import copy
import datetime
import json
import uuid

from django.core.exceptions import NON_FIELD_ERRORS
from django.core.files.uploadedfile import SimpleUploadedFile
from django.core.validators import MaxValueValidator, RegexValidator
from django.forms import (
    BooleanField,
    BoundField,
    CharField,
    CheckboxSelectMultiple,
    ChoiceField,
    DateField,
    DateTimeField,
    EmailField,
    Field,
    FileField,
    FileInput,
    FloatField,
    Form,
    HiddenInput,
    ImageField,
    IntegerField,
    MultipleChoiceField,
    MultipleHiddenInput,
    MultiValueField,
    MultiWidget,
    NullBooleanField,
    PasswordInput,
    RadioSelect,
    Select,
    SplitDateTimeField,
    SplitHiddenDateTimeWidget,
    Textarea,
    TextInput,
    TimeField,
    ValidationError,
)
from django.forms.renderers import DjangoTemplates, get_default_renderer
from django.forms.utils import ErrorDict, ErrorList
from django.http import QueryDict
from django.template import Context, Template
from django.test import SimpleTestCase
from django.test.utils import override_settings
from django.utils.datastructures import MultiValueDict
from django.utils.safestring import mark_safe

from . import jinja2_tests


class FrameworkForm(Form):
    name = CharField()
    language = ChoiceField(choices=[("P", "Python"), ("J", "Java")], widget=RadioSelect)


class Person(Form):
    first_name = CharField()
    last_name = CharField()
    birthday = DateField()


class PersonNew(Form):
    first_name = CharField(widget=TextInput(attrs={"id": "first_name_id"}))
    last_name = CharField()
    birthday = DateField()


class SongForm(Form):
    name = CharField()
    composers = MultipleChoiceField(
        choices=[("J", "John Lennon"), ("P", "Paul McCartney")],
        widget=CheckboxSelectMultiple,
    )


class MultiValueDictLike(dict):
    def getlist(self, key):
        return [self[key]]


class FormsTestCase(SimpleTestCase):
    # A Form is a collection of Fields. It knows how to validate a set of data
    # and it knows how to render itself in a couple of default ways (e.g., an
    # HTML table). You can pass it data in __init__(), as a dictionary.

    def test_form(self):
        # Pass a dictionary to a Form's __init__().
        p = Person(
            {"first_name": "John", "last_name": "Lennon", "birthday": "1940-10-9"}
        )

        self.assertTrue(p.is_bound)
        self.assertEqual(p.errors, {})
        self.assertIsInstance(p.errors, dict)
        self.assertTrue(p.is_valid())
        self.assertHTMLEqual(p.errors.as_ul(), "")
        self.assertEqual(p.errors.as_text(), "")
        self.assertEqual(p.cleaned_data["first_name"], "John")
        self.assertEqual(p.cleaned_data["last_name"], "Lennon")
        self.assertEqual(p.cleaned_data["birthday"], datetime.date(1940, 10, 9))
        self.assertHTMLEqual(
            str(p["first_name"]),
            '<input type="text" name="first_name" value="John" id="id_first_name" '
            "required>",
        )
        self.assertHTMLEqual(
            str(p["last_name"]),
            '<input type="text" name="last_name" value="Lennon" id="id_last_name" '
            "required>",
        )
        self.assertHTMLEqual(
            str(p["birthday"]),
            '<input type="text" name="birthday" value="1940-10-9" id="id_birthday" '
            "required>",
        )

        msg = (
            "Key 'nonexistentfield' not found in 'Person'. Choices are: birthday, "
            "first_name, last_name."
        )
        with self.assertRaisesMessage(KeyError, msg):
            p["nonexistentfield"]

        form_output = []

        for boundfield in p:
            form_output.append(str(boundfield))

        self.assertHTMLEqual(
            "\n".join(form_output),
            '<input type="text" name="first_name" value="John" id="id_first_name" '
            "required>"
            '<input type="text" name="last_name" value="Lennon" id="id_last_name" '
            "required>"
            '<input type="text" name="birthday" value="1940-10-9" id="id_birthday" '
            "required>",
        )

        form_output = []

        for boundfield in p:
            form_output.append([boundfield.label, boundfield.data])

        self.assertEqual(
            form_output,
            [
                ["First name", "John"],
                ["Last name", "Lennon"],
                ["Birthday", "1940-10-9"],
            ],
        )
        self.assertHTMLEqual(
            str(p),
            '<div><label for="id_first_name">First name:</label><input type="text" '
            'name="first_name" value="John" required id="id_first_name"></div><div>'
            '<label for="id_last_name">Last name:</label><input type="text" '
            'name="last_name" value="Lennon" required id="id_last_name"></div><div>'
            '<label for="id_birthday">Birthday:</label><input type="text" '
            'name="birthday" value="1940-10-9" required id="id_birthday"></div>',
        )
        self.assertHTMLEqual(
            p.as_div(),
            '<div><label for="id_first_name">First name:</label><input type="text" '
            'name="first_name" value="John" required id="id_first_name"></div><div>'
            '<label for="id_last_name">Last name:</label><input type="text" '
            'name="last_name" value="Lennon" required id="id_last_name"></div><div>'
            '<label for="id_birthday">Birthday:</label><input type="text" '
            'name="birthday" value="1940-10-9" required id="id_birthday"></div>',
        )

    def test_empty_dict(self):
        # Empty dictionaries are valid, too.
        p = Person({})
        self.assertTrue(p.is_bound)
        self.assertEqual(p.errors["first_name"], ["This field is required."])
        self.assertEqual(p.errors["last_name"], ["This field is required."])
        self.assertEqual(p.errors["birthday"], ["This field is required."])
        self.assertFalse(p.is_valid())
        self.assertEqual(p.cleaned_data, {})
        self.assertHTMLEqual(
            str(p),
            '<div><label for="id_first_name">First name:</label>'
            '<ul class="errorlist" id="id_first_name_error"><li>This field is required.'
            '</li></ul><input type="text" name="first_name" aria-invalid="true" '
            'required id="id_first_name" aria-describedby="id_first_name_error"></div>'
            '<div><label for="id_last_name">Last name:</label>'
            '<ul class="errorlist" id="id_last_name_error"><li>This field is required.'
            '</li></ul><input type="text" name="last_name" aria-invalid="true" '
            'required id="id_last_name" aria-describedby="id_last_name_error"></div>'
            '<div><label for="id_birthday">Birthday:</label>'
            '<ul class="errorlist" id="id_birthday_error"><li>This field is required.'
            '</li></ul><input type="text" name="birthday" aria-invalid="true" required '
            'id="id_birthday" aria-describedby="id_birthday_error"></div>',
        )
        self.assertHTMLEqual(
            p.as_table(),
            """<tr><th><label for="id_first_name">First name:</label></th><td>
<ul class="errorlist" id="id_first_name_error"><li>This field is required.</li></ul>
<input type="text" name="first_name" id="id_first_name" aria-invalid="true" required
aria-describedby="id_first_name_error">
</td></tr><tr><th><label for="id_last_name">Last name:</label></th>
<td><ul class="errorlist" id="id_last_name_error"><li>This field is required.</li></ul>
<input type="text" name="last_name" id="id_last_name" aria-invalid="true" required
aria-describedby="id_last_name_error">
</td></tr><tr><th><label for="id_birthday">Birthday:</label></th>
<td><ul class="errorlist" id="id_birthday_error"><li>This field is required.</li></ul>
<input type="text" name="birthday" id="id_birthday" aria-invalid="true" required
aria-describedby="id_birthday_error">
</td></tr>""",
        )
        self.assertHTMLEqual(
            p.as_ul(),
            """<li><ul class="errorlist" id="id_first_name_error">
<li>This field is required.</li></ul>
<label for="id_first_name">First name:</label>
<input type="text" name="first_name" id="id_first_name" aria-invalid="true" required
aria-describedby="id_first_name_error">
</li><li><ul class="errorlist" id="id_last_name_error"><li>This field is required.</li>
</ul><label for="id_last_name">Last name:</label>
<input type="text" name="last_name" id="id_last_name" aria-invalid="true" required
aria-describedby="id_last_name_error">
</li><li><ul class="errorlist" id="id_birthday_error"><li>This field is required.</li>
</ul><label for="id_birthday">Birthday:</label>
<input type="text" name="birthday" id="id_birthday" aria-invalid="true" required
aria-describedby="id_birthday_error">
</li>""",
        )
        self.assertHTMLEqual(
            p.as_p(),
            """<ul class="errorlist" id="id_first_name_error"><li>
This field is required.</li></ul>
<p><label for="id_first_name">First name:</label>
<input type="text" name="first_name" id="id_first_name" aria-invalid="true" required
aria-describedby="id_first_name_error">
</p><ul class="errorlist" id="id_last_name_error"><li>This field is required.</li></ul>
<p><label for="id_last_name">Last name:</label>
<input type="text" name="last_name" id="id_last_name" aria-invalid="true" required
aria-describedby="id_last_name_error">
</p><ul class="errorlist" id="id_birthday_error"><li>This field is required.</li></ul>
<p><label for="id_birthday">Birthday:</label>
<input type="text" name="birthday" id="id_birthday" aria-invalid="true" required
aria-describedby="id_birthday_error">
</p>""",
        )
        self.assertHTMLEqual(
            p.as_div(),
            '<div><label for="id_first_name">First name:</label>'
            '<ul class="errorlist" id="id_first_name_error"><li>This field is required.'
            '</li></ul><input type="text" name="first_name" aria-invalid="true" '
            'required id="id_first_name" aria-describedby="id_first_name_error"></div>'
            '<div><label for="id_last_name">Last name:</label>'
            '<ul class="errorlist" id="id_last_name_error"><li>This field is required.'
            '</li></ul><input type="text" name="last_name" aria-invalid="true" '
            'required id="id_last_name" aria-describedby="id_last_name_error"></div>'
            '<div><label for="id_birthday">Birthday:</label>'
            '<ul class="errorlist" id="id_birthday_error"><li>This field is required.'
            '</li></ul><input type="text" name="birthday" aria-invalid="true" required '
            'id="id_birthday" aria-describedby="id_birthday_error"></div>',
        )

    def test_empty_querydict_args(self):
        data = QueryDict()
        files = QueryDict()
        p = Person(data, files)
        self.assertIs(p.data, data)
        self.assertIs(p.files, files)

    def test_unbound_form(self):
        # If you don't pass any values to the Form's __init__(), or if you pass
        # None, the Form will be considered unbound and won't do any
        # validation. Form.errors will be an empty dictionary *but*
        # Form.is_valid() will return False.
        p = Person()
        self.assertFalse(p.is_bound)
        self.assertEqual(p.errors, {})
        self.assertFalse(p.is_valid())
        with self.assertRaises(AttributeError):
            p.cleaned_data

        self.assertHTMLEqual(
            str(p),
            '<div><label for="id_first_name">First name:</label><input type="text" '
            'name="first_name" id="id_first_name" required></div><div><label '
            'for="id_last_name">Last name:</label><input type="text" name="last_name" '
            'id="id_last_name" required></div><div><label for="id_birthday">'
            'Birthday:</label><input type="text" name="birthday" id="id_birthday" '
            "required></div>",
        )
        self.assertHTMLEqual(
            p.as_table(),
            """<tr><th><label for="id_first_name">First name:</label></th><td>
<input type="text" name="first_name" id="id_first_name" required></td></tr>
<tr><th><label for="id_last_name">Last name:</label></th><td>
<input type="text" name="last_name" id="id_last_name" required></td></tr>
<tr><th><label for="id_birthday">Birthday:</label></th><td>
<input type="text" name="birthday" id="id_birthday" required></td></tr>""",
        )
        self.assertHTMLEqual(
            p.as_ul(),
            """<li><label for="id_first_name">First name:</label>
<input type="text" name="first_name" id="id_first_name" required></li>
<li><label for="id_last_name">Last name:</label>
<input type="text" name="last_name" id="id_last_name" required></li>
<li><label for="id_birthday">Birthday:</label>
<input type="text" name="birthday" id="id_birthday" required></li>""",
        )
        self.assertHTMLEqual(
            p.as_p(),
            """<p><label for="id_first_name">First name:</label>
<input type="text" name="first_name" id="id_first_name" required></p>
<p><label for="id_last_name">Last name:</label>
<input type="text" name="last_name" id="id_last_name" required></p>
<p><label for="id_birthday">Birthday:</label>
<input type="text" name="birthday" id="id_birthday" required></p>""",
        )
        self.assertHTMLEqual(
            p.as_div(),
            '<div><label for="id_first_name">First name:</label><input type="text" '
            'name="first_name" id="id_first_name" required></div><div><label '
            'for="id_last_name">Last name:</label><input type="text" name="last_name" '
            'id="id_last_name" required></div><div><label for="id_birthday">'
            'Birthday:</label><input type="text" name="birthday" id="id_birthday" '
            "required></div>",
        )

    def test_unicode_values(self):
        # Unicode values are handled properly.
        p = Person(
            {
                "first_name": "John",
                "last_name": "\u0160\u0110\u0106\u017d\u0107\u017e\u0161\u0111",
                "birthday": "1940-10-9",
            }
        )
        self.assertHTMLEqual(
            p.as_table(),
            '<tr><th><label for="id_first_name">First name:</label></th><td>'
            '<input type="text" name="first_name" value="John" id="id_first_name" '
            "required></td></tr>\n"
            '<tr><th><label for="id_last_name">Last name:</label>'
            '</th><td><input type="text" name="last_name" '
            'value="\u0160\u0110\u0106\u017d\u0107\u017e\u0161\u0111"'
            'id="id_last_name" required></td></tr>\n'
            '<tr><th><label for="id_birthday">Birthday:</label></th><td>'
            '<input type="text" name="birthday" value="1940-10-9" id="id_birthday" '
            "required></td></tr>",
        )
        self.assertHTMLEqual(
            p.as_ul(),
            '<li><label for="id_first_name">First name:</label> '
            '<input type="text" name="first_name" value="John" id="id_first_name" '
            "required></li>\n"
            '<li><label for="id_last_name">Last name:</label> '
            '<input type="text" name="last_name" '
            'value="\u0160\u0110\u0106\u017d\u0107\u017e\u0161\u0111" '
            'id="id_last_name" required></li>\n'
            '<li><label for="id_birthday">Birthday:</label> '
            '<input type="text" name="birthday" value="1940-10-9" id="id_birthday" '
            "required></li>",
        )
        self.assertHTMLEqual(
            p.as_p(),
            '<p><label for="id_first_name">First name:</label> '
            '<input type="text" name="first_name" value="John" id="id_first_name" '
            "required></p>\n"
            '<p><label for="id_last_name">Last name:</label> '
            '<input type="text" name="last_name" '
            'value="\u0160\u0110\u0106\u017d\u0107\u017e\u0161\u0111" '
            'id="id_last_name" required></p>\n'
            '<p><label for="id_birthday">Birthday:</label> '
            '<input type="text" name="birthday" value="1940-10-9" id="id_birthday" '
            "required></p>",
        )
        self.assertHTMLEqual(
            p.as_div(),
            '<div><label for="id_first_name">First name:</label>'
            '<input type="text" name="first_name" value="John" id="id_first_name" '
            'required></div><div><label for="id_last_name">Last name:</label>'
            '<input type="text" name="last_name"'
            'value="\u0160\u0110\u0106\u017d\u0107\u017e\u0161\u0111" '
            'id="id_last_name" required></div><div><label for="id_birthday">'
            'Birthday:</label><input type="text" name="birthday" value="1940-10-9" '
            'id="id_birthday" required></div>',
        )

        p = Person({"last_name": "Lennon"})
        self.assertEqual(p.errors["first_name"], ["This field is required."])
        self.assertEqual(p.errors["birthday"], ["This field is required."])
        self.assertFalse(p.is_valid())
        self.assertEqual(
            p.errors,
            {
                "birthday": ["This field is required."],
                "first_name": ["This field is required."],
            },
        )
        self.assertEqual(p.cleaned_data, {"last_name": "Lennon"})
        self.assertEqual(p["first_name"].errors, ["This field is required."])
        self.assertHTMLEqual(
            p["first_name"].errors.as_ul(),
            '<ul class="errorlist" id="id_first_name_error">'
            "<li>This field is required.</li></ul>",
        )
        self.assertEqual(p["first_name"].errors.as_text(), "* This field is required.")

        p = Person()
        self.assertHTMLEqual(
            str(p["first_name"]),
            '<input type="text" name="first_name" id="id_first_name" required>',
        )
        self.assertHTMLEqual(
            str(p["last_name"]),
            '<input type="text" name="last_name" id="id_last_name" required>',
        )
        self.assertHTMLEqual(
            str(p["birthday"]),
            '<input type="text" name="birthday" id="id_birthday" required>',
        )

    def test_cleaned_data_only_fields(self):
        # cleaned_data will always *only* contain a key for fields defined in
        # the Form, even if you pass extra data when you define the Form. In
        # this example, we pass a bunch of extra fields to the form
        # constructor, but cleaned_data contains only the form's fields.
        data = {
            "first_name": "John",
            "last_name": "Lennon",
            "birthday": "1940-10-9",
            "extra1": "hello",
            "extra2": "hello",
        }
        p = Person(data)
        self.assertTrue(p.is_valid())
        self.assertEqual(p.cleaned_data["first_name"], "John")
        self.assertEqual(p.cleaned_data["last_name"], "Lennon")
        self.assertEqual(p.cleaned_data["birthday"], datetime.date(1940, 10, 9))

    def test_optional_data(self):
        # cleaned_data will include a key and value for *all* fields defined in
        # the Form, even if the Form's data didn't include a value for fields
        # that are not required. In this example, the data dictionary doesn't
        # include a value for the "nick_name" field, but cleaned_data includes
        # it. For CharFields, it's set to the empty string.
        class OptionalPersonForm(Form):
            first_name = CharField()
            last_name = CharField()
            nick_name = CharField(required=False)

        data = {"first_name": "John", "last_name": "Lennon"}
        f = OptionalPersonForm(data)
        self.assertTrue(f.is_valid())
        self.assertEqual(f.cleaned_data["nick_name"], "")
        self.assertEqual(f.cleaned_data["first_name"], "John")
        self.assertEqual(f.cleaned_data["last_name"], "Lennon")

        # For DateFields, it's set to None.
        class OptionalPersonForm(Form):
            first_name = CharField()
            last_name = CharField()
            birth_date = DateField(required=False)

        data = {"first_name": "John", "last_name": "Lennon"}
        f = OptionalPersonForm(data)
        self.assertTrue(f.is_valid())
        self.assertIsNone(f.cleaned_data["birth_date"])
        self.assertEqual(f.cleaned_data["first_name"], "John")
        self.assertEqual(f.cleaned_data["last_name"], "Lennon")

    def test_auto_id(self):
        # "auto_id" tells the Form to add an "id" attribute to each form
        # element. If it's a string that contains '%s', Django will use that as
        # a format string into which the field's name will be inserted. It will
        # also put a <label> around the human-readable labels for a field.
        p = Person(auto_id="%s_id")
        self.assertHTMLEqual(
            p.as_table(),
            """<tr><th><label for="first_name_id">First name:</label></th><td>
<input type="text" name="first_name" id="first_name_id" required></td></tr>
<tr><th><label for="last_name_id">Last name:</label></th><td>
<input type="text" name="last_name" id="last_name_id" required></td></tr>
<tr><th><label for="birthday_id">Birthday:</label></th><td>
<input type="text" name="birthday" id="birthday_id" required></td></tr>""",
        )
        self.assertHTMLEqual(
            p.as_ul(),
            """<li><label for="first_name_id">First name:</label>
<input type="text" name="first_name" id="first_name_id" required></li>
<li><label for="last_name_id">Last name:</label>
<input type="text" name="last_name" id="last_name_id" required></li>
<li><label for="birthday_id">Birthday:</label>
<input type="text" name="birthday" id="birthday_id" required></li>""",
        )
        self.assertHTMLEqual(
            p.as_p(),
            """<p><label for="first_name_id">First name:</label>
<input type="text" name="first_name" id="first_name_id" required></p>
<p><label for="last_name_id">Last name:</label>
<input type="text" name="last_name" id="last_name_id" required></p>
<p><label for="birthday_id">Birthday:</label>
<input type="text" name="birthday" id="birthday_id" required></p>""",
        )
        self.assertHTMLEqual(
            p.as_div(),
            '<div><label for="first_name_id">First name:</label><input type="text" '
            'name="first_name" id="first_name_id" required></div><div><label '
            'for="last_name_id">Last name:</label><input type="text" '
            'name="last_name" id="last_name_id" required></div><div><label '
            'for="birthday_id">Birthday:</label><input type="text" name="birthday" '
            'id="birthday_id" required></div>',
        )

    def test_auto_id_true(self):
        # If auto_id is any True value whose str() does not contain '%s', the
        # "id" attribute will be the name of the field.
        p = Person(auto_id=True)
        self.assertHTMLEqual(
            p.as_ul(),
            """<li><label for="first_name">First name:</label>
<input type="text" name="first_name" id="first_name" required></li>
<li><label for="last_name">Last name:</label>
<input type="text" name="last_name" id="last_name" required></li>
<li><label for="birthday">Birthday:</label>
<input type="text" name="birthday" id="birthday" required></li>""",
        )

    def test_auto_id_false(self):
        # If auto_id is any False value, an "id" attribute won't be output
        # unless it was manually entered.
        p = Person(auto_id=False)
        self.assertHTMLEqual(
            p.as_ul(),
            """<li>First name: <input type="text" name="first_name" required></li>
<li>Last name: <input type="text" name="last_name" required></li>
<li>Birthday: <input type="text" name="birthday" required></li>""",
        )

    def test_id_on_field(self):
        # In this example, auto_id is False, but the "id" attribute for the
        # "first_name" field is given. Also note that field gets a <label>,
        # while the others don't.
        p = PersonNew(auto_id=False)
        self.assertHTMLEqual(
            p.as_ul(),
            """<li><label for="first_name_id">First name:</label>
<input type="text" id="first_name_id" name="first_name" required></li>
<li>Last name: <input type="text" name="last_name" required></li>
<li>Birthday: <input type="text" name="birthday" required></li>""",
        )

    def test_auto_id_on_form_and_field(self):
        # If the "id" attribute is specified in the Form and auto_id is True,
        # the "id" attribute in the Form gets precedence.
        p = PersonNew(auto_id=True)
        self.assertHTMLEqual(
            p.as_ul(),
            """<li><label for="first_name_id">First name:</label>
<input type="text" id="first_name_id" name="first_name" required></li>
<li><label for="last_name">Last name:</label>
<input type="text" name="last_name" id="last_name" required></li>
<li><label for="birthday">Birthday:</label>
<input type="text" name="birthday" id="birthday" required></li>""",
        )

    def test_various_boolean_values(self):
        class SignupForm(Form):
            email = EmailField()
            get_spam = BooleanField()

        f = SignupForm(auto_id=False)
        self.assertHTMLEqual(
            str(f["email"]),
            '<input type="email" name="email" maxlength="320" required>',
        )
        self.assertHTMLEqual(
            str(f["get_spam"]), '<input type="checkbox" name="get_spam" required>'
        )

        f = SignupForm({"email": "test@example.com", "get_spam": True}, auto_id=False)
        self.assertHTMLEqual(
            str(f["email"]),
            '<input type="email" name="email" maxlength="320" value="test@example.com" '
            "required>",
        )
        self.assertHTMLEqual(
            str(f["get_spam"]),
            '<input checked type="checkbox" name="get_spam" required>',
        )

        # 'True' or 'true' should be rendered without a value attribute
        f = SignupForm({"email": "test@example.com", "get_spam": "True"}, auto_id=False)
        self.assertHTMLEqual(
            str(f["get_spam"]),
            '<input checked type="checkbox" name="get_spam" required>',
        )

        f = SignupForm({"email": "test@example.com", "get_spam": "true"}, auto_id=False)
        self.assertHTMLEqual(
            str(f["get_spam"]),
            '<input checked type="checkbox" name="get_spam" required>',
        )

        # A value of 'False' or 'false' should be rendered unchecked
        f = SignupForm(
            {"email": "test@example.com", "get_spam": "False"}, auto_id=False
        )
        self.assertHTMLEqual(
            str(f["get_spam"]),
            '<input type="checkbox" name="get_spam" aria-invalid="true" required>',
        )

        f = SignupForm(
            {"email": "test@example.com", "get_spam": "false"}, auto_id=False
        )
        self.assertHTMLEqual(
            str(f["get_spam"]),
            '<input type="checkbox" name="get_spam" aria-invalid="true" required>',
        )

        # A value of '0' should be interpreted as a True value (#16820)
        f = SignupForm({"email": "test@example.com", "get_spam": "0"})
        self.assertTrue(f.is_valid())
        self.assertTrue(f.cleaned_data.get("get_spam"))

    def test_widget_output(self):
        # Any Field can have a Widget class passed to its constructor:
        class ContactForm(Form):
            subject = CharField()
            message = CharField(widget=Textarea)

        f = ContactForm(auto_id=False)
        self.assertHTMLEqual(
            str(f["subject"]), '<input type="text" name="subject" required>'
        )
        self.assertHTMLEqual(
            str(f["message"]),
            '<textarea name="message" rows="10" cols="40" required></textarea>',
        )

        # as_textarea(), as_text() and as_hidden() are shortcuts for changing
        # the output widget type:
        self.assertHTMLEqual(
            f["subject"].as_textarea(),
            '<textarea name="subject" rows="10" cols="40" required></textarea>',
        )
        self.assertHTMLEqual(
            f["message"].as_text(), '<input type="text" name="message" required>'
        )
        self.assertHTMLEqual(
            f["message"].as_hidden(), '<input type="hidden" name="message">'
        )

        # The 'widget' parameter to a Field can also be an instance:
        class ContactForm(Form):
            subject = CharField()
            message = CharField(widget=Textarea(attrs={"rows": 80, "cols": 20}))

        f = ContactForm(auto_id=False)
        self.assertHTMLEqual(
            str(f["message"]),
            '<textarea name="message" rows="80" cols="20" required></textarea>',
        )

