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, CharField, CheckboxSelectMultiple, ChoiceField, DateField,
    DateTimeField, EmailField, FileField, FileInput, FloatField, Form,
    HiddenInput, ImageField, IntegerField, MultipleChoiceField,
    MultipleHiddenInput, MultiValueField, NullBooleanField, PasswordInput,
    RadioSelect, Select, SplitDateTimeField, SplitHiddenDateTimeWidget,
    Textarea, TextInput, TimeField, ValidationError, forms,
)
from django.forms.renderers import DjangoTemplates, get_default_renderer
from django.forms.utils import ErrorList
from django.http import QueryDict
from django.template import Context, Template
from django.test import SimpleTestCase
from django.utils.datastructures import MultiValueDict
from django.utils.safestring import mark_safe


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 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.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),
            """<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>
<tr><th><label for="id_last_name">Last name:</label></th><td>
<input type="text" name="last_name" value="Lennon" id="id_last_name" required></td></tr>
<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>"""
        )

    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),
            """<tr><th><label for="id_first_name">First name:</label></th><td>
<ul class="errorlist"><li>This field is required.</li></ul>
<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><ul class="errorlist"><li>This field is required.</li></ul>
<input type="text" name="last_name" id="id_last_name" required></td></tr>
<tr><th><label for="id_birthday">Birthday:</label></th><td>
<ul class="errorlist"><li>This field is required.</li></ul>
<input type="text" name="birthday" id="id_birthday" required></td></tr>"""
        )
        self.assertHTMLEqual(
            p.as_table(),
            """<tr><th><label for="id_first_name">First name:</label></th><td>
<ul class="errorlist"><li>This field is required.</li></ul>
<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><ul class="errorlist"><li>This field is required.</li></ul>
<input type="text" name="last_name" id="id_last_name" required></td></tr>
<tr><th><label for="id_birthday">Birthday:</label></th>
<td><ul class="errorlist"><li>This field is required.</li></ul>
<input type="text" name="birthday" id="id_birthday" required></td></tr>"""
        )
        self.assertHTMLEqual(
            p.as_ul(),
            """<li><ul class="errorlist"><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" required></li>
<li><ul class="errorlist"><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" required></li>
<li><ul class="errorlist"><li>This field is required.</li></ul>
<label for="id_birthday">Birthday:</label>
<input type="text" name="birthday" id="id_birthday" required></li>"""
        )
        self.assertHTMLEqual(
            p.as_p(),
            """<ul class="errorlist"><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" required></p>
<ul class="errorlist"><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" required></p>
<ul class="errorlist"><li>This field is required.</li></ul>
<p><label for="id_birthday">Birthday:</label>
<input type="text" name="birthday" id="id_birthday" required></p>"""
        )

    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),
            """<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_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>"""
        )

    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>'
        )

        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"><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>"""
        )

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

        f = FrameworkForm(auto_id=False)
        self.assertHTMLEqual(str(f['language']), """<ul>
<li><label><input type="radio" name="language" value="P" required> Python</label></li>
<li><label><input type="radio" name="language" value="J" required> Java</label></li>
</ul>""")
        self.assertHTMLEqual(f.as_table(), """<tr><th>Name:</th><td><input type="text" name="name" required></td></tr>
<tr><th>Language:</th><td><ul>
<li><label><input type="radio" name="language" value="P" required> Python</label></li>
<li><label><input type="radio" name="language" value="J" required> Java</label></li>
</ul></td></tr>""")
        self.assertHTMLEqual(f.as_ul(), """<li>Name: <input type="text" name="name" required></li>
<li>Language: <ul>
<li><label><input type="radio" name="language" value="P" required> Python</label></li>
<li><label><input type="radio" name="language" value="J" required> Java</label></li>
</ul></li>""")

        # 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']),
            """<ul id="id_language">
<li><label for="id_language_0"><input type="radio" id="id_language_0" value="P" name="language" required>
Python</label></li>
<li><label for="id_language_1"><input type="radio" id="id_language_1" value="J" name="language" required>
Java</label></li>
</ul>"""
        )

