Consolidated ModelChoiceField tests.

2 files changed, 277 insertions, 258 deletions

diff --git a/tests/model_forms/test_modelchoicefield.py b/tests/model_forms/test_modelchoicefield.py
new file mode 100644
index 0000000000..057eb0d25b
--- /dev/null
+++ b/tests/model_forms/test_modelchoicefield.py
@@ -0,0 +1,275 @@
+import datetime
+
+from django import forms
+from django.core.validators import ValidationError
+from django.forms.models import ModelChoiceIterator
+from django.forms.widgets import CheckboxSelectMultiple
+from django.template import Context, Template
+from django.test import TestCase
+
+from .models import Article, Author, Book, Category, Writer
+
+
+class ModelChoiceFieldTests(TestCase):
+    @classmethod
+    def setUpTestData(cls):
+        cls.c1 = Category.objects.create(name='Entertainment', slug='entertainment', url='entertainment')
+        cls.c2 = Category.objects.create(name='A test', slug='test', url='test')
+        cls.c3 = Category.objects.create(name='Third', slug='third-test', url='third')
+
+    def test_basics(self):
+        f = forms.ModelChoiceField(Category.objects.all())
+        self.assertEqual(list(f.choices), [
+            ('', '---------'),
+            (self.c1.pk, 'Entertainment'),
+            (self.c2.pk, '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.
+        with self.assertRaises(ValidationError):
+            f.clean([['fail']])
+        with self.assertRaises(ValidationError):
+            f.clean([{'foo': 'bar'}])
+
+        self.assertEqual(f.clean(self.c2.id).name, '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  instantiation time.
+        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 instantiation time.
+        Category.objects.get(url='4th').delete()
+        msg = "['Select a valid choice. That choice is not one of the available choices.']"
+        with self.assertRaisesMessage(ValidationError, msg):
+            f.clean(c4.id)
+
+    def test_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, 'A test'),
+        ])
+        self.assertEqual(f.clean(self.c2.id).name, 'A test')
+        with self.assertRaises(ValidationError):
+            f.clean(self.c3.id)
+
+        # Choices can be iterated repeatedly.
+        gen_one = list(f.choices)
+        gen_two = f.choices
+        self.assertEqual(gen_one[2], (self.c2.pk, 'A test'))
+        self.assertEqual(list(gen_two), [
+            ('', '---------'),
+            (self.c1.pk, 'Entertainment'),
+            (self.c2.pk, 'A test'),
+        ])
+
+        # Overriding label_from_instance() to print custom labels.
+        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 A test'),
+            (self.c3.pk, 'category Third'),
+        ])
+
+    def test_deepcopies_widget(self):
+        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
+        # without affecting other forms, the following must hold (#11183):
+        self.assertIsNot(field1, ModelChoiceForm.base_fields['category'])
+        self.assertIs(field1.widget.choices.field, field1)
+
+    def test_result_cache_not_shared(self):
+        class ModelChoiceForm(forms.Form):
+            category = forms.ModelChoiceField(Category.objects.all())
+
+        form1 = ModelChoiceForm()
+        self.assertCountEqual(form1.fields['category'].queryset, [self.c1, self.c2, self.c3])
+        form2 = ModelChoiceForm()
+        self.assertIsNone(form2.fields['category'].queryset._result_cache)
+
+    def test_queryset_none(self):
+        class ModelChoiceForm(forms.Form):
+            category = forms.ModelChoiceField(queryset=None)
+
+            def __init__(self, *args, **kwargs):
+                super().__init__(*args, **kwargs)
+                self.fields['category'].queryset = Category.objects.filter(slug__contains='test')
+
+        form = ModelChoiceForm()
+        self.assertCountEqual(form.fields['category'].queryset, [self.c2, self.c3])
+
+    def test_no_extra_query_when_accessing_attrs(self):
+        """
+        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_disabled_modelchoicefield(self):
+        class ModelChoiceForm(forms.ModelForm):
+            author = forms.ModelChoiceField(Author.objects.all(), disabled=True)
+
+            class Meta:
+                model = Book
+                fields = ['author']
+
+        book = Book.objects.create(author=Writer.objects.create(name='Test writer'))
+        form = ModelChoiceForm({}, instance=book)
+        self.assertEqual(
+            form.errors['author'],
+            ['Select a valid choice. That choice is not one of the available choices.']
+        )
+
+    def test_disabled_modelchoicefield_has_changed(self):
+        field = forms.ModelChoiceField(Author.objects.all(), disabled=True)
+        self.assertIs(field.has_changed('x', 'y'), False)
+
+    def test_disabled_multiplemodelchoicefield(self):
+        class ArticleForm(forms.ModelForm):
+            categories = forms.ModelMultipleChoiceField(Category.objects.all(), required=False)
+
+            class Meta:
+                model = Article
+                fields = ['categories']
+
+        category1 = Category.objects.create(name='cat1')
+        category2 = Category.objects.create(name='cat2')
+        article = Article.objects.create(
+            pub_date=datetime.date(1988, 1, 4),
+            writer=Writer.objects.create(name='Test writer'),
+        )
+        article.categories.set([category1.pk])
+
+        form = ArticleForm(data={'categories': [category2.pk]}, instance=article)
+        self.assertEqual(form.errors, {})
+        self.assertEqual([x.pk for x in form.cleaned_data['categories']], [category2.pk])
+        # Disabled fields use the value from `instance` rather than `data`.
