text: from __future__ import unicode_literals
  
  import datetime
  import os
  from decimal import Decimal
  from unittest import skipUnless
  
  from django import forms
  from django.core.exceptions import (
      NON_FIELD_ERRORS, FieldError, ImproperlyConfigured,
  )
  from django.core.files.uploadedfile import SimpleUploadedFile
  from django.core.validators import ValidationError
  from django.db import connection, models
  from django.db.models.query import EmptyQuerySet
  from django.forms.models import (
      ModelChoiceIterator, ModelFormMetaclass, construct_instance,
      fields_for_model, model_to_dict, modelform_factory,
  )
  from django.template import Context, Template
  from django.test import SimpleTestCase, TestCase, skipUnlessDBFeature
  from django.utils import six
  from django.utils._os import upath
  
  from .models import (
      Article, ArticleStatus, Author, Author1, Award, BetterWriter, BigInt, Book,
      Category, Character, Colour, ColourfulItem, CommaSeparatedInteger,
      CustomErrorMessage, CustomFF, CustomFieldForExclusionModel, DateTimePost,
      DerivedBook, DerivedPost, Document, ExplicitPK, FilePathModel,
      FlexibleDatePost, Homepage, ImprovedArticle, ImprovedArticleWithParentLink,
      Inventory, NullableUniqueCharFieldModel, Person, Photo, Post, Price,
      Product, Publication, PublicationDefaults, StrictAssignmentAll,
      StrictAssignmentFieldSpecific, Student, StumpJoke, TextFile, Triple,
      Writer, WriterProfile, test_images,
  )
  
  if test_images:
      from .models import ImageFile, OptionalImageFile
  
      class ImageFileForm(forms.ModelForm):
          class Meta:
              model = ImageFile
              fields = '__all__'
  
      class OptionalImageFileForm(forms.ModelForm):
          class Meta:
              model = OptionalImageFile
              fields = '__all__'
  
  
  class ProductForm(forms.ModelForm):
      class Meta:
          model = Product
          fields = '__all__'
  
  
  class PriceForm(forms.ModelForm):
      class Meta:
          model = Price
          fields = '__all__'
  
  
  class BookForm(forms.ModelForm):
      class Meta:
          model = Book
          fields = '__all__'
  
  
  class DerivedBookForm(forms.ModelForm):
      class Meta:
          model = DerivedBook
          fields = '__all__'
  
  
  class ExplicitPKForm(forms.ModelForm):
      class Meta:
          model = ExplicitPK
          fields = ('key', 'desc',)
  
  
  class PostForm(forms.ModelForm):
      class Meta:
          model = Post
          fields = '__all__'
  
  
  class DerivedPostForm(forms.ModelForm):
      class Meta:
          model = DerivedPost
          fields = '__all__'
  
  
  class CustomWriterForm(forms.ModelForm):
      name = forms.CharField(required=False)
  
      class Meta:
          model = Writer
          fields = '__all__'
  
  
  class BaseCategoryForm(forms.ModelForm):
      class Meta:
          model = Category
          fields = '__all__'
  
  
  class ArticleForm(forms.ModelForm):
      class Meta:
          model = Article
          fields = '__all__'
  
  
  class RoykoForm(forms.ModelForm):
      class Meta:
          model = Writer
          fields = '__all__'
  
  
  class ArticleStatusForm(forms.ModelForm):
      class Meta:
          model = ArticleStatus
          fields = '__all__'
  
  
  class InventoryForm(forms.ModelForm):
      class Meta:
          model = Inventory
          fields = '__all__'
  
  
  class SelectInventoryForm(forms.Form):
      items = forms.ModelMultipleChoiceField(Inventory.objects.all(), to_field_name='barcode')
  
  
  class CustomFieldForExclusionForm(forms.ModelForm):
      class Meta:
          model = CustomFieldForExclusionModel
          fields = ['name', 'markup']
  
  
  class TextFileForm(forms.ModelForm):
      class Meta:
          model = TextFile
          fields = '__all__'
  
  
  class BigIntForm(forms.ModelForm):
      class Meta:
          model = BigInt
          fields = '__all__'
  
  
  class ModelFormWithMedia(forms.ModelForm):
      class Media:
          js = ('/some/form/javascript',)
          css = {
              'all': ('/some/form/css',)
          }
  
      class Meta:
          model = TextFile
          fields = '__all__'
  
  
  class CustomErrorMessageForm(forms.ModelForm):
      name1 = forms.CharField(error_messages={'invalid': 'Form custom error message.'})
  
      class Meta:
          fields = '__all__'
          model = CustomErrorMessage
  
  
  class ModelFormBaseTest(TestCase):
      def test_base_form(self):
          self.assertEqual(list(BaseCategoryForm.base_fields),
                           ['name', 'slug', 'url'])
  
      def test_no_model_class(self):
          class NoModelModelForm(forms.ModelForm):
              pass
          with self.assertRaises(ValueError):
              NoModelModelForm()
  
      def test_empty_fields_to_fields_for_model(self):
          """
          An argument of fields=() to fields_for_model should return an empty dictionary
          """
          field_dict = fields_for_model(Person, fields=())
          self.assertEqual(len(field_dict), 0)
  
      def test_empty_fields_on_modelform(self):
          """
          No fields on a ModelForm should actually result in no fields.
          """
          class EmptyPersonForm(forms.ModelForm):
              class Meta:
                  model = Person
                  fields = ()
  
          form = EmptyPersonForm()
          self.assertEqual(len(form.fields), 0)
  
      def test_empty_fields_to_construct_instance(self):
          """
          No fields should be set on a model instance if construct_instance receives fields=().
          """
          form = modelform_factory(Person, fields="__all__")({'name': 'John Doe'})
          self.assertTrue(form.is_valid())
          instance = construct_instance(form, Person(), fields=())
          self.assertEqual(instance.name, '')
  
      def test_blank_with_null_foreign_key_field(self):
          """
          #13776 -- ModelForm's with models having a FK set to null=False and
          required=False should be valid.
          """
          class FormForTestingIsValid(forms.ModelForm):
              class Meta:
                  model = Student
                  fields = '__all__'
  
              def __init__(self, *args, **kwargs):
                  super(FormForTestingIsValid, self).__init__(*args, **kwargs)
                  self.fields['character'].required = False
  
          char = Character.objects.create(username='user',
                                          last_action=datetime.datetime.today())
          data = {'study': 'Engineering'}
          data2 = {'study': 'Engineering', 'character': char.pk}
  
          # form is valid because required=False for field 'character'
          f1 = FormForTestingIsValid(data)
          self.assertTrue(f1.is_valid())
  
          f2 = FormForTestingIsValid(data2)
          self.assertTrue(f2.is_valid())
          obj = f2.save()
          self.assertEqual(obj.character, char)
  
      def test_blank_false_with_null_true_foreign_key_field(self):
          """
          A ModelForm with a model having ForeignKey(blank=False, null=True)
          and the form field set to required=False should allow the field to be
          unset.
          """
          class AwardForm(forms.ModelForm):
              class Meta:
                  model = Award
                  fields = '__all__'
  
              def __init__(self, *args, **kwargs):
                  super(AwardForm, self).__init__(*args, **kwargs)
                  self.fields['character'].required = False
  
          character = Character.objects.create(username='user', last_action=datetime.datetime.today())
          award = Award.objects.create(name='Best sprinter', character=character)
          data = {'name': 'Best tester', 'character': ''}  # remove character
          form = AwardForm(data=data, instance=award)
          self.assertTrue(form.is_valid())
          award = form.save()
          self.assertIsNone(award.character)
  
      def test_save_blank_false_with_required_false(self):
          """
          A ModelForm with a model with a field set to blank=False and the form
          field set to required=False should allow the field to be unset.
          """
          obj = Writer.objects.create(name='test')
          form = CustomWriterForm(data={'name': ''}, instance=obj)
          self.assertTrue(form.is_valid())
          obj = form.save()
          self.assertEqual(obj.name, '')
  
      def test_save_blank_null_unique_charfield_saves_null(self):
          form_class = modelform_factory(model=NullableUniqueCharFieldModel, fields=['codename'])
          empty_value = '' if connection.features.interprets_empty_strings_as_nulls else None
  
          form = form_class(data={'codename': ''})
          self.assertTrue(form.is_valid())
          form.save()
          self.assertEqual(form.instance.codename, empty_value)
  
          # Save a second form to verify there isn't a unique constraint violation.
          form = form_class(data={'codename': ''})
          self.assertTrue(form.is_valid())
          form.save()
          self.assertEqual(form.instance.codename, empty_value)
  
      def test_missing_fields_attribute(self):
          message = (
              "Creating a ModelForm without either the 'fields' attribute "
              "or the 'exclude' attribute is prohibited; form "
              "MissingFieldsForm needs updating."
          )
          with self.assertRaisesMessage(ImproperlyConfigured, message):
              class MissingFieldsForm(forms.ModelForm):
                  class Meta:
                      model = Category
  
      def test_extra_fields(self):
          class ExtraFields(BaseCategoryForm):
              some_extra_field = forms.BooleanField()
  
          self.assertEqual(list(ExtraFields.base_fields),
                           ['name', 'slug', 'url', 'some_extra_field'])
  
      def test_extra_field_model_form(self):
          with self.assertRaisesMessage(FieldError, 'no-field'):
              class ExtraPersonForm(forms.ModelForm):
                  """ ModelForm with an extra field """
                  age = forms.IntegerField()
  
                  class Meta:
                      model = Person
                      fields = ('name', 'no-field')
  
      def test_extra_declared_field_model_form(self):
          class ExtraPersonForm(forms.ModelForm):
              """ ModelForm with an extra field """
              age = forms.IntegerField()
  
              class Meta:
                  model = Person
                  fields = ('name', 'age')
  
      def test_extra_field_modelform_factory(self):
          with self.assertRaises(FieldError):
              modelform_factory(Person, fields=['no-field', 'name'])
  
      def test_replace_field(self):
          class ReplaceField(forms.ModelForm):
              url = forms.BooleanField()
  
              class Meta:
                  model = Category
                  fields = '__all__'
  
          self.assertIsInstance(ReplaceField.base_fields['url'], forms.fields.BooleanField)
  
      def test_replace_field_variant_2(self):
          # Should have the same result as before,
          # but 'fields' attribute specified differently
          class ReplaceField(forms.ModelForm):
              url = forms.BooleanField()
  
              class Meta:
                  model = Category
                  fields = ['url']
  
          self.assertIsInstance(ReplaceField.base_fields['url'], forms.fields.BooleanField)
  
      def test_replace_field_variant_3(self):
          # Should have the same result as before,
          # but 'fields' attribute specified differently
          class ReplaceField(forms.ModelForm):
              url = forms.BooleanField()
  
              class Meta:
                  model = Category
                  fields = []  # url will still appear, since it is explicit above
  
          self.assertIsInstance(ReplaceField.base_fields['url'], forms.fields.BooleanField)
  
      def test_override_field(self):
          class WriterForm(forms.ModelForm):
              book = forms.CharField(required=False)
  
              class Meta:
                  model = Writer
                  fields = '__all__'
  
          wf = WriterForm({'name': 'Richard Lockridge'})
          self.assertTrue(wf.is_valid())
  
      def test_limit_nonexistent_field(self):
          expected_msg = 'Unknown field(s) (nonexistent) specified for Category'
          with self.assertRaisesMessage(FieldError, expected_msg):
              class InvalidCategoryForm(forms.ModelForm):
                  class Meta:
                      model = Category
                      fields = ['nonexistent']
  
      def test_limit_fields_with_string(self):
          expected_msg = "CategoryForm.Meta.fields cannot be a string. Did you mean to type: ('url',)?"
          with self.assertRaisesMessage(TypeError, expected_msg):
              class CategoryForm(forms.ModelForm):
                  class Meta:
                      model = Category
                      fields = ('url')  # note the missing comma
  
      def test_exclude_fields(self):
          class ExcludeFields(forms.ModelForm):
              class Meta:
                  model = Category
                  exclude = ['url']
  
          self.assertEqual(list(ExcludeFields.base_fields), ['name', 'slug'])
  
      def test_exclude_nonexistent_field(self):
          class ExcludeFields(forms.ModelForm):
              class Meta:
                  model = Category
                  exclude = ['nonexistent']
  
          self.assertEqual(list(ExcludeFields.base_fields), ['name', 'slug', 'url'])
  
      def test_exclude_fields_with_string(self):
          expected_msg = "CategoryForm.Meta.exclude cannot be a string. Did you mean to type: ('url',)?"
          with self.assertRaisesMessage(TypeError, expected_msg):
              class CategoryForm(forms.ModelForm):
                  class Meta:
                      model = Category
                      exclude = ('url')  # note the missing comma
  
      def test_exclude_and_validation(self):
          # This Price instance generated by this form is not valid because the quantity
          # field is required, but the form is valid because the field is excluded from
          # the form. This is for backwards compatibility.
          class PriceFormWithoutQuantity(forms.ModelForm):
              class Meta:
                  model = Price
                  exclude = ('quantity',)
  
          form = PriceFormWithoutQuantity({'price': '6.00'})
          self.assertTrue(form.is_valid())
          price = form.save(commit=False)
          with self.assertRaises(ValidationError):
              price.full_clean()
  
          # The form should not validate fields that it doesn't contain even if they are
          # specified using 'fields', not 'exclude'.
          class PriceFormWithoutQuantity(forms.ModelForm):
              class Meta:
                  model = Price
                  fields = ('price',)
          form = PriceFormWithoutQuantity({'price': '6.00'})
          self.assertTrue(form.is_valid())
  
