diff -r 5ff1fc726848 -r c6bca38c1cbf eggs/mercurial-1.7.3-py2.6-linux-x86_64.egg/mercurial/localrepo.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/eggs/mercurial-1.7.3-py2.6-linux-x86_64.egg/mercurial/localrepo.py	Sat Jan 08 11:20:57 2011 +0530
@@ -0,0 +1,1906 @@
+# localrepo.py - read/write repository class for mercurial
+#
+# Copyright 2005-2007 Matt Mackall <mpm@selenic.com>
+#
+# This software may be used and distributed according to the terms of the
+# GNU General Public License version 2 or any later version.
+
+from node import bin, hex, nullid, nullrev, short
+from i18n import _
+import repo, changegroup, subrepo, discovery, pushkey
+import changelog, dirstate, filelog, manifest, context
+import lock, transaction, store, encoding
+import util, extensions, hook, error
+import match as matchmod
+import merge as mergemod
+import tags as tagsmod
+import url as urlmod
+from lock import release
+import weakref, errno, os, time, inspect
+propertycache = util.propertycache
+
+class localrepository(repo.repository):
+    capabilities = set(('lookup', 'changegroupsubset', 'branchmap', 'pushkey'))
+    supportedformats = set(('revlogv1', 'parentdelta'))
+    supported = supportedformats | set(('store', 'fncache', 'shared',
+                                        'dotencode'))
+
+    def __init__(self, baseui, path=None, create=0):
+        repo.repository.__init__(self)
+        self.root = os.path.realpath(util.expandpath(path))
+        self.path = os.path.join(self.root, ".hg")
+        self.origroot = path
+        self.auditor = util.path_auditor(self.root, self._checknested)
+        self.opener = util.opener(self.path)
+        self.wopener = util.opener(self.root)
+        self.baseui = baseui
+        self.ui = baseui.copy()
+
+        try:
+            self.ui.readconfig(self.join("hgrc"), self.root)
+            extensions.loadall(self.ui)
+        except IOError:
+            pass
+
+        if not os.path.isdir(self.path):
+            if create:
+                if not os.path.exists(path):
+                    util.makedirs(path)
+                os.mkdir(self.path)
+                requirements = ["revlogv1"]
+                if self.ui.configbool('format', 'usestore', True):
+                    os.mkdir(os.path.join(self.path, "store"))
+                    requirements.append("store")
+                    if self.ui.configbool('format', 'usefncache', True):
+                        requirements.append("fncache")
+                        if self.ui.configbool('format', 'dotencode', True):
+                            requirements.append('dotencode')
+                    # create an invalid changelog
+                    self.opener("00changelog.i", "a").write(
+                        '\0\0\0\2' # represents revlogv2
+                        ' dummy changelog to prevent using the old repo layout'
+                    )
+                if self.ui.configbool('format', 'parentdelta', False):
+                    requirements.append("parentdelta")
+            else:
+                raise error.RepoError(_("repository %s not found") % path)
+        elif create:
+            raise error.RepoError(_("repository %s already exists") % path)
+        else:
+            # find requirements
+            requirements = set()
+            try:
+                requirements = set(self.opener("requires").read().splitlines())
+            except IOError, inst:
+                if inst.errno != errno.ENOENT:
+                    raise
+            for r in requirements - self.supported:
+                raise error.RepoError(_("requirement '%s' not supported") % r)
+
+        self.sharedpath = self.path
+        try:
+            s = os.path.realpath(self.opener("sharedpath").read())
+            if not os.path.exists(s):
+                raise error.RepoError(
+                    _('.hg/sharedpath points to nonexistent directory %s') % s)
+            self.sharedpath = s
+        except IOError, inst:
+            if inst.errno != errno.ENOENT:
+                raise
+
+        self.store = store.store(requirements, self.sharedpath, util.opener)
+        self.spath = self.store.path
+        self.sopener = self.store.opener
+        self.sjoin = self.store.join
+        self.opener.createmode = self.store.createmode
+        self._applyrequirements(requirements)
+        if create:
+            self._writerequirements()
+
+        # These two define the set of tags for this repository.  _tags
+        # maps tag name to node; _tagtypes maps tag name to 'global' or
+        # 'local'.  (Global tags are defined by .hgtags across all
+        # heads, and local tags are defined in .hg/localtags.)  They
+        # constitute the in-memory cache of tags.
+        self._tags = None
+        self._tagtypes = None
+
+        self._branchcache = None  # in UTF-8
+        self._branchcachetip = None
+        self.nodetagscache = None
+        self.filterpats = {}
+        self._datafilters = {}
+        self._transref = self._lockref = self._wlockref = None
+
+    def _applyrequirements(self, requirements):
+        self.requirements = requirements
+        self.sopener.options = {}
+        if 'parentdelta' in requirements:
+            self.sopener.options['parentdelta'] = 1
+
+    def _writerequirements(self):
+        reqfile = self.opener("requires", "w")
+        for r in self.requirements:
+            reqfile.write("%s\n" % r)
+        reqfile.close()
+
+    def _checknested(self, path):
+        """Determine if path is a legal nested repository."""
+        if not path.startswith(self.root):
+            return False
+        subpath = path[len(self.root) + 1:]
+
+        # XXX: Checking against the current working copy is wrong in
+        # the sense that it can reject things like
+        #
+        #   $ hg cat -r 10 sub/x.txt
+        #
+        # if sub/ is no longer a subrepository in the working copy
+        # parent revision.
+        #
+        # However, it can of course also allow things that would have
+        # been rejected before, such as the above cat command if sub/
+        # is a subrepository now, but was a normal directory before.
+        # The old path auditor would have rejected by mistake since it
+        # panics when it sees sub/.hg/.
+        #
+        # All in all, checking against the working copy seems sensible
+        # since we want to prevent access to nested repositories on
+        # the filesystem *now*.
+        ctx = self[None]
+        parts = util.splitpath(subpath)
+        while parts:
+            prefix = os.sep.join(parts)
+            if prefix in ctx.substate:
+                if prefix == subpath:
+                    return True
+                else:
+                    sub = ctx.sub(prefix)
+                    return sub.checknested(subpath[len(prefix) + 1:])
+            else:
+                parts.pop()
+        return False
+
+
+    @propertycache
+    def changelog(self):
+        c = changelog.changelog(self.sopener)
+        if 'HG_PENDING' in os.environ:
+            p = os.environ['HG_PENDING']
+            if p.startswith(self.root):
+                c.readpending('00changelog.i.a')
+        self.sopener.options['defversion'] = c.version
+        return c
+
+    @propertycache
+    def manifest(self):
+        return manifest.manifest(self.sopener)
+
+    @propertycache
+    def dirstate(self):
+        return dirstate.dirstate(self.opener, self.ui, self.root)
+
+    def __getitem__(self, changeid):
+        if changeid is None:
+            return context.workingctx(self)
+        return context.changectx(self, changeid)
+
+    def __contains__(self, changeid):
+        try:
+            return bool(self.lookup(changeid))
+        except error.RepoLookupError:
+            return False
+
+    def __nonzero__(self):
+        return True
+
+    def __len__(self):
+        return len(self.changelog)
+
+    def __iter__(self):
+        for i in xrange(len(self)):
+            yield i
+
+    def url(self):
+        return 'file:' + self.root
+
+    def hook(self, name, throw=False, **args):
+        return hook.hook(self.ui, self, name, throw, **args)
+
+    tag_disallowed = ':\r\n'
+
+    def _tag(self, names, node, message, local, user, date, extra={}):
+        if isinstance(names, str):
+            allchars = names
+            names = (names,)
+        else:
+            allchars = ''.join(names)
+        for c in self.tag_disallowed:
+            if c in allchars:
+                raise util.Abort(_('%r cannot be used in a tag name') % c)
+
+        branches = self.branchmap()
+        for name in names:
+            self.hook('pretag', throw=True, node=hex(node), tag=name,
+                      local=local)
+            if name in branches:
+                self.ui.warn(_("warning: tag %s conflicts with existing"
+                " branch name\n") % name)
+
+        def writetags(fp, names, munge, prevtags):
+            fp.seek(0, 2)
+            if prevtags and prevtags[-1] != '\n':
+                fp.write('\n')
+            for name in names:
+                m = munge and munge(name) or name
+                if self._tagtypes and name in self._tagtypes:
+                    old = self._tags.get(name, nullid)
+                    fp.write('%s %s\n' % (hex(old), m))
+                fp.write('%s %s\n' % (hex(node), m))
+            fp.close()
+
+        prevtags = ''
+        if local:
+            try:
+                fp = self.opener('localtags', 'r+')
+            except IOError:
+                fp = self.opener('localtags', 'a')
+            else:
+                prevtags = fp.read()
+
+            # local tags are stored in the current charset
+            writetags(fp, names, None, prevtags)
+            for name in names:
+                self.hook('tag', node=hex(node), tag=name, local=local)
+            return
+
+        try:
+            fp = self.wfile('.hgtags', 'rb+')
+        except IOError:
+            fp = self.wfile('.hgtags', 'ab')
+        else:
+            prevtags = fp.read()
+
+        # committed tags are stored in UTF-8
+        writetags(fp, names, encoding.fromlocal, prevtags)
+
+        if '.hgtags' not in self.dirstate:
+            self[None].add(['.hgtags'])
+
+        m = matchmod.exact(self.root, '', ['.hgtags'])
+        tagnode = self.commit(message, user, date, extra=extra, match=m)
+
+        for name in names:
+            self.hook('tag', node=hex(node), tag=name, local=local)
+
+        return tagnode
+
+    def tag(self, names, node, message, local, user, date):
+        '''tag a revision with one or more symbolic names.