        # 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 point to the
        # ID of the *first* radio button.
        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 for="id_language_0">Language:</label></th><td><ul id="id_language">
<li><label for="id_language_0"><input type="radio" id="id_language_0" value="P" name="language" required>
Python</label></li>
<li><label for="id_language_1"><input type="radio" id="id_language_1" value="J" name="language" required>
Java</label></li>
</ul></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 for="id_language_0">Language:</label> <ul id="id_language">
<li><label for="id_language_0"><input type="radio" id="id_language_0" value="P" name="language" required>
Python</label></li>
<li><label for="id_language_1"><input type="radio" id="id_language_1" value="J" name="language" required>
Java</label></li>
</ul></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 for="id_language_0">Language:</label> <ul id="id_language">
<li><label for="id_language_0"><input type="radio" id="id_language_0" value="P" name="language" required>
Python</label></li>
<li><label for="id_language_1"><input type="radio" id="id_language_1" value="J" name="language" required>
Java</label></li>
</ul></p>"""
        )

        # Test iterating on individual radios in a template
        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_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.assertEqual(fields[0].id_for_label, 'id_name_0')
        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>""")

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

        f = SongForm(auto_id=False)
        self.assertHTMLEqual(str(f['composers']), """<ul>
<li><label><input type="checkbox" name="composers" value="J"> John Lennon</label></li>
<li><label><input type="checkbox" name="composers" value="P"> Paul McCartney</label></li>
</ul>""")
        f = SongForm({'composers': ['J']}, auto_id=False)
        self.assertHTMLEqual(str(f['composers']), """<ul>
<li><label><input checked type="checkbox" name="composers" value="J"> John Lennon</label></li>
<li><label><input type="checkbox" name="composers" value="P"> Paul McCartney</label></li>
</ul>""")
        f = SongForm({'composers': ['J', 'P']}, auto_id=False)
        self.assertHTMLEqual(str(f['composers']), """<ul>
<li><label><input checked type="checkbox" name="composers" value="J"> John Lennon</label></li>
<li><label><input checked type="checkbox" name="composers" value="P"> Paul McCartney</label></li>
</ul>""")
        # Test iterating on individual checkboxes in a template
        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_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']),
            """<ul id="composers_id">
<li><label for="composers_id_0">
<input type="checkbox" name="composers" value="J" id="composers_id_0"> John Lennon</label></li>
<li><label for="composers_id_1">
<input type="checkbox" name="composers" value="P" id="composers_id_1"> Paul McCartney</label></li>
</ul>"""
        )

    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" 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" 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;" 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;" 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" required></td></tr>
<tr><th>Password1:</th><td><ul class="errorlist"><li>This field is required.</li></ul>
<input type="password" name="password1" required></td></tr>
<tr><th>Password2:</th><td><ul class="errorlist"><li>This field is required.</li></ul>
<input type="password" name="password2" 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>"""
        )

        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': forms.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, forms.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)

    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>"""
        )

        # 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>"""
        )

        # 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>"""
        )

        # 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_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(), """<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>
<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>
<tr><th>Field5:</th><td><input type="text" name="field5" required></td></tr>
<tr><th>Field6:</th><td><input type="text" name="field6" required></td></tr>
<tr><th>Field7:</th><td><input type="text" name="field7" required></td></tr>
<tr><th>Field8:</th><td><input type="text" name="field8" required></td></tr>
<tr><th>Field9:</th><td><input type="text" name="field9" required></td></tr>
<tr><th>Field10:</th><td><input type="text" name="field10" required></td></tr>
<tr><th>Field11:</th><td><input type="text" name="field11" required></td></tr>
<tr><th>Field12:</th><td><input type="text" name="field12" required></td></tr>
<tr><th>Field13:</th><td><input type="text" name="field13" required></td></tr>
<tr><th>Field14:</th><td><input type="text" name="field14" required></td></tr>""")