        # Instance-level attrs are *not* carried over to as_textarea(),
        # as_text() and as_hidden():
        self.assertHTMLEqual(
            f["message"].as_text(), '<input type="text" name="message" required>'
        )
        f = ContactForm({"subject": "Hello", "message": "I love you."}, auto_id=False)
        self.assertHTMLEqual(
            f["subject"].as_textarea(),
            '<textarea rows="10" cols="40" name="subject" required>Hello</textarea>',
        )
        self.assertHTMLEqual(
            f["message"].as_text(),
            '<input type="text" name="message" value="I love you." required>',
        )
        self.assertHTMLEqual(
            f["message"].as_hidden(),
            '<input type="hidden" name="message" value="I love you.">',
        )

    def test_forms_with_choices(self):
        # For a form with a <select>, use ChoiceField:
        class FrameworkForm(Form):
            name = CharField()
            language = ChoiceField(choices=[("P", "Python"), ("J", "Java")])

        f = FrameworkForm(auto_id=False)
        self.assertHTMLEqual(
            str(f["language"]),
            """<select name="language">
<option value="P">Python</option>
<option value="J">Java</option>
</select>""",
        )
        f = FrameworkForm({"name": "Django", "language": "P"}, auto_id=False)
        self.assertHTMLEqual(
            str(f["language"]),
            """<select name="language">
<option value="P" selected>Python</option>
<option value="J">Java</option>
</select>""",
        )

        # A subtlety: If one of the choices' value is the empty string and the
        # form is unbound, then the <option> for the empty-string choice will
        # get selected.
        class FrameworkForm(Form):
            name = CharField()
            language = ChoiceField(
                choices=[("", "------"), ("P", "Python"), ("J", "Java")]
            )

        f = FrameworkForm(auto_id=False)
        self.assertHTMLEqual(
            str(f["language"]),
            """<select name="language" required>
<option value="" selected>------</option>
<option value="P">Python</option>
<option value="J">Java</option>
</select>""",
        )

        # You can specify widget attributes in the Widget constructor.
        class FrameworkForm(Form):
            name = CharField()
            language = ChoiceField(
                choices=[("P", "Python"), ("J", "Java")],
                widget=Select(attrs={"class": "foo"}),
            )

        f = FrameworkForm(auto_id=False)
        self.assertHTMLEqual(
            str(f["language"]),
            """<select class="foo" name="language">
<option value="P">Python</option>
<option value="J">Java</option>
</select>""",
        )
        f = FrameworkForm({"name": "Django", "language": "P"}, auto_id=False)
        self.assertHTMLEqual(
            str(f["language"]),
            """<select class="foo" name="language">
<option value="P" selected>Python</option>
<option value="J">Java</option>
</select>""",
        )

        # When passing a custom widget instance to ChoiceField, note that
        # setting 'choices' on the widget is meaningless. The widget will use
        # the choices defined on the Field, not the ones defined on the Widget.
        class FrameworkForm(Form):
            name = CharField()
            language = ChoiceField(
                choices=[("P", "Python"), ("J", "Java")],
                widget=Select(
                    choices=[("R", "Ruby"), ("P", "Perl")], attrs={"class": "foo"}
                ),
            )

        f = FrameworkForm(auto_id=False)
        self.assertHTMLEqual(
            str(f["language"]),
            """<select class="foo" name="language">
<option value="P">Python</option>
<option value="J">Java</option>
</select>""",
        )
        f = FrameworkForm({"name": "Django", "language": "P"}, auto_id=False)
        self.assertHTMLEqual(
            str(f["language"]),
            """<select class="foo" name="language">
<option value="P" selected>Python</option>
<option value="J">Java</option>
</select>""",
        )

        # You can set a ChoiceField's choices after the fact.
        class FrameworkForm(Form):
            name = CharField()
            language = ChoiceField()

        f = FrameworkForm(auto_id=False)
        self.assertHTMLEqual(
            str(f["language"]),
            """<select name="language">
</select>""",
        )
        f.fields["language"].choices = [("P", "Python"), ("J", "Java")]
        self.assertHTMLEqual(
            str(f["language"]),
            """<select name="language">
<option value="P">Python</option>
<option value="J">Java</option>
</select>""",
        )

    def test_forms_with_radio(self):
        # Add widget=RadioSelect to use that widget with a ChoiceField.
        f = FrameworkForm(auto_id=False)
        self.assertHTMLEqual(
            str(f["language"]),
            """<div>
<div><label><input type="radio" name="language" value="P" required> Python</label></div>
<div><label><input type="radio" name="language" value="J" required> Java</label></div>
</div>""",
        )
        self.assertHTMLEqual(
            f.as_table(),
            """<tr><th>Name:</th><td><input type="text" name="name" required></td></tr>
<tr><th>Language:</th><td><div>
<div><label><input type="radio" name="language" value="P" required> Python</label></div>
<div><label><input type="radio" name="language" value="J" required> Java</label></div>
</div></td></tr>""",
        )
        self.assertHTMLEqual(
            f.as_ul(),
            """<li>Name: <input type="text" name="name" required></li>
<li>Language: <div>
<div><label><input type="radio" name="language" value="P" required> Python</label></div>
<div><label><input type="radio" name="language" value="J" required> Java</label></div>
</div></li>""",
        )
        # Need an auto_id to generate legend.
        self.assertHTMLEqual(
            f.render(f.template_name_div),
            '<div> Name: <input type="text" name="name" required></div><div><fieldset>'
            'Language:<div><div><label><input type="radio" name="language" value="P" '
            'required> Python</label></div><div><label><input type="radio" '
            'name="language" value="J" required> Java</label></div></div></fieldset>'
            "</div>",
        )

        # Regarding auto_id and <label>, RadioSelect is a special case. Each
        # radio button gets a distinct ID, formed by appending an underscore
        # plus the button's zero-based index.
        f = FrameworkForm(auto_id="id_%s")
        self.assertHTMLEqual(
            str(f["language"]),
            """
            <div id="id_language">
            <div><label for="id_language_0">
            <input type="radio" id="id_language_0" value="P" name="language" required>
            Python</label></div>
            <div><label for="id_language_1">
            <input type="radio" id="id_language_1" value="J" name="language" required>
            Java</label></div>
            </div>""",
        )

        # When RadioSelect is used with auto_id, and the whole form is printed
        # using either as_table() or as_ul(), the label for the RadioSelect
        # will **not** point to the ID of the *first* radio button to improve
        # accessibility for screen reader users.
        self.assertHTMLEqual(
            f.as_table(),
            """
            <tr><th><label for="id_name">Name:</label></th><td>
            <input type="text" name="name" id="id_name" required></td></tr>
            <tr><th><label>Language:</label></th><td><div id="id_language">
            <div><label for="id_language_0">
            <input type="radio" id="id_language_0" value="P" name="language" required>
            Python</label></div>
            <div><label for="id_language_1">
            <input type="radio" id="id_language_1" value="J" name="language" required>
            Java</label></div>
            </div></td></tr>""",
        )
        self.assertHTMLEqual(
            f.as_ul(),
            """
            <li><label for="id_name">Name:</label>
            <input type="text" name="name" id="id_name" required></li>
            <li><label>Language:</label> <div id="id_language">
            <div><label for="id_language_0">
            <input type="radio" id="id_language_0" value="P" name="language" required>
            Python</label></div>
            <div><label for="id_language_1">
            <input type="radio" id="id_language_1" value="J" name="language" required>
            Java</label></div>
            </div></li>
            """,
        )
        self.assertHTMLEqual(
            f.as_p(),
            """
            <p><label for="id_name">Name:</label>
            <input type="text" name="name" id="id_name" required></p>
            <p><label>Language:</label> <div id="id_language">
            <div><label for="id_language_0">
            <input type="radio" id="id_language_0" value="P" name="language" required>
            Python</label></div>
            <div><label for="id_language_1">
            <input type="radio" id="id_language_1" value="J" name="language" required>
            Java</label></div>
            </div></p>
            """,
        )
        self.assertHTMLEqual(
            f.render(f.template_name_div),
            '<div><label for="id_name">Name:</label><input type="text" name="name" '
            'required id="id_name"></div><div><fieldset><legend>Language:</legend>'
            '<div id="id_language"><div><label for="id_language_0"><input '
            'type="radio" name="language" value="P" required id="id_language_0">'
            'Python</label></div><div><label for="id_language_1"><input type="radio" '
            'name="language" value="J" required id="id_language_1">Java</label></div>'
            "</div></fieldset></div>",
        )

    def test_form_with_iterable_boundfield(self):
        class BeatleForm(Form):
            name = ChoiceField(
                choices=[
                    ("john", "John"),
                    ("paul", "Paul"),
                    ("george", "George"),
                    ("ringo", "Ringo"),
                ],
                widget=RadioSelect,
            )

        f = BeatleForm(auto_id=False)
        self.assertHTMLEqual(
            "\n".join(str(bf) for bf in f["name"]),
            '<label><input type="radio" name="name" value="john" required> John</label>'
            '<label><input type="radio" name="name" value="paul" required> Paul</label>'
            '<label><input type="radio" name="name" value="george" required> George'
            "</label>"
            '<label><input type="radio" name="name" value="ringo" required> Ringo'
            "</label>",
        )
        self.assertHTMLEqual(
            "\n".join("<div>%s</div>" % bf for bf in f["name"]),
            """
            <div><label>
            <input type="radio" name="name" value="john" required> John</label></div>
            <div><label>
            <input type="radio" name="name" value="paul" required> Paul</label></div>
            <div><label>
            <input type="radio" name="name" value="george" required> George
            </label></div>
            <div><label>
            <input type="radio" name="name" value="ringo" required> Ringo</label></div>
            """,
        )

    def test_form_with_iterable_boundfield_id(self):
        class BeatleForm(Form):
            name = ChoiceField(
                choices=[
                    ("john", "John"),
                    ("paul", "Paul"),
                    ("george", "George"),
                    ("ringo", "Ringo"),
                ],
                widget=RadioSelect,
            )

        fields = list(BeatleForm()["name"])
        self.assertEqual(len(fields), 4)

        self.assertEqual(fields[0].id_for_label, "id_name_0")
        self.assertEqual(fields[0].choice_label, "John")
        self.assertHTMLEqual(
            fields[0].tag(),
            '<input type="radio" name="name" value="john" id="id_name_0" required>',
        )
        self.assertHTMLEqual(
            str(fields[0]),
            '<label for="id_name_0"><input type="radio" name="name" '
            'value="john" id="id_name_0" required> John</label>',
        )

        self.assertEqual(fields[1].id_for_label, "id_name_1")
        self.assertEqual(fields[1].choice_label, "Paul")
        self.assertHTMLEqual(
            fields[1].tag(),
            '<input type="radio" name="name" value="paul" id="id_name_1" required>',
        )
        self.assertHTMLEqual(
            str(fields[1]),
            '<label for="id_name_1"><input type="radio" name="name" '
            'value="paul" id="id_name_1" required> Paul</label>',
        )

    def test_iterable_boundfield_select(self):
        class BeatleForm(Form):
            name = ChoiceField(
                choices=[
                    ("john", "John"),
                    ("paul", "Paul"),
                    ("george", "George"),
                    ("ringo", "Ringo"),
                ]
            )

        fields = list(BeatleForm(auto_id=False)["name"])
        self.assertEqual(len(fields), 4)

        self.assertIsNone(fields[0].id_for_label)
        self.assertEqual(fields[0].choice_label, "John")
        self.assertHTMLEqual(fields[0].tag(), '<option value="john">John</option>')
        self.assertHTMLEqual(str(fields[0]), '<option value="john">John</option>')

    def test_form_with_noniterable_boundfield(self):
        # You can iterate over any BoundField, not just those with
        # widget=RadioSelect.
        class BeatleForm(Form):
            name = CharField()

        f = BeatleForm(auto_id=False)
        self.assertHTMLEqual(
            "\n".join(str(bf) for bf in f["name"]),
            '<input type="text" name="name" required>',
        )

    def test_boundfield_slice(self):
        class BeatleForm(Form):
            name = ChoiceField(
                choices=[
                    ("john", "John"),
                    ("paul", "Paul"),
                    ("george", "George"),
                    ("ringo", "Ringo"),
                ],
                widget=RadioSelect,
            )

        f = BeatleForm()
        bf = f["name"]
        self.assertEqual(
            [str(item) for item in bf[1:]],
            [str(bf[1]), str(bf[2]), str(bf[3])],
        )

    def test_boundfield_invalid_index(self):
        class TestForm(Form):
            name = ChoiceField(choices=[])

        field = TestForm()["name"]
        msg = "BoundField indices must be integers or slices, not str."
        with self.assertRaisesMessage(TypeError, msg):
            field["foo"]

    def test_boundfield_bool(self):
        """BoundField without any choices (subwidgets) evaluates to True."""

        class TestForm(Form):
            name = ChoiceField(choices=[])

        self.assertIs(bool(TestForm()["name"]), True)

    def test_forms_with_multiple_choice(self):
        # MultipleChoiceField is a special case, as its data is required to be
        # a list:
        class SongForm(Form):
            name = CharField()
            composers = MultipleChoiceField()

        f = SongForm(auto_id=False)
        self.assertHTMLEqual(
            str(f["composers"]),
            """<select multiple name="composers" required>
</select>""",
        )

        class SongForm(Form):
            name = CharField()
            composers = MultipleChoiceField(
                choices=[("J", "John Lennon"), ("P", "Paul McCartney")]
            )

        f = SongForm(auto_id=False)
        self.assertHTMLEqual(
            str(f["composers"]),
            """<select multiple name="composers" required>
<option value="J">John Lennon</option>
<option value="P">Paul McCartney</option>
</select>""",
        )
        f = SongForm({"name": "Yesterday", "composers": ["P"]}, auto_id=False)
        self.assertHTMLEqual(
            str(f["name"]), '<input type="text" name="name" value="Yesterday" required>'
        )
        self.assertHTMLEqual(
            str(f["composers"]),
            """<select multiple name="composers" required>
<option value="J">John Lennon</option>
<option value="P" selected>Paul McCartney</option>
</select>""",
        )
        f = SongForm()
        self.assertHTMLEqual(
            f.as_table(),
            '<tr><th><label for="id_name">Name:</label></th>'
            '<td><input type="text" name="name" required id="id_name"></td>'
            '</tr><tr><th><label for="id_composers">Composers:</label></th>'
            '<td><select name="composers" required id="id_composers" multiple>'
            '<option value="J">John Lennon</option>'
            '<option value="P">Paul McCartney</option>'
            "</select></td></tr>",
        )
        self.assertHTMLEqual(
            f.as_ul(),
            '<li><label for="id_name">Name:</label>'
            '<input type="text" name="name" required id="id_name"></li>'
            '<li><label for="id_composers">Composers:</label>'
            '<select name="composers" required id="id_composers" multiple>'
            '<option value="J">John Lennon</option>'
            '<option value="P">Paul McCartney</option>'
            "</select></li>",
        )
        self.assertHTMLEqual(
            f.as_p(),
            '<p><label for="id_name">Name:</label>'
            '<input type="text" name="name" required id="id_name"></p>'
            '<p><label for="id_composers">Composers:</label>'
            '<select name="composers" required id="id_composers" multiple>'
            '<option value="J">John Lennon</option>'
            '<option value="P">Paul McCartney</option>'
            "</select></p>",
        )
        self.assertHTMLEqual(
            f.render(f.template_name_div),
            '<div><label for="id_name">Name:</label><input type="text" name="name" '
            'required id="id_name"></div><div><label for="id_composers">Composers:'
            '</label><select name="composers" required id="id_composers" multiple>'
            '<option value="J">John Lennon</option><option value="P">Paul McCartney'
            "</option></select></div>",
        )

    def test_multiple_checkbox_render(self):
        f = SongForm()
        self.assertHTMLEqual(
            f.as_table(),
            '<tr><th><label for="id_name">Name:</label></th><td>'
            '<input type="text" name="name" required id="id_name"></td></tr>'
            '<tr><th><label>Composers:</label></th><td><div id="id_composers">'
            '<div><label for="id_composers_0">'
            '<input type="checkbox" name="composers" value="J" '
            'id="id_composers_0">John Lennon</label></div>'
            '<div><label for="id_composers_1">'
            '<input type="checkbox" name="composers" value="P" '
            'id="id_composers_1">Paul McCartney</label></div>'
            "</div></td></tr>",
        )
        self.assertHTMLEqual(
            f.as_ul(),
            '<li><label for="id_name">Name:</label>'
            '<input type="text" name="name" required id="id_name"></li>'
            '<li><label>Composers:</label><div id="id_composers">'
            '<div><label for="id_composers_0">'
            '<input type="checkbox" name="composers" value="J" '
            'id="id_composers_0">John Lennon</label></div>'
            '<div><label for="id_composers_1">'
            '<input type="checkbox" name="composers" value="P" '
            'id="id_composers_1">Paul McCartney</label></div>'
            "</div></li>",
        )
        self.assertHTMLEqual(
            f.as_p(),
            '<p><label for="id_name">Name:</label>'
            '<input type="text" name="name" required id="id_name"></p>'
            '<p><label>Composers:</label><div id="id_composers">'
            '<div><label for="id_composers_0">'
            '<input type="checkbox" name="composers" value="J" '
            'id="id_composers_0">John Lennon</label></div>'
            '<div><label for="id_composers_1">'
            '<input type="checkbox" name="composers" value="P" '
            'id="id_composers_1">Paul McCartney</label></div>'
            "</div></p>",
        )
        self.assertHTMLEqual(
            f.render(f.template_name_div),
            '<div><label for="id_name">Name:</label><input type="text" name="name" '
            'required id="id_name"></div><div><fieldset><legend>Composers:</legend>'
            '<div id="id_composers"><div><label for="id_composers_0"><input '
            'type="checkbox" name="composers" value="J" id="id_composers_0">'
            'John Lennon</label></div><div><label for="id_composers_1"><input '
            'type="checkbox" name="composers" value="P" id="id_composers_1">'
            "Paul McCartney</label></div></div></fieldset></div>",
        )

    def test_form_with_disabled_fields(self):
        class PersonForm(Form):
            name = CharField()
            birthday = DateField(disabled=True)

        class PersonFormFieldInitial(Form):
            name = CharField()
            birthday = DateField(disabled=True, initial=datetime.date(1974, 8, 16))

        # Disabled fields are generally not transmitted by user agents.
        # The value from the form's initial data is used.
        f1 = PersonForm(
            {"name": "John Doe"}, initial={"birthday": datetime.date(1974, 8, 16)}
        )
        f2 = PersonFormFieldInitial({"name": "John Doe"})
        for form in (f1, f2):
            self.assertTrue(form.is_valid())
            self.assertEqual(
                form.cleaned_data,
                {"birthday": datetime.date(1974, 8, 16), "name": "John Doe"},
            )

        # Values provided in the form's data are ignored.
        data = {"name": "John Doe", "birthday": "1984-11-10"}
        f1 = PersonForm(data, initial={"birthday": datetime.date(1974, 8, 16)})
        f2 = PersonFormFieldInitial(data)
        for form in (f1, f2):
            self.assertTrue(form.is_valid())
            self.assertEqual(
                form.cleaned_data,
                {"birthday": datetime.date(1974, 8, 16), "name": "John Doe"},
            )

        # Initial data remains present on invalid forms.
        data = {}
        f1 = PersonForm(data, initial={"birthday": datetime.date(1974, 8, 16)})
        f2 = PersonFormFieldInitial(data)
        for form in (f1, f2):
            self.assertFalse(form.is_valid())
            self.assertEqual(form["birthday"].value(), datetime.date(1974, 8, 16))

    def test_hidden_data(self):
        class SongForm(Form):
            name = CharField()
            composers = MultipleChoiceField(
                choices=[("J", "John Lennon"), ("P", "Paul McCartney")]
            )

        # MultipleChoiceField rendered as_hidden() is a special case. Because
        # it can have multiple values, its as_hidden() renders multiple <input
        # type="hidden"> tags.
        f = SongForm({"name": "Yesterday", "composers": ["P"]}, auto_id=False)
        self.assertHTMLEqual(
            f["composers"].as_hidden(),
            '<input type="hidden" name="composers" value="P">',
        )
        f = SongForm({"name": "From Me To You", "composers": ["P", "J"]}, auto_id=False)
        self.assertHTMLEqual(
            f["composers"].as_hidden(),
            """<input type="hidden" name="composers" value="P">
<input type="hidden" name="composers" value="J">""",
        )

        # DateTimeField rendered as_hidden() is special too
        class MessageForm(Form):
            when = SplitDateTimeField()

        f = MessageForm({"when_0": "1992-01-01", "when_1": "01:01"})
        self.assertTrue(f.is_valid())
        self.assertHTMLEqual(
            str(f["when"]),
            '<input type="text" name="when_0" value="1992-01-01" id="id_when_0" '
            "required>"
            '<input type="text" name="when_1" value="01:01" id="id_when_1" required>',
        )
        self.assertHTMLEqual(
            f["when"].as_hidden(),
            '<input type="hidden" name="when_0" value="1992-01-01" id="id_when_0">'
            '<input type="hidden" name="when_1" value="01:01" id="id_when_1">',
        )

    def test_multiple_choice_checkbox(self):
        # MultipleChoiceField can also be used with the CheckboxSelectMultiple
        # widget.
        f = SongForm(auto_id=False)
        self.assertHTMLEqual(
            str(f["composers"]),
            """
            <div>
            <div><label><input type="checkbox" name="composers" value="J">
            John Lennon</label></div>
            <div><label><input type="checkbox" name="composers" value="P">
            Paul McCartney</label></div>
            </div>
            """,
        )
        f = SongForm({"composers": ["J"]}, auto_id=False)
        self.assertHTMLEqual(
            str(f["composers"]),
            """
            <div>
            <div><label><input checked type="checkbox" name="composers" value="J">
            John Lennon</label></div>
            <div><label><input type="checkbox" name="composers" value="P">
            Paul McCartney</label></div>
            </div>
            """,
        )
        f = SongForm({"composers": ["J", "P"]}, auto_id=False)
        self.assertHTMLEqual(
            str(f["composers"]),
            """
            <div>
            <div><label><input checked type="checkbox" name="composers" value="J">
            John Lennon</label></div>
            <div><label><input checked type="checkbox" name="composers" value="P">
            Paul McCartney</label></div>
            </div>
            """,
        )

    def test_checkbox_auto_id(self):
        # Regarding auto_id, CheckboxSelectMultiple is a special case. Each
        # checkbox gets a distinct ID, formed by appending an underscore plus
        # the checkbox's zero-based index.
        class SongForm(Form):
            name = CharField()
            composers = MultipleChoiceField(
                choices=[("J", "John Lennon"), ("P", "Paul McCartney")],
                widget=CheckboxSelectMultiple,
            )

        f = SongForm(auto_id="%s_id")
        self.assertHTMLEqual(
            str(f["composers"]),
            """
            <div id="composers_id">
            <div><label for="composers_id_0">
            <input type="checkbox" name="composers" value="J" id="composers_id_0">
            John Lennon</label></div>
            <div><label for="composers_id_1">
            <input type="checkbox" name="composers" value="P" id="composers_id_1">
            Paul McCartney</label></div>
            </div>
            """,
        )

    def test_multiple_choice_list_data(self):
        # Data for a MultipleChoiceField should be a list. QueryDict and
        # MultiValueDict conveniently work with this.
        class SongForm(Form):
            name = CharField()
            composers = MultipleChoiceField(
                choices=[("J", "John Lennon"), ("P", "Paul McCartney")],
                widget=CheckboxSelectMultiple,
            )

        data = {"name": "Yesterday", "composers": ["J", "P"]}
        f = SongForm(data)
        self.assertEqual(f.errors, {})

        data = QueryDict("name=Yesterday&composers=J&composers=P")
        f = SongForm(data)
        self.assertEqual(f.errors, {})

        data = MultiValueDict({"name": ["Yesterday"], "composers": ["J", "P"]})
        f = SongForm(data)
        self.assertEqual(f.errors, {})

        # SelectMultiple uses ducktyping so that MultiValueDictLike.getlist()
        # is called.
        f = SongForm(MultiValueDictLike({"name": "Yesterday", "composers": "J"}))
        self.assertEqual(f.errors, {})
        self.assertEqual(f.cleaned_data["composers"], ["J"])

    def test_multiple_hidden(self):
        class SongForm(Form):
            name = CharField()
            composers = MultipleChoiceField(
                choices=[("J", "John Lennon"), ("P", "Paul McCartney")],
                widget=CheckboxSelectMultiple,
            )

        # The MultipleHiddenInput widget renders multiple values as hidden
        # fields.
        class SongFormHidden(Form):
            name = CharField()
            composers = MultipleChoiceField(
                choices=[("J", "John Lennon"), ("P", "Paul McCartney")],
                widget=MultipleHiddenInput,
            )

        f = SongFormHidden(
            MultiValueDict({"name": ["Yesterday"], "composers": ["J", "P"]}),
            auto_id=False,
        )
        self.assertHTMLEqual(
            f.as_ul(),
            """<li>Name: <input type="text" name="name" value="Yesterday" required>
<input type="hidden" name="composers" value="J">
<input type="hidden" name="composers" value="P"></li>""",
        )

        # When using CheckboxSelectMultiple, the framework expects a list of
        # input and returns a list of input.
        f = SongForm({"name": "Yesterday"}, auto_id=False)
        self.assertEqual(f.errors["composers"], ["This field is required."])
        f = SongForm({"name": "Yesterday", "composers": ["J"]}, auto_id=False)
        self.assertEqual(f.errors, {})
        self.assertEqual(f.cleaned_data["composers"], ["J"])
        self.assertEqual(f.cleaned_data["name"], "Yesterday")
        f = SongForm({"name": "Yesterday", "composers": ["J", "P"]}, auto_id=False)
        self.assertEqual(f.errors, {})
        self.assertEqual(f.cleaned_data["composers"], ["J", "P"])
        self.assertEqual(f.cleaned_data["name"], "Yesterday")

