comparison hgext/rebase.py @ 43076:2372284d9457

formatting: blacken the codebase

This is using my patch to black
(https://github.com/psf/black/pull/826) so we don't un-wrap collection
literals.

Done with:

  hg files 'set:**.py - mercurial/thirdparty/** - "contrib/python-zstandard/**"' | xargs black -S

# skip-blame mass-reformatting only

# no-check-commit reformats foo_bar functions

Differential Revision: https://phab.mercurial-scm.org/D6971

43075:57875cf423c9

# 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'

def _nothingtorebase():
    return 1

def _savegraft(ctx, extra):
    s = ctx.extra().get('source', None)
    if s is not None:
        extra['source'] = s
    s = ctx.extra().get('intermediate-source', None)
    if s is not None:
        extra['intermediate-source'] = s

def _savebranch(ctx, extra):
    extra['branch'] = ctx.branch()

def _destrebase(repo, sourceset, destspace=None):
    """small wrapper around destmerge to pass the right extra args

    Please wrap destutil.destmerge instead."""
    return destutil.destmerge(repo, action='rebase', sourceset=sourceset,
                              onheadcheck=False, destspace=destspace)

revsetpredicate = registrar.revsetpredicate()

@revsetpredicate('_destrebase')
def _revsetdestrebase(repo, subset, x):
    # ``_rebasedefaultdest()``

    sourceset = None
    if x is not None:
        sourceset = revset.getset(repo, smartset.fullreposet(repo), x)
    return subset & smartset.baseset([_destrebase(repo, sourceset)])

@revsetpredicate('_destautoorphanrebase')
def _revsetdestautoorphanrebase(repo, subset, x):
    # ``_destautoorphanrebase()``

    # automatic rebase destination for a single orphan revision.

    if not src or src in obsoleted:
        return smartset.baseset()
    dests = destutil.orphanpossibledestination(repo, src)
    if len(dests) > 1:
        raise error.Abort(
            _("ambiguous automatic rebase: %r could end up on any of %r") % (
                src, dests))
    # We have zero or one destination, so we can just return here.
    return smartset.baseset(dests)

def _ctxdesc(ctx):
    """short description for a context"""
    desc = '%d:%s "%s"' % (ctx.rev(), ctx,
                           ctx.description().split('\n', 1)[0])
    repo = ctx.repo()
    names = []
    for nsname, ns in repo.names.iteritems():
        if nsname == 'branches':
            continue
        names.extend(ns.names(repo, ctx.node()))
    if names:
        desc += ' (%s)' % ' '.join(names)
    return desc

class rebaseruntime(object):
    """This class is a container for rebase runtime state"""
    def __init__(self, repo, ui, inmemory=False, opts=None):
        if opts is None:
            opts = {}

        # prepared: whether we have rebasestate prepared or not. Currently it

        self.collapsef = opts.get('collapse', False)
        self.collapsemsg = cmdutil.logmessage(ui, opts)
        self.date = opts.get('date', None)

        e = opts.get('extrafn') # internal, used by e.g. hgsubversion
        self.extrafns = [_savegraft]
        if e:
            self.extrafns = [e]

        self.backupf = ui.configbool('rewrite', 'backup-bundle')

            return self._repo

    def storestatus(self, tr=None):
        """Store the current status to allow recovery"""
        if tr:
            tr.addfilegenerator('rebasestate', ('rebasestate',),
                                self._writestatus, location='plain')
        else:
            with self.repo.vfs("rebasestate", "w") as f:
                self._writestatus(f)

    def _writestatus(self, f):

    def _read(self):
        self.prepared = True
        repo = self.repo
        assert repo.filtername is None
        data = {'keepbranches': None, 'collapse': None, 'activebookmark': None,
                'external': nullrev, 'keep': None, 'originalwd': None}
        legacydest = None
        state = {}
        destmap = {}

        if True:

            for old, new in sorted(state.items()):
                if new != revtodo and new in seen:
                    skipped.add(old)
                seen.add(new)
        data['skipped'] = skipped
        repo.ui.debug('computed skipped revs: %s\n' %
                        (' '.join('%d' % r for r in sorted(skipped)) or ''))

        return data

    def _handleskippingobsolete(self, obsoleterevs, destmap):
        """Compute structures necessary for skipping obsolete revisions

        """
        self.obsoletenotrebased = {}
        if not self.ui.configbool('experimental', 'rebaseskipobsolete'):
            return
        obsoleteset = set(obsoleterevs)
        (self.obsoletenotrebased,
         self.obsoletewithoutsuccessorindestination,
         obsoleteextinctsuccessors) = _computeobsoletenotrebased(
             self.repo, obsoleteset, destmap)
        skippedset = set(self.obsoletenotrebased)
        skippedset.update(self.obsoletewithoutsuccessorindestination)
        skippedset.update(obsoleteextinctsuccessors)
        _checkobsrebase(self.repo, self.ui, obsoleteset, skippedset)

            self.collapsemsg = restorecollapsemsg(self.repo, isabort)
        except error.RepoLookupError:
            if isabort:
                clearstatus(self.repo)
                clearcollapsemsg(self.repo)
                self.repo.ui.warn(_('rebase aborted (no revision is removed,'
                                    ' only broken state is cleared)\n'))
                return 0
            else:
                msg = _('cannot continue inconsistent rebase')
                hint = _('use "hg rebase --abort" to clear broken state')
                raise error.Abort(msg, hint=hint)

        if not destmap:
            return _nothingtorebase()

        rebaseset = destmap.keys()
        allowunstable = obsolete.isenabled(self.repo, obsolete.allowunstableopt)
        if (not (self.keepf or allowunstable)
              and self.repo.revs('first(children(%ld) - %ld)',
                                 rebaseset, rebaseset)):
            raise error.Abort(
                _("can't remove original changesets with"
                  " unrebased descendants"),
                hint=_('use --keep to keep original changesets'))

        result = buildstate(self.repo, destmap, self.collapsef)

        if not result:
            # Empty state built, nothing to rebase
            self.ui.status(_('nothing to rebase\n'))
            return _nothingtorebase()

        for root in self.repo.set('roots(%ld)', rebaseset):
            if not self.keepf and not root.mutable():
                raise error.Abort(_("can't rebase public changeset %s")
                                  % root,
                                  hint=_("see 'hg help phases' for details"))

        (self.originalwd, self.destmap, self.state) = result
        if self.collapsef:
            dests = set(self.destmap.values())
            if len(dests) != 1:
                raise error.Abort(
                    _('--collapse does not work with multiple destinations'))
            destrev = next(iter(dests))
            destancestors = self.repo.changelog.ancestors([destrev],
                                                          inclusive=True)
            self.external = externalparent(self.repo, self.state, destancestors)

        for destrev in sorted(set(destmap.values())):
            dest = self.repo[destrev]
            if dest.closesbranch() and not self.keepbranchesf:

        self.prepared = True

    def _assignworkingcopy(self):
        if self.inmemory:
            from mercurial.context import overlayworkingctx
            self.wctx = overlayworkingctx(self.repo)
            self.repo.ui.debug("rebasing in-memory\n")
        else:
            self.wctx = self.repo[None]
            self.repo.ui.debug("rebasing on disk\n")
        self.repo.ui.log("rebase",
                         "using in-memory rebase: %r\n", self.inmemory,
                         rebase_imm_used=self.inmemory)

    def _performrebase(self, tr):
        self._assignworkingcopy()
        repo, ui = self.repo, self.ui
        if self.keepbranchesf:

            if self.collapsef:
                branches = set()
                for rev in self.state:
                    branches.add(repo[rev].branch())
                    if len(branches) > 1:
                        raise error.Abort(_('cannot collapse multiple named '
                            'branches'))

        # Calculate self.obsoletenotrebased
        obsrevs = _filterobsoleterevs(self.repo, self.state)
        self._handleskippingobsolete(obsrevs, self.destmap)

            # When using single transaction, store state when transaction
            # commits.
            self.storestatus(tr)

        cands = [k for k, v in self.state.iteritems() if v == revtodo]
        p = repo.ui.makeprogress(_("rebasing"), unit=_('changesets'),
                                 total=len(cands))
        def progress(ctx):
            p.increment(item=("%d:%s" % (ctx.rev(), ctx)))
        allowdivergence = self.ui.configbool(
            'experimental', 'evolution.allowdivergence')
        for subset in sortsource(self.destmap):
            sortedrevs = self.repo.revs('sort(%ld, -topo)', subset)
            if not allowdivergence:
                sortedrevs -= self.repo.revs(
                    'descendants(%ld) and not %ld',

        overrides = {('phases', 'new-commit'): destphase}
        if keepbranch:
            overrides[('ui', 'allowemptycommit')] = True
        with repo.ui.configoverride(overrides, 'rebase'):
            if self.inmemory:
                newnode = commitmemorynode(repo, p1, p2,
                    wctx=self.wctx,
                    extra=extra,
                    commitmsg=commitmsg,
                    editor=editor,
                    user=ctx.user(),
                    date=date)
                mergemod.mergestate.clean(repo)
            else:
                newnode = commitnode(repo, p1, p2,
                    extra=extra,
                    commitmsg=commitmsg,
                    editor=editor,
                    user=ctx.user(),
                    date=date)

            if newnode is None:
                # If it ended up being a no-op commit, then the normal
                # merge state clean-up path doesn't happen, so do it
                # here. Fix issue5494

        dest = self.destmap[rev]
        ctx = repo[rev]
        desc = _ctxdesc(ctx)
        if self.state[rev] == rev:
            ui.status(_('already rebased %s\n') % desc)
        elif (not allowdivergence
              and rev in self.obsoletewithoutsuccessorindestination):
            msg = _('note: not rebasing %s and its descendants as '
                    'this would cause divergence\n') % desc
            repo.ui.status(msg)
            self.skipped.add(rev)
        elif rev in self.obsoletenotrebased:
            succ = self.obsoletenotrebased[rev]
            if succ is None:
                msg = _('note: not rebasing %s, it has no '
                        'successor\n') % desc
            else:
                succdesc = _ctxdesc(repo[succ])
                msg = (_('note: not rebasing %s, already in '
                         'destination as %s\n') % (desc, succdesc))
            repo.ui.status(msg)
            # Make clearrebased aware state[rev] is not a true successor
            self.skipped.add(rev)
            # Record rev as moved to its desired destination in self.state.
            # This helps bookmark and working parent movement.
            dest = max(adjustdest(repo, rev, self.destmap, self.state,
                                  self.skipped))
            self.state[rev] = dest
        elif self.state[rev] == revtodo:
            ui.status(_('rebasing %s\n') % desc)
            progressfn(ctx)
            p1, p2, base = defineparents(repo, rev, self.destmap,
                                         self.state, self.skipped,
                                         self.obsoletenotrebased)
            if not self.inmemory and len(repo[None].parents()) == 2:
                repo.ui.debug('resuming interrupted rebase\n')
            else:
                overrides = {('ui', 'forcemerge'): opts.get('tool', '')}
                with ui.configoverride(overrides, 'rebase'):
                    stats = rebasenode(repo, rev, p1, base, self.collapsef,
                                       dest, wctx=self.wctx)
                    if stats.unresolvedcount > 0:
                        if self.inmemory:
                            raise error.InMemoryMergeConflictsError()
                        else:
                            raise error.InterventionRequired(
                                _('unresolved conflicts (see hg '
                                  'resolve, then hg rebase --continue)'))
            if not self.collapsef:
                merging = p2 != nullrev
                editform = cmdutil.mergeeditform(merging, 'rebase')
                editor = cmdutil.getcommiteditor(editform=editform,
                                                 **pycompat.strkwargs(opts))
                newnode = self._concludenode(rev, p1, p2, editor)
            else:
                # Skip commit if we are collapsing
                if self.inmemory:
                    self.wctx.setbase(repo[p1])

            if newnode is not None:
                self.state[rev] = repo[newnode].rev()
                ui.debug('rebased as %s\n' % short(newnode))
            else:
                if not self.collapsef:
                    ui.warn(_('note: not rebasing %s, its destination already '
                              'has all its changes\n') % desc)
                    self.skipped.add(rev)
                self.state[rev] = p1
                ui.debug('next revision set to %d\n' % p1)
        else:
            ui.status(_('already rebased %s as %s\n') %
                      (desc, repo[self.state[rev]]))
        if not tr:
            # When not using single transaction, store state after each
            # commit is completely done. On InterventionRequired, we thus
            # won't store the status. Instead, we'll hit the "len(parents) == 2"
            # case and realize that the commit was in progress.

