--- a/mercurial/scmutil.py	Thu Sep 24 01:58:33 2015 -0700
+++ b/mercurial/scmutil.py	Thu Sep 24 00:59:26 2015 -0700
@@ -753,7 +753,7 @@
         ret.append(kindpat)
     return ret
 
-def matchandpats(ctx, pats=[], opts={}, globbed=False, default='relpath',
+def matchandpats(ctx, pats=(), opts={}, globbed=False, default='relpath',
                  badfn=None):
     '''Return a matcher and the patterns that were used.
     The matcher will warn about bad matches, unless an alternate badfn callback