+
+        names is a list of strings or, when adding a single tag, names may be a
+        string.
+
+        if local is True, the tags are stored in a per-repository file.
+        otherwise, they are stored in the .hgtags file, and a new
+        changeset is committed with the change.
+
+        keyword arguments:
+
+        local: whether to store tags in non-version-controlled file
+        (default False)
+
+        message: commit message to use if committing
+
+        user: name of user to use if committing
+
+        date: date tuple to use if committing'''
+
+        if not local:
+            for x in self.status()[:5]:
+                if '.hgtags' in x:
+                    raise util.Abort(_('working copy of .hgtags is changed '
+                                       '(please commit .hgtags manually)'))
+
+        self.tags() # instantiate the cache
+        self._tag(names, node, message, local, user, date)
+
+    def tags(self):
+        '''return a mapping of tag to node'''
+        if self._tags is None:
+            (self._tags, self._tagtypes) = self._findtags()
+
+        return self._tags
+
+    def _findtags(self):
+        '''Do the hard work of finding tags.  Return a pair of dicts
+        (tags, tagtypes) where tags maps tag name to node, and tagtypes
+        maps tag name to a string like \'global\' or \'local\'.
+        Subclasses or extensions are free to add their own tags, but
+        should be aware that the returned dicts will be retained for the
+        duration of the localrepo object.'''
+
+        # XXX what tagtype should subclasses/extensions use?  Currently
+        # mq and bookmarks add tags, but do not set the tagtype at all.
+        # Should each extension invent its own tag type?  Should there
+        # be one tagtype for all such "virtual" tags?  Or is the status
+        # quo fine?
+
+        alltags = {}                    # map tag name to (node, hist)
+        tagtypes = {}
+
+        tagsmod.findglobaltags(self.ui, self, alltags, tagtypes)
+        tagsmod.readlocaltags(self.ui, self, alltags, tagtypes)
+
+        # Build the return dicts.  Have to re-encode tag names because
+        # the tags module always uses UTF-8 (in order not to lose info
+        # writing to the cache), but the rest of Mercurial wants them in
+        # local encoding.
+        tags = {}
+        for (name, (node, hist)) in alltags.iteritems():
+            if node != nullid:
+                tags[encoding.tolocal(name)] = node
+        tags['tip'] = self.changelog.tip()
+        tagtypes = dict([(encoding.tolocal(name), value)
+                         for (name, value) in tagtypes.iteritems()])
+        return (tags, tagtypes)
+
+    def tagtype(self, tagname):
+        '''
+        return the type of the given tag. result can be:
+
+        'local'  : a local tag
+        'global' : a global tag
+        None     : tag does not exist
+        '''
+
+        self.tags()
+
+        return self._tagtypes.get(tagname)
+
+    def tagslist(self):
+        '''return a list of tags ordered by revision'''
+        l = []
+        for t, n in self.tags().iteritems():
+            try:
+                r = self.changelog.rev(n)
+            except:
+                r = -2 # sort to the beginning of the list if unknown
+            l.append((r, t, n))
+        return [(t, n) for r, t, n in sorted(l)]
+
+    def nodetags(self, node):
+        '''return the tags associated with a node'''
+        if not self.nodetagscache:
+            self.nodetagscache = {}
+            for t, n in self.tags().iteritems():
+                self.nodetagscache.setdefault(n, []).append(t)
+            for tags in self.nodetagscache.itervalues():
+                tags.sort()
+        return self.nodetagscache.get(node, [])
+
+    def _branchtags(self, partial, lrev):
+        # TODO: rename this function?
+        tiprev = len(self) - 1
+        if lrev != tiprev:
+            ctxgen = (self[r] for r in xrange(lrev + 1, tiprev + 1))
+            self._updatebranchcache(partial, ctxgen)
+            self._writebranchcache(partial, self.changelog.tip(), tiprev)
+
+        return partial
+
+    def updatebranchcache(self):
+        tip = self.changelog.tip()
+        if self._branchcache is not None and self._branchcachetip == tip:
+            return self._branchcache
+
+        oldtip = self._branchcachetip
+        self._branchcachetip = tip
+        if oldtip is None or oldtip not in self.changelog.nodemap:
+            partial, last, lrev = self._readbranchcache()
+        else:
+            lrev = self.changelog.rev(oldtip)
+            partial = self._branchcache
+
+        self._branchtags(partial, lrev)
+        # this private cache holds all heads (not just tips)
+        self._branchcache = partial
+
+    def branchmap(self):
+        '''returns a dictionary {branch: [branchheads]}'''
+        self.updatebranchcache()
+        return self._branchcache
+
+    def branchtags(self):
+        '''return a dict where branch names map to the tipmost head of
+        the branch, open heads come before closed'''
+        bt = {}
+        for bn, heads in self.branchmap().iteritems():
+            tip = heads[-1]
+            for h in reversed(heads):
+                if 'close' not in self.changelog.read(h)[5]:
+                    tip = h
+                    break
+            bt[bn] = tip
+        return bt
+
+
+    def _readbranchcache(self):
+        partial = {}
+        try:
+            f = self.opener("branchheads.cache")
+            lines = f.read().split('\n')
+            f.close()
+        except (IOError, OSError):
+            return {}, nullid, nullrev
+
+        try:
+            last, lrev = lines.pop(0).split(" ", 1)
+            last, lrev = bin(last), int(lrev)
+            if lrev >= len(self) or self[lrev].node() != last:
+                # invalidate the cache
+                raise ValueError('invalidating branch cache (tip differs)')
+            for l in lines:
+                if not l:
+                    continue
+                node, label = l.split(" ", 1)
+                partial.setdefault(label.strip(), []).append(bin(node))
+        except KeyboardInterrupt:
+            raise
+        except Exception, inst:
+            if self.ui.debugflag:
+                self.ui.warn(str(inst), '\n')
+            partial, last, lrev = {}, nullid, nullrev
+        return partial, last, lrev
+
+    def _writebranchcache(self, branches, tip, tiprev):
+        try:
+            f = self.opener("branchheads.cache", "w", atomictemp=True)
+            f.write("%s %s\n" % (hex(tip), tiprev))
+            for label, nodes in branches.iteritems():
+                for node in nodes:
+                    f.write("%s %s\n" % (hex(node), label))
+            f.rename()
+        except (IOError, OSError):
+            pass
+
+    def _updatebranchcache(self, partial, ctxgen):
+        # collect new branch entries
+        newbranches = {}
+        for c in ctxgen:
+            newbranches.setdefault(c.branch(), []).append(c.node())
+        # if older branchheads are reachable from new ones, they aren't
+        # really branchheads. Note checking parents is insufficient:
+        # 1 (branch a) -> 2 (branch b) -> 3 (branch a)
+        for branch, newnodes in newbranches.iteritems():
+            bheads = partial.setdefault(branch, [])
+            bheads.extend(newnodes)
+            if len(bheads) <= 1:
+                continue
+            # starting from tip means fewer passes over reachable
+            while newnodes:
+                latest = newnodes.pop()
+                if latest not in bheads:
+                    continue
+                minbhrev = self[min([self[bh].rev() for bh in bheads])].node()
+                reachable = self.changelog.reachable(latest, minbhrev)
+                reachable.remove(latest)
+                bheads = [b for b in bheads if b not in reachable]
+            partial[branch] = bheads
+
+    def lookup(self, key):
+        if isinstance(key, int):
+            return self.changelog.node(key)
+        elif key == '.':
+            return self.dirstate.parents()[0]
+        elif key == 'null':
+            return nullid
+        elif key == 'tip':
+            return self.changelog.tip()
+        n = self.changelog._match(key)
+        if n:
+            return n
+        if key in self.tags():
+            return self.tags()[key]
+        if key in self.branchtags():
+            return self.branchtags()[key]
+        n = self.changelog._partialmatch(key)
+        if n:
+            return n
+
+        # can't find key, check if it might have come from damaged dirstate
+        if key in self.dirstate.parents():
+            raise error.Abort(_("working directory has unknown parent '%s'!")
