comparison hgext3rd/topic/__init__.py @ 4814:48b30ff742cb

python3: use format-source to run byteify-strings in .py files

Using the format-source extension smooth out the pain of merging after
auto-formatting.

This change makes all of the Evolve test suite pass under python3 and has
added benefit of being 100% automated using mercurial's `byteify-strings`
script version 1.0 (revision 11498aa91c036c6d70f7ac5ee5af2664a84a1130).

How to benefit from the help of format-source is explained in the README.

4812:67567d7f1174

    topicmap,
)

cmdtable = {}
command = registrar.command(cmdtable)
colortable = {'topic.active': 'green',
              'topic.list.unstablecount': 'red',
              'topic.list.headcount.multiple': 'yellow',
              'topic.list.behindcount': 'cyan',
              'topic.list.behinderror': 'red',
              'stack.index': 'yellow',
              'stack.index.base': 'none dim',
              'stack.desc.base': 'none dim',
              'stack.shortnode.base': 'none dim',
              'stack.state.base': 'dim',
              'stack.state.clean': 'green',
              'stack.index.current': 'cyan',       # random pick
              'stack.state.current': 'cyan bold',  # random pick
              'stack.desc.current': 'cyan',        # random pick
              'stack.shortnode.current': 'cyan',   # random pick
              'stack.state.orphan': 'red',
              'stack.state.content-divergent': 'red',
              'stack.state.phase-divergent': 'red',
              'stack.summary.behindcount': 'cyan',
              'stack.summary.behinderror': 'red',
              'stack.summary.headcount.multiple': 'yellow',
              # default color to help log output and thg
              # (first pick I could think off, update as needed
              'log.topic': 'green_background',
              'topic.active': 'green',
             }

__version__ = b'0.17.0.dev'

testedwith = b'4.5.2 4.6.2 4.7 4.8 4.9 5.0 5.1'
minimumhgversion = b'4.5'

    from mercurial import configitems

    configtable = {}
    configitem = registrar.configitem(configtable)

    configitem('experimental', 'enforce-topic',
               default=False,
    )
    configitem('experimental', 'enforce-single-head',
               default=False,
    )
    configitem('experimental', 'topic-mode',
               default=None,
    )
    configitem('experimental', 'topic.publish-bare-branch',
               default=False,
    )
    configitem('experimental', 'topic.allow-publish',
               default=configitems.dynamicdefault,
    )
    configitem('_internal', 'keep-topic',
               default=False,
    )
    configitem('experimental', 'topic-mode.server',
               default=configitems.dynamicdefault,
    )

    def extsetup(ui):
        # register config that strictly belong to other code (thg, core, etc)
        #
        # To ensure all config items we used are registered, we register them if
        # nobody else did so far.
        from mercurial import configitems
        extraitem = functools.partial(configitems._register, ui._knownconfig)
        if ('experimental' not in ui._knownconfig
                or not ui._knownconfig['experimental'].get('thg.displaynames')):
            extraitem('experimental', 'thg.displaynames',
                      default=None,
            )
        if ('devel' not in ui._knownconfig
                or not ui._knownconfig['devel'].get('random')):
            extraitem('devel', 'randomseed',
                      default=None,
            )

# we need to do old style declaration for <= 4.5
templatekeyword = registrar.templatekeyword()
post45template = r'requires=' in templatekeyword.__doc__

def _contexttopic(self, force=False):
    if not (force or self.mutable()):
        return ''
    return self.extra().get(constants.extrakey, '')
context.basectx.topic = _contexttopic

def _contexttopicidx(self):
    topic = self.topic()
    if not topic or self.obsolete():

    revs = None
    if stackrev.match(name):
        idx = int(name[1:])
        tname = topic = repo.currenttopic
        if topic:
            ttype = 'topic'
            revs = list(stack.stack(repo, topic=topic))
        else:
            ttype = 'branch'
            tname = branch = repo[None].branch()
            revs = list(stack.stack(repo, branch=branch))
    elif topicrev.match(name):
        idx = int(name[1:])
        ttype = 'topic'
        tname = topic = repo.currenttopic
        if not tname:
            raise error.Abort(_('cannot resolve "%s": no active topic') % name)
        revs = list(stack.stack(repo, topic=topic))

    if revs is not None:
        try:
            r = revs[idx]
        except IndexError:
            if ttype == 'topic':
                msg = _('cannot resolve "%s": %s "%s" has only %d changesets')
            elif ttype == 'branch':
                msg = _('cannot resolve "%s": %s "%s" has only %d non-public changesets')
            raise error.Abort(msg % (name, ttype, tname, len(revs) - 1))
        # t0 or s0 can be None
        if r == -1 and idx == 0:
            msg = _('the %s "%s" has no %s')
            raise error.Abort(msg % (ttype, tname, name))
        return [repo[r].node()]
    if name not in repo.topics:
        return []
    node = repo.changelog.node
    return [node(rev) for rev in repo.revs('topic(%s)', name)]

def _nodemap(repo, node):
    ctx = repo[node]
    t = ctx.topic()
    if t and ctx.phase() > phases.public:

    destination.modsetup(ui)
    discovery.modsetup(ui)
    topicmap.modsetup(ui)
    setupimportexport(ui)

    extensions.afterloaded('rebase', _fixrebase)

    flow.installpushflag(ui)

    entry = extensions.wrapcommand(commands.table, 'commit', commitwrap)
    entry[1].append(('t', 'topic', '',
                     _("use specified topic"), _('TOPIC')))

    entry = extensions.wrapcommand(commands.table, 'push', pushoutgoingwrap)
    entry[1].append(('t', 'topic', '',
                     _("topic to push"), _('TOPIC')))

    entry = extensions.wrapcommand(commands.table, 'outgoing',
                                   pushoutgoingwrap)
    entry[1].append(('t', 'topic', '',
                     _("topic to push"), _('TOPIC')))

    extensions.wrapfunction(cmdutil, 'buildcommittext', committextwrap)
    extensions.wrapfunction(merge, 'update', mergeupdatewrap)
    # We need to check whether t0 or b0 or s0 is passed to override the default update
    # behaviour of changing topic and I can't find a better way
    # to do that as scmutil.revsingle returns the rev number and hence we can't
    # plug into logic for this into mergemod.update().
    extensions.wrapcommand(commands.table, 'update', checkt0)

    try:
        evolve = extensions.find('evolve')
        extensions.wrapfunction(evolve.rewriteutil, "presplitupdate",
                                presplitupdatetopic)
    except (KeyError, AttributeError):
        pass

    cmdutil.summaryhooks.add('topic', summaryhook)

    if not post45template:
        templatekw.keywords['topic'] = topickw
        templatekw.keywords['topicidx'] = topicidxkw
    # Wrap workingctx extra to return the topic name
    extensions.wrapfunction(context.workingctx, '__init__', wrapinit)
    # Wrap changelog.add to drop empty topic
    extensions.wrapfunction(changelog.changelog, 'add', wrapadd)

    if not isinstance(repo, localrepo.localrepository):
        return # this can be a peer in the ssh case (puzzling)

    repo = repo.unfiltered()

    if repo.ui.config('experimental', 'thg.displaynames') is None:
        repo.ui.setconfig('experimental', 'thg.displaynames', 'topics',
                          source='topic-extension')

    class topicrepo(repo.__class__):

        # attribute for other code to distinct between repo with topic and repo without
        hastopicext = True

        def _restrictcapabilities(self, caps):
            caps = super(topicrepo, self)._restrictcapabilities(caps)
            caps.add('topics')
            return caps

        def commit(self, *args, **kwargs):
            backup = self.ui.backupconfig('ui', 'allowemptycommit')
            try:
                if self.currenttopic != self['.'].topic():
                    # bypass the core "nothing changed" logic
                    self.ui.setconfig('ui', 'allowemptycommit', True)
                return super(topicrepo, self).commit(*args, **kwargs)
            finally:
                self.ui.restoreconfig(backup)

        def commitctx(self, ctx, error=None):

            if isinstance(ctx, context.workingcommitctx):
                current = self.currenttopic
                if current:
                    ctx.extra()[constants.extrakey] = current
            if (isinstance(ctx, context.memctx)
                and ctx.extra().get('amend_source')
                and ctx.topic()
                and not self.currenttopic):
                # we are amending and need to remove a topic
                del ctx.extra()[constants.extrakey]
            return super(topicrepo, self).commitctx(ctx, error=error)

