using unicode strings for locale.normalize gives following traceback with python2.7:

~$ python2.7 -c 'import locale; locale.normalize(u"en_US")'
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/usr/lib/python2.7/locale.py", line 358, in normalize
    fullname = localename.translate(_ascii_lower_map)
TypeError: character mapping must return integer, None or unicode

with python2.6 it works and it also works with non-unicode strings in 2.7

this is a regression introduced by fixing http://bugs.python.org/issue1813

This breaks some user code,. e.g. wx.Locale.GetCanonicalName returns unicode.
Example bugs:
https://bugs.launchpad.net/ubuntu/+source/update-manager/+bug/824734
https://bugs.launchpad.net/ubuntu/+source/playonlinux/+bug/825421

Julian Taylor wrote:
> 
> New submission from Julian Taylor <jtaylor.debian@googlemail.com>:
> 
> using unicode strings for locale.normalize gives following traceback with python2.7:
> 
> ~$ python2.7 -c 'import locale; locale.normalize(u"en_US")'
> Traceback (most recent call last):
>   File "<string>", line 1, in <module>
>   File "/usr/lib/python2.7/locale.py", line 358, in normalize
>     fullname = localename.translate(_ascii_lower_map)
> TypeError: character mapping must return integer, None or unicode
> 
> with python2.6 it works and it also works with non-unicode strings in 2.7

This looks like a side-effect of the change Antoine made to the locale
module when trying to make the case mapping work in a non-locale
dependent way.

A cheap way of fixing this would be to test for str-ness of localename and if it's a unicode, just localname.encode('ascii')

Or is that completely insane?

For example:


diff -r fb49394f75ed Lib/locale.py
--- a/Lib/locale.py	Mon Aug 15 14:24:15 2011 +0300
+++ b/Lib/locale.py	Mon Aug 15 16:47:23 2011 -0400
@@ -355,6 +355,8 @@
 
     """
     # Normalize the locale name and extract the encoding
+    if isinstance(localename, unicode):
+        localename = localename.encode('ascii')
     fullname = localename.translate(_ascii_lower_map)
     if ':' in fullname:
         # ':' is sometimes used as encoding delimiter.
diff -r fb49394f75ed Lib/test/test_locale.py
--- a/Lib/test/test_locale.py	Mon Aug 15 14:24:15 2011 +0300
+++ b/Lib/test/test_locale.py	Mon Aug 15 16:47:23 2011 -0400
@@ -412,6 +412,11 @@
         locale.setlocale(locale.LC_CTYPE, loc)
         self.assertEqual(loc, locale.getlocale())
 
+    def test_normalize_issue12752(self):
+        # Issue #1813 caused a regression where locale.normalize() would no
+        # longer accept unicode strings.
+        self.assertEqual(locale.normalize(u'en_US'), 'en_US.ISO8859-1')
+
 
 def test_main():
     tests = [

The proposed resolution looks ok. Another possibility is simply to use .lower() if the string is an unicode string, since that will bypass the C locale.

New changeset 0d64fe6c737f by Barry Warsaw in branch '2.7':
The simplest possible fix for the regression in bug 12752 by encoding unicodes
http://hg.python.org/cpython/rev/0d64fe6c737f