def pullrebaseif(orig, ui, repo, *args, **opts):
    '''Call rebaseif after pull if the latter has been invoked with --rebaseif'''
    # this function is taken in verbatim from rebase extension, with rebase replaced with rebaseif

    if opts.get('rebaseif'):
        if opts.get('update'):
            del opts['update']
            ui.debug(_('--update and --rebaseif are not compatible, ignoring the update flag\n'))

        try:
            cmdutil.bailifchanged(repo) # 1.9
        except AttributeError:
            cmdutil.bail_if_changed(repo) # < 1.9

        revsprepull = len(repo)
        origpostincoming = commands.postincoming
        def _dummy(*args, **kwargs):
            pass
        commands.postincoming = _dummy
        try:
            orig(ui, repo, *args, **opts)
        finally:
            commands.postincoming = origpostincoming
        revspostpull = len(repo)
        if revspostpull > revsprepull:
            rebaseif(ui, repo, **opts)
            branch = repo[None].branch()
            dest = repo[branch].rev()
            if dest != repo['.'].rev():
                # there was nothing to rebase we force an update
                hg.update(repo, dest)
    else:
        orig(ui, repo, *args, **opts)

def pullrebase(orig, ui, repo, *args, **opts):
    'Call rebase after pull if the latter has been invoked with --rebase'
    if opts.get('rebase'):
        if opts.get('update'):
            del opts['update']
            ui.debug('--update and --rebase are not compatible, ignoring '
                     'the update flag\n')

        cmdutil.bailifchanged(repo)
        revsprepull = len(repo)
        origpostincoming = commands.postincoming
        def _dummy(*args, **kwargs):
            pass
        commands.postincoming = _dummy
        try:
            orig(ui, repo, *args, **opts)
        finally:
            commands.postincoming = origpostincoming
        revspostpull = len(repo)
        if revspostpull > revsprepull:
            rebase(ui, repo, **opts)
            branch = repo[None].branch()
            dest = repo[branch].rev()
            if dest != repo['.'].rev():
                # there was nothing to rebase we force an update
                hg.update(repo, dest)
    else:
        if opts.get('tool'):
            raise util.Abort(_('--tool can only be used with --rebase'))
        orig(ui, repo, *args, **opts)

def override_pull(orig, ui, repo, source=None, **opts):
    if opts.get('rebase', False):
        repo._isrebasing = True
        try:
            if opts.get('update'):
                 del opts['update']
                 ui.debug('--update and --rebase are not compatible, ignoring '
                          'the update flag\n')
            del opts['rebase']
            cmdutil.bailifchanged(repo)
            revsprepull = len(repo)
            origpostincoming = commands.postincoming
            def _dummy(*args, **kwargs):
                pass
            commands.postincoming = _dummy
            repo.lfpullsource = source
            if not source:
                source = 'default'
            try:
                result = commands.pull(ui, repo, source, **opts)
            finally:
                commands.postincoming = origpostincoming
            revspostpull = len(repo)
            if revspostpull > revsprepull:
                result = result or rebase.rebase(ui, repo)
        finally:
            repo._isrebasing = False
    else:
        repo.lfpullsource = source
        if not source:
            source = 'default'
        result = orig(ui, repo, source, **opts)
    return result

def verify_pending_commits(repo):
    """
    Checks if there are any pending uncommitted changese

    Args:
        repo - the current repository
    """
    cmdutil.bailifchanged(repo)

def hide(ui, repo, *revs, **opts):
    """hide changesets and their descendants

    Hidden changesets are still accessible by their hashes which can be found
    in ``hg journal``.

    If a parent of the working directory is hidden, then the working directory
    will automatically be updated to the most recent available ancestor of the
    hidden parent.

    If there is a bookmark pointing to the commit it will be removed.
    """
    revs = list(revs) + opts.pop('rev', [])
    revs = set(scmutil.revrange(repo, revs))
    hidectxs = list(repo.set("(%ld)::", revs))

    if not hidectxs:
        raise error.Abort(_('nothing to hide'))

    with repo.wlock(), repo.lock(), repo.transaction('hide') as tr:
        # revs to be hidden
        for ctx in hidectxs:
            if not ctx.mutable():
                raise error.Abort(
                    _('cannot hide immutable changeset: %s') % ctx,
                    hint="see 'hg help phases' for details")

        wdp = repo['.']
        newnode = wdp

        while newnode in hidectxs:
            newnode = newnode.parents()[0]

        if newnode.node() != wdp.node():
            cmdutil.bailifchanged(repo, merge=False)
            hg.update(repo, newnode, False)
            ui.status(_('working directory now at %s\n')
                      % ui.label(str(newnode), 'node'))