+        form = ArticleForm(data={'categories': [category2.pk]}, instance=article)
+        form.fields['categories'].disabled = True
+        self.assertEqual(form.errors, {})
+        self.assertEqual([x.pk for x in form.cleaned_data['categories']], [category1.pk])
+
+    def test_disabled_modelmultiplechoicefield_has_changed(self):
+        field = forms.ModelMultipleChoiceField(Author.objects.all(), disabled=True)
+        self.assertIs(field.has_changed('x', 'y'), False)
+
+    def test_overridable_choice_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)
+
+    def test_choice_iterator_passes_model_to_widget(self):
+        class CustomModelChoiceValue:
+            def __init__(self, value, obj):
+                self.value = value
+                self.obj = obj
+
+            def __str__(self):
+                return str(self.value)
+
+        class CustomModelChoiceIterator(ModelChoiceIterator):
+            def choice(self, obj):
+                value, label = super().choice(obj)
+                return CustomModelChoiceValue(value, obj), label
+
+        class CustomCheckboxSelectMultiple(CheckboxSelectMultiple):
+            def create_option(self, name, value, label, selected, index, subindex=None, attrs=None):
+                option = super().create_option(name, value, label, selected, index, subindex=None, attrs=None)
+                # Modify the HTML based on the object being rendered.
+                c = value.obj
+                option['attrs']['data-slug'] = c.slug
+                return option
+
+        class CustomModelMultipleChoiceField(forms.ModelMultipleChoiceField):
+            iterator = CustomModelChoiceIterator
+            widget = CustomCheckboxSelectMultiple
+
+        field = CustomModelMultipleChoiceField(Category.objects.all())
+        self.assertHTMLEqual(
+            field.widget.render('name', []),
+            '''<ul>
+<li><label><input type="checkbox" name="name" value="%d" data-slug="entertainment">Entertainment</label></li>
+<li><label><input type="checkbox" name="name" value="%d" data-slug="test">A test</label></li>
+<li><label><input type="checkbox" name="name" value="%d" data-slug="third-test">Third</label></li>
+</ul>''' % (self.c1.pk, self.c2.pk, self.c3.pk),
+        )
+
+    def test_choices_not_fetched_when_not_rendering(self):
+        with self.assertNumQueries(1):
+            field = forms.ModelChoiceField(Category.objects.order_by('-name'))
+            self.assertEqual('Entertainment', field.clean(self.c1.pk).name)
+
+    def test_queryset_manager(self):
+        f = forms.ModelChoiceField(Category.objects)
+        self.assertEqual(list(f.choices), [
+            ('', '---------'),
+            (self.c1.pk, 'Entertainment'),
+            (self.c2.pk, 'A test'),
+            (self.c3.pk, 'Third'),
+        ])
+
+    def test_num_queries(self):
+        """
+        Widgets that render multiple subwidgets shouldn't make more than one
+        database query.
+        """
+        categories = Category.objects.all()
+
+        class CategoriesForm(forms.Form):
+            radio = forms.ModelChoiceField(queryset=categories, widget=forms.RadioSelect)
+            checkbox = forms.ModelMultipleChoiceField(queryset=categories, widget=forms.CheckboxSelectMultiple)
+
+        template = Template(
+            '{% for widget in form.checkbox %}{{ widget }}{% endfor %}'
+            '{% for widget in form.radio %}{{ widget }}{% endfor %}'
+        )
+        with self.assertNumQueries(2):
+            template.render(Context({'form': CategoriesForm()}))
diff --git a/tests/model_forms/tests.py b/tests/model_forms/tests.py
index 9b991d209d..fced7403ba 100644
--- a/tests/model_forms/tests.py
+++ b/tests/model_forms/tests.py
@@ -12,10 +12,9 @@ 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,
+    ModelFormMetaclass, construct_instance, fields_for_model, model_to_dict,
+    modelform_factory,
 )
-from django.forms.widgets import CheckboxSelectMultiple
 from django.template import Context, Template
 from django.test import SimpleTestCase, TestCase, skipUnlessDBFeature
 
@@ -1557,261 +1556,6 @@ class ModelFormBasicTests(TestCase):
         obj.full_clean()
 
 
-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()
-        msg = "['Select a valid choice. That choice is not one of the available choices.']"
