Do not check ManyToMany field in a model field

Such checks must be done in a ModelForm clean() method as ManyToMany
field cannot be manipulated on an as-yet-to-be-saved object.

docbow_project/docbow/admin.py

@@ -111,6 +111,7 @@ class ContentAdmin(admin.ModelAdmin):
 class AutomaticForwardingAdmin(admin.ModelAdmin):
     filter_horizontal = [ 'filetypes', 'originaly_to_user', 'forward_to_user',
             'forward_to_list' ]
+    form = forms.AutomaticForwardingForm
 
 
 

docbow_project/docbow/forms.py

@@ -7,8 +7,10 @@ from django import forms
 from django.contrib.auth.models import User
 from django.utils.translation import ugettext as _
 from django.contrib.admin.widgets import FilteredSelectMultiple as AdminFilteredSelectMultiple
+from django.forms import ValidationError
 
-from models import Document, username, MailingList, FileType, Content, AttachedFile
+from models import Document, username, MailingList, FileType, Content, \
+    AttachedFile, AutomaticForwarding
 from uni_form.helpers import FormHelper, Submit, Layout, ButtonHolder
 import pyuca
 from widgets import TextInpuWithPredefinedValues, JqueryFileUploadInput
@@ -179,3 +181,14 @@ class DelegationForm(Form):
     first_name = CharField(label=_('Firstname'))
     last_name = CharField(label=_('Lastname'))
     email = EmailField(label=_('Email'))
+
+class AutomaticForwardingForm(ModelForm):
+    class Meta:
+        model = AutomaticForwarding
+
+    def clean(self):
+        cleaned_data = super(AutomaticForwardingForm, self).clean()
+        if not cleaned_data.get('forward_to_user') and not cleaned_data.get('forward_to_list'):
+            raise ValidationError(_('A forwarding rule must have at least one recipient, person or list.'))
+        return cleaned_data
+

docbow_project/docbow/models.py

@@ -194,10 +194,6 @@ class AutomaticForwarding(Model):
                     + list(self.forward_to_list.all())) }
         return _('Forward documents of type %(filetypes)s automatically to %(to)s') % ctx
 
-    def clean(self):
-        if not self.forward_to_user.count() and not self.forward_to_list.count():
-            raise ValidationError(_('A forwarding rule must have at least one recipient, person or list.'))
-
     class Meta:
         verbose_name = _('Automatic forwarding rule')
         verbose_name_plural = _('Automatic forwarding rules')

docbow_project/locale/fr/LC_MESSAGES/django.po

@@ -222,7 +222,7 @@ msgstr "Transfert les documents du type %(filetypes)s automatiquement à %(to)s"
 #: docbow/models.py:197
 msgid "A forwarding rule must have at least one recipient, person or list."
 msgstr ""
-"Un destinataire d'origine, au moins, doit correspondre pour que la règle s'applique."
+"Une règle de transfert doit contenir au moins un nouveau destinataire; une personne ou une liste."
 
 #: docbow/models.py:200
 msgid "Automatic forwarding rule"