    def _finishrebase(self):
        repo, ui, opts = self.repo, self.ui, self.opts
        fm = ui.formatter('rebase', opts)
        fm.startitem()
        if self.collapsef:
            p1, p2, _base = defineparents(repo, min(self.state), self.destmap,
                                          self.state, self.skipped,
                                          self.obsoletenotrebased)
            editopt = opts.get('edit')
            editform = 'rebase.collapse'
            if self.collapsemsg:
                commitmsg = self.collapsemsg
            else:

                        commitmsg += '\n* %s' % repo[rebased].description()
                editopt = True
            editor = cmdutil.getcommiteditor(edit=editopt, editform=editform)
            revtoreuse = max(self.state)

            newnode = self._concludenode(revtoreuse, p1, self.external,
                                         editor, commitmsg=commitmsg)

            if newnode is not None:
                newrev = repo[newnode].rev()
                for oldrev in self.state:
                    self.state[oldrev] = newrev

        if 'qtip' in repo.tags():
            updatemq(repo, self.state, self.skipped,
                     **pycompat.strkwargs(opts))

        # restore original working directory
        # (we do this before stripping)
        newwd = self.state.get(self.originalwd, self.originalwd)
        if newwd < 0:

            hg.updaterepo(repo, newwd, overwrite=False)

        collapsedas = None
        if self.collapsef and not self.keepf:
            collapsedas = newnode
        clearrebased(ui, repo, self.destmap, self.state, self.skipped,
                     collapsedas, self.keepf, fm=fm, backup=self.backupf)

        clearstatus(repo)
        clearcollapsemsg(repo)

        ui.note(_("rebase completed\n"))

        if self.skipped:
            skippedlen = len(self.skipped)
            ui.note(_("%d revisions have been skipped\n") % skippedlen)
        fm.end()

        if (self.activebookmark and self.activebookmark in repo._bookmarks and
            repo['.'].node() == repo._bookmarks[self.activebookmark]):
                bookmarks.activate(repo, self.activebookmark)

    def _abort(self, backup=True, suppwarns=False):
        '''Restore the repository to its original state.'''

        repo = self.repo
        try:
            # If the first commits in the rebased set get skipped during the
            # rebase, their values within the state mapping will be the dest
            # rev id. The rebased list must must not contain the dest rev
            # (issue4896)
            rebased = [s for r, s in self.state.items()
                       if s >= 0 and s != r and s != self.destmap[r]]
            immutable = [d for d in rebased if not repo[d].mutable()]
            cleanup = True
            if immutable:
                repo.ui.warn(_("warning: can't clean up public changesets %s\n")
                             % ', '.join(bytes(repo[r]) for r in immutable),
                             hint=_("see 'hg help phases' for details"))
                cleanup = False

            descendants = set()
            if rebased:
                descendants = set(repo.changelog.descendants(rebased))
            if descendants - set(rebased):
                repo.ui.warn(_("warning: new changesets detected on "
                               "destination branch, can't strip\n"))
                cleanup = False

            if cleanup:
                shouldupdate = False
                if rebased:
                    strippoints = [
                        c.node() for c in repo.set('roots(%ld)', rebased)]

                updateifonnodes = set(rebased)
                updateifonnodes.update(self.destmap.values())
                updateifonnodes.add(self.originalwd)
                shouldupdate = repo['.'].rev() in updateifonnodes

                # Update away from the rebase if necessary
                if shouldupdate or needupdate(repo, self.state):
                    mergemod.update(repo, self.originalwd, branchmerge=False,
                                    force=True)

                # Strip from the first rebased revision
                if rebased:
                    repair.strip(repo.ui, repo, strippoints, backup=backup)

            clearcollapsemsg(repo)
            if not suppwarns:
                repo.ui.warn(_('rebase aborted\n'))
        return 0

@command('rebase',
    [('s', 'source', '',
     _('rebase the specified changeset and descendants'), _('REV')),
    ('b', 'base', '',
     _('rebase everything from branching point of specified changeset'),
     _('REV')),
    ('r', 'rev', [],
     _('rebase these revisions'),
     _('REV')),
    ('d', 'dest', '',
     _('rebase onto the specified changeset'), _('REV')),
    ('', 'collapse', False, _('collapse the rebased changesets')),
    ('m', 'message', '',
     _('use text as collapse commit message'), _('TEXT')),
    ('e', 'edit', False, _('invoke editor on commit messages')),
    ('l', 'logfile', '',
     _('read collapse commit message from file'), _('FILE')),
    ('k', 'keep', False, _('keep original changesets')),
    ('', 'keepbranches', False, _('keep original branch names')),
    ('D', 'detach', False, _('(DEPRECATED)')),
    ('i', 'interactive', False, _('(DEPRECATED)')),
    ('t', 'tool', '', _('specify merge tool')),
    ('', 'stop', False, _('stop interrupted rebase')),
    ('c', 'continue', False, _('continue an interrupted rebase')),
    ('a', 'abort', False, _('abort an interrupted rebase')),
    ('', 'auto-orphans', '', _('automatically rebase orphan revisions '
                               'in the specified revset (EXPERIMENTAL)')),
     ] + cmdutil.dryrunopts + cmdutil.formatteropts + cmdutil.confirmopts,
    _('[-s REV | -b REV] [-d REV] [OPTION]'),
    helpcategory=command.CATEGORY_CHANGE_MANAGEMENT)
def rebase(ui, repo, **opts):
    """move changeset (and descendants) to a different branch

    Rebase uses repeated merging to graft changesets from one part of
    history (the source) onto another (the destination). This can be

    inmemory = ui.configbool('rebase', 'experimental.inmemory')
    dryrun = opts.get('dry_run')
    confirm = opts.get('confirm')
    selactions = [k for k in ['abort', 'stop', 'continue'] if opts.get(k)]
    if len(selactions) > 1:
        raise error.Abort(_('cannot use --%s with --%s')
                          % tuple(selactions[:2]))
    action = selactions[0] if selactions else None
    if dryrun and action:
        raise error.Abort(_('cannot specify both --dry-run and --%s') % action)
    if confirm and action:
        raise error.Abort(_('cannot specify both --confirm and --%s') % action)

        inmemory = False

    if opts.get('auto_orphans'):
        for key in opts:
            if key != 'auto_orphans' and opts.get(key):
                raise error.Abort(_('--auto-orphans is incompatible with %s') %
                                  ('--' + key))
        userrevs = list(repo.revs(opts.get('auto_orphans')))
        opts['rev'] = [revsetlang.formatspec('%ld and orphan()', userrevs)]
        opts['dest'] = '_destautoorphanrebase(SRC)'

    if dryrun or confirm:

            rbsrt.restorestatus()
            if rbsrt.collapsef:
                raise error.Abort(_("cannot stop in --collapse session"))
            allowunstable = obsolete.isenabled(repo, obsolete.allowunstableopt)
            if not (rbsrt.keepf or allowunstable):
                raise error.Abort(_("cannot remove original changesets with"
                                    " unrebased descendants"),
                    hint=_('either enable obsmarkers to allow unstable '
                           'revisions or use --keep to keep original '
                           'changesets'))
            if needupdate(repo, rbsrt.state):
                # update to the current working revision
                # to clear interrupted merge
                hg.updaterepo(repo, rbsrt.originalwd, overwrite=True)
            rbsrt._finishrebase()

            # and re-run as an on-disk merge.
            overrides = {('rebase', 'singletransaction'): True}
            with ui.configoverride(overrides, 'rebase'):
                return _dorebase(ui, repo, action, opts, inmemory=inmemory)
        except error.InMemoryMergeConflictsError:
            ui.warn(_('hit merge conflicts; re-running rebase without in-memory'
                      ' merge\n'))
            # TODO: Make in-memory merge not use the on-disk merge state, so
            # we don't have to clean it here
            mergemod.mergestate.clean(repo)
            clearstatus(repo)
            clearcollapsemsg(repo)
            return _dorebase(ui, repo, action, opts, inmemory=False)
    else:
        return _dorebase(ui, repo, action, opts)

def _dryrunrebase(ui, repo, action, opts):
    rbsrt = rebaseruntime(repo, ui, inmemory=True, opts=opts)
    confirm = opts.get('confirm')
    if confirm:
        ui.status(_('starting in-memory rebase\n'))
    else:
        ui.status(_('starting dry-run rebase; repository will not be '
                    'changed\n'))
    with repo.wlock(), repo.lock():
        needsabort = True
        try:
            overrides = {('rebase', 'singletransaction'): True}
            with ui.configoverride(overrides, 'rebase'):
                _origrebase(ui, repo, action, opts, rbsrt, inmemory=True,
                            leaveunfinished=True)
        except error.InMemoryMergeConflictsError:
            ui.status(_('hit a merge conflict\n'))
            return 1
        except error.Abort:
            needsabort = False
            raise
        else:
            if confirm:
                ui.status(_('rebase completed successfully\n'))
                if not ui.promptchoice(_(b'apply changes (yn)?'
                                         b'$$ &Yes $$ &No')):
                    # finish unfinished rebase
                    rbsrt._finishrebase()
                else:
                    rbsrt._prepareabortorcontinue(isabort=True, backup=False,
                                                  suppwarns=True)
                needsabort = False
            else:
                ui.status(_('dry-run rebase completed successfully; run without'
                            ' -n/--dry-run to perform this rebase\n'))
            return 0
        finally:
            if needsabort:
                # no need to store backup in case of dryrun
                rbsrt._prepareabortorcontinue(isabort=True, backup=False,
                                              suppwarns=True)

def _dorebase(ui, repo, action, opts, inmemory=False):
    rbsrt = rebaseruntime(repo, ui, inmemory, opts)
    return _origrebase(ui, repo, action, opts, rbsrt, inmemory=inmemory)

def _origrebase(ui, repo, action, opts, rbsrt, inmemory=False,
                leaveunfinished=False):
    assert action != 'stop'
    with repo.wlock(), repo.lock():
        # Validate input and define rebasing points
        destf = opts.get('dest', None)
        srcf = opts.get('source', None)

                if extensions.find('histedit'):
                    enablehistedit = ''
            except KeyError:
                enablehistedit = " --config extensions.histedit="
            help = "hg%s help -e histedit" % enablehistedit
            msg = _("interactive history editing is supported by the "
                    "'histedit' extension (see \"%s\")") % help
            raise error.Abort(msg)

        if rbsrt.collapsemsg and not rbsrt.collapsef:
            raise error.Abort(
                _('message can only be specified with collapse'))

        if action:
            if rbsrt.collapsef:
                raise error.Abort(
                    _('cannot use collapse with continue or abort'))
            if srcf or basef or destf:
                raise error.Abort(
                    _('abort and continue do not allow specifying revisions'))
            if action == 'abort' and opts.get('tool', False):
                ui.warn(_('tool option will be ignored\n'))
            if action == 'continue':
                ms = mergemod.mergestate.read(repo)
                mergeutil.checkunresolved(ms)

            retcode = rbsrt._prepareabortorcontinue(isabort=(action == 'abort'))
            if retcode is not None:
                return retcode
        else:
            destmap = _definedestmap(ui, repo, inmemory, destf, srcf, basef,
                                     revf, destspace=destspace)
            retcode = rbsrt._preparenewrebase(destmap)
            if retcode is not None:
                return retcode
            storecollapsemsg(repo, rbsrt.collapsemsg)

            with util.acceptintervention(dsguard):
                rbsrt._performrebase(tr)
                if not leaveunfinished:
                    rbsrt._finishrebase()

def _definedestmap(ui, repo, inmemory, destf=None, srcf=None, basef=None,
                   revf=None, destspace=None):
    """use revisions argument to define destmap {srcrev: destrev}"""
    if revf is None:
        revf = []