        @property
        def topics(self):
            if self._topics is not None:
                return self._topics
            topics = set(['', self.currenttopic])
            for c in self.set('not public()'):
                topics.add(c.topic())
            topics.remove('')
            self._topics = topics
            return topics

        @property
        def currenttopic(self):
            return self.vfs.tryread('topic')

        # overwritten at the instance level by topicmap.py
        _autobranchmaptopic = True

        def branchmap(self, topic=None):

        def branchheads(self, branch=None, start=None, closed=False):
            if branch is None:
                branch = self[None].branch()
            if self.currenttopic:
                branch = "%s:%s" % (branch, self.currenttopic)
            return super(topicrepo, self).branchheads(branch=branch,
                                                      start=start,
                                                      closed=closed)

        def invalidatevolatilesets(self):

            return peer

        def transaction(self, desc, *a, **k):
            ctr = self.currenttransaction()
            tr = super(topicrepo, self).transaction(desc, *a, **k)
            if desc in ('strip', 'repair') or ctr is not None:
                return tr

            reporef = weakref.ref(self)
            if self.ui.configbool('experimental', 'enforce-single-head'):
                if util.safehasattr(tr, 'validator'): # hg <= 4.7
                    origvalidator = tr.validator
                else:
                    origvalidator = tr._validator

                if util.safehasattr(tr, 'validator'): # hg <= 4.7
                    tr.validator = validator
                else:
                    tr._validator = validator

            topicmodeserver = self.ui.config('experimental',
                                             'topic-mode.server', 'ignore')
            ispush = (desc.startswith('push') or desc.startswith('serve'))
            if (topicmodeserver != 'ignore' and ispush):
                if util.safehasattr(tr, 'validator'): # hg <= 4.7
                    origvalidator = tr.validator
                else:
                    origvalidator = tr._validator

                if util.safehasattr(tr, 'validator'): # hg <= 4.7
                    tr.validator = validator
                else:
                    tr._validator = validator

            elif (self.ui.configbool('experimental', 'topic.publish-bare-branch')
                    and (desc.startswith('push')
                         or desc.startswith('serve'))
                    ):
                origclose = tr.close
                trref = weakref.ref(tr)

                def close():
                    repo = reporef()
                    tr2 = trref()
                    flow.publishbarebranch(repo, tr2)
                    origclose()
                tr.close = close
            allow_publish = self.ui.configbool('experimental',
                                               'topic.allow-publish',
                                               True)
            if not allow_publish:
                if util.safehasattr(tr, 'validator'): # hg <= 4.7
                    origvalidator = tr.validator
                else:

                # check active topic emptiness
                repo = reporef()
                csetcount = stack.stack(repo, topic=ct).changesetcount
                empty = csetcount == 0
                if empty and not ctwasempty:
                    ui.status("active topic '%s' is now empty\n" % ct)
                    trnames = getattr(tr, 'names', getattr(tr, '_names', ()))
                    if ('phase' in trnames
                            or any(n.startswith('push-response')
                                   for n in trnames)):
                        ui.status(_("(use 'hg topic --clear' to clear it if needed)\n"))
                hint = _("(see 'hg help topics' for more information)\n")
                if ctwasempty and not empty:
                    if csetcount == 1:
                        msg = _("active topic '%s' grew its first changeset\n%s")
                        ui.status(msg % (ct, hint))
                    else:
                        msg = _("active topic '%s' grew its %s first changesets\n%s")
                        ui.status(msg % (ct, csetcount, hint))

            tr.addpostclose('signalcurrenttopicempty', currenttopicempty)
            return tr

    repo.__class__ = topicrepo
    repo._topics = None
    if util.safehasattr(repo, 'names'):
        repo.names.addnamespace(namespaces.namespace(
            'topics', 'topic', namemap=_namemap, nodemap=_nodemap,
            listnames=lambda repo: repo.topics))

if post45template:
    @templatekeyword(b'topic', requires={b'ctx'})
    def topickw(context, mapping):
        """:topic: String. The topic of the changeset"""
        ctx = context.resource(mapping, 'ctx')
        return ctx.topic()

    @templatekeyword(b'topicidx', requires={b'ctx'})
    def topicidxkw(context, mapping):
        """:topicidx: Integer. Index of the changeset as a stack alias"""
        ctx = context.resource(mapping, 'ctx')
        return ctx.topicidx()
else:
    def topickw(**args):
        """:topic: String. The topic of the changeset"""
        return args['ctx'].topic()

    def topicidxkw(**args):
        """:topicidx: Integer. Index of the changeset as a stack alias"""
        return args['ctx'].topicidx()

def wrapinit(orig, self, repo, *args, **kwargs):
    orig(self, repo, *args, **kwargs)
    if not hastopicext(repo):
        return
    if constants.extrakey not in self._extra:
        if getattr(repo, 'currenttopic', ''):
            self._extra[constants.extrakey] = repo.currenttopic
        else:
            # Empty key will be dropped from extra by another hack at the changegroup level
            self._extra[constants.extrakey] = ''

def wrapadd(orig, cl, manifest, files, desc, transaction, p1, p2, user,
            date=None, extra=None, p1copies=None, p2copies=None,
            filesadded=None, filesremoved=None):
    if constants.extrakey in extra and not extra[constants.extrakey]:

    rev = opts.get('rev')
    current = opts.get('current')
    age = opts.get('age')

    if current and topic:
        raise error.Abort(_("cannot use --current when setting a topic"))
    if current and clear:
        raise error.Abort(_("cannot use --current and --clear"))
    if clear and topic:
        raise error.Abort(_("cannot use --clear when setting a topic"))
    if age and topic:
        raise error.Abort(_("cannot use --age while setting a topic"))

    touchedrevs = set()
    if rev:
        touchedrevs = scmutil.revrange(repo, rev)

    if topic:
        topic = topic.strip()
        if not topic:
            raise error.Abort(_("topic name cannot consist entirely of whitespaces"))
        # Have some restrictions on the topic name just like bookmark name
        scmutil.checknewlabel(repo, topic, 'topic')

        rmatch = re.match(br'[-_.\w]+', topic)
        if not rmatch or rmatch.group(0) != topic:
            helptxt = _("topic names can only consist of alphanumeric, '-'"
                        " '_' and '.' characters")
            raise error.Abort(_("invalid topic name: '%s'") % topic, hint=helptxt)

    if list:
        ui.pager('topics')
        if clear or rev:
            raise error.Abort(_("cannot use --clear or --rev with --list"))
        if not topic:
            topic = repo.currenttopic
        if not topic:
            raise error.Abort(_('no active topic to list'))
        return stack.showstack(ui, repo, topic=topic,
                               opts=pycompat.byteskwargs(opts))

    if touchedrevs:
        if not obsolete.isenabled(repo, obsolete.createmarkersopt):
            raise error.Abort(_('must have obsolete enabled to change topics'))
        if clear:
            topic = None
        elif opts.get('current'):
            topic = repo.currenttopic
        elif not topic:
            raise error.Abort('changing topic requires a topic name or --clear')
        if repo.revs('%ld and public()', touchedrevs):
            raise error.Abort("can't change topic of a public change")
        wl = lock = txn = None
        try:
            wl = repo.wlock()
            lock = repo.lock()
            txn = repo.transaction('rewrite-topics')
            rewrote = _changetopics(ui, repo, touchedrevs, topic)
            txn.close()
            if topic is None:
                ui.status('cleared topic on %d changesets\n' % rewrote)
            else:
                ui.status('changed topic on %d changesets to "%s"\n' % (rewrote,
                                                                        topic))
        finally:
            lockmod.release(txn, lock, wl)
            repo.invalidate()
        return

    ct = repo.currenttopic
    if clear:
        if ct:
            st = stack.stack(repo, topic=ct)
            if not st:
                ui.status(_('clearing empty topic "%s"\n') % ct)
        return _changecurrenttopic(repo, None)

    if topic:
        if not ct:
            ui.status(_('marked working directory as topic: %s\n') % topic)
        return _changecurrenttopic(repo, topic)

    ui.pager('topics')
    # `hg topic --current`
    ret = 0
    if current and not ct:
        ui.write_err(_('no active topic\n'))
        ret = 1
    elif current:
        fm = ui.formatter('topic', pycompat.byteskwargs(opts))
        namemask = '%s\n'
        label = 'topic.active'
        fm.startitem()
        fm.write('topic', namemask, ct, label=label)
        fm.end()
    else:
        _listtopics(ui, repo, opts)
    return ret

@command('stack', [
        ('c', 'children', None,
            _('display data about children outside of the stack'))
    ] + commands.formatteropts,
    _('hg stack [TOPIC]'))
def cmdstack(ui, repo, topic='', **opts):
    """list all changesets in a topic and other information

    List the current topic by default.