        # create markers
        obsolete.createmarkers(repo, [(r, []) for r in hidectxs],
                               operation='hide')
        ui.status(_('%i changesets hidden\n') % len(hidectxs))

        # remove bookmarks pointing to hidden changesets
        hnodes = [r.node() for r in hidectxs]
        bmchanges = []
        for book, node in bookmarksmod.listbinbookmarks(repo):
            if node in hnodes:
                bmchanges.append((book, None))
        repo._bookmarks.applychanges(repo, tr, bmchanges)

        if len(bmchanges) > 0:
            ui.status(_('%i bookmarks removed\n') % len(bmchanges))

def override_pull(orig, ui, repo, source=None, **opts):
    if opts.get("rebase", False):
        repo._isrebasing = True
        try:
            if opts.get("update"):
                del opts["update"]
                ui.debug("--update and --rebase are not compatible, ignoring " "the update flag\n")
            del opts["rebase"]
            cmdutil.bailifchanged(repo)
            revsprepull = len(repo)
            origpostincoming = commands.postincoming

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

            commands.postincoming = _dummy
            repo.lfpullsource = source
            if not source:
                source = "default"
            try:
                result = commands.pull(ui, repo, source, **opts)
            finally:
                commands.postincoming = origpostincoming
            revspostpull = len(repo)
            if revspostpull > revsprepull:
                result = result or rebase.rebase(ui, repo)
        finally:
            repo._isrebasing = False
    else:
        repo.lfpullsource = source
        if not source:
            source = "default"
        oldheads = lfutil.getcurrentheads(repo)
        result = orig(ui, repo, source, **opts)
        # If we do not have the new largefiles for any new heads we pulled, we
        # will run into a problem later if we try to merge or rebase with one of
        # these heads, so cache the largefiles now direclty into the system
        # cache.
        ui.status(_("caching new largefiles\n"))
        numcached = 0
        heads = lfutil.getcurrentheads(repo)
        newheads = set(heads).difference(set(oldheads))
        for head in newheads:
            (cached, missing) = lfcommands.cachelfiles(ui, repo, head)
            numcached += len(cached)
        ui.status(_("%d largefiles cached\n") % numcached)
    return result

def override_pull(orig, ui, repo, source=None, **opts):
    if opts.get('rebase', False):
        repo._isrebasing = True
        try:
            if opts.get('update'):
                 del opts['update']
                 ui.debug('--update and --rebase are not compatible, ignoring '
                          'the update flag\n')
            del opts['rebase']
            cmdutil.bailifchanged(repo)
            revsprepull = len(repo)
            origpostincoming = commands.postincoming
            def _dummy(*args, **kwargs):
                pass
            commands.postincoming = _dummy
            repo.lfpullsource = source
            if not source:
                source = 'default'
            try:
                result = commands.pull(ui, repo, source, **opts)
            finally:
                commands.postincoming = origpostincoming
            revspostpull = len(repo)
            if revspostpull > revsprepull:
                result = result or rebase.rebase(ui, repo)
        finally:
            repo._isrebasing = False
    else:
        repo.lfpullsource = source
        if not source:
            source = 'default'
        result = orig(ui, repo, source, **opts)
        # If we do not have the new largefiles for any new heads we pulled, we
        # will run into a problem later if we try to merge or rebase with one of
        # these heads, so cache the largefiles now direclty into the system
        # cache.
        ui.status(_("caching new largefiles\n"))
        numcached = 0
        branches = repo.branchmap()
        for branch in branches:
            heads = repo.branchheads(branch)
            for head in heads:
                (cached, missing) = lfcommands.cachelfiles(ui, repo, head)
                numcached += len(cached)
        ui.status(_("%d largefiles cached\n" % numcached))
    return result