    # destspace is here to work around issues with `hg pull --rebase` see

    if not inmemory:
        cmdutil.checkunfinished(repo)
        cmdutil.bailifchanged(repo)

    if ui.configbool('commands', 'rebase.requiredest') and not destf:
        raise error.Abort(_('you must specify a destination'),
                          hint=_('use: hg rebase -d REV'))

    dest = None

    if revf:
        rebaseset = scmutil.revrange(repo, revf)

        rebaseset = repo.revs('(%ld)::', src)
        assert rebaseset
    else:
        base = scmutil.revrange(repo, [basef or '.'])
        if not base:
            ui.status(_('empty "base" revision set - '
                        "can't compute rebase set\n"))
            return None
        if destf:
            # --base does not support multiple destinations
            dest = scmutil.revsingle(repo, destf)
        else:
            dest = repo[_destrebase(repo, base, destspace=destspace)]
            destf = bytes(dest)

        roots = [] # selected children of branching points
        bpbase = {} # {branchingpoint: [origbase]}
        for b in base: # group bases by branching points
            bp = repo.revs('ancestor(%d, %d)', b, dest.rev()).first()
            bpbase[bp] = bpbase.get(bp, []) + [b]
        if None in bpbase:
            # emulate the old behavior, showing "nothing to rebase" (a better
            # behavior may be abort with "cannot find branching point" error)
            bpbase.clear()
        for bp, bs in bpbase.iteritems(): # calculate roots
            roots += list(repo.revs('children(%d) & ancestors(%ld)', bp, bs))

        rebaseset = repo.revs('%ld::', roots)

        if not rebaseset:
            # transform to list because smartsets are not comparable to
            # lists. This should be improved to honor laziness of
            # smartset.
            if list(base) == [dest.rev()]:
                if basef:
                    ui.status(_('nothing to rebase - %s is both "base"'
                                ' and destination\n') % dest)
                else:
                    ui.status(_('nothing to rebase - working directory '
                                'parent is also destination\n'))
            elif not repo.revs('%ld - ::%d', base, dest.rev()):
                if basef:
                    ui.status(_('nothing to rebase - "base" %s is '
                                'already an ancestor of destination '
                                '%s\n') %
                              ('+'.join(bytes(repo[r]) for r in base),
                               dest))
                else:
                    ui.status(_('nothing to rebase - working '
                                'directory parent is already an '
                                'ancestor of destination %s\n') % dest)
            else: # can it happen?
                ui.status(_('nothing to rebase from %s to %s\n') %
                          ('+'.join(bytes(repo[r]) for r in base), dest))
            return None

    rebasingwcp = repo['.'].rev() in rebaseset
    ui.log("rebase", "rebasing working copy parent: %r\n", rebasingwcp,
           rebase_rebasing_wcp=rebasingwcp)
    if inmemory and rebasingwcp:
        # Check these since we did not before.
        cmdutil.checkunfinished(repo)
        cmdutil.bailifchanged(repo)

                if size == 1:
                    destmap[r] = destset.first()
                elif size == 0:
                    ui.note(_('skipping %s - empty destination\n') % repo[r])
                else:
                    raise error.Abort(_('rebase destination for %s is not '
                                        'unique') % repo[r])

    if dest is not None:
        # single-dest case: assign dest to each rev in rebaseset
        destrev = dest.rev()
        destmap = {r: destrev for r in rebaseset} # {srcrev: destrev}

    if not destmap:
        ui.status(_('nothing to rebase - empty destination\n'))
        return None

    return destmap

def externalparent(repo, state, destancestors):
    """Return the revision that should be used as the second parent
    when the revisions in state is collapsed on top of destancestors.
    Abort if there is more than one parent.

    source = min(state)
    for rev in state:
        if rev == source:
            continue
        for p in repo[rev].parents():
            if (p.rev() not in state
                        and p.rev() not in destancestors):
                parents.add(p.rev())
    if not parents:
        return nullrev
    if len(parents) == 1:
        return parents.pop()
    raise error.Abort(_('unable to collapse on top of %d, there is more '
                       'than one external parent: %s') %
                     (max(destancestors),
                      ', '.join("%d" % p for p in sorted(parents))))

def commitmemorynode(repo, p1, p2, wctx, editor, extra, user, date, commitmsg):
    '''Commit the memory changes with parents p1 and p2.
    Return node of committed revision.'''
    # Replicates the empty check in ``repo.commit``.

    # ``branch`` (used when passing ``--keepbranches``).
    branch = repo[p1].branch()
    if 'branch' in extra:
        branch = extra['branch']

    memctx = wctx.tomemctx(commitmsg, parents=(p1, p2), date=date,
        extra=extra, user=user, branch=branch, editor=editor)
    commitres = repo.commitctx(memctx)
    wctx.clean() # Might be reused
    return commitres

def commitnode(repo, p1, p2, editor, extra, user, date, commitmsg):
    '''Commit the wd changes with parents p1 and p2.
    Return node of committed revision.'''
    dsguard = util.nullcontextmanager()

        dsguard = dirstateguard.dirstateguard(repo, 'rebase')
    with dsguard:
        repo.setparents(repo[p1].node(), repo[p2].node())

        # Commit might fail if unresolved files exist
        newnode = repo.commit(text=commitmsg, user=user, date=date,
                              extra=extra, editor=editor)

        repo.dirstate.setbranch(repo[newnode].branch())
        return newnode

def rebasenode(repo, rev, p1, base, collapse, dest, wctx):
    'Rebase a single revision rev on top of p1 using base as merge ancestor'
    # Merge phase
    # Update to destination and merge it with local

    repo.ui.debug(" merge against %d:%s\n" % (rev, repo[rev]))
    if base is not None:
        repo.ui.debug("   detach base %d:%s\n" % (base, repo[base]))
    # When collapsing in-place, the parent is the common ancestor, we
    # have to allow merging with it.
    stats = mergemod.update(repo, rev, branchmerge=True, force=True,
                            ancestor=base, mergeancestor=collapse,
                            labels=['dest', 'source'], wc=wctx)
    if collapse:
        copies.duplicatecopies(repo, wctx, rev, dest)
    else:
        # If we're not using --collapse, we need to
        # duplicate copies between the revision we're

        # duplicate any copies that have already been
        # performed in the destination.
        p1rev = repo[rev].p1().rev()
        copies.duplicatecopies(repo, wctx, rev, p1rev, skiprev=dest)
    return stats

def adjustdest(repo, rev, destmap, state, skipped):
    r"""adjust rebase destination given the current rebase state

    rev is what is being rebased. Return a list of two revs, which are the

       \ /
        A
    """
    # pick already rebased revs with same dest from state as interesting source
    dest = destmap[rev]
    source = [s for s, d in state.items()
              if d > 0 and destmap[s] == dest and s not in skipped]

    result = []
    for prev in repo.changelog.parentrevs(rev):
        adjusted = dest
        if prev != nullrev:

        if adjusted == dest and dest in state:
            adjusted = state[dest]
            if adjusted == revtodo:
                # sortsource should produce an order that makes this impossible
                raise error.ProgrammingError(
                    'rev %d should be rebased already at this time' % dest)
        result.append(adjusted)
    return result

def _checkobsrebase(repo, ui, rebaseobsrevs, rebaseobsskipped):
    """
    Abort if rebase will create divergence or rebase is noop because of markers

    `rebaseobsrevs`: set of obsolete revision in source
    `rebaseobsskipped`: set of revisions from source skipped because they have
    successors in destination or no non-obsolete successor.
    """
    # Obsolete node with successors not in dest leads to divergence
    divergenceok = ui.configbool('experimental',
                                 'evolution.allowdivergence')
    divergencebasecandidates = rebaseobsrevs - rebaseobsskipped

    if divergencebasecandidates and not divergenceok:
        divhashes = (bytes(repo[r])
                     for r in divergencebasecandidates)
        msg = _("this rebase will cause "
                "divergences from: %s")
        h = _("to force the rebase please set "
              "experimental.evolution.allowdivergence=True")
        raise error.Abort(msg % (",".join(divhashes),), hint=h)

def successorrevs(unfi, rev):
    """yield revision numbers for successors of rev"""
    assert unfi.filtername is None
    nodemap = unfi.changelog.nodemap
    for s in obsutil.allsuccessors(unfi.obsstore, [unfi[rev].node()]):
        if s in nodemap:
            yield nodemap[s]

def defineparents(repo, rev, destmap, state, skipped, obsskipped):
    """Return new parents and optionally a merge base for rev being rebased

    The destination specified by "dest" cannot always be used directly because
    previously rebase result could affect destination. For example,

    assert repo.filtername is None
    cl = repo.changelog
    isancestor = cl.isancestorrev

    dest = destmap[rev]
    oldps = repo.changelog.parentrevs(rev) # old parents
    newps = [nullrev, nullrev] # new parents
    dests = adjustdest(repo, rev, destmap, state, skipped)
    bases = list(oldps) # merge base candidates, initially just old parents

    if all(r == nullrev for r in oldps[1:]):
        # For non-merge changeset, just move p to adjusted dest as requested.
        newps[0] = dests[0]
    else:

        #   A B D  # B (using rule "2."), since B will be rebased.
        #
        # The loop tries to be not rely on the fact that a Mercurial node has
        # at most 2 parents.
        for i, p in enumerate(oldps):
            np = p # new parent
            if any(isancestor(x, dests[i]) for x in successorrevs(repo, p)):
                np = dests[i]
            elif p in state and state[p] > 0:
                np = state[p]

            # If one parent becomes an ancestor of the other, drop the ancestor
            for j, x in enumerate(newps[:i]):
                if x == nullrev:
                    continue
                if isancestor(np, x): # CASE-1
                    np = nullrev
                elif isancestor(x, np): # CASE-2
                    newps[j] = np
                    np = nullrev
                    # New parents forming an ancestor relationship does not
                    # mean the old parents have a similar relationship. Do not
                    # set bases[x] to nullrev.

