view tests/test-wireproto.py @ 44667:b561f3a68e41 stable

discovery: avoid wrongly saying there are nothing to pull

We can get in a situation where a revision passed through `hg pull --rev REV`
are available on the server, but not a descendant of the advertised server
heads.

For example the server could lying be during heads advertisement, to hide some
pull request. Or obsolete/hidden content could be explicitly pulled.

So in this case the lookup associated to `REV` returned successfully, but the
normal discovery will find all advertised heads already known locally. This flip
a special boolean `anyinc` that will prevent any fetch attempt, preventing `REV`
to be pulled over.

We add three line of code to detect this case and make sure a pull actually
happens.

My main target is to make some third party extensions happy (I expect the
associated test to move upstream with the extension). However this fix already
make some of the `infinitepush` test happier.

from __future__ import absolute_import, print_function

import sys

from mercurial import (
    error,
    pycompat,
    ui as uimod,
    util,
    wireprototypes,
    wireprotov1peer,
    wireprotov1server,
)
from mercurial.utils import stringutil

stringio = util.stringio


class proto(object):
    def __init__(self, args):
        self.args = args
        self.name = 'dummyproto'

    def getargs(self, spec):
        args = self.args
        args.setdefault(b'*', {})
        names = spec.split()
        return [args[n] for n in names]

    def checkperm(self, perm):
        pass


wireprototypes.TRANSPORTS['dummyproto'] = {
    'transport': 'dummy',
    'version': 1,
}


class clientpeer(wireprotov1peer.wirepeer):
    def __init__(self, serverrepo, ui):
        self.serverrepo = serverrepo
        self.ui = ui

    def url(self):
        return b'test'

    def local(self):
        return None

    def peer(self):
        return self

    def canpush(self):
        return True

    def close(self):
        pass

    def capabilities(self):
        return [b'batch']

    def _call(self, cmd, **args):
        args = pycompat.byteskwargs(args)
        res = wireprotov1server.dispatch(self.serverrepo, proto(args), cmd)
        if isinstance(res, wireprototypes.bytesresponse):
            return res.data
        elif isinstance(res, bytes):
            return res
        else:
            raise error.Abort('dummy client does not support response type')

    def _callstream(self, cmd, **args):
        return stringio(self._call(cmd, **args))

    @wireprotov1peer.batchable
    def greet(self, name):
        f = wireprotov1peer.future()
        yield {b'name': mangle(name)}, f
        yield unmangle(f.value)


class serverrepo(object):
    def __init__(self, ui):
        self.ui = ui

    def greet(self, name):
        return b"Hello, " + name

    def filtered(self, name):
        return self


def mangle(s):
    return b''.join(pycompat.bytechr(ord(c) + 1) for c in pycompat.bytestr(s))


def unmangle(s):
    return b''.join(pycompat.bytechr(ord(c) - 1) for c in pycompat.bytestr(s))


def greet(repo, proto, name):
    return mangle(repo.greet(unmangle(name)))


wireprotov1server.commands[b'greet'] = (greet, b'name')

srv = serverrepo(uimod.ui())
clt = clientpeer(srv, uimod.ui())


def printb(data, end=b'\n'):
    out = getattr(sys.stdout, 'buffer', sys.stdout)
    out.write(data + end)
    out.flush()


printb(clt.greet(b"Foobar"))

with clt.commandexecutor() as e:
    fgreet1 = e.callcommand(b'greet', {b'name': b'Fo, =;:<o'})
    fgreet2 = e.callcommand(b'greet', {b'name': b'Bar'})

printb(
    stringutil.pprint([f.result() for f in (fgreet1, fgreet2)], bprefix=True)
)