    The --verbose version shows short nodes for the commits also.

    branch = None
    if topic is None and repo.currenttopic:
        topic = repo.currenttopic
    if topic is None:
        branch = repo[None].branch()
    ui.pager('stack')
    return stack.showstack(ui, repo, branch=branch, topic=topic,
                           opts=pycompat.byteskwargs(opts))

@command('debugcb|debugconvertbookmark', [
        ('b', 'bookmark', '', _('bookmark to convert to topic')),
        ('', 'all', None, _('convert all bookmarks to topics')),
    ],
    _('[-b BOOKMARK] [--all]'))
def debugconvertbookmark(ui, repo, **opts):
    """Converts a bookmark to a topic with the same name.
    """

    bookmark = opts.get('bookmark')
    convertall = opts.get('all')

    if convertall and bookmark:
        raise error.Abort(_("cannot use '--all' and '-b' together"))
    if not (convertall or bookmark):
        raise error.Abort(_("you must specify either '--all' or '-b'"))

    bmstore = repo._bookmarks

    nodetobook = {}
    for book, revnode in bmstore.items():

        lock = repo.lock()
        if bookmark:
            try:
                node = bmstore[bookmark]
            except KeyError:
                raise error.Abort(_("no such bookmark exists: '%s'") % bookmark)

            revnum = repo[node].rev()
            if len(nodetobook[node]) > 1:
                ui.status(_("skipping revision '%d' as it has multiple bookmarks "
                          "on it\n") % revnum)
                return
            targetrevs = _findconvertbmarktopic(repo, bookmark)
            if targetrevs:
                actions[(bookmark, revnum)] = targetrevs

            for bmark, revnode in sorted(bmstore.items()):
                revnum = repo[revnode].rev()
                if revnum in skipped:
                    continue
                if len(nodetobook[revnode]) > 1:
                    ui.status(_("skipping '%d' as it has multiple bookmarks on"
                              " it\n") % revnum)
                    skipped.append(revnum)
                    continue
                if bmark == '@':
                    continue
                targetrevs = _findconvertbmarktopic(repo, bmark)
                if targetrevs:
                    actions[(bmark, revnum)] = targetrevs

        if actions:
            try:
                tr = repo.transaction('debugconvertbookmark')
                for ((bmark, revnum), targetrevs) in sorted(actions.items()):
                    _applyconvertbmarktopic(ui, repo, targetrevs, revnum, bmark, tr)
                tr.close()
            finally:
                tr.release()
    finally:
        lockmod.release(lock, wlock)

# inspired from mercurial.repair.stripbmrevset
CONVERTBOOKREVSET = """
not public() and (
    ancestors(bookmark(%s))
    and not ancestors(
        (
            (head() and not bookmark(%s))

    # returned an empty set of revisions, so let's skip deleting the
    # bookmark corresponding to which we didn't put a topic on any
    # changeset
    if rewrote == 0:
        return
    ui.status(_('changed topic to "%s" on %d revisions\n') % (bmark,
              rewrote))
    ui.debug('removing bookmark "%s" from "%d"' % (bmark, old))
    bookmarks.delete(repo, tr, [bmark])

def _changecurrenttopic(repo, newtopic):
    """changes the current topic."""

    if newtopic:
        with repo.wlock():
            with repo.vfs.open(b'topic', b'w') as f:
                f.write(newtopic)
    else:
        if repo.vfs.exists('topic'):
            repo.vfs.unlink('topic')

def _changetopics(ui, repo, revs, newtopic):
    """ Changes topic to newtopic of all the revisions in the revset and return
    the count of revisions whose topic has been changed.
    """

            try:
                return c[path]
            except error.ManifestLookupError:
                return None
        fixedextra = dict(c.extra())
        ui.debug('old node id is %s\n' % node.hex(c.node()))
        ui.debug('origextra: %r\n' % fixedextra)
        oldtopic = fixedextra.get(constants.extrakey, None)
        if oldtopic == newtopic:
            continue
        if newtopic is None:
            del fixedextra[constants.extrakey]
        else:
            fixedextra[constants.extrakey] = newtopic
        fixedextra[constants.changekey] = c.hex()
        if 'amend_source' in fixedextra:
            # TODO: right now the commitctx wrapper in
            # topicrepo overwrites the topic in extra if
            # amend_source is set to support 'hg commit
            # --amend'. Support for amend should be adjusted
            # to not be so invasive.
            del fixedextra['amend_source']
        ui.debug('changing topic of %s from %s to %s\n' % (
            c, oldtopic or '<none>', newtopic or '<none>'))
        ui.debug('fixedextra: %r\n' % fixedextra)
        # While changing topic of set of linear commits, make sure that
        # we base our commits on new parent rather than old parent which
        # was obsoleted while changing the topic
        p1 = c.p1().node()
        p2 = c.p2().node()

                            date=c.date(),
                            extra=fixedextra)

        # phase handling
        commitphase = c.phase()
        overrides = {('phases', 'new-commit'): commitphase}
        with repo.ui.configoverride(overrides, 'changetopic'):
            newnode = repo.commitctx(mc)

        successors[c.node()] = (newnode,)
        ui.debug('new node id is %s\n' % node.hex(newnode))
        rewrote += 1

    # create obsmarkers and move bookmarks
    # XXX we should be creating marker as we go instead of only at the end,
    # this makes the operations more modulars
    scmutil.cleanupnodes(repo, successors, 'changetopics')

    # move the working copy too
    wctx = repo[None]
    # in-progress merge is a bit too complex for now.
    if len(wctx.parents()) == 1:

        if newid is not None:
            hg.update(repo, newid[0], quietempty=True)
    return rewrote

def _listtopics(ui, repo, opts):
    fm = ui.formatter('topics', pycompat.byteskwargs(opts))
    activetopic = repo.currenttopic
    namemask = '%s'
    if repo.topics:
        maxwidth = max(len(t) for t in repo.topics)
        namemask = '%%-%is' % maxwidth
    if opts.get('age'):
        # here we sort by age and topic name
        topicsdata = sorted(_getlasttouched(repo, repo.topics))
    else:
        # here we sort by topic name only

