diff --git a/mercurial/dirstate.py b/mercurial/dirstate.py
--- a/mercurial/dirstate.py
+++ b/mercurial/dirstate.py
@@ -73,9 +73,10 @@ class dirstate(object):
     def _pl(self):
         try:
             st = self._opener("dirstate").read(40)
-            if len(st) == 40:
+            l = len(st)
+            if l == 40:
                 return st[:20], st[20:40]
-            if len(st) < 40:
+            elif l > 0 and l < 40:
                 raise util.Abort(_('working directory state appears damaged!'))
         except IOError, err:
             if err.errno != errno.ENOENT: raise