--- a/tests/test-revset.t	Sun May 24 10:29:33 2015 +0900
+++ b/tests/test-revset.t	Sat May 23 11:14:00 2015 +0900
@@ -1602,6 +1602,14 @@
   $ echo default5 >> a
   $ hg ci -m5
 
+"null" revision belongs to "default" branch (issue4683)
+
+  $ log 'branch(null)'
+  0
+  1
+  4
+  5
+
 "null" revision belongs to "default" branch, but it shouldn't appear in set
 unless explicitly specified (issue4682)