        # MultipleHiddenInput uses ducktyping so that
        # MultiValueDictLike.getlist() is called.
        f = SongForm(MultiValueDictLike({"name": "Yesterday", "composers": "J"}))
        self.assertEqual(f.errors, {})
        self.assertEqual(f.cleaned_data["composers"], ["J"])

    def test_escaping(self):
        # Validation errors are HTML-escaped when output as HTML.
        class EscapingForm(Form):
            special_name = CharField(label="<em>Special</em> Field")
            special_safe_name = CharField(label=mark_safe("<em>Special</em> Field"))

            def clean_special_name(self):
                raise ValidationError(
                    "Something's wrong with '%s'" % self.cleaned_data["special_name"]
                )

            def clean_special_safe_name(self):
                raise ValidationError(
                    mark_safe(
                        "'<b>%s</b>' is a safe string"
                        % self.cleaned_data["special_safe_name"]
                    )
                )

        f = EscapingForm(
            {
                "special_name": "Nothing to escape",
                "special_safe_name": "Nothing to escape",
            },
            auto_id=False,
        )
        self.assertHTMLEqual(
            f.as_table(),
            """
            <tr><th>&lt;em&gt;Special&lt;/em&gt; Field:</th><td>
            <ul class="errorlist">
            <li>Something&#x27;s wrong with &#x27;Nothing to escape&#x27;</li></ul>
            <input type="text" name="special_name" value="Nothing to escape"
            aria-invalid="true" required></td></tr>
            <tr><th><em>Special</em> Field:</th><td>
            <ul class="errorlist">
            <li>'<b>Nothing to escape</b>' is a safe string</li></ul>
            <input type="text" name="special_safe_name" value="Nothing to escape"
            aria-invalid="true" required></td></tr>
            """,
        )
        f = EscapingForm(
            {
                "special_name": "Should escape < & > and <script>alert('xss')</script>",
                "special_safe_name": "<i>Do not escape</i>",
            },
            auto_id=False,
        )
        self.assertHTMLEqual(
            f.as_table(),
            "<tr><th>&lt;em&gt;Special&lt;/em&gt; Field:</th><td>"
            '<ul class="errorlist"><li>'
            "Something&#x27;s wrong with &#x27;Should escape &lt; &amp; &gt; and "
            "&lt;script&gt;alert(&#x27;xss&#x27;)&lt;/script&gt;&#x27;</li></ul>"
            '<input type="text" name="special_name" value="Should escape &lt; &amp; '
            '&gt; and &lt;script&gt;alert(&#x27;xss&#x27;)&lt;/script&gt;" '
            'aria-invalid="true" required></td></tr>'
            "<tr><th><em>Special</em> Field:</th><td>"
            '<ul class="errorlist">'
            "<li>'<b><i>Do not escape</i></b>' is a safe string</li></ul>"
            '<input type="text" name="special_safe_name" '
            'value="&lt;i&gt;Do not escape&lt;/i&gt;" aria-invalid="true" required>'
            "</td></tr>",
        )

    def test_validating_multiple_fields(self):
        # There are a couple of ways to do multiple-field validation. If you
        # want the validation message to be associated with a particular field,
        # implement the clean_XXX() method on the Form, where XXX is the field
        # name. As in Field.clean(), the clean_XXX() method should return the
        # cleaned value. In the clean_XXX() method, you have access to
        # self.cleaned_data, which is a dictionary of all the data that has
        # been cleaned *so far*, in order by the fields, including the current
        # field (e.g., the field XXX if you're in clean_XXX()).
        class UserRegistration(Form):
            username = CharField(max_length=10)
            password1 = CharField(widget=PasswordInput)
            password2 = CharField(widget=PasswordInput)

            def clean_password2(self):
                if (
                    self.cleaned_data.get("password1")
                    and self.cleaned_data.get("password2")
                    and self.cleaned_data["password1"] != self.cleaned_data["password2"]
                ):
                    raise ValidationError("Please make sure your passwords match.")

                return self.cleaned_data["password2"]

        f = UserRegistration(auto_id=False)
        self.assertEqual(f.errors, {})
        f = UserRegistration({}, auto_id=False)
        self.assertEqual(f.errors["username"], ["This field is required."])
        self.assertEqual(f.errors["password1"], ["This field is required."])
        self.assertEqual(f.errors["password2"], ["This field is required."])
        f = UserRegistration(
            {"username": "adrian", "password1": "foo", "password2": "bar"},
            auto_id=False,
        )
        self.assertEqual(
            f.errors["password2"], ["Please make sure your passwords match."]
        )
        f = UserRegistration(
            {"username": "adrian", "password1": "foo", "password2": "foo"},
            auto_id=False,
        )
        self.assertEqual(f.errors, {})
        self.assertEqual(f.cleaned_data["username"], "adrian")
        self.assertEqual(f.cleaned_data["password1"], "foo")
        self.assertEqual(f.cleaned_data["password2"], "foo")

        # Another way of doing multiple-field validation is by implementing the
        # Form's clean() method. Usually ValidationError raised by that method
        # will not be associated with a particular field and will have a
        # special-case association with the field named '__all__'. It's
        # possible to associate the errors to particular field with the
        # Form.add_error() method or by passing a dictionary that maps each
        # field to one or more errors.
        #
        # Note that in Form.clean(), you have access to self.cleaned_data, a
        # dictionary of all the fields/values that have *not* raised a
        # ValidationError. Also note Form.clean() is required to return a
        # dictionary of all clean data.
        class UserRegistration(Form):
            username = CharField(max_length=10)
            password1 = CharField(widget=PasswordInput)
            password2 = CharField(widget=PasswordInput)

            def clean(self):
                # Test raising a ValidationError as NON_FIELD_ERRORS.
                if (
                    self.cleaned_data.get("password1")
                    and self.cleaned_data.get("password2")
                    and self.cleaned_data["password1"] != self.cleaned_data["password2"]
                ):
                    raise ValidationError("Please make sure your passwords match.")

                # Test raising ValidationError that targets multiple fields.
                errors = {}
                if self.cleaned_data.get("password1") == "FORBIDDEN_VALUE":
                    errors["password1"] = "Forbidden value."
                if self.cleaned_data.get("password2") == "FORBIDDEN_VALUE":
                    errors["password2"] = ["Forbidden value."]
                if errors:
                    raise ValidationError(errors)

                # Test Form.add_error()
                if self.cleaned_data.get("password1") == "FORBIDDEN_VALUE2":
                    self.add_error(None, "Non-field error 1.")
                    self.add_error("password1", "Forbidden value 2.")
                if self.cleaned_data.get("password2") == "FORBIDDEN_VALUE2":
                    self.add_error("password2", "Forbidden value 2.")
                    raise ValidationError("Non-field error 2.")

                return self.cleaned_data

        f = UserRegistration(auto_id=False)
        self.assertEqual(f.errors, {})

        f = UserRegistration({}, auto_id=False)
        self.assertHTMLEqual(
            f.as_table(),
            """<tr><th>Username:</th><td>
<ul class="errorlist"><li>This field is required.</li></ul>
<input type="text" name="username" maxlength="10" aria-invalid="true" required>
</td></tr>
<tr><th>Password1:</th><td><ul class="errorlist"><li>This field is required.</li></ul>
<input type="password" name="password1" aria-invalid="true" required></td></tr>
<tr><th>Password2:</th><td><ul class="errorlist"><li>This field is required.</li></ul>
<input type="password" name="password2" aria-invalid="true" required></td></tr>""",
        )
        self.assertEqual(f.errors["username"], ["This field is required."])
        self.assertEqual(f.errors["password1"], ["This field is required."])
        self.assertEqual(f.errors["password2"], ["This field is required."])

        f = UserRegistration(
            {"username": "adrian", "password1": "foo", "password2": "bar"},
            auto_id=False,
        )
        self.assertEqual(
            f.errors["__all__"], ["Please make sure your passwords match."]
        )
        self.assertHTMLEqual(
            f.as_table(),
            """
            <tr><td colspan="2">
            <ul class="errorlist nonfield">
            <li>Please make sure your passwords match.</li></ul></td></tr>
            <tr><th>Username:</th><td>
            <input type="text" name="username" value="adrian" maxlength="10" required>
            </td></tr>
            <tr><th>Password1:</th><td>
            <input type="password" name="password1" required></td></tr>
            <tr><th>Password2:</th><td>
            <input type="password" name="password2" required></td></tr>
            """,
        )
        self.assertHTMLEqual(
            f.as_ul(),
            """
            <li><ul class="errorlist nonfield">
            <li>Please make sure your passwords match.</li></ul></li>
            <li>Username:
            <input type="text" name="username" value="adrian" maxlength="10" required>
            </li>
            <li>Password1: <input type="password" name="password1" required></li>
            <li>Password2: <input type="password" name="password2" required></li>
            """,
        )
        self.assertHTMLEqual(
            f.render(f.template_name_div),
            '<ul class="errorlist nonfield"><li>Please make sure your passwords match.'
            '</li></ul><div>Username: <input type="text" name="username" '
            'value="adrian" maxlength="10" required></div><div>Password1: <input '
            'type="password" name="password1" required></div><div>Password2: <input '
            'type="password" name="password2" required></div>',
        )

        f = UserRegistration(
            {"username": "adrian", "password1": "foo", "password2": "foo"},
            auto_id=False,
        )
        self.assertEqual(f.errors, {})
        self.assertEqual(f.cleaned_data["username"], "adrian")
        self.assertEqual(f.cleaned_data["password1"], "foo")
        self.assertEqual(f.cleaned_data["password2"], "foo")

        f = UserRegistration(
            {
                "username": "adrian",
                "password1": "FORBIDDEN_VALUE",
                "password2": "FORBIDDEN_VALUE",
            },
            auto_id=False,
        )
        self.assertEqual(f.errors["password1"], ["Forbidden value."])
        self.assertEqual(f.errors["password2"], ["Forbidden value."])

        f = UserRegistration(
            {
                "username": "adrian",
                "password1": "FORBIDDEN_VALUE2",
                "password2": "FORBIDDEN_VALUE2",
            },
            auto_id=False,
        )
        self.assertEqual(
            f.errors["__all__"], ["Non-field error 1.", "Non-field error 2."]
        )
        self.assertEqual(f.errors["password1"], ["Forbidden value 2."])
        self.assertEqual(f.errors["password2"], ["Forbidden value 2."])

        with self.assertRaisesMessage(ValueError, "has no field named"):
            f.add_error("missing_field", "Some error.")

    def test_update_error_dict(self):
        class CodeForm(Form):
            code = CharField(max_length=10)

            def clean(self):
                try:
                    raise ValidationError({"code": [ValidationError("Code error 1.")]})
                except ValidationError as e:
                    self._errors = e.update_error_dict(self._errors)

                try:
                    raise ValidationError({"code": [ValidationError("Code error 2.")]})
                except ValidationError as e:
                    self._errors = e.update_error_dict(self._errors)

                try:
                    raise ValidationError({"code": ErrorList(["Code error 3."])})
                except ValidationError as e:
                    self._errors = e.update_error_dict(self._errors)

                try:
                    raise ValidationError("Non-field error 1.")
                except ValidationError as e:
                    self._errors = e.update_error_dict(self._errors)

                try:
                    raise ValidationError([ValidationError("Non-field error 2.")])
                except ValidationError as e:
                    self._errors = e.update_error_dict(self._errors)

                # The newly added list of errors is an instance of ErrorList.
                for field, error_list in self._errors.items():
                    if not isinstance(error_list, self.error_class):
                        self._errors[field] = self.error_class(error_list)

        form = CodeForm({"code": "hello"})
        # Trigger validation.
        self.assertFalse(form.is_valid())

        # update_error_dict didn't lose track of the ErrorDict type.
        self.assertIsInstance(form._errors, ErrorDict)

        self.assertEqual(
            dict(form.errors),
            {
                "code": ["Code error 1.", "Code error 2.", "Code error 3."],
                NON_FIELD_ERRORS: ["Non-field error 1.", "Non-field error 2."],
            },
        )

    def test_has_error(self):
        class UserRegistration(Form):
            username = CharField(max_length=10)
            password1 = CharField(widget=PasswordInput, min_length=5)
            password2 = CharField(widget=PasswordInput)

            def clean(self):
                if (
                    self.cleaned_data.get("password1")
                    and self.cleaned_data.get("password2")
                    and self.cleaned_data["password1"] != self.cleaned_data["password2"]
                ):
                    raise ValidationError(
                        "Please make sure your passwords match.",
                        code="password_mismatch",
                    )

        f = UserRegistration(data={})
        self.assertTrue(f.has_error("password1"))
        self.assertTrue(f.has_error("password1", "required"))
        self.assertFalse(f.has_error("password1", "anything"))

        f = UserRegistration(data={"password1": "Hi", "password2": "Hi"})
        self.assertTrue(f.has_error("password1"))
        self.assertTrue(f.has_error("password1", "min_length"))
        self.assertFalse(f.has_error("password1", "anything"))
        self.assertFalse(f.has_error("password2"))
        self.assertFalse(f.has_error("password2", "anything"))

        f = UserRegistration(data={"password1": "Bonjour", "password2": "Hello"})
        self.assertFalse(f.has_error("password1"))
        self.assertFalse(f.has_error("password1", "required"))
        self.assertTrue(f.has_error(NON_FIELD_ERRORS))
        self.assertTrue(f.has_error(NON_FIELD_ERRORS, "password_mismatch"))
        self.assertFalse(f.has_error(NON_FIELD_ERRORS, "anything"))

    def test_html_output_with_hidden_input_field_errors(self):
        class TestForm(Form):
            hidden_input = CharField(widget=HiddenInput)

            def clean(self):
                self.add_error(None, "Form error")

        f = TestForm(data={})
        error_dict = {
            "hidden_input": ["This field is required."],
            "__all__": ["Form error"],
        }
        self.assertEqual(f.errors, error_dict)
        f.as_table()
        self.assertEqual(f.errors, error_dict)
        self.assertHTMLEqual(
            f.as_table(),
            '<tr><td colspan="2"><ul class="errorlist nonfield"><li>Form error</li>'
            "<li>(Hidden field hidden_input) This field is required.</li></ul>"
            '<input type="hidden" name="hidden_input" id="id_hidden_input"></td></tr>',
        )
        self.assertHTMLEqual(
            f.as_ul(),
            '<li><ul class="errorlist nonfield"><li>Form error</li>'
            "<li>(Hidden field hidden_input) This field is required.</li></ul>"
            '<input type="hidden" name="hidden_input" id="id_hidden_input"></li>',
        )
        self.assertHTMLEqual(
            f.as_p(),
            '<ul class="errorlist nonfield"><li>Form error</li>'
            "<li>(Hidden field hidden_input) This field is required.</li></ul>"
            '<p><input type="hidden" name="hidden_input" id="id_hidden_input"></p>',
        )
        self.assertHTMLEqual(
            f.render(f.template_name_div),
            '<ul class="errorlist nonfield"><li>Form error</li>'
            "<li>(Hidden field hidden_input) This field is required.</li></ul>"
            '<div><input type="hidden" name="hidden_input" id="id_hidden_input"></div>',
        )

    def test_dynamic_construction(self):
        # It's possible to construct a Form dynamically by adding to the
        # self.fields dictionary in __init__(). Don't forget to call
        # Form.__init__() within the subclass' __init__().
        class Person(Form):
            first_name = CharField()
            last_name = CharField()

            def __init__(self, *args, **kwargs):
                super().__init__(*args, **kwargs)
                self.fields["birthday"] = DateField()

        p = Person(auto_id=False)
        self.assertHTMLEqual(
            p.as_table(),
            """
            <tr><th>First name:</th><td>
            <input type="text" name="first_name" required></td></tr>
            <tr><th>Last name:</th><td>
            <input type="text" name="last_name" required></td></tr>
            <tr><th>Birthday:</th><td>
            <input type="text" name="birthday" required></td></tr>
            """,
        )

        # Instances of a dynamic Form do not persist fields from one Form
        # instance to the next.
        class MyForm(Form):
            def __init__(self, data=None, auto_id=False, field_list=[]):
                Form.__init__(self, data, auto_id=auto_id)

                for field in field_list:
                    self.fields[field[0]] = field[1]

        field_list = [("field1", CharField()), ("field2", CharField())]
        my_form = MyForm(field_list=field_list)
        self.assertHTMLEqual(
            my_form.as_table(),
            """
            <tr><th>Field1:</th><td><input type="text" name="field1" required></td></tr>
            <tr><th>Field2:</th><td><input type="text" name="field2" required></td></tr>
            """,
        )
        field_list = [("field3", CharField()), ("field4", CharField())]
        my_form = MyForm(field_list=field_list)
        self.assertHTMLEqual(
            my_form.as_table(),
            """
            <tr><th>Field3:</th><td><input type="text" name="field3" required></td></tr>
            <tr><th>Field4:</th><td><input type="text" name="field4" required></td></tr>
            """,
        )

        class MyForm(Form):
            default_field_1 = CharField()
            default_field_2 = CharField()

            def __init__(self, data=None, auto_id=False, field_list=[]):
                Form.__init__(self, data, auto_id=auto_id)

                for field in field_list:
                    self.fields[field[0]] = field[1]

        field_list = [("field1", CharField()), ("field2", CharField())]
        my_form = MyForm(field_list=field_list)
        self.assertHTMLEqual(
            my_form.as_table(),
            """
            <tr><th>Default field 1:</th><td>
            <input type="text" name="default_field_1" required></td></tr>
            <tr><th>Default field 2:</th><td>
            <input type="text" name="default_field_2" required></td></tr>
            <tr><th>Field1:</th><td><input type="text" name="field1" required></td></tr>
            <tr><th>Field2:</th><td><input type="text" name="field2" required></td></tr>
            """,
        )
        field_list = [("field3", CharField()), ("field4", CharField())]
        my_form = MyForm(field_list=field_list)
        self.assertHTMLEqual(
            my_form.as_table(),
            """
            <tr><th>Default field 1:</th><td>
            <input type="text" name="default_field_1" required></td></tr>
            <tr><th>Default field 2:</th><td>
            <input type="text" name="default_field_2" required></td></tr>
            <tr><th>Field3:</th><td><input type="text" name="field3" required></td></tr>
            <tr><th>Field4:</th><td><input type="text" name="field4" required></td></tr>
            """,
        )

        # Similarly, changes to field attributes do not persist from one Form
        # instance to the next.
        class Person(Form):
            first_name = CharField(required=False)
            last_name = CharField(required=False)

            def __init__(self, names_required=False, *args, **kwargs):
                super().__init__(*args, **kwargs)

                if names_required:
                    self.fields["first_name"].required = True
                    self.fields["first_name"].widget.attrs["class"] = "required"
                    self.fields["last_name"].required = True
                    self.fields["last_name"].widget.attrs["class"] = "required"

        f = Person(names_required=False)
        self.assertEqual(
            f["first_name"].field.required,
            f["last_name"].field.required,
            (False, False),
        )
        self.assertEqual(
            f["first_name"].field.widget.attrs,
            f["last_name"].field.widget.attrs,
            ({}, {}),
        )
        f = Person(names_required=True)
        self.assertEqual(
            f["first_name"].field.required, f["last_name"].field.required, (True, True)
        )
        self.assertEqual(
            f["first_name"].field.widget.attrs,
            f["last_name"].field.widget.attrs,
            ({"class": "reuired"}, {"class": "required"}),
        )
        f = Person(names_required=False)
        self.assertEqual(
            f["first_name"].field.required,
            f["last_name"].field.required,
            (False, False),
        )
        self.assertEqual(
            f["first_name"].field.widget.attrs,
            f["last_name"].field.widget.attrs,
            ({}, {}),
        )

        class Person(Form):
            first_name = CharField(max_length=30)
            last_name = CharField(max_length=30)

            def __init__(self, name_max_length=None, *args, **kwargs):
                super().__init__(*args, **kwargs)

                if name_max_length:
                    self.fields["first_name"].max_length = name_max_length
                    self.fields["last_name"].max_length = name_max_length

        f = Person(name_max_length=None)
        self.assertEqual(
            f["first_name"].field.max_length, f["last_name"].field.max_length, (30, 30)
        )
        f = Person(name_max_length=20)
        self.assertEqual(
            f["first_name"].field.max_length, f["last_name"].field.max_length, (20, 20)
        )
        f = Person(name_max_length=None)
        self.assertEqual(
            f["first_name"].field.max_length, f["last_name"].field.max_length, (30, 30)
        )

        # Similarly, choices do not persist from one Form instance to the next.
        # Refs #15127.
        class Person(Form):
            first_name = CharField(required=False)
            last_name = CharField(required=False)
            gender = ChoiceField(choices=(("f", "Female"), ("m", "Male")))

            def __init__(self, allow_unspec_gender=False, *args, **kwargs):
                super().__init__(*args, **kwargs)

                if allow_unspec_gender:
                    self.fields["gender"].choices += (("u", "Unspecified"),)

        f = Person()
        self.assertEqual(f["gender"].field.choices, [("f", "Female"), ("m", "Male")])
        f = Person(allow_unspec_gender=True)
        self.assertEqual(
            f["gender"].field.choices,
            [("f", "Female"), ("m", "Male"), ("u", "Unspecified")],
        )
        f = Person()
        self.assertEqual(f["gender"].field.choices, [("f", "Female"), ("m", "Male")])

    def test_validators_independence(self):
        """
        The list of form field validators can be modified without polluting
        other forms.
        """

        class MyForm(Form):
            myfield = CharField(max_length=25)

        f1 = MyForm()
        f2 = MyForm()

        f1.fields["myfield"].validators[0] = MaxValueValidator(12)
        self.assertNotEqual(
            f1.fields["myfield"].validators[0], f2.fields["myfield"].validators[0]
        )

    def test_hidden_widget(self):
        # HiddenInput widgets are displayed differently in the as_table(),
        # as_ul()) and as_p() output of a Form -- their verbose names are not
        # displayed, and a separate row is not displayed. They're displayed in
        # the last row of the form, directly after that row's form element.
        class Person(Form):
            first_name = CharField()
            last_name = CharField()
            hidden_text = CharField(widget=HiddenInput)
            birthday = DateField()

        p = Person(auto_id=False)
        self.assertHTMLEqual(
            p.as_table(),
            """
            <tr><th>First name:</th><td><input type="text" name="first_name" required>
            </td></tr>
            <tr><th>Last name:</th><td><input type="text" name="last_name" required>
            </td></tr>
            <tr><th>Birthday:</th>
            <td><input type="text" name="birthday" required>
            <input type="hidden" name="hidden_text"></td></tr>
            """,
        )
        self.assertHTMLEqual(
            p.as_ul(),
            """
            <li>First name: <input type="text" name="first_name" required></li>
            <li>Last name: <input type="text" name="last_name" required></li>
            <li>Birthday: <input type="text" name="birthday" required>
            <input type="hidden" name="hidden_text"></li>
            """,
        )
        self.assertHTMLEqual(
            p.as_p(),
            """
            <p>First name: <input type="text" name="first_name" required></p>
            <p>Last name: <input type="text" name="last_name" required></p>
            <p>Birthday: <input type="text" name="birthday" required>
            <input type="hidden" name="hidden_text"></p>
            """,
        )
        self.assertHTMLEqual(
            p.as_div(),
            '<div>First name: <input type="text" name="first_name" required></div>'
            '<div>Last name: <input type="text" name="last_name" required></div><div>'
            'Birthday: <input type="text" name="birthday" required><input '
            'type="hidden" name="hidden_text"></div>',
        )

        # With auto_id set, a HiddenInput still gets an ID, but it doesn't get
        # a label.
        p = Person(auto_id="id_%s")
        self.assertHTMLEqual(
            p.as_table(),
            """<tr><th><label for="id_first_name">First name:</label></th><td>
<input type="text" name="first_name" id="id_first_name" required></td></tr>
<tr><th><label for="id_last_name">Last name:</label></th><td>
<input type="text" name="last_name" id="id_last_name" required></td></tr>
<tr><th><label for="id_birthday">Birthday:</label></th><td>
<input type="text" name="birthday" id="id_birthday" required>
<input type="hidden" name="hidden_text" id="id_hidden_text"></td></tr>""",
        )
        self.assertHTMLEqual(
            p.as_ul(),
            """<li><label for="id_first_name">First name:</label>
<input type="text" name="first_name" id="id_first_name" required></li>
<li><label for="id_last_name">Last name:</label>
<input type="text" name="last_name" id="id_last_name" required></li>
<li><label for="id_birthday">Birthday:</label>
<input type="text" name="birthday" id="id_birthday" required>
<input type="hidden" name="hidden_text" id="id_hidden_text"></li>""",
        )
        self.assertHTMLEqual(
            p.as_p(),
            """<p><label for="id_first_name">First name:</label>
<input type="text" name="first_name" id="id_first_name" required></p>
<p><label for="id_last_name">Last name:</label>
<input type="text" name="last_name" id="id_last_name" required></p>
<p><label for="id_birthday">Birthday:</label>
<input type="text" name="birthday" id="id_birthday" required>
<input type="hidden" name="hidden_text" id="id_hidden_text"></p>""",
        )
        self.assertHTMLEqual(
            p.as_div(),
            '<div><label for="id_first_name">First name:</label><input type="text" '
            'name="first_name" id="id_first_name" required></div><div><label '
            'for="id_last_name">Last name:</label><input type="text" name="last_name" '
            'id="id_last_name" required></div><div><label for="id_birthday">Birthday:'
            '</label><input type="text" name="birthday" id="id_birthday" required>'
            '<input type="hidden" name="hidden_text" id="id_hidden_text"></div>',
        )