    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" required></li>
<li><ul class="errorlist"><li>This field is required.</li></ul>
Password: <input type="password" name="password" 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" required></li>
<li><ul class="errorlist"><li>This field is required.</li></ul>
Password: <input type="password" name="password" 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" 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" required></li>
<li><ul class="errorlist"><li>This field is required.</li></ul>
Password: <input type="password" name="password" 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" required></li>
<li><ul class="errorlist"><li>This field is required.</li></ul>
Password: <input type="password" name="password" 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" 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" required></li>
<li><ul class="errorlist"><li>This field is required.</li></ul>
Password: <input type="password" name="password" required></li>
<li><ul class="errorlist"><li>This field is required.</li></ul>
Options: <select multiple name="options" 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" required></li>
<li><ul class="errorlist"><li>This field is required.</li></ul>
Password: <input type="password" name="password" required></li>
<li><ul class="errorlist"><li>This field is required.</li></ul>
Options: <select multiple name="options" 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" 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):
        class PersonForm(Form):
            first_name = CharField(initial='John')
            last_name = CharField(initial='Doe')
            age = IntegerField()
            occupation = CharField(initial=lambda: 'Unknown')

        form = PersonForm(initial={'first_name': 'Jane'})
        self.assertIsNone(form.get_initial_for_field(form.fields['age'], 'age'))
        self.assertEqual(form.get_initial_for_field(form.fields['last_name'], 'last_name'), 'Doe')
        # Form.initial overrides Field.initial.
        self.assertEqual(form.get_initial_for_field(form.fields['first_name'], 'first_name'), 'Jane')
        # Callables are evaluated.
        self.assertEqual(form.get_initial_for_field(form.fields['occupation'], 'occupation'), 'Unknown')

    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(forms.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):
            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()
        self.assertEqual(unbound['auto_timestamp'].value(), now_no_ms)
        self.assertEqual(unbound['auto_time_only'].value(), now_no_ms.time())
        self.assertEqual(unbound['supports_microseconds'].value(), now)
        self.assertEqual(unbound['hi_default_microsec'].value(), now)
        self.assertEqual(unbound['hi_without_microsec'].value(), now_no_ms)
        self.assertEqual(unbound['ti_without_microsec'].value(), now_no_ms)

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

        class DateTimeForm(forms.Form):
            dt = DateTimeField(initial=lambda: now, disabled=True)

        form = DateTimeForm({})
        self.assertEqual(form.errors, {})
        self.assertEqual(form.cleaned_data, {'dt': now})

    def test_datetime_changed_data_callable_with_microseconds(self):
        class DateTimeForm(forms.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>"""
        )

        # 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" 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_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" 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" 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" 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(forms.Form):
            file1 = forms.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 = forms.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_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">\n'
                '<table>\n{{ form }}\n</table>\n<input type="submit" required>\n</form>'
            )
            return t.render(Context({'form': form}))

        # Case 1: GET (an empty form, with no errors).)
        self.assertHTMLEqual(my_function('GET', {}), """<form method="post">
<table>
<tr><th>Username:</th><td><input type="text" name="username" 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>
</table>
<input type="submit" required>
</form>""")
        # Case 2: 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">
<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><ul class="errorlist">
<li>Ensure this value has at most 10 characters (it has 23).</li></ul>
<input type="text" name="username" value="this-is-a-long-username" 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>
</table>
<input type="submit" required>
</form>"""
        )
        # Case 3: 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_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

        # You have 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. Note, however, that 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>''')
        self.assertHTMLEqual(t.render(Context({'form': UserRegistration(auto_id=False)})), """<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>""")
        self.assertHTMLEqual(
            t.render(Context({'form': UserRegistration({'username': 'django'}, auto_id=False)})),
            """<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" required></label></p>
<ul class="errorlist"><li>This field is required.</li></ul>
<p><label>Password (again): <input type="password" name="password2" required></label></p>
<input type="submit" required>
</form>"""
        )

