def subrelpath(sub):
    """return path to this subrepo as seen from outermost repo"""
    if util.safehasattr(sub, '_relpath'):
        return sub._relpath
    if not util.safehasattr(sub, '_repo'):
        return sub._path
    return reporelpath(sub._repo)

def json(obj):
    if obj is None or obj is False or obj is True:
        return {None: 'null', False: 'false', True: 'true'}[obj]
    elif isinstance(obj, int) or isinstance(obj, float):
        return str(obj)
    elif isinstance(obj, str):
        u = unicode(obj, encoding.encoding, 'replace')
        return '"%s"' % jsonescape(u)
    elif isinstance(obj, unicode):
        return '"%s"' % jsonescape(obj)
    elif util.safehasattr(obj, 'keys'):
        out = []
        for k, v in sorted(obj.iteritems()):
            s = '%s: %s' % (json(k), json(v))
            out.append(s)
        return '{' + ', '.join(out) + '}'
    elif util.safehasattr(obj, '__iter__'):
        out = []
        for i in obj:
            out.append(json(i))
        return '[' + ', '.join(out) + ']'
    elif util.safehasattr(obj, '__call__'):
        return json(obj())
    else:
        raise TypeError('cannot encode type %s' % obj.__class__.__name__)

def makefileobj(repo, pat, node=None, desc=None, total=None,
                seqno=None, revwidth=None, mode='wb', pathname=None):

    writable = mode not in ('r', 'rb')

    if not pat or pat == '-':
        fp = writable and repo.ui.fout or repo.ui.fin
        if util.safehasattr(fp, 'fileno'):
            return os.fdopen(os.dup(fp.fileno()), mode)
        else:
            # if this fp can't be duped properly, return
            # a dummy object that can be closed
            class wrappedfileobj(object):
                noop = lambda x: None
                def __init__(self, f):
                    self.f = f
                def __getattr__(self, attr):
                    if attr == 'close':
                        return self.noop
                    else:
                        return getattr(self.f, attr)

            return wrappedfileobj(fp)
    if util.safehasattr(pat, 'write') and writable:
        return pat
    if util.safehasattr(pat, 'read') and 'r' in mode:
        return pat
    return open(makefilename(repo, pat, node, desc, total, seqno, revwidth,
                              pathname),
                mode)

def moduleversion(module):
    '''return version information from given module as a string'''
    if (util.safehasattr(module, 'getversion')
          and callable(module.getversion)):
        version = module.getversion()
    elif util.safehasattr(module, '__version__'):
        version = module.__version__
    else:
        version = ''
    if isinstance(version, (list, tuple)):
        version = '.'.join(str(o) for o in version)
    return version

def remoteui(src, opts):
    "build a remote ui from ui or repo and opts"
    if util.safehasattr(src, "baseui"):  # looks like a repository
        dst = src.baseui.copy()  # drop repo-specific config
        src = src.ui  # copy target options from repo
    else:  # assume it's a global ui object
        dst = src.copy()  # keep all global options

    # copy ssh-specific options
    for o in "ssh", "remotecmd":
        v = opts.get(o) or src.config("ui", o)
        if v:
            dst.setconfig("ui", o, v, "copied")

    # copy bundle-specific options
    r = src.config("bundle", "mainreporoot")
    if r:
        dst.setconfig("bundle", "mainreporoot", r, "copied")

    # copy selected local settings to the remote ui
    for sect in ("auth", "hostfingerprints", "http_proxy"):
        for key, val in src.configitems(sect):
            dst.setconfig(sect, key, val, "copied")
    v = src.config("web", "cacerts")
    if v:
        dst.setconfig("web", "cacerts", util.expandpath(v), "copied")

    return dst

def reporelpath(repo):
    """return path to this (sub)repo as seen from outermost repo"""
    parent = repo
    while util.safehasattr(parent, '_subparent'):
        parent = parent._subparent
    p = parent.root.rstrip(os.sep)
    return repo.root[len(p) + 1:]

def unbundle(repo, proto, heads):
    their_heads = decodelist(heads)

    try:
        proto.redirect()

        exchange.check_heads(repo, their_heads, 'preparing changes')

