diff -r dc4edca39e41 -r df91e2df6ba3 mercurial/cmdutil.py
--- a/mercurial/cmdutil.py	Thu Oct 03 18:01:21 2013 +0200
+++ b/mercurial/cmdutil.py	Thu Oct 03 18:01:21 2013 +0200
@@ -933,7 +933,7 @@
     regular display via changeset_printer() is done.
     """
     # options
-    patch = False
+    patch = None
     if opts.get('patch') or opts.get('stat'):
         patch = scmutil.matchall(repo)