            (None, topic, None, None)
            for topic in sorted(repo.topics)
        )
    for age, topic, date, user in topicsdata:
        fm.startitem()
        marker = ' '
        label = 'topic'
        active = (topic == activetopic)
        if active:
            marker = '*'
            label = 'topic.active'
        if not ui.quiet:
            # registering the active data is made explicitly later
            fm.plain(' %s ' % marker, label=label)
        fm.write('topic', namemask, topic, label=label)
        fm.data(active=active)

        if ui.quiet:
            fm.plain('\n')
            continue
        fm.plain(' (')
        if date:
            if age == -1:
                timestr = 'empty and active'
            else:
                timestr = templatefilters.age(date)
            fm.write('lasttouched', '%s', timestr, label='topic.list.time')
        if user:
            fm.write('usertouched', ' by %s', user, label='topic.list.user')
        if date:
            fm.plain(', ')
        data = stack.stack(repo, topic=topic)
        if ui.verbose:
            fm.write('branches+', 'on branch: %s',
                     '+'.join(data.branches), # XXX use list directly after 4.0 is released
                     label='topic.list.branches')

            fm.plain(', ')
        fm.write('changesetcount', '%d changesets', data.changesetcount,
                 label='topic.list.changesetcount')

        if data.unstablecount:
            fm.plain(', ')
            fm.write('unstablecount', '%d unstable',
                     data.unstablecount,
                     label='topic.list.unstablecount')

        headcount = len(data.heads)
        if 1 < headcount:
            fm.plain(', ')
            fm.write('headcount', '%d heads',
                     headcount,
                     label='topic.list.headcount.multiple')

        if ui.verbose:
            # XXX we should include the data even when not verbose

            behindcount = data.behindcount
            if 0 < behindcount:
                fm.plain(', ')
                fm.write('behindcount', '%d behind',
                         behindcount,
                         label='topic.list.behindcount')
            elif -1 == behindcount:
                fm.plain(', ')
                fm.write('behinderror', '%s',
                         _('ambiguous destination: %s') % data.behinderror,
                         label='topic.list.behinderror')
        fm.plain(')\n')
    fm.end()

def _getlasttouched(repo, topics):
    """
    Calculates the last time a topic was used. Returns a generator of 4-tuples:

    curtime = time.time()
    for topic in topics:
        age = -1
        user = None
        maxtime = (0, 0)
        trevs = repo.revs("topic(%s)", topic)
        # Need to check for the time of all changesets in the topic, whether
        # they are obsolete of non-heads
        # XXX: can we just rely on the max rev number for this
        for revs in trevs:
            rt = repo[revs].date()

            # last touch time.
            obsmarkers = compat.getmarkers(repo, [repo[revs].node()])
            for marker in obsmarkers:
                rt = marker.date()
                if rt[0] > maxtime[0]:
                    user = marker.metadata().get('user', user)
                    maxtime = rt

        username = stack.parseusername(user)
        if trevs:
            age = curtime - maxtime[0]

        yield (age, topic, maxtime, username)

def summaryhook(ui, repo):
    t = getattr(repo, 'currenttopic', '')
    if not t:
        return
    # i18n: column positioning for "hg summary"
    ui.write(_("topic:  %s\n") % ui.label(t, 'topic.active'))

_validmode = [
    'ignore',
    'warning',
    'enforce',
    'enforce-all',
    'random',
    'random-all',
]

def _configtopicmode(ui):
    """ Parse the config to get the topicmode
    """
    topicmode = ui.config('experimental', 'topic-mode')

    # Fallback to read enforce-topic
    if topicmode is None:
        enforcetopic = ui.configbool('experimental', 'enforce-topic')
        if enforcetopic:
            topicmode = "enforce"
    if topicmode not in _validmode:
        topicmode = _validmode[0]

    return topicmode

    with repo.wlock():
        topicmode = _configtopicmode(ui)
        ismergecommit = len(repo[None].parents()) == 2

        notopic = not repo.currenttopic
        mayabort = (topicmode == "enforce" and not ismergecommit)
        maywarn = (topicmode == "warning"
                   or (topicmode == "enforce" and ismergecommit))

        mayrandom = False
        if topicmode == "random":
            mayrandom = not ismergecommit
        elif topicmode == "random-all":
            mayrandom = True

        if topicmode == 'enforce-all':
            ismergecommit = False
            mayabort = True
            maywarn = False

        hint = _("see 'hg help -e topic.topic-mode' for details")
        if opts.get('topic'):
            t = opts['topic']
            with repo.vfs.open(b'topic', b'w') as f:
                f.write(t)
        elif opts.get('amend'):
            pass
        elif notopic and mayabort:
            msg = _("no active topic")
            raise error.Abort(msg, hint=hint)
        elif notopic and maywarn:
            ui.warn(_("warning: new draft commit without topic\n"))
            if not ui.quiet:
                ui.warn(("(%s)\n") % hint)
        elif notopic and mayrandom:
            with repo.vfs.open(b'topic', b'w') as f:
                f.write(randomname.randomtopicname(ui))
        return orig(ui, repo, *args, **opts)

def committextwrap(orig, repo, ctx, subs, extramsg):
    ret = orig(repo, ctx, subs, extramsg)
    if hastopicext(repo):
        t = repo.currenttopic
        if t:
            ret = ret.replace("\nHG: branch",
                              "\nHG: topic '%s'\nHG: branch" % t)
    return ret

def pushoutgoingwrap(orig, ui, repo, *args, **opts):
    if opts.get('topic'):
        topicrevs = repo.revs('topic(%s) - obsolete()', opts['topic'])
        opts.setdefault('rev', []).extend(topicrevs)
    return orig(ui, repo, *args, **opts)

def mergeupdatewrap(orig, repo, node, branchmerge, force, *args, **kwargs):
    matcher = kwargs.get('matcher')

        # current topic. This is right for merge but wrong for rebase. We check
        # if rebase is running and update the currenttopic to topic of new
        # rebased commit. We have explicitly stored in config if rebase is
        # running.
        ot = repo.currenttopic
        if repo.ui.hasconfig('experimental', 'topicrebase'):
            isrebase = True
        if repo.ui.configbool('_internal', 'keep-topic'):
            ist0 = True
        if ((not partial and not branchmerge) or isrebase) and not ist0:
            t = ''
            pctx = repo[node]
            if pctx.phase() > phases.public:
                t = pctx.topic()
            with repo.vfs.open(b'topic', b'w') as f:
                f.write(t)
            if t and t != ot:
                repo.ui.status(_("switching to topic %s\n") % t)
            if ot and not t:
                st = stack.stack(repo, topic=ot)
                if not st:
                    repo.ui.status(_('clearing empty topic "%s"\n') % ot)
        elif ist0:
            repo.ui.status(_("preserving the current topic '%s'\n") % ot)
        return ret
    finally:
        wlock.release()

def checkt0(orig, ui, repo, node=None, rev=None, *args, **kwargs):

    thezeros = set(['t0', 'b0', 's0'])
    backup = repo.ui.backupconfig('_internal', 'keep-topic')
    try:
        if node in thezeros or rev in thezeros:
            repo.ui.setconfig('_internal', 'keep-topic', 'yes',
                              source='topic-extension')
        return orig(ui, repo, node=node, rev=rev, *args, **kwargs)
    finally:
        repo.ui.restoreconfig(backup)

def _fixrebase(loaded):

    def savetopic(ctx, extra):
        if ctx.topic():
            extra[constants.extrakey] = ctx.topic()

    def setrebaseconfig(orig, ui, repo, **opts):
        repo.ui.setconfig('experimental', 'topicrebase', 'yes',
                          source='topic-extension')
        return orig(ui, repo, **opts)

    def new_init(orig, *args, **kwargs):
        runtime = orig(*args, **kwargs)

            runtime.extrafns.append(savetopic)

        return runtime

    try:
        rebase = extensions.find("rebase")
        extensions.wrapfunction(rebase.rebaseruntime, '__init__', new_init)
        # This exists to store in the config that rebase is running so that we can
        # update the topic according to rebase. This is a hack and should be removed
        # when we have better options.
        extensions.wrapcommand(rebase.cmdtable, 'rebase', setrebaseconfig)
    except KeyError:
        pass

## preserve topic during import/export

def _exporttopic(seq, ctx):
    topic = ctx.topic()
    if topic:
        return 'EXP-Topic %s' % topic
    return None

def _importtopic(repo, patchdata, extra, opts):
    if 'topic' in patchdata:
        extra['topic'] = patchdata['topic']

def setupimportexport(ui):
    """run at ui setup time to install import/export logic"""
    cmdutil.extraexport.append('topic')
    cmdutil.extraexportmap['topic'] = _exporttopic
    cmdutil.extrapreimport.append('topic')
    cmdutil.extrapreimportmap['topic'] = _importtopic
    patch.patchheadermap.append(('EXP-Topic', 'topic'))

## preserve topic during split

def presplitupdatetopic(original, repo, ui, prev, ctx):
    # Save topic of revision

