wireprotov2: re-add tuple around `bundle2` check

I stumbled upon this while looking for the current (v1) `capable` method. It
looks like 9c2c77c73f23 accidentally removed the comma, turning the tuple into
a simple parenthesis expression.

This has not been detected since wireproto2 is not in use AFAIK.

Differential Revision: https://phab.mercurial-scm.org/D9518

mercurial/httppeer.py

@@ -1,1121 +1,1121 b''
 # httppeer.py - HTTP repository proxy classes for mercurial
 #
 # Copyright 2005, 2006 Matt Mackall <[e-mail]>
 # Copyright 2006 Vadim Gelfer <[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 errno
 import io
 import os
 import socket
 import struct
 import weakref
 
 from .i18n import _
 from .pycompat import getattr
 from . import (
     bundle2,
     error,
     httpconnection,
     pycompat,
     statichttprepo,
     url as urlmod,
     util,
     wireprotoframing,
     wireprototypes,
     wireprotov1peer,
     wireprotov2peer,
     wireprotov2server,
 )
 from .interfaces import (
     repository,
     util as interfaceutil,
 )
 from .utils import (
     cborutil,
     stringutil,
 )
 
 httplib = util.httplib
 urlerr = util.urlerr
 urlreq = util.urlreq
 
 
 def encodevalueinheaders(value, header, limit):
     """Encode a string value into multiple HTTP headers.
 
     ``value`` will be encoded into 1 or more HTTP headers with the names
     ``header-<N>`` where ``<N>`` is an integer starting at 1. Each header
     name + value will be at most ``limit`` bytes long.
 
     Returns an iterable of 2-tuples consisting of header names and
     values as native strings.
     """
     # HTTP Headers are ASCII. Python 3 requires them to be unicodes,
     # not bytes. This function always takes bytes in as arguments.
     fmt = pycompat.strurl(header) + r'-%s'
     # Note: it is *NOT* a bug that the last bit here is a bytestring
     # and not a unicode: we're just getting the encoded length anyway,
     # and using an r-string to make it portable between Python 2 and 3
     # doesn't work because then the \r is a literal backslash-r
     # instead of a carriage return.
     valuelen = limit - len(fmt % '000') - len(b': \r\n')
     result = []
 
     n = 0
     for i in pycompat.xrange(0, len(value), valuelen):
         n += 1
         result.append((fmt % str(n), pycompat.strurl(value[i : i + valuelen])))
 
     return result
 
 
 class _multifile(object):
     def __init__(self, *fileobjs):
         for f in fileobjs:
             if not util.safehasattr(f, b'length'):
                 raise ValueError(
                     b'_multifile only supports file objects that '
                     b'have a length but this one does not:',
                     type(f),
                     f,
                 )
         self._fileobjs = fileobjs
         self._index = 0
 
     @property
     def length(self):
         return sum(f.length for f in self._fileobjs)
 
     def read(self, amt=None):
         if amt <= 0:
             return b''.join(f.read() for f in self._fileobjs)
         parts = []
         while amt and self._index < len(self._fileobjs):
             parts.append(self._fileobjs[self._index].read(amt))
             got = len(parts[-1])
             if got < amt:
                 self._index += 1
             amt -= got
         return b''.join(parts)
 
     def seek(self, offset, whence=os.SEEK_SET):
         if whence != os.SEEK_SET:
             raise NotImplementedError(
                 b'_multifile does not support anything other'
                 b' than os.SEEK_SET for whence on seek()'
             )
         if offset != 0:
             raise NotImplementedError(
                 b'_multifile only supports seeking to start, but that '
                 b'could be fixed if you need it'
             )
         for f in self._fileobjs:
             f.seek(0)
         self._index = 0
 
 
 def makev1commandrequest(
     ui, requestbuilder, caps, capablefn, repobaseurl, cmd, args
 ):
     """Make an HTTP request to run a command for a version 1 client.
 
     ``caps`` is a set of known server capabilities. The value may be
     None if capabilities are not yet known.
 
     ``capablefn`` is a function to evaluate a capability.
 
