py3: replace sys.executable with pycompat.sysexecutable

sys.executable returns unicodes on Python 3. This patch replaces occurences of
sys.executable with pycompat.sysexecutable.

mercurial/chgserver.py

@@ -1,644 +1,644
 # chgserver.py - command server extension for cHg
 #
 # Copyright 2011 Yuya Nishihara <[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.
 
 """command server extension for cHg
 
 'S' channel (read/write)
     propagate ui.system() request to client
 
 'attachio' command
     attach client's stdio passed by sendmsg()
 
 'chdir' command
     change current directory
 
 'getpager' command
     checks if pager is enabled and which pager should be executed
 
 'setenv' command
     replace os.environ completely
 
 'setumask' command
     set umask
 
 'validate' command
     reload the config and check if the server is up to date
 
 Config
 ------
 
 ::
 
   [chgserver]
   idletimeout = 3600 # seconds, after which an idle server will exit
   skiphash = False   # whether to skip config or env change checks
 """
 
 from __future__ import absolute_import
 
 import errno
 import hashlib
 import inspect
 import os
 import re
 import signal
 import struct
-import sys
 import time
 
 from .i18n import _
 
 from . import (
     cmdutil,
     commandserver,
     encoding,
     error,
     extensions,
     osutil,
+    pycompat,
     util,
 )
 
 _log = commandserver.log
 
 def _hashlist(items):
     """return sha1 hexdigest for a list"""
     return hashlib.sha1(str(items)).hexdigest()
 
 # sensitive config sections affecting confighash
 _configsections = [
     'alias',  # affects global state commands.table
     'extdiff',  # uisetup will register new commands
     'extensions',
 ]
 
 # sensitive environment variables affecting confighash
 _envre = re.compile(r'''\A(?:
                     CHGHG
                     |HG(?:[A-Z].*)?
                     |LANG(?:UAGE)?
                     |LC_.*
                     |LD_.*
                     |PATH
                     |PYTHON.*
                     |TERM(?:INFO)?
                     |TZ
                     )\Z''', re.X)
 
 def _confighash(ui):
     """return a quick hash for detecting config/env changes
 
     confighash is the hash of sensitive config items and environment variables.
 
     for chgserver, it is designed that once confighash changes, the server is
     not qualified to serve its client and should redirect the client to a new
     server. different from mtimehash, confighash change will not mark the
     server outdated and exit since the user can have different configs at the
     same time.
     """
     sectionitems = []
     for section in _configsections:
         sectionitems.append(ui.configitems(section))
     sectionhash = _hashlist(sectionitems)
     envitems = [(k, v) for k, v in encoding.environ.iteritems()
                 if _envre.match(k)]
     envhash = _hashlist(sorted(envitems))
     return sectionhash[:6] + envhash[:6]
 
 def _getmtimepaths(ui):
     """get a list of paths that should be checked to detect change
 
     The list will include:
     - extensions (will not cover all files for complex extensions)
     - mercurial/__version__.py
     - python binary
     """
     modules = [m for n, m in extensions.extensions(ui)]
     try:
         from . import __version__
         modules.append(__version__)
     except ImportError:
         pass
-    files = [sys.executable]
+    files = [pycompat.sysexecutable]
     for m in modules:
         try:
             files.append(inspect.getabsfile(m))
         except TypeError:
             pass
     return sorted(set(files))
 
 def _mtimehash(paths):
     """return a quick hash for detecting file changes
 
     mtimehash calls stat on given paths and calculate a hash based on size and
     mtime of each file. mtimehash does not read file content because reading is
     expensive. therefore it's not 100% reliable for detecting content changes.
     it's possible to return different hashes for same file contents.
     it's also possible to return a same hash for different file contents for
     some carefully crafted situation.
 
     for chgserver, it is designed that once mtimehash changes, the server is
     considered outdated immediately and should no longer provide service.
 
     mtimehash is not included in confighash because we only know the paths of
     extensions after importing them (there is imp.find_module but that faces
     race conditions). We need to calculate confighash without importing.
     """
     def trystat(path):
         try:
             st = os.stat(path)
             return (st.st_mtime, st.st_size)
         except OSError:
             # could be ENOENT, EPERM etc. not fatal in any case
             pass
     return _hashlist(map(trystat, paths))[:12]
 
 class hashstate(object):
     """a structure storing confighash, mtimehash, paths used for mtimehash"""
     def __init__(self, confighash, mtimehash, mtimepaths):
         self.confighash = confighash
         self.mtimehash = mtimehash
         self.mtimepaths = mtimepaths
 
     @staticmethod
     def fromui(ui, mtimepaths=None):
         if mtimepaths is None:
             mtimepaths = _getmtimepaths(ui)
         confighash = _confighash(ui)
         mtimehash = _mtimehash(mtimepaths)
         _log('confighash = %s mtimehash = %s\n' % (confighash, mtimehash))
         return hashstate(confighash, mtimehash, mtimepaths)
 
 # copied from hgext/pager.py:uisetup()
 def _setuppagercmd(ui, options, cmd):
     from . import commands  # avoid cycle
 
     if not ui.formatted():
         return
 
     p = ui.config("pager", "pager", encoding.environ.get("PAGER"))
     usepager = False
     always = util.parsebool(options['pager'])
     auto = options['pager'] == 'auto'
 
     if not p:
         pass
     elif always:
         usepager = True
     elif not auto:
         usepager = False
     else:
         attended = ['annotate', 'cat', 'diff', 'export', 'glog', 'log', 'qdiff']
         attend = ui.configlist('pager', 'attend', attended)
         ignore = ui.configlist('pager', 'ignore')
         cmds, _ = cmdutil.findcmd(cmd, commands.table)
 
         for cmd in cmds:
             var = 'attend-%s' % cmd
             if ui.config('pager', var):
                 usepager = ui.configbool('pager', var)
                 break
             if (cmd in attend or
                 (cmd not in ignore and not attend)):
                 usepager = True
                 break
 
     if usepager:
         ui.setconfig('ui', 'formatted', ui.formatted(), 'pager')
         ui.setconfig('ui', 'interactive', False, 'pager')
         return p
 
 def _newchgui(srcui, csystem):
     class chgui(srcui.__class__):
         def __init__(self, src=None):
             super(chgui, self).__init__(src)
             if src:
                 self._csystem = getattr(src, '_csystem', csystem)
             else:
                 self._csystem = csystem
 
         def system(self, cmd, environ=None, cwd=None, onerr=None,
                    errprefix=None):
             # fallback to the original system method if the output needs to be
             # captured (to self._buffers), or the output stream is not stdout
             # (e.g. stderr, cStringIO), because the chg client is not aware of
             # these situations and will behave differently (write to stdout).
             if (any(s[1] for s in self._bufferstates)
                 or not util.safehasattr(self.fout, 'fileno')
                 or self.fout.fileno() != util.stdout.fileno()):
                 return super(chgui, self).system(cmd, environ, cwd, onerr,
                                                  errprefix)
             # copied from mercurial/util.py:system()
             self.flush()
             def py2shell(val):
                 if val is None or val is False:
                     return '0'
                 if val is True:
                     return '1'
                 return str(val)
             env = encoding.environ.copy()
             if environ:
                 env.update((k, py2shell(v)) for k, v in environ.iteritems())
             env['HG'] = util.hgexecutable()
             rc = self._csystem(cmd, env, cwd)
             if rc and onerr:
                 errmsg = '%s %s' % (os.path.basename(cmd.split(None, 1)[0]),
                                     util.explainexit(rc)[0])
                 if errprefix:
                     errmsg = '%s: %s' % (errprefix, errmsg)
                 raise onerr(errmsg)
             return rc
 
     return chgui(srcui)
 
 def _loadnewui(srcui, args):
     from . import dispatch  # avoid cycle
 
     newui = srcui.__class__.load()
     for a in ['fin', 'fout', 'ferr', 'environ']:
         setattr(newui, a, getattr(srcui, a))
     if util.safehasattr(srcui, '_csystem'):
         newui._csystem = srcui._csystem
 
     # command line args
     args = args[:]
     dispatch._parseconfig(newui, dispatch._earlygetopt(['--config'], args))
 
     # stolen from tortoisehg.util.copydynamicconfig()
     for section, name, value in srcui.walkconfig():
         source = srcui.configsource(section, name)
         if ':' in source or source == '--config':
             # path:line or command line
             continue
         newui.setconfig(section, name, value, source)
 
     # load wd and repo config, copied from dispatch.py
     cwds = dispatch._earlygetopt(['--cwd'], args)
     cwd = cwds and os.path.realpath(cwds[-1]) or None
     rpath = dispatch._earlygetopt(["-R", "--repository", "--repo"], args)
     path, newlui = dispatch._getlocal(newui, rpath, wd=cwd)
 
     return (newui, newlui)
 
 class channeledsystem(object):
     """Propagate ui.system() request in the following format:
 
     payload length (unsigned int),
     cmd, '\0',
     cwd, '\0',
     envkey, '=', val, '\0',
     ...
     envkey, '=', val
 
     and waits:
 
     exitcode length (unsigned int),
     exitcode (int)
     """
     def __init__(self, in_, out, channel):
         self.in_ = in_
         self.out = out
         self.channel = channel
 
     def __call__(self, cmd, environ, cwd):
         args = [util.quotecommand(cmd), os.path.abspath(cwd or '.')]
         args.extend('%s=%s' % (k, v) for k, v in environ.iteritems())
         data = '\0'.join(args)
         self.out.write(struct.pack('>cI', self.channel, len(data)))
         self.out.write(data)
         self.out.flush()
 
         length = self.in_.read(4)
         length, = struct.unpack('>I', length)
         if length != 4:
             raise error.Abort(_('invalid response'))
         rc, = struct.unpack('>i', self.in_.read(4))
         return rc
 
 _iochannels = [
     # server.ch, ui.fp, mode
     ('cin', 'fin', 'rb'),
     ('cout', 'fout', 'wb'),
     ('cerr', 'ferr', 'wb'),
 ]
 
 class chgcmdserver(commandserver.server):
     def __init__(self, ui, repo, fin, fout, sock, hashstate, baseaddress):
         super(chgcmdserver, self).__init__(
             _newchgui(ui, channeledsystem(fin, fout, 'S')), repo, fin, fout)
         self.clientsock = sock
         self._oldios = []  # original (self.ch, ui.fp, fd) before "attachio"
         self.hashstate = hashstate
         self.baseaddress = baseaddress
         if hashstate is not None:
             self.capabilities = self.capabilities.copy()
             self.capabilities['validate'] = chgcmdserver.validate
 
     def cleanup(self):
         super(chgcmdserver, self).cleanup()
         # dispatch._runcatch() does not flush outputs if exception is not
         # handled by dispatch._dispatch()
         self.ui.flush()
         self._restoreio()
 
     def attachio(self):
         """Attach to client's stdio passed via unix domain socket; all
         channels except cresult will no longer be used
         """
         # tell client to sendmsg() with 1-byte payload, which makes it
         # distinctive from "attachio\n" command consumed by client.read()
         self.clientsock.sendall(struct.pack('>cI', 'I', 1))
         clientfds = osutil.recvfds(self.clientsock.fileno())
         _log('received fds: %r\n' % clientfds)
 
         ui = self.ui
         ui.flush()
         first = self._saveio()
         for fd, (cn, fn, mode) in zip(clientfds, _iochannels):
             assert fd > 0
             fp = getattr(ui, fn)
             os.dup2(fd, fp.fileno())
             os.close(fd)
             if not first:
                 continue
             # reset buffering mode when client is first attached. as we want
             # to see output immediately on pager, the mode stays unchanged
             # when client re-attached. ferr is unchanged because it should
             # be unbuffered no matter if it is a tty or not.
             if fn == 'ferr':
                 newfp = fp
             else:
                 # make it line buffered explicitly because the default is
                 # decided on first write(), where fout could be a pager.
                 if fp.isatty():
                     bufsize = 1  # line buffered
                 else:
                     bufsize = -1  # system default
                 newfp = os.fdopen(fp.fileno(), mode, bufsize)
                 setattr(ui, fn, newfp)
             setattr(self, cn, newfp)
 
         self.cresult.write(struct.pack('>i', len(clientfds)))
 
     def _saveio(self):
         if self._oldios:
             return False
         ui = self.ui
         for cn, fn, _mode in _iochannels:
             ch = getattr(self, cn)
             fp = getattr(ui, fn)
             fd = os.dup(fp.fileno())
             self._oldios.append((ch, fp, fd))
         return True
 
     def _restoreio(self):
         ui = self.ui
         for (ch, fp, fd), (cn, fn, _mode) in zip(self._oldios, _iochannels):
             newfp = getattr(ui, fn)
             # close newfp while it's associated with client; otherwise it
             # would be closed when newfp is deleted
             if newfp is not fp:
                 newfp.close()
             # restore original fd: fp is open again
             os.dup2(fd, fp.fileno())
             os.close(fd)
             setattr(self, cn, ch)
             setattr(ui, fn, fp)
         del self._oldios[:]
 
     def validate(self):
         """Reload the config and check if the server is up to date
 
         Read a list of '\0' separated arguments.
         Write a non-empty list of '\0' separated instruction strings or '\0'
         if the list is empty.
         An instruction string could be either:
             - "unlink $path", the client should unlink the path to stop the
               outdated server.
             - "redirect $path", the client should attempt to connect to $path
               first. If it does not work, start a new server. It implies
               "reconnect".
             - "exit $n", the client should exit directly with code n.
               This may happen if we cannot parse the config.
             - "reconnect", the client should close the connection and
               reconnect.
         If neither "reconnect" nor "redirect" is included in the instruction
         list, the client can continue with this server after completing all
         the instructions.
         """
         from . import dispatch  # avoid cycle
 
         args = self._readlist()
         try:
             self.ui, lui = _loadnewui(self.ui, args)
         except error.ParseError as inst:
             dispatch._formatparse(self.ui.warn, inst)
             self.ui.flush()
             self.cresult.write('exit 255')
             return
         newhash = hashstate.fromui(lui, self.hashstate.mtimepaths)
         insts = []
         if newhash.mtimehash != self.hashstate.mtimehash:
             addr = _hashaddress(self.baseaddress, self.hashstate.confighash)
             insts.append('unlink %s' % addr)
             # mtimehash is empty if one or more extensions fail to load.
             # to be compatible with hg, still serve the client this time.
             if self.hashstate.mtimehash:
                 insts.append('reconnect')
         if newhash.confighash != self.hashstate.confighash:
             addr = _hashaddress(self.baseaddress, newhash.confighash)
             insts.append('redirect %s' % addr)
         _log('validate: %s\n' % insts)
         self.cresult.write('\0'.join(insts) or '\0')
 
     def chdir(self):
         """Change current directory
 
         Note that the behavior of --cwd option is bit different from this.
         It does not affect --config parameter.
         """
         path = self._readstr()
         if not path:
             return
         _log('chdir to %r\n' % path)
         os.chdir(path)
 
     def setumask(self):
         """Change umask"""
         mask = struct.unpack('>I', self._read(4))[0]
         _log('setumask %r\n' % mask)
         os.umask(mask)
 
     def getpager(self):
         """Read cmdargs and write pager command to r-channel if enabled
 
         If pager isn't enabled, this writes '\0' because channeledoutput
         does not allow to write empty data.
         """
         from . import dispatch  # avoid cycle
 
         args = self._readlist()
         try:
             cmd, _func, args, options, _cmdoptions = dispatch._parse(self.ui,
                                                                      args)
         except (error.Abort, error.AmbiguousCommand, error.CommandError,
                 error.UnknownCommand):
             cmd = None
             options = {}
         if not cmd or 'pager' not in options:
             self.cresult.write('\0')
             return
 
         pagercmd = _setuppagercmd(self.ui, options, cmd)
         if pagercmd:
             # Python's SIGPIPE is SIG_IGN by default. change to SIG_DFL so
             # we can exit if the pipe to the pager is closed
             if util.safehasattr(signal, 'SIGPIPE') and \
                     signal.getsignal(signal.SIGPIPE) == signal.SIG_IGN:
                 signal.signal(signal.SIGPIPE, signal.SIG_DFL)
             self.cresult.write(pagercmd)
         else:
             self.cresult.write('\0')
 
     def runcommand(self):
         return super(chgcmdserver, self).runcommand()
 
     def setenv(self):
         """Clear and update os.environ
 
         Note that not all variables can make an effect on the running process.
         """
         l = self._readlist()
         try:
             newenv = dict(s.split('=', 1) for s in l)
         except ValueError:
             raise ValueError('unexpected value in setenv request')
         _log('setenv: %r\n' % sorted(newenv.keys()))
         encoding.environ.clear()
         encoding.environ.update(newenv)
 
     capabilities = commandserver.server.capabilities.copy()
     capabilities.update({'attachio': attachio,
                          'chdir': chdir,
                          'getpager': getpager,
                          'runcommand': runcommand,
                          'setenv': setenv,
                          'setumask': setumask})
 
 def _tempaddress(address):
     return '%s.%d.tmp' % (address, os.getpid())
 
 def _hashaddress(address, hashstr):
     # if the basename of address contains '.', use only the left part. this
     # makes it possible for the client to pass 'server.tmp$PID' and follow by
     # an atomic rename to avoid locking when spawning new servers.
     dirname, basename = os.path.split(address)
     basename = basename.split('.', 1)[0]
     return '%s-%s' % (os.path.join(dirname, basename), hashstr)
 
 class chgunixservicehandler(object):
     """Set of operations for chg services"""
 
     pollinterval = 1  # [sec]
 
     def __init__(self, ui):
         self.ui = ui
         self._idletimeout = ui.configint('chgserver', 'idletimeout', 3600)
         self._lastactive = time.time()
 
     def bindsocket(self, sock, address):
         self._inithashstate(address)
         self._checkextensions()
         self._bind(sock)
         self._createsymlink()
 
     def _inithashstate(self, address):
         self._baseaddress = address
         if self.ui.configbool('chgserver', 'skiphash', False):
             self._hashstate = None
             self._realaddress = address
             return
         self._hashstate = hashstate.fromui(self.ui)
         self._realaddress = _hashaddress(address, self._hashstate.confighash)
 
     def _checkextensions(self):
         if not self._hashstate:
             return
         if extensions.notloaded():
             # one or more extensions failed to load. mtimehash becomes
             # meaningless because we do not know the paths of those extensions.
             # set mtimehash to an illegal hash value to invalidate the server.
             self._hashstate.mtimehash = ''
 
     def _bind(self, sock):
         # use a unique temp address so we can stat the file and do ownership
         # check later
         tempaddress = _tempaddress(self._realaddress)
         util.bindunixsocket(sock, tempaddress)
         self._socketstat = os.stat(tempaddress)
         # rename will replace the old socket file if exists atomically. the
         # old server will detect ownership change and exit.
         util.rename(tempaddress, self._realaddress)
 
     def _createsymlink(self):
         if self._baseaddress == self._realaddress:
             return
         tempaddress = _tempaddress(self._baseaddress)
         os.symlink(os.path.basename(self._realaddress), tempaddress)
         util.rename(tempaddress, self._baseaddress)
 
     def _issocketowner(self):
         try:
             stat = os.stat(self._realaddress)
             return (stat.st_ino == self._socketstat.st_ino and
                     stat.st_mtime == self._socketstat.st_mtime)
         except OSError:
             return False
 
     def unlinksocket(self, address):
         if not self._issocketowner():
             return
         # it is possible to have a race condition here that we may
         # remove another server's socket file. but that's okay
         # since that server will detect and exit automatically and
         # the client will start a new server on demand.
         try:
             os.unlink(self._realaddress)
         except OSError as exc:
             if exc.errno != errno.ENOENT:
                 raise
 
     def printbanner(self, address):
         # no "listening at" message should be printed to simulate hg behavior
         pass
 
     def shouldexit(self):
         if not self._issocketowner():
             self.ui.debug('%s is not owned, exiting.\n' % self._realaddress)
             return True
         if time.time() - self._lastactive > self._idletimeout:
             self.ui.debug('being idle too long. exiting.\n')
             return True
         return False
 
     def newconnection(self):
         self._lastactive = time.time()
 
     def createcmdserver(self, repo, conn, fin, fout):
         return chgcmdserver(self.ui, repo, fin, fout, conn,
                             self._hashstate, self._baseaddress)
 
 def chgunixservice(ui, repo, opts):
     # CHGINTERNALMARK is temporarily set by chg client to detect if chg will
     # start another chg. drop it to avoid possible side effects.
     if 'CHGINTERNALMARK' in encoding.environ:
         del encoding.environ['CHGINTERNALMARK']
 
     if repo:
         # one chgserver can serve multiple repos. drop repo information
         ui.setconfig('bundle', 'mainreporoot', '', 'repo')
     h = chgunixservicehandler(ui)
     return commandserver.unixforkingservice(ui, repo=None, opts=opts, handler=h)

mercurial/commands.py

@@ -1,6601 +1,6601
 # commands.py - command processing for mercurial
 #
 # Copyright 2005-2007 Matt Mackall <[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.
 
 from __future__ import absolute_import
 
 import difflib
 import errno
 import os
 import re
 import shlex
 import socket
 import string
 import sys
 import tempfile
 import time
 
 from .i18n import _
 from .node import (
     bin,
     hex,
     nullhex,
     nullid,
     nullrev,
     short,
 )
 from . import (
     archival,
     bookmarks,
     bundle2,
     changegroup,
     cmdutil,
     copies,
     destutil,
     dirstateguard,
     discovery,
     encoding,
     error,
     exchange,
     extensions,
     formatter,
     graphmod,
     hbisect,
     help,
     hg,
     lock as lockmod,
     merge as mergemod,
     minirst,
     obsolete,
     patch,
     phases,
     policy,
     pvec,
     pycompat,
     repair,
     revlog,
     revset,
     scmutil,
     server,
     sshserver,
     sslutil,
     streamclone,
     templatekw,
     templater,
     ui as uimod,
     util,
 )
 
 release = lockmod.release
 
 table = {}
 
 command = cmdutil.command(table)
 
 # label constants
 # until 3.5, bookmarks.current was the advertised name, not
 # bookmarks.active, so we must use both to avoid breaking old
 # custom styles
 activebookmarklabel = 'bookmarks.active bookmarks.current'
 
 # common command options
 
 globalopts = [
     ('R', 'repository', '',
      _('repository root directory or name of overlay bundle file'),
      _('REPO')),
     ('', 'cwd', '',
      _('change working directory'), _('DIR')),
     ('y', 'noninteractive', None,
      _('do not prompt, automatically pick the first choice for all prompts')),
     ('q', 'quiet', None, _('suppress output')),
     ('v', 'verbose', None, _('enable additional output')),
     ('', 'config', [],
      _('set/override config option (use \'section.name=value\')'),
      _('CONFIG')),
     ('', 'debug', None, _('enable debugging output')),
     ('', 'debugger', None, _('start debugger')),
     ('', 'encoding', encoding.encoding, _('set the charset encoding'),
      _('ENCODE')),
     ('', 'encodingmode', encoding.encodingmode,
      _('set the charset encoding mode'), _('MODE')),
     ('', 'traceback', None, _('always print a traceback on exception')),
     ('', 'time', None, _('time how long the command takes')),
     ('', 'profile', None, _('print command execution profile')),
     ('', 'version', None, _('output version information and exit')),
     ('h', 'help', None, _('display help and exit')),
     ('', 'hidden', False, _('consider hidden changesets')),
 ]
 
 dryrunopts = [('n', 'dry-run', None,
                _('do not perform actions, just print output'))]
 
 remoteopts = [
     ('e', 'ssh', '',
      _('specify ssh command to use'), _('CMD')),
     ('', 'remotecmd', '',
      _('specify hg command to run on the remote side'), _('CMD')),
     ('', 'insecure', None,
      _('do not verify server certificate (ignoring web.cacerts config)')),
 ]
 
 walkopts = [
     ('I', 'include', [],
      _('include names matching the given patterns'), _('PATTERN')),
     ('X', 'exclude', [],
      _('exclude names matching the given patterns'), _('PATTERN')),
 ]
 
 commitopts = [
     ('m', 'message', '',
      _('use text as commit message'), _('TEXT')),
     ('l', 'logfile', '',
      _('read commit message from file'), _('FILE')),
 ]
 
 commitopts2 = [
     ('d', 'date', '',
      _('record the specified date as commit date'), _('DATE')),
     ('u', 'user', '',
      _('record the specified user as committer'), _('USER')),
 ]
 
 # hidden for now
 formatteropts = [
     ('T', 'template', '',
      _('display with template (EXPERIMENTAL)'), _('TEMPLATE')),
 ]
 
 templateopts = [
     ('', 'style', '',
      _('display using template map file (DEPRECATED)'), _('STYLE')),
     ('T', 'template', '',
      _('display with template'), _('TEMPLATE')),
 ]
 
 logopts = [
     ('p', 'patch', None, _('show patch')),
     ('g', 'git', None, _('use git extended diff format')),
     ('l', 'limit', '',
      _('limit number of changes displayed'), _('NUM')),
     ('M', 'no-merges', None, _('do not show merges')),
     ('', 'stat', None, _('output diffstat-style summary of changes')),
     ('G', 'graph', None, _("show the revision DAG")),
 ] + templateopts
 
 diffopts = [
     ('a', 'text', None, _('treat all files as text')),
     ('g', 'git', None, _('use git extended diff format')),
     ('', 'nodates', None, _('omit dates from diff headers'))
 ]
 
 diffwsopts = [
     ('w', 'ignore-all-space', None,
      _('ignore white space when comparing lines')),
     ('b', 'ignore-space-change', None,
      _('ignore changes in the amount of white space')),
     ('B', 'ignore-blank-lines', None,
      _('ignore changes whose lines are all blank')),
     ]
 
 diffopts2 = [
     ('', 'noprefix', None, _('omit a/ and b/ prefixes from filenames')),
     ('p', 'show-function', None, _('show which function each change is in')),
     ('', 'reverse', None, _('produce a diff that undoes the changes')),
     ] + diffwsopts + [
     ('U', 'unified', '',
      _('number of lines of context to show'), _('NUM')),
     ('', 'stat', None, _('output diffstat-style summary of changes')),
     ('', 'root', '', _('produce diffs relative to subdirectory'), _('DIR')),
 ]
 
 mergetoolopts = [
     ('t', 'tool', '', _('specify merge tool')),
 ]
 
 similarityopts = [
     ('s', 'similarity', '',
      _('guess renamed files by similarity (0<=s<=100)'), _('SIMILARITY'))
 ]
 
 subrepoopts = [
     ('S', 'subrepos', None,
      _('recurse into subrepositories'))
 ]
 
 debugrevlogopts = [
     ('c', 'changelog', False, _('open changelog')),
     ('m', 'manifest', False, _('open manifest')),
     ('', 'dir', '', _('open directory manifest')),
 ]
 
 # Commands start here, listed alphabetically
 
 @command('^add',
     walkopts + subrepoopts + dryrunopts,
     _('[OPTION]... [FILE]...'),
     inferrepo=True)
 def add(ui, repo, *pats, **opts):
     """add the specified files on the next commit
 
     Schedule files to be version controlled and added to the
     repository.
 
     The files will be added to the repository at the next commit. To
     undo an add before that, see :hg:`forget`.
 
     If no names are given, add all files to the repository (except
     files matching ``.hgignore``).
 
     .. container:: verbose
 
        Examples:
 
          - New (unknown) files are added
            automatically by :hg:`add`::
 
              $ ls
              foo.c
              $ hg status
              ? foo.c
              $ hg add
              adding foo.c
              $ hg status
              A foo.c
 
          - Specific files to be added can be specified::
 
              $ ls
              bar.c  foo.c
              $ hg status
              ? bar.c
              ? foo.c
              $ hg add bar.c
              $ hg status
              A bar.c
              ? foo.c
 
     Returns 0 if all files are successfully added.
     """
 
     m = scmutil.match(repo[None], pats, opts)
     rejected = cmdutil.add(ui, repo, m, "", False, **opts)
     return rejected and 1 or 0
 
 @command('addremove',
     similarityopts + subrepoopts + walkopts + dryrunopts,
     _('[OPTION]... [FILE]...'),
     inferrepo=True)
 def addremove(ui, repo, *pats, **opts):
     """add all new files, delete all missing files
 
     Add all new files and remove all missing files from the
     repository.
 
     Unless names are given, new files are ignored if they match any of
     the patterns in ``.hgignore``. As with add, these changes take
     effect at the next commit.
 
     Use the -s/--similarity option to detect renamed files. This
     option takes a percentage between 0 (disabled) and 100 (files must
     be identical) as its parameter. With a parameter greater than 0,
     this compares every removed file with every added file and records
     those similar enough as renames. Detecting renamed files this way
     can be expensive. After using this option, :hg:`status -C` can be
     used to check which files were identified as moved or renamed. If
     not specified, -s/--similarity defaults to 100 and only renames of
     identical files are detected.
 
     .. container:: verbose
 
        Examples:
 
          - A number of files (bar.c and foo.c) are new,
            while foobar.c has been removed (without using :hg:`remove`)
            from the repository::
 
              $ ls
              bar.c foo.c
              $ hg status
              ! foobar.c
              ? bar.c
              ? foo.c
              $ hg addremove
              adding bar.c
              adding foo.c
              removing foobar.c
              $ hg status
              A bar.c
              A foo.c
              R foobar.c
 
          - A file foobar.c was moved to foo.c without using :hg:`rename`.
            Afterwards, it was edited slightly::
 
              $ ls
              foo.c
              $ hg status
              ! foobar.c
              ? foo.c
              $ hg addremove --similarity 90
              removing foobar.c
              adding foo.c
              recording removal of foobar.c as rename to foo.c (94% similar)
              $ hg status -C
              A foo.c
                foobar.c
              R foobar.c
 
     Returns 0 if all files are successfully added.
     """
     try:
         sim = float(opts.get('similarity') or 100)
     except ValueError:
         raise error.Abort(_('similarity must be a number'))
     if sim < 0 or sim > 100:
         raise error.Abort(_('similarity must be between 0 and 100'))
     matcher = scmutil.match(repo[None], pats, opts)
     return scmutil.addremove(repo, matcher, "", opts, similarity=sim / 100.0)
 
 @command('^annotate|blame',
     [('r', 'rev', '', _('annotate the specified revision'), _('REV')),
     ('', 'follow', None,
      _('follow copies/renames and list the filename (DEPRECATED)')),
     ('', 'no-follow', None, _("don't follow copies and renames")),
     ('a', 'text', None, _('treat all files as text')),
     ('u', 'user', None, _('list the author (long with -v)')),
     ('f', 'file', None, _('list the filename')),
     ('d', 'date', None, _('list the date (short with -q)')),
     ('n', 'number', None, _('list the revision number (default)')),
     ('c', 'changeset', None, _('list the changeset')),
     ('l', 'line-number', None, _('show line number at the first appearance'))
     ] + diffwsopts + walkopts + formatteropts,
     _('[-r REV] [-f] [-a] [-u] [-d] [-n] [-c] [-l] FILE...'),
     inferrepo=True)
 def annotate(ui, repo, *pats, **opts):
     """show changeset information by line for each file
 
     List changes in files, showing the revision id responsible for
     each line.
 
     This command is useful for discovering when a change was made and
     by whom.
 
     If you include --file, --user, or --date, the revision number is
     suppressed unless you also include --number.
 
     Without the -a/--text option, annotate will avoid processing files
     it detects as binary. With -a, annotate will annotate the file
     anyway, although the results will probably be neither useful
     nor desirable.
 
     Returns 0 on success.
     """
     if not pats:
         raise error.Abort(_('at least one filename or pattern is required'))
 
     if opts.get('follow'):
         # --follow is deprecated and now just an alias for -f/--file
         # to mimic the behavior of Mercurial before version 1.5
         opts['file'] = True
 
     ctx = scmutil.revsingle(repo, opts.get('rev'))
 
     fm = ui.formatter('annotate', opts)
     if ui.quiet:
         datefunc = util.shortdate
     else:
         datefunc = util.datestr
     if ctx.rev() is None:
         def hexfn(node):
             if node is None:
                 return None
             else:
                 return fm.hexfunc(node)
         if opts.get('changeset'):
             # omit "+" suffix which is appended to node hex
             def formatrev(rev):
                 if rev is None:
                     return '%d' % ctx.p1().rev()
                 else:
                     return '%d' % rev
         else:
             def formatrev(rev):
                 if rev is None:
                     return '%d+' % ctx.p1().rev()
                 else:
                     return '%d ' % rev
         def formathex(hex):
             if hex is None:
                 return '%s+' % fm.hexfunc(ctx.p1().node())
             else:
                 return '%s ' % hex
     else:
         hexfn = fm.hexfunc
         formatrev = formathex = str
 
     opmap = [('user', ' ', lambda x: x[0].user(), ui.shortuser),
              ('number', ' ', lambda x: x[0].rev(), formatrev),
              ('changeset', ' ', lambda x: hexfn(x[0].node()), formathex),
              ('date', ' ', lambda x: x[0].date(), util.cachefunc(datefunc)),
              ('file', ' ', lambda x: x[0].path(), str),
              ('line_number', ':', lambda x: x[1], str),
             ]
     fieldnamemap = {'number': 'rev', 'changeset': 'node'}
 
     if (not opts.get('user') and not opts.get('changeset')
         and not opts.get('date') and not opts.get('file')):
         opts['number'] = True
 
     linenumber = opts.get('line_number') is not None
     if linenumber and (not opts.get('changeset')) and (not opts.get('number')):
         raise error.Abort(_('at least one of -n/-c is required for -l'))
 
     if fm.isplain():
         def makefunc(get, fmt):
             return lambda x: fmt(get(x))
     else:
         def makefunc(get, fmt):
             return get
     funcmap = [(makefunc(get, fmt), sep) for op, sep, get, fmt in opmap
                if opts.get(op)]
     funcmap[0] = (funcmap[0][0], '') # no separator in front of first column
     fields = ' '.join(fieldnamemap.get(op, op) for op, sep, get, fmt in opmap
                       if opts.get(op))
 
     def bad(x, y):
         raise error.Abort("%s: %s" % (x, y))
 
     m = scmutil.match(ctx, pats, opts, badfn=bad)
 
     follow = not opts.get('no_follow')
     diffopts = patch.difffeatureopts(ui, opts, section='annotate',
                                      whitespace=True)
     for abs in ctx.walk(m):
         fctx = ctx[abs]
         if not opts.get('text') and util.binary(fctx.data()):
             fm.plain(_("%s: binary file\n") % ((pats and m.rel(abs)) or abs))
             continue
 
         lines = fctx.annotate(follow=follow, linenumber=linenumber,
                               diffopts=diffopts)
         if not lines:
             continue
         formats = []
         pieces = []
 
         for f, sep in funcmap:
             l = [f(n) for n, dummy in lines]
             if fm.isplain():
                 sizes = [encoding.colwidth(x) for x in l]
                 ml = max(sizes)
                 formats.append([sep + ' ' * (ml - w) + '%s' for w in sizes])
             else:
                 formats.append(['%s' for x in l])
             pieces.append(l)
 
         for f, p, l in zip(zip(*formats), zip(*pieces), lines):
             fm.startitem()
             fm.write(fields, "".join(f), *p)
             fm.write('line', ": %s", l[1])
 
         if not lines[-1][1].endswith('\n'):
             fm.plain('\n')
 
     fm.end()
 
 @command('archive',
     [('', 'no-decode', None, _('do not pass files through decoders')),
     ('p', 'prefix', '', _('directory prefix for files in archive'),
      _('PREFIX')),
     ('r', 'rev', '', _('revision to distribute'), _('REV')),
     ('t', 'type', '', _('type of distribution to create'), _('TYPE')),
     ] + subrepoopts + walkopts,
     _('[OPTION]... DEST'))
 def archive(ui, repo, dest, **opts):
     '''create an unversioned archive of a repository revision
 
     By default, the revision used is the parent of the working
     directory; use -r/--rev to specify a different revision.
 
     The archive type is automatically detected based on file
     extension (to override, use -t/--type).
 
     .. container:: verbose
 
       Examples:
 
       - create a zip file containing the 1.0 release::
 
           hg archive -r 1.0 project-1.0.zip
 
       - create a tarball excluding .hg files::
 
           hg archive project.tar.gz -X ".hg*"
 
     Valid types are:
 
     :``files``: a directory full of files (default)
     :``tar``:   tar archive, uncompressed
     :``tbz2``:  tar archive, compressed using bzip2
     :``tgz``:   tar archive, compressed using gzip
     :``uzip``:  zip archive, uncompressed
     :``zip``:   zip archive, compressed using deflate
 
     The exact name of the destination archive or directory is given
     using a format string; see :hg:`help export` for details.
 
     Each member added to an archive file has a directory prefix
     prepended. Use -p/--prefix to specify a format string for the
     prefix. The default is the basename of the archive, with suffixes
     removed.
 
     Returns 0 on success.
     '''
 
     ctx = scmutil.revsingle(repo, opts.get('rev'))
     if not ctx:
         raise error.Abort(_('no working directory: please specify a revision'))
     node = ctx.node()
     dest = cmdutil.makefilename(repo, dest, node)
     if os.path.realpath(dest) == repo.root:
         raise error.Abort(_('repository root cannot be destination'))
 
     kind = opts.get('type') or archival.guesskind(dest) or 'files'
     prefix = opts.get('prefix')
 
     if dest == '-':
         if kind == 'files':
             raise error.Abort(_('cannot archive plain files to stdout'))
         dest = cmdutil.makefileobj(repo, dest)
         if not prefix:
             prefix = os.path.basename(repo.root) + '-%h'
 
     prefix = cmdutil.makefilename(repo, prefix, node)
     matchfn = scmutil.match(ctx, [], opts)
     archival.archive(repo, dest, node, kind, not opts.get('no_decode'),
                      matchfn, prefix, subrepos=opts.get('subrepos'))
 
 @command('backout',
     [('', 'merge', None, _('merge with old dirstate parent after backout')),
     ('', 'commit', None,
      _('commit if no conflicts were encountered (DEPRECATED)')),
     ('', 'no-commit', None, _('do not commit')),
     ('', 'parent', '',
      _('parent to choose when backing out merge (DEPRECATED)'), _('REV')),
     ('r', 'rev', '', _('revision to backout'), _('REV')),
     ('e', 'edit', False, _('invoke editor on commit messages')),
     ] + mergetoolopts + walkopts + commitopts + commitopts2,
     _('[OPTION]... [-r] REV'))
 def backout(ui, repo, node=None, rev=None, **opts):
     '''reverse effect of earlier changeset
 
     Prepare a new changeset with the effect of REV undone in the
     current working directory. If no conflicts were encountered,
     it will be committed immediately.
 
     If REV is the parent of the working directory, then this new changeset
     is committed automatically (unless --no-commit is specified).
 
     .. note::
 
        :hg:`backout` cannot be used to fix either an unwanted or
        incorrect merge.
 
     .. container:: verbose
 
       Examples:
 
       - Reverse the effect of the parent of the working directory.
         This backout will be committed immediately::
 
           hg backout -r .
 
       - Reverse the effect of previous bad revision 23::
 
           hg backout -r 23
 
       - Reverse the effect of previous bad revision 23 and
         leave changes uncommitted::
 
           hg backout -r 23 --no-commit
           hg commit -m "Backout revision 23"
 
       By default, the pending changeset will have one parent,
       maintaining a linear history. With --merge, the pending
       changeset will instead have two parents: the old parent of the
       working directory and a new child of REV that simply undoes REV.
 
       Before version 1.7, the behavior without --merge was equivalent
       to specifying --merge followed by :hg:`update --clean .` to
       cancel the merge and leave the child of REV as a head to be
       merged separately.
 
     See :hg:`help dates` for a list of formats valid for -d/--date.
 
     See :hg:`help revert` for a way to restore files to the state
     of another revision.
 
     Returns 0 on success, 1 if nothing to backout or there are unresolved
     files.
     '''
     wlock = lock = None
     try:
         wlock = repo.wlock()
         lock = repo.lock()
         return _dobackout(ui, repo, node, rev, **opts)
     finally:
         release(lock, wlock)
 
 def _dobackout(ui, repo, node=None, rev=None, **opts):
     if opts.get('commit') and opts.get('no_commit'):
         raise error.Abort(_("cannot use --commit with --no-commit"))
     if opts.get('merge') and opts.get('no_commit'):
         raise error.Abort(_("cannot use --merge with --no-commit"))
 
     if rev and node:
         raise error.Abort(_("please specify just one revision"))
 
     if not rev:
         rev = node
 
     if not rev:
         raise error.Abort(_("please specify a revision to backout"))
 
     date = opts.get('date')
     if date:
         opts['date'] = util.parsedate(date)
 
     cmdutil.checkunfinished(repo)
     cmdutil.bailifchanged(repo)
     node = scmutil.revsingle(repo, rev).node()
 
     op1, op2 = repo.dirstate.parents()
     if not repo.changelog.isancestor(node, op1):
         raise error.Abort(_('cannot backout change that is not an ancestor'))
 
     p1, p2 = repo.changelog.parents(node)
     if p1 == nullid:
         raise error.Abort(_('cannot backout a change with no parents'))
     if p2 != nullid:
         if not opts.get('parent'):
             raise error.Abort(_('cannot backout a merge changeset'))
         p = repo.lookup(opts['parent'])
         if p not in (p1, p2):
             raise error.Abort(_('%s is not a parent of %s') %
                              (short(p), short(node)))
         parent = p
     else:
         if opts.get('parent'):
             raise error.Abort(_('cannot use --parent on non-merge changeset'))
         parent = p1
 
     # the backout should appear on the same branch
     branch = repo.dirstate.branch()
     bheads = repo.branchheads(branch)
     rctx = scmutil.revsingle(repo, hex(parent))
     if not opts.get('merge') and op1 != node:
         dsguard = dirstateguard.dirstateguard(repo, 'backout')
         try:
             ui.setconfig('ui', 'forcemerge', opts.get('tool', ''),
                          'backout')
             stats = mergemod.update(repo, parent, True, True, node, False)
             repo.setparents(op1, op2)
             dsguard.close()
             hg._showstats(repo, stats)
             if stats[3]:
                 repo.ui.status(_("use 'hg resolve' to retry unresolved "
                                  "file merges\n"))
                 return 1
         finally:
             ui.setconfig('ui', 'forcemerge', '', '')
             lockmod.release(dsguard)
     else:
         hg.clean(repo, node, show_stats=False)
         repo.dirstate.setbranch(branch)
         cmdutil.revert(ui, repo, rctx, repo.dirstate.parents())
 
     if opts.get('no_commit'):
         msg = _("changeset %s backed out, "
                 "don't forget to commit.\n")
         ui.status(msg % short(node))
         return 0
 
     def commitfunc(ui, repo, message, match, opts):
         editform = 'backout'
         e = cmdutil.getcommiteditor(editform=editform, **opts)
         if not message:
             # we don't translate commit messages
             message = "Backed out changeset %s" % short(node)
             e = cmdutil.getcommiteditor(edit=True, editform=editform)
         return repo.commit(message, opts.get('user'), opts.get('date'),
                            match, editor=e)
     newnode = cmdutil.commit(ui, repo, commitfunc, [], opts)
     if not newnode:
         ui.status(_("nothing changed\n"))
         return 1
     cmdutil.commitstatus(repo, newnode, branch, bheads)
 
     def nice(node):
         return '%d:%s' % (repo.changelog.rev(node), short(node))
     ui.status(_('changeset %s backs out changeset %s\n') %
               (nice(repo.changelog.tip()), nice(node)))
     if opts.get('merge') and op1 != node:
         hg.clean(repo, op1, show_stats=False)
         ui.status(_('merging with changeset %s\n')
                   % nice(repo.changelog.tip()))
         try:
             ui.setconfig('ui', 'forcemerge', opts.get('tool', ''),
                          'backout')
             return hg.merge(repo, hex(repo.changelog.tip()))
         finally:
             ui.setconfig('ui', 'forcemerge', '', '')
     return 0
 
 @command('bisect',
     [('r', 'reset', False, _('reset bisect state')),
     ('g', 'good', False, _('mark changeset good')),
     ('b', 'bad', False, _('mark changeset bad')),
     ('s', 'skip', False, _('skip testing changeset')),
     ('e', 'extend', False, _('extend the bisect range')),
     ('c', 'command', '', _('use command to check changeset state'), _('CMD')),
     ('U', 'noupdate', False, _('do not update to target'))],
     _("[-gbsr] [-U] [-c CMD] [REV]"))
 def bisect(ui, repo, rev=None, extra=None, command=None,
                reset=None, good=None, bad=None, skip=None, extend=None,
                noupdate=None):
     """subdivision search of changesets
 
     This command helps to find changesets which introduce problems. To
     use, mark the earliest changeset you know exhibits the problem as
     bad, then mark the latest changeset which is free from the problem
     as good. Bisect will update your working directory to a revision
     for testing (unless the -U/--noupdate option is specified). Once
     you have performed tests, mark the working directory as good or
     bad, and bisect will either update to another candidate changeset
     or announce that it has found the bad revision.
 
     As a shortcut, you can also use the revision argument to mark a
     revision as good or bad without checking it out first.
 
     If you supply a command, it will be used for automatic bisection.
     The environment variable HG_NODE will contain the ID of the
     changeset being tested. The exit status of the command will be
     used to mark revisions as good or bad: status 0 means good, 125
     means to skip the revision, 127 (command not found) will abort the
     bisection, and any other non-zero exit status means the revision
     is bad.
 
     .. container:: verbose
 
       Some examples:
 
       - start a bisection with known bad revision 34, and good revision 12::
 
           hg bisect --bad 34
           hg bisect --good 12
 
       - advance the current bisection by marking current revision as good or
         bad::
 
           hg bisect --good
           hg bisect --bad
 
       - mark the current revision, or a known revision, to be skipped (e.g. if
         that revision is not usable because of another issue)::
 
           hg bisect --skip
           hg bisect --skip 23
 
       - skip all revisions that do not touch directories ``foo`` or ``bar``::
 
           hg bisect --skip "!( file('path:foo') & file('path:bar') )"
 
       - forget the current bisection::
 
           hg bisect --reset
 
       - use 'make && make tests' to automatically find the first broken
         revision::
 
           hg bisect --reset
           hg bisect --bad 34
           hg bisect --good 12
           hg bisect --command "make && make tests"
 
       - see all changesets whose states are already known in the current
         bisection::
 
           hg log -r "bisect(pruned)"
 
       - see the changeset currently being bisected (especially useful
         if running with -U/--noupdate)::
 
           hg log -r "bisect(current)"
 
       - see all changesets that took part in the current bisection::
 
           hg log -r "bisect(range)"
 
       - you can even get a nice graph::
 
           hg log --graph -r "bisect(range)"
 
       See :hg:`help revsets` for more about the `bisect()` keyword.
 