          # The form should still have an instance of a model that is not complete and
          # not saved into a DB yet.
          self.assertEqual(form.instance.price, Decimal('6.00'))
          self.assertIsNone(form.instance.quantity)
          self.assertIsNone(form.instance.pk)
  
      def test_confused_form(self):
          class ConfusedForm(forms.ModelForm):
              """ Using 'fields' *and* 'exclude'. Not sure why you'd want to do
              this, but uh, "be liberal in what you accept" and all.
              """
              class Meta:
                  model = Category
                  fields = ['name', 'url']
                  exclude = ['url']
  
          self.assertEqual(list(ConfusedForm.base_fields),
                           ['name'])
  
      def test_mixmodel_form(self):
          class MixModelForm(BaseCategoryForm):
              """ Don't allow more than one 'model' definition in the
              inheritance hierarchy.  Technically, it would generate a valid
              form, but the fact that the resulting save method won't deal with
              multiple objects is likely to trip up people not familiar with the
              mechanics.
              """
              class Meta:
                  model = Article
                  fields = '__all__'
              # MixModelForm is now an Article-related thing, because MixModelForm.Meta
              # overrides BaseCategoryForm.Meta.
  
          self.assertEqual(
              list(MixModelForm.base_fields),
              ['headline', 'slug', 'pub_date', 'writer', 'article', 'categories', 'status']
          )
  
      def test_article_form(self):
          self.assertEqual(
              list(ArticleForm.base_fields),
              ['headline', 'slug', 'pub_date', 'writer', 'article', 'categories', 'status']
          )
  
      def test_bad_form(self):
          # First class with a Meta class wins...
          class BadForm(ArticleForm, BaseCategoryForm):
              pass
  
          self.assertEqual(
              list(BadForm.base_fields),
              ['headline', 'slug', 'pub_date', 'writer', 'article', 'categories', 'status']
          )
  
      def test_invalid_meta_model(self):
          class InvalidModelForm(forms.ModelForm):
              class Meta:
                  pass  # no model
  
          # Can't create new form
          with self.assertRaises(ValueError):
              InvalidModelForm()
  
          # Even if you provide a model instance
          with self.assertRaises(ValueError):
              InvalidModelForm(instance=Category)
  
      def test_subcategory_form(self):
          class SubCategoryForm(BaseCategoryForm):
              """ Subclassing without specifying a Meta on the class will use
              the parent's Meta (or the first parent in the MRO if there are
              multiple parent classes).
              """
              pass
  
          self.assertEqual(list(SubCategoryForm.base_fields),
                           ['name', 'slug', 'url'])
  
      def test_subclassmeta_form(self):
          class SomeCategoryForm(forms.ModelForm):
              checkbox = forms.BooleanField()
  
              class Meta:
                  model = Category
                  fields = '__all__'
  
          class SubclassMeta(SomeCategoryForm):
              """ We can also subclass the Meta inner class to change the fields
              list.
              """
              class Meta(SomeCategoryForm.Meta):
                  exclude = ['url']
  
          self.assertHTMLEqual(
              str(SubclassMeta()),
              """<tr><th><label for="id_name">Name:</label></th>
  <td><input id="id_name" type="text" name="name" maxlength="20" required /></td></tr>
  <tr><th><label for="id_slug">Slug:</label></th>
  <td><input id="id_slug" type="text" name="slug" maxlength="20" required /></td></tr>
  <tr><th><label for="id_checkbox">Checkbox:</label></th>
  <td><input type="checkbox" name="checkbox" id="id_checkbox" required /></td></tr>"""
          )
  
      def test_orderfields_form(self):
          class OrderFields(forms.ModelForm):
              class Meta:
                  model = Category
                  fields = ['url', 'name']
  
          self.assertEqual(list(OrderFields.base_fields),
                           ['url', 'name'])
          self.assertHTMLEqual(
              str(OrderFields()),
              """<tr><th><label for="id_url">The URL:</label></th>
  <td><input id="id_url" type="text" name="url" maxlength="40" required /></td></tr>
  <tr><th><label for="id_name">Name:</label></th>
  <td><input id="id_name" type="text" name="name" maxlength="20" required /></td></tr>"""
          )
  
      def test_orderfields2_form(self):
          class OrderFields2(forms.ModelForm):
              class Meta:
                  model = Category
                  fields = ['slug', 'url', 'name']
                  exclude = ['url']
  
          self.assertEqual(list(OrderFields2.base_fields),
                           ['slug', 'name'])
  
  
  class FieldOverridesByFormMetaForm(forms.ModelForm):
      class Meta:
          model = Category
          fields = ['name', 'url', 'slug']
          widgets = {
              'name': forms.Textarea,
              'url': forms.TextInput(attrs={'class': 'url'})
          }
          labels = {
              'name': 'Title',
          }
          help_texts = {
              'slug': 'Watch out! Letters, numbers, underscores and hyphens only.',
          }
          error_messages = {
              'slug': {
                  'invalid': (
                      "Didn't you read the help text? "
                      "We said letters, numbers, underscores and hyphens only!"
                  )
              }
          }
          field_classes = {
              'url': forms.URLField,
          }
  
  
  class TestFieldOverridesByFormMeta(SimpleTestCase):
      def test_widget_overrides(self):
          form = FieldOverridesByFormMetaForm()
          self.assertHTMLEqual(
              str(form['name']),
              '<textarea id="id_name" rows="10" cols="40" name="name" maxlength="20" required></textarea>',
          )
          self.assertHTMLEqual(
              str(form['url']),
              '<input id="id_url" type="text" class="url" name="url" maxlength="40" required />',
          )
          self.assertHTMLEqual(
              str(form['slug']),
              '<input id="id_slug" type="text" name="slug" maxlength="20" required />',
          )
  
      def test_label_overrides(self):
          form = FieldOverridesByFormMetaForm()
          self.assertHTMLEqual(
              str(form['name'].label_tag()),
              '<label for="id_name">Title:</label>',
          )
          self.assertHTMLEqual(
              str(form['url'].label_tag()),
              '<label for="id_url">The URL:</label>',
          )
          self.assertHTMLEqual(
              str(form['slug'].label_tag()),
              '<label for="id_slug">Slug:</label>',
          )
  
      def test_help_text_overrides(self):
          form = FieldOverridesByFormMetaForm()
          self.assertEqual(
              form['slug'].help_text,
              'Watch out! Letters, numbers, underscores and hyphens only.',
          )
  
      def test_error_messages_overrides(self):
          form = FieldOverridesByFormMetaForm(data={
              'name': 'Category',
              'url': 'http://www.example.com/category/',
              'slug': '!%#*@',
          })
          form.full_clean()
  
          error = [
              "Didn't you read the help text? "
              "We said letters, numbers, underscores and hyphens only!",
          ]
          self.assertEqual(form.errors, {'slug': error})
  
      def test_field_type_overrides(self):
          form = FieldOverridesByFormMetaForm()
          self.assertIs(Category._meta.get_field('url').__class__, models.CharField)
          self.assertIsInstance(form.fields['url'], forms.URLField)
  
  
  class IncompleteCategoryFormWithFields(forms.ModelForm):
      """
      A form that replaces the model's url field with a custom one. This should
      prevent the model field's validation from being called.
      """
      url = forms.CharField(required=False)
  
      class Meta:
          fields = ('name', 'slug')
          model = Category
  
  
  class IncompleteCategoryFormWithExclude(forms.ModelForm):
      """
      A form that replaces the model's url field with a custom one. This should
      prevent the model field's validation from being called.
      """
      url = forms.CharField(required=False)
  
      class Meta:
          exclude = ['url']
          model = Category
  
  
  class ValidationTest(SimpleTestCase):
      def test_validates_with_replaced_field_not_specified(self):
          form = IncompleteCategoryFormWithFields(data={'name': 'some name', 'slug': 'some-slug'})
          assert form.is_valid()
  
      def test_validates_with_replaced_field_excluded(self):
          form = IncompleteCategoryFormWithExclude(data={'name': 'some name', 'slug': 'some-slug'})
          assert form.is_valid()
  
      def test_notrequired_overrides_notblank(self):
          form = CustomWriterForm({})
          assert form.is_valid()
  
  
  class UniqueTest(TestCase):
      """
      unique/unique_together validation.
      """
      def setUp(self):
          self.writer = Writer.objects.create(name='Mike Royko')
  
      def test_simple_unique(self):
          form = ProductForm({'slug': 'teddy-bear-blue'})
          self.assertTrue(form.is_valid())
          obj = form.save()
          form = ProductForm({'slug': 'teddy-bear-blue'})
          self.assertEqual(len(form.errors), 1)
          self.assertEqual(form.errors['slug'], ['Product with this Slug already exists.'])
          form = ProductForm({'slug': 'teddy-bear-blue'}, instance=obj)
          self.assertTrue(form.is_valid())
  
      def test_unique_together(self):
          """ModelForm test of unique_together constraint"""
          form = PriceForm({'price': '6.00', 'quantity': '1'})
          self.assertTrue(form.is_valid())
          form.save()
          form = PriceForm({'price': '6.00', 'quantity': '1'})
          self.assertFalse(form.is_valid())
          self.assertEqual(len(form.errors), 1)
          self.assertEqual(form.errors['__all__'], ['Price with this Price and Quantity already exists.'])
  
      def test_multiple_field_unique_together(self):
          """
          When the same field is involved in multiple unique_together
          constraints, we need to make sure we don't remove the data for it
          before doing all the validation checking (not just failing after
          the first one).
          """
          class TripleForm(forms.ModelForm):
              class Meta:
                  model = Triple
                  fields = '__all__'
  
          Triple.objects.create(left=1, middle=2, right=3)
  
          form = TripleForm({'left': '1', 'middle': '2', 'right': '3'})
          self.assertFalse(form.is_valid())
  
          form = TripleForm({'left': '1', 'middle': '3', 'right': '1'})
          self.assertTrue(form.is_valid())
  
      @skipUnlessDBFeature('supports_nullable_unique_constraints')
      def test_unique_null(self):
          title = 'I May Be Wrong But I Doubt It'
          form = BookForm({'title': title, 'author': self.writer.pk})
          self.assertTrue(form.is_valid())
          form.save()
          form = BookForm({'title': title, 'author': self.writer.pk})
          self.assertFalse(form.is_valid())
          self.assertEqual(len(form.errors), 1)
          self.assertEqual(form.errors['__all__'], ['Book with this Title and Author already exists.'])
          form = BookForm({'title': title})
          self.assertTrue(form.is_valid())
          form.save()
          form = BookForm({'title': title})
          self.assertTrue(form.is_valid())
  
      def test_inherited_unique(self):
          title = 'Boss'
          Book.objects.create(title=title, author=self.writer, special_id=1)
          form = DerivedBookForm({'title': 'Other', 'author': self.writer.pk, 'special_id': '1', 'isbn': '12345'})
          self.assertFalse(form.is_valid())
          self.assertEqual(len(form.errors), 1)
          self.assertEqual(form.errors['special_id'], ['Book with this Special id already exists.'])
  
      def test_inherited_unique_together(self):
          title = 'Boss'
          form = BookForm({'title': title, 'author': self.writer.pk})
          self.assertTrue(form.is_valid())
          form.save()
          form = DerivedBookForm({'title': title, 'author': self.writer.pk, 'isbn': '12345'})
          self.assertFalse(form.is_valid())
          self.assertEqual(len(form.errors), 1)
          self.assertEqual(form.errors['__all__'], ['Book with this Title and Author already exists.'])
  
      def test_abstract_inherited_unique(self):
          title = 'Boss'
          isbn = '12345'
          DerivedBook.objects.create(title=title, author=self.writer, isbn=isbn)
          form = DerivedBookForm({'title': 'Other', 'author': self.writer.pk, 'isbn': isbn})
          self.assertFalse(form.is_valid())
          self.assertEqual(len(form.errors), 1)
          self.assertEqual(form.errors['isbn'], ['Derived book with this Isbn already exists.'])
  
      def test_abstract_inherited_unique_together(self):
          title = 'Boss'
          isbn = '12345'
          DerivedBook.objects.create(title=title, author=self.writer, isbn=isbn)
          form = DerivedBookForm({
              'title': 'Other',
              'author': self.writer.pk,
              'isbn': '9876',
              'suffix1': '0',
              'suffix2': '0'
          })
          self.assertFalse(form.is_valid())
          self.assertEqual(len(form.errors), 1)
          self.assertEqual(form.errors['__all__'],
                           ['Derived book with this Suffix1 and Suffix2 already exists.'])
  
      def test_explicitpk_unspecified(self):
          """Test for primary_key being in the form and failing validation."""
          form = ExplicitPKForm({'key': '', 'desc': ''})
          self.assertFalse(form.is_valid())
  
      def test_explicitpk_unique(self):
          """Ensure keys and blank character strings are tested for uniqueness."""
          form = ExplicitPKForm({'key': 'key1', 'desc': ''})
          self.assertTrue(form.is_valid())
          form.save()
          form = ExplicitPKForm({'key': 'key1', 'desc': ''})
          self.assertFalse(form.is_valid())
          if connection.features.interprets_empty_strings_as_nulls:
              self.assertEqual(len(form.errors), 1)
              self.assertEqual(form.errors['key'], ['Explicit pk with this Key already exists.'])
          else:
              self.assertEqual(len(form.errors), 3)
              self.assertEqual(form.errors['__all__'], ['Explicit pk with this Key and Desc already exists.'])
              self.assertEqual(form.errors['desc'], ['Explicit pk with this Desc already exists.'])
              self.assertEqual(form.errors['key'], ['Explicit pk with this Key already exists.'])
  
