annotate hgext/rebase.py @ 7012:78341ea65d16

restructure helptable

When looking up a help topic, the key is now only matched against the
short names for each topic, and not the header. So

  hg help 'Environment Variables'

must be replaced with

  hg help env

# rebase.py - rebasing feature for mercurial
#
# Copyright 2008 Stefano Tortarolo <stefano.tortarolo at gmail dot com>
#
# This software may be used and distributed according to the terms
# of the GNU General Public License, incorporated herein by reference.

''' Rebasing feature

This extension lets you rebase changesets in an existing Mercurial repository.

For more information:
http://www.selenic.com/mercurial/wiki/index.cgi/RebaseProject
'''

from mercurial import util, repair, merge, cmdutil, dispatch, commands
from mercurial.commands import templateopts
from mercurial.node import nullrev
from mercurial.i18n import _
import os, errno

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
    onto another. This can be useful for linearizing local changes relative to
    a master development tree.

    If a rebase is interrupted to manually resolve a merge, it can be continued
    with --continue or aborted with --abort.
    """
    originalwd = target = source = None
    external = nullrev
    state = skipped = {}

    lock = wlock = None
    try:
        lock = repo.lock()
        wlock = repo.wlock()

        # Validate input and define rebasing points
        destf = opts.get('dest', None)
        srcf = opts.get('source', None)
        basef = opts.get('base', None)
        contf = opts.get('continue')
        abortf = opts.get('abort')
        collapsef = opts.get('collapse', False)
        if contf or abortf:
            if contf and abortf:
                raise dispatch.ParseError('rebase',
                                    _('cannot use both abort and continue'))
            if collapsef:
                raise dispatch.ParseError('rebase',
                        _('cannot use collapse with continue or abort'))

            if (srcf or basef or destf):
                raise dispatch.ParseError('rebase',
                    _('abort and continue do not allow specifying revisions'))

            originalwd, target, state, collapsef, external = restorestatus(repo)
            if abortf:
                abort(repo, originalwd, target, state)
                return
        else:
            if srcf and basef:
                raise dispatch.ParseError('rebase', _('cannot specify both a '
                                                        'revision and a base'))
            cmdutil.bail_if_changed(repo)
            result = buildstate(repo, destf, srcf, basef, collapsef)
            if result:
                originalwd, target, state, external = result
            else: # Empty state built, nothing to rebase
                repo.ui.status(_('nothing to rebase\n'))
                return

        # Rebase
        targetancestors = list(repo.changelog.ancestors(target))
        targetancestors.append(target)

        for rev in util.sort(state):
            if state[rev] == -1:
                storestatus(repo, originalwd, target, state, collapsef,
                                                                external)
                rebasenode(repo, rev, target, state, skipped, targetancestors,
                                                                collapsef)
        ui.note(_('rebase merging completed\n'))

        if collapsef:
            p1, p2 = defineparents(repo, min(state), target,
                                                        state, targetancestors)
            concludenode(repo, rev, p1, external, state, collapsef,
                                                last=True, skipped=skipped)

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

        if not opts.get('keep'):
            # Remove no more useful revisions
            if (util.set(repo.changelog.descendants(min(state)))
                                                    - util.set(state.keys())):
                ui.warn(_("warning: new changesets detected on source branch, "
                                                        "not stripping\n"))
            else:
                repair.strip(repo.ui, repo, repo[min(state)].node(), "strip")

        clearstatus(repo)
        ui.status(_("rebase completed\n"))
        if skipped:
            ui.note(_("%d revisions have been skipped\n") % len(skipped))
    finally:
        del lock, wlock

def concludenode(repo, rev, p1, p2, state, collapse, last=False, skipped={}):
    """Skip commit if collapsing has been required and rev is not the last
    revision, commit otherwise
    """
    repo.dirstate.setparents(repo[p1].node(), repo[p2].node())

    if collapse and not last:
        return None

    # Commit, record the old nodeid
    m, a, r = repo.status()[:3]
    newrev = nullrev
    try:
        if last:
            commitmsg = 'Collapsed revision'
            for rebased in state:
                if rebased not in skipped:
                    commitmsg += '\n* %s' % repo[rebased].description()
            commitmsg = repo.ui.edit(commitmsg, repo.ui.username())
        else:
            commitmsg = repo[rev].description()
        # Commit might fail if unresolved files exist
        newrev = repo.commit(m+a+r,
                            text=commitmsg,
                            user=repo[rev].user(),
                            date=repo[rev].date(),
                            extra={'rebase_source': repo[rev].hex()})
        return newrev
    except util.Abort:
        # Invalidate the previous setparents
        repo.dirstate.invalidate()
        raise

def rebasenode(repo, rev, target, state, skipped, targetancestors, collapse):
    'Rebase a single revision'
    repo.ui.debug(_("rebasing %d:%s\n") % (rev, repo[rev].node()))

    p1, p2 = defineparents(repo, rev, target, state, targetancestors)