        # If a field with a HiddenInput has errors, the as_table() and as_ul()
        # output will include the error message(s) with the text "(Hidden field
        # [fieldname]) " prepended. This message is displayed at the top of the
        # output, regardless of its field's order in the form.
        p = Person(
            {"first_name": "John", "last_name": "Lennon", "birthday": "1940-10-9"},
            auto_id=False,
        )
        self.assertHTMLEqual(
            p.as_table(),
            """
            <tr><td colspan="2">
            <ul class="errorlist nonfield"><li>
            (Hidden field hidden_text) This field is required.</li></ul></td></tr>
            <tr><th>First name:</th><td>
            <input type="text" name="first_name" value="John" required></td></tr>
            <tr><th>Last name:</th><td>
            <input type="text" name="last_name" value="Lennon" required></td></tr>
            <tr><th>Birthday:</th><td>
            <input type="text" name="birthday" value="1940-10-9" required>
            <input type="hidden" name="hidden_text"></td></tr>
            """,
        )
        self.assertHTMLEqual(
            p.as_ul(),
            """
            <li><ul class="errorlist nonfield"><li>
            (Hidden field hidden_text) This field is required.</li></ul></li>
            <li>First name: <input type="text" name="first_name" value="John" required>
            </li>
            <li>Last name: <input type="text" name="last_name" value="Lennon" required>
            </li>
            <li>Birthday: <input type="text" name="birthday" value="1940-10-9" required>
            <input type="hidden" name="hidden_text"></li>
            """,
        )
        self.assertHTMLEqual(
            p.as_p(),
            """
            <ul class="errorlist nonfield"><li>
            (Hidden field hidden_text) This field is required.</li></ul>
            <p>First name: <input type="text" name="first_name" value="John" required>
            </p>
            <p>Last name: <input type="text" name="last_name" value="Lennon" required>
            </p>
            <p>Birthday: <input type="text" name="birthday" value="1940-10-9" required>
            <input type="hidden" name="hidden_text"></p>
            """,
        )
        self.assertHTMLEqual(
            p.as_div(),
            '<ul class="errorlist nonfield"><li>(Hidden field hidden_text) This field '
            'is required.</li></ul><div>First name: <input type="text" '
            'name="first_name" value="John" required></div><div>Last name: <input '
            'type="text" name="last_name" value="Lennon" required></div><div>'
            'Birthday: <input type="text" name="birthday" value="1940-10-9" required>'
            '<input type="hidden" name="hidden_text"></div>',
        )

        # A corner case: It's possible for a form to have only HiddenInputs.
        class TestForm(Form):
            foo = CharField(widget=HiddenInput)
            bar = CharField(widget=HiddenInput)

        p = TestForm(auto_id=False)
        self.assertHTMLEqual(
            p.as_table(),
            '<input type="hidden" name="foo"><input type="hidden" name="bar">',
        )
        self.assertHTMLEqual(
            p.as_ul(),
            '<input type="hidden" name="foo"><input type="hidden" name="bar">',
        )
        self.assertHTMLEqual(
            p.as_p(), '<input type="hidden" name="foo"><input type="hidden" name="bar">'
        )

    def test_hidden_widget_does_not_have_aria_describedby(self):
        class TestForm(Form):
            hidden_text = CharField(widget=HiddenInput, help_text="Help Text")

        f = TestForm()
        self.assertEqual(
            str(f), '<input type="hidden" name="hidden_text" id="id_hidden_text">'
        )

    def test_field_order(self):
        # A Form's fields are displayed in the same order in which they were
        # defined.
        class TestForm(Form):
            field1 = CharField()
            field2 = CharField()
            field3 = CharField()
            field4 = CharField()
            field5 = CharField()
            field6 = CharField()
            field7 = CharField()
            field8 = CharField()
            field9 = CharField()
            field10 = CharField()
            field11 = CharField()
            field12 = CharField()
            field13 = CharField()
            field14 = CharField()

        p = TestForm(auto_id=False)
        self.assertHTMLEqual(
            p.as_table(),
            "".join(
                f"<tr><th>Field{i}:</th><td>"
                f'<input type="text" name="field{i}" required></td></tr>'
                for i in range(1, 15)
            ),
        )

    def test_explicit_field_order(self):
        class TestFormParent(Form):
            field1 = CharField()
            field2 = CharField()
            field4 = CharField()
            field5 = CharField()
            field6 = CharField()
            field_order = ["field6", "field5", "field4", "field2", "field1"]

        class TestForm(TestFormParent):
            field3 = CharField()
            field_order = ["field2", "field4", "field3", "field5", "field6"]

        class TestFormRemove(TestForm):
            field1 = None

        class TestFormMissing(TestForm):
            field_order = ["field2", "field4", "field3", "field5", "field6", "field1"]
            field1 = None

        class TestFormInit(TestFormParent):
            field3 = CharField()
            field_order = None

            def __init__(self, **kwargs):
                super().__init__(**kwargs)
                self.order_fields(field_order=TestForm.field_order)

        p = TestFormParent()
        self.assertEqual(list(p.fields), TestFormParent.field_order)
        p = TestFormRemove()
        self.assertEqual(list(p.fields), TestForm.field_order)
        p = TestFormMissing()
        self.assertEqual(list(p.fields), TestForm.field_order)
        p = TestForm()
        self.assertEqual(list(p.fields), TestFormMissing.field_order)
        p = TestFormInit()
        order = [*TestForm.field_order, "field1"]
        self.assertEqual(list(p.fields), order)
        TestForm.field_order = ["unknown"]
        p = TestForm()
        self.assertEqual(
            list(p.fields), ["field1", "field2", "field4", "field5", "field6", "field3"]
        )

    def test_form_html_attributes(self):
        # Some Field classes have an effect on the HTML attributes of their
        # associated Widget. If you set max_length in a CharField and its
        # associated widget is either a TextInput or PasswordInput, then the
        # widget's rendered HTML will include the "maxlength" attribute.
        class UserRegistration(Form):
            username = CharField(max_length=10)  # uses TextInput by default
            password = CharField(max_length=10, widget=PasswordInput)
            realname = CharField(
                max_length=10, widget=TextInput
            )  # redundantly define widget, just to test
            address = CharField()  # no max_length defined here

        p = UserRegistration(auto_id=False)
        self.assertHTMLEqual(
            p.as_ul(),
            """
            <li>Username: <input type="text" name="username" maxlength="10" required>
            </li>
            <li>Password: <input type="password" name="password" maxlength="10"
                required></li>
            <li>Realname: <input type="text" name="realname" maxlength="10" required>
            </li>
            <li>Address: <input type="text" name="address" required></li>
            """,
        )

        # If you specify a custom "attrs" that includes the "maxlength"
        # attribute, the Field's max_length attribute will override whatever
        # "maxlength" you specify in "attrs".
        class UserRegistration(Form):
            username = CharField(
                max_length=10, widget=TextInput(attrs={"maxlength": 20})
            )
            password = CharField(max_length=10, widget=PasswordInput)

        p = UserRegistration(auto_id=False)
        self.assertHTMLEqual(
            p.as_ul(),
            '<li>Username: <input type="text" name="username" maxlength="10" required>'
            "</li>"
            '<li>Password: <input type="password" name="password" maxlength="10" '
            "required></li>",
        )

    def test_specifying_labels(self):
        # You can specify the label for a field by using the 'label' argument
        # to a Field class. If you don't specify 'label', Django will use the
        # field name with underscores converted to spaces, and the initial
        # letter capitalized.
        class UserRegistration(Form):
            username = CharField(max_length=10, label="Your username")
            password1 = CharField(widget=PasswordInput)
            password2 = CharField(widget=PasswordInput, label="Contraseña (de nuevo)")

        p = UserRegistration(auto_id=False)
        self.assertHTMLEqual(
            p.as_ul(),
            """
            <li>Your username:
            <input type="text" name="username" maxlength="10" required></li>
            <li>Password1: <input type="password" name="password1" required></li>
            <li>Contraseña (de nuevo):
            <input type="password" name="password2" required></li>
            """,
        )

        # Labels for as_* methods will only end in a colon if they don't end in
        # other punctuation already.
        class Questions(Form):
            q1 = CharField(label="The first question")
            q2 = CharField(label="What is your name?")
            q3 = CharField(label="The answer to life is:")
            q4 = CharField(label="Answer this question!")
            q5 = CharField(label="The last question. Period.")

        self.assertHTMLEqual(
            Questions(auto_id=False).as_p(),
            """<p>The first question: <input type="text" name="q1" required></p>
<p>What is your name? <input type="text" name="q2" required></p>
<p>The answer to life is: <input type="text" name="q3" required></p>
<p>Answer this question! <input type="text" name="q4" required></p>
<p>The last question. Period. <input type="text" name="q5" required></p>""",
        )
        self.assertHTMLEqual(
            Questions().as_p(),
            """
            <p><label for="id_q1">The first question:</label>
            <input type="text" name="q1" id="id_q1" required></p>
            <p><label for="id_q2">What is your name?</label>
            <input type="text" name="q2" id="id_q2" required></p>
            <p><label for="id_q3">The answer to life is:</label>
            <input type="text" name="q3" id="id_q3" required></p>
            <p><label for="id_q4">Answer this question!</label>
            <input type="text" name="q4" id="id_q4" required></p>
            <p><label for="id_q5">The last question. Period.</label>
            <input type="text" name="q5" id="id_q5" required></p>
            """,
        )

        # If a label is set to the empty string for a field, that field won't
        # get a label.
        class UserRegistration(Form):
            username = CharField(max_length=10, label="")
            password = CharField(widget=PasswordInput)

        p = UserRegistration(auto_id=False)
        self.assertHTMLEqual(
            p.as_ul(),
            """<li> <input type="text" name="username" maxlength="10" required></li>
<li>Password: <input type="password" name="password" required></li>""",
        )
        p = UserRegistration(auto_id="id_%s")
        self.assertHTMLEqual(
            p.as_ul(),
            """
            <li>
            <input id="id_username" type="text" name="username" maxlength="10" required>
            </li>
            <li><label for="id_password">Password:</label>
            <input type="password" name="password" id="id_password" required></li>
            """,
        )

        # If label is None, Django will auto-create the label from the field
        # name. This is default behavior.
        class UserRegistration(Form):
            username = CharField(max_length=10, label=None)
            password = CharField(widget=PasswordInput)

        p = UserRegistration(auto_id=False)
        self.assertHTMLEqual(
            p.as_ul(),
            '<li>Username: <input type="text" name="username" maxlength="10" required>'
            "</li>"
            '<li>Password: <input type="password" name="password" required></li>',
        )
        p = UserRegistration(auto_id="id_%s")
        self.assertHTMLEqual(
            p.as_ul(),
            """<li><label for="id_username">Username:</label>
<input id="id_username" type="text" name="username" maxlength="10" required></li>
<li><label for="id_password">Password:</label>
<input type="password" name="password" id="id_password" required></li>""",
        )

    def test_label_suffix(self):
        # You can specify the 'label_suffix' argument to a Form class to modify
        # the punctuation symbol used at the end of a label. By default, the
        # colon (:) is used, and is only appended to the label if the label
        # doesn't already end with a punctuation symbol: ., !, ? or :. If you
        # specify a different suffix, it will be appended regardless of the
        # last character of the label.
        class FavoriteForm(Form):
            color = CharField(label="Favorite color?")
            animal = CharField(label="Favorite animal")
            answer = CharField(label="Secret answer", label_suffix=" =")

        f = FavoriteForm(auto_id=False)
        self.assertHTMLEqual(
            f.as_ul(),
            """<li>Favorite color? <input type="text" name="color" required></li>
<li>Favorite animal: <input type="text" name="animal" required></li>
<li>Secret answer = <input type="text" name="answer" required></li>""",
        )

        f = FavoriteForm(auto_id=False, label_suffix="?")
        self.assertHTMLEqual(
            f.as_ul(),
            """<li>Favorite color? <input type="text" name="color" required></li>
<li>Favorite animal? <input type="text" name="animal" required></li>
<li>Secret answer = <input type="text" name="answer" required></li>""",
        )

        f = FavoriteForm(auto_id=False, label_suffix="")
        self.assertHTMLEqual(
            f.as_ul(),
            """<li>Favorite color? <input type="text" name="color" required></li>
<li>Favorite animal <input type="text" name="animal" required></li>
<li>Secret answer = <input type="text" name="answer" required></li>""",
        )

        f = FavoriteForm(auto_id=False, label_suffix="\u2192")
        self.assertHTMLEqual(
            f.as_ul(),
            '<li>Favorite color? <input type="text" name="color" required></li>\n'
            "<li>Favorite animal\u2192 "
            '<input type="text" name="animal" required></li>\n'
            '<li>Secret answer = <input type="text" name="answer" required></li>',
        )

    def test_initial_data(self):
        # You can specify initial data for a field by using the 'initial'
        # argument to a Field class. This initial data is displayed when a Form
        # is rendered with *no* data. It is not displayed when a Form is
        # rendered with any data (including an empty dictionary). Also, the
        # initial value is *not* used if data for a particular required field
        # isn't provided.
        class UserRegistration(Form):
            username = CharField(max_length=10, initial="django")
            password = CharField(widget=PasswordInput)

        # Here, we're not submitting any data, so the initial value will be
        # displayed.)
        p = UserRegistration(auto_id=False)
        self.assertHTMLEqual(
            p.as_ul(),
            """
            <li>Username: <input type="text" name="username" value="django"
                maxlength="10" required></li>
            <li>Password: <input type="password" name="password" required></li>
            """,
        )

        # Here, we're submitting data, so the initial value will *not* be
        # displayed.
        p = UserRegistration({}, auto_id=False)
        self.assertHTMLEqual(
            p.as_ul(),
            """<li><ul class="errorlist"><li>This field is required.</li></ul>
Username: <input type="text" name="username" maxlength="10" aria-invalid="true"
required></li><li><ul class="errorlist"><li>This field is required.</li></ul>
Password: <input type="password" name="password" aria-invalid="true" required></li>""",
        )
        p = UserRegistration({"username": ""}, auto_id=False)
        self.assertHTMLEqual(
            p.as_ul(),
            """<li><ul class="errorlist"><li>This field is required.</li></ul>
Username: <input type="text" name="username" maxlength="10" aria-invalid="true"
required></li><li><ul class="errorlist"><li>This field is required.</li></ul>
Password: <input type="password" name="password" aria-invalid="true" required></li>""",
        )
        p = UserRegistration({"username": "foo"}, auto_id=False)
        self.assertHTMLEqual(
            p.as_ul(),
            """
            <li>Username: <input type="text" name="username" value="foo" maxlength="10"
                required></li>
            <li><ul class="errorlist"><li>This field is required.</li></ul>
            Password: <input type="password" name="password" aria-invalid="true"
            required></li>
            """,
        )

        # An 'initial' value is *not* used as a fallback if data is not
        # provided. In this example, we don't provide a value for 'username',
        # and the form raises a validation error rather than using the initial
        # value for 'username'.
        p = UserRegistration({"password": "secret"})
        self.assertEqual(p.errors["username"], ["This field is required."])
        self.assertFalse(p.is_valid())

    def test_dynamic_initial_data(self):
        # The previous technique dealt with "hard-coded" initial data, but it's
        # also possible to specify initial data after you've already created
        # the Form class (i.e., at runtime). Use the 'initial' parameter to the
        # Form constructor. This should be a dictionary containing initial
        # values for one or more fields in the form, keyed by field name.
        class UserRegistration(Form):
            username = CharField(max_length=10)
            password = CharField(widget=PasswordInput)

        # Here, we're not submitting any data, so the initial value will be
        # displayed.)
        p = UserRegistration(initial={"username": "django"}, auto_id=False)
        self.assertHTMLEqual(
            p.as_ul(),
            """
            <li>Username: <input type="text" name="username" value="django"
                maxlength="10" required></li>
            <li>Password: <input type="password" name="password" required></li>
            """,
        )
        p = UserRegistration(initial={"username": "stephane"}, auto_id=False)
        self.assertHTMLEqual(
            p.as_ul(),
            """
            <li>Username: <input type="text" name="username" value="stephane"
                maxlength="10" required></li>
            <li>Password: <input type="password" name="password" required></li>
            """,
        )

        # The 'initial' parameter is meaningless if you pass data.
        p = UserRegistration({}, initial={"username": "django"}, auto_id=False)
        self.assertHTMLEqual(
            p.as_ul(),
            """<li><ul class="errorlist"><li>This field is required.</li></ul>
Username: <input type="text" name="username" maxlength="10" aria-invalid="true"
required></li><li><ul class="errorlist"><li>This field is required.</li></ul>
Password: <input type="password" name="password" aria-invalid="true" required></li>""",
        )
        p = UserRegistration(
            {"username": ""}, initial={"username": "django"}, auto_id=False
        )
        self.assertHTMLEqual(
            p.as_ul(),
            """<li><ul class="errorlist"><li>This field is required.</li></ul>
Username: <input type="text" name="username" maxlength="10" aria-invalid="true"
required></li><li><ul class="errorlist"><li>This field is required.</li></ul>
Password: <input type="password" name="password" aria-invalid="true" required></li>""",
        )
        p = UserRegistration(
            {"username": "foo"}, initial={"username": "django"}, auto_id=False
        )
        self.assertHTMLEqual(
            p.as_ul(),
            """
            <li>Username: <input type="text" name="username" value="foo" maxlength="10"
                required></li>
            <li><ul class="errorlist"><li>This field is required.</li></ul>
            Password: <input type="password" name="password" aria-invalid="true"
            required></li>
            """,
        )

        # A dynamic 'initial' value is *not* used as a fallback if data is not
        # provided. In this example, we don't provide a value for 'username',
        # and the form raises a validation error rather than using the initial
        # value for 'username'.
        p = UserRegistration({"password": "secret"}, initial={"username": "django"})
        self.assertEqual(p.errors["username"], ["This field is required."])
        self.assertFalse(p.is_valid())

        # If a Form defines 'initial' *and* 'initial' is passed as a parameter
        # to Form(), then the latter will get precedence.
        class UserRegistration(Form):
            username = CharField(max_length=10, initial="django")
            password = CharField(widget=PasswordInput)

        p = UserRegistration(initial={"username": "babik"}, auto_id=False)
        self.assertHTMLEqual(
            p.as_ul(),
            """
            <li>Username: <input type="text" name="username" value="babik"
                maxlength="10" required></li>
            <li>Password: <input type="password" name="password" required></li>
            """,
        )

    def test_callable_initial_data(self):
        # The previous technique dealt with raw values as initial data, but
        # it's also possible to specify callable data.
        class UserRegistration(Form):
            username = CharField(max_length=10)
            password = CharField(widget=PasswordInput)
            options = MultipleChoiceField(
                choices=[("f", "foo"), ("b", "bar"), ("w", "whiz")]
            )

        # We need to define functions that get called later.)
        def initial_django():
            return "django"

        def initial_stephane():
            return "stephane"

        def initial_options():
            return ["f", "b"]

        def initial_other_options():
            return ["b", "w"]

        # Here, we're not submitting any data, so the initial value will be
        # displayed.)
        p = UserRegistration(
            initial={"username": initial_django, "options": initial_options},
            auto_id=False,
        )
        self.assertHTMLEqual(
            p.as_ul(),
            """
            <li>Username: <input type="text" name="username" value="django"
                maxlength="10" required></li>
            <li>Password: <input type="password" name="password" required></li>
            <li>Options: <select multiple name="options" required>
            <option value="f" selected>foo</option>
            <option value="b" selected>bar</option>
            <option value="w">whiz</option>
            </select></li>
            """,
        )

        # The 'initial' parameter is meaningless if you pass data.
        p = UserRegistration(
            {},
            initial={"username": initial_django, "options": initial_options},
            auto_id=False,
        )
        self.assertHTMLEqual(
            p.as_ul(),
            """<li><ul class="errorlist"><li>This field is required.</li></ul>
Username: <input type="text" name="username" maxlength="10" aria-invalid="true"
required></li><li><ul class="errorlist"><li>This field is required.</li></ul>
Password: <input type="password" name="password" aria-invalid="true"
required></li><li><ul class="errorlist"><li>This field is required.</li></ul>
Options: <select multiple name="options" aria-invalid="true" required>
<option value="f">foo</option>
<option value="b">bar</option>
<option value="w">whiz</option>
</select></li>""",
        )
        p = UserRegistration(
            {"username": ""}, initial={"username": initial_django}, auto_id=False
        )
        self.assertHTMLEqual(
            p.as_ul(),
            """<li><ul class="errorlist"><li>This field is required.</li></ul>
Username: <input type="text" name="username" maxlength="10" aria-invalid="true"
required></li><li><ul class="errorlist"><li>This field is required.</li></ul>
Password: <input type="password" name="password" aria-invalid="true" required></li>
<li><ul class="errorlist"><li>This field is required.</li></ul>
Options: <select multiple name="options" aria-invalid="true" required>
<option value="f">foo</option>
<option value="b">bar</option>
<option value="w">whiz</option>
</select></li>""",
        )
        p = UserRegistration(
            {"username": "foo", "options": ["f", "b"]},
            initial={"username": initial_django},
            auto_id=False,
        )
        self.assertHTMLEqual(
            p.as_ul(),
            """
            <li>Username: <input type="text" name="username" value="foo" maxlength="10"
                required></li>
            <li><ul class="errorlist"><li>This field is required.</li></ul>
            Password: <input type="password" name="password" aria-invalid="true"
            required></li><li>Options: <select multiple name="options" required>
            <option value="f" selected>foo</option>
            <option value="b" selected>bar</option>
            <option value="w">whiz</option>
            </select></li>
            """,
        )

        # A callable 'initial' value is *not* used as a fallback if data is not
        # provided. In this example, we don't provide a value for 'username',
        # and the form raises a validation error rather than using the initial
        # value for 'username'.
        p = UserRegistration(
            {"password": "secret"},
            initial={"username": initial_django, "options": initial_options},
        )
        self.assertEqual(p.errors["username"], ["This field is required."])
        self.assertFalse(p.is_valid())

        # If a Form defines 'initial' *and* 'initial' is passed as a parameter
        # to Form(), then the latter will get precedence.
        class UserRegistration(Form):
            username = CharField(max_length=10, initial=initial_django)
            password = CharField(widget=PasswordInput)
            options = MultipleChoiceField(
                choices=[("f", "foo"), ("b", "bar"), ("w", "whiz")],
                initial=initial_other_options,
            )

        p = UserRegistration(auto_id=False)
        self.assertHTMLEqual(
            p.as_ul(),
            """
            <li>Username: <input type="text" name="username" value="django"
                maxlength="10" required></li>
            <li>Password: <input type="password" name="password" required></li>
            <li>Options: <select multiple name="options" required>
            <option value="f">foo</option>
            <option value="b" selected>bar</option>
            <option value="w" selected>whiz</option>
            </select></li>
            """,
        )
        p = UserRegistration(
            initial={"username": initial_stephane, "options": initial_options},
            auto_id=False,
        )
        self.assertHTMLEqual(
            p.as_ul(),
            """
            <li>Username: <input type="text" name="username" value="stephane"
                maxlength="10" required></li>
            <li>Password: <input type="password" name="password" required></li>
            <li>Options: <select multiple name="options" required>
            <option value="f" selected>foo</option>
            <option value="b" selected>bar</option>
            <option value="w">whiz</option>
            </select></li>
            """,
        )

    def test_get_initial_for_field(self):
        now = datetime.datetime(2006, 10, 25, 14, 30, 45, 123456)

        class PersonForm(Form):
            first_name = CharField(initial="John")
            last_name = CharField(initial="Doe")
            age = IntegerField()
            occupation = CharField(initial=lambda: "Unknown")
            dt_fixed = DateTimeField(initial=now)
            dt_callable = DateTimeField(initial=lambda: now)

        form = PersonForm(initial={"first_name": "Jane"})
        cases = [
            ("age", None),
            ("last_name", "Doe"),
            # Form.initial overrides Field.initial.
            ("first_name", "Jane"),
            # Callables are evaluated.
            ("occupation", "Unknown"),
            # Microseconds are removed from datetimes.
            ("dt_fixed", datetime.datetime(2006, 10, 25, 14, 30, 45)),
            ("dt_callable", datetime.datetime(2006, 10, 25, 14, 30, 45)),
        ]
        for field_name, expected in cases:
            with self.subTest(field_name=field_name):
                field = form.fields[field_name]
                actual = form.get_initial_for_field(field, field_name)
                self.assertEqual(actual, expected)

    def test_changed_data(self):
        class Person(Form):
            first_name = CharField(initial="Hans")
            last_name = CharField(initial="Greatel")
            birthday = DateField(initial=datetime.date(1974, 8, 16))

        p = Person(
            data={"first_name": "Hans", "last_name": "Scrmbl", "birthday": "1974-08-16"}
        )
        self.assertTrue(p.is_valid())
        self.assertNotIn("first_name", p.changed_data)
        self.assertIn("last_name", p.changed_data)
        self.assertNotIn("birthday", p.changed_data)

        # A field raising ValidationError is always in changed_data
        class PedanticField(Field):
            def to_python(self, value):
                raise ValidationError("Whatever")

        class Person2(Person):
            pedantic = PedanticField(initial="whatever", show_hidden_initial=True)

        p = Person2(
            data={
                "first_name": "Hans",
                "last_name": "Scrmbl",
                "birthday": "1974-08-16",
                "initial-pedantic": "whatever",
            }
        )
        self.assertFalse(p.is_valid())
        self.assertIn("pedantic", p.changed_data)

    def test_boundfield_values(self):
        # It's possible to get to the value which would be used for rendering
        # the widget for a field by using the BoundField's value method.

        class UserRegistration(Form):
            username = CharField(max_length=10, initial="djangonaut")
            password = CharField(widget=PasswordInput)

        unbound = UserRegistration()
        bound = UserRegistration({"password": "foo"})
        self.assertIsNone(bound["username"].value())
        self.assertEqual(unbound["username"].value(), "djangonaut")
        self.assertEqual(bound["password"].value(), "foo")
        self.assertIsNone(unbound["password"].value())

    def test_boundfield_initial_called_once(self):
        """
        Multiple calls to BoundField().value() in an unbound form should return
        the same result each time (#24391).
        """

        class MyForm(Form):
            name = CharField(max_length=10, initial=uuid.uuid4)

        form = MyForm()
        name = form["name"]
        self.assertEqual(name.value(), name.value())
        # BoundField is also cached
        self.assertIs(form["name"], name)

    def test_boundfield_value_disabled_callable_initial(self):
        class PersonForm(Form):
            name = CharField(initial=lambda: "John Doe", disabled=True)

