id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
17137	ModelForm is_valid() accepts options outside choices	hayrynen@…	nobody	"If form is made using ModelForm and choices of ManyToMany field are limited like this:

-- snip
models.py:

class Product(models.Model):
   name = models.CharField(max_length=60, verbose_name=""Name"")
   visibility = models.ManyToManyField(Group, verbose_name=""Groups"")


views.py:

class ProductForm(forms.ModelForm):
   def __init__(self, group_choices, *args, **kwargs):
       super(ProductForm, self).__init__(*args, **kwargs)
       self.fields['visibility'].choices = group_choices
   class Meta:
       model = Product

@login_required
def products_view(request):
   userprofile = UserProfile.objects.get(user = request.user)
   groups = [ (i.id, i.group) for i in Membership.objects.filter(userprofile=userprofile) ]

   if request.method == ""POST"":
       form = ProductForm(groups, request.POST)
       if form.is_valid():
           .. do stuff with visibility trusting form.is_valid()
-- snip

is_valid() allows values for ManyToMany selections outside what is specified in the form as long as there exists corresponding ID in the database. Obviously the submitted form needs to be modified outside standard browser UI.

is_valid() should compare selections against .choices, not against what exists in the database.

"	Bug	new	Forms	1.3	Normal				Unreviewed	0	0	0	0	0	0