From 38d9b0919bb07f4dcfcf22a9013b1a711f54ab89 Mon Sep 17 00:00:00 2001
From: Brian Rosner <brosner@gmail.com>
Date: Tue, 28 Oct 2008 20:03:56 +0000
Subject: [PATCH] [0.5.X] Fixed #9462 -- Set the instance in an inline formset
 correctly so that None does not get passed through to the queryset. Thanks
 tobias and copelco for the ticket.

Backport of r9293 from trunk.

git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.0.X@9294 bcc190cf-cafb-0310-a4f2-bffc1f526a37
---
 django/forms/models.py                    |  5 ++++-
 tests/modeltests/model_formsets/models.py | 26 +++++++++++++++++++++++
 2 files changed, 30 insertions(+), 1 deletion(-)

diff --git a/django/forms/models.py b/django/forms/models.py
index 180aec60db..0c98f52660 100644
--- a/django/forms/models.py
+++ b/django/forms/models.py
@@ -446,7 +446,10 @@ class BaseInlineFormSet(BaseModelFormSet):
     def __init__(self, data=None, files=None, instance=None,
                  save_as_new=False, prefix=None):
         from django.db.models.fields.related import RelatedObject
-        self.instance = instance
+        if instance is None:
+            self.instance = self.model()
+        else:
+            self.instance = instance
         self.save_as_new = save_as_new
         # is there a better way to get the object descriptor?
         self.rel_name = RelatedObject(self.fk.rel.to, self.model, self.fk).get_accessor_name()
diff --git a/tests/modeltests/model_formsets/models.py b/tests/modeltests/model_formsets/models.py
index 3c97931595..215f35b59a 100644
--- a/tests/modeltests/model_formsets/models.py
+++ b/tests/modeltests/model_formsets/models.py
@@ -107,6 +107,17 @@ class Membership(models.Model):
     date_joined = models.DateTimeField(default=datetime.datetime.now)
     karma = models.IntegerField()
 
+# models for testing a null=True fk to a parent
+class Team(models.Model):
+    name = models.CharField(max_length=100)
+
+class Player(models.Model):
+    team = models.ForeignKey(Team, null=True)
+    name = models.CharField(max_length=100)
+    
+    def __unicode__(self):
+        return self.name
+
 __test__ = {'API_TESTS': """
 
 >>> from datetime import date
@@ -701,4 +712,19 @@ False
 >>> formset.is_valid()
 True
 
+# inlineformset_factory tests with fk having null=True. see #9462.
+# create some data that will exbit the issue
+>>> team = Team.objects.create(name=u"Red Vipers")
+>>> Player(name="Timmy").save()
+>>> Player(name="Bobby", team=team).save()
+
+>>> PlayerInlineFormSet = inlineformset_factory(Team, Player)
+>>> formset = PlayerInlineFormSet()
+>>> formset.get_queryset()
+[]
+
+>>> formset = PlayerInlineFormSet(instance=team)
+>>> formset.get_queryset()
+[<Player: Bobby>]
+
 """}