view hgext/transplant.py @ 42044:bb271ec2fbfb

compression: introduce a `storage.revlog.zstd.level` configuration This option control the zstd compression level used when compressing revlog chunk. The usage of zstd for revlog compression has not graduated from experimental yet, but we intend to fix that soon. The option name for the compression level is more straight forward to pick, so this changesets comes first. Having a dedicated option for each compression engine is useful because they don't support the same range of values. I ran the same measurement as for the zlib compression level (in the parent changesets). The variation in repository size is stay mostly in the same (small) range. The "read/write" performance see smallish variation, but are overall much better than zlib. Write performance show the same tend of having better write performance for when reaching high-end compression. Again, we don't intend to change the default zstd compression level (currently: 3) in this series. However this is worth investigating in the future. The Performance comparison of zlib vs zstd is quite impressive. The repository size stay in the same range, but the performance are much better in all situations. Comparison summary ================== We are looking at: - performance range for zlib - performance range for zstd - comparison of default zstd (level-3) to default zlib (level 6) - comparison of the slowest zstd time to the fastest zlib time Read performance: ----------------- | zlib | zstd | cmp | f2s mercurial | 0.170159 - 0.189219 | 0.144127 - 0.149624 | 80% | 88% pypy | 2.679217 - 2.768691 | 1.532317 - 1.705044 | 60% | 63% netbeans | 122.477027 - 141.620281 | 72.996346 - 89.731560 | 58% | 73% mozilla | 147.867662 - 170.572118 | 91.700995 - 105.853099 | 56% | 71% Write performance: ------------------ | zlib | zstd | cmp | f2s mercurial | 53.250304 - 56.2936129 | 40.877025 - 45.677286 | 75% | 86% pypy | 460.721984 - 476.589918 | 270.545409 - 301.002219 | 63% | 65% netbeans | 520.560316 - 715.930400 | 370.356311 - 428.329652 | 55% | 82% mozilla | 739.803002 - 987.056093 | 505.152906 - 591.930683 | 57% | 80% Raw data -------- repo alg lvl .hg/store size 00manifest.d read write mercurial zlib 1 49,402,813 5,963,475 0.170159 53.250304 mercurial zlib 6 47,197,397 5,875,730 0.182820 56.264320 mercurial zlib 9 47,121,596 5,849,781 0.189219 56.293612 mercurial zstd 1 49,737,084 5,966,355 0.144127 40.877025 mercurial zstd 3 48,961,867 5,895,208 0.146376 42.268142 mercurial zstd 5 48,200,592 5,938,676 0.149624 43.162875 mercurial zstd 10 47,833,520 5,913,353 0.145185 44.012489 mercurial zstd 15 47,314,604 5,728,679 0.147686 45.677286 mercurial zstd 20 47,330,502 5,830,539 0.145789 45.025407 mercurial zstd 22 47,330,076 5,830,539 0.143996 44.690460 pypy zlib 1 370,830,572 28,462,425 2.679217 460.721984 pypy zlib 6 340,112,317 27,648,747 2.768691 467.537158 pypy zlib 9 338,360,736 27,639,003 2.763495 476.589918 pypy zstd 1 362,377,479 27,916,214 1.532317 270.545409 pypy zstd 3 354,137,693 27,905,988 1.686718 294.951509 pypy zstd 5 342,640,043 27,655,774 1.705044 301.002219 pypy zstd 10 334,224,327 27,164,493 1.567287 285.186239 pypy zstd 15 329,000,363 26,645,965 1.637729 299.561332 pypy zstd 20 324,534,039 26,199,547 1.526813 302.149827 pypy zstd 22 324,530,595 26,198,932 1.525718 307.821218 netbeans zlib 1 1,281,847,810 165,495,457 122.477027 520.560316 netbeans zlib 6 1,205,284,353 159,161,207 139.876147 715.930400 netbeans zlib 9 1,197,135,671 155,034,586 141.620281 678.297064 netbeans zstd 1 1,259,581,737 160,840,613 72.996346 370.356311 netbeans zstd 3 1,232,978,122 157,691,551 81.622317 396.733087 netbeans zstd 5 1,208,034,075 160,246,880 83.080549 364.342626 netbeans zstd 10 1,188,624,176 156,083,417 79.323935 403.594602 netbeans zstd 15 1,176,973,589 153,859,477 89.731560 428.329652 netbeans zstd 20 1,162,958,258 151,147,535 82.842667 392.335349 netbeans zstd 22 1,162,707,029 151,150,220 82.565695 402.840655 mozilla zlib 1 2,775,497,186 298,527,987 147.867662 751.263721 mozilla zlib 6 2,596,856,420 286,597,671 170.572118 987.056093 mozilla zlib 9 2,587,542,494 287,018,264 163.622338 739.803002 mozilla zstd 1 2,723,159,348 286,617,532 91.700995 570.042751 mozilla zstd 3 2,665,055,001 286,152,013 95.240155 561.412805 mozilla zstd 5 2,607,819,817 288,060,030 101.978048 505.152906 mozilla zstd 10 2,558,761,085 283,967,648 104.113481 497.771202 mozilla zstd 15 2,526,216,060 275,581,300 105.853099 591.930683 mozilla zstd 20 2,485,114,806 266,478,859 95.268795 576.515389 mozilla zstd 22 2,484,869,080 266,456,505 94.429282 572.785537
author Pierre-Yves David <pierre-yves.david@octobus.net>
date Wed, 27 Mar 2019 18:35:59 +0100
parents 0531dff73d0b
children 5f2f6912c9e6
line wrap: on
line source

