sshpeer: remove support for connecting to <0.9.1 servers (BC)

197d10e157ce made this change for the HTTP peer. Let's do the same
for the SSH peer.

Test output changes as expected. A redundant test has been dropped.

.. bc::

   Support for connecting to Mercurial servers older than 0.9.1 has
   been removed.

Differential Revision: https://phab.mercurial-scm.org/D2036

mercurial/sshpeer.py

@@ -1,456 +1,466 b''
 # sshpeer.py - ssh repository proxy class for mercurial
 #
 # Copyright 2005, 2006 Matt Mackall <[e-mail]>
 #
 # 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
 
 import re
 
 from .i18n import _
 from . import (
     error,
     pycompat,
     util,
     wireproto,
 )
 
 def _serverquote(s):
     """quote a string for the remote shell ... which we assume is sh"""
     if not s:
         return s
     if re.match('[a-zA-Z0-9@%_+=:,./-]*$', s):
         return s
     return "'%s'" % s.replace("'", "'\\''")
 
 def _forwardoutput(ui, pipe):
     """display all data currently available on pipe as remote output.
 
     This is non blocking."""
     s = util.readpipe(pipe)
     if s:
         for l in s.splitlines():
             ui.status(_("remote: "), l, '\n')
 
 class doublepipe(object):
     """Operate a side-channel pipe in addition of a main one
 
     The side-channel pipe contains server output to be forwarded to the user
     input. The double pipe will behave as the "main" pipe, but will ensure the
     content of the "side" pipe is properly processed while we wait for blocking
     call on the "main" pipe.
 
     If large amounts of data are read from "main", the forward will cease after
     the first bytes start to appear. This simplifies the implementation
     without affecting actual output of sshpeer too much as we rarely issue
     large read for data not yet emitted by the server.
 
     The main pipe is expected to be a 'bufferedinputpipe' from the util module
     that handle all the os specific bits. This class lives in this module
     because it focus on behavior specific to the ssh protocol."""
 
     def __init__(self, ui, main, side):
         self._ui = ui
         self._main = main
         self._side = side
 
     def _wait(self):
         """wait until some data are available on main or side
 
         return a pair of boolean (ismainready, issideready)
 
         (This will only wait for data if the setup is supported by `util.poll`)
         """
         if getattr(self._main, 'hasbuffer', False): # getattr for classic pipe
             return (True, True) # main has data, assume side is worth poking at.
         fds = [self._main.fileno(), self._side.fileno()]
         try:
             act = util.poll(fds)
         except NotImplementedError:
             # non supported yet case, assume all have data.
             act = fds
         return (self._main.fileno() in act, self._side.fileno() in act)
 
     def write(self, data):
         return self._call('write', data)
 
     def read(self, size):
         r = self._call('read', size)
         if size != 0 and not r:
             # We've observed a condition that indicates the
             # stdout closed unexpectedly. Check stderr one
             # more time and snag anything that's there before
             # letting anyone know the main part of the pipe
             # closed prematurely.
             _forwardoutput(self._ui, self._side)
         return r
 
     def readline(self):
         return self._call('readline')
 
     def _call(self, methname, data=None):
         """call <methname> on "main", forward output of "side" while blocking
         """
         # data can be '' or 0
         if (data is not None and not data) or self._main.closed:
             _forwardoutput(self._ui, self._side)
             return ''
         while True:
             mainready, sideready = self._wait()
             if sideready:
                 _forwardoutput(self._ui, self._side)
             if mainready:
                 meth = getattr(self._main, methname)
                 if data is None:
                     return meth()
                 else:
                     return meth(data)
 
     def close(self):
         return self._main.close()
 
     def flush(self):
         return self._main.flush()
 
 def _cleanuppipes(ui, pipei, pipeo, pipee):
     """Clean up pipes used by an SSH connection."""
     if pipeo:
         pipeo.close()
     if pipei:
         pipei.close()
 
     if pipee:
         # Try to read from the err descriptor until EOF.
         try:
             for l in pipee:
                 ui.status(_('remote: '), l)
         except (IOError, ValueError):
             pass
 
         pipee.close()
 
 def _makeconnection(ui, sshcmd, args, remotecmd, path, sshenv=None):
     """Create an SSH connection to a server.
 