     ``cmd``, ``args``, and ``data`` define the command, its arguments, and
     raw data to pass to it.
     """
     if cmd == b'pushkey':
         args[b'data'] = b''
     data = args.pop(b'data', None)
     headers = args.pop(b'headers', {})
 
     ui.debug(b"sending %s command\n" % cmd)
     q = [(b'cmd', cmd)]
     headersize = 0
     # Important: don't use self.capable() here or else you end up
     # with infinite recursion when trying to look up capabilities
     # for the first time.
     postargsok = caps is not None and b'httppostargs' in caps
 
     # Send arguments via POST.
     if postargsok and args:
         strargs = urlreq.urlencode(sorted(args.items()))
         if not data:
             data = strargs
         else:
             if isinstance(data, bytes):
                 i = io.BytesIO(data)
                 i.length = len(data)
                 data = i
             argsio = io.BytesIO(strargs)
             argsio.length = len(strargs)
             data = _multifile(argsio, data)
         headers['X-HgArgs-Post'] = len(strargs)
     elif args:
         # Calling self.capable() can infinite loop if we are calling
         # "capabilities". But that command should never accept wire
         # protocol arguments. So this should never happen.
         assert cmd != b'capabilities'
         httpheader = capablefn(b'httpheader')
         if httpheader:
             headersize = int(httpheader.split(b',', 1)[0])
 
         # Send arguments via HTTP headers.
         if headersize > 0:
             # The headers can typically carry more data than the URL.
             encargs = urlreq.urlencode(sorted(args.items()))
             for header, value in encodevalueinheaders(
                 encargs, b'X-HgArg', headersize
             ):
                 headers[header] = value
         # Send arguments via query string (Mercurial <1.9).
         else:
             q += sorted(args.items())
 
     qs = b'?%s' % urlreq.urlencode(q)
     cu = b"%s%s" % (repobaseurl, qs)
     size = 0
     if util.safehasattr(data, b'length'):
         size = data.length
     elif data is not None:
         size = len(data)
     if data is not None and 'Content-Type' not in headers:
         headers['Content-Type'] = 'application/mercurial-0.1'
 
     # Tell the server we accept application/mercurial-0.2 and multiple
     # compression formats if the server is capable of emitting those
     # payloads.
     # Note: Keep this set empty by default, as client advertisement of
     # protocol parameters should only occur after the handshake.
     protoparams = set()
 
     mediatypes = set()
     if caps is not None:
         mt = capablefn(b'httpmediatype')
         if mt:
             protoparams.add(b'0.1')
             mediatypes = set(mt.split(b','))
 
         protoparams.add(b'partial-pull')
 
     if b'0.2tx' in mediatypes:
         protoparams.add(b'0.2')
 
     if b'0.2tx' in mediatypes and capablefn(b'compression'):
         # We /could/ compare supported compression formats and prune
         # non-mutually supported or error if nothing is mutually supported.
         # For now, send the full list to the server and have it error.
         comps = [
             e.wireprotosupport().name
             for e in util.compengines.supportedwireengines(util.CLIENTROLE)
         ]
         protoparams.add(b'comp=%s' % b','.join(comps))
 
     if protoparams:
         protoheaders = encodevalueinheaders(
             b' '.join(sorted(protoparams)), b'X-HgProto', headersize or 1024
         )
         for header, value in protoheaders:
             headers[header] = value
 
     varyheaders = []
     for header in headers:
         if header.lower().startswith('x-hg'):
             varyheaders.append(header)
 
     if varyheaders:
         headers['Vary'] = ','.join(sorted(varyheaders))
 
     req = requestbuilder(pycompat.strurl(cu), data, headers)
 
     if data is not None:
         ui.debug(b"sending %d bytes\n" % size)
         req.add_unredirected_header('Content-Length', '%d' % size)
 
     return req, cu, qs
 
 
 def _reqdata(req):
     """Get request data, if any. If no data, returns None."""
     if pycompat.ispy3:
         return req.data
     if not req.has_data():
         return None
     return req.get_data()
 
 
 def sendrequest(ui, opener, req):
     """Send a prepared HTTP request.
 