        #
        #     C    # rebase -r C -d D
        #    /|    # None of A and B will be changed to D and rebase fails.
        #   A B D
        if set(newps) == set(oldps) and dest not in newps:
            raise error.Abort(_('cannot rebase %d:%s without '
                                'moving at least one of its parents')
                              % (rev, repo[rev]))

    # Source should not be ancestor of dest. The check here guarantees it's
    # impossible. With multi-dest, the initial check does not cover complex
    # cases since we don't have abstractions to dry-run rebase cheaply.
    if any(p != nullrev and isancestor(rev, p) for p in newps):

    #
    # But our merge base candidates (D and E in above case) could still be
    # better than the default (ancestor(F, Z) == null). Therefore still
    # pick one (so choose p1 above).
    if sum(1 for b in bases if b != nullrev) > 1:
        unwanted = [None, None] # unwanted[i]: unwanted revs if choose bases[i]
        for i, base in enumerate(bases):
            if base == nullrev:
                continue
            # Revisions in the side (not chosen as merge base) branch that
            # might contain "surprising" contents
            siderevs = list(repo.revs('((%ld-%d) %% (%d+%d))',
                                      bases, base, base, dest))

            # If those revisions are covered by rebaseset, the result is good.
            # A merge in rebaseset would be considered to cover its ancestors.
            if siderevs:
                rebaseset = [r for r, d in state.items()
                             if d > 0 and r not in obsskipped]
                merges = [r for r in rebaseset
                          if cl.parentrevs(r)[1] != nullrev]
                unwanted[i] = list(repo.revs('%ld - (::%ld) - %ld',
                                             siderevs, merges, rebaseset))

        # Choose a merge base that has a minimal number of unwanted revs.
        l, i = min((len(revs), i)
                   for i, revs in enumerate(unwanted) if revs is not None)
        base = bases[i]

        # newps[0] should match merge base if possible. Currently, if newps[i]
        # is nullrev, the only case is newps[i] and newps[j] (j < i), one is
        # the other's ancestor. In that case, it's fine to not swap newps here.

        # The merge will include unwanted revisions. Abort now. Revisit this if
        # we have a more advanced merge algorithm that handles multiple bases.
        if l > 0:
            unwanteddesc = _(' or ').join(
                (', '.join('%d:%s' % (r, repo[r]) for r in revs)
                 for revs in unwanted if revs is not None))
            raise error.Abort(
                _('rebasing %d:%s will include unwanted changes from %s')
                % (rev, repo[rev], unwanteddesc))

    repo.ui.debug(" future parents are %d and %d\n" % tuple(newps))

    return newps[0], newps[1], base

def isagitpatch(repo, patchname):
    'Return true if the given patch is in git format'
    mqpatch = os.path.join(repo.mq.path, patchname)
    for line in patch.linereader(open(mqpatch, 'rb')):
        if line.startswith('diff --git'):
            return True
    return False

def updatemq(repo, state, skipped, **opts):
    'Update rebased mq patches - finalize and then import them'
    mqrebase = {}
    mq = repo.mq
    original_series = mq.fullseries[:]
    skippedpatches = set()

    for p in mq.applied:
        rev = repo[p.node].rev()
        if rev in state:
            repo.ui.debug('revision %d is an mq patch (%s), finalize it.\n' %
                                        (rev, p.name))
            mqrebase[rev] = (p.name, isagitpatch(repo, p.name))
        else:
            # Applied but not rebased, not sure this should happen
            skippedpatches.add(p.name)

        # We must start import from the newest revision
        for rev in sorted(mqrebase, reverse=True):
            if rev not in skipped:
                name, isgit = mqrebase[rev]
                repo.ui.note(_('updating mq patch %s to %d:%s\n') %
                             (name, state[rev], repo[state[rev]]))
                mq.qimport(repo, (), patchname=name, git=isgit,
                                rev=["%d" % state[rev]])
            else:
                # Rebased and skipped
                skippedpatches.add(mqrebase[rev][0])

        # Patches were either applied and rebased and imported in
        # order, applied and removed or unapplied. Discard the removed
        # ones while preserving the original series order and guards.
        newseries = [s for s in original_series
                     if mq.guard_re.split(s, 1)[0] not in skippedpatches]
        mq.fullseries[:] = newseries
        mq.seriesdirty = True
        mq.savedirty()

def storecollapsemsg(repo, collapsemsg):
    'Store the collapse message to allow recovery'
    collapsemsg = collapsemsg or ''
    f = repo.vfs("last-message.txt", "w")
    f.write("%s\n" % collapsemsg)
    f.close()

def clearcollapsemsg(repo):
    'Remove collapse message file'
    repo.vfs.unlinkpath("last-message.txt", ignoremissing=True)

def restorecollapsemsg(repo, isabort):
    'Restore previously stored collapse message'
    try:
        f = repo.vfs("last-message.txt")

            collapsemsg = ''
        else:
            raise error.Abort(_('missing .hg/last-message.txt for rebase'))
    return collapsemsg

def clearstatus(repo):
    'Remove the status files'
    # Make sure the active transaction won't write the state file
    tr = repo.currenttransaction()
    if tr:
        tr.removefilegenerator('rebasestate')
    repo.vfs.unlinkpath("rebasestate", ignoremissing=True)

def needupdate(repo, state):
    '''check whether we should `update --clean` away from a merge, or if
    somehow the working dir got forcibly updated, e.g. by older hg'''
    parents = [p.rev() for p in repo[None].parents()]

    # Are we in a merge state at all?
    if len(parents) < 2:
        return False

    # We should be standing on the first as-of-yet unrebased commit.
    firstunrebased = min([old for old, new in state.iteritems()
                          if new == nullrev])
    if firstunrebased in parents:
        return True

    return False

def sortsource(destmap):
    """yield source revisions in an order that we only rebase things once

    If source and destination overlaps, we should filter out revisions

        if not result:
            raise error.Abort(_('source and destination form a cycle'))
        srcset -= set(result)
        yield result

def buildstate(repo, destmap, collapse):
    '''Define which revisions are going to be rebased and where

    repo: repo
    destmap: {srcrev: destrev}

        mqapplied = set(repo[s.node].rev() for s in repo.mq.applied)
        if set(destmap.values()) & mqapplied:
            raise error.Abort(_('cannot rebase onto an applied mq patch'))

    # Get "cycle" error early by exhausting the generator.
    sortedsrc = list(sortsource(destmap)) # a list of sorted revs
    if not sortedsrc:
        raise error.Abort(_('no matching revisions'))

    # Only check the first batch of revisions to rebase not depending on other
    # rebaseset. This means "source is ancestor of destination" for the second
    # (and following) batches of revisions are not checked here. We rely on
    # "defineparents" to do that check.
    roots = list(repo.set('roots(%ld)', sortedsrc[0]))
    if not roots:
        raise error.Abort(_('no matching revisions'))
    def revof(r):
        return r.rev()
    roots = sorted(roots, key=revof)
    state = dict.fromkeys(rebaseset, revtodo)
    emptyrebase = (len(sortedsrc) == 1)
    for root in roots:
        dest = repo[destmap[root.rev()]]
        commonbase = root.ancestor(dest)
        if commonbase == root:
            raise error.Abort(_('source is ancestor of destination'))

        # if all parents of this revision are done, then so is this revision
        if parents and all((state.get(p) == p for p in parents)):
            state[rev] = rev
    return originalwd, destmap, state

def clearrebased(ui, repo, destmap, state, skipped, collapsedas=None,
                 keepf=False, fm=None, backup=True):
    """dispose of rebased revision at the end of the rebase

    If `collapsedas` is not None, the rebase was a collapse whose result if the
    `collapsedas` node.

        fm.data(nodechanges=nodechanges)
    if keepf:
        replacements = {}
    scmutil.cleanupnodes(repo, replacements, 'rebase', moves, backup=backup)

def pullrebase(orig, ui, repo, *args, **opts):
    'Call rebase after pull if the latter has been invoked with --rebase'
    if opts.get(r'rebase'):
        if ui.configbool('commands', 'rebase.requiredest'):
            msg = _('rebase destination required by configuration')

            raise error.Abort(msg, hint=hint)

        with repo.wlock(), repo.lock():
            if opts.get(r'update'):
                del opts[r'update']
                ui.debug('--update and --rebase are not compatible, ignoring '
                         'the update flag\n')

            cmdutil.checkunfinished(repo, skipmerge=True)
            cmdutil.bailifchanged(repo, hint=_('cannot pull with rebase: '
                'please commit or shelve your changes first'))

            revsprepull = len(repo)
            origpostincoming = commands.postincoming
            def _dummy(*args, **kwargs):
                pass
            commands.postincoming = _dummy
            try:
                ret = orig(ui, repo, *args, **opts)
            finally:
                commands.postincoming = origpostincoming

            raise error.Abort(_('--tool can only be used with --rebase'))
        ret = orig(ui, repo, *args, **opts)

    return ret

def _filterobsoleterevs(repo, revs):
    """returns a set of the obsolete revisions in revs"""
    return set(r for r in revs if repo[r].obsolete())

def _computeobsoletenotrebased(repo, rebaseobsrevs, destmap):
    """Return (obsoletenotrebased, obsoletewithoutsuccessorindestination).

    `obsoletenotrebased` is a mapping mapping obsolete => successor for all

        obsoletenotrebased,
        obsoletewithoutsuccessorindestination,
        obsoleteextinctsuccessors,
    )

def abortrebase(ui, repo):
    with repo.wlock(), repo.lock():
        rbsrt = rebaseruntime(repo, ui)
        rbsrt._prepareabortorcontinue(isabort=True)

def continuerebase(ui, repo):
    with repo.wlock(), repo.lock():
        rbsrt = rebaseruntime(repo, ui)
        ms = mergemod.mergestate.read(repo)

        retcode = rbsrt._prepareabortorcontinue(isabort=False)
        if retcode is not None:
            return retcode
        rbsrt._performrebase(None)
        rbsrt._finishrebase()

def summaryhook(ui, repo):
    if not repo.vfs.exists('rebasestate'):
        return
    try:

        msg = _('rebase: (use "hg rebase --abort" to clear broken state)\n')
        ui.write(msg)
        return
    numrebased = len([i for i in state.itervalues() if i >= 0])
    # i18n: column positioning for "hg summary"
    ui.write(_('rebase: %s, %s (rebase --continue)\n') %
             (ui.label(_('%d rebased'), 'rebase.rebased') % numrebased,
              ui.label(_('%d remaining'), 'rebase.remaining') %
              (len(state) - numrebased)))

def uisetup(ui):
    #Replace pull with a decorator to provide --rebase option
    entry = extensions.wrapcommand(commands.table, 'pull', pullrebase)
    entry[1].append(('', 'rebase', None,
                     _("rebase working directory to branch head")))
    entry[1].append(('t', 'tool', '',
                     _("specify merge tool for rebase")))
    cmdutil.summaryhooks.add('rebase', summaryhook)
    statemod.addunfinished('rebase', fname='rebasestate', stopflag=True,
                            continueflag=True, abortfunc=abortrebase,
                            continuefunc=continuerebase)

43076:2372284d9457

# 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'


def _nothingtorebase():
    return 1


def _savegraft(ctx, extra):
    s = ctx.extra().get('source', None)
    if s is not None:
        extra['source'] = s
    s = ctx.extra().get('intermediate-source', None)
    if s is not None:
        extra['intermediate-source'] = s


def _savebranch(ctx, extra):
    extra['branch'] = ctx.branch()


def _destrebase(repo, sourceset, destspace=None):
    """small wrapper around destmerge to pass the right extra args

    Please wrap destutil.destmerge instead."""
    return destutil.destmerge(
        repo,
        action='rebase',
        sourceset=sourceset,
        onheadcheck=False,
        destspace=destspace,
    )


revsetpredicate = registrar.revsetpredicate()