        # Without form data.
        form = PersonForm()
        self.assertEqual(form["name"].value(), "John Doe")

        # With form data. As the field is disabled, the value should not be
        # affected by the form data.
        form = PersonForm({})
        self.assertEqual(form["name"].value(), "John Doe")

    def test_custom_boundfield(self):
        class CustomField(CharField):
            def get_bound_field(self, form, name):
                return (form, name)

        class SampleForm(Form):
            name = CustomField()

        f = SampleForm()
        self.assertEqual(f["name"], (f, "name"))

    def test_initial_datetime_values(self):
        now = datetime.datetime.now()
        # Nix microseconds (since they should be ignored). #22502
        now_no_ms = now.replace(microsecond=0)
        if now == now_no_ms:
            now = now.replace(microsecond=1)

        def delayed_now():
            return now

        def delayed_now_time():
            return now.time()

        class HiddenInputWithoutMicrosec(HiddenInput):
            supports_microseconds = False

        class TextInputWithoutMicrosec(TextInput):
            supports_microseconds = False

        class DateTimeForm(Form):
            # Test a non-callable.
            fixed = DateTimeField(initial=now)
            auto_timestamp = DateTimeField(initial=delayed_now)
            auto_time_only = TimeField(initial=delayed_now_time)
            supports_microseconds = DateTimeField(initial=delayed_now, widget=TextInput)
            hi_default_microsec = DateTimeField(initial=delayed_now, widget=HiddenInput)
            hi_without_microsec = DateTimeField(
                initial=delayed_now, widget=HiddenInputWithoutMicrosec
            )
            ti_without_microsec = DateTimeField(
                initial=delayed_now, widget=TextInputWithoutMicrosec
            )

        unbound = DateTimeForm()
        cases = [
            ("fixed", now_no_ms),
            ("auto_timestamp", now_no_ms),
            ("auto_time_only", now_no_ms.time()),
            ("supports_microseconds", now),
            ("hi_default_microsec", now),
            ("hi_without_microsec", now_no_ms),
            ("ti_without_microsec", now_no_ms),
        ]
        for field_name, expected in cases:
            with self.subTest(field_name=field_name):
                actual = unbound[field_name].value()
                self.assertEqual(actual, expected)
                # Also check get_initial_for_field().
                field = unbound.fields[field_name]
                actual = unbound.get_initial_for_field(field, field_name)
                self.assertEqual(actual, expected)

    def get_datetime_form_with_callable_initial(self, disabled, microseconds=0):
        class FakeTime:
            def __init__(self):
                self.elapsed_seconds = 0

            def now(self):
                self.elapsed_seconds += 1
                return datetime.datetime(
                    2006,
                    10,
                    25,
                    14,
                    30,
                    45 + self.elapsed_seconds,
                    microseconds,
                )

        class DateTimeForm(Form):
            dt = DateTimeField(initial=FakeTime().now, disabled=disabled)

        return DateTimeForm({})

    def test_datetime_clean_disabled_callable_initial_microseconds(self):
        """
        Cleaning a form with a disabled DateTimeField and callable initial
        removes microseconds.
        """
        form = self.get_datetime_form_with_callable_initial(
            disabled=True,
            microseconds=123456,
        )
        self.assertEqual(form.errors, {})
        self.assertEqual(
            form.cleaned_data,
            {
                "dt": datetime.datetime(2006, 10, 25, 14, 30, 46),
            },
        )

    def test_datetime_clean_disabled_callable_initial_bound_field(self):
        """
        The cleaned value for a form with a disabled DateTimeField and callable
        initial matches the bound field's cached initial value.
        """
        form = self.get_datetime_form_with_callable_initial(disabled=True)
        self.assertEqual(form.errors, {})
        cleaned = form.cleaned_data["dt"]
        self.assertEqual(cleaned, datetime.datetime(2006, 10, 25, 14, 30, 46))
        bf = form["dt"]
        self.assertEqual(cleaned, bf.initial)

    def test_datetime_changed_data_callable_with_microseconds(self):
        class DateTimeForm(Form):
            dt = DateTimeField(
                initial=lambda: datetime.datetime(2006, 10, 25, 14, 30, 45, 123456),
                disabled=True,
            )

        form = DateTimeForm({"dt": "2006-10-25 14:30:45"})
        self.assertEqual(form.changed_data, [])

    def test_help_text(self):
        # You can specify descriptive text for a field by using the 'help_text'
        # argument.
        class UserRegistration(Form):
            username = CharField(max_length=10, help_text="e.g., user@example.com")
            password = CharField(
                widget=PasswordInput, help_text="Wählen Sie mit Bedacht."
            )

        p = UserRegistration(auto_id=False)
        self.assertHTMLEqual(
            p.as_ul(),
            """<li>Username: <input type="text" name="username" maxlength="10" required>
<span class="helptext">e.g., user@example.com</span></li>
<li>Password: <input type="password" name="password" required>
<span class="helptext">Wählen Sie mit Bedacht.</span></li>""",
        )
        self.assertHTMLEqual(
            p.as_p(),
            """<p>Username: <input type="text" name="username" maxlength="10" required>
<span class="helptext">e.g., user@example.com</span></p>
<p>Password: <input type="password" name="password" required>
<span class="helptext">Wählen Sie mit Bedacht.</span></p>""",
        )
        self.assertHTMLEqual(
            p.as_table(),
            """
            <tr><th>Username:</th><td>
            <input type="text" name="username" maxlength="10" required><br>
            <span class="helptext">e.g., user@example.com</span></td></tr>
            <tr><th>Password:</th><td><input type="password" name="password" required>
            <br>
            <span class="helptext">Wählen Sie mit Bedacht.</span></td></tr>""",
        )
        self.assertHTMLEqual(
            p.as_div(),
            '<div>Username: <div class="helptext">e.g., user@example.com</div>'
            '<input type="text" name="username" maxlength="10" required></div>'
            '<div>Password: <div class="helptext">Wählen Sie mit Bedacht.</div>'
            '<input type="password" name="password" required></div>',
        )

        # The help text is displayed whether or not data is provided for the
        # form.
        p = UserRegistration({"username": "foo"}, auto_id=False)
        self.assertHTMLEqual(
            p.as_ul(),
            '<li>Username: <input type="text" name="username" value="foo" '
            'maxlength="10" required>'
            '<span class="helptext">e.g., user@example.com</span></li>'
            '<li><ul class="errorlist"><li>This field is required.</li></ul>'
            'Password: <input type="password" name="password" aria-invalid="true" '
            'required><span class="helptext">Wählen Sie mit Bedacht.</span></li>',
        )

        # help_text is not displayed for hidden fields. It can be used for
        # documentation purposes, though.
        class UserRegistration(Form):
            username = CharField(max_length=10, help_text="e.g., user@example.com")
            password = CharField(widget=PasswordInput)
            next = CharField(
                widget=HiddenInput, initial="/", help_text="Redirect destination"
            )

        p = UserRegistration(auto_id=False)
        self.assertHTMLEqual(
            p.as_ul(),
            """<li>Username: <input type="text" name="username" maxlength="10" required>
<span class="helptext">e.g., user@example.com</span></li>
<li>Password: <input type="password" name="password" required>
<input type="hidden" name="next" value="/"></li>""",
        )

    def test_help_text_html_safe(self):
        """help_text should not be escaped."""

        class UserRegistration(Form):
            username = CharField(max_length=10, help_text="e.g., user@example.com")
            password = CharField(
                widget=PasswordInput,
                help_text="Help text is <strong>escaped</strong>.",
            )

        p = UserRegistration(auto_id=False)
        self.assertHTMLEqual(
            p.as_ul(),
            '<li>Username: <input type="text" name="username" maxlength="10" required>'
            '<span class="helptext">e.g., user@example.com</span></li>'
            '<li>Password: <input type="password" name="password" required>'
            '<span class="helptext">Help text is <strong>escaped</strong>.</span></li>',
        )
        self.assertHTMLEqual(
            p.as_p(),
            '<p>Username: <input type="text" name="username" maxlength="10" required>'
            '<span class="helptext">e.g., user@example.com</span></p>'
            '<p>Password: <input type="password" name="password" required>'
            '<span class="helptext">Help text is <strong>escaped</strong>.</span></p>',
        )
        self.assertHTMLEqual(
            p.as_table(),
            "<tr><th>Username:</th><td>"
            '<input type="text" name="username" maxlength="10" required><br>'
            '<span class="helptext">e.g., user@example.com</span></td></tr>'
            "<tr><th>Password:</th><td>"
            '<input type="password" name="password" required><br>'
            '<span class="helptext">Help text is <strong>escaped</strong>.</span>'
            "</td></tr>",
        )

    def test_widget_attrs_custom_aria_describedby(self):
        # aria-describedby provided to the widget overrides the default.

        class UserRegistration(Form):
            username = CharField(
                max_length=255,
                help_text="e.g., user@example.com",
                widget=TextInput(attrs={"aria-describedby": "custom-description"}),
            )
            password = CharField(
                widget=PasswordInput, help_text="Wählen Sie mit Bedacht."
            )

        p = UserRegistration()
        self.assertHTMLEqual(
            p.as_div(),
            '<div><label for="id_username">Username:</label>'
            '<div class="helptext" id="id_username_helptext">e.g., user@example.com'
            '</div><input type="text" name="username" maxlength="255" required '
            'aria-describedby="custom-description" id="id_username">'
            "</div><div>"
            '<label for="id_password">Password:</label>'
            '<div class="helptext" id="id_password_helptext">Wählen Sie mit Bedacht.'
            '</div><input type="password" name="password" required '
            'aria-describedby="id_password_helptext" id="id_password"></div>',
        )
        self.assertHTMLEqual(
            p.as_ul(),
            '<li><label for="id_username">Username:</label><input type="text" '
            'name="username" maxlength="255" required '
            'aria-describedby="custom-description" id="id_username">'
            '<span class="helptext" id="id_username_helptext">e.g., user@example.com'
            "</span></li><li>"
            '<label for="id_password">Password:</label>'
            '<input type="password" name="password" required '
            'aria-describedby="id_password_helptext" id="id_password">'
            '<span class="helptext" id="id_password_helptext">Wählen Sie mit Bedacht.'
            "</span></li>",
        )
        self.assertHTMLEqual(
            p.as_p(),
            '<p><label for="id_username">Username:</label><input type="text" '
            'name="username" maxlength="255" required '
            'aria-describedby="custom-description" id="id_username">'
            '<span class="helptext" id="id_username_helptext">e.g., user@example.com'
            "</span></p><p>"
            '<label for="id_password">Password:</label>'
            '<input type="password" name="password" required '
            'aria-describedby="id_password_helptext" id="id_password">'
            '<span class="helptext" id="id_password_helptext">Wählen Sie mit Bedacht.'
            "</span></p>",
        )
        self.assertHTMLEqual(
            p.as_table(),
            '<tr><th><label for="id_username">Username:</label></th><td>'
            '<input type="text" name="username" maxlength="255" required '
            'aria-describedby="custom-description" id="id_username"><br>'
            '<span class="helptext" id="id_username_helptext">e.g., user@example.com'
            "</span></td></tr><tr><th>"
            '<label for="id_password">Password:</label></th><td>'
            '<input type="password" name="password" required '
            'aria-describedby="id_password_helptext" id="id_password"><br>'
            '<span class="helptext" id="id_password_helptext">Wählen Sie mit Bedacht.'
            "</span></td></tr>",
        )

    def test_aria_describedby_custom_widget_id(self):
        class UserRegistration(Form):
            username = CharField(
                max_length=255,
                help_text="e.g., user@example.com",
                widget=TextInput(attrs={"id": "custom-id"}),
            )

        f = UserRegistration()
        self.assertHTMLEqual(
            str(f),
            '<div><label for="custom-id">Username:</label>'
            '<div class="helptext" id="id_username_helptext">e.g., user@example.com'
            '</div><input type="text" name="username" id="custom-id" maxlength="255" '
            'required aria-describedby="id_username_helptext"></div>',
        )

    def test_select_aria_describedby(self):
        class TestForm(Form):
            color = MultipleChoiceField(
                choices=[("red", "Red"), ("green", "Green")],
                help_text="Select Color",
            )

        f = TestForm({"color": "Blue"})
        self.assertHTMLEqual(
            str(f),
            '<div><label for="id_color">Color:</label><div class="helptext" '
            'id="id_color_helptext">Select Color</div>'
            '<ul class="errorlist" id="id_color_error"><li>Enter a list of values.'
            '</li></ul><select name="color" required aria-invalid="true" '
            'aria-describedby="id_color_helptext id_color_error" id="id_color" '
            'multiple><option value="red">Red</option>'
            '<option value="green">Green</option></select></div>',
        )

    def test_textarea_aria_describedby(self):
        class TestForm(Form):
            color = CharField(widget=Textarea, max_length=5, help_text="Enter Color")

        f = TestForm({"color": "Purple"})
        self.assertHTMLEqual(
            str(f),
            '<div><label for="id_color">Color:</label>'
            '<div class="helptext" id="id_color_helptext">Enter Color</div>'
            '<ul class="errorlist" id="id_color_error">'
            "<li>Ensure this value has at most 5 characters (it has 6).</li></ul>"
            '<textarea name="color" cols="40" rows="10" maxlength="5" required '
            'aria-invalid="true" aria-describedby="id_color_helptext id_color_error" '
            'id="id_color">Purple</textarea></div>',
        )

    def test_aria_describedby_called_multiple_times(self):
        class TestForm(Form):
            color = CharField(widget=Textarea, help_text="Enter Color")

        f = TestForm({"color": "Purple"})
        self.assertEqual(f["color"].aria_describedby, "id_color_helptext")
        f.add_error("color", "An error about Purple.")
        self.assertEqual(
            f["color"].aria_describedby, "id_color_helptext id_color_error"
        )

    def test_fieldset_aria_describedby(self):
        class FieldsetForm(Form):
            checkbox = MultipleChoiceField(
                choices=[("a", "A"), ("b", "B")],
                widget=CheckboxSelectMultiple,
                help_text="Checkbox help text",
            )
            radio = MultipleChoiceField(
                choices=[("a", "A"), ("b", "B")],
                widget=RadioSelect,
                help_text="Radio help text",
            )
            datetime = SplitDateTimeField(help_text="Enter Date and Time")

        f = FieldsetForm()
        self.assertHTMLEqual(
            str(f),
            '<div><fieldset aria-describedby="id_checkbox_helptext">'
            "<legend>Checkbox:</legend>"
            '<div class="helptext" id="id_checkbox_helptext">Checkbox help text</div>'
            '<div id="id_checkbox"><div>'
            '<label for="id_checkbox_0"><input type="checkbox" name="checkbox" '
            'value="a" id="id_checkbox_0" /> A</label>'
            "</div><div>"
            '<label for="id_checkbox_1"><input type="checkbox" name="checkbox" '
            'value="b" id="id_checkbox_1" /> B</label>'
            "</div></div></fieldset></div>"
            '<div><fieldset aria-describedby="id_radio_helptext">'
            "<legend>Radio:</legend>"
            '<div class="helptext" id="id_radio_helptext">Radio help text</div>'
            '<div id="id_radio"><div>'
            '<label for="id_radio_0"><input type="radio" name="radio" value="a" '
            'required id="id_radio_0" />A</label>'
            "</div><div>"
            '<label for="id_radio_1"><input type="radio" name="radio" value="b" '
            'required id="id_radio_1" /> B</label>'
            "</div></div></fieldset></div>"
            '<div><fieldset aria-describedby="id_datetime_helptext">'
            "<legend>Datetime:</legend>"
            '<div class="helptext" id="id_datetime_helptext">Enter Date and Time</div>'
            '<input type="text" name="datetime_0" required id="id_datetime_0" />'
            '<input type="text" name="datetime_1" required id="id_datetime_1" />'
            "</fieldset></div>",
        )
        f = FieldsetForm({})
        self.assertHTMLEqual(
            '<div><fieldset aria-describedby="id_checkbox_helptext '
            'id_checkbox_error"> <legend>Checkbox:</legend> <div class="helptext" '
            'id="id_checkbox_helptext">Checkbox help text</div> <ul class="errorlist" '
            'id="id_checkbox_error"> <li>This field is required.</li> </ul> '
            '<div id="id_checkbox"> <div> <label for="id_checkbox_0"><input '
            'type="checkbox" name="checkbox" value="a" aria-invalid="true" '
            'id="id_checkbox_0" /> A</label> </div> <div> <label for="id_checkbox_1">'
            '<input type="checkbox" name="checkbox" value="b" aria-invalid="true" '
            'id="id_checkbox_1" /> B</label> </div> </div> </fieldset> </div> <div> '
            '<fieldset aria-describedby="id_radio_helptext id_radio_error"> '
            '<legend>Radio:</legend> <div class="helptext" id="id_radio_helptext">'
            'Radio help text</div> <ul class="errorlist" id="id_radio_error"><li>'
            'This field is required.</li> </ul> <div id="id_radio"><div><label '
            'for="id_radio_0"><input type="radio" name="radio" value="a" required '
            'aria-invalid="true" id="id_radio_0" />A</label></div><div><label '
            'for="id_radio_1"><input type="radio" name="radio" value="b" required '
            'aria-invalid="true" id="id_radio_1" />B</label></div></div></fieldset>'
            '</div><div><fieldset aria-describedby="id_datetime_helptext '
            'id_datetime_error"><legend>Datetime:</legend><div class="helptext" '
            'id="id_datetime_helptext">Enter Date and Time</div><ul class="errorlist" '
            'id="id_datetime_error"><li>This field is required.</li></ul><input '
            'type="text" name="datetime_0" required aria-invalid="true" '
            'id="id_datetime_0" /><input type="text" name="datetime_1" required '
            'aria-invalid="true" id="id_datetime_1" /></fieldset></div>',
            str(f),
        )
        f = FieldsetForm(auto_id=False)
        # aria-describedby is not included.
        self.assertIn("<fieldset>", str(f))
        self.assertIn('<div class="helptext">', str(f))
        f = FieldsetForm(auto_id="custom_%s")
        # aria-describedby uses custom auto_id.
        self.assertIn('fieldset aria-describedby="custom_checkbox_helptext"', str(f))
        self.assertIn('<div class="helptext" id="custom_checkbox_helptext">', str(f))

    def test_fieldset_custom_aria_describedby(self):
        # aria-describedby set on widget results in aria-describedby being
        # added to widget and not the <fieldset>.
        class FieldsetForm(Form):
            checkbox = MultipleChoiceField(
                choices=[("a", "A"), ("b", "B")],
                widget=CheckboxSelectMultiple(attrs={"aria-describedby": "custom-id"}),
                help_text="Checkbox help text",
            )

        f = FieldsetForm()
        self.assertHTMLEqual(
            str(f),
            "<div><fieldset><legend>Checkbox:</legend>"
            '<div class="helptext" id="id_checkbox_helptext">Checkbox help text</div>'
            '<div id="id_checkbox"><div>'
            '<label for="id_checkbox_0"><input type="checkbox" name="checkbox" '
            'value="a" aria-describedby="custom-id" id="id_checkbox_0" />A</label>'
            "</div><div>"
            '<label for="id_checkbox_1"><input type="checkbox" name="checkbox" '
            'value="b" aria-describedby="custom-id" id="id_checkbox_1" />B</label>'
            "</div></div></fieldset></div>",
        )

    def test_as_widget_custom_aria_describedby(self):
        class FoodForm(Form):
            intl_name = CharField(help_text="The food's international name.")

        form = FoodForm({"intl_name": "Rendang"})
        self.assertHTMLEqual(
            form["intl_name"].as_widget(attrs={"aria-describedby": "some_custom_id"}),
            '<input type="text" name="intl_name" value="Rendang"'
            'aria-describedby="some_custom_id" required id="id_intl_name">',
        )

    def test_subclassing_forms(self):
        # You can subclass a Form to add fields. The resulting form subclass
        # will have all of the fields of the parent Form, plus whichever fields
        # you define in the subclass.
        class Person(Form):
            first_name = CharField()
            last_name = CharField()
            birthday = DateField()

        class Musician(Person):
            instrument = CharField()

        p = Person(auto_id=False)
        self.assertHTMLEqual(
            p.as_ul(),
            """<li>First name: <input type="text" name="first_name" required></li>
<li>Last name: <input type="text" name="last_name" required></li>
<li>Birthday: <input type="text" name="birthday" required></li>""",
        )
        m = Musician(auto_id=False)
        self.assertHTMLEqual(
            m.as_ul(),
            """<li>First name: <input type="text" name="first_name" required></li>
<li>Last name: <input type="text" name="last_name" required></li>
<li>Birthday: <input type="text" name="birthday" required></li>
<li>Instrument: <input type="text" name="instrument" required></li>""",
        )

        # Yes, you can subclass multiple forms. The fields are added in the
        # order in which the parent classes are listed.
        class Person(Form):
            first_name = CharField()
            last_name = CharField()
            birthday = DateField()

        class Instrument(Form):
            instrument = CharField()

        class Beatle(Person, Instrument):
            haircut_type = CharField()

        b = Beatle(auto_id=False)
        self.assertHTMLEqual(
            b.as_ul(),
            """<li>Instrument: <input type="text" name="instrument" required></li>
<li>First name: <input type="text" name="first_name" required></li>
<li>Last name: <input type="text" name="last_name" required></li>
<li>Birthday: <input type="text" name="birthday" required></li>
<li>Haircut type: <input type="text" name="haircut_type" required></li>""",
        )

    def test_forms_with_prefixes(self):
        # Sometimes it's necessary to have multiple forms display on the same
        # HTML page, or multiple copies of the same form. We can accomplish
        # this with form prefixes. Pass the keyword argument 'prefix' to the
        # Form constructor to use this feature. This value will be prepended to
        # each HTML form field name. One way to think about this is "namespaces
        # for HTML forms". Notice that in the data argument, each field's key
        # has the prefix, in this case 'person1', prepended to the actual field
        # name.
        class Person(Form):
            first_name = CharField()
            last_name = CharField()
            birthday = DateField()

        data = {
            "person1-first_name": "John",
            "person1-last_name": "Lennon",
            "person1-birthday": "1940-10-9",
        }
        p = Person(data, prefix="person1")
        self.assertHTMLEqual(
            p.as_ul(),
            """
            <li><label for="id_person1-first_name">First name:</label>
            <input type="text" name="person1-first_name" value="John"
                id="id_person1-first_name" required></li>
            <li><label for="id_person1-last_name">Last name:</label>
            <input type="text" name="person1-last_name" value="Lennon"
                id="id_person1-last_name" required></li>
            <li><label for="id_person1-birthday">Birthday:</label>
            <input type="text" name="person1-birthday" value="1940-10-9"
                id="id_person1-birthday" required></li>
            """,
        )
        self.assertHTMLEqual(
            str(p["first_name"]),
            '<input type="text" name="person1-first_name" value="John" '
            'id="id_person1-first_name" required>',
        )
        self.assertHTMLEqual(
            str(p["last_name"]),
            '<input type="text" name="person1-last_name" value="Lennon" '
            'id="id_person1-last_name" required>',
        )
        self.assertHTMLEqual(
            str(p["birthday"]),
            '<input type="text" name="person1-birthday" value="1940-10-9" '
            'id="id_person1-birthday" required>',
        )
        self.assertEqual(p.errors, {})
        self.assertTrue(p.is_valid())
        self.assertEqual(p.cleaned_data["first_name"], "John")
        self.assertEqual(p.cleaned_data["last_name"], "Lennon")
        self.assertEqual(p.cleaned_data["birthday"], datetime.date(1940, 10, 9))

        # Let's try submitting some bad data to make sure form.errors and
        # field.errors work as expected.
        data = {
            "person1-first_name": "",
            "person1-last_name": "",
            "person1-birthday": "",
        }
        p = Person(data, prefix="person1")
        self.assertEqual(p.errors["first_name"], ["This field is required."])
        self.assertEqual(p.errors["last_name"], ["This field is required."])
        self.assertEqual(p.errors["birthday"], ["This field is required."])
        self.assertEqual(p["first_name"].errors, ["This field is required."])
        # Accessing a nonexistent field.
        with self.assertRaises(KeyError):
            p["person1-first_name"].errors

        # In this example, the data doesn't have a prefix, but the form
        # requires it, so the form doesn't "see" the fields.
        data = {"first_name": "John", "last_name": "Lennon", "birthday": "1940-10-9"}
        p = Person(data, prefix="person1")
        self.assertEqual(p.errors["first_name"], ["This field is required."])
        self.assertEqual(p.errors["last_name"], ["This field is required."])
        self.assertEqual(p.errors["birthday"], ["This field is required."])

