diff -r 369ddc9c0339 -r 7239e06e58e9 mercurial/context.py
--- a/mercurial/context.py	Wed Jun 25 17:33:34 2008 -0500
+++ b/mercurial/context.py	Wed Jun 25 17:33:51 2008 -0500
@@ -19,11 +19,8 @@
         if not changeid and changeid != 0:
             p1, p2 = self._repo.dirstate.parents()
             self._rev = self._repo.changelog.rev(p1)
-            if self._rev == -1:
-                changeid = 'tip'
-            else:
-                self._node = p1
-                return
+            self._node = p1
+            return
 
         self._node = self._repo.lookup(changeid)
         self._rev = self._repo.changelog.rev(self._node)