4814:48b30ff742cb

    topicmap,
)

cmdtable = {}
command = registrar.command(cmdtable)
colortable = {b'topic.active': b'green',
              b'topic.list.unstablecount': b'red',
              b'topic.list.headcount.multiple': b'yellow',
              b'topic.list.behindcount': b'cyan',
              b'topic.list.behinderror': b'red',
              b'stack.index': b'yellow',
              b'stack.index.base': b'none dim',
              b'stack.desc.base': b'none dim',
              b'stack.shortnode.base': b'none dim',
              b'stack.state.base': b'dim',
              b'stack.state.clean': b'green',
              b'stack.index.current': b'cyan',       # random pick
              b'stack.state.current': b'cyan bold',  # random pick
              b'stack.desc.current': b'cyan',        # random pick
              b'stack.shortnode.current': b'cyan',   # random pick
              b'stack.state.orphan': b'red',
              b'stack.state.content-divergent': b'red',
              b'stack.state.phase-divergent': b'red',
              b'stack.summary.behindcount': b'cyan',
              b'stack.summary.behinderror': b'red',
              b'stack.summary.headcount.multiple': b'yellow',
              # default color to help log output and thg
              # (first pick I could think off, update as needed
              b'log.topic': b'green_background',
              b'topic.active': b'green',
              }

__version__ = b'0.17.0.dev'

testedwith = b'4.5.2 4.6.2 4.7 4.8 4.9 5.0 5.1'
minimumhgversion = b'4.5'

    from mercurial import configitems

    configtable = {}
    configitem = registrar.configitem(configtable)

    configitem(b'experimental', b'enforce-topic',
               default=False,
    )
    configitem(b'experimental', b'enforce-single-head',
               default=False,
    )
    configitem(b'experimental', b'topic-mode',
               default=None,
    )
    configitem(b'experimental', b'topic.publish-bare-branch',
               default=False,
    )
    configitem(b'experimental', b'topic.allow-publish',
               default=configitems.dynamicdefault,
    )
    configitem(b'_internal', b'keep-topic',
               default=False,
    )
    configitem(b'experimental', b'topic-mode.server',
               default=configitems.dynamicdefault,
    )

    def extsetup(ui):
        # register config that strictly belong to other code (thg, core, etc)
        #
        # To ensure all config items we used are registered, we register them if
        # nobody else did so far.
        from mercurial import configitems
        extraitem = functools.partial(configitems._register, ui._knownconfig)
        if (b'experimental' not in ui._knownconfig
                or not ui._knownconfig[b'experimental'].get(b'thg.displaynames')):
            extraitem(b'experimental', b'thg.displaynames',
                      default=None,
            )
        if (b'devel' not in ui._knownconfig
                or not ui._knownconfig[b'devel'].get(b'random')):
            extraitem(b'devel', b'randomseed',
                      default=None,
            )

# we need to do old style declaration for <= 4.5
templatekeyword = registrar.templatekeyword()
post45template = r'requires=' in templatekeyword.__doc__

def _contexttopic(self, force=False):
    if not (force or self.mutable()):
        return b''
    return self.extra().get(constants.extrakey, b'')
context.basectx.topic = _contexttopic

def _contexttopicidx(self):
    topic = self.topic()
    if not topic or self.obsolete():

    revs = None
    if stackrev.match(name):
        idx = int(name[1:])
        tname = topic = repo.currenttopic
        if topic:
            ttype = b'topic'
            revs = list(stack.stack(repo, topic=topic))
        else:
            ttype = b'branch'
            tname = branch = repo[None].branch()
            revs = list(stack.stack(repo, branch=branch))
    elif topicrev.match(name):
        idx = int(name[1:])
        ttype = b'topic'
        tname = topic = repo.currenttopic
        if not tname:
            raise error.Abort(_(b'cannot resolve "%s": no active topic') % name)
        revs = list(stack.stack(repo, topic=topic))

    if revs is not None:
        try:
            r = revs[idx]
        except IndexError:
            if ttype == b'topic':
                msg = _(b'cannot resolve "%s": %s "%s" has only %d changesets')
            elif ttype == b'branch':
                msg = _(b'cannot resolve "%s": %s "%s" has only %d non-public changesets')
            raise error.Abort(msg % (name, ttype, tname, len(revs) - 1))
        # t0 or s0 can be None
        if r == -1 and idx == 0:
            msg = _(b'the %s "%s" has no %s')
            raise error.Abort(msg % (ttype, tname, name))
        return [repo[r].node()]
    if name not in repo.topics:
        return []
    node = repo.changelog.node
    return [node(rev) for rev in repo.revs(b'topic(%s)', name)]

def _nodemap(repo, node):
    ctx = repo[node]
    t = ctx.topic()
    if t and ctx.phase() > phases.public:

    destination.modsetup(ui)
    discovery.modsetup(ui)
    topicmap.modsetup(ui)
    setupimportexport(ui)

    extensions.afterloaded(b'rebase', _fixrebase)

    flow.installpushflag(ui)

    entry = extensions.wrapcommand(commands.table, b'commit', commitwrap)
    entry[1].append((b't', b'topic', b'',
                     _(b"use specified topic"), _(b'TOPIC')))

    entry = extensions.wrapcommand(commands.table, b'push', pushoutgoingwrap)
    entry[1].append((b't', b'topic', b'',
                     _(b"topic to push"), _(b'TOPIC')))

    entry = extensions.wrapcommand(commands.table, b'outgoing',
                                   pushoutgoingwrap)
    entry[1].append((b't', b'topic', b'',
                     _(b"topic to push"), _(b'TOPIC')))

    extensions.wrapfunction(cmdutil, 'buildcommittext', committextwrap)
    extensions.wrapfunction(merge, 'update', mergeupdatewrap)
    # We need to check whether t0 or b0 or s0 is passed to override the default update
    # behaviour of changing topic and I can't find a better way
    # to do that as scmutil.revsingle returns the rev number and hence we can't
    # plug into logic for this into mergemod.update().
    extensions.wrapcommand(commands.table, b'update', checkt0)

    try:
        evolve = extensions.find(b'evolve')
        extensions.wrapfunction(evolve.rewriteutil, "presplitupdate",
                                presplitupdatetopic)
    except (KeyError, AttributeError):
        pass

    cmdutil.summaryhooks.add(b'topic', summaryhook)

    if not post45template:
        templatekw.keywords[b'topic'] = topickw
        templatekw.keywords[b'topicidx'] = topicidxkw
    # Wrap workingctx extra to return the topic name
    extensions.wrapfunction(context.workingctx, '__init__', wrapinit)
    # Wrap changelog.add to drop empty topic
    extensions.wrapfunction(changelog.changelog, 'add', wrapadd)

    if not isinstance(repo, localrepo.localrepository):
        return # this can be a peer in the ssh case (puzzling)

    repo = repo.unfiltered()

    if repo.ui.config(b'experimental', b'thg.displaynames') is None:
        repo.ui.setconfig(b'experimental', b'thg.displaynames', b'topics',
                          source=b'topic-extension')

    class topicrepo(repo.__class__):

        # attribute for other code to distinct between repo with topic and repo without
        hastopicext = True

        def _restrictcapabilities(self, caps):
            caps = super(topicrepo, self)._restrictcapabilities(caps)
            caps.add(b'topics')
            return caps

        def commit(self, *args, **kwargs):
            backup = self.ui.backupconfig(b'ui', b'allowemptycommit')
            try:
                if self.currenttopic != self[b'.'].topic():
                    # bypass the core "nothing changed" logic
                    self.ui.setconfig(b'ui', b'allowemptycommit', True)
                return super(topicrepo, self).commit(*args, **kwargs)
            finally:
                self.ui.restoreconfig(backup)

        def commitctx(self, ctx, error=None):

            if isinstance(ctx, context.workingcommitctx):
                current = self.currenttopic
                if current:
                    ctx.extra()[constants.extrakey] = current
            if (isinstance(ctx, context.memctx)
                and ctx.extra().get(b'amend_source')
                and ctx.topic()
                and not self.currenttopic):
                # we are amending and need to remove a topic
                del ctx.extra()[constants.extrakey]
            return super(topicrepo, self).commitctx(ctx, error=error)

        @property
        def topics(self):
            if self._topics is not None:
                return self._topics
            topics = set([b'', self.currenttopic])
            for c in self.set(b'not public()'):
                topics.add(c.topic())
            topics.remove(b'')
            self._topics = topics
            return topics

