django-rest-framework/tests/test_fields.py

import datetime
import math
import os
import re
import uuid
import warnings
from decimal import ROUND_DOWN, ROUND_UP, Decimal
from enum import auto
from unittest.mock import patch
from zoneinfo import ZoneInfo

import pytest

try:
    import pytz
except ImportError:
    pytz = None

from django.core.exceptions import ValidationError as DjangoValidationError
from django.db.models import IntegerChoices, TextChoices
from django.http import QueryDict
from django.test import TestCase, override_settings
from django.utils.timezone import activate, deactivate, override

import rest_framework
from rest_framework import exceptions, serializers
from rest_framework.fields import (
    BuiltinSignatureError, DjangoImageField, SkipField, empty,
    is_simple_callable
)
from tests.models import UUIDForeignKeyTarget

utc = datetime.timezone.utc


# Tests for helper functions.
# ---------------------------


class TestIsSimpleCallable:

    def test_method(self):
        class Foo:
            @classmethod
            def classmethod(cls):
                pass

            def valid(self):
                pass

            def valid_kwargs(self, param="value"):
                pass

            def valid_vargs_kwargs(self, *args, **kwargs):
                pass

            def invalid(self, param):
                pass

        assert is_simple_callable(Foo.classmethod)

        # unbound methods
        assert not is_simple_callable(Foo.valid)
        assert not is_simple_callable(Foo.valid_kwargs)
        assert not is_simple_callable(Foo.valid_vargs_kwargs)
        assert not is_simple_callable(Foo.invalid)

        # bound methods
        assert is_simple_callable(Foo().valid)
        assert is_simple_callable(Foo().valid_kwargs)
        assert is_simple_callable(Foo().valid_vargs_kwargs)
        assert not is_simple_callable(Foo().invalid)

    def test_function(self):
        def simple():
            pass

        def valid(param="value", param2="value"):
            pass

        def valid_vargs_kwargs(*args, **kwargs):
            pass

        def invalid(param, param2="value"):
            pass

        assert is_simple_callable(simple)
        assert is_simple_callable(valid)
        assert is_simple_callable(valid_vargs_kwargs)
        assert not is_simple_callable(invalid)

    @pytest.mark.parametrize("obj", (True, None, "str", b"bytes", 123, 1.23))
    def test_not_callable(self, obj):
        assert not is_simple_callable(obj)

    def test_4602_regression(self):
        from django.db import models

        class ChoiceModel(models.Model):
            choice_field = models.CharField(
                max_length=1,
                default="a",
                choices=(("a", "A"), ("b", "B")),
            )

            class Meta:
                app_label = "tests"

        assert is_simple_callable(ChoiceModel().get_choice_field_display)

    def test_builtin_function(self):
        # Built-in function signatures are not easily inspectable, so the
        # current expectation is to just raise a helpful error message.
        timestamp = datetime.datetime.now()

        with pytest.raises(BuiltinSignatureError) as exc_info:
            is_simple_callable(timestamp.date)

        assert str(exc_info.value) == (
            "Built-in function signatures are not inspectable. Wrap the "
            "function call in a simple, pure Python function."
        )

    def test_type_annotation(self):
        # The annotation will otherwise raise a syntax error in python < 3.5
        locals = {}
        exec("def valid(param: str='value'):  pass", locals)
        valid = locals["valid"]

        assert is_simple_callable(valid)


# Tests for field keyword arguments and core functionality.
# ---------------------------------------------------------


class TestEmpty:
    """
    Tests for `required`, `allow_null`, `allow_blank`, `default`.
    """

    def test_required(self):
        """
        By default a field must be included in the input.
        """
        field = serializers.IntegerField()
        with pytest.raises(serializers.ValidationError) as exc_info:
            field.run_validation()
        assert exc_info.value.detail == ["This field is required."]

    def test_not_required(self):
        """
        If `required=False` then a field may be omitted from the input.
        """
        field = serializers.IntegerField(required=False)
        with pytest.raises(serializers.SkipField):
            field.run_validation()

    def test_disallow_null(self):
        """
        By default `None` is not a valid input.
        """
        field = serializers.IntegerField()
        with pytest.raises(serializers.ValidationError) as exc_info:
            field.run_validation(None)
        assert exc_info.value.detail == ["This field may not be null."]

    def test_allow_null(self):
        """
        If `allow_null=True` then `None` is a valid input.
        """
        field = serializers.IntegerField(allow_null=True)
        output = field.run_validation(None)
        assert output is None

    def test_disallow_blank(self):
        """
        By default '' is not a valid input.
        """
        field = serializers.CharField()
        with pytest.raises(serializers.ValidationError) as exc_info:
            field.run_validation("")
        assert exc_info.value.detail == ["This field may not be blank."]

    def test_allow_blank(self):
        """
        If `allow_blank=True` then '' is a valid input.
        """
        field = serializers.CharField(allow_blank=True)
        output = field.run_validation("")
        assert output == ""

    def test_default(self):
        """
        If `default` is set, then omitted values get the default input.
        """
        field = serializers.IntegerField(default=123)
        output = field.run_validation()
        assert output == 123


class TestSource:
    def test_source(self):
        class ExampleSerializer(serializers.Serializer):
            example_field = serializers.CharField(source="other")

        serializer = ExampleSerializer(data={"example_field": "abc"})
        assert serializer.is_valid()
        assert serializer.validated_data == {"other": "abc"}

    def test_redundant_source(self):
        class ExampleSerializer(serializers.Serializer):
            example_field = serializers.CharField(source="example_field")

        with pytest.raises(AssertionError) as exc_info:
            ExampleSerializer().fields
        assert str(exc_info.value) == (
            "It is redundant to specify `source='example_field'` on field "
            "'CharField' in serializer 'ExampleSerializer', because it is the "
            "same as the field name. Remove the `source` keyword argument."
        )

    def test_callable_source(self):
        class ExampleSerializer(serializers.Serializer):
            example_field = serializers.CharField(source="example_callable")

        class ExampleInstance:
            def example_callable(self):
                return "example callable value"

        serializer = ExampleSerializer(ExampleInstance())
        assert serializer.data["example_field"] == "example callable value"

    def test_callable_source_raises(self):
        class ExampleSerializer(serializers.Serializer):
            example_field = serializers.CharField(
                source="example_callable", read_only=True
            )

        class ExampleInstance:
            def example_callable(self):
                raise AttributeError("method call failed")

        with pytest.raises(ValueError) as exc_info:
            serializer = ExampleSerializer(ExampleInstance())
            serializer.data.items()

        assert "method call failed" in str(exc_info.value)

    def test_builtin_callable_source_raises(self):
        class BuiltinSerializer(serializers.Serializer):
            date = serializers.ReadOnlyField(source="timestamp.date")

        with pytest.raises(BuiltinSignatureError) as exc_info:
            BuiltinSerializer({"timestamp": datetime.datetime.now()}).data

        assert str(exc_info.value) == (
            "Field source for `BuiltinSerializer.date` maps to a built-in "
            "function type and is invalid. Define a property or method on "
            "the `dict` instance that wraps the call to the built-in function."
        )


class TestReadOnly:
    def setup_method(self):
        class TestSerializer(serializers.Serializer):
            read_only = serializers.ReadOnlyField(default="789")
            writable = serializers.IntegerField()

        self.Serializer = TestSerializer

    def test_writable_fields(self):
        """
        Read-only fields should not be writable, even with default ()
        """
        serializer = self.Serializer()
        assert len(list(serializer._writable_fields)) == 1

    def test_validate_read_only(self):
        """
        Read-only serializers.should not be included in validation.
        """
        data = {"read_only": 123, "writable": 456}
        serializer = self.Serializer(data=data)
        assert serializer.is_valid()
        assert serializer.validated_data == {"writable": 456}

    def test_serialize_read_only(self):
        """
        Read-only serializers.should be serialized.
        """
        instance = {"read_only": 123, "writable": 456}
        serializer = self.Serializer(instance)
        assert serializer.data == {"read_only": 123, "writable": 456}


class TestWriteOnly:
    def setup_method(self):
        class TestSerializer(serializers.Serializer):
            write_only = serializers.IntegerField(write_only=True)
            readable = serializers.IntegerField()

        self.Serializer = TestSerializer

    def test_validate_write_only(self):
        """
        Write-only serializers.should be included in validation.
        """
        data = {"write_only": 123, "readable": 456}
        serializer = self.Serializer(data=data)
        assert serializer.is_valid()
        assert serializer.validated_data == {"write_only": 123, "readable": 456}

    def test_serialize_write_only(self):
        """
        Write-only serializers.should not be serialized.
        """
        instance = {"write_only": 123, "readable": 456}
        serializer = self.Serializer(instance)
        assert serializer.data == {"readable": 456}


class TestInitial:
    def setup_method(self):
        class TestSerializer(serializers.Serializer):
            initial_field = serializers.IntegerField(initial=123)
            blank_field = serializers.IntegerField()

        self.serializer = TestSerializer()

    def test_initial(self):
        """
        Initial values should be included when serializing a new representation.
        """
        assert self.serializer.data == {"initial_field": 123, "blank_field": None}


class TestInitialWithCallable:
    def setup_method(self):
        def initial_value():
            return 123

        class TestSerializer(serializers.Serializer):
            initial_field = serializers.IntegerField(initial=initial_value)

        self.serializer = TestSerializer()

    def test_initial_should_accept_callable(self):
        """
        Follows the default ``Field.initial`` behaviour where they accept a
        callable to produce the initial value"""
        assert self.serializer.data == {
            "initial_field": 123,
        }


class TestLabel:
    def setup_method(self):
        class TestSerializer(serializers.Serializer):
            labeled = serializers.IntegerField(label="My label")

        self.serializer = TestSerializer()

    def test_label(self):
        """
        A field's label may be set with the `label` argument.
        """
        fields = self.serializer.fields
        assert fields["labeled"].label == "My label"


class TestInvalidErrorKey:
    def setup_method(self):
        class ExampleField(serializers.Field):
            def to_native(self, data):
                self.fail("incorrect")

        self.field = ExampleField()

    def test_invalid_error_key(self):
        """
        If a field raises a validation error, but does not have a corresponding
        error message, then raise an appropriate assertion error.
        """
        with pytest.raises(AssertionError) as exc_info:
            self.field.to_native(123)
        expected = (
            "ValidationError raised by `ExampleField`, but error key "
            "`incorrect` does not exist in the `error_messages` dictionary."
        )
        assert str(exc_info.value) == expected


class TestBooleanHTMLInput:
    def test_empty_html_checkbox(self):
        """
        HTML checkboxes do not send any value, but should be treated
        as `False` by BooleanField if allow_null=False.
        """

        class TestSerializer(serializers.Serializer):
            archived = serializers.BooleanField()

