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, 39 insertions, 20 deletions

diff --git a/docs/topics/forms/formsets.txt b/docs/topics/forms/formsets.txt
index 3fb2b0af16..d65daa5dd5 100644
--- a/docs/topics/forms/formsets.txt
+++ b/docs/topics/forms/formsets.txt
@@ -71,7 +71,7 @@ Limiting the maximum number of forms
 ------------------------------------
 
 The ``max_num`` parameter to ``formset_factory`` gives you the ability to
-force the maximum number of forms the formset will display::
+limit the maximum number of empty forms the formset will display::
 
     >>> ArticleFormSet = formset_factory(ArticleForm, extra=2, max_num=1)
     >>> formset = ArticleFormset()
@@ -80,8 +80,20 @@ force the maximum number of forms the formset will display::
     <tr><th><label for="id_form-0-title">Title:</label></th><td><input type="text" name="form-0-title" id="id_form-0-title" /></td></tr>
     <tr><th><label for="id_form-0-pub_date">Pub date:</label></th><td><input type="text" name="form-0-pub_date" id="id_form-0-pub_date" /></td></tr>
 
-A ``max_num`` value of ``0`` (the default) puts no limit on the number forms
-displayed.
+.. versionchanged:: 1.2
+
+If the value of ``max_num`` is geater than the number of existing related
+objects, up to ``extra`` additional blank forms will be added to the formset,
+so long as the total number of forms does not exceed ``max_num``.
+
+A ``max_num`` value of ``None`` (the default) puts no limit on the number of
+forms displayed. Please note that the default value of ``max_num`` was changed
+from ``0`` to ``None`` in version 1.2 to allow ``0`` as a valid value.
+
+.. versionadded:: 1.2
+
+The dynamic "Add Another" link in the Django admin will not appear if
+``max_num`` is less than the number of currently displayed forms.
 
 Formset validation
 ------------------
@@ -102,7 +114,7 @@ provide an invalid article::
     >>> data = {
     ...     'form-TOTAL_FORMS': u'2',
     ...     'form-INITIAL_FORMS': u'0',
-    ...     'form-MAX_NUM_FORMS': u'0',
+    ...     'form-MAX_NUM_FORMS': u'',
     ...     'form-0-title': u'Test',
     ...     'form-0-pub_date': u'16 June 1904',
     ...     'form-1-title': u'Test',
@@ -190,7 +202,7 @@ is where you define your own validation that works at the formset level::
     >>> data = {
     ...     'form-TOTAL_FORMS': u'2',
     ...     'form-INITIAL_FORMS': u'0',
-    ...     'form-MAX_NUM_FORMS': u'0',
+    ...     'form-MAX_NUM_FORMS': u'',
     ...     'form-0-title': u'Test',
     ...     'form-0-pub_date': u'16 June 1904',
     ...     'form-1-title': u'Test',
@@ -249,7 +261,7 @@ happen when the user changes these values::
     >>> data = {
     ...     'form-TOTAL_FORMS': u'3',
     ...     'form-INITIAL_FORMS': u'2',
-    ...     'form-MAX_NUM_FORMS': u'0',
+    ...     'form-MAX_NUM_FORMS': u'',
     ...     'form-0-title': u'Article #1',
     ...     'form-0-pub_date': u'2008-05-10',
     ...     'form-0-ORDER': u'2',
@@ -287,7 +299,7 @@ Lets create a formset with the ability to delete::
     ... ])
     >>> for form in formset.forms:
     ....    print form.as_table()
-    <input type="hidden" name="form-TOTAL_FORMS" value="3" id="id_form-TOTAL_FORMS" /><input type="hidden" name="form-INITIAL_FORMS" value="2" id="id_form-INITIAL_FORMS" /><input type="hidden" name="form-MAX_NUM_FORMS" value="0" id="id_form-MAX_NUM_FORMS" />
+    <input type="hidden" name="form-TOTAL_FORMS" value="3" id="id_form-TOTAL_FORMS" /><input type="hidden" name="form-INITIAL_FORMS" value="2" id="id_form-INITIAL_FORMS" /><input type="hidden" name="form-MAX_NUM_FORMS" id="id_form-MAX_NUM_FORMS" />
     <tr><th><label for="id_form-0-title">Title:</label></th><td><input type="text" name="form-0-title" value="Article #1" id="id_form-0-title" /></td></tr>
     <tr><th><label for="id_form-0-pub_date">Pub date:</label></th><td><input type="text" name="form-0-pub_date" value="2008-05-10" id="id_form-0-pub_date" /></td></tr>
     <tr><th><label for="id_form-0-DELETE">Delete:</label></th><td><input type="checkbox" name="form-0-DELETE" id="id_form-0-DELETE" /></td></tr>
@@ -305,7 +317,7 @@ delete fields you can access them with ``deleted_forms``::
     >>> data = {
     ...     'form-TOTAL_FORMS': u'3',
     ...     'form-INITIAL_FORMS': u'2',
-    ...     'form-MAX_NUM_FORMS': u'0',
+    ...     'form-MAX_NUM_FORMS': u'',
     ...     'form-0-title': u'Article #1',
     ...     'form-0-pub_date': u'2008-05-10',
     ...     'form-0-DELETE': u'on',
diff --git a/docs/topics/forms/modelforms.txt b/docs/topics/forms/modelforms.txt
index 9a64919534..1e9c9db541 100644
--- a/docs/topics/forms/modelforms.txt
+++ b/docs/topics/forms/modelforms.txt
@@ -369,7 +369,7 @@ Overriding the default field types or widgets
 The default field types, as described in the `Field types`_ table above, are
 sensible defaults. If you have a ``DateField`` in your model, chances are you'd
 want that to be represented as a ``DateField`` in your form. But
-``ModelForm`` gives you the flexibility of changing the form field type and 
+``ModelForm`` gives you the flexibility of changing the form field type and
 widget for a given model field.
 