    # Merge phase
    if len(repo.parents()) != 2:
        # Update to target and merge it with local
        merge.update(repo, p1, False, True, False)
        repo.dirstate.write()
        stats = merge.update(repo, rev, True, False, False)

        if stats[3] > 0:
            raise util.Abort(_('fix unresolved conflicts with hg resolve then '
                                                'run hg rebase --continue'))
    else: # we have an interrupted rebase
        repo.ui.debug(_('resuming interrupted rebase\n'))


    newrev = concludenode(repo, rev, p1, p2, state, collapse)

    # Update the state
    if newrev is not None:
        state[rev] = repo[newrev].rev()
    else:
        if not collapse:
            repo.ui.note(_('no changes, revision %d skipped\n') % rev)
            repo.ui.debug(_('next revision set to %s\n') % p1)
            skipped[rev] = True
        state[rev] = p1

def defineparents(repo, rev, target, state, targetancestors):
    'Return the new parent relationship of the revision that will be rebased'
    parents = repo[rev].parents()
    p1 = p2 = nullrev

    P1n = parents[0].rev()
    if P1n in targetancestors:
        p1 = target
    elif P1n in state:
        p1 = state[P1n]
    else: # P1n external
        p1 = target
        p2 = P1n

    if len(parents) == 2 and parents[1].rev() not in targetancestors:
        P2n = parents[1].rev()
        # interesting second parent
        if P2n in state:
            if p1 == target: # P1n in targetancestors or external
                p1 = state[P2n]
            else:
                p2 = state[P2n]
        else: # P2n external
            if p2 != nullrev: # P1n external too => rev is a merged revision
                raise util.Abort(_('cannot use revision %d as base, result '
                        'would have 3 parents') % rev)
            p2 = P2n
    return p1, p2

def updatemq(repo, state, skipped, **opts):
    'Update rebased mq patches - finalize and then import them'
    mqrebase = {}
    for p in repo.mq.applied:
        if repo[p.rev].rev() in state:
            repo.ui.debug(_('revision %d is an mq patch (%s), finalize it.\n') %
                                        (repo[p.rev].rev(), p.name))
            mqrebase[repo[p.rev].rev()] = p.name

    if mqrebase:
        repo.mq.finish(repo, mqrebase.keys())

        # We must start import from the newest revision
        mq = mqrebase.keys()
        mq.sort()
        mq.reverse()
        for rev in mq:
            if rev not in skipped:
                repo.ui.debug(_('import mq patch %d (%s)\n')
                              % (state[rev], mqrebase[rev]))
                repo.mq.qimport(repo, (), patchname=mqrebase[rev],
                            git=opts.get('git', False),rev=[str(state[rev])])
        repo.mq.save_dirty()

def storestatus(repo, originalwd, target, state, collapse, external):
    'Store the current status to allow recovery'
    f = repo.opener("rebasestate", "w")
    f.write(repo[originalwd].hex() + '\n')
    f.write(repo[target].hex() + '\n')
    f.write(repo[external].hex() + '\n')
    f.write('%d\n' % int(collapse))
    for d, v in state.items():
        oldrev = repo[d].hex()
        newrev = repo[v].hex()
        f.write("%s:%s\n" % (oldrev, newrev))
    f.close()
    repo.ui.debug(_('rebase status stored\n'))

def clearstatus(repo):
    'Remove the status files'
    if os.path.exists(repo.join("rebasestate")):
        util.unlink(repo.join("rebasestate"))

def restorestatus(repo):
    'Restore a previously stored status'
    try:
        target = None
        collapse = False
        external = nullrev
        state = {}
        f = repo.opener("rebasestate")
        for i, l in enumerate(f.read().splitlines()):
            if i == 0:
                originalwd = repo[l].rev()
            elif i == 1:
                target = repo[l].rev()
            elif i == 2:
                external = repo[l].rev()
            elif i == 3:
                collapse = bool(int(l))
            else:
                oldrev, newrev = l.split(':')
                state[repo[oldrev].rev()] = repo[newrev].rev()
        repo.ui.debug(_('rebase status resumed\n'))
        return originalwd, target, state, collapse, external
    except IOError, err:
        if err.errno != errno.ENOENT:
            raise
        raise util.Abort(_('no rebase in progress'))