        serializer = TestSerializer(data=QueryDict(""))
        assert serializer.is_valid()
        assert serializer.validated_data == {"archived": False}

    def test_empty_html_checkbox_not_required(self):
        """
        HTML checkboxes do not send any value, but should be treated
        as `False` by BooleanField when the field is required=False
        and allow_null=False.
        """

        class TestSerializer(serializers.Serializer):
            archived = serializers.BooleanField(required=False)

        serializer = TestSerializer(data=QueryDict(""))
        assert serializer.is_valid()
        assert serializer.validated_data == {"archived": False}

    def test_empty_html_checkbox_allow_null(self):
        """
        HTML checkboxes do not send any value and should be treated
        as `None` by BooleanField if allow_null is True.
        """

        class TestSerializer(serializers.Serializer):
            archived = serializers.BooleanField(allow_null=True)

        serializer = TestSerializer(data=QueryDict(""))
        assert serializer.is_valid()
        assert serializer.validated_data == {"archived": None}

    def test_empty_html_checkbox_allow_null_with_default(self):
        """
        BooleanField should respect default if set and still allow
        setting null values.
        """

        class TestSerializer(serializers.Serializer):
            archived = serializers.BooleanField(allow_null=True, default=True)

        serializer = TestSerializer(data=QueryDict(""))
        assert serializer.is_valid()
        assert serializer.validated_data == {"archived": True}

        serializer = TestSerializer(data=QueryDict("archived="))
        assert serializer.is_valid()
        assert serializer.validated_data == {"archived": None}


class TestHTMLInput:
    def test_empty_html_charfield_with_default(self):
        class TestSerializer(serializers.Serializer):
            message = serializers.CharField(default="happy")

        serializer = TestSerializer(data=QueryDict(""))
        assert serializer.is_valid()
        assert serializer.validated_data == {"message": "happy"}

    def test_empty_html_charfield_without_default(self):
        class TestSerializer(serializers.Serializer):
            message = serializers.CharField(allow_blank=True)

        serializer = TestSerializer(data=QueryDict("message="))
        assert serializer.is_valid()
        assert serializer.validated_data == {"message": ""}

    def test_empty_html_charfield_without_default_not_required(self):
        class TestSerializer(serializers.Serializer):
            message = serializers.CharField(allow_blank=True, required=False)

        serializer = TestSerializer(data=QueryDict("message="))
        assert serializer.is_valid()
        assert serializer.validated_data == {"message": ""}

    def test_empty_html_integerfield(self):
        class TestSerializer(serializers.Serializer):
            message = serializers.IntegerField(default=123)

        serializer = TestSerializer(data=QueryDict("message="))
        assert serializer.is_valid()
        assert serializer.validated_data == {"message": 123}

    def test_empty_html_uuidfield_with_default(self):
        class TestSerializer(serializers.Serializer):
            message = serializers.UUIDField(default=uuid.uuid4)

        serializer = TestSerializer(data=QueryDict("message="))
        assert serializer.is_valid()
        assert list(serializer.validated_data) == ["message"]

    def test_empty_html_uuidfield_with_optional(self):
        class TestSerializer(serializers.Serializer):
            message = serializers.UUIDField(required=False)

        serializer = TestSerializer(data=QueryDict("message="))
        assert serializer.is_valid()
        assert list(serializer.validated_data) == []

    def test_empty_html_charfield_allow_null(self):
        class TestSerializer(serializers.Serializer):
            message = serializers.CharField(allow_null=True)

        serializer = TestSerializer(data=QueryDict("message="))
        assert serializer.is_valid()
        assert serializer.validated_data == {"message": None}

    def test_empty_html_datefield_allow_null(self):
        class TestSerializer(serializers.Serializer):
            expiry = serializers.DateField(allow_null=True)

        serializer = TestSerializer(data=QueryDict("expiry="))
        assert serializer.is_valid()
        assert serializer.validated_data == {"expiry": None}

    def test_empty_html_charfield_allow_null_allow_blank(self):
        class TestSerializer(serializers.Serializer):
            message = serializers.CharField(allow_null=True, allow_blank=True)

        serializer = TestSerializer(data=QueryDict("message="))
        assert serializer.is_valid()
        assert serializer.validated_data == {"message": ""}

    def test_empty_html_charfield_required_false(self):
        class TestSerializer(serializers.Serializer):
            message = serializers.CharField(required=False)

        serializer = TestSerializer(data=QueryDict(""))
        assert serializer.is_valid()
        assert serializer.validated_data == {}

    def test_querydict_list_input(self):
        class TestSerializer(serializers.Serializer):
            scores = serializers.ListField(child=serializers.IntegerField())

        serializer = TestSerializer(data=QueryDict("scores=1&scores=3"))
        assert serializer.is_valid()
        assert serializer.validated_data == {"scores": [1, 3]}

    def test_querydict_list_input_only_one_input(self):
        class TestSerializer(serializers.Serializer):
            scores = serializers.ListField(child=serializers.IntegerField())

        serializer = TestSerializer(data=QueryDict("scores=1&"))
        assert serializer.is_valid()
        assert serializer.validated_data == {"scores": [1]}

    def test_querydict_list_input_no_values_uses_default(self):
        """
        When there are no values passed in, and default is set
        The field should return the default value
        """

        class TestSerializer(serializers.Serializer):
            a = serializers.IntegerField(required=True)
            scores = serializers.ListField(default=lambda: [1, 3])

        serializer = TestSerializer(data=QueryDict("a=1&"))
        assert serializer.is_valid()
        assert serializer.validated_data == {"a": 1, "scores": [1, 3]}

    def test_querydict_list_input_supports_indexed_keys(self):
        """
        When data is passed in the format `scores[0]=1&scores[1]=3`
        The field should return the correct list, ignoring the default
        """

        class TestSerializer(serializers.Serializer):
            scores = serializers.ListField(default=lambda: [1, 3])

        serializer = TestSerializer(data=QueryDict("scores[0]=5&scores[1]=6"))
        assert serializer.is_valid()
        assert serializer.validated_data == {"scores": ["5", "6"]}

    def test_querydict_list_input_no_values_no_default_and_not_required(self):
        """
        When there are no keys passed, there is no default, and required=False
        The field should be skipped
        """

        class TestSerializer(serializers.Serializer):
            scores = serializers.ListField(required=False)

        serializer = TestSerializer(data=QueryDict(""))
        assert serializer.is_valid()
        assert serializer.validated_data == {}

    def test_querydict_list_input_posts_key_but_no_values(self):
        """
        When there are no keys passed, there is no default, and required=False
        The field should return an array of 1 item, blank
        """

        class TestSerializer(serializers.Serializer):
            scores = serializers.ListField(required=False)

        serializer = TestSerializer(data=QueryDict("scores=&"))
        assert serializer.is_valid()
        assert serializer.validated_data == {"scores": [""]}


class TestCreateOnlyDefault:
    def setup_method(self):
        default = serializers.CreateOnlyDefault("2001-01-01")

        class TestSerializer(serializers.Serializer):
            published = serializers.HiddenField(default=default)
            text = serializers.CharField()

        self.Serializer = TestSerializer

    def test_create_only_default_is_provided(self):
        serializer = self.Serializer(data={"text": "example"})
        assert serializer.is_valid()
        assert serializer.validated_data == {
            "text": "example",
            "published": "2001-01-01",
        }

    def test_create_only_default_is_not_provided_on_update(self):
        instance = {"text": "example", "published": "2001-01-01"}
        serializer = self.Serializer(instance, data={"text": "example"})
        assert serializer.is_valid()
        assert serializer.validated_data == {
            "text": "example",
        }

    def test_create_only_default_callable_sets_context(self):
        """
        CreateOnlyDefault instances with a callable default should set context
        on the callable if possible
        """

        class TestCallableDefault:
            requires_context = True

            def __call__(self, field=None):
                return "success" if field is not None else "failure"

        class TestSerializer(serializers.Serializer):
            context_set = serializers.CharField(
                default=serializers.CreateOnlyDefault(TestCallableDefault())
            )

        serializer = TestSerializer(data={})
        assert serializer.is_valid()
        assert serializer.validated_data["context_set"] == "success"


class Test5087Regression:
    def test_parent_binding(self):
        parent = serializers.Serializer()
        field = serializers.CharField()

        assert field.root is field
        field.bind("name", parent)
        assert field.root is parent


class TestTyping(TestCase):
    def test_field_is_subscriptable(self):
        assert serializers.Field is serializers.Field["foo"]


# Tests for field input and output values.
# ----------------------------------------


def get_items(mapping_or_list_of_two_tuples):
    # Tests accept either lists of two tuples, or dictionaries.
    if isinstance(mapping_or_list_of_two_tuples, dict):
        # {value: expected}
        return mapping_or_list_of_two_tuples.items()
    # [(value, expected), ...]
    return mapping_or_list_of_two_tuples


class FieldValues:
    """
    Base class for testing valid and invalid input values.
    """

    def test_valid_inputs(self, *args):
        """
        Ensure that valid values return the expected validated data.
        """
        for input_value, expected_output in get_items(self.valid_inputs):
            assert (
                self.field.run_validation(input_value) == expected_output
            ), f"input value: {repr(input_value)}"

    def test_invalid_inputs(self, *args):
        """
        Ensure that invalid values raise the expected validation error.
        """
        for input_value, expected_failure in get_items(self.invalid_inputs):
            with pytest.raises(serializers.ValidationError) as exc_info:
                self.field.run_validation(input_value)
            assert (
                exc_info.value.detail == expected_failure
            ), f"input value: {repr(input_value)}"

    def test_outputs(self, *args):
        for output_value, expected_output in get_items(self.outputs):
            assert (
                self.field.to_representation(output_value) == expected_output
            ), f"output value: {repr(output_value)}"