def overridepull(orig, ui, repo, source=None, **opts):
    revsprepull = len(repo)
    if not source:
        source = 'default'
    repo.lfpullsource = source
    if opts.get('rebase', False):
        repo._isrebasing = True
        try:
            if opts.get('update'):
                del opts['update']
                ui.debug('--update and --rebase are not compatible, ignoring '
                         'the update flag\n')
            del opts['rebase']
            cmdutil.bailifchanged(repo)
            origpostincoming = commands.postincoming
            def _dummy(*args, **kwargs):
                pass
            commands.postincoming = _dummy
            try:
                result = commands.pull(ui, repo, source, **opts)
            finally:
                commands.postincoming = origpostincoming
            revspostpull = len(repo)
            if revspostpull > revsprepull:
                result = result or rebase.rebase(ui, repo)
        finally:
            repo._isrebasing = False
    else:
        result = orig(ui, repo, source, **opts)
    revspostpull = len(repo)
    lfrevs = opts.get('lfrev', [])
    if opts.get('all_largefiles'):
        lfrevs.append('pulled()')
    if lfrevs and revspostpull > revsprepull:
        numcached = 0
        repo.firstpulled = revsprepull # for pulled() revset expression
        try:
            for rev in scmutil.revrange(repo, lfrevs):
                ui.note(_('pulling largefiles for revision %s\n') % rev)
                (cached, missing) = lfcommands.cachelfiles(ui, repo, rev)
                numcached += len(cached)
        finally:
            del repo.firstpulled
        ui.status(_("%d largefiles cached\n") % numcached)
    return result

def pullrebase(orig, ui, repo, *args, **opts):
    'Call rebase after pull if the latter has been invoked with --rebase'
    if opts.get('rebase'):
        if opts.get('update'):
            del opts['update']
            ui.debug('--update and --rebase are not compatible, ignoring '
                     'the update flag\n')

        movemarkfrom = repo['.'].node()
        cmdutil.bailifchanged(repo)
        revsprepull = len(repo)
        origpostincoming = commands.postincoming
        def _dummy(*args, **kwargs):
            pass
        commands.postincoming = _dummy
        try:
            orig(ui, repo, *args, **opts)
        finally:
            commands.postincoming = origpostincoming
        revspostpull = len(repo)
        if revspostpull > revsprepull:
            # --rev option from pull conflict with rebase own --rev
            # dropping it
            if 'rev' in opts:
                del opts['rev']
            rebase(ui, repo, **opts)
            branch = repo[None].branch()
            dest = repo[branch].rev()
            if dest != repo['.'].rev():
                # there was nothing to rebase we force an update
                hg.update(repo, dest)
                if bookmarks.update(repo, [movemarkfrom], repo['.'].node()):
                    ui.status(_("updating bookmark %s\n")
                              % repo._bookmarkcurrent)
    else:
        if opts.get('tool'):
            raise util.Abort(_('--tool can only be used with --rebase'))
        orig(ui, repo, *args, **opts)

def _histedit(ui, repo, *freeargs, **opts):
    # TODO only abort if we try and histedit mq patches, not just
    # blanket if mq patches are applied somewhere
    mq = getattr(repo, 'mq', None)
    if mq and mq.applied:
        raise util.Abort(_('source has mq patches applied'))

    # basic argument incompatibility processing
    outg = opts.get('outgoing')
    cont = opts.get('continue')
    abort = opts.get('abort')
    force = opts.get('force')
    rules = opts.get('commands', '')
    revs = opts.get('rev', [])
    goal = 'new' # This invocation goal, in new, continue, abort
    if force and not outg:
        raise util.Abort(_('--force only allowed with --outgoing'))
    if cont:
        if util.any((outg, abort, revs, freeargs, rules)):
            raise util.Abort(_('no arguments allowed with --continue'))
        goal = 'continue'
    elif abort:
        if util.any((outg, revs, freeargs, rules)):
            raise util.Abort(_('no arguments allowed with --abort'))
        goal = 'abort'
    else:
        if os.path.exists(os.path.join(repo.path, 'histedit-state')):
            raise util.Abort(_('history edit already in progress, try '
                               '--continue or --abort'))
        if outg:
            if revs:
                raise util.Abort(_('no revisions allowed with --outgoing'))
            if len(freeargs) > 1:
                raise util.Abort(
                    _('only one repo argument allowed with --outgoing'))
        else:
            revs.extend(freeargs)
            if len(revs) != 1:
                raise util.Abort(
                    _('histedit requires exactly one ancestor revision'))


    if goal == 'continue':
        (parentctxnode, rules, keep, topmost, replacements) = readstate(repo)
        parentctx = repo[parentctxnode]
        parentctx, repl = bootstrapcontinue(ui, repo, parentctx, rules, opts)
        replacements.extend(repl)
    elif goal == 'abort':
        (parentctxnode, rules, keep, topmost, replacements) = readstate(repo)
        mapping, tmpnodes, leafs, _ntm = processreplacement(repo, replacements)
        ui.debug('restore wc to old parent %s\n' % node.short(topmost))
        # check whether we should update away
        parentnodes = [c.node() for c in repo[None].parents()]
        for n in leafs | set([parentctxnode]):
            if n in parentnodes:
                hg.clean(repo, topmost)
                break
        else:
            pass
        cleanupnode(ui, repo, 'created', tmpnodes)
        cleanupnode(ui, repo, 'temp', leafs)
        os.unlink(os.path.join(repo.path, 'histedit-state'))
        return
    else:
        cmdutil.checkunfinished(repo)
        cmdutil.bailifchanged(repo)