def abort(repo, originalwd, target, state):
    'Restore the repository to its original state'
    if util.set(repo.changelog.descendants(target)) - util.set(state.values()):
        repo.ui.warn(_("warning: new changesets detected on target branch, "
                                                    "not stripping\n"))
    else:
        # Strip from the first rebased revision
        merge.update(repo, repo[originalwd].rev(), False, True, False)
        rebased = filter(lambda x: x > -1, state.values())
        if rebased:
            strippoint = min(rebased)
            repair.strip(repo.ui, repo, repo[strippoint].node(), "strip")
        clearstatus(repo)
        repo.ui.status(_('rebase aborted\n'))

def buildstate(repo, dest, src, base, collapse):
    'Define which revisions are going to be rebased and where'
    state = {}
    targetancestors = util.set()

    if not dest:
         # Destination defaults to the latest revision in the current branch
        branch = repo[None].branch()
        dest = repo[branch].rev()
    else:
        if 'qtip' in repo.tags() and (repo[dest].hex() in
                                [s.rev for s in repo.mq.applied]):
            raise util.Abort(_('cannot rebase onto an applied mq patch'))
        dest = repo[dest].rev()

    if src:
        commonbase = repo[src].ancestor(repo[dest])
        if commonbase == repo[src]:
            raise util.Abort(_('cannot rebase an ancestor'))
        if commonbase == repo[dest]:
            raise util.Abort(_('cannot rebase a descendant'))
        source = repo[src].rev()
    else:
        if base:
            cwd = repo[base].rev()
        else:
            cwd = repo['.'].rev()

        if cwd == dest:
            repo.ui.debug(_('already working on current\n'))
            return None

        targetancestors = util.set(repo.changelog.ancestors(dest))
        if cwd in targetancestors:
            repo.ui.debug(_('already working on the current branch\n'))
            return None

        cwdancestors = util.set(repo.changelog.ancestors(cwd))
        cwdancestors.add(cwd)
        rebasingbranch = cwdancestors - targetancestors
        source = min(rebasingbranch)

    repo.ui.debug(_('rebase onto %d starting from %d\n') % (dest, source))
    state = dict.fromkeys(repo.changelog.descendants(source), nullrev)
    external = nullrev
    if collapse:
        if not targetancestors:
            targetancestors = util.set(repo.changelog.ancestors(dest))
        for rev in state:
            # Check externals and fail if there are more than one
            for p in repo[rev].parents():
                if (p.rev() not in state and p.rev() != source
                            and p.rev() not in targetancestors):
                    if external != nullrev:
                        raise util.Abort(_('unable to collapse, there is more '
                                'than one external parent'))
                    external = p.rev()

    state[source] = nullrev
    return repo['.'].rev(), repo[dest].rev(), state, external

def pulldelegate(pullfunction, repo, *args, **opts):
    'Call rebase after pull if the latter has been invoked with --rebase'
    if opts.get('rebase'):
        if opts.get('update'):
            raise util.Abort(_('--update and --rebase are not compatible'))

        cmdutil.bail_if_changed(repo)
        revsprepull = len(repo)
        pullfunction(repo.ui, repo, *args, **opts)
        revspostpull = len(repo)
        if revspostpull > revsprepull:
            rebase(repo.ui, repo, **opts)
    else:
        pullfunction(repo.ui, repo, *args, **opts)

def uisetup(ui):
    'Replace pull with a decorator to provide --rebase option'
    # cribbed from color.py
    aliases, entry = cmdutil.findcmd(ui, 'pull', commands.table)
    for candidatekey, candidateentry in commands.table.iteritems():
        if candidateentry is entry:
            cmdkey, cmdentry = candidatekey, entry
            break

    decorator = lambda ui, repo, *args, **opts: \
                    pulldelegate(cmdentry[0], repo, *args, **opts)
    # make sure 'hg help cmd' still works
    decorator.__doc__ = cmdentry[0].__doc__
    decoratorentry = (decorator,) + cmdentry[1:]
    rebaseopt = ('', 'rebase', None,
                            _("rebase working directory to branch head"))
    decoratorentry[1].append(rebaseopt)
    commands.table[cmdkey] = decoratorentry

cmdtable = {
"rebase":
        (rebase,
        [
        ('', 'keep', False, _('keep original revisions')),
        ('s', 'source', '', _('rebase from a given revision')),
        ('b', 'base', '', _('rebase from the base of a given revision')),
        ('d', 'dest', '', _('rebase onto a given revision')),
        ('', 'collapse', False, _('collapse the rebased revisions')),
        ('c', 'continue', False, _('continue an interrupted rebase')),
        ('a', 'abort', False, _('abort an interrupted rebase')),] +
         templateopts,
        _('hg rebase [-s rev | -b rev] [-d rev] [--collapse] | [-c] | [-a] | '
                                                                '[--keep]')),
}