# Patch transplanting extension for Mercurial
#
# Copyright 2006, 2007 Brendan Cully <brendan@kublai.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

'''command to transplant changesets from another branch

This extension allows you to transplant changes to another parent revision,
possibly in another repository. The transplant is done using 'diff' patches.

Transplanted patches are recorded in .hg/transplant/transplants, as a
map from a changeset hash to its hash in the source repository.
'''
from __future__ import absolute_import

import os

from mercurial.i18n import _
from mercurial import (
    bundlerepo,
    cmdutil,
    error,
    exchange,
    hg,
    logcmdutil,
    match,
    merge,
    node as nodemod,
    patch,
    pycompat,
    registrar,
    revlog,
    revset,
    scmutil,
    smartset,
    util,
    vfs as vfsmod,
)
from mercurial.utils import (
    procutil,
    stringutil,
)

class TransplantError(error.Abort):
    pass

cmdtable = {}
command = registrar.command(cmdtable)
# Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for
# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
# be specifying the version(s) of Mercurial they are tested with, or
# leave the attribute unspecified.
testedwith = 'ships-with-hg-core'

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

configitem('transplant', 'filter',
    default=None,
)
configitem('transplant', 'log',
    default=None,
)

class transplantentry(object):
    def __init__(self, lnode, rnode):
        self.lnode = lnode
        self.rnode = rnode

class transplants(object):
    def __init__(self, path=None, transplantfile=None, opener=None):
        self.path = path
        self.transplantfile = transplantfile
        self.opener = opener

        if not opener:
            self.opener = vfsmod.vfs(self.path)
        self.transplants = {}
        self.dirty = False
        self.read()

    def read(self):
        abspath = os.path.join(self.path, self.transplantfile)
        if self.transplantfile and os.path.exists(abspath):
            for line in self.opener.read(self.transplantfile).splitlines():
                lnode, rnode = map(revlog.bin, line.split(':'))
                list = self.transplants.setdefault(rnode, [])
                list.append(transplantentry(lnode, rnode))

    def write(self):
        if self.dirty and self.transplantfile:
            if not os.path.isdir(self.path):
                os.mkdir(self.path)
            fp = self.opener(self.transplantfile, 'w')
            for list in self.transplants.itervalues():
                for t in list:
                    l, r = map(nodemod.hex, (t.lnode, t.rnode))
                    fp.write(l + ':' + r + '\n')
            fp.close()
        self.dirty = False

    def get(self, rnode):
        return self.transplants.get(rnode) or []

    def set(self, lnode, rnode):
        list = self.transplants.setdefault(rnode, [])
        list.append(transplantentry(lnode, rnode))
        self.dirty = True

    def remove(self, transplant):
        list = self.transplants.get(transplant.rnode)
        if list:
            del list[list.index(transplant)]
            self.dirty = True

