diff -r 5a96df266b2b -r 8110405cf8ae mercurial/scmutil.py
--- a/mercurial/scmutil.py	Tue Oct 07 00:18:08 2014 -0700
+++ b/mercurial/scmutil.py	Mon Oct 06 11:43:32 2014 -0700
@@ -478,7 +478,7 @@
         return repo[default]
 
     l = revrange(repo, [revspec])
-    if len(l) < 1:
+    if not l:
         raise util.Abort(_('empty revision set'))
     return repo[l[-1]]