        # With prefixes, a single data dictionary can hold data for multiple
        # instances of the same form.
        data = {
            "person1-first_name": "John",
            "person1-last_name": "Lennon",
            "person1-birthday": "1940-10-9",
            "person2-first_name": "Jim",
            "person2-last_name": "Morrison",
            "person2-birthday": "1943-12-8",
        }
        p1 = Person(data, prefix="person1")
        self.assertTrue(p1.is_valid())
        self.assertEqual(p1.cleaned_data["first_name"], "John")
        self.assertEqual(p1.cleaned_data["last_name"], "Lennon")
        self.assertEqual(p1.cleaned_data["birthday"], datetime.date(1940, 10, 9))
        p2 = Person(data, prefix="person2")
        self.assertTrue(p2.is_valid())
        self.assertEqual(p2.cleaned_data["first_name"], "Jim")
        self.assertEqual(p2.cleaned_data["last_name"], "Morrison")
        self.assertEqual(p2.cleaned_data["birthday"], datetime.date(1943, 12, 8))

        # By default, forms append a hyphen between the prefix and the field
        # name, but a form can alter that behavior by implementing the
        # add_prefix() method. This method takes a field name and returns the
        # prefixed field, according to self.prefix.
        class Person(Form):
            first_name = CharField()
            last_name = CharField()
            birthday = DateField()

            def add_prefix(self, field_name):
                return (
                    "%s-prefix-%s" % (self.prefix, field_name)
                    if self.prefix
                    else field_name
                )

        p = Person(prefix="foo")
        self.assertHTMLEqual(
            p.as_ul(),
            """
            <li><label for="id_foo-prefix-first_name">First name:</label>
            <input type="text" name="foo-prefix-first_name"
                id="id_foo-prefix-first_name" required></li>
            <li><label for="id_foo-prefix-last_name">Last name:</label>
            <input type="text" name="foo-prefix-last_name" id="id_foo-prefix-last_name"
                required></li>
            <li><label for="id_foo-prefix-birthday">Birthday:</label>
            <input type="text" name="foo-prefix-birthday" id="id_foo-prefix-birthday"
                required></li>
            """,
        )
        data = {
            "foo-prefix-first_name": "John",
            "foo-prefix-last_name": "Lennon",
            "foo-prefix-birthday": "1940-10-9",
        }
        p = Person(data, prefix="foo")
        self.assertTrue(p.is_valid())
        self.assertEqual(p.cleaned_data["first_name"], "John")
        self.assertEqual(p.cleaned_data["last_name"], "Lennon")
        self.assertEqual(p.cleaned_data["birthday"], datetime.date(1940, 10, 9))

    def test_class_prefix(self):
        # Prefix can be also specified at the class level.
        class Person(Form):
            first_name = CharField()
            prefix = "foo"

        p = Person()
        self.assertEqual(p.prefix, "foo")

        p = Person(prefix="bar")
        self.assertEqual(p.prefix, "bar")

    def test_forms_with_null_boolean(self):
        # NullBooleanField is a bit of a special case because its presentation
        # (widget) is different than its data. This is handled transparently,
        # though.
        class Person(Form):
            name = CharField()
            is_cool = NullBooleanField()

        p = Person({"name": "Joe"}, auto_id=False)
        self.assertHTMLEqual(
            str(p["is_cool"]),
            """<select name="is_cool">
<option value="unknown" selected>Unknown</option>
<option value="true">Yes</option>
<option value="false">No</option>
</select>""",
        )
        p = Person({"name": "Joe", "is_cool": "1"}, auto_id=False)
        self.assertHTMLEqual(
            str(p["is_cool"]),
            """<select name="is_cool">
<option value="unknown" selected>Unknown</option>
<option value="true">Yes</option>
<option value="false">No</option>
</select>""",
        )
        p = Person({"name": "Joe", "is_cool": "2"}, auto_id=False)
        self.assertHTMLEqual(
            str(p["is_cool"]),
            """<select name="is_cool">
<option value="unknown">Unknown</option>
<option value="true" selected>Yes</option>
<option value="false">No</option>
</select>""",
        )
        p = Person({"name": "Joe", "is_cool": "3"}, auto_id=False)
        self.assertHTMLEqual(
            str(p["is_cool"]),
            """<select name="is_cool">
<option value="unknown">Unknown</option>
<option value="true">Yes</option>
<option value="false" selected>No</option>
</select>""",
        )
        p = Person({"name": "Joe", "is_cool": True}, auto_id=False)
        self.assertHTMLEqual(
            str(p["is_cool"]),
            """<select name="is_cool">
<option value="unknown">Unknown</option>
<option value="true" selected>Yes</option>
<option value="false">No</option>
</select>""",
        )
        p = Person({"name": "Joe", "is_cool": False}, auto_id=False)
        self.assertHTMLEqual(
            str(p["is_cool"]),
            """<select name="is_cool">
<option value="unknown">Unknown</option>
<option value="true">Yes</option>
<option value="false" selected>No</option>
</select>""",
        )
        p = Person({"name": "Joe", "is_cool": "unknown"}, auto_id=False)
        self.assertHTMLEqual(
            str(p["is_cool"]),
            """<select name="is_cool">
<option value="unknown" selected>Unknown</option>
<option value="true">Yes</option>
<option value="false">No</option>
</select>""",
        )
        p = Person({"name": "Joe", "is_cool": "true"}, auto_id=False)
        self.assertHTMLEqual(
            str(p["is_cool"]),
            """<select name="is_cool">
<option value="unknown">Unknown</option>
<option value="true" selected>Yes</option>
<option value="false">No</option>
</select>""",
        )
        p = Person({"name": "Joe", "is_cool": "false"}, auto_id=False)
        self.assertHTMLEqual(
            str(p["is_cool"]),
            """<select name="is_cool">
<option value="unknown">Unknown</option>
<option value="true">Yes</option>
<option value="false" selected>No</option>
</select>""",
        )

    def test_forms_with_file_fields(self):
        # FileFields are a special case because they take their data from the
        # request.FILES, not request.POST.
        class FileForm(Form):
            file1 = FileField()

        f = FileForm(auto_id=False)
        self.assertHTMLEqual(
            f.as_table(),
            "<tr><th>File1:</th><td>"
            '<input type="file" name="file1" required></td></tr>',
        )

        f = FileForm(data={}, files={}, auto_id=False)
        self.assertHTMLEqual(
            f.as_table(),
            "<tr><th>File1:</th><td>"
            '<ul class="errorlist"><li>This field is required.</li></ul>'
            '<input type="file" name="file1" aria-invalid="true" required></td></tr>',
        )

        f = FileForm(
            data={}, files={"file1": SimpleUploadedFile("name", b"")}, auto_id=False
        )
        self.assertHTMLEqual(
            f.as_table(),
            "<tr><th>File1:</th><td>"
            '<ul class="errorlist"><li>The submitted file is empty.</li></ul>'
            '<input type="file" name="file1" aria-invalid="true" required></td></tr>',
        )

        f = FileForm(
            data={}, files={"file1": "something that is not a file"}, auto_id=False
        )
        self.assertHTMLEqual(
            f.as_table(),
            "<tr><th>File1:</th><td>"
            '<ul class="errorlist"><li>No file was submitted. Check the '
            "encoding type on the form.</li></ul>"
            '<input type="file" name="file1" aria-invalid="true" required></td></tr>',
        )

        f = FileForm(
            data={},
            files={"file1": SimpleUploadedFile("name", b"some content")},
            auto_id=False,
        )
        self.assertHTMLEqual(
            f.as_table(),
            "<tr><th>File1:</th><td>"
            '<input type="file" name="file1" required></td></tr>',
        )
        self.assertTrue(f.is_valid())

        file1 = SimpleUploadedFile(
            "我隻氣墊船裝滿晒鱔.txt",
            "मेरी मँडराने वाली नाव सर्पमीनों से भरी ह".encode(),
        )
        f = FileForm(data={}, files={"file1": file1}, auto_id=False)
        self.assertHTMLEqual(
            f.as_table(),
            "<tr><th>File1:</th><td>"
            '<input type="file" name="file1" required></td></tr>',
        )

        # A required file field with initial data should not contain the
        # required HTML attribute. The file input is left blank by the user to
        # keep the existing, initial value.
        f = FileForm(initial={"file1": "resume.txt"}, auto_id=False)
        self.assertHTMLEqual(
            f.as_table(),
            '<tr><th>File1:</th><td><input type="file" name="file1"></td></tr>',
        )

    def test_filefield_initial_callable(self):
        class FileForm(Form):
            file1 = FileField(initial=lambda: "resume.txt")

        f = FileForm({})
        self.assertEqual(f.errors, {})
        self.assertEqual(f.cleaned_data["file1"], "resume.txt")

    def test_filefield_with_fileinput_required(self):
        class FileForm(Form):
            file1 = FileField(widget=FileInput)

        f = FileForm(auto_id=False)
        self.assertHTMLEqual(
            f.as_table(),
            "<tr><th>File1:</th><td>"
            '<input type="file" name="file1" required></td></tr>',
        )
        # A required file field with initial data doesn't contain the required
        # HTML attribute. The file input is left blank by the user to keep the
        # existing, initial value.
        f = FileForm(initial={"file1": "resume.txt"}, auto_id=False)
        self.assertHTMLEqual(
            f.as_table(),
            '<tr><th>File1:</th><td><input type="file" name="file1"></td></tr>',
        )

    def test_empty_permitted(self):
        # Sometimes (pretty much in formsets) we want to allow a form to pass
        # validation if it is completely empty. We can accomplish this by using
        # the empty_permitted argument to a form constructor.
        class SongForm(Form):
            artist = CharField()
            name = CharField()

        # First let's show what happens id empty_permitted=False (the default):
        data = {"artist": "", "song": ""}
        form = SongForm(data, empty_permitted=False)
        self.assertFalse(form.is_valid())
        self.assertEqual(
            form.errors,
            {
                "name": ["This field is required."],
                "artist": ["This field is required."],
            },
        )
        self.assertEqual(form.cleaned_data, {})

        # Now let's show what happens when empty_permitted=True and the form is
        # empty.
        form = SongForm(data, empty_permitted=True, use_required_attribute=False)
        self.assertTrue(form.is_valid())
        self.assertEqual(form.errors, {})
        self.assertEqual(form.cleaned_data, {})

        # But if we fill in data for one of the fields, the form is no longer
        # empty and the whole thing must pass validation.
        data = {"artist": "The Doors", "song": ""}
        form = SongForm(data, empty_permitted=False)
        self.assertFalse(form.is_valid())
        self.assertEqual(form.errors, {"name": ["This field is required."]})
        self.assertEqual(form.cleaned_data, {"artist": "The Doors"})

        # If a field is not given in the data then None is returned for its
        # data. Lets make sure that when checking for empty_permitted that None
        # is treated accordingly.
        data = {"artist": None, "song": ""}
        form = SongForm(data, empty_permitted=True, use_required_attribute=False)
        self.assertTrue(form.is_valid())

        # However, we *really* need to be sure we are checking for None as any
        # data in initial that returns False on a boolean call needs to be
        # treated literally.
        class PriceForm(Form):
            amount = FloatField()
            qty = IntegerField()

        data = {"amount": "0.0", "qty": ""}
        form = PriceForm(
            data,
            initial={"amount": 0.0},
            empty_permitted=True,
            use_required_attribute=False,
        )
        self.assertTrue(form.is_valid())

    def test_empty_permitted_and_use_required_attribute(self):
        msg = (
            "The empty_permitted and use_required_attribute arguments may not "
            "both be True."
        )
        with self.assertRaisesMessage(ValueError, msg):
            Person(empty_permitted=True, use_required_attribute=True)

    def test_extracting_hidden_and_visible(self):
        class SongForm(Form):
            token = CharField(widget=HiddenInput)
            artist = CharField()
            name = CharField()

        form = SongForm()
        self.assertEqual([f.name for f in form.hidden_fields()], ["token"])
        self.assertEqual([f.name for f in form.visible_fields()], ["artist", "name"])

    def test_hidden_initial_gets_id(self):
        class MyForm(Form):
            field1 = CharField(max_length=50, show_hidden_initial=True)

        self.assertHTMLEqual(
            MyForm().as_table(),
            '<tr><th><label for="id_field1">Field1:</label></th><td>'
            '<input id="id_field1" type="text" name="field1" maxlength="50" required>'
            '<input type="hidden" name="initial-field1" id="initial-id_field1">'
            "</td></tr>",
        )

    def test_error_html_required_html_classes(self):
        class Person(Form):
            name = CharField()
            is_cool = NullBooleanField()
            email = EmailField(required=False)
            age = IntegerField()

        p = Person({})
        p.error_css_class = "error"
        p.required_css_class = "required"

        self.assertHTMLEqual(
            p.as_ul(),
            """
            <li class="required error"><ul class="errorlist" id="id_name_error">
            <li>This field is required.</li></ul>
            <label class="required" for="id_name">Name:</label>
            <input type="text" name="name" id="id_name" aria-invalid="true" required
             aria-describedby="id_name_error">
            </li><li class="required">
            <label class="required" for="id_is_cool">Is cool:</label>
            <select name="is_cool" id="id_is_cool">
            <option value="unknown" selected>Unknown</option>
            <option value="true">Yes</option>
            <option value="false">No</option>
            </select></li>
            <li><label for="id_email">Email:</label>
            <input type="email" name="email" id="id_email" maxlength="320"></li>
            <li class="required error"><ul class="errorlist" id="id_age_error">
            <li>This field is required.</li></ul>
            <label class="required" for="id_age">Age:</label>
            <input type="number" name="age" id="id_age" aria-invalid="true" required
            aria-describedby="id_age_error">
            </li>""",
        )

        self.assertHTMLEqual(
            p.as_p(),
            """
            <ul class="errorlist" id="id_name_error"><li>This field is required.</li>
            </ul><p class="required error">
            <label class="required" for="id_name">Name:</label>
            <input type="text" name="name" id="id_name" aria-invalid="true" required
            aria-describedby="id_name_error">
            </p><p class="required">
            <label class="required" for="id_is_cool">Is cool:</label>
            <select name="is_cool" id="id_is_cool">
            <option value="unknown" selected>Unknown</option>
            <option value="true">Yes</option>
            <option value="false">No</option>
            </select></p>
            <p><label for="id_email">Email:</label>
            <input type="email" name="email" id="id_email" maxlength="320"></p>
            <ul class="errorlist" id="id_age_error"><li>This field is required.</li>
            </ul><p class="required error"><label class="required" for="id_age">
            Age:</label><input type="number" name="age" id="id_age" aria-invalid="true"
            required aria-describedby="id_age_error"></p>""",
        )

        self.assertHTMLEqual(
            p.as_table(),
            """<tr class="required error">
<th><label class="required" for="id_name">Name:</label></th>
<td><ul class="errorlist" id="id_name_error"><li>This field is required.</li></ul>
<input type="text" name="name" id="id_name" aria-invalid="true" required
aria-describedby="id_name_error"></td></tr>
<tr class="required"><th><label class="required" for="id_is_cool">Is cool:</label></th>
<td><select name="is_cool" id="id_is_cool">
<option value="unknown" selected>Unknown</option>
<option value="true">Yes</option>
<option value="false">No</option>
</select></td></tr>
<tr><th><label for="id_email">Email:</label></th><td>
<input type="email" name="email" id="id_email" maxlength="320"></td></tr>
<tr class="required error"><th><label class="required" for="id_age">Age:</label></th>
<td><ul class="errorlist" id="id_age_error"><li>This field is required.</li></ul>
<input type="number" name="age" id="id_age" aria-invalid="true" required
aria-describedby="id_age_error"></td></tr>""",
        )
        self.assertHTMLEqual(
            p.as_div(),
            '<div class="required error"><label for="id_name" class="required">Name:'
            '</label><ul class="errorlist" id="id_name_error"><li>This field is '
            'required.</li></ul><input type="text" name="name" required id="id_name" '
            'aria-invalid="true" aria-describedby="id_name_error" /></div>'
            '<div class="required"><label for="id_is_cool" class="required">Is cool:'
            '</label><select name="is_cool" id="id_is_cool">'
            '<option value="unknown" selected>Unknown</option>'
            '<option value="true">Yes</option><option value="false">No</option>'
            '</select></div><div><label for="id_email">Email:</label>'
            '<input type="email" name="email" id="id_email" maxlength="320"/></div>'
            '<div class="required error"><label for="id_age" class="required">Age:'
            '</label><ul class="errorlist" id="id_age_error"><li>This field is '
            'required.</li></ul><input type="number" name="age" required id="id_age" '
            'aria-invalid="true" aria-describedby="id_age_error" /></div>',
        )

    def test_label_has_required_css_class(self):
        """
        required_css_class is added to label_tag() and legend_tag() of required
        fields.
        """

        class SomeForm(Form):
            required_css_class = "required"
            field = CharField(max_length=10)
            field2 = IntegerField(required=False)

        f = SomeForm({"field": "test"})
        self.assertHTMLEqual(
            f["field"].label_tag(),
            '<label for="id_field" class="required">Field:</label>',
        )
        self.assertHTMLEqual(
            f["field"].legend_tag(),
            '<legend for="id_field" class="required">Field:</legend>',
        )
        self.assertHTMLEqual(
            f["field"].label_tag(attrs={"class": "foo"}),
            '<label for="id_field" class="foo required">Field:</label>',
        )
        self.assertHTMLEqual(
            f["field"].legend_tag(attrs={"class": "foo"}),
            '<legend for="id_field" class="foo required">Field:</legend>',
        )
        self.assertHTMLEqual(
            f["field2"].label_tag(), '<label for="id_field2">Field2:</label>'
        )
        self.assertHTMLEqual(
            f["field2"].legend_tag(),
            '<legend for="id_field2">Field2:</legend>',
        )

    def test_label_split_datetime_not_displayed(self):
        class EventForm(Form):
            happened_at = SplitDateTimeField(widget=SplitHiddenDateTimeWidget)

        form = EventForm()
        self.assertHTMLEqual(
            form.as_ul(),
            '<input type="hidden" name="happened_at_0" id="id_happened_at_0">'
            '<input type="hidden" name="happened_at_1" id="id_happened_at_1">',
        )

    def test_multivalue_field_validation(self):
        def bad_names(value):
            if value == "bad value":
                raise ValidationError("bad value not allowed")

        class NameField(MultiValueField):
            def __init__(self, fields=(), *args, **kwargs):
                fields = (
                    CharField(label="First name", max_length=10),
                    CharField(label="Last name", max_length=10),
                )
                super().__init__(fields=fields, *args, **kwargs)

            def compress(self, data_list):
                return " ".join(data_list)

        class NameForm(Form):
            name = NameField(validators=[bad_names])

        form = NameForm(data={"name": ["bad", "value"]})
        form.full_clean()
        self.assertFalse(form.is_valid())
        self.assertEqual(form.errors, {"name": ["bad value not allowed"]})
        form = NameForm(data={"name": ["should be overly", "long for the field names"]})
        self.assertFalse(form.is_valid())
        self.assertEqual(
            form.errors,
            {
                "name": [
                    "Ensure this value has at most 10 characters (it has 16).",
                    "Ensure this value has at most 10 characters (it has 24).",
                ],
            },
        )
        form = NameForm(data={"name": ["fname", "lname"]})
        self.assertTrue(form.is_valid())
        self.assertEqual(form.cleaned_data, {"name": "fname lname"})

    def test_multivalue_deep_copy(self):
        """
        #19298 -- MultiValueField needs to override the default as it needs
        to deep-copy subfields:
        """

        class ChoicesField(MultiValueField):
            def __init__(self, fields=(), *args, **kwargs):
                fields = (
                    ChoiceField(label="Rank", choices=((1, 1), (2, 2))),
                    CharField(label="Name", max_length=10),
                )
                super().__init__(fields=fields, *args, **kwargs)

        field = ChoicesField()
        field2 = copy.deepcopy(field)
        self.assertIsInstance(field2, ChoicesField)
        self.assertIsNot(field2.fields, field.fields)
        self.assertIsNot(field2.fields[0].choices, field.fields[0].choices)

    def test_multivalue_initial_data(self):
        """
        #23674 -- invalid initial data should not break form.changed_data()
        """

        class DateAgeField(MultiValueField):
            def __init__(self, fields=(), *args, **kwargs):
                fields = (DateField(label="Date"), IntegerField(label="Age"))
                super().__init__(fields=fields, *args, **kwargs)

        class DateAgeForm(Form):
            date_age = DateAgeField()

        data = {"date_age": ["1998-12-06", 16]}
        form = DateAgeForm(data, initial={"date_age": ["200-10-10", 14]})
        self.assertTrue(form.has_changed())

    def test_multivalue_optional_subfields(self):
        class PhoneField(MultiValueField):
            def __init__(self, *args, **kwargs):
                fields = (
                    CharField(
                        label="Country Code",
                        validators=[
                            RegexValidator(
                                r"^\+[0-9]{1,2}$", message="Enter a valid country code."
                            )
                        ],
                    ),
                    CharField(label="Phone Number"),
                    CharField(
                        label="Extension",
                        error_messages={"incomplete": "Enter an extension."},
                    ),
                    CharField(
                        label="Label", required=False, help_text="E.g. home, work."
                    ),
                )
                super().__init__(fields, *args, **kwargs)

            def compress(self, data_list):
                if data_list:
                    return "%s.%s ext. %s (label: %s)" % tuple(data_list)
                return None

        # An empty value for any field will raise a `required` error on a
        # required `MultiValueField`.
        f = PhoneField()
        with self.assertRaisesMessage(ValidationError, "'This field is required.'"):
            f.clean("")
        with self.assertRaisesMessage(ValidationError, "'This field is required.'"):
            f.clean(None)
        with self.assertRaisesMessage(ValidationError, "'This field is required.'"):
            f.clean([])
        with self.assertRaisesMessage(ValidationError, "'This field is required.'"):
            f.clean(["+61"])
        with self.assertRaisesMessage(ValidationError, "'This field is required.'"):
            f.clean(["+61", "287654321", "123"])
        self.assertEqual(
            "+61.287654321 ext. 123 (label: Home)",
            f.clean(["+61", "287654321", "123", "Home"]),
        )
        with self.assertRaisesMessage(ValidationError, "'Enter a valid country code.'"):
            f.clean(["61", "287654321", "123", "Home"])

        # Empty values for fields will NOT raise a `required` error on an
        # optional `MultiValueField`
        f = PhoneField(required=False)
        self.assertIsNone(f.clean(""))
        self.assertIsNone(f.clean(None))
        self.assertIsNone(f.clean([]))
        self.assertEqual("+61. ext.  (label: )", f.clean(["+61"]))
        self.assertEqual(
            "+61.287654321 ext. 123 (label: )", f.clean(["+61", "287654321", "123"])
        )
        self.assertEqual(
            "+61.287654321 ext. 123 (label: Home)",
            f.clean(["+61", "287654321", "123", "Home"]),
        )
        with self.assertRaisesMessage(ValidationError, "'Enter a valid country code.'"):
            f.clean(["61", "287654321", "123", "Home"])

        # For a required `MultiValueField` with `require_all_fields=False`, a
        # `required` error will only be raised if all fields are empty. Fields
        # can individually be required or optional. An empty value for any
        # required field will raise an `incomplete` error.
        f = PhoneField(require_all_fields=False)
        with self.assertRaisesMessage(ValidationError, "'This field is required.'"):
            f.clean("")
        with self.assertRaisesMessage(ValidationError, "'This field is required.'"):
            f.clean(None)
        with self.assertRaisesMessage(ValidationError, "'This field is required.'"):
            f.clean([])
        with self.assertRaisesMessage(ValidationError, "'Enter a complete value.'"):
            f.clean(["+61"])
        self.assertEqual(
            "+61.287654321 ext. 123 (label: )", f.clean(["+61", "287654321", "123"])
        )
        with self.assertRaisesMessage(
            ValidationError, "'Enter a complete value.', 'Enter an extension.'"
        ):
            f.clean(["", "", "", "Home"])
        with self.assertRaisesMessage(ValidationError, "'Enter a valid country code.'"):
            f.clean(["61", "287654321", "123", "Home"])