     Returns 0 on success.
     """
     # backward compatibility
     if rev in "good bad reset init".split():
         ui.warn(_("(use of 'hg bisect <cmd>' is deprecated)\n"))
         cmd, rev, extra = rev, extra, None
         if cmd == "good":
             good = True
         elif cmd == "bad":
             bad = True
         else:
             reset = True
     elif extra or good + bad + skip + reset + extend + bool(command) > 1:
         raise error.Abort(_('incompatible arguments'))
 
     cmdutil.checkunfinished(repo)
 
     if reset:
         hbisect.resetstate(repo)
         return
 
     state = hbisect.load_state(repo)
 
     # update state
     if good or bad or skip:
         if rev:
             nodes = [repo.lookup(i) for i in scmutil.revrange(repo, [rev])]
         else:
             nodes = [repo.lookup('.')]
         if good:
             state['good'] += nodes
         elif bad:
             state['bad'] += nodes
         elif skip:
             state['skip'] += nodes
         hbisect.save_state(repo, state)
         if not (state['good'] and state['bad']):
             return
 
     def mayupdate(repo, node, show_stats=True):
         """common used update sequence"""
         if noupdate:
             return
         cmdutil.bailifchanged(repo)
         return hg.clean(repo, node, show_stats=show_stats)
 
     displayer = cmdutil.show_changeset(ui, repo, {})
 
     if command:
         changesets = 1
         if noupdate:
             try:
                 node = state['current'][0]
             except LookupError:
                 raise error.Abort(_('current bisect revision is unknown - '
                                    'start a new bisect to fix'))
         else:
             node, p2 = repo.dirstate.parents()
             if p2 != nullid:
                 raise error.Abort(_('current bisect revision is a merge'))
         if rev:
             node = repo[scmutil.revsingle(repo, rev, node)].node()
         try:
             while changesets:
                 # update state
                 state['current'] = [node]
                 hbisect.save_state(repo, state)
                 status = ui.system(command, environ={'HG_NODE': hex(node)})
                 if status == 125:
                     transition = "skip"
                 elif status == 0:
                     transition = "good"
                 # status < 0 means process was killed
                 elif status == 127:
                     raise error.Abort(_("failed to execute %s") % command)
                 elif status < 0:
                     raise error.Abort(_("%s killed") % command)
                 else:
                     transition = "bad"
                 state[transition].append(node)
                 ctx = repo[node]
                 ui.status(_('changeset %d:%s: %s\n') % (ctx, ctx, transition))
                 hbisect.checkstate(state)
                 # bisect
                 nodes, changesets, bgood = hbisect.bisect(repo.changelog, state)
                 # update to next check
                 node = nodes[0]
                 mayupdate(repo, node, show_stats=False)
         finally:
             state['current'] = [node]
             hbisect.save_state(repo, state)
         hbisect.printresult(ui, repo, state, displayer, nodes, bgood)
         return
 
     hbisect.checkstate(state)
 
     # actually bisect
     nodes, changesets, good = hbisect.bisect(repo.changelog, state)
     if extend:
         if not changesets:
             extendnode = hbisect.extendrange(repo, state, nodes, good)
             if extendnode is not None:
                 ui.write(_("Extending search to changeset %d:%s\n")
                          % (extendnode.rev(), extendnode))
                 state['current'] = [extendnode.node()]
                 hbisect.save_state(repo, state)
                 return mayupdate(repo, extendnode.node())
         raise error.Abort(_("nothing to extend"))
 
     if changesets == 0:
         hbisect.printresult(ui, repo, state, displayer, nodes, good)
     else:
         assert len(nodes) == 1 # only a single node can be tested next
         node = nodes[0]
         # compute the approximate number of remaining tests
         tests, size = 0, 2
         while size <= changesets:
             tests, size = tests + 1, size * 2
         rev = repo.changelog.rev(node)
         ui.write(_("Testing changeset %d:%s "
                    "(%d changesets remaining, ~%d tests)\n")
                  % (rev, short(node), changesets, tests))
         state['current'] = [node]
         hbisect.save_state(repo, state)
         return mayupdate(repo, node)
 
 @command('bookmarks|bookmark',
     [('f', 'force', False, _('force')),
     ('r', 'rev', '', _('revision for bookmark action'), _('REV')),
     ('d', 'delete', False, _('delete a given bookmark')),
     ('m', 'rename', '', _('rename a given bookmark'), _('OLD')),
     ('i', 'inactive', False, _('mark a bookmark inactive')),
     ] + formatteropts,
     _('hg bookmarks [OPTIONS]... [NAME]...'))
 def bookmark(ui, repo, *names, **opts):
     '''create a new bookmark or list existing bookmarks
 
     Bookmarks are labels on changesets to help track lines of development.
     Bookmarks are unversioned and can be moved, renamed and deleted.
     Deleting or moving a bookmark has no effect on the associated changesets.
 
     Creating or updating to a bookmark causes it to be marked as 'active'.
     The active bookmark is indicated with a '*'.
     When a commit is made, the active bookmark will advance to the new commit.
     A plain :hg:`update` will also advance an active bookmark, if possible.
     Updating away from a bookmark will cause it to be deactivated.
 
     Bookmarks can be pushed and pulled between repositories (see
     :hg:`help push` and :hg:`help pull`). If a shared bookmark has
     diverged, a new 'divergent bookmark' of the form 'name@path' will
     be created. Using :hg:`merge` will resolve the divergence.
 
     A bookmark named '@' has the special property that :hg:`clone` will
     check it out by default if it exists.
 
     .. container:: verbose
 
       Examples:
 
       - create an active bookmark for a new line of development::
 
           hg book new-feature
 
       - create an inactive bookmark as a place marker::
 
           hg book -i reviewed
 
       - create an inactive bookmark on another changeset::
 
           hg book -r .^ tested
 
       - rename bookmark turkey to dinner::
 
           hg book -m turkey dinner
 
       - move the '@' bookmark from another branch::
 
           hg book -f @
     '''
     force = opts.get('force')
     rev = opts.get('rev')
     delete = opts.get('delete')
     rename = opts.get('rename')
     inactive = opts.get('inactive')
 
     def checkformat(mark):
         mark = mark.strip()
         if not mark:
             raise error.Abort(_("bookmark names cannot consist entirely of "
                                "whitespace"))
         scmutil.checknewlabel(repo, mark, 'bookmark')
         return mark
 
     def checkconflict(repo, mark, cur, force=False, target=None):
         if mark in marks and not force:
             if target:
                 if marks[mark] == target and target == cur:
                     # re-activating a bookmark
                     return
                 anc = repo.changelog.ancestors([repo[target].rev()])
                 bmctx = repo[marks[mark]]
                 divs = [repo[b].node() for b in marks
                         if b.split('@', 1)[0] == mark.split('@', 1)[0]]
 
                 # allow resolving a single divergent bookmark even if moving
                 # the bookmark across branches when a revision is specified
                 # that contains a divergent bookmark
                 if bmctx.rev() not in anc and target in divs:
                     bookmarks.deletedivergent(repo, [target], mark)
                     return
 
                 deletefrom = [b for b in divs
                               if repo[b].rev() in anc or b == target]
                 bookmarks.deletedivergent(repo, deletefrom, mark)
                 if bookmarks.validdest(repo, bmctx, repo[target]):
                     ui.status(_("moving bookmark '%s' forward from %s\n") %
                               (mark, short(bmctx.node())))
                     return
             raise error.Abort(_("bookmark '%s' already exists "
                                "(use -f to force)") % mark)
         if ((mark in repo.branchmap() or mark == repo.dirstate.branch())
             and not force):
             raise error.Abort(
                 _("a bookmark cannot have the name of an existing branch"))
 
     if delete and rename:
         raise error.Abort(_("--delete and --rename are incompatible"))
     if delete and rev:
         raise error.Abort(_("--rev is incompatible with --delete"))
     if rename and rev:
         raise error.Abort(_("--rev is incompatible with --rename"))
     if not names and (delete or rev):
         raise error.Abort(_("bookmark name required"))
 
     if delete or rename or names or inactive:
         wlock = lock = tr = None
         try:
             wlock = repo.wlock()
             lock = repo.lock()
             cur = repo.changectx('.').node()
             marks = repo._bookmarks
             if delete:
                 tr = repo.transaction('bookmark')
                 for mark in names:
                     if mark not in marks:
                         raise error.Abort(_("bookmark '%s' does not exist") %
                                          mark)
                     if mark == repo._activebookmark:
                         bookmarks.deactivate(repo)
                     del marks[mark]
 
             elif rename:
                 tr = repo.transaction('bookmark')
                 if not names:
                     raise error.Abort(_("new bookmark name required"))
                 elif len(names) > 1:
                     raise error.Abort(_("only one new bookmark name allowed"))
                 mark = checkformat(names[0])
                 if rename not in marks:
                     raise error.Abort(_("bookmark '%s' does not exist")
                                       % rename)
                 checkconflict(repo, mark, cur, force)
                 marks[mark] = marks[rename]
                 if repo._activebookmark == rename and not inactive:
                     bookmarks.activate(repo, mark)
                 del marks[rename]
             elif names:
                 tr = repo.transaction('bookmark')
                 newact = None
                 for mark in names:
                     mark = checkformat(mark)
                     if newact is None:
                         newact = mark
                     if inactive and mark == repo._activebookmark:
                         bookmarks.deactivate(repo)
                         return
                     tgt = cur
                     if rev:
                         tgt = scmutil.revsingle(repo, rev).node()
                     checkconflict(repo, mark, cur, force, tgt)
                     marks[mark] = tgt
                 if not inactive and cur == marks[newact] and not rev:
                     bookmarks.activate(repo, newact)
                 elif cur != tgt and newact == repo._activebookmark:
                     bookmarks.deactivate(repo)
             elif inactive:
                 if len(marks) == 0:
                     ui.status(_("no bookmarks set\n"))
                 elif not repo._activebookmark:
                     ui.status(_("no active bookmark\n"))
                 else:
                     bookmarks.deactivate(repo)
             if tr is not None:
                 marks.recordchange(tr)
                 tr.close()
         finally:
             lockmod.release(tr, lock, wlock)
     else: # show bookmarks
         fm = ui.formatter('bookmarks', opts)
         hexfn = fm.hexfunc
         marks = repo._bookmarks
         if len(marks) == 0 and fm.isplain():
             ui.status(_("no bookmarks set\n"))
         for bmark, n in sorted(marks.iteritems()):
             active = repo._activebookmark
             if bmark == active:
                 prefix, label = '*', activebookmarklabel
             else:
                 prefix, label = ' ', ''
 
             fm.startitem()
             if not ui.quiet:
                 fm.plain(' %s ' % prefix, label=label)
             fm.write('bookmark', '%s', bmark, label=label)
             pad = " " * (25 - encoding.colwidth(bmark))
             fm.condwrite(not ui.quiet, 'rev node', pad + ' %d:%s',
                          repo.changelog.rev(n), hexfn(n), label=label)
             fm.data(active=(bmark == active))
             fm.plain('\n')
         fm.end()
 
 @command('branch',
     [('f', 'force', None,
      _('set branch name even if it shadows an existing branch')),
     ('C', 'clean', None, _('reset branch name to parent branch name'))],
     _('[-fC] [NAME]'))
 def branch(ui, repo, label=None, **opts):
     """set or show the current branch name
 
     .. note::
 
        Branch names are permanent and global. Use :hg:`bookmark` to create a
        light-weight bookmark instead. See :hg:`help glossary` for more
        information about named branches and bookmarks.
 
     With no argument, show the current branch name. With one argument,
     set the working directory branch name (the branch will not exist
     in the repository until the next commit). Standard practice
     recommends that primary development take place on the 'default'
     branch.
 
     Unless -f/--force is specified, branch will not let you set a
     branch name that already exists.
 
     Use -C/--clean to reset the working directory branch to that of
     the parent of the working directory, negating a previous branch
     change.
 
     Use the command :hg:`update` to switch to an existing branch. Use
     :hg:`commit --close-branch` to mark this branch head as closed.
     When all heads of a branch are closed, the branch will be
     considered closed.
 
     Returns 0 on success.
     """
     if label:
         label = label.strip()
 
     if not opts.get('clean') and not label:
         ui.write("%s\n" % repo.dirstate.branch())
         return
 
     with repo.wlock():
         if opts.get('clean'):
             label = repo[None].p1().branch()
             repo.dirstate.setbranch(label)
             ui.status(_('reset working directory to branch %s\n') % label)
         elif label:
             if not opts.get('force') and label in repo.branchmap():
                 if label not in [p.branch() for p in repo[None].parents()]:
                     raise error.Abort(_('a branch of the same name already'
                                        ' exists'),
                                      # i18n: "it" refers to an existing branch
                                      hint=_("use 'hg update' to switch to it"))
             scmutil.checknewlabel(repo, label, 'branch')
             repo.dirstate.setbranch(label)
             ui.status(_('marked working directory as branch %s\n') % label)
 
             # find any open named branches aside from default
             others = [n for n, h, t, c in repo.branchmap().iterbranches()
                       if n != "default" and not c]
             if not others:
                 ui.status(_('(branches are permanent and global, '
                             'did you want a bookmark?)\n'))
 
 @command('branches',
     [('a', 'active', False,
       _('show only branches that have unmerged heads (DEPRECATED)')),
      ('c', 'closed', False, _('show normal and closed branches')),
     ] + formatteropts,
     _('[-c]'))
 def branches(ui, repo, active=False, closed=False, **opts):
     """list repository named branches
 
     List the repository's named branches, indicating which ones are
     inactive. If -c/--closed is specified, also list branches which have
     been marked closed (see :hg:`commit --close-branch`).
 
     Use the command :hg:`update` to switch to an existing branch.
 
     Returns 0.
     """
 
     fm = ui.formatter('branches', opts)
     hexfunc = fm.hexfunc
 
     allheads = set(repo.heads())
     branches = []
     for tag, heads, tip, isclosed in repo.branchmap().iterbranches():
         isactive = not isclosed and bool(set(heads) & allheads)
         branches.append((tag, repo[tip], isactive, not isclosed))
     branches.sort(key=lambda i: (i[2], i[1].rev(), i[0], i[3]),
                   reverse=True)
 
     for tag, ctx, isactive, isopen in branches:
         if active and not isactive:
             continue
         if isactive:
             label = 'branches.active'
             notice = ''
         elif not isopen:
             if not closed:
                 continue
             label = 'branches.closed'
             notice = _(' (closed)')
         else:
             label = 'branches.inactive'
             notice = _(' (inactive)')
         current = (tag == repo.dirstate.branch())
         if current:
             label = 'branches.current'
 
         fm.startitem()
         fm.write('branch', '%s', tag, label=label)
         rev = ctx.rev()
         padsize = max(31 - len(str(rev)) - encoding.colwidth(tag), 0)
         fmt = ' ' * padsize + ' %d:%s'
         fm.condwrite(not ui.quiet, 'rev node', fmt, rev, hexfunc(ctx.node()),
                      label='log.changeset changeset.%s' % ctx.phasestr())
         fm.data(active=isactive, closed=not isopen, current=current)
         if not ui.quiet:
             fm.plain(notice)
         fm.plain('\n')
     fm.end()
 
 @command('bundle',
     [('f', 'force', None, _('run even when the destination is unrelated')),
     ('r', 'rev', [], _('a changeset intended to be added to the destination'),
      _('REV')),
     ('b', 'branch', [], _('a specific branch you would like to bundle'),
      _('BRANCH')),
     ('', 'base', [],
      _('a base changeset assumed to be available at the destination'),
      _('REV')),
     ('a', 'all', None, _('bundle all changesets in the repository')),
     ('t', 'type', 'bzip2', _('bundle compression type to use'), _('TYPE')),
     ] + remoteopts,
     _('[-f] [-t TYPE] [-a] [-r REV]... [--base REV]... FILE [DEST]'))
 def bundle(ui, repo, fname, dest=None, **opts):
     """create a changegroup file
 
     Generate a changegroup file collecting changesets to be added
     to a repository.
 
     To create a bundle containing all changesets, use -a/--all
     (or --base null). Otherwise, hg assumes the destination will have
     all the nodes you specify with --base parameters. Otherwise, hg
     will assume the repository has all the nodes in destination, or
     default-push/default if no destination is specified.
 
     You can change bundle format with the -t/--type option. You can
     specify a compression, a bundle version or both using a dash
     (comp-version). The available compression methods are: none, bzip2,
     and gzip (by default, bundles are compressed using bzip2). The
     available formats are: v1, v2 (default to most suitable).
 
     The bundle file can then be transferred using conventional means
     and applied to another repository with the unbundle or pull
     command. This is useful when direct push and pull are not
     available or when exporting an entire repository is undesirable.
 
     Applying bundles preserves all changeset contents including
     permissions, copy/rename information, and revision history.
 
     Returns 0 on success, 1 if no changes found.
     """
     revs = None
     if 'rev' in opts:
         revstrings = opts['rev']
         revs = scmutil.revrange(repo, revstrings)
         if revstrings and not revs:
             raise error.Abort(_('no commits to bundle'))
 
     bundletype = opts.get('type', 'bzip2').lower()
     try:
         bcompression, cgversion, params = exchange.parsebundlespec(
                 repo, bundletype, strict=False)
     except error.UnsupportedBundleSpecification as e:
         raise error.Abort(str(e),
                           hint=_("see 'hg help bundle' for supported "
                                  "values for --type"))
 
     # Packed bundles are a pseudo bundle format for now.
     if cgversion == 's1':
         raise error.Abort(_('packed bundles cannot be produced by "hg bundle"'),
                           hint=_("use 'hg debugcreatestreamclonebundle'"))
 
     if opts.get('all'):
         if dest:
             raise error.Abort(_("--all is incompatible with specifying "
                                 "a destination"))
         if opts.get('base'):
             ui.warn(_("ignoring --base because --all was specified\n"))
         base = ['null']
     else:
         base = scmutil.revrange(repo, opts.get('base'))
     # TODO: get desired bundlecaps from command line.
     bundlecaps = None
     if cgversion not in changegroup.supportedoutgoingversions(repo):
         raise error.Abort(_("repository does not support bundle version %s") %
                           cgversion)
 
     if base:
         if dest:
             raise error.Abort(_("--base is incompatible with specifying "
                                "a destination"))
         common = [repo.lookup(rev) for rev in base]
         heads = revs and map(repo.lookup, revs) or None
         outgoing = discovery.outgoing(repo, common, heads)
         cg = changegroup.getchangegroup(repo, 'bundle', outgoing,
                                         bundlecaps=bundlecaps,
                                         version=cgversion)
         outgoing = None
     else:
         dest = ui.expandpath(dest or 'default-push', dest or 'default')
         dest, branches = hg.parseurl(dest, opts.get('branch'))
         other = hg.peer(repo, opts, dest)
         revs, checkout = hg.addbranchrevs(repo, repo, branches, revs)
         heads = revs and map(repo.lookup, revs) or revs
         outgoing = discovery.findcommonoutgoing(repo, other,
                                                 onlyheads=heads,
                                                 force=opts.get('force'),
                                                 portable=True)
         cg = changegroup.getlocalchangegroup(repo, 'bundle', outgoing,
                                                 bundlecaps, version=cgversion)
     if not cg:
         scmutil.nochangesfound(ui, repo, outgoing and outgoing.excluded)
         return 1
 
     if cgversion == '01': #bundle1
         if bcompression is None:
             bcompression = 'UN'
         bversion = 'HG10' + bcompression
         bcompression = None
     else:
         assert cgversion == '02'
         bversion = 'HG20'
 
     bundle2.writebundle(ui, cg, fname, bversion, compression=bcompression)
 
 @command('cat',
     [('o', 'output', '',
      _('print output to file with formatted name'), _('FORMAT')),
     ('r', 'rev', '', _('print the given revision'), _('REV')),
     ('', 'decode', None, _('apply any matching decode filter')),
     ] + walkopts,
     _('[OPTION]... FILE...'),
     inferrepo=True)
 def cat(ui, repo, file1, *pats, **opts):
     """output the current or given revision of files
 
     Print the specified files as they were at the given revision. If
     no revision is given, the parent of the working directory is used.
 
     Output may be to a file, in which case the name of the file is
     given using a format string. The formatting rules as follows:
 
     :``%%``: literal "%" character
     :``%s``: basename of file being printed
     :``%d``: dirname of file being printed, or '.' if in repository root
     :``%p``: root-relative path name of file being printed
     :``%H``: changeset hash (40 hexadecimal digits)
     :``%R``: changeset revision number
     :``%h``: short-form changeset hash (12 hexadecimal digits)
     :``%r``: zero-padded changeset revision number
     :``%b``: basename of the exporting repository
 
     Returns 0 on success.
     """
     ctx = scmutil.revsingle(repo, opts.get('rev'))
     m = scmutil.match(ctx, (file1,) + pats, opts)
 
     return cmdutil.cat(ui, repo, ctx, m, '', **opts)
 
 @command('^clone',
     [('U', 'noupdate', None, _('the clone will include an empty working '
                                'directory (only a repository)')),
     ('u', 'updaterev', '', _('revision, tag, or branch to check out'),
         _('REV')),
     ('r', 'rev', [], _('include the specified changeset'), _('REV')),
     ('b', 'branch', [], _('clone only the specified branch'), _('BRANCH')),
     ('', 'pull', None, _('use pull protocol to copy metadata')),
     ('', 'uncompressed', None, _('use uncompressed transfer (fast over LAN)')),
     ] + remoteopts,
     _('[OPTION]... SOURCE [DEST]'),
     norepo=True)
 def clone(ui, source, dest=None, **opts):
     """make a copy of an existing repository
 
     Create a copy of an existing repository in a new directory.
 
     If no destination directory name is specified, it defaults to the
     basename of the source.
 
     The location of the source is added to the new repository's
     ``.hg/hgrc`` file, as the default to be used for future pulls.
 
     Only local paths and ``ssh://`` URLs are supported as
     destinations. For ``ssh://`` destinations, no working directory or
     ``.hg/hgrc`` will be created on the remote side.
 
     If the source repository has a bookmark called '@' set, that
     revision will be checked out in the new repository by default.
 
     To check out a particular version, use -u/--update, or
     -U/--noupdate to create a clone with no working directory.
 
     To pull only a subset of changesets, specify one or more revisions
     identifiers with -r/--rev or branches with -b/--branch. The
     resulting clone will contain only the specified changesets and
     their ancestors. These options (or 'clone src#rev dest') imply
     --pull, even for local source repositories.
 
     .. note::
 
        Specifying a tag will include the tagged changeset but not the
        changeset containing the tag.
 
     .. container:: verbose
 
       For efficiency, hardlinks are used for cloning whenever the
       source and destination are on the same filesystem (note this
       applies only to the repository data, not to the working
       directory). Some filesystems, such as AFS, implement hardlinking
       incorrectly, but do not report errors. In these cases, use the
       --pull option to avoid hardlinking.
 
       In some cases, you can clone repositories and the working
       directory using full hardlinks with ::
 
         $ cp -al REPO REPOCLONE
 
       This is the fastest way to clone, but it is not always safe. The
       operation is not atomic (making sure REPO is not modified during
       the operation is up to you) and you have to make sure your
       editor breaks hardlinks (Emacs and most Linux Kernel tools do
       so). Also, this is not compatible with certain extensions that
       place their metadata under the .hg directory, such as mq.
 
       Mercurial will update the working directory to the first applicable
       revision from this list:
 
       a) null if -U or the source repository has no changesets
       b) if -u . and the source repository is local, the first parent of
          the source repository's working directory
       c) the changeset specified with -u (if a branch name, this means the
          latest head of that branch)
       d) the changeset specified with -r
       e) the tipmost head specified with -b
       f) the tipmost head specified with the url#branch source syntax
       g) the revision marked with the '@' bookmark, if present
       h) the tipmost head of the default branch
       i) tip
 
       When cloning from servers that support it, Mercurial may fetch
       pre-generated data from a server-advertised URL. When this is done,
       hooks operating on incoming changesets and changegroups may fire twice,
       once for the bundle fetched from the URL and another for any additional
       data not fetched from this URL. In addition, if an error occurs, the
       repository may be rolled back to a partial clone. This behavior may
       change in future releases. See :hg:`help -e clonebundles` for more.
 
       Examples:
 
       - clone a remote repository to a new directory named hg/::
 
           hg clone https://www.mercurial-scm.org/repo/hg/
 
       - create a lightweight local clone::
 
           hg clone project/ project-feature/
 
       - clone from an absolute path on an ssh server (note double-slash)::
 
           hg clone ssh://user@server//home/projects/alpha/
 
       - do a high-speed clone over a LAN while checking out a
         specified version::
 
           hg clone --uncompressed http://server/repo -u 1.5
 
       - create a repository without changesets after a particular revision::
 
           hg clone -r 04e544 experimental/ good/
 
       - clone (and track) a particular named branch::
 
           hg clone https://www.mercurial-scm.org/repo/hg/#stable
 
     See :hg:`help urls` for details on specifying URLs.
 
     Returns 0 on success.
     """
     if opts.get('noupdate') and opts.get('updaterev'):
         raise error.Abort(_("cannot specify both --noupdate and --updaterev"))
 
     r = hg.clone(ui, opts, source, dest,
                  pull=opts.get('pull'),
                  stream=opts.get('uncompressed'),
                  rev=opts.get('rev'),
                  update=opts.get('updaterev') or not opts.get('noupdate'),
                  branch=opts.get('branch'),
                  shareopts=opts.get('shareopts'))
 
     return r is None
 
 @command('^commit|ci',
     [('A', 'addremove', None,
      _('mark new/missing files as added/removed before committing')),
     ('', 'close-branch', None,
      _('mark a branch head as closed')),
     ('', 'amend', None, _('amend the parent of the working directory')),
     ('s', 'secret', None, _('use the secret phase for committing')),
     ('e', 'edit', None, _('invoke editor on commit messages')),
     ('i', 'interactive', None, _('use interactive mode')),
     ] + walkopts + commitopts + commitopts2 + subrepoopts,
     _('[OPTION]... [FILE]...'),
     inferrepo=True)
 def commit(ui, repo, *pats, **opts):
     """commit the specified files or all outstanding changes
 
     Commit changes to the given files into the repository. Unlike a
     centralized SCM, this operation is a local operation. See
     :hg:`push` for a way to actively distribute your changes.
 
     If a list of files is omitted, all changes reported by :hg:`status`
     will be committed.
 
     If you are committing the result of a merge, do not provide any
     filenames or -I/-X filters.
 
     If no commit message is specified, Mercurial starts your
     configured editor where you can enter a message. In case your
     commit fails, you will find a backup of your message in
     ``.hg/last-message.txt``.
 
     The --close-branch flag can be used to mark the current branch
     head closed. When all heads of a branch are closed, the branch
     will be considered closed and no longer listed.
 
     The --amend flag can be used to amend the parent of the
     working directory with a new commit that contains the changes
     in the parent in addition to those currently reported by :hg:`status`,
     if there are any. The old commit is stored in a backup bundle in
     ``.hg/strip-backup`` (see :hg:`help bundle` and :hg:`help unbundle`
     on how to restore it).
 
     Message, user and date are taken from the amended commit unless
     specified. When a message isn't specified on the command line,
     the editor will open with the message of the amended commit.
 
     It is not possible to amend public changesets (see :hg:`help phases`)
     or changesets that have children.
 
     See :hg:`help dates` for a list of formats valid for -d/--date.
 
     Returns 0 on success, 1 if nothing changed.
 
     .. container:: verbose
 
       Examples:
 
       - commit all files ending in .py::
 
           hg commit --include "set:**.py"
 
       - commit all non-binary files::
 
           hg commit --exclude "set:binary()"
 
       - amend the current commit and set the date to now::
 
           hg commit --amend --date now
     """
     wlock = lock = None
     try:
         wlock = repo.wlock()
         lock = repo.lock()
         return _docommit(ui, repo, *pats, **opts)
     finally:
         release(lock, wlock)
 
 def _docommit(ui, repo, *pats, **opts):
     if opts.get('interactive'):
         opts.pop('interactive')
         ret = cmdutil.dorecord(ui, repo, commit, None, False,
                                cmdutil.recordfilter, *pats, **opts)
         # ret can be 0 (no changes to record) or the value returned by
         # commit(), 1 if nothing changed or None on success.
         return 1 if ret == 0 else ret
 
     if opts.get('subrepos'):
         if opts.get('amend'):
             raise error.Abort(_('cannot amend with --subrepos'))
         # Let --subrepos on the command line override config setting.
         ui.setconfig('ui', 'commitsubrepos', True, 'commit')
 
     cmdutil.checkunfinished(repo, commit=True)
 
     branch = repo[None].branch()
     bheads = repo.branchheads(branch)
 
     extra = {}
     if opts.get('close_branch'):
         extra['close'] = 1
 
         if not bheads:
             raise error.Abort(_('can only close branch heads'))
         elif opts.get('amend'):
             if repo[None].parents()[0].p1().branch() != branch and \
                     repo[None].parents()[0].p2().branch() != branch:
                 raise error.Abort(_('can only close branch heads'))
 
     if opts.get('amend'):
         if ui.configbool('ui', 'commitsubrepos'):
             raise error.Abort(_('cannot amend with ui.commitsubrepos enabled'))
 
         old = repo['.']
         if not old.mutable():
             raise error.Abort(_('cannot amend public changesets'))
         if len(repo[None].parents()) > 1:
             raise error.Abort(_('cannot amend while merging'))
         allowunstable = obsolete.isenabled(repo, obsolete.allowunstableopt)
         if not allowunstable and old.children():
             raise error.Abort(_('cannot amend changeset with children'))
 
         # Currently histedit gets confused if an amend happens while histedit
         # is in progress. Since we have a checkunfinished command, we are
         # temporarily honoring it.
         #
         # Note: eventually this guard will be removed. Please do not expect
         # this behavior to remain.
         if not obsolete.isenabled(repo, obsolete.createmarkersopt):
             cmdutil.checkunfinished(repo)
 
         # commitfunc is used only for temporary amend commit by cmdutil.amend
         def commitfunc(ui, repo, message, match, opts):
             return repo.commit(message,
                                opts.get('user') or old.user(),
                                opts.get('date') or old.date(),
                                match,
                                extra=extra)
 
         node = cmdutil.amend(ui, repo, commitfunc, old, extra, pats, opts)
         if node == old.node():
             ui.status(_("nothing changed\n"))
             return 1
     else:
         def commitfunc(ui, repo, message, match, opts):
             backup = ui.backupconfig('phases', 'new-commit')
             baseui = repo.baseui
             basebackup = baseui.backupconfig('phases', 'new-commit')
             try:
                 if opts.get('secret'):
                     ui.setconfig('phases', 'new-commit', 'secret', 'commit')
                     # Propagate to subrepos
                     baseui.setconfig('phases', 'new-commit', 'secret', 'commit')
 
                 editform = cmdutil.mergeeditform(repo[None], 'commit.normal')
                 editor = cmdutil.getcommiteditor(editform=editform, **opts)
                 return repo.commit(message, opts.get('user'), opts.get('date'),
                                    match,
                                    editor=editor,
                                    extra=extra)
             finally:
                 ui.restoreconfig(backup)
                 repo.baseui.restoreconfig(basebackup)
 
 
         node = cmdutil.commit(ui, repo, commitfunc, pats, opts)
 
         if not node:
             stat = cmdutil.postcommitstatus(repo, pats, opts)
             if stat[3]:
                 ui.status(_("nothing changed (%d missing files, see "
                             "'hg status')\n") % len(stat[3]))
             else:
                 ui.status(_("nothing changed\n"))
             return 1
 
     cmdutil.commitstatus(repo, node, branch, bheads, opts)
 
 @command('config|showconfig|debugconfig',
     [('u', 'untrusted', None, _('show untrusted configuration options')),
      ('e', 'edit', None, _('edit user config')),
      ('l', 'local', None, _('edit repository config')),
      ('g', 'global', None, _('edit global config'))] + formatteropts,
     _('[-u] [NAME]...'),
     optionalrepo=True)
 def config(ui, repo, *values, **opts):
     """show combined config settings from all hgrc files
 
     With no arguments, print names and values of all config items.
 
     With one argument of the form section.name, print just the value
     of that config item.
 
     With multiple arguments, print names and values of all config
     items with matching section names.
 
     With --edit, start an editor on the user-level config file. With
     --global, edit the system-wide config file. With --local, edit the
     repository-level config file.
 
     With --debug, the source (filename and line number) is printed
     for each config item.
 
     See :hg:`help config` for more information about config files.
 
     Returns 0 on success, 1 if NAME does not exist.
 
     """
 
     if opts.get('edit') or opts.get('local') or opts.get('global'):
         if opts.get('local') and opts.get('global'):
             raise error.Abort(_("can't use --local and --global together"))
 
         if opts.get('local'):
             if not repo:
                 raise error.Abort(_("can't use --local outside a repository"))
             paths = [repo.join('hgrc')]
         elif opts.get('global'):
             paths = scmutil.systemrcpath()
         else:
             paths = scmutil.userrcpath()
 
         for f in paths:
             if os.path.exists(f):
                 break
         else:
             if opts.get('global'):
                 samplehgrc = uimod.samplehgrcs['global']
             elif opts.get('local'):
                 samplehgrc = uimod.samplehgrcs['local']
             else:
                 samplehgrc = uimod.samplehgrcs['user']
 
             f = paths[0]
             fp = open(f, "w")
             fp.write(samplehgrc)
             fp.close()
 
         editor = ui.geteditor()
         ui.system("%s \"%s\"" % (editor, f),
                   onerr=error.Abort, errprefix=_("edit failed"))
         return
 
     fm = ui.formatter('config', opts)
     for f in scmutil.rcpath():
         ui.debug('read config from: %s\n' % f)
     untrusted = bool(opts.get('untrusted'))
     if values:
         sections = [v for v in values if '.' not in v]
         items = [v for v in values if '.' in v]
         if len(items) > 1 or items and sections:
             raise error.Abort(_('only one config item permitted'))
     matched = False
     for section, name, value in ui.walkconfig(untrusted=untrusted):
         source = ui.configsource(section, name, untrusted)
         value = str(value)
         if fm.isplain():
             source = source or 'none'
             value = value.replace('\n', '\\n')
         entryname = section + '.' + name
         if values:
             for v in values:
                 if v == section:
                     fm.startitem()
                     fm.condwrite(ui.debugflag, 'source', '%s: ', source)
                     fm.write('name value', '%s=%s\n', entryname, value)
                     matched = True
                 elif v == entryname:
                     fm.startitem()
                     fm.condwrite(ui.debugflag, 'source', '%s: ', source)
                     fm.write('value', '%s\n', value)
                     fm.data(name=entryname)
                     matched = True
         else:
             fm.startitem()
             fm.condwrite(ui.debugflag, 'source', '%s: ', source)
             fm.write('name value', '%s=%s\n', entryname, value)
             matched = True
     fm.end()
     if matched:
         return 0
     return 1
 
 @command('copy|cp',
     [('A', 'after', None, _('record a copy that has already occurred')),
     ('f', 'force', None, _('forcibly copy over an existing managed file')),
     ] + walkopts + dryrunopts,
     _('[OPTION]... [SOURCE]... DEST'))
 def copy(ui, repo, *pats, **opts):
     """mark files as copied for the next commit
 
     Mark dest as having copies of source files. If dest is a
     directory, copies are put in that directory. If dest is a file,
     the source must be a single file.
 
     By default, this command copies the contents of files as they
     exist in the working directory. If invoked with -A/--after, the
     operation is recorded, but no copying is performed.
 
     This command takes effect with the next commit. To undo a copy
     before that, see :hg:`revert`.
 
     Returns 0 on success, 1 if errors are encountered.
     """
     with repo.wlock(False):
         return cmdutil.copy(ui, repo, pats, opts)
 
 @command('debuginstall', [] + formatteropts, '', norepo=True)
 def debuginstall(ui, **opts):
     '''test Mercurial installation
 
     Returns 0 on success.
     '''
 
     def writetemp(contents):
         (fd, name) = tempfile.mkstemp(prefix="hg-debuginstall-")
         f = os.fdopen(fd, "wb")
         f.write(contents)
         f.close()
         return name
 
     problems = 0
 
     fm = ui.formatter('debuginstall', opts)
     fm.startitem()
 
     # encoding
     fm.write('encoding', _("checking encoding (%s)...\n"), encoding.encoding)
     err = None
     try:
         encoding.fromlocal("test")
     except error.Abort as inst:
         err = inst
         problems += 1
     fm.condwrite(err, 'encodingerror', _(" %s\n"
                  " (check that your locale is properly set)\n"), err)
 
     # Python
     fm.write('pythonexe', _("checking Python executable (%s)\n"),
-             sys.executable)
+             pycompat.sysexecutable)
     fm.write('pythonver', _("checking Python version (%s)\n"),
              ("%d.%d.%d" % sys.version_info[:3]))
     fm.write('pythonlib', _("checking Python lib (%s)...\n"),
              os.path.dirname(os.__file__))
 
     security = set(sslutil.supportedprotocols)
     if sslutil.hassni:
         security.add('sni')
 
     fm.write('pythonsecurity', _("checking Python security support (%s)\n"),
              fm.formatlist(sorted(security), name='protocol',
                            fmt='%s', sep=','))
 
     # These are warnings, not errors. So don't increment problem count. This
     # may change in the future.
     if 'tls1.2' not in security:
         fm.plain(_('  TLS 1.2 not supported by Python install; '
                    'network connections lack modern security\n'))
     if 'sni' not in security:
         fm.plain(_('  SNI not supported by Python install; may have '
                    'connectivity issues with some servers\n'))
 
     # TODO print CA cert info
 
     # hg version
     hgver = util.version()
     fm.write('hgver', _("checking Mercurial version (%s)\n"),
              hgver.split('+')[0])
     fm.write('hgverextra', _("checking Mercurial custom build (%s)\n"),
              '+'.join(hgver.split('+')[1:]))
 
     # compiled modules
     fm.write('hgmodulepolicy', _("checking module policy (%s)\n"),
              policy.policy)
     fm.write('hgmodules', _("checking installed modules (%s)...\n"),
              os.path.dirname(__file__))
 
     err = None
     try:
         from . import (
             base85,
             bdiff,
             mpatch,
             osutil,
         )
         dir(bdiff), dir(mpatch), dir(base85), dir(osutil) # quiet pyflakes
     except Exception as inst:
         err = inst
         problems += 1
     fm.condwrite(err, 'extensionserror', " %s\n", err)
 
     compengines = util.compengines._engines.values()
     fm.write('compengines', _('checking registered compression engines (%s)\n'),
              fm.formatlist(sorted(e.name() for e in compengines),
                            name='compengine', fmt='%s', sep=', '))
     fm.write('compenginesavail', _('checking available compression engines '
                                    '(%s)\n'),
              fm.formatlist(sorted(e.name() for e in compengines
                                   if e.available()),
                            name='compengine', fmt='%s', sep=', '))
 
     # templates
     p = templater.templatepaths()
     fm.write('templatedirs', 'checking templates (%s)...\n', ' '.join(p))
     fm.condwrite(not p, '', _(" no template directories found\n"))
     if p:
         m = templater.templatepath("map-cmdline.default")
         if m:
             # template found, check if it is working
             err = None
             try:
                 templater.templater.frommapfile(m)
             except Exception as inst:
                 err = inst
                 p = None
             fm.condwrite(err, 'defaulttemplateerror', " %s\n", err)
         else:
             p = None
         fm.condwrite(p, 'defaulttemplate',
                      _("checking default template (%s)\n"), m)
         fm.condwrite(not m, 'defaulttemplatenotfound',
                      _(" template '%s' not found\n"), "default")
     if not p:
         problems += 1
     fm.condwrite(not p, '',
                  _(" (templates seem to have been installed incorrectly)\n"))
 
     # editor
     editor = ui.geteditor()
     editor = util.expandpath(editor)
     fm.write('editor', _("checking commit editor... (%s)\n"), editor)
     cmdpath = util.findexe(shlex.split(editor)[0])
     fm.condwrite(not cmdpath and editor == 'vi', 'vinotfound',
                  _(" No commit editor set and can't find %s in PATH\n"
                    " (specify a commit editor in your configuration"
                    " file)\n"), not cmdpath and editor == 'vi' and editor)
     fm.condwrite(not cmdpath and editor != 'vi', 'editornotfound',
                  _(" Can't find editor '%s' in PATH\n"
                    " (specify a commit editor in your configuration"
                    " file)\n"), not cmdpath and editor)
     if not cmdpath and editor != 'vi':
         problems += 1
 
     # check username
     username = None
     err = None
     try:
         username = ui.username()
     except error.Abort as e:
         err = e
         problems += 1
 
     fm.condwrite(username, 'username',  _("checking username (%s)\n"), username)
     fm.condwrite(err, 'usernameerror', _("checking username...\n %s\n"
         " (specify a username in your configuration file)\n"), err)
 
     fm.condwrite(not problems, '',
                  _("no problems detected\n"))
     if not problems:
         fm.data(problems=problems)
     fm.condwrite(problems, 'problems',
                  _("%d problems detected,"
                    " please check your install!\n"), problems)
     fm.end()
 
     return problems
 
 @command('debugknown', [], _('REPO ID...'), norepo=True)
 def debugknown(ui, repopath, *ids, **opts):
     """test whether node ids are known to a repo
 
     Every ID must be a full-length hex node id string. Returns a list of 0s
     and 1s indicating unknown/known.
     """
     repo = hg.peer(ui, opts, repopath)
     if not repo.capable('known'):
         raise error.Abort("known() not supported by target repository")
     flags = repo.known([bin(s) for s in ids])
     ui.write("%s\n" % ("".join([f and "1" or "0" for f in flags])))
 
 @command('debuglabelcomplete', [], _('LABEL...'))
 def debuglabelcomplete(ui, repo, *args):
     '''backwards compatibility with old bash completion scripts (DEPRECATED)'''
     debugnamecomplete(ui, repo, *args)
 
 @command('debugmergestate', [], '')
 def debugmergestate(ui, repo, *args):
     """print merge state
 
     Use --verbose to print out information about whether v1 or v2 merge state
     was chosen."""
     def _hashornull(h):
         if h == nullhex:
             return 'null'
         else:
             return h
 
     def printrecords(version):
         ui.write(('* version %s records\n') % version)
         if version == 1:
             records = v1records
         else:
             records = v2records
 
         for rtype, record in records:
             # pretty print some record types
             if rtype == 'L':
                 ui.write(('local: %s\n') % record)
             elif rtype == 'O':
                 ui.write(('other: %s\n') % record)
             elif rtype == 'm':
                 driver, mdstate = record.split('\0', 1)
                 ui.write(('merge driver: %s (state "%s")\n')
                          % (driver, mdstate))
             elif rtype in 'FDC':
                 r = record.split('\0')
                 f, state, hash, lfile, afile, anode, ofile = r[0:7]
                 if version == 1:
                     onode = 'not stored in v1 format'
                     flags = r[7]
                 else:
                     onode, flags = r[7:9]
                 ui.write(('file: %s (record type "%s", state "%s", hash %s)\n')
                          % (f, rtype, state, _hashornull(hash)))
                 ui.write(('  local path: %s (flags "%s")\n') % (lfile, flags))
                 ui.write(('  ancestor path: %s (node %s)\n')
                          % (afile, _hashornull(anode)))
                 ui.write(('  other path: %s (node %s)\n')
                          % (ofile, _hashornull(onode)))
             elif rtype == 'f':
                 filename, rawextras = record.split('\0', 1)
                 extras = rawextras.split('\0')
                 i = 0
                 extrastrings = []
                 while i < len(extras):
                     extrastrings.append('%s = %s' % (extras[i], extras[i + 1]))
                     i += 2
 
                 ui.write(('file extras: %s (%s)\n')
                          % (filename, ', '.join(extrastrings)))
             elif rtype == 'l':
                 labels = record.split('\0', 2)
                 labels = [l for l in labels if len(l) > 0]
                 ui.write(('labels:\n'))
                 ui.write(('  local: %s\n' % labels[0]))
                 ui.write(('  other: %s\n' % labels[1]))
                 if len(labels) > 2:
                     ui.write(('  base:  %s\n' % labels[2]))
             else:
                 ui.write(('unrecognized entry: %s\t%s\n')
                          % (rtype, record.replace('\0', '\t')))
 
     # Avoid mergestate.read() since it may raise an exception for unsupported
     # merge state records. We shouldn't be doing this, but this is OK since this
     # command is pretty low-level.
     ms = mergemod.mergestate(repo)
 
     # sort so that reasonable information is on top
     v1records = ms._readrecordsv1()
     v2records = ms._readrecordsv2()
     order = 'LOml'
     def key(r):
         idx = order.find(r[0])
         if idx == -1:
             return (1, r[1])
         else:
             return (0, idx)
     v1records.sort(key=key)
     v2records.sort(key=key)
 
     if not v1records and not v2records:
         ui.write(('no merge state found\n'))
     elif not v2records:
         ui.note(('no version 2 merge state\n'))
         printrecords(1)
     elif ms._v1v2match(v1records, v2records):
         ui.note(('v1 and v2 states match: using v2\n'))
         printrecords(2)
     else:
         ui.note(('v1 and v2 states mismatch: using v1\n'))
         printrecords(1)
         if ui.verbose:
             printrecords(2)
 
 @command('debugnamecomplete', [], _('NAME...'))
 def debugnamecomplete(ui, repo, *args):
     '''complete "names" - tags, open branch names, bookmark names'''
 
     names = set()
     # since we previously only listed open branches, we will handle that
     # specially (after this for loop)
     for name, ns in repo.names.iteritems():
         if name != 'branches':
             names.update(ns.listnames(repo))
     names.update(tag for (tag, heads, tip, closed)
                  in repo.branchmap().iterbranches() if not closed)
     completions = set()
     if not args:
         args = ['']
     for a in args:
         completions.update(n for n in names if n.startswith(a))
     ui.write('\n'.join(sorted(completions)))
     ui.write('\n')
 
 @command('debuglocks',
          [('L', 'force-lock', None, _('free the store lock (DANGEROUS)')),
           ('W', 'force-wlock', None,
            _('free the working state lock (DANGEROUS)'))],
          _('[OPTION]...'))
 def debuglocks(ui, repo, **opts):
     """show or modify state of locks
 
     By default, this command will show which locks are held. This
     includes the user and process holding the lock, the amount of time
     the lock has been held, and the machine name where the process is
     running if it's not local.
 
     Locks protect the integrity of Mercurial's data, so should be
     treated with care. System crashes or other interruptions may cause
     locks to not be properly released, though Mercurial will usually
     detect and remove such stale locks automatically.
 
     However, detecting stale locks may not always be possible (for
     instance, on a shared filesystem). Removing locks may also be
     blocked by filesystem permissions.
 
     Returns 0 if no locks are held.
 