        topmost, empty = repo.dirstate.parents()
        if outg:
            if freeargs:
                remote = freeargs[0]
            else:
                remote = None
            root = findoutgoing(ui, repo, remote, force, opts)
        else:
            rootrevs = list(repo.set('roots(%lr)', revs))
            if len(rootrevs) != 1:
                raise util.Abort(_('The specified revisions must have '
                    'exactly one common root'))
            root = rootrevs[0].node()

        keep = opts.get('keep', False)
        revs = between(repo, root, topmost, keep)
        if not revs:
            raise util.Abort(_('%s is not an ancestor of working directory') %
                             node.short(root))

        ctxs = [repo[r] for r in revs]
        if not rules:
            rules = '\n'.join([makedesc(c) for c in ctxs])
            rules += '\n\n'
            rules += editcomment % (node.short(root), node.short(topmost))
            rules = ui.edit(rules, ui.username())
            # Save edit rules in .hg/histedit-last-edit.txt in case
            # the user needs to ask for help after something
            # surprising happens.
            f = open(repo.join('histedit-last-edit.txt'), 'w')
            f.write(rules)
            f.close()
        else:
#.........这里部分代码省略.........

#.........这里部分代码省略.........
            if srcf or basef or destf:
                raise util.Abort(
                    _('abort and continue do not allow specifying revisions'))
            if opts.get('tool', False):
                ui.warn(_('tool option will be ignored\n'))

            try:
                (originalwd, target, state, skipped, collapsef, keepf,
                 keepbranchesf, external, activebookmark) = restorestatus(repo)
            except error.RepoLookupError:
                if abortf:
                    clearstatus(repo)
                    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 borken state')
                    raise util.Abort(msg, hint=hint)
            if abortf:
                return abort(repo, originalwd, target, state)
        else:
            if srcf and basef:
                raise util.Abort(_('cannot specify both a '
                                   'source and a base'))
            if revf and basef:
                raise util.Abort(_('cannot specify both a '
                                   'revision and a base'))
            if revf and srcf:
                raise util.Abort(_('cannot specify both a '
                                   'revision and a source'))

            cmdutil.checkunfinished(repo)
            cmdutil.bailifchanged(repo)

            if not destf:
                # Destination defaults to the latest revision in the
                # current branch
                branch = repo[None].branch()
                dest = repo[branch]
            else:
                dest = scmutil.revsingle(repo, destf)

            if revf:
                rebaseset = scmutil.revrange(repo, revf)
            elif srcf:
                src = scmutil.revrange(repo, [srcf])
                rebaseset = repo.revs('(%ld)::', src)
            else:
                base = scmutil.revrange(repo, [basef or '.'])
                rebaseset = repo.revs(
                    '(children(ancestor(%ld, %d)) and ::(%ld))::',
                    base, dest, base)
            if rebaseset:
                root = min(rebaseset)
            else:
                root = None

            if not rebaseset:
                repo.ui.debug('base is ancestor of destination\n')
                result = None
            elif (not (keepf or obsolete._enabled)
                  and repo.revs('first(children(%ld) - %ld)',
                                rebaseset, rebaseset)):
                raise util.Abort(
                    _("can't remove original changesets with"

#.........这里部分代码省略.........
                                                  parentctx, oldctx, new,
                                                  opts, newchildren)
            replaced.extend(replaced_)
            created.extend(created_)
            tmpnodes.extend(tmpnodes_)
        elif action not in ('d', 'drop'):
            if new != oldctx.node():
                replaced.append(oldctx.node())
            if new:
                if new != oldctx.node():
                    created.append(new)
                parentctx = repo[new]

    elif opts.get('abort', False):
        if len(parent) != 0:
            raise util.Abort('no arguments allowed with --abort')
        (parentctxnode, created, replaced, tmpnodes,
         existing, rules, keep, tip, ) = readstate(repo)
        ui.debug('restore wc to old tip %s\n' % node.hex(tip))
        hg.clean(repo, tip)
        ui.debug('should strip created nodes %s\n' %
                 ', '.join([node.hex(n)[:12] for n in created]))
        ui.debug('should strip temp nodes %s\n' %
                 ', '.join([node.hex(n)[:12] for n in tmpnodes]))
        for nodes in (created, tmpnodes, ):
            for n in reversed(nodes):
                try:
                    repair.strip(ui, repo, n)
                except error.LookupError:
                    pass
        os.unlink(os.path.join(repo.path, 'histedit-state'))
        return
    else:
        bailifchanged(repo)
        if os.path.exists(os.path.join(repo.path, 'histedit-state')):
            raise util.Abort('history edit already in progress, try '
                             '--continue or --abort')