        # For an optional `MultiValueField` with `require_all_fields=False`, we
        # don't get any `required` error but we still get `incomplete` errors.
        f = PhoneField(required=False, require_all_fields=False)
        self.assertIsNone(f.clean(""))
        self.assertIsNone(f.clean(None))
        self.assertIsNone(f.clean([]))
        with self.assertRaisesMessage(ValidationError, "'Enter a complete value.'"):
            f.clean(["+61"])
        self.assertEqual(
            "+61.287654321 ext. 123 (label: )", f.clean(["+61", "287654321", "123"])
        )
        with self.assertRaisesMessage(
            ValidationError, "'Enter a complete value.', 'Enter an extension.'"
        ):
            f.clean(["", "", "", "Home"])
        with self.assertRaisesMessage(ValidationError, "'Enter a valid country code.'"):
            f.clean(["61", "287654321", "123", "Home"])

    def test_multivalue_optional_subfields_rendering(self):
        class PhoneWidget(MultiWidget):
            def __init__(self, attrs=None):
                widgets = [TextInput(), TextInput()]
                super().__init__(widgets, attrs)

            def decompress(self, value):
                return [None, None]

        class PhoneField(MultiValueField):
            def __init__(self, *args, **kwargs):
                fields = [CharField(), CharField(required=False)]
                super().__init__(fields, *args, **kwargs)

        class PhoneForm(Form):
            phone1 = PhoneField(widget=PhoneWidget)
            phone2 = PhoneField(widget=PhoneWidget, required=False)
            phone3 = PhoneField(widget=PhoneWidget, require_all_fields=False)
            phone4 = PhoneField(
                widget=PhoneWidget,
                required=False,
                require_all_fields=False,
            )

        form = PhoneForm(auto_id=False)
        self.assertHTMLEqual(
            form.as_p(),
            """
            <p>Phone1:<input type="text" name="phone1_0" required>
            <input type="text" name="phone1_1" required></p>
            <p>Phone2:<input type="text" name="phone2_0">
            <input type="text" name="phone2_1"></p>
            <p>Phone3:<input type="text" name="phone3_0" required>
            <input type="text" name="phone3_1"></p>
            <p>Phone4:<input type="text" name="phone4_0">
            <input type="text" name="phone4_1"></p>
            """,
        )

    def test_custom_empty_values(self):
        """
        Form fields can customize what is considered as an empty value
        for themselves (#19997).
        """

        class CustomJSONField(CharField):
            empty_values = [None, ""]

            def to_python(self, value):
                # Fake json.loads
                if value == "{}":
                    return {}
                return super().to_python(value)

        class JSONForm(Form):
            json = CustomJSONField()

        form = JSONForm(data={"json": "{}"})
        form.full_clean()
        self.assertEqual(form.cleaned_data, {"json": {}})

    def test_boundfield_label_tag(self):
        class SomeForm(Form):
            field = CharField()

        boundfield = SomeForm()["field"]

        testcases = [  # (args, kwargs, expected)
            # without anything: just print the <label>
            ((), {}, '<%(tag)s for="id_field">Field:</%(tag)s>'),
            # passing just one argument: overrides the field's label
            (("custom",), {}, '<%(tag)s for="id_field">custom:</%(tag)s>'),
            # the overridden label is escaped
            (("custom&",), {}, '<%(tag)s for="id_field">custom&amp;:</%(tag)s>'),
            ((mark_safe("custom&"),), {}, '<%(tag)s for="id_field">custom&:</%(tag)s>'),
            # Passing attrs to add extra attributes on the <label>
            (
                (),
                {"attrs": {"class": "pretty"}},
                '<%(tag)s for="id_field" class="pretty">Field:</%(tag)s>',
            ),
        ]

        for args, kwargs, expected in testcases:
            with self.subTest(args=args, kwargs=kwargs):
                self.assertHTMLEqual(
                    boundfield.label_tag(*args, **kwargs),
                    expected % {"tag": "label"},
                )
                self.assertHTMLEqual(
                    boundfield.legend_tag(*args, **kwargs),
                    expected % {"tag": "legend"},
                )

    def test_boundfield_label_tag_no_id(self):
        """
        If a widget has no id, label_tag() and legend_tag() return the text
        with no surrounding <label>.
        """

        class SomeForm(Form):
            field = CharField()

        boundfield = SomeForm(auto_id="")["field"]

        self.assertHTMLEqual(boundfield.label_tag(), "Field:")
        self.assertHTMLEqual(boundfield.legend_tag(), "Field:")
        self.assertHTMLEqual(boundfield.label_tag("Custom&"), "Custom&amp;:")
        self.assertHTMLEqual(boundfield.legend_tag("Custom&"), "Custom&amp;:")

    def test_boundfield_label_tag_custom_widget_id_for_label(self):
        class CustomIdForLabelTextInput(TextInput):
            def id_for_label(self, id):
                return "custom_" + id

        class EmptyIdForLabelTextInput(TextInput):
            def id_for_label(self, id):
                return None

        class SomeForm(Form):
            custom = CharField(widget=CustomIdForLabelTextInput)
            empty = CharField(widget=EmptyIdForLabelTextInput)

        form = SomeForm()
        self.assertHTMLEqual(
            form["custom"].label_tag(), '<label for="custom_id_custom">Custom:</label>'
        )
        self.assertHTMLEqual(
            form["custom"].legend_tag(),
            '<legend for="custom_id_custom">Custom:</legend>',
        )
        self.assertHTMLEqual(form["empty"].label_tag(), "<label>Empty:</label>")
        self.assertHTMLEqual(form["empty"].legend_tag(), "<legend>Empty:</legend>")

    def test_boundfield_empty_label(self):
        class SomeForm(Form):
            field = CharField(label="")

        boundfield = SomeForm()["field"]

        self.assertHTMLEqual(boundfield.label_tag(), '<label for="id_field"></label>')
        self.assertHTMLEqual(
            boundfield.legend_tag(),
            '<legend for="id_field"></legend>',
        )

    def test_boundfield_id_for_label(self):
        class SomeForm(Form):
            field = CharField(label="")

        self.assertEqual(SomeForm()["field"].id_for_label, "id_field")

    def test_boundfield_id_for_label_override_by_attrs(self):
        """
        If an id is provided in `Widget.attrs`, it overrides the generated ID,
        unless it is `None`.
        """

        class SomeForm(Form):
            field = CharField(widget=TextInput(attrs={"id": "myCustomID"}))
            field_none = CharField(widget=TextInput(attrs={"id": None}))

        form = SomeForm()
        self.assertEqual(form["field"].id_for_label, "myCustomID")
        self.assertEqual(form["field_none"].id_for_label, "id_field_none")

    def test_boundfield_subwidget_id_for_label(self):
        """
        If auto_id is provided when initializing the form, the generated ID in
        subwidgets must reflect that prefix.
        """

        class SomeForm(Form):
            field = MultipleChoiceField(
                choices=[("a", "A"), ("b", "B")],
                widget=CheckboxSelectMultiple,
            )

        form = SomeForm(auto_id="prefix_%s")
        subwidgets = form["field"].subwidgets
        self.assertEqual(subwidgets[0].id_for_label, "prefix_field_0")
        self.assertEqual(subwidgets[1].id_for_label, "prefix_field_1")

    def test_boundfield_widget_type(self):
        class SomeForm(Form):
            first_name = CharField()
            birthday = SplitDateTimeField(widget=SplitHiddenDateTimeWidget)

        f = SomeForm()
        self.assertEqual(f["first_name"].widget_type, "text")
        self.assertEqual(f["birthday"].widget_type, "splithiddendatetime")

    def test_boundfield_css_classes(self):
        form = Person()
        field = form["first_name"]
        self.assertEqual(field.css_classes(), "")
        self.assertEqual(field.css_classes(extra_classes=""), "")
        self.assertEqual(field.css_classes(extra_classes="test"), "test")
        self.assertEqual(field.css_classes(extra_classes="test test"), "test")

    def test_label_suffix_override(self):
        """
        BoundField label_suffix (if provided) overrides Form label_suffix
        """

        class SomeForm(Form):
            field = CharField()

        boundfield = SomeForm(label_suffix="!")["field"]

        self.assertHTMLEqual(
            boundfield.label_tag(label_suffix="$"),
            '<label for="id_field">Field$</label>',
        )
        self.assertHTMLEqual(
            boundfield.legend_tag(label_suffix="$"),
            '<legend for="id_field">Field$</legend>',
        )

    def test_error_dict(self):
        class MyForm(Form):
            foo = CharField()
            bar = CharField()

            def clean(self):
                raise ValidationError(
                    "Non-field error.", code="secret", params={"a": 1, "b": 2}
                )

        form = MyForm({})
        self.assertIs(form.is_valid(), False)

        errors = form.errors.as_text()
        control = [
            "* foo\n  * This field is required.",
            "* bar\n  * This field is required.",
            "* __all__\n  * Non-field error.",
        ]
        for error in control:
            self.assertIn(error, errors)

        errors = form.errors.as_ul()
        control = [
            '<li>foo<ul class="errorlist" id="id_foo_error"><li>This field is required.'
            "</li></ul></li>",
            '<li>bar<ul class="errorlist" id="id_bar_error"><li>This field is required.'
            "</li></ul></li>",
            '<li>__all__<ul class="errorlist nonfield"><li>Non-field error.</li></ul>'
            "</li>",
        ]
        for error in control:
            self.assertInHTML(error, errors)

        errors = form.errors.get_json_data()
        control = {
            "foo": [{"code": "required", "message": "This field is required."}],
            "bar": [{"code": "required", "message": "This field is required."}],
            "__all__": [{"code": "secret", "message": "Non-field error."}],
        }
        self.assertEqual(errors, control)
        self.assertEqual(json.dumps(errors), form.errors.as_json())

    def test_error_dict_as_json_escape_html(self):
        """#21962 - adding html escape flag to ErrorDict"""

        class MyForm(Form):
            foo = CharField()
            bar = CharField()

            def clean(self):
                raise ValidationError(
                    "<p>Non-field error.</p>",
                    code="secret",
                    params={"a": 1, "b": 2},
                )

        control = {
            "foo": [{"code": "required", "message": "This field is required."}],
            "bar": [{"code": "required", "message": "This field is required."}],
            "__all__": [{"code": "secret", "message": "<p>Non-field error.</p>"}],
        }

        form = MyForm({})
        self.assertFalse(form.is_valid())

        errors = json.loads(form.errors.as_json())
        self.assertEqual(errors, control)

        escaped_error = "&lt;p&gt;Non-field error.&lt;/p&gt;"
        self.assertEqual(
            form.errors.get_json_data(escape_html=True)["__all__"][0]["message"],
            escaped_error,
        )
        errors = json.loads(form.errors.as_json(escape_html=True))
        control["__all__"][0]["message"] = escaped_error
        self.assertEqual(errors, control)

    def test_error_list(self):
        e = ErrorList()
        e.append("Foo")
        e.append(ValidationError("Foo%(bar)s", code="foobar", params={"bar": "bar"}))

        self.assertIsInstance(e, list)
        self.assertIn("Foo", e)
        self.assertIn("Foo", ValidationError(e))

        self.assertEqual(e.as_text(), "* Foo\n* Foobar")

        self.assertEqual(
            e.as_ul(), '<ul class="errorlist"><li>Foo</li><li>Foobar</li></ul>'
        )

        errors = e.get_json_data()
        self.assertEqual(
            errors,
            [{"message": "Foo", "code": ""}, {"message": "Foobar", "code": "foobar"}],
        )
        self.assertEqual(json.dumps(errors), e.as_json())

    def test_error_list_class_not_specified(self):
        e = ErrorList()
        e.append("Foo")
        e.append(ValidationError("Foo%(bar)s", code="foobar", params={"bar": "bar"}))
        self.assertEqual(
            e.as_ul(), '<ul class="errorlist"><li>Foo</li><li>Foobar</li></ul>'
        )

    def test_error_list_class_has_one_class_specified(self):
        e = ErrorList(error_class="foobar-error-class")
        e.append("Foo")
        e.append(ValidationError("Foo%(bar)s", code="foobar", params={"bar": "bar"}))
        self.assertEqual(
            e.as_ul(),
            '<ul class="errorlist foobar-error-class"><li>Foo</li><li>Foobar</li></ul>',
        )

    def test_error_list_with_hidden_field_errors_has_correct_class(self):
        class Person(Form):
            first_name = CharField()
            last_name = CharField(widget=HiddenInput)

        p = Person({"first_name": "John"})
        self.assertHTMLEqual(
            p.as_ul(),
            """<li><ul class="errorlist nonfield">
<li>(Hidden field last_name) This field is required.</li></ul></li><li>
<label for="id_first_name">First name:</label>
<input id="id_first_name" name="first_name" type="text" value="John" required>
<input id="id_last_name" name="last_name" type="hidden"></li>""",
        )
        self.assertHTMLEqual(
            p.as_p(),
            """
            <ul class="errorlist nonfield">
            <li>(Hidden field last_name) This field is required.</li></ul>
            <p><label for="id_first_name">First name:</label>
            <input id="id_first_name" name="first_name" type="text" value="John"
                required>
            <input id="id_last_name" name="last_name" type="hidden"></p>
            """,
        )
        self.assertHTMLEqual(
            p.as_table(),
            """<tr><td colspan="2"><ul class="errorlist nonfield">
<li>(Hidden field last_name) This field is required.</li></ul></td></tr>
<tr><th><label for="id_first_name">First name:</label></th><td>
<input id="id_first_name" name="first_name" type="text" value="John" required>
<input id="id_last_name" name="last_name" type="hidden"></td></tr>""",
        )
        self.assertHTMLEqual(
            p.as_div(),
            '<ul class="errorlist nonfield"><li>(Hidden field last_name) This field '
            'is required.</li></ul><div><label for="id_first_name">First name:</label>'
            '<input id="id_first_name" name="first_name" type="text" value="John" '
            'required><input id="id_last_name" name="last_name" type="hidden"></div>',
        )

    def test_error_list_with_non_field_errors_has_correct_class(self):
        class Person(Form):
            first_name = CharField()
            last_name = CharField()

            def clean(self):
                raise ValidationError("Generic validation error")

        p = Person({"first_name": "John", "last_name": "Lennon"})
        self.assertHTMLEqual(
            str(p.non_field_errors()),
            '<ul class="errorlist nonfield"><li>Generic validation error</li></ul>',
        )
        self.assertHTMLEqual(
            p.as_ul(),
            """<li>
<ul class="errorlist nonfield"><li>Generic validation error</li></ul></li>
<li><label for="id_first_name">First name:</label>
<input id="id_first_name" name="first_name" type="text" value="John" required></li>
<li><label for="id_last_name">Last name:</label>
<input id="id_last_name" name="last_name" type="text" value="Lennon" required></li>""",
        )
        self.assertHTMLEqual(
            p.non_field_errors().as_text(), "* Generic validation error"
        )
        self.assertHTMLEqual(
            p.as_p(),
            """<ul class="errorlist nonfield"><li>Generic validation error</li></ul>
<p><label for="id_first_name">First name:</label>
<input id="id_first_name" name="first_name" type="text" value="John" required></p>
<p><label for="id_last_name">Last name:</label>
<input id="id_last_name" name="last_name" type="text" value="Lennon" required></p>""",
        )
        self.assertHTMLEqual(
            p.as_table(),
            """
            <tr><td colspan="2"><ul class="errorlist nonfield">
            <li>Generic validation error</li></ul></td></tr>
            <tr><th><label for="id_first_name">First name:</label></th><td>
            <input id="id_first_name" name="first_name" type="text" value="John"
                required>
            </td></tr>
            <tr><th><label for="id_last_name">Last name:</label></th><td>
            <input id="id_last_name" name="last_name" type="text" value="Lennon"
                required>
            </td></tr>
            """,
        )
        self.assertHTMLEqual(
            p.as_div(),
            '<ul class="errorlist nonfield"><li>Generic validation error</li></ul>'
            '<div><label for="id_first_name">First name:</label><input '
            'id="id_first_name" name="first_name" type="text" value="John" required>'
            '</div><div><label for="id_last_name">Last name:</label><input '
            'id="id_last_name" name="last_name" type="text" value="Lennon" required>'
            "</div>",
        )

    def test_error_escaping(self):
        class TestForm(Form):
            hidden = CharField(widget=HiddenInput(), required=False)
            visible = CharField()

            def clean_hidden(self):
                raise ValidationError('Foo & "bar"!')

            clean_visible = clean_hidden

        form = TestForm({"hidden": "a", "visible": "b"})
        form.is_valid()
        self.assertHTMLEqual(
            form.as_ul(),
            '<li><ul class="errorlist nonfield">'
            "<li>(Hidden field hidden) Foo &amp; &quot;bar&quot;!</li></ul></li>"
            '<li><ul class="errorlist" id="id_visible_error"><li>Foo &amp; '
            "&quot;bar&quot;!</li></ul>"
            '<label for="id_visible">Visible:</label> '
            '<input type="text" name="visible" aria-invalid="true" value="b" '
            'id="id_visible" required aria-describedby="id_visible_error">'
            '<input type="hidden" name="hidden" value="a" id="id_hidden"></li>',
        )

    def test_baseform_repr(self):
        """
        BaseForm.__repr__() should contain some basic information about the
        form.
        """
        p = Person()
        self.assertEqual(
            repr(p),
            "<Person bound=False, valid=Unknown, "
            "fields=(first_name;last_name;birthday)>",
        )
        p = Person(
            {"first_name": "John", "last_name": "Lennon", "birthday": "1940-10-9"}
        )
        self.assertEqual(
            repr(p),
            "<Person bound=True, valid=Unknown, "
            "fields=(first_name;last_name;birthday)>",
        )
        p.is_valid()
        self.assertEqual(
            repr(p),
            "<Person bound=True, valid=True, fields=(first_name;last_name;birthday)>",
        )
        p = Person(
            {"first_name": "John", "last_name": "Lennon", "birthday": "fakedate"}
        )
        p.is_valid()
        self.assertEqual(
            repr(p),
            "<Person bound=True, valid=False, fields=(first_name;last_name;birthday)>",
        )

    def test_baseform_repr_dont_trigger_validation(self):
        """
        BaseForm.__repr__() shouldn't trigger the form validation.
        """
        p = Person(
            {"first_name": "John", "last_name": "Lennon", "birthday": "fakedate"}
        )
        repr(p)
        with self.assertRaises(AttributeError):
            p.cleaned_data
        self.assertFalse(p.is_valid())
        self.assertEqual(p.cleaned_data, {"first_name": "John", "last_name": "Lennon"})

    def test_accessing_clean(self):
        class UserForm(Form):
            username = CharField(max_length=10)
            password = CharField(widget=PasswordInput)

            def clean(self):
                data = self.cleaned_data

                if not self.errors:
                    data["username"] = data["username"].lower()

                return data

        f = UserForm({"username": "SirRobin", "password": "blue"})
        self.assertTrue(f.is_valid())
        self.assertEqual(f.cleaned_data["username"], "sirrobin")

    def test_changing_cleaned_data_nothing_returned(self):
        class UserForm(Form):
            username = CharField(max_length=10)
            password = CharField(widget=PasswordInput)

            def clean(self):
                self.cleaned_data["username"] = self.cleaned_data["username"].lower()
                # don't return anything

        f = UserForm({"username": "SirRobin", "password": "blue"})
        self.assertTrue(f.is_valid())
        self.assertEqual(f.cleaned_data["username"], "sirrobin")

    def test_changing_cleaned_data_in_clean(self):
        class UserForm(Form):
            username = CharField(max_length=10)
            password = CharField(widget=PasswordInput)

            def clean(self):
                data = self.cleaned_data

                # Return a different dict. We have not changed
                # self.cleaned_data.
                return {
                    "username": data["username"].lower(),
                    "password": "this_is_not_a_secret",
                }

        f = UserForm({"username": "SirRobin", "password": "blue"})
        self.assertTrue(f.is_valid())
        self.assertEqual(f.cleaned_data["username"], "sirrobin")

    def test_multipart_encoded_form(self):
        class FormWithoutFile(Form):
            username = CharField()

        class FormWithFile(Form):
            username = CharField()
            file = FileField()

        class FormWithImage(Form):
            image = ImageField()

        self.assertFalse(FormWithoutFile().is_multipart())
        self.assertTrue(FormWithFile().is_multipart())
        self.assertTrue(FormWithImage().is_multipart())

    def test_html_safe(self):
        class SimpleForm(Form):
            username = CharField()

        form = SimpleForm()
        self.assertTrue(hasattr(SimpleForm, "__html__"))
        self.assertEqual(str(form), form.__html__())
        self.assertTrue(hasattr(form["username"], "__html__"))
        self.assertEqual(str(form["username"]), form["username"].__html__())

    def test_use_required_attribute_true(self):
        class MyForm(Form):
            use_required_attribute = True
            f1 = CharField(max_length=30)
            f2 = CharField(max_length=30, required=False)
            f3 = CharField(widget=Textarea)
            f4 = ChoiceField(choices=[("P", "Python"), ("J", "Java")])

        form = MyForm()
        self.assertHTMLEqual(
            form.as_p(),
            '<p><label for="id_f1">F1:</label>'
            '<input id="id_f1" maxlength="30" name="f1" type="text" required></p>'
            '<p><label for="id_f2">F2:</label>'
            '<input id="id_f2" maxlength="30" name="f2" type="text"></p>'
            '<p><label for="id_f3">F3:</label>'
            '<textarea cols="40" id="id_f3" name="f3" rows="10" required>'
            "</textarea></p>"
            '<p><label for="id_f4">F4:</label> <select id="id_f4" name="f4">'
            '<option value="P">Python</option>'
            '<option value="J">Java</option>'
            "</select></p>",
        )
        self.assertHTMLEqual(
            form.as_ul(),
            '<li><label for="id_f1">F1:</label> '
            '<input id="id_f1" maxlength="30" name="f1" type="text" required></li>'
            '<li><label for="id_f2">F2:</label>'
            '<input id="id_f2" maxlength="30" name="f2" type="text"></li>'
            '<li><label for="id_f3">F3:</label>'
            '<textarea cols="40" id="id_f3" name="f3" rows="10" required>'
            "</textarea></li>"
            '<li><label for="id_f4">F4:</label> <select id="id_f4" name="f4">'
            '<option value="P">Python</option>'
            '<option value="J">Java</option>'
            "</select></li>",
        )
        self.assertHTMLEqual(
            form.as_table(),
            '<tr><th><label for="id_f1">F1:</label></th>'
            '<td><input id="id_f1" maxlength="30" name="f1" type="text" required>'
            "</td></tr>"
            '<tr><th><label for="id_f2">F2:</label></th>'
            '<td><input id="id_f2" maxlength="30" name="f2" type="text"></td></tr>'
            '<tr><th><label for="id_f3">F3:</label></th>'
            '<td><textarea cols="40" id="id_f3" name="f3" rows="10" required>'
            "</textarea></td></tr>"
            '<tr><th><label for="id_f4">F4:</label></th><td>'
            '<select id="id_f4" name="f4">'
            '<option value="P">Python</option>'
            '<option value="J">Java</option>'
            "</select></td></tr>",
        )
        self.assertHTMLEqual(
            form.render(form.template_name_div),
            '<div><label for="id_f1">F1:</label><input id="id_f1" maxlength="30" '
            'name="f1" type="text" required></div><div><label for="id_f2">F2:</label>'
            '<input id="id_f2" maxlength="30" name="f2" type="text"></div><div><label '
            'for="id_f3">F3:</label><textarea cols="40" id="id_f3" name="f3" '
            'rows="10" required></textarea></div><div><label for="id_f4">F4:</label>'
            '<select id="id_f4" name="f4"><option value="P">Python</option>'
            '<option value="J">Java</option></select></div>',
        )

    def test_use_required_attribute_false(self):
        class MyForm(Form):
            use_required_attribute = False
            f1 = CharField(max_length=30)
            f2 = CharField(max_length=30, required=False)
            f3 = CharField(widget=Textarea)
            f4 = ChoiceField(choices=[("P", "Python"), ("J", "Java")])

        form = MyForm()
        self.assertHTMLEqual(
            form.as_p(),
            '<p><label for="id_f1">F1:</label>'
            '<input id="id_f1" maxlength="30" name="f1" type="text"></p>'
            '<p><label for="id_f2">F2:</label>'
            '<input id="id_f2" maxlength="30" name="f2" type="text"></p>'
            '<p><label for="id_f3">F3:</label>'
            '<textarea cols="40" id="id_f3" name="f3" rows="10"></textarea></p>'
            '<p><label for="id_f4">F4:</label> <select id="id_f4" name="f4">'
            '<option value="P">Python</option>'
            '<option value="J">Java</option>'
            "</select></p>",
        )
        self.assertHTMLEqual(
            form.as_ul(),
            '<li><label for="id_f1">F1:</label>'
            '<input id="id_f1" maxlength="30" name="f1" type="text"></li>'
            '<li><label for="id_f2">F2:</label>'
            '<input id="id_f2" maxlength="30" name="f2" type="text"></li>'
            '<li><label for="id_f3">F3:</label>'
            '<textarea cols="40" id="id_f3" name="f3" rows="10"></textarea></li>'
            '<li><label for="id_f4">F4:</label> <select id="id_f4" name="f4">'
            '<option value="P">Python</option>'
            '<option value="J">Java</option>'
            "</select></li>",
        )
        self.assertHTMLEqual(
            form.as_table(),
            '<tr><th><label for="id_f1">F1:</label></th>'
            '<td><input id="id_f1" maxlength="30" name="f1" type="text"></td></tr>'
            '<tr><th><label for="id_f2">F2:</label></th>'
            '<td><input id="id_f2" maxlength="30" name="f2" type="text"></td></tr>'
            '<tr><th><label for="id_f3">F3:</label></th><td>'
            '<textarea cols="40" id="id_f3" name="f3" rows="10">'
            "</textarea></td></tr>"
            '<tr><th><label for="id_f4">F4:</label></th><td>'
            '<select id="id_f4" name="f4">'
            '<option value="P">Python</option>'
            '<option value="J">Java</option>'
            "</select></td></tr>",
        )
        self.assertHTMLEqual(
            form.render(form.template_name_div),
            '<div><label for="id_f1">F1:</label> <input id="id_f1" maxlength="30" '
            'name="f1" type="text"></div><div><label for="id_f2">F2:</label>'
            '<input id="id_f2" maxlength="30" name="f2" type="text"></div><div>'
            '<label for="id_f3">F3:</label> <textarea cols="40" id="id_f3" name="f3" '
            'rows="10"></textarea></div><div><label for="id_f4">F4:</label>'
            '<select id="id_f4" name="f4"><option value="P">Python</option>'
            '<option value="J">Java</option></select></div>',
        )

    def test_only_hidden_fields(self):
        # A form with *only* hidden fields that has errors is going to be very
        # unusual.
        class HiddenForm(Form):
            data = IntegerField(widget=HiddenInput)

        f = HiddenForm({})
        self.assertHTMLEqual(
            f.as_p(),
            '<ul class="errorlist nonfield">'
            "<li>(Hidden field data) This field is required.</li></ul>\n<p> "
            '<input type="hidden" name="data" id="id_data"></p>',
        )
        self.assertHTMLEqual(
            f.as_table(),
            '<tr><td colspan="2"><ul class="errorlist nonfield">'
            "<li>(Hidden field data) This field is required.</li></ul>"
            '<input type="hidden" name="data" id="id_data"></td></tr>',
        )

    def test_field_named_data(self):
        class DataForm(Form):
            data = CharField(max_length=10)

        f = DataForm({"data": "xyzzy"})
        self.assertTrue(f.is_valid())
        self.assertEqual(f.cleaned_data, {"data": "xyzzy"})

    def test_empty_data_files_multi_value_dict(self):
        p = Person()
        self.assertIsInstance(p.data, MultiValueDict)
        self.assertIsInstance(p.files, MultiValueDict)

    def test_field_deep_copy_error_messages(self):
        class CustomCharField(CharField):
            def __init__(self, **kwargs):
                kwargs["error_messages"] = {"invalid": "Form custom error message."}
                super().__init__(**kwargs)

        field = CustomCharField()
        field_copy = copy.deepcopy(field)
        self.assertIsInstance(field_copy, CustomCharField)
        self.assertIsNot(field_copy.error_messages, field.error_messages)

    def test_label_does_not_include_new_line(self):
        form = Person()
        field = form["first_name"]
        self.assertEqual(
            field.label_tag(), '<label for="id_first_name">First name:</label>'
        )
        self.assertEqual(
            field.legend_tag(),
            '<legend for="id_first_name">First name:</legend>',
        )