+                              % short(key))
+        try:
+            if len(key) == 20:
+                key = hex(key)
+        except:
+            pass
+        raise error.RepoLookupError(_("unknown revision '%s'") % key)
+
+    def lookupbranch(self, key, remote=None):
+        repo = remote or self
+        if key in repo.branchmap():
+            return key
+
+        repo = (remote and remote.local()) and remote or self
+        return repo[key].branch()
+
+    def local(self):
+        return True
+
+    def join(self, f):
+        return os.path.join(self.path, f)
+
+    def wjoin(self, f):
+        return os.path.join(self.root, f)
+
+    def file(self, f):
+        if f[0] == '/':
+            f = f[1:]
+        return filelog.filelog(self.sopener, f)
+
+    def changectx(self, changeid):
+        return self[changeid]
+
+    def parents(self, changeid=None):
+        '''get list of changectxs for parents of changeid'''
+        return self[changeid].parents()
+
+    def filectx(self, path, changeid=None, fileid=None):
+        """changeid can be a changeset revision, node, or tag.
+           fileid can be a file revision or node."""
+        return context.filectx(self, path, changeid, fileid)
+
+    def getcwd(self):
+        return self.dirstate.getcwd()
+
+    def pathto(self, f, cwd=None):
+        return self.dirstate.pathto(f, cwd)
+
+    def wfile(self, f, mode='r'):
+        return self.wopener(f, mode)
+
+    def _link(self, f):
+        return os.path.islink(self.wjoin(f))
+
+    def _loadfilter(self, filter):
+        if filter not in self.filterpats:
+            l = []
+            for pat, cmd in self.ui.configitems(filter):
+                if cmd == '!':
+                    continue
+                mf = matchmod.match(self.root, '', [pat])
+                fn = None
+                params = cmd
+                for name, filterfn in self._datafilters.iteritems():
+                    if cmd.startswith(name):
+                        fn = filterfn
+                        params = cmd[len(name):].lstrip()
+                        break
+                if not fn:
+                    fn = lambda s, c, **kwargs: util.filter(s, c)
+                # Wrap old filters not supporting keyword arguments
+                if not inspect.getargspec(fn)[2]:
+                    oldfn = fn
+                    fn = lambda s, c, **kwargs: oldfn(s, c)
+                l.append((mf, fn, params))
+            self.filterpats[filter] = l
+        return self.filterpats[filter]
+
+    def _filter(self, filterpats, filename, data):
+        for mf, fn, cmd in filterpats:
+            if mf(filename):
+                self.ui.debug("filtering %s through %s\n" % (filename, cmd))
+                data = fn(data, cmd, ui=self.ui, repo=self, filename=filename)
+                break
+
+        return data
+
+    @propertycache
+    def _encodefilterpats(self):
+        return self._loadfilter('encode')
+
+    @propertycache
+    def _decodefilterpats(self):
+        return self._loadfilter('decode')
+
+    def adddatafilter(self, name, filter):
+        self._datafilters[name] = filter
+
+    def wread(self, filename):
+        if self._link(filename):
+            data = os.readlink(self.wjoin(filename))
+        else:
+            data = self.wopener(filename, 'r').read()
+        return self._filter(self._encodefilterpats, filename, data)
+
+    def wwrite(self, filename, data, flags):
+        data = self._filter(self._decodefilterpats, filename, data)
+        try:
+            os.unlink(self.wjoin(filename))
+        except OSError:
+            pass
+        if 'l' in flags:
+            self.wopener.symlink(data, filename)
+        else:
+            self.wopener(filename, 'w').write(data)
+            if 'x' in flags:
+                util.set_flags(self.wjoin(filename), False, True)
+
+    def wwritedata(self, filename, data):
+        return self._filter(self._decodefilterpats, filename, data)
+
+    def transaction(self, desc):
+        tr = self._transref and self._transref() or None
+        if tr and tr.running():
+            return tr.nest()
+
+        # abort here if the journal already exists
+        if os.path.exists(self.sjoin("journal")):
+            raise error.RepoError(
+                _("abandoned transaction found - run hg recover"))
+
+        # save dirstate for rollback
+        try:
+            ds = self.opener("dirstate").read()
+        except IOError:
+            ds = ""
+        self.opener("journal.dirstate", "w").write(ds)
+        self.opener("journal.branch", "w").write(self.dirstate.branch())
+        self.opener("journal.desc", "w").write("%d\n%s\n" % (len(self), desc))
+
+        renames = [(self.sjoin("journal"), self.sjoin("undo")),
+                   (self.join("journal.dirstate"), self.join("undo.dirstate")),
+                   (self.join("journal.branch"), self.join("undo.branch")),
+                   (self.join("journal.desc"), self.join("undo.desc"))]
+        tr = transaction.transaction(self.ui.warn, self.sopener,
+                                     self.sjoin("journal"),
+                                     aftertrans(renames),
+                                     self.store.createmode)
+        self._transref = weakref.ref(tr)
+        return tr
+
+    def recover(self):
+        lock = self.lock()
+        try:
+            if os.path.exists(self.sjoin("journal")):
+                self.ui.status(_("rolling back interrupted transaction\n"))
+                transaction.rollback(self.sopener, self.sjoin("journal"),
+                                     self.ui.warn)
+                self.invalidate()
+                return True
+            else:
+                self.ui.warn(_("no interrupted transaction available\n"))
+                return False
+        finally:
+            lock.release()
+
+    def rollback(self, dryrun=False):
+        wlock = lock = None
+        try:
+            wlock = self.wlock()
+            lock = self.lock()
+            if os.path.exists(self.sjoin("undo")):
+                try:
+                    args = self.opener("undo.desc", "r").read().splitlines()
+                    if len(args) >= 3 and self.ui.verbose:
+                        desc = _("rolling back to revision %s"
+                                 " (undo %s: %s)\n") % (
+                                 int(args[0]) - 1, args[1], args[2])
+                    elif len(args) >= 2:
+                        desc = _("rolling back to revision %s (undo %s)\n") % (
+                                 int(args[0]) - 1, args[1])
+                except IOError:
+                    desc = _("rolling back unknown transaction\n")
+                self.ui.status(desc)
+                if dryrun:
+                    return
+                transaction.rollback(self.sopener, self.sjoin("undo"),
+                                     self.ui.warn)
+                util.rename(self.join("undo.dirstate"), self.join("dirstate"))
+                try:
+                    branch = self.opener("undo.branch").read()
+                    self.dirstate.setbranch(branch)
+                except IOError:
+                    self.ui.warn(_("Named branch could not be reset, "
+                                   "current branch still is: %s\n")
+                                 % encoding.tolocal(self.dirstate.branch()))
+                self.invalidate()
+                self.dirstate.invalidate()
+                self.destroyed()
+            else:
+                self.ui.warn(_("no rollback information available\n"))
+                return 1
+        finally:
+            release(lock, wlock)
+
+    def invalidatecaches(self):
+        self._tags = None
+        self._tagtypes = None
+        self.nodetagscache = None
+        self._branchcache = None # in UTF-8
+        self._branchcachetip = None
+
+    def invalidate(self):
+        for a in "changelog manifest".split():
+            if a in self.__dict__:
+                delattr(self, a)
+        self.invalidatecaches()
+
+    def _lock(self, lockname, wait, releasefn, acquirefn, desc):
+        try:
+            l = lock.lock(lockname, 0, releasefn, desc=desc)
+        except error.LockHeld, inst:
+            if not wait:
+                raise
+            self.ui.warn(_("waiting for lock on %s held by %r\n") %
+                         (desc, inst.locker))
+            # default to 600 seconds timeout
+            l = lock.lock(lockname, int(self.ui.config("ui", "timeout", "600")),
+                          releasefn, desc=desc)
+        if acquirefn:
+            acquirefn()
+        return l
+
+    def lock(self, wait=True):
+        '''Lock the repository store (.hg/store) and return a weak reference
+        to the lock. Use this before modifying the store (e.g. committing or
+        stripping). If you are opening a transaction, get a lock as well.)'''