        tip, empty = repo.dirstate.parents()


        if len(parent) != 1:
            raise util.Abort('requires exactly one parent revision')
        parent = _revsingle(repo, parent[0]).node()

        keep = opts.get('keep', False)
        revs = between(repo, parent, tip, keep)

        ctxs = [repo[r] for r in revs]
        existing = [r.node() for r in ctxs]
        rules = opts.get('commands', '')
        if not rules:
            rules = '\n'.join([makedesc(c) for c in ctxs])
            rules += editcomment % (node.hex(parent)[:12], node.hex(tip)[:12], )
            rules = ui.edit(rules, ui.username())
            # Save edit rules in .hg/histedit-last-edit.txt in case
            # the user needs to ask for help after something
            # surprising happens.
            f = open(repo.join('histedit-last-edit.txt'), 'w')
            f.write(rules)
            f.close()
        else:
            f = open(rules)
            rules = f.read()
            f.close()
        rules = [l for l in (r.strip() for r in rules.splitlines())

def push(repo, dest, force, revs):
    """push revisions starting at a specified head back to Subversion.
    """
    assert not revs, 'designated revisions for push remains unimplemented.'
    if hasattr(cmdutil, 'bail_if_changed'):
        cmdutil.bail_if_changed(repo)
    else:
        # Since 1.9 (d68ddccf276b)
        cmdutil.bailifchanged(repo)
    checkpush = getattr(repo, 'checkpush', None)
    if checkpush:
        checkpush(force, revs)
    ui = repo.ui
    old_encoding = util.swap_out_encoding()
    # TODO: implement --rev/#rev support
    # TODO: do credentials specified in the URL still work?
    svnurl = repo.ui.expandpath(dest.svnurl)
    svn = dest.svn
    meta = repo.svnmeta(svn.uuid, svn.subdir)

    # Strategy:
    # 1. Find all outgoing commits from this head
    if len(repo.parents()) != 1:
        ui.status('Cowardly refusing to push branch merge\n')
        return 0 # results in nonzero exit status, see hg's commands.py
    workingrev = repo.parents()[0]
    ui.status('searching for changes\n')
    hashes = meta.revmap.hashes()
    outgoing = util.outgoing_revisions(repo, hashes, workingrev.node())
    if not (outgoing and len(outgoing)):
        ui.status('no changes found\n')
        return 1 # so we get a sane exit status, see hg's commands.push
    while outgoing:

        # 2. Commit oldest revision that needs to be pushed
        oldest = outgoing.pop(-1)
        old_ctx = repo[oldest]
        old_pars = old_ctx.parents()
        if len(old_pars) != 1:
            ui.status('Found a branch merge, this needs discussion and '
                      'implementation.\n')
            return 0 # results in nonzero exit status, see hg's commands.py
        # We will commit to svn against this node's parent rev. Any file-level
        # conflicts here will result in an error reported by svn.
        base_ctx = old_pars[0]
        base_revision = hashes[base_ctx.node()][0]
        svnbranch = base_ctx.branch()
        # Find most recent svn commit we have on this branch.
        # This node will become the nearest known ancestor of the pushed rev.
        oldtipctx = base_ctx
        old_children = oldtipctx.descendants()
        seen = set(c.node() for c in old_children)
        samebranchchildren = [c for c in old_children if c.branch() == svnbranch
                              and c.node() in hashes]
        if samebranchchildren:
            # The following relies on descendants being sorted by rev.
            oldtipctx = samebranchchildren[-1]
        # All set, so commit now.
        try:
            pushmod.commit(ui, repo, old_ctx, meta, base_revision, svn)
        except pushmod.NoFilesException:
            ui.warn("Could not push revision %s because it had no changes in svn.\n" %
                     old_ctx)
            return 1

        # 3. Fetch revisions from svn
        # TODO: this probably should pass in the source explicitly - rev too?
        r = repo.pull(dest, force=force)
        assert not r or r == 0