     Returns a tuple of (process, stdin, stdout, stderr) for the
     spawned process.
     """
     cmd = '%s %s %s' % (
         sshcmd,
         args,
         util.shellquote('%s -R %s serve --stdio' % (
             _serverquote(remotecmd), _serverquote(path))))
 
     ui.debug('running %s\n' % cmd)
     cmd = util.quotecommand(cmd)
 
     # no buffer allow the use of 'select'
     # feel free to remove buffering and select usage when we ultimately
     # move to threading.
     stdin, stdout, stderr, proc = util.popen4(cmd, bufsize=0, env=sshenv)
 
     stdout = doublepipe(ui, util.bufferedinputpipe(stdout), stderr)
     stdin = doublepipe(ui, stdin, stderr)
 
     return proc, stdin, stdout, stderr
 
 def _performhandshake(ui, stdin, stdout, stderr):
     def badresponse():
         msg = _('no suitable response from remote hg')
         hint = ui.config('ui', 'ssherrorhint')
         raise error.RepoError(msg, hint=hint)
 
     # The handshake consists of sending 2 wire protocol commands:
     # ``hello`` and ``between``.
     #
     # The ``hello`` command (which was introduced in Mercurial 0.9.1)
     # instructs the server to advertise its capabilities.
     #
     # The ``between`` command (which has existed in all Mercurial servers
     # for as long as SSH support has existed), asks for the set of revisions
     # between a pair of revisions.
     #
     # The ``between`` command is issued with a request for the null
     # range. If the remote is a Mercurial server, this request will
     # generate a specific response: ``1\n\n``. This represents the
     # wire protocol encoded value for ``\n``. We look for ``1\n\n``
     # in the output stream and know this is the response to ``between``
     # and we're at the end of our handshake reply.
     #
     # The response to the ``hello`` command will be a line with the
     # length of the value returned by that command followed by that
     # value. If the server doesn't support ``hello`` (which should be
     # rare), that line will be ``0\n``. Otherwise, the value will contain
     # RFC 822 like lines. Of these, the ``capabilities:`` line contains
     # the capabilities of the server.
     #
     # In addition to the responses to our command requests, the server
     # may emit "banner" output on stdout. SSH servers are allowed to
     # print messages to stdout on login. Issuing commands on connection
     # allows us to flush this banner output from the server by scanning
     # for output to our well-known ``between`` command. Of course, if
     # the banner contains ``1\n\n``, this will throw off our detection.
 
     requestlog = ui.configbool('devel', 'debug.peer-request')
 
     try:
         pairsarg = '%s-%s' % ('0' * 40, '0' * 40)
         handshake = [
             'hello\n',
             'between\n',
             'pairs %d\n' % len(pairsarg),
             pairsarg,
         ]
 
         if requestlog:
             ui.debug('devel-peer-request: hello\n')
         ui.debug('sending hello command\n')
         if requestlog:
             ui.debug('devel-peer-request: between\n')
             ui.debug('devel-peer-request:   pairs: %d bytes\n' % len(pairsarg))
         ui.debug('sending between command\n')
 
         stdin.write(''.join(handshake))
         stdin.flush()
     except IOError:
         badresponse()
 
     lines = ['', 'dummy']
     max_noise = 500
     while lines[-1] and max_noise:
         try:
             l = stdout.readline()
             _forwardoutput(ui, stderr)
             if lines[-1] == '1\n' and l == '\n':
                 break
             if l:
                 ui.debug('remote: ', l)
             lines.append(l)
             max_noise -= 1
         except IOError:
             badresponse()
     else:
         badresponse()
 
     caps = set()
     for l in reversed(lines):
         # Look for response to ``hello`` command. Scan from the back so
         # we don't misinterpret banner output as the command reply.
         if l.startswith('capabilities:'):
             caps.update(l[:-1].split(':')[1].split())
             break
 
+    # Error if we couldn't find a response to ``hello``. This could
+    # mean:
+    #
+    # 1. Remote isn't a Mercurial server
+    # 2. Remote is a <0.9.1 Mercurial server
+    # 3. Remote is a future Mercurial server that dropped ``hello``
+    #    support.
+    if not caps:
+        badresponse()
+
     return caps
 
 class sshpeer(wireproto.wirepeer):
     def __init__(self, ui, url, proc, stdin, stdout, stderr, caps):
         """Create a peer from an existing SSH connection.
 