+        l = self._lockref and self._lockref()
+        if l is not None and l.held:
+            l.lock()
+            return l
+
+        l = self._lock(self.sjoin("lock"), wait, None, self.invalidate,
+                       _('repository %s') % self.origroot)
+        self._lockref = weakref.ref(l)
+        return l
+
+    def wlock(self, wait=True):
+        '''Lock the non-store parts of the repository (everything under
+        .hg except .hg/store) and return a weak reference to the lock.
+        Use this before modifying files in .hg.'''
+        l = self._wlockref and self._wlockref()
+        if l is not None and l.held:
+            l.lock()
+            return l
+
+        l = self._lock(self.join("wlock"), wait, self.dirstate.write,
+                       self.dirstate.invalidate, _('working directory of %s') %
+                       self.origroot)
+        self._wlockref = weakref.ref(l)
+        return l
+
+    def _filecommit(self, fctx, manifest1, manifest2, linkrev, tr, changelist):
+        """
+        commit an individual file as part of a larger transaction
+        """
+
+        fname = fctx.path()
+        text = fctx.data()
+        flog = self.file(fname)
+        fparent1 = manifest1.get(fname, nullid)
+        fparent2 = fparent2o = manifest2.get(fname, nullid)
+
+        meta = {}
+        copy = fctx.renamed()
+        if copy and copy[0] != fname:
+            # Mark the new revision of this file as a copy of another
+            # file.  This copy data will effectively act as a parent
+            # of this new revision.  If this is a merge, the first
+            # parent will be the nullid (meaning "look up the copy data")
+            # and the second one will be the other parent.  For example:
+            #
+            # 0 --- 1 --- 3   rev1 changes file foo
+            #   \       /     rev2 renames foo to bar and changes it
+            #    \- 2 -/      rev3 should have bar with all changes and
+            #                      should record that bar descends from
+            #                      bar in rev2 and foo in rev1
+            #
+            # this allows this merge to succeed:
+            #
+            # 0 --- 1 --- 3   rev4 reverts the content change from rev2
+            #   \       /     merging rev3 and rev4 should use bar@rev2
+            #    \- 2 --- 4        as the merge base
+            #
+
+            cfname = copy[0]
+            crev = manifest1.get(cfname)
+            newfparent = fparent2
+
+            if manifest2: # branch merge
+                if fparent2 == nullid or crev is None: # copied on remote side
+                    if cfname in manifest2:
+                        crev = manifest2[cfname]
+                        newfparent = fparent1
+
+            # find source in nearest ancestor if we've lost track
+            if not crev:
+                self.ui.debug(" %s: searching for copy revision for %s\n" %
+                              (fname, cfname))
+                for ancestor in self[None].ancestors():
+                    if cfname in ancestor:
+                        crev = ancestor[cfname].filenode()
+                        break
+
+            if crev:
+                self.ui.debug(" %s: copy %s:%s\n" % (fname, cfname, hex(crev)))
+                meta["copy"] = cfname
+                meta["copyrev"] = hex(crev)
+                fparent1, fparent2 = nullid, newfparent
+            else:
+                self.ui.warn(_("warning: can't find ancestor for '%s' "
+                               "copied from '%s'!\n") % (fname, cfname))
+
+        elif fparent2 != nullid:
+            # is one parent an ancestor of the other?
+            fparentancestor = flog.ancestor(fparent1, fparent2)
+            if fparentancestor == fparent1:
+                fparent1, fparent2 = fparent2, nullid
+            elif fparentancestor == fparent2:
+                fparent2 = nullid
+
+        # is the file changed?
+        if fparent2 != nullid or flog.cmp(fparent1, text) or meta:
+            changelist.append(fname)
+            return flog.add(text, meta, tr, linkrev, fparent1, fparent2)
+
+        # are just the flags changed during merge?
+        if fparent1 != fparent2o and manifest1.flags(fname) != fctx.flags():
+            changelist.append(fname)
+
+        return fparent1
+
+    def commit(self, text="", user=None, date=None, match=None, force=False,
+               editor=False, extra={}):
+        """Add a new revision to current repository.
+
+        Revision information is gathered from the working directory,
+        match can be used to filter the committed files. If editor is
+        supplied, it is called to get a commit message.
+        """
+
+        def fail(f, msg):
+            raise util.Abort('%s: %s' % (f, msg))
+
+        if not match:
+            match = matchmod.always(self.root, '')
+
+        if not force:
+            vdirs = []
+            match.dir = vdirs.append
+            match.bad = fail
+
+        wlock = self.wlock()
+        try:
+            wctx = self[None]
+            merge = len(wctx.parents()) > 1
+
+            if (not force and merge and match and
+                (match.files() or match.anypats())):
+                raise util.Abort(_('cannot partially commit a merge '
+                                   '(do not specify files or patterns)'))
+
+            changes = self.status(match=match, clean=force)
+            if force:
+                changes[0].extend(changes[6]) # mq may commit unchanged files
+
+            # check subrepos
+            subs = []
+            removedsubs = set()
+            for p in wctx.parents():
+                removedsubs.update(s for s in p.substate if match(s))
+            for s in wctx.substate:
+                removedsubs.discard(s)
+                if match(s) and wctx.sub(s).dirty():
+                    subs.append(s)
+            if (subs or removedsubs):
+                if (not match('.hgsub') and
+                    '.hgsub' in (wctx.modified() + wctx.added())):
+                    raise util.Abort(_("can't commit subrepos without .hgsub"))
+                if '.hgsubstate' not in changes[0]:
+                    changes[0].insert(0, '.hgsubstate')
+
+            # make sure all explicit patterns are matched
+            if not force and match.files():
+                matched = set(changes[0] + changes[1] + changes[2])
+
+                for f in match.files():
+                    if f == '.' or f in matched or f in wctx.substate:
+                        continue
+                    if f in changes[3]: # missing
+                        fail(f, _('file not found!'))
+                    if f in vdirs: # visited directory
+                        d = f + '/'
+                        for mf in matched:
+                            if mf.startswith(d):
+                                break
+                        else:
+                            fail(f, _("no match under directory!"))
+                    elif f not in self.dirstate:
+                        fail(f, _("file not tracked!"))
+
+            if (not force and not extra.get("close") and not merge
+                and not (changes[0] or changes[1] or changes[2])
+                and wctx.branch() == wctx.p1().branch()):
+                return None
+
+            ms = mergemod.mergestate(self)
+            for f in changes[0]:
+                if f in ms and ms[f] == 'u':
+                    raise util.Abort(_("unresolved merge conflicts "
+                                                    "(see hg resolve)"))
+
+            cctx = context.workingctx(self, text, user, date, extra, changes)
+            if editor:
+                cctx._text = editor(self, cctx, subs)
+            edited = (text != cctx._text)
+
+            # commit subs
+            if subs or removedsubs:
+                state = wctx.substate.copy()
+                for s in sorted(subs):
+                    sub = wctx.sub(s)
+                    self.ui.status(_('committing subrepository %s\n') %
+                        subrepo.subrelpath(sub))
+                    sr = sub.commit(cctx._text, user, date)
+                    state[s] = (state[s][0], sr)
+                subrepo.writestate(self, state)
+
+            # Save commit message in case this transaction gets rolled back
+            # (e.g. by a pretxncommit hook).  Leave the content alone on
+            # the assumption that the user will use the same editor again.
+            msgfile = self.opener('last-message.txt', 'wb')
+            msgfile.write(cctx._text)
+            msgfile.close()
+
+            p1, p2 = self.dirstate.parents()
+            hookp1, hookp2 = hex(p1), (p2 != nullid and hex(p2) or '')
+            try:
+                self.hook("precommit", throw=True, parent1=hookp1, parent2=hookp2)
+                ret = self.commitctx(cctx, True)
+            except:
+                if edited:
+                    msgfn = self.pathto(msgfile.name[len(self.root)+1:])
+                    self.ui.write(
+                        _('note: commit message saved in %s\n') % msgfn)
+                raise
+
+            # update dirstate and mergestate
+            for f in changes[0] + changes[1]:
+                self.dirstate.normal(f)
+            for f in changes[2]:
+                self.dirstate.forget(f)
+            self.dirstate.setparents(ret)
+            ms.reset()
+        finally:
+            wlock.release()
+
+        self.hook("commit", node=hex(ret), parent1=hookp1, parent2=hookp2)
+        return ret
+
+    def commitctx(self, ctx, error=False):
+        """Add a new revision to current repository.
