Fixed #13023 - Removed ambiguity with regard to the max_num option of formsets and as a result of admin inlines. Thanks to Gabriel Hurley for the patch.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@12872 bcc190cf-cafb-0310-a4f2-bffc1f526a37

2 files changed, 16 insertions, 11 deletions

diff --git a/django/forms/formsets.py b/django/forms/formsets.py
index ec14f813e9..3804f2b3c1 100644
--- a/django/forms/formsets.py
+++ b/django/forms/formsets.py
@@ -25,7 +25,7 @@ class ManagementForm(Form):
     def __init__(self, *args, **kwargs):
         self.base_fields[TOTAL_FORM_COUNT] = IntegerField(widget=HiddenInput)
         self.base_fields[INITIAL_FORM_COUNT] = IntegerField(widget=HiddenInput)
-        self.base_fields[MAX_NUM_FORM_COUNT] = IntegerField(widget=HiddenInput)
+        self.base_fields[MAX_NUM_FORM_COUNT] = IntegerField(required=False, widget=HiddenInput)
         super(ManagementForm, self).__init__(*args, **kwargs)
 
 class BaseFormSet(StrAndUnicode):
@@ -69,8 +69,13 @@ class BaseFormSet(StrAndUnicode):
         if self.data or self.files:
             return self.management_form.cleaned_data[TOTAL_FORM_COUNT]
         else:
-            total_forms = self.initial_form_count() + self.extra
-            if total_forms > self.max_num > 0:
+            initial_forms = self.initial_form_count()
+            total_forms = initial_forms + self.extra
+            # Allow all existing related objects/inlines to be displayed,
+            # but don't allow extra beyond max_num.
+            if initial_forms > self.max_num >= 0:
+                total_forms = initial_forms
+            elif total_forms > self.max_num >= 0:
                 total_forms = self.max_num
         return total_forms
 
@@ -81,7 +86,7 @@ class BaseFormSet(StrAndUnicode):
         else:
             # Use the length of the inital data if it's there, 0 otherwise.
             initial_forms = self.initial and len(self.initial) or 0
-            if initial_forms > self.max_num > 0:
+            if initial_forms > self.max_num >= 0:
                 initial_forms = self.max_num
         return initial_forms
 
@@ -324,7 +329,7 @@ class BaseFormSet(StrAndUnicode):
         return mark_safe(u'\n'.join([unicode(self.management_form), forms]))
 
 def formset_factory(form, formset=BaseFormSet, extra=1, can_order=False,
-                    can_delete=False, max_num=0):
+                    can_delete=False, max_num=None):
     """Return a FormSet for the given form class."""
     attrs = {'form': form, 'extra': extra,
              'can_order': can_order, 'can_delete': can_delete,
diff --git a/django/forms/models.py b/django/forms/models.py
index 869138c922..608b87bd33 100644
--- a/django/forms/models.py
+++ b/django/forms/models.py
@@ -448,10 +448,10 @@ class BaseModelFormSet(BaseFormSet):
             if not qs.ordered:
                 qs = qs.order_by(self.model._meta.pk.name)
 
-            if self.max_num > 0:
-                self._queryset = qs[:self.max_num]
-            else:
-                self._queryset = qs
+            # Removed queryset limiting here. As per discussion re: #13023
+            # on django-dev, max_num should not prevent existing
+            # related objects/inlines from being displayed.
+            self._queryset = qs
         return self._queryset
 
     def save_new(self, form, commit=True):
@@ -649,7 +649,7 @@ class BaseModelFormSet(BaseFormSet):
 def modelformset_factory(model, form=ModelForm, formfield_callback=lambda f: f.formfield(),
                          formset=BaseModelFormSet,
                          extra=1, can_delete=False, can_order=False,
-                         max_num=0, fields=None, exclude=None):
+                         max_num=None, fields=None, exclude=None):
     """
     Returns a FormSet class for the given Django model class.
     """
@@ -799,7 +799,7 @@ def _get_foreign_key(parent_model, model, fk_name=None, can_fail=False):
 def inlineformset_factory(parent_model, model, form=ModelForm,
                           formset=BaseInlineFormSet, fk_name=None,
                           fields=None, exclude=None,
-                          extra=3, can_order=False, can_delete=True, max_num=0,
+                          extra=3, can_order=False, can_delete=True, max_num=None,
                           formfield_callback=lambda f: f.formfield()):
     """
     Returns an ``InlineFormSet`` for the given kwargs.