      def test_unique_for_date(self):
          p = Post.objects.create(
              title="Django 1.0 is released", slug="Django 1.0",
              subtitle="Finally", posted=datetime.date(2008, 9, 3),
          )
          form = PostForm({'title': "Django 1.0 is released", 'posted': '2008-09-03'})
          self.assertFalse(form.is_valid())
          self.assertEqual(len(form.errors), 1)
          self.assertEqual(form.errors['title'], ['Title must be unique for Posted date.'])
          form = PostForm({'title': "Work on Django 1.1 begins", 'posted': '2008-09-03'})
          self.assertTrue(form.is_valid())
          form = PostForm({'title': "Django 1.0 is released", 'posted': '2008-09-04'})
          self.assertTrue(form.is_valid())
          form = PostForm({'slug': "Django 1.0", 'posted': '2008-01-01'})
          self.assertFalse(form.is_valid())
          self.assertEqual(len(form.errors), 1)
          self.assertEqual(form.errors['slug'], ['Slug must be unique for Posted year.'])
          form = PostForm({'subtitle': "Finally", 'posted': '2008-09-30'})
          self.assertFalse(form.is_valid())
          self.assertEqual(form.errors['subtitle'], ['Subtitle must be unique for Posted month.'])
          data = {'subtitle': "Finally", "title": "Django 1.0 is released", "slug": "Django 1.0", 'posted': '2008-09-03'}
          form = PostForm(data, instance=p)
          self.assertTrue(form.is_valid())
          form = PostForm({'title': "Django 1.0 is released"})
          self.assertFalse(form.is_valid())
          self.assertEqual(len(form.errors), 1)
          self.assertEqual(form.errors['posted'], ['This field is required.'])
  
      def test_unique_for_date_in_exclude(self):
          """
          If the date for unique_for_* constraints is excluded from the
          ModelForm (in this case 'posted' has editable=False, then the
          constraint should be ignored.
          """
          class DateTimePostForm(forms.ModelForm):
              class Meta:
                  model = DateTimePost
                  fields = '__all__'
  
          DateTimePost.objects.create(
              title="Django 1.0 is released", slug="Django 1.0",
              subtitle="Finally", posted=datetime.datetime(2008, 9, 3, 10, 10, 1),
          )
          # 'title' has unique_for_date='posted'
          form = DateTimePostForm({'title': "Django 1.0 is released", 'posted': '2008-09-03'})
          self.assertTrue(form.is_valid())
          # 'slug' has unique_for_year='posted'
          form = DateTimePostForm({'slug': "Django 1.0", 'posted': '2008-01-01'})
          self.assertTrue(form.is_valid())
          # 'subtitle' has unique_for_month='posted'
          form = DateTimePostForm({'subtitle': "Finally", 'posted': '2008-09-30'})
          self.assertTrue(form.is_valid())
  
      def test_inherited_unique_for_date(self):
          p = Post.objects.create(
              title="Django 1.0 is released", slug="Django 1.0",
              subtitle="Finally", posted=datetime.date(2008, 9, 3),
          )
          form = DerivedPostForm({'title': "Django 1.0 is released", 'posted': '2008-09-03'})
          self.assertFalse(form.is_valid())
          self.assertEqual(len(form.errors), 1)
          self.assertEqual(form.errors['title'], ['Title must be unique for Posted date.'])
          form = DerivedPostForm({'title': "Work on Django 1.1 begins", 'posted': '2008-09-03'})
          self.assertTrue(form.is_valid())
          form = DerivedPostForm({'title': "Django 1.0 is released", 'posted': '2008-09-04'})
          self.assertTrue(form.is_valid())
          form = DerivedPostForm({'slug': "Django 1.0", 'posted': '2008-01-01'})
          self.assertFalse(form.is_valid())
          self.assertEqual(len(form.errors), 1)
          self.assertEqual(form.errors['slug'], ['Slug must be unique for Posted year.'])
          form = DerivedPostForm({'subtitle': "Finally", 'posted': '2008-09-30'})
          self.assertFalse(form.is_valid())
          self.assertEqual(form.errors['subtitle'], ['Subtitle must be unique for Posted month.'])
          data = {'subtitle': "Finally", "title": "Django 1.0 is released", "slug": "Django 1.0", 'posted': '2008-09-03'}
          form = DerivedPostForm(data, instance=p)
          self.assertTrue(form.is_valid())
  
      def test_unique_for_date_with_nullable_date(self):
          class FlexDatePostForm(forms.ModelForm):
              class Meta:
                  model = FlexibleDatePost
                  fields = '__all__'
  
          p = FlexibleDatePost.objects.create(
              title="Django 1.0 is released", slug="Django 1.0",
              subtitle="Finally", posted=datetime.date(2008, 9, 3),
          )
  
          form = FlexDatePostForm({'title': "Django 1.0 is released"})
          self.assertTrue(form.is_valid())
          form = FlexDatePostForm({'slug': "Django 1.0"})
          self.assertTrue(form.is_valid())
          form = FlexDatePostForm({'subtitle': "Finally"})
          self.assertTrue(form.is_valid())
          data = {'subtitle': "Finally", "title": "Django 1.0 is released", "slug": "Django 1.0"}
          form = FlexDatePostForm(data, instance=p)
          self.assertTrue(form.is_valid())
  
      def test_override_unique_message(self):
          class CustomProductForm(ProductForm):
              class Meta(ProductForm.Meta):
                  error_messages = {
                      'slug': {
                          'unique': "%(model_name)s's %(field_label)s not unique.",
                      }
                  }
  
          Product.objects.create(slug='teddy-bear-blue')
          form = CustomProductForm({'slug': 'teddy-bear-blue'})
          self.assertEqual(len(form.errors), 1)
          self.assertEqual(form.errors['slug'], ["Product's Slug not unique."])
  
      def test_override_unique_together_message(self):
          class CustomPriceForm(PriceForm):
              class Meta(PriceForm.Meta):
                  error_messages = {
                      NON_FIELD_ERRORS: {
                          'unique_together': "%(model_name)s's %(field_labels)s not unique.",
                      }
                  }
  
          Price.objects.create(price=6.00, quantity=1)
          form = CustomPriceForm({'price': '6.00', 'quantity': '1'})
          self.assertEqual(len(form.errors), 1)
          self.assertEqual(form.errors[NON_FIELD_ERRORS], ["Price's Price and Quantity not unique."])
  
      def test_override_unique_for_date_message(self):
          class CustomPostForm(PostForm):
              class Meta(PostForm.Meta):
                  error_messages = {
                      'title': {
                          'unique_for_date': (
                              "%(model_name)s's %(field_label)s not unique "
                              "for %(date_field_label)s date."
                          ),
                      }
                  }
  
          Post.objects.create(
              title="Django 1.0 is released", slug="Django 1.0",
              subtitle="Finally", posted=datetime.date(2008, 9, 3),
          )
          form = CustomPostForm({'title': "Django 1.0 is released", 'posted': '2008-09-03'})
          self.assertEqual(len(form.errors), 1)
          self.assertEqual(form.errors['title'], ["Post's Title not unique for Posted date."])
  
  
  class ModelToDictTests(TestCase):
      """
      Tests for forms.models.model_to_dict
      """
      def test_model_to_dict_many_to_many(self):
          categories = [
              Category(name='TestName1', slug='TestName1', url='url1'),
              Category(name='TestName2', slug='TestName2', url='url2'),
              Category(name='TestName3', slug='TestName3', url='url3')
          ]
          for c in categories:
              c.save()
          writer = Writer(name='Test writer')
          writer.save()
  
          art = Article(
              headline='Test article',
              slug='test-article',
              pub_date=datetime.date(1988, 1, 4),
              writer=writer,
              article='Hello.'
          )
          art.save()
          for c in categories:
              art.categories.add(c)
          art.save()
  
          with self.assertNumQueries(1):
              d = model_to_dict(art)
  
          # Ensure all many-to-many categories appear in model_to_dict
          for c in categories:
              self.assertIn(c.pk, d['categories'])
          # Ensure many-to-many relation appears as a list
          self.assertIsInstance(d['categories'], list)
  
      def test_reuse_prefetched(self):
          # model_to_dict should not hit the database if it can reuse
          # the data populated by prefetch_related.
          categories = [
              Category(name='TestName1', slug='TestName1', url='url1'),
              Category(name='TestName2', slug='TestName2', url='url2'),
              Category(name='TestName3', slug='TestName3', url='url3')
          ]
          for c in categories:
              c.save()
          writer = Writer(name='Test writer')
          writer.save()
  
          art = Article(
              headline='Test article',
              slug='test-article',
              pub_date=datetime.date(1988, 1, 4),
              writer=writer,
              article='Hello.'
          )
          art.save()
          for c in categories:
              art.categories.add(c)
  
          art = Article.objects.prefetch_related('categories').get(pk=art.pk)
  
          with self.assertNumQueries(0):
              d = model_to_dict(art)
  
          # Ensure all many-to-many categories appear in model_to_dict
          for c in categories:
              self.assertIn(c.pk, d['categories'])
          # Ensure many-to-many relation appears as a list
          self.assertIsInstance(d['categories'], list)
  
  
  class ModelFormBasicTests(TestCase):
      def create_basic_data(self):
          self.c1 = Category.objects.create(
              name="Entertainment", slug="entertainment", url="entertainment")
          self.c2 = Category.objects.create(
              name="It's a test", slug="its-test", url="test")
          self.c3 = Category.objects.create(
              name="Third test", slug="third-test", url="third")
          self.w_royko = Writer.objects.create(name='Mike Royko')
          self.w_woodward = Writer.objects.create(name='Bob Woodward')
  
      def test_base_form(self):
          self.assertEqual(Category.objects.count(), 0)
          f = BaseCategoryForm()
          self.assertHTMLEqual(
              str(f),
              """<tr><th><label for="id_name">Name:</label></th>
  <td><input id="id_name" type="text" name="name" maxlength="20" required /></td></tr>
  <tr><th><label for="id_slug">Slug:</label></th>
  <td><input id="id_slug" type="text" name="slug" maxlength="20" required /></td></tr>
  <tr><th><label for="id_url">The URL:</label></th>
  <td><input id="id_url" type="text" name="url" maxlength="40" required /></td></tr>"""
          )
          self.assertHTMLEqual(
              str(f.as_ul()),
              """<li><label for="id_name">Name:</label> <input id="id_name" type="text" name="name" maxlength="20" required /></li>
  <li><label for="id_slug">Slug:</label> <input id="id_slug" type="text" name="slug" maxlength="20" required /></li>
  <li><label for="id_url">The URL:</label> <input id="id_url" type="text" name="url" maxlength="40" required /></li>"""
          )
          self.assertHTMLEqual(
              str(f["name"]),
              """<input id="id_name" type="text" name="name" maxlength="20" required />""")
  
      def test_auto_id(self):
          f = BaseCategoryForm(auto_id=False)
          self.assertHTMLEqual(
              str(f.as_ul()),
              """<li>Name: <input type="text" name="name" maxlength="20" required /></li>
  <li>Slug: <input type="text" name="slug" maxlength="20" required /></li>
  <li>The URL: <input type="text" name="url" maxlength="40" required /></li>"""
          )
  
      def test_initial_values(self):
          self.create_basic_data()
          # Initial values can be provided for model forms
          f = ArticleForm(
              auto_id=False,
              initial={
                  'headline': 'Your headline here',
                  'categories': [str(self.c1.id), str(self.c2.id)]
              })
          self.assertHTMLEqual(
              f.as_ul(),
              '''<li>Headline: <input type="text" name="headline" value="Your headline here" maxlength="50" required /></li>
  <li>Slug: <input type="text" name="slug" maxlength="50" required /></li>
  <li>Pub date: <input type="text" name="pub_date" required /></li>
  <li>Writer: <select name="writer" required>
  <option value="" selected="selected">---------</option>
  <option value="%s">Bob Woodward</option>
  <option value="%s">Mike Royko</option>
  </select></li>
  <li>Article: <textarea rows="10" cols="40" name="article" required></textarea></li>
  <li>Categories: <select multiple="multiple" name="categories">
  <option value="%s" selected="selected">Entertainment</option>
  <option value="%s" selected="selected">It&#39;s a test</option>
  <option value="%s">Third test</option>
  </select></li>
  <li>Status: <select name="status">
  <option value="" selected="selected">---------</option>
  <option value="1">Draft</option>
  <option value="2">Pending</option>
  <option value="3">Live</option>
  </select></li>''' % (self.w_woodward.pk, self.w_royko.pk, self.c1.pk, self.c2.pk, self.c3.pk))
  
          # When the ModelForm is passed an instance, that instance's current values are
          # inserted as 'initial' data in each Field.
          f = RoykoForm(auto_id=False, instance=self.w_royko)
          self.assertHTMLEqual(
              six.text_type(f),
              '''<tr><th>Name:</th><td><input type="text" name="name" value="Mike Royko" maxlength="50" required /><br />
              <span class="helptext">Use both first and last names.</span></td></tr>'''
          )
  
          art = Article.objects.create(
              headline='Test article',
              slug='test-article',
              pub_date=datetime.date(1988, 1, 4),
              writer=self.w_royko,
              article='Hello.'
          )
          art_id_1 = art.id
  
          f = ArticleForm(auto_id=False, instance=art)
          self.assertHTMLEqual(
              f.as_ul(),
              '''<li>Headline: <input type="text" name="headline" value="Test article" maxlength="50" required /></li>
  <li>Slug: <input type="text" name="slug" value="test-article" maxlength="50" required /></li>
  <li>Pub date: <input type="text" name="pub_date" value="1988-01-04" required /></li>
  <li>Writer: <select name="writer" required>
  <option value="">---------</option>
  <option value="%s">Bob Woodward</option>
  <option value="%s" selected="selected">Mike Royko</option>
  </select></li>
  <li>Article: <textarea rows="10" cols="40" name="article" required>Hello.</textarea></li>
  <li>Categories: <select multiple="multiple" name="categories">
  <option value="%s">Entertainment</option>
  <option value="%s">It&#39;s a test</option>
  <option value="%s">Third test</option>
  </select></li>
  <li>Status: <select name="status">
  <option value="" selected="selected">---------</option>
  <option value="1">Draft</option>
  <option value="2">Pending</option>
  <option value="3">Live</option>
  </select></li>''' % (self.w_woodward.pk, self.w_royko.pk, self.c1.pk, self.c2.pk, self.c3.pk))
  
          f = ArticleForm({
              'headline': 'Test headline',
              'slug': 'test-headline',
              'pub_date': '1984-02-06',
              'writer': six.text_type(self.w_royko.pk),
              'article': 'Hello.'
          }, instance=art)
          self.assertEqual(f.errors, {})
          self.assertTrue(f.is_valid())
          test_art = f.save()
          self.assertEqual(test_art.id, art_id_1)
          test_art = Article.objects.get(id=art_id_1)
          self.assertEqual(test_art.headline, 'Test headline')
  
      def test_m2m_initial_callable(self):
          """
          Regression for #10349: A callable can be provided as the initial value for an m2m field
          """
          self.maxDiff = 1200
          self.create_basic_data()
  