class transplanter(object):
    def __init__(self, ui, repo, opts):
        self.ui = ui
        self.path = repo.vfs.join('transplant')
        self.opener = vfsmod.vfs(self.path)
        self.transplants = transplants(self.path, 'transplants',
                                       opener=self.opener)
        def getcommiteditor():
            editform = cmdutil.mergeeditform(repo[None], 'transplant')
            return cmdutil.getcommiteditor(editform=editform,
                                           **pycompat.strkwargs(opts))
        self.getcommiteditor = getcommiteditor

    def applied(self, repo, node, parent):
        '''returns True if a node is already an ancestor of parent
        or is parent or has already been transplanted'''
        if hasnode(repo, parent):
            parentrev = repo.changelog.rev(parent)
        if hasnode(repo, node):
            rev = repo.changelog.rev(node)
            reachable = repo.changelog.ancestors([parentrev], rev,
                                                 inclusive=True)
            if rev in reachable:
                return True
        for t in self.transplants.get(node):
            # it might have been stripped
            if not hasnode(repo, t.lnode):
                self.transplants.remove(t)
                return False
            lnoderev = repo.changelog.rev(t.lnode)
            if lnoderev in repo.changelog.ancestors([parentrev], lnoderev,
                                                    inclusive=True):
                return True
        return False

    def apply(self, repo, source, revmap, merges, opts=None):
        '''apply the revisions in revmap one by one in revision order'''
        if opts is None:
            opts = {}
        revs = sorted(revmap)
        p1 = repo.dirstate.p1()
        pulls = []
        diffopts = patch.difffeatureopts(self.ui, opts)
        diffopts.git = True

        lock = tr = None
        try:
            lock = repo.lock()
            tr = repo.transaction('transplant')
            for rev in revs:
                node = revmap[rev]
                revstr = '%d:%s' % (rev, nodemod.short(node))

                if self.applied(repo, node, p1):
                    self.ui.warn(_('skipping already applied revision %s\n') %
                                 revstr)
                    continue

                parents = source.changelog.parents(node)
                if not (opts.get('filter') or opts.get('log')):
                    # If the changeset parent is the same as the
                    # wdir's parent, just pull it.
                    if parents[0] == p1:
                        pulls.append(node)
                        p1 = node
                        continue
                    if pulls:
                        if source != repo:
                            exchange.pull(repo, source.peer(), heads=pulls)
                        merge.update(repo, pulls[-1], branchmerge=False,
                                     force=False)
                        p1 = repo.dirstate.p1()
                        pulls = []

                domerge = False
                if node in merges:
                    # pulling all the merge revs at once would mean we
                    # couldn't transplant after the latest even if
                    # transplants before them fail.
                    domerge = True
                    if not hasnode(repo, node):
                        exchange.pull(repo, source.peer(), heads=[node])

                skipmerge = False
                if parents[1] != revlog.nullid:
                    if not opts.get('parent'):
                        self.ui.note(_('skipping merge changeset %d:%s\n')
                                     % (rev, nodemod.short(node)))
                        skipmerge = True
                    else:
                        parent = source.lookup(opts['parent'])
                        if parent not in parents:
                            raise error.Abort(_('%s is not a parent of %s') %
                                              (nodemod.short(parent),
                                               nodemod.short(node)))
                else:
                    parent = parents[0]

                if skipmerge:
                    patchfile = None
                else:
                    fd, patchfile = pycompat.mkstemp(prefix='hg-transplant-')
                    fp = os.fdopen(fd, r'wb')
                    gen = patch.diff(source, parent, node, opts=diffopts)
                    for chunk in gen:
                        fp.write(chunk)
                    fp.close()

                del revmap[rev]
                if patchfile or domerge:
                    try:
                        try:
                            n = self.applyone(repo, node,
                                              source.changelog.read(node),
                                              patchfile, merge=domerge,
                                              log=opts.get('log'),
                                              filter=opts.get('filter'))
                        except TransplantError:
                            # Do not rollback, it is up to the user to
                            # fix the merge or cancel everything
                            tr.close()
                            raise
                        if n and domerge:
                            self.ui.status(_('%s merged at %s\n') % (revstr,
                                      nodemod.short(n)))
                        elif n:
                            self.ui.status(_('%s transplanted to %s\n')
                                           % (nodemod.short(node),
                                              nodemod.short(n)))
                    finally:
                        if patchfile:
                            os.unlink(patchfile)
            tr.close()
            if pulls:
                exchange.pull(repo, source.peer(), heads=pulls)
                merge.update(repo, pulls[-1], branchmerge=False, force=False)
        finally:
            self.saveseries(revmap, merges)
            self.transplants.write()
            if tr:
                tr.release()
            if lock:
                lock.release()

