FormMixin instantiates form with dict stored on the class

[Aron Grififs]

Consider the following form:

class MyForm(ModelForm):
  def __init__(self, *args, **kwargs):
    kwargs['initial']['foo'] = 'bar'
    super(MyForm, self).__init__(*args, **kwargs)

When used with Django's class-based generic views, this will cause all following form instantiations to have a default initial dict with the content {'foo': 'bar'} because the dict is inadvertently updated on the class.

The problem is the following code in [source:django/trunk/django/views/generic/edit.py generic/edit.py]:

class FormMixin(object):
    initial = {}

    def get_initial(self):
        return self.initial

    def get_form_kwargs(self):
        kwargs = {'initial': self.get_initial()}
        ...

I think the right fix here is to shallow-copy the dict in get_initial, will attach patch.

[Claude Paroz]

With test

[alex.vidal@…]

Will this ticket be closed before the release of 1.4? We currently have a monkeypatch in place to deal with the problem, but I'd like to remove it when 1.4 is official.

[Claude Paroz]

This is in fact a duplicate of #16138. Thanks aaugustin for the notice.