@revsetpredicate('_destrebase')
def _revsetdestrebase(repo, subset, x):
    # ``_rebasedefaultdest()``

    sourceset = None
    if x is not None:
        sourceset = revset.getset(repo, smartset.fullreposet(repo), x)
    return subset & smartset.baseset([_destrebase(repo, sourceset)])


@revsetpredicate('_destautoorphanrebase')
def _revsetdestautoorphanrebase(repo, subset, x):
    # ``_destautoorphanrebase()``

    # automatic rebase destination for a single orphan revision.

    if not src or src in obsoleted:
        return smartset.baseset()
    dests = destutil.orphanpossibledestination(repo, src)
    if len(dests) > 1:
        raise error.Abort(
            _("ambiguous automatic rebase: %r could end up on any of %r")
            % (src, dests)
        )
    # We have zero or one destination, so we can just return here.
    return smartset.baseset(dests)


def _ctxdesc(ctx):
    """short description for a context"""
    desc = '%d:%s "%s"' % (ctx.rev(), ctx, ctx.description().split('\n', 1)[0])
    repo = ctx.repo()
    names = []
    for nsname, ns in repo.names.iteritems():
        if nsname == 'branches':
            continue
        names.extend(ns.names(repo, ctx.node()))
    if names:
        desc += ' (%s)' % ' '.join(names)
    return desc


class rebaseruntime(object):
    """This class is a container for rebase runtime state"""

    def __init__(self, repo, ui, inmemory=False, opts=None):
        if opts is None:
            opts = {}

        # prepared: whether we have rebasestate prepared or not. Currently it

        self.collapsef = opts.get('collapse', False)
        self.collapsemsg = cmdutil.logmessage(ui, opts)
        self.date = opts.get('date', None)

        e = opts.get('extrafn')  # internal, used by e.g. hgsubversion
        self.extrafns = [_savegraft]
        if e:
            self.extrafns = [e]

        self.backupf = ui.configbool('rewrite', 'backup-bundle')

            return self._repo

    def storestatus(self, tr=None):
        """Store the current status to allow recovery"""
        if tr:
            tr.addfilegenerator(
                'rebasestate',
                ('rebasestate',),
                self._writestatus,
                location='plain',
            )
        else:
            with self.repo.vfs("rebasestate", "w") as f:
                self._writestatus(f)

    def _writestatus(self, f):

    def _read(self):
        self.prepared = True
        repo = self.repo
        assert repo.filtername is None
        data = {
            'keepbranches': None,
            'collapse': None,
            'activebookmark': None,
            'external': nullrev,
            'keep': None,
            'originalwd': None,
        }
        legacydest = None
        state = {}
        destmap = {}

        if True:

            for old, new in sorted(state.items()):
                if new != revtodo and new in seen:
                    skipped.add(old)
                seen.add(new)
        data['skipped'] = skipped
        repo.ui.debug(
            'computed skipped revs: %s\n'
            % (' '.join('%d' % r for r in sorted(skipped)) or '')
        )

        return data

    def _handleskippingobsolete(self, obsoleterevs, destmap):
        """Compute structures necessary for skipping obsolete revisions

        """
        self.obsoletenotrebased = {}
        if not self.ui.configbool('experimental', 'rebaseskipobsolete'):
            return
        obsoleteset = set(obsoleterevs)
        (
            self.obsoletenotrebased,
            self.obsoletewithoutsuccessorindestination,
            obsoleteextinctsuccessors,
        ) = _computeobsoletenotrebased(self.repo, obsoleteset, destmap)
        skippedset = set(self.obsoletenotrebased)
        skippedset.update(self.obsoletewithoutsuccessorindestination)
        skippedset.update(obsoleteextinctsuccessors)
        _checkobsrebase(self.repo, self.ui, obsoleteset, skippedset)

            self.collapsemsg = restorecollapsemsg(self.repo, isabort)
        except error.RepoLookupError:
            if isabort:
                clearstatus(self.repo)
                clearcollapsemsg(self.repo)
                self.repo.ui.warn(
                    _(
                        'rebase aborted (no revision is removed,'
                        ' only broken state is cleared)\n'
                    )
                )
                return 0
            else:
                msg = _('cannot continue inconsistent rebase')
                hint = _('use "hg rebase --abort" to clear broken state')
                raise error.Abort(msg, hint=hint)

        if not destmap:
            return _nothingtorebase()

        rebaseset = destmap.keys()
        allowunstable = obsolete.isenabled(self.repo, obsolete.allowunstableopt)
        if not (self.keepf or allowunstable) and self.repo.revs(
            'first(children(%ld) - %ld)', rebaseset, rebaseset
        ):
            raise error.Abort(
                _(
                    "can't remove original changesets with"
                    " unrebased descendants"
                ),
                hint=_('use --keep to keep original changesets'),
            )

        result = buildstate(self.repo, destmap, self.collapsef)

        if not result:
            # Empty state built, nothing to rebase
            self.ui.status(_('nothing to rebase\n'))
            return _nothingtorebase()

        for root in self.repo.set('roots(%ld)', rebaseset):
            if not self.keepf and not root.mutable():
                raise error.Abort(
                    _("can't rebase public changeset %s") % root,
                    hint=_("see 'hg help phases' for details"),
                )

        (self.originalwd, self.destmap, self.state) = result
        if self.collapsef:
            dests = set(self.destmap.values())
            if len(dests) != 1:
                raise error.Abort(
                    _('--collapse does not work with multiple destinations')
                )
            destrev = next(iter(dests))
            destancestors = self.repo.changelog.ancestors(
                [destrev], inclusive=True
            )
            self.external = externalparent(self.repo, self.state, destancestors)

        for destrev in sorted(set(destmap.values())):
            dest = self.repo[destrev]
            if dest.closesbranch() and not self.keepbranchesf:

        self.prepared = True

    def _assignworkingcopy(self):
        if self.inmemory:
            from mercurial.context import overlayworkingctx

            self.wctx = overlayworkingctx(self.repo)
            self.repo.ui.debug("rebasing in-memory\n")
        else:
            self.wctx = self.repo[None]
            self.repo.ui.debug("rebasing on disk\n")
        self.repo.ui.log(
            "rebase",
            "using in-memory rebase: %r\n",
            self.inmemory,
            rebase_imm_used=self.inmemory,
        )

    def _performrebase(self, tr):
        self._assignworkingcopy()
        repo, ui = self.repo, self.ui
        if self.keepbranchesf:

            if self.collapsef:
                branches = set()
                for rev in self.state:
                    branches.add(repo[rev].branch())
                    if len(branches) > 1:
                        raise error.Abort(
                            _('cannot collapse multiple named ' 'branches')
                        )

        # Calculate self.obsoletenotrebased
        obsrevs = _filterobsoleterevs(self.repo, self.state)
        self._handleskippingobsolete(obsrevs, self.destmap)

            # When using single transaction, store state when transaction
            # commits.
            self.storestatus(tr)

        cands = [k for k, v in self.state.iteritems() if v == revtodo]
        p = repo.ui.makeprogress(
            _("rebasing"), unit=_('changesets'), total=len(cands)
        )

        def progress(ctx):
            p.increment(item=("%d:%s" % (ctx.rev(), ctx)))

        allowdivergence = self.ui.configbool(
            'experimental', 'evolution.allowdivergence'
        )
        for subset in sortsource(self.destmap):
            sortedrevs = self.repo.revs('sort(%ld, -topo)', subset)
            if not allowdivergence:
                sortedrevs -= self.repo.revs(
                    'descendants(%ld) and not %ld',

        overrides = {('phases', 'new-commit'): destphase}
        if keepbranch:
            overrides[('ui', 'allowemptycommit')] = True
        with repo.ui.configoverride(overrides, 'rebase'):
            if self.inmemory:
                newnode = commitmemorynode(
                    repo,
                    p1,
                    p2,
                    wctx=self.wctx,
                    extra=extra,
                    commitmsg=commitmsg,
                    editor=editor,
                    user=ctx.user(),
                    date=date,
                )
                mergemod.mergestate.clean(repo)
            else:
                newnode = commitnode(
                    repo,
                    p1,
                    p2,
                    extra=extra,
                    commitmsg=commitmsg,
                    editor=editor,
                    user=ctx.user(),
                    date=date,
                )

            if newnode is None:
                # If it ended up being a no-op commit, then the normal
                # merge state clean-up path doesn't happen, so do it
                # here. Fix issue5494

        dest = self.destmap[rev]
        ctx = repo[rev]
        desc = _ctxdesc(ctx)
        if self.state[rev] == rev:
            ui.status(_('already rebased %s\n') % desc)
        elif (
            not allowdivergence
            and rev in self.obsoletewithoutsuccessorindestination
        ):
            msg = (
                _(
                    'note: not rebasing %s and its descendants as '
                    'this would cause divergence\n'
                )
                % desc
            )
            repo.ui.status(msg)
            self.skipped.add(rev)
        elif rev in self.obsoletenotrebased:
            succ = self.obsoletenotrebased[rev]
            if succ is None:
                msg = (
                    _('note: not rebasing %s, it has no ' 'successor\n') % desc
                )
            else:
                succdesc = _ctxdesc(repo[succ])
                msg = _(
                    'note: not rebasing %s, already in ' 'destination as %s\n'
                ) % (desc, succdesc)
            repo.ui.status(msg)
            # Make clearrebased aware state[rev] is not a true successor
            self.skipped.add(rev)
            # Record rev as moved to its desired destination in self.state.
            # This helps bookmark and working parent movement.
            dest = max(
                adjustdest(repo, rev, self.destmap, self.state, self.skipped)
            )
            self.state[rev] = dest
        elif self.state[rev] == revtodo:
            ui.status(_('rebasing %s\n') % desc)
            progressfn(ctx)
            p1, p2, base = defineparents(
                repo,
                rev,
                self.destmap,
                self.state,
                self.skipped,
                self.obsoletenotrebased,
            )
            if not self.inmemory and len(repo[None].parents()) == 2:
                repo.ui.debug('resuming interrupted rebase\n')
            else:
                overrides = {('ui', 'forcemerge'): opts.get('tool', '')}
                with ui.configoverride(overrides, 'rebase'):
                    stats = rebasenode(
                        repo,
                        rev,
                        p1,
                        base,
                        self.collapsef,
                        dest,
                        wctx=self.wctx,
                    )
                    if stats.unresolvedcount > 0:
                        if self.inmemory:
                            raise error.InMemoryMergeConflictsError()
                        else:
                            raise error.InterventionRequired(
                                _(
                                    'unresolved conflicts (see hg '
                                    'resolve, then hg rebase --continue)'
                                )
                            )
            if not self.collapsef:
                merging = p2 != nullrev
                editform = cmdutil.mergeeditform(merging, 'rebase')
                editor = cmdutil.getcommiteditor(
                    editform=editform, **pycompat.strkwargs(opts)
                )
                newnode = self._concludenode(rev, p1, p2, editor)
            else:
                # Skip commit if we are collapsing
                if self.inmemory:
                    self.wctx.setbase(repo[p1])

            if newnode is not None:
                self.state[rev] = repo[newnode].rev()
                ui.debug('rebased as %s\n' % short(newnode))
            else:
                if not self.collapsef:
                    ui.warn(
                        _(
                            'note: not rebasing %s, its destination already '
                            'has all its changes\n'
                        )
                        % desc
                    )
                    self.skipped.add(rev)
                self.state[rev] = p1
                ui.debug('next revision set to %d\n' % p1)
        else:
            ui.status(
                _('already rebased %s as %s\n') % (desc, repo[self.state[rev]])
            )
        if not tr:
            # When not using single transaction, store state after each
            # commit is completely done. On InterventionRequired, we thus
            # won't store the status. Instead, we'll hit the "len(parents) == 2"
            # case and realize that the commit was in progress.