# Boolean types...


class TestBooleanField(FieldValues):
    """
    Valid and invalid values for `BooleanField`.
    """

    valid_inputs = {
        "True": True,
        "TRUE": True,
        "tRuE": True,
        "t": True,
        "T": True,
        "true": True,
        "on": True,
        "ON": True,
        "oN": True,
        "False": False,
        "FALSE": False,
        "fALse": False,
        "f": False,
        "F": False,
        "false": False,
        "off": False,
        "OFF": False,
        "oFf": False,
        "1": True,
        "0": False,
        1: True,
        0: False,
        True: True,
        False: False,
    }
    invalid_inputs = {
        "foo": ["Must be a valid boolean."],
        None: ["This field may not be null."],
    }
    outputs = {
        "True": True,
        "TRUE": True,
        "tRuE": True,
        "t": True,
        "T": True,
        "true": True,
        "on": True,
        "ON": True,
        "oN": True,
        "False": False,
        "FALSE": False,
        "fALse": False,
        "f": False,
        "F": False,
        "false": False,
        "off": False,
        "OFF": False,
        "oFf": False,
        "1": True,
        "0": False,
        1: True,
        0: False,
        True: True,
        False: False,
        "other": True,
    }
    field = serializers.BooleanField()

    def test_disallow_unhashable_collection_types(self):
        inputs = (
            [],
            {},
        )
        field = self.field
        for input_value in inputs:
            with pytest.raises(serializers.ValidationError) as exc_info:
                field.run_validation(input_value)
            expected = ["Must be a valid boolean."]
            assert exc_info.value.detail == expected


class TestNullableBooleanField(TestBooleanField):
    """
    Valid and invalid values for `BooleanField` when `allow_null=True`.
    """

    valid_inputs = {
        "true": True,
        "false": False,
        "null": None,
        True: True,
        False: False,
        None: None,
    }
    invalid_inputs = {
        "foo": ["Must be a valid boolean."],
    }
    outputs = {
        "true": True,
        "false": False,
        "null": None,
        True: True,
        False: False,
        None: None,
        "other": True,
    }
    field = serializers.BooleanField(allow_null=True)


# String types...


class TestCharField(FieldValues):
    """
    Valid and invalid values for `CharField`.
    """

    valid_inputs = {1: "1", "abc": "abc"}
    invalid_inputs = {
        (): ["Not a valid string."],
        True: ["Not a valid string."],
        "": ["This field may not be blank."],
    }
    outputs = {1: "1", "abc": "abc"}
    field = serializers.CharField()

    def test_trim_whitespace_default(self):
        field = serializers.CharField()
        assert field.to_internal_value(" abc ") == "abc"

    def test_trim_whitespace_disabled(self):
        field = serializers.CharField(trim_whitespace=False)
        assert field.to_internal_value(" abc ") == " abc "

    def test_disallow_blank_with_trim_whitespace(self):
        field = serializers.CharField(allow_blank=False, trim_whitespace=True)

        with pytest.raises(serializers.ValidationError) as exc_info:
            field.run_validation("   ")
        assert exc_info.value.detail == ["This field may not be blank."]

    def test_null_bytes(self):
        field = serializers.CharField()

        for value in ("\0", "foo\0", "\0foo", "foo\0foo"):
            with pytest.raises(serializers.ValidationError) as exc_info:
                field.run_validation(value)
            assert exc_info.value.detail == ["Null characters are not allowed."]

    def test_surrogate_characters(self):
        field = serializers.CharField()

        for code_point, expected_message in (
            (0xD800, "Surrogate characters are not allowed: U+D800."),
            (0xDFFF, "Surrogate characters are not allowed: U+DFFF."),
        ):
            with pytest.raises(serializers.ValidationError) as exc_info:
                field.run_validation(chr(code_point))
            assert exc_info.value.detail[0].code == "surrogate_characters_not_allowed"
            assert str(exc_info.value.detail[0]) == expected_message

        for code_point in (0xD800 - 1, 0xDFFF + 1):
            field.run_validation(chr(code_point))

    def test_iterable_validators(self):
        """
        Ensure `validators` parameter is compatible with reasonable iterables.
        """
        value = "example"

        for validators in ([], (), set()):
            field = serializers.CharField(validators=validators)
            field.run_validation(value)

        def raise_exception(value):
            raise exceptions.ValidationError("Raised error")

        for validators in ([raise_exception], (raise_exception,), {raise_exception}):
            field = serializers.CharField(validators=validators)
            with pytest.raises(serializers.ValidationError) as exc_info:
                field.run_validation(value)
            assert exc_info.value.detail == ["Raised error"]


class TestEmailField(FieldValues):
    """
    Valid and invalid values for `EmailField`.
    """

    valid_inputs = {
        "example@example.com": "example@example.com",
        " example@example.com ": "example@example.com",
    }
    invalid_inputs = {"examplecom": ["Enter a valid email address."]}
    outputs = {}
    field = serializers.EmailField()


class TestRegexField(FieldValues):
    """
    Valid and invalid values for `RegexField`.
    """

    valid_inputs = {
        "a9": "a9",
    }
    invalid_inputs = {"A9": ["This value does not match the required pattern."]}
    outputs = {}
    field = serializers.RegexField(regex="[a-z][0-9]")


class TestiCompiledRegexField(FieldValues):
    """
    Valid and invalid values for `RegexField`.
    """

    valid_inputs = {
        "a9": "a9",
    }
    invalid_inputs = {"A9": ["This value does not match the required pattern."]}
    outputs = {}
    field = serializers.RegexField(regex=re.compile("[a-z][0-9]"))


class TestSlugField(FieldValues):
    """
    Valid and invalid values for `SlugField`.
    """

    valid_inputs = {
        "slug-99": "slug-99",
    }
    invalid_inputs = {
        "slug 99": [
            'Enter a valid "slug" consisting of letters, numbers, underscores or hyphens.'
        ]
    }
    outputs = {}
    field = serializers.SlugField()

    def test_allow_unicode_true(self):
        field = serializers.SlugField(allow_unicode=True)

        validation_error = False
        try:
            field.run_validation("slug-99-\u0420")
        except serializers.ValidationError:
            validation_error = True

        assert not validation_error


class TestURLField(FieldValues):
    """
    Valid and invalid values for `URLField`.
    """

    valid_inputs = {
        "http://example.com": "http://example.com",
    }
    invalid_inputs = {"example.com": ["Enter a valid URL."]}
    outputs = {}
    field = serializers.URLField()


class TestUUIDField(FieldValues):
    """
    Valid and invalid values for `UUIDField`.
    """

    valid_inputs = {
        "825d7aeb-05a9-45b5-a5b7-05df87923cda": uuid.UUID(
            "825d7aeb-05a9-45b5-a5b7-05df87923cda"
        ),
        "825d7aeb05a945b5a5b705df87923cda": uuid.UUID(
            "825d7aeb-05a9-45b5-a5b7-05df87923cda"
        ),
        "urn:uuid:213b7d9b-244f-410d-828c-dabce7a2615d": uuid.UUID(
            "213b7d9b-244f-410d-828c-dabce7a2615d"
        ),
        284758210125106368185219588917561929842: uuid.UUID(
            "d63a6fb6-88d5-40c7-a91c-9edf73283072"
        ),
    }
    invalid_inputs = {
        "825d7aeb-05a9-45b5-a5b7": ["Must be a valid UUID."],
        (1, 2, 3): ["Must be a valid UUID."],
    }
    outputs = {
        uuid.UUID(
            "825d7aeb-05a9-45b5-a5b7-05df87923cda"
        ): "825d7aeb-05a9-45b5-a5b7-05df87923cda"
    }
    field = serializers.UUIDField()

    def _test_format(self, uuid_format, formatted_uuid_0):
        field = serializers.UUIDField(format=uuid_format)
        assert field.to_representation(uuid.UUID(int=0)) == formatted_uuid_0
        assert field.to_internal_value(formatted_uuid_0) == uuid.UUID(int=0)

    def test_formats(self):
        self._test_format("int", 0)
        self._test_format("hex_verbose", "00000000-0000-0000-0000-000000000000")
        self._test_format("urn", "urn:uuid:00000000-0000-0000-0000-000000000000")
        self._test_format("hex", "0" * 32)


class TestIPAddressField(FieldValues):
    """
    Valid and invalid values for `IPAddressField`
    """

    valid_inputs = {
        "127.0.0.1": "127.0.0.1",
        "192.168.33.255": "192.168.33.255",
        "2001:0db8:85a3:0042:1000:8a2e:0370:7334": "2001:db8:85a3:42:1000:8a2e:370:7334",
        "2001:cdba:0:0:0:0:3257:9652": "2001:cdba::3257:9652",
        "2001:cdba::3257:9652": "2001:cdba::3257:9652",
    }
    invalid_inputs = {
        "127001": ["Enter a valid IPv4 or IPv6 address."],
        "127.122.111.2231": ["Enter a valid IPv4 or IPv6 address."],
        "2001:::9652": ["Enter a valid IPv4 or IPv6 address."],
        "2001:0db8:85a3:0042:1000:8a2e:0370:73341": [
            "Enter a valid IPv4 or IPv6 address."
        ],
        1000: ["Enter a valid IPv4 or IPv6 address."],
    }
    outputs = {}
    field = serializers.IPAddressField()


class TestIPv4AddressField(FieldValues):
    """
    Valid and invalid values for `IPAddressField`
    """

    valid_inputs = {
        "127.0.0.1": "127.0.0.1",
        "192.168.33.255": "192.168.33.255",
    }
    invalid_inputs = {
        "127001": ["Enter a valid IPv4 address."],
        "127.122.111.2231": ["Enter a valid IPv4 address."],
    }
    outputs = {}
    field = serializers.IPAddressField(protocol="IPv4")


class TestIPv6AddressField(FieldValues):
    """
    Valid and invalid values for `IPAddressField`
    """

    valid_inputs = {
        "2001:0db8:85a3:0042:1000:8a2e:0370:7334": "2001:db8:85a3:42:1000:8a2e:370:7334",
        "2001:cdba:0:0:0:0:3257:9652": "2001:cdba::3257:9652",
        "2001:cdba::3257:9652": "2001:cdba::3257:9652",
    }
    invalid_inputs = {
        "2001:::9652": ["Enter a valid IPv4 or IPv6 address."],
        "2001:0db8:85a3:0042:1000:8a2e:0370:73341": [
            "Enter a valid IPv4 or IPv6 address."
        ],
    }
    outputs = {}
    field = serializers.IPAddressField(protocol="IPv6")


class TestFilePathField(FieldValues):
    """
    Valid and invalid values for `FilePathField`
    """

    valid_inputs = {
        __file__: __file__,
    }
    invalid_inputs = {"wrong_path": ['"wrong_path" is not a valid path choice.']}
    outputs = {}
    field = serializers.FilePathField(path=os.path.abspath(os.path.dirname(__file__)))