          # Set up a callable initial value
          def formfield_for_dbfield(db_field, **kwargs):
              if db_field.name == 'categories':
                  kwargs['initial'] = lambda: Category.objects.all().order_by('name')[:2]
              return db_field.formfield(**kwargs)
  
          # Create a ModelForm, instantiate it, and check that the output is as expected
          ModelForm = modelform_factory(Article, fields=['headline', 'categories'],
                                        formfield_callback=formfield_for_dbfield)
          form = ModelForm()
          self.assertHTMLEqual(
              form.as_ul(),
              """<li><label for="id_headline">Headline:</label>
  <input id="id_headline" type="text" name="headline" maxlength="50" required /></li>
  <li><label for="id_categories">Categories:</label>
  <select multiple="multiple" name="categories" id="id_categories">
  <option value="%d" selected="selected">Entertainment</option>
  <option value="%d" selected="selected">It&39;s a test</option>
  <option value="%d">Third test</option>
  </select></li>"""
              % (self.c1.pk, self.c2.pk, self.c3.pk))
  
      def test_basic_creation(self):
          self.assertEqual(Category.objects.count(), 0)
          f = BaseCategoryForm({'name': 'Entertainment',
                                'slug': 'entertainment',
                                'url': 'entertainment'})
          self.assertTrue(f.is_valid())
          self.assertEqual(f.cleaned_data['name'], 'Entertainment')
          self.assertEqual(f.cleaned_data['slug'], 'entertainment')
          self.assertEqual(f.cleaned_data['url'], 'entertainment')
          c1 = f.save()
          # Testing whether the same object is returned from the
          # ORM... not the fastest way...
  
          self.assertEqual(Category.objects.count(), 1)
          self.assertEqual(c1, Category.objects.all()[0])
          self.assertEqual(c1.name, "Entertainment")
  
      def test_save_commit_false(self):
          # If you call save() with commit=False, then it will return an object that
          # hasn't yet been saved to the database. In this case, it's up to you to call
          # save() on the resulting model instance.
          f = BaseCategoryForm({'name': 'Third test', 'slug': 'third-test', 'url': 'third'})
          self.assertTrue(f.is_valid())
          c1 = f.save(commit=False)
          self.assertEqual(c1.name, "Third test")
          self.assertEqual(Category.objects.count(), 0)
          c1.save()
          self.assertEqual(Category.objects.count(), 1)
  
      def test_save_with_data_errors(self):
          # If you call save() with invalid data, you'll get a ValueError.
          f = BaseCategoryForm({'name': '', 'slug': 'not a slug!', 'url': 'foo'})
          self.assertEqual(f.errors['name'], ['This field is required.'])
          self.assertEqual(
              f.errors['slug'],
              ["Enter a valid 'slug' consisting of letters, numbers, underscores or hyphens."]
          )
          self.assertEqual(f.cleaned_data, {'url': 'foo'})
          with self.assertRaises(ValueError):
              f.save()
          f = BaseCategoryForm({'name': '', 'slug': '', 'url': 'foo'})
          with self.assertRaises(ValueError):
              f.save()
  
      def test_multi_fields(self):
          self.create_basic_data()
          self.maxDiff = None
          # ManyToManyFields are represented by a MultipleChoiceField, ForeignKeys and any
          # fields with the 'choices' attribute are represented by a ChoiceField.
          f = ArticleForm(auto_id=False)
          self.assertHTMLEqual(
              six.text_type(f),
              '''<tr><th>Headline:</th><td><input type="text" name="headline" maxlength="50" required /></td></tr>
  <tr><th>Slug:</th><td><input type="text" name="slug" maxlength="50" required /></td></tr>
  <tr><th>Pub date:</th><td><input type="text" name="pub_date" required /></td></tr>
  <tr><th>Writer:</th><td><select name="writer" required>
  <option value="" selected="selected">---------</option>
  <option value="%s">Bob Woodward</option>
  <option value="%s">Mike Royko</option>
  </select></td></tr>
  <tr><th>Article:</th><td><textarea rows="10" cols="40" name="article" required></textarea></td></tr>
  <tr><th>Categories:</th><td><select multiple="multiple" name="categories">
  <option value="%s">Entertainment</option>
  <option value="%s">It&#39;s a test</option>
  <option value="%s">Third test</option>
  </select></td></tr>
  <tr><th>Status:</th><td><select name="status">
  <option value="" selected="selected">---------</option>
  <option value="1">Draft</option>
  <option value="2">Pending</option>
  <option value="3">Live</option>
  </select></td></tr>''' % (self.w_woodward.pk, self.w_royko.pk, self.c1.pk, self.c2.pk, self.c3.pk))
  
          # Add some categories and test the many-to-many form output.
          new_art = Article.objects.create(
              article="Hello.", headline="New headline", slug="new-headline",
              pub_date=datetime.date(1988, 1, 4), writer=self.w_royko)
          new_art.categories.add(Category.objects.get(name='Entertainment'))
          self.assertQuerysetEqual(new_art.categories.all(), ["Entertainment"])
          f = ArticleForm(auto_id=False, instance=new_art)
          self.assertHTMLEqual(
              f.as_ul(),
              '''<li>Headline: <input type="text" name="headline" value="New headline" maxlength="50" required /></li>
  <li>Slug: <input type="text" name="slug" value="new-headline" maxlength="50" required /></li>
  <li>Pub date: <input type="text" name="pub_date" value="1988-01-04" required /></li>
  <li>Writer: <select name="writer" required>
  <option value="">---------</option>
  <option value="%s">Bob Woodward</option>
  <option value="%s" selected="selected">Mike Royko</option>
  </select></li>
  <li>Article: <textarea rows="10" cols="40" name="article" required>Hello.</textarea></li>
  <li>Categories: <select multiple="multiple" name="categories">
  <option value="%s" selected="selected">Entertainment</option>
  <option value="%s">It&#39;s a test</option>
  <option value="%s">Third test</option>
  </select></li>
  <li>Status: <select name="status">
  <option value="" selected="selected">---------</option>
  <option value="1">Draft</option>
  <option value="2">Pending</option>
  <option value="3">Live</option>
  </select></li>''' % (self.w_woodward.pk, self.w_royko.pk, self.c1.pk, self.c2.pk, self.c3.pk))
  
      def test_subset_fields(self):
          # You can restrict a form to a subset of the complete list of fields
          # by providing a 'fields' argument. If you try to save a
          # model created with such a form, you need to ensure that the fields
          # that are _not_ on the form have default values, or are allowed to have
          # a value of None. If a field isn't specified on a form, the object created
          # from the form can't provide a value for that field!
          class PartialArticleForm(forms.ModelForm):
              class Meta:
                  model = Article
                  fields = ('headline', 'pub_date')
  
          f = PartialArticleForm(auto_id=False)
          self.assertHTMLEqual(
              six.text_type(f),
              '''<tr><th>Headline:</th><td><input type="text" name="headline" maxlength="50" required /></td></tr>
  <tr><th>Pub date:</th><td><input type="text" name="pub_date" required /></td></tr>''')
  
          # You can create a form over a subset of the available fields
          # by specifying a 'fields' argument to form_for_instance.
          class PartialArticleFormWithSlug(forms.ModelForm):
              class Meta:
                  model = Article
                  fields = ('headline', 'slug', 'pub_date')
  
          w_royko = Writer.objects.create(name='Mike Royko')
          art = Article.objects.create(
              article="Hello.", headline="New headline", slug="new-headline",
              pub_date=datetime.date(1988, 1, 4), writer=w_royko)
          f = PartialArticleFormWithSlug({
              'headline': 'New headline',
              'slug': 'new-headline',
              'pub_date': '1988-01-04'
          }, auto_id=False, instance=art)
          self.assertHTMLEqual(
              f.as_ul(),
              '''<li>Headline: <input type="text" name="headline" value="New headline" maxlength="50" required /></li>
  <li>Slug: <input type="text" name="slug" value="new-headline" maxlength="50" required /></li>
  <li>Pub date: <input type="text" name="pub_date" value="1988-01-04" required /></li>'''
          )
          self.assertTrue(f.is_valid())
          new_art = f.save()
          self.assertEqual(new_art.id, art.id)
          new_art = Article.objects.get(id=art.id)
          self.assertEqual(new_art.headline, 'New headline')
  
      def test_m2m_editing(self):
          self.create_basic_data()
          form_data = {
              'headline': 'New headline',
              'slug': 'new-headline',
              'pub_date': '1988-01-04',
              'writer': six.text_type(self.w_royko.pk),
              'article': 'Hello.',
              'categories': [six.text_type(self.c1.id), six.text_type(self.c2.id)]
          }
          # Create a new article, with categories, via the form.
          f = ArticleForm(form_data)
          new_art = f.save()
          new_art = Article.objects.get(id=new_art.id)
          art_id_1 = new_art.id
          self.assertQuerysetEqual(new_art.categories.order_by('name'), ["Entertainment", "It's a test"])
  
          # Now, submit form data with no categories. This deletes the existing categories.
          form_data['categories'] = []
          f = ArticleForm(form_data, instance=new_art)
          new_art = f.save()
          self.assertEqual(new_art.id, art_id_1)
          new_art = Article.objects.get(id=art_id_1)
          self.assertQuerysetEqual(new_art.categories.all(), [])
  
          # Create a new article, with no categories, via the form.
          f = ArticleForm(form_data)
          new_art = f.save()
          art_id_2 = new_art.id
          self.assertNotIn(art_id_2, (None, art_id_1))
          new_art = Article.objects.get(id=art_id_2)
          self.assertQuerysetEqual(new_art.categories.all(), [])
  
          # Create a new article, with categories, via the form, but use commit=False.
          # The m2m data won't be saved until save_m2m() is invoked on the form.
          form_data['categories'] = [six.text_type(self.c1.id), six.text_type(self.c2.id)]
          f = ArticleForm(form_data)
          new_art = f.save(commit=False)
  
          # Manually save the instance
          new_art.save()
          art_id_3 = new_art.id
          self.assertNotIn(art_id_3, (None, art_id_1, art_id_2))
  
          # The instance doesn't have m2m data yet
          new_art = Article.objects.get(id=art_id_3)
          self.assertQuerysetEqual(new_art.categories.all(), [])
  
          # Save the m2m data on the form
          f.save_m2m()
          self.assertQuerysetEqual(new_art.categories.order_by('name'), ["Entertainment", "It's a test"])
  
      def test_custom_form_fields(self):
          # Here, we define a custom ModelForm. Because it happens to have the same fields as
          # the Category model, we can just call the form's save() to apply its changes to an
          # existing Category instance.
          class ShortCategory(forms.ModelForm):
              name = forms.CharField(max_length=5)
              slug = forms.CharField(max_length=5)
              url = forms.CharField(max_length=3)
  
              class Meta:
                  model = Category
                  fields = '__all__'
  
          cat = Category.objects.create(name='Third test')
          form = ShortCategory({'name': 'Third', 'slug': 'third', 'url': '3rd'}, instance=cat)
          self.assertEqual(form.save().name, 'Third')
          self.assertEqual(Category.objects.get(id=cat.id).name, 'Third')
  
      def test_runtime_choicefield_populated(self):
          self.maxDiff = None
          # Here, we demonstrate that choices for a ForeignKey ChoiceField are determined
          # at runtime, based on the data in the database when the form is displayed, not
          # the data in the database when the form is instantiated.
          self.create_basic_data()
          f = ArticleForm(auto_id=False)
          self.assertHTMLEqual(
              f.as_ul(),
              '''<li>Headline: <input type="text" name="headline" maxlength="50" required /></li>
  <li>Slug: <input type="text" name="slug" maxlength="50" required /></li>
  <li>Pub date: <input type="text" name="pub_date" required /></li>
  <li>Writer: <select name="writer" required>
  <option value="" selected="selected">---------</option>
  <option value="%s">Bob Woodward</option>
  <option value="%s">Mike Royko</option>
  </select></li>
  <li>Article: <textarea rows="10" cols="40" name="article" required></textarea></li>
  <li>Categories: <select multiple="multiple" name="categories">
  <option value="%s">Entertainment</option>
  <option value="%s">It&#39;s a test</option>
  <option value="%s">Third test</option>
  </select> </li>
  <li>Status: <select name="status">
  <option value="" selected="selected">---------</option>
  <option value="1">Draft</option>
  <option value="2">Pending</option>
  <option value="3">Live</option>
  </select></li>''' % (self.w_woodward.pk, self.w_royko.pk, self.c1.pk, self.c2.pk, self.c3.pk))
  
          c4 = Category.objects.create(name='Fourth', url='4th')
          w_bernstein = Writer.objects.create(name='Carl Bernstein')
          self.assertHTMLEqual(
              f.as_ul(),
              '''<li>Headline: <input type="text" name="headline" maxlength="50" required /></li>
  <li>Slug: <input type="text" name="slug" maxlength="50" required /></li>
  <li>Pub date: <input type="text" name="pub_date" required /></li>
  <li>Writer: <select name="writer" required>
  <option value="" selected="selected">---------</option>
  <option value="%s">Bob Woodward</option>
  <option value="%s">Carl Bernstein</option>
  <option value="%s">Mike Royko</option>
  </select></li>
  <li>Article: <textarea rows="10" cols="40" name="article" required></textarea></li>
  <li>Categories: <select multiple="multiple" name="categories">
  <option value="%s">Entertainment</option>
  <option value="%s">It&#39;s a test</option>
  <option value="%s">Third test</option>
  <option value="%s">Fourth</option>
  </select></li>
  <li>Status: <select name="status">
  <option value="" selected="selected">---------</option>
  <option value="1">Draft</option>
  <option value="2">Pending</option>
  <option value="3">Live</option>
  </select></li>''' % (self.w_woodward.pk, w_bernstein.pk, self.w_royko.pk, self.c1.pk, self.c2.pk, self.c3.pk, c4.pk))
  
  
  class ModelChoiceFieldTests(TestCase):
      def setUp(self):
          self.c1 = Category.objects.create(
              name="Entertainment", slug="entertainment", url="entertainment")
          self.c2 = Category.objects.create(
              name="It's a test", slug="its-test", url="test")
          self.c3 = Category.objects.create(
              name="Third", slug="third-test", url="third")
  