    def _finishrebase(self):
        repo, ui, opts = self.repo, self.ui, self.opts
        fm = ui.formatter('rebase', opts)
        fm.startitem()
        if self.collapsef:
            p1, p2, _base = defineparents(
                repo,
                min(self.state),
                self.destmap,
                self.state,
                self.skipped,
                self.obsoletenotrebased,
            )
            editopt = opts.get('edit')
            editform = 'rebase.collapse'
            if self.collapsemsg:
                commitmsg = self.collapsemsg
            else:

                        commitmsg += '\n* %s' % repo[rebased].description()
                editopt = True
            editor = cmdutil.getcommiteditor(edit=editopt, editform=editform)
            revtoreuse = max(self.state)

            newnode = self._concludenode(
                revtoreuse, p1, self.external, editor, commitmsg=commitmsg
            )

            if newnode is not None:
                newrev = repo[newnode].rev()
                for oldrev in self.state:
                    self.state[oldrev] = newrev

        if 'qtip' in repo.tags():
            updatemq(repo, self.state, self.skipped, **pycompat.strkwargs(opts))

        # restore original working directory
        # (we do this before stripping)
        newwd = self.state.get(self.originalwd, self.originalwd)
        if newwd < 0:

            hg.updaterepo(repo, newwd, overwrite=False)

        collapsedas = None
        if self.collapsef and not self.keepf:
            collapsedas = newnode
        clearrebased(
            ui,
            repo,
            self.destmap,
            self.state,
            self.skipped,
            collapsedas,
            self.keepf,
            fm=fm,
            backup=self.backupf,
        )

        clearstatus(repo)
        clearcollapsemsg(repo)

        ui.note(_("rebase completed\n"))

        if self.skipped:
            skippedlen = len(self.skipped)
            ui.note(_("%d revisions have been skipped\n") % skippedlen)
        fm.end()

        if (
            self.activebookmark
            and self.activebookmark in repo._bookmarks
            and repo['.'].node() == repo._bookmarks[self.activebookmark]
        ):
            bookmarks.activate(repo, self.activebookmark)

    def _abort(self, backup=True, suppwarns=False):
        '''Restore the repository to its original state.'''

        repo = self.repo
        try:
            # If the first commits in the rebased set get skipped during the
            # rebase, their values within the state mapping will be the dest
            # rev id. The rebased list must must not contain the dest rev
            # (issue4896)
            rebased = [
                s
                for r, s in self.state.items()
                if s >= 0 and s != r and s != self.destmap[r]
            ]
            immutable = [d for d in rebased if not repo[d].mutable()]
            cleanup = True
            if immutable:
                repo.ui.warn(
                    _("warning: can't clean up public changesets %s\n")
                    % ', '.join(bytes(repo[r]) for r in immutable),
                    hint=_("see 'hg help phases' for details"),
                )
                cleanup = False

            descendants = set()
            if rebased:
                descendants = set(repo.changelog.descendants(rebased))
            if descendants - set(rebased):
                repo.ui.warn(
                    _(
                        "warning: new changesets detected on "
                        "destination branch, can't strip\n"
                    )
                )
                cleanup = False

            if cleanup:
                shouldupdate = False
                if rebased:
                    strippoints = [
                        c.node() for c in repo.set('roots(%ld)', rebased)
                    ]

                updateifonnodes = set(rebased)
                updateifonnodes.update(self.destmap.values())
                updateifonnodes.add(self.originalwd)
                shouldupdate = repo['.'].rev() in updateifonnodes

                # Update away from the rebase if necessary
                if shouldupdate or needupdate(repo, self.state):
                    mergemod.update(
                        repo, self.originalwd, branchmerge=False, force=True
                    )

                # Strip from the first rebased revision
                if rebased:
                    repair.strip(repo.ui, repo, strippoints, backup=backup)

            clearcollapsemsg(repo)
            if not suppwarns:
                repo.ui.warn(_('rebase aborted\n'))
        return 0


@command(
    'rebase',
    [
        (
            's',
            'source',
            '',
            _('rebase the specified changeset and descendants'),
            _('REV'),
        ),
        (
            'b',
            'base',
            '',
            _('rebase everything from branching point of specified changeset'),
            _('REV'),
        ),
        ('r', 'rev', [], _('rebase these revisions'), _('REV')),
        ('d', 'dest', '', _('rebase onto the specified changeset'), _('REV')),
        ('', 'collapse', False, _('collapse the rebased changesets')),
        (
            'm',
            'message',
            '',
            _('use text as collapse commit message'),
            _('TEXT'),
        ),
        ('e', 'edit', False, _('invoke editor on commit messages')),
        (
            'l',
            'logfile',
            '',
            _('read collapse commit message from file'),
            _('FILE'),
        ),
        ('k', 'keep', False, _('keep original changesets')),
        ('', 'keepbranches', False, _('keep original branch names')),
        ('D', 'detach', False, _('(DEPRECATED)')),
        ('i', 'interactive', False, _('(DEPRECATED)')),
        ('t', 'tool', '', _('specify merge tool')),
        ('', 'stop', False, _('stop interrupted rebase')),
        ('c', 'continue', False, _('continue an interrupted rebase')),
        ('a', 'abort', False, _('abort an interrupted rebase')),
        (
            '',
            'auto-orphans',
            '',
            _(
                'automatically rebase orphan revisions '
                'in the specified revset (EXPERIMENTAL)'
            ),
        ),
    ]
    + cmdutil.dryrunopts
    + cmdutil.formatteropts
    + cmdutil.confirmopts,
    _('[-s REV | -b REV] [-d REV] [OPTION]'),
    helpcategory=command.CATEGORY_CHANGE_MANAGEMENT,
)
def rebase(ui, repo, **opts):
    """move changeset (and descendants) to a different branch

    Rebase uses repeated merging to graft changesets from one part of
    history (the source) onto another (the destination). This can be

    inmemory = ui.configbool('rebase', 'experimental.inmemory')
    dryrun = opts.get('dry_run')
    confirm = opts.get('confirm')
    selactions = [k for k in ['abort', 'stop', 'continue'] if opts.get(k)]
    if len(selactions) > 1:
        raise error.Abort(
            _('cannot use --%s with --%s') % tuple(selactions[:2])
        )
    action = selactions[0] if selactions else None
    if dryrun and action:
        raise error.Abort(_('cannot specify both --dry-run and --%s') % action)
    if confirm and action:
        raise error.Abort(_('cannot specify both --confirm and --%s') % action)

        inmemory = False

    if opts.get('auto_orphans'):
        for key in opts:
            if key != 'auto_orphans' and opts.get(key):
                raise error.Abort(
                    _('--auto-orphans is incompatible with %s') % ('--' + key)
                )
        userrevs = list(repo.revs(opts.get('auto_orphans')))
        opts['rev'] = [revsetlang.formatspec('%ld and orphan()', userrevs)]
        opts['dest'] = '_destautoorphanrebase(SRC)'

    if dryrun or confirm:

            rbsrt.restorestatus()
            if rbsrt.collapsef:
                raise error.Abort(_("cannot stop in --collapse session"))
            allowunstable = obsolete.isenabled(repo, obsolete.allowunstableopt)
            if not (rbsrt.keepf or allowunstable):
                raise error.Abort(
                    _(
                        "cannot remove original changesets with"
                        " unrebased descendants"
                    ),
                    hint=_(
                        'either enable obsmarkers to allow unstable '
                        'revisions or use --keep to keep original '
                        'changesets'
                    ),
                )
            if needupdate(repo, rbsrt.state):
                # update to the current working revision
                # to clear interrupted merge
                hg.updaterepo(repo, rbsrt.originalwd, overwrite=True)
            rbsrt._finishrebase()

            # and re-run as an on-disk merge.
            overrides = {('rebase', 'singletransaction'): True}
            with ui.configoverride(overrides, 'rebase'):
                return _dorebase(ui, repo, action, opts, inmemory=inmemory)
        except error.InMemoryMergeConflictsError:
            ui.warn(
                _(
                    'hit merge conflicts; re-running rebase without in-memory'
                    ' merge\n'
                )
            )
            # TODO: Make in-memory merge not use the on-disk merge state, so
            # we don't have to clean it here
            mergemod.mergestate.clean(repo)
            clearstatus(repo)
            clearcollapsemsg(repo)
            return _dorebase(ui, repo, action, opts, inmemory=False)
    else:
        return _dorebase(ui, repo, action, opts)


def _dryrunrebase(ui, repo, action, opts):
    rbsrt = rebaseruntime(repo, ui, inmemory=True, opts=opts)
    confirm = opts.get('confirm')
    if confirm:
        ui.status(_('starting in-memory rebase\n'))
    else:
        ui.status(
            _('starting dry-run rebase; repository will not be ' 'changed\n')
        )
    with repo.wlock(), repo.lock():
        needsabort = True
        try:
            overrides = {('rebase', 'singletransaction'): True}
            with ui.configoverride(overrides, 'rebase'):
                _origrebase(
                    ui,
                    repo,
                    action,
                    opts,
                    rbsrt,
                    inmemory=True,
                    leaveunfinished=True,
                )
        except error.InMemoryMergeConflictsError:
            ui.status(_('hit a merge conflict\n'))
            return 1
        except error.Abort:
            needsabort = False
            raise
        else:
            if confirm:
                ui.status(_('rebase completed successfully\n'))
                if not ui.promptchoice(
                    _(b'apply changes (yn)?' b'$$ &Yes $$ &No')
                ):
                    # finish unfinished rebase
                    rbsrt._finishrebase()
                else:
                    rbsrt._prepareabortorcontinue(
                        isabort=True, backup=False, suppwarns=True
                    )
                needsabort = False
            else:
                ui.status(
                    _(
                        'dry-run rebase completed successfully; run without'
                        ' -n/--dry-run to perform this rebase\n'
                    )
                )
            return 0
        finally:
            if needsabort:
                # no need to store backup in case of dryrun
                rbsrt._prepareabortorcontinue(
                    isabort=True, backup=False, suppwarns=True
                )


def _dorebase(ui, repo, action, opts, inmemory=False):
    rbsrt = rebaseruntime(repo, ui, inmemory, opts)
    return _origrebase(ui, repo, action, opts, rbsrt, inmemory=inmemory)


def _origrebase(
    ui, repo, action, opts, rbsrt, inmemory=False, leaveunfinished=False
):
    assert action != 'stop'
    with repo.wlock(), repo.lock():
        # Validate input and define rebasing points
        destf = opts.get('dest', None)
        srcf = opts.get('source', None)

                if extensions.find('histedit'):
                    enablehistedit = ''
            except KeyError:
                enablehistedit = " --config extensions.histedit="
            help = "hg%s help -e histedit" % enablehistedit
            msg = (
                _(
                    "interactive history editing is supported by the "
                    "'histedit' extension (see \"%s\")"
                )
                % help
            )
            raise error.Abort(msg)

        if rbsrt.collapsemsg and not rbsrt.collapsef:
            raise error.Abort(_('message can only be specified with collapse'))

        if action:
            if rbsrt.collapsef:
                raise error.Abort(
                    _('cannot use collapse with continue or abort')
                )
            if srcf or basef or destf:
                raise error.Abort(
                    _('abort and continue do not allow specifying revisions')
                )
            if action == 'abort' and opts.get('tool', False):
                ui.warn(_('tool option will be ignored\n'))
            if action == 'continue':
                ms = mergemod.mergestate.read(repo)
                mergeutil.checkunresolved(ms)

            retcode = rbsrt._prepareabortorcontinue(isabort=(action == 'abort'))
            if retcode is not None:
                return retcode
        else:
            destmap = _definedestmap(
                ui,
                repo,
                inmemory,
                destf,
                srcf,
                basef,
                revf,
                destspace=destspace,
            )
            retcode = rbsrt._preparenewrebase(destmap)
            if retcode is not None:
                return retcode
            storecollapsemsg(repo, rbsrt.collapsemsg)

            with util.acceptintervention(dsguard):
                rbsrt._performrebase(tr)
                if not leaveunfinished:
                    rbsrt._finishrebase()


def _definedestmap(
    ui,
    repo,
    inmemory,
    destf=None,
    srcf=None,
    basef=None,
    revf=None,
    destspace=None,
):
    """use revisions argument to define destmap {srcrev: destrev}"""
    if revf is None:
        revf = []