        @property
        def currenttopic(self):
            return self.vfs.tryread(b'topic')

        # overwritten at the instance level by topicmap.py
        _autobranchmaptopic = True

        def branchmap(self, topic=None):

        def branchheads(self, branch=None, start=None, closed=False):
            if branch is None:
                branch = self[None].branch()
            if self.currenttopic:
                branch = b"%s:%s" % (branch, self.currenttopic)
            return super(topicrepo, self).branchheads(branch=branch,
                                                      start=start,
                                                      closed=closed)

        def invalidatevolatilesets(self):

            return peer

        def transaction(self, desc, *a, **k):
            ctr = self.currenttransaction()
            tr = super(topicrepo, self).transaction(desc, *a, **k)
            if desc in (b'strip', b'repair') or ctr is not None:
                return tr

            reporef = weakref.ref(self)
            if self.ui.configbool(b'experimental', b'enforce-single-head'):
                if util.safehasattr(tr, 'validator'): # hg <= 4.7
                    origvalidator = tr.validator
                else:
                    origvalidator = tr._validator

                if util.safehasattr(tr, 'validator'): # hg <= 4.7
                    tr.validator = validator
                else:
                    tr._validator = validator

            topicmodeserver = self.ui.config(b'experimental',
                                             b'topic-mode.server', b'ignore')
            ispush = (desc.startswith(b'push') or desc.startswith(b'serve'))
            if (topicmodeserver != b'ignore' and ispush):
                if util.safehasattr(tr, 'validator'): # hg <= 4.7
                    origvalidator = tr.validator
                else:
                    origvalidator = tr._validator

                if util.safehasattr(tr, 'validator'): # hg <= 4.7
                    tr.validator = validator
                else:
                    tr._validator = validator

            elif (self.ui.configbool(b'experimental', b'topic.publish-bare-branch')
                    and (desc.startswith(b'push')
                         or desc.startswith(b'serve'))
                    ):
                origclose = tr.close
                trref = weakref.ref(tr)

                def close():
                    repo = reporef()
                    tr2 = trref()
                    flow.publishbarebranch(repo, tr2)
                    origclose()
                tr.close = close
            allow_publish = self.ui.configbool(b'experimental',
                                               b'topic.allow-publish',
                                               True)
            if not allow_publish:
                if util.safehasattr(tr, 'validator'): # hg <= 4.7
                    origvalidator = tr.validator
                else:

                # check active topic emptiness
                repo = reporef()
                csetcount = stack.stack(repo, topic=ct).changesetcount
                empty = csetcount == 0
                if empty and not ctwasempty:
                    ui.status(b"active topic '%s' is now empty\n" % ct)
                    trnames = getattr(tr, 'names', getattr(tr, '_names', ()))
                    if (b'phase' in trnames
                            or any(n.startswith(b'push-response')
                                   for n in trnames)):
                        ui.status(_(b"(use 'hg topic --clear' to clear it if needed)\n"))
                hint = _(b"(see 'hg help topics' for more information)\n")
                if ctwasempty and not empty:
                    if csetcount == 1:
                        msg = _(b"active topic '%s' grew its first changeset\n%s")
                        ui.status(msg % (ct, hint))
                    else:
                        msg = _(b"active topic '%s' grew its %s first changesets\n%s")
                        ui.status(msg % (ct, csetcount, hint))

            tr.addpostclose(b'signalcurrenttopicempty', currenttopicempty)
            return tr

    repo.__class__ = topicrepo
    repo._topics = None
    if util.safehasattr(repo, 'names'):
        repo.names.addnamespace(namespaces.namespace(
            b'topics', b'topic', namemap=_namemap, nodemap=_nodemap,
            listnames=lambda repo: repo.topics))

if post45template:
    @templatekeyword(b'topic', requires={b'ctx'})
    def topickw(context, mapping):
        """:topic: String. The topic of the changeset"""
        ctx = context.resource(mapping, b'ctx')
        return ctx.topic()

    @templatekeyword(b'topicidx', requires={b'ctx'})
    def topicidxkw(context, mapping):
        """:topicidx: Integer. Index of the changeset as a stack alias"""
        ctx = context.resource(mapping, b'ctx')
        return ctx.topicidx()
else:
    def topickw(**args):
        """:topic: String. The topic of the changeset"""
        return args[b'ctx'].topic()

    def topicidxkw(**args):
        """:topicidx: Integer. Index of the changeset as a stack alias"""
        return args[b'ctx'].topicidx()

def wrapinit(orig, self, repo, *args, **kwargs):
    orig(self, repo, *args, **kwargs)
    if not hastopicext(repo):
        return
    if constants.extrakey not in self._extra:
        if getattr(repo, 'currenttopic', b''):
            self._extra[constants.extrakey] = repo.currenttopic
        else:
            # Empty key will be dropped from extra by another hack at the changegroup level
            self._extra[constants.extrakey] = b''

def wrapadd(orig, cl, manifest, files, desc, transaction, p1, p2, user,
            date=None, extra=None, p1copies=None, p2copies=None,
            filesadded=None, filesremoved=None):
    if constants.extrakey in extra and not extra[constants.extrakey]:

    rev = opts.get('rev')
    current = opts.get('current')
    age = opts.get('age')

    if current and topic:
        raise error.Abort(_(b"cannot use --current when setting a topic"))
    if current and clear:
        raise error.Abort(_(b"cannot use --current and --clear"))
    if clear and topic:
        raise error.Abort(_(b"cannot use --clear when setting a topic"))
    if age and topic:
        raise error.Abort(_(b"cannot use --age while setting a topic"))

    touchedrevs = set()
    if rev:
        touchedrevs = scmutil.revrange(repo, rev)

    if topic:
        topic = topic.strip()
        if not topic:
            raise error.Abort(_(b"topic name cannot consist entirely of whitespaces"))
        # Have some restrictions on the topic name just like bookmark name
        scmutil.checknewlabel(repo, topic, b'topic')

        rmatch = re.match(br'[-_.\w]+', topic)
        if not rmatch or rmatch.group(0) != topic:
            helptxt = _(b"topic names can only consist of alphanumeric, '-'"
                        b" '_' and '.' characters")
            raise error.Abort(_(b"invalid topic name: '%s'") % topic, hint=helptxt)

    if list:
        ui.pager(b'topics')
        if clear or rev:
            raise error.Abort(_(b"cannot use --clear or --rev with --list"))
        if not topic:
            topic = repo.currenttopic
        if not topic:
            raise error.Abort(_(b'no active topic to list'))
        return stack.showstack(ui, repo, topic=topic,
                               opts=pycompat.byteskwargs(opts))

    if touchedrevs:
        if not obsolete.isenabled(repo, obsolete.createmarkersopt):
            raise error.Abort(_(b'must have obsolete enabled to change topics'))
        if clear:
            topic = None
        elif opts.get('current'):
            topic = repo.currenttopic
        elif not topic:
            raise error.Abort(b'changing topic requires a topic name or --clear')
        if repo.revs(b'%ld and public()', touchedrevs):
            raise error.Abort(b"can't change topic of a public change")
        wl = lock = txn = None
        try:
            wl = repo.wlock()
            lock = repo.lock()
            txn = repo.transaction(b'rewrite-topics')
            rewrote = _changetopics(ui, repo, touchedrevs, topic)
            txn.close()
            if topic is None:
                ui.status(b'cleared topic on %d changesets\n' % rewrote)
            else:
                ui.status(b'changed topic on %d changesets to "%s"\n' % (rewrote,
                                                                         topic))
        finally:
            lockmod.release(txn, lock, wl)
            repo.invalidate()
        return

    ct = repo.currenttopic
    if clear:
        if ct:
            st = stack.stack(repo, topic=ct)
            if not st:
                ui.status(_(b'clearing empty topic "%s"\n') % ct)
        return _changecurrenttopic(repo, None)

    if topic:
        if not ct:
            ui.status(_(b'marked working directory as topic: %s\n') % topic)
        return _changecurrenttopic(repo, topic)

    ui.pager(b'topics')
    # `hg topic --current`
    ret = 0
    if current and not ct:
        ui.write_err(_(b'no active topic\n'))
        ret = 1
    elif current:
        fm = ui.formatter(b'topic', pycompat.byteskwargs(opts))
        namemask = b'%s\n'
        label = b'topic.active'
        fm.startitem()
        fm.write(b'topic', namemask, ct, label=label)
        fm.end()
    else:
        _listtopics(ui, repo, opts)
    return ret

@command(b'stack', [
        (b'c', b'children', None,
            _(b'display data about children outside of the stack'))
    ] + commands.formatteropts,
    _(b'hg stack [TOPIC]'))
def cmdstack(ui, repo, topic=b'', **opts):
    """list all changesets in a topic and other information

    List the current topic by default.

