--- a/tests/test-topic.t	Fri Jan 25 16:51:36 2019 +0530
+++ b/tests/test-topic.t	Sun Jan 27 17:39:09 2019 +0800
@@ -860,6 +860,10 @@
   3: featureA
   $ tlog 'featureA#topic[0]'
   3: featureA
+  $ tlog 'featureA#topic[:]'
+  1: featureA
+  2: featureA
+  3: featureA
 
   $ tlog '2#t[-2]'
   $ tlog '2#t[-1]'
@@ -869,6 +873,10 @@
   $ tlog '2#t[1]'
   3: featureA
   $ tlog '2#t[2]'
+  $ tlog '2#t[-1:1]'
+  1: featureA
+  2: featureA
+  3: featureA
 
 stack subscript relation