        # Use form.[field].label to output a field's label. 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.
        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>''')
        self.assertHTMLEqual(t.render(Context({'form': UserRegistration(auto_id=False)})), """<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>""")

        # User 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 }}</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': UserRegistration(auto_id=False)})), """<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>""")
        self.assertHTMLEqual(t.render(Context({'form': UserRegistration(auto_id='id_%s')})), """<form>
<p><label for="id_username">Username:</label>
<input id="id_username" type="text" name="username" maxlength="10" required></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>""")

        # User 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>''')
        self.assertHTMLEqual(
            t.render(Context({'form': UserRegistration(auto_id=False)})),
            """<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': UserRegistration(auto_id=False)})),
            ''
        )

        # 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). You can also use it in {% if %} statements.
        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>''')
        self.assertHTMLEqual(
            t.render(Context({
                'form': UserRegistration({'username': 'django', 'password1': 'foo', 'password2': 'bar'}, auto_id=False)
            })),
            """<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': UserRegistration({'username': 'django', 'password1': 'foo', 'password2': 'bar'}, auto_id=False)
            })),
            """<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_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"><li>This field is required.</li></ul>
<label class="required" for="id_name">Name:</label> <input type="text" name="name" id="id_name" required></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"></li>
<li class="required error"><ul class="errorlist"><li>This field is required.</li></ul>
<label class="required" for="id_age">Age:</label> <input type="number" name="age" id="id_age" required></li>"""
        )

        self.assertHTMLEqual(
            p.as_p(),
            """<ul class="errorlist"><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" required></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"></p>
<ul class="errorlist"><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" required></p>"""
        )

        self.assertHTMLEqual(
            p.as_table(),
            """<tr class="required error">
<th><label class="required" for="id_name">Name:</label></th>
<td><ul class="errorlist"><li>This field is required.</li></ul>
<input type="text" name="name" id="id_name" required></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"></td></tr>
<tr class="required error"><th><label class="required" for="id_age">Age:</label></th>
<td><ul class="errorlist"><li>This field is required.</li></ul>
<input type="number" name="age" id="id_age" required></td></tr>"""
        )

    def test_label_has_required_css_class(self):
        """
        #17922 - required_css_class is added to the label_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'].label_tag(attrs={'class': 'foo'}),
            '<label for="id_field" class="foo required">Field:</label>'
        )
        self.assertHTMLEqual(f['field2'].label_tag(), '<label for="id_field2">Field2:</label>')

    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_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(forms.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>
            ((), {}, '<label for="id_field">Field:</label>'),

            # passing just one argument: overrides the field's label
            (('custom',), {}, '<label for="id_field">custom:</label>'),

            # the overridden label is escaped
            (('custom&',), {}, '<label for="id_field">custom&amp;:</label>'),
            ((mark_safe('custom&'),), {}, '<label for="id_field">custom&:</label>'),

            # Passing attrs to add extra attributes on the <label>
            ((), {'attrs': {'class': 'pretty'}}, '<label for="id_field" class="pretty">Field:</label>')
        ]

        for args, kwargs, expected in testcases:
            with self.subTest(args=args, kwargs=kwargs):
                self.assertHTMLEqual(boundfield.label_tag(*args, **kwargs), expected)

    def test_boundfield_label_tag_no_id(self):
        """
        If a widget has no id, label_tag just returns 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.label_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['empty'].label_tag(), '<label>Empty:</label>')

    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>')