      # ModelChoiceField ############################################################
      def test_modelchoicefield(self):
          f = forms.ModelChoiceField(Category.objects.all())
          self.assertEqual(list(f.choices), [
              ('', '---------'),
              (self.c1.pk, 'Entertainment'),
              (self.c2.pk, "It's a test"),
              (self.c3.pk, 'Third')])
          with self.assertRaises(ValidationError):
              f.clean('')
          with self.assertRaises(ValidationError):
              f.clean(None)
          with self.assertRaises(ValidationError):
              f.clean(0)
  
          # Invalid types that require TypeError to be caught (#22808).
          with self.assertRaises(ValidationError):
              f.clean([['fail']])
          with self.assertRaises(ValidationError):
              f.clean([{'foo': 'bar'}])
  
          self.assertEqual(f.clean(self.c2.id).name, "It's a test")
          self.assertEqual(f.clean(self.c3.id).name, 'Third')
  
          # Add a Category object *after* the ModelChoiceField has already been
          # instantiated. This proves clean() checks the database during clean() rather
          # than caching it at time of instantiation.
          c4 = Category.objects.create(name='Fourth', url='4th')
          self.assertEqual(f.clean(c4.id).name, 'Fourth')
  
          # Delete a Category object *after* the ModelChoiceField has already been
          # instantiated. This proves clean() checks the database during clean() rather
          # than caching it at time of instantiation.
          Category.objects.get(url='4th').delete()
          with self.assertRaises(ValidationError):
              f.clean(c4.id)
  
      def test_modelchoicefield_choices(self):
          f = forms.ModelChoiceField(Category.objects.filter(pk=self.c1.id), required=False)
          self.assertIsNone(f.clean(''))
          self.assertEqual(f.clean(str(self.c1.id)).name, "Entertainment")
          with self.assertRaises(ValidationError):
              f.clean('100')
  
          # len can be called on choices
          self.assertEqual(len(f.choices), 2)
  
          # queryset can be changed after the field is created.
          f.queryset = Category.objects.exclude(name='Third')
          self.assertEqual(list(f.choices), [
              ('', '---------'),
              (self.c1.pk, 'Entertainment'),
              (self.c2.pk, "It's a test")])
          self.assertEqual(f.clean(self.c2.id).name, "It's a test")
          with self.assertRaises(ValidationError):
              f.clean(self.c3.id)
  
          # check that we can safely iterate choices repeatedly
          gen_one = list(f.choices)
          gen_two = f.choices
          self.assertEqual(gen_one[2], (self.c2.pk, "It's a test"))
          self.assertEqual(list(gen_two), [
              ('', '---------'),
              (self.c1.pk, 'Entertainment'),
              (self.c2.pk, "It's a test")])
  
          # check that we can override the label_from_instance method to print custom labels (#4620)
          f.queryset = Category.objects.all()
          f.label_from_instance = lambda obj: "category " + str(obj)
          self.assertEqual(list(f.choices), [
              ('', '---------'),
              (self.c1.pk, 'category Entertainment'),
              (self.c2.pk, "category It's a test"),
              (self.c3.pk, 'category Third')])
  
      def test_modelchoicefield_11183(self):
          """
          Regression test for ticket #11183.
          """
          class ModelChoiceForm(forms.Form):
              category = forms.ModelChoiceField(Category.objects.all())
  
          form1 = ModelChoiceForm()
          field1 = form1.fields['category']
          # To allow the widget to change the queryset of field1.widget.choices correctly,
          # without affecting other forms, the following must hold:
          self.assertIsNot(field1, ModelChoiceForm.base_fields['category'])
          self.assertIs(field1.widget.choices.field, field1)
  
      def test_modelchoicefield_22745(self):
          """
          #22745 -- Make sure that ModelChoiceField with RadioSelect widget
          doesn't produce unnecessary db queries when accessing its BoundField's
          attrs.
          """
          class ModelChoiceForm(forms.Form):
              category = forms.ModelChoiceField(Category.objects.all(), widget=forms.RadioSelect)
  
          form = ModelChoiceForm()
          field = form['category']  # BoundField
          template = Template('{{ field.name }}{{ field }}{{ field.help_text }}')
          with self.assertNumQueries(1):
              template.render(Context({'field': field}))
  
      def test_modelchoicefield_index_renderer(self):
          field = forms.ModelChoiceField(Category.objects.all(), widget=forms.RadioSelect)
          self.assertEqual(
              str(field.widget.get_renderer('foo', [])[0]),
              '<label><input name="foo" type="radio" value="" /> ---------</label>'
          )
  
      def test_modelchoicefield_iterator(self):
          """
          Iterator defaults to ModelChoiceIterator and can be overridden with
          the iterator attribute on a ModelChoiceField subclass.
          """
          field = forms.ModelChoiceField(Category.objects.all())
          self.assertIsInstance(field.choices, ModelChoiceIterator)
  
          class CustomModelChoiceIterator(ModelChoiceIterator):
              pass
  
          class CustomModelChoiceField(forms.ModelChoiceField):
              iterator = CustomModelChoiceIterator
  
          field = CustomModelChoiceField(Category.objects.all())
          self.assertIsInstance(field.choices, CustomModelChoiceIterator)
  
  
  class ModelMultipleChoiceFieldTests(TestCase):
      def setUp(self):
          self.c1 = Category.objects.create(
              name="Entertainment", slug="entertainment", url="entertainment")
          self.c2 = Category.objects.create(
              name="It's a test", slug="its-test", url="test")
          self.c3 = Category.objects.create(
              name="Third", slug="third-test", url="third")
  
      def test_model_multiple_choice_field(self):
          f = forms.ModelMultipleChoiceField(Category.objects.all())
          self.assertEqual(list(f.choices), [
              (self.c1.pk, 'Entertainment'),
              (self.c2.pk, "It's a test"),
              (self.c3.pk, 'Third')])
          with self.assertRaises(ValidationError):
              f.clean(None)
          with self.assertRaises(ValidationError):
              f.clean([])
          self.assertQuerysetEqual(f.clean([self.c1.id]), ["Entertainment"])
          self.assertQuerysetEqual(f.clean([self.c2.id]), ["It's a test"])
          self.assertQuerysetEqual(f.clean([str(self.c1.id)]), ["Entertainment"])
          self.assertQuerysetEqual(
              f.clean([str(self.c1.id), str(self.c2.id)]),
              ["Entertainment", "It's a test"], ordered=False
          )
          self.assertQuerysetEqual(
              f.clean([self.c1.id, str(self.c2.id)]),
              ["Entertainment", "It's a test"], ordered=False
          )
          self.assertQuerysetEqual(
              f.clean((self.c1.id, str(self.c2.id))),
              ["Entertainment", "It's a test"], ordered=False
          )
          with self.assertRaises(ValidationError):
              f.clean(['100'])
          with self.assertRaises(ValidationError):
              f.clean('hello')
          with self.assertRaises(ValidationError):
              f.clean(['fail'])
  
          # Invalid types that require TypeError to be caught (#22808).
          with self.assertRaises(ValidationError):
              f.clean([['fail']])
          with self.assertRaises(ValidationError):
              f.clean([{'foo': 'bar'}])
  
          # Add a Category object *after* the ModelMultipleChoiceField has already been
          # instantiated. This proves clean() checks the database during clean() rather
          # than caching it at time of instantiation.
          # Note, we are using an id of 1006 here since tests that run before
          # this may create categories with primary keys up to 6. Use
          # a number that will not conflict.
          c6 = Category.objects.create(id=1006, name='Sixth', url='6th')
          self.assertQuerysetEqual(f.clean([c6.id]), ["Sixth"])
  
          # Delete a Category object *after* the ModelMultipleChoiceField has already been
          # instantiated. This proves clean() checks the database during clean() rather
          # than caching it at time of instantiation.
          Category.objects.get(url='6th').delete()
          with self.assertRaises(ValidationError):
              f.clean([c6.id])
  
      def test_model_multiple_choice_required_false(self):
          f = forms.ModelMultipleChoiceField(Category.objects.all(), required=False)
          self.assertIsInstance(f.clean([]), EmptyQuerySet)
          self.assertIsInstance(f.clean(()), EmptyQuerySet)
          with self.assertRaises(ValidationError):
              f.clean(['0'])
          with self.assertRaises(ValidationError):
              f.clean([str(self.c3.id), '0'])
          with self.assertRaises(ValidationError):
              f.clean([str(self.c1.id), '0'])
  
          # queryset can be changed after the field is created.
          f.queryset = Category.objects.exclude(name='Third')
          self.assertEqual(list(f.choices), [
              (self.c1.pk, 'Entertainment'),
              (self.c2.pk, "It's a test")])
          self.assertQuerysetEqual(f.clean([self.c2.id]), ["It's a test"])
          with self.assertRaises(ValidationError):
              f.clean([self.c3.id])
          with self.assertRaises(ValidationError):
              f.clean([str(self.c2.id), str(self.c3.id)])
  
          f.queryset = Category.objects.all()
          f.label_from_instance = lambda obj: "multicategory " + str(obj)
          self.assertEqual(list(f.choices), [
              (self.c1.pk, 'multicategory Entertainment'),
              (self.c2.pk, "multicategory It's a test"),
              (self.c3.pk, 'multicategory Third')])
  
      def test_model_multiple_choice_number_of_queries(self):
          """
          Test that ModelMultipleChoiceField does O(1) queries instead of
          O(n) (#10156).
          """
          persons = [Writer.objects.create(name="Person %s" % i) for i in range(30)]
  
          f = forms.ModelMultipleChoiceField(queryset=Writer.objects.all())
          self.assertNumQueries(1, f.clean, [p.pk for p in persons[1:11:2]])
  
      def test_model_multiple_choice_run_validators(self):
          """
          Test that ModelMultipleChoiceField run given validators (#14144).
          """
          for i in range(30):
              Writer.objects.create(name="Person %s" % i)
  
          self._validator_run = False
  
          def my_validator(value):
              self._validator_run = True
  
          f = forms.ModelMultipleChoiceField(queryset=Writer.objects.all(),
                                             validators=[my_validator])
  
          f.clean([p.pk for p in Writer.objects.all()[8:9]])
          self.assertTrue(self._validator_run)
  
      def test_model_multiple_choice_show_hidden_initial(self):
          """
          Test support of show_hidden_initial by ModelMultipleChoiceField.
          """
          class WriterForm(forms.Form):
              persons = forms.ModelMultipleChoiceField(show_hidden_initial=True,
                                                       queryset=Writer.objects.all())
  
          person1 = Writer.objects.create(name="Person 1")
          person2 = Writer.objects.create(name="Person 2")
  
          form = WriterForm(initial={'persons': [person1, person2]},
                            data={'initial-persons': [str(person1.pk), str(person2.pk)],
                                  'persons': [str(person1.pk), str(person2.pk)]})
          self.assertTrue(form.is_valid())
          self.assertFalse(form.has_changed())
  
          form = WriterForm(initial={'persons': [person1, person2]},
                            data={'initial-persons': [str(person1.pk), str(person2.pk)],
                                  'persons': [str(person2.pk)]})
          self.assertTrue(form.is_valid())
          self.assertTrue(form.has_changed())
  
      def test_model_multiple_choice_field_22745(self):
          """
          #22745 -- Make sure that ModelMultipleChoiceField with
          CheckboxSelectMultiple widget doesn't produce unnecessary db queries
          when accessing its BoundField's attrs.
          """
          class ModelMultipleChoiceForm(forms.Form):
              categories = forms.ModelMultipleChoiceField(Category.objects.all(), widget=forms.CheckboxSelectMultiple)
  
          form = ModelMultipleChoiceForm()
          field = form['categories']  # BoundField
          template = Template('{{ field.name }}{{ field }}{{ field.help_text }}')
          with self.assertNumQueries(1):
              template.render(Context({'field': field}))
  
      def test_show_hidden_initial_changed_queries_efficiently(self):
          class WriterForm(forms.Form):
              persons = forms.ModelMultipleChoiceField(
                  show_hidden_initial=True, queryset=Writer.objects.all())
  
          writers = (Writer.objects.create(name=str(x)) for x in range(0, 50))
          writer_pks = tuple(x.pk for x in writers)
          form = WriterForm(data={'initial-persons': writer_pks})
          with self.assertNumQueries(1):
              self.assertTrue(form.has_changed())
  
      def test_clean_does_deduplicate_values(self):
          class WriterForm(forms.Form):
              persons = forms.ModelMultipleChoiceField(queryset=Writer.objects.all())
  
          person1 = Writer.objects.create(name="Person 1")
          form = WriterForm(data={})
          queryset = form.fields['persons'].clean([str(person1.pk)] * 50)
          sql, params = queryset.query.sql_with_params()
          self.assertEqual(len(params), 1)
  
  
  class ModelOneToOneFieldTests(TestCase):
      def test_modelform_onetoonefield(self):
          class ImprovedArticleForm(forms.ModelForm):
              class Meta:
                  model = ImprovedArticle
                  fields = '__all__'
  
          class ImprovedArticleWithParentLinkForm(forms.ModelForm):
              class Meta:
                  model = ImprovedArticleWithParentLink
                  fields = '__all__'
  
          self.assertEqual(list(ImprovedArticleForm.base_fields), ['article'])
          self.assertEqual(list(ImprovedArticleWithParentLinkForm.base_fields), [])
  