     """
 
     if opts.get('force_lock'):
         repo.svfs.unlink('lock')
     if opts.get('force_wlock'):
         repo.vfs.unlink('wlock')
     if opts.get('force_lock') or opts.get('force_lock'):
         return 0
 
     now = time.time()
     held = 0
 
     def report(vfs, name, method):
         # this causes stale locks to get reaped for more accurate reporting
         try:
             l = method(False)
         except error.LockHeld:
             l = None
 
         if l:
             l.release()
         else:
             try:
                 stat = vfs.lstat(name)
                 age = now - stat.st_mtime
                 user = util.username(stat.st_uid)
                 locker = vfs.readlock(name)
                 if ":" in locker:
                     host, pid = locker.split(':')
                     if host == socket.gethostname():
                         locker = 'user %s, process %s' % (user, pid)
                     else:
                         locker = 'user %s, process %s, host %s' \
                                  % (user, pid, host)
                 ui.write(("%-6s %s (%ds)\n") % (name + ":", locker, age))
                 return 1
             except OSError as e:
                 if e.errno != errno.ENOENT:
                     raise
 
         ui.write(("%-6s free\n") % (name + ":"))
         return 0
 
     held += report(repo.svfs, "lock", repo.lock)
     held += report(repo.vfs, "wlock", repo.wlock)
 
     return held
 
 @command('debugobsolete',
         [('', 'flags', 0, _('markers flag')),
          ('', 'record-parents', False,
           _('record parent information for the precursor')),
          ('r', 'rev', [], _('display markers relevant to REV')),
          ('', 'index', False, _('display index of the marker')),
          ('', 'delete', [], _('delete markers specified by indices')),
         ] + commitopts2 + formatteropts,
          _('[OBSOLETED [REPLACEMENT ...]]'))
 def debugobsolete(ui, repo, precursor=None, *successors, **opts):
     """create arbitrary obsolete marker
 
     With no arguments, displays the list of obsolescence markers."""
 
     def parsenodeid(s):
         try:
             # We do not use revsingle/revrange functions here to accept
             # arbitrary node identifiers, possibly not present in the
             # local repository.
             n = bin(s)
             if len(n) != len(nullid):
                 raise TypeError()
             return n
         except TypeError:
             raise error.Abort('changeset references must be full hexadecimal '
                              'node identifiers')
 
     if opts.get('delete'):
         indices = []
         for v in opts.get('delete'):
             try:
                 indices.append(int(v))
             except ValueError:
                 raise error.Abort(_('invalid index value: %r') % v,
                                   hint=_('use integers for indices'))
 
         if repo.currenttransaction():
             raise error.Abort(_('cannot delete obsmarkers in the middle '
                                 'of transaction.'))
 
         with repo.lock():
             n = repair.deleteobsmarkers(repo.obsstore, indices)
             ui.write(_('deleted %i obsolescence markers\n') % n)
 
         return
 
     if precursor is not None:
         if opts['rev']:
             raise error.Abort('cannot select revision when creating marker')
         metadata = {}
         metadata['user'] = opts['user'] or ui.username()
         succs = tuple(parsenodeid(succ) for succ in successors)
         l = repo.lock()
         try:
             tr = repo.transaction('debugobsolete')
             try:
                 date = opts.get('date')
                 if date:
                     date = util.parsedate(date)
                 else:
                     date = None
                 prec = parsenodeid(precursor)
                 parents = None
                 if opts['record_parents']:
                     if prec not in repo.unfiltered():
                         raise error.Abort('cannot used --record-parents on '
                                          'unknown changesets')
                     parents = repo.unfiltered()[prec].parents()
                     parents = tuple(p.node() for p in parents)
                 repo.obsstore.create(tr, prec, succs, opts['flags'],
                                      parents=parents, date=date,
                                      metadata=metadata)
                 tr.close()
             except ValueError as exc:
                 raise error.Abort(_('bad obsmarker input: %s') % exc)
             finally:
                 tr.release()
         finally:
             l.release()
     else:
         if opts['rev']:
             revs = scmutil.revrange(repo, opts['rev'])
             nodes = [repo[r].node() for r in revs]
             markers = list(obsolete.getmarkers(repo, nodes=nodes))
             markers.sort(key=lambda x: x._data)
         else:
             markers = obsolete.getmarkers(repo)
 
         markerstoiter = markers
         isrelevant = lambda m: True
         if opts.get('rev') and opts.get('index'):
             markerstoiter = obsolete.getmarkers(repo)
             markerset = set(markers)
             isrelevant = lambda m: m in markerset
 
         fm = ui.formatter('debugobsolete', opts)
         for i, m in enumerate(markerstoiter):
             if not isrelevant(m):
                 # marker can be irrelevant when we're iterating over a set
                 # of markers (markerstoiter) which is bigger than the set
                 # of markers we want to display (markers)
                 # this can happen if both --index and --rev options are
                 # provided and thus we need to iterate over all of the markers
                 # to get the correct indices, but only display the ones that
                 # are relevant to --rev value
                 continue
             fm.startitem()
             ind = i if opts.get('index') else None
             cmdutil.showmarker(fm, m, index=ind)
         fm.end()
 
 @command('debugpathcomplete',
          [('f', 'full', None, _('complete an entire path')),
           ('n', 'normal', None, _('show only normal files')),
           ('a', 'added', None, _('show only added files')),
           ('r', 'removed', None, _('show only removed files'))],
          _('FILESPEC...'))
 def debugpathcomplete(ui, repo, *specs, **opts):
     '''complete part or all of a tracked path
 
     This command supports shells that offer path name completion. It
     currently completes only files already known to the dirstate.
 
     Completion extends only to the next path segment unless
     --full is specified, in which case entire paths are used.'''
 
     def complete(path, acceptable):
         dirstate = repo.dirstate
         spec = os.path.normpath(os.path.join(pycompat.getcwd(), path))
         rootdir = repo.root + pycompat.ossep
         if spec != repo.root and not spec.startswith(rootdir):
             return [], []
         if os.path.isdir(spec):
             spec += '/'
         spec = spec[len(rootdir):]
         fixpaths = pycompat.ossep != '/'
         if fixpaths:
             spec = spec.replace(pycompat.ossep, '/')
         speclen = len(spec)
         fullpaths = opts['full']
         files, dirs = set(), set()
         adddir, addfile = dirs.add, files.add
         for f, st in dirstate.iteritems():
             if f.startswith(spec) and st[0] in acceptable:
                 if fixpaths:
                     f = f.replace('/', pycompat.ossep)
                 if fullpaths:
                     addfile(f)
                     continue
                 s = f.find(pycompat.ossep, speclen)
                 if s >= 0:
                     adddir(f[:s])
                 else:
                     addfile(f)
         return files, dirs
 
     acceptable = ''
     if opts['normal']:
         acceptable += 'nm'
     if opts['added']:
         acceptable += 'a'
     if opts['removed']:
         acceptable += 'r'
     cwd = repo.getcwd()
     if not specs:
         specs = ['.']
 
     files, dirs = set(), set()
     for spec in specs:
         f, d = complete(spec, acceptable or 'nmar')
         files.update(f)
         dirs.update(d)
     files.update(dirs)
     ui.write('\n'.join(repo.pathto(p, cwd) for p in sorted(files)))
     ui.write('\n')
 
 @command('debugpushkey', [], _('REPO NAMESPACE [KEY OLD NEW]'), norepo=True)
 def debugpushkey(ui, repopath, namespace, *keyinfo, **opts):
     '''access the pushkey key/value protocol
 
     With two args, list the keys in the given namespace.
 
     With five args, set a key to new if it currently is set to old.
     Reports success or failure.
     '''
 
     target = hg.peer(ui, {}, repopath)
     if keyinfo:
         key, old, new = keyinfo
         r = target.pushkey(namespace, key, old, new)
         ui.status(str(r) + '\n')
         return not r
     else:
         for k, v in sorted(target.listkeys(namespace).iteritems()):
             ui.write("%s\t%s\n" % (k.encode('string-escape'),
                                    v.encode('string-escape')))
 
 @command('debugpvec', [], _('A B'))
 def debugpvec(ui, repo, a, b=None):
     ca = scmutil.revsingle(repo, a)
     cb = scmutil.revsingle(repo, b)
     pa = pvec.ctxpvec(ca)
     pb = pvec.ctxpvec(cb)
     if pa == pb:
         rel = "="
     elif pa > pb:
         rel = ">"
     elif pa < pb:
         rel = "<"
     elif pa | pb:
         rel = "|"
     ui.write(_("a: %s\n") % pa)
     ui.write(_("b: %s\n") % pb)
     ui.write(_("depth(a): %d depth(b): %d\n") % (pa._depth, pb._depth))
     ui.write(_("delta: %d hdist: %d distance: %d relation: %s\n") %
              (abs(pa._depth - pb._depth), pvec._hamming(pa._vec, pb._vec),
               pa.distance(pb), rel))
 
 @command('debugrebuilddirstate|debugrebuildstate',
     [('r', 'rev', '', _('revision to rebuild to'), _('REV')),
      ('', 'minimal', None, _('only rebuild files that are inconsistent with '
                              'the working copy parent')),
     ],
     _('[-r REV]'))
 def debugrebuilddirstate(ui, repo, rev, **opts):
     """rebuild the dirstate as it would look like for the given revision
 
     If no revision is specified the first current parent will be used.
 
     The dirstate will be set to the files of the given revision.
     The actual working directory content or existing dirstate
     information such as adds or removes is not considered.
 
     ``minimal`` will only rebuild the dirstate status for files that claim to be
     tracked but are not in the parent manifest, or that exist in the parent
     manifest but are not in the dirstate. It will not change adds, removes, or
     modified files that are in the working copy parent.
 
     One use of this command is to make the next :hg:`status` invocation
     check the actual file content.
     """
     ctx = scmutil.revsingle(repo, rev)
     with repo.wlock():
         dirstate = repo.dirstate
         changedfiles = None
         # See command doc for what minimal does.
         if opts.get('minimal'):
             manifestfiles = set(ctx.manifest().keys())
             dirstatefiles = set(dirstate)
             manifestonly = manifestfiles - dirstatefiles
             dsonly = dirstatefiles - manifestfiles
             dsnotadded = set(f for f in dsonly if dirstate[f] != 'a')
             changedfiles = manifestonly | dsnotadded
 
         dirstate.rebuild(ctx.node(), ctx.manifest(), changedfiles)
 
 @command('debugrebuildfncache', [], '')
 def debugrebuildfncache(ui, repo):
     """rebuild the fncache file"""
     repair.rebuildfncache(ui, repo)
 
 @command('debugrename',
     [('r', 'rev', '', _('revision to debug'), _('REV'))],
     _('[-r REV] FILE'))
 def debugrename(ui, repo, file1, *pats, **opts):
     """dump rename information"""
 
     ctx = scmutil.revsingle(repo, opts.get('rev'))
     m = scmutil.match(ctx, (file1,) + pats, opts)
     for abs in ctx.walk(m):
         fctx = ctx[abs]
         o = fctx.filelog().renamed(fctx.filenode())
         rel = m.rel(abs)
         if o:
             ui.write(_("%s renamed from %s:%s\n") % (rel, o[0], hex(o[1])))
         else:
             ui.write(_("%s not renamed\n") % rel)
 
 @command('debugrevlog', debugrevlogopts +
     [('d', 'dump', False, _('dump index data'))],
     _('-c|-m|FILE'),
     optionalrepo=True)
 def debugrevlog(ui, repo, file_=None, **opts):
     """show data and statistics about a revlog"""
     r = cmdutil.openrevlog(repo, 'debugrevlog', file_, opts)
 
     if opts.get("dump"):
         numrevs = len(r)
         ui.write(("# rev p1rev p2rev start   end deltastart base   p1   p2"
                  " rawsize totalsize compression heads chainlen\n"))
         ts = 0
         heads = set()
 
         for rev in xrange(numrevs):
             dbase = r.deltaparent(rev)
             if dbase == -1:
                 dbase = rev
             cbase = r.chainbase(rev)
             clen = r.chainlen(rev)
             p1, p2 = r.parentrevs(rev)
             rs = r.rawsize(rev)
             ts = ts + rs
             heads -= set(r.parentrevs(rev))
             heads.add(rev)
             try:
                 compression = ts / r.end(rev)
             except ZeroDivisionError:
                 compression = 0
             ui.write("%5d %5d %5d %5d %5d %10d %4d %4d %4d %7d %9d "
                      "%11d %5d %8d\n" %
                      (rev, p1, p2, r.start(rev), r.end(rev),
                       r.start(dbase), r.start(cbase),
                       r.start(p1), r.start(p2),
                       rs, ts, compression, len(heads), clen))
         return 0
 
     v = r.version
     format = v & 0xFFFF
     flags = []
     gdelta = False
     if v & revlog.REVLOGNGINLINEDATA:
         flags.append('inline')
     if v & revlog.REVLOGGENERALDELTA:
         gdelta = True
         flags.append('generaldelta')
     if not flags:
         flags = ['(none)']
 
     nummerges = 0
     numfull = 0
     numprev = 0
     nump1 = 0
     nump2 = 0
     numother = 0
     nump1prev = 0
     nump2prev = 0
     chainlengths = []
 
     datasize = [None, 0, 0]
     fullsize = [None, 0, 0]
     deltasize = [None, 0, 0]
     chunktypecounts = {}
     chunktypesizes = {}
 
     def addsize(size, l):
         if l[0] is None or size < l[0]:
             l[0] = size
         if size > l[1]:
             l[1] = size
         l[2] += size
 
     numrevs = len(r)
     for rev in xrange(numrevs):
         p1, p2 = r.parentrevs(rev)
         delta = r.deltaparent(rev)
         if format > 0:
             addsize(r.rawsize(rev), datasize)
         if p2 != nullrev:
             nummerges += 1
         size = r.length(rev)
         if delta == nullrev:
             chainlengths.append(0)
             numfull += 1
             addsize(size, fullsize)
         else:
             chainlengths.append(chainlengths[delta] + 1)
             addsize(size, deltasize)
             if delta == rev - 1:
                 numprev += 1
                 if delta == p1:
                     nump1prev += 1
                 elif delta == p2:
                     nump2prev += 1
             elif delta == p1:
                 nump1 += 1
             elif delta == p2:
                 nump2 += 1
             elif delta != nullrev:
                 numother += 1
 
         # Obtain data on the raw chunks in the revlog.
         chunk = r._chunkraw(rev, rev)[1]
         if chunk:
             chunktype = chunk[0]
         else:
             chunktype = 'empty'
 
         if chunktype not in chunktypecounts:
             chunktypecounts[chunktype] = 0
             chunktypesizes[chunktype] = 0
 
         chunktypecounts[chunktype] += 1
         chunktypesizes[chunktype] += size
 
     # Adjust size min value for empty cases
     for size in (datasize, fullsize, deltasize):
         if size[0] is None:
             size[0] = 0
 
     numdeltas = numrevs - numfull
     numoprev = numprev - nump1prev - nump2prev
     totalrawsize = datasize[2]
     datasize[2] /= numrevs
     fulltotal = fullsize[2]
     fullsize[2] /= numfull
     deltatotal = deltasize[2]
     if numrevs - numfull > 0:
         deltasize[2] /= numrevs - numfull
     totalsize = fulltotal + deltatotal
     avgchainlen = sum(chainlengths) / numrevs
     maxchainlen = max(chainlengths)
     compratio = 1
     if totalsize:
         compratio = totalrawsize / totalsize
 
     basedfmtstr = '%%%dd\n'
     basepcfmtstr = '%%%dd %s(%%5.2f%%%%)\n'
 
     def dfmtstr(max):
         return basedfmtstr % len(str(max))
     def pcfmtstr(max, padding=0):
         return basepcfmtstr % (len(str(max)), ' ' * padding)
 
     def pcfmt(value, total):
         if total:
             return (value, 100 * float(value) / total)
         else:
             return value, 100.0
 
     ui.write(('format : %d\n') % format)
     ui.write(('flags  : %s\n') % ', '.join(flags))
 
     ui.write('\n')
     fmt = pcfmtstr(totalsize)
     fmt2 = dfmtstr(totalsize)
     ui.write(('revisions     : ') + fmt2 % numrevs)
     ui.write(('    merges    : ') + fmt % pcfmt(nummerges, numrevs))
     ui.write(('    normal    : ') + fmt % pcfmt(numrevs - nummerges, numrevs))
     ui.write(('revisions     : ') + fmt2 % numrevs)
     ui.write(('    full      : ') + fmt % pcfmt(numfull, numrevs))
     ui.write(('    deltas    : ') + fmt % pcfmt(numdeltas, numrevs))
     ui.write(('revision size : ') + fmt2 % totalsize)
     ui.write(('    full      : ') + fmt % pcfmt(fulltotal, totalsize))
     ui.write(('    deltas    : ') + fmt % pcfmt(deltatotal, totalsize))
 
     def fmtchunktype(chunktype):
         if chunktype == 'empty':
             return '    %s     : ' % chunktype
         elif chunktype in string.ascii_letters:
             return '    0x%s (%s)  : ' % (hex(chunktype), chunktype)
         else:
             return '    0x%s      : ' % hex(chunktype)
 
     ui.write('\n')
     ui.write(('chunks        : ') + fmt2 % numrevs)
     for chunktype in sorted(chunktypecounts):
         ui.write(fmtchunktype(chunktype))
         ui.write(fmt % pcfmt(chunktypecounts[chunktype], numrevs))
     ui.write(('chunks size   : ') + fmt2 % totalsize)
     for chunktype in sorted(chunktypecounts):
         ui.write(fmtchunktype(chunktype))
         ui.write(fmt % pcfmt(chunktypesizes[chunktype], totalsize))
 
     ui.write('\n')
     fmt = dfmtstr(max(avgchainlen, compratio))
     ui.write(('avg chain length  : ') + fmt % avgchainlen)
     ui.write(('max chain length  : ') + fmt % maxchainlen)
     ui.write(('compression ratio : ') + fmt % compratio)
 
     if format > 0:
         ui.write('\n')
         ui.write(('uncompressed data size (min/max/avg) : %d / %d / %d\n')
                  % tuple(datasize))
     ui.write(('full revision size (min/max/avg)     : %d / %d / %d\n')
              % tuple(fullsize))
     ui.write(('delta size (min/max/avg)             : %d / %d / %d\n')
              % tuple(deltasize))
 
     if numdeltas > 0:
         ui.write('\n')
         fmt = pcfmtstr(numdeltas)
         fmt2 = pcfmtstr(numdeltas, 4)
         ui.write(('deltas against prev  : ') + fmt % pcfmt(numprev, numdeltas))
         if numprev > 0:
             ui.write(('    where prev = p1  : ') + fmt2 % pcfmt(nump1prev,
                                                               numprev))
             ui.write(('    where prev = p2  : ') + fmt2 % pcfmt(nump2prev,
                                                               numprev))
             ui.write(('    other            : ') + fmt2 % pcfmt(numoprev,
                                                               numprev))
         if gdelta:
             ui.write(('deltas against p1    : ')
                      + fmt % pcfmt(nump1, numdeltas))
             ui.write(('deltas against p2    : ')
                      + fmt % pcfmt(nump2, numdeltas))
             ui.write(('deltas against other : ') + fmt % pcfmt(numother,
                                                              numdeltas))
 
 @command('debugrevspec',
     [('', 'optimize', None,
       _('print parsed tree after optimizing (DEPRECATED)')),
      ('p', 'show-stage', [],
       _('print parsed tree at the given stage'), _('NAME')),
      ('', 'no-optimized', False, _('evaluate tree without optimization')),
      ('', 'verify-optimized', False, _('verify optimized result')),
      ],
     ('REVSPEC'))
 def debugrevspec(ui, repo, expr, **opts):
     """parse and apply a revision specification
 
     Use -p/--show-stage option to print the parsed tree at the given stages.
     Use -p all to print tree at every stage.
 
     Use --verify-optimized to compare the optimized result with the unoptimized
     one. Returns 1 if the optimized result differs.
     """
     stages = [
         ('parsed', lambda tree: tree),
         ('expanded', lambda tree: revset.expandaliases(ui, tree)),
         ('concatenated', revset.foldconcat),
         ('analyzed', revset.analyze),
         ('optimized', revset.optimize),
     ]
     if opts['no_optimized']:
         stages = stages[:-1]
     if opts['verify_optimized'] and opts['no_optimized']:
         raise error.Abort(_('cannot use --verify-optimized with '
                             '--no-optimized'))
     stagenames = set(n for n, f in stages)
 
     showalways = set()
     showchanged = set()
     if ui.verbose and not opts['show_stage']:
         # show parsed tree by --verbose (deprecated)
         showalways.add('parsed')
         showchanged.update(['expanded', 'concatenated'])
         if opts['optimize']:
             showalways.add('optimized')
     if opts['show_stage'] and opts['optimize']:
         raise error.Abort(_('cannot use --optimize with --show-stage'))
     if opts['show_stage'] == ['all']:
         showalways.update(stagenames)
     else:
         for n in opts['show_stage']:
             if n not in stagenames:
                 raise error.Abort(_('invalid stage name: %s') % n)
         showalways.update(opts['show_stage'])
 
     treebystage = {}
     printedtree = None
     tree = revset.parse(expr, lookup=repo.__contains__)
     for n, f in stages:
         treebystage[n] = tree = f(tree)
         if n in showalways or (n in showchanged and tree != printedtree):
             if opts['show_stage'] or n != 'parsed':
                 ui.write(("* %s:\n") % n)
             ui.write(revset.prettyformat(tree), "\n")
             printedtree = tree
 
     if opts['verify_optimized']:
         arevs = revset.makematcher(treebystage['analyzed'])(repo)
         brevs = revset.makematcher(treebystage['optimized'])(repo)
         if ui.verbose:
             ui.note(("* analyzed set:\n"), revset.prettyformatset(arevs), "\n")
             ui.note(("* optimized set:\n"), revset.prettyformatset(brevs), "\n")
         arevs = list(arevs)
         brevs = list(brevs)
         if arevs == brevs:
             return 0
         ui.write(('--- analyzed\n'), label='diff.file_a')
         ui.write(('+++ optimized\n'), label='diff.file_b')
         sm = difflib.SequenceMatcher(None, arevs, brevs)
         for tag, alo, ahi, blo, bhi in sm.get_opcodes():
             if tag in ('delete', 'replace'):
                 for c in arevs[alo:ahi]:
                     ui.write('-%s\n' % c, label='diff.deleted')
             if tag in ('insert', 'replace'):
                 for c in brevs[blo:bhi]:
                     ui.write('+%s\n' % c, label='diff.inserted')
             if tag == 'equal':
                 for c in arevs[alo:ahi]:
                     ui.write(' %s\n' % c)
         return 1
 
     func = revset.makematcher(tree)
     revs = func(repo)
     if ui.verbose:
         ui.note(("* set:\n"), revset.prettyformatset(revs), "\n")
     for c in revs:
         ui.write("%s\n" % c)
 
 @command('debugsetparents', [], _('REV1 [REV2]'))
 def debugsetparents(ui, repo, rev1, rev2=None):
     """manually set the parents of the current working directory
 
     This is useful for writing repository conversion tools, but should
     be used with care. For example, neither the working directory nor the
     dirstate is updated, so file status may be incorrect after running this
     command.
 
     Returns 0 on success.
     """
 
     r1 = scmutil.revsingle(repo, rev1).node()
     r2 = scmutil.revsingle(repo, rev2, 'null').node()
 
     with repo.wlock():
         repo.setparents(r1, r2)
 
 @command('debugdirstate|debugstate',
     [('', 'nodates', None, _('do not display the saved mtime')),
     ('', 'datesort', None, _('sort by saved mtime'))],
     _('[OPTION]...'))
 def debugstate(ui, repo, **opts):
     """show the contents of the current dirstate"""
 
     nodates = opts.get('nodates')
     datesort = opts.get('datesort')
 
     timestr = ""
     if datesort:
         keyfunc = lambda x: (x[1][3], x[0]) # sort by mtime, then by filename
     else:
         keyfunc = None # sort by filename
     for file_, ent in sorted(repo.dirstate._map.iteritems(), key=keyfunc):
         if ent[3] == -1:
             timestr = 'unset               '
         elif nodates:
             timestr = 'set                 '
         else:
             timestr = time.strftime("%Y-%m-%d %H:%M:%S ",
                                     time.localtime(ent[3]))
         if ent[1] & 0o20000:
             mode = 'lnk'
         else:
             mode = '%3o' % (ent[1] & 0o777 & ~util.umask)
         ui.write("%c %s %10d %s%s\n" % (ent[0], mode, ent[2], timestr, file_))
     for f in repo.dirstate.copies():
         ui.write(_("copy: %s -> %s\n") % (repo.dirstate.copied(f), f))
 
 @command('debugsub',
     [('r', 'rev', '',
      _('revision to check'), _('REV'))],
     _('[-r REV] [REV]'))
 def debugsub(ui, repo, rev=None):
     ctx = scmutil.revsingle(repo, rev, None)
     for k, v in sorted(ctx.substate.items()):
         ui.write(('path %s\n') % k)
         ui.write((' source   %s\n') % v[0])
         ui.write((' revision %s\n') % v[1])
 
 @command('debugsuccessorssets',
     [],
     _('[REV]'))
 def debugsuccessorssets(ui, repo, *revs):
     """show set of successors for revision
 
     A successors set of changeset A is a consistent group of revisions that
     succeed A. It contains non-obsolete changesets only.
 
     In most cases a changeset A has a single successors set containing a single
     successor (changeset A replaced by A').
 
     A changeset that is made obsolete with no successors are called "pruned".
     Such changesets have no successors sets at all.
 
     A changeset that has been "split" will have a successors set containing
     more than one successor.
 
     A changeset that has been rewritten in multiple different ways is called
     "divergent". Such changesets have multiple successor sets (each of which
     may also be split, i.e. have multiple successors).
 
     Results are displayed as follows::
 
         <rev1>
             <successors-1A>
         <rev2>
             <successors-2A>
             <successors-2B1> <successors-2B2> <successors-2B3>
 
     Here rev2 has two possible (i.e. divergent) successors sets. The first
     holds one element, whereas the second holds three (i.e. the changeset has
     been split).
     """
     # passed to successorssets caching computation from one call to another
     cache = {}
     ctx2str = str
     node2str = short
     if ui.debug():
         def ctx2str(ctx):
             return ctx.hex()
         node2str = hex
     for rev in scmutil.revrange(repo, revs):
         ctx = repo[rev]
         ui.write('%s\n'% ctx2str(ctx))
         for succsset in obsolete.successorssets(repo, ctx.node(), cache):
             if succsset:
                 ui.write('    ')
                 ui.write(node2str(succsset[0]))
                 for node in succsset[1:]:
                     ui.write(' ')
                     ui.write(node2str(node))
             ui.write('\n')
 
 @command('debugtemplate',
     [('r', 'rev', [], _('apply template on changesets'), _('REV')),
      ('D', 'define', [], _('define template keyword'), _('KEY=VALUE'))],
     _('[-r REV]... [-D KEY=VALUE]... TEMPLATE'),
     optionalrepo=True)
 def debugtemplate(ui, repo, tmpl, **opts):
     """parse and apply a template
 
     If -r/--rev is given, the template is processed as a log template and
     applied to the given changesets. Otherwise, it is processed as a generic
     template.
 
     Use --verbose to print the parsed tree.
     """
     revs = None
     if opts['rev']:
         if repo is None:
             raise error.RepoError(_('there is no Mercurial repository here '
                                     '(.hg not found)'))
         revs = scmutil.revrange(repo, opts['rev'])
 
     props = {}
     for d in opts['define']:
         try:
             k, v = (e.strip() for e in d.split('=', 1))
             if not k:
                 raise ValueError
             props[k] = v
         except ValueError:
             raise error.Abort(_('malformed keyword definition: %s') % d)
 
     if ui.verbose:
         aliases = ui.configitems('templatealias')
         tree = templater.parse(tmpl)
         ui.note(templater.prettyformat(tree), '\n')
         newtree = templater.expandaliases(tree, aliases)
         if newtree != tree:
             ui.note(("* expanded:\n"), templater.prettyformat(newtree), '\n')
 
     mapfile = None
     if revs is None:
         k = 'debugtemplate'
         t = formatter.maketemplater(ui, k, tmpl)
         ui.write(templater.stringify(t(k, **props)))
     else:
         displayer = cmdutil.changeset_templater(ui, repo, None, opts, tmpl,
                                                 mapfile, buffered=False)
         for r in revs:
             displayer.show(repo[r], **props)
         displayer.close()
 
 @command('debugwalk', walkopts, _('[OPTION]... [FILE]...'), inferrepo=True)
 def debugwalk(ui, repo, *pats, **opts):
     """show how files match on given patterns"""
     m = scmutil.match(repo[None], pats, opts)
     items = list(repo.walk(m))
     if not items:
         return
     f = lambda fn: fn
     if ui.configbool('ui', 'slash') and pycompat.ossep != '/':
         f = lambda fn: util.normpath(fn)
     fmt = 'f  %%-%ds  %%-%ds  %%s' % (
         max([len(abs) for abs in items]),
         max([len(m.rel(abs)) for abs in items]))
     for abs in items:
         line = fmt % (abs, f(m.rel(abs)), m.exact(abs) and 'exact' or '')
         ui.write("%s\n" % line.rstrip())
 
 @command('debugwireargs',
     [('', 'three', '', 'three'),
     ('', 'four', '', 'four'),
     ('', 'five', '', 'five'),
     ] + remoteopts,
     _('REPO [OPTIONS]... [ONE [TWO]]'),
     norepo=True)
 def debugwireargs(ui, repopath, *vals, **opts):
     repo = hg.peer(ui, opts, repopath)
     for opt in remoteopts:
         del opts[opt[1]]
     args = {}
     for k, v in opts.iteritems():
         if v:
             args[k] = v
     # run twice to check that we don't mess up the stream for the next command
     res1 = repo.debugwireargs(*vals, **args)
     res2 = repo.debugwireargs(*vals, **args)
     ui.write("%s\n" % res1)
     if res1 != res2:
         ui.warn("%s\n" % res2)
 
 @command('^diff',
     [('r', 'rev', [], _('revision'), _('REV')),
     ('c', 'change', '', _('change made by revision'), _('REV'))
     ] + diffopts + diffopts2 + walkopts + subrepoopts,
     _('[OPTION]... ([-c REV] | [-r REV1 [-r REV2]]) [FILE]...'),
     inferrepo=True)
 def diff(ui, repo, *pats, **opts):
     """diff repository (or selected files)
 
     Show differences between revisions for the specified files.
 
     Differences between files are shown using the unified diff format.
 
     .. note::
 
        :hg:`diff` may generate unexpected results for merges, as it will
        default to comparing against the working directory's first
        parent changeset if no revisions are specified.
 
     When two revision arguments are given, then changes are shown
     between those revisions. If only one revision is specified then
     that revision is compared to the working directory, and, when no
     revisions are specified, the working directory files are compared
     to its first parent.
 
     Alternatively you can specify -c/--change with a revision to see
     the changes in that changeset relative to its first parent.
 
     Without the -a/--text option, diff will avoid generating diffs of
     files it detects as binary. With -a, diff will generate a diff
     anyway, probably with undesirable results.
 
     Use the -g/--git option to generate diffs in the git extended diff
     format. For more information, read :hg:`help diffs`.
 
     .. container:: verbose
 
       Examples:
 
       - compare a file in the current working directory to its parent::
 
           hg diff foo.c
 
       - compare two historical versions of a directory, with rename info::
 
           hg diff --git -r 1.0:1.2 lib/
 
       - get change stats relative to the last change on some date::
 
           hg diff --stat -r "date('may 2')"
 
       - diff all newly-added files that contain a keyword::
 
           hg diff "set:added() and grep(GNU)"
 
       - compare a revision and its parents::
 
           hg diff -c 9353         # compare against first parent
           hg diff -r 9353^:9353   # same using revset syntax
           hg diff -r 9353^2:9353  # compare against the second parent
 
     Returns 0 on success.
     """
 
     revs = opts.get('rev')
     change = opts.get('change')
     stat = opts.get('stat')
     reverse = opts.get('reverse')
 
     if revs and change:
         msg = _('cannot specify --rev and --change at the same time')
         raise error.Abort(msg)
     elif change:
         node2 = scmutil.revsingle(repo, change, None).node()
         node1 = repo[node2].p1().node()
     else:
         node1, node2 = scmutil.revpair(repo, revs)
 
     if reverse:
         node1, node2 = node2, node1
 
     diffopts = patch.diffallopts(ui, opts)
     m = scmutil.match(repo[node2], pats, opts)
     cmdutil.diffordiffstat(ui, repo, diffopts, node1, node2, m, stat=stat,
                            listsubrepos=opts.get('subrepos'),
                            root=opts.get('root'))
 
 @command('^export',
     [('o', 'output', '',
      _('print output to file with formatted name'), _('FORMAT')),
     ('', 'switch-parent', None, _('diff against the second parent')),
     ('r', 'rev', [], _('revisions to export'), _('REV')),
     ] + diffopts,
     _('[OPTION]... [-o OUTFILESPEC] [-r] [REV]...'))
 def export(ui, repo, *changesets, **opts):
     """dump the header and diffs for one or more changesets
 
     Print the changeset header and diffs for one or more revisions.
     If no revision is given, the parent of the working directory is used.
 
     The information shown in the changeset header is: author, date,
     branch name (if non-default), changeset hash, parent(s) and commit
     comment.
 
     .. note::
 
        :hg:`export` may generate unexpected diff output for merge
        changesets, as it will compare the merge changeset against its
        first parent only.
 
     Output may be to a file, in which case the name of the file is
     given using a format string. The formatting rules are as follows:
 
     :``%%``: literal "%" character
     :``%H``: changeset hash (40 hexadecimal digits)
     :``%N``: number of patches being generated
     :``%R``: changeset revision number
     :``%b``: basename of the exporting repository
     :``%h``: short-form changeset hash (12 hexadecimal digits)
     :``%m``: first line of the commit message (only alphanumeric characters)
     :``%n``: zero-padded sequence number, starting at 1
     :``%r``: zero-padded changeset revision number
 
     Without the -a/--text option, export will avoid generating diffs
     of files it detects as binary. With -a, export will generate a
     diff anyway, probably with undesirable results.
 
     Use the -g/--git option to generate diffs in the git extended diff
     format. See :hg:`help diffs` for more information.
 
     With the --switch-parent option, the diff will be against the
     second parent. It can be useful to review a merge.
 
     .. container:: verbose
 
       Examples:
 
       - use export and import to transplant a bugfix to the current
         branch::
 
           hg export -r 9353 | hg import -
 
       - export all the changesets between two revisions to a file with
         rename information::
 
           hg export --git -r 123:150 > changes.txt
 
       - split outgoing changes into a series of patches with
         descriptive names::
 
           hg export -r "outgoing()" -o "%n-%m.patch"
 
     Returns 0 on success.
     """
     changesets += tuple(opts.get('rev', []))
     if not changesets:
         changesets = ['.']
     revs = scmutil.revrange(repo, changesets)
     if not revs:
         raise error.Abort(_("export requires at least one changeset"))
     if len(revs) > 1:
         ui.note(_('exporting patches:\n'))
     else:
         ui.note(_('exporting patch:\n'))
     cmdutil.export(repo, revs, template=opts.get('output'),
                  switch_parent=opts.get('switch_parent'),
                  opts=patch.diffallopts(ui, opts))
 
 @command('files',
     [('r', 'rev', '', _('search the repository as it is in REV'), _('REV')),
      ('0', 'print0', None, _('end filenames with NUL, for use with xargs')),
     ] + walkopts + formatteropts + subrepoopts,
     _('[OPTION]... [FILE]...'))
 def files(ui, repo, *pats, **opts):
     """list tracked files
 
     Print files under Mercurial control in the working directory or
     specified revision for given files (excluding removed files).
     Files can be specified as filenames or filesets.
 
     If no files are given to match, this command prints the names
     of all files under Mercurial control.
 
     .. container:: verbose
 
       Examples:
 
       - list all files under the current directory::
 
           hg files .
 
       - shows sizes and flags for current revision::
 
           hg files -vr .
 
       - list all files named README::
 
           hg files -I "**/README"
 
       - list all binary files::
 
           hg files "set:binary()"
 
       - find files containing a regular expression::
 
           hg files "set:grep('bob')"
 
       - search tracked file contents with xargs and grep::
 
           hg files -0 | xargs -0 grep foo
 
     See :hg:`help patterns` and :hg:`help filesets` for more information
     on specifying file patterns.
 
     Returns 0 if a match is found, 1 otherwise.
 
     """
     ctx = scmutil.revsingle(repo, opts.get('rev'), None)
 
     end = '\n'
     if opts.get('print0'):
         end = '\0'
     fmt = '%s' + end
 
     m = scmutil.match(ctx, pats, opts)
     with ui.formatter('files', opts) as fm:
         return cmdutil.files(ui, ctx, m, fm, fmt, opts.get('subrepos'))
 
 @command('^forget', walkopts, _('[OPTION]... FILE...'), inferrepo=True)
 def forget(ui, repo, *pats, **opts):
     """forget the specified files on the next commit
 
     Mark the specified files so they will no longer be tracked
     after the next commit.
 
     This only removes files from the current branch, not from the
     entire project history, and it does not delete them from the
     working directory.
 
     To delete the file from the working directory, see :hg:`remove`.
 
     To undo a forget before the next commit, see :hg:`add`.
 
     .. container:: verbose
 
       Examples:
 
       - forget newly-added binary files::
 
           hg forget "set:added() and binary()"
 
       - forget files that would be excluded by .hgignore::
 
           hg forget "set:hgignore()"
 
     Returns 0 on success.
     """
 
     if not pats:
         raise error.Abort(_('no files specified'))
 
     m = scmutil.match(repo[None], pats, opts)
     rejected = cmdutil.forget(ui, repo, m, prefix="", explicitonly=False)[0]
     return rejected and 1 or 0
 
 @command(
     'graft',
     [('r', 'rev', [], _('revisions to graft'), _('REV')),
      ('c', 'continue', False, _('resume interrupted graft')),
      ('e', 'edit', False, _('invoke editor on commit messages')),
      ('', 'log', None, _('append graft info to log message')),
      ('f', 'force', False, _('force graft')),
      ('D', 'currentdate', False,
       _('record the current date as commit date')),
      ('U', 'currentuser', False,
       _('record the current user as committer'), _('DATE'))]
     + commitopts2 + mergetoolopts  + dryrunopts,
     _('[OPTION]... [-r REV]... REV...'))
 def graft(ui, repo, *revs, **opts):
     '''copy changes from other branches onto the current branch
 
     This command uses Mercurial's merge logic to copy individual
     changes from other branches without merging branches in the
     history graph. This is sometimes known as 'backporting' or
     'cherry-picking'. By default, graft will copy user, date, and
     description from the source changesets.
 
     Changesets that are ancestors of the current revision, that have
     already been grafted, or that are merges will be skipped.
 
     If --log is specified, log messages will have a comment appended
     of the form::
 
       (grafted from CHANGESETHASH)
 
     If --force is specified, revisions will be grafted even if they
     are already ancestors of or have been grafted to the destination.
     This is useful when the revisions have since been backed out.
 
     If a graft merge results in conflicts, the graft process is
     interrupted so that the current merge can be manually resolved.
     Once all conflicts are addressed, the graft process can be
     continued with the -c/--continue option.
 
     .. note::
 
        The -c/--continue option does not reapply earlier options, except
        for --force.
 
     .. container:: verbose
 
       Examples:
 
       - copy a single change to the stable branch and edit its description::
 
           hg update stable
           hg graft --edit 9393
 
       - graft a range of changesets with one exception, updating dates::
 
           hg graft -D "2085::2093 and not 2091"
 
       - continue a graft after resolving conflicts::
 
           hg graft -c
 
       - show the source of a grafted changeset::
 
           hg log --debug -r .
 
       - show revisions sorted by date::
 
           hg log -r "sort(all(), date)"
 
     See :hg:`help revisions` and :hg:`help revsets` for more about
     specifying revisions.
 
     Returns 0 on successful completion.
     '''
     with repo.wlock():
         return _dograft(ui, repo, *revs, **opts)
 
 def _dograft(ui, repo, *revs, **opts):
     if revs and opts.get('rev'):
         ui.warn(_('warning: inconsistent use of --rev might give unexpected '
                   'revision ordering!\n'))
 
     revs = list(revs)
     revs.extend(opts.get('rev'))
 
     if not opts.get('user') and opts.get('currentuser'):
         opts['user'] = ui.username()
     if not opts.get('date') and opts.get('currentdate'):
         opts['date'] = "%d %d" % util.makedate()
 
     editor = cmdutil.getcommiteditor(editform='graft', **opts)
 
     cont = False
     if opts.get('continue'):
         cont = True
         if revs:
             raise error.Abort(_("can't specify --continue and revisions"))
         # read in unfinished revisions
         try:
             nodes = repo.vfs.read('graftstate').splitlines()
             revs = [repo[node].rev() for node in nodes]
         except IOError as inst:
             if inst.errno != errno.ENOENT:
                 raise
             cmdutil.wrongtooltocontinue(repo, _('graft'))
     else:
         cmdutil.checkunfinished(repo)
         cmdutil.bailifchanged(repo)
         if not revs:
             raise error.Abort(_('no revisions specified'))
         revs = scmutil.revrange(repo, revs)
 
     skipped = set()
     # check for merges
     for rev in repo.revs('%ld and merge()', revs):
         ui.warn(_('skipping ungraftable merge revision %s\n') % rev)
         skipped.add(rev)
     revs = [r for r in revs if r not in skipped]
     if not revs:
         return -1
 
     # Don't check in the --continue case, in effect retaining --force across
     # --continues. That's because without --force, any revisions we decided to
     # skip would have been filtered out here, so they wouldn't have made their
     # way to the graftstate. With --force, any revisions we would have otherwise
     # skipped would not have been filtered out, and if they hadn't been applied
     # already, they'd have been in the graftstate.
     if not (cont or opts.get('force')):
         # check for ancestors of dest branch
         crev = repo['.'].rev()
         ancestors = repo.changelog.ancestors([crev], inclusive=True)
         # XXX make this lazy in the future
         # don't mutate while iterating, create a copy
         for rev in list(revs):
             if rev in ancestors:
                 ui.warn(_('skipping ancestor revision %d:%s\n') %
                         (rev, repo[rev]))
                 # XXX remove on list is slow
                 revs.remove(rev)
         if not revs:
             return -1
 
         # analyze revs for earlier grafts
         ids = {}
         for ctx in repo.set("%ld", revs):
             ids[ctx.hex()] = ctx.rev()
             n = ctx.extra().get('source')
             if n:
                 ids[n] = ctx.rev()
 
         # check ancestors for earlier grafts
         ui.debug('scanning for duplicate grafts\n')
 
         for rev in repo.changelog.findmissingrevs(revs, [crev]):
             ctx = repo[rev]
             n = ctx.extra().get('source')
             if n in ids:
                 try:
                     r = repo[n].rev()
                 except error.RepoLookupError:
                     r = None
                 if r in revs:
                     ui.warn(_('skipping revision %d:%s '
                               '(already grafted to %d:%s)\n')
                             % (r, repo[r], rev, ctx))
                     revs.remove(r)
                 elif ids[n] in revs:
                     if r is None:
                         ui.warn(_('skipping already grafted revision %d:%s '
                                   '(%d:%s also has unknown origin %s)\n')
                                 % (ids[n], repo[ids[n]], rev, ctx, n[:12]))
                     else:
                         ui.warn(_('skipping already grafted revision %d:%s '
                                   '(%d:%s also has origin %d:%s)\n')
                                 % (ids[n], repo[ids[n]], rev, ctx, r, n[:12]))
                     revs.remove(ids[n])
             elif ctx.hex() in ids:
                 r = ids[ctx.hex()]
                 ui.warn(_('skipping already grafted revision %d:%s '
                           '(was grafted from %d:%s)\n') %
                         (r, repo[r], rev, ctx))
                 revs.remove(r)
         if not revs:
             return -1
 
     for pos, ctx in enumerate(repo.set("%ld", revs)):
         desc = '%d:%s "%s"' % (ctx.rev(), ctx,
                                ctx.description().split('\n', 1)[0])
         names = repo.nodetags(ctx.node()) + repo.nodebookmarks(ctx.node())
         if names:
             desc += ' (%s)' % ' '.join(names)
         ui.status(_('grafting %s\n') % desc)
         if opts.get('dry_run'):
             continue
 
         source = ctx.extra().get('source')
         extra = {}
         if source:
             extra['source'] = source
             extra['intermediate-source'] = ctx.hex()
         else:
             extra['source'] = ctx.hex()
         user = ctx.user()
         if opts.get('user'):
             user = opts['user']
         date = ctx.date()
         if opts.get('date'):
             date = opts['date']
         message = ctx.description()
         if opts.get('log'):
             message += '\n(grafted from %s)' % ctx.hex()
 
         # we don't merge the first commit when continuing
         if not cont:
             # perform the graft merge with p1(rev) as 'ancestor'
             try:
                 # ui.forcemerge is an internal variable, do not document
                 repo.ui.setconfig('ui', 'forcemerge', opts.get('tool', ''),
                                   'graft')
                 stats = mergemod.graft(repo, ctx, ctx.p1(),
                                        ['local', 'graft'])
             finally:
                 repo.ui.setconfig('ui', 'forcemerge', '', 'graft')
             # report any conflicts
             if stats and stats[3] > 0:
                 # write out state for --continue
                 nodelines = [repo[rev].hex() + "\n" for rev in revs[pos:]]
                 repo.vfs.write('graftstate', ''.join(nodelines))
                 extra = ''
                 if opts.get('user'):
                     extra += ' --user %s' % util.shellquote(opts['user'])
                 if opts.get('date'):
                     extra += ' --date %s' % util.shellquote(opts['date'])
                 if opts.get('log'):
                     extra += ' --log'
                 hint=_("use 'hg resolve' and 'hg graft --continue%s'") % extra
                 raise error.Abort(
                     _("unresolved conflicts, can't continue"),
                     hint=hint)
         else:
             cont = False
 
         # commit
         node = repo.commit(text=message, user=user,
                     date=date, extra=extra, editor=editor)
         if node is None:
             ui.warn(
                 _('note: graft of %d:%s created no changes to commit\n') %
                 (ctx.rev(), ctx))
 
     # remove state when we complete successfully
     if not opts.get('dry_run'):
         util.unlinkpath(repo.join('graftstate'), ignoremissing=True)
 
     return 0
 
 @command('grep',
     [('0', 'print0', None, _('end fields with NUL')),
     ('', 'all', None, _('print all revisions that match')),
     ('a', 'text', None, _('treat all files as text')),
     ('f', 'follow', None,
      _('follow changeset history,'
        ' or file history across copies and renames')),
     ('i', 'ignore-case', None, _('ignore case when matching')),
     ('l', 'files-with-matches', None,
      _('print only filenames and revisions that match')),
     ('n', 'line-number', None, _('print matching line numbers')),
     ('r', 'rev', [],
      _('only search files changed within revision range'), _('REV')),
     ('u', 'user', None, _('list the author (long with -v)')),
     ('d', 'date', None, _('list the date (short with -q)')),
     ] + formatteropts + walkopts,
     _('[OPTION]... PATTERN [FILE]...'),
     inferrepo=True)
 def grep(ui, repo, pattern, *pats, **opts):
     """search revision history for a pattern in specified files
 
     Search revision history for a regular expression in the specified
     files or the entire project.
 