+        Revision information is passed via the context argument.
+        """
+
+        tr = lock = None
+        removed = list(ctx.removed())
+        p1, p2 = ctx.p1(), ctx.p2()
+        m1 = p1.manifest().copy()
+        m2 = p2.manifest()
+        user = ctx.user()
+
+        lock = self.lock()
+        try:
+            tr = self.transaction("commit")
+            trp = weakref.proxy(tr)
+
+            # check in files
+            new = {}
+            changed = []
+            linkrev = len(self)
+            for f in sorted(ctx.modified() + ctx.added()):
+                self.ui.note(f + "\n")
+                try:
+                    fctx = ctx[f]
+                    new[f] = self._filecommit(fctx, m1, m2, linkrev, trp,
+                                              changed)
+                    m1.set(f, fctx.flags())
+                except OSError, inst:
+                    self.ui.warn(_("trouble committing %s!\n") % f)
+                    raise
+                except IOError, inst:
+                    errcode = getattr(inst, 'errno', errno.ENOENT)
+                    if error or errcode and errcode != errno.ENOENT:
+                        self.ui.warn(_("trouble committing %s!\n") % f)
+                        raise
+                    else:
+                        removed.append(f)
+
+            # update manifest
+            m1.update(new)
+            removed = [f for f in sorted(removed) if f in m1 or f in m2]
+            drop = [f for f in removed if f in m1]
+            for f in drop:
+                del m1[f]
+            mn = self.manifest.add(m1, trp, linkrev, p1.manifestnode(),
+                                   p2.manifestnode(), (new, drop))
+
+            # update changelog
+            self.changelog.delayupdate()
+            n = self.changelog.add(mn, changed + removed, ctx.description(),
+                                   trp, p1.node(), p2.node(),
+                                   user, ctx.date(), ctx.extra().copy())
+            p = lambda: self.changelog.writepending() and self.root or ""
+            xp1, xp2 = p1.hex(), p2 and p2.hex() or ''
+            self.hook('pretxncommit', throw=True, node=hex(n), parent1=xp1,
+                      parent2=xp2, pending=p)
+            self.changelog.finalize(trp)
+            tr.close()
+
+            if self._branchcache:
+                self.updatebranchcache()
+            return n
+        finally:
+            if tr:
+                tr.release()
+            lock.release()
+
+    def destroyed(self):
+        '''Inform the repository that nodes have been destroyed.
+        Intended for use by strip and rollback, so there's a common
+        place for anything that has to be done after destroying history.'''
+        # XXX it might be nice if we could take the list of destroyed
+        # nodes, but I don't see an easy way for rollback() to do that
+
+        # Ensure the persistent tag cache is updated.  Doing it now
+        # means that the tag cache only has to worry about destroyed
+        # heads immediately after a strip/rollback.  That in turn
+        # guarantees that "cachetip == currenttip" (comparing both rev
+        # and node) always means no nodes have been added or destroyed.
+
+        # XXX this is suboptimal when qrefresh'ing: we strip the current
+        # head, refresh the tag cache, then immediately add a new head.
+        # But I think doing it this way is necessary for the "instant
+        # tag cache retrieval" case to work.
+        self.invalidatecaches()
+
+    def walk(self, match, node=None):
+        '''
+        walk recursively through the directory tree or a given
+        changeset, finding all files matched by the match
+        function
+        '''
+        return self[node].walk(match)
+
+    def status(self, node1='.', node2=None, match=None,
+               ignored=False, clean=False, unknown=False,
+               listsubrepos=False):
+        """return status of files between two nodes or node and working directory
+
+        If node1 is None, use the first dirstate parent instead.
+        If node2 is None, compare node1 with working directory.
+        """
+
+        def mfmatches(ctx):
+            mf = ctx.manifest().copy()
+            for fn in mf.keys():
+                if not match(fn):
+                    del mf[fn]
+            return mf
+
+        if isinstance(node1, context.changectx):
+            ctx1 = node1
+        else:
+            ctx1 = self[node1]
+        if isinstance(node2, context.changectx):
+            ctx2 = node2
+        else:
+            ctx2 = self[node2]
+
+        working = ctx2.rev() is None
+        parentworking = working and ctx1 == self['.']
+        match = match or matchmod.always(self.root, self.getcwd())
+        listignored, listclean, listunknown = ignored, clean, unknown
+
+        # load earliest manifest first for caching reasons
+        if not working and ctx2.rev() < ctx1.rev():
+            ctx2.manifest()
+
+        if not parentworking:
+            def bad(f, msg):
+                if f not in ctx1:
+                    self.ui.warn('%s: %s\n' % (self.dirstate.pathto(f), msg))
+            match.bad = bad
+
+        if working: # we need to scan the working dir
+            subrepos = []
+            if '.hgsub' in self.dirstate:
+                subrepos = ctx1.substate.keys()
+            s = self.dirstate.status(match, subrepos, listignored,
+                                     listclean, listunknown)
+            cmp, modified, added, removed, deleted, unknown, ignored, clean = s
+
+            # check for any possibly clean files
+            if parentworking and cmp:
+                fixup = []
+                # do a full compare of any files that might have changed
+                for f in sorted(cmp):
+                    if (f not in ctx1 or ctx2.flags(f) != ctx1.flags(f)
+                        or ctx1[f].cmp(ctx2[f])):
+                        modified.append(f)
+                    else:
+                        fixup.append(f)
+
+                # update dirstate for files that are actually clean
+                if fixup:
+                    if listclean:
+                        clean += fixup
+
+                    try:
+                        # updating the dirstate is optional
+                        # so we don't wait on the lock
+                        wlock = self.wlock(False)
+                        try:
+                            for f in fixup:
+                                self.dirstate.normal(f)
+                        finally:
+                            wlock.release()
+                    except error.LockError:
+                        pass
+
+        if not parentworking:
+            mf1 = mfmatches(ctx1)
+            if working:
+                # we are comparing working dir against non-parent
+                # generate a pseudo-manifest for the working dir
+                mf2 = mfmatches(self['.'])
+                for f in cmp + modified + added:
+                    mf2[f] = None
+                    mf2.set(f, ctx2.flags(f))
+                for f in removed:
+                    if f in mf2:
+                        del mf2[f]
+            else:
+                # we are comparing two revisions
+                deleted, unknown, ignored = [], [], []
+                mf2 = mfmatches(ctx2)
+
+            modified, added, clean = [], [], []
+            for fn in mf2:
+                if fn in mf1:
+                    if (mf1.flags(fn) != mf2.flags(fn) or
+                        (mf1[fn] != mf2[fn] and
+                         (mf2[fn] or ctx1[fn].cmp(ctx2[fn])))):
+                        modified.append(fn)
+                    elif listclean:
+                        clean.append(fn)
+                    del mf1[fn]
+                else:
+                    added.append(fn)
+            removed = mf1.keys()
+
+        r = modified, added, removed, deleted, unknown, ignored, clean
+
+        if listsubrepos:
+            for subpath, sub in subrepo.itersubrepos(ctx1, ctx2):
+                if working:
+                    rev2 = None
+                else:
+                    rev2 = ctx2.substate[subpath][1]
+                try:
+                    submatch = matchmod.narrowmatcher(subpath, match)
+                    s = sub.status(rev2, match=submatch, ignored=listignored,
+                                   clean=listclean, unknown=listunknown,
+                                   listsubrepos=True)
+                    for rfiles, sfiles in zip(r, s):
+                        rfiles.extend("%s/%s" % (subpath, f) for f in sfiles)
+                except error.LookupError:
+                    self.ui.status(_("skipping missing subrepository: %s\n")
+                                   % subpath)
+
+        [l.sort() for l in r]
+        return r
+
+    def heads(self, start=None):
+        heads = self.changelog.heads(start)
+        # sort the output in rev descending order
+        heads = [(-self.changelog.rev(h), h) for h in heads]
+        return [n for (r, n) in sorted(heads)]
+
+    def branchheads(self, branch=None, start=None, closed=False):
+        '''return a (possibly filtered) list of heads for the given branch
+
+        Heads are returned in topological order, from newest to oldest.