        # write bundle data to temporary file because it can be big
        fd, tempname = tempfile.mkstemp(prefix='hg-unbundle-')
        fp = os.fdopen(fd, 'wb+')
        r = 0
        try:
            proto.getfile(fp)
            fp.seek(0)
            gen = exchange.readbundle(repo.ui, fp, None)
            r = exchange.unbundle(repo, gen, their_heads, 'serve',
                                  proto._client())
            if util.safehasattr(r, 'addpart'):
                # The return looks streameable, we are in the bundle2 case and
                # should return a stream.
                return streamres(r.getchunks())
            return pushres(r)

        finally:
            fp.close()
            os.unlink(tempname)
    except bundle2.UnknownPartError, exc:
            bundler = bundle2.bundle20(repo.ui)
            part = bundle2.bundlepart('B2X:ERROR:UNKNOWNPART',
                                      [('parttype', str(exc))])
            bundler.addpart(part)
            return streamres(bundler.getchunks())

def runsymbol(context, mapping, key):
    v = mapping.get(key)
    if v is None:
        v = context._defaults.get(key, '')
    if util.safehasattr(v, '__call__'):
        return v(**mapping)
    return v

    def helptopic(name):
        for names, header, doc in helptable:
            if name in names:
                break
        else:
            raise error.UnknownCommand(name)

        rst = [minirst.section(header)]

        # description
        if not doc:
            rst.append("    %s\n" % _("(no help text available)"))
        if util.safehasattr(doc, '__call__'):
            rst += ["    %s\n" % l for l in doc().splitlines()]

        if not ui.verbose:
            omitted = (_('use "hg help -v %s" to show more complete help') %
                       name)
            indicateomitted(rst, omitted)

        try:
            cmdutil.findcmd(name, commands.table)
            rst.append(_('\nuse "hg help -c %s" to see help for '
                       'the %s command\n') % (name, name))
        except error.UnknownCommand:
            pass
        return rst

def wrapcommand(table, command, wrapper):
    '''Wrap the command named `command' in table

    Replace command in the command table with wrapper. The wrapped command will
    be inserted into the command table specified by the table argument.

    The wrapper will be called like

      wrapper(orig, *args, **kwargs)

    where orig is the original (wrapped) function, and *args, **kwargs
    are the arguments passed to it.
    '''
    assert util.safehasattr(wrapper, '__call__')
    aliases, entry = cmdutil.findcmd(command, table)
    for alias, e in table.iteritems():
        if e is entry:
            key = alias
            break

    origfn = entry[0]
    def wrap(*args, **kwargs):
        return util.checksignature(wrapper)(
            util.checksignature(origfn), *args, **kwargs)

    wrap.__doc__ = getattr(origfn, '__doc__')
    wrap.__module__ = getattr(origfn, '__module__')

    newentry = list(entry)
    newentry[0] = wrap
    table[key] = tuple(newentry)
    return entry

def unbundle(repo, proto, heads):
    their_heads = decodelist(heads)

    try:
        proto.redirect()

        exchange.check_heads(repo, their_heads, "preparing changes")

        # write bundle data to temporary file because it can be big
        fd, tempname = tempfile.mkstemp(prefix="hg-unbundle-")
        fp = os.fdopen(fd, "wb+")
        r = 0
        try:
            proto.getfile(fp)
            fp.seek(0)
            gen = exchange.readbundle(repo.ui, fp, None)
            r = exchange.unbundle(repo, gen, their_heads, "serve", proto._client())
            if util.safehasattr(r, "addpart"):
                # The return looks streameable, we are in the bundle2 case and
                # should return a stream.
                return streamres(r.getchunks())
            return pushres(r)