    def filter(self, filter, node, changelog, patchfile):
        '''arbitrarily rewrite changeset before applying it'''

        self.ui.status(_('filtering %s\n') % patchfile)
        user, date, msg = (changelog[1], changelog[2], changelog[4])
        fd, headerfile = pycompat.mkstemp(prefix='hg-transplant-')
        fp = os.fdopen(fd, r'wb')
        fp.write("# HG changeset patch\n")
        fp.write("# User %s\n" % user)
        fp.write("# Date %d %d\n" % date)
        fp.write(msg + '\n')
        fp.close()

        try:
            self.ui.system('%s %s %s' % (filter,
                                         procutil.shellquote(headerfile),
                                         procutil.shellquote(patchfile)),
                           environ={'HGUSER': changelog[1],
                                    'HGREVISION': nodemod.hex(node),
                                    },
                           onerr=error.Abort, errprefix=_('filter failed'),
                           blockedtag='transplant_filter')
            user, date, msg = self.parselog(open(headerfile, 'rb'))[1:4]
        finally:
            os.unlink(headerfile)

        return (user, date, msg)

    def applyone(self, repo, node, cl, patchfile, merge=False, log=False,
                 filter=None):
        '''apply the patch in patchfile to the repository as a transplant'''
        (manifest, user, (time, timezone), files, message) = cl[:5]
        date = "%d %d" % (time, timezone)
        extra = {'transplant_source': node}
        if filter:
            (user, date, message) = self.filter(filter, node, cl, patchfile)

        if log:
            # we don't translate messages inserted into commits
            message += '\n(transplanted from %s)' % nodemod.hex(node)

        self.ui.status(_('applying %s\n') % nodemod.short(node))
        self.ui.note('%s %s\n%s\n' % (user, date, message))

        if not patchfile and not merge:
            raise error.Abort(_('can only omit patchfile if merging'))
        if patchfile:
            try:
                files = set()
                patch.patch(self.ui, repo, patchfile, files=files, eolmode=None)
                files = list(files)
            except Exception as inst:
                seriespath = os.path.join(self.path, 'series')
                if os.path.exists(seriespath):
                    os.unlink(seriespath)
                p1 = repo.dirstate.p1()
                p2 = node
                self.log(user, date, message, p1, p2, merge=merge)
                self.ui.write(stringutil.forcebytestr(inst) + '\n')
                raise TransplantError(_('fix up the working directory and run '
                                        'hg transplant --continue'))
        else:
            files = None
        if merge:
            p1 = repo.dirstate.p1()
            repo.setparents(p1, node)
            m = match.always()
        else:
            m = match.exact(files)

        n = repo.commit(message, user, date, extra=extra, match=m,
                        editor=self.getcommiteditor())
        if not n:
            self.ui.warn(_('skipping emptied changeset %s\n') %
                           nodemod.short(node))
            return None
        if not merge:
            self.transplants.set(n, node)

        return n

    def canresume(self):
        return os.path.exists(os.path.join(self.path, 'journal'))

    def resume(self, repo, source, opts):
        '''recover last transaction and apply remaining changesets'''
        if os.path.exists(os.path.join(self.path, 'journal')):
            n, node = self.recover(repo, source, opts)
            if n:
                self.ui.status(_('%s transplanted as %s\n') %
                                 (nodemod.short(node),
                                  nodemod.short(n)))
            else:
                self.ui.status(_('%s skipped due to empty diff\n')
                               % (nodemod.short(node),))
        seriespath = os.path.join(self.path, 'series')
        if not os.path.exists(seriespath):
            self.transplants.write()
            return
        nodes, merges = self.readseries()
        revmap = {}
        for n in nodes:
            revmap[source.changelog.rev(n)] = n
        os.unlink(seriespath)

        self.apply(repo, source, revmap, merges, opts)

    def recover(self, repo, source, opts):
        '''commit working directory using journal metadata'''
        node, user, date, message, parents = self.readlog()
        merge = False