      def test_modelform_subclassed_model(self):
          class BetterWriterForm(forms.ModelForm):
              class Meta:
                  # BetterWriter model is a subclass of Writer with an additional `score` field
                  model = BetterWriter
                  fields = '__all__'
  
          bw = BetterWriter.objects.create(name='Joe Better', score=10)
          self.assertEqual(sorted(model_to_dict(bw)),
                           ['id', 'name', 'score', 'writer_ptr'])
  
          form = BetterWriterForm({'name': 'Some Name', 'score': 12})
          self.assertTrue(form.is_valid())
          bw2 = form.save()
          self.assertEqual(bw2.score, 12)
  
      def test_onetoonefield(self):
          class WriterProfileForm(forms.ModelForm):
              class Meta:
                  # WriterProfile has a OneToOneField to Writer
                  model = WriterProfile
                  fields = '__all__'
  
          self.w_royko = Writer.objects.create(name='Mike Royko')
          self.w_woodward = Writer.objects.create(name='Bob Woodward')
  
          form = WriterProfileForm()
          self.assertHTMLEqual(
              form.as_p(),
              '''<p><label for="id_writer">Writer:</label> <select name="writer" id="id_writer" required>
  <option value="" selected="selected">---------</option>
  <option value="%s">Bob Woodward</option>
  <option value="%s">Mike Royko</option>
  </select></p>
  <p><label for="id_age">Age:</label> <input type="number" name="age" id="id_age" min="0" required /></p>''' % (
                  self.w_woodward.pk, self.w_royko.pk,
              )
          )
  
          data = {
              'writer': six.text_type(self.w_woodward.pk),
              'age': '65',
          }
          form = WriterProfileForm(data)
          instance = form.save()
          self.assertEqual(six.text_type(instance), 'Bob Woodward is 65')
  
          form = WriterProfileForm(instance=instance)
          self.assertHTMLEqual(
              form.as_p(),
              '''<p><label for="id_writer">Writer:</label> <select name="writer" id="id_writer" required>
  <option value="">---------</option>
  <option value="%s" selected="selected">Bob Woodward</option>
  <option value="%s">Mike Royko</option>
  </select></p>
  <p><label for="id_age">Age:</label>
  <input type="number" name="age" value="65" id="id_age" min="0" required /></p>''' % (
                  self.w_woodward.pk, self.w_royko.pk,
              )
          )
  
      def test_assignment_of_none(self):
          class AuthorForm(forms.ModelForm):
              class Meta:
                  model = Author
                  fields = ['publication', 'full_name']
  
          publication = Publication.objects.create(title="Pravda", date_published=datetime.date(1991, 8, 22))
          author = Author.objects.create(publication=publication, full_name='John Doe')
          form = AuthorForm({'publication': '', 'full_name': 'John Doe'}, instance=author)
          self.assertTrue(form.is_valid())
          self.assertIsNone(form.cleaned_data['publication'])
          author = form.save()
          # author object returned from form still retains original publication object
          # that's why we need to retrieve it from database again
          new_author = Author.objects.get(pk=author.pk)
          self.assertIsNone(new_author.publication)
  
      def test_assignment_of_none_null_false(self):
          class AuthorForm(forms.ModelForm):
              class Meta:
                  model = Author1
                  fields = ['publication', 'full_name']
  
          publication = Publication.objects.create(title="Pravda", date_published=datetime.date(1991, 8, 22))
          author = Author1.objects.create(publication=publication, full_name='John Doe')
          form = AuthorForm({'publication': '', 'full_name': 'John Doe'}, instance=author)
          self.assertFalse(form.is_valid())
  
  
  class FileAndImageFieldTests(TestCase):
      def test_clean_false(self):
          """
          If the ``clean`` method on a non-required FileField receives False as
          the data (meaning clear the field value), it returns False, regardless
          of the value of ``initial``.
          """
          f = forms.FileField(required=False)
          self.assertIs(f.clean(False), False)
          self.assertIs(f.clean(False, 'initial'), False)
  
      def test_clean_false_required(self):
          """
          If the ``clean`` method on a required FileField receives False as the
          data, it has the same effect as None: initial is returned if non-empty,
          otherwise the validation catches the lack of a required value.
          """
          f = forms.FileField(required=True)
          self.assertEqual(f.clean(False, 'initial'), 'initial')
          with self.assertRaises(ValidationError):
              f.clean(False)
  
      def test_full_clear(self):
          """
          Integration happy-path test that a model FileField can actually be set
          and cleared via a ModelForm.
          """
          class DocumentForm(forms.ModelForm):
              class Meta:
                  model = Document
                  fields = '__all__'
  
          form = DocumentForm()
          self.assertIn('name="myfile"', six.text_type(form))
          self.assertNotIn('myfile-clear', six.text_type(form))
          form = DocumentForm(files={'myfile': SimpleUploadedFile('something.txt', b'content')})
          self.assertTrue(form.is_valid())
          doc = form.save(commit=False)
          self.assertEqual(doc.myfile.name, 'something.txt')
          form = DocumentForm(instance=doc)
          self.assertIn('myfile-clear', six.text_type(form))
          form = DocumentForm(instance=doc, data={'myfile-clear': 'true'})
          doc = form.save(commit=False)
          self.assertFalse(doc.myfile)
  
      def test_clear_and_file_contradiction(self):
          """
          If the user submits a new file upload AND checks the clear checkbox,
          they get a validation error, and the bound redisplay of the form still
          includes the current file and the clear checkbox.
          """
          class DocumentForm(forms.ModelForm):
              class Meta:
                  model = Document
                  fields = '__all__'
  
          form = DocumentForm(files={'myfile': SimpleUploadedFile('something.txt', b'content')})
          self.assertTrue(form.is_valid())
          doc = form.save(commit=False)
          form = DocumentForm(instance=doc,
                              files={'myfile': SimpleUploadedFile('something.txt', b'content')},
                              data={'myfile-clear': 'true'})
          self.assertTrue(not form.is_valid())
          self.assertEqual(form.errors['myfile'],
                           ['Please either submit a file or check the clear checkbox, not both.'])
          rendered = six.text_type(form)
          self.assertIn('something.txt', rendered)
          self.assertIn('myfile-clear', rendered)
  
      def test_render_empty_file_field(self):
          class DocumentForm(forms.ModelForm):
              class Meta:
                  model = Document
                  fields = '__all__'
  
          doc = Document.objects.create()
          form = DocumentForm(instance=doc)
          self.assertEqual(
              str(form['myfile']),
              '<input id="id_myfile" name="myfile" type="file" />'
          )
  
      def test_file_field_data(self):
          # Test conditions when files is either not given or empty.
          f = TextFileForm(data={'description': 'Assistance'})
          self.assertFalse(f.is_valid())
          f = TextFileForm(data={'description': 'Assistance'}, files={})
          self.assertFalse(f.is_valid())
  
          # Upload a file and ensure it all works as expected.
          f = TextFileForm(
              data={'description': 'Assistance'},
              files={'file': SimpleUploadedFile('test1.txt', b'hello world')})
          self.assertTrue(f.is_valid())
          self.assertEqual(type(f.cleaned_data['file']), SimpleUploadedFile)
          instance = f.save()
          self.assertEqual(instance.file.name, 'tests/test1.txt')
          instance.file.delete()
  
          # If the previous file has been deleted, the file name can be reused
          f = TextFileForm(
              data={'description': 'Assistance'},
              files={'file': SimpleUploadedFile('test1.txt', b'hello world')})
          self.assertTrue(f.is_valid())
          self.assertEqual(type(f.cleaned_data['file']), SimpleUploadedFile)
          instance = f.save()
          self.assertEqual(instance.file.name, 'tests/test1.txt')
  
          # Check if the max_length attribute has been inherited from the model.
          f = TextFileForm(
              data={'description': 'Assistance'},
              files={'file': SimpleUploadedFile('test-maxlength.txt', b'hello world')})
          self.assertFalse(f.is_valid())
  
          # Edit an instance that already has the file defined in the model. This will not
          # save the file again, but leave it exactly as it is.
          f = TextFileForm(
              data={'description': 'Assistance'},
              instance=instance)
          self.assertTrue(f.is_valid())
          self.assertEqual(f.cleaned_data['file'].name, 'tests/test1.txt')
          instance = f.save()
          self.assertEqual(instance.file.name, 'tests/test1.txt')
  
          # Delete the current file since this is not done by Django.
          instance.file.delete()
  
          # Override the file by uploading a new one.
          f = TextFileForm(
              data={'description': 'Assistance'},
              files={'file': SimpleUploadedFile('test2.txt', b'hello world')}, instance=instance)
          self.assertTrue(f.is_valid())
          instance = f.save()
          self.assertEqual(instance.file.name, 'tests/test2.txt')
  
          # Delete the current file since this is not done by Django.
          instance.file.delete()
          instance.delete()
  
      def test_filefield_required_false(self):
          # Test the non-required FileField
          f = TextFileForm(data={'description': 'Assistance'})
          f.fields['file'].required = False
          self.assertTrue(f.is_valid())
          instance = f.save()
          self.assertEqual(instance.file.name, '')
  
          f = TextFileForm(
              data={'description': 'Assistance'},
              files={'file': SimpleUploadedFile('test3.txt', b'hello world')}, instance=instance)
          self.assertTrue(f.is_valid())
          instance = f.save()
          self.assertEqual(instance.file.name, 'tests/test3.txt')
  
          # Instance can be edited w/out re-uploading the file and existing file should be preserved.
          f = TextFileForm(
              data={'description': 'New Description'},
              instance=instance)
          f.fields['file'].required = False
          self.assertTrue(f.is_valid())
          instance = f.save()
          self.assertEqual(instance.description, 'New Description')
          self.assertEqual(instance.file.name, 'tests/test3.txt')
  
          # Delete the current file since this is not done by Django.
          instance.file.delete()
          instance.delete()
  
      def test_custom_file_field_save(self):
          """
          Regression for #11149: save_form_data should be called only once
          """
          class CFFForm(forms.ModelForm):
              class Meta:
                  model = CustomFF
                  fields = '__all__'
  
          # It's enough that the form saves without error -- the custom save routine will
          # generate an AssertionError if it is called more than once during save.
          form = CFFForm(data={'f': None})
          form.save()
  
      def test_file_field_multiple_save(self):
          """
          Simulate a file upload and check how many times Model.save() gets
          called. Test for bug #639.
          """
          class PhotoForm(forms.ModelForm):
              class Meta:
                  model = Photo
                  fields = '__all__'
  
          # Grab an image for testing.
          filename = os.path.join(os.path.dirname(upath(__file__)), "test.png")
          with open(filename, "rb") as fp:
              img = fp.read()
  
          # Fake a POST QueryDict and FILES MultiValueDict.
          data = {'title': 'Testing'}
          files = {"image": SimpleUploadedFile('test.png', img, 'image/png')}
  
          form = PhotoForm(data=data, files=files)
          p = form.save()
  
          try:
              # Check the savecount stored on the object (see the model).
              self.assertEqual(p._savecount, 1)
          finally:
              # Delete the "uploaded" file to avoid clogging /tmp.
              p = Photo.objects.get()
              p.image.delete(save=False)
  
      def test_file_path_field_blank(self):
          """
          Regression test for #8842: FilePathField(blank=True)
          """
          class FPForm(forms.ModelForm):
              class Meta:
                  model = FilePathModel
                  fields = '__all__'
  
          form = FPForm()
          names = [p[1] for p in form['path'].field.choices]
          names.sort()
          self.assertEqual(names, ['---------', '__init__.py', 'models.py', 'test_uuid.py', 'tests.py'])
  
      @skipUnless(test_images, "Pillow not installed")
      def test_image_field(self):
          # ImageField and FileField are nearly identical, but they differ slightly when
          # it comes to validation. This specifically tests that #6302 is fixed for
          # both file fields and image fields.
  
          with open(os.path.join(os.path.dirname(upath(__file__)), "test.png"), 'rb') as fp:
              image_data = fp.read()
          with open(os.path.join(os.path.dirname(upath(__file__)), "test2.png"), 'rb') as fp:
              image_data2 = fp.read()
  
          f = ImageFileForm(
              data={'description': 'An image'},
              files={'image': SimpleUploadedFile('test.png', image_data)})
          self.assertTrue(f.is_valid())
          self.assertEqual(type(f.cleaned_data['image']), SimpleUploadedFile)
          instance = f.save()
          self.assertEqual(instance.image.name, 'tests/test.png')
          self.assertEqual(instance.width, 16)
          self.assertEqual(instance.height, 16)
  
          # Delete the current file since this is not done by Django, but don't save
          # because the dimension fields are not null=True.
          instance.image.delete(save=False)
          f = ImageFileForm(
              data={'description': 'An image'},
              files={'image': SimpleUploadedFile('test.png', image_data)})
          self.assertTrue(f.is_valid())
          self.assertEqual(type(f.cleaned_data['image']), SimpleUploadedFile)
          instance = f.save()
          self.assertEqual(instance.image.name, 'tests/test.png')
          self.assertEqual(instance.width, 16)
          self.assertEqual(instance.height, 16)
  
          # Edit an instance that already has the (required) image defined in the model. This will not
          # save the image again, but leave it exactly as it is.
  
          f = ImageFileForm(data={'description': 'Look, it changed'}, instance=instance)
          self.assertTrue(f.is_valid())
          self.assertEqual(f.cleaned_data['image'].name, 'tests/test.png')
          instance = f.save()
          self.assertEqual(instance.image.name, 'tests/test.png')
          self.assertEqual(instance.height, 16)
          self.assertEqual(instance.width, 16)
  
          # Delete the current file since this is not done by Django, but don't save
          # because the dimension fields are not null=True.
          instance.image.delete(save=False)
          # Override the file by uploading a new one.
  
          f = ImageFileForm(
              data={'description': 'Changed it'},
              files={'image': SimpleUploadedFile('test2.png', image_data2)}, instance=instance)
          self.assertTrue(f.is_valid())
          instance = f.save()
          self.assertEqual(instance.image.name, 'tests/test2.png')
          self.assertEqual(instance.height, 32)
          self.assertEqual(instance.width, 48)
  
