largefiles: make the protocol hack for replacing heads with lheads more precise

Before the hack would replace 'heads' with 'lheads' no matter where it occured
in a batch command string.

Instead we will use a regexp to more carefully only match the 'heads' commands.

hgext/largefiles/proto.py

@@ -1,174 +1,177 b''
 # Copyright 2011 Fog Creek Software
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
 import os
 import urllib2
+import re
 
 from mercurial import error, httppeer, util, wireproto
 from mercurial.wireproto import batchable, future
 from mercurial.i18n import _
 
 import lfutil
 
 LARGEFILES_REQUIRED_MSG = ('\nThis repository uses the largefiles extension.'
                            '\n\nPlease enable it in your Mercurial config '
                            'file.\n')
 
 # these will all be replaced by largefiles.uisetup
 capabilitiesorig = None
 ssholdcallstream = None
 httpoldcallstream = None
 
 def putlfile(repo, proto, sha):
     '''Put a largefile into a repository's local store and into the
     user cache.'''
     proto.redirect()
 
     path = lfutil.storepath(repo, sha)
     util.makedirs(os.path.dirname(path))
     tmpfp = util.atomictempfile(path, createmode=repo.store.createmode)
 
     try:
         try:
             proto.getfile(tmpfp)
             tmpfp._fp.seek(0)
             if sha != lfutil.hexsha1(tmpfp._fp):
                 raise IOError(0, _('largefile contents do not match hash'))
             tmpfp.close()
             lfutil.linktousercache(repo, sha)
         except IOError, e:
             repo.ui.warn(_('largefiles: failed to put %s into store: %s') %
                          (sha, e.strerror))
             return wireproto.pushres(1)
     finally:
         tmpfp.discard()
 
     return wireproto.pushres(0)
 
 def getlfile(repo, proto, sha):
     '''Retrieve a largefile from the repository-local cache or system
     cache.'''
     filename = lfutil.findfile(repo, sha)
     if not filename:
         raise util.Abort(_('requested largefile %s not present in cache') % sha)
     f = open(filename, 'rb')
     length = os.fstat(f.fileno())[6]
 
     # Since we can't set an HTTP content-length header here, and
     # Mercurial core provides no way to give the length of a streamres
     # (and reading the entire file into RAM would be ill-advised), we
     # just send the length on the first line of the response, like the
     # ssh proto does for string responses.
     def generator():
         yield '%d\n' % length
         for chunk in util.filechunkiter(f):
             yield chunk
     return wireproto.streamres(generator())
 
 def statlfile(repo, proto, sha):
     '''Return '2\n' if the largefile is missing, '0\n' if it seems to be in
     good condition.
 
     The value 1 is reserved for mismatched checksum, but that is too expensive
     to be verified on every stat and must be caught be running 'hg verify'
     server side.'''
     filename = lfutil.findfile(repo, sha)
     if not filename:
         return '2\n'
     return '0\n'
 
 def wirereposetup(ui, repo):
     class lfileswirerepository(repo.__class__):
         def putlfile(self, sha, fd):
             # unfortunately, httprepository._callpush tries to convert its
             # input file-like into a bundle before sending it, so we can't use
             # it ...
             if issubclass(self.__class__, httppeer.httppeer):
                 res = None
                 try:
                     res = self._call('putlfile', data=fd, sha=sha,
                         headers={'content-type':'application/mercurial-0.1'})
                     d, output = res.split('\n', 1)
                     for l in output.splitlines(True):
                         self.ui.warn(_('remote: '), l, '\n')
                     return int(d)
                 except (ValueError, urllib2.HTTPError):
                     self.ui.warn(_('unexpected putlfile response: %s') % res)
                     return 1
             # ... but we can't use sshrepository._call because the data=
             # argument won't get sent, and _callpush does exactly what we want
             # in this case: send the data straight through
             else:
                 try:
                     ret, output = self._callpush("putlfile", fd, sha=sha)
                     if ret == "":
                         raise error.ResponseError(_('putlfile failed:'),
                                 output)
                     return int(ret)
                 except IOError:
                     return 1
                 except ValueError:
                     raise error.ResponseError(
                         _('putlfile failed (unexpected response):'), ret)
 
         def getlfile(self, sha):
             """returns an iterable with the chunks of the file with sha sha"""
             stream = self._callstream("getlfile", sha=sha)
             length = stream.readline()
             try:
                 length = int(length)
             except ValueError:
                 self._abort(error.ResponseError(_("unexpected response:"),
                                                 length))
 
             # SSH streams will block if reading more than length
             for chunk in util.filechunkiter(stream, 128 * 1024, length):
                 yield chunk
             # HTTP streams must hit the end to process the last empty
             # chunk of Chunked-Encoding so the connection can be reused.
             if issubclass(self.__class__, httppeer.httppeer):
                 chunk = stream.read(1)
                 if chunk:
                     self._abort(error.ResponseError(_("unexpected response:"),
                                                     chunk))
 
         @batchable
         def statlfile(self, sha):
             f = future()
             result = {'sha': sha}
             yield result, f
             try:
                 yield int(f.value)
             except (ValueError, urllib2.HTTPError):
                 # If the server returns anything but an integer followed by a
                 # newline, newline, it's not speaking our language; if we get
                 # an HTTP error, we can't be sure the largefile is present;
                 # either way, consider it missing.
                 yield 2
 
     repo.__class__ = lfileswirerepository
 
 # advertise the largefiles=serve capability
 def capabilities(repo, proto):
     return capabilitiesorig(repo, proto) + ' largefiles=serve'
 
 def heads(repo, proto):
     if lfutil.islfilesrepo(repo):
         return wireproto.ooberror(LARGEFILES_REQUIRED_MSG)
     return wireproto.heads(repo, proto)
 
 def sshrepocallstream(self, cmd, **args):
     if cmd == 'heads' and self.capable('largefiles'):
         cmd = 'lheads'
     if cmd == 'batch' and self.capable('largefiles'):
         args['cmds'] = args['cmds'].replace('heads ', 'lheads ')
     return ssholdcallstream(self, cmd, **args)
 
+headsre = re.compile(r'(^|;)heads\b')
+
 def httprepocallstream(self, cmd, **args):
     if cmd == 'heads' and self.capable('largefiles'):
         cmd = 'lheads'
     if cmd == 'batch' and self.capable('largefiles'):
-        args['cmds'] = args['cmds'].replace('heads ', 'lheads ')
+        args['cmds'] = headsre.sub('lheads', args['cmds'])
     return httpoldcallstream(self, cmd, **args)