         ``proc`` is a handle on the underlying SSH process.
         ``stdin``, ``stdout``, and ``stderr`` are handles on the stdio
         pipes for that process.
         ``caps`` is a set of capabilities supported by the remote.
         """
         self._url = url
         self._ui = ui
         # self._subprocess is unused. Keeping a handle on the process
         # holds a reference and prevents it from being garbage collected.
         self._subprocess = proc
         self._pipeo = stdin
         self._pipei = stdout
         self._pipee = stderr
         self._caps = caps
 
     # Begin of _basepeer interface.
 
     @util.propertycache
     def ui(self):
         return self._ui
 
     def url(self):
         return self._url
 
     def local(self):
         return None
 
     def peer(self):
         return self
 
     def canpush(self):
         return True
 
     def close(self):
         pass
 
     # End of _basepeer interface.
 
     # Begin of _basewirecommands interface.
 
     def capabilities(self):
         return self._caps
 
     # End of _basewirecommands interface.
 
     def _readerr(self):
         _forwardoutput(self.ui, self._pipee)
 
     def _abort(self, exception):
         self._cleanup()
         raise exception
 
     def _cleanup(self):
         _cleanuppipes(self.ui, self._pipei, self._pipeo, self._pipee)
 
     __del__ = _cleanup
 
     def _submitbatch(self, req):
         rsp = self._callstream("batch", cmds=wireproto.encodebatchcmds(req))
         available = self._getamount()
         # TODO this response parsing is probably suboptimal for large
         # batches with large responses.
         toread = min(available, 1024)
         work = rsp.read(toread)
         available -= toread
         chunk = work
         while chunk:
             while ';' in work:
                 one, work = work.split(';', 1)
                 yield wireproto.unescapearg(one)
             toread = min(available, 1024)
             chunk = rsp.read(toread)
             available -= toread
             work += chunk
         yield wireproto.unescapearg(work)
 
     def _callstream(self, cmd, **args):
         args = pycompat.byteskwargs(args)
         if (self.ui.debugflag
             and self.ui.configbool('devel', 'debug.peer-request')):
             dbg = self.ui.debug
             line = 'devel-peer-request: %s\n'
             dbg(line % cmd)
             for key, value in sorted(args.items()):
                 if not isinstance(value, dict):
                     dbg(line % '  %s: %d bytes' % (key, len(value)))
                 else:
                     for dk, dv in sorted(value.items()):
                         dbg(line % '  %s-%s: %d' % (key, dk, len(dv)))
         self.ui.debug("sending %s command\n" % cmd)
         self._pipeo.write("%s\n" % cmd)
         _func, names = wireproto.commands[cmd]
         keys = names.split()
         wireargs = {}
         for k in keys:
             if k == '*':
                 wireargs['*'] = args
                 break
             else:
                 wireargs[k] = args[k]
                 del args[k]
         for k, v in sorted(wireargs.iteritems()):
             self._pipeo.write("%s %d\n" % (k, len(v)))
             if isinstance(v, dict):
                 for dk, dv in v.iteritems():
                     self._pipeo.write("%s %d\n" % (dk, len(dv)))
                     self._pipeo.write(dv)
             else:
                 self._pipeo.write(v)
         self._pipeo.flush()
 
         return self._pipei
 
     def _callcompressable(self, cmd, **args):
         return self._callstream(cmd, **args)
 
     def _call(self, cmd, **args):
         self._callstream(cmd, **args)
         return self._recv()
 