# Number types...


class TestIntegerField(FieldValues):
    """
    Valid and invalid values for `IntegerField`.
    """

    valid_inputs = {"1": 1, "0": 0, 1: 1, 0: 0, 1.0: 1, 0.0: 0, "1.0": 1}
    invalid_inputs = {
        0.5: ["A valid integer is required."],
        "abc": ["A valid integer is required."],
        "0.5": ["A valid integer is required."],
    }
    outputs = {"1": 1, "0": 0, 1: 1, 0: 0, 1.0: 1, 0.0: 0}
    field = serializers.IntegerField()


class TestMinMaxIntegerField(FieldValues):
    """
    Valid and invalid values for `IntegerField` with min and max limits.
    """

    valid_inputs = {
        "1": 1,
        "3": 3,
        1: 1,
        3: 3,
    }
    invalid_inputs = {
        0: ["Ensure this value is greater than or equal to 1."],
        4: ["Ensure this value is less than or equal to 3."],
        "0": ["Ensure this value is greater than or equal to 1."],
        "4": ["Ensure this value is less than or equal to 3."],
    }
    outputs = {}
    field = serializers.IntegerField(min_value=1, max_value=3)


class TestFloatField(FieldValues):
    """
    Valid and invalid values for `FloatField`.
    """

    valid_inputs = {
        "1": 1.0,
        "0": 0.0,
        1: 1.0,
        0: 0.0,
        1.0: 1.0,
        0.0: 0.0,
    }
    invalid_inputs = {"abc": ["A valid number is required."]}
    outputs = {
        "1": 1.0,
        "0": 0.0,
        1: 1.0,
        0: 0.0,
        1.0: 1.0,
        0.0: 0.0,
    }
    field = serializers.FloatField()


class TestMinMaxFloatField(FieldValues):
    """
    Valid and invalid values for `FloatField` with min and max limits.
    """

    valid_inputs = {
        "1": 1,
        "3": 3,
        1: 1,
        3: 3,
        1.0: 1.0,
        3.0: 3.0,
    }
    invalid_inputs = {
        0.9: ["Ensure this value is greater than or equal to 1."],
        3.1: ["Ensure this value is less than or equal to 3."],
        "0.0": ["Ensure this value is greater than or equal to 1."],
        "3.1": ["Ensure this value is less than or equal to 3."],
    }
    outputs = {}
    field = serializers.FloatField(min_value=1, max_value=3)


class TestFloatFieldOverFlowError(TestCase):
    def test_overflow_error_float_field(self):
        field = serializers.FloatField()
        with pytest.raises(serializers.ValidationError) as exec_info:
            field.to_internal_value(data=math.factorial(171))
        assert "Integer value too large to convert to float" in str(
            exec_info.value.detail
        )


class TestDecimalField(FieldValues):
    """
    Valid and invalid values for `DecimalField`.
    """

    valid_inputs = {
        "12.3": Decimal("12.3"),
        "0.1": Decimal("0.1"),
        10: Decimal("10"),
        0: Decimal("0"),
        12.3: Decimal("12.3"),
        0.1: Decimal("0.1"),
        "2E+1": Decimal("20"),
    }
    invalid_inputs = (
        (None, ["This field may not be null."]),
        ("", ["A valid number is required."]),
        (" ", ["A valid number is required."]),
        ("abc", ["A valid number is required."]),
        (Decimal("Nan"), ["A valid number is required."]),
        (Decimal("Snan"), ["A valid number is required."]),
        (Decimal("Inf"), ["A valid number is required."]),
        ("12.345", ["Ensure that there are no more than 3 digits in total."]),
        (200000000000.0, ["Ensure that there are no more than 3 digits in total."]),
        ("0.01", ["Ensure that there are no more than 1 decimal places."]),
        (
            123,
            ["Ensure that there are no more than 2 digits before the decimal point."],
        ),
        (
            "2E+2",
            ["Ensure that there are no more than 2 digits before the decimal point."],
        ),
    )
    outputs = {
        "1": "1.0",
        "0": "0.0",
        "1.09": "1.1",
        "0.04": "0.0",
        1: "1.0",
        0: "0.0",
        Decimal("1.0"): "1.0",
        Decimal("0.0"): "0.0",
        Decimal("1.09"): "1.1",
        Decimal("0.04"): "0.0",
    }
    field = serializers.DecimalField(max_digits=3, decimal_places=1)


class TestAllowNullDecimalField(FieldValues):
    valid_inputs = {
        None: None,
        "": None,
        " ": None,
    }
    invalid_inputs = {}
    outputs = {
        None: "",
    }
    field = serializers.DecimalField(max_digits=3, decimal_places=1, allow_null=True)


class TestAllowNullNoStringCoercionDecimalField(FieldValues):
    valid_inputs = {
        None: None,
        "": None,
        " ": None,
    }
    invalid_inputs = {}
    outputs = {
        None: None,
    }
    field = serializers.DecimalField(
        max_digits=3, decimal_places=1, allow_null=True, coerce_to_string=False
    )


class TestMinMaxDecimalField(FieldValues):
    """
    Valid and invalid values for `DecimalField` with min and max limits.
    """

    valid_inputs = {
        "10.0": Decimal("10.0"),
        "20.0": Decimal("20.0"),
    }
    invalid_inputs = {
        "9.9": ["Ensure this value is greater than or equal to 10.0."],
        "20.1": ["Ensure this value is less than or equal to 20.0."],
    }
    outputs = {}
    field = serializers.DecimalField(
        max_digits=3, decimal_places=1, min_value=10.0, max_value=20.0
    )

    def test_warning_when_not_decimal_types(self, caplog):
        with warnings.catch_warnings(record=True) as w:
            warnings.simplefilter("always")

            serializers.DecimalField(
                max_digits=3, decimal_places=1, min_value=10.0, max_value=20.0
            )

            assert len(w) == 2
            assert all(issubclass(i.category, UserWarning) for i in w)

            assert "max_value should be an integer or Decimal instance" in str(
                w[0].message
            )
            assert "min_value should be an integer or Decimal instance" in str(
                w[1].message
            )


class TestAllowEmptyStrDecimalFieldWithValidators(FieldValues):
    """
    Check that empty string ('', ' ') is acceptable value for the DecimalField
    if allow_null=True and there are max/min validators
    """

    valid_inputs = {
        None: None,
        "": None,
        " ": None,
        "  ": None,
        5: Decimal("5"),
        "0": Decimal("0"),
        "10": Decimal("10"),
    }
    invalid_inputs = {
        -1: ["Ensure this value is greater than or equal to 0."],
        11: ["Ensure this value is less than or equal to 10."],
    }
    outputs = {
        None: "",
    }
    field = serializers.DecimalField(
        max_digits=3, decimal_places=1, allow_null=True, min_value=0, max_value=10
    )


class TestNoMaxDigitsDecimalField(FieldValues):
    field = serializers.DecimalField(
        max_value=100, min_value=0, decimal_places=2, max_digits=None
    )
    valid_inputs = {"10": Decimal("10.00")}
    invalid_inputs = {}
    outputs = {}


class TestNoStringCoercionDecimalField(FieldValues):
    """
    Output values for `DecimalField` with `coerce_to_string=False`.
    """

    valid_inputs = {}
    invalid_inputs = {}
    outputs = {
        1.09: Decimal("1.1"),
        0.04: Decimal("0.0"),
        "1.09": Decimal("1.1"),
        "0.04": Decimal("0.0"),
        Decimal("1.09"): Decimal("1.1"),
        Decimal("0.04"): Decimal("0.0"),
    }
    field = serializers.DecimalField(
        max_digits=3, decimal_places=1, coerce_to_string=False
    )


class TestLocalizedDecimalField(TestCase):
    @override_settings(LANGUAGE_CODE="pl")
    def test_to_internal_value(self):
        field = serializers.DecimalField(max_digits=2, decimal_places=1, localize=True)
        assert field.to_internal_value("1,1") == Decimal("1.1")

    @override_settings(LANGUAGE_CODE="pl")
    def test_to_representation(self):
        field = serializers.DecimalField(max_digits=2, decimal_places=1, localize=True)
        assert field.to_representation(Decimal("1.1")) == "1,1"

    def test_localize_forces_coerce_to_string(self):
        field = serializers.DecimalField(
            max_digits=2, decimal_places=1, coerce_to_string=False, localize=True
        )
        assert isinstance(field.to_representation(Decimal("1.1")), str)


class TestQuantizedValueForDecimal(TestCase):
    def test_int_quantized_value_for_decimal(self):
        field = serializers.DecimalField(max_digits=4, decimal_places=2)
        value = field.to_internal_value(12).as_tuple()
        expected_digit_tuple = (0, (1, 2, 0, 0), -2)
        assert value == expected_digit_tuple

    def test_string_quantized_value_for_decimal(self):
        field = serializers.DecimalField(max_digits=4, decimal_places=2)
        value = field.to_internal_value("12").as_tuple()
        expected_digit_tuple = (0, (1, 2, 0, 0), -2)
        assert value == expected_digit_tuple

    def test_part_precision_string_quantized_value_for_decimal(self):
        field = serializers.DecimalField(max_digits=4, decimal_places=2)
        value = field.to_internal_value("12.0").as_tuple()
        expected_digit_tuple = (0, (1, 2, 0, 0), -2)
        assert value == expected_digit_tuple


class TestNormalizedOutputValueDecimalField(TestCase):
    """
    Test that we get the expected behavior of on DecimalField when normalize=True
    """

    def test_normalize_output(self):
        field = serializers.DecimalField(
            max_digits=4, decimal_places=3, normalize_output=True
        )
        output = field.to_representation(Decimal("1.000"))
        assert output == "1"

    def test_non_normalize_output(self):
        field = serializers.DecimalField(
            max_digits=4, decimal_places=3, normalize_output=False
        )
        output = field.to_representation(Decimal("1.000"))
        assert output == "1.000"

    def test_normalize_coeherce_to_string(self):
        field = serializers.DecimalField(
            max_digits=4,
            decimal_places=3,
            normalize_output=True,
            coerce_to_string=False,
        )
        output = field.to_representation(Decimal("1.000"))
        assert output == Decimal("1")


class TestNoDecimalPlaces(FieldValues):
    valid_inputs = {
        "0.12345": Decimal("0.12345"),
    }
    invalid_inputs = {
        "0.1234567": ["Ensure that there are no more than 6 digits in total."]
    }
    outputs = {
        "1.2345": "1.2345",
        "0": "0",
        "1.1": "1.1",
    }
    field = serializers.DecimalField(max_digits=6, decimal_places=None)


class TestRoundingDecimalField(TestCase):
    def test_valid_rounding(self):
        field = serializers.DecimalField(
            max_digits=4, decimal_places=2, rounding=ROUND_UP
        )
        assert field.to_representation(Decimal("1.234")) == "1.24"

        field = serializers.DecimalField(
            max_digits=4, decimal_places=2, rounding=ROUND_DOWN
        )
        assert field.to_representation(Decimal("1.234")) == "1.23"

    def test_invalid_rounding(self):
        with pytest.raises(AssertionError) as excinfo:
            serializers.DecimalField(
                max_digits=1, decimal_places=1, rounding="ROUND_UNKNOWN"
            )
        assert "Invalid rounding option" in str(excinfo.value)