        if not user or not date or not message or not parents[0]:
            raise error.Abort(_('transplant log file is corrupt'))

        parent = parents[0]
        if len(parents) > 1:
            if opts.get('parent'):
                parent = source.lookup(opts['parent'])
                if parent not in parents:
                    raise error.Abort(_('%s is not a parent of %s') %
                                      (nodemod.short(parent),
                                       nodemod.short(node)))
            else:
                merge = True

        extra = {'transplant_source': node}
        try:
            p1 = repo.dirstate.p1()
            if p1 != parent:
                raise error.Abort(_('working directory not at transplant '
                                   'parent %s') % nodemod.hex(parent))
            if merge:
                repo.setparents(p1, parents[1])
            modified, added, removed, deleted = repo.status()[:4]
            if merge or modified or added or removed or deleted:
                n = repo.commit(message, user, date, extra=extra,
                                editor=self.getcommiteditor())
                if not n:
                    raise error.Abort(_('commit failed'))
                if not merge:
                    self.transplants.set(n, node)
            else:
                n = None
            self.unlog()

            return n, node
        finally:
            # TODO: get rid of this meaningless try/finally enclosing.
            # this is kept only to reduce changes in a patch.
            pass

    def readseries(self):
        nodes = []
        merges = []
        cur = nodes
        for line in self.opener.read('series').splitlines():
            if line.startswith('# Merges'):
                cur = merges
                continue
            cur.append(revlog.bin(line))

        return (nodes, merges)

    def saveseries(self, revmap, merges):
        if not revmap:
            return

        if not os.path.isdir(self.path):
            os.mkdir(self.path)
        series = self.opener('series', 'w')
        for rev in sorted(revmap):
            series.write(nodemod.hex(revmap[rev]) + '\n')
        if merges:
            series.write('# Merges\n')
            for m in merges:
                series.write(nodemod.hex(m) + '\n')
        series.close()

    def parselog(self, fp):
        parents = []
        message = []
        node = revlog.nullid
        inmsg = False
        user = None
        date = None
        for line in fp.read().splitlines():
            if inmsg:
                message.append(line)
            elif line.startswith('# User '):
                user = line[7:]
            elif line.startswith('# Date '):
                date = line[7:]
            elif line.startswith('# Node ID '):
                node = revlog.bin(line[10:])
            elif line.startswith('# Parent '):
                parents.append(revlog.bin(line[9:]))
            elif not line.startswith('# '):
                inmsg = True
                message.append(line)
        if None in (user, date):
            raise error.Abort(_("filter corrupted changeset (no user or date)"))
        return (node, user, date, '\n'.join(message), parents)

    def log(self, user, date, message, p1, p2, merge=False):
        '''journal changelog metadata for later recover'''

        if not os.path.isdir(self.path):
            os.mkdir(self.path)
        fp = self.opener('journal', 'w')
        fp.write('# User %s\n' % user)
        fp.write('# Date %s\n' % date)
        fp.write('# Node ID %s\n' % nodemod.hex(p2))
        fp.write('# Parent ' + nodemod.hex(p1) + '\n')
        if merge:
            fp.write('# Parent ' + nodemod.hex(p2) + '\n')
        fp.write(message.rstrip() + '\n')
        fp.close()

    def readlog(self):
        return self.parselog(self.opener('journal'))

    def unlog(self):
        '''remove changelog journal'''
        absdst = os.path.join(self.path, 'journal')
        if os.path.exists(absdst):
            os.unlink(absdst)

    def transplantfilter(self, repo, source, root):
        def matchfn(node):
            if self.applied(repo, node, root):
                return False
            if source.changelog.parents(node)[1] != revlog.nullid:
                return False
            extra = source.changelog.read(node)[5]
            cnode = extra.get('transplant_source')
            if cnode and self.applied(repo, cnode, root):
                return False
            return True

        return matchfn

def hasnode(repo, node):
    try:
        return repo.changelog.rev(node) is not None
    except error.StorageError:
        return False