     By default, grep prints the most recent revision number for each
     file in which it finds a match. To get it to print every revision
     that contains a change in match status ("-" for a match that becomes
     a non-match, or "+" for a non-match that becomes a match), use the
     --all flag.
 
     PATTERN can be any Python (roughly Perl-compatible) regular
     expression.
 
     If no FILEs are specified (and -f/--follow isn't set), all files in
     the repository are searched, including those that don't exist in the
     current branch or have been deleted in a prior changeset.
 
     Returns 0 if a match is found, 1 otherwise.
     """
     reflags = re.M
     if opts.get('ignore_case'):
         reflags |= re.I
     try:
         regexp = util.re.compile(pattern, reflags)
     except re.error as inst:
         ui.warn(_("grep: invalid match pattern: %s\n") % inst)
         return 1
     sep, eol = ':', '\n'
     if opts.get('print0'):
         sep = eol = '\0'
 
     getfile = util.lrucachefunc(repo.file)
 
     def matchlines(body):
         begin = 0
         linenum = 0
         while begin < len(body):
             match = regexp.search(body, begin)
             if not match:
                 break
             mstart, mend = match.span()
             linenum += body.count('\n', begin, mstart) + 1
             lstart = body.rfind('\n', begin, mstart) + 1 or begin
             begin = body.find('\n', mend) + 1 or len(body) + 1
             lend = begin - 1
             yield linenum, mstart - lstart, mend - lstart, body[lstart:lend]
 
     class linestate(object):
         def __init__(self, line, linenum, colstart, colend):
             self.line = line
             self.linenum = linenum
             self.colstart = colstart
             self.colend = colend
 
         def __hash__(self):
             return hash((self.linenum, self.line))
 
         def __eq__(self, other):
             return self.line == other.line
 
         def findpos(self):
             """Iterate all (start, end) indices of matches"""
             yield self.colstart, self.colend
             p = self.colend
             while p < len(self.line):
                 m = regexp.search(self.line, p)
                 if not m:
                     break
                 yield m.span()
                 p = m.end()
 
     matches = {}
     copies = {}
     def grepbody(fn, rev, body):
         matches[rev].setdefault(fn, [])
         m = matches[rev][fn]
         for lnum, cstart, cend, line in matchlines(body):
             s = linestate(line, lnum, cstart, cend)
             m.append(s)
 
     def difflinestates(a, b):
         sm = difflib.SequenceMatcher(None, a, b)
         for tag, alo, ahi, blo, bhi in sm.get_opcodes():
             if tag == 'insert':
                 for i in xrange(blo, bhi):
                     yield ('+', b[i])
             elif tag == 'delete':
                 for i in xrange(alo, ahi):
                     yield ('-', a[i])
             elif tag == 'replace':
                 for i in xrange(alo, ahi):
                     yield ('-', a[i])
                 for i in xrange(blo, bhi):
                     yield ('+', b[i])
 
     def display(fm, fn, ctx, pstates, states):
         rev = ctx.rev()
         if fm.isplain():
             formatuser = ui.shortuser
         else:
             formatuser = str
         if ui.quiet:
             datefmt = '%Y-%m-%d'
         else:
             datefmt = '%a %b %d %H:%M:%S %Y %1%2'
         found = False
         @util.cachefunc
         def binary():
             flog = getfile(fn)
             return util.binary(flog.read(ctx.filenode(fn)))
 
         fieldnamemap = {'filename': 'file', 'linenumber': 'line_number'}
         if opts.get('all'):
             iter = difflinestates(pstates, states)
         else:
             iter = [('', l) for l in states]
         for change, l in iter:
             fm.startitem()
             fm.data(node=fm.hexfunc(ctx.node()))
             cols = [
                 ('filename', fn, True),
                 ('rev', rev, True),
                 ('linenumber', l.linenum, opts.get('line_number')),
             ]
             if opts.get('all'):
                 cols.append(('change', change, True))
             cols.extend([
                 ('user', formatuser(ctx.user()), opts.get('user')),
                 ('date', fm.formatdate(ctx.date(), datefmt), opts.get('date')),
             ])
             lastcol = next(name for name, data, cond in reversed(cols) if cond)
             for name, data, cond in cols:
                 field = fieldnamemap.get(name, name)
                 fm.condwrite(cond, field, '%s', data, label='grep.%s' % name)
                 if cond and name != lastcol:
                     fm.plain(sep, label='grep.sep')
             if not opts.get('files_with_matches'):
                 fm.plain(sep, label='grep.sep')
                 if not opts.get('text') and binary():
                     fm.plain(_(" Binary file matches"))
                 else:
                     displaymatches(fm.nested('texts'), l)
             fm.plain(eol)
             found = True
             if opts.get('files_with_matches'):
                 break
         return found
 
     def displaymatches(fm, l):
         p = 0
         for s, e in l.findpos():
             if p < s:
                 fm.startitem()
                 fm.write('text', '%s', l.line[p:s])
                 fm.data(matched=False)
             fm.startitem()
             fm.write('text', '%s', l.line[s:e], label='grep.match')
             fm.data(matched=True)
             p = e
         if p < len(l.line):
             fm.startitem()
             fm.write('text', '%s', l.line[p:])
             fm.data(matched=False)
         fm.end()
 
     skip = {}
     revfiles = {}
     matchfn = scmutil.match(repo[None], pats, opts)
     found = False
     follow = opts.get('follow')
 
     def prep(ctx, fns):
         rev = ctx.rev()
         pctx = ctx.p1()
         parent = pctx.rev()
         matches.setdefault(rev, {})
         matches.setdefault(parent, {})
         files = revfiles.setdefault(rev, [])
         for fn in fns:
             flog = getfile(fn)
             try:
                 fnode = ctx.filenode(fn)
             except error.LookupError:
                 continue
 
             copied = flog.renamed(fnode)
             copy = follow and copied and copied[0]
             if copy:
                 copies.setdefault(rev, {})[fn] = copy
             if fn in skip:
                 if copy:
                     skip[copy] = True
                 continue
             files.append(fn)
 
             if fn not in matches[rev]:
                 grepbody(fn, rev, flog.read(fnode))
 
             pfn = copy or fn
             if pfn not in matches[parent]:
                 try:
                     fnode = pctx.filenode(pfn)
                     grepbody(pfn, parent, flog.read(fnode))
                 except error.LookupError:
                     pass
 
     fm = ui.formatter('grep', opts)
     for ctx in cmdutil.walkchangerevs(repo, matchfn, opts, prep):
         rev = ctx.rev()
         parent = ctx.p1().rev()
         for fn in sorted(revfiles.get(rev, [])):
             states = matches[rev][fn]
             copy = copies.get(rev, {}).get(fn)
             if fn in skip:
                 if copy:
                     skip[copy] = True
                 continue
             pstates = matches.get(parent, {}).get(copy or fn, [])
             if pstates or states:
                 r = display(fm, fn, ctx, pstates, states)
                 found = found or r
                 if r and not opts.get('all'):
                     skip[fn] = True
                     if copy:
                         skip[copy] = True
         del matches[rev]
         del revfiles[rev]
     fm.end()
 
     return not found
 
 @command('heads',
     [('r', 'rev', '',
      _('show only heads which are descendants of STARTREV'), _('STARTREV')),
     ('t', 'topo', False, _('show topological heads only')),
     ('a', 'active', False, _('show active branchheads only (DEPRECATED)')),
     ('c', 'closed', False, _('show normal and closed branch heads')),
     ] + templateopts,
     _('[-ct] [-r STARTREV] [REV]...'))
 def heads(ui, repo, *branchrevs, **opts):
     """show branch heads
 
     With no arguments, show all open branch heads in the repository.
     Branch heads are changesets that have no descendants on the
     same branch. They are where development generally takes place and
     are the usual targets for update and merge operations.
 
     If one or more REVs are given, only open branch heads on the
     branches associated with the specified changesets are shown. This
     means that you can use :hg:`heads .` to see the heads on the
     currently checked-out branch.
 
     If -c/--closed is specified, also show branch heads marked closed
     (see :hg:`commit --close-branch`).
 
     If STARTREV is specified, only those heads that are descendants of
     STARTREV will be displayed.
 
     If -t/--topo is specified, named branch mechanics will be ignored and only
     topological heads (changesets with no children) will be shown.
 
     Returns 0 if matching heads are found, 1 if not.
     """
 
     start = None
     if 'rev' in opts:
         start = scmutil.revsingle(repo, opts['rev'], None).node()
 
     if opts.get('topo'):
         heads = [repo[h] for h in repo.heads(start)]
     else:
         heads = []
         for branch in repo.branchmap():
             heads += repo.branchheads(branch, start, opts.get('closed'))
         heads = [repo[h] for h in heads]
 
     if branchrevs:
         branches = set(repo[br].branch() for br in branchrevs)
         heads = [h for h in heads if h.branch() in branches]
 
     if opts.get('active') and branchrevs:
         dagheads = repo.heads(start)
         heads = [h for h in heads if h.node() in dagheads]
 
     if branchrevs:
         haveheads = set(h.branch() for h in heads)
         if branches - haveheads:
             headless = ', '.join(b for b in branches - haveheads)
             msg = _('no open branch heads found on branches %s')
             if opts.get('rev'):
                 msg += _(' (started at %s)') % opts['rev']
             ui.warn((msg + '\n') % headless)
 
     if not heads:
         return 1
 
     heads = sorted(heads, key=lambda x: -x.rev())
     displayer = cmdutil.show_changeset(ui, repo, opts)
     for ctx in heads:
         displayer.show(ctx)
     displayer.close()
 
 @command('help',
     [('e', 'extension', None, _('show only help for extensions')),
      ('c', 'command', None, _('show only help for commands')),
      ('k', 'keyword', None, _('show topics matching keyword')),
      ('s', 'system', [], _('show help for specific platform(s)')),
      ],
     _('[-ecks] [TOPIC]'),
     norepo=True)
 def help_(ui, name=None, **opts):
     """show help for a given topic or a help overview
 
     With no arguments, print a list of commands with short help messages.
 
     Given a topic, extension, or command name, print help for that
     topic.
 
     Returns 0 if successful.
     """
 
     textwidth = ui.configint('ui', 'textwidth', 78)
     termwidth = ui.termwidth() - 2
     if textwidth <= 0 or termwidth < textwidth:
         textwidth = termwidth
 
     keep = opts.get('system') or []
     if len(keep) == 0:
         if pycompat.sysplatform.startswith('win'):
             keep.append('windows')
         elif pycompat.sysplatform == 'OpenVMS':
             keep.append('vms')
         elif pycompat.sysplatform == 'plan9':
             keep.append('plan9')
         else:
             keep.append('unix')
             keep.append(pycompat.sysplatform.lower())
     if ui.verbose:
         keep.append('verbose')
 
     section = None
     subtopic = None
     if name and '.' in name:
         name, remaining = name.split('.', 1)
         remaining = encoding.lower(remaining)
         if '.' in remaining:
             subtopic, section = remaining.split('.', 1)
         else:
             if name in help.subtopics:
                 subtopic = remaining
             else:
                 section = remaining
 
     text = help.help_(ui, name, subtopic=subtopic, **opts)
 
     formatted, pruned = minirst.format(text, textwidth, keep=keep,
                                        section=section)
 
     # We could have been given a weird ".foo" section without a name
     # to look for, or we could have simply failed to found "foo.bar"
     # because bar isn't a section of foo
     if section and not (formatted and name):
         raise error.Abort(_("help section not found"))
 
     if 'verbose' in pruned:
         keep.append('omitted')
     else:
         keep.append('notomitted')
     formatted, pruned = minirst.format(text, textwidth, keep=keep,
                                        section=section)
     ui.write(formatted)
 
 
 @command('identify|id',
     [('r', 'rev', '',
      _('identify the specified revision'), _('REV')),
     ('n', 'num', None, _('show local revision number')),
     ('i', 'id', None, _('show global revision id')),
     ('b', 'branch', None, _('show branch')),
     ('t', 'tags', None, _('show tags')),
     ('B', 'bookmarks', None, _('show bookmarks')),
     ] + remoteopts,
     _('[-nibtB] [-r REV] [SOURCE]'),
     optionalrepo=True)
 def identify(ui, repo, source=None, rev=None,
              num=None, id=None, branch=None, tags=None, bookmarks=None, **opts):
     """identify the working directory or specified revision
 
     Print a summary identifying the repository state at REV using one or
     two parent hash identifiers, followed by a "+" if the working
     directory has uncommitted changes, the branch name (if not default),
     a list of tags, and a list of bookmarks.
 
     When REV is not given, print a summary of the current state of the
     repository.
 
     Specifying a path to a repository root or Mercurial bundle will
     cause lookup to operate on that repository/bundle.
 
     .. container:: verbose
 
       Examples:
 
       - generate a build identifier for the working directory::
 
           hg id --id > build-id.dat
 
       - find the revision corresponding to a tag::
 
           hg id -n -r 1.3
 
       - check the most recent revision of a remote repository::
 
           hg id -r tip https://www.mercurial-scm.org/repo/hg/
 
     See :hg:`log` for generating more information about specific revisions,
     including full hash identifiers.
 
     Returns 0 if successful.
     """
 
     if not repo and not source:
         raise error.Abort(_("there is no Mercurial repository here "
                            "(.hg not found)"))
 
     if ui.debugflag:
         hexfunc = hex
     else:
         hexfunc = short
     default = not (num or id or branch or tags or bookmarks)
     output = []
     revs = []
 
     if source:
         source, branches = hg.parseurl(ui.expandpath(source))
         peer = hg.peer(repo or ui, opts, source) # only pass ui when no repo
         repo = peer.local()
         revs, checkout = hg.addbranchrevs(repo, peer, branches, None)
 
     if not repo:
         if num or branch or tags:
             raise error.Abort(
                 _("can't query remote revision number, branch, or tags"))
         if not rev and revs:
             rev = revs[0]
         if not rev:
             rev = "tip"
 
         remoterev = peer.lookup(rev)
         if default or id:
             output = [hexfunc(remoterev)]
 
         def getbms():
             bms = []
 
             if 'bookmarks' in peer.listkeys('namespaces'):
                 hexremoterev = hex(remoterev)
                 bms = [bm for bm, bmr in peer.listkeys('bookmarks').iteritems()
                        if bmr == hexremoterev]
 
             return sorted(bms)
 
         if bookmarks:
             output.extend(getbms())
         elif default and not ui.quiet:
             # multiple bookmarks for a single parent separated by '/'
             bm = '/'.join(getbms())
             if bm:
                 output.append(bm)
     else:
         ctx = scmutil.revsingle(repo, rev, None)
 
         if ctx.rev() is None:
             ctx = repo[None]
             parents = ctx.parents()
             taglist = []
             for p in parents:
                 taglist.extend(p.tags())
 
             changed = ""
             if default or id or num:
                 if (any(repo.status())
                     or any(ctx.sub(s).dirty() for s in ctx.substate)):
                     changed = '+'
             if default or id:
                 output = ["%s%s" %
                   ('+'.join([hexfunc(p.node()) for p in parents]), changed)]
             if num:
                 output.append("%s%s" %
                   ('+'.join([str(p.rev()) for p in parents]), changed))
         else:
             if default or id:
                 output = [hexfunc(ctx.node())]
             if num:
                 output.append(str(ctx.rev()))
             taglist = ctx.tags()
 
         if default and not ui.quiet:
             b = ctx.branch()
             if b != 'default':
                 output.append("(%s)" % b)
 
             # multiple tags for a single parent separated by '/'
             t = '/'.join(taglist)
             if t:
                 output.append(t)
 
             # multiple bookmarks for a single parent separated by '/'
             bm = '/'.join(ctx.bookmarks())
             if bm:
                 output.append(bm)
         else:
             if branch:
                 output.append(ctx.branch())
 
             if tags:
                 output.extend(taglist)
 
             if bookmarks:
                 output.extend(ctx.bookmarks())
 
     ui.write("%s\n" % ' '.join(output))
 
 @command('import|patch',
     [('p', 'strip', 1,
      _('directory strip option for patch. This has the same '
        'meaning as the corresponding patch option'), _('NUM')),
     ('b', 'base', '', _('base path (DEPRECATED)'), _('PATH')),
     ('e', 'edit', False, _('invoke editor on commit messages')),
     ('f', 'force', None,
      _('skip check for outstanding uncommitted changes (DEPRECATED)')),
     ('', 'no-commit', None,
      _("don't commit, just update the working directory")),
     ('', 'bypass', None,
      _("apply patch without touching the working directory")),
     ('', 'partial', None,
      _('commit even if some hunks fail')),
     ('', 'exact', None,
      _('abort if patch would apply lossily')),
     ('', 'prefix', '',
      _('apply patch to subdirectory'), _('DIR')),
     ('', 'import-branch', None,
      _('use any branch information in patch (implied by --exact)'))] +
     commitopts + commitopts2 + similarityopts,
     _('[OPTION]... PATCH...'))
 def import_(ui, repo, patch1=None, *patches, **opts):
     """import an ordered set of patches
 
     Import a list of patches and commit them individually (unless
     --no-commit is specified).
 
     To read a patch from standard input, use "-" as the patch name. If
     a URL is specified, the patch will be downloaded from there.
 
     Import first applies changes to the working directory (unless
     --bypass is specified), import will abort if there are outstanding
     changes.
 
     Use --bypass to apply and commit patches directly to the
     repository, without affecting the working directory. Without
     --exact, patches will be applied on top of the working directory
     parent revision.
 
     You can import a patch straight from a mail message. Even patches
     as attachments work (to use the body part, it must have type
     text/plain or text/x-patch). From and Subject headers of email
     message are used as default committer and commit message. All
     text/plain body parts before first diff are added to the commit
     message.
 
     If the imported patch was generated by :hg:`export`, user and
     description from patch override values from message headers and
     body. Values given on command line with -m/--message and -u/--user
     override these.
 
     If --exact is specified, import will set the working directory to
     the parent of each patch before applying it, and will abort if the
     resulting changeset has a different ID than the one recorded in
     the patch. This will guard against various ways that portable
     patch formats and mail systems might fail to transfer Mercurial
     data or metadata. See :hg:`bundle` for lossless transmission.
 
     Use --partial to ensure a changeset will be created from the patch
     even if some hunks fail to apply. Hunks that fail to apply will be
     written to a <target-file>.rej file. Conflicts can then be resolved
     by hand before :hg:`commit --amend` is run to update the created
     changeset. This flag exists to let people import patches that
     partially apply without losing the associated metadata (author,
     date, description, ...).
 
     .. note::
 
        When no hunks apply cleanly, :hg:`import --partial` will create
        an empty changeset, importing only the patch metadata.
 
     With -s/--similarity, hg will attempt to discover renames and
     copies in the patch in the same way as :hg:`addremove`.
 
     It is possible to use external patch programs to perform the patch
     by setting the ``ui.patch`` configuration option. For the default
     internal tool, the fuzz can also be configured via ``patch.fuzz``.
     See :hg:`help config` for more information about configuration
     files and how to use these options.
 
     See :hg:`help dates` for a list of formats valid for -d/--date.
 
     .. container:: verbose
 
       Examples:
 
       - import a traditional patch from a website and detect renames::
 
           hg import -s 80 http://example.com/bugfix.patch
 
       - import a changeset from an hgweb server::
 
           hg import https://www.mercurial-scm.org/repo/hg/rev/5ca8c111e9aa
 
       - import all the patches in an Unix-style mbox::
 
           hg import incoming-patches.mbox
 
       - attempt to exactly restore an exported changeset (not always
         possible)::
 
           hg import --exact proposed-fix.patch
 
       - use an external tool to apply a patch which is too fuzzy for
         the default internal tool.
 
           hg import --config ui.patch="patch --merge" fuzzy.patch
 
       - change the default fuzzing from 2 to a less strict 7
 
           hg import --config ui.fuzz=7 fuzz.patch
 
     Returns 0 on success, 1 on partial success (see --partial).
     """
 
     if not patch1:
         raise error.Abort(_('need at least one patch to import'))
 
     patches = (patch1,) + patches
 
     date = opts.get('date')
     if date:
         opts['date'] = util.parsedate(date)
 
     exact = opts.get('exact')
     update = not opts.get('bypass')
     if not update and opts.get('no_commit'):
         raise error.Abort(_('cannot use --no-commit with --bypass'))
     try:
         sim = float(opts.get('similarity') or 0)
     except ValueError:
         raise error.Abort(_('similarity must be a number'))
     if sim < 0 or sim > 100:
         raise error.Abort(_('similarity must be between 0 and 100'))
     if sim and not update:
         raise error.Abort(_('cannot use --similarity with --bypass'))
     if exact:
         if opts.get('edit'):
             raise error.Abort(_('cannot use --exact with --edit'))
         if opts.get('prefix'):
             raise error.Abort(_('cannot use --exact with --prefix'))
 
     base = opts["base"]
     wlock = dsguard = lock = tr = None
     msgs = []
     ret = 0
 
 
     try:
         wlock = repo.wlock()
 
         if update:
             cmdutil.checkunfinished(repo)
             if (exact or not opts.get('force')):
                 cmdutil.bailifchanged(repo)
 
         if not opts.get('no_commit'):
             lock = repo.lock()
             tr = repo.transaction('import')
         else:
             dsguard = dirstateguard.dirstateguard(repo, 'import')
         parents = repo[None].parents()
         for patchurl in patches:
             if patchurl == '-':
                 ui.status(_('applying patch from stdin\n'))
                 patchfile = ui.fin
                 patchurl = 'stdin'      # for error message
             else:
                 patchurl = os.path.join(base, patchurl)
                 ui.status(_('applying %s\n') % patchurl)
                 patchfile = hg.openpath(ui, patchurl)
 
             haspatch = False
             for hunk in patch.split(patchfile):
                 (msg, node, rej) = cmdutil.tryimportone(ui, repo, hunk,
                                                         parents, opts,
                                                         msgs, hg.clean)
                 if msg:
                     haspatch = True
                     ui.note(msg + '\n')
                 if update or exact:
                     parents = repo[None].parents()
                 else:
                     parents = [repo[node]]
                 if rej:
                     ui.write_err(_("patch applied partially\n"))
                     ui.write_err(_("(fix the .rej files and run "
                                    "`hg commit --amend`)\n"))
                     ret = 1
                     break
 
             if not haspatch:
                 raise error.Abort(_('%s: no diffs found') % patchurl)
 
         if tr:
             tr.close()
         if msgs:
             repo.savecommitmessage('\n* * *\n'.join(msgs))
         if dsguard:
             dsguard.close()
         return ret
     finally:
         if tr:
             tr.release()
         release(lock, dsguard, wlock)
 
 @command('incoming|in',
     [('f', 'force', None,
      _('run even if remote repository is unrelated')),
     ('n', 'newest-first', None, _('show newest record first')),
     ('', 'bundle', '',
      _('file to store the bundles into'), _('FILE')),
     ('r', 'rev', [], _('a remote changeset intended to be added'), _('REV')),
     ('B', 'bookmarks', False, _("compare bookmarks")),
     ('b', 'branch', [],
      _('a specific branch you would like to pull'), _('BRANCH')),
     ] + logopts + remoteopts + subrepoopts,
     _('[-p] [-n] [-M] [-f] [-r REV]... [--bundle FILENAME] [SOURCE]'))
 def incoming(ui, repo, source="default", **opts):
     """show new changesets found in source
 
     Show new changesets found in the specified path/URL or the default
     pull location. These are the changesets that would have been pulled
     if a pull at the time you issued this command.
 
     See pull for valid source format details.
 
     .. container:: verbose
 
       With -B/--bookmarks, the result of bookmark comparison between
       local and remote repositories is displayed. With -v/--verbose,
       status is also displayed for each bookmark like below::
 
         BM1               01234567890a added
         BM2               1234567890ab advanced
         BM3               234567890abc diverged
         BM4               34567890abcd changed
 
       The action taken locally when pulling depends on the
       status of each bookmark:
 
       :``added``: pull will create it
       :``advanced``: pull will update it
       :``diverged``: pull will create a divergent bookmark
       :``changed``: result depends on remote changesets
 
       From the point of view of pulling behavior, bookmark
       existing only in the remote repository are treated as ``added``,
       even if it is in fact locally deleted.
 
     .. container:: verbose
 
       For remote repository, using --bundle avoids downloading the
       changesets twice if the incoming is followed by a pull.
 
       Examples:
 
       - show incoming changes with patches and full description::
 
           hg incoming -vp
 
       - show incoming changes excluding merges, store a bundle::
 
           hg in -vpM --bundle incoming.hg
           hg pull incoming.hg
 
       - briefly list changes inside a bundle::
 
           hg in changes.hg -T "{desc|firstline}\\n"
 
     Returns 0 if there are incoming changes, 1 otherwise.
     """
     if opts.get('graph'):
         cmdutil.checkunsupportedgraphflags([], opts)
         def display(other, chlist, displayer):
             revdag = cmdutil.graphrevs(other, chlist, opts)
             cmdutil.displaygraph(ui, repo, revdag, displayer,
                                  graphmod.asciiedges)
 
         hg._incoming(display, lambda: 1, ui, repo, source, opts, buffered=True)
         return 0
 
     if opts.get('bundle') and opts.get('subrepos'):
         raise error.Abort(_('cannot combine --bundle and --subrepos'))
 
     if opts.get('bookmarks'):
         source, branches = hg.parseurl(ui.expandpath(source),
                                        opts.get('branch'))
         other = hg.peer(repo, opts, source)
         if 'bookmarks' not in other.listkeys('namespaces'):
             ui.warn(_("remote doesn't support bookmarks\n"))
             return 0
         ui.status(_('comparing with %s\n') % util.hidepassword(source))
         return bookmarks.incoming(ui, repo, other)
 
     repo._subtoppath = ui.expandpath(source)
     try:
         return hg.incoming(ui, repo, source, opts)
     finally:
         del repo._subtoppath
 
 
 @command('^init', remoteopts, _('[-e CMD] [--remotecmd CMD] [DEST]'),
          norepo=True)
 def init(ui, dest=".", **opts):
     """create a new repository in the given directory
 
     Initialize a new repository in the given directory. If the given
     directory does not exist, it will be created.
 
     If no directory is given, the current directory is used.
 
     It is possible to specify an ``ssh://`` URL as the destination.
     See :hg:`help urls` for more information.
 
     Returns 0 on success.
     """
     hg.peer(ui, opts, ui.expandpath(dest), create=True)
 
 @command('locate',
     [('r', 'rev', '', _('search the repository as it is in REV'), _('REV')),
     ('0', 'print0', None, _('end filenames with NUL, for use with xargs')),
     ('f', 'fullpath', None, _('print complete paths from the filesystem root')),
     ] + walkopts,
     _('[OPTION]... [PATTERN]...'))
 def locate(ui, repo, *pats, **opts):
     """locate files matching specific patterns (DEPRECATED)
 
     Print files under Mercurial control in the working directory whose
     names match the given patterns.
 
     By default, this command searches all directories in the working
     directory. To search just the current directory and its
     subdirectories, use "--include .".
 
     If no patterns are given to match, this command prints the names
     of all files under Mercurial control in the working directory.
 
     If you want to feed the output of this command into the "xargs"
     command, use the -0 option to both this command and "xargs". This
     will avoid the problem of "xargs" treating single filenames that
     contain whitespace as multiple filenames.
 
     See :hg:`help files` for a more versatile command.
 
     Returns 0 if a match is found, 1 otherwise.
     """
     if opts.get('print0'):
         end = '\0'
     else:
         end = '\n'
     rev = scmutil.revsingle(repo, opts.get('rev'), None).node()
 
     ret = 1
     ctx = repo[rev]
     m = scmutil.match(ctx, pats, opts, default='relglob',
                       badfn=lambda x, y: False)
 
     for abs in ctx.matches(m):
         if opts.get('fullpath'):
             ui.write(repo.wjoin(abs), end)
         else:
             ui.write(((pats and m.rel(abs)) or abs), end)
         ret = 0
 
     return ret
 
 @command('^log|history',
     [('f', 'follow', None,
      _('follow changeset history, or file history across copies and renames')),
     ('', 'follow-first', None,
      _('only follow the first parent of merge changesets (DEPRECATED)')),
     ('d', 'date', '', _('show revisions matching date spec'), _('DATE')),
     ('C', 'copies', None, _('show copied files')),
     ('k', 'keyword', [],
      _('do case-insensitive search for a given text'), _('TEXT')),
     ('r', 'rev', [], _('show the specified revision or revset'), _('REV')),
     ('', 'removed', None, _('include revisions where files were removed')),
     ('m', 'only-merges', None, _('show only merges (DEPRECATED)')),
     ('u', 'user', [], _('revisions committed by user'), _('USER')),
     ('', 'only-branch', [],
      _('show only changesets within the given named branch (DEPRECATED)'),
      _('BRANCH')),
     ('b', 'branch', [],
      _('show changesets within the given named branch'), _('BRANCH')),
     ('P', 'prune', [],
      _('do not display revision or any of its ancestors'), _('REV')),
     ] + logopts + walkopts,
     _('[OPTION]... [FILE]'),
     inferrepo=True)
 def log(ui, repo, *pats, **opts):
     """show revision history of entire repository or files
 
     Print the revision history of the specified files or the entire
     project.
 
     If no revision range is specified, the default is ``tip:0`` unless
     --follow is set, in which case the working directory parent is
     used as the starting revision.
 
     File history is shown without following rename or copy history of
     files. Use -f/--follow with a filename to follow history across
     renames and copies. --follow without a filename will only show
     ancestors or descendants of the starting revision.
 
     By default this command prints revision number and changeset id,
     tags, non-trivial parents, user, date and time, and a summary for
     each commit. When the -v/--verbose switch is used, the list of
     changed files and full commit message are shown.
 
     With --graph the revisions are shown as an ASCII art DAG with the most
     recent changeset at the top.
     'o' is a changeset, '@' is a working directory parent, 'x' is obsolete,
     and '+' represents a fork where the changeset from the lines below is a
     parent of the 'o' merge on the same line.
 
     .. note::
 
        :hg:`log --patch` may generate unexpected diff output for merge
        changesets, as it will only compare the merge changeset against
        its first parent. Also, only files different from BOTH parents
        will appear in files:.
 
     .. note::
 
        For performance reasons, :hg:`log FILE` may omit duplicate changes
        made on branches and will not show removals or mode changes. To
        see all such changes, use the --removed switch.
 
     .. container:: verbose
 
       Some examples:
 
       - changesets with full descriptions and file lists::
 
           hg log -v
 
       - changesets ancestral to the working directory::
 
           hg log -f
 
       - last 10 commits on the current branch::
 
           hg log -l 10 -b .
 
       - changesets showing all modifications of a file, including removals::
 
           hg log --removed file.c
 
       - all changesets that touch a directory, with diffs, excluding merges::
 
           hg log -Mp lib/
 
       - all revision numbers that match a keyword::
 
           hg log -k bug --template "{rev}\\n"
 
       - the full hash identifier of the working directory parent::
 
           hg log -r . --template "{node}\\n"
 
       - list available log templates::
 
           hg log -T list
 
       - check if a given changeset is included in a tagged release::
 
           hg log -r "a21ccf and ancestor(1.9)"
 
       - find all changesets by some user in a date range::
 
           hg log -k alice -d "may 2008 to jul 2008"
 
       - summary of all changesets after the last tag::
 
           hg log -r "last(tagged())::" --template "{desc|firstline}\\n"
 
     See :hg:`help dates` for a list of formats valid for -d/--date.
 
     See :hg:`help revisions` and :hg:`help revsets` for more about
     specifying and ordering revisions.
 
     See :hg:`help templates` for more about pre-packaged styles and
     specifying custom templates.
 
     Returns 0 on success.
 
     """
     if opts.get('follow') and opts.get('rev'):
         opts['rev'] = [revset.formatspec('reverse(::%lr)', opts.get('rev'))]
         del opts['follow']
 
     if opts.get('graph'):
         return cmdutil.graphlog(ui, repo, *pats, **opts)
 
     revs, expr, filematcher = cmdutil.getlogrevs(repo, pats, opts)
     limit = cmdutil.loglimit(opts)
     count = 0
 
     getrenamed = None
     if opts.get('copies'):
         endrev = None
         if opts.get('rev'):
             endrev = scmutil.revrange(repo, opts.get('rev')).max() + 1
         getrenamed = templatekw.getrenamedfn(repo, endrev=endrev)
 
     displayer = cmdutil.show_changeset(ui, repo, opts, buffered=True)
     for rev in revs:
         if count == limit:
             break
         ctx = repo[rev]
         copies = None
         if getrenamed is not None and rev:
             copies = []
             for fn in ctx.files():
                 rename = getrenamed(fn, rev)
                 if rename:
                     copies.append((fn, rename[0]))
         if filematcher:
             revmatchfn = filematcher(ctx.rev())
         else:
             revmatchfn = None
         displayer.show(ctx, copies=copies, matchfn=revmatchfn)
         if displayer.flush(ctx):
             count += 1
 
     displayer.close()
 
 @command('manifest',
     [('r', 'rev', '', _('revision to display'), _('REV')),
      ('', 'all', False, _("list files from all revisions"))]
          + formatteropts,
     _('[-r REV]'))
 def manifest(ui, repo, node=None, rev=None, **opts):
     """output the current or given revision of the project manifest
 
     Print a list of version controlled files for the given revision.
     If no revision is given, the first parent of the working directory
     is used, or the null revision if no revision is checked out.
 
     With -v, print file permissions, symlink and executable bits.
     With --debug, print file revision hashes.
 
     If option --all is specified, the list of all files from all revisions
     is printed. This includes deleted and renamed files.
 
     Returns 0 on success.
     """
 
     fm = ui.formatter('manifest', opts)
 
     if opts.get('all'):
         if rev or node:
             raise error.Abort(_("can't specify a revision with --all"))
 
         res = []
         prefix = "data/"
         suffix = ".i"
         plen = len(prefix)
         slen = len(suffix)
         with repo.lock():
             for fn, b, size in repo.store.datafiles():
                 if size != 0 and fn[-slen:] == suffix and fn[:plen] == prefix:
                     res.append(fn[plen:-slen])
         for f in res:
             fm.startitem()
             fm.write("path", '%s\n', f)
         fm.end()
         return
 
     if rev and node:
         raise error.Abort(_("please specify just one revision"))
 
     if not node:
         node = rev
 
     char = {'l': '@', 'x': '*', '': ''}
     mode = {'l': '644', 'x': '755', '': '644'}
     ctx = scmutil.revsingle(repo, node)
     mf = ctx.manifest()
     for f in ctx:
         fm.startitem()
         fl = ctx[f].flags()
         fm.condwrite(ui.debugflag, 'hash', '%s ', hex(mf[f]))
         fm.condwrite(ui.verbose, 'mode type', '%s %1s ', mode[fl], char[fl])
         fm.write('path', '%s\n', f)
     fm.end()
 
 @command('^merge',
     [('f', 'force', None,
       _('force a merge including outstanding changes (DEPRECATED)')),
     ('r', 'rev', '', _('revision to merge'), _('REV')),
     ('P', 'preview', None,
      _('review revisions to merge (no merge is performed)'))
      ] + mergetoolopts,
     _('[-P] [[-r] REV]'))
 def merge(ui, repo, node=None, **opts):
     """merge another revision into working directory
 
     The current working directory is updated with all changes made in
     the requested revision since the last common predecessor revision.
 
     Files that changed between either parent are marked as changed for
     the next commit and a commit must be performed before any further
     updates to the repository are allowed. The next commit will have
     two parents.
 
     ``--tool`` can be used to specify the merge tool used for file
     merges. It overrides the HGMERGE environment variable and your
     configuration files. See :hg:`help merge-tools` for options.
 
     If no revision is specified, the working directory's parent is a
     head revision, and the current branch contains exactly one other
     head, the other head is merged with by default. Otherwise, an
     explicit revision with which to merge with must be provided.
 
     See :hg:`help resolve` for information on handling file conflicts.
 
     To undo an uncommitted merge, use :hg:`update --clean .` which
     will check out a clean copy of the original merge parent, losing
     all changes.
 
     Returns 0 on success, 1 if there are unresolved files.
     """
 
     if opts.get('rev') and node:
         raise error.Abort(_("please specify just one revision"))
     if not node:
         node = opts.get('rev')
 
     if node:
         node = scmutil.revsingle(repo, node).node()
 
     if not node:
         node = repo[destutil.destmerge(repo)].node()
 
     if opts.get('preview'):
         # find nodes that are ancestors of p2 but not of p1
         p1 = repo.lookup('.')
         p2 = repo.lookup(node)
         nodes = repo.changelog.findmissing(common=[p1], heads=[p2])
 
         displayer = cmdutil.show_changeset(ui, repo, opts)
         for node in nodes:
             displayer.show(repo[node])
         displayer.close()
         return 0
 
     try:
         # ui.forcemerge is an internal variable, do not document
         repo.ui.setconfig('ui', 'forcemerge', opts.get('tool', ''), 'merge')
         force = opts.get('force')
         labels = ['working copy', 'merge rev']
         return hg.merge(repo, node, force=force, mergeforce=force,
                         labels=labels)
     finally:
         ui.setconfig('ui', 'forcemerge', '', 'merge')
 
 @command('outgoing|out',
     [('f', 'force', None, _('run even when the destination is unrelated')),
     ('r', 'rev', [],
      _('a changeset intended to be included in the destination'), _('REV')),
     ('n', 'newest-first', None, _('show newest record first')),
     ('B', 'bookmarks', False, _('compare bookmarks')),
     ('b', 'branch', [], _('a specific branch you would like to push'),
      _('BRANCH')),
     ] + logopts + remoteopts + subrepoopts,
     _('[-M] [-p] [-n] [-f] [-r REV]... [DEST]'))
 def outgoing(ui, repo, dest=None, **opts):
     """show changesets not found in the destination
 
     Show changesets not found in the specified destination repository
     or the default push location. These are the changesets that would
     be pushed if a push was requested.
 
     See pull for details of valid destination formats.
 
     .. container:: verbose
 
       With -B/--bookmarks, the result of bookmark comparison between
       local and remote repositories is displayed. With -v/--verbose,
       status is also displayed for each bookmark like below::
 
         BM1               01234567890a added
         BM2                            deleted
         BM3               234567890abc advanced
         BM4               34567890abcd diverged
         BM5               4567890abcde changed
 
       The action taken when pushing depends on the
       status of each bookmark:
 
       :``added``: push with ``-B`` will create it
       :``deleted``: push with ``-B`` will delete it
       :``advanced``: push will update it
       :``diverged``: push with ``-B`` will update it
       :``changed``: push with ``-B`` will update it
 
       From the point of view of pushing behavior, bookmarks
       existing only in the remote repository are treated as
       ``deleted``, even if it is in fact added remotely.
 
     Returns 0 if there are outgoing changes, 1 otherwise.
     """
     if opts.get('graph'):
         cmdutil.checkunsupportedgraphflags([], opts)
         o, other = hg._outgoing(ui, repo, dest, opts)
         if not o:
             cmdutil.outgoinghooks(ui, repo, other, opts, o)
             return
 
         revdag = cmdutil.graphrevs(repo, o, opts)
         displayer = cmdutil.show_changeset(ui, repo, opts, buffered=True)
         cmdutil.displaygraph(ui, repo, revdag, displayer, graphmod.asciiedges)
         cmdutil.outgoinghooks(ui, repo, other, opts, o)
         return 0
 
     if opts.get('bookmarks'):
         dest = ui.expandpath(dest or 'default-push', dest or 'default')
         dest, branches = hg.parseurl(dest, opts.get('branch'))
         other = hg.peer(repo, opts, dest)
         if 'bookmarks' not in other.listkeys('namespaces'):
             ui.warn(_("remote doesn't support bookmarks\n"))
             return 0
         ui.status(_('comparing with %s\n') % util.hidepassword(dest))
         return bookmarks.outgoing(ui, repo, other)
 
     repo._subtoppath = ui.expandpath(dest or 'default-push', dest or 'default')
     try:
         return hg.outgoing(ui, repo, dest, opts)
     finally:
         del repo._subtoppath
 
 @command('parents',
     [('r', 'rev', '', _('show parents of the specified revision'), _('REV')),
     ] + templateopts,
     _('[-r REV] [FILE]'),
     inferrepo=True)
 def parents(ui, repo, file_=None, **opts):
     """show the parents of the working directory or revision (DEPRECATED)
 
     Print the working directory's parent revisions. If a revision is
     given via -r/--rev, the parent of that revision will be printed.
     If a file argument is given, the revision in which the file was
     last changed (before the working directory revision or the
     argument to --rev if given) is printed.
 
     This command is equivalent to::
 
         hg log -r "p1()+p2()" or
         hg log -r "p1(REV)+p2(REV)" or
         hg log -r "max(::p1() and file(FILE))+max(::p2() and file(FILE))" or
         hg log -r "max(::p1(REV) and file(FILE))+max(::p2(REV) and file(FILE))"
 
     See :hg:`summary` and :hg:`help revsets` for related information.
 
     Returns 0 on success.
     """
 
     ctx = scmutil.revsingle(repo, opts.get('rev'), None)
 
     if file_:
         m = scmutil.match(ctx, (file_,), opts)
         if m.anypats() or len(m.files()) != 1:
             raise error.Abort(_('can only specify an explicit filename'))
         file_ = m.files()[0]
         filenodes = []
         for cp in ctx.parents():
             if not cp:
                 continue
             try:
                 filenodes.append(cp.filenode(file_))
             except error.LookupError:
                 pass
         if not filenodes:
             raise error.Abort(_("'%s' not found in manifest!") % file_)
         p = []
         for fn in filenodes:
             fctx = repo.filectx(file_, fileid=fn)
             p.append(fctx.node())
     else:
         p = [cp.node() for cp in ctx.parents()]
 
     displayer = cmdutil.show_changeset(ui, repo, opts)
     for n in p:
         if n != nullid:
             displayer.show(repo[n])
     displayer.close()
 
 @command('paths', formatteropts, _('[NAME]'), optionalrepo=True)
 def paths(ui, repo, search=None, **opts):
     """show aliases for remote repositories
 
     Show definition of symbolic path name NAME. If no name is given,
     show definition of all available names.
 
     Option -q/--quiet suppresses all output when searching for NAME
     and shows only the path names when listing all definitions.
 
     Path names are defined in the [paths] section of your
     configuration file and in ``/etc/mercurial/hgrc``. If run inside a
     repository, ``.hg/hgrc`` is used, too.
 
     The path names ``default`` and ``default-push`` have a special
     meaning.  When performing a push or pull operation, they are used
     as fallbacks if no location is specified on the command-line.
     When ``default-push`` is set, it will be used for push and
     ``default`` will be used for pull; otherwise ``default`` is used
     as the fallback for both.  When cloning a repository, the clone
     source is written as ``default`` in ``.hg/hgrc``.
 
     .. note::
 
        ``default`` and ``default-push`` apply to all inbound (e.g.
        :hg:`incoming`) and outbound (e.g. :hg:`outgoing`, :hg:`email`
        and :hg:`bundle`) operations.
 
     See :hg:`help urls` for more information.
 
     Returns 0 on success.
     """
     if search:
         pathitems = [(name, path) for name, path in ui.paths.iteritems()
                      if name == search]
     else:
         pathitems = sorted(ui.paths.iteritems())
 
     fm = ui.formatter('paths', opts)
     if fm.isplain():
         hidepassword = util.hidepassword
     else:
         hidepassword = str
     if ui.quiet:
         namefmt = '%s\n'
     else:
         namefmt = '%s = '
     showsubopts = not search and not ui.quiet
 
     for name, path in pathitems:
         fm.startitem()
         fm.condwrite(not search, 'name', namefmt, name)
         fm.condwrite(not ui.quiet, 'url', '%s\n', hidepassword(path.rawloc))
         for subopt, value in sorted(path.suboptions.items()):
             assert subopt not in ('name', 'url')
             if showsubopts:
                 fm.plain('%s:%s = ' % (name, subopt))
             fm.condwrite(showsubopts, subopt, '%s\n', value)
 
     fm.end()
 
     if search and not pathitems:
         if not ui.quiet:
             ui.warn(_("not found!\n"))
         return 1
     else:
         return 0
 
 @command('phase',
     [('p', 'public', False, _('set changeset phase to public')),
      ('d', 'draft', False, _('set changeset phase to draft')),
      ('s', 'secret', False, _('set changeset phase to secret')),
      ('f', 'force', False, _('allow to move boundary backward')),
      ('r', 'rev', [], _('target revision'), _('REV')),
     ],
     _('[-p|-d|-s] [-f] [-r] [REV...]'))
 def phase(ui, repo, *revs, **opts):
     """set or show the current phase name
 
     With no argument, show the phase name of the current revision(s).
 
     With one of -p/--public, -d/--draft or -s/--secret, change the
     phase value of the specified revisions.
 
     Unless -f/--force is specified, :hg:`phase` won't move changeset from a
     lower phase to an higher phase. Phases are ordered as follows::
 
         public < draft < secret
 
     Returns 0 on success, 1 if some phases could not be changed.
 