    @override_settings(USE_THOUSAND_SEPARATOR=True)
    def test_label_attrs_not_localized(self):
        form = Person()
        field = form["first_name"]
        self.assertHTMLEqual(
            field.label_tag(attrs={"number": 9999}),
            '<label number="9999" for="id_first_name">First name:</label>',
        )
        self.assertHTMLEqual(
            field.legend_tag(attrs={"number": 9999}),
            '<legend number="9999" for="id_first_name">First name:</legend>',
        )

    def test_remove_cached_field(self):
        class TestForm(Form):
            name = CharField(max_length=10)

            def __init__(self, *args, **kwargs):
                super().__init__(*args, **kwargs)
                # Populate fields cache.
                [field for field in self]
                # Removed cached field.
                del self.fields["name"]

        f = TestForm({"name": "abcde"})

        with self.assertRaises(KeyError):
            f["name"]

    def test_aria_describedby_property(self):
        class TestForm(Form):
            name = CharField(help_text="Some help text")

        form = TestForm({"name": "MyName"})
        self.assertEqual(form["name"].aria_describedby, "id_name_helptext")

        form = TestForm(auto_id=None)
        self.assertEqual(form["name"].aria_describedby, "")

        class TestFormHidden(Form):
            name = CharField(help_text="Some help text", widget=HiddenInput)

        form = TestFormHidden()
        self.assertEqual(form["name"].aria_describedby, "")

        class TestFormWithAttrs(Form):
            name = CharField(widget=TextInput(attrs={"aria-describedby": "my-id"}))

        form = TestFormWithAttrs({"name": "MyName"})
        self.assertIs(form["name"].aria_describedby, None)

        class TestFormWithoutHelpText(Form):
            name = CharField()

        form = TestFormWithoutHelpText()
        self.assertEqual(form["name"].aria_describedby, "")


@jinja2_tests
class Jinja2FormsTestCase(FormsTestCase):
    pass


class CustomRenderer(DjangoTemplates):
    form_template_name = "forms_tests/form_snippet.html"
    field_template_name = "forms_tests/custom_field.html"


class RendererTests(SimpleTestCase):
    def test_default(self):
        form = Form()
        self.assertEqual(form.renderer, get_default_renderer())

    def test_kwarg_instance(self):
        custom = CustomRenderer()
        form = Form(renderer=custom)
        self.assertEqual(form.renderer, custom)

    def test_kwarg_class(self):
        custom = CustomRenderer()
        form = Form(renderer=custom)
        self.assertEqual(form.renderer, custom)

    def test_attribute_instance(self):
        class CustomForm(Form):
            default_renderer = DjangoTemplates()

        form = CustomForm()
        self.assertEqual(form.renderer, CustomForm.default_renderer)

    def test_attribute_class(self):
        class CustomForm(Form):
            default_renderer = CustomRenderer

        form = CustomForm()
        self.assertIsInstance(form.renderer, CustomForm.default_renderer)

    def test_attribute_override(self):
        class CustomForm(Form):
            default_renderer = DjangoTemplates()

        custom = CustomRenderer()
        form = CustomForm(renderer=custom)
        self.assertEqual(form.renderer, custom)

    def test_get_context_errors(self):
        custom = CustomRenderer()
        form = Form(renderer=custom)
        context = form.get_context()
        self.assertEqual(context["errors"].renderer, custom)

    def test_boundfield_fallback(self):
        class RendererWithoutBoundFieldClassAttribute:
            form_template_name = "django/forms/div.html"
            formset_template_name = "django/forms/formsets/div.html"
            field_template_name = "django/forms/field.html"

            def render(self, template_name, context, request=None):
                return "Nice"

        class UserForm(Form):
            name = CharField()

        form = UserForm(renderer=RendererWithoutBoundFieldClassAttribute())
        self.assertIsInstance(form["name"], BoundField)
        self.assertEqual(form["name"].as_field_group(), "Nice")


class TemplateTests(SimpleTestCase):
    def test_iterate_radios(self):
        f = FrameworkForm(auto_id="id_%s")
        t = Template(
            "{% for radio in form.language %}"
            '<div class="myradio">{{ radio }}</div>'
            "{% endfor %}"
        )
        self.assertHTMLEqual(
            t.render(Context({"form": f})),
            '<div class="myradio"><label for="id_language_0">'
            '<input id="id_language_0" name="language" type="radio" value="P" '
            "required> Python</label></div>"
            '<div class="myradio"><label for="id_language_1">'
            '<input id="id_language_1" name="language" type="radio" value="J" '
            "required> Java</label></div>",
        )

    def test_iterate_checkboxes(self):
        f = SongForm({"composers": ["J", "P"]}, auto_id=False)
        t = Template(
            "{% for checkbox in form.composers %}"
            '<div class="mycheckbox">{{ checkbox }}</div>'
            "{% endfor %}"
        )
        self.assertHTMLEqual(
            t.render(Context({"form": f})),
            '<div class="mycheckbox"><label>'
            '<input checked name="composers" type="checkbox" value="J"> '
            "John Lennon</label></div>"
            '<div class="mycheckbox"><label>'
            '<input checked name="composers" type="checkbox" value="P"> '
            "Paul McCartney</label></div>",
        )

    def test_templates_with_forms(self):
        class UserRegistration(Form):
            username = CharField(
                max_length=10,
                help_text=("Good luck picking a username that doesn't already exist."),
            )
            password1 = CharField(widget=PasswordInput)
            password2 = CharField(widget=PasswordInput)

            def clean(self):
                if (
                    self.cleaned_data.get("password1")
                    and self.cleaned_data.get("password2")
                    and self.cleaned_data["password1"] != self.cleaned_data["password2"]
                ):
                    raise ValidationError("Please make sure your passwords match.")
                return self.cleaned_data

        # There is full flexibility in displaying form fields in a template.
        # Just pass a Form instance to the template, and use "dot" access to
        # refer to individual fields. However, this flexibility comes with the
        # responsibility of displaying all the errors, including any that might
        # not be associated with a particular field.
        t = Template(
            "<form>"
            "{{ form.username.errors.as_ul }}"
            "<p><label>Your username: {{ form.username }}</label></p>"
            "{{ form.password1.errors.as_ul }}"
            "<p><label>Password: {{ form.password1 }}</label></p>"
            "{{ form.password2.errors.as_ul }}"
            "<p><label>Password (again): {{ form.password2 }}</label></p>"
            '<input type="submit" required>'
            "</form>"
        )
        f = UserRegistration(auto_id=False)
        self.assertHTMLEqual(
            t.render(Context({"form": f})),
            "<form>"
            "<p><label>Your username: "
            '<input type="text" name="username" maxlength="10" required></label></p>'
            "<p><label>Password: "
            '<input type="password" name="password1" required></label></p>'
            "<p><label>Password (again): "
            '<input type="password" name="password2" required></label></p>'
            '<input type="submit" required>'
            "</form>",
        )
        f = UserRegistration({"username": "django"}, auto_id=False)
        self.assertHTMLEqual(
            t.render(Context({"form": f})),
            "<form>"
            "<p><label>Your username: "
            '<input type="text" name="username" value="django" maxlength="10" required>'
            "</label></p>"
            '<ul class="errorlist"><li>This field is required.</li></ul><p>'
            "<label>Password: "
            '<input type="password" name="password1" aria-invalid="true" required>'
            "</label></p>"
            '<ul class="errorlist"><li>This field is required.</li></ul>'
            "<p><label>Password (again): "
            '<input type="password" name="password2" aria-invalid="true" required>'
            "</label></p>"
            '<input type="submit" required>'
            "</form>",
        )
        # Use form.[field].label to output a field's label. 'label' for a field
        # can by specified by using the 'label' argument to a Field class. If
        # 'label' is not specified, Django will use the field name with
        # underscores converted to spaces, and the initial letter capitalized.
        t = Template(
            "<form>"
            "<p><label>{{ form.username.label }}: {{ form.username }}</label></p>"
            "<p><label>{{ form.password1.label }}: {{ form.password1 }}</label></p>"
            "<p><label>{{ form.password2.label }}: {{ form.password2 }}</label></p>"
            '<input type="submit" required>'
            "</form>"
        )
        f = UserRegistration(auto_id=False)
        self.assertHTMLEqual(
            t.render(Context({"form": f})),
            "<form>"
            "<p><label>Username: "
            '<input type="text" name="username" maxlength="10" required></label></p>'
            "<p><label>Password1: "
            '<input type="password" name="password1" required></label></p>'
            "<p><label>Password2: "
            '<input type="password" name="password2" required></label></p>'
            '<input type="submit" required>'
            "</form>",
        )
        # Use form.[field].label_tag to output a field's label with a <label>
        # tag wrapped around it, but *only* if the given field has an "id"
        # attribute. Recall from above that passing the "auto_id" argument to a
        # Form gives each field an "id" attribute.
        t = Template(
            "<form>"
            "<p>{{ form.username.label_tag }} {{ form.username }}"
            '<span {% if form.username.id_for_label %}id="'
            '{{ form.username.id_for_label }}_helptext"{% endif %}>'
            "{{ form.username.help_text}}</span></p>"
            "<p>{{ form.password1.label_tag }} {{ form.password1 }}</p>"
            "<p>{{ form.password2.label_tag }} {{ form.password2 }}</p>"
            '<input type="submit" required>'
            "</form>"
        )
        self.assertHTMLEqual(
            t.render(Context({"form": f})),
            "<form>"
            "<p>Username: "
            '<input type="text" name="username" maxlength="10" required>'
            "<span>Good luck picking a username that doesn't already exist.</span></p>"
            '<p>Password1: <input type="password" name="password1" required></p>'
            '<p>Password2: <input type="password" name="password2" required></p>'
            '<input type="submit" required>'
            "</form>",
        )
        f = UserRegistration(auto_id="id_%s")
        self.assertHTMLEqual(
            t.render(Context({"form": f})),
            "<form>"
            '<p><label for="id_username">Username:</label>'
            '<input id="id_username" type="text" name="username" maxlength="10" '
            'aria-describedby="id_username_helptext" required>'
            '<span id="id_username_helptext">'
            "Good luck picking a username that doesn't already exist.</span></p>"
            '<p><label for="id_password1">Password1:</label>'
            '<input type="password" name="password1" id="id_password1" required></p>'
            '<p><label for="id_password2">Password2:</label>'
            '<input type="password" name="password2" id="id_password2" required></p>'
            '<input type="submit" required>'
            "</form>",
        )
        # Use form.[field].legend_tag to output a field's label with a <legend>
        # tag wrapped around it, but *only* if the given field has an "id"
        # attribute. Recall from above that passing the "auto_id" argument to a
        # Form gives each field an "id" attribute.
        t = Template(
            "<form>"
            "<p>{{ form.username.legend_tag }} {{ form.username }}</p>"
            "<p>{{ form.password1.legend_tag }} {{ form.password1 }}</p>"
            "<p>{{ form.password2.legend_tag }} {{ form.password2 }}</p>"
            '<input type="submit" required>'
            "</form>"
        )
        f = UserRegistration(auto_id=False)
        self.assertHTMLEqual(
            t.render(Context({"form": f})),
            "<form>"
            "<p>Username: "
            '<input type="text" name="username" maxlength="10" required></p>'
            '<p>Password1: <input type="password" name="password1" required></p>'
            '<p>Password2: <input type="password" name="password2" required></p>'
            '<input type="submit" required>'
            "</form>",
        )
        f = UserRegistration(auto_id="id_%s")
        self.assertHTMLEqual(
            t.render(Context({"form": f})),
            "<form>"
            '<p><legend for="id_username">Username:</legend>'
            '<input id="id_username" type="text" name="username" maxlength="10" '
            'aria-describedby="id_username_helptext" required></p>'
            '<p><legend for="id_password1">Password1:</legend>'
            '<input type="password" name="password1" id="id_password1" required></p>'
            '<p><legend for="id_password2">Password2:</legend>'
            '<input type="password" name="password2" id="id_password2" required></p>'
            '<input type="submit" required>'
            "</form>",
        )
        # Use form.[field].help_text to output a field's help text. If the
        # given field does not have help text, nothing will be output.
        t = Template(
            "<form>"
            "<p>{{ form.username.label_tag }} {{ form.username }}<br>"
            "{{ form.username.help_text }}</p>"
            "<p>{{ form.password1.label_tag }} {{ form.password1 }}</p>"
            "<p>{{ form.password2.label_tag }} {{ form.password2 }}</p>"
            '<input type="submit" required>'
            "</form>"
        )
        f = UserRegistration(auto_id=False)
        self.assertHTMLEqual(
            t.render(Context({"form": f})),
            "<form>"
            "<p>Username: "
            '<input type="text" name="username" maxlength="10" required><br>'
            "Good luck picking a username that doesn&#x27;t already exist.</p>"
            '<p>Password1: <input type="password" name="password1" required></p>'
            '<p>Password2: <input type="password" name="password2" required></p>'
            '<input type="submit" required>'
            "</form>",
        )
        self.assertEqual(
            Template("{{ form.password1.help_text }}").render(Context({"form": f})),
            "",
        )
        # To display the errors that aren't associated with a particular field
        # e.g. the errors caused by Form.clean() -- use
        # {{ form.non_field_errors }} in the template. If used on its own, it
        # is displayed as a <ul> (or an empty string, if the list of errors is
        # empty).
        t = Template(
            "<form>"
            "{{ form.username.errors.as_ul }}"
            "<p><label>Your username: {{ form.username }}</label></p>"
            "{{ form.password1.errors.as_ul }}"
            "<p><label>Password: {{ form.password1 }}</label></p>"
            "{{ form.password2.errors.as_ul }}"
            "<p><label>Password (again): {{ form.password2 }}</label></p>"
            '<input type="submit" required>'
            "</form>"
        )
        f = UserRegistration(
            {"username": "django", "password1": "foo", "password2": "bar"},
            auto_id=False,
        )
        self.assertHTMLEqual(
            t.render(Context({"form": f})),
            "<form>"
            "<p><label>Your username: "
            '<input type="text" name="username" value="django" maxlength="10" required>'
            "</label></p>"
            "<p><label>Password: "
            '<input type="password" name="password1" required></label></p>'
            "<p><label>Password (again): "
            '<input type="password" name="password2" required></label></p>'
            '<input type="submit" required>'
            "</form>",
        )
        t = Template(
            "<form>"
            "{{ form.non_field_errors }}"
            "{{ form.username.errors.as_ul }}"
            "<p><label>Your username: {{ form.username }}</label></p>"
            "{{ form.password1.errors.as_ul }}"
            "<p><label>Password: {{ form.password1 }}</label></p>"
            "{{ form.password2.errors.as_ul }}"
            "<p><label>Password (again): {{ form.password2 }}</label></p>"
            '<input type="submit" required>'
            "</form>"
        )
        self.assertHTMLEqual(
            t.render(Context({"form": f})),
            "<form>"
            '<ul class="errorlist nonfield">'
            "<li>Please make sure your passwords match.</li></ul>"
            "<p><label>Your username: "
            '<input type="text" name="username" value="django" maxlength="10" required>'
            "</label></p>"
            "<p><label>Password: "
            '<input type="password" name="password1" required></label></p>'
            "<p><label>Password (again): "
            '<input type="password" name="password2" required></label></p>'
            '<input type="submit" required>'
            "</form>",
        )

    def test_basic_processing_in_view(self):
        class UserRegistration(Form):
            username = CharField(max_length=10)
            password1 = CharField(widget=PasswordInput)
            password2 = CharField(widget=PasswordInput)

            def clean(self):
                if (
                    self.cleaned_data.get("password1")
                    and self.cleaned_data.get("password2")
                    and self.cleaned_data["password1"] != self.cleaned_data["password2"]
                ):
                    raise ValidationError("Please make sure your passwords match.")
                return self.cleaned_data

        def my_function(method, post_data):
            if method == "POST":
                form = UserRegistration(post_data, auto_id=False)
            else:
                form = UserRegistration(auto_id=False)

            if form.is_valid():
                return "VALID: %r" % sorted(form.cleaned_data.items())

            t = Template(
                '<form method="post">'
                "{{ form }}"
                '<input type="submit" required>'
                "</form>"
            )
            return t.render(Context({"form": form}))

        # GET with an empty form and no errors.
        self.assertHTMLEqual(
            my_function("GET", {}),
            '<form method="post">'
            "<div>Username:"
            '<input type="text" name="username" maxlength="10" required></div>'
            "<div>Password1:"
            '<input type="password" name="password1" required></div>'
            "<div>Password2:"
            '<input type="password" name="password2" required></div>'
            '<input type="submit" required>'
            "</form>",
        )
        # POST with erroneous data, a redisplayed form, with errors.
        self.assertHTMLEqual(
            my_function(
                "POST",
                {
                    "username": "this-is-a-long-username",
                    "password1": "foo",
                    "password2": "bar",
                },
            ),
            '<form method="post">'
            '<ul class="errorlist nonfield">'
            "<li>Please make sure your passwords match.</li></ul>"
            '<div>Username:<ul class="errorlist">'
            "<li>Ensure this value has at most 10 characters (it has 23).</li></ul>"
            '<input type="text" name="username" aria-invalid="true" '
            'value="this-is-a-long-username" maxlength="10" required></div>'
            "<div>Password1:"
            '<input type="password" name="password1" required></div>'
            "<div>Password2:"
            '<input type="password" name="password2" required></div>'
            '<input type="submit" required>'
            "</form>",
        )
        # POST with valid data (the success message).
        self.assertEqual(
            my_function(
                "POST",
                {
                    "username": "adrian",
                    "password1": "secret",
                    "password2": "secret",
                },
            ),
            "VALID: [('password1', 'secret'), ('password2', 'secret'), "
            "('username', 'adrian')]",
        )

    def test_custom_field_template(self):
        class MyForm(Form):
            first_name = CharField(template_name="forms_tests/custom_field.html")

        f = MyForm()
        self.assertHTMLEqual(
            f.render(),
            '<div><label for="id_first_name">First name:</label><p>Custom Field</p>'
            '<input type="text" name="first_name" required id="id_first_name"></div>',
        )

    def test_custom_field_render_template(self):
        class MyForm(Form):
            first_name = CharField()

        f = MyForm()
        self.assertHTMLEqual(
            f["first_name"].render(template_name="forms_tests/custom_field.html"),
            '<label for="id_first_name">First name:</label><p>Custom Field</p>'
            '<input type="text" name="first_name" required id="id_first_name">',
        )


class OverrideTests(SimpleTestCase):
    @override_settings(FORM_RENDERER="forms_tests.tests.test_forms.CustomRenderer")
    def test_custom_renderer_template_name(self):
        class Person(Form):
            first_name = CharField()

        t = Template("{{ form }}")
        html = t.render(Context({"form": Person()}))
        expected = """
        <div class="fieldWrapper"><label for="id_first_name">First name:</label>
        <input type="text" name="first_name" required id="id_first_name"></div>
        """
        self.assertHTMLEqual(html, expected)

    @override_settings(FORM_RENDERER="forms_tests.tests.test_forms.CustomRenderer")
    def test_custom_renderer_field_template_name(self):
        class Person(Form):
            first_name = CharField()

        t = Template("{{ form.first_name.as_field_group }}")
        html = t.render(Context({"form": Person()}))
        expected = """
        <label for="id_first_name">First name:</label>
        <p>Custom Field</p>
        <input type="text" name="first_name" required id="id_first_name">
        """
        self.assertHTMLEqual(html, expected)

    def test_per_form_template_name(self):
        class Person(Form):
            first_name = CharField()
            template_name = "forms_tests/form_snippet.html"

        t = Template("{{ form }}")
        html = t.render(Context({"form": Person()}))
        expected = """
        <div class="fieldWrapper"><label for="id_first_name">First name:</label>
        <input type="text" name="first_name" required id="id_first_name"></div>
        """
        self.assertHTMLEqual(html, expected)

    def test_errorlist_override(self):
        class CustomErrorList(ErrorList):
            template_name = "forms_tests/error.html"

        class CommentForm(Form):
            name = CharField(max_length=50, required=False)
            email = EmailField()
            comment = CharField()

        data = {"email": "invalid"}
        f = CommentForm(data, auto_id=False, error_class=CustomErrorList)
        self.assertHTMLEqual(
            f.as_p(),
            '<p>Name: <input type="text" name="name" maxlength="50"></p>'
            '<div class="errorlist">'
            '<div class="error">Enter a valid email address.</div></div>'
            "<p>Email: "
            '<input type="email" name="email" value="invalid" maxlength="320" '
            'aria-invalid="true" required></p><div class="errorlist">'
            '<div class="error">This field is required.</div></div>'
            '<p>Comment: <input type="text" name="comment" aria-invalid="true" '
            "required></p>",
        )

    def test_custom_renderer_error_dict(self):
        class CustomRenderer(DjangoTemplates):
            def render(self, template_name, context, request=None):
                if template_name == "django/forms/errors/dict/default.html":
                    return "<strong>So many errors!</strong>"
                return super().render(template_name, context, request)

        form = Form({}, renderer=CustomRenderer())
        form.full_clean()
        form.add_error(None, "Test error")

        self.assertHTMLEqual(
            form.errors.render(),
            "<strong>So many errors!</strong>",
        )

    def test_cyclic_context_boundfield_render(self):
        class FirstNameForm(Form):
            first_name = CharField()
            template_name_label = "forms_tests/cyclic_context_boundfield_render.html"

        f = FirstNameForm()
        try:
            f.render()
        except RecursionError:
            self.fail("Cyclic reference in BoundField.render().")

    def test_legend_tag(self):
        class CustomFrameworkForm(FrameworkForm):
            template_name = "forms_tests/legend_test.html"
            required_css_class = "required"

        f = CustomFrameworkForm()
        self.assertHTMLEqual(
            str(f),
            '<label for="id_name" class="required">Name:</label>'
            '<legend class="required">Language:</legend>',
        )


class BoundFieldWithoutColon(BoundField):
    def label_tag(self, contents=None, attrs=None, label_suffix=None, tag=None):
        return super().label_tag(
            contents=contents, attrs=attrs, label_suffix="", tag=None
        )


class BoundFieldWithTwoColons(BoundField):
    def label_tag(self, contents=None, attrs=None, label_suffix=None, tag=None):
        return super().label_tag(
            contents=contents, attrs=attrs, label_suffix="::", tag=None
        )


class BoundFieldWithCustomClass(BoundField):
    def label_tag(self, contents=None, attrs=None, label_suffix=None, tag=None):
        attrs = attrs or {}
        attrs["class"] = "custom-class"
        return super().label_tag(contents, attrs, label_suffix, tag)


class BoundFieldWithWrappingClass(BoundField):
    def css_classes(self, extra_classes=None):
        parent_classes = super().css_classes(extra_classes)
        return f"field-class {parent_classes}"


class BoundFieldOverrideRenderer(DjangoTemplates):
    bound_field_class = BoundFieldWithoutColon


@override_settings(
    FORM_RENDERER="forms_tests.tests.test_forms.BoundFieldOverrideRenderer"
)
class CustomBoundFieldTest(SimpleTestCase):
    def test_renderer_custom_bound_field(self):
        t = Template("{{ form }}")
        html = t.render(Context({"form": Person()}))
        expected = """
            <div><label for="id_first_name">First name</label>
            <input type="text" name="first_name" required
            id="id_first_name"></div>
            <div><label for="id_last_name">Last name</label>
            <input type="text" name="last_name" required
            id="id_last_name"></div><div>
            <label for="id_birthday">Birthday</label>
            <input type="text" name="birthday" required
            id="id_birthday"></div>"""
        self.assertHTMLEqual(html, expected)

    def test_form_custom_boundfield(self):
        class CustomBoundFieldPerson(Person):
            bound_field_class = BoundFieldWithTwoColons

        with self.subTest("form's BoundField takes over renderer's BoundField"):
            t = Template("{{ form }}")
            html = t.render(Context({"form": CustomBoundFieldPerson()}))
            expected = """
                <div><label for="id_first_name">First name::</label>
                <input type="text" name="first_name" required
                id="id_first_name"></div>
                <div><label for="id_last_name">Last name::</label>
                <input type="text" name="last_name" required
                id="id_last_name"></div><div>
                <label for="id_birthday">Birthday::</label>
                <input type="text" name="birthday" required
                id="id_birthday"></div>"""
            self.assertHTMLEqual(html, expected)

        with self.subTest("Constructor argument takes over class property"):
            t = Template("{{ form }}")
            html = t.render(
                Context(
                    {
                        "form": CustomBoundFieldPerson(
                            bound_field_class=BoundFieldWithCustomClass
                        )
                    }
                )
            )
            expected = """
                <div><label class="custom-class" for="id_first_name">First name:</label>
                <input type="text" name="first_name" required
                id="id_first_name"></div>
                <div><label class="custom-class" for="id_last_name">Last name:</label>
                <input type="text" name="last_name" required
                id="id_last_name"></div><div>
                <label class="custom-class" for="id_birthday">Birthday:</label>
                <input type="text" name="birthday" required
                id="id_birthday"></div>"""
            self.assertHTMLEqual(html, expected)

        with self.subTest("Overriding css_classes works as expected"):
            t = Template("{{ form }}")
            html = t.render(
                Context(
                    {
                        "form": CustomBoundFieldPerson(
                            bound_field_class=BoundFieldWithWrappingClass
                        )
                    }
                )
            )
            expected = """
                <div class="field-class"><label for="id_first_name">First name:</label>
                <input type="text" name="first_name" required
                id="id_first_name"></div>
                <div class="field-class"><label for="id_last_name">Last name:</label>
                <input type="text" name="last_name" required
                id="id_last_name"></div><div class="field-class">
                <label for="id_birthday">Birthday:</label>
                <input type="text" name="birthday" required
                id="id_birthday"></div>"""
            self.assertHTMLEqual(html, expected)

    def test_field_custom_bound_field(self):
        class BoundFieldWithTwoColonsCharField(CharField):
            bound_field_class = BoundFieldWithTwoColons

        class CustomFieldBoundFieldPerson(Person):
            bound_field_class = BoundField

            first_name = BoundFieldWithTwoColonsCharField()
            last_name = BoundFieldWithTwoColonsCharField(
                bound_field_class=BoundFieldWithCustomClass
            )

        html = Template("{{ form }}").render(
            Context({"form": CustomFieldBoundFieldPerson()})
        )
        expected = """
            <div><label for="id_first_name">First name::</label>
            <input type="text" name="first_name" required
            id="id_first_name"></div>
            <div><label class="custom-class" for="id_last_name">Last name:</label>
            <input type="text" name="last_name" required
            id="id_last_name"></div><div>
            <label for="id_birthday">Birthday:</label>
            <input type="text" name="birthday" required
            id="id_birthday"></div>"""
        self.assertHTMLEqual(html, expected)