        # 4. Find the new head of the target branch
        # We expect to get our own new commit back, but we might also get other
        # commits that happened since our last pull, or even right after our own
        # commit (race).
        for c in oldtipctx.descendants():
            if c.node() not in seen and c.branch() == svnbranch:
                newtipctx = c

        # 5. Rebase all children of the currently-pushing rev to the new head
        heads = repo.heads(old_ctx.node())
        for needs_transplant in heads:
            def extrafn(ctx, extra):
                if ctx.node() == oldest:
                    return
                extra['branch'] = ctx.branch()
            # TODO: can we avoid calling our own rebase wrapper here?
            rebase(hgrebase.rebase, ui, repo, svn=True, svnextrafn=extrafn,
                   svnsourcerev=needs_transplant)
            # Reload the repo after the rebase. Do not reuse contexts across this.
            newtip = newtipctx.node()
            repo = hg.repository(ui, meta.path)
            newtipctx = repo[newtip]
            # Rewrite the node ids in outgoing to their rebased versions.
            rebasemap = dict()
            for child in newtipctx.descendants():
                rebasesrc = child.extra().get('rebase_source')
                if rebasesrc:
                    rebasemap[node.bin(rebasesrc)] = child.node()
            outgoing = [rebasemap.get(n) or n for n in outgoing]
        # TODO: stop constantly creating the SVNMeta instances.
#.........这里部分代码省略.........

def do_backout(ui, repo, rev, handle_change, commit_change, use_mq=False, reverse_order=False, **opts):
    if not opts.get('force'):
        ui.status('checking for uncommitted changes\n')
        cmdutil.bailifchanged(repo)
    backout = not opts.get('apply')
    desc = {'action': 'backout',
            'Actioned': 'Backed out',
            'actioning': 'backing out',
            'name': 'backout'
            }
    if not backout:
        desc = {'action': 'apply',
                'Actioned': 'Reapplied',
                'actioning': 'Reapplying',
                'name': 'patch'
                }

    rev = scmutil.revrange(repo, rev)
    if len(rev) == 0:
        raise util.Abort('at least one revision required')

    csets = [repo[r] for r in rev]
    csets.sort(reverse=reverse_order, key=lambda cset: cset.rev())

    new_opts = opts.copy()

    def bugs_suffix(bugs):
        if len(bugs) == 0:
            return ''
        elif len(bugs) == 1:
            return ' (bug ' + list(bugs)[0] + ')'
        else:
            return ' (' + ', '.join(map(lambda b: 'bug %s' % b, bugs)) + ')'

    def parse_bugs(msg):
        bugs = set()
        m = BUG_RE.search(msg)
        if m:
            bugs.add(m.group(2))
        return bugs

    def apply_change(node, reverse, push_patch=True, name=None):
        p1, p2 = repo.changelog.parents(node)
        if p2 != nullid:
            raise util.Abort('cannot %s a merge changeset' % desc['action'])

        opts = mdiff.defaultopts
        opts.git = True
        rpatch = StringIO.StringIO()
        orig, mod = (node, p1) if reverse else (p1, node)
        for chunk in patch.diff(repo, node1=orig, node2=mod, opts=opts):
            rpatch.write(chunk)
        rpatch.seek(0)

        saved_stdin = None
        try:
            save_fin = ui.fin
            ui.fin = rpatch
        except:
            # Old versions of hg did not use the ui.fin mechanism
            saved_stdin = sys.stdin
            sys.stdin = rpatch

        handle_change(desc, node, qimport=(use_mq and new_opts.get('nopush')))

        if saved_stdin is None:
            ui.fin = save_fin
        else:
            sys.stdin = saved_stdin

    allbugs = set()
    messages = []
    for cset in csets:
        # Hunt down original description if we might want to use it
        orig_desc = None
        orig_desc_cset = None
        orig_author = None
        r = cset
        while len(csets) == 1 or not opts.get('single'):
            ui.debug("Parsing message for %s\n" % short(r.node()))
            m = backout_re.match(r.description())
            if m:
                ui.debug("  looks like a backout of %s\n" % m.group(1))
            else:
                m = reapply_re.match(r.description())
                if m:
                    ui.debug("  looks like a reapply of %s\n" % m.group(1))
                else:
                    ui.debug("  looks like the original description\n")
                    orig_desc = r.description()
                    orig_desc_cset = r
                    orig_author = r.user()
                    break
            r = repo[m.group(1)]

        bugs = parse_bugs(cset.description())
        allbugs.update(bugs)
        node = cset.node()
        shortnode = short(node)
        ui.status('%s %s\n' % (desc['actioning'], shortnode))
#.........这里部分代码省略.........

def histedit(ui, repo, *freeargs, **opts):
    """interactively edit changeset history

    This command edits changesets between ANCESTOR and the parent of
    the working directory.

