Fixed #14877 -- repeated deletion using formsets

When a formset contained deletion for an existing instance, and the
instance was already deleted, django threw an exception. A common cause for
this was resubmit of the formset.

Original patch by Trac alias olau.

In addition this commit cleaned some code in _construct_form(). This
was needed as the primary key value the user submitted wasn't converted
correctly to python value in case the primary key field was also a
related field.

1 files changed, 49 insertions, 0 deletions

diff --git a/tests/model_formsets_regress/tests.py b/tests/model_formsets_regress/tests.py
index a79d3744e0..f8a5b7b3ac 100644
--- a/tests/model_formsets_regress/tests.py
+++ b/tests/model_formsets_regress/tests.py
@@ -454,3 +454,52 @@ class FormfieldShouldDeleteFormTests(TestCase):
         # verify no "odd" PKs left
         odd_ids = [user.pk for user in User.objects.all() if user.pk % 2]
         self.assertEqual(len(odd_ids), 0)
+
+
+class RedeleteTests(TestCase):
+    def test_resubmit(self):
+        u = User.objects.create(username='foo', serial=1)
+        us = UserSite.objects.create(user=u, data=7)
+        formset_cls = inlineformset_factory(User, UserSite, fields="__all__")
+        data = {
+            'serial': '1',
+            'username': 'foo',
+            'usersite_set-TOTAL_FORMS': '1',
+            'usersite_set-INITIAL_FORMS': '1',
+            'usersite_set-MAX_NUM_FORMS': '1',
+            'usersite_set-0-id': six.text_type(us.pk),
+            'usersite_set-0-data': '7',
+            'usersite_set-0-user': 'foo',
+            'usersite_set-0-DELETE': '1'
+        }
+        formset = formset_cls(data, instance=u)
+        self.assertTrue(formset.is_valid())
+        formset.save()
+        self.assertEqual(UserSite.objects.count(), 0)
+        formset = formset_cls(data, instance=u)
+        # Even if the "us" object isn't in the DB any more, the form
+        # validates.
+        self.assertTrue(formset.is_valid())
+        formset.save()
+        self.assertEqual(UserSite.objects.count(), 0)
+
+    def test_delete_already_deleted(self):
+        u = User.objects.create(username='foo', serial=1)
+        us = UserSite.objects.create(user=u, data=7)
+        formset_cls = inlineformset_factory(User, UserSite, fields="__all__")
+        data = {
+            'serial': '1',
+            'username': 'foo',
+            'usersite_set-TOTAL_FORMS': '1',
+            'usersite_set-INITIAL_FORMS': '1',
+            'usersite_set-MAX_NUM_FORMS': '1',
+            'usersite_set-0-id': six.text_type(us.pk),
+            'usersite_set-0-data': '7',
+            'usersite_set-0-user': 'foo',
+            'usersite_set-0-DELETE': '1'
+        }
+        formset = formset_cls(data, instance=u)
+        us.delete()
+        self.assertTrue(formset.is_valid())
+        formset.save()
+        self.assertEqual(UserSite.objects.count(), 0)