[1.2.X] Fixed #13095 -- formfield_callback keyword argument is now more sane and works with widgets defined in ModelForm.Meta.widgets. Thanks, hvdklauw for bug report, vung for initial patch, and carljm for review. Backport of r13730 from trunk.

git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.2.X@13731 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/forms/models.py

@@ -150,7 +150,7 @@ def model_to_dict(instance, fields=None, exclude=None):
             data[f.name] = f.value_from_object(instance)
     return data
 
-def fields_for_model(model, fields=None, exclude=None, widgets=None, formfield_callback=lambda f, **kwargs: f.formfield(**kwargs)):
+def fields_for_model(model, fields=None, exclude=None, widgets=None, formfield_callback=None):
     """
     Returns a ``SortedDict`` containing form fields for the given model.
 
@@ -175,7 +175,14 @@ def fields_for_model(model, fields=None, exclude=None, widgets=None, formfield_c
             kwargs = {'widget': widgets[f.name]}
         else:
             kwargs = {}
-        formfield = formfield_callback(f, **kwargs)
+
+        if formfield_callback is None:
+            formfield = f.formfield(**kwargs)
+        elif not callable(formfield_callback):
+            raise TypeError('formfield_callback must be a function or callable')
+        else:
+            formfield = formfield_callback(f, **kwargs)
+
         if formfield:
             field_list.append((f.name, formfield))
         else:
@@ -198,8 +205,7 @@ class ModelFormOptions(object):
 
 class ModelFormMetaclass(type):
     def __new__(cls, name, bases, attrs):
-        formfield_callback = attrs.pop('formfield_callback',
-                lambda f, **kwargs: f.formfield(**kwargs))
+        formfield_callback = attrs.pop('formfield_callback', None)
         try:
             parents = [b for b in bases if issubclass(b, ModelForm)]
         except NameError:
@@ -376,7 +382,7 @@ class ModelForm(BaseModelForm):
     __metaclass__ = ModelFormMetaclass
 
 def modelform_factory(model, form=ModelForm, fields=None, exclude=None,
-                       formfield_callback=lambda f: f.formfield()):
+                       formfield_callback=None):
     # Create the inner Meta class. FIXME: ideally, we should be able to
     # construct a ModelForm without creating and passing in a temporary
     # inner class.
@@ -658,7 +664,7 @@ class BaseModelFormSet(BaseFormSet):
             form.fields[self._pk_field.name] = ModelChoiceField(qs, initial=pk_value, required=False, widget=HiddenInput)
         super(BaseModelFormSet, self).add_fields(form, index)
 
-def modelformset_factory(model, form=ModelForm, formfield_callback=lambda f: f.formfield(),
+def modelformset_factory(model, form=ModelForm, formfield_callback=None,
                          formset=BaseModelFormSet,
                          extra=1, can_delete=False, can_order=False,
                          max_num=None, fields=None, exclude=None):
@@ -813,7 +819,7 @@ def inlineformset_factory(parent_model, model, form=ModelForm,
                           formset=BaseInlineFormSet, fk_name=None,
                           fields=None, exclude=None,
                           extra=3, can_order=False, can_delete=True, max_num=None,
-                          formfield_callback=lambda f: f.formfield()):
+                          formfield_callback=None):
     """
     Returns an ``InlineFormSet`` for the given kwargs.
 

tests/regressiontests/model_forms_regress/tests.py

@@ -250,3 +250,47 @@ class URLFieldTests(TestCase):
         form.is_valid()
         # self.assertTrue(form.is_valid())
         # self.assertEquals(form.cleaned_data['url'], 'http://example.com/test')
+
+
+class FormFieldCallbackTests(TestCase):
+
+    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}
+
+        Form = modelform_factory(Person, form=BaseForm)
+        self.assertTrue(Form.base_fields['name'].widget is widget)
+
+    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}
+
+        _ = 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
+        self.assertRaises(TypeError, modelform_factory, Person,
+                          formfield_callback='not a function or callable')
+

tests/regressiontests/model_formsets_regress/tests.py

@@ -1,8 +1,10 @@
-from django.forms.models import modelform_factory, inlineformset_factory
+from django import forms
+from django.forms.models import modelform_factory, inlineformset_factory, modelformset_factory
 from django.test import TestCase
 
 from models import User, UserSite, Restaurant, Manager
 
+
 class InlineFormsetTests(TestCase):
     def test_formset_over_to_field(self):
         "A formset over a ForeignKey with a to_field can be saved. Regression for #10243"
@@ -156,3 +158,61 @@ class InlineFormsetTests(TestCase):
         # you can create a formset with an instance of None
         form = Form(instance=None)
         formset = FormSet(instance=None)
+
+
+class CustomWidget(forms.CharField):
+    pass
+
+
+class UserSiteForm(forms.ModelForm):
+    class Meta:
+        model = UserSite
+        widgets = {'data': CustomWidget}
+
+
+class Callback(object):
+
+    def __init__(self):
+        self.log = []
+
+    def __call__(self, db_field, **kwargs):
+        self.log.append((db_field, kwargs))
+        return db_field.formfield(**kwargs)
+
+
+class FormfieldCallbackTests(TestCase):
+    """
+    Regression for #13095: Using base forms with widgets
+    defined in Meta should not raise errors.
+    """
+
+    def test_inlineformset_factory_default(self):
+        Formset = inlineformset_factory(User, UserSite, form=UserSiteForm)
+        form = Formset({}).forms[0]
+        self.assertTrue(isinstance(form['data'].field.widget, CustomWidget))
+
+    def test_modelformset_factory_default(self):
+        Formset = modelformset_factory(UserSite, form=UserSiteForm)
+        form = Formset({}).forms[0]
+        self.assertTrue(isinstance(form['data'].field.widget, CustomWidget))
+
+    def assertCallbackCalled(self, callback):
+        id_field, user_field, data_field = UserSite._meta.fields
+        expected_log = [
+            (id_field, {}),
+            (user_field, {}),
+            (data_field, {'widget': CustomWidget}),
+        ]
+        self.assertEqual(callback.log, expected_log)
+
+    def test_inlineformset_custom_callback(self):
+        callback = Callback()
+        inlineformset_factory(User, UserSite, form=UserSiteForm,
+                              formfield_callback=callback)
+        self.assertCallbackCalled(callback)
+
+    def test_modelformset_custom_callback(self):
+        callback = Callback()
+        modelformset_factory(UserSite, form=UserSiteForm,
+                             formfield_callback=callback)
+        self.assertCallbackCalled(callback)