# bruterebase.py - brute force rebase testing

#

# Copyright 2017 Facebook, Inc.

#

# This software may be used and distributed according to the terms of the

# GNU General Public License version 2 or any later version.

from __future__ import absolute_import

from mercurial import (

    error,

    registrar,

    revsetlang,

)

from hgext import rebase

try:

    xrange

except NameError:

    xrange = range

cmdtable = {}

command = registrar.command(cmdtable)

@command(b'debugbruterebase')

def debugbruterebase(ui, repo, source, dest):

    """for every non-empty subset of source, run rebase -r subset -d dest

    Print one line summary for each subset. Assume obsstore is enabled.

    """

    srevs = list(repo.revs(source))

    with repo.wlock(), repo.lock():

        repolen = len(repo)

        cl = repo.changelog

        def getdesc(rev):

            result = cl.changelogrevision(rev).description

            if rev >= repolen:

                result += b"'"

            return result

        for i in xrange(1, 2 ** len(srevs)):

            subset = [rev for j, rev in enumerate(srevs) if i & (1 << j) != 0]

            spec = revsetlang.formatspec(b'%ld', subset)

            tr = repo.transaction(b'rebase')

            tr.report = lambda x: 0 # hide "transaction abort"

            ui.pushbuffer()

            try:

                rebase.rebase(ui, repo, dest=dest, rev=[spec])

            except error.Abort as ex:

                summary = b'ABORT: %s' % ex

            except Exception as ex:

                summary = b'CRASH: %s' % ex

            else:

                # short summary about new nodes

                cl = repo.changelog

                descs = []

                for rev in xrange(repolen, len(repo)):

                    desc = b'%s:' % getdesc(rev)

                    for prev in cl.parentrevs(rev):

                        if prev > -1:

                            desc += getdesc(prev)

                    descs.append(desc)

                descs.sort()

                summary = ' '.join(descs)

            ui.popbuffer()

            repo.vfs.tryunlink(b'rebasestate')

            subsetdesc = b''.join(getdesc(rev) for rev in subset)

            ui.write((b'%s: %s\n') % (subsetdesc.rjust(len(srevs)), summary))

            tr.abort()