schemes: move re construction to module-level and python3-ify

This makes the schemes extension load correctly in Python 3.

hgext/schemes.py

@@ -1,133 +1,134
 # Copyright 2009, Alexander Solovyov <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
 """extend schemes with shortcuts to repository swarms
 
 This extension allows you to specify shortcuts for parent URLs with a
 lot of repositories to act like a scheme, for example::
 
   [schemes]
   py = http://code.python.org/hg/
 
 After that you can use it like::
 
   hg clone py://trunk/
 
 Additionally there is support for some more complex schemas, for
 example used by Google Code::
 
   [schemes]
   gcode = http://{1}.googlecode.com/hg/
 
 The syntax is taken from Mercurial templates, and you have unlimited
 number of variables, starting with ``{1}`` and continuing with
 ``{2}``, ``{3}`` and so on. This variables will receive parts of URL
 supplied, split by ``/``. Anything not specified as ``{part}`` will be
 just appended to an URL.
 
 For convenience, the extension adds these schemes by default::
 
   [schemes]
   py = http://hg.python.org/
   bb = https://bitbucket.org/
   bb+ssh = ssh://[e-mail]/
   gcode = https://{1}.googlecode.com/hg/
   kiln = https://{1}.kilnhg.com/Repo/
 
 You can override a predefined scheme by defining a new scheme with the
 same name.
 """
 from __future__ import absolute_import
 
 import os
 import re
 
 from mercurial.i18n import _
 from mercurial import (
     cmdutil,
     error,
     extensions,
     hg,
     pycompat,
     templater,
     util,
 )
 
 cmdtable = {}
 command = cmdutil.command(cmdtable)
 # Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for
 # extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
 # be specifying the version(s) of Mercurial they are tested with, or
 # leave the attribute unspecified.
 testedwith = 'ships-with-hg-core'
 
+_partre = re.compile(r'\{(\d+)\}'.encode(u'latin1'))
 
 class ShortRepository(object):
     def __init__(self, url, scheme, templater):
         self.scheme = scheme
         self.templater = templater
         self.url = url
         try:
-            self.parts = max(map(int, re.findall(r'\{(\d+)\}', self.url)))
+            self.parts = max(map(int, _partre.findall(self.url)))
         except ValueError:
             self.parts = 0
 
     def __repr__(self):
         return '<ShortRepository: %s>' % self.scheme
 
     def instance(self, ui, url, create):
         url = self.resolve(url)
         return hg._peerlookup(url).instance(ui, url, create)
 
     def resolve(self, url):
         # Should this use the util.url class, or is manual parsing better?
         try:
             url = url.split('://', 1)[1]
         except IndexError:
             raise error.Abort(_("no '://' in scheme url '%s'") % url)
         parts = url.split('/', self.parts)
         if len(parts) > self.parts:
             tail = parts[-1]
             parts = parts[:-1]
         else:
             tail = ''
         context = dict((str(i + 1), v) for i, v in enumerate(parts))
         return ''.join(self.templater.process(self.url, context)) + tail
 
 def hasdriveletter(orig, path):
     if path:
         for scheme in schemes:
             if path.startswith(scheme + ':'):
                 return False
     return orig(path)
 
 schemes = {
     'py': 'http://hg.python.org/',
     'bb': 'https://bitbucket.org/',
     'bb+ssh': 'ssh://[e-mail]/',
     'gcode': 'https://{1}.googlecode.com/hg/',
     'kiln': 'https://{1}.kilnhg.com/Repo/'
     }
 
 def extsetup(ui):
     schemes.update(dict(ui.configitems('schemes')))
     t = templater.engine(lambda x: x)
     for scheme, url in schemes.items():
         if (pycompat.osname == 'nt' and len(scheme) == 1 and scheme.isalpha()
             and os.path.exists('%s:\\' % scheme)):
             raise error.Abort(_('custom scheme %s:// conflicts with drive '
                                'letter %s:\\\n') % (scheme, scheme.upper()))
         hg.schemes[scheme] = ShortRepository(url, scheme, t)
 
     extensions.wrapfunction(util, 'hasdriveletter', hasdriveletter)
 
 @command('debugexpandscheme', norepo=True)
 def expandscheme(ui, url, **opts):
     """given a repo path, provide the scheme-expanded path
     """
     repo = hg._peerlookup(url)
     if isinstance(repo, ShortRepository):
         url = repo.resolve(url)
     ui.write(url + '\n')