# Date & time serializers...
class TestDateField(FieldValues):
    """
    Valid and invalid values for `DateField`.
    """

    valid_inputs = {
        "2001-01-01": datetime.date(2001, 1, 1),
        datetime.date(2001, 1, 1): datetime.date(2001, 1, 1),
    }
    invalid_inputs = {
        "abc": ["Date has wrong format. Use one of these formats instead: YYYY-MM-DD."],
        "2001-99-99": [
            "Date has wrong format. Use one of these formats instead: YYYY-MM-DD."
        ],
        "2001-01": [
            "Date has wrong format. Use one of these formats instead: YYYY-MM-DD."
        ],
        "2001": [
            "Date has wrong format. Use one of these formats instead: YYYY-MM-DD."
        ],
        datetime.datetime(2001, 1, 1, 12, 00): ["Expected a date but got a datetime."],
    }
    outputs = {
        datetime.date(2001, 1, 1): "2001-01-01",
        "2001-01-01": "2001-01-01",
        "2016-01-10": "2016-01-10",
        None: None,
        "": None,
    }
    field = serializers.DateField()


class TestCustomInputFormatDateField(FieldValues):
    """
    Valid and invalid values for `DateField` with a custom input format.
    """

    valid_inputs = {
        "1 Jan 2001": datetime.date(2001, 1, 1),
    }
    invalid_inputs = {
        "2001-01-01": [
            "Date has wrong format. Use one of these formats instead: DD [Jan-Dec] YYYY."
        ]
    }
    outputs = {}
    field = serializers.DateField(input_formats=["%d %b %Y"])


class TestCustomOutputFormatDateField(FieldValues):
    """
    Values for `DateField` with a custom output format.
    """

    valid_inputs = {}
    invalid_inputs = {}
    outputs = {datetime.date(2001, 1, 1): "01 Jan 2001"}
    field = serializers.DateField(format="%d %b %Y")


class TestNoOutputFormatDateField(FieldValues):
    """
    Values for `DateField` with no output format.
    """

    valid_inputs = {}
    invalid_inputs = {}
    outputs = {datetime.date(2001, 1, 1): datetime.date(2001, 1, 1)}
    field = serializers.DateField(format=None)


class TestDateTimeField(FieldValues):
    """
    Valid and invalid values for `DateTimeField`.
    """

    valid_inputs = {
        "2001-01-01 13:00": datetime.datetime(2001, 1, 1, 13, 00, tzinfo=utc),
        "2001-01-01T13:00": datetime.datetime(2001, 1, 1, 13, 00, tzinfo=utc),
        "2001-01-01T13:00Z": datetime.datetime(2001, 1, 1, 13, 00, tzinfo=utc),
        datetime.datetime(2001, 1, 1, 13, 00): datetime.datetime(
            2001, 1, 1, 13, 00, tzinfo=utc
        ),
        datetime.datetime(2001, 1, 1, 13, 00, tzinfo=utc): datetime.datetime(
            2001, 1, 1, 13, 00, tzinfo=utc
        ),
    }
    invalid_inputs = {
        "abc": [
            "Datetime has wrong format. Use one of these formats instead: YYYY-MM-DDThh:mm[:ss[.uuuuuu]][+HH:MM|-HH:MM|Z]."
        ],
        "2001-99-99T99:00": [
            "Datetime has wrong format. Use one of these formats instead: YYYY-MM-DDThh:mm[:ss[.uuuuuu]][+HH:MM|-HH:MM|Z]."
        ],
        "2018-08-16 22:00-24:00": [
            "Datetime has wrong format. Use one of these formats instead: YYYY-MM-DDThh:mm[:ss[.uuuuuu]][+HH:MM|-HH:MM|Z]."
        ],
        datetime.date(2001, 1, 1): ["Expected a datetime but got a date."],
        "9999-12-31T21:59:59.99990-03:00": ["Datetime value out of range."],
    }
    outputs = {
        datetime.datetime(2001, 1, 1, 13, 00): "2001-01-01T13:00:00Z",
        datetime.datetime(2001, 1, 1, 13, 00, tzinfo=utc): "2001-01-01T13:00:00Z",
        "2001-01-01T00:00:00": "2001-01-01T00:00:00",
        "2016-01-10T00:00:00": "2016-01-10T00:00:00",
        None: None,
        "": None,
    }
    field = serializers.DateTimeField(default_timezone=utc)


class TestCustomInputFormatDateTimeField(FieldValues):
    """
    Valid and invalid values for `DateTimeField` with a custom input format.
    """

    valid_inputs = {
        "1:35pm, 1 Jan 2001": datetime.datetime(2001, 1, 1, 13, 35, tzinfo=utc),
    }
    invalid_inputs = {
        "2001-01-01T20:50": [
            "Datetime has wrong format. Use one of these formats instead: hh:mm[AM|PM], DD [Jan-Dec] YYYY."
        ]
    }
    outputs = {}
    field = serializers.DateTimeField(
        default_timezone=utc, input_formats=["%I:%M%p, %d %b %Y"]
    )


class TestCustomOutputFormatDateTimeField(FieldValues):
    """
    Values for `DateTimeField` with a custom output format.
    """

    valid_inputs = {}
    invalid_inputs = {}
    outputs = {
        datetime.datetime(2001, 1, 1, 13, 00): "01:00PM, 01 Jan 2001",
    }
    field = serializers.DateTimeField(format="%I:%M%p, %d %b %Y")


class TestNoOutputFormatDateTimeField(FieldValues):
    """
    Values for `DateTimeField` with no output format.
    """

    valid_inputs = {}
    invalid_inputs = {}
    outputs = {
        datetime.datetime(2001, 1, 1, 13, 00): datetime.datetime(2001, 1, 1, 13, 00),
    }
    field = serializers.DateTimeField(format=None)


@override_settings(TIME_ZONE="UTC", USE_TZ=False)
class TestNaiveDateTimeField(FieldValues, TestCase):
    """
    Valid and invalid values for `DateTimeField` with naive datetimes.
    """

    valid_inputs = {
        datetime.datetime(2001, 1, 1, 13, 00, tzinfo=utc): datetime.datetime(
            2001, 1, 1, 13, 00
        ),
        "2001-01-01 13:00": datetime.datetime(2001, 1, 1, 13, 00),
    }
    invalid_inputs = {}
    outputs = {
        datetime.datetime(2001, 1, 1, 13, 00): "2001-01-01T13:00:00",
        datetime.datetime(2001, 1, 1, 13, 00, tzinfo=utc): "2001-01-01T13:00:00",
    }
    field = serializers.DateTimeField(default_timezone=None)


class TestTZWithDateTimeField(FieldValues):
    """
    Valid and invalid values for `DateTimeField` when not using UTC as the timezone.
    """

    @classmethod
    def setup_class(cls):
        # use class setup method, as class-level attribute will still be evaluated even if test is skipped
        kolkata = ZoneInfo("Asia/Kolkata")

        cls.valid_inputs = {
            "2016-12-19T10:00:00": datetime.datetime(2016, 12, 19, 10, tzinfo=kolkata),
            "2016-12-19T10:00:00+05:30": datetime.datetime(
                2016, 12, 19, 10, tzinfo=kolkata
            ),
            datetime.datetime(2016, 12, 19, 10): datetime.datetime(
                2016, 12, 19, 10, tzinfo=kolkata
            ),
        }
        cls.invalid_inputs = {}
        cls.outputs = {
            datetime.datetime(2016, 12, 19, 10): "2016-12-19T10:00:00+05:30",
            datetime.datetime(
                2016, 12, 19, 4, 30, tzinfo=utc
            ): "2016-12-19T10:00:00+05:30",
        }
        cls.field = serializers.DateTimeField(default_timezone=kolkata)


@override_settings(TIME_ZONE="UTC", USE_TZ=True)
class TestDefaultTZDateTimeField(TestCase):
    """
    Test the current/default timezone handling in `DateTimeField`.
    """

    @classmethod
    def setup_class(cls):
        cls.field = serializers.DateTimeField()
        cls.kolkata = ZoneInfo("Asia/Kolkata")

    def assertUTC(self, tzinfo):
        """
        Check UTC for datetime.timezone, ZoneInfo, and pytz tzinfo instances.
        """
        assert (
            tzinfo is utc
            or (getattr(tzinfo, "key", None) or getattr(tzinfo, "zone", None)) == "UTC"
        )

    def test_default_timezone(self):
        self.assertUTC(self.field.default_timezone())

    def test_current_timezone(self):
        self.assertUTC(self.field.default_timezone())
        activate(self.kolkata)
        assert self.field.default_timezone() == self.kolkata
        deactivate()
        self.assertUTC(self.field.default_timezone())


@override_settings(TIME_ZONE="UTC", USE_TZ=True)
class TestCustomTimezoneForDateTimeField(TestCase):

    @classmethod
    def setup_class(cls):
        cls.kolkata = ZoneInfo("Asia/Kolkata")
        cls.date_format = "%d/%m/%Y %H:%M"

    def test_should_render_date_time_in_default_timezone(self):
        field = serializers.DateTimeField(
            default_timezone=self.kolkata, format=self.date_format
        )
        dt = datetime.datetime(2018, 2, 8, 14, 15, 16, tzinfo=ZoneInfo("UTC"))

        with override(self.kolkata):
            rendered_date = field.to_representation(dt)

        rendered_date_in_timezone = dt.astimezone(self.kolkata).strftime(
            self.date_format
        )

        assert rendered_date == rendered_date_in_timezone


@pytest.mark.skipif(
    pytz is None,
    reason="Django 5.0 has removed pytz; this test should eventually be able to get removed.",
)
class TestPytzNaiveDayLightSavingTimeTimeZoneDateTimeField(FieldValues):
    """
    Invalid values for `DateTimeField` with datetime in DST shift (non-existing or ambiguous) and timezone with DST.
    Timezone America/New_York has DST shift from 2017-03-12T02:00:00 to 2017-03-12T03:00:00 and
     from 2017-11-05T02:00:00 to 2017-11-05T01:00:00 in 2017.
    """

    valid_inputs = {}
    invalid_inputs = {
        "2017-03-12T02:30:00": [
            'Invalid datetime for the timezone "America/New_York".'
        ],
        "2017-11-05T01:30:00": [
            'Invalid datetime for the timezone "America/New_York".'
        ],
    }
    outputs = {}

    if pytz:

        class MockTimezone(pytz.BaseTzInfo):
            @staticmethod
            def localize(value, is_dst):
                raise pytz.InvalidTimeError()

            def __str__(self):
                return "America/New_York"

        field = serializers.DateTimeField(default_timezone=MockTimezone())