     (For more information about the phases concept, see :hg:`help phases`.)
     """
     # search for a unique phase argument
     targetphase = None
     for idx, name in enumerate(phases.phasenames):
         if opts[name]:
             if targetphase is not None:
                 raise error.Abort(_('only one phase can be specified'))
             targetphase = idx
 
     # look for specified revision
     revs = list(revs)
     revs.extend(opts['rev'])
     if not revs:
         # display both parents as the second parent phase can influence
         # the phase of a merge commit
         revs = [c.rev() for c in repo[None].parents()]
 
     revs = scmutil.revrange(repo, revs)
 
     lock = None
     ret = 0
     if targetphase is None:
         # display
         for r in revs:
             ctx = repo[r]
             ui.write('%i: %s\n' % (ctx.rev(), ctx.phasestr()))
     else:
         tr = None
         lock = repo.lock()
         try:
             tr = repo.transaction("phase")
             # set phase
             if not revs:
                 raise error.Abort(_('empty revision set'))
             nodes = [repo[r].node() for r in revs]
             # moving revision from public to draft may hide them
             # We have to check result on an unfiltered repository
             unfi = repo.unfiltered()
             getphase = unfi._phasecache.phase
             olddata = [getphase(unfi, r) for r in unfi]
             phases.advanceboundary(repo, tr, targetphase, nodes)
             if opts['force']:
                 phases.retractboundary(repo, tr, targetphase, nodes)
             tr.close()
         finally:
             if tr is not None:
                 tr.release()
             lock.release()
         getphase = unfi._phasecache.phase
         newdata = [getphase(unfi, r) for r in unfi]
         changes = sum(newdata[r] != olddata[r] for r in unfi)
         cl = unfi.changelog
         rejected = [n for n in nodes
                     if newdata[cl.rev(n)] < targetphase]
         if rejected:
             ui.warn(_('cannot move %i changesets to a higher '
                       'phase, use --force\n') % len(rejected))
             ret = 1
         if changes:
             msg = _('phase changed for %i changesets\n') % changes
             if ret:
                 ui.status(msg)
             else:
                 ui.note(msg)
         else:
             ui.warn(_('no phases changed\n'))
     return ret
 
 def postincoming(ui, repo, modheads, optupdate, checkout, brev):
     """Run after a changegroup has been added via pull/unbundle
 
     This takes arguments below:
 
     :modheads: change of heads by pull/unbundle
     :optupdate: updating working directory is needed or not
     :checkout: update destination revision (or None to default destination)
     :brev: a name, which might be a bookmark to be activated after updating
     """
     if modheads == 0:
         return
     if optupdate:
         try:
             return hg.updatetotally(ui, repo, checkout, brev)
         except error.UpdateAbort as inst:
             msg = _("not updating: %s") % str(inst)
             hint = inst.hint
             raise error.UpdateAbort(msg, hint=hint)
     if modheads > 1:
         currentbranchheads = len(repo.branchheads())
         if currentbranchheads == modheads:
             ui.status(_("(run 'hg heads' to see heads, 'hg merge' to merge)\n"))
         elif currentbranchheads > 1:
             ui.status(_("(run 'hg heads .' to see heads, 'hg merge' to "
                         "merge)\n"))
         else:
             ui.status(_("(run 'hg heads' to see heads)\n"))
     else:
         ui.status(_("(run 'hg update' to get a working copy)\n"))
 
 @command('^pull',
     [('u', 'update', None,
      _('update to new branch head if changesets were pulled')),
     ('f', 'force', None, _('run even when remote repository is unrelated')),
     ('r', 'rev', [], _('a remote changeset intended to be added'), _('REV')),
     ('B', 'bookmark', [], _("bookmark to pull"), _('BOOKMARK')),
     ('b', 'branch', [], _('a specific branch you would like to pull'),
      _('BRANCH')),
     ] + remoteopts,
     _('[-u] [-f] [-r REV]... [-e CMD] [--remotecmd CMD] [SOURCE]'))
 def pull(ui, repo, source="default", **opts):
     """pull changes from the specified source
 
     Pull changes from a remote repository to a local one.
 
     This finds all changes from the repository at the specified path
     or URL and adds them to a local repository (the current one unless
     -R is specified). By default, this does not update the copy of the
     project in the working directory.
 
     Use :hg:`incoming` if you want to see what would have been added
     by a pull at the time you issued this command. If you then decide
     to add those changes to the repository, you should use :hg:`pull
     -r X` where ``X`` is the last changeset listed by :hg:`incoming`.
 
     If SOURCE is omitted, the 'default' path will be used.
     See :hg:`help urls` for more information.
 
     Specifying bookmark as ``.`` is equivalent to specifying the active
     bookmark's name.
 
     Returns 0 on success, 1 if an update had unresolved files.
     """
     source, branches = hg.parseurl(ui.expandpath(source), opts.get('branch'))
     ui.status(_('pulling from %s\n') % util.hidepassword(source))
     other = hg.peer(repo, opts, source)
     try:
         revs, checkout = hg.addbranchrevs(repo, other, branches,
                                           opts.get('rev'))
 
 
         pullopargs = {}
         if opts.get('bookmark'):
             if not revs:
                 revs = []
             # The list of bookmark used here is not the one used to actually
             # update the bookmark name. This can result in the revision pulled
             # not ending up with the name of the bookmark because of a race
             # condition on the server. (See issue 4689 for details)
             remotebookmarks = other.listkeys('bookmarks')
             pullopargs['remotebookmarks'] = remotebookmarks
             for b in opts['bookmark']:
                 b = repo._bookmarks.expandname(b)
                 if b not in remotebookmarks:
                     raise error.Abort(_('remote bookmark %s not found!') % b)
                 revs.append(remotebookmarks[b])
 
         if revs:
             try:
                 # When 'rev' is a bookmark name, we cannot guarantee that it
                 # will be updated with that name because of a race condition
                 # server side. (See issue 4689 for details)
                 oldrevs = revs
                 revs = [] # actually, nodes
                 for r in oldrevs:
                     node = other.lookup(r)
                     revs.append(node)
                     if r == checkout:
                         checkout = node
             except error.CapabilityError:
                 err = _("other repository doesn't support revision lookup, "
                         "so a rev cannot be specified.")
                 raise error.Abort(err)
 
         pullopargs.update(opts.get('opargs', {}))
         modheads = exchange.pull(repo, other, heads=revs,
                                  force=opts.get('force'),
                                  bookmarks=opts.get('bookmark', ()),
                                  opargs=pullopargs).cgresult
 
         # brev is a name, which might be a bookmark to be activated at
         # the end of the update. In other words, it is an explicit
         # destination of the update
         brev = None
 
         if checkout:
             checkout = str(repo.changelog.rev(checkout))
 
             # order below depends on implementation of
             # hg.addbranchrevs(). opts['bookmark'] is ignored,
             # because 'checkout' is determined without it.
             if opts.get('rev'):
                 brev = opts['rev'][0]
             elif opts.get('branch'):
                 brev = opts['branch'][0]
             else:
                 brev = branches[0]
         repo._subtoppath = source
         try:
             ret = postincoming(ui, repo, modheads, opts.get('update'),
                                checkout, brev)
 
         finally:
             del repo._subtoppath
 
     finally:
         other.close()
     return ret
 
 @command('^push',
     [('f', 'force', None, _('force push')),
     ('r', 'rev', [],
      _('a changeset intended to be included in the destination'),
      _('REV')),
     ('B', 'bookmark', [], _("bookmark to push"), _('BOOKMARK')),
     ('b', 'branch', [],
      _('a specific branch you would like to push'), _('BRANCH')),
     ('', 'new-branch', False, _('allow pushing a new branch')),
     ] + remoteopts,
     _('[-f] [-r REV]... [-e CMD] [--remotecmd CMD] [DEST]'))
 def push(ui, repo, dest=None, **opts):
     """push changes to the specified destination
 
     Push changesets from the local repository to the specified
     destination.
 
     This operation is symmetrical to pull: it is identical to a pull
     in the destination repository from the current one.
 
     By default, push will not allow creation of new heads at the
     destination, since multiple heads would make it unclear which head
     to use. In this situation, it is recommended to pull and merge
     before pushing.
 
     Use --new-branch if you want to allow push to create a new named
     branch that is not present at the destination. This allows you to
     only create a new branch without forcing other changes.
 
     .. note::
 
        Extra care should be taken with the -f/--force option,
        which will push all new heads on all branches, an action which will
        almost always cause confusion for collaborators.
 
     If -r/--rev is used, the specified revision and all its ancestors
     will be pushed to the remote repository.
 
     If -B/--bookmark is used, the specified bookmarked revision, its
     ancestors, and the bookmark will be pushed to the remote
     repository. Specifying ``.`` is equivalent to specifying the active
     bookmark's name.
 
     Please see :hg:`help urls` for important details about ``ssh://``
     URLs. If DESTINATION is omitted, a default path will be used.
 
     Returns 0 if push was successful, 1 if nothing to push.
     """
 
     if opts.get('bookmark'):
         ui.setconfig('bookmarks', 'pushing', opts['bookmark'], 'push')
         for b in opts['bookmark']:
             # translate -B options to -r so changesets get pushed
             b = repo._bookmarks.expandname(b)
             if b in repo._bookmarks:
                 opts.setdefault('rev', []).append(b)
             else:
                 # if we try to push a deleted bookmark, translate it to null
                 # this lets simultaneous -r, -b options continue working
                 opts.setdefault('rev', []).append("null")
 
     path = ui.paths.getpath(dest, default=('default-push', 'default'))
     if not path:
         raise error.Abort(_('default repository not configured!'),
                          hint=_("see 'hg help config.paths'"))
     dest = path.pushloc or path.loc
     branches = (path.branch, opts.get('branch') or [])
     ui.status(_('pushing to %s\n') % util.hidepassword(dest))
     revs, checkout = hg.addbranchrevs(repo, repo, branches, opts.get('rev'))
     other = hg.peer(repo, opts, dest)
 
     if revs:
         revs = [repo.lookup(r) for r in scmutil.revrange(repo, revs)]
         if not revs:
             raise error.Abort(_("specified revisions evaluate to an empty set"),
                              hint=_("use different revision arguments"))
     elif path.pushrev:
         # It doesn't make any sense to specify ancestor revisions. So limit
         # to DAG heads to make discovery simpler.
         expr = revset.formatspec('heads(%r)', path.pushrev)
         revs = scmutil.revrange(repo, [expr])
         revs = [repo[rev].node() for rev in revs]
         if not revs:
             raise error.Abort(_('default push revset for path evaluates to an '
                                 'empty set'))
 
     repo._subtoppath = dest
     try:
         # push subrepos depth-first for coherent ordering
         c = repo['']
         subs = c.substate # only repos that are committed
         for s in sorted(subs):
             result = c.sub(s).push(opts)
             if result == 0:
                 return not result
     finally:
         del repo._subtoppath
     pushop = exchange.push(repo, other, opts.get('force'), revs=revs,
                            newbranch=opts.get('new_branch'),
                            bookmarks=opts.get('bookmark', ()),
                            opargs=opts.get('opargs'))
 
     result = not pushop.cgresult
 
     if pushop.bkresult is not None:
         if pushop.bkresult == 2:
             result = 2
         elif not result and pushop.bkresult:
             result = 2
 
     return result
 
 @command('recover', [])
 def recover(ui, repo):
     """roll back an interrupted transaction
 
     Recover from an interrupted commit or pull.
 
     This command tries to fix the repository status after an
     interrupted operation. It should only be necessary when Mercurial
     suggests it.
 
     Returns 0 if successful, 1 if nothing to recover or verify fails.
     """
     if repo.recover():
         return hg.verify(repo)
     return 1
 
 @command('^remove|rm',
     [('A', 'after', None, _('record delete for missing files')),
     ('f', 'force', None,
      _('forget added files, delete modified files')),
     ] + subrepoopts + walkopts,
     _('[OPTION]... FILE...'),
     inferrepo=True)
 def remove(ui, repo, *pats, **opts):
     """remove the specified files on the next commit
 
     Schedule the indicated files for removal from the current branch.
 
     This command schedules the files to be removed at the next commit.
     To undo a remove before that, see :hg:`revert`. To undo added
     files, see :hg:`forget`.
 
     .. container:: verbose
 
       -A/--after can be used to remove only files that have already
       been deleted, -f/--force can be used to force deletion, and -Af
       can be used to remove files from the next revision without
       deleting them from the working directory.
 
       The following table details the behavior of remove for different
       file states (columns) and option combinations (rows). The file
       states are Added [A], Clean [C], Modified [M] and Missing [!]
       (as reported by :hg:`status`). The actions are Warn, Remove
       (from branch) and Delete (from disk):
 
       ========= == == == ==
       opt/state A  C  M  !
       ========= == == == ==
       none      W  RD W  R
       -f        R  RD RD R
       -A        W  W  W  R
       -Af       R  R  R  R
       ========= == == == ==
 
       .. note::
 
          :hg:`remove` never deletes files in Added [A] state from the
          working directory, not even if ``--force`` is specified.
 
     Returns 0 on success, 1 if any warnings encountered.
     """
 
     after, force = opts.get('after'), opts.get('force')
     if not pats and not after:
         raise error.Abort(_('no files specified'))
 
     m = scmutil.match(repo[None], pats, opts)
     subrepos = opts.get('subrepos')
     return cmdutil.remove(ui, repo, m, "", after, force, subrepos)
 
 @command('rename|move|mv',
     [('A', 'after', None, _('record a rename that has already occurred')),
     ('f', 'force', None, _('forcibly copy over an existing managed file')),
     ] + walkopts + dryrunopts,
     _('[OPTION]... SOURCE... DEST'))
 def rename(ui, repo, *pats, **opts):
     """rename files; equivalent of copy + remove
 
     Mark dest as copies of sources; mark sources for deletion. If dest
     is a directory, copies are put in that directory. If dest is a
     file, there can only be one source.
 
     By default, this command copies the contents of files as they
     exist in the working directory. If invoked with -A/--after, the
     operation is recorded, but no copying is performed.
 
     This command takes effect at the next commit. To undo a rename
     before that, see :hg:`revert`.
 
     Returns 0 on success, 1 if errors are encountered.
     """
     with repo.wlock(False):
         return cmdutil.copy(ui, repo, pats, opts, rename=True)
 
 @command('resolve',
     [('a', 'all', None, _('select all unresolved files')),
     ('l', 'list', None, _('list state of files needing merge')),
     ('m', 'mark', None, _('mark files as resolved')),
     ('u', 'unmark', None, _('mark files as unresolved')),
     ('n', 'no-status', None, _('hide status prefix'))]
     + mergetoolopts + walkopts + formatteropts,
     _('[OPTION]... [FILE]...'),
     inferrepo=True)
 def resolve(ui, repo, *pats, **opts):
     """redo merges or set/view the merge status of files
 
     Merges with unresolved conflicts are often the result of
     non-interactive merging using the ``internal:merge`` configuration
     setting, or a command-line merge tool like ``diff3``. The resolve
     command is used to manage the files involved in a merge, after
     :hg:`merge` has been run, and before :hg:`commit` is run (i.e. the
     working directory must have two parents). See :hg:`help
     merge-tools` for information on configuring merge tools.
 
     The resolve command can be used in the following ways:
 
     - :hg:`resolve [--tool TOOL] FILE...`: attempt to re-merge the specified
       files, discarding any previous merge attempts. Re-merging is not
       performed for files already marked as resolved. Use ``--all/-a``
       to select all unresolved files. ``--tool`` can be used to specify
       the merge tool used for the given files. It overrides the HGMERGE
       environment variable and your configuration files.  Previous file
       contents are saved with a ``.orig`` suffix.
 
     - :hg:`resolve -m [FILE]`: mark a file as having been resolved
       (e.g. after having manually fixed-up the files). The default is
       to mark all unresolved files.
 
     - :hg:`resolve -u [FILE]...`: mark a file as unresolved. The
       default is to mark all resolved files.
 
     - :hg:`resolve -l`: list files which had or still have conflicts.
       In the printed list, ``U`` = unresolved and ``R`` = resolved.
 
     .. note::
 
        Mercurial will not let you commit files with unresolved merge
        conflicts. You must use :hg:`resolve -m ...` before you can
        commit after a conflicting merge.
 
     Returns 0 on success, 1 if any files fail a resolve attempt.
     """
 
     flaglist = 'all mark unmark list no_status'.split()
     all, mark, unmark, show, nostatus = \
         [opts.get(o) for o in flaglist]
 
     if (show and (mark or unmark)) or (mark and unmark):
         raise error.Abort(_("too many options specified"))
     if pats and all:
         raise error.Abort(_("can't specify --all and patterns"))
     if not (all or pats or show or mark or unmark):
         raise error.Abort(_('no files or directories specified'),
                          hint=('use --all to re-merge all unresolved files'))
 
     if show:
         fm = ui.formatter('resolve', opts)
         ms = mergemod.mergestate.read(repo)
         m = scmutil.match(repo[None], pats, opts)
         for f in ms:
             if not m(f):
                 continue
             l = 'resolve.' + {'u': 'unresolved', 'r': 'resolved',
                               'd': 'driverresolved'}[ms[f]]
             fm.startitem()
             fm.condwrite(not nostatus, 'status', '%s ', ms[f].upper(), label=l)
             fm.write('path', '%s\n', f, label=l)
         fm.end()
         return 0
 
     with repo.wlock():
         ms = mergemod.mergestate.read(repo)
 
         if not (ms.active() or repo.dirstate.p2() != nullid):
             raise error.Abort(
                 _('resolve command not applicable when not merging'))
 
         wctx = repo[None]
 
         if ms.mergedriver and ms.mdstate() == 'u':
             proceed = mergemod.driverpreprocess(repo, ms, wctx)
             ms.commit()
             # allow mark and unmark to go through
             if not mark and not unmark and not proceed:
                 return 1
 
         m = scmutil.match(wctx, pats, opts)
         ret = 0
         didwork = False
         runconclude = False
 
         tocomplete = []
         for f in ms:
             if not m(f):
                 continue
 
             didwork = True
 
             # don't let driver-resolved files be marked, and run the conclude
             # step if asked to resolve
             if ms[f] == "d":
                 exact = m.exact(f)
                 if mark:
                     if exact:
                         ui.warn(_('not marking %s as it is driver-resolved\n')
                                 % f)
                 elif unmark:
                     if exact:
                         ui.warn(_('not unmarking %s as it is driver-resolved\n')
                                 % f)
                 else:
                     runconclude = True
                 continue
 
             if mark:
                 ms.mark(f, "r")
             elif unmark:
                 ms.mark(f, "u")
             else:
                 # backup pre-resolve (merge uses .orig for its own purposes)
                 a = repo.wjoin(f)
                 try:
                     util.copyfile(a, a + ".resolve")
                 except (IOError, OSError) as inst:
                     if inst.errno != errno.ENOENT:
                         raise
 
                 try:
                     # preresolve file
                     ui.setconfig('ui', 'forcemerge', opts.get('tool', ''),
                                  'resolve')
                     complete, r = ms.preresolve(f, wctx)
                     if not complete:
                         tocomplete.append(f)
                     elif r:
                         ret = 1
                 finally:
                     ui.setconfig('ui', 'forcemerge', '', 'resolve')
                     ms.commit()
 
                 # replace filemerge's .orig file with our resolve file, but only
                 # for merges that are complete
                 if complete:
                     try:
                         util.rename(a + ".resolve",
                                     scmutil.origpath(ui, repo, a))
                     except OSError as inst:
                         if inst.errno != errno.ENOENT:
                             raise
 
         for f in tocomplete:
             try:
                 # resolve file
                 ui.setconfig('ui', 'forcemerge', opts.get('tool', ''),
                              'resolve')
                 r = ms.resolve(f, wctx)
                 if r:
                     ret = 1
             finally:
                 ui.setconfig('ui', 'forcemerge', '', 'resolve')
                 ms.commit()
 
             # replace filemerge's .orig file with our resolve file
             a = repo.wjoin(f)
             try:
                 util.rename(a + ".resolve", scmutil.origpath(ui, repo, a))
             except OSError as inst:
                 if inst.errno != errno.ENOENT:
                     raise
 
         ms.commit()
         ms.recordactions()
 
         if not didwork and pats:
             hint = None
             if not any([p for p in pats if p.find(':') >= 0]):
                 pats = ['path:%s' % p for p in pats]
                 m = scmutil.match(wctx, pats, opts)
                 for f in ms:
                     if not m(f):
                         continue
                     flags = ''.join(['-%s ' % o[0] for o in flaglist
                                                    if opts.get(o)])
                     hint = _("(try: hg resolve %s%s)\n") % (
                              flags,
                              ' '.join(pats))
                     break
             ui.warn(_("arguments do not match paths that need resolving\n"))
             if hint:
                 ui.warn(hint)
         elif ms.mergedriver and ms.mdstate() != 's':
             # run conclude step when either a driver-resolved file is requested
             # or there are no driver-resolved files
             # we can't use 'ret' to determine whether any files are unresolved
             # because we might not have tried to resolve some
             if ((runconclude or not list(ms.driverresolved()))
                 and not list(ms.unresolved())):
                 proceed = mergemod.driverconclude(repo, ms, wctx)
                 ms.commit()
                 if not proceed:
                     return 1
 
     # Nudge users into finishing an unfinished operation
     unresolvedf = list(ms.unresolved())
     driverresolvedf = list(ms.driverresolved())
     if not unresolvedf and not driverresolvedf:
         ui.status(_('(no more unresolved files)\n'))
         cmdutil.checkafterresolved(repo)
     elif not unresolvedf:
         ui.status(_('(no more unresolved files -- '
                     'run "hg resolve --all" to conclude)\n'))
 
     return ret
 
 @command('revert',
     [('a', 'all', None, _('revert all changes when no arguments given')),
     ('d', 'date', '', _('tipmost revision matching date'), _('DATE')),
     ('r', 'rev', '', _('revert to the specified revision'), _('REV')),
     ('C', 'no-backup', None, _('do not save backup copies of files')),
     ('i', 'interactive', None,
             _('interactively select the changes (EXPERIMENTAL)')),
     ] + walkopts + dryrunopts,
     _('[OPTION]... [-r REV] [NAME]...'))
 def revert(ui, repo, *pats, **opts):
     """restore files to their checkout state
 
     .. note::
 
        To check out earlier revisions, you should use :hg:`update REV`.
        To cancel an uncommitted merge (and lose your changes),
        use :hg:`update --clean .`.
 
     With no revision specified, revert the specified files or directories
     to the contents they had in the parent of the working directory.
     This restores the contents of files to an unmodified
     state and unschedules adds, removes, copies, and renames. If the
     working directory has two parents, you must explicitly specify a
     revision.
 
     Using the -r/--rev or -d/--date options, revert the given files or
     directories to their states as of a specific revision. Because
     revert does not change the working directory parents, this will
     cause these files to appear modified. This can be helpful to "back
     out" some or all of an earlier change. See :hg:`backout` for a
     related method.
 
     Modified files are saved with a .orig suffix before reverting.
     To disable these backups, use --no-backup. It is possible to store
     the backup files in a custom directory relative to the root of the
     repository by setting the ``ui.origbackuppath`` configuration
     option.
 
     See :hg:`help dates` for a list of formats valid for -d/--date.
 
     See :hg:`help backout` for a way to reverse the effect of an
     earlier changeset.
 
     Returns 0 on success.
     """
 
     if opts.get("date"):
         if opts.get("rev"):
             raise error.Abort(_("you can't specify a revision and a date"))
         opts["rev"] = cmdutil.finddate(ui, repo, opts["date"])
 
     parent, p2 = repo.dirstate.parents()
     if not opts.get('rev') and p2 != nullid:
         # revert after merge is a trap for new users (issue2915)
         raise error.Abort(_('uncommitted merge with no revision specified'),
                          hint=_("use 'hg update' or see 'hg help revert'"))
 
     ctx = scmutil.revsingle(repo, opts.get('rev'))
 
     if (not (pats or opts.get('include') or opts.get('exclude') or
              opts.get('all') or opts.get('interactive'))):
         msg = _("no files or directories specified")
         if p2 != nullid:
             hint = _("uncommitted merge, use --all to discard all changes,"
                      " or 'hg update -C .' to abort the merge")
             raise error.Abort(msg, hint=hint)
         dirty = any(repo.status())
         node = ctx.node()
         if node != parent:
             if dirty:
                 hint = _("uncommitted changes, use --all to discard all"
                          " changes, or 'hg update %s' to update") % ctx.rev()
             else:
                 hint = _("use --all to revert all files,"
                          " or 'hg update %s' to update") % ctx.rev()
         elif dirty:
             hint = _("uncommitted changes, use --all to discard all changes")
         else:
             hint = _("use --all to revert all files")
         raise error.Abort(msg, hint=hint)
 
     return cmdutil.revert(ui, repo, ctx, (parent, p2), *pats, **opts)
 
 @command('rollback', dryrunopts +
          [('f', 'force', False, _('ignore safety measures'))])
 def rollback(ui, repo, **opts):
     """roll back the last transaction (DANGEROUS) (DEPRECATED)
 
     Please use :hg:`commit --amend` instead of rollback to correct
     mistakes in the last commit.
 
     This command should be used with care. There is only one level of
     rollback, and there is no way to undo a rollback. It will also
     restore the dirstate at the time of the last transaction, losing
     any dirstate changes since that time. This command does not alter
     the working directory.
 
     Transactions are used to encapsulate the effects of all commands
     that create new changesets or propagate existing changesets into a
     repository.
 
     .. container:: verbose
 
       For example, the following commands are transactional, and their
       effects can be rolled back:
 
       - commit
       - import
       - pull
       - push (with this repository as the destination)
       - unbundle
 
       To avoid permanent data loss, rollback will refuse to rollback a
       commit transaction if it isn't checked out. Use --force to
       override this protection.
 
       The rollback command can be entirely disabled by setting the
       ``ui.rollback`` configuration setting to false. If you're here
       because you want to use rollback and it's disabled, you can
       re-enable the command by setting ``ui.rollback`` to true.
 
     This command is not intended for use on public repositories. Once
     changes are visible for pull by other users, rolling a transaction
     back locally is ineffective (someone else may already have pulled
     the changes). Furthermore, a race is possible with readers of the
     repository; for example an in-progress pull from the repository
     may fail if a rollback is performed.
 
     Returns 0 on success, 1 if no rollback data is available.
     """
     if not ui.configbool('ui', 'rollback', True):
         raise error.Abort(_('rollback is disabled because it is unsafe'),
                           hint=('see `hg help -v rollback` for information'))
     return repo.rollback(dryrun=opts.get('dry_run'),
                          force=opts.get('force'))
 
 @command('root', [])
 def root(ui, repo):
     """print the root (top) of the current working directory
 
     Print the root directory of the current repository.
 
     Returns 0 on success.
     """
     ui.write(repo.root + "\n")
 
 @command('^serve',
     [('A', 'accesslog', '', _('name of access log file to write to'),
      _('FILE')),
     ('d', 'daemon', None, _('run server in background')),
     ('', 'daemon-postexec', [], _('used internally by daemon mode')),
     ('E', 'errorlog', '', _('name of error log file to write to'), _('FILE')),
     # use string type, then we can check if something was passed
     ('p', 'port', '', _('port to listen on (default: 8000)'), _('PORT')),
     ('a', 'address', '', _('address to listen on (default: all interfaces)'),
      _('ADDR')),
     ('', 'prefix', '', _('prefix path to serve from (default: server root)'),
      _('PREFIX')),
     ('n', 'name', '',
      _('name to show in web pages (default: working directory)'), _('NAME')),
     ('', 'web-conf', '',
      _("name of the hgweb config file (see 'hg help hgweb')"), _('FILE')),
     ('', 'webdir-conf', '', _('name of the hgweb config file (DEPRECATED)'),
      _('FILE')),
     ('', 'pid-file', '', _('name of file to write process ID to'), _('FILE')),
     ('', 'stdio', None, _('for remote clients')),
     ('', 'cmdserver', '', _('for remote clients'), _('MODE')),
     ('t', 'templates', '', _('web templates to use'), _('TEMPLATE')),
     ('', 'style', '', _('template style to use'), _('STYLE')),
     ('6', 'ipv6', None, _('use IPv6 in addition to IPv4')),
     ('', 'certificate', '', _('SSL certificate file'), _('FILE'))],
     _('[OPTION]...'),
     optionalrepo=True)
 def serve(ui, repo, **opts):
     """start stand-alone webserver
 
     Start a local HTTP repository browser and pull server. You can use
     this for ad-hoc sharing and browsing of repositories. It is
     recommended to use a real web server to serve a repository for
     longer periods of time.
 
     Please note that the server does not implement access control.
     This means that, by default, anybody can read from the server and
     nobody can write to it by default. Set the ``web.allow_push``
     option to ``*`` to allow everybody to push to the server. You
     should use a real web server if you need to authenticate users.
 
     By default, the server logs accesses to stdout and errors to
     stderr. Use the -A/--accesslog and -E/--errorlog options to log to
     files.
 
     To have the server choose a free port number to listen on, specify
     a port number of 0; in this case, the server will print the port
     number it uses.
 
     Returns 0 on success.
     """
 
     if opts["stdio"] and opts["cmdserver"]:
         raise error.Abort(_("cannot use --stdio with --cmdserver"))
 
     if opts["stdio"]:
         if repo is None:
             raise error.RepoError(_("there is no Mercurial repository here"
                                     " (.hg not found)"))
         s = sshserver.sshserver(ui, repo)
         s.serve_forever()
 
     service = server.createservice(ui, repo, opts)
     return server.runservice(opts, initfn=service.init, runfn=service.run)
 
 @command('^status|st',
     [('A', 'all', None, _('show status of all files')),
     ('m', 'modified', None, _('show only modified files')),
     ('a', 'added', None, _('show only added files')),
     ('r', 'removed', None, _('show only removed files')),
     ('d', 'deleted', None, _('show only deleted (but tracked) files')),
     ('c', 'clean', None, _('show only files without changes')),
     ('u', 'unknown', None, _('show only unknown (not tracked) files')),
     ('i', 'ignored', None, _('show only ignored files')),
     ('n', 'no-status', None, _('hide status prefix')),
     ('C', 'copies', None, _('show source of copied files')),
     ('0', 'print0', None, _('end filenames with NUL, for use with xargs')),
     ('', 'rev', [], _('show difference from revision'), _('REV')),
     ('', 'change', '', _('list the changed files of a revision'), _('REV')),
     ] + walkopts + subrepoopts + formatteropts,
     _('[OPTION]... [FILE]...'),
     inferrepo=True)
 def status(ui, repo, *pats, **opts):
     """show changed files in the working directory
 
     Show status of files in the repository. If names are given, only
     files that match are shown. Files that are clean or ignored or
     the source of a copy/move operation, are not listed unless
     -c/--clean, -i/--ignored, -C/--copies or -A/--all are given.
     Unless options described with "show only ..." are given, the
     options -mardu are used.
 
     Option -q/--quiet hides untracked (unknown and ignored) files
     unless explicitly requested with -u/--unknown or -i/--ignored.
 
     .. note::
 
        :hg:`status` may appear to disagree with diff if permissions have
        changed or a merge has occurred. The standard diff format does
        not report permission changes and diff only reports changes
        relative to one merge parent.
 
     If one revision is given, it is used as the base revision.
     If two revisions are given, the differences between them are
     shown. The --change option can also be used as a shortcut to list
     the changed files of a revision from its first parent.
 
     The codes used to show the status of files are::
 
       M = modified
       A = added
       R = removed
       C = clean
       ! = missing (deleted by non-hg command, but still tracked)
       ? = not tracked
       I = ignored
         = origin of the previous file (with --copies)
 
     .. container:: verbose
 
       Examples:
 
       - show changes in the working directory relative to a
         changeset::
 
           hg status --rev 9353
 
       - show changes in the working directory relative to the
         current directory (see :hg:`help patterns` for more information)::
 
           hg status re:
 
       - show all changes including copies in an existing changeset::
 
           hg status --copies --change 9353
 
       - get a NUL separated list of added files, suitable for xargs::
 
           hg status -an0
 
     Returns 0 on success.
     """
 
     revs = opts.get('rev')
     change = opts.get('change')
 
     if revs and change:
         msg = _('cannot specify --rev and --change at the same time')
         raise error.Abort(msg)
     elif change:
         node2 = scmutil.revsingle(repo, change, None).node()
         node1 = repo[node2].p1().node()
     else:
         node1, node2 = scmutil.revpair(repo, revs)
 
     if pats:
         cwd = repo.getcwd()
     else:
         cwd = ''
 
     if opts.get('print0'):
         end = '\0'
     else:
         end = '\n'
     copy = {}
     states = 'modified added removed deleted unknown ignored clean'.split()
     show = [k for k in states if opts.get(k)]
     if opts.get('all'):
         show += ui.quiet and (states[:4] + ['clean']) or states
     if not show:
         if ui.quiet:
             show = states[:4]
         else:
             show = states[:5]
 
     m = scmutil.match(repo[node2], pats, opts)
     stat = repo.status(node1, node2, m,
                        'ignored' in show, 'clean' in show, 'unknown' in show,
                        opts.get('subrepos'))
     changestates = zip(states, 'MAR!?IC', stat)
 
     if (opts.get('all') or opts.get('copies')
         or ui.configbool('ui', 'statuscopies')) and not opts.get('no_status'):
         copy = copies.pathcopies(repo[node1], repo[node2], m)
 
     fm = ui.formatter('status', opts)
     fmt = '%s' + end
     showchar = not opts.get('no_status')
 
     for state, char, files in changestates:
         if state in show:
             label = 'status.' + state
             for f in files:
                 fm.startitem()
                 fm.condwrite(showchar, 'status', '%s ', char, label=label)
                 fm.write('path', fmt, repo.pathto(f, cwd), label=label)
                 if f in copy:
                     fm.write("copy", '  %s' + end, repo.pathto(copy[f], cwd),
                              label='status.copied')
     fm.end()
 
 @command('^summary|sum',
     [('', 'remote', None, _('check for push and pull'))], '[--remote]')
 def summary(ui, repo, **opts):
     """summarize working directory state
 
     This generates a brief summary of the working directory state,
     including parents, branch, commit status, phase and available updates.
 
     With the --remote option, this will check the default paths for
     incoming and outgoing changes. This can be time-consuming.
 
     Returns 0 on success.
     """
 
     ctx = repo[None]
     parents = ctx.parents()
     pnode = parents[0].node()
     marks = []
 
     ms = None
     try:
         ms = mergemod.mergestate.read(repo)
     except error.UnsupportedMergeRecords as e:
         s = ' '.join(e.recordtypes)
         ui.warn(
             _('warning: merge state has unsupported record types: %s\n') % s)
         unresolved = 0
     else:
         unresolved = [f for f in ms if ms[f] == 'u']
 
     for p in parents:
         # label with log.changeset (instead of log.parent) since this
         # shows a working directory parent *changeset*:
         # i18n: column positioning for "hg summary"
         ui.write(_('parent: %d:%s ') % (p.rev(), str(p)),
                  label='log.changeset changeset.%s' % p.phasestr())
         ui.write(' '.join(p.tags()), label='log.tag')
         if p.bookmarks():
             marks.extend(p.bookmarks())
         if p.rev() == -1:
             if not len(repo):
                 ui.write(_(' (empty repository)'))
             else:
                 ui.write(_(' (no revision checked out)'))
         ui.write('\n')
         if p.description():
             ui.status(' ' + p.description().splitlines()[0].strip() + '\n',
                       label='log.summary')
 
     branch = ctx.branch()
     bheads = repo.branchheads(branch)
     # i18n: column positioning for "hg summary"
     m = _('branch: %s\n') % branch
     if branch != 'default':
         ui.write(m, label='log.branch')
     else:
         ui.status(m, label='log.branch')
 
     if marks:
         active = repo._activebookmark
         # i18n: column positioning for "hg summary"
         ui.write(_('bookmarks:'), label='log.bookmark')
         if active is not None:
             if active in marks:
                 ui.write(' *' + active, label=activebookmarklabel)
                 marks.remove(active)
             else:
                 ui.write(' [%s]' % active, label=activebookmarklabel)
         for m in marks:
             ui.write(' ' + m, label='log.bookmark')
         ui.write('\n', label='log.bookmark')
 
     status = repo.status(unknown=True)
 
     c = repo.dirstate.copies()
     copied, renamed = [], []
     for d, s in c.iteritems():
         if s in status.removed:
             status.removed.remove(s)
             renamed.append(d)
         else:
             copied.append(d)
         if d in status.added:
             status.added.remove(d)
 
     subs = [s for s in ctx.substate if ctx.sub(s).dirty()]
 
     labels = [(ui.label(_('%d modified'), 'status.modified'), status.modified),
               (ui.label(_('%d added'), 'status.added'), status.added),
               (ui.label(_('%d removed'), 'status.removed'), status.removed),
               (ui.label(_('%d renamed'), 'status.copied'), renamed),
               (ui.label(_('%d copied'), 'status.copied'), copied),
               (ui.label(_('%d deleted'), 'status.deleted'), status.deleted),
               (ui.label(_('%d unknown'), 'status.unknown'), status.unknown),
               (ui.label(_('%d unresolved'), 'resolve.unresolved'), unresolved),
               (ui.label(_('%d subrepos'), 'status.modified'), subs)]
     t = []
     for l, s in labels:
         if s:
             t.append(l % len(s))
 
     t = ', '.join(t)
     cleanworkdir = False
 
     if repo.vfs.exists('graftstate'):
         t += _(' (graft in progress)')
     if repo.vfs.exists('updatestate'):
         t += _(' (interrupted update)')
     elif len(parents) > 1:
         t += _(' (merge)')
     elif branch != parents[0].branch():
         t += _(' (new branch)')
     elif (parents[0].closesbranch() and
           pnode in repo.branchheads(branch, closed=True)):
         t += _(' (head closed)')
     elif not (status.modified or status.added or status.removed or renamed or
               copied or subs):
         t += _(' (clean)')
         cleanworkdir = True
     elif pnode not in bheads:
         t += _(' (new branch head)')
 
     if parents:
         pendingphase = max(p.phase() for p in parents)
     else:
         pendingphase = phases.public
 
     if pendingphase > phases.newcommitphase(ui):
         t += ' (%s)' % phases.phasenames[pendingphase]
 
     if cleanworkdir:
         # i18n: column positioning for "hg summary"
         ui.status(_('commit: %s\n') % t.strip())
     else:
         # i18n: column positioning for "hg summary"
         ui.write(_('commit: %s\n') % t.strip())
 
     # all ancestors of branch heads - all ancestors of parent = new csets
     new = len(repo.changelog.findmissing([pctx.node() for pctx in parents],
                                          bheads))
 
     if new == 0:
         # i18n: column positioning for "hg summary"
         ui.status(_('update: (current)\n'))
     elif pnode not in bheads:
         # i18n: column positioning for "hg summary"
         ui.write(_('update: %d new changesets (update)\n') % new)
     else:
         # i18n: column positioning for "hg summary"
         ui.write(_('update: %d new changesets, %d branch heads (merge)\n') %
                  (new, len(bheads)))
 
     t = []
     draft = len(repo.revs('draft()'))
     if draft:
         t.append(_('%d draft') % draft)
     secret = len(repo.revs('secret()'))
     if secret:
         t.append(_('%d secret') % secret)
 
     if draft or secret:
         ui.status(_('phases: %s\n') % ', '.join(t))
 
     if obsolete.isenabled(repo, obsolete.createmarkersopt):
         for trouble in ("unstable", "divergent", "bumped"):
             numtrouble = len(repo.revs(trouble + "()"))
             # We write all the possibilities to ease translation
             troublemsg = {
                "unstable": _("unstable: %d changesets"),
                "divergent": _("divergent: %d changesets"),
                "bumped": _("bumped: %d changesets"),
             }
             if numtrouble > 0:
                 ui.status(troublemsg[trouble] % numtrouble + "\n")
 
     cmdutil.summaryhooks(ui, repo)
 
     if opts.get('remote'):
         needsincoming, needsoutgoing = True, True
     else:
         needsincoming, needsoutgoing = False, False
         for i, o in cmdutil.summaryremotehooks(ui, repo, opts, None):
             if i:
                 needsincoming = True
             if o:
                 needsoutgoing = True
         if not needsincoming and not needsoutgoing:
             return
 
     def getincoming():
         source, branches = hg.parseurl(ui.expandpath('default'))
         sbranch = branches[0]
         try:
             other = hg.peer(repo, {}, source)
         except error.RepoError:
             if opts.get('remote'):
                 raise
             return source, sbranch, None, None, None
         revs, checkout = hg.addbranchrevs(repo, other, branches, None)
         if revs:
             revs = [other.lookup(rev) for rev in revs]
         ui.debug('comparing with %s\n' % util.hidepassword(source))
         repo.ui.pushbuffer()
         commoninc = discovery.findcommonincoming(repo, other, heads=revs)
         repo.ui.popbuffer()
         return source, sbranch, other, commoninc, commoninc[1]
 
     if needsincoming:
         source, sbranch, sother, commoninc, incoming = getincoming()
     else:
         source = sbranch = sother = commoninc = incoming = None
 
     def getoutgoing():
         dest, branches = hg.parseurl(ui.expandpath('default-push', 'default'))
         dbranch = branches[0]
         revs, checkout = hg.addbranchrevs(repo, repo, branches, None)
         if source != dest:
             try:
                 dother = hg.peer(repo, {}, dest)
             except error.RepoError:
                 if opts.get('remote'):
                     raise
                 return dest, dbranch, None, None
             ui.debug('comparing with %s\n' % util.hidepassword(dest))
         elif sother is None:
             # there is no explicit destination peer, but source one is invalid
             return dest, dbranch, None, None
         else:
             dother = sother
         if (source != dest or (sbranch is not None and sbranch != dbranch)):
             common = None
         else:
             common = commoninc
         if revs:
             revs = [repo.lookup(rev) for rev in revs]
         repo.ui.pushbuffer()
         outgoing = discovery.findcommonoutgoing(repo, dother, onlyheads=revs,
                                                 commoninc=common)
         repo.ui.popbuffer()
         return dest, dbranch, dother, outgoing
 
     if needsoutgoing:
         dest, dbranch, dother, outgoing = getoutgoing()
     else:
         dest = dbranch = dother = outgoing = None
 
     if opts.get('remote'):
         t = []
         if incoming:
             t.append(_('1 or more incoming'))
         o = outgoing.missing
         if o:
             t.append(_('%d outgoing') % len(o))
         other = dother or sother
         if 'bookmarks' in other.listkeys('namespaces'):
             counts = bookmarks.summary(repo, other)
             if counts[0] > 0:
                 t.append(_('%d incoming bookmarks') % counts[0])
             if counts[1] > 0:
                 t.append(_('%d outgoing bookmarks') % counts[1])
 
         if t:
             # i18n: column positioning for "hg summary"
             ui.write(_('remote: %s\n') % (', '.join(t)))
         else:
             # i18n: column positioning for "hg summary"
             ui.status(_('remote: (synced)\n'))
 
     cmdutil.summaryremotehooks(ui, repo, opts,
                                ((source, sbranch, sother, commoninc),
                                 (dest, dbranch, dother, outgoing)))
 
 @command('tag',
     [('f', 'force', None, _('force tag')),
     ('l', 'local', None, _('make the tag local')),
     ('r', 'rev', '', _('revision to tag'), _('REV')),
     ('', 'remove', None, _('remove a tag')),
     # -l/--local is already there, commitopts cannot be used
     ('e', 'edit', None, _('invoke editor on commit messages')),
     ('m', 'message', '', _('use text as commit message'), _('TEXT')),
     ] + commitopts2,
     _('[-f] [-l] [-m TEXT] [-d DATE] [-u USER] [-r REV] NAME...'))
 def tag(ui, repo, name1, *names, **opts):
     """add one or more tags for the current or given revision
 
     Name a particular revision using <name>.
 
     Tags are used to name particular revisions of the repository and are
     very useful to compare different revisions, to go back to significant
     earlier versions or to mark branch points as releases, etc. Changing
     an existing tag is normally disallowed; use -f/--force to override.
 
     If no revision is given, the parent of the working directory is
     used.
 
     To facilitate version control, distribution, and merging of tags,
     they are stored as a file named ".hgtags" which is managed similarly
     to other project files and can be hand-edited if necessary. This
     also means that tagging creates a new commit. The file
     ".hg/localtags" is used for local tags (not shared among
     repositories).
 
     Tag commits are usually made at the head of a branch. If the parent
     of the working directory is not a branch head, :hg:`tag` aborts; use
     -f/--force to force the tag commit to be based on a non-head
     changeset.
 
     See :hg:`help dates` for a list of formats valid for -d/--date.
 
     Since tag names have priority over branch names during revision
     lookup, using an existing branch name as a tag name is discouraged.
 
     Returns 0 on success.
     """
     wlock = lock = None
     try:
         wlock = repo.wlock()
         lock = repo.lock()
         rev_ = "."
         names = [t.strip() for t in (name1,) + names]
         if len(names) != len(set(names)):
             raise error.Abort(_('tag names must be unique'))
         for n in names:
             scmutil.checknewlabel(repo, n, 'tag')
             if not n:
                 raise error.Abort(_('tag names cannot consist entirely of '
                                    'whitespace'))
         if opts.get('rev') and opts.get('remove'):
             raise error.Abort(_("--rev and --remove are incompatible"))
         if opts.get('rev'):
             rev_ = opts['rev']
         message = opts.get('message')
         if opts.get('remove'):
             if opts.get('local'):
                 expectedtype = 'local'
             else:
                 expectedtype = 'global'
 
             for n in names:
                 if not repo.tagtype(n):
                     raise error.Abort(_("tag '%s' does not exist") % n)
                 if repo.tagtype(n) != expectedtype:
                     if expectedtype == 'global':
                         raise error.Abort(_("tag '%s' is not a global tag") % n)
                     else:
                         raise error.Abort(_("tag '%s' is not a local tag") % n)
             rev_ = 'null'
             if not message:
                 # we don't translate commit messages
                 message = 'Removed tag %s' % ', '.join(names)
         elif not opts.get('force'):
             for n in names:
                 if n in repo.tags():
                     raise error.Abort(_("tag '%s' already exists "
                                        "(use -f to force)") % n)
         if not opts.get('local'):
             p1, p2 = repo.dirstate.parents()
             if p2 != nullid:
                 raise error.Abort(_('uncommitted merge'))
             bheads = repo.branchheads()
             if not opts.get('force') and bheads and p1 not in bheads:
                 raise error.Abort(_('working directory is not at a branch head '
                                     '(use -f to force)'))
         r = scmutil.revsingle(repo, rev_).node()
 
         if not message:
             # we don't translate commit messages
             message = ('Added tag %s for changeset %s' %
                        (', '.join(names), short(r)))
 
         date = opts.get('date')
         if date:
             date = util.parsedate(date)
 
         if opts.get('remove'):
             editform = 'tag.remove'
         else:
             editform = 'tag.add'
         editor = cmdutil.getcommiteditor(editform=editform, **opts)
 
         # don't allow tagging the null rev
         if (not opts.get('remove') and
             scmutil.revsingle(repo, rev_).rev() == nullrev):
             raise error.Abort(_("cannot tag null revision"))
 
         repo.tag(names, r, message, opts.get('local'), opts.get('user'), date,
                  editor=editor)
     finally:
         release(lock, wlock)
 
 @command('tags', formatteropts, '')
 def tags(ui, repo, **opts):
     """list repository tags
 
     This lists both regular and local tags. When the -v/--verbose
     switch is used, a third column "local" is printed for local tags.
     When the -q/--quiet switch is used, only the tag name is printed.
 
     Returns 0 on success.
     """
 
     fm = ui.formatter('tags', opts)
     hexfunc = fm.hexfunc
     tagtype = ""
 
     for t, n in reversed(repo.tagslist()):
         hn = hexfunc(n)
         label = 'tags.normal'
         tagtype = ''
         if repo.tagtype(t) == 'local':
             label = 'tags.local'
             tagtype = 'local'
 
         fm.startitem()
         fm.write('tag', '%s', t, label=label)
         fmt = " " * (30 - encoding.colwidth(t)) + ' %5d:%s'
         fm.condwrite(not ui.quiet, 'rev node', fmt,
                      repo.changelog.rev(n), hn, label=label)
         fm.condwrite(ui.verbose and tagtype, 'type', ' %s',
                      tagtype, label=label)
         fm.plain('\n')
     fm.end()
 
 @command('tip',
     [('p', 'patch', None, _('show patch')),
     ('g', 'git', None, _('use git extended diff format')),
     ] + templateopts,
     _('[-p] [-g]'))
 def tip(ui, repo, **opts):
     """show the tip revision (DEPRECATED)
 
     The tip revision (usually just called the tip) is the changeset
     most recently added to the repository (and therefore the most
     recently changed head).
 