+        If branch is None, use the dirstate branch.
+        If start is not None, return only heads reachable from start.
+        If closed is True, return heads that are marked as closed as well.
+        '''
+        if branch is None:
+            branch = self[None].branch()
+        branches = self.branchmap()
+        if branch not in branches:
+            return []
+        # the cache returns heads ordered lowest to highest
+        bheads = list(reversed(branches[branch]))
+        if start is not None:
+            # filter out the heads that cannot be reached from startrev
+            fbheads = set(self.changelog.nodesbetween([start], bheads)[2])
+            bheads = [h for h in bheads if h in fbheads]
+        if not closed:
+            bheads = [h for h in bheads if
+                      ('close' not in self.changelog.read(h)[5])]
+        return bheads
+
+    def branches(self, nodes):
+        if not nodes:
+            nodes = [self.changelog.tip()]
+        b = []
+        for n in nodes:
+            t = n
+            while 1:
+                p = self.changelog.parents(n)
+                if p[1] != nullid or p[0] == nullid:
+                    b.append((t, n, p[0], p[1]))
+                    break
+                n = p[0]
+        return b
+
+    def between(self, pairs):
+        r = []
+
+        for top, bottom in pairs:
+            n, l, i = top, [], 0
+            f = 1
+
+            while n != bottom and n != nullid:
+                p = self.changelog.parents(n)[0]
+                if i == f:
+                    l.append(n)
+                    f = f * 2
+                n = p
+                i += 1
+
+            r.append(l)
+
+        return r
+
+    def pull(self, remote, heads=None, force=False):
+        lock = self.lock()
+        try:
+            tmp = discovery.findcommonincoming(self, remote, heads=heads,
+                                               force=force)
+            common, fetch, rheads = tmp
+            if not fetch:
+                self.ui.status(_("no changes found\n"))
+                return 0
+
+            if heads is None and fetch == [nullid]:
+                self.ui.status(_("requesting all changes\n"))
+            elif heads is None and remote.capable('changegroupsubset'):
+                # issue1320, avoid a race if remote changed after discovery
+                heads = rheads
+
+            if heads is None:
+                cg = remote.changegroup(fetch, 'pull')
+            else:
+                if not remote.capable('changegroupsubset'):
+                    raise util.Abort(_("partial pull cannot be done because "
+                                       "other repository doesn't support "
+                                       "changegroupsubset."))
+                cg = remote.changegroupsubset(fetch, heads, 'pull')
+            return self.addchangegroup(cg, 'pull', remote.url(), lock=lock)
+        finally:
+            lock.release()
+
+    def push(self, remote, force=False, revs=None, newbranch=False):
+        '''Push outgoing changesets (limited by revs) from the current
+        repository to remote. Return an integer:
+          - 0 means HTTP error *or* nothing to push
+          - 1 means we pushed and remote head count is unchanged *or*
+            we have outgoing changesets but refused to push
+          - other values as described by addchangegroup()
+        '''
+        # there are two ways to push to remote repo:
+        #
+        # addchangegroup assumes local user can lock remote
+        # repo (local filesystem, old ssh servers).
+        #
+        # unbundle assumes local user cannot lock remote repo (new ssh
+        # servers, http servers).
+
+        lock = None
+        unbundle = remote.capable('unbundle')
+        if not unbundle:
+            lock = remote.lock()
+        try:
+            ret = discovery.prepush(self, remote, force, revs, newbranch)
+            if ret[0] is None:
+                # and here we return 0 for "nothing to push" or 1 for
+                # "something to push but I refuse"
+                return ret[1]
+
+            cg, remote_heads = ret
+            if unbundle:
+                # local repo finds heads on server, finds out what revs it must
+                # push.  once revs transferred, if server finds it has
+                # different heads (someone else won commit/push race), server
+                # aborts.
+                if force:
+                    remote_heads = ['force']
+                # ssh: return remote's addchangegroup()
+                # http: return remote's addchangegroup() or 0 for error
+                return remote.unbundle(cg, remote_heads, 'push')
+            else:
+                # we return an integer indicating remote head count change
+                return remote.addchangegroup(cg, 'push', self.url(), lock=lock)
+        finally:
+            if lock is not None:
+                lock.release()
+
+    def changegroupinfo(self, nodes, source):
+        if self.ui.verbose or source == 'bundle':
+            self.ui.status(_("%d changesets found\n") % len(nodes))
+        if self.ui.debugflag:
+            self.ui.debug("list of changesets:\n")
+            for node in nodes:
+                self.ui.debug("%s\n" % hex(node))
+
+    def changegroupsubset(self, bases, heads, source, extranodes=None):
+        """Compute a changegroup consisting of all the nodes that are
+        descendents of any of the bases and ancestors of any of the heads.
+        Return a chunkbuffer object whose read() method will return
+        successive changegroup chunks.
+
+        It is fairly complex as determining which filenodes and which
+        manifest nodes need to be included for the changeset to be complete
+        is non-trivial.
+
+        Another wrinkle is doing the reverse, figuring out which changeset in
+        the changegroup a particular filenode or manifestnode belongs to.
+
+        The caller can specify some nodes that must be included in the
+        changegroup using the extranodes argument.  It should be a dict
+        where the keys are the filenames (or 1 for the manifest), and the
+        values are lists of (node, linknode) tuples, where node is a wanted
+        node and linknode is the changelog node that should be transmitted as
+        the linkrev.
+        """
+
+        # Set up some initial variables
+        # Make it easy to refer to self.changelog
+        cl = self.changelog
+        # Compute the list of changesets in this changegroup.
+        # Some bases may turn out to be superfluous, and some heads may be
+        # too.  nodesbetween will return the minimal set of bases and heads
+        # necessary to re-create the changegroup.
+        if not bases:
+            bases = [nullid]
+        msng_cl_lst, bases, heads = cl.nodesbetween(bases, heads)
+
+        if extranodes is None:
+            # can we go through the fast path ?
+            heads.sort()
+            allheads = self.heads()
+            allheads.sort()
+            if heads == allheads:
+                return self._changegroup(msng_cl_lst, source)
+
+        # slow path
+        self.hook('preoutgoing', throw=True, source=source)
+
+        self.changegroupinfo(msng_cl_lst, source)
+
+        # We assume that all ancestors of bases are known
+        commonrevs = set(cl.ancestors(*[cl.rev(n) for n in bases]))
+
+        # Make it easy to refer to self.manifest
+        mnfst = self.manifest
+        # We don't know which manifests are missing yet
+        msng_mnfst_set = {}
+        # Nor do we know which filenodes are missing.
+        msng_filenode_set = {}
+
+        junk = mnfst.index[len(mnfst) - 1] # Get around a bug in lazyindex
+        junk = None
+
+        # A changeset always belongs to itself, so the changenode lookup
+        # function for a changenode is identity.
+        def identity(x):
+            return x
+
+        # A function generating function that sets up the initial environment
+        # the inner function.
+        def filenode_collector(changedfiles):
+            # This gathers information from each manifestnode included in the
+            # changegroup about which filenodes the manifest node references
+            # so we can include those in the changegroup too.
+            #
+            # It also remembers which changenode each filenode belongs to.  It
+            # does this by assuming the a filenode belongs to the changenode
+            # the first manifest that references it belongs to.
+            def collect_msng_filenodes(mnfstnode):
+                r = mnfst.rev(mnfstnode)
+                if mnfst.deltaparent(r) in mnfst.parentrevs(r):
+                    # If the previous rev is one of the parents,
+                    # we only need to see a diff.
+                    deltamf = mnfst.readdelta(mnfstnode)
+                    # For each line in the delta
+                    for f, fnode in deltamf.iteritems():
+                        # And if the file is in the list of files we care
+                        # about.
+                        if f in changedfiles:
+                            # Get the changenode this manifest belongs to
+                            clnode = msng_mnfst_set[mnfstnode]
+                            # Create the set of filenodes for the file if
+                            # there isn't one already.
+                            ndset = msng_filenode_set.setdefault(f, {})
+                            # And set the filenode's changelog node to the
+                            # manifest's if it hasn't been set already.
+                            ndset.setdefault(fnode, clnode)
+                else:
+                    # Otherwise we need a full manifest.
+                    m = mnfst.read(mnfstnode)
+                    # For every file in we care about.