    The --verbose version shows short nodes for the commits also.

    branch = None
    if topic is None and repo.currenttopic:
        topic = repo.currenttopic
    if topic is None:
        branch = repo[None].branch()
    ui.pager(b'stack')
    return stack.showstack(ui, repo, branch=branch, topic=topic,
                           opts=pycompat.byteskwargs(opts))

@command(b'debugcb|debugconvertbookmark', [
        (b'b', b'bookmark', b'', _(b'bookmark to convert to topic')),
        (b'', b'all', None, _(b'convert all bookmarks to topics')),
    ],
    _(b'[-b BOOKMARK] [--all]'))
def debugconvertbookmark(ui, repo, **opts):
    """Converts a bookmark to a topic with the same name.
    """

    bookmark = opts.get('bookmark')
    convertall = opts.get('all')

    if convertall and bookmark:
        raise error.Abort(_(b"cannot use '--all' and '-b' together"))
    if not (convertall or bookmark):
        raise error.Abort(_(b"you must specify either '--all' or '-b'"))

    bmstore = repo._bookmarks

    nodetobook = {}
    for book, revnode in bmstore.items():

        lock = repo.lock()
        if bookmark:
            try:
                node = bmstore[bookmark]
            except KeyError:
                raise error.Abort(_(b"no such bookmark exists: '%s'") % bookmark)

            revnum = repo[node].rev()
            if len(nodetobook[node]) > 1:
                ui.status(_(b"skipping revision '%d' as it has multiple bookmarks "
                          b"on it\n") % revnum)
                return
            targetrevs = _findconvertbmarktopic(repo, bookmark)
            if targetrevs:
                actions[(bookmark, revnum)] = targetrevs

            for bmark, revnode in sorted(bmstore.items()):
                revnum = repo[revnode].rev()
                if revnum in skipped:
                    continue
                if len(nodetobook[revnode]) > 1:
                    ui.status(_(b"skipping '%d' as it has multiple bookmarks on"
                              b" it\n") % revnum)
                    skipped.append(revnum)
                    continue
                if bmark == b'@':
                    continue
                targetrevs = _findconvertbmarktopic(repo, bmark)
                if targetrevs:
                    actions[(bmark, revnum)] = targetrevs

        if actions:
            try:
                tr = repo.transaction(b'debugconvertbookmark')
                for ((bmark, revnum), targetrevs) in sorted(actions.items()):
                    _applyconvertbmarktopic(ui, repo, targetrevs, revnum, bmark, tr)
                tr.close()
            finally:
                tr.release()
    finally:
        lockmod.release(lock, wlock)

# inspired from mercurial.repair.stripbmrevset
CONVERTBOOKREVSET = b"""
not public() and (
    ancestors(bookmark(%s))
    and not ancestors(
        (
            (head() and not bookmark(%s))

    # returned an empty set of revisions, so let's skip deleting the
    # bookmark corresponding to which we didn't put a topic on any
    # changeset
    if rewrote == 0:
        return
    ui.status(_(b'changed topic to "%s" on %d revisions\n') % (bmark,
              rewrote))
    ui.debug(b'removing bookmark "%s" from "%d"' % (bmark, old))
    bookmarks.delete(repo, tr, [bmark])

def _changecurrenttopic(repo, newtopic):
    """changes the current topic."""

    if newtopic:
        with repo.wlock():
            with repo.vfs.open(b'topic', b'w') as f:
                f.write(newtopic)
    else:
        if repo.vfs.exists(b'topic'):
            repo.vfs.unlink(b'topic')

def _changetopics(ui, repo, revs, newtopic):
    """ Changes topic to newtopic of all the revisions in the revset and return
    the count of revisions whose topic has been changed.
    """

            try:
                return c[path]
            except error.ManifestLookupError:
                return None
        fixedextra = dict(c.extra())
        ui.debug(b'old node id is %s\n' % node.hex(c.node()))
        ui.debug(b'origextra: %r\n' % fixedextra)
        oldtopic = fixedextra.get(constants.extrakey, None)
        if oldtopic == newtopic:
            continue
        if newtopic is None:
            del fixedextra[constants.extrakey]
        else:
            fixedextra[constants.extrakey] = newtopic
        fixedextra[constants.changekey] = c.hex()
        if b'amend_source' in fixedextra:
            # TODO: right now the commitctx wrapper in
            # topicrepo overwrites the topic in extra if
            # amend_source is set to support 'hg commit
            # --amend'. Support for amend should be adjusted
            # to not be so invasive.
            del fixedextra[b'amend_source']
        ui.debug(b'changing topic of %s from %s to %s\n' % (
            c, oldtopic or b'<none>', newtopic or b'<none>'))
        ui.debug(b'fixedextra: %r\n' % fixedextra)
        # While changing topic of set of linear commits, make sure that
        # we base our commits on new parent rather than old parent which
        # was obsoleted while changing the topic
        p1 = c.p1().node()
        p2 = c.p2().node()

                            date=c.date(),
                            extra=fixedextra)

        # phase handling
        commitphase = c.phase()
        overrides = {(b'phases', b'new-commit'): commitphase}
        with repo.ui.configoverride(overrides, b'changetopic'):
            newnode = repo.commitctx(mc)

        successors[c.node()] = (newnode,)
        ui.debug(b'new node id is %s\n' % node.hex(newnode))
        rewrote += 1

    # create obsmarkers and move bookmarks
    # XXX we should be creating marker as we go instead of only at the end,
    # this makes the operations more modulars
    scmutil.cleanupnodes(repo, successors, b'changetopics')

    # move the working copy too
    wctx = repo[None]
    # in-progress merge is a bit too complex for now.
    if len(wctx.parents()) == 1:

        if newid is not None:
            hg.update(repo, newid[0], quietempty=True)
    return rewrote

def _listtopics(ui, repo, opts):
    fm = ui.formatter(b'topics', pycompat.byteskwargs(opts))
    activetopic = repo.currenttopic
    namemask = b'%s'
    if repo.topics:
        maxwidth = max(len(t) for t in repo.topics)
        namemask = b'%%-%is' % maxwidth
    if opts.get('age'):
        # here we sort by age and topic name
        topicsdata = sorted(_getlasttouched(repo, repo.topics))
    else:
        # here we sort by topic name only