     def _callpush(self, cmd, fp, **args):
         r = self._call(cmd, **args)
         if r:
             return '', r
         for d in iter(lambda: fp.read(4096), ''):
             self._send(d)
         self._send("", flush=True)
         r = self._recv()
         if r:
             return '', r
         return self._recv(), ''
 
     def _calltwowaystream(self, cmd, fp, **args):
         r = self._call(cmd, **args)
         if r:
             # XXX needs to be made better
             raise error.Abort(_('unexpected remote reply: %s') % r)
         for d in iter(lambda: fp.read(4096), ''):
             self._send(d)
         self._send("", flush=True)
         return self._pipei
 
     def _getamount(self):
         l = self._pipei.readline()
         if l == '\n':
             self._readerr()
             msg = _('check previous remote output')
             self._abort(error.OutOfBandError(hint=msg))
         self._readerr()
         try:
             return int(l)
         except ValueError:
             self._abort(error.ResponseError(_("unexpected response:"), l))
 
     def _recv(self):
         return self._pipei.read(self._getamount())
 
     def _send(self, data, flush=False):
         self._pipeo.write("%d\n" % len(data))
         if data:
             self._pipeo.write(data)
         if flush:
             self._pipeo.flush()
         self._readerr()
 
 def instance(ui, path, create):
     """Create an SSH peer.
 
     The returned object conforms to the ``wireproto.wirepeer`` interface.
     """
     u = util.url(path, parsequery=False, parsefragment=False)
     if u.scheme != 'ssh' or not u.host or u.path is None:
         raise error.RepoError(_("couldn't parse location %s") % path)
 
     util.checksafessh(path)
 
     if u.passwd is not None:
         raise error.RepoError(_('password in URL not supported'))
 
     sshcmd = ui.config('ui', 'ssh')
     remotecmd = ui.config('ui', 'remotecmd')
     sshaddenv = dict(ui.configitems('sshenv'))
     sshenv = util.shellenviron(sshaddenv)
     remotepath = u.path or '.'
 
     args = util.sshargs(sshcmd, u.host, u.user, u.port)
 
     if create:
         cmd = '%s %s %s' % (sshcmd, args,
             util.shellquote('%s init %s' %
                 (_serverquote(remotecmd), _serverquote(remotepath))))
         ui.debug('running %s\n' % cmd)
         res = ui.system(cmd, blockedtag='sshpeer', environ=sshenv)
         if res != 0:
             raise error.RepoError(_('could not create remote repo'))
 
     proc, stdin, stdout, stderr = _makeconnection(ui, sshcmd, args, remotecmd,
                                                   remotepath, sshenv)
 
     try:
         caps = _performhandshake(ui, stdin, stdout, stderr)
     except Exception:
         _cleanuppipes(ui, stdout, stdin, stderr)
         raise
 
     return sshpeer(ui, path, proc, stdin, stdout, stderr, caps)

tests/test-ssh-proto.t

@@ -1,394 +1,390 b''
   $ cat >> $HGRCPATH << EOF
   > [ui]
   > ssh = $PYTHON "$TESTDIR/dummyssh"
   > [devel]
   > debug.peer-request = true
   > [extensions]
   > sshprotoext = $TESTDIR/sshprotoext.py
   > EOF
 
   $ hg init server
   $ cd server
   $ echo 0 > foo
   $ hg -q add foo
   $ hg commit -m initial
   $ cd ..
 
 Test a normal behaving server, for sanity
 
   $ hg --debug debugpeer ssh://user@dummy/server
   running * "*/tests/dummyssh" 'user@dummy' 'hg -R server serve --stdio' (glob)
   devel-peer-request: hello
   sending hello command
   devel-peer-request: between
   devel-peer-request:   pairs: 81 bytes
   sending between command
   remote: 384
   remote: capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
   remote: 1
   url: ssh://user@dummy/server
   local: no
   pushable: yes
 
 Server should answer the "hello" command in isolation
 
   $ hg -R server serve --stdio << EOF
   > hello
   > EOF
   384
   capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
 
 >=0.9.1 clients send a "hello" + "between" for the null range as part of handshake.
 Server should reply with capabilities and should send "1\n\n" as a successful
 reply with empty response to the "between".
 
