Fixed #10082 -- Modified BaseFormSet so that ordering checks work when the formset is empty. Thanks to Petr Marhoun for the report and test case, and bmathieu for the fix.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@10643 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/forms/formsets.py

@@ -170,18 +170,18 @@ class BaseFormSet(StrAndUnicode):
                 # don't add data marked for deletion to self.ordered_data
                 if self.can_delete and form.cleaned_data[DELETION_FIELD_NAME]:
                     continue
-                # A sort function to order things numerically ascending, but
-                # None should be sorted below anything else. Allowing None as
-                # a comparison value makes it so we can leave ordering fields
-                # blamk.
-                def compare_ordering_values(x, y):
-                    if x[1] is None:
-                        return 1
-                    if y[1] is None:
-                        return -1
-                    return x[1] - y[1]
                 self._ordering.append((i, form.cleaned_data[ORDERING_FIELD_NAME]))
             # After we're done populating self._ordering, sort it.
+            # A sort function to order things numerically ascending, but
+            # None should be sorted below anything else. Allowing None as
+            # a comparison value makes it so we can leave ordering fields
+            # blamk.
+            def compare_ordering_values(x, y):
+                if x[1] is None:
+                    return 1
+                if y[1] is None:
+                    return -1
+                return x[1] - y[1]
             self._ordering.sort(compare_ordering_values)
         # Return a list of form.cleaned_data dicts in the order spcified by
         # the form data.

tests/regressiontests/forms/formsets.py

@@ -394,6 +394,18 @@ True
 {'votes': 500, 'ORDER': None, 'choice': u'The Decemberists'}
 {'votes': 50, 'ORDER': None, 'choice': u'Basia Bulat'}
 
+Ordering should work with blank fieldsets.
+
+>>> data = {
+...     'choices-TOTAL_FORMS': '3', # the number of forms rendered
+...     'choices-INITIAL_FORMS': '0', # the number of forms with initial data
+... }
+
+>>> formset = ChoiceFormSet(data, auto_id=False, prefix='choices')
+>>> formset.is_valid()
+True
+>>> for form in formset.ordered_forms:
+...    print form.cleaned_data
 
 # FormSets with ordering + deletion ###########################################