@patch("rest_framework.utils.timezone.datetime_ambiguous", return_value=True)
class TestNaiveDayLightSavingTimeTimeZoneDateTimeField(FieldValues):
    """
    Invalid values for `DateTimeField` with datetime in DST shift (non-existing or ambiguous) and timezone with DST.
    Timezone America/New_York has DST shift from 2017-03-12T02:00:00 to 2017-03-12T03:00:00 and
     from 2017-11-05T02:00:00 to 2017-11-05T01:00:00 in 2017.
    """

    valid_inputs = {}
    invalid_inputs = {
        "2017-03-12T02:30:00": [
            'Invalid datetime for the timezone "America/New_York".'
        ],
        "2017-11-05T01:30:00": [
            'Invalid datetime for the timezone "America/New_York".'
        ],
    }
    outputs = {}

    class MockZoneInfoTimezone(datetime.tzinfo):
        def __str__(self):
            return "America/New_York"

    field = serializers.DateTimeField(default_timezone=MockZoneInfoTimezone())


class TestTimeField(FieldValues):
    """
    Valid and invalid values for `TimeField`.
    """

    valid_inputs = {
        "13:00": datetime.time(13, 00),
        datetime.time(13, 00): datetime.time(13, 00),
    }
    invalid_inputs = {
        "abc": [
            "Time has wrong format. Use one of these formats instead: hh:mm[:ss[.uuuuuu]]."
        ],
        "99:99": [
            "Time has wrong format. Use one of these formats instead: hh:mm[:ss[.uuuuuu]]."
        ],
    }
    outputs = {
        datetime.time(13, 0): "13:00:00",
        datetime.time(0, 0): "00:00:00",
        "00:00:00": "00:00:00",
        None: None,
        "": None,
    }
    field = serializers.TimeField()


class TestCustomInputFormatTimeField(FieldValues):
    """
    Valid and invalid values for `TimeField` with a custom input format.
    """

    valid_inputs = {
        "1:00pm": datetime.time(13, 00),
    }
    invalid_inputs = {
        "13:00": [
            "Time has wrong format. Use one of these formats instead: hh:mm[AM|PM]."
        ],
    }
    outputs = {}
    field = serializers.TimeField(input_formats=["%I:%M%p"])


class TestCustomOutputFormatTimeField(FieldValues):
    """
    Values for `TimeField` with a custom output format.
    """

    valid_inputs = {}
    invalid_inputs = {}
    outputs = {datetime.time(13, 00): "01:00PM"}
    field = serializers.TimeField(format="%I:%M%p")


class TestNoOutputFormatTimeField(FieldValues):
    """
    Values for `TimeField` with a no output format.
    """

    valid_inputs = {}
    invalid_inputs = {}
    outputs = {datetime.time(13, 00): datetime.time(13, 00)}
    field = serializers.TimeField(format=None)


class TestMinMaxDurationField(FieldValues):
    """
    Valid and invalid values for `DurationField` with min and max limits.
    """

    valid_inputs = {
        "3 08:32:01.000123": datetime.timedelta(
            days=3, hours=8, minutes=32, seconds=1, microseconds=123
        ),
        86401: datetime.timedelta(days=1, seconds=1),
    }
    invalid_inputs = {
        3600: ["Ensure this value is greater than or equal to 1 day, 0:00:00."],
        "4 08:32:01.000123": [
            "Ensure this value is less than or equal to 4 days, 0:00:00."
        ],
        "3600": ["Ensure this value is greater than or equal to 1 day, 0:00:00."],
    }
    outputs = {}
    field = serializers.DurationField(
        min_value=datetime.timedelta(days=1), max_value=datetime.timedelta(days=4)
    )


class TestDurationField(FieldValues):
    """
    Valid and invalid values for `DurationField`.
    """

    valid_inputs = {
        "13": datetime.timedelta(seconds=13),
        "3 08:32:01.000123": datetime.timedelta(
            days=3, hours=8, minutes=32, seconds=1, microseconds=123
        ),
        "08:01": datetime.timedelta(minutes=8, seconds=1),
        datetime.timedelta(
            days=3, hours=8, minutes=32, seconds=1, microseconds=123
        ): datetime.timedelta(days=3, hours=8, minutes=32, seconds=1, microseconds=123),
        3600: datetime.timedelta(hours=1),
        "-999999999 00": datetime.timedelta(days=-999999999),
        "999999999 00": datetime.timedelta(days=999999999),
    }
    invalid_inputs = {
        "abc": [
            "Duration has wrong format. Use one of these formats instead: [DD] [HH:[MM:]]ss[.uuuuuu]."
        ],
        "3 08:32 01.123": [
            "Duration has wrong format. Use one of these formats instead: [DD] [HH:[MM:]]ss[.uuuuuu]."
        ],
        "-1000000000 00": [
            "The number of days must be between -999999999 and 999999999."
        ],
        "1000000000 00": [
            "The number of days must be between -999999999 and 999999999."
        ],
    }
    outputs = {
        datetime.timedelta(
            days=3, hours=8, minutes=32, seconds=1, microseconds=123
        ): "3 08:32:01.000123",
    }
    field = serializers.DurationField()


# Choice types...


class TestChoiceField(FieldValues):
    """
    Valid and invalid values for `ChoiceField`.
    """

    valid_inputs = {
        "poor": "poor",
        "medium": "medium",
        "good": "good",
    }
    invalid_inputs = {"amazing": ['"amazing" is not a valid choice.']}
    outputs = {
        "good": "good",
        "": "",
        "amazing": "amazing",
    }
    field = serializers.ChoiceField(
        choices=[
            ("poor", "Poor quality"),
            ("medium", "Medium quality"),
            ("good", "Good quality"),
        ]
    )

    def test_allow_blank(self):
        """
        If `allow_blank=True` then '' is a valid input.
        """
        field = serializers.ChoiceField(
            allow_blank=True,
            choices=[
                ("poor", "Poor quality"),
                ("medium", "Medium quality"),
                ("good", "Good quality"),
            ],
        )
        output = field.run_validation("")
        assert output == ""

    def test_allow_null(self):
        """
        If `allow_null=True` then '' on HTML forms is treated as None.
        """
        field = serializers.ChoiceField(allow_null=True, choices=[1, 2, 3])
        field.field_name = "example"
        value = field.get_value(QueryDict("example="))
        assert value is None
        output = field.run_validation(None)
        assert output is None

    def test_iter_options(self):
        """
        iter_options() should return a list of options and option groups.
        """
        field = serializers.ChoiceField(
            choices=[
                ("Numbers", ["integer", "float"]),
                ("Strings", ["text", "email", "url"]),
                "boolean",
            ]
        )
        items = list(field.iter_options())

        assert items[0].start_option_group
        assert items[0].label == "Numbers"
        assert items[1].value == "integer"
        assert items[2].value == "float"
        assert items[3].end_option_group

        assert items[4].start_option_group
        assert items[4].label == "Strings"
        assert items[5].value == "text"
        assert items[6].value == "email"
        assert items[7].value == "url"
        assert items[8].end_option_group

        assert items[9].value == "boolean"

    def test_edit_choices(self):
        field = serializers.ChoiceField(
            allow_null=True,
            choices=[
                1,
                2,
            ],
        )
        field.choices = [1]
        assert field.run_validation(1) == 1
        with pytest.raises(serializers.ValidationError) as exc_info:
            field.run_validation(2)
        assert exc_info.value.detail == ['"2" is not a valid choice.']

    def test_enum_integer_choices(self):
        from enum import IntEnum

        class ChoiceCase(IntEnum):
            first = auto()
            second = auto()

        # Enum validate
        choices = [(ChoiceCase.first, "1"), (ChoiceCase.second, "2")]
        field = serializers.ChoiceField(choices=choices)
        assert field.run_validation(1) == 1
        assert field.run_validation(ChoiceCase.first) == 1
        assert field.run_validation("1") == 1
        # Enum.value validate
        choices = [(ChoiceCase.first.value, "1"), (ChoiceCase.second.value, "2")]
        field = serializers.ChoiceField(choices=choices)
        assert field.run_validation(1) == 1
        assert field.run_validation(ChoiceCase.first) == 1
        assert field.run_validation("1") == 1

    def test_integer_choices(self):
        class ChoiceCase(IntegerChoices):
            first = auto()
            second = auto()

        # Enum validate
        choices = [(ChoiceCase.first, "1"), (ChoiceCase.second, "2")]

        field = serializers.ChoiceField(choices=choices)
        assert field.run_validation(1) == 1
        assert field.run_validation(ChoiceCase.first) == 1
        assert field.run_validation("1") == 1

        choices = [(ChoiceCase.first.value, "1"), (ChoiceCase.second.value, "2")]

        field = serializers.ChoiceField(choices=choices)
        assert field.run_validation(1) == 1
        assert field.run_validation(ChoiceCase.first) == 1
        assert field.run_validation("1") == 1

    def test_text_choices(self):
        class ChoiceCase(TextChoices):
            first = auto()
            second = auto()

        # Enum validate
        choices = [(ChoiceCase.first, "first"), (ChoiceCase.second, "second")]

        field = serializers.ChoiceField(choices=choices)
        assert field.run_validation(ChoiceCase.first) == "first"
        assert field.run_validation("first") == "first"

        choices = [
            (ChoiceCase.first.value, "first"),
            (ChoiceCase.second.value, "second"),
        ]

        field = serializers.ChoiceField(choices=choices)
        assert field.run_validation(ChoiceCase.first) == "first"
        assert field.run_validation("first") == "first"


class TestChoiceFieldWithType(FieldValues):
    """
    Valid and invalid values for a `Choice` field that uses an integer type,
    instead of a char type.
    """

    valid_inputs = {
        "1": 1,
        3: 3,
    }
    invalid_inputs = {
        5: ['"5" is not a valid choice.'],
        "abc": ['"abc" is not a valid choice.'],
    }
    outputs = {"1": 1, 1: 1}
    field = serializers.ChoiceField(
        choices=[
            (1, "Poor quality"),
            (2, "Medium quality"),
            (3, "Good quality"),
        ]
    )


class TestChoiceFieldWithListChoices(FieldValues):
    """
    Valid and invalid values for a `Choice` field that uses a flat list for the
    choices, rather than a list of pairs of (`value`, `description`).
    """

    valid_inputs = {
        "poor": "poor",
        "medium": "medium",
        "good": "good",
    }
    invalid_inputs = {"awful": ['"awful" is not a valid choice.']}
    outputs = {"good": "good"}
    field = serializers.ChoiceField(choices=("poor", "medium", "good"))


class TestChoiceFieldWithGroupedChoices(FieldValues):
    """
    Valid and invalid values for a `Choice` field that uses a grouped list for the
    choices, rather than a list of pairs of (`value`, `description`).
    """

    valid_inputs = {
        "poor": "poor",
        "medium": "medium",
        "good": "good",
    }
    invalid_inputs = {"awful": ['"awful" is not a valid choice.']}
    outputs = {"good": "good"}
    field = serializers.ChoiceField(
        choices=[
            (
                "Category",
                (
                    ("poor", "Poor quality"),
                    ("medium", "Medium quality"),
                ),
            ),
            ("good", "Good quality"),
        ]
    )