    With --outgoing, this edits changesets not found in the
    destination repository. If URL of the destination is omitted, the
    'default-push' (or 'default') path will be used.

    For safety, this command is aborted, also if there are ambiguous
    outgoing revisions which may confuse users: for example, there are
    multiple branches containing outgoing revisions.

    Use "min(outgoing() and ::.)" or similar revset specification
    instead of --outgoing to specify edit target revision exactly in
    such ambiguous situation. See :hg:`help revsets` for detail about
    selecting revisions.
    """
    # TODO only abort if we try and histedit mq patches, not just
    # blanket if mq patches are applied somewhere
    mq = getattr(repo, "mq", None)
    if mq and mq.applied:
        raise util.Abort(_("source has mq patches applied"))

    # basic argument incompatibility processing
    outg = opts.get("outgoing")
    cont = opts.get("continue")
    abort = opts.get("abort")
    force = opts.get("force")
    rules = opts.get("commands", "")
    revs = opts.get("rev", [])
    goal = "new"  # This invocation goal, in new, continue, abort
    if force and not outg:
        raise util.Abort(_("--force only allowed with --outgoing"))
    if cont:
        if util.any((outg, abort, revs, freeargs, rules)):
            raise util.Abort(_("no arguments allowed with --continue"))
        goal = "continue"
    elif abort:
        if util.any((outg, revs, freeargs, rules)):
            raise util.Abort(_("no arguments allowed with --abort"))
        goal = "abort"
    else:
        if os.path.exists(os.path.join(repo.path, "histedit-state")):
            raise util.Abort(_("history edit already in progress, try " "--continue or --abort"))
        if outg:
            if revs:
                raise util.Abort(_("no revisions allowed with --outgoing"))
            if len(freeargs) > 1:
                raise util.Abort(_("only one repo argument allowed with --outgoing"))
        else:
            revs.extend(freeargs)
            if len(revs) != 1:
                raise util.Abort(_("histedit requires exactly one ancestor revision"))

    if goal == "continue":
        (parentctxnode, rules, keep, topmost, replacements) = readstate(repo)
        parentctx = repo[parentctxnode]
        parentctx, repl = bootstrapcontinue(ui, repo, parentctx, rules, opts)
        replacements.extend(repl)
    elif goal == "abort":
        (parentctxnode, rules, keep, topmost, replacements) = readstate(repo)
        mapping, tmpnodes, leafs, _ntm = processreplacement(repo, replacements)
        ui.debug("restore wc to old parent %s\n" % node.short(topmost))
        # check whether we should update away
        parentnodes = [c.node() for c in repo[None].parents()]
        for n in leafs | set([parentctxnode]):
            if n in parentnodes:
                hg.clean(repo, topmost)
                break
        else:
            pass
        cleanupnode(ui, repo, "created", tmpnodes)
        cleanupnode(ui, repo, "temp", leafs)
        os.unlink(os.path.join(repo.path, "histedit-state"))
        return
    else:
        cmdutil.checkunfinished(repo)
        cmdutil.bailifchanged(repo)

        topmost, empty = repo.dirstate.parents()
        if outg:
            if freeargs:
                remote = freeargs[0]
            else:
                remote = None
            root = findoutgoing(ui, repo, remote, force, opts)
        else:
            root = revs[0]
            root = scmutil.revsingle(repo, root).node()

        keep = opts.get("keep", False)
        revs = between(repo, root, topmost, keep)
        if not revs:
            raise util.Abort(_("%s is not an ancestor of working directory") % node.short(root))

        ctxs = [repo[r] for r in revs]
        if not rules:
            rules = "\n".join([makedesc(c) for c in ctxs])
#.........这里部分代码省略.........

def do_collapse(ui, repo, first, last, revs, movelog, timedelta, opts):        
    ui.debug(_('Collapsing revisions %s\n') % revs)

    if opts['debugdelay']:
        debug_delay = float(opts['debugdelay'])
    else:
        debug_delay = False

    for r in revs:
        if repo[r].user() != ui.username() and not opts['force']:
            raise util.Abort(_('revision %s does not belong to %s\n') %
                (r, ui.username()))
        if r != last:
            children = repo[r].children()
            if len(children) > 1:
                for c in children:
                    if not c.rev() in revs:
                        raise util.Abort(_('revision %s has child %s not '
                            'being collapsed, please rebase\n') % (r, c.rev()))
        if r != first:
            parents = repo[r].parents()
            if len(parents) > 1:
                for p in parents:
                    if not p.rev() in revs:
                        raise util.Abort(_('revision %s has parent %s not '
                            'being collapsed.') % (r, p.rev()))

