hgext/narrow/narrowwirepeer.py

commit: tell user what to do with .hg/last-message.txt

I have always assumed that the message will be reused by the next `hg
commit`, but it seems it's just silently dropped on the next
commit. Let's try to be more helpful by telling the user that they
have to manually tell hg to reuse it.

The file will still be lost if the user runs some other operation in
between (like a non-in-memory rebase). That will be fixed once we've
switched all operations to be in-memory :)

I didn't include `$(hg root)/` in the path in the message to the user
because that would have made the message too long. Hopefully the user
will figure that part out themselves.

Differential Revision: https://phab.mercurial-scm.org/D8463

# narrowwirepeer.py - passes narrow spec with unbundle command
#
# Copyright 2017 Google, 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 (
    bundle2,
    error,
    extensions,
    hg,
    narrowspec,
    pycompat,
    wireprototypes,
    wireprotov1peer,
    wireprotov1server,
)

from . import narrowbundle2


def uisetup():
    wireprotov1peer.wirepeer.narrow_widen = peernarrowwiden


def reposetup(repo):
    def wirereposetup(ui, peer):
        def wrapped(orig, cmd, *args, **kwargs):
            if cmd == b'unbundle':
                # TODO: don't blindly add include/exclude wireproto
                # arguments to unbundle.
                include, exclude = repo.narrowpats
                kwargs["includepats"] = b','.join(include)
                kwargs["excludepats"] = b','.join(exclude)
            return orig(cmd, *args, **kwargs)

        extensions.wrapfunction(peer, b'_calltwowaystream', wrapped)

    hg.wirepeersetupfuncs.append(wirereposetup)


@wireprotov1server.wireprotocommand(
    b'narrow_widen',
    b'oldincludes oldexcludes'
    b' newincludes newexcludes'
    b' commonheads cgversion'
    b' known ellipses',
    permission=b'pull',
)
def narrow_widen(
    repo,
    proto,
    oldincludes,
    oldexcludes,
    newincludes,
    newexcludes,
    commonheads,
    cgversion,
    known,
    ellipses,
):
    """wireprotocol command to send data when a narrow clone is widen. We will
    be sending a changegroup here.

    The current set of arguments which are required:
    oldincludes: the old includes of the narrow copy
    oldexcludes: the old excludes of the narrow copy
    newincludes: the new includes of the narrow copy
    newexcludes: the new excludes of the narrow copy
    commonheads: list of heads which are common between the server and client
    cgversion(maybe): the changegroup version to produce
    known: list of nodes which are known on the client (used in ellipses cases)
    ellipses: whether to send ellipses data or not
    """

    preferuncompressed = False
    try:

        def splitpaths(data):
            # work around ''.split(',') => ['']
            return data.split(b',') if data else []

        oldincludes = splitpaths(oldincludes)
        newincludes = splitpaths(newincludes)
        oldexcludes = splitpaths(oldexcludes)
        newexcludes = splitpaths(newexcludes)
        # validate the patterns
        narrowspec.validatepatterns(set(oldincludes))
        narrowspec.validatepatterns(set(newincludes))
        narrowspec.validatepatterns(set(oldexcludes))
        narrowspec.validatepatterns(set(newexcludes))

        common = wireprototypes.decodelist(commonheads)
        known = wireprototypes.decodelist(known)
        if ellipses == b'0':
            ellipses = False
        else:
            ellipses = bool(ellipses)
        cgversion = cgversion

        bundler = bundle2.bundle20(repo.ui)
        newmatch = narrowspec.match(
            repo.root, include=newincludes, exclude=newexcludes
        )
        oldmatch = narrowspec.match(
            repo.root, include=oldincludes, exclude=oldexcludes
        )
        if not ellipses:
            bundle2.widen_bundle(
                bundler,
                repo,
                oldmatch,
                newmatch,
                common,
                known,
                cgversion,
                ellipses,
            )
        else:
            narrowbundle2.generate_ellipses_bundle2_for_widening(
                bundler, repo, oldmatch, newmatch, cgversion, common, known,
            )
    except error.Abort as exc:
        bundler = bundle2.bundle20(repo.ui)
        manargs = [(b'message', pycompat.bytestr(exc))]
        advargs = []
        if exc.hint is not None:
            advargs.append((b'hint', exc.hint))
        bundler.addpart(bundle2.bundlepart(b'error:abort', manargs, advargs))
        preferuncompressed = True

    chunks = bundler.getchunks()
    return wireprototypes.streamres(
        gen=chunks, prefer_uncompressed=preferuncompressed
    )


def peernarrowwiden(remote, **kwargs):
    for ch in ('commonheads', 'known'):
        kwargs[ch] = wireprototypes.encodelist(kwargs[ch])

    for ch in ('oldincludes', 'newincludes', 'oldexcludes', 'newexcludes'):
        kwargs[ch] = b','.join(kwargs[ch])

    kwargs['ellipses'] = b'%i' % bool(kwargs['ellipses'])
    f = remote._callcompressable(b'narrow_widen', **kwargs)
    return bundle2.getunbundler(remote.ui, f)