view hgext3rd/topic/discovery.py @ 2712:f19b314d8475

topics: add t0 and b0 to the stack

t0 or b0 will be the base of the stack and it's the parent of t1 or b1. The cool
thing about this is that if you update to t0 using `hg up t0` or do `hg prev` on
t1, you will be updated to t0 with the current topic preserved.

This patch adds t0 to stack and implement the preserving topic case for t0 while
using `hg update`.

from __future__ import absolute_import

import weakref

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

def _headssummary(orig, *args):
    # In mercurial < 4.2, we receive repo, remote and outgoing as arguments
    if len(args) == 3:
        pushoparg = False
        repo, remote, outgoing = args

    # In mercurial > 4.3, we receive the pushop as arguments
    elif len(args) == 1:
        pushoparg = True
        pushop = args[0]
        repo = pushop.repo.unfiltered()
        remote = pushop.remote
    else:
        msg = 'topic-ext _headssummary() takes 1 or 3 arguments (%d given)'
        raise TypeError(msg % len(args))

    publishing = ('phases' not in remote.listkeys('namespaces')
                  or bool(remote.listkeys('phases').get('publishing', False)))
    if publishing or not remote.capable('topics'):
        return orig(*args)

    class repocls(repo.__class__):
        # awful hack to see branch as "branch:topic"
        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

        def revbranchcache(self):
            rbc = super(repocls, self).revbranchcache()
            changelog = self.changelog

            def branchinfo(rev):
                branch, close = changelog.branchinfo(rev)
                topic = repo[rev].topic()
                if topic:
                    branch = "%s:%s" % (branch, topic)
                return branch, close

            rbc.branchinfo = branchinfo
            return rbc

    oldrepocls = repo.__class__
    try:
        repo.__class__ = repocls
        unxx = repo.filtered('unfiltered-topic')
        repo.unfiltered = lambda: unxx
        if pushoparg:
            pushop.repo = repo
            summary = orig(pushop)
        else:
            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][0]], ) + value[1:]
        return summary
    finally:
        if 'unfiltered' in vars(repo):
            del repo.unfiltered
        repo.__class__ = oldrepocls

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):
    """This is used to check for new heads when publishing changeset"""
    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):
    checktypes = ('check:heads', 'check:updated-heads')
    hascheck = any(p.type in checktypes for p in bundler._parts)
    if not hascheck and pushop.outdatedphases:
        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)
    # we need a proper wrap b2 part stuff
    extensions.wrapfunction(bundle2, 'handlecheckheads', handlecheckheads)
    bundle2.handlecheckheads.params = frozenset()
    bundle2.parthandlermapping['check:heads'] = bundle2.handlecheckheads
    if util.safehasattr(bundle2, 'handlecheckupdatedheads'):
        # we still need a proper wrap b2 part stuff
        extensions.wrapfunction(bundle2, 'handlecheckupdatedheads', handlecheckheads)
        bundle2.handlecheckupdatedheads.params = frozenset()
        bundle2.parthandlermapping['check:updated-heads'] = bundle2.handlecheckupdatedheads
    extensions.wrapfunction(exchange, '_pushb2phases', _pushb2phases)
    exchange.b2partsgenmapping['phase'] = exchange._pushb2phases