Corrected the behavior of the SimpleFilter.lookups method to also be able to return None. Also modified example in documentation to be a bite more realistic. Refs #5833. Thanks for the hint, Martin Mahner.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@16150 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/contrib/admin/filters.py

@@ -63,7 +63,10 @@ class SimpleListFilter(ListFilter):
             raise ImproperlyConfigured(
                 "The list filter '%s' does not specify "
                 "a 'parameter_name'." % self.__class__.__name__)
-        self.lookup_choices = self.lookups(request)
+        lookup_choices = self.lookups(request)
+        if lookup_choices is None:
+            lookup_choices = ()
+        self.lookup_choices = lookup_choices
 
     def has_output(self):
         return len(self.lookup_choices) > 0

docs/ref/contrib/admin/index.txt

@@ -607,15 +607,12 @@ subclass::
                   class AuthDecadeBornListFilter(DecadeBornListFilter):
 
                       def lookups(self, request):
-                          if request.user.is_authenticated():
-                              return (
-                                  ('80s', 'in the eighties'),
-                                  ('other', 'other'),
-                              )
-                          else:
-                              return (
-                                  ('90s', 'in the nineties'),
-                              )
+                          if request.user.is_superuser:
+                              return super(AuthDecadeBornListFilter, self).lookups(request)
+
+                      def queryset(self, request, queryset):
+                          if request.user.is_superuser:
+                              return super(AuthDecadeBornListFilter, self).queryset(request, queryset)
 
         * a tuple, where the first element is a field name and the second
           element is a class inheriting from

tests/regressiontests/admin_filters/tests.py

@@ -43,6 +43,11 @@ class DecadeListFilterWithoutTitle(DecadeListFilter):
 class DecadeListFilterWithoutParameter(DecadeListFilter):
     title = 'publication decade'
 
+class DecadeListFilterWithNoneReturningLookups(DecadeListFilterWithTitleAndParameter):
+
+    def lookups(self, request):
+        pass
+
 class CustomUserAdmin(UserAdmin):
     list_filter = ('books_authored', 'books_contributed')
 
@@ -60,6 +65,9 @@ class DecadeFilterBookAdminWithoutTitle(ModelAdmin):
 class DecadeFilterBookAdminWithoutParameter(ModelAdmin):
     list_filter = (DecadeListFilterWithoutParameter,)
 
+class DecadeFilterBookAdminWithNoneReturningLookups(ModelAdmin):
+    list_filter = (DecadeListFilterWithNoneReturningLookups,)
+
 class ListFiltersTests(TestCase):
 
     def setUp(self):
@@ -453,3 +461,14 @@ class ListFiltersTests(TestCase):
         self.assertRaisesRegexp(ImproperlyConfigured,
             "The list filter 'DecadeListFilterWithoutParameter' does not specify a 'parameter_name'.",
             self.get_changelist, request, Book, modeladmin)
+
+    def test_simplelistfilter_with_none_returning_lookups(self):
+        """
+        A SimpleListFilter lookups method can return None but disables the
+        filter completely.
+        """
+        modeladmin = DecadeFilterBookAdminWithNoneReturningLookups(Book, site)
+        request = self.request_factory.get('/', {})
+        changelist = self.get_changelist(request, Book, modeladmin)
+        filterspec = changelist.get_filters(request)[0]
+        self.assertEqual(len(filterspec), 0)