+                    for f in changedfiles:
+                        fnode = m.get(f, None)
+                        # If it's in the manifest
+                        if fnode is not None:
+                            # See comments above.
+                            clnode = msng_mnfst_set[mnfstnode]
+                            ndset = msng_filenode_set.setdefault(f, {})
+                            ndset.setdefault(fnode, clnode)
+            return collect_msng_filenodes
+
+        # If we determine that a particular file or manifest node must be a
+        # node that the recipient of the changegroup will already have, we can
+        # also assume the recipient will have all the parents.  This function
+        # prunes them from the set of missing nodes.
+        def prune(revlog, missingnodes):
+            hasset = set()
+            # If a 'missing' filenode thinks it belongs to a changenode we
+            # assume the recipient must have, then the recipient must have
+            # that filenode.
+            for n in missingnodes:
+                clrev = revlog.linkrev(revlog.rev(n))
+                if clrev in commonrevs:
+                    hasset.add(n)
+            for n in hasset:
+                missingnodes.pop(n, None)
+            for r in revlog.ancestors(*[revlog.rev(n) for n in hasset]):
+                missingnodes.pop(revlog.node(r), None)
+
+        # Add the nodes that were explicitly requested.
+        def add_extra_nodes(name, nodes):
+            if not extranodes or name not in extranodes:
+                return
+
+            for node, linknode in extranodes[name]:
+                if node not in nodes:
+                    nodes[node] = linknode
+
+        # Now that we have all theses utility functions to help out and
+        # logically divide up the task, generate the group.
+        def gengroup():
+            # The set of changed files starts empty.
+            changedfiles = set()
+            collect = changegroup.collector(cl, msng_mnfst_set, changedfiles)
+
+            # Create a changenode group generator that will call our functions
+            # back to lookup the owning changenode and collect information.
+            group = cl.group(msng_cl_lst, identity, collect)
+            for cnt, chnk in enumerate(group):
+                yield chnk
+                self.ui.progress(_('bundling changes'), cnt, unit=_('chunks'))
+            self.ui.progress(_('bundling changes'), None)
+
+            prune(mnfst, msng_mnfst_set)
+            add_extra_nodes(1, msng_mnfst_set)
+            msng_mnfst_lst = msng_mnfst_set.keys()
+            # Sort the manifestnodes by revision number.
+            msng_mnfst_lst.sort(key=mnfst.rev)
+            # Create a generator for the manifestnodes that calls our lookup
+            # and data collection functions back.
+            group = mnfst.group(msng_mnfst_lst,
+                                lambda mnode: msng_mnfst_set[mnode],
+                                filenode_collector(changedfiles))
+            for cnt, chnk in enumerate(group):
+                yield chnk
+                self.ui.progress(_('bundling manifests'), cnt, unit=_('chunks'))
+            self.ui.progress(_('bundling manifests'), None)
+
+            # These are no longer needed, dereference and toss the memory for
+            # them.
+            msng_mnfst_lst = None
+            msng_mnfst_set.clear()
+
+            if extranodes:
+                for fname in extranodes:
+                    if isinstance(fname, int):
+                        continue
+                    msng_filenode_set.setdefault(fname, {})
+                    changedfiles.add(fname)
+            # Go through all our files in order sorted by name.
+            cnt = 0
+            for fname in sorted(changedfiles):
+                filerevlog = self.file(fname)
+                if not len(filerevlog):
+                    raise util.Abort(_("empty or missing revlog for %s") % fname)
+                # Toss out the filenodes that the recipient isn't really
+                # missing.
+                missingfnodes = msng_filenode_set.pop(fname, {})
+                prune(filerevlog, missingfnodes)
+                add_extra_nodes(fname, missingfnodes)
+                # If any filenodes are left, generate the group for them,
+                # otherwise don't bother.
+                if missingfnodes:
+                    yield changegroup.chunkheader(len(fname))
+                    yield fname
+                    # Sort the filenodes by their revision # (topological order)
+                    nodeiter = list(missingfnodes)
+                    nodeiter.sort(key=filerevlog.rev)
+                    # Create a group generator and only pass in a changenode
+                    # lookup function as we need to collect no information
+                    # from filenodes.
+                    group = filerevlog.group(nodeiter,
+                                             lambda fnode: missingfnodes[fnode])
+                    for chnk in group:
+                        self.ui.progress(
+                            _('bundling files'), cnt, item=fname, unit=_('chunks'))
+                        cnt += 1
+                        yield chnk
+            # Signal that no more groups are left.
+            yield changegroup.closechunk()
+            self.ui.progress(_('bundling files'), None)
+
+            if msng_cl_lst:
+                self.hook('outgoing', node=hex(msng_cl_lst[0]), source=source)
+
+        return changegroup.unbundle10(util.chunkbuffer(gengroup()), 'UN')
+
+    def changegroup(self, basenodes, source):
+        # to avoid a race we use changegroupsubset() (issue1320)
+        return self.changegroupsubset(basenodes, self.heads(), source)
+
+    def _changegroup(self, nodes, source):
+        """Compute the changegroup of all nodes that we have that a recipient
+        doesn't.  Return a chunkbuffer object whose read() method will return
+        successive changegroup chunks.
+
+        This is much easier than the previous function as we can assume that
+        the recipient has any changenode we aren't sending them.
+
+        nodes is the set of nodes to send"""
+
+        self.hook('preoutgoing', throw=True, source=source)
+
+        cl = self.changelog
+        revset = set([cl.rev(n) for n in nodes])
+        self.changegroupinfo(nodes, source)
+
+        def identity(x):
+            return x
+
+        def gennodelst(log):
+            for r in log:
+                if log.linkrev(r) in revset:
+                    yield log.node(r)
+
+        def lookuplinkrev_func(revlog):
+            def lookuplinkrev(n):
+                return cl.node(revlog.linkrev(revlog.rev(n)))
+            return lookuplinkrev
+
+        def gengroup():
+            '''yield a sequence of changegroup chunks (strings)'''
+            # construct a list of all changed files
+            changedfiles = set()
+            mmfs = {}
+            collect = changegroup.collector(cl, mmfs, changedfiles)
+
+            for cnt, chnk in enumerate(cl.group(nodes, identity, collect)):
+                self.ui.progress(_('bundling changes'), cnt, unit=_('chunks'))
+                yield chnk
+            self.ui.progress(_('bundling changes'), None)
+
+            mnfst = self.manifest
+            nodeiter = gennodelst(mnfst)
+            for cnt, chnk in enumerate(mnfst.group(nodeiter,
+                                                   lookuplinkrev_func(mnfst))):
+                self.ui.progress(_('bundling manifests'), cnt, unit=_('chunks'))
+                yield chnk
+            self.ui.progress(_('bundling manifests'), None)
+
+            cnt = 0
+            for fname in sorted(changedfiles):
+                filerevlog = self.file(fname)
+                if not len(filerevlog):
+                    raise util.Abort(_("empty or missing revlog for %s") % fname)
+                nodeiter = gennodelst(filerevlog)
+                nodeiter = list(nodeiter)
+                if nodeiter:
+                    yield changegroup.chunkheader(len(fname))
+                    yield fname
+                    lookup = lookuplinkrev_func(filerevlog)
+                    for chnk in filerevlog.group(nodeiter, lookup):
+                        self.ui.progress(
+                            _('bundling files'), cnt, item=fname, unit=_('chunks'))
+                        cnt += 1
+                        yield chnk
+            self.ui.progress(_('bundling files'), None)
+
+            yield changegroup.closechunk()
+
+            if nodes:
+                self.hook('outgoing', node=hex(nodes[0]), source=source)
+
+        return changegroup.unbundle10(util.chunkbuffer(gengroup()), 'UN')
+
+    def addchangegroup(self, source, srctype, url, emptyok=False, lock=None):
+        """Add the changegroup returned by source.read() to this repo.
+        srctype is a string like 'push', 'pull', or 'unbundle'.  url is
+        the URL of the repo where this changegroup is coming from.
