[py3] Used six.with_metaclass wherever necessary.

Author: aaugustin

django/contrib/admin/options.py

@@ -24,6 +24,7 @@
 from django.utils.datastructures import SortedDict
 from django.utils.html import escape, escapejs
 from django.utils.safestring import mark_safe
+from django.utils import six
 from django.utils.text import capfirst, get_text_list
 from django.utils.translation import ugettext as _
 from django.utils.translation import ungettext
@@ -57,9 +58,8 @@ class IncorrectLookupParameters(Exception):
 
 csrf_protect_m = method_decorator(csrf_protect)
 
-class BaseModelAdmin(object):
+class BaseModelAdmin(six.with_metaclass(forms.MediaDefiningClass)):
  """Functionality common to both ModelAdmin and InlineAdmin."""
- __metaclass__ = forms.MediaDefiningClass
 
  raw_id_fields = ()
  fields = None

django/db/models/base.py

@@ -24,6 +24,7 @@
 from django.utils.translation import ugettext_lazy as _
 from django.utils.functional import curry
 from django.utils.encoding import smart_str, force_unicode
+from django.utils import six
 from django.utils.text import get_text_list, capfirst
 
 
@@ -275,8 +276,8 @@ def __init__(self, db=None):
  # This impacts validation only; it has no effect on the actual save.
  self.adding = True
 
-class Model(object):
- __metaclass__ = ModelBase
+
+class ModelWithoutMeta(object):
  _deferred = False
 
  def __init__(self, *args, **kwargs):
@@ -369,7 +370,7 @@ def __init__(self, *args, **kwargs):
  pass
  if kwargs:
  raise TypeError("'%s' is an invalid keyword argument for this function" % kwargs.keys()[0])
- super(Model, self).__init__()
+ super(ModelWithoutMeta, self).__init__()
  signals.post_init.send(sender=self.__class__, instance=self)
 
  def __repr__(self):
@@ -401,7 +402,7 @@ def __reduce__(self):
  only module-level classes can be pickled by the default path.
  """
  if not self._deferred:
- return super(Model, self).__reduce__()
+ return super(ModelWithoutMeta, self).__reduce__()
  data = self.__dict__
  defers = []
  for field in self._meta.fields:
@@ -876,6 +877,15 @@ def clean_fields(self, exclude=None):
  raise ValidationError(errors)
 
 
+# For unknown reasons, six.with_metaclass doesn't work correctly for Model.
+# Fallback to exec'ing the appropriate syntax for each Python version.
+
+if six.PY3:
+ six.exec_("class Model(ModelWithoutMeta, metaclass=ModelBase): pass")
+else:
+ six.exec_("class Model(ModelWithoutMeta): __metaclass__ = ModelBase")
+
+
 ############################################
 # HELPER FUNCTIONS (CURRIED MODEL METHODS) #
 ############################################

django/forms/forms.py

@@ -14,6 +14,7 @@
 from django.utils.html import conditional_escape, format_html
 from django.utils.encoding import StrAndUnicode, smart_unicode, force_unicode
 from django.utils.safestring import mark_safe
+from django.utils import six
 
 
 __all__ = ('BaseForm', 'Form')
@@ -380,14 +381,13 @@ def visible_fields(self):
  """
  return [field for field in self if not field.is_hidden]
 
-class Form(BaseForm):
+class Form(six.with_metaclass(DeclarativeFieldsMetaclass, BaseForm)):
  "A collection of Fields, plus their associated data."
  # This is a separate class from BaseForm in order to abstract the way
  # self.fields is specified. This class (Form) is the one that does the
  # fancy metaclass stuff purely for the semantic sugar -- it allows one
  # to define a form using declarative syntax.
  # BaseForm itself has no way of designating self.fields.
- __metaclass__ = DeclarativeFieldsMetaclass
 
 class BoundField(StrAndUnicode):
  "A Field plus data"

django/forms/models.py

@@ -15,6 +15,7 @@
  MultipleHiddenInput, media_property)
 from django.utils.encoding import smart_unicode, force_unicode
 from django.utils.datastructures import SortedDict
+from django.utils import six
 from django.utils.text import get_text_list, capfirst
 from django.utils.translation import ugettext_lazy as _, ugettext
 
@@ -365,8 +366,8 @@ def save(self, commit=True):
 
  save.alters_data = True
 
-class ModelForm(BaseModelForm):
- __metaclass__ = ModelFormMetaclass
+class ModelForm(six.with_metaclass(ModelFormMetaclass, BaseModelForm)):
+ pass
 
 def modelform_factory(model, form=ModelForm, fields=None, exclude=None,
  formfield_callback=None, widgets=None):
@@ -401,6 +402,7 @@ def modelform_factory(model, form=ModelForm, fields=None, exclude=None,
 
  form_metaclass = ModelFormMetaclass
 
+ # TODO: this doesn't work under Python 3.
  if issubclass(form, BaseModelForm) and hasattr(form, '__metaclass__'):
  form_metaclass = form.__metaclass__
 

django/forms/widgets.py

@@ -17,6 +17,7 @@
 from django.utils.encoding import StrAndUnicode, force_unicode
 from django.utils.safestring import mark_safe
 from django.utils import datetime_safe, formats
+from django.utils import six
 
 __all__ = (
  'Media', 'MediaDefiningClass', 'Widget', 'TextInput', 'PasswordInput',
@@ -153,8 +154,7 @@ def __unicode__(self):
  args.append(self.choices)
  return self.parent_widget.render(*args)
 
-class Widget(object):
- __metaclass__ = MediaDefiningClass
+class Widget(six.with_metaclass(MediaDefiningClass)):
  is_hidden = False # Determines whether this corresponds to an <input type="hidden">.
  needs_multipart_form = False # Determines does this widget need multipart form
  is_localized = False