-        with self.assertRaisesMessage(ValidationError, msg):
-            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_result_cache_not_shared(self):
-        class ModelChoiceForm(forms.Form):
-            category = forms.ModelChoiceField(Category.objects.all())
-
-        form1 = ModelChoiceForm()
-        self.assertCountEqual(form1.fields['category'].queryset, [self.c1, self.c2, self.c3])
-        form2 = ModelChoiceForm()
-        self.assertIsNone(form2.fields['category'].queryset._result_cache)
-
-    def test_modelchoicefield_queryset_none(self):
-        class ModelChoiceForm(forms.Form):
-            category = forms.ModelChoiceField(queryset=None)
-
-            def __init__(self, *args, **kwargs):
-                super().__init__(*args, **kwargs)
-                self.fields['category'].queryset = Category.objects.filter(slug__contains='test')
-
-        form = ModelChoiceForm()
-        self.assertCountEqual(form.fields['category'].queryset, [self.c2, self.c3])
-
-    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_disabled_modelchoicefield(self):
-        class ModelChoiceForm(forms.ModelForm):
-            author = forms.ModelChoiceField(Author.objects.all(), disabled=True)
-
-            class Meta:
-                model = Book
-                fields = ['author']
-
-        book = Book.objects.create(author=Writer.objects.create(name='Test writer'))
-        form = ModelChoiceForm({}, instance=book)
-        self.assertEqual(
-            form.errors['author'],
-            ['Select a valid choice. That choice is not one of the available choices.']
-        )
-
-    def test_disabled_modelchoicefield_has_changed(self):
-        field = forms.ModelChoiceField(Author.objects.all(), disabled=True)
-        self.assertIs(field.has_changed('x', 'y'), False)
-
-    def test_disabled_multiplemodelchoicefield(self):
-        class ArticleForm(forms.ModelForm):
-            categories = forms.ModelMultipleChoiceField(Category.objects.all(), required=False)
-
-            class Meta:
-                model = Article
-                fields = ['categories']
-
-        category1 = Category.objects.create(name='cat1')
-        category2 = Category.objects.create(name='cat2')
-        article = Article.objects.create(
-            pub_date=datetime.date(1988, 1, 4),
-            writer=Writer.objects.create(name='Test writer'),
-        )
-        article.categories.set([category1.pk])
-
-        form = ArticleForm(data={'categories': [category2.pk]}, instance=article)
-        self.assertEqual(form.errors, {})
-        self.assertEqual([x.pk for x in form.cleaned_data['categories']], [category2.pk])
-        # Disabled fields use the value from `instance` rather than `data`.
-        form = ArticleForm(data={'categories': [category2.pk]}, instance=article)
-        form.fields['categories'].disabled = True
-        self.assertEqual(form.errors, {})
-        self.assertEqual([x.pk for x in form.cleaned_data['categories']], [category1.pk])
-
-    def test_disabled_modelmultiplechoicefield_has_changed(self):
-        field = forms.ModelMultipleChoiceField(Author.objects.all(), disabled=True)
-        self.assertIs(field.has_changed('x', 'y'), False)
-
-    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)
-
-    def test_modelchoicefield_iterator_pass_model_to_widget(self):
-        class CustomModelChoiceValue:
-            def __init__(self, value, obj):
-                self.value = value
-                self.obj = obj
-
-            def __str__(self):
-                return str(self.value)
-
-        class CustomModelChoiceIterator(ModelChoiceIterator):
-            def choice(self, obj):
-                value, label = super().choice(obj)
-                return CustomModelChoiceValue(value, obj), label
-
-        class CustomCheckboxSelectMultiple(CheckboxSelectMultiple):
-            def create_option(self, name, value, label, selected, index, subindex=None, attrs=None):
-                option = super().create_option(name, value, label, selected, index, subindex=None, attrs=None)
-                # Modify the HTML based on the object being rendered.
-                c = value.obj
-                option['attrs']['data-slug'] = c.slug
-                return option
-
-        class CustomModelMultipleChoiceField(forms.ModelMultipleChoiceField):
-            iterator = CustomModelChoiceIterator
-            widget = CustomCheckboxSelectMultiple
-
-        field = CustomModelMultipleChoiceField(Category.objects.all())
-        self.assertHTMLEqual(
-            field.widget.render('name', []),
-            '''<ul>
-<li><label><input type="checkbox" name="name" value="%d" data-slug="entertainment">Entertainment</label></li>
-<li><label><input type="checkbox" name="name" value="%d" data-slug="its-test">It&#39;s a test</label></li>
-<li><label><input type="checkbox" name="name" value="%d" data-slug="third-test">Third</label></li>
-</ul>''' % (self.c1.pk, self.c2.pk, self.c3.pk),
-        )
-
-    def test_modelchoicefield_num_queries(self):
-        """
-        Widgets that render multiple subwidgets shouldn't make more than one
-        database query.
-        """
-        categories = Category.objects.all()
-
-        class CategoriesForm(forms.Form):
-            radio = forms.ModelChoiceField(queryset=categories, widget=forms.RadioSelect)
-            checkbox = forms.ModelMultipleChoiceField(queryset=categories, widget=forms.CheckboxSelectMultiple)
-
-        template = Template("""
-            {% for widget in form.checkbox %}{{ widget }}{% endfor %}
-            {% for widget in form.radio %}{{ widget }}{% endfor %}
-        """)
-
-        with self.assertNumQueries(2):
-            template.render(Context({'form': CategoriesForm()}))
-
-
 class ModelMultipleChoiceFieldTests(TestCase):
     def setUp(self):
         self.c1 = Category.objects.create(