--- a/tests/test-evolve-obshistory.t	Fri Apr 27 16:14:10 2018 +0800
+++ b/tests/test-evolve-obshistory.t	Fri Apr 27 16:19:45 2018 +0800
@@ -16,6 +16,20 @@
   > evolution.effect-flags = yes
   > EOF
 
+Test simple common cases
+========================
+
+Test setup
+----------
+  $ hg init $TESTTMP/simple
+  $ cd $TESTTMP/simple
+
+Actual test
+-----------
+  $ hg obslog -ap null
+  @  000000000000 (-1)
+  
+
 Test output on amended commit
 =============================