Fixed #17642 -- Added min_num support to modelformsets, inlines, and the admin.

Thanks Stephen Burrows for work on the patch as well.

Forwardport of 2914f66983a92fcae55673c517dd8d01e8c238c4 from stable/1.7.x

4 files changed, 29 insertions, 4 deletions

diff --git a/docs/ref/checks.txt b/docs/ref/checks.txt
index 67dc335d80..c8e97df660 100644
--- a/docs/ref/checks.txt
+++ b/docs/ref/checks.txt
@@ -205,7 +205,8 @@ inline on a :class:`~django.contrib.admin.ModelAdmin`.
 * **admin.E202**: ``<model>`` has no ForeignKey to ``<parent model>``./``<model>`` has more than one ForeignKey to ``<parent model>``.
 * **admin.E203**: The value of ``extra`` must be an integer.
 * **admin.E204**: The value of ``max_num`` must be an integer.
-* **admin.E205**: The value of ``formset`` must inherit from ``BaseModelFormSet``.
+* **admin.E205**: The value of ``min_num`` must be an integer.
+* **admin.E206**: The value of ``formset`` must inherit from ``BaseModelFormSet``.
 
 GenericInlineModelAdmin
 ~~~~~~~~~~~~~~~~~~~~~~~
diff --git a/docs/ref/contrib/admin/index.txt b/docs/ref/contrib/admin/index.txt
index 1a02d3fc3b..876bf290c3 100644
--- a/docs/ref/contrib/admin/index.txt
+++ b/docs/ref/contrib/admin/index.txt
@@ -1966,6 +1966,16 @@ The ``InlineModelAdmin`` class adds:
     :meth:`InlineModelAdmin.get_max_num` also allows you to customize the
     maximum number of extra forms.
 
+.. attribute:: InlineModelAdmin.min_num
+
+    .. versionadded:: 1.7
+
+    This controls the minimum number of forms to show in the inline.
+    See :func:`~django.forms.models.modelformset_factory` for more information.
+
+    :meth:`InlineModelAdmin.get_min_num` also allows you to customize the
+    minimum number of displayed forms.
+
 .. attribute:: InlineModelAdmin.raw_id_fields
 
     By default, Django's admin uses a select-box interface (<select>) for
@@ -2042,6 +2052,16 @@ The ``InlineModelAdmin`` class adds:
                     return max_num - 5
                 return max_num
 
+.. method:: InlineModelAdmin.get_min_num(request, obj=None, **kwargs)
+
+    .. versionadded:: 1.7
+
+    Returns the minimum number of inline forms to use. By default,
+    returns the :attr:`InlineModelAdmin.min_num` attribute.
+
+    Override this method to programmatically determine the minimum number of
+    inline forms. For example, this may be based on the model instance
+    (passed as the keyword argument ``obj``).
 
 Working with a model with two or more foreign keys to the same parent model
 ---------------------------------------------------------------------------
diff --git a/docs/ref/contrib/contenttypes.txt b/docs/ref/contrib/contenttypes.txt
index ccb9ccaa8e..eb93d2287f 100644
--- a/docs/ref/contrib/contenttypes.txt
+++ b/docs/ref/contrib/contenttypes.txt
@@ -495,7 +495,7 @@ The :mod:`django.contrib.contenttypes.forms` module provides:
 
         This class used to be defined in ``django.contrib.contenttypes.generic``.
 
-.. function:: generic_inlineformset_factory(model, form=ModelForm, formset=BaseGenericInlineFormSet, ct_field="content_type", fk_field="object_id", fields=None, exclude=None, extra=3, can_order=False, can_delete=True, max_num=None, formfield_callback=None, validate_max=False, for_concrete_model=True)
+.. function:: generic_inlineformset_factory(model, form=ModelForm, formset=BaseGenericInlineFormSet, ct_field="content_type", fk_field="object_id", fields=None, exclude=None, extra=3, can_order=False, can_delete=True, max_num=None, formfield_callback=None, validate_max=False, for_concrete_model=True, min_num=None, validate_min=False)
 
     Returns a ``GenericInlineFormSet`` using
     :func:`~django.forms.models.modelformset_factory`.
@@ -514,6 +514,10 @@ The :mod:`django.contrib.contenttypes.forms` module provides:
 
         This function used to be defined in ``django.contrib.contenttypes.generic``.
 
+    .. versionchanged:: 1.7
+
+        ``min_num`` and ``validate_min`` were added.
+
 
 .. module:: django.contrib.contenttypes.admin
 
diff --git a/docs/ref/forms/models.txt b/docs/ref/forms/models.txt
index f9bf847068..99ff9911f1 100644
--- a/docs/ref/forms/models.txt
+++ b/docs/ref/forms/models.txt
@@ -45,7 +45,7 @@ Model Form Functions
         Previously, omitting the list of fields was allowed and resulted in
         a form with all fields of the model.
 
-.. function:: modelformset_factory(model, form=ModelForm, formfield_callback=None, formset=BaseModelFormSet, extra=1, can_delete=False, can_order=False, max_num=None, fields=None, exclude=None, widgets=None, validate_max=False, localized_fields=None, labels=None, help_texts=None, error_messages=None)
+.. function:: modelformset_factory(model, form=ModelForm, formfield_callback=None, formset=BaseModelFormSet, extra=1, can_delete=False, can_order=False, max_num=None, fields=None, exclude=None, widgets=None, validate_max=False, localized_fields=None, labels=None, help_texts=None, error_messages=None, min_num=None, validate_min=False)
 
     Returns a ``FormSet`` class for the given ``model`` class.
 
@@ -61,7 +61,7 @@ Model Form Functions
 
     See :ref:`model-formsets` for example usage.
 
-.. function:: 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=None, formfield_callback=None, widgets=None, validate_max=False, localized_fields=None, labels=None, help_texts=None, error_messages=None)
+.. function:: 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=None, formfield_callback=None, widgets=None, validate_max=False, localized_fields=None, labels=None, help_texts=None, error_messages=None, min_num=None, validate_min=False)
 
     Returns an ``InlineFormSet`` using :func:`modelformset_factory` with
     defaults of ``formset=``:class:`~django.forms.models.BaseInlineFormSet`,