          # Delete the current file since this is not done by Django, but don't save
          # because the dimension fields are not null=True.
          instance.image.delete(save=False)
          instance.delete()
  
          f = ImageFileForm(
              data={'description': 'Changed it'},
              files={'image': SimpleUploadedFile('test2.png', image_data2)})
          self.assertTrue(f.is_valid())
          instance = f.save()
          self.assertEqual(instance.image.name, 'tests/test2.png')
          self.assertEqual(instance.height, 32)
          self.assertEqual(instance.width, 48)
  
          # Delete the current file since this is not done by Django, but don't save
          # because the dimension fields are not null=True.
          instance.image.delete(save=False)
          instance.delete()
  
          # Test the non-required ImageField
          # Note: In Oracle, we expect a null ImageField to return '' instead of
          # None.
          if connection.features.interprets_empty_strings_as_nulls:
              expected_null_imagefield_repr = ''
          else:
              expected_null_imagefield_repr = None
  
          f = OptionalImageFileForm(data={'description': 'Test'})
          self.assertTrue(f.is_valid())
          instance = f.save()
          self.assertEqual(instance.image.name, expected_null_imagefield_repr)
          self.assertIsNone(instance.width)
          self.assertIsNone(instance.height)
  
          f = OptionalImageFileForm(
              data={'description': 'And a final one'},
              files={'image': SimpleUploadedFile('test3.png', image_data)}, instance=instance)
          self.assertTrue(f.is_valid())
          instance = f.save()
          self.assertEqual(instance.image.name, 'tests/test3.png')
          self.assertEqual(instance.width, 16)
          self.assertEqual(instance.height, 16)
  
          # Editing the instance without re-uploading the image should not affect
          # the image or its width/height properties.
          f = OptionalImageFileForm(
              data={'description': 'New Description'},
              instance=instance)
          self.assertTrue(f.is_valid())
          instance = f.save()
          self.assertEqual(instance.description, 'New Description')
          self.assertEqual(instance.image.name, 'tests/test3.png')
          self.assertEqual(instance.width, 16)
          self.assertEqual(instance.height, 16)
  
          # Delete the current file since this is not done by Django.
          instance.image.delete()
          instance.delete()
  
          f = OptionalImageFileForm(
              data={'description': 'And a final one'},
              files={'image': SimpleUploadedFile('test4.png', image_data2)}
          )
          self.assertTrue(f.is_valid())
          instance = f.save()
          self.assertEqual(instance.image.name, 'tests/test4.png')
          self.assertEqual(instance.width, 48)
          self.assertEqual(instance.height, 32)
          instance.delete()
          # Test callable upload_to behavior that's dependent on the value of another field in the model
          f = ImageFileForm(
              data={'description': 'And a final one', 'path': 'foo'},
              files={'image': SimpleUploadedFile('test4.png', image_data)})
          self.assertTrue(f.is_valid())
          instance = f.save()
          self.assertEqual(instance.image.name, 'foo/test4.png')
          instance.delete()
  
  
  class ModelOtherFieldTests(SimpleTestCase):
      def test_big_integer_field(self):
          bif = BigIntForm({'biggie': '-9223372036854775808'})
          self.assertTrue(bif.is_valid())
          bif = BigIntForm({'biggie': '-9223372036854775809'})
          self.assertFalse(bif.is_valid())
          self.assertEqual(
              bif.errors,
              {'biggie': ['Ensure this value is greater than or equal to -9223372036854775808.']}
          )
          bif = BigIntForm({'biggie': '9223372036854775807'})
          self.assertTrue(bif.is_valid())
          bif = BigIntForm({'biggie': '9223372036854775808'})
          self.assertFalse(bif.is_valid())
          self.assertEqual(bif.errors, {'biggie': ['Ensure this value is less than or equal to 9223372036854775807.']})
  
      def test_comma_separated_integer_field(self):
          class CommaSeparatedIntegerForm(forms.ModelForm):
              class Meta:
                  model = CommaSeparatedInteger
                  fields = '__all__'
  
          f = CommaSeparatedIntegerForm({'field': '1'})
          self.assertTrue(f.is_valid())
          self.assertEqual(f.cleaned_data, {'field': '1'})
          f = CommaSeparatedIntegerForm({'field': '12'})
          self.assertTrue(f.is_valid())
          self.assertEqual(f.cleaned_data, {'field': '12'})
          f = CommaSeparatedIntegerForm({'field': '1,2,3'})
          self.assertTrue(f.is_valid())
          self.assertEqual(f.cleaned_data, {'field': '1,2,3'})
          f = CommaSeparatedIntegerForm({'field': '10,32'})
          self.assertTrue(f.is_valid())
          self.assertEqual(f.cleaned_data, {'field': '10,32'})
          f = CommaSeparatedIntegerForm({'field': '1a,2'})
          self.assertEqual(f.errors, {'field': ['Enter only digits separated by commas.']})
          f = CommaSeparatedIntegerForm({'field': ',,,,'})
          self.assertEqual(f.errors, {'field': ['Enter only digits separated by commas.']})
          f = CommaSeparatedIntegerForm({'field': '1.2'})
          self.assertEqual(f.errors, {'field': ['Enter only digits separated by commas.']})
          f = CommaSeparatedIntegerForm({'field': '1,a,2'})
          self.assertEqual(f.errors, {'field': ['Enter only digits separated by commas.']})
          f = CommaSeparatedIntegerForm({'field': '1,,2'})
          self.assertEqual(f.errors, {'field': ['Enter only digits separated by commas.']})
  
      def test_url_on_modelform(self):
          "Check basic URL field validation on model forms"
          class HomepageForm(forms.ModelForm):
              class Meta:
                  model = Homepage
                  fields = '__all__'
  
          self.assertFalse(HomepageForm({'url': 'foo'}).is_valid())
          self.assertFalse(HomepageForm({'url': 'http://'}).is_valid())
          self.assertFalse(HomepageForm({'url': 'http://example'}).is_valid())
          self.assertFalse(HomepageForm({'url': 'http://example.'}).is_valid())
          self.assertFalse(HomepageForm({'url': 'http://com.'}).is_valid())
  
          self.assertTrue(HomepageForm({'url': 'http://localhost'}).is_valid())
          self.assertTrue(HomepageForm({'url': 'http://example.com'}).is_valid())
          self.assertTrue(HomepageForm({'url': 'http://www.example.com'}).is_valid())
          self.assertTrue(HomepageForm({'url': 'http://www.example.com:8000'}).is_valid())
          self.assertTrue(HomepageForm({'url': 'http://www.example.com/test'}).is_valid())
          self.assertTrue(HomepageForm({'url': 'http://www.example.com:8000/test'}).is_valid())
          self.assertTrue(HomepageForm({'url': 'http://example.com/foo/bar'}).is_valid())
  
      def test_modelform_non_editable_field(self):
          """
          When explicitly including a non-editable field in a ModelForm, the
          error message should be explicit.
          """
          # 'created', non-editable, is excluded by default
          self.assertNotIn('created', ArticleForm().fields)
  
          msg = "'created' cannot be specified for Article model form as it is a non-editable field"
          with self.assertRaisesMessage(FieldError, msg):
              class InvalidArticleForm(forms.ModelForm):
                  class Meta:
                      model = Article
                      fields = ('headline', 'created')
  
      def test_http_prefixing(self):
          """
          If the http:// prefix is omitted on form input, the field adds it again. (Refs #13613)
          """
          class HomepageForm(forms.ModelForm):
              class Meta:
                  model = Homepage
                  fields = '__all__'
  
          form = HomepageForm({'url': 'example.com'})
          self.assertTrue(form.is_valid())
          self.assertEqual(form.cleaned_data['url'], 'http://example.com')
  
          form = HomepageForm({'url': 'example.com/test'})
          self.assertTrue(form.is_valid())
          self.assertEqual(form.cleaned_data['url'], 'http://example.com/test')
  
  
  class OtherModelFormTests(TestCase):
      def test_media_on_modelform(self):
          # Similar to a regular Form class you can define custom media to be used on
          # the ModelForm.
          f = ModelFormWithMedia()
          self.assertHTMLEqual(
              six.text_type(f.media),
              '''<link href="/some/form/css" type="text/css" media="all" rel="stylesheet" />
  <script type="text/javascript" src="/some/form/javascript"></script>'''
          )
  
      def test_choices_type(self):
          # Choices on CharField and IntegerField
          f = ArticleForm()
          with self.assertRaises(ValidationError):
              f.fields['status'].clean('42')
  
          f = ArticleStatusForm()
          with self.assertRaises(ValidationError):
              f.fields['status'].clean('z')
  
      def test_prefetch_related_queryset(self):
          """
          ModelChoiceField should respect a prefetch_related() on its queryset.
          """
          blue = Colour.objects.create(name='blue')
          red = Colour.objects.create(name='red')
          multicolor_item = ColourfulItem.objects.create()
          multicolor_item.colours.add(blue, red)
          red_item = ColourfulItem.objects.create()
          red_item.colours.add(red)
  
          class ColorModelChoiceField(forms.ModelChoiceField):
              def label_from_instance(self, obj):
                  return ', '.join(c.name for c in obj.colours.all())
  
          field = ColorModelChoiceField(ColourfulItem.objects.prefetch_related('colours'))
          with self.assertNumQueries(4):  # would be 5 if prefetch is ignored
              self.assertEqual(tuple(field.choices), (
                  ('', '---------'),
                  (multicolor_item.pk, 'blue, red'),
                  (red_item.pk, 'red'),
              ))
  
      def test_foreignkeys_which_use_to_field(self):
          apple = Inventory.objects.create(barcode=86, name='Apple')
          Inventory.objects.create(barcode=22, name='Pear')
          core = Inventory.objects.create(barcode=87, name='Core', parent=apple)
  
          field = forms.ModelChoiceField(Inventory.objects.all(), to_field_name='barcode')
          self.assertEqual(tuple(field.choices), (
              ('', '---------'),
              (86, 'Apple'),
              (87, 'Core'),
              (22, 'Pear')))
  
          form = InventoryForm(instance=core)
          self.assertHTMLEqual(six.text_type(form['parent']), '''<select name="parent" id="id_parent">
  <option value="">---------</option>
  <option value="86" selected="selected">Apple</option>
  <option value="87">Core</option>
  <option value="22">Pear</option>
  </select>''')
          data = model_to_dict(core)
          data['parent'] = '22'
          form = InventoryForm(data=data, instance=core)
          core = form.save()
          self.assertEqual(core.parent.name, 'Pear')
  
          class CategoryForm(forms.ModelForm):
              description = forms.CharField()
  
              class Meta:
                  model = Category
                  fields = ['description', 'url']
  
          self.assertEqual(list(CategoryForm.base_fields),
                           ['description', 'url'])
  
          self.assertHTMLEqual(
              six.text_type(CategoryForm()),
              '''<tr><th><label for="id_description">Description:</label></th>
  <td><input type="text" name="description" id="id_description" required /></td></tr>
  <tr><th><label for="id_url">The URL:</label></th>
  <td><input id="id_url" type="text" name="url" maxlength="40" required /></td></tr>'''
          )
          # to_field_name should also work on ModelMultipleChoiceField ##################
  
          field = forms.ModelMultipleChoiceField(Inventory.objects.all(), to_field_name='barcode')
          self.assertEqual(tuple(field.choices), ((86, 'Apple'), (87, 'Core'), (22, 'Pear')))
          self.assertQuerysetEqual(field.clean([86]), ['Apple'])
  
          form = SelectInventoryForm({'items': [87, 22]})
          self.assertTrue(form.is_valid())
          self.assertEqual(len(form.cleaned_data), 1)
          self.assertQuerysetEqual(form.cleaned_data['items'], ['Core', 'Pear'])
  
      def test_model_field_that_returns_none_to_exclude_itself_with_explicit_fields(self):
          self.assertEqual(list(CustomFieldForExclusionForm.base_fields),
                           ['name'])
          self.assertHTMLEqual(
              six.text_type(CustomFieldForExclusionForm()),
              '''<tr><th><label for="id_name">Name:</label></th>
  <td><input id="id_name" type="text" name="name" maxlength="10" required /></td></tr>'''
          )
  
      def test_iterable_model_m2m(self):
          class ColourfulItemForm(forms.ModelForm):
              class Meta:
                  model = ColourfulItem
                  fields = '__all__'
  
          colour = Colour.objects.create(name='Blue')
          form = ColourfulItemForm()
          self.maxDiff = 1024
          self.assertHTMLEqual(
              form.as_p(),
              """<p><label for="id_name">Name:</label> <input id="id_name" type="text" name="name" maxlength="50" required /></p>
          <p><label for="id_colours">Colours:</label>
          <select multiple="multiple" name="colours" id="id_colours" required>
          <option value="%(blue_pk)s">Blue</option>
          </select></p>"""
              % {'blue_pk': colour.pk})
  
      def test_callable_field_default(self):
          class PublicationDefaultsForm(forms.ModelForm):
              class Meta:
                  model = PublicationDefaults
                  fields = '__all__'
  
          self.maxDiff = 2000
          form = PublicationDefaultsForm()
          today_str = str(datetime.date.today())
          self.assertHTMLEqual(
              form.as_p(),
              """
              <p><label for="id_title">Title:</label>
                  <input id="id_title" maxlength="30" name="title" type="text" required /></p>
              <p><label for="id_date_published">Date published:</label>
                  <input id="id_date_published" name="date_published" type="text" value="{0}" required />
                  <input id="initial-id_date_published" name="initial-date_published" type="hidden" value="{0}" /></p>
              <p><label for="id_mode">Mode:</label> <select id="id_mode" name="mode" required>
                  <option value="di" selected="selected">direct</option>
                  <option value="de">delayed</option></select>
                  <input id="initial-id_mode" name="initial-mode" type="hidden" value="di" /></p>
             <p><label for="id_category">Category:</label> <select id="id_category" name="category" required>
                  <option value="1">Games</option>
                  <option value="2">Comics</option>
                  <option value="3" selected="selected">Novel</option></select>
                  <input id="initial-id_category" name="initial-category" type="hidden" value="3" />
              """.format(today_str)
          )
          empty_data = {
              'title': '',
              'date_published': today_str,
              'initial-date_published': today_str,
              'mode': 'di',
              'initial-mode': 'di',
              'category': '3',
              'initial-category': '3',
          }
          bound_form = PublicationDefaultsForm(empty_data)
          self.assertFalse(bound_form.has_changed())
  
  
  class ModelFormCustomErrorTests(SimpleTestCase):
      def test_custom_error_messages(self):
          data = {'name1': '@#$!!**@#$', 'name2': '@#$!!**@#$'}
          errors = CustomErrorMessageForm(data).errors
          self.assertHTMLEqual(
              str(errors['name1']),
              '<ul class="errorlist"><li>Form custom error message.</li></ul>'
          )
          self.assertHTMLEqual(
              str(errors['name2']),
              '<ul class="errorlist"><li>Model custom error message.</li></ul>'
          )
  
      def test_model_clean_error_messages(self):
          data = {'name1': 'FORBIDDEN_VALUE', 'name2': 'ABC'}
          form = CustomErrorMessageForm(data)
          self.assertFalse(form.is_valid())
          self.assertHTMLEqual(
              str(form.errors['name1']),
              '<ul class="errorlist"><li>Model.clean() error messages.</li></ul>'
          )
          data = {'name1': 'FORBIDDEN_VALUE2', 'name2': 'ABC'}
          form = CustomErrorMessageForm(data)
          self.assertFalse(form.is_valid())
          self.assertHTMLEqual(
              str(form.errors['name1']),
              '<ul class="errorlist"><li>Model.clean() error messages (simpler syntax).</li></ul>'
          )
          data = {'name1': 'GLOBAL_ERROR', 'name2': 'ABC'}
          form = CustomErrorMessageForm(data)
          self.assertFalse(form.is_valid())
          self.assertEqual(form.errors['__all__'], ['Global error message.'])
  
