view hgext3rd/topic/discovery.py @ 2257:7980ca5b1217

checkheads: add a small debug message in case were we give up fast

When node is unknown we assume it will stay. Yet, we might have markers to it
that are going to be pushed. However, we do not have branch (ancestors)
information unless we are very lucky an all of them are pruned. So for now we do
not do anything assuming this will be rare.

We still add a small debug message to help detecting such situation in the
future.

from __future__ import absolute_import

import weakref

from mercurial.i18n import _
from mercurial import (
    branchmap,
    bundle2,
    discovery,
    error,
    exchange,
    extensions,
    wireproto,
)

from . import topicmap

def _headssummary(orig, repo, remote, outgoing):
    publishing = ('phases' not in remote.listkeys('namespaces')
                  or bool(remote.listkeys('phases').get('publishing', False)))
    if publishing or not remote.capable('topics'):
        return orig(repo, remote, outgoing)
    oldrepo = repo.__class__
    oldbranchcache = branchmap.branchcache
    oldfilename = branchmap._filename
    try:
        class repocls(repo.__class__):
            def __getitem__(self, key):
                ctx = super(repocls, self).__getitem__(key)
                oldbranch = ctx.branch

                def branch():
                    branch = oldbranch()
                    topic = ctx.topic()
                    if topic:
                        branch = "%s:%s" % (branch, topic)
                    return branch

                ctx.branch = branch
                return ctx

        repo.__class__ = repocls
        branchmap.branchcache = topicmap.topiccache
        branchmap._filename = topicmap._filename
        summary = orig(repo, remote, outgoing)
        for key, value in summary.iteritems():
            if ':' in key: # This is a topic
                if value[0] is None and value[1]:
                    summary[key] = ([value[1].pop(0)], ) + value[1:]
        return summary
    finally:
        repo.__class__ = oldrepo
        branchmap.branchcache = oldbranchcache
        branchmap._filename = oldfilename

def wireprotobranchmap(orig, repo, proto):
    oldrepo = repo.__class__
    try:
        class repocls(repo.__class__):
            def branchmap(self):
                usetopic = not self.publishing()
                return super(repocls, self).branchmap(topic=usetopic)
        repo.__class__ = repocls
        return orig(repo, proto)
    finally:
        repo.__class__ = oldrepo


# Discovery have deficiency around phases, branch can get new heads with pure
# phases change. This happened with a changeset was allowed to be pushed
# because it had a topic, but it later become public and create a new branch
# head.
#
# Handle this by doing an extra check for new head creation server side
def _nbheads(repo):
    data = {}
    for b in repo.branchmap().iterbranches():
        if ':' in b[0]:
            continue
        data[b[0]] = len(b[1])
    return data

def handlecheckheads(orig, op, inpart):
    orig(op, inpart)
    if op.repo.publishing():
        return
    tr = op.gettransaction()
    if tr.hookargs['source'] not in ('push', 'serve'): # not a push
        return
    tr._prepushheads = _nbheads(op.repo)
    reporef = weakref.ref(op.repo)
    oldvalidator = tr.validator

    def validator(tr):
        repo = reporef()
        if repo is not None:
            repo.invalidatecaches()
            finalheads = _nbheads(repo)
            for branch, oldnb in tr._prepushheads.iteritems():
                newnb = finalheads.pop(branch, 0)
                if oldnb < newnb:
                    msg = _('push create a new head on branch "%s"' % branch)
                    raise error.Abort(msg)
            for branch, newnb in finalheads.iteritems():
                if 1 < newnb:
                    msg = _('push create more than 1 head on new branch "%s"'
                            % branch)
                    raise error.Abort(msg)
        return oldvalidator(tr)
    tr.validator = validator
handlecheckheads.params = frozenset()

def _pushb2phases(orig, pushop, bundler):
    hascheck = any(p.type == 'check:heads' for p in bundler._parts)
    if pushop.outdatedphases and not hascheck:
        exchange._pushb2ctxcheckheads(pushop, bundler)
    return orig(pushop, bundler)

def wireprotocaps(orig, repo, proto):
    caps = orig(repo, proto)
    if repo.peer().capable('topics'):
        caps.append('topics')
    return caps

def modsetup(ui):
    """run at uisetup time to install all destinations wrapping"""
    extensions.wrapfunction(discovery, '_headssummary', _headssummary)
    extensions.wrapfunction(wireproto, 'branchmap', wireprotobranchmap)
    extensions.wrapfunction(wireproto, '_capabilities', wireprotocaps)
    extensions.wrapfunction(bundle2, 'handlecheckheads', handlecheckheads)
    # we need a proper wrap b2 part stuff
    bundle2.handlecheckheads.params = frozenset()
    bundle2.parthandlermapping['check:heads'] = bundle2.handlecheckheads
    extensions.wrapfunction(exchange, '_pushb2phases', _pushb2phases)
    exchange.b2partsgenmapping['phase'] = exchange._pushb2phases