   $ hg -R server serve --stdio << EOF
   > hello
   > between
   > pairs 81
   > 0000000000000000000000000000000000000000-0000000000000000000000000000000000000000
   > EOF
   384
   capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
   1
   
 
 SSH banner is not printed by default, ignored by clients
 
   $ SSHSERVERMODE=banner hg debugpeer ssh://user@dummy/server
   url: ssh://user@dummy/server
   local: no
   pushable: yes
 
 --debug will print the banner
 
   $ SSHSERVERMODE=banner hg --debug debugpeer ssh://user@dummy/server
   running * "*/tests/dummyssh" 'user@dummy' 'hg -R server serve --stdio' (glob)
   devel-peer-request: hello
   sending hello command
   devel-peer-request: between
   devel-peer-request:   pairs: 81 bytes
   sending between command
   remote: banner: line 0
   remote: banner: line 1
   remote: banner: line 2
   remote: banner: line 3
   remote: banner: line 4
   remote: banner: line 5
   remote: banner: line 6
   remote: banner: line 7
   remote: banner: line 8
   remote: banner: line 9
   remote: 384
   remote: capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
   remote: 1
   url: ssh://user@dummy/server
   local: no
   pushable: yes
 
 And test the banner with the raw protocol
 
   $ SSHSERVERMODE=banner hg -R server serve --stdio << EOF
   > hello
   > between
   > pairs 81
   > 0000000000000000000000000000000000000000-0000000000000000000000000000000000000000
   > EOF
   banner: line 0
   banner: line 1
   banner: line 2
   banner: line 3
   banner: line 4
   banner: line 5
   banner: line 6
   banner: line 7
   banner: line 8
   banner: line 9
   384
   capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
   1
   
 
-Connecting to a <0.9.1 server that doesn't support the hello command
+Connecting to a <0.9.1 server that doesn't support the hello command.
+The client should refuse, as we dropped support for connecting to such
+servers.
 
   $ SSHSERVERMODE=no-hello hg --debug debugpeer ssh://user@dummy/server
   running * "*/tests/dummyssh" 'user@dummy' 'hg -R server serve --stdio' (glob)
   devel-peer-request: hello
   sending hello command
   devel-peer-request: between
   devel-peer-request:   pairs: 81 bytes
   sending between command
   remote: 0
   remote: 1
-  url: ssh://user@dummy/server
-  local: no
-  pushable: yes
-
-The client should interpret this as no capabilities
-
-  $ SSHSERVERMODE=no-hello hg debugcapabilities ssh://user@dummy/server
-  Main capabilities:
+  abort: no suitable response from remote hg!
+  [255]
 
 Sending an unknown command to the server results in an empty response to that command
 
   $ hg -R server serve --stdio << EOF
   > pre-hello
   > hello
   > between
   > pairs 81
   > 0000000000000000000000000000000000000000-0000000000000000000000000000000000000000
   > EOF
   0
   384
   capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
   1
   
 
   $ hg --config sshpeer.mode=extra-handshake-commands --config sshpeer.handshake-mode=pre-no-args --debug debugpeer ssh://user@dummy/server
   running * "*/tests/dummyssh" 'user@dummy' 'hg -R server serve --stdio' (glob)
   sending no-args command
   devel-peer-request: hello
   sending hello command
   devel-peer-request: between
   devel-peer-request:   pairs: 81 bytes
   sending between command
   remote: 0
   remote: 384
   remote: capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
   remote: 1
   url: ssh://user@dummy/server
   local: no
   pushable: yes
 
 Send multiple unknown commands before hello
 
   $ hg -R server serve --stdio << EOF
   > unknown1
   > unknown2
   > unknown3
   > hello
   > between
   > pairs 81
   > 0000000000000000000000000000000000000000-0000000000000000000000000000000000000000
   > EOF
   0
   0
   0
   384
   capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
   1
   