    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_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_tag_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>')

    def test_field_name(self):
        """#5749 - `field_name` may be used as a key in _html_output()."""
        class SomeForm(Form):
            some_field = CharField()

            def as_p(self):
                return self._html_output(
                    normal_row='<p id="p_%(field_name)s"></p>',
                    error_row='%s',
                    row_ender='</p>',
                    help_text_html=' %s',
                    errors_on_separate_row=True,
                )

        form = SomeForm()
        self.assertHTMLEqual(form.as_p(), '<p id="p_some_field"></p>')

    def test_field_without_css_classes(self):
        """
        `css_classes` may be used as a key in _html_output() (empty classes).
        """
        class SomeForm(Form):
            some_field = CharField()

            def as_p(self):
                return self._html_output(
                    normal_row='<p class="%(css_classes)s"></p>',
                    error_row='%s',
                    row_ender='</p>',
                    help_text_html=' %s',
                    errors_on_separate_row=True,
                )

        form = SomeForm()
        self.assertHTMLEqual(form.as_p(), '<p class=""></p>')

    def test_field_with_css_class(self):
        """
        `css_classes` may be used as a key in _html_output() (class comes
        from required_css_class in this case).
        """
        class SomeForm(Form):
            some_field = CharField()
            required_css_class = 'foo'

            def as_p(self):
                return self._html_output(
                    normal_row='<p class="%(css_classes)s"></p>',
                    error_row='%s',
                    row_ender='</p>',
                    help_text_html=' %s',
                    errors_on_separate_row=True,
                )

        form = SomeForm()
        self.assertHTMLEqual(form.as_p(), '<p class="foo"></p>')

    def test_field_name_with_hidden_input(self):
        """
        BaseForm._html_output() should merge all the hidden input fields and
        put them in the last row.
        """
        class SomeForm(Form):
            hidden1 = CharField(widget=HiddenInput)
            custom = CharField()
            hidden2 = CharField(widget=HiddenInput)

            def as_p(self):
                return self._html_output(
                    normal_row='<p%(html_class_attr)s>%(field)s %(field_name)s</p>',
                    error_row='%s',
                    row_ender='</p>',
                    help_text_html=' %s',
                    errors_on_separate_row=True,
                )

        form = SomeForm()
        self.assertHTMLEqual(
            form.as_p(),
            '<p><input id="id_custom" name="custom" type="text" required> custom'
            '<input id="id_hidden1" name="hidden1" type="hidden">'
            '<input id="id_hidden2" name="hidden2" type="hidden"></p>'
        )

    def test_field_name_with_hidden_input_and_non_matching_row_ender(self):
        """
        BaseForm._html_output() should merge all the hidden input fields and
        put them in the last row ended with the specific row ender.
        """
        class SomeForm(Form):
            hidden1 = CharField(widget=HiddenInput)
            custom = CharField()
            hidden2 = CharField(widget=HiddenInput)

            def as_p(self):
                return self._html_output(
                    normal_row='<p%(html_class_attr)s>%(field)s %(field_name)s</p>',
                    error_row='%s',
                    row_ender='<hr><hr>',
                    help_text_html=' %s',
                    errors_on_separate_row=True
                )

        form = SomeForm()
        self.assertHTMLEqual(
            form.as_p(),
            '<p><input id="id_custom" name="custom" type="text" required> custom</p>\n'
            '<input id="id_hidden1" name="hidden1" type="hidden">'
            '<input id="id_hidden2" name="hidden2" type="hidden"><hr><hr>'
        )

    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"><li>This field is required.</li></ul></li>',
            '<li>bar<ul class="errorlist"><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>"""
        )

    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>"""
        )

    def test_errorlist_override(self):
        class DivErrorList(ErrorList):
            def __str__(self):
                return self.as_divs()

            def as_divs(self):
                if not self:
                    return ''
                return '<div class="errorlist">%s</div>' % ''.join(
                    '<div class="error">%s</div>' % e for e in self)

        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=DivErrorList)
        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" required></p>
<div class="errorlist"><div class="error">This field is required.</div></div>
<p>Comment: <input type="text" name="comment" required></p>""")

    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"><li>Foo &amp; &quot;bar&quot;!</li></ul>'
            '<label for="id_visible">Visible:</label> '
            '<input type="text" name="visible" value="b" id="id_visible" required>'
            '<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>',
        )

    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>',
        )

    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)


class CustomRenderer(DjangoTemplates):
    pass


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)