     If you have just made a commit, that commit will be the tip. If
     you have just pulled changes from another repository, the tip of
     that repository becomes the current tip. The "tip" tag is special
     and cannot be renamed or assigned to a different changeset.
 
     This command is deprecated, please use :hg:`heads` instead.
 
     Returns 0 on success.
     """
     displayer = cmdutil.show_changeset(ui, repo, opts)
     displayer.show(repo['tip'])
     displayer.close()
 
 @command('unbundle',
     [('u', 'update', None,
      _('update to new branch head if changesets were unbundled'))],
     _('[-u] FILE...'))
 def unbundle(ui, repo, fname1, *fnames, **opts):
     """apply one or more changegroup files
 
     Apply one or more compressed changegroup files generated by the
     bundle command.
 
     Returns 0 on success, 1 if an update has unresolved files.
     """
     fnames = (fname1,) + fnames
 
     with repo.lock():
         for fname in fnames:
             f = hg.openpath(ui, fname)
             gen = exchange.readbundle(ui, f, fname)
             if isinstance(gen, bundle2.unbundle20):
                 tr = repo.transaction('unbundle')
                 try:
                     op = bundle2.applybundle(repo, gen, tr, source='unbundle',
                                              url='bundle:' + fname)
                     tr.close()
                 except error.BundleUnknownFeatureError as exc:
                     raise error.Abort(_('%s: unknown bundle feature, %s')
                                       % (fname, exc),
                                       hint=_("see https://mercurial-scm.org/"
                                              "wiki/BundleFeature for more "
                                              "information"))
                 finally:
                     if tr:
                         tr.release()
                 changes = [r.get('return', 0)
                            for r in op.records['changegroup']]
                 modheads = changegroup.combineresults(changes)
             elif isinstance(gen, streamclone.streamcloneapplier):
                 raise error.Abort(
                         _('packed bundles cannot be applied with '
                           '"hg unbundle"'),
                         hint=_('use "hg debugapplystreamclonebundle"'))
             else:
                 modheads = gen.apply(repo, 'unbundle', 'bundle:' + fname)
 
     return postincoming(ui, repo, modheads, opts.get('update'), None, None)
 
 @command('^update|up|checkout|co',
     [('C', 'clean', None, _('discard uncommitted changes (no backup)')),
     ('c', 'check', None, _('require clean working directory')),
     ('d', 'date', '', _('tipmost revision matching date'), _('DATE')),
     ('r', 'rev', '', _('revision'), _('REV'))
      ] + mergetoolopts,
     _('[-c] [-C] [-d DATE] [[-r] REV]'))
 def update(ui, repo, node=None, rev=None, clean=False, date=None, check=False,
            tool=None):
     """update working directory (or switch revisions)
 
     Update the repository's working directory to the specified
     changeset. If no changeset is specified, update to the tip of the
     current named branch and move the active bookmark (see :hg:`help
     bookmarks`).
 
     Update sets the working directory's parent revision to the specified
     changeset (see :hg:`help parents`).
 
     If the changeset is not a descendant or ancestor of the working
     directory's parent, the update is aborted. With the -c/--check
     option, the working directory is checked for uncommitted changes; if
     none are found, the working directory is updated to the specified
     changeset.
 
     .. container:: verbose
 
       The following rules apply when the working directory contains
       uncommitted changes:
 
       1. If neither -c/--check nor -C/--clean is specified, and if
          the requested changeset is an ancestor or descendant of
          the working directory's parent, the uncommitted changes
          are merged into the requested changeset and the merged
          result is left uncommitted. If the requested changeset is
          not an ancestor or descendant (that is, it is on another
          branch), the update is aborted and the uncommitted changes
          are preserved.
 
       2. With the -c/--check option, the update is aborted and the
          uncommitted changes are preserved.
 
       3. With the -C/--clean option, uncommitted changes are discarded and
          the working directory is updated to the requested changeset.
 
     To cancel an uncommitted merge (and lose your changes), use
     :hg:`update --clean .`.
 
     Use null as the changeset to remove the working directory (like
     :hg:`clone -U`).
 
     If you want to revert just one file to an older revision, use
     :hg:`revert [-r REV] NAME`.
 
     See :hg:`help dates` for a list of formats valid for -d/--date.
 
     Returns 0 on success, 1 if there are unresolved files.
     """
     if rev and node:
         raise error.Abort(_("please specify just one revision"))
 
     if rev is None or rev == '':
         rev = node
 
     if date and rev is not None:
         raise error.Abort(_("you can't specify a revision and a date"))
 
     if check and clean:
         raise error.Abort(_("cannot specify both -c/--check and -C/--clean"))
 
     with repo.wlock():
         cmdutil.clearunfinished(repo)
 
         if date:
             rev = cmdutil.finddate(ui, repo, date)
 
         # if we defined a bookmark, we have to remember the original name
         brev = rev
         rev = scmutil.revsingle(repo, rev, rev).rev()
 
         if check:
             cmdutil.bailifchanged(repo, merge=False)
 
         repo.ui.setconfig('ui', 'forcemerge', tool, 'update')
 
         return hg.updatetotally(ui, repo, rev, brev, clean=clean, check=check)
 
 @command('verify', [])
 def verify(ui, repo):
     """verify the integrity of the repository
 
     Verify the integrity of the current repository.
 
     This will perform an extensive check of the repository's
     integrity, validating the hashes and checksums of each entry in
     the changelog, manifest, and tracked files, as well as the
     integrity of their crosslinks and indices.
 
     Please see https://mercurial-scm.org/wiki/RepositoryCorruption
     for more information about recovery from corruption of the
     repository.
 
     Returns 0 on success, 1 if errors are encountered.
     """
     return hg.verify(repo)
 
 @command('version', [] + formatteropts, norepo=True)
 def version_(ui, **opts):
     """output version and copyright information"""
     fm = ui.formatter("version", opts)
     fm.startitem()
     fm.write("ver", _("Mercurial Distributed SCM (version %s)\n"),
              util.version())
     license = _(
         "(see https://mercurial-scm.org for more information)\n"
         "\nCopyright (C) 2005-2016 Matt Mackall and others\n"
         "This is free software; see the source for copying conditions. "
         "There is NO\nwarranty; "
         "not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n"
     )
     if not ui.quiet:
         fm.plain(license)
 
     if ui.verbose:
         fm.plain(_("\nEnabled extensions:\n\n"))
     # format names and versions into columns
     names = []
     vers = []
     isinternals = []
     for name, module in extensions.extensions():
         names.append(name)
         vers.append(extensions.moduleversion(module) or None)
         isinternals.append(extensions.ismoduleinternal(module))
     fn = fm.nested("extensions")
     if names:
         namefmt = "  %%-%ds  " % max(len(n) for n in names)
         places = [_("external"), _("internal")]
         for n, v, p in zip(names, vers, isinternals):
             fn.startitem()
             fn.condwrite(ui.verbose, "name", namefmt, n)
             if ui.verbose:
                 fn.plain("%s  " % places[p])
             fn.data(bundled=p)
             fn.condwrite(ui.verbose and v, "ver", "%s", v)
             if ui.verbose:
                 fn.plain("\n")
     fn.end()
     fm.end()
 
 def loadcmdtable(ui, name, cmdtable):
     """Load command functions from specified cmdtable
     """
     overrides = [cmd for cmd in cmdtable if cmd in table]
     if overrides:
         ui.warn(_("extension '%s' overrides commands: %s\n")
                 % (name, " ".join(overrides)))
     table.update(cmdtable)

mercurial/i18n.py

@@ -1,109 +1,109
 # i18n.py - internationalization support for mercurial
 #
 # Copyright 2005, 2006 Matt Mackall <[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.
 
 from __future__ import absolute_import
 
 import gettext as gettextmod
 import locale
 import os
 import sys
 
 from . import (
     encoding,
     pycompat,
 )
 
 # modelled after templater.templatepath:
 if getattr(sys, 'frozen', None) is not None:
-    module = sys.executable
+    module = pycompat.sysexecutable
 else:
     module = __file__
 
 try:
     unicode
 except NameError:
     unicode = str
 
 _languages = None
 if (pycompat.osname == 'nt'
     and 'LANGUAGE' not in encoding.environ
     and 'LC_ALL' not in encoding.environ
     and 'LC_MESSAGES' not in encoding.environ
     and 'LANG' not in encoding.environ):
     # Try to detect UI language by "User Interface Language Management" API
     # if no locale variables are set. Note that locale.getdefaultlocale()
     # uses GetLocaleInfo(), which may be different from UI language.
     # (See http://msdn.microsoft.com/en-us/library/dd374098(v=VS.85).aspx )
     try:
         import ctypes
         langid = ctypes.windll.kernel32.GetUserDefaultUILanguage()
         _languages = [locale.windows_locale[langid]]
     except (ImportError, AttributeError, KeyError):
         # ctypes not found or unknown langid
         pass
 
 _ugettext = None
 
 def setdatapath(datapath):
     datapath = pycompat.fsdecode(datapath)
     localedir = os.path.join(datapath, pycompat.sysstr('locale'))
     t = gettextmod.translation('hg', localedir, _languages, fallback=True)
     global _ugettext
     try:
         _ugettext = t.ugettext
     except AttributeError:
         _ugettext = t.gettext
 
 _msgcache = {}
 
 def gettext(message):
     """Translate message.
 
     The message is looked up in the catalog to get a Unicode string,
     which is encoded in the local encoding before being returned.
 
     Important: message is restricted to characters in the encoding
     given by sys.getdefaultencoding() which is most likely 'ascii'.
     """
     # If message is None, t.ugettext will return u'None' as the
     # translation whereas our callers expect us to return None.
     if message is None or not _ugettext:
         return message
 
     if message not in _msgcache:
         if type(message) is unicode:
             # goofy unicode docstrings in test
             paragraphs = message.split(u'\n\n')
         else:
             paragraphs = [p.decode("ascii") for p in message.split('\n\n')]
         # Be careful not to translate the empty string -- it holds the
         # meta data of the .po file.
         u = u'\n\n'.join([p and _ugettext(p) or u'' for p in paragraphs])
         try:
             # encoding.tolocal cannot be used since it will first try to
             # decode the Unicode string. Calling u.decode(enc) really
             # means u.encode(sys.getdefaultencoding()).decode(enc). Since
             # the Python encoding defaults to 'ascii', this fails if the
             # translated string use non-ASCII characters.
             encodingstr = pycompat.sysstr(encoding.encoding)
             _msgcache[message] = u.encode(encodingstr, "replace")
         except LookupError:
             # An unknown encoding results in a LookupError.
             _msgcache[message] = message
     return _msgcache[message]
 
 def _plain():
     if ('HGPLAIN' not in encoding.environ
         and 'HGPLAINEXCEPT' not in encoding.environ):
         return False
     exceptions = encoding.environ.get('HGPLAINEXCEPT', '').strip().split(',')
     return 'i18n' not in exceptions
 
 if _plain():
     _ = lambda message: message
 else:
     _ = gettext

mercurial/sslutil.py

@@ -1,847 +1,847
 # sslutil.py - SSL handling for mercurial
 #
 # Copyright 2005, 2006, 2007, 2008 Matt Mackall <[e-mail]>
 # Copyright 2006, 2007 Alexis S. L. Carvalho <[e-mail]>
 # Copyright 2006 Vadim Gelfer <[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.
 
 from __future__ import absolute_import
 
 import hashlib
 import os
 import re
 import ssl
 import sys
 
 from .i18n import _
 from . import (
     error,
     pycompat,
     util,
 )
 
 # Python 2.7.9+ overhauled the built-in SSL/TLS features of Python. It added
 # support for TLS 1.1, TLS 1.2, SNI, system CA stores, etc. These features are
 # all exposed via the "ssl" module.
 #
 # Depending on the version of Python being used, SSL/TLS support is either
 # modern/secure or legacy/insecure. Many operations in this module have
 # separate code paths depending on support in Python.
 
 configprotocols = set([
     'tls1.0',
     'tls1.1',
     'tls1.2',
 ])
 
 hassni = getattr(ssl, 'HAS_SNI', False)
 
 # TLS 1.1 and 1.2 may not be supported if the OpenSSL Python is compiled
 # against doesn't support them.
 supportedprotocols = set(['tls1.0'])
 if util.safehasattr(ssl, 'PROTOCOL_TLSv1_1'):
     supportedprotocols.add('tls1.1')
 if util.safehasattr(ssl, 'PROTOCOL_TLSv1_2'):
     supportedprotocols.add('tls1.2')
 
 try:
     # ssl.SSLContext was added in 2.7.9 and presence indicates modern
     # SSL/TLS features are available.
     SSLContext = ssl.SSLContext
     modernssl = True
     _canloaddefaultcerts = util.safehasattr(SSLContext, 'load_default_certs')
 except AttributeError:
     modernssl = False
     _canloaddefaultcerts = False
 
     # We implement SSLContext using the interface from the standard library.
     class SSLContext(object):
         # ssl.wrap_socket gained the "ciphers" named argument in 2.7.
         _supportsciphers = sys.version_info >= (2, 7)
 
         def __init__(self, protocol):
             # From the public interface of SSLContext
             self.protocol = protocol
             self.check_hostname = False
             self.options = 0
             self.verify_mode = ssl.CERT_NONE
 
             # Used by our implementation.
             self._certfile = None
             self._keyfile = None
             self._certpassword = None
             self._cacerts = None
             self._ciphers = None
 
         def load_cert_chain(self, certfile, keyfile=None, password=None):
             self._certfile = certfile
             self._keyfile = keyfile
             self._certpassword = password
 
         def load_default_certs(self, purpose=None):
             pass
 
         def load_verify_locations(self, cafile=None, capath=None, cadata=None):
             if capath:
                 raise error.Abort(_('capath not supported'))
             if cadata:
                 raise error.Abort(_('cadata not supported'))
 
             self._cacerts = cafile
 
         def set_ciphers(self, ciphers):
             if not self._supportsciphers:
                 raise error.Abort(_('setting ciphers in [hostsecurity] is not '
                                     'supported by this version of Python'),
                                   hint=_('remove the config option or run '
                                          'Mercurial with a modern Python '
                                          'version (preferred)'))
 
             self._ciphers = ciphers
 
         def wrap_socket(self, socket, server_hostname=None, server_side=False):
             # server_hostname is unique to SSLContext.wrap_socket and is used
             # for SNI in that context. So there's nothing for us to do with it
             # in this legacy code since we don't support SNI.
 
             args = {
                 'keyfile': self._keyfile,
                 'certfile': self._certfile,
                 'server_side': server_side,
                 'cert_reqs': self.verify_mode,
                 'ssl_version': self.protocol,
                 'ca_certs': self._cacerts,
             }
 
             if self._supportsciphers:
                 args['ciphers'] = self._ciphers
 
             return ssl.wrap_socket(socket, **args)
 
 def _hostsettings(ui, hostname):
     """Obtain security settings for a hostname.
 
     Returns a dict of settings relevant to that hostname.
     """
     s = {
         # Whether we should attempt to load default/available CA certs
         # if an explicit ``cafile`` is not defined.
         'allowloaddefaultcerts': True,
         # List of 2-tuple of (hash algorithm, hash).
         'certfingerprints': [],
         # Path to file containing concatenated CA certs. Used by
         # SSLContext.load_verify_locations().
         'cafile': None,
         # Whether certificate verification should be disabled.
         'disablecertverification': False,
         # Whether the legacy [hostfingerprints] section has data for this host.
         'legacyfingerprint': False,
         # PROTOCOL_* constant to use for SSLContext.__init__.
         'protocol': None,
         # String representation of minimum protocol to be used for UI
         # presentation.
         'protocolui': None,
         # ssl.CERT_* constant used by SSLContext.verify_mode.
         'verifymode': None,
         # Defines extra ssl.OP* bitwise options to set.
         'ctxoptions': None,
         # OpenSSL Cipher List to use (instead of default).
         'ciphers': None,
     }
 
     # Allow minimum TLS protocol to be specified in the config.
     def validateprotocol(protocol, key):
         if protocol not in configprotocols:
             raise error.Abort(
                 _('unsupported protocol from hostsecurity.%s: %s') %
                 (key, protocol),
                 hint=_('valid protocols: %s') %
                      ' '.join(sorted(configprotocols)))
 
     # We default to TLS 1.1+ where we can because TLS 1.0 has known
     # vulnerabilities (like BEAST and POODLE). We allow users to downgrade to
     # TLS 1.0+ via config options in case a legacy server is encountered.
     if 'tls1.1' in supportedprotocols:
         defaultprotocol = 'tls1.1'
     else:
         # Let people know they are borderline secure.
         # We don't document this config option because we want people to see
         # the bold warnings on the web site.
         # internal config: hostsecurity.disabletls10warning
         if not ui.configbool('hostsecurity', 'disabletls10warning'):
             ui.warn(_('warning: connecting to %s using legacy security '
                       'technology (TLS 1.0); see '
                       'https://mercurial-scm.org/wiki/SecureConnections for '
                       'more info\n') % hostname)
         defaultprotocol = 'tls1.0'
 
     key = 'minimumprotocol'
     protocol = ui.config('hostsecurity', key, defaultprotocol)
     validateprotocol(protocol, key)
 
     key = '%s:minimumprotocol' % hostname
     protocol = ui.config('hostsecurity', key, protocol)
     validateprotocol(protocol, key)
 
     # If --insecure is used, we allow the use of TLS 1.0 despite config options.
     # We always print a "connection security to %s is disabled..." message when
     # --insecure is used. So no need to print anything more here.
     if ui.insecureconnections:
         protocol = 'tls1.0'
 
     s['protocol'], s['ctxoptions'], s['protocolui'] = protocolsettings(protocol)
 
     ciphers = ui.config('hostsecurity', 'ciphers')
     ciphers = ui.config('hostsecurity', '%s:ciphers' % hostname, ciphers)
     s['ciphers'] = ciphers
 
     # Look for fingerprints in [hostsecurity] section. Value is a list
     # of <alg>:<fingerprint> strings.
     fingerprints = ui.configlist('hostsecurity', '%s:fingerprints' % hostname,
                                  [])
     for fingerprint in fingerprints:
         if not (fingerprint.startswith(('sha1:', 'sha256:', 'sha512:'))):
             raise error.Abort(_('invalid fingerprint for %s: %s') % (
                                 hostname, fingerprint),
                               hint=_('must begin with "sha1:", "sha256:", '
                                      'or "sha512:"'))
 
         alg, fingerprint = fingerprint.split(':', 1)
         fingerprint = fingerprint.replace(':', '').lower()
         s['certfingerprints'].append((alg, fingerprint))
 
     # Fingerprints from [hostfingerprints] are always SHA-1.
     for fingerprint in ui.configlist('hostfingerprints', hostname, []):
         fingerprint = fingerprint.replace(':', '').lower()
         s['certfingerprints'].append(('sha1', fingerprint))
         s['legacyfingerprint'] = True
 
     # If a host cert fingerprint is defined, it is the only thing that
     # matters. No need to validate CA certs.
     if s['certfingerprints']:
         s['verifymode'] = ssl.CERT_NONE
         s['allowloaddefaultcerts'] = False
 
     # If --insecure is used, don't take CAs into consideration.
     elif ui.insecureconnections:
         s['disablecertverification'] = True
         s['verifymode'] = ssl.CERT_NONE
         s['allowloaddefaultcerts'] = False
 
     if ui.configbool('devel', 'disableloaddefaultcerts'):
         s['allowloaddefaultcerts'] = False
 
     # If both fingerprints and a per-host ca file are specified, issue a warning
     # because users should not be surprised about what security is or isn't
     # being performed.
     cafile = ui.config('hostsecurity', '%s:verifycertsfile' % hostname)
     if s['certfingerprints'] and cafile:
         ui.warn(_('(hostsecurity.%s:verifycertsfile ignored when host '
                   'fingerprints defined; using host fingerprints for '
                   'verification)\n') % hostname)
 
     # Try to hook up CA certificate validation unless something above
     # makes it not necessary.
     if s['verifymode'] is None:
         # Look at per-host ca file first.
         if cafile:
             cafile = util.expandpath(cafile)
             if not os.path.exists(cafile):
                 raise error.Abort(_('path specified by %s does not exist: %s') %
                                   ('hostsecurity.%s:verifycertsfile' % hostname,
                                    cafile))
             s['cafile'] = cafile
         else:
             # Find global certificates file in config.
             cafile = ui.config('web', 'cacerts')
 
             if cafile:
                 cafile = util.expandpath(cafile)
                 if not os.path.exists(cafile):
                     raise error.Abort(_('could not find web.cacerts: %s') %
                                       cafile)
             elif s['allowloaddefaultcerts']:
                 # CAs not defined in config. Try to find system bundles.
                 cafile = _defaultcacerts(ui)
                 if cafile:
                     ui.debug('using %s for CA file\n' % cafile)
 
             s['cafile'] = cafile
 
         # Require certificate validation if CA certs are being loaded and
         # verification hasn't been disabled above.
         if cafile or (_canloaddefaultcerts and s['allowloaddefaultcerts']):
             s['verifymode'] = ssl.CERT_REQUIRED
         else:
             # At this point we don't have a fingerprint, aren't being
             # explicitly insecure, and can't load CA certs. Connecting
             # is insecure. We allow the connection and abort during
             # validation (once we have the fingerprint to print to the
             # user).
             s['verifymode'] = ssl.CERT_NONE
 
     assert s['protocol'] is not None
     assert s['ctxoptions'] is not None
     assert s['verifymode'] is not None
 
     return s
 
 def protocolsettings(protocol):
     """Resolve the protocol for a config value.
 
     Returns a 3-tuple of (protocol, options, ui value) where the first
     2 items are values used by SSLContext and the last is a string value
     of the ``minimumprotocol`` config option equivalent.
     """
     if protocol not in configprotocols:
         raise ValueError('protocol value not supported: %s' % protocol)
 
     # Despite its name, PROTOCOL_SSLv23 selects the highest protocol
     # that both ends support, including TLS protocols. On legacy stacks,
     # the highest it likely goes is TLS 1.0. On modern stacks, it can
     # support TLS 1.2.
     #
     # The PROTOCOL_TLSv* constants select a specific TLS version
     # only (as opposed to multiple versions). So the method for
     # supporting multiple TLS versions is to use PROTOCOL_SSLv23 and
     # disable protocols via SSLContext.options and OP_NO_* constants.
     # However, SSLContext.options doesn't work unless we have the
     # full/real SSLContext available to us.
     if supportedprotocols == set(['tls1.0']):
         if protocol != 'tls1.0':
             raise error.Abort(_('current Python does not support protocol '
                                 'setting %s') % protocol,
                               hint=_('upgrade Python or disable setting since '
                                      'only TLS 1.0 is supported'))
 
         return ssl.PROTOCOL_TLSv1, 0, 'tls1.0'
 
     # WARNING: returned options don't work unless the modern ssl module
     # is available. Be careful when adding options here.
 
     # SSLv2 and SSLv3 are broken. We ban them outright.
     options = ssl.OP_NO_SSLv2 | ssl.OP_NO_SSLv3
 
     if protocol == 'tls1.0':
         # Defaults above are to use TLS 1.0+
         pass
     elif protocol == 'tls1.1':
         options |= ssl.OP_NO_TLSv1
     elif protocol == 'tls1.2':
         options |= ssl.OP_NO_TLSv1 | ssl.OP_NO_TLSv1_1
     else:
         raise error.Abort(_('this should not happen'))
 
     # Prevent CRIME.
     # There is no guarantee this attribute is defined on the module.
     options |= getattr(ssl, 'OP_NO_COMPRESSION', 0)
 
     return ssl.PROTOCOL_SSLv23, options, protocol
 
 def wrapsocket(sock, keyfile, certfile, ui, serverhostname=None):
     """Add SSL/TLS to a socket.
 
     This is a glorified wrapper for ``ssl.wrap_socket()``. It makes sane
     choices based on what security options are available.
 
     In addition to the arguments supported by ``ssl.wrap_socket``, we allow
     the following additional arguments:
 
     * serverhostname - The expected hostname of the remote server. If the
       server (and client) support SNI, this tells the server which certificate
       to use.
     """
     if not serverhostname:
         raise error.Abort(_('serverhostname argument is required'))
 
     settings = _hostsettings(ui, serverhostname)
 
     # We can't use ssl.create_default_context() because it calls
     # load_default_certs() unless CA arguments are passed to it. We want to
     # have explicit control over CA loading because implicitly loading
     # CAs may undermine the user's intent. For example, a user may define a CA
     # bundle with a specific CA cert removed. If the system/default CA bundle
     # is loaded and contains that removed CA, you've just undone the user's
     # choice.
     sslcontext = SSLContext(settings['protocol'])
 
     # This is a no-op unless using modern ssl.
     sslcontext.options |= settings['ctxoptions']
 
     # This still works on our fake SSLContext.
     sslcontext.verify_mode = settings['verifymode']
 
     if settings['ciphers']:
         try:
             sslcontext.set_ciphers(settings['ciphers'])
         except ssl.SSLError as e:
             raise error.Abort(_('could not set ciphers: %s') % e.args[0],
                               hint=_('change cipher string (%s) in config') %
                                    settings['ciphers'])
 
     if certfile is not None:
         def password():
             f = keyfile or certfile
             return ui.getpass(_('passphrase for %s: ') % f, '')
         sslcontext.load_cert_chain(certfile, keyfile, password)
 
     if settings['cafile'] is not None:
         try:
             sslcontext.load_verify_locations(cafile=settings['cafile'])
         except ssl.SSLError as e:
             if len(e.args) == 1: # pypy has different SSLError args
                 msg = e.args[0]
             else:
                 msg = e.args[1]
             raise error.Abort(_('error loading CA file %s: %s') % (
                               settings['cafile'], msg),
                               hint=_('file is empty or malformed?'))
         caloaded = True
     elif settings['allowloaddefaultcerts']:
         # This is a no-op on old Python.
         sslcontext.load_default_certs()
         caloaded = True
     else:
         caloaded = False
 
     try:
         sslsocket = sslcontext.wrap_socket(sock, server_hostname=serverhostname)
     except ssl.SSLError as e:
         # If we're doing certificate verification and no CA certs are loaded,
         # that is almost certainly the reason why verification failed. Provide
         # a hint to the user.
         # Only modern ssl module exposes SSLContext.get_ca_certs() so we can
         # only show this warning if modern ssl is available.
         # The exception handler is here because of
         # https://bugs.python.org/issue20916.
         try:
             if (caloaded and settings['verifymode'] == ssl.CERT_REQUIRED and
                 modernssl and not sslcontext.get_ca_certs()):
                 ui.warn(_('(an attempt was made to load CA certificates but '
                           'none were loaded; see '
                           'https://mercurial-scm.org/wiki/SecureConnections '
                           'for how to configure Mercurial to avoid this '
                           'error)\n'))
         except ssl.SSLError:
             pass
         # Try to print more helpful error messages for known failures.
         if util.safehasattr(e, 'reason'):
             # This error occurs when the client and server don't share a
             # common/supported SSL/TLS protocol. We've disabled SSLv2 and SSLv3
             # outright. Hopefully the reason for this error is that we require
             # TLS 1.1+ and the server only supports TLS 1.0. Whatever the
             # reason, try to emit an actionable warning.
             if e.reason == 'UNSUPPORTED_PROTOCOL':
                 # We attempted TLS 1.0+.
                 if settings['protocolui'] == 'tls1.0':
                     # We support more than just TLS 1.0+. If this happens,
                     # the likely scenario is either the client or the server
                     # is really old. (e.g. server doesn't support TLS 1.0+ or
                     # client doesn't support modern TLS versions introduced
                     # several years from when this comment was written).
                     if supportedprotocols != set(['tls1.0']):
                         ui.warn(_(
                             '(could not communicate with %s using security '
                             'protocols %s; if you are using a modern Mercurial '
                             'version, consider contacting the operator of this '
                             'server; see '
                             'https://mercurial-scm.org/wiki/SecureConnections '
                             'for more info)\n') % (
                                 serverhostname,
                                 ', '.join(sorted(supportedprotocols))))
                     else:
                         ui.warn(_(
                             '(could not communicate with %s using TLS 1.0; the '
                             'likely cause of this is the server no longer '
                             'supports TLS 1.0 because it has known security '
                             'vulnerabilities; see '
                             'https://mercurial-scm.org/wiki/SecureConnections '
                             'for more info)\n') % serverhostname)
                 else:
                     # We attempted TLS 1.1+. We can only get here if the client
                     # supports the configured protocol. So the likely reason is
                     # the client wants better security than the server can
                     # offer.
                     ui.warn(_(
                         '(could not negotiate a common security protocol (%s+) '
                         'with %s; the likely cause is Mercurial is configured '
                         'to be more secure than the server can support)\n') % (
                         settings['protocolui'], serverhostname))
                     ui.warn(_('(consider contacting the operator of this '
                               'server and ask them to support modern TLS '
                               'protocol versions; or, set '
                               'hostsecurity.%s:minimumprotocol=tls1.0 to allow '
                               'use of legacy, less secure protocols when '
                               'communicating with this server)\n') %
                             serverhostname)
                     ui.warn(_(
                         '(see https://mercurial-scm.org/wiki/SecureConnections '
                         'for more info)\n'))
         raise
 
     # check if wrap_socket failed silently because socket had been
     # closed
     # - see http://bugs.python.org/issue13721
     if not sslsocket.cipher():
         raise error.Abort(_('ssl connection failed'))
 
     sslsocket._hgstate = {
         'caloaded': caloaded,
         'hostname': serverhostname,
         'settings': settings,
         'ui': ui,
     }
 
     return sslsocket
 
 def wrapserversocket(sock, ui, certfile=None, keyfile=None, cafile=None,
                      requireclientcert=False):
     """Wrap a socket for use by servers.
 
     ``certfile`` and ``keyfile`` specify the files containing the certificate's
     public and private keys, respectively. Both keys can be defined in the same
     file via ``certfile`` (the private key must come first in the file).
 
     ``cafile`` defines the path to certificate authorities.
 
     ``requireclientcert`` specifies whether to require client certificates.
 
     Typically ``cafile`` is only defined if ``requireclientcert`` is true.
     """
     protocol, options, _protocolui = protocolsettings('tls1.0')
 
     # This config option is intended for use in tests only. It is a giant
     # footgun to kill security. Don't define it.
     exactprotocol = ui.config('devel', 'serverexactprotocol')
     if exactprotocol == 'tls1.0':
         protocol = ssl.PROTOCOL_TLSv1
     elif exactprotocol == 'tls1.1':
         if 'tls1.1' not in supportedprotocols:
             raise error.Abort(_('TLS 1.1 not supported by this Python'))
         protocol = ssl.PROTOCOL_TLSv1_1
     elif exactprotocol == 'tls1.2':
         if 'tls1.2' not in supportedprotocols:
             raise error.Abort(_('TLS 1.2 not supported by this Python'))
         protocol = ssl.PROTOCOL_TLSv1_2
     elif exactprotocol:
         raise error.Abort(_('invalid value for serverexactprotocol: %s') %
                           exactprotocol)
 
     if modernssl:
         # We /could/ use create_default_context() here since it doesn't load
         # CAs when configured for client auth. However, it is hard-coded to
         # use ssl.PROTOCOL_SSLv23 which may not be appropriate here.
         sslcontext = SSLContext(protocol)
         sslcontext.options |= options
 
         # Improve forward secrecy.
         sslcontext.options |= getattr(ssl, 'OP_SINGLE_DH_USE', 0)
         sslcontext.options |= getattr(ssl, 'OP_SINGLE_ECDH_USE', 0)
 
         # Use the list of more secure ciphers if found in the ssl module.
         if util.safehasattr(ssl, '_RESTRICTED_SERVER_CIPHERS'):
             sslcontext.options |= getattr(ssl, 'OP_CIPHER_SERVER_PREFERENCE', 0)
             sslcontext.set_ciphers(ssl._RESTRICTED_SERVER_CIPHERS)
     else:
         sslcontext = SSLContext(ssl.PROTOCOL_TLSv1)
 
     if requireclientcert:
         sslcontext.verify_mode = ssl.CERT_REQUIRED
     else:
         sslcontext.verify_mode = ssl.CERT_NONE
 
     if certfile or keyfile:
         sslcontext.load_cert_chain(certfile=certfile, keyfile=keyfile)
 
     if cafile:
         sslcontext.load_verify_locations(cafile=cafile)
 
     return sslcontext.wrap_socket(sock, server_side=True)
 
 class wildcarderror(Exception):
     """Represents an error parsing wildcards in DNS name."""
 
 def _dnsnamematch(dn, hostname, maxwildcards=1):
     """Match DNS names according RFC 6125 section 6.4.3.
 
     This code is effectively copied from CPython's ssl._dnsname_match.
 
     Returns a bool indicating whether the expected hostname matches
     the value in ``dn``.
     """
     pats = []
     if not dn:
         return False
 
     pieces = dn.split(r'.')
     leftmost = pieces[0]
     remainder = pieces[1:]
     wildcards = leftmost.count('*')
     if wildcards > maxwildcards:
         raise wildcarderror(
             _('too many wildcards in certificate DNS name: %s') % dn)
 
     # speed up common case w/o wildcards
     if not wildcards:
         return dn.lower() == hostname.lower()
 
     # RFC 6125, section 6.4.3, subitem 1.
     # The client SHOULD NOT attempt to match a presented identifier in which
     # the wildcard character comprises a label other than the left-most label.
     if leftmost == '*':
         # When '*' is a fragment by itself, it matches a non-empty dotless
         # fragment.
         pats.append('[^.]+')
     elif leftmost.startswith('xn--') or hostname.startswith('xn--'):
         # RFC 6125, section 6.4.3, subitem 3.
         # The client SHOULD NOT attempt to match a presented identifier
         # where the wildcard character is embedded within an A-label or
         # U-label of an internationalized domain name.
         pats.append(re.escape(leftmost))
     else:
         # Otherwise, '*' matches any dotless string, e.g. www*
         pats.append(re.escape(leftmost).replace(r'\*', '[^.]*'))
 
     # add the remaining fragments, ignore any wildcards
     for frag in remainder:
         pats.append(re.escape(frag))
 
     pat = re.compile(r'\A' + r'\.'.join(pats) + r'\Z', re.IGNORECASE)
     return pat.match(hostname) is not None
 
 def _verifycert(cert, hostname):
     '''Verify that cert (in socket.getpeercert() format) matches hostname.
     CRLs is not handled.
 
     Returns error message if any problems are found and None on success.
     '''
     if not cert:
         return _('no certificate received')
 
     dnsnames = []
     san = cert.get('subjectAltName', [])
     for key, value in san:
         if key == 'DNS':
             try:
                 if _dnsnamematch(value, hostname):
                     return
             except wildcarderror as e:
                 return e.args[0]
 
             dnsnames.append(value)
 
     if not dnsnames:
         # The subject is only checked when there is no DNS in subjectAltName.
         for sub in cert.get('subject', []):
             for key, value in sub:
                 # According to RFC 2818 the most specific Common Name must
                 # be used.
                 if key == 'commonName':
                     # 'subject' entries are unicode.
                     try:
                         value = value.encode('ascii')
                     except UnicodeEncodeError:
                         return _('IDN in certificate not supported')
 
                     try:
                         if _dnsnamematch(value, hostname):
                             return
                     except wildcarderror as e:
                         return e.args[0]
 
                     dnsnames.append(value)
 
     if len(dnsnames) > 1:
         return _('certificate is for %s') % ', '.join(dnsnames)
     elif len(dnsnames) == 1:
         return _('certificate is for %s') % dnsnames[0]
     else:
         return _('no commonName or subjectAltName found in certificate')
 
 def _plainapplepython():
     """return true if this seems to be a pure Apple Python that
     * is unfrozen and presumably has the whole mercurial module in the file
       system
     * presumably is an Apple Python that uses Apple OpenSSL which has patches
       for using system certificate store CAs in addition to the provided
       cacerts file
     """
     if (pycompat.sysplatform != 'darwin' or
-                        util.mainfrozen() or not sys.executable):
+                        util.mainfrozen() or not pycompat.sysexecutable):
         return False
-    exe = os.path.realpath(sys.executable).lower()
+    exe = os.path.realpath(pycompat.sysexecutable).lower()
     return (exe.startswith('/usr/bin/python') or
             exe.startswith('/system/library/frameworks/python.framework/'))
 
 _systemcacertpaths = [
     # RHEL, CentOS, and Fedora
     '/etc/pki/tls/certs/ca-bundle.trust.crt',
     # Debian, Ubuntu, Gentoo
     '/etc/ssl/certs/ca-certificates.crt',
 ]
 
 def _defaultcacerts(ui):
     """return path to default CA certificates or None.
 
     It is assumed this function is called when the returned certificates
     file will actually be used to validate connections. Therefore this
     function may print warnings or debug messages assuming this usage.
 
     We don't print a message when the Python is able to load default
     CA certs because this scenario is detected at socket connect time.
     """
     # The "certifi" Python package provides certificates. If it is installed
     # and usable, assume the user intends it to be used and use it.
     try:
         import certifi
         certs = certifi.where()
         if os.path.exists(certs):
             ui.debug('using ca certificates from certifi\n')
             return certs
     except (ImportError, AttributeError):
         pass
 
     # On Windows, only the modern ssl module is capable of loading the system
     # CA certificates. If we're not capable of doing that, emit a warning
     # because we'll get a certificate verification error later and the lack
     # of loaded CA certificates will be the reason why.
     # Assertion: this code is only called if certificates are being verified.
     if pycompat.osname == 'nt':
         if not _canloaddefaultcerts:
             ui.warn(_('(unable to load Windows CA certificates; see '
                       'https://mercurial-scm.org/wiki/SecureConnections for '
                       'how to configure Mercurial to avoid this message)\n'))
 
         return None
 
     # Apple's OpenSSL has patches that allow a specially constructed certificate
     # to load the system CA store. If we're running on Apple Python, use this
     # trick.
     if _plainapplepython():
         dummycert = os.path.join(os.path.dirname(__file__), 'dummycert.pem')
         if os.path.exists(dummycert):
             return dummycert
 
     # The Apple OpenSSL trick isn't available to us. If Python isn't able to
     # load system certs, we're out of luck.
     if pycompat.sysplatform == 'darwin':
         # FUTURE Consider looking for Homebrew or MacPorts installed certs
         # files. Also consider exporting the keychain certs to a file during
         # Mercurial install.
         if not _canloaddefaultcerts:
             ui.warn(_('(unable to load CA certificates; see '
                       'https://mercurial-scm.org/wiki/SecureConnections for '
                       'how to configure Mercurial to avoid this message)\n'))
         return None
 
     # / is writable on Windows. Out of an abundance of caution make sure
     # we're not on Windows because paths from _systemcacerts could be installed
     # by non-admin users.
     assert pycompat.osname != 'nt'
 
     # Try to find CA certificates in well-known locations. We print a warning
     # when using a found file because we don't want too much silent magic
     # for security settings. The expectation is that proper Mercurial
     # installs will have the CA certs path defined at install time and the
     # installer/packager will make an appropriate decision on the user's
     # behalf. We only get here and perform this setting as a feature of
     # last resort.
     if not _canloaddefaultcerts:
         for path in _systemcacertpaths:
             if os.path.isfile(path):
                 ui.warn(_('(using CA certificates from %s; if you see this '
                           'message, your Mercurial install is not properly '
                           'configured; see '
                           'https://mercurial-scm.org/wiki/SecureConnections '
                           'for how to configure Mercurial to avoid this '
                           'message)\n') % path)
                 return path
 
         ui.warn(_('(unable to load CA certificates; see '
                   'https://mercurial-scm.org/wiki/SecureConnections for '
                   'how to configure Mercurial to avoid this message)\n'))
 
     return None
 
 def validatesocket(sock):
     """Validate a socket meets security requirements.
 
     The passed socket must have been created with ``wrapsocket()``.
     """
     host = sock._hgstate['hostname']
     ui = sock._hgstate['ui']
     settings = sock._hgstate['settings']
 
     try:
         peercert = sock.getpeercert(True)
         peercert2 = sock.getpeercert()
     except AttributeError:
         raise error.Abort(_('%s ssl connection error') % host)
 
     if not peercert:
         raise error.Abort(_('%s certificate error: '
                            'no certificate received') % host)
 
     if settings['disablecertverification']:
         # We don't print the certificate fingerprint because it shouldn't
         # be necessary: if the user requested certificate verification be
         # disabled, they presumably already saw a message about the inability
         # to verify the certificate and this message would have printed the
         # fingerprint. So printing the fingerprint here adds little to no
         # value.
         ui.warn(_('warning: connection security to %s is disabled per current '
                   'settings; communication is susceptible to eavesdropping '
                   'and tampering\n') % host)
         return
 
     # If a certificate fingerprint is pinned, use it and only it to
     # validate the remote cert.
     peerfingerprints = {
         'sha1': hashlib.sha1(peercert).hexdigest(),
         'sha256': hashlib.sha256(peercert).hexdigest(),
         'sha512': hashlib.sha512(peercert).hexdigest(),
     }
 
     def fmtfingerprint(s):
         return ':'.join([s[x:x + 2] for x in range(0, len(s), 2)])
 
     nicefingerprint = 'sha256:%s' % fmtfingerprint(peerfingerprints['sha256'])
 
     if settings['certfingerprints']:
         for hash, fingerprint in settings['certfingerprints']:
             if peerfingerprints[hash].lower() == fingerprint:
                 ui.debug('%s certificate matched fingerprint %s:%s\n' %
                          (host, hash, fmtfingerprint(fingerprint)))
                 return
 
         # Pinned fingerprint didn't match. This is a fatal error.
         if settings['legacyfingerprint']:
             section = 'hostfingerprint'
             nice = fmtfingerprint(peerfingerprints['sha1'])
         else:
             section = 'hostsecurity'
             nice = '%s:%s' % (hash, fmtfingerprint(peerfingerprints[hash]))
         raise error.Abort(_('certificate for %s has unexpected '
                             'fingerprint %s') % (host, nice),
                           hint=_('check %s configuration') % section)
 
     # Security is enabled but no CAs are loaded. We can't establish trust
     # for the cert so abort.
     if not sock._hgstate['caloaded']:
         raise error.Abort(
             _('unable to verify security of %s (no loaded CA certificates); '
               'refusing to connect') % host,
             hint=_('see https://mercurial-scm.org/wiki/SecureConnections for '
                    'how to configure Mercurial to avoid this error or set '
                    'hostsecurity.%s:fingerprints=%s to trust this server') %
                    (host, nicefingerprint))
 
     msg = _verifycert(peercert2, host)
     if msg:
         raise error.Abort(_('%s certificate error: %s') % (host, msg),
                          hint=_('set hostsecurity.%s:certfingerprints=%s '
                                 'config setting or use --insecure to connect '
                                 'insecurely') %
                               (host, nicefingerprint))

mercurial/util.py

@@ -1,3246 +1,3246
 # util.py - Mercurial utility functions and platform specific implementations
 #
 #  Copyright 2005 K. Thananchayan <[e-mail]>
 #  Copyright 2005-2007 Matt Mackall <[e-mail]>
 #  Copyright 2006 Vadim Gelfer <[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.
 
 """Mercurial utility functions and platform specific implementations.
 
 This contains helper routines that are independent of the SCM core and
 hide platform-specific details from the core.
 """
 
 from __future__ import absolute_import
 
 import bz2
 import calendar
 import collections
 import datetime
 import errno
 import gc
 import hashlib
 import imp
 import os
 import platform as pyplatform
 import re as remod
 import shutil
 import signal
 import socket
 import stat
 import string
 import subprocess
 import sys
 import tempfile
 import textwrap
 import time
 import traceback
 import zlib
 
 from . import (
     encoding,
     error,
     i18n,
     osutil,
     parsers,
     pycompat,
 )
 
 empty = pycompat.empty
 httplib = pycompat.httplib
 httpserver = pycompat.httpserver
 pickle = pycompat.pickle
 queue = pycompat.queue
 socketserver = pycompat.socketserver
 stderr = pycompat.stderr
 stdin = pycompat.stdin
 stdout = pycompat.stdout
 stringio = pycompat.stringio
 urlerr = pycompat.urlerr
 urlparse = pycompat.urlparse
 urlreq = pycompat.urlreq
 xmlrpclib = pycompat.xmlrpclib
 
 if pycompat.osname == 'nt':
     from . import windows as platform
     stdout = platform.winstdout(pycompat.stdout)
 else:
     from . import posix as platform
 
 _ = i18n._
 
 bindunixsocket = platform.bindunixsocket
 cachestat = platform.cachestat
 checkexec = platform.checkexec
 checklink = platform.checklink
 copymode = platform.copymode
 executablepath = platform.executablepath
 expandglobs = platform.expandglobs
 explainexit = platform.explainexit
 findexe = platform.findexe
 gethgcmd = platform.gethgcmd
 getuser = platform.getuser
 getpid = os.getpid
 groupmembers = platform.groupmembers
 groupname = platform.groupname
 hidewindow = platform.hidewindow
 isexec = platform.isexec
 isowner = platform.isowner
 localpath = platform.localpath
 lookupreg = platform.lookupreg
 makedir = platform.makedir
 nlinks = platform.nlinks
 normpath = platform.normpath
 normcase = platform.normcase
 normcasespec = platform.normcasespec
 normcasefallback = platform.normcasefallback
 openhardlinks = platform.openhardlinks
 oslink = platform.oslink
 parsepatchoutput = platform.parsepatchoutput
 pconvert = platform.pconvert
 poll = platform.poll
 popen = platform.popen
 posixfile = platform.posixfile
 quotecommand = platform.quotecommand
 readpipe = platform.readpipe
 rename = platform.rename
 removedirs = platform.removedirs
 samedevice = platform.samedevice
 samefile = platform.samefile
 samestat = platform.samestat
 setbinary = platform.setbinary
 setflags = platform.setflags
 setsignalhandler = platform.setsignalhandler
 shellquote = platform.shellquote
 spawndetached = platform.spawndetached
 split = platform.split
 sshargs = platform.sshargs
 statfiles = getattr(osutil, 'statfiles', platform.statfiles)
 statisexec = platform.statisexec
 statislink = platform.statislink
 testpid = platform.testpid
 umask = platform.umask
 unlink = platform.unlink
 unlinkpath = platform.unlinkpath
 username = platform.username
 
 # Python compatibility
 
 _notset = object()
 
 # disable Python's problematic floating point timestamps (issue4836)
 # (Python hypocritically says you shouldn't change this behavior in
 # libraries, and sure enough Mercurial is not a library.)
 os.stat_float_times(False)
 
 def safehasattr(thing, attr):
     return getattr(thing, attr, _notset) is not _notset
 
 DIGESTS = {
     'md5': hashlib.md5,
     'sha1': hashlib.sha1,
     'sha512': hashlib.sha512,
 }
 # List of digest types from strongest to weakest
 DIGESTS_BY_STRENGTH = ['sha512', 'sha1', 'md5']
 
 for k in DIGESTS_BY_STRENGTH:
     assert k in DIGESTS
 
 class digester(object):
     """helper to compute digests.
 