        finally:
            fp.close()
            os.unlink(tempname)
    except error.BundleValueError, exc:
        bundler = bundle2.bundle20(repo.ui)
        errpart = bundler.newpart("B2X:ERROR:UNSUPPORTEDCONTENT")
        if exc.parttype is not None:
            errpart.addparam("parttype", exc.parttype)
        if exc.params:
            errpart.addparam("params", "\0".join(exc.params))
        return streamres(bundler.getchunks())

def remoteui(src, opts):
    'build a remote ui from ui or repo and opts'
    if util.safehasattr(src, 'baseui'): # looks like a repository
        dst = src.baseui.copy() # drop repo-specific config
        src = src.ui # copy target options from repo
    else: # assume it's a global ui object
        dst = src.copy() # keep all global options

    # copy ssh-specific options
    for o in 'ssh', 'remotecmd':
        v = opts.get(o) or src.config('ui', o)
        if v:
            dst.setconfig("ui", o, v)

    # copy bundle-specific options
    r = src.config('bundle', 'mainreporoot')
    if r:
        dst.setconfig('bundle', 'mainreporoot', r)

    # copy selected local settings to the remote ui
    for sect in ('auth', 'hostfingerprints', 'http_proxy'):
        for key, val in src.configitems(sect):
            dst.setconfig(sect, key, val)
    v = src.config('web', 'cacerts')
    if v:
        dst.setconfig('web', 'cacerts', util.expandpath(v))

    return dst

def stringify(thing):
    """:stringify: Any type. Turns the value into text by converting values into
    text and concatenating them.
    """
    if util.safehasattr(thing, '__iter__') and not isinstance(thing, str):
        return "".join([stringify(t) for t in thing if t is not None])
    return str(thing)

def pushkey(repo, proto, namespace, key, old, new):
    # compatibility with pre-1.8 clients which were accidentally
    # sending raw binary nodes rather than utf-8-encoded hex
    if len(new) == 20 and new.encode('string-escape') != new:
        # looks like it could be a binary node
        try:
            new.decode('utf-8')
            new = encoding.tolocal(new) # but cleanly decodes as UTF-8
        except UnicodeDecodeError:
            pass # binary, leave unmodified
    else:
        new = encoding.tolocal(new) # normal path

    if util.safehasattr(proto, 'restore'):

        proto.redirect()

        try:
            r = repo.pushkey(encoding.tolocal(namespace), encoding.tolocal(key),
                             encoding.tolocal(old), new) or False
        except util.Abort:
            r = False

        output = proto.restore()

        return '%s\n%s' % (int(r), output)

    r = repo.pushkey(encoding.tolocal(namespace), encoding.tolocal(key),
                     encoding.tolocal(old), new)
    return '%s\n' % int(r)

def unbundle(repo, cg, heads, source, url):
    """Apply a bundle to a repo.

    this function makes sure the repo is locked during the application and have
    mechanism to check that no push race occurred between the creation of the
    bundle and its application.

    If the push was raced as PushRaced exception is raised."""
    r = 0
    # need a transaction when processing a bundle2 stream
    tr = None
    lock = repo.lock()
    try:
        check_heads(repo, heads, 'uploading changes')
        # push can proceed
        if util.safehasattr(cg, 'params'):
            try:
                tr = repo.transaction('unbundle')
                tr.hookargs['source'] = source
                tr.hookargs['url'] = url
                tr.hookargs['bundle2-exp'] = '1'
                r = bundle2.processbundle(repo, cg, lambda: tr).reply
                cl = repo.unfiltered().changelog
                p = cl.writepending() and repo.root or ""
                repo.hook('b2x-pretransactionclose', throw=True, pending=p,
                          **tr.hookargs)
                tr.close()
                hookargs = dict(tr.hookargs)
                def runhooks():
                    repo.hook('b2x-transactionclose', **hookargs)
                repo._afterlock(runhooks)
            except Exception, exc:
                exc.duringunbundle2 = True
                raise
        else:

    def unbundle(self, cg, heads, source):
        '''Send cg (a readable file-like object representing the
        changegroup to push, typically a chunkbuffer object) to the
        remote server as a bundle.

