Fixed #26277 -- Added support for null values in ChoicesFieldListFilter.

2 files changed, 23 insertions, 0 deletions

diff --git a/tests/admin_filters/models.py b/tests/admin_filters/models.py
index db37958882..8860201d35 100644
--- a/tests/admin_filters/models.py
+++ b/tests/admin_filters/models.py
@@ -75,5 +75,12 @@ class Bookmark(models.Model):
     url = models.URLField()
     tags = GenericRelation(TaggedItem)
 
+    CHOICES = [
+        ('a', 'A'),
+        (None, 'None'),
+        ('', '-'),
+    ]
+    none_or_null = models.CharField(max_length=20, choices=CHOICES, blank=True, null=True)
+
     def __str__(self):
         return self.url
diff --git a/tests/admin_filters/tests.py b/tests/admin_filters/tests.py
index 3d2f7ab9c6..ba6934f4ed 100644
--- a/tests/admin_filters/tests.py
+++ b/tests/admin_filters/tests.py
@@ -302,6 +302,22 @@ class ListFiltersTests(TestCase):
             modeladmin.list_max_show_all, modeladmin.list_editable, modeladmin,
         )
 
+    def test_choicesfieldlistfilter_has_none_choice(self):
+        """
+        The last choice is for the None value.
+        """
+        class BookmarkChoicesAdmin(ModelAdmin):
+            list_display = ['none_or_null']
+            list_filter = ['none_or_null']
+
+        modeladmin = BookmarkChoicesAdmin(Bookmark, site)
+        request = self.request_factory.get('/', {})
+        changelist = self.get_changelist(request, Bookmark, modeladmin)
+        filterspec = changelist.get_filters(request)[0][0]
+        choices = list(filterspec.choices(changelist))
+        self.assertEqual(choices[-1]['display'], 'None')
+        self.assertEqual(choices[-1]['query_string'], '?none_or_null__isnull=True')
+
     def test_datefieldlistfilter(self):
         modeladmin = BookAdmin(Book, site)