view tests/test-wireproto.py @ 42943:5fadf6103790

remotefilelog: replace repack lock to solve race condition

2c74337e6483 reduced the probability of race-conditions when starting
background repack and prefetch and we saw the difference in our CI instance
with all failures disappearing except one where one call to waitonrepack seems
to returns too early.

I'm not sure what exactly goes wrong but I realized that while the prefetch
operation uses a standard Mercurial lock, the repack operation is using a
custom lock based on `fcntl.flock` on available platforms. As `extutil.flock`
fallback on traditional Mercurial locks on other platforms and the tests are
stable on my laptop, our CI environment and GCC112, I'm sending this patch to
standardize the behavior across environments.

Differential Revision: https://phab.mercurial-scm.org/D6844

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))