     This helper can be used to compute one or more digests given their name.
 
     >>> d = digester(['md5', 'sha1'])
     >>> d.update('foo')
     >>> [k for k in sorted(d)]
     ['md5', 'sha1']
     >>> d['md5']
     'acbd18db4cc2f85cedef654fccc4a4d8'
     >>> d['sha1']
     '0beec7b5ea3f0fdbc95d0dd47f3c5bc275da8a33'
     >>> digester.preferred(['md5', 'sha1'])
     'sha1'
     """
 
     def __init__(self, digests, s=''):
         self._hashes = {}
         for k in digests:
             if k not in DIGESTS:
                 raise Abort(_('unknown digest type: %s') % k)
             self._hashes[k] = DIGESTS[k]()
         if s:
             self.update(s)
 
     def update(self, data):
         for h in self._hashes.values():
             h.update(data)
 
     def __getitem__(self, key):
         if key not in DIGESTS:
             raise Abort(_('unknown digest type: %s') % k)
         return self._hashes[key].hexdigest()
 
     def __iter__(self):
         return iter(self._hashes)
 
     @staticmethod
     def preferred(supported):
         """returns the strongest digest type in both supported and DIGESTS."""
 
         for k in DIGESTS_BY_STRENGTH:
             if k in supported:
                 return k
         return None
 
 class digestchecker(object):
     """file handle wrapper that additionally checks content against a given
     size and digests.
 
         d = digestchecker(fh, size, {'md5': '...'})
 
     When multiple digests are given, all of them are validated.
     """
 
     def __init__(self, fh, size, digests):
         self._fh = fh
         self._size = size
         self._got = 0
         self._digests = dict(digests)
         self._digester = digester(self._digests.keys())
 
     def read(self, length=-1):
         content = self._fh.read(length)
         self._digester.update(content)
         self._got += len(content)
         return content
 
     def validate(self):
         if self._size != self._got:
             raise Abort(_('size mismatch: expected %d, got %d') %
                 (self._size, self._got))
         for k, v in self._digests.items():
             if v != self._digester[k]:
                 # i18n: first parameter is a digest name
                 raise Abort(_('%s mismatch: expected %s, got %s') %
                     (k, v, self._digester[k]))
 
 try:
     buffer = buffer
 except NameError:
     if not pycompat.ispy3:
         def buffer(sliceable, offset=0):
             return sliceable[offset:]
     else:
         def buffer(sliceable, offset=0):
             return memoryview(sliceable)[offset:]
 
 closefds = pycompat.osname == 'posix'
 
 _chunksize = 4096
 
 class bufferedinputpipe(object):
     """a manually buffered input pipe
 
     Python will not let us use buffered IO and lazy reading with 'polling' at
     the same time. We cannot probe the buffer state and select will not detect
     that data are ready to read if they are already buffered.
 
     This class let us work around that by implementing its own buffering
     (allowing efficient readline) while offering a way to know if the buffer is
     empty from the output (allowing collaboration of the buffer with polling).
 
     This class lives in the 'util' module because it makes use of the 'os'
     module from the python stdlib.
     """
 
     def __init__(self, input):
         self._input = input
         self._buffer = []
         self._eof = False
         self._lenbuf = 0
 
     @property
     def hasbuffer(self):
         """True is any data is currently buffered
 
         This will be used externally a pre-step for polling IO. If there is
         already data then no polling should be set in place."""
         return bool(self._buffer)
 
     @property
     def closed(self):
         return self._input.closed
 
     def fileno(self):
         return self._input.fileno()
 
     def close(self):
         return self._input.close()
 
     def read(self, size):
         while (not self._eof) and (self._lenbuf < size):
             self._fillbuffer()
         return self._frombuffer(size)
 
     def readline(self, *args, **kwargs):
         if 1 < len(self._buffer):
             # this should not happen because both read and readline end with a
             # _frombuffer call that collapse it.
             self._buffer = [''.join(self._buffer)]
             self._lenbuf = len(self._buffer[0])
         lfi = -1
         if self._buffer:
             lfi = self._buffer[-1].find('\n')
         while (not self._eof) and lfi < 0:
             self._fillbuffer()
             if self._buffer:
                 lfi = self._buffer[-1].find('\n')
         size = lfi + 1
         if lfi < 0: # end of file
             size = self._lenbuf
         elif 1 < len(self._buffer):
             # we need to take previous chunks into account
             size += self._lenbuf - len(self._buffer[-1])
         return self._frombuffer(size)
 
     def _frombuffer(self, size):
         """return at most 'size' data from the buffer
 
         The data are removed from the buffer."""
         if size == 0 or not self._buffer:
             return ''
         buf = self._buffer[0]
         if 1 < len(self._buffer):
             buf = ''.join(self._buffer)
 
         data = buf[:size]
         buf = buf[len(data):]
         if buf:
             self._buffer = [buf]
             self._lenbuf = len(buf)
         else:
             self._buffer = []
             self._lenbuf = 0
         return data
 
     def _fillbuffer(self):
         """read data to the buffer"""
         data = os.read(self._input.fileno(), _chunksize)
         if not data:
             self._eof = True
         else:
             self._lenbuf += len(data)
             self._buffer.append(data)
 
 def popen2(cmd, env=None, newlines=False):
     # Setting bufsize to -1 lets the system decide the buffer size.
     # The default for bufsize is 0, meaning unbuffered. This leads to
     # poor performance on Mac OS X: http://bugs.python.org/issue4194
     p = subprocess.Popen(cmd, shell=True, bufsize=-1,
                          close_fds=closefds,
                          stdin=subprocess.PIPE, stdout=subprocess.PIPE,
                          universal_newlines=newlines,
                          env=env)
     return p.stdin, p.stdout
 
 def popen3(cmd, env=None, newlines=False):
     stdin, stdout, stderr, p = popen4(cmd, env, newlines)
     return stdin, stdout, stderr
 
 def popen4(cmd, env=None, newlines=False, bufsize=-1):
     p = subprocess.Popen(cmd, shell=True, bufsize=bufsize,
                          close_fds=closefds,
                          stdin=subprocess.PIPE, stdout=subprocess.PIPE,
                          stderr=subprocess.PIPE,
                          universal_newlines=newlines,
                          env=env)
     return p.stdin, p.stdout, p.stderr, p
 
 def version():
     """Return version information if available."""
     try:
         from . import __version__
         return __version__.version
     except ImportError:
         return 'unknown'
 
 def versiontuple(v=None, n=4):
     """Parses a Mercurial version string into an N-tuple.
 
     The version string to be parsed is specified with the ``v`` argument.
     If it isn't defined, the current Mercurial version string will be parsed.
 
     ``n`` can be 2, 3, or 4. Here is how some version strings map to
     returned values:
 
     >>> v = '3.6.1+190-df9b73d2d444'
     >>> versiontuple(v, 2)
     (3, 6)
     >>> versiontuple(v, 3)
     (3, 6, 1)
     >>> versiontuple(v, 4)
     (3, 6, 1, '190-df9b73d2d444')
 
     >>> versiontuple('3.6.1+190-df9b73d2d444+20151118')
     (3, 6, 1, '190-df9b73d2d444+20151118')
 
     >>> v = '3.6'
     >>> versiontuple(v, 2)
     (3, 6)
     >>> versiontuple(v, 3)
     (3, 6, None)
     >>> versiontuple(v, 4)
     (3, 6, None, None)
 
     >>> v = '3.9-rc'
     >>> versiontuple(v, 2)
     (3, 9)
     >>> versiontuple(v, 3)
     (3, 9, None)
     >>> versiontuple(v, 4)
     (3, 9, None, 'rc')
 
     >>> v = '3.9-rc+2-02a8fea4289b'
     >>> versiontuple(v, 2)
     (3, 9)
     >>> versiontuple(v, 3)
     (3, 9, None)
     >>> versiontuple(v, 4)
     (3, 9, None, 'rc+2-02a8fea4289b')
     """
     if not v:
         v = version()
     parts = remod.split('[\+-]', v, 1)
     if len(parts) == 1:
         vparts, extra = parts[0], None
     else:
         vparts, extra = parts
 
     vints = []
     for i in vparts.split('.'):
         try:
             vints.append(int(i))
         except ValueError:
             break
     # (3, 6) -> (3, 6, None)
     while len(vints) < 3:
         vints.append(None)
 
     if n == 2:
         return (vints[0], vints[1])
     if n == 3:
         return (vints[0], vints[1], vints[2])
     if n == 4:
         return (vints[0], vints[1], vints[2], extra)
 
 # used by parsedate
 defaultdateformats = (
     '%Y-%m-%dT%H:%M:%S', # the 'real' ISO8601
     '%Y-%m-%dT%H:%M',    #   without seconds
     '%Y-%m-%dT%H%M%S',   # another awful but legal variant without :
     '%Y-%m-%dT%H%M',     #   without seconds
     '%Y-%m-%d %H:%M:%S', # our common legal variant
     '%Y-%m-%d %H:%M',    #   without seconds
     '%Y-%m-%d %H%M%S',   # without :
     '%Y-%m-%d %H%M',     #   without seconds
     '%Y-%m-%d %I:%M:%S%p',
     '%Y-%m-%d %H:%M',
     '%Y-%m-%d %I:%M%p',
     '%Y-%m-%d',
     '%m-%d',
     '%m/%d',
     '%m/%d/%y',
     '%m/%d/%Y',
     '%a %b %d %H:%M:%S %Y',
     '%a %b %d %I:%M:%S%p %Y',
     '%a, %d %b %Y %H:%M:%S',        #  GNU coreutils "/bin/date --rfc-2822"
     '%b %d %H:%M:%S %Y',
     '%b %d %I:%M:%S%p %Y',
     '%b %d %H:%M:%S',
     '%b %d %I:%M:%S%p',
     '%b %d %H:%M',
     '%b %d %I:%M%p',
     '%b %d %Y',
     '%b %d',
     '%H:%M:%S',
     '%I:%M:%S%p',
     '%H:%M',
     '%I:%M%p',
 )
 
 extendeddateformats = defaultdateformats + (
     "%Y",
     "%Y-%m",
     "%b",
     "%b %Y",
     )
 
 def cachefunc(func):
     '''cache the result of function calls'''
     # XXX doesn't handle keywords args
     if func.__code__.co_argcount == 0:
         cache = []
         def f():
             if len(cache) == 0:
                 cache.append(func())
             return cache[0]
         return f
     cache = {}
     if func.__code__.co_argcount == 1:
         # we gain a small amount of time because
         # we don't need to pack/unpack the list
         def f(arg):
             if arg not in cache:
                 cache[arg] = func(arg)
             return cache[arg]
     else:
         def f(*args):
             if args not in cache:
                 cache[args] = func(*args)
             return cache[args]
 
     return f
 
 class sortdict(dict):
     '''a simple sorted dictionary'''
     def __init__(self, data=None):
         self._list = []
         if data:
             self.update(data)
     def copy(self):
         return sortdict(self)
     def __setitem__(self, key, val):
         if key in self:
             self._list.remove(key)
         self._list.append(key)
         dict.__setitem__(self, key, val)
     def __iter__(self):
         return self._list.__iter__()
     def update(self, src):
         if isinstance(src, dict):
             src = src.iteritems()
         for k, v in src:
             self[k] = v
     def clear(self):
         dict.clear(self)
         self._list = []
     def items(self):
         return [(k, self[k]) for k in self._list]
     def __delitem__(self, key):
         dict.__delitem__(self, key)
         self._list.remove(key)
     def pop(self, key, *args, **kwargs):
         dict.pop(self, key, *args, **kwargs)
         try:
             self._list.remove(key)
         except ValueError:
             pass
     def keys(self):
         return self._list
     def iterkeys(self):
         return self._list.__iter__()
     def iteritems(self):
         for k in self._list:
             yield k, self[k]
     def insert(self, index, key, val):
         self._list.insert(index, key)
         dict.__setitem__(self, key, val)
     def __repr__(self):
         if not self:
             return '%s()' % self.__class__.__name__
         return '%s(%r)' % (self.__class__.__name__, self.items())
 
 class _lrucachenode(object):
     """A node in a doubly linked list.
 
     Holds a reference to nodes on either side as well as a key-value
     pair for the dictionary entry.
     """
     __slots__ = (u'next', u'prev', u'key', u'value')
 
     def __init__(self):
         self.next = None
         self.prev = None
 
         self.key = _notset
         self.value = None
 
     def markempty(self):
         """Mark the node as emptied."""
         self.key = _notset
 
 class lrucachedict(object):
     """Dict that caches most recent accesses and sets.
 
     The dict consists of an actual backing dict - indexed by original
     key - and a doubly linked circular list defining the order of entries in
     the cache.
 
     The head node is the newest entry in the cache. If the cache is full,
     we recycle head.prev and make it the new head. Cache accesses result in
     the node being moved to before the existing head and being marked as the
     new head node.
     """
     def __init__(self, max):
         self._cache = {}
 
         self._head = head = _lrucachenode()
         head.prev = head
         head.next = head
         self._size = 1
         self._capacity = max
 
     def __len__(self):
         return len(self._cache)
 
     def __contains__(self, k):
         return k in self._cache
 
     def __iter__(self):
         # We don't have to iterate in cache order, but why not.
         n = self._head
         for i in range(len(self._cache)):
             yield n.key
             n = n.next
 
     def __getitem__(self, k):
         node = self._cache[k]
         self._movetohead(node)
         return node.value
 
     def __setitem__(self, k, v):
         node = self._cache.get(k)
         # Replace existing value and mark as newest.
         if node is not None:
             node.value = v
             self._movetohead(node)
             return
 
         if self._size < self._capacity:
             node = self._addcapacity()
         else:
             # Grab the last/oldest item.
             node = self._head.prev
 
         # At capacity. Kill the old entry.
         if node.key is not _notset:
             del self._cache[node.key]
 
         node.key = k
         node.value = v
         self._cache[k] = node
         # And mark it as newest entry. No need to adjust order since it
         # is already self._head.prev.
         self._head = node
 
     def __delitem__(self, k):
         node = self._cache.pop(k)
         node.markempty()
 
         # Temporarily mark as newest item before re-adjusting head to make
         # this node the oldest item.
         self._movetohead(node)
         self._head = node.next
 
     # Additional dict methods.
 
     def get(self, k, default=None):
         try:
             return self._cache[k].value
         except KeyError:
             return default
 
     def clear(self):
         n = self._head
         while n.key is not _notset:
             n.markempty()
             n = n.next
 
         self._cache.clear()
 
     def copy(self):
         result = lrucachedict(self._capacity)
         n = self._head.prev
         # Iterate in oldest-to-newest order, so the copy has the right ordering
         for i in range(len(self._cache)):
             result[n.key] = n.value
             n = n.prev
         return result
 
     def _movetohead(self, node):
         """Mark a node as the newest, making it the new head.
 
         When a node is accessed, it becomes the freshest entry in the LRU
         list, which is denoted by self._head.
 
         Visually, let's make ``N`` the new head node (* denotes head):
 
             previous/oldest <-> head <-> next/next newest
 
             ----<->--- A* ---<->-----
             |                       |
             E <-> D <-> N <-> C <-> B
 
         To:
 
             ----<->--- N* ---<->-----
             |                       |
             E <-> D <-> C <-> B <-> A
 
         This requires the following moves:
 
            C.next = D  (node.prev.next = node.next)
            D.prev = C  (node.next.prev = node.prev)
            E.next = N  (head.prev.next = node)
            N.prev = E  (node.prev = head.prev)
            N.next = A  (node.next = head)
            A.prev = N  (head.prev = node)
         """
         head = self._head
         # C.next = D
         node.prev.next = node.next
         # D.prev = C
         node.next.prev = node.prev
         # N.prev = E
         node.prev = head.prev
         # N.next = A
         # It is tempting to do just "head" here, however if node is
         # adjacent to head, this will do bad things.
         node.next = head.prev.next
         # E.next = N
         node.next.prev = node
         # A.prev = N
         node.prev.next = node
 
         self._head = node
 
     def _addcapacity(self):
         """Add a node to the circular linked list.
 
         The new node is inserted before the head node.
         """
         head = self._head
         node = _lrucachenode()
         head.prev.next = node
         node.prev = head.prev
         node.next = head
         head.prev = node
         self._size += 1
         return node
 
 def lrucachefunc(func):
     '''cache most recent results of function calls'''
     cache = {}
     order = collections.deque()
     if func.__code__.co_argcount == 1:
         def f(arg):
             if arg not in cache:
                 if len(cache) > 20:
                     del cache[order.popleft()]
                 cache[arg] = func(arg)
             else:
                 order.remove(arg)
             order.append(arg)
             return cache[arg]
     else:
         def f(*args):
             if args not in cache:
                 if len(cache) > 20:
                     del cache[order.popleft()]
                 cache[args] = func(*args)
             else:
                 order.remove(args)
             order.append(args)
             return cache[args]
 
     return f
 
 class propertycache(object):
     def __init__(self, func):
         self.func = func
         self.name = func.__name__
     def __get__(self, obj, type=None):
         result = self.func(obj)
         self.cachevalue(obj, result)
         return result
 
     def cachevalue(self, obj, value):
         # __dict__ assignment required to bypass __setattr__ (eg: repoview)
         obj.__dict__[self.name] = value
 
 def pipefilter(s, cmd):
     '''filter string S through command CMD, returning its output'''
     p = subprocess.Popen(cmd, shell=True, close_fds=closefds,
                          stdin=subprocess.PIPE, stdout=subprocess.PIPE)
     pout, perr = p.communicate(s)
     return pout
 
 def tempfilter(s, cmd):
     '''filter string S through a pair of temporary files with CMD.
     CMD is used as a template to create the real command to be run,
     with the strings INFILE and OUTFILE replaced by the real names of
     the temporary files generated.'''
     inname, outname = None, None
     try:
         infd, inname = tempfile.mkstemp(prefix='hg-filter-in-')
         fp = os.fdopen(infd, 'wb')
         fp.write(s)
         fp.close()
         outfd, outname = tempfile.mkstemp(prefix='hg-filter-out-')
         os.close(outfd)
         cmd = cmd.replace('INFILE', inname)
         cmd = cmd.replace('OUTFILE', outname)
         code = os.system(cmd)
         if pycompat.sysplatform == 'OpenVMS' and code & 1:
             code = 0
         if code:
             raise Abort(_("command '%s' failed: %s") %
                         (cmd, explainexit(code)))
         return readfile(outname)
     finally:
         try:
             if inname:
                 os.unlink(inname)
         except OSError:
             pass
         try:
             if outname:
                 os.unlink(outname)
         except OSError:
             pass
 
 filtertable = {
     'tempfile:': tempfilter,
     'pipe:': pipefilter,
     }
 
 def filter(s, cmd):
     "filter a string through a command that transforms its input to its output"
     for name, fn in filtertable.iteritems():
         if cmd.startswith(name):
             return fn(s, cmd[len(name):].lstrip())
     return pipefilter(s, cmd)
 
 def binary(s):
     """return true if a string is binary data"""
     return bool(s and '\0' in s)
 
 def increasingchunks(source, min=1024, max=65536):
     '''return no less than min bytes per chunk while data remains,
     doubling min after each chunk until it reaches max'''
     def log2(x):
         if not x:
             return 0
         i = 0
         while x:
             x >>= 1
             i += 1
         return i - 1
 
     buf = []
     blen = 0
     for chunk in source:
         buf.append(chunk)
         blen += len(chunk)
         if blen >= min:
             if min < max:
                 min = min << 1
                 nmin = 1 << log2(blen)
                 if nmin > min:
                     min = nmin
                 if min > max:
                     min = max
             yield ''.join(buf)
             blen = 0
             buf = []
     if buf:
         yield ''.join(buf)
 
 Abort = error.Abort
 
 def always(fn):
     return True
 
 def never(fn):
     return False
 
 def nogc(func):
     """disable garbage collector
 
     Python's garbage collector triggers a GC each time a certain number of
     container objects (the number being defined by gc.get_threshold()) are
     allocated even when marked not to be tracked by the collector. Tracking has
     no effect on when GCs are triggered, only on what objects the GC looks
     into. As a workaround, disable GC while building complex (huge)
     containers.
 
     This garbage collector issue have been fixed in 2.7.
     """
     if sys.version_info >= (2, 7):
         return func
     def wrapper(*args, **kwargs):
         gcenabled = gc.isenabled()
         gc.disable()
         try:
             return func(*args, **kwargs)
         finally:
             if gcenabled:
                 gc.enable()
     return wrapper
 
 def pathto(root, n1, n2):
     '''return the relative path from one place to another.
     root should use os.sep to separate directories
     n1 should use os.sep to separate directories
     n2 should use "/" to separate directories
     returns an os.sep-separated path.
 
     If n1 is a relative path, it's assumed it's
     relative to root.
     n2 should always be relative to root.
     '''
     if not n1:
         return localpath(n2)
     if os.path.isabs(n1):
         if os.path.splitdrive(root)[0] != os.path.splitdrive(n1)[0]:
             return os.path.join(root, localpath(n2))
         n2 = '/'.join((pconvert(root), n2))
     a, b = splitpath(n1), n2.split('/')
     a.reverse()
     b.reverse()
     while a and b and a[-1] == b[-1]:
         a.pop()
         b.pop()
     b.reverse()
     return pycompat.ossep.join((['..'] * len(a)) + b) or '.'
 
 def mainfrozen():
     """return True if we are a frozen executable.
 
     The code supports py2exe (most common, Windows only) and tools/freeze
     (portable, not much used).
     """
     return (safehasattr(sys, "frozen") or # new py2exe
             safehasattr(sys, "importers") or # old py2exe
             imp.is_frozen(u"__main__")) # tools/freeze
 
 # the location of data files matching the source code
 if mainfrozen() and getattr(sys, 'frozen', None) != 'macosx_app':
     # executable version (py2exe) doesn't support __file__
-    datapath = os.path.dirname(sys.executable)
+    datapath = os.path.dirname(pycompat.sysexecutable)
 else:
     datapath = os.path.dirname(__file__)
 
 if not isinstance(datapath, bytes):
     datapath = pycompat.fsencode(datapath)
 
 i18n.setdatapath(datapath)
 
 _hgexecutable = None
 
 def hgexecutable():
     """return location of the 'hg' executable.
 
     Defaults to $HG or 'hg' in the search path.
     """
     if _hgexecutable is None:
         hg = encoding.environ.get('HG')
         mainmod = sys.modules['__main__']
         if hg:
             _sethgexecutable(hg)
         elif mainfrozen():
             if getattr(sys, 'frozen', None) == 'macosx_app':
                 # Env variable set by py2app
                 _sethgexecutable(encoding.environ['EXECUTABLEPATH'])
             else:
-                _sethgexecutable(sys.executable)
+                _sethgexecutable(pycompat.sysexecutable)
         elif os.path.basename(getattr(mainmod, '__file__', '')) == 'hg':
             _sethgexecutable(mainmod.__file__)
         else:
             exe = findexe('hg') or os.path.basename(sys.argv[0])
             _sethgexecutable(exe)
     return _hgexecutable
 
 def _sethgexecutable(path):
     """set location of the 'hg' executable"""
     global _hgexecutable
     _hgexecutable = path
 
 def _isstdout(f):
     fileno = getattr(f, 'fileno', None)
     return fileno and fileno() == sys.__stdout__.fileno()
 
 def system(cmd, environ=None, cwd=None, onerr=None, errprefix=None, out=None):
     '''enhanced shell command execution.
     run with environment maybe modified, maybe in different dir.
 
     if command fails and onerr is None, return status, else raise onerr
     object as exception.
 
     if out is specified, it is assumed to be a file-like object that has a
     write() method. stdout and stderr will be redirected to out.'''
     if environ is None:
         environ = {}
     try:
         stdout.flush()
     except Exception:
         pass
     def py2shell(val):
         'convert python object into string that is useful to shell'
         if val is None or val is False:
             return '0'
         if val is True:
             return '1'
         return str(val)
     origcmd = cmd
     cmd = quotecommand(cmd)
     if pycompat.sysplatform == 'plan9' and (sys.version_info[0] == 2
                                     and sys.version_info[1] < 7):
         # subprocess kludge to work around issues in half-baked Python
         # ports, notably bichued/python:
         if not cwd is None:
             os.chdir(cwd)
         rc = os.system(cmd)
     else:
         env = dict(encoding.environ)
         env.update((k, py2shell(v)) for k, v in environ.iteritems())
         env['HG'] = hgexecutable()
         if out is None or _isstdout(out):
             rc = subprocess.call(cmd, shell=True, close_fds=closefds,
                                  env=env, cwd=cwd)
         else:
             proc = subprocess.Popen(cmd, shell=True, close_fds=closefds,
                                     env=env, cwd=cwd, stdout=subprocess.PIPE,
                                     stderr=subprocess.STDOUT)
             for line in iter(proc.stdout.readline, ''):
                 out.write(line)
             proc.wait()
             rc = proc.returncode
         if pycompat.sysplatform == 'OpenVMS' and rc & 1:
             rc = 0
     if rc and onerr:
         errmsg = '%s %s' % (os.path.basename(origcmd.split(None, 1)[0]),
                             explainexit(rc)[0])
         if errprefix:
             errmsg = '%s: %s' % (errprefix, errmsg)
         raise onerr(errmsg)
     return rc
 
 def checksignature(func):
     '''wrap a function with code to check for calling errors'''
     def check(*args, **kwargs):
         try:
             return func(*args, **kwargs)
         except TypeError:
             if len(traceback.extract_tb(sys.exc_info()[2])) == 1:
                 raise error.SignatureError
             raise
 
     return check
 
 def copyfile(src, dest, hardlink=False, copystat=False, checkambig=False):
     '''copy a file, preserving mode and optionally other stat info like
     atime/mtime
 
     checkambig argument is used with filestat, and is useful only if
     destination file is guarded by any lock (e.g. repo.lock or
     repo.wlock).
 
     copystat and checkambig should be exclusive.
     '''
     assert not (copystat and checkambig)
     oldstat = None
     if os.path.lexists(dest):
         if checkambig:
             oldstat = checkambig and filestat(dest)
         unlink(dest)
     # hardlinks are problematic on CIFS, quietly ignore this flag
     # until we find a way to work around it cleanly (issue4546)
     if False and hardlink:
         try:
             oslink(src, dest)
             return
         except (IOError, OSError):
             pass # fall back to normal copy
     if os.path.islink(src):
         os.symlink(os.readlink(src), dest)
         # copytime is ignored for symlinks, but in general copytime isn't needed
         # for them anyway
     else:
         try:
             shutil.copyfile(src, dest)
             if copystat:
                 # copystat also copies mode
                 shutil.copystat(src, dest)
             else:
                 shutil.copymode(src, dest)
                 if oldstat and oldstat.stat:
                     newstat = filestat(dest)
                     if newstat.isambig(oldstat):
                         # stat of copied file is ambiguous to original one
                         advanced = (oldstat.stat.st_mtime + 1) & 0x7fffffff
                         os.utime(dest, (advanced, advanced))
         except shutil.Error as inst:
             raise Abort(str(inst))
 
 def copyfiles(src, dst, hardlink=None, progress=lambda t, pos: None):
     """Copy a directory tree using hardlinks if possible."""
     num = 0
 
     if hardlink is None:
         hardlink = (os.stat(src).st_dev ==
                     os.stat(os.path.dirname(dst)).st_dev)
     if hardlink:
         topic = _('linking')
     else:
         topic = _('copying')
 
     if os.path.isdir(src):
         os.mkdir(dst)
         for name, kind in osutil.listdir(src):
             srcname = os.path.join(src, name)
             dstname = os.path.join(dst, name)
             def nprog(t, pos):
                 if pos is not None:
                     return progress(t, pos + num)
             hardlink, n = copyfiles(srcname, dstname, hardlink, progress=nprog)
             num += n
     else:
         if hardlink:
             try:
                 oslink(src, dst)
             except (IOError, OSError):
                 hardlink = False
                 shutil.copy(src, dst)
         else:
             shutil.copy(src, dst)
         num += 1
         progress(topic, num)
     progress(topic, None)
 
     return hardlink, num
 
 _winreservednames = '''con prn aux nul
     com1 com2 com3 com4 com5 com6 com7 com8 com9
     lpt1 lpt2 lpt3 lpt4 lpt5 lpt6 lpt7 lpt8 lpt9'''.split()
 _winreservedchars = ':*?"<>|'
 def checkwinfilename(path):
     r'''Check that the base-relative path is a valid filename on Windows.
     Returns None if the path is ok, or a UI string describing the problem.
 
     >>> checkwinfilename("just/a/normal/path")
     >>> checkwinfilename("foo/bar/con.xml")
     "filename contains 'con', which is reserved on Windows"
     >>> checkwinfilename("foo/con.xml/bar")
     "filename contains 'con', which is reserved on Windows"
     >>> checkwinfilename("foo/bar/xml.con")
     >>> checkwinfilename("foo/bar/AUX/bla.txt")
     "filename contains 'AUX', which is reserved on Windows"
     >>> checkwinfilename("foo/bar/bla:.txt")
     "filename contains ':', which is reserved on Windows"
     >>> checkwinfilename("foo/bar/b\07la.txt")
     "filename contains '\\x07', which is invalid on Windows"
     >>> checkwinfilename("foo/bar/bla ")
     "filename ends with ' ', which is not allowed on Windows"
     >>> checkwinfilename("../bar")
     >>> checkwinfilename("foo\\")
     "filename ends with '\\', which is invalid on Windows"
     >>> checkwinfilename("foo\\/bar")
     "directory name ends with '\\', which is invalid on Windows"
     '''
     if path.endswith('\\'):
         return _("filename ends with '\\', which is invalid on Windows")
     if '\\/' in path:
         return _("directory name ends with '\\', which is invalid on Windows")
     for n in path.replace('\\', '/').split('/'):
         if not n:
             continue
         for c in n:
             if c in _winreservedchars:
                 return _("filename contains '%s', which is reserved "
                          "on Windows") % c
             if ord(c) <= 31:
                 return _("filename contains %r, which is invalid "
                          "on Windows") % c
         base = n.split('.')[0]
         if base and base.lower() in _winreservednames:
             return _("filename contains '%s', which is reserved "
                      "on Windows") % base
         t = n[-1]
         if t in '. ' and n not in '..':
             return _("filename ends with '%s', which is not allowed "
                      "on Windows") % t
 
 if pycompat.osname == 'nt':
     checkosfilename = checkwinfilename
 else:
     checkosfilename = platform.checkosfilename
 
 def makelock(info, pathname):
     try:
         return os.symlink(info, pathname)
     except OSError as why:
         if why.errno == errno.EEXIST:
             raise
     except AttributeError: # no symlink in os
         pass
 
     ld = os.open(pathname, os.O_CREAT | os.O_WRONLY | os.O_EXCL)
     os.write(ld, info)
     os.close(ld)
 
 def readlock(pathname):
     try:
         return os.readlink(pathname)
     except OSError as why:
         if why.errno not in (errno.EINVAL, errno.ENOSYS):
             raise
     except AttributeError: # no symlink in os
         pass
     fp = posixfile(pathname)
     r = fp.read()
     fp.close()
     return r
 
 def fstat(fp):
     '''stat file object that may not have fileno method.'''
     try:
         return os.fstat(fp.fileno())
     except AttributeError:
         return os.stat(fp.name)
 
 # File system features
 
 def fscasesensitive(path):
     """
     Return true if the given path is on a case-sensitive filesystem
 
     Requires a path (like /foo/.hg) ending with a foldable final
     directory component.
     """
     s1 = os.lstat(path)
     d, b = os.path.split(path)
     b2 = b.upper()
     if b == b2:
         b2 = b.lower()
         if b == b2:
             return True # no evidence against case sensitivity
     p2 = os.path.join(d, b2)
     try:
         s2 = os.lstat(p2)
         if s2 == s1:
             return False
         return True
     except OSError:
         return True
 
 try:
     import re2
     _re2 = None
 except ImportError:
     _re2 = False
 
 class _re(object):
     def _checkre2(self):
         global _re2
         try:
             # check if match works, see issue3964
             _re2 = bool(re2.match(r'\[([^\[]+)\]', '[ui]'))
         except ImportError:
             _re2 = False
 
     def compile(self, pat, flags=0):
         '''Compile a regular expression, using re2 if possible
 
         For best performance, use only re2-compatible regexp features. The
         only flags from the re module that are re2-compatible are
         IGNORECASE and MULTILINE.'''
         if _re2 is None:
             self._checkre2()
         if _re2 and (flags & ~(remod.IGNORECASE | remod.MULTILINE)) == 0:
             if flags & remod.IGNORECASE:
                 pat = '(?i)' + pat
             if flags & remod.MULTILINE:
                 pat = '(?m)' + pat
             try:
                 return re2.compile(pat)
             except re2.error:
                 pass
         return remod.compile(pat, flags)
 
     @propertycache
     def escape(self):
         '''Return the version of escape corresponding to self.compile.
 
         This is imperfect because whether re2 or re is used for a particular
         function depends on the flags, etc, but it's the best we can do.
         '''
         global _re2
         if _re2 is None:
             self._checkre2()
         if _re2:
             return re2.escape
         else:
             return remod.escape
 
 re = _re()
 
 _fspathcache = {}
 def fspath(name, root):
     '''Get name in the case stored in the filesystem
 
     The name should be relative to root, and be normcase-ed for efficiency.
 
     Note that this function is unnecessary, and should not be
     called, for case-sensitive filesystems (simply because it's expensive).
 
     The root should be normcase-ed, too.
     '''
     def _makefspathcacheentry(dir):
         return dict((normcase(n), n) for n in os.listdir(dir))
 
     seps = pycompat.ossep
     if pycompat.osaltsep:
         seps = seps + pycompat.osaltsep
     # Protect backslashes. This gets silly very quickly.
     seps.replace('\\','\\\\')
     pattern = remod.compile(r'([^%s]+)|([%s]+)' % (seps, seps))
     dir = os.path.normpath(root)
     result = []
     for part, sep in pattern.findall(name):
         if sep:
             result.append(sep)
             continue
 
         if dir not in _fspathcache:
             _fspathcache[dir] = _makefspathcacheentry(dir)
         contents = _fspathcache[dir]
 
         found = contents.get(part)
         if not found:
             # retry "once per directory" per "dirstate.walk" which
             # may take place for each patches of "hg qpush", for example
             _fspathcache[dir] = contents = _makefspathcacheentry(dir)
             found = contents.get(part)
 
         result.append(found or part)
         dir = os.path.join(dir, part)
 
     return ''.join(result)
 
 def checknlink(testfile):
     '''check whether hardlink count reporting works properly'''
 
     # testfile may be open, so we need a separate file for checking to
     # work around issue2543 (or testfile may get lost on Samba shares)
     f1 = testfile + ".hgtmp1"
     if os.path.lexists(f1):
         return False
     try:
         posixfile(f1, 'w').close()
     except IOError:
         try:
             os.unlink(f1)
         except OSError:
             pass
         return False
 
     f2 = testfile + ".hgtmp2"
     fd = None
     try:
         oslink(f1, f2)
         # nlinks() may behave differently for files on Windows shares if
         # the file is open.
         fd = posixfile(f2)
         return nlinks(f2) > 1
     except OSError:
         return False
     finally:
         if fd is not None:
             fd.close()
         for f in (f1, f2):
             try:
                 os.unlink(f)
             except OSError:
                 pass
 
 def endswithsep(path):
     '''Check path ends with os.sep or os.altsep.'''
     return (path.endswith(pycompat.ossep)
             or pycompat.osaltsep and path.endswith(pycompat.osaltsep))
 
 def splitpath(path):
     '''Split path by os.sep.
     Note that this function does not use os.altsep because this is
     an alternative of simple "xxx.split(os.sep)".
     It is recommended to use os.path.normpath() before using this
     function if need.'''
     return path.split(pycompat.ossep)
 
 def gui():
     '''Are we running in a GUI?'''
     if pycompat.sysplatform == 'darwin':
         if 'SSH_CONNECTION' in encoding.environ:
             # handle SSH access to a box where the user is logged in
             return False
         elif getattr(osutil, 'isgui', None):
             # check if a CoreGraphics session is available
             return osutil.isgui()
         else:
             # pure build; use a safe default
             return True
     else:
         return pycompat.osname == "nt" or encoding.environ.get("DISPLAY")
 
 def mktempcopy(name, emptyok=False, createmode=None):
     """Create a temporary file with the same contents from name
 
     The permission bits are copied from the original file.
 
     If the temporary file is going to be truncated immediately, you
     can use emptyok=True as an optimization.
 
     Returns the name of the temporary file.
     """
     d, fn = os.path.split(name)
     fd, temp = tempfile.mkstemp(prefix='.%s-' % fn, dir=d)
     os.close(fd)
     # Temporary files are created with mode 0600, which is usually not
     # what we want.  If the original file already exists, just copy
     # its mode.  Otherwise, manually obey umask.
     copymode(name, temp, createmode)
     if emptyok:
         return temp
     try:
         try:
             ifp = posixfile(name, "rb")
         except IOError as inst:
             if inst.errno == errno.ENOENT:
                 return temp
             if not getattr(inst, 'filename', None):
                 inst.filename = name
             raise
         ofp = posixfile(temp, "wb")
         for chunk in filechunkiter(ifp):
             ofp.write(chunk)
         ifp.close()
         ofp.close()
     except: # re-raises
         try: os.unlink(temp)
         except OSError: pass
         raise
     return temp
 
 class filestat(object):
     """help to exactly detect change of a file
 
     'stat' attribute is result of 'os.stat()' if specified 'path'
     exists. Otherwise, it is None. This can avoid preparative
     'exists()' examination on client side of this class.
     """
     def __init__(self, path):
         try:
             self.stat = os.stat(path)
         except OSError as err:
             if err.errno != errno.ENOENT:
                 raise
             self.stat = None
 
     __hash__ = object.__hash__
 
     def __eq__(self, old):
         try:
             # if ambiguity between stat of new and old file is
             # avoided, comparison of size, ctime and mtime is enough
             # to exactly detect change of a file regardless of platform
             return (self.stat.st_size == old.stat.st_size and
                     self.stat.st_ctime == old.stat.st_ctime and
                     self.stat.st_mtime == old.stat.st_mtime)
         except AttributeError:
             return False
 
     def isambig(self, old):
         """Examine whether new (= self) stat is ambiguous against old one
 
         "S[N]" below means stat of a file at N-th change:
 
         - S[n-1].ctime  < S[n].ctime: can detect change of a file
         - S[n-1].ctime == S[n].ctime
           - S[n-1].ctime  < S[n].mtime: means natural advancing (*1)
           - S[n-1].ctime == S[n].mtime: is ambiguous (*2)
           - S[n-1].ctime  > S[n].mtime: never occurs naturally (don't care)
         - S[n-1].ctime  > S[n].ctime: never occurs naturally (don't care)
 
         Case (*2) above means that a file was changed twice or more at
         same time in sec (= S[n-1].ctime), and comparison of timestamp
         is ambiguous.
 
         Base idea to avoid such ambiguity is "advance mtime 1 sec, if
         timestamp is ambiguous".
 
         But advancing mtime only in case (*2) doesn't work as
         expected, because naturally advanced S[n].mtime in case (*1)
         might be equal to manually advanced S[n-1 or earlier].mtime.
 
         Therefore, all "S[n-1].ctime == S[n].ctime" cases should be
         treated as ambiguous regardless of mtime, to avoid overlooking
         by confliction between such mtime.
 
         Advancing mtime "if isambig(oldstat)" ensures "S[n-1].mtime !=
         S[n].mtime", even if size of a file isn't changed.
         """
         try:
             return (self.stat.st_ctime == old.stat.st_ctime)
         except AttributeError:
             return False
 
     def avoidambig(self, path, old):
         """Change file stat of specified path to avoid ambiguity
 
         'old' should be previous filestat of 'path'.
 
         This skips avoiding ambiguity, if a process doesn't have
         appropriate privileges for 'path'.
         """
         advanced = (old.stat.st_mtime + 1) & 0x7fffffff
         try:
             os.utime(path, (advanced, advanced))
         except OSError as inst:
             if inst.errno == errno.EPERM:
                 # utime() on the file created by another user causes EPERM,
                 # if a process doesn't have appropriate privileges
                 return
             raise
 
     def __ne__(self, other):
         return not self == other
 
 class atomictempfile(object):
     '''writable file object that atomically updates a file
 
     All writes will go to a temporary copy of the original file. Call
     close() when you are done writing, and atomictempfile will rename
     the temporary copy to the original name, making the changes
     visible. If the object is destroyed without being closed, all your
     writes are discarded.
 
     checkambig argument of constructor is used with filestat, and is
     useful only if target file is guarded by any lock (e.g. repo.lock
     or repo.wlock).
     '''
     def __init__(self, name, mode='w+b', createmode=None, checkambig=False):
         self.__name = name      # permanent name
         self._tempname = mktempcopy(name, emptyok=('w' in mode),
                                     createmode=createmode)
         self._fp = posixfile(self._tempname, mode)
         self._checkambig = checkambig
 
         # delegated methods
         self.read = self._fp.read
         self.write = self._fp.write
         self.seek = self._fp.seek
         self.tell = self._fp.tell
         self.fileno = self._fp.fileno
 
     def close(self):
         if not self._fp.closed:
             self._fp.close()
             filename = localpath(self.__name)
             oldstat = self._checkambig and filestat(filename)
             if oldstat and oldstat.stat:
                 rename(self._tempname, filename)
                 newstat = filestat(filename)
                 if newstat.isambig(oldstat):
                     # stat of changed file is ambiguous to original one
                     advanced = (oldstat.stat.st_mtime + 1) & 0x7fffffff
                     os.utime(filename, (advanced, advanced))
             else:
                 rename(self._tempname, filename)
 
     def discard(self):
         if not self._fp.closed:
             try:
                 os.unlink(self._tempname)
             except OSError:
                 pass
             self._fp.close()
 
     def __del__(self):
         if safehasattr(self, '_fp'): # constructor actually did something
             self.discard()
 
     def __enter__(self):
         return self
 
     def __exit__(self, exctype, excvalue, traceback):
         if exctype is not None:
             self.discard()
         else:
             self.close()
 
 def makedirs(name, mode=None, notindexed=False):
     """recursive directory creation with parent mode inheritance
 
     Newly created directories are marked as "not to be indexed by
     the content indexing service", if ``notindexed`` is specified
     for "write" mode access.
     """
     try:
         makedir(name, notindexed)
     except OSError as err:
         if err.errno == errno.EEXIST:
             return
         if err.errno != errno.ENOENT or not name:
             raise
         parent = os.path.dirname(os.path.abspath(name))
         if parent == name:
             raise
         makedirs(parent, mode, notindexed)
         try:
             makedir(name, notindexed)
         except OSError as err:
             # Catch EEXIST to handle races
             if err.errno == errno.EEXIST:
                 return
             raise
     if mode is not None:
         os.chmod(name, mode)
 
 def readfile(path):
     with open(path, 'rb') as fp:
         return fp.read()
 
 def writefile(path, text):
     with open(path, 'wb') as fp:
         fp.write(text)
 
 def appendfile(path, text):
     with open(path, 'ab') as fp:
         fp.write(text)
 
 class chunkbuffer(object):
     """Allow arbitrary sized chunks of data to be efficiently read from an
     iterator over chunks of arbitrary size."""
 
     def __init__(self, in_iter):
         """in_iter is the iterator that's iterating over the input chunks.
         targetsize is how big a buffer to try to maintain."""
         def splitbig(chunks):
             for chunk in chunks:
                 if len(chunk) > 2**20:
                     pos = 0
                     while pos < len(chunk):
                         end = pos + 2 ** 18
                         yield chunk[pos:end]
                         pos = end
                 else:
                     yield chunk
         self.iter = splitbig(in_iter)
         self._queue = collections.deque()
         self._chunkoffset = 0
 
     def read(self, l=None):
         """Read L bytes of data from the iterator of chunks of data.
         Returns less than L bytes if the iterator runs dry.
 
         If size parameter is omitted, read everything"""
         if l is None:
             return ''.join(self.iter)
 
         left = l
         buf = []
         queue = self._queue
         while left > 0:
             # refill the queue
             if not queue:
                 target = 2**18
                 for chunk in self.iter:
                     queue.append(chunk)
                     target -= len(chunk)
                     if target <= 0:
                         break
                 if not queue:
                     break
 
             # The easy way to do this would be to queue.popleft(), modify the
             # chunk (if necessary), then queue.appendleft(). However, for cases
             # where we read partial chunk content, this incurs 2 dequeue
             # mutations and creates a new str for the remaining chunk in the
             # queue. Our code below avoids this overhead.
 
             chunk = queue[0]
             chunkl = len(chunk)
             offset = self._chunkoffset
 
             # Use full chunk.
             if offset == 0 and left >= chunkl:
                 left -= chunkl
                 queue.popleft()
                 buf.append(chunk)
                 # self._chunkoffset remains at 0.
                 continue
 
             chunkremaining = chunkl - offset
 
             # Use all of unconsumed part of chunk.
             if left >= chunkremaining:
                 left -= chunkremaining
                 queue.popleft()
                 # offset == 0 is enabled by block above, so this won't merely
                 # copy via ``chunk[0:]``.
                 buf.append(chunk[offset:])
                 self._chunkoffset = 0
 
             # Partial chunk needed.
             else:
                 buf.append(chunk[offset:offset + left])
                 self._chunkoffset += left
                 left -= chunkremaining
 
         return ''.join(buf)
 
 def filechunkiter(f, size=131072, limit=None):
     """Create a generator that produces the data in the file size
     (default 131072) bytes at a time, up to optional limit (default is
     to read all data).  Chunks may be less than size bytes if the
     chunk is the last chunk in the file, or the file is a socket or
     some other type of file that sometimes reads less data than is
     requested."""
     assert size >= 0
     assert limit is None or limit >= 0
     while True:
         if limit is None:
             nbytes = size
         else:
             nbytes = min(limit, size)
         s = nbytes and f.read(nbytes)
         if not s:
             break
         if limit:
             limit -= len(s)
         yield s
 
 def makedate(timestamp=None):
     '''Return a unix timestamp (or the current time) as a (unixtime,
     offset) tuple based off the local timezone.'''
     if timestamp is None:
         timestamp = time.time()
     if timestamp < 0:
         hint = _("check your clock")
         raise Abort(_("negative timestamp: %d") % timestamp, hint=hint)
     delta = (datetime.datetime.utcfromtimestamp(timestamp) -
              datetime.datetime.fromtimestamp(timestamp))
     tz = delta.days * 86400 + delta.seconds
     return timestamp, tz
 
 def datestr(date=None, format='%a %b %d %H:%M:%S %Y %1%2'):
     """represent a (unixtime, offset) tuple as a localized time.
     unixtime is seconds since the epoch, and offset is the time zone's
     number of seconds away from UTC.
 
     >>> datestr((0, 0))
     'Thu Jan 01 00:00:00 1970 +0000'
     >>> datestr((42, 0))
     'Thu Jan 01 00:00:42 1970 +0000'
     >>> datestr((-42, 0))
     'Wed Dec 31 23:59:18 1969 +0000'
     >>> datestr((0x7fffffff, 0))
     'Tue Jan 19 03:14:07 2038 +0000'
     >>> datestr((-0x80000000, 0))
     'Fri Dec 13 20:45:52 1901 +0000'
     """
     t, tz = date or makedate()
     if "%1" in format or "%2" in format or "%z" in format:
         sign = (tz > 0) and "-" or "+"
         minutes = abs(tz) // 60
         q, r = divmod(minutes, 60)
         format = format.replace("%z", "%1%2")
         format = format.replace("%1", "%c%02d" % (sign, q))
         format = format.replace("%2", "%02d" % r)
     d = t - tz
     if d > 0x7fffffff:
         d = 0x7fffffff
     elif d < -0x80000000:
         d = -0x80000000
     # Never use time.gmtime() and datetime.datetime.fromtimestamp()
     # because they use the gmtime() system call which is buggy on Windows
     # for negative values.
     t = datetime.datetime(1970, 1, 1) + datetime.timedelta(seconds=d)
     s = t.strftime(format)
     return s
 
 def shortdate(date=None):
     """turn (timestamp, tzoff) tuple into iso 8631 date."""
     return datestr(date, format='%Y-%m-%d')
 
 def parsetimezone(s):
     """find a trailing timezone, if any, in string, and return a
        (offset, remainder) pair"""
 
     if s.endswith("GMT") or s.endswith("UTC"):
         return 0, s[:-3].rstrip()
 
     # Unix-style timezones [+-]hhmm
     if len(s) >= 5 and s[-5] in "+-" and s[-4:].isdigit():
         sign = (s[-5] == "+") and 1 or -1
         hours = int(s[-4:-2])
         minutes = int(s[-2:])
         return -sign * (hours * 60 + minutes) * 60, s[:-5].rstrip()
 
     # ISO8601 trailing Z
     if s.endswith("Z") and s[-2:-1].isdigit():
         return 0, s[:-1]
 
     # ISO8601-style [+-]hh:mm
     if (len(s) >= 6 and s[-6] in "+-" and s[-3] == ":" and
         s[-5:-3].isdigit() and s[-2:].isdigit()):
         sign = (s[-6] == "+") and 1 or -1
         hours = int(s[-5:-3])
         minutes = int(s[-2:])
         return -sign * (hours * 60 + minutes) * 60, s[:-6]
 
     return None, s
 
 def strdate(string, format, defaults=[]):
     """parse a localized time string and return a (unixtime, offset) tuple.
     if the string cannot be parsed, ValueError is raised."""
     # NOTE: unixtime = localunixtime + offset
     offset, date = parsetimezone(string)
 
     # add missing elements from defaults
     usenow = False # default to using biased defaults
     for part in ("S", "M", "HI", "d", "mb", "yY"): # decreasing specificity
         found = [True for p in part if ("%"+p) in format]
         if not found:
             date += "@" + defaults[part][usenow]
             format += "@%" + part[0]
         else:
             # We've found a specific time element, less specific time
             # elements are relative to today
             usenow = True
 
     timetuple = time.strptime(date, format)
     localunixtime = int(calendar.timegm(timetuple))
     if offset is None:
         # local timezone
         unixtime = int(time.mktime(timetuple))
         offset = unixtime - localunixtime
     else:
         unixtime = localunixtime + offset
     return unixtime, offset
 
 def parsedate(date, formats=None, bias=None):
     """parse a localized date/time and return a (unixtime, offset) tuple.
 
     The date may be a "unixtime offset" string or in one of the specified
     formats. If the date already is a (unixtime, offset) tuple, it is returned.
 
     >>> parsedate(' today ') == parsedate(\
                                   datetime.date.today().strftime('%b %d'))
     True
     >>> parsedate( 'yesterday ') == parsedate((datetime.date.today() -\
                                                datetime.timedelta(days=1)\
                                               ).strftime('%b %d'))
     True
     >>> now, tz = makedate()
     >>> strnow, strtz = parsedate('now')
     >>> (strnow - now) < 1
     True
     >>> tz == strtz
     True
     """
     if bias is None:
         bias = {}
     if not date:
         return 0, 0
     if isinstance(date, tuple) and len(date) == 2:
         return date
     if not formats:
         formats = defaultdateformats
     date = date.strip()
 
     if date == 'now' or date == _('now'):
         return makedate()
     if date == 'today' or date == _('today'):
         date = datetime.date.today().strftime('%b %d')
     elif date == 'yesterday' or date == _('yesterday'):
         date = (datetime.date.today() -
                 datetime.timedelta(days=1)).strftime('%b %d')
 
     try:
         when, offset = map(int, date.split(' '))
     except ValueError:
         # fill out defaults
         now = makedate()
         defaults = {}
         for part in ("d", "mb", "yY", "HI", "M", "S"):
             # this piece is for rounding the specific end of unknowns
             b = bias.get(part)
             if b is None:
                 if part[0] in "HMS":
                     b = "00"
                 else:
                     b = "0"
 
             # this piece is for matching the generic end to today's date
             n = datestr(now, "%" + part[0])
 
             defaults[part] = (b, n)
 
         for format in formats:
             try:
                 when, offset = strdate(date, format, defaults)
             except (ValueError, OverflowError):
                 pass
             else:
                 break
         else:
             raise Abort(_('invalid date: %r') % date)
     # validate explicit (probably user-specified) date and
     # time zone offset. values must fit in signed 32 bits for
     # current 32-bit linux runtimes. timezones go from UTC-12
     # to UTC+14
     if when < -0x80000000 or when > 0x7fffffff:
         raise Abort(_('date exceeds 32 bits: %d') % when)
     if offset < -50400 or offset > 43200:
         raise Abort(_('impossible time zone offset: %d') % offset)
     return when, offset
 
 def matchdate(date):
     """Return a function that matches a given date match specifier
 
     Formats include:
 
     '{date}' match a given date to the accuracy provided
 
     '<{date}' on or before a given date
 
     '>{date}' on or after a given date
 
     >>> p1 = parsedate("10:29:59")
     >>> p2 = parsedate("10:30:00")
     >>> p3 = parsedate("10:30:59")
     >>> p4 = parsedate("10:31:00")
     >>> p5 = parsedate("Sep 15 10:30:00 1999")
     >>> f = matchdate("10:30")
     >>> f(p1[0])
     False
     >>> f(p2[0])
     True
     >>> f(p3[0])
     True
     >>> f(p4[0])
     False
     >>> f(p5[0])
     False
     """
 
     def lower(date):
         d = {'mb': "1", 'd': "1"}
         return parsedate(date, extendeddateformats, d)[0]
 
     def upper(date):
         d = {'mb': "12", 'HI': "23", 'M': "59", 'S': "59"}
         for days in ("31", "30", "29"):
             try:
                 d["d"] = days
                 return parsedate(date, extendeddateformats, d)[0]
             except Abort:
                 pass
         d["d"] = "28"
         return parsedate(date, extendeddateformats, d)[0]
 
     date = date.strip()
 
     if not date:
         raise Abort(_("dates cannot consist entirely of whitespace"))
     elif date[0] == "<":
         if not date[1:]:
             raise Abort(_("invalid day spec, use '<DATE'"))
         when = upper(date[1:])
         return lambda x: x <= when
     elif date[0] == ">":
         if not date[1:]:
             raise Abort(_("invalid day spec, use '>DATE'"))
         when = lower(date[1:])
         return lambda x: x >= when
     elif date[0] == "-":
         try:
             days = int(date[1:])
         except ValueError:
             raise Abort(_("invalid day spec: %s") % date[1:])
         if days < 0:
             raise Abort(_("%s must be nonnegative (see 'hg help dates')")
                 % date[1:])
         when = makedate()[0] - days * 3600 * 24
         return lambda x: x >= when
     elif " to " in date:
         a, b = date.split(" to ")
         start, stop = lower(a), upper(b)
         return lambda x: x >= start and x <= stop
     else:
         start, stop = lower(date), upper(date)
         return lambda x: x >= start and x <= stop
 
 def stringmatcher(pattern):
     """
     accepts a string, possibly starting with 're:' or 'literal:' prefix.
     returns the matcher name, pattern, and matcher function.
     missing or unknown prefixes are treated as literal matches.
 
     helper for tests:
     >>> def test(pattern, *tests):
     ...     kind, pattern, matcher = stringmatcher(pattern)
     ...     return (kind, pattern, [bool(matcher(t)) for t in tests])
 
     exact matching (no prefix):
     >>> test('abcdefg', 'abc', 'def', 'abcdefg')
     ('literal', 'abcdefg', [False, False, True])
 
     regex matching ('re:' prefix)
     >>> test('re:a.+b', 'nomatch', 'fooadef', 'fooadefbar')
     ('re', 'a.+b', [False, False, True])
 
     force exact matches ('literal:' prefix)
     >>> test('literal:re:foobar', 'foobar', 're:foobar')
     ('literal', 're:foobar', [False, True])
 
     unknown prefixes are ignored and treated as literals
     >>> test('foo:bar', 'foo', 'bar', 'foo:bar')
     ('literal', 'foo:bar', [False, False, True])
     """
     if pattern.startswith('re:'):
         pattern = pattern[3:]
         try:
             regex = remod.compile(pattern)
         except remod.error as e:
             raise error.ParseError(_('invalid regular expression: %s')
                                    % e)
         return 're', pattern, regex.search
     elif pattern.startswith('literal:'):
         pattern = pattern[8:]
     return 'literal', pattern, pattern.__eq__
 
 def shortuser(user):
     """Return a short representation of a user name or email address."""
     f = user.find('@')
     if f >= 0:
         user = user[:f]
     f = user.find('<')
     if f >= 0:
         user = user[f + 1:]
     f = user.find(' ')
     if f >= 0:
         user = user[:f]
     f = user.find('.')
     if f >= 0:
         user = user[:f]
     return user
 
 def emailuser(user):
     """Return the user portion of an email address."""
     f = user.find('@')
     if f >= 0:
         user = user[:f]
     f = user.find('<')
     if f >= 0:
         user = user[f + 1:]
     return user
 
 def email(author):
     '''get email of author.'''
     r = author.find('>')
     if r == -1:
         r = None
     return author[author.find('<') + 1:r]
 
 def ellipsis(text, maxlength=400):
     """Trim string to at most maxlength (default: 400) columns in display."""
     return encoding.trim(text, maxlength, ellipsis='...')
 
 def unitcountfn(*unittable):
     '''return a function that renders a readable count of some quantity'''
 
     def go(count):
         for multiplier, divisor, format in unittable:
             if count >= divisor * multiplier:
                 return format % (count / float(divisor))
         return unittable[-1][2] % count
 
     return go
 
 bytecount = unitcountfn(
     (100, 1 << 30, _('%.0f GB')),
     (10, 1 << 30, _('%.1f GB')),
     (1, 1 << 30, _('%.2f GB')),
     (100, 1 << 20, _('%.0f MB')),
     (10, 1 << 20, _('%.1f MB')),
     (1, 1 << 20, _('%.2f MB')),
     (100, 1 << 10, _('%.0f KB')),
     (10, 1 << 10, _('%.1f KB')),
     (1, 1 << 10, _('%.2f KB')),
     (1, 1, _('%.0f bytes')),
     )
 
 def uirepr(s):
     # Avoid double backslash in Windows path repr()
     return repr(s).replace('\\\\', '\\')
 
 # delay import of textwrap
 def MBTextWrapper(**kwargs):
     class tw(textwrap.TextWrapper):
         """
         Extend TextWrapper for width-awareness.
 
         Neither number of 'bytes' in any encoding nor 'characters' is
         appropriate to calculate terminal columns for specified string.
 
         Original TextWrapper implementation uses built-in 'len()' directly,
         so overriding is needed to use width information of each characters.
 
         In addition, characters classified into 'ambiguous' width are
         treated as wide in East Asian area, but as narrow in other.
 
         This requires use decision to determine width of such characters.
         """
         def _cutdown(self, ucstr, space_left):
             l = 0
             colwidth = encoding.ucolwidth
             for i in xrange(len(ucstr)):
                 l += colwidth(ucstr[i])
                 if space_left < l:
                     return (ucstr[:i], ucstr[i:])
             return ucstr, ''
 
         # overriding of base class
         def _handle_long_word(self, reversed_chunks, cur_line, cur_len, width):
             space_left = max(width - cur_len, 1)
 
             if self.break_long_words:
                 cut, res = self._cutdown(reversed_chunks[-1], space_left)
                 cur_line.append(cut)
                 reversed_chunks[-1] = res
             elif not cur_line:
                 cur_line.append(reversed_chunks.pop())
 
         # this overriding code is imported from TextWrapper of Python 2.6
         # to calculate columns of string by 'encoding.ucolwidth()'
         def _wrap_chunks(self, chunks):
             colwidth = encoding.ucolwidth
 
             lines = []
             if self.width <= 0:
                 raise ValueError("invalid width %r (must be > 0)" % self.width)
 
             # Arrange in reverse order so items can be efficiently popped
             # from a stack of chucks.
             chunks.reverse()
 
             while chunks:
 
                 # Start the list of chunks that will make up the current line.
                 # cur_len is just the length of all the chunks in cur_line.
                 cur_line = []
                 cur_len = 0
 
                 # Figure out which static string will prefix this line.
                 if lines:
                     indent = self.subsequent_indent
                 else:
                     indent = self.initial_indent
 
                 # Maximum width for this line.
                 width = self.width - len(indent)
 
                 # First chunk on line is whitespace -- drop it, unless this
                 # is the very beginning of the text (i.e. no lines started yet).
                 if self.drop_whitespace and chunks[-1].strip() == '' and lines:
                     del chunks[-1]
 
                 while chunks:
                     l = colwidth(chunks[-1])
 
                     # Can at least squeeze this chunk onto the current line.
                     if cur_len + l <= width:
                         cur_line.append(chunks.pop())
                         cur_len += l
 
                     # Nope, this line is full.
                     else:
                         break
 
                 # The current line is full, and the next chunk is too big to
                 # fit on *any* line (not just this one).
                 if chunks and colwidth(chunks[-1]) > width:
                     self._handle_long_word(chunks, cur_line, cur_len, width)
 
                 # If the last chunk on this line is all whitespace, drop it.
                 if (self.drop_whitespace and
                     cur_line and cur_line[-1].strip() == ''):
                     del cur_line[-1]
 
                 # Convert current line back to a string and store it in list
                 # of all lines (return value).
                 if cur_line:
                     lines.append(indent + ''.join(cur_line))
 
             return lines
 
     global MBTextWrapper
     MBTextWrapper = tw
     return tw(**kwargs)
 
 def wrap(line, width, initindent='', hangindent=''):
     maxindent = max(len(hangindent), len(initindent))
     if width <= maxindent:
         # adjust for weird terminal size
         width = max(78, maxindent + 1)
     line = line.decode(encoding.encoding, encoding.encodingmode)
     initindent = initindent.decode(encoding.encoding, encoding.encodingmode)
     hangindent = hangindent.decode(encoding.encoding, encoding.encodingmode)
     wrapper = MBTextWrapper(width=width,
                             initial_indent=initindent,
                             subsequent_indent=hangindent)
     return wrapper.fill(line).encode(encoding.encoding)
 
 if (pyplatform.python_implementation() == 'CPython' and
     sys.version_info < (3, 0)):
     # There is an issue in CPython that some IO methods do not handle EINTR
     # correctly. The following table shows what CPython version (and functions)
     # are affected (buggy: has the EINTR bug, okay: otherwise):
     #
     #                | < 2.7.4 | 2.7.4 to 2.7.12 | >= 3.0
     #   --------------------------------------------------
     #    fp.__iter__ | buggy   | buggy           | okay
     #    fp.read*    | buggy   | okay [1]        | okay
     #
     # [1]: fixed by changeset 67dc99a989cd in the cpython hg repo.
     #
     # Here we workaround the EINTR issue for fileobj.__iter__. Other methods
     # like "read*" are ignored for now, as Python < 2.7.4 is a minority.
     #
     # Although we can workaround the EINTR issue for fp.__iter__, it is slower:
     # "for x in fp" is 4x faster than "for x in iter(fp.readline, '')" in
     # CPython 2, because CPython 2 maintains an internal readahead buffer for
     # fp.__iter__ but not other fp.read* methods.
     #
     # On modern systems like Linux, the "read" syscall cannot be interrupted
     # when reading "fast" files like on-disk files. So the EINTR issue only
     # affects things like pipes, sockets, ttys etc. We treat "normal" (S_ISREG)
     # files approximately as "fast" files and use the fast (unsafe) code path,
     # to minimize the performance impact.
     if sys.version_info >= (2, 7, 4):
         # fp.readline deals with EINTR correctly, use it as a workaround.
         def _safeiterfile(fp):
             return iter(fp.readline, '')
     else:
         # fp.read* are broken too, manually deal with EINTR in a stupid way.
         # note: this may block longer than necessary because of bufsize.
         def _safeiterfile(fp, bufsize=4096):
             fd = fp.fileno()
             line = ''
             while True:
                 try:
                     buf = os.read(fd, bufsize)
                 except OSError as ex:
                     # os.read only raises EINTR before any data is read
                     if ex.errno == errno.EINTR:
                         continue
                     else:
                         raise
                 line += buf
                 if '\n' in buf:
                     splitted = line.splitlines(True)
                     line = ''
                     for l in splitted:
                         if l[-1] == '\n':
                             yield l
                         else:
                             line = l
                 if not buf:
                     break
             if line:
                 yield line
 
     def iterfile(fp):
         fastpath = True
         if type(fp) is file:
             fastpath = stat.S_ISREG(os.fstat(fp.fileno()).st_mode)
         if fastpath:
             return fp
         else:
             return _safeiterfile(fp)
 else:
     # PyPy and CPython 3 do not have the EINTR issue thus no workaround needed.
     def iterfile(fp):
         return fp
 
 def iterlines(iterator):
     for chunk in iterator:
         for line in chunk.splitlines():
             yield line
 
 def expandpath(path):
     return os.path.expanduser(os.path.expandvars(path))
 
 def hgcmd():
     """Return the command used to execute current hg
 
     This is different from hgexecutable() because on Windows we want
     to avoid things opening new shell windows like batch files, so we
     get either the python call or current executable.
     """
     if mainfrozen():
         if getattr(sys, 'frozen', None) == 'macosx_app':
             # Env variable set by py2app
             return [encoding.environ['EXECUTABLEPATH']]
         else:
-            return [sys.executable]
+            return [pycompat.sysexecutable]
     return gethgcmd()
 
 def rundetached(args, condfn):
     """Execute the argument list in a detached process.
 
     condfn is a callable which is called repeatedly and should return
     True once the child process is known to have started successfully.
     At this point, the child process PID is returned. If the child
     process fails to start or finishes before condfn() evaluates to
     True, return -1.
     """
     # Windows case is easier because the child process is either
     # successfully starting and validating the condition or exiting
     # on failure. We just poll on its PID. On Unix, if the child
     # process fails to start, it will be left in a zombie state until
     # the parent wait on it, which we cannot do since we expect a long
     # running process on success. Instead we listen for SIGCHLD telling
     # us our child process terminated.
     terminated = set()
     def handler(signum, frame):
         terminated.add(os.wait())
     prevhandler = None
     SIGCHLD = getattr(signal, 'SIGCHLD', None)
     if SIGCHLD is not None:
         prevhandler = signal.signal(SIGCHLD, handler)
     try:
         pid = spawndetached(args)
         while not condfn():
             if ((pid in terminated or not testpid(pid))
                 and not condfn()):
                 return -1
             time.sleep(0.1)
         return pid
     finally:
         if prevhandler is not None:
             signal.signal(signal.SIGCHLD, prevhandler)
 
 def interpolate(prefix, mapping, s, fn=None, escape_prefix=False):
     """Return the result of interpolating items in the mapping into string s.
 
     prefix is a single character string, or a two character string with
     a backslash as the first character if the prefix needs to be escaped in
     a regular expression.
 
     fn is an optional function that will be applied to the replacement text
     just before replacement.
 
     escape_prefix is an optional flag that allows using doubled prefix for
     its escaping.
     """
     fn = fn or (lambda s: s)
     patterns = '|'.join(mapping.keys())
     if escape_prefix:
         patterns += '|' + prefix
         if len(prefix) > 1:
             prefix_char = prefix[1:]
         else:
             prefix_char = prefix
         mapping[prefix_char] = prefix_char
     r = remod.compile(r'%s(%s)' % (prefix, patterns))
     return r.sub(lambda x: fn(mapping[x.group()[1:]]), s)
 
 def getport(port):
     """Return the port for a given network service.
 
     If port is an integer, it's returned as is. If it's a string, it's
     looked up using socket.getservbyname(). If there's no matching
     service, error.Abort is raised.
     """
     try:
         return int(port)
     except ValueError:
         pass
 
     try:
         return socket.getservbyname(port)
     except socket.error:
         raise Abort(_("no port number associated with service '%s'") % port)
 
 _booleans = {'1': True, 'yes': True, 'true': True, 'on': True, 'always': True,
              '0': False, 'no': False, 'false': False, 'off': False,
              'never': False}
 
 def parsebool(s):
     """Parse s into a boolean.
 
     If s is not a valid boolean, returns None.
     """
     return _booleans.get(s.lower(), None)
 
 _hextochr = dict((a + b, chr(int(a + b, 16)))
                  for a in string.hexdigits for b in string.hexdigits)
 
 class url(object):
     r"""Reliable URL parser.
 
     This parses URLs and provides attributes for the following
     components:
 
     <scheme>://<user>:<passwd>@<host>:<port>/<path>?<query>#<fragment>
 
     Missing components are set to None. The only exception is
     fragment, which is set to '' if present but empty.
 
     If parsefragment is False, fragment is included in query. If
     parsequery is False, query is included in path. If both are
     False, both fragment and query are included in path.
 
     See http://www.ietf.org/rfc/rfc2396.txt for more information.
 
     Note that for backward compatibility reasons, bundle URLs do not
     take host names. That means 'bundle://../' has a path of '../'.
 
     Examples:
 
     >>> url('http://www.ietf.org/rfc/rfc2396.txt')
     <url scheme: 'http', host: 'www.ietf.org', path: 'rfc/rfc2396.txt'>
     >>> url('ssh://[::1]:2200//home/joe/repo')
     <url scheme: 'ssh', host: '[::1]', port: '2200', path: '/home/joe/repo'>
     >>> url('file:///home/joe/repo')
     <url scheme: 'file', path: '/home/joe/repo'>
     >>> url('file:///c:/temp/foo/')
     <url scheme: 'file', path: 'c:/temp/foo/'>
     >>> url('bundle:foo')
     <url scheme: 'bundle', path: 'foo'>
     >>> url('bundle://../foo')
     <url scheme: 'bundle', path: '../foo'>
     >>> url(r'c:\foo\bar')
     <url path: 'c:\\foo\\bar'>
     >>> url(r'\\blah\blah\blah')
     <url path: '\\\\blah\\blah\\blah'>
     >>> url(r'\\blah\blah\blah#baz')
     <url path: '\\\\blah\\blah\\blah', fragment: 'baz'>
     >>> url(r'file:///C:\users\me')
     <url scheme: 'file', path: 'C:\\users\\me'>
 
     Authentication credentials:
 
     >>> url('ssh://joe:xyz@x/repo')
     <url scheme: 'ssh', user: 'joe', passwd: 'xyz', host: 'x', path: 'repo'>
     >>> url('ssh://joe@x/repo')
     <url scheme: 'ssh', user: 'joe', host: 'x', path: 'repo'>
 
     Query strings and fragments:
 
     >>> url('http://host/a?b#c')
     <url scheme: 'http', host: 'host', path: 'a', query: 'b', fragment: 'c'>
     >>> url('http://host/a?b#c', parsequery=False, parsefragment=False)
     <url scheme: 'http', host: 'host', path: 'a?b#c'>
 
     Empty path:
 
     >>> url('')
     <url path: ''>
     >>> url('#a')
     <url path: '', fragment: 'a'>
     >>> url('http://host/')
     <url scheme: 'http', host: 'host', path: ''>
     >>> url('http://host/#a')
     <url scheme: 'http', host: 'host', path: '', fragment: 'a'>
 
     Only scheme:
 
     >>> url('http:')
     <url scheme: 'http'>
     """
 
     _safechars = "!~*'()+"
     _safepchars = "/!~*'()+:\\"
     _matchscheme = remod.compile('^[a-zA-Z0-9+.\\-]+:').match
 
     def __init__(self, path, parsequery=True, parsefragment=True):
         # We slowly chomp away at path until we have only the path left
         self.scheme = self.user = self.passwd = self.host = None
         self.port = self.path = self.query = self.fragment = None
         self._localpath = True
         self._hostport = ''
         self._origpath = path
 
         if parsefragment and '#' in path:
             path, self.fragment = path.split('#', 1)
 
         # special case for Windows drive letters and UNC paths
         if hasdriveletter(path) or path.startswith('\\\\'):
             self.path = path
             return
 
         # For compatibility reasons, we can't handle bundle paths as
         # normal URLS
         if path.startswith('bundle:'):
             self.scheme = 'bundle'
             path = path[7:]
             if path.startswith('//'):
                 path = path[2:]
             self.path = path
             return
 
         if self._matchscheme(path):
             parts = path.split(':', 1)
             if parts[0]:
                 self.scheme, path = parts
                 self._localpath = False
 
         if not path:
             path = None
             if self._localpath:
                 self.path = ''
                 return
         else:
             if self._localpath:
                 self.path = path
                 return
 
             if parsequery and '?' in path:
                 path, self.query = path.split('?', 1)
                 if not path:
                     path = None
                 if not self.query:
                     self.query = None
 
             # // is required to specify a host/authority
             if path and path.startswith('//'):
                 parts = path[2:].split('/', 1)
                 if len(parts) > 1:
                     self.host, path = parts
                 else:
                     self.host = parts[0]
                     path = None
                 if not self.host:
                     self.host = None
                     # path of file:///d is /d
                     # path of file:///d:/ is d:/, not /d:/
                     if path and not hasdriveletter(path):
                         path = '/' + path
 
             if self.host and '@' in self.host:
                 self.user, self.host = self.host.rsplit('@', 1)
                 if ':' in self.user:
                     self.user, self.passwd = self.user.split(':', 1)
                 if not self.host:
                     self.host = None
 
             # Don't split on colons in IPv6 addresses without ports
             if (self.host and ':' in self.host and
                 not (self.host.startswith('[') and self.host.endswith(']'))):
                 self._hostport = self.host
                 self.host, self.port = self.host.rsplit(':', 1)
                 if not self.host:
                     self.host = None
 
             if (self.host and self.scheme == 'file' and
                 self.host not in ('localhost', '127.0.0.1', '[::1]')):
                 raise Abort(_('file:// URLs can only refer to localhost'))
 
         self.path = path
 
         # leave the query string escaped
         for a in ('user', 'passwd', 'host', 'port',
                   'path', 'fragment'):
             v = getattr(self, a)
             if v is not None:
                 setattr(self, a, pycompat.urlunquote(v))
 
     def __repr__(self):
         attrs = []
         for a in ('scheme', 'user', 'passwd', 'host', 'port', 'path',
                   'query', 'fragment'):
             v = getattr(self, a)
             if v is not None:
                 attrs.append('%s: %r' % (a, v))
         return '<url %s>' % ', '.join(attrs)
 
     def __str__(self):
         r"""Join the URL's components back into a URL string.
 
         Examples:
 
         >>> str(url('http://user:pw@host:80/c:/bob?fo:oo#ba:ar'))
         'http://user:pw@host:80/c:/bob?fo:oo#ba:ar'
         >>> str(url('http://user:pw@host:80/?foo=bar&baz=42'))
         'http://user:pw@host:80/?foo=bar&baz=42'
         >>> str(url('http://user:pw@host:80/?foo=bar%3dbaz'))
         'http://user:pw@host:80/?foo=bar%3dbaz'
         >>> str(url('ssh://user:pw@[::1]:2200//home/joe#'))
         'ssh://user:pw@[::1]:2200//home/joe#'
         >>> str(url('http://localhost:80//'))
         'http://localhost:80//'
         >>> str(url('http://localhost:80/'))
         'http://localhost:80/'
         >>> str(url('http://localhost:80'))
         'http://localhost:80/'
         >>> str(url('bundle:foo'))
         'bundle:foo'
         >>> str(url('bundle://../foo'))
         'bundle:../foo'
         >>> str(url('path'))
         'path'
         >>> str(url('file:///tmp/foo/bar'))
         'file:///tmp/foo/bar'
         >>> str(url('file:///c:/tmp/foo/bar'))
         'file:///c:/tmp/foo/bar'
         >>> print url(r'bundle:foo\bar')
         bundle:foo\bar
         >>> print url(r'file:///D:\data\hg')
         file:///D:\data\hg
         """
         if self._localpath:
             s = self.path
             if self.scheme == 'bundle':
                 s = 'bundle:' + s
             if self.fragment:
                 s += '#' + self.fragment
             return s
 
         s = self.scheme + ':'
         if self.user or self.passwd or self.host:
             s += '//'
         elif self.scheme and (not self.path or self.path.startswith('/')
                               or hasdriveletter(self.path)):
             s += '//'
             if hasdriveletter(self.path):
                 s += '/'
         if self.user:
             s += urlreq.quote(self.user, safe=self._safechars)
         if self.passwd:
             s += ':' + urlreq.quote(self.passwd, safe=self._safechars)
         if self.user or self.passwd:
             s += '@'
         if self.host:
             if not (self.host.startswith('[') and self.host.endswith(']')):
                 s += urlreq.quote(self.host)
             else:
                 s += self.host
         if self.port:
             s += ':' + urlreq.quote(self.port)
         if self.host:
             s += '/'
         if self.path:
             # TODO: similar to the query string, we should not unescape the
             # path when we store it, the path might contain '%2f' = '/',
             # which we should *not* escape.
             s += urlreq.quote(self.path, safe=self._safepchars)
         if self.query:
             # we store the query in escaped form.
             s += '?' + self.query
         if self.fragment is not None:
             s += '#' + urlreq.quote(self.fragment, safe=self._safepchars)
         return s
 
     def authinfo(self):
         user, passwd = self.user, self.passwd
         try:
             self.user, self.passwd = None, None
             s = str(self)
         finally:
             self.user, self.passwd = user, passwd
         if not self.user:
             return (s, None)
         # authinfo[1] is passed to urllib2 password manager, and its
         # URIs must not contain credentials. The host is passed in the
         # URIs list because Python < 2.4.3 uses only that to search for
         # a password.
         return (s, (None, (s, self.host),
                     self.user, self.passwd or ''))
 
     def isabs(self):
         if self.scheme and self.scheme != 'file':
             return True # remote URL
         if hasdriveletter(self.path):
             return True # absolute for our purposes - can't be joined()
         if self.path.startswith(r'\\'):
             return True # Windows UNC path
         if self.path.startswith('/'):
             return True # POSIX-style
         return False
 
     def localpath(self):
         if self.scheme == 'file' or self.scheme == 'bundle':
             path = self.path or '/'
             # For Windows, we need to promote hosts containing drive
             # letters to paths with drive letters.
             if hasdriveletter(self._hostport):
                 path = self._hostport + '/' + self.path
             elif (self.host is not None and self.path
                   and not hasdriveletter(path)):
                 path = '/' + path
             return path
         return self._origpath
 
     def islocal(self):
         '''whether localpath will return something that posixfile can open'''
         return (not self.scheme or self.scheme == 'file'
                 or self.scheme == 'bundle')
 
 def hasscheme(path):
     return bool(url(path).scheme)
 
 def hasdriveletter(path):
     return path and path[1:2] == ':' and path[0:1].isalpha()
 
 def urllocalpath(path):
     return url(path, parsequery=False, parsefragment=False).localpath()
 
 def hidepassword(u):
     '''hide user credential in a url string'''
     u = url(u)
     if u.passwd:
         u.passwd = '***'
     return str(u)
 
 def removeauth(u):
     '''remove all authentication information from a url string'''
     u = url(u)
     u.user = u.passwd = None
     return str(u)
 
 def isatty(fp):
     try:
         return fp.isatty()
     except AttributeError:
         return False
 
 timecount = unitcountfn(
     (1, 1e3, _('%.0f s')),
     (100, 1, _('%.1f s')),
     (10, 1, _('%.2f s')),
     (1, 1, _('%.3f s')),
     (100, 0.001, _('%.1f ms')),
     (10, 0.001, _('%.2f ms')),
     (1, 0.001, _('%.3f ms')),
     (100, 0.000001, _('%.1f us')),
     (10, 0.000001, _('%.2f us')),
     (1, 0.000001, _('%.3f us')),
     (100, 0.000000001, _('%.1f ns')),
     (10, 0.000000001, _('%.2f ns')),
     (1, 0.000000001, _('%.3f ns')),
     )
 
 _timenesting = [0]
 
 def timed(func):
     '''Report the execution time of a function call to stderr.
 
     During development, use as a decorator when you need to measure
     the cost of a function, e.g. as follows:
 
     @util.timed
     def foo(a, b, c):
         pass
     '''
 
     def wrapper(*args, **kwargs):
         start = time.time()
         indent = 2
         _timenesting[0] += indent
         try:
             return func(*args, **kwargs)
         finally:
             elapsed = time.time() - start
             _timenesting[0] -= indent
             stderr.write('%s%s: %s\n' %
                          (' ' * _timenesting[0], func.__name__,
                           timecount(elapsed)))
     return wrapper
 
 _sizeunits = (('m', 2**20), ('k', 2**10), ('g', 2**30),
               ('kb', 2**10), ('mb', 2**20), ('gb', 2**30), ('b', 1))
 
 def sizetoint(s):
     '''Convert a space specifier to a byte count.
 
     >>> sizetoint('30')
     30
     >>> sizetoint('2.2kb')
     2252
     >>> sizetoint('6M')
     6291456
     '''
     t = s.strip().lower()
     try:
         for k, u in _sizeunits:
             if t.endswith(k):
                 return int(float(t[:-len(k)]) * u)
         return int(t)
     except ValueError:
         raise error.ParseError(_("couldn't parse size: %s") % s)
 
 class hooks(object):
     '''A collection of hook functions that can be used to extend a
     function's behavior. Hooks are called in lexicographic order,
     based on the names of their sources.'''
 
     def __init__(self):
         self._hooks = []
 
     def add(self, source, hook):
         self._hooks.append((source, hook))
 
     def __call__(self, *args):
         self._hooks.sort(key=lambda x: x[0])
         results = []
         for source, hook in self._hooks:
             results.append(hook(*args))
         return results
 
 def getstackframes(skip=0, line=' %-*s in %s\n', fileline='%s:%s'):
     '''Yields lines for a nicely formatted stacktrace.
     Skips the 'skip' last entries.
     Each file+linenumber is formatted according to fileline.
     Each line is formatted according to line.
     If line is None, it yields:
       length of longest filepath+line number,
       filepath+linenumber,
       function
 
     Not be used in production code but very convenient while developing.
     '''
     entries = [(fileline % (fn, ln), func)
         for fn, ln, func, _text in traceback.extract_stack()[:-skip - 1]]
     if entries:
         fnmax = max(len(entry[0]) for entry in entries)
         for fnln, func in entries:
             if line is None:
                 yield (fnmax, fnln, func)
             else:
                 yield line % (fnmax, fnln, func)
 
 def debugstacktrace(msg='stacktrace', skip=0, f=stderr, otherf=stdout):
     '''Writes a message to f (stderr) with a nicely formatted stacktrace.
     Skips the 'skip' last entries. By default it will flush stdout first.
     It can be used everywhere and intentionally does not require an ui object.
     Not be used in production code but very convenient while developing.
     '''
     if otherf:
         otherf.flush()
     f.write('%s at:\n' % msg)
     for line in getstackframes(skip + 1):
         f.write(line)
     f.flush()
 
 class dirs(object):
     '''a multiset of directory names from a dirstate or manifest'''
 
     def __init__(self, map, skip=None):
         self._dirs = {}
         addpath = self.addpath
         if safehasattr(map, 'iteritems') and skip is not None:
             for f, s in map.iteritems():
                 if s[0] != skip:
                     addpath(f)
         else:
             for f in map:
                 addpath(f)
 
     def addpath(self, path):
         dirs = self._dirs
         for base in finddirs(path):
             if base in dirs:
                 dirs[base] += 1
                 return
             dirs[base] = 1
 
     def delpath(self, path):
         dirs = self._dirs
         for base in finddirs(path):
             if dirs[base] > 1:
                 dirs[base] -= 1
                 return
             del dirs[base]
 
     def __iter__(self):
         return self._dirs.iterkeys()
 
     def __contains__(self, d):
         return d in self._dirs
 
 if safehasattr(parsers, 'dirs'):
     dirs = parsers.dirs
 
 def finddirs(path):
     pos = path.rfind('/')
     while pos != -1:
         yield path[:pos]
         pos = path.rfind('/', 0, pos)
 
 class ctxmanager(object):
     '''A context manager for use in 'with' blocks to allow multiple
     contexts to be entered at once.  This is both safer and more
     flexible than contextlib.nested.
 
     Once Mercurial supports Python 2.7+, this will become mostly
     unnecessary.
     '''
 
     def __init__(self, *args):
         '''Accepts a list of no-argument functions that return context
         managers.  These will be invoked at __call__ time.'''
         self._pending = args
         self._atexit = []
 
     def __enter__(self):
         return self
 
     def enter(self):
         '''Create and enter context managers in the order in which they were
         passed to the constructor.'''
         values = []
         for func in self._pending:
             obj = func()
             values.append(obj.__enter__())
             self._atexit.append(obj.__exit__)
         del self._pending
         return values
 
     def atexit(self, func, *args, **kwargs):
         '''Add a function to call when this context manager exits.  The
         ordering of multiple atexit calls is unspecified, save that
         they will happen before any __exit__ functions.'''
         def wrapper(exc_type, exc_val, exc_tb):
             func(*args, **kwargs)
         self._atexit.append(wrapper)
         return func
 
     def __exit__(self, exc_type, exc_val, exc_tb):
         '''Context managers are exited in the reverse order from which
         they were created.'''
         received = exc_type is not None
         suppressed = False
         pending = None
         self._atexit.reverse()
         for exitfunc in self._atexit:
             try:
                 if exitfunc(exc_type, exc_val, exc_tb):
                     suppressed = True
                     exc_type = None
                     exc_val = None
                     exc_tb = None
             except BaseException:
                 pending = sys.exc_info()
                 exc_type, exc_val, exc_tb = pending = sys.exc_info()
         del self._atexit
         if pending:
             raise exc_val
         return received and suppressed
 
 # compression code
 
 class compressormanager(object):
     """Holds registrations of various compression engines.
 
     This class essentially abstracts the differences between compression
     engines to allow new compression formats to be added easily, possibly from
     extensions.
 
     Compressors are registered against the global instance by calling its
     ``register()`` method.
     """
     def __init__(self):
         self._engines = {}
         # Bundle spec human name to engine name.
         self._bundlenames = {}
         # Internal bundle identifier to engine name.
         self._bundletypes = {}
 
     def __getitem__(self, key):
         return self._engines[key]
 
     def __contains__(self, key):
         return key in self._engines
 
     def __iter__(self):
         return iter(self._engines.keys())
 
     def register(self, engine):
         """Register a compression engine with the manager.
 
         The argument must be a ``compressionengine`` instance.
         """
         if not isinstance(engine, compressionengine):
             raise ValueError(_('argument must be a compressionengine'))
 
         name = engine.name()
 
         if name in self._engines:
             raise error.Abort(_('compression engine %s already registered') %
                               name)
 
         bundleinfo = engine.bundletype()
         if bundleinfo:
             bundlename, bundletype = bundleinfo
 
             if bundlename in self._bundlenames:
                 raise error.Abort(_('bundle name %s already registered') %
                                   bundlename)
             if bundletype in self._bundletypes:
                 raise error.Abort(_('bundle type %s already registered by %s') %
                                   (bundletype, self._bundletypes[bundletype]))
 
             # No external facing name declared.
             if bundlename:
                 self._bundlenames[bundlename] = name
 
             self._bundletypes[bundletype] = name
 
         self._engines[name] = engine
 
     @property
     def supportedbundlenames(self):
         return set(self._bundlenames.keys())
 
     @property
     def supportedbundletypes(self):
         return set(self._bundletypes.keys())
 
     def forbundlename(self, bundlename):
         """Obtain a compression engine registered to a bundle name.
 
         Will raise KeyError if the bundle type isn't registered.
 
         Will abort if the engine is known but not available.
         """
         engine = self._engines[self._bundlenames[bundlename]]
         if not engine.available():
             raise error.Abort(_('compression engine %s could not be loaded') %
                               engine.name())
         return engine
 
     def forbundletype(self, bundletype):
         """Obtain a compression engine registered to a bundle type.
 
         Will raise KeyError if the bundle type isn't registered.
 
         Will abort if the engine is known but not available.
         """
         engine = self._engines[self._bundletypes[bundletype]]
         if not engine.available():
             raise error.Abort(_('compression engine %s could not be loaded') %
                               engine.name())
         return engine
 
 compengines = compressormanager()
 
 class compressionengine(object):
     """Base class for compression engines.
 
     Compression engines must implement the interface defined by this class.
     """
     def name(self):
         """Returns the name of the compression engine.
 
         This is the key the engine is registered under.
 
         This method must be implemented.
         """
         raise NotImplementedError()
 
     def available(self):
         """Whether the compression engine is available.
 
         The intent of this method is to allow optional compression engines
         that may not be available in all installations (such as engines relying
         on C extensions that may not be present).
         """
         return True
 
     def bundletype(self):
         """Describes bundle identifiers for this engine.
 
         If this compression engine isn't supported for bundles, returns None.
 
         If this engine can be used for bundles, returns a 2-tuple of strings of
         the user-facing "bundle spec" compression name and an internal
         identifier used to denote the compression format within bundles. To
         exclude the name from external usage, set the first element to ``None``.
 
         If bundle compression is supported, the class must also implement
         ``compressstream`` and `decompressorreader``.
         """
         return None
 
     def compressstream(self, it, opts=None):
         """Compress an iterator of chunks.
 
         The method receives an iterator (ideally a generator) of chunks of
         bytes to be compressed. It returns an iterator (ideally a generator)
         of bytes of chunks representing the compressed output.
 
         Optionally accepts an argument defining how to perform compression.
         Each engine treats this argument differently.
         """
         raise NotImplementedError()
 
     def decompressorreader(self, fh):
         """Perform decompression on a file object.
 
         Argument is an object with a ``read(size)`` method that returns
         compressed data. Return value is an object with a ``read(size)`` that
         returns uncompressed data.
         """
         raise NotImplementedError()
 
 class _zlibengine(compressionengine):
     def name(self):
         return 'zlib'
 
     def bundletype(self):
         return 'gzip', 'GZ'
 
     def compressstream(self, it, opts=None):
         opts = opts or {}
 
         z = zlib.compressobj(opts.get('level', -1))
         for chunk in it:
             data = z.compress(chunk)
             # Not all calls to compress emit data. It is cheaper to inspect
             # here than to feed empty chunks through generator.
             if data:
                 yield data
 
         yield z.flush()
 
     def decompressorreader(self, fh):
         def gen():
             d = zlib.decompressobj()
             for chunk in filechunkiter(fh):
                 while chunk:
                     # Limit output size to limit memory.
                     yield d.decompress(chunk, 2 ** 18)
                     chunk = d.unconsumed_tail
 
         return chunkbuffer(gen())
 
 compengines.register(_zlibengine())
 
 class _bz2engine(compressionengine):
     def name(self):
         return 'bz2'
 
     def bundletype(self):
         return 'bzip2', 'BZ'
 
     def compressstream(self, it, opts=None):
         opts = opts or {}
         z = bz2.BZ2Compressor(opts.get('level', 9))
         for chunk in it:
             data = z.compress(chunk)
             if data:
                 yield data
 
         yield z.flush()
 
     def decompressorreader(self, fh):
         def gen():
             d = bz2.BZ2Decompressor()
             for chunk in filechunkiter(fh):
                 yield d.decompress(chunk)
 
         return chunkbuffer(gen())
 
 compengines.register(_bz2engine())
 
 class _truncatedbz2engine(compressionengine):
     def name(self):
         return 'bz2truncated'
 
     def bundletype(self):
         return None, '_truncatedBZ'
 
     # We don't implement compressstream because it is hackily handled elsewhere.
 
     def decompressorreader(self, fh):
         def gen():
             # The input stream doesn't have the 'BZ' header. So add it back.
             d = bz2.BZ2Decompressor()
             d.decompress('BZ')
             for chunk in filechunkiter(fh):
                 yield d.decompress(chunk)
 
         return chunkbuffer(gen())
 
 compengines.register(_truncatedbz2engine())
 
 class _noopengine(compressionengine):
     def name(self):
         return 'none'
 
     def bundletype(self):
         return 'none', 'UN'
 
     def compressstream(self, it, opts=None):
         return it
 
     def decompressorreader(self, fh):
         return fh
 
 compengines.register(_noopengine())
 
 class _zstdengine(compressionengine):
     def name(self):
         return 'zstd'
 
     @propertycache
     def _module(self):
         # Not all installs have the zstd module available. So defer importing
         # until first access.
         try:
             from . import zstd
             # Force delayed import.
             zstd.__version__
             return zstd
         except ImportError:
             return None
 
     def available(self):
         return bool(self._module)
 
     def bundletype(self):
         return 'zstd', 'ZS'
 
     def compressstream(self, it, opts=None):
         opts = opts or {}
         # zstd level 3 is almost always significantly faster than zlib
         # while providing no worse compression. It strikes a good balance
         # between speed and compression.
         level = opts.get('level', 3)
 
         zstd = self._module
         z = zstd.ZstdCompressor(level=level).compressobj()
         for chunk in it:
             data = z.compress(chunk)
             if data:
                 yield data
 
         yield z.flush()
 
     def decompressorreader(self, fh):
         zstd = self._module
         dctx = zstd.ZstdDecompressor()
         return chunkbuffer(dctx.read_from(fh))
 
 compengines.register(_zstdengine())
 
 # convenient shortcut
 dst = debugstacktrace