From bba6c5042a9724cbe9a158f240d01c00564308bb Mon Sep 17 00:00:00 2001
From: Mads Kiilerich <madski@unity3d.com>
Date: Tue, 29 Jan 2013 17:01:41 +0100
Subject: [PATCH] OS X: try cheap ascii .lower() in normcase before making full
 unicode dance

This is similar to what is done in encoding.lower, introduced in e7a5733d533f.

This has been seen making 'hg up' and 'hg st' in a 50000+ files repo 13%
faster.

This might make Mercurial slightly slower for users who mainly use non-ASCII
filenames. That is a reasonable trade-off.
---
 mercurial/posix.py | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/mercurial/posix.py b/mercurial/posix.py
index 3782be4dde..bbb2a2affa 100644
--- a/mercurial/posix.py
+++ b/mercurial/posix.py
@@ -194,6 +194,11 @@ if sys.platform == 'darwin':
     import fcntl # only needed on darwin, missing on jython
 
     def normcase(path):
+        try:
+            path.decode('ascii') # throw exception for non-ASCII character
+            return path.lower()
+        except UnicodeDecodeError:
+            pass
         try:
             u = path.decode('utf-8')
         except UnicodeDecodeError: