CONTRIBUTORS

wireproto: in batch queries, support queries with immediate responses

listkeys and pushkey return without querying the remote when the
remote doesn't support such queries. Before this change, the batching
code didn't handle this convention, resulting in this kind of error:

  $ hg pull ssh://user@dummy/repo1 -r tip -B a
  pulling from ssh://user@dummy/repo1
  remote: ** Unknown exception encountered with possibly-broken third-party extension disable-lookup
  remote: ** which supports versions unknown of Mercurial.
  remote: ** Please disable disable-lookup and try your action again.
  remote: ** If that fixes the bug please report it to the extension author.
  remote: ** Python 2.7.15+ (default, Oct  2 2018, 22:12:08) [GCC 8.2.0]
  remote: ** Mercurial Distributed SCM (version 4.8.1+586-ef54bd33b476+20181224)
  remote: ** Extensions loaded: disable-lookup
  remote: Traceback (most recent call last):
  remote:   File "/tmp/hgtests.i66Npc/install/bin/hg", line 43, in <module>
  remote:     dispatch.run()
  remote:   File "/tmp/hgtests.i66Npc/install/lib/python/mercurial/dispatch.py", line 99, in run
  remote:     status = dispatch(req)
  remote:   File "/tmp/hgtests.i66Npc/install/lib/python/mercurial/dispatch.py", line 225, in dispatch
  remote:     ret = _runcatch(req) or 0
  remote:   File "/tmp/hgtests.i66Npc/install/lib/python/mercurial/dispatch.py", line 376, in _runcatch
  remote:     return _callcatch(ui, _runcatchfunc)
  remote:   File "/tmp/hgtests.i66Npc/install/lib/python/mercurial/dispatch.py", line 384, in _callcatch
  remote:     return scmutil.callcatch(ui, func)
  remote:   File "/tmp/hgtests.i66Npc/install/lib/python/mercurial/scmutil.py", line 166, in callcatch
  remote:     return func()
  remote:   File "/tmp/hgtests.i66Npc/install/lib/python/mercurial/dispatch.py", line 367, in _runcatchfunc
  remote:     return _dispatch(req)
  remote:   File "/tmp/hgtests.i66Npc/install/lib/python/mercurial/dispatch.py", line 1021, in _dispatch
  remote:     cmdpats, cmdoptions)
  remote:   File "/tmp/hgtests.i66Npc/install/lib/python/mercurial/dispatch.py", line 756, in runcommand
  remote:     ret = _runcommand(ui, options, cmd, d)
  remote:   File "/tmp/hgtests.i66Npc/install/lib/python/mercurial/dispatch.py", line 1030, in _runcommand
  remote:     return cmdfunc()
  remote:   File "/tmp/hgtests.i66Npc/install/lib/python/mercurial/dispatch.py", line 1018, in <lambda>
  remote:     d = lambda: util.checksignature(func)(ui, *args, **strcmdopt)
  remote:   File "/tmp/hgtests.i66Npc/install/lib/python/mercurial/util.py", line 1670, in check
  remote:     return func(*args, **kwargs)
  remote:   File "/tmp/hgtests.i66Npc/install/lib/python/mercurial/commands.py", line 5257, in serve
  remote:     s.serve_forever()
  remote:   File "/tmp/hgtests.i66Npc/install/lib/python/mercurial/wireprotoserver.py", line 797, in serve_forever
  remote:     self.serveuntil(threading.Event())
  remote:   File "/tmp/hgtests.i66Npc/install/lib/python/mercurial/wireprotoserver.py", line 804, in serveuntil
  remote:     _runsshserver(self._ui, self._repo, self._fin, self._fout, ev)
  remote:   File "/tmp/hgtests.i66Npc/install/lib/python/mercurial/wireprotoserver.py", line 656, in _runsshserver
  remote:     rsp = wireprotov1server.dispatch(repo, proto, request)
  remote:   File "/tmp/hgtests.i66Npc/install/lib/python/mercurial/wireprotov1server.py", line 74, in dispatch
  remote:     return func(repo, proto, *args)
  remote:   File "/tmp/hgtests.i66Npc/install/lib/python/mercurial/wireprotov1server.py", line 195, in batch
  remote:     data[k] = vals[k]
  remote: KeyError: 'namespace'
  abort: unexpected response: empty string
  [255]

Differential Revision: https://phab.mercurial-scm.org/D5482

[This file is here for historical purposes, all recent contributors
should appear in the changelog directly]

Andrea Arcangeli <andrea at suse.de>
Thomas Arendsen Hein <thomas at intevation.de>
Goffredo Baroncelli <kreijack at libero.it>
Muli Ben-Yehuda <mulix at mulix.org>
Mikael Berthe <mikael at lilotux.net>
Benoit Boissinot <bboissin at gmail.com>
Brendan Cully <brendan at kublai.com>
Vincent Danjean <vdanjean.ml at free.fr>
Jake Edge <jake at edge2.net>
Michael Fetterman <michael.fetterman at intel.com>
Edouard Gomez <ed.gomez at free.fr>
Eric Hopper <hopper at omnifarious.org>
Alecs King <alecsk at gmail.com>
Volker Kleinfeld <Volker.Kleinfeld at gmx.de>
Vadim Lebedev <vadim at mbdsys.com>
Christopher Li <hg at chrisli.org>
Chris Mason <mason at suse.com>
Colin McMillen <mcmillen at cs.cmu.edu>
Wojciech Milkowski <wmilkowski at interia.pl>
Chad Netzer <chad.netzer at gmail.com>
Bryan O'Sullivan <bos at serpentine.com>
Vicent Seguí Pascual <vseguip at gmail.com>
Sean Perry <shaleh at speakeasy.net>
Nguyen Anh Quynh <aquynh at gmail.com>
Ollivier Robert <roberto at keltia.freenix.fr>
Alexander Schremmer <alex at alexanderweb.de>
Arun Sharma <arun at sharma-home.net>
Josef "Jeff" Sipek <jeffpc at optonline.net>
Kevin Smith <yarcs at qualitycode.com>
TK Soh <teekaysoh at yahoo.com>
Radoslaw Szkodzinski <astralstorm at gorzow.mm.pl>
Samuel Tardieu <sam at rfc1149.net>
K Thananchayan <thananck at yahoo.com>
Andrew Thompson <andrewkt at aktzero.com>
Michael S. Tsirkin <mst at mellanox.co.il>
Rafael Villar Burke <pachi at mmn-arquitectos.com>
Tristan Wibberley <tristan at wibberley.org>
Mark Williamson <mark.williamson at cl.cam.ac.uk>