 
   $ hg --config sshpeer.mode=extra-handshake-commands --config sshpeer.handshake-mode=pre-multiple-no-args --debug debugpeer ssh://user@dummy/server
   running * "*/tests/dummyssh" 'user@dummy' 'hg -R server serve --stdio' (glob)
   sending unknown1 command
   sending unknown2 command
   sending unknown3 command
   devel-peer-request: hello
   sending hello command
   devel-peer-request: between
   devel-peer-request:   pairs: 81 bytes
   sending between command
   remote: 0
   remote: 0
   remote: 0
   remote: 384
   remote: capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
   remote: 1
   url: ssh://user@dummy/server
   local: no
   pushable: yes
 
 Send an unknown command before hello that has arguments
 
   $ hg -R server serve --stdio << EOF
   > with-args
   > foo 13
   > value for foo
   > bar 13
   > value for bar
   > hello
   > between
   > pairs 81
   > 0000000000000000000000000000000000000000-0000000000000000000000000000000000000000
   > EOF
   0
   0
   0
   0
   0
   384
   capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
   1
   
 
 Send an unknown command having an argument that looks numeric
 
   $ hg -R server serve --stdio << EOF
   > unknown
   > foo 1
   > 0
   > hello
   > between
   > pairs 81
   > 0000000000000000000000000000000000000000-0000000000000000000000000000000000000000
   > EOF
   0
   0
   0
   384
   capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
   1
   
 
   $ hg -R server serve --stdio << EOF
   > unknown
   > foo 1
   > 1
   > hello
   > between
   > pairs 81
   > 0000000000000000000000000000000000000000-0000000000000000000000000000000000000000
   > EOF
   0
   0
   0
   384
   capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
   1
   
 
 When sending a dict argument value, it is serialized to
 "<arg> <item count>" followed by "<key> <len>\n<value>" for each item
 in the dict.
 
 Dictionary value for unknown command
 
   $ hg -R server serve --stdio << EOF
   > unknown
   > dict 3
   > key1 3
   > foo
   > key2 3
   > bar
   > key3 3
   > baz
   > hello
   > EOF
   0
   0
   0
   0
   0
   0
   0
   0
   384
   capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
 
 Incomplete dictionary send
 
   $ hg -R server serve --stdio << EOF
   > unknown
   > dict 3
   > key1 3
   > foo
   > EOF
   0
   0
   0
   0
 
 Incomplete value send
 
   $ hg -R server serve --stdio << EOF
   > unknown
   > dict 3
   > key1 3
   > fo
   > EOF
   0
   0
   0
   0
 
 Send a command line with spaces
 
   $ hg -R server serve --stdio << EOF
   > unknown withspace
   > hello
   > between
   > pairs 81
   > 0000000000000000000000000000000000000000-0000000000000000000000000000000000000000
   > EOF
   0
   384
   capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
   1
   
 
   $ hg -R server serve --stdio << EOF
   > unknown with multiple spaces
   > hello
   > between
   > pairs 81
   > 0000000000000000000000000000000000000000-0000000000000000000000000000000000000000
   > EOF
   0
   384
   capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
   1
   
 
   $ hg -R server serve --stdio << EOF
   > unknown with spaces
   > key 10
   > some value
   > hello
   > between
   > pairs 81
   > 0000000000000000000000000000000000000000-0000000000000000000000000000000000000000
   > EOF
   0
   0
   0
   384
   capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
   1
   
 
 Send an unknown command after the "between"
 
   $ hg -R server serve --stdio << EOF
   > hello
   > between
   > pairs 81
   > 0000000000000000000000000000000000000000-0000000000000000000000000000000000000000unknown
   > EOF
   384
   capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
   1
   
   0
 
 And one with arguments
 
   $ hg -R server serve --stdio << EOF
   > hello
   > between
   > pairs 81
   > 0000000000000000000000000000000000000000-0000000000000000000000000000000000000000unknown
   > foo 5
   > value
   > bar 3
   > baz
   > EOF
   384
   capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
   1
   
   0
   0
   0
   0
   0