Ticket #14119: fix-14119.diff

django/forms/models.py

@@ -39 +39 @@
         if not f.editable or isinstance(f, models.AutoField) \
                 or not f.name in cleaned_data:
             continue
-        if fields and f.name not in fields:
+        if fields is not None and f.name not in fields:
             continue
         if exclude and f.name in exclude:
             continue
@@ -167 +167 @@
     for f in opts.fields + opts.many_to_many:
         if not f.editable:
             continue
-        if fields and not f.name in fields:
+        if fields is not None and not f.name in fields:
             continue
         if exclude and f.name in exclude:
             continue

tests/regressiontests/model_forms_regress/tests.py

@@ -2 +2 @@
 
 from django import db
 from django import forms
-from django.forms.models import modelform_factory, ModelChoiceField
+from django.forms.models import modelform_factory, ModelChoiceField, fields_for_model, construct_instance
 from django.conf import settings
 from django.test import TestCase
 
@@ -250 +250 @@
         form.is_valid()
         # self.assertTrue(form.is_valid())
         # self.assertEquals(form.cleaned_data['url'], 'http://example.com/test')
+
+class EmptyFieldsTestCase(TestCase):
+    "Tests for fields=() cases as reported in #14119"
+    class EmptyPersonForm(forms.ModelForm):
+        class Meta:
+            model = Person
+            fields = ()
+
+    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"
+        form = self.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)({'name': 'John Doe'})
+        self.assertTrue(form.is_valid())
+        instance = construct_instance(form, Person(), fields=())
+        self.assertEqual(instance.name, '')

tests/regressiontests/model_formsets_regress/tests.py

@@ -1 @@
-from django.forms.models import modelform_factory, inlineformset_factory
+from django.forms.models import modelform_factory, modelformset_factory, inlineformset_factory
 from django.test import TestCase
 
 from models import User, UserSite, Restaurant, Manager
@@ -156 +156 @@
         # you can create a formset with an instance of None
         form = Form(instance=None)
         formset = FormSet(instance=None)
+
+    def test_empty_fields_on_modelformset(self):
+        "No fields passed to modelformset_factory should result in no fields on returned forms except for the id. See #14119."
+        UserFormSet = modelformset_factory(User, fields=())
+        formset = UserFormSet()
+        for form in formset.forms:
+            self.assertTrue('id' in form.fields)
+            self.assertEqual(len(form.fields), 1)