class TestChoiceFieldWithMixedChoices(FieldValues):
    """
    Valid and invalid values for a `Choice` field that uses a single paired or
    grouped.
    """

    valid_inputs = {
        "poor": "poor",
        "medium": "medium",
        "good": "good",
    }
    invalid_inputs = {"awful": ['"awful" is not a valid choice.']}
    outputs = {"good": "good"}
    field = serializers.ChoiceField(
        choices=[
            (
                "Category",
                (("poor", "Poor quality"),),
            ),
            "medium",
            ("good", "Good quality"),
        ]
    )


class TestMultipleChoiceField(FieldValues):
    """
    Valid and invalid values for `MultipleChoiceField`.
    """

    valid_inputs = {
        (): list(),
        ("aircon",): ["aircon"],
        ("aircon", "manual"): ["aircon", "manual"],
        ("manual", "aircon"): ["manual", "aircon"],
    }
    invalid_inputs = {
        "abc": ['Expected a list of items but got type "str".'],
        ("aircon", "incorrect"): ['"incorrect" is not a valid choice.'],
    }
    outputs = [
        (["aircon", "manual", "incorrect"], ["aircon", "manual", "incorrect"]),
        (["manual", "aircon", "incorrect"], ["manual", "aircon", "incorrect"]),
    ]
    field = serializers.MultipleChoiceField(
        choices=[
            ("aircon", "AirCon"),
            ("manual", "Manual drive"),
            ("diesel", "Diesel"),
        ]
    )

    def test_against_partial_and_full_updates(self):
        field = serializers.MultipleChoiceField(choices=(("a", "a"), ("b", "b")))
        field.partial = False
        assert field.get_value(QueryDict("")) == []
        field.partial = True
        assert field.get_value(QueryDict('')) == rest_framework.fields.empty


class TestEmptyMultipleChoiceField(FieldValues):
    """
    Invalid values for `MultipleChoiceField(allow_empty=False)`.
    """

    valid_inputs = {}
    invalid_inputs = (([], ["This selection may not be empty."]),)
    outputs = []
    field = serializers.MultipleChoiceField(
        choices=[
            ("consistency", "Consistency"),
            ("availability", "Availability"),
            ("partition", "Partition tolerance"),
        ],
        allow_empty=False,
    )


# File serializers...


class MockFile:
    def __init__(self, name="", size=0, url=""):
        self.name = name
        self.size = size
        self.url = url

    def __eq__(self, other):
        return (
            isinstance(other, MockFile)
            and self.name == other.name
            and self.size == other.size
            and self.url == other.url
        )


class TestFileField(FieldValues):
    """
    Values for `FileField`.
    """

    valid_inputs = [
        (MockFile(name="example", size=10), MockFile(name="example", size=10))
    ]
    invalid_inputs = [
        (
            "invalid",
            ["The submitted data was not a file. Check the encoding type on the form."],
        ),
        (MockFile(name="example.txt", size=0), ["The submitted file is empty."]),
        (MockFile(name="", size=10), ["No filename could be determined."]),
        (
            MockFile(name="x" * 100, size=10),
            ["Ensure this filename has at most 10 characters (it has 100)."],
        ),
    ]
    outputs = [
        (MockFile(name="example.txt", url="/example.txt"), "/example.txt"),
        ("", None),
    ]
    field = serializers.FileField(max_length=10)


class TestFieldFieldWithName(FieldValues):
    """
    Values for `FileField` with a filename output instead of URLs.
    """

    valid_inputs = {}
    invalid_inputs = {}
    outputs = [(MockFile(name="example.txt", url="/example.txt"), "example.txt")]
    field = serializers.FileField(use_url=False)


def ext_validator(value):
    if not value.name.endswith(".png"):
        raise serializers.ValidationError(
            "File extension is not allowed. Allowed extensions is png."
        )


# Stub out mock Django `forms.ImageField` class so we don't *actually*
# call into it's regular validation, or require PIL for testing.
class PassImageValidation(DjangoImageField):
    default_validators = [ext_validator]

    def to_python(self, value):
        return value


class FailImageValidation(PassImageValidation):
    def to_python(self, value):
        if value.name == "badimage.png":
            raise serializers.ValidationError(self.error_messages["invalid_image"])
        return value


class TestInvalidImageField(FieldValues):
    """
    Values for an invalid `ImageField`.
    """

    valid_inputs = {}
    invalid_inputs = [
        (
            MockFile(name="badimage.png", size=10),
            [
                "Upload a valid image. The file you uploaded was either not an image or a corrupted image."
            ],
        ),
        (
            MockFile(name="goodimage.html", size=10),
            ["File extension is not allowed. Allowed extensions is png."],
        ),
    ]
    outputs = {}
    field = serializers.ImageField(_DjangoImageField=FailImageValidation)


class TestValidImageField(FieldValues):
    """
    Values for an valid `ImageField`.
    """

    valid_inputs = [
        (MockFile(name="example.png", size=10), MockFile(name="example.png", size=10))
    ]
    invalid_inputs = {}
    outputs = {}
    field = serializers.ImageField(_DjangoImageField=PassImageValidation)


# Composite serializers...


class TestListField(FieldValues):
    """
    Values for `ListField` with IntegerField as child.
    """

    valid_inputs = [([1, 2, 3], [1, 2, 3]), (["1", "2", "3"], [1, 2, 3]), ([], [])]
    invalid_inputs = [
        ("not a list", ['Expected a list of items but got type "str".']),
        (
            [1, 2, "error", "error"],
            {2: ["A valid integer is required."], 3: ["A valid integer is required."]},
        ),
        ({"one": "two"}, ['Expected a list of items but got type "dict".']),
    ]
    outputs = [([1, 2, 3], [1, 2, 3]), (["1", "2", "3"], [1, 2, 3])]
    field = serializers.ListField(child=serializers.IntegerField())

    def test_no_source_on_child(self):
        with pytest.raises(AssertionError) as exc_info:
            serializers.ListField(child=serializers.IntegerField(source="other"))

        assert str(exc_info.value) == (
            "The `source` argument is not meaningful when applied to a `child=` field. "
            "Remove `source=` from the field declaration."
        )

    def test_collection_types_are_invalid_input(self):
        field = serializers.ListField(child=serializers.CharField())
        input_value = {"one": "two"}

        with pytest.raises(serializers.ValidationError) as exc_info:
            field.to_internal_value(input_value)
        assert exc_info.value.detail == [
            'Expected a list of items but got type "dict".'
        ]

    def test_constructor_misuse_raises(self):
        # Test that `ListField` can only be instantiated with keyword arguments
        with pytest.raises(TypeError):
            serializers.ListField(serializers.CharField())


class TestNestedListField(FieldValues):
    """
    Values for nested `ListField` with IntegerField as child.
    """

    valid_inputs = [([[1, 2], [3]], [[1, 2], [3]]), ([[]], [[]])]
    invalid_inputs = [
        (["not a list"], {0: ['Expected a list of items but got type "str".']}),
        (
            [[1, 2, "error"], ["error"]],
            {
                0: {2: ["A valid integer is required."]},
                1: {0: ["A valid integer is required."]},
            },
        ),
        ([{"one": "two"}], {0: ['Expected a list of items but got type "dict".']}),
    ]
    outputs = [
        ([[1, 2], [3]], [[1, 2], [3]]),
    ]
    field = serializers.ListField(
        child=serializers.ListField(child=serializers.IntegerField())
    )


class TestListFieldWithDjangoValidationErrors(FieldValues, TestCase):
    """
    Values for `ListField` with UUIDField as child
    (since UUIDField can throw ValidationErrors from Django).
    The idea is to test that Django's ValidationErrors raised
    from Django internals are caught and serializers in a way
    that is structurally consistent with DRF's ValidationErrors.
    """

    valid_inputs = []
    invalid_inputs = [
        (
            [
                "not-a-valid-uuid",
                "d7364368-d1b3-4455-aaa3-56439b460ca2",
                "some-other-invalid-uuid",
            ],
            {
                0: [
                    exceptions.ErrorDetail(
                        string="“not-a-valid-uuid” is not a valid UUID.", code="invalid"
                    )
                ],
                1: [
                    exceptions.ErrorDetail(
                        string='Invalid pk "d7364368-d1b3-4455-aaa3-56439b460ca2" - object does not exist.',
                        code="does_not_exist",
                    )
                ],
                2: [
                    exceptions.ErrorDetail(
                        string="“some-other-invalid-uuid” is not a valid UUID.",
                        code="invalid",
                    )
                ],
            },
        ),
    ]
    outputs = {}
    field = serializers.ListField(
        child=serializers.PrimaryKeyRelatedField(
            queryset=UUIDForeignKeyTarget.objects.all()
        )
    )


class TestEmptyListField(FieldValues):
    """
    Values for `ListField` with allow_empty=False flag.
    """

    valid_inputs = {}
    invalid_inputs = [([], ["This list may not be empty."])]
    outputs = {}
    field = serializers.ListField(child=serializers.IntegerField(), allow_empty=False)


class TestListFieldLengthLimit(FieldValues):
    valid_inputs = ()
    invalid_inputs = [
        ((0, 1), ["Ensure this field has at least 3 elements."]),
        ((0, 1, 2, 3, 4, 5), ["Ensure this field has no more than 4 elements."]),
    ]
    outputs = ()
    field = serializers.ListField(
        child=serializers.IntegerField(), min_length=3, max_length=4
    )


class TestUnvalidatedListField(FieldValues):
    """
    Values for `ListField` with no `child` argument.
    """

    valid_inputs = [
        ([1, "2", True, [4, 5, 6]], [1, "2", True, [4, 5, 6]]),
    ]
    invalid_inputs = [
        ("not a list", ['Expected a list of items but got type "str".']),
    ]
    outputs = [
        ([1, "2", True, [4, 5, 6]], [1, "2", True, [4, 5, 6]]),
    ]
    field = serializers.ListField()


class TestDictField(FieldValues):
    """
    Values for `DictField` with CharField as child.
    """

    valid_inputs = [
        ({"a": 1, "b": "2", 3: 3}, {"a": "1", "b": "2", "3": "3"}),
        ({}, {}),
    ]
    invalid_inputs = [
        (
            {"a": 1, "b": None, "c": None},
            {
                "b": ["This field may not be null."],
                "c": ["This field may not be null."],
            },
        ),
        ("not a dict", ['Expected a dictionary of items but got type "str".']),
    ]
    outputs = [
        ({"a": 1, "b": "2", 3: 3}, {"a": "1", "b": "2", "3": "3"}),
    ]
    field = serializers.DictField(child=serializers.CharField())

    def test_no_source_on_child(self):
        with pytest.raises(AssertionError) as exc_info:
            serializers.DictField(child=serializers.CharField(source="other"))

        assert str(exc_info.value) == (
            "The `source` argument is not meaningful when applied to a `child=` field. "
            "Remove `source=` from the field declaration."
        )

    def test_allow_null(self):
        """
        If `allow_null=True` then `None` is a valid input.
        """
        field = serializers.DictField(allow_null=True)
        output = field.run_validation(None)
        assert output is None

    def test_allow_empty_disallowed(self):
        """
        If allow_empty is False then an empty dict is not a valid input.
        """
        field = serializers.DictField(allow_empty=False)
        with pytest.raises(serializers.ValidationError) as exc_info:
            field.run_validation({})

        assert exc_info.value.detail == ["This dictionary may not be empty."]