 To specify a custom widget for a field, use the ``widgets`` attribute of the
@@ -401,7 +401,7 @@ field, you could do the following::
 
     class ArticleForm(ModelForm):
         pub_date = MyDateFormField()
-    
+
         class Meta:
             model = Article
 
@@ -557,7 +557,7 @@ with the ``Author`` model. It works just like a regular formset::
 
     >>> formset = AuthorFormSet()
     >>> print formset
-    <input type="hidden" name="form-TOTAL_FORMS" value="1" id="id_form-TOTAL_FORMS" /><input type="hidden" name="form-INITIAL_FORMS" value="0" id="id_form-INITIAL_FORMS" /><input type="hidden" name="form-MAX_NUM_FORMS" value="0" id="id_form-MAX_NUM_FORMS" />
+    <input type="hidden" name="form-TOTAL_FORMS" value="1" id="id_form-TOTAL_FORMS" /><input type="hidden" name="form-INITIAL_FORMS" value="0" id="id_form-INITIAL_FORMS" /><input type="hidden" name="form-MAX_NUM_FORMS" id="id_form-MAX_NUM_FORMS" />
     <tr><th><label for="id_form-0-name">Name:</label></th><td><input id="id_form-0-name" type="text" name="form-0-name" maxlength="100" /></td></tr>
     <tr><th><label for="id_form-0-title">Title:</label></th><td><select name="form-0-title" id="id_form-0-title">
     <option value="" selected="selected">---------</option>
@@ -653,22 +653,24 @@ are saved properly.
 Limiting the number of editable objects
 ---------------------------------------
 
+.. versionchanged:: 1.2
+
 As with regular formsets, you can use the ``max_num`` parameter to
-``modelformset_factory`` to limit the number of forms displayed. With
-model formsets, this property limits the query to select only the maximum
-number of objects needed::
+``modelformset_factory`` to limit the number of extra forms displayed.
+
+``max_num`` does not prevent existing objects from being displayed::
 
     >>> Author.objects.order_by('name')
     [<Author: Charles Baudelaire>, <Author: Paul Verlaine>, <Author: Walt Whitman>]
 
-    >>> AuthorFormSet = modelformset_factory(Author, max_num=2, extra=1)
+    >>> AuthorFormSet = modelformset_factory(Author, max_num=1)
     >>> formset = AuthorFormSet(queryset=Author.objects.order_by('name'))
-    >>> formset.initial
-    [{'id': 1, 'name': u'Charles Baudelaire'}, {'id': 3, 'name': u'Paul Verlaine'}]
+    >>> [x.name for x in formset.get_queryset()]
+    [u'Charles Baudelaire', u'Paul Verlaine', u'Walt Whitman']
 
-If the value of ``max_num`` is higher than the number of objects returned, up to
-``extra`` additional blank forms will be added to the formset, so long as the
-total number of forms does not exceed ``max_num``::
+If the value of ``max_num`` is geater than the number of existing related
+objects, up to ``extra`` additional blank forms will be added to the formset,
+so long as the total number of forms does not exceed ``max_num``::
 
     >>> AuthorFormSet = modelformset_factory(Author, max_num=4, extra=2)
     >>> formset = AuthorFormSet(queryset=Author.objects.order_by('name'))
@@ -679,6 +681,11 @@ total number of forms does not exceed ``max_num``::
     <tr><th><label for="id_form-2-name">Name:</label></th><td><input id="id_form-2-name" type="text" name="form-2-name" value="Walt Whitman" maxlength="100" /><input type="hidden" name="form-2-id" value="2" id="id_form-2-id" /></td></tr>
     <tr><th><label for="id_form-3-name">Name:</label></th><td><input id="id_form-3-name" type="text" name="form-3-name" maxlength="100" /><input type="hidden" name="form-3-id" id="id_form-3-id" /></td></tr>
 
+.. versionchanged:: 1.2
+
+A ``max_num`` value of ``None`` (the default) puts no limit on the number of
+forms displayed.
+
 Using a model formset in a view
 -------------------------------