Fixed #19044 -- Made `DeletionMixin` interpolate its `success_url`.

Thanks to nxvl and slurms for the initial patch, ptone for the review
and timo for the documentation tweaks.

django/views/generic/edit.py

@@ -242,8 +242,9 @@ class DeletionMixin(object):
         redirects to the success URL.
         """
         self.object = self.get_object()
+        success_url = self.get_success_url()
         self.object.delete()
-        return HttpResponseRedirect(self.get_success_url())
+        return HttpResponseRedirect(success_url)
 
     # Add support for browsers which only accept GET and POST for now.
     def post(self, *args, **kwargs):
@@ -251,7 +252,7 @@ class DeletionMixin(object):
 
     def get_success_url(self):
         if self.success_url:
-            return self.success_url
+            return self.success_url % self.object.__dict__
         else:
             raise ImproperlyConfigured(
                 "No URL to redirect to. Provide a success_url.")

docs/ref/class-based-views/mixins-editing.txt

@@ -201,6 +201,13 @@ ProcessFormView
         The url to redirect to when the nominated object has been
         successfully deleted.
 
+        .. versionadded:: 1.6
+
+        ``success_url`` may contain dictionary string formatting, which
+        will be interpolated against the object's field attributes. For
+        example, you could use ``success_url="/parent/%(parent_id)s/"`` to
+        redirect to a URL composed out of the ``parent_id`` field on a model.
+
     .. method:: get_success_url(obj)
 
         Returns the url to redirect to when the nominated object has been

docs/releases/1.6.txt

@@ -64,6 +64,10 @@ Minor features
   :attr:`~django.core.management.BaseCommand.leave_locale_alone` internal
   option. See :ref:`management-commands-and-locales` for more details.
 
+* The :attr:`~django.views.generic.edit.DeletionMixin.success_url` of
+  :class:`~django.views.generic.edit.DeletionMixin` is now interpolated with
+  its ``object``\'s ``__dict__``.
+
 Backwards incompatible changes in 1.6
 =====================================
 

tests/regressiontests/generic_views/edit.py

@@ -13,12 +13,12 @@ from .models import Artist, Author
 
 
 class FormMixinTests(TestCase):
-     def test_initial_data(self):
-         """ Test instance independence of initial data dict (see #16138) """
-         initial_1 = FormMixin().get_initial()
-         initial_1['foo'] = 'bar'
-         initial_2 = FormMixin().get_initial()
-         self.assertNotEqual(initial_1, initial_2)
+    def test_initial_data(self):
+        """ Test instance independence of initial data dict (see #16138) """
+        initial_1 = FormMixin().get_initial()
+        initial_1['foo'] = 'bar'
+        initial_2 = FormMixin().get_initial()
+        self.assertNotEqual(initial_1, initial_2)
 
 
 class BasicFormTests(TestCase):
@@ -283,6 +283,13 @@ class DeleteViewTests(TestCase):
         self.assertRedirects(res, 'http://testserver/edit/authors/create/')
         self.assertQuerysetEqual(Author.objects.all(), [])
 
+    def test_delete_with_interpolated_redirect(self):
+        a = Author.objects.create(**{'name': 'Randall Munroe', 'slug': 'randall-munroe'})
+        res = self.client.post('/edit/author/%d/delete/interpolate_redirect/' % a.pk)
+        self.assertEqual(res.status_code, 302)
+        self.assertRedirects(res, 'http://testserver/edit/authors/create/?deleted=%d' % a.pk)
+        self.assertQuerysetEqual(Author.objects.all(), [])
+
     def test_delete_with_special_properties(self):
         a = Author.objects.create(**{'name': 'Randall Munroe', 'slug': 'randall-munroe'})
         res = self.client.get('/edit/author/%d/delete/special/' % a.pk)

tests/regressiontests/generic_views/urls.py

@@ -97,6 +97,8 @@ urlpatterns = patterns('',
         views.NaiveAuthorDelete.as_view()),
     (r'^edit/author/(?P<pk>\d+)/delete/redirect/$',
         views.NaiveAuthorDelete.as_view(success_url='/edit/authors/create/')),
+    (r'^edit/author/(?P<pk>\d+)/delete/interpolate_redirect/$',
+        views.NaiveAuthorDelete.as_view(success_url='/edit/authors/create/?deleted=%(id)s')),
     (r'^edit/author/(?P<pk>\d+)/delete/$',
         views.AuthorDelete.as_view()),
     (r'^edit/author/(?P<pk>\d+)/delete/special/$',