+
+        Return an integer summarizing the change to this repo:
+        - nothing changed or no source: 0
+        - more heads than before: 1+added heads (2..n)
+        - fewer heads than before: -1-removed heads (-2..-n)
+        - number of heads stays the same: 1
+        """
+        def csmap(x):
+            self.ui.debug("add changeset %s\n" % short(x))
+            return len(cl)
+
+        def revmap(x):
+            return cl.rev(x)
+
+        if not source:
+            return 0
+
+        self.hook('prechangegroup', throw=True, source=srctype, url=url)
+
+        changesets = files = revisions = 0
+        efiles = set()
+
+        # write changelog data to temp files so concurrent readers will not see
+        # inconsistent view
+        cl = self.changelog
+        cl.delayupdate()
+        oldheads = len(cl.heads())
+
+        tr = self.transaction("\n".join([srctype, urlmod.hidepassword(url)]))
+        try:
+            trp = weakref.proxy(tr)
+            # pull off the changeset group
+            self.ui.status(_("adding changesets\n"))
+            clstart = len(cl)
+            class prog(object):
+                step = _('changesets')
+                count = 1
+                ui = self.ui
+                total = None
+                def __call__(self):
+                    self.ui.progress(self.step, self.count, unit=_('chunks'),
+                                     total=self.total)
+                    self.count += 1
+            pr = prog()
+            source.callback = pr
+
+            if (cl.addgroup(source, csmap, trp) is None
+                and not emptyok):
+                raise util.Abort(_("received changelog group is empty"))
+            clend = len(cl)
+            changesets = clend - clstart
+            for c in xrange(clstart, clend):
+                efiles.update(self[c].files())
+            efiles = len(efiles)
+            self.ui.progress(_('changesets'), None)
+
+            # pull off the manifest group
+            self.ui.status(_("adding manifests\n"))
+            pr.step = _('manifests')
+            pr.count = 1
+            pr.total = changesets # manifests <= changesets
+            # no need to check for empty manifest group here:
+            # if the result of the merge of 1 and 2 is the same in 3 and 4,
+            # no new manifest will be created and the manifest group will
+            # be empty during the pull
+            self.manifest.addgroup(source, revmap, trp)
+            self.ui.progress(_('manifests'), None)
+
+            needfiles = {}
+            if self.ui.configbool('server', 'validate', default=False):
+                # validate incoming csets have their manifests
+                for cset in xrange(clstart, clend):
+                    mfest = self.changelog.read(self.changelog.node(cset))[0]
+                    mfest = self.manifest.readdelta(mfest)
+                    # store file nodes we must see
+                    for f, n in mfest.iteritems():
+                        needfiles.setdefault(f, set()).add(n)
+
+            # process the files
+            self.ui.status(_("adding file changes\n"))
+            pr.step = 'files'
+            pr.count = 1
+            pr.total = efiles
+            source.callback = None
+
+            while 1:
+                f = source.chunk()
+                if not f:
+                    break
+                self.ui.debug("adding %s revisions\n" % f)
+                pr()
+                fl = self.file(f)
+                o = len(fl)
+                if fl.addgroup(source, revmap, trp) is None:
+                    raise util.Abort(_("received file revlog group is empty"))
+                revisions += len(fl) - o
+                files += 1
+                if f in needfiles:
+                    needs = needfiles[f]
+                    for new in xrange(o, len(fl)):
+                        n = fl.node(new)
+                        if n in needs:
+                            needs.remove(n)
+                    if not needs:
+                        del needfiles[f]
+            self.ui.progress(_('files'), None)
+
+            for f, needs in needfiles.iteritems():
+                fl = self.file(f)
+                for n in needs:
+                    try:
+                        fl.rev(n)
+                    except error.LookupError:
+                        raise util.Abort(
+                            _('missing file data for %s:%s - run hg verify') %
+                            (f, hex(n)))
+
+            newheads = len(cl.heads())
+            heads = ""
+            if oldheads and newheads != oldheads:
+                heads = _(" (%+d heads)") % (newheads - oldheads)
+
+            self.ui.status(_("added %d changesets"
+                             " with %d changes to %d files%s\n")
+                             % (changesets, revisions, files, heads))
+
+            if changesets > 0:
+                p = lambda: cl.writepending() and self.root or ""
+                self.hook('pretxnchangegroup', throw=True,
+                          node=hex(cl.node(clstart)), source=srctype,
+                          url=url, pending=p)
+
+            # make changelog see real files again
+            cl.finalize(trp)
+
+            tr.close()
+        finally:
+            tr.release()
+            if lock:
+                lock.release()
+
+        if changesets > 0:
+            # forcefully update the on-disk branch cache
+            self.ui.debug("updating the branch cache\n")
+            self.updatebranchcache()
+            self.hook("changegroup", node=hex(cl.node(clstart)),
+                      source=srctype, url=url)
+
+            for i in xrange(clstart, clend):
+                self.hook("incoming", node=hex(cl.node(i)),
+                          source=srctype, url=url)
+
+        # never return 0 here:
+        if newheads < oldheads:
+            return newheads - oldheads - 1
+        else:
+            return newheads - oldheads + 1
+
+
+    def stream_in(self, remote, requirements):
+        fp = remote.stream_out()
+        l = fp.readline()
+        try:
+            resp = int(l)
+        except ValueError:
+            raise error.ResponseError(
+                _('Unexpected response from remote server:'), l)
+        if resp == 1:
+            raise util.Abort(_('operation forbidden by server'))
+        elif resp == 2:
+            raise util.Abort(_('locking the remote repository failed'))
+        elif resp != 0:
+            raise util.Abort(_('the server sent an unknown error code'))
+        self.ui.status(_('streaming all changes\n'))
+        l = fp.readline()
+        try:
+            total_files, total_bytes = map(int, l.split(' ', 1))
+        except (ValueError, TypeError):
+            raise error.ResponseError(
+                _('Unexpected response from remote server:'), l)
+        self.ui.status(_('%d files to transfer, %s of data\n') %
+                       (total_files, util.bytecount(total_bytes)))
+        start = time.time()
+        for i in xrange(total_files):
+            # XXX doesn't support '\n' or '\r' in filenames
+            l = fp.readline()
+            try:
+                name, size = l.split('\0', 1)
+                size = int(size)
+            except (ValueError, TypeError):
+                raise error.ResponseError(
+                    _('Unexpected response from remote server:'), l)
+            self.ui.debug('adding %s (%s)\n' % (name, util.bytecount(size)))
+            # for backwards compat, name was partially encoded
+            ofp = self.sopener(store.decodedir(name), 'w')
+            for chunk in util.filechunkiter(fp, limit=size):
+                ofp.write(chunk)
+            ofp.close()
+        elapsed = time.time() - start
+        if elapsed <= 0:
+            elapsed = 0.001
+        self.ui.status(_('transferred %s in %.1f seconds (%s/sec)\n') %
+                       (util.bytecount(total_bytes), elapsed,
+                        util.bytecount(total_bytes / elapsed)))
+
+        # new requirements = old non-format requirements + new format-related
+        # requirements from the streamed-in repository
+        requirements.update(set(self.requirements) - self.supportedformats)
+        self._applyrequirements(requirements)
+        self._writerequirements()
+
+        self.invalidate()
+        return len(self.heads()) + 1
+
+    def clone(self, remote, heads=[], stream=False):
+        '''clone remote repository.
+
+        keyword arguments:
+        heads: list of revs to clone (forces use of pull)
+        stream: use streaming clone if possible'''
+
+        # now, all clients that can request uncompressed clones can
+        # read repo formats supported by all servers that can serve
+        # them.
+
+        # if revlog format changes, client will have to check version
+        # and format flags on "stream" capability, and use
+        # uncompressed only if compatible.
+
+        if stream and not heads:
+            # 'stream' means remote revlog format is revlogv1 only
+            if remote.capable('stream'):
+                return self.stream_in(remote, set(('revlogv1',)))
+            # otherwise, 'streamreqs' contains the remote revlog format
+            streamreqs = remote.capable('streamreqs')
+            if streamreqs:
+                streamreqs = set(streamreqs.split(','))
+                # if we support it, stream in and adjust our requirements
+                if not streamreqs - self.supportedformats:
+                    return self.stream_in(remote, streamreqs)
+        return self.pull(remote, heads)
+
+    def pushkey(self, namespace, key, old, new):
+        return pushkey.push(self, namespace, key, old, new)
+
+    def listkeys(self, namespace):
+        return pushkey.list(self, namespace)
+
+# used to avoid circular references so destructors work
+def aftertrans(files):
+    renamefiles = [tuple(t) for t in files]
+    def a():
+        for src, dest in renamefiles:
+            util.rename(src, dest)
+    return a
+
+def instance(ui, path, create):
+    return localrepository(ui, util.drop_scheme('file', path), create)
+
+def islocal(path):
+    return True