        When pushing a bundle10 stream, return an integer indicating the
        result of the push (see localrepository.addchangegroup()).

        When pushing a bundle20 stream, return a bundle20 stream.'''

        if heads != ['force'] and self.capable('unbundlehash'):
            heads = encodelist(['hashed',
                                util.sha1(''.join(sorted(heads))).digest()])
        else:
            heads = encodelist(heads)

        if util.safehasattr(cg, 'deltaheader'):
            # this a bundle10, do the old style call sequence
            ret, output = self._callpush("unbundle", cg, heads=heads)
            if ret == "":
                raise error.ResponseError(
                    _('push failed:'), output)
            try:
                ret = int(ret)
            except ValueError:
                raise error.ResponseError(
                    _('push failed (unexpected response):'), ret)

            for l in output.splitlines(True):
                self.ui.status(_('remote: '), l)
        else:
            # bundle2 push. Send a stream, fetch a stream.
            stream = self._calltwowaystream('unbundle', cg, heads=heads)
            ret = bundle2.unbundle20(self.ui, stream)
        return ret

def _checkshellalias(lui, ui, args):
    norepo = commands.norepo
    options = {}

    try:
        args = fancyopts.fancyopts(args, commands.globalopts, options)
    except fancyopts.getopt.GetoptError:
        return

    if not args:
        return

    cmdtable = commands.table.copy()
    addaliases(lui, cmdtable)

    cmd = args[0]
    try:
        aliases, entry = cmdutil.findcmd(cmd, cmdtable, lui.config("ui", "strict"))
    except (error.AmbiguousCommand, error.UnknownCommand):
        commands.norepo = norepo
        return

    cmd = aliases[0]
    fn = entry[0]

    if cmd and util.safehasattr(fn, 'shell'):
        d = lambda: fn(ui, *args[1:])
        return lambda: runcommand(lui, None, cmd, args[:1], ui, options, d, [], {})

    commands.norepo = norepo

 def copies(self, c2):
     if not util.safehasattr(self, "_copycache"):
         self._copycache = {}
     sc2 = str(c2)
     if sc2 not in self._copycache:
         self._copycache[sc2] = copies.pathcopies(c2)
     return self._copycache[sc2]

def _exthook(ui, repo, name, cmd, args, throw):
    ui.note(_("running hook %s: %s\n") % (name, cmd))

    starttime = time.time()
    env = {}
    for k, v in args.iteritems():
        if util.safehasattr(v, '__call__'):
            v = v()
        if isinstance(v, dict):
            # make the dictionary element order stable across Python
            # implementations
            v = ('{' +
                 ', '.join('%r: %r' % i for i in sorted(v.iteritems())) +
                 '}')
        env['HG_' + k.upper()] = v

    if repo:
        cwd = repo.root
    else:
        cwd = os.getcwd()
    if 'HG_URL' in env and env['HG_URL'].startswith('remote:http'):
        r = util.system(cmd, environ=env, cwd=cwd, out=ui)
    else:
        r = util.system(cmd, environ=env, cwd=cwd, out=ui.fout)

    duration = time.time() - starttime
    ui.log('exthook', 'exthook-%s: %s finished in %0.2f seconds\n',
           name, cmd, duration)
    if r:
        desc, r = util.explainexit(r)
        if throw:
            raise util.Abort(_('%s hook %s') % (name, desc))
        ui.warn(_('warning: %s hook %s\n') % (name, desc))
    return r

def _flatten(thing):
    '''yield a single stream from a possibly nested set of iterators'''
    if isinstance(thing, str):
        yield thing
    elif not util.safehasattr(thing, '__iter__'):
        if thing is not None:
            yield str(thing)
    else:
        for i in thing:
            if isinstance(i, str):
                yield i
            elif not util.safehasattr(i, '__iter__'):
                if i is not None:
                    yield str(i)
            elif i is not None:
                for j in _flatten(i):
                    yield j