    # destspace is here to work around issues with `hg pull --rebase` see

    if not inmemory:
        cmdutil.checkunfinished(repo)
        cmdutil.bailifchanged(repo)

    if ui.configbool('commands', 'rebase.requiredest') and not destf:
        raise error.Abort(
            _('you must specify a destination'), hint=_('use: hg rebase -d REV')
        )

    dest = None

    if revf:
        rebaseset = scmutil.revrange(repo, revf)

        rebaseset = repo.revs('(%ld)::', src)
        assert rebaseset
    else:
        base = scmutil.revrange(repo, [basef or '.'])
        if not base:
            ui.status(
                _('empty "base" revision set - ' "can't compute rebase set\n")
            )
            return None
        if destf:
            # --base does not support multiple destinations
            dest = scmutil.revsingle(repo, destf)
        else:
            dest = repo[_destrebase(repo, base, destspace=destspace)]
            destf = bytes(dest)

        roots = []  # selected children of branching points
        bpbase = {}  # {branchingpoint: [origbase]}
        for b in base:  # group bases by branching points
            bp = repo.revs('ancestor(%d, %d)', b, dest.rev()).first()
            bpbase[bp] = bpbase.get(bp, []) + [b]
        if None in bpbase:
            # emulate the old behavior, showing "nothing to rebase" (a better
            # behavior may be abort with "cannot find branching point" error)
            bpbase.clear()
        for bp, bs in bpbase.iteritems():  # calculate roots
            roots += list(repo.revs('children(%d) & ancestors(%ld)', bp, bs))

        rebaseset = repo.revs('%ld::', roots)

        if not rebaseset:
            # transform to list because smartsets are not comparable to
            # lists. This should be improved to honor laziness of
            # smartset.
            if list(base) == [dest.rev()]:
                if basef:
                    ui.status(
                        _(
                            'nothing to rebase - %s is both "base"'
                            ' and destination\n'
                        )
                        % dest
                    )
                else:
                    ui.status(
                        _(
                            'nothing to rebase - working directory '
                            'parent is also destination\n'
                        )
                    )
            elif not repo.revs('%ld - ::%d', base, dest.rev()):
                if basef:
                    ui.status(
                        _(
                            'nothing to rebase - "base" %s is '
                            'already an ancestor of destination '
                            '%s\n'
                        )
                        % ('+'.join(bytes(repo[r]) for r in base), dest)
                    )
                else:
                    ui.status(
                        _(
                            'nothing to rebase - working '
                            'directory parent is already an '
                            'ancestor of destination %s\n'
                        )
                        % dest
                    )
            else:  # can it happen?
                ui.status(
                    _('nothing to rebase from %s to %s\n')
                    % ('+'.join(bytes(repo[r]) for r in base), dest)
                )
            return None

    rebasingwcp = repo['.'].rev() in rebaseset
    ui.log(
        "rebase",
        "rebasing working copy parent: %r\n",
        rebasingwcp,
        rebase_rebasing_wcp=rebasingwcp,
    )
    if inmemory and rebasingwcp:
        # Check these since we did not before.
        cmdutil.checkunfinished(repo)
        cmdutil.bailifchanged(repo)

                if size == 1:
                    destmap[r] = destset.first()
                elif size == 0:
                    ui.note(_('skipping %s - empty destination\n') % repo[r])
                else:
                    raise error.Abort(
                        _('rebase destination for %s is not ' 'unique')
                        % repo[r]
                    )

    if dest is not None:
        # single-dest case: assign dest to each rev in rebaseset
        destrev = dest.rev()
        destmap = {r: destrev for r in rebaseset}  # {srcrev: destrev}

    if not destmap:
        ui.status(_('nothing to rebase - empty destination\n'))
        return None

    return destmap


def externalparent(repo, state, destancestors):
    """Return the revision that should be used as the second parent
    when the revisions in state is collapsed on top of destancestors.
    Abort if there is more than one parent.

    source = min(state)
    for rev in state:
        if rev == source:
            continue
        for p in repo[rev].parents():
            if p.rev() not in state and p.rev() not in destancestors:
                parents.add(p.rev())
    if not parents:
        return nullrev
    if len(parents) == 1:
        return parents.pop()
    raise error.Abort(
        _(
            'unable to collapse on top of %d, there is more '
            'than one external parent: %s'
        )
        % (max(destancestors), ', '.join("%d" % p for p in sorted(parents)))
    )


def commitmemorynode(repo, p1, p2, wctx, editor, extra, user, date, commitmsg):
    '''Commit the memory changes with parents p1 and p2.
    Return node of committed revision.'''
    # Replicates the empty check in ``repo.commit``.

    # ``branch`` (used when passing ``--keepbranches``).
    branch = repo[p1].branch()
    if 'branch' in extra:
        branch = extra['branch']

    memctx = wctx.tomemctx(
        commitmsg,
        parents=(p1, p2),
        date=date,
        extra=extra,
        user=user,
        branch=branch,
        editor=editor,
    )
    commitres = repo.commitctx(memctx)
    wctx.clean()  # Might be reused
    return commitres


def commitnode(repo, p1, p2, editor, extra, user, date, commitmsg):
    '''Commit the wd changes with parents p1 and p2.
    Return node of committed revision.'''
    dsguard = util.nullcontextmanager()

        dsguard = dirstateguard.dirstateguard(repo, 'rebase')
    with dsguard:
        repo.setparents(repo[p1].node(), repo[p2].node())

        # Commit might fail if unresolved files exist
        newnode = repo.commit(
            text=commitmsg, user=user, date=date, extra=extra, editor=editor
        )

        repo.dirstate.setbranch(repo[newnode].branch())
        return newnode


def rebasenode(repo, rev, p1, base, collapse, dest, wctx):
    'Rebase a single revision rev on top of p1 using base as merge ancestor'
    # Merge phase
    # Update to destination and merge it with local

    repo.ui.debug(" merge against %d:%s\n" % (rev, repo[rev]))
    if base is not None:
        repo.ui.debug("   detach base %d:%s\n" % (base, repo[base]))
    # When collapsing in-place, the parent is the common ancestor, we
    # have to allow merging with it.
    stats = mergemod.update(
        repo,
        rev,
        branchmerge=True,
        force=True,
        ancestor=base,
        mergeancestor=collapse,
        labels=['dest', 'source'],
        wc=wctx,
    )
    if collapse:
        copies.duplicatecopies(repo, wctx, rev, dest)
    else:
        # If we're not using --collapse, we need to
        # duplicate copies between the revision we're

        # duplicate any copies that have already been
        # performed in the destination.
        p1rev = repo[rev].p1().rev()
        copies.duplicatecopies(repo, wctx, rev, p1rev, skiprev=dest)
    return stats


def adjustdest(repo, rev, destmap, state, skipped):
    r"""adjust rebase destination given the current rebase state

    rev is what is being rebased. Return a list of two revs, which are the

       \ /
        A
    """
    # pick already rebased revs with same dest from state as interesting source
    dest = destmap[rev]
    source = [
        s
        for s, d in state.items()
        if d > 0 and destmap[s] == dest and s not in skipped
    ]

    result = []
    for prev in repo.changelog.parentrevs(rev):
        adjusted = dest
        if prev != nullrev:

        if adjusted == dest and dest in state:
            adjusted = state[dest]
            if adjusted == revtodo:
                # sortsource should produce an order that makes this impossible
                raise error.ProgrammingError(
                    'rev %d should be rebased already at this time' % dest
                )
        result.append(adjusted)
    return result


def _checkobsrebase(repo, ui, rebaseobsrevs, rebaseobsskipped):
    """
    Abort if rebase will create divergence or rebase is noop because of markers

    `rebaseobsrevs`: set of obsolete revision in source
    `rebaseobsskipped`: set of revisions from source skipped because they have
    successors in destination or no non-obsolete successor.
    """
    # Obsolete node with successors not in dest leads to divergence
    divergenceok = ui.configbool('experimental', 'evolution.allowdivergence')
    divergencebasecandidates = rebaseobsrevs - rebaseobsskipped

    if divergencebasecandidates and not divergenceok:
        divhashes = (bytes(repo[r]) for r in divergencebasecandidates)
        msg = _("this rebase will cause " "divergences from: %s")
        h = _(
            "to force the rebase please set "
            "experimental.evolution.allowdivergence=True"
        )
        raise error.Abort(msg % (",".join(divhashes),), hint=h)


def successorrevs(unfi, rev):
    """yield revision numbers for successors of rev"""
    assert unfi.filtername is None
    nodemap = unfi.changelog.nodemap
    for s in obsutil.allsuccessors(unfi.obsstore, [unfi[rev].node()]):
        if s in nodemap:
            yield nodemap[s]


def defineparents(repo, rev, destmap, state, skipped, obsskipped):
    """Return new parents and optionally a merge base for rev being rebased

    The destination specified by "dest" cannot always be used directly because
    previously rebase result could affect destination. For example,

    assert repo.filtername is None
    cl = repo.changelog
    isancestor = cl.isancestorrev

    dest = destmap[rev]
    oldps = repo.changelog.parentrevs(rev)  # old parents
    newps = [nullrev, nullrev]  # new parents
    dests = adjustdest(repo, rev, destmap, state, skipped)
    bases = list(oldps)  # merge base candidates, initially just old parents

    if all(r == nullrev for r in oldps[1:]):
        # For non-merge changeset, just move p to adjusted dest as requested.
        newps[0] = dests[0]
    else:

        #   A B D  # B (using rule "2."), since B will be rebased.
        #
        # The loop tries to be not rely on the fact that a Mercurial node has
        # at most 2 parents.
        for i, p in enumerate(oldps):
            np = p  # new parent
            if any(isancestor(x, dests[i]) for x in successorrevs(repo, p)):
                np = dests[i]
            elif p in state and state[p] > 0:
                np = state[p]

            # If one parent becomes an ancestor of the other, drop the ancestor
            for j, x in enumerate(newps[:i]):
                if x == nullrev:
                    continue
                if isancestor(np, x):  # CASE-1
                    np = nullrev
                elif isancestor(x, np):  # CASE-2
                    newps[j] = np
                    np = nullrev
                    # New parents forming an ancestor relationship does not
                    # mean the old parents have a similar relationship. Do not
                    # set bases[x] to nullrev.