def browserevs(ui, repo, nodes, opts):
    '''interactively transplant changesets'''
    displayer = logcmdutil.changesetdisplayer(ui, repo, opts)
    transplants = []
    merges = []
    prompt = _('apply changeset? [ynmpcq?]:'
               '$$ &yes, transplant this changeset'
               '$$ &no, skip this changeset'
               '$$ &merge at this changeset'
               '$$ show &patch'
               '$$ &commit selected changesets'
               '$$ &quit and cancel transplant'
               '$$ &? (show this help)')
    for node in nodes:
        displayer.show(repo[node])
        action = None
        while not action:
            choice = ui.promptchoice(prompt)
            action = 'ynmpcq?'[choice:choice + 1]
            if action == '?':
                for c, t in ui.extractchoices(prompt)[1]:
                    ui.write('%s: %s\n' % (c, t))
                action = None
            elif action == 'p':
                parent = repo.changelog.parents(node)[0]
                for chunk in patch.diff(repo, parent, node):
                    ui.write(chunk)
                action = None
        if action == 'y':
            transplants.append(node)
        elif action == 'm':
            merges.append(node)
        elif action == 'c':
            break
        elif action == 'q':
            transplants = ()
            merges = ()
            break
    displayer.close()
    return (transplants, merges)

@command('transplant',
    [('s', 'source', '', _('transplant changesets from REPO'), _('REPO')),
    ('b', 'branch', [], _('use this source changeset as head'), _('REV')),
    ('a', 'all', None, _('pull all changesets up to the --branch revisions')),
    ('p', 'prune', [], _('skip over REV'), _('REV')),
    ('m', 'merge', [], _('merge at REV'), _('REV')),
    ('', 'parent', '',
     _('parent to choose when transplanting merge'), _('REV')),
    ('e', 'edit', False, _('invoke editor on commit messages')),
    ('', 'log', None, _('append transplant info to log message')),
    ('c', 'continue', None, _('continue last transplant session '
                              'after fixing conflicts')),
    ('', 'filter', '',
     _('filter changesets through command'), _('CMD'))],
    _('hg transplant [-s REPO] [-b BRANCH [-a]] [-p REV] '
      '[-m REV] [REV]...'),
    helpcategory=command.CATEGORY_CHANGE_MANAGEMENT)
def transplant(ui, repo, *revs, **opts):
    '''transplant changesets from another branch

    Selected changesets will be applied on top of the current working
    directory with the log of the original changeset. The changesets
    are copied and will thus appear twice in the history with different
    identities.

    Consider using the graft command if everything is inside the same
    repository - it will use merges and will usually give a better result.
    Use the rebase extension if the changesets are unpublished and you want
    to move them instead of copying them.

    If --log is specified, log messages will have a comment appended
    of the form::

      (transplanted from CHANGESETHASH)

    You can rewrite the changelog message with the --filter option.
    Its argument will be invoked with the current changelog message as
    $1 and the patch as $2.

    --source/-s specifies another repository to use for selecting changesets,
    just as if it temporarily had been pulled.
    If --branch/-b is specified, these revisions will be used as
    heads when deciding which changesets to transplant, just as if only
    these revisions had been pulled.
    If --all/-a is specified, all the revisions up to the heads specified
    with --branch will be transplanted.

    Example:

    - transplant all changes up to REV on top of your current revision::

        hg transplant --branch REV --all

    You can optionally mark selected transplanted changesets as merge
    changesets. You will not be prompted to transplant any ancestors
    of a merged transplant, and you can merge descendants of them
    normally instead of transplanting them.

    Merge changesets may be transplanted directly by specifying the
    proper parent changeset by calling :hg:`transplant --parent`.

    If no merges or revisions are provided, :hg:`transplant` will
    start an interactive changeset browser.

    If a changeset application fails, you can fix the merge by hand
    and then resume where you left off by calling :hg:`transplant
    --continue/-c`.
    '''
    with repo.wlock():
        return _dotransplant(ui, repo, *revs, **opts)

def _dotransplant(ui, repo, *revs, **opts):
    def incwalk(repo, csets, match=util.always):
        for node in csets:
            if match(node):
                yield node

    def transplantwalk(repo, dest, heads, match=util.always):
        '''Yield all nodes that are ancestors of a head but not ancestors
        of dest.
        If no heads are specified, the heads of repo will be used.'''
        if not heads:
            heads = repo.heads()
        ancestors = []
        ctx = repo[dest]
        for head in heads:
            ancestors.append(ctx.ancestor(repo[head]).node())
        for node in repo.changelog.nodesbetween(ancestors, heads)[0]:
            if match(node):
                yield node

