utils.timezone.now`"
                    ),
                    obj=fields[2],
                    id="fields.W161",
                ),
                # field_now doesn't raise a warning.
            ],
        )

    @override_settings(USE_TZ=True)
    def test_fix_default_value_tz(self):
        self.test_fix_default_value()


@isolate_apps("invalid_models_tests")
class TextFieldTests(TestCase):
    @skipIfDBFeature("supports_index_on_text_field")
    def test_max_length_warning(self):
        class Model(models.Model):
            value = models.TextField(db_index=True)

        field = Model._meta.get_field("value")
        field_type = field.db_type(connection)
        self.assertEqual(
            field.check(databases=self.databases),
            [
                DjangoWarning(
                    "%s does not support a database index on %s columns."
                    % (connection.display_name, field_type),
                    hint=(
                        "An index won't be created. Silence this warning if you "
                        "don't care about it."
                    ),
                    obj=field,
                    id="fields.W162",
                )
            ],
        )

    def test_db_collation(self):
        class Model(models.Model):
            field = models.TextField(db_collation="anything")

        field = Model._meta.get_field("field")
        error = Error(
            "%s does not support a database collation on TextFields."
            % connection.display_name,
            id="fields.E190",
            obj=field,
        )
        expected = (
            [] if connection.features.supports_collation_on_textfield else [error]
        )
        self.assertEqual(field.check(databases=self.databases), expected)

    def test_db_collation_required_db_features(self):
        class Model(models.Model):
            field = models.TextField(db_collation="anything")

            class Meta:
                required_db_features = {"supports_collation_on_textfield"}

        field = Model._meta.get_field("field")
        self.assertEqual(field.check(databases=self.databases), [])


@isolate_apps("invalid_models_tests")
class UUIDFieldTests(TestCase):
    def test_choices_named_group(self):
        class Model(models.Model):
            field = models.UUIDField(
                choices=[
                    [
                        "knights",
                        [
                            [
                                uuid.UUID("5c859437-d061-4847-b3f7-e6b78852f8c8"),
                                "Lancelot",
                            ],
                            [
                                uuid.UUID("c7853ec1-2ea3-4359-b02d-b54e8f1bcee2"),
                                "Galahad",
                            ],
                        ],
                    ],
                    [uuid.UUID("25d405be-4895-4d50-9b2e-d6695359ce47"), "Other"],
                ],
            )

        self.assertEqual(Model._meta.get_field("field").check(), [])


@isolate_apps("invalid_models_tests")
@skipUnlessDBFeature("supports_json_field")
class JSONFieldTests(TestCase):
    def test_invalid_default(self):
        class Model(models.Model):
            field = models.JSONField(default={})

        self.assertEqual(
            Model._meta.get_field("field").check(),
            [
                DjangoWarning(
                    msg=(
                        "JSONField default should be a callable instead of an "
                        "instance so that it's not shared between all field "
                        "instances."
                    ),
                    hint=("Use a callable instead, e.g., use `dict` instead of `{}`."),
                    obj=Model._meta.get_field("field"),
                    id="fields.E010",
                )
            ],
        )

    def test_valid_default(self):
        class Model(models.Model):
            field = models.JSONField(default=dict)

        self.assertEqual(Model._meta.get_field("field").check(), [])

    def test_valid_default_none(self):
        class Model(models.Model):
            field = models.JSONField(default=None)

        self.assertEqual(Model._meta.get_field("field").check(), [])

    def test_valid_callable_default(self):
        def callable_default():
            return {"it": "works"}

        class Model(models.Model):
            field = models.JSONField(default=callable_default)

        self.assertEqual(Model._meta.get_field("field").check(), [])


@isolate_apps("invalid_models_tests")
class DbCommentTests(TestCase):
    def test_db_comment(self):
        class Model(models.Model):
            field = models.IntegerField(db_comment="Column comment")

        errors = Model._meta.get_field("field").check(databases=self.databases)
        expected = (
            []
            if connection.features.supports_comments
            else [
                DjangoWarning(
                    f"{connection.display_name} does not support comments on columns "
                    f"(db_comment).",
                    obj=Model._meta.get_field("field"),
                    id="fields.W163",
                ),
            ]
        )
        self.assertEqual(errors, expected)

    def test_db_comment_required_db_features(self):
        class Model(models.Model):
            field = models.IntegerField(db_comment="Column comment")

            class Meta:
                required_db_features = {"supports_comments"}

        errors = Model._meta.get_field("field").check(databases=self.databases)
        self.assertEqual(errors, [])