        #
        #     C    # rebase -r C -d D
        #    /|    # None of A and B will be changed to D and rebase fails.
        #   A B D
        if set(newps) == set(oldps) and dest not in newps:
            raise error.Abort(
                _(
                    'cannot rebase %d:%s without '
                    'moving at least one of its parents'
                )
                % (rev, repo[rev])
            )

    # Source should not be ancestor of dest. The check here guarantees it's
    # impossible. With multi-dest, the initial check does not cover complex
    # cases since we don't have abstractions to dry-run rebase cheaply.
    if any(p != nullrev and isancestor(rev, p) for p in newps):

    #
    # But our merge base candidates (D and E in above case) could still be
    # better than the default (ancestor(F, Z) == null). Therefore still
    # pick one (so choose p1 above).
    if sum(1 for b in bases if b != nullrev) > 1:
        unwanted = [None, None]  # unwanted[i]: unwanted revs if choose bases[i]
        for i, base in enumerate(bases):
            if base == nullrev:
                continue
            # Revisions in the side (not chosen as merge base) branch that
            # might contain "surprising" contents
            siderevs = list(
                repo.revs('((%ld-%d) %% (%d+%d))', bases, base, base, dest)
            )

            # If those revisions are covered by rebaseset, the result is good.
            # A merge in rebaseset would be considered to cover its ancestors.
            if siderevs:
                rebaseset = [
                    r for r, d in state.items() if d > 0 and r not in obsskipped
                ]
                merges = [
                    r for r in rebaseset if cl.parentrevs(r)[1] != nullrev
                ]
                unwanted[i] = list(
                    repo.revs(
                        '%ld - (::%ld) - %ld', siderevs, merges, rebaseset
                    )
                )

        # Choose a merge base that has a minimal number of unwanted revs.
        l, i = min(
            (len(revs), i)
            for i, revs in enumerate(unwanted)
            if revs is not None
        )
        base = bases[i]

        # newps[0] should match merge base if possible. Currently, if newps[i]
        # is nullrev, the only case is newps[i] and newps[j] (j < i), one is
        # the other's ancestor. In that case, it's fine to not swap newps here.

        # The merge will include unwanted revisions. Abort now. Revisit this if
        # we have a more advanced merge algorithm that handles multiple bases.
        if l > 0:
            unwanteddesc = _(' or ').join(
                (
                    ', '.join('%d:%s' % (r, repo[r]) for r in revs)
                    for revs in unwanted
                    if revs is not None
                )
            )
            raise error.Abort(
                _('rebasing %d:%s will include unwanted changes from %s')
                % (rev, repo[rev], unwanteddesc)
            )

    repo.ui.debug(" future parents are %d and %d\n" % tuple(newps))

    return newps[0], newps[1], base


def isagitpatch(repo, patchname):
    'Return true if the given patch is in git format'
    mqpatch = os.path.join(repo.mq.path, patchname)
    for line in patch.linereader(open(mqpatch, 'rb')):
        if line.startswith('diff --git'):
            return True
    return False


def updatemq(repo, state, skipped, **opts):
    'Update rebased mq patches - finalize and then import them'
    mqrebase = {}
    mq = repo.mq
    original_series = mq.fullseries[:]
    skippedpatches = set()

    for p in mq.applied:
        rev = repo[p.node].rev()
        if rev in state:
            repo.ui.debug(
                'revision %d is an mq patch (%s), finalize it.\n'
                % (rev, p.name)
            )
            mqrebase[rev] = (p.name, isagitpatch(repo, p.name))
        else:
            # Applied but not rebased, not sure this should happen
            skippedpatches.add(p.name)

        # We must start import from the newest revision
        for rev in sorted(mqrebase, reverse=True):
            if rev not in skipped:
                name, isgit = mqrebase[rev]
                repo.ui.note(
                    _('updating mq patch %s to %d:%s\n')
                    % (name, state[rev], repo[state[rev]])
                )
                mq.qimport(
                    repo, (), patchname=name, git=isgit, rev=["%d" % state[rev]]
                )
            else:
                # Rebased and skipped
                skippedpatches.add(mqrebase[rev][0])

        # Patches were either applied and rebased and imported in
        # order, applied and removed or unapplied. Discard the removed
        # ones while preserving the original series order and guards.
        newseries = [
            s
            for s in original_series
            if mq.guard_re.split(s, 1)[0] not in skippedpatches
        ]
        mq.fullseries[:] = newseries
        mq.seriesdirty = True
        mq.savedirty()


def storecollapsemsg(repo, collapsemsg):
    'Store the collapse message to allow recovery'
    collapsemsg = collapsemsg or ''
    f = repo.vfs("last-message.txt", "w")
    f.write("%s\n" % collapsemsg)
    f.close()


def clearcollapsemsg(repo):
    'Remove collapse message file'
    repo.vfs.unlinkpath("last-message.txt", ignoremissing=True)


def restorecollapsemsg(repo, isabort):
    'Restore previously stored collapse message'
    try:
        f = repo.vfs("last-message.txt")

            collapsemsg = ''
        else:
            raise error.Abort(_('missing .hg/last-message.txt for rebase'))
    return collapsemsg


def clearstatus(repo):
    'Remove the status files'
    # Make sure the active transaction won't write the state file
    tr = repo.currenttransaction()
    if tr:
        tr.removefilegenerator('rebasestate')
    repo.vfs.unlinkpath("rebasestate", ignoremissing=True)


def needupdate(repo, state):
    '''check whether we should `update --clean` away from a merge, or if
    somehow the working dir got forcibly updated, e.g. by older hg'''
    parents = [p.rev() for p in repo[None].parents()]

    # Are we in a merge state at all?
    if len(parents) < 2:
        return False

    # We should be standing on the first as-of-yet unrebased commit.
    firstunrebased = min(
        [old for old, new in state.iteritems() if new == nullrev]
    )
    if firstunrebased in parents:
        return True

    return False


def sortsource(destmap):
    """yield source revisions in an order that we only rebase things once

    If source and destination overlaps, we should filter out revisions

        if not result:
            raise error.Abort(_('source and destination form a cycle'))
        srcset -= set(result)
        yield result


def buildstate(repo, destmap, collapse):
    '''Define which revisions are going to be rebased and where

    repo: repo
    destmap: {srcrev: destrev}

        mqapplied = set(repo[s.node].rev() for s in repo.mq.applied)
        if set(destmap.values()) & mqapplied:
            raise error.Abort(_('cannot rebase onto an applied mq patch'))

    # Get "cycle" error early by exhausting the generator.
    sortedsrc = list(sortsource(destmap))  # a list of sorted revs
    if not sortedsrc:
        raise error.Abort(_('no matching revisions'))

    # Only check the first batch of revisions to rebase not depending on other
    # rebaseset. This means "source is ancestor of destination" for the second
    # (and following) batches of revisions are not checked here. We rely on
    # "defineparents" to do that check.
    roots = list(repo.set('roots(%ld)', sortedsrc[0]))
    if not roots:
        raise error.Abort(_('no matching revisions'))

    def revof(r):
        return r.rev()

    roots = sorted(roots, key=revof)
    state = dict.fromkeys(rebaseset, revtodo)
    emptyrebase = len(sortedsrc) == 1
    for root in roots:
        dest = repo[destmap[root.rev()]]
        commonbase = root.ancestor(dest)
        if commonbase == root:
            raise error.Abort(_('source is ancestor of destination'))

        # if all parents of this revision are done, then so is this revision
        if parents and all((state.get(p) == p for p in parents)):
            state[rev] = rev
    return originalwd, destmap, state


def clearrebased(
    ui,
    repo,
    destmap,
    state,
    skipped,
    collapsedas=None,
    keepf=False,
    fm=None,
    backup=True,
):
    """dispose of rebased revision at the end of the rebase

    If `collapsedas` is not None, the rebase was a collapse whose result if the
    `collapsedas` node.

        fm.data(nodechanges=nodechanges)
    if keepf:
        replacements = {}
    scmutil.cleanupnodes(repo, replacements, 'rebase', moves, backup=backup)


def pullrebase(orig, ui, repo, *args, **opts):
    'Call rebase after pull if the latter has been invoked with --rebase'
    if opts.get(r'rebase'):
        if ui.configbool('commands', 'rebase.requiredest'):
            msg = _('rebase destination required by configuration')

            raise error.Abort(msg, hint=hint)

        with repo.wlock(), repo.lock():
            if opts.get(r'update'):
                del opts[r'update']
                ui.debug(
                    '--update and --rebase are not compatible, ignoring '
                    'the update flag\n'
                )

            cmdutil.checkunfinished(repo, skipmerge=True)
            cmdutil.bailifchanged(
                repo,
                hint=_(
                    'cannot pull with rebase: '
                    'please commit or shelve your changes first'
                ),
            )

            revsprepull = len(repo)
            origpostincoming = commands.postincoming

            def _dummy(*args, **kwargs):
                pass

            commands.postincoming = _dummy
            try:
                ret = orig(ui, repo, *args, **opts)
            finally:
                commands.postincoming = origpostincoming

            raise error.Abort(_('--tool can only be used with --rebase'))
        ret = orig(ui, repo, *args, **opts)

    return ret


def _filterobsoleterevs(repo, revs):
    """returns a set of the obsolete revisions in revs"""
    return set(r for r in revs if repo[r].obsolete())


def _computeobsoletenotrebased(repo, rebaseobsrevs, destmap):
    """Return (obsoletenotrebased, obsoletewithoutsuccessorindestination).

    `obsoletenotrebased` is a mapping mapping obsolete => successor for all

        obsoletenotrebased,
        obsoletewithoutsuccessorindestination,
        obsoleteextinctsuccessors,
    )


def abortrebase(ui, repo):
    with repo.wlock(), repo.lock():
        rbsrt = rebaseruntime(repo, ui)
        rbsrt._prepareabortorcontinue(isabort=True)


def continuerebase(ui, repo):
    with repo.wlock(), repo.lock():
        rbsrt = rebaseruntime(repo, ui)
        ms = mergemod.mergestate.read(repo)

        retcode = rbsrt._prepareabortorcontinue(isabort=False)
        if retcode is not None:
            return retcode
        rbsrt._performrebase(None)
        rbsrt._finishrebase()


def summaryhook(ui, repo):
    if not repo.vfs.exists('rebasestate'):
        return
    try:

        msg = _('rebase: (use "hg rebase --abort" to clear broken state)\n')
        ui.write(msg)
        return
    numrebased = len([i for i in state.itervalues() if i >= 0])
    # i18n: column positioning for "hg summary"
    ui.write(
        _('rebase: %s, %s (rebase --continue)\n')
        % (
            ui.label(_('%d rebased'), 'rebase.rebased') % numrebased,
            ui.label(_('%d remaining'), 'rebase.remaining')
            % (len(state) - numrebased),
        )
    )


def uisetup(ui):
    # Replace pull with a decorator to provide --rebase option
    entry = extensions.wrapcommand(commands.table, 'pull', pullrebase)
    entry[1].append(
        ('', 'rebase', None, _("rebase working directory to branch head"))
    )
    entry[1].append(('t', 'tool', '', _("specify merge tool for rebase")))
    cmdutil.summaryhooks.add('rebase', summaryhook)
    statemod.addunfinished(
        'rebase',
        fname='rebasestate',
        stopflag=True,
        continueflag=True,
        abortfunc=abortrebase,
        continuefunc=continuerebase,
    )