  
  class CustomCleanTests(TestCase):
      def test_override_clean(self):
          """
          Regression for #12596: Calling super from ModelForm.clean() should be
          optional.
          """
          class TripleFormWithCleanOverride(forms.ModelForm):
              class Meta:
                  model = Triple
                  fields = '__all__'
  
              def clean(self):
                  if not self.cleaned_data['left'] == self.cleaned_data['right']:
                      raise forms.ValidationError('Left and right should be equal')
                  return self.cleaned_data
  
          form = TripleFormWithCleanOverride({'left': 1, 'middle': 2, 'right': 1})
          self.assertTrue(form.is_valid())
          # form.instance.left will be None if the instance was not constructed
          # by form.full_clean().
          self.assertEqual(form.instance.left, 1)
  
      def test_model_form_clean_applies_to_model(self):
          """
          Regression test for #12960. Make sure the cleaned_data returned from
          ModelForm.clean() is applied to the model instance.
          """
          class CategoryForm(forms.ModelForm):
              class Meta:
                  model = Category
                  fields = '__all__'
  
              def clean(self):
                  self.cleaned_data['name'] = self.cleaned_data['name'].upper()
                  return self.cleaned_data
  
          data = {'name': 'Test', 'slug': 'test', 'url': '/test'}
          form = CategoryForm(data)
          category = form.save()
          self.assertEqual(category.name, 'TEST')
  
  
  class ModelFormInheritanceTests(SimpleTestCase):
      def test_form_subclass_inheritance(self):
          class Form(forms.Form):
              age = forms.IntegerField()
  
          class ModelForm(forms.ModelForm, Form):
              class Meta:
                  model = Writer
                  fields = '__all__'
  
          self.assertEqual(list(ModelForm().fields.keys()), ['name', 'age'])
  
      def test_field_removal(self):
          class ModelForm(forms.ModelForm):
              class Meta:
                  model = Writer
                  fields = '__all__'
  
          class Mixin(object):
              age = None
  
          class Form(forms.Form):
              age = forms.IntegerField()
  
          class Form2(forms.Form):
              foo = forms.IntegerField()
  
          self.assertEqual(list(ModelForm().fields.keys()), ['name'])
          self.assertEqual(list(type(str('NewForm'), (Mixin, Form), {})().fields.keys()), [])
          self.assertEqual(list(type(str('NewForm'), (Form2, Mixin, Form), {})().fields.keys()), ['foo'])
          self.assertEqual(list(type(str('NewForm'), (Mixin, ModelForm, Form), {})().fields.keys()), ['name'])
          self.assertEqual(list(type(str('NewForm'), (ModelForm, Mixin, Form), {})().fields.keys()), ['name'])
          self.assertEqual(list(type(str('NewForm'), (ModelForm, Form, Mixin), {})().fields.keys()), ['name', 'age'])
          self.assertEqual(list(type(str('NewForm'), (ModelForm, Form), {'age': None})().fields.keys()), ['name'])
  
      def test_field_removal_name_clashes(self):
          """Regression test for https://code.djangoproject.com/ticket/22510."""
  
          class MyForm(forms.ModelForm):
              media = forms.CharField()
  
              class Meta:
                  model = Writer
                  fields = '__all__'
  
          class SubForm(MyForm):
              media = None
  
          self.assertIn('media', MyForm().fields)
          self.assertNotIn('media', SubForm().fields)
          self.assertTrue(hasattr(MyForm, 'media'))
          self.assertTrue(hasattr(SubForm, 'media'))
  
  
  class StumpJokeForm(forms.ModelForm):
      class Meta:
          model = StumpJoke
          fields = '__all__'
  
  
  class CustomFieldWithQuerysetButNoLimitChoicesTo(forms.Field):
      queryset = 42
  
  
  class StumpJokeWithCustomFieldForm(forms.ModelForm):
      custom = CustomFieldWithQuerysetButNoLimitChoicesTo()
  
      class Meta:
          model = StumpJoke
          fields = ()  # We don't need any fields from the model
  
  
  class LimitChoicesToTest(TestCase):
      """
      Tests the functionality of ``limit_choices_to``.
      """
      def setUp(self):
          self.threepwood = Character.objects.create(
              username='threepwood',
              last_action=datetime.datetime.today() + datetime.timedelta(days=1),
          )
          self.marley = Character.objects.create(
              username='marley',
              last_action=datetime.datetime.today() - datetime.timedelta(days=1),
          )
  
      def test_limit_choices_to_callable_for_fk_rel(self):
          """
          A ForeignKey relation can use ``limit_choices_to`` as a callable, re #2554.
          """
          stumpjokeform = StumpJokeForm()
          self.assertIn(self.threepwood, stumpjokeform.fields['most_recently_fooled'].queryset)
          self.assertNotIn(self.marley, stumpjokeform.fields['most_recently_fooled'].queryset)
  
      def test_limit_choices_to_callable_for_m2m_rel(self):
          """
          A ManyToMany relation can use ``limit_choices_to`` as a callable, re #2554.
          """
          stumpjokeform = StumpJokeForm()
          self.assertIn(self.threepwood, stumpjokeform.fields['has_fooled_today'].queryset)
          self.assertNotIn(self.marley, stumpjokeform.fields['has_fooled_today'].queryset)
  
      def test_custom_field_with_queryset_but_no_limit_choices_to(self):
          """
          Regression test for #23795: Make sure a custom field with a `queryset`
          attribute but no `limit_choices_to` still works.
          """
          f = StumpJokeWithCustomFieldForm()
          self.assertEqual(f.fields['custom'].queryset, 42)
  
  
  class FormFieldCallbackTests(SimpleTestCase):
  
      def test_baseform_with_widgets_in_meta(self):
          """Regression for #13095: Using base forms with widgets defined in Meta should not raise errors."""
          widget = forms.Textarea()
  
          class BaseForm(forms.ModelForm):
              class Meta:
                  model = Person
                  widgets = {'name': widget}
                  fields = "__all__"
  
          Form = modelform_factory(Person, form=BaseForm)
          self.assertIs(Form.base_fields['name'].widget, widget)
  
      def test_factory_with_widget_argument(self):
          """ Regression for #15315: modelform_factory should accept widgets
              argument
          """
          widget = forms.Textarea()
  
          # Without a widget should not set the widget to textarea
          Form = modelform_factory(Person, fields="__all__")
          self.assertNotEqual(Form.base_fields['name'].widget.__class__, forms.Textarea)
  
          # With a widget should not set the widget to textarea
          Form = modelform_factory(Person, fields="__all__", widgets={'name': widget})
          self.assertEqual(Form.base_fields['name'].widget.__class__, forms.Textarea)
  
      def test_modelform_factory_without_fields(self):
          """ Regression for #19733 """
          message = (
              "Calling modelform_factory without defining 'fields' or 'exclude' "
              "explicitly is prohibited."
          )
          with self.assertRaisesMessage(ImproperlyConfigured, message):
              modelform_factory(Person)
  
      def test_modelform_factory_with_all_fields(self):
          """ Regression for #19733 """
          form = modelform_factory(Person, fields="__all__")
          self.assertEqual(list(form.base_fields), ["name"])
  
      def test_custom_callback(self):
          """Test that a custom formfield_callback is used if provided"""
  
          callback_args = []
  
          def callback(db_field, **kwargs):
              callback_args.append((db_field, kwargs))
              return db_field.formfield(**kwargs)
  
          widget = forms.Textarea()
  
          class BaseForm(forms.ModelForm):
              class Meta:
                  model = Person
                  widgets = {'name': widget}
                  fields = "__all__"
  
          modelform_factory(Person, form=BaseForm, formfield_callback=callback)
          id_field, name_field = Person._meta.fields
  
          self.assertEqual(callback_args,
                           [(id_field, {}), (name_field, {'widget': widget})])
  
      def test_bad_callback(self):
          # A bad callback provided by user still gives an error
          with self.assertRaises(TypeError):
              modelform_factory(Person, fields="__all__", formfield_callback='not a function or callable')
  
      def test_inherit_after_custom_callback(self):
          def callback(db_field, **kwargs):
              if isinstance(db_field, models.CharField):
                  return forms.CharField(widget=forms.Textarea)
              return db_field.formfield(**kwargs)
  
          class BaseForm(forms.ModelForm):
              class Meta:
                  model = Person
                  fields = '__all__'
  
          NewForm = modelform_factory(Person, form=BaseForm, formfield_callback=callback)
  
          class InheritedForm(NewForm):
              pass
  
          for name in NewForm.base_fields.keys():
              self.assertEqual(
                  type(InheritedForm.base_fields[name].widget),
                  type(NewForm.base_fields[name].widget)
              )
  
  
  class LocalizedModelFormTest(TestCase):
      def test_model_form_applies_localize_to_some_fields(self):
          class PartiallyLocalizedTripleForm(forms.ModelForm):
              class Meta:
                  model = Triple
                  localized_fields = ('left', 'right',)
                  fields = '__all__'
  
          f = PartiallyLocalizedTripleForm({'left': 10, 'middle': 10, 'right': 10})
          self.assertTrue(f.is_valid())
          self.assertTrue(f.fields['left'].localize)
          self.assertFalse(f.fields['middle'].localize)
          self.assertTrue(f.fields['right'].localize)
  
      def test_model_form_applies_localize_to_all_fields(self):
          class FullyLocalizedTripleForm(forms.ModelForm):
              class Meta:
                  model = Triple
                  localized_fields = '__all__'
                  fields = '__all__'
  
          f = FullyLocalizedTripleForm({'left': 10, 'middle': 10, 'right': 10})
          self.assertTrue(f.is_valid())
          self.assertTrue(f.fields['left'].localize)
          self.assertTrue(f.fields['middle'].localize)
          self.assertTrue(f.fields['right'].localize)
  
      def test_model_form_refuses_arbitrary_string(self):
          with self.assertRaises(TypeError):
              class BrokenLocalizedTripleForm(forms.ModelForm):
                  class Meta:
                      model = Triple
                      localized_fields = "foo"
  
  
  class CustomMetaclass(ModelFormMetaclass):
      def __new__(cls, name, bases, attrs):
          new = super(CustomMetaclass, cls).__new__(cls, name, bases, attrs)
          new.base_fields = {}
          return new
  
  
  class CustomMetaclassForm(six.with_metaclass(CustomMetaclass, forms.ModelForm)):
      pass
  
  
  class CustomMetaclassTestCase(SimpleTestCase):
      def test_modelform_factory_metaclass(self):
          new_cls = modelform_factory(Person, fields="__all__", form=CustomMetaclassForm)
          self.assertEqual(new_cls.base_fields, {})
  
  
  class StrictAssignmentTests(TestCase):
      """
      Should a model do anything special with __setattr__() or descriptors which
      raise a ValidationError, a model form should catch the error (#24706).
      """
  
      def test_setattr_raises_validation_error_field_specific(self):
          """
          A model ValidationError using the dict form should put the error
          message into the correct key of form.errors.
          """
          form_class = modelform_factory(model=StrictAssignmentFieldSpecific, fields=['title'])
          form = form_class(data={'title': 'testing setattr'}, files=None)
          # This line turns on the ValidationError; it avoids the model erroring
          # when its own __init__() is called when creating form.instance.
          form.instance._should_error = True
          self.assertFalse(form.is_valid())
          self.assertEqual(form.errors, {
              'title': ['Cannot set attribute', 'This field cannot be blank.']
          })
  
      def test_setattr_raises_validation_error_non_field(self):
          """
          A model ValidationError not using the dict form should put the error
          message into __all__ (i.e. non-field errors) on the form.
          """
          form_class = modelform_factory(model=StrictAssignmentAll, fields=['title'])
          form = form_class(data={'title': 'testing setattr'}, files=None)
          # This line turns on the ValidationError; it avoids the model erroring
          # when its own __init__() is called when creating form.instance.
          form.instance._should_error = True
          self.assertFalse(form.is_valid())
          self.assertEqual(form.errors, {
              '__all__': ['Cannot set attribute'],
              'title': ['This field cannot be blank.']
          })
  