            (None, topic, None, None)
            for topic in sorted(repo.topics)
        )
    for age, topic, date, user in topicsdata:
        fm.startitem()
        marker = b' '
        label = b'topic'
        active = (topic == activetopic)
        if active:
            marker = b'*'
            label = b'topic.active'
        if not ui.quiet:
            # registering the active data is made explicitly later
            fm.plain(b' %s ' % marker, label=label)
        fm.write(b'topic', namemask, topic, label=label)
        fm.data(active=active)

        if ui.quiet:
            fm.plain(b'\n')
            continue
        fm.plain(b' (')
        if date:
            if age == -1:
                timestr = b'empty and active'
            else:
                timestr = templatefilters.age(date)
            fm.write(b'lasttouched', b'%s', timestr, label=b'topic.list.time')
        if user:
            fm.write(b'usertouched', b' by %s', user, label=b'topic.list.user')
        if date:
            fm.plain(b', ')
        data = stack.stack(repo, topic=topic)
        if ui.verbose:
            fm.write(b'branches+', b'on branch: %s',
                     b'+'.join(data.branches), # XXX use list directly after 4.0 is released
                     label=b'topic.list.branches')

            fm.plain(b', ')
        fm.write(b'changesetcount', b'%d changesets', data.changesetcount,
                 label=b'topic.list.changesetcount')

        if data.unstablecount:
            fm.plain(b', ')
            fm.write(b'unstablecount', b'%d unstable',
                     data.unstablecount,
                     label=b'topic.list.unstablecount')

        headcount = len(data.heads)
        if 1 < headcount:
            fm.plain(b', ')
            fm.write(b'headcount', b'%d heads',
                     headcount,
                     label=b'topic.list.headcount.multiple')

        if ui.verbose:
            # XXX we should include the data even when not verbose

            behindcount = data.behindcount
            if 0 < behindcount:
                fm.plain(b', ')
                fm.write(b'behindcount', b'%d behind',
                         behindcount,
                         label=b'topic.list.behindcount')
            elif -1 == behindcount:
                fm.plain(b', ')
                fm.write(b'behinderror', b'%s',
                         _(b'ambiguous destination: %s') % data.behinderror,
                         label=b'topic.list.behinderror')
        fm.plain(b')\n')
    fm.end()

def _getlasttouched(repo, topics):
    """
    Calculates the last time a topic was used. Returns a generator of 4-tuples:

    curtime = time.time()
    for topic in topics:
        age = -1
        user = None
        maxtime = (0, 0)
        trevs = repo.revs(b"topic(%s)", topic)
        # Need to check for the time of all changesets in the topic, whether
        # they are obsolete of non-heads
        # XXX: can we just rely on the max rev number for this
        for revs in trevs:
            rt = repo[revs].date()

            # last touch time.
            obsmarkers = compat.getmarkers(repo, [repo[revs].node()])
            for marker in obsmarkers:
                rt = marker.date()
                if rt[0] > maxtime[0]:
                    user = marker.metadata().get(b'user', user)
                    maxtime = rt

        username = stack.parseusername(user)
        if trevs:
            age = curtime - maxtime[0]

        yield (age, topic, maxtime, username)

def summaryhook(ui, repo):
    t = getattr(repo, 'currenttopic', b'')
    if not t:
        return
    # i18n: column positioning for "hg summary"
    ui.write(_(b"topic:  %s\n") % ui.label(t, b'topic.active'))

_validmode = [
    b'ignore',
    b'warning',
    b'enforce',
    b'enforce-all',
    b'random',
    b'random-all',
]

def _configtopicmode(ui):
    """ Parse the config to get the topicmode
    """
    topicmode = ui.config(b'experimental', b'topic-mode')

    # Fallback to read enforce-topic
    if topicmode is None:
        enforcetopic = ui.configbool(b'experimental', b'enforce-topic')
        if enforcetopic:
            topicmode = b"enforce"
    if topicmode not in _validmode:
        topicmode = _validmode[0]

    return topicmode

    with repo.wlock():
        topicmode = _configtopicmode(ui)
        ismergecommit = len(repo[None].parents()) == 2

        notopic = not repo.currenttopic
        mayabort = (topicmode == b"enforce" and not ismergecommit)
        maywarn = (topicmode == b"warning"
                   or (topicmode == b"enforce" and ismergecommit))

        mayrandom = False
        if topicmode == b"random":
            mayrandom = not ismergecommit
        elif topicmode == b"random-all":
            mayrandom = True

        if topicmode == b'enforce-all':
            ismergecommit = False
            mayabort = True
            maywarn = False

        hint = _(b"see 'hg help -e topic.topic-mode' for details")
        if opts.get('topic'):
            t = opts['topic']
            with repo.vfs.open(b'topic', b'w') as f:
                f.write(t)
        elif opts.get('amend'):
            pass
        elif notopic and mayabort:
            msg = _(b"no active topic")
            raise error.Abort(msg, hint=hint)
        elif notopic and maywarn:
            ui.warn(_(b"warning: new draft commit without topic\n"))
            if not ui.quiet:
                ui.warn((b"(%s)\n") % hint)
        elif notopic and mayrandom:
            with repo.vfs.open(b'topic', b'w') as f:
                f.write(randomname.randomtopicname(ui))
        return orig(ui, repo, *args, **opts)

def committextwrap(orig, repo, ctx, subs, extramsg):
    ret = orig(repo, ctx, subs, extramsg)
    if hastopicext(repo):
        t = repo.currenttopic
        if t:
            ret = ret.replace(b"\nHG: branch",
                              b"\nHG: topic '%s'\nHG: branch" % t)
    return ret

def pushoutgoingwrap(orig, ui, repo, *args, **opts):
    if opts.get('topic'):
        topicrevs = repo.revs(b'topic(%s) - obsolete()', opts['topic'])
        opts.setdefault('rev', []).extend(topicrevs)
    return orig(ui, repo, *args, **opts)

def mergeupdatewrap(orig, repo, node, branchmerge, force, *args, **kwargs):
    matcher = kwargs.get('matcher')

        # current topic. This is right for merge but wrong for rebase. We check
        # if rebase is running and update the currenttopic to topic of new
        # rebased commit. We have explicitly stored in config if rebase is
        # running.
        ot = repo.currenttopic
        if repo.ui.hasconfig(b'experimental', b'topicrebase'):
            isrebase = True
        if repo.ui.configbool(b'_internal', b'keep-topic'):
            ist0 = True
        if ((not partial and not branchmerge) or isrebase) and not ist0:
            t = b''
            pctx = repo[node]
            if pctx.phase() > phases.public:
                t = pctx.topic()
            with repo.vfs.open(b'topic', b'w') as f:
                f.write(t)
            if t and t != ot:
                repo.ui.status(_(b"switching to topic %s\n") % t)
            if ot and not t:
                st = stack.stack(repo, topic=ot)
                if not st:
                    repo.ui.status(_(b'clearing empty topic "%s"\n') % ot)
        elif ist0:
            repo.ui.status(_(b"preserving the current topic '%s'\n") % ot)
        return ret
    finally:
        wlock.release()

def checkt0(orig, ui, repo, node=None, rev=None, *args, **kwargs):

    thezeros = set([b't0', b'b0', b's0'])
    backup = repo.ui.backupconfig(b'_internal', b'keep-topic')
    try:
        if node in thezeros or rev in thezeros:
            repo.ui.setconfig(b'_internal', b'keep-topic', b'yes',
                              source=b'topic-extension')
        return orig(ui, repo, node=node, rev=rev, *args, **kwargs)
    finally:
        repo.ui.restoreconfig(backup)

def _fixrebase(loaded):

    def savetopic(ctx, extra):
        if ctx.topic():
            extra[constants.extrakey] = ctx.topic()

    def setrebaseconfig(orig, ui, repo, **opts):
        repo.ui.setconfig(b'experimental', b'topicrebase', b'yes',
                          source=b'topic-extension')
        return orig(ui, repo, **opts)

    def new_init(orig, *args, **kwargs):
        runtime = orig(*args, **kwargs)

            runtime.extrafns.append(savetopic)

        return runtime

    try:
        rebase = extensions.find(b"rebase")
        extensions.wrapfunction(rebase.rebaseruntime, '__init__', new_init)
        # This exists to store in the config that rebase is running so that we can
        # update the topic according to rebase. This is a hack and should be removed
        # when we have better options.
        extensions.wrapcommand(rebase.cmdtable, b'rebase', setrebaseconfig)
    except KeyError:
        pass

## preserve topic during import/export

def _exporttopic(seq, ctx):
    topic = ctx.topic()
    if topic:
        return b'EXP-Topic %s' % topic
    return None

def _importtopic(repo, patchdata, extra, opts):
    if b'topic' in patchdata:
        extra[b'topic'] = patchdata[b'topic']

def setupimportexport(ui):
    """run at ui setup time to install import/export logic"""
    cmdutil.extraexport.append(b'topic')
    cmdutil.extraexportmap[b'topic'] = _exporttopic
    cmdutil.extrapreimport.append(b'topic')
    cmdutil.extrapreimportmap[b'topic'] = _importtopic
    patch.patchheadermap.append((b'EXP-Topic', b'topic'))

## preserve topic during split

def presplitupdatetopic(original, repo, ui, prev, ctx):
    # Save topic of revision