annotate hgext3rd/topic/destination.py @ 6935:954d7ea5cd67 stable tip

stack: when stack base is obsolete, pick any successor, even if at random

There are situations when s0 is obsolete and we also cannot pick just one
successor for it to use in stack. In such a case, let's pick the "latest"
successor from the first set.

We're assuming that obsutil.successorssets() returns data in the same order (it
should, since it makes sure to sort data internally). Keeping that in mind,
while the successor picked for s0 by this code is not based on any sort of
sophisticated logic, it should nonetheless be the same every time.

This patch is probably not going to completely break anything that was
previously working fine, because the previous behavior was to just abort with
an exception.

from __future__ import absolute_import

from mercurial.i18n import _
from mercurial import (
    bookmarks,
    destutil,
    error,
    extensions,
)
from . import (
    common,
    topicmap,
)
from .evolvebits import builddependencies

def _destmergebranch(orig, repo, action=b'merge', sourceset=None,
                     onheadcheck=True, destspace=None):
    # XXX: take destspace into account
    if sourceset is None:
        p1 = repo[b'.']
    else:
        # XXX: using only the max here is flacky. That code should eventually
        # be updated to take care of the whole sourceset.
        p1 = repo[max(sourceset)]
    top = None
    if common.hastopicext(repo):
        top = p1.topic()
    if top:
        revs = repo.revs(b'topic(%s) - obsolete()', top)
        deps, rdeps = builddependencies(repo, revs)
        heads = [r for r in revs if not rdeps[r]]
        if onheadcheck and p1.rev() not in heads:
            raise error.Abort(_(b"not at topic head, update or explicit"))

        # prune heads above the source
        otherheads = set(heads)
        pool = set([p1.rev()])
        while pool:
            current = pool.pop()
            otherheads.discard(current)
            pool.update(rdeps[current])
        if not otherheads:
            # nothing to do at the topic level
            bhead = ngtip(repo, p1.branch(), all=True)
            if not bhead:
                raise error.NoMergeDestAbort(_(b"nothing to merge"))
            elif 1 == len(bhead):
                return bhead[0]
            else:
                msg = _(b"branch '%s' has %d heads "
                        b"- please merge with an explicit rev")
                hint = _(b"run 'hg heads .' to see heads")
                raise error.ManyMergeDestAbort(msg % (p1.branch(), len(bhead)),
                                               hint=hint)
        elif len(otherheads) == 1:
            return otherheads.pop()
        else:
            msg = _(b"topic '%s' has %d heads "
                    b"- please merge with an explicit rev") % (top, len(heads))
            raise error.ManyMergeDestAbort(msg)
    return orig(repo, action, sourceset, onheadcheck, destspace=destspace)

def _destupdatetopic(repo, clean, check=None):
    """decide on an update destination from current topic"""
    if not common.hastopicext(repo):
        return None, None, None
    movemark = node = None
    topic = repo.currenttopic
    if topic:
        revs = repo.revs(b'.::topic(%s)', topic)
    elif repo[b'.'].topic():
        revs = []
    else:
        return None, None, None
    if revs:
        node = revs.last()
    else:
        node = repo[b'.'].node()
    if bookmarks.isactivewdirparent(repo):
        movemark = repo[b'.'].node()
    return node, movemark, None

def desthistedit(orig, ui, repo):
    if not common.hastopicext(repo):
        return None
    if not (ui.config(b'histedit', b'defaultrev', None) is None
            and repo.currenttopic):
        return orig(ui, repo)
    revs = repo.revs(b'::. and stack()')
    if revs:
        return revs.min()
    return None

def ngtip(repo, branch, all=False):
    """tip new generation"""
    ## search for untopiced heads of branch
    # could be heads((::branch(x) - topic()))
    # but that is expensive
    #
    # we should write plain code instead

    tmap = topicmap.gettopicrepo(repo).branchmap()
    if branch not in tmap:
        return []
    elif all:
        return tmap.branchheads(branch)
    else:
        return [tmap.branchtip(branch)]

def modsetup(ui):
    """run a uisetup time to install all destinations wrapping"""
    extensions.wrapfunction(destutil, '_destmergebranch', _destmergebranch)
    bridx = destutil.destupdatesteps.index(b'branch')
    destutil.destupdatesteps.insert(bridx, b'topic')
    destutil.destupdatestepmap[b'topic'] = _destupdatetopic
    extensions.wrapfunction(destutil, 'desthistedit', desthistedit)