class TestNestedDictField(FieldValues):
    """
    Values for nested `DictField` with CharField as child.
    """

    valid_inputs = [
        (
            {0: {"a": 1, "b": "2"}, 1: {3: 3}},
            {"0": {"a": "1", "b": "2"}, "1": {"3": "3"}},
        ),
    ]
    invalid_inputs = [
        (
            {0: {"a": 1, "b": None}, 1: {"c": None}},
            {
                "0": {"b": ["This field may not be null."]},
                "1": {"c": ["This field may not be null."]},
            },
        ),
        (
            {0: "not a dict"},
            {"0": ['Expected a dictionary of items but got type "str".']},
        ),
    ]
    outputs = [
        (
            {0: {"a": 1, "b": "2"}, 1: {3: 3}},
            {"0": {"a": "1", "b": "2"}, "1": {"3": "3"}},
        ),
    ]
    field = serializers.DictField(
        child=serializers.DictField(child=serializers.CharField())
    )


class TestDictFieldWithNullChild(FieldValues):
    """
    Values for `DictField` with allow_null CharField as child.
    """

    valid_inputs = [
        ({"a": None, "b": "2", 3: 3}, {"a": None, "b": "2", "3": "3"}),
    ]
    invalid_inputs = []
    outputs = [
        ({"a": None, "b": "2", 3: 3}, {"a": None, "b": "2", "3": "3"}),
    ]
    field = serializers.DictField(child=serializers.CharField(allow_null=True))


class TestUnvalidatedDictField(FieldValues):
    """
    Values for `DictField` with no `child` argument.
    """

    valid_inputs = [
        ({"a": 1, "b": [4, 5, 6], 1: 123}, {"a": 1, "b": [4, 5, 6], "1": 123}),
    ]
    invalid_inputs = [
        ("not a dict", ['Expected a dictionary of items but got type "str".']),
    ]
    outputs = [
        ({"a": 1, "b": [4, 5, 6]}, {"a": 1, "b": [4, 5, 6]}),
    ]
    field = serializers.DictField()


class TestHStoreField(FieldValues):
    """
    Values for `ListField` with CharField as child.
    """

    valid_inputs = [
        ({"a": 1, "b": "2", 3: 3}, {"a": "1", "b": "2", "3": "3"}),
        ({"a": 1, "b": None}, {"a": "1", "b": None}),
    ]
    invalid_inputs = [
        ("not a dict", ['Expected a dictionary of items but got type "str".']),
    ]
    outputs = [
        ({"a": 1, "b": "2", 3: 3}, {"a": "1", "b": "2", "3": "3"}),
    ]
    field = serializers.HStoreField()

    def test_child_is_charfield(self):
        with pytest.raises(AssertionError) as exc_info:
            serializers.HStoreField(child=serializers.IntegerField())

        assert str(exc_info.value) == (
            "The `child` argument must be an instance of `CharField`, "
            "as the hstore extension stores values as strings."
        )

    def test_no_source_on_child(self):
        with pytest.raises(AssertionError) as exc_info:
            serializers.HStoreField(child=serializers.CharField(source="other"))

        assert str(exc_info.value) == (
            "The `source` argument is not meaningful when applied to a `child=` field. "
            "Remove `source=` from the field declaration."
        )

    def test_allow_null(self):
        """
        If `allow_null=True` then `None` is a valid input.
        """
        field = serializers.HStoreField(allow_null=True)
        output = field.run_validation(None)
        assert output is None


class TestJSONField(FieldValues):
    """
    Values for `JSONField`.
    """

    valid_inputs = [
        (
            {"a": 1, "b": ["some", "list", True, 1.23], "3": None},
            {"a": 1, "b": ["some", "list", True, 1.23], "3": None},
        ),
    ]
    invalid_inputs = [
        ({"a": set()}, ["Value must be valid JSON."]),
        ({"a": float("inf")}, ["Value must be valid JSON."]),
    ]
    outputs = [
        (
            {"a": 1, "b": ["some", "list", True, 1.23], "3": 3},
            {"a": 1, "b": ["some", "list", True, 1.23], "3": 3},
        ),
    ]
    field = serializers.JSONField()

    def test_html_input_as_json_string(self):
        """
        HTML inputs should be treated as a serialized JSON string.
        """

        class TestSerializer(serializers.Serializer):
            config = serializers.JSONField()

        data = QueryDict(mutable=True)
        data.update({"config": '{"a":1}'})
        serializer = TestSerializer(data=data)
        assert serializer.is_valid()
        assert serializer.validated_data == {"config": {"a": 1}}


class TestBinaryJSONField(FieldValues):
    """
    Values for `JSONField` with binary=True.
    """

    valid_inputs = [
        (
            b'{"a": 1, "3": null, "b": ["some", "list", true, 1.23]}',
            {"a": 1, "b": ["some", "list", True, 1.23], "3": None},
        ),
    ]
    invalid_inputs = [
        ('{"a": "unterminated string}', ["Value must be valid JSON."]),
    ]
    outputs = [
        (["some", "list", True, 1.23], b'["some", "list", true, 1.23]'),
    ]
    field = serializers.JSONField(binary=True)


# Tests for FileField.
# --------------------


class MockRequest:
    def build_absolute_uri(self, value):
        return "http://example.com" + value


class TestFileFieldContext:
    def test_fully_qualified_when_request_in_context(self):
        field = serializers.FileField(max_length=10)
        field._context = {"request": MockRequest()}
        obj = MockFile(name="example.txt", url="/example.txt")
        value = field.to_representation(obj)
        assert value == "http://example.com/example.txt"


# Tests for FilePathField.
# --------------------


class TestFilePathFieldRequired:
    def test_required_passed_to_both_django_file_path_field_and_base(self):
        field = serializers.FilePathField(
            path=os.path.abspath(os.path.dirname(__file__)),
            required=False,
        )
        assert "" in field.choices  # Django adds empty choice if not required
        assert field.required is False
        with pytest.raises(SkipField):
            field.run_validation(empty)


# Tests for SerializerMethodField.
# --------------------------------


class TestSerializerMethodField:
    def test_serializer_method_field(self):
        class ExampleSerializer(serializers.Serializer):
            example_field = serializers.SerializerMethodField()

            def get_example_field(self, obj):
                return "ran get_example_field(%d)" % obj["example_field"]

        serializer = ExampleSerializer({"example_field": 123})
        assert serializer.data == {"example_field": "ran get_example_field(123)"}

    def test_redundant_method_name(self):
        # Prior to v3.10, redundant method names were not allowed.
        # This restriction has since been removed.
        class ExampleSerializer(serializers.Serializer):
            example_field = serializers.SerializerMethodField("get_example_field")

        field = ExampleSerializer().fields["example_field"]
        assert field.method_name == "get_example_field"


# Tests for ModelField.
# ---------------------


class TestModelField:
    def test_max_length_init(self):
        field = serializers.ModelField(None)
        assert len(field.validators) == 0

        field = serializers.ModelField(None, max_length=10)
        assert len(field.validators) == 1


# Tests for validation errors
# ---------------------------


class TestValidationErrorCode:
    @pytest.mark.parametrize("use_list", (False, True))
    def test_validationerror_code_with_msg(self, use_list):

        class ExampleSerializer(serializers.Serializer):
            password = serializers.CharField()

            def validate_password(self, obj):
                err = DjangoValidationError(
                    "exc_msg %s",
                    code="exc_code",
                    params=("exc_param",),
                )
                if use_list:
                    err = DjangoValidationError([err])
                raise err

        serializer = ExampleSerializer(data={"password": 123})
        serializer.is_valid()
        assert serializer.errors == {"password": ["exc_msg exc_param"]}
        assert serializer.errors["password"][0].code == "exc_code"

    @pytest.mark.parametrize("use_list", (False, True))
    def test_validationerror_code_with_msg_including_percent(self, use_list):

        class ExampleSerializer(serializers.Serializer):
            password = serializers.CharField()

            def validate_password(self, obj):
                err = DjangoValidationError("exc_msg with %", code="exc_code")
                if use_list:
                    err = DjangoValidationError([err])
                raise err

        serializer = ExampleSerializer(data={"password": 123})
        serializer.is_valid()
        assert serializer.errors == {"password": ["exc_msg with %"]}
        assert serializer.errors["password"][0].code == "exc_code"

    @pytest.mark.parametrize(
        "code",
        (
            None,
            "exc_code",
        ),
    )
    @pytest.mark.parametrize("use_list", (False, True))
    def test_validationerror_code_with_dict(self, use_list, code):

        class ExampleSerializer(serializers.Serializer):

            def validate(self, obj):
                if code is None:
                    err = DjangoValidationError(
                        {
                            "email": "email error",
                        }
                    )
                else:
                    err = DjangoValidationError(
                        {
                            "email": DjangoValidationError("email error", code=code),
                        }
                    )
                if use_list:
                    err = DjangoValidationError([err])
                raise err

        serializer = ExampleSerializer(data={})
        serializer.is_valid()
        expected_code = code if code else "invalid"
        if use_list:
            assert serializer.errors == {
                "non_field_errors": [
                    exceptions.ErrorDetail(string="email error", code=expected_code)
                ]
            }
        else:
            assert serializer.errors == {
                "email": ["email error"],
            }
            assert serializer.errors["email"][0].code == expected_code

    @pytest.mark.parametrize(
        "code",
        (
            None,
            "exc_code",
        ),
    )
    def test_validationerror_code_with_dict_list_same_code(self, code):

        class ExampleSerializer(serializers.Serializer):

            def validate(self, obj):
                if code is None:
                    raise DjangoValidationError(
                        {"email": ["email error 1", "email error 2"]}
                    )
                raise DjangoValidationError(
                    {
                        "email": [
                            DjangoValidationError("email error 1", code=code),
                            DjangoValidationError("email error 2", code=code),
                        ]
                    }
                )

        serializer = ExampleSerializer(data={})
        serializer.is_valid()
        expected_code = code if code else "invalid"
        assert serializer.errors == {
            "email": [
                exceptions.ErrorDetail(string="email error 1", code=expected_code),
                exceptions.ErrorDetail(string="email error 2", code=expected_code),
            ]
        }