    def checkopts(opts, revs):
        if opts.get('continue'):
            if opts.get('branch') or opts.get('all') or opts.get('merge'):
                raise error.Abort(_('--continue is incompatible with '
                                   '--branch, --all and --merge'))
            return
        if not (opts.get('source') or revs or
                opts.get('merge') or opts.get('branch')):
            raise error.Abort(_('no source URL, branch revision, or revision '
                               'list provided'))
        if opts.get('all'):
            if not opts.get('branch'):
                raise error.Abort(_('--all requires a branch revision'))
            if revs:
                raise error.Abort(_('--all is incompatible with a '
                                   'revision list'))

    opts = pycompat.byteskwargs(opts)
    checkopts(opts, revs)

    if not opts.get('log'):
        # deprecated config: transplant.log
        opts['log'] = ui.config('transplant', 'log')
    if not opts.get('filter'):
        # deprecated config: transplant.filter
        opts['filter'] = ui.config('transplant', 'filter')

    tp = transplanter(ui, repo, opts)

    p1 = repo.dirstate.p1()
    if len(repo) > 0 and p1 == revlog.nullid:
        raise error.Abort(_('no revision checked out'))
    if opts.get('continue'):
        if not tp.canresume():
            raise error.Abort(_('no transplant to continue'))
    else:
        cmdutil.checkunfinished(repo)
        cmdutil.bailifchanged(repo)

    sourcerepo = opts.get('source')
    if sourcerepo:
        peer = hg.peer(repo, opts, ui.expandpath(sourcerepo))
        heads = pycompat.maplist(peer.lookup, opts.get('branch', ()))
        target = set(heads)
        for r in revs:
            try:
                target.add(peer.lookup(r))
            except error.RepoError:
                pass
        source, csets, cleanupfn = bundlerepo.getremotechanges(ui, repo, peer,
                                    onlyheads=sorted(target), force=True)
    else:
        source = repo
        heads = pycompat.maplist(source.lookup, opts.get('branch', ()))
        cleanupfn = None

    try:
        if opts.get('continue'):
            tp.resume(repo, source, opts)
            return

        tf = tp.transplantfilter(repo, source, p1)
        if opts.get('prune'):
            prune = set(source[r].node()
                        for r in scmutil.revrange(source, opts.get('prune')))
            matchfn = lambda x: tf(x) and x not in prune
        else:
            matchfn = tf
        merges = pycompat.maplist(source.lookup, opts.get('merge', ()))
        revmap = {}
        if revs:
            for r in scmutil.revrange(source, revs):
                revmap[int(r)] = source[r].node()
        elif opts.get('all') or not merges:
            if source != repo:
                alltransplants = incwalk(source, csets, match=matchfn)
            else:
                alltransplants = transplantwalk(source, p1, heads,
                                                match=matchfn)
            if opts.get('all'):
                revs = alltransplants
            else:
                revs, newmerges = browserevs(ui, source, alltransplants, opts)
                merges.extend(newmerges)
            for r in revs:
                revmap[source.changelog.rev(r)] = r
        for r in merges:
            revmap[source.changelog.rev(r)] = r

        tp.apply(repo, source, revmap, merges, opts)
    finally:
        if cleanupfn:
            cleanupfn()

revsetpredicate = registrar.revsetpredicate()

@revsetpredicate('transplanted([set])')
def revsettransplanted(repo, subset, x):
    """Transplanted changesets in set, or all transplanted changesets.
    """
    if x:
        s = revset.getset(repo, subset, x)
    else:
        s = subset
    return smartset.baseset([r for r in s if
        repo[r].extra().get('transplant_source')])

templatekeyword = registrar.templatekeyword()

@templatekeyword('transplanted', requires={'ctx'})
def kwtransplanted(context, mapping):
    """String. The node identifier of the transplanted
    changeset if any."""
    ctx = context.resource(mapping, 'ctx')
    n = ctx.extra().get('transplant_source')
    return n and nodemod.hex(n) or ''

def extsetup(ui):
    cmdutil.unfinishedstates.append(
        ['transplant/journal', True, False, _('transplant in progress'),
         _("use 'hg transplant --continue' or 'hg update' to abort")])

# tell hggettext to extract docstrings from these functions:
i18nfunctions = [revsettransplanted, kwtransplanted]