hgext/releasenotes.py

--- a/hgext/releasenotes.py	Thu Aug 03 15:31:54 2017 +0200
+++ b/hgext/releasenotes.py	Sat Aug 12 09:21:42 2017 +0530
@@ -426,7 +426,7 @@
 
             lines.append('')
 
-    if lines[-1]:
+    if lines and lines[-1]:
         lines.append('')
 
     return '\n'.join(lines)