    if len(repo[first].parents()) > 1:
        raise util.Abort(_('start revision %s has multiple parents, '
            'won\'t collapse.') % first)

    try:
        cmdutil.bailifchanged(repo)
    except AttributeError:
        cmdutil.bail_if_changed(repo)

    parent = repo[first].parents()[0]
    tomove = list(repo.changelog.descendants(last))

    head_hgtags = get_hgtags_from_heads(ui, repo, last)
    if '.hgtags' in parent:
        parent_hgtags = parent['.hgtags'].data()
    else:
        parent_hgtags = False

    movemap = dict.fromkeys(tomove, nullrev)
    ui.debug(_('will move revisions: %s\n') % tomove)

    tagsmap = dict()
    if opts['noop']:
        ui.status(_('noop: not collapsing\n'))
    else:
        origparent = repo['.'].rev()
        collapsed = None

        try:
            branch = repo[last].branch()
            collapsed = makecollapsed(ui, repo, parent, revs, branch, tagsmap,
                                      parent_hgtags, movelog, opts)
            movemap[max(revs)] = collapsed
            movedescendants(ui, repo, collapsed, tomove, movemap, tagsmap, 
                            parent_hgtags, movelog, debug_delay)
            fix_hgtags(ui, repo, head_hgtags, tagsmap)
        except:
            merge.update(repo, repo[origparent].rev(), False, True, False)
            if collapsed:
                repair.strip(ui, repo, collapsed.node(), "strip")
            raise

        if not opts['keep']:
            ui.debug(_('stripping revision %d\n') % first)
            repair.strip(ui, repo, repo[first].node(), "strip")

        ui.status(_('collapse completed\n'))

def push(repo, dest, force, revs):
    """push revisions starting at a specified head back to Subversion.
    """
    assert not revs, 'designated revisions for push remains unimplemented.'
    cmdutil.bailifchanged(repo)
    checkpush = getattr(repo, 'checkpush', None)
    if checkpush:
        try:
            # The checkpush function changed as of e10000369b47 (first
            # in 3.0) in mercurial
            from mercurial.exchange import pushoperation
            pushop = pushoperation(repo, dest, force, revs, False)
            checkpush(pushop)
        except (ImportError, TypeError):
            checkpush(force, revs)

    ui = repo.ui
    old_encoding = util.swap_out_encoding()

    try:
        hasobsolete = obsolete._enabled
    except:
        hasobsolete = False

    temporary_commits = []
    obsmarkers = []
    try:
        # TODO: implement --rev/#rev support
        # TODO: do credentials specified in the URL still work?
        svn = dest.svn
        meta = repo.svnmeta(svn.uuid, svn.subdir)

        # Strategy:
        # 1. Find all outgoing commits from this head
        if len(repo[None].parents()) != 1:
            ui.status('Cowardly refusing to push branch merge\n')
            return 0 # results in nonzero exit status, see hg's commands.py
        workingrev = repo[None].parents()[0]
        workingbranch = workingrev.branch()
        ui.status('searching for changes\n')
        hashes = meta.revmap.hashes()
        outgoing = util.outgoing_revisions(repo, hashes, workingrev.node())
        if not (outgoing and len(outgoing)):
            ui.status('no changes found\n')
            return 1 # so we get a sane exit status, see hg's commands.push

        tip_ctx = repo[outgoing[-1]].p1()
        svnbranch = tip_ctx.branch()
        modified_files = {}
        for i in range(len(outgoing) - 1, -1, -1):
            # 2. Pick the oldest changeset that needs to be pushed
            current_ctx = repo[outgoing[i]]
            original_ctx = current_ctx

            if len(current_ctx.parents()) != 1:
                ui.status('Found a branch merge, this needs discussion and '
                          'implementation.\n')
                # results in nonzero exit status, see hg's commands.py
                return 0

            # 3. Move the changeset to the tip of the branch if necessary
            conflicts = False
            for file in current_ctx.files():
                if file in modified_files:
                    conflicts = True
                    break

            if conflicts or current_ctx.branch() != svnbranch:
                util.swap_out_encoding(old_encoding)
                try:
                    def extrafn(ctx, extra):
                        extra['branch'] = ctx.branch()

                    ui.note('rebasing %s onto %s \n' % (current_ctx, tip_ctx))
                    hgrebase.rebase(ui, repo,