     Returns the response object.
     """
     dbg = ui.debug
     if ui.debugflag and ui.configbool(b'devel', b'debug.peer-request'):
         line = b'devel-peer-request: %s\n'
         dbg(
             line
             % b'%s %s'
             % (
                 pycompat.bytesurl(req.get_method()),
                 pycompat.bytesurl(req.get_full_url()),
             )
         )
         hgargssize = None
 
         for header, value in sorted(req.header_items()):
             header = pycompat.bytesurl(header)
             value = pycompat.bytesurl(value)
             if header.startswith(b'X-hgarg-'):
                 if hgargssize is None:
                     hgargssize = 0
                 hgargssize += len(value)
             else:
                 dbg(line % b'  %s %s' % (header, value))
 
         if hgargssize is not None:
             dbg(
                 line
                 % b'  %d bytes of commands arguments in headers'
                 % hgargssize
             )
         data = _reqdata(req)
         if data is not None:
             length = getattr(data, 'length', None)
             if length is None:
                 length = len(data)
             dbg(line % b'  %d bytes of data' % length)
 
         start = util.timer()
 
     res = None
     try:
         res = opener.open(req)
     except urlerr.httperror as inst:
         if inst.code == 401:
             raise error.Abort(_(b'authorization failed'))
         raise
     except httplib.HTTPException as inst:
         ui.debug(
             b'http error requesting %s\n'
             % util.hidepassword(req.get_full_url())
         )
         ui.traceback()
         raise IOError(None, inst)
     finally:
         if ui.debugflag and ui.configbool(b'devel', b'debug.peer-request'):
             code = res.code if res else -1
             dbg(
                 line
                 % b'  finished in %.4f seconds (%d)'
                 % (util.timer() - start, code)
             )
 
     # Insert error handlers for common I/O failures.
     urlmod.wrapresponse(res)
 
     return res
 
 
 class RedirectedRepoError(error.RepoError):
     def __init__(self, msg, respurl):
         super(RedirectedRepoError, self).__init__(msg)
         self.respurl = respurl
 
 
 def parsev1commandresponse(
     ui, baseurl, requrl, qs, resp, compressible, allowcbor=False
 ):
     # record the url we got redirected to
     redirected = False
     respurl = pycompat.bytesurl(resp.geturl())
     if respurl.endswith(qs):
         respurl = respurl[: -len(qs)]
         qsdropped = False
     else:
         qsdropped = True
 
     if baseurl.rstrip(b'/') != respurl.rstrip(b'/'):
         redirected = True
         if not ui.quiet:
             ui.warn(_(b'real URL is %s\n') % respurl)
 
     try:
         proto = pycompat.bytesurl(resp.getheader('content-type', ''))
     except AttributeError:
         proto = pycompat.bytesurl(resp.headers.get('content-type', ''))
 
     safeurl = util.hidepassword(baseurl)
     if proto.startswith(b'application/hg-error'):
         raise error.OutOfBandError(resp.read())
 
     # Pre 1.0 versions of Mercurial used text/plain and
     # application/hg-changegroup. We don't support such old servers.
     if not proto.startswith(b'application/mercurial-'):
         ui.debug(b"requested URL: '%s'\n" % util.hidepassword(requrl))
         msg = _(
             b"'%s' does not appear to be an hg repository:\n"
             b"---%%<--- (%s)\n%s\n---%%<---\n"
         ) % (safeurl, proto or b'no content-type', resp.read(1024))
 
         # Some servers may strip the query string from the redirect. We
         # raise a special error type so callers can react to this specially.
         if redirected and qsdropped:
             raise RedirectedRepoError(msg, respurl)
         else:
             raise error.RepoError(msg)
 
     try:
         subtype = proto.split(b'-', 1)[1]
 
         # Unless we end up supporting CBOR in the legacy wire protocol,
         # this should ONLY be encountered for the initial capabilities
         # request during handshake.
         if subtype == b'cbor':
             if allowcbor:
                 return respurl, proto, resp
             else:
                 raise error.RepoError(
                     _(b'unexpected CBOR response from server')
                 )
 
         version_info = tuple([int(n) for n in subtype.split(b'.')])
     except ValueError:
         raise error.RepoError(
             _(b"'%s' sent a broken Content-Type header (%s)") % (safeurl, proto)
         )
 
     # TODO consider switching to a decompression reader that uses
     # generators.
     if version_info == (0, 1):
         if compressible:
             resp = util.compengines[b'zlib'].decompressorreader(resp)
 
     elif version_info == (0, 2):
         # application/mercurial-0.2 always identifies the compression
         # engine in the payload header.
         elen = struct.unpack(b'B', util.readexactly(resp, 1))[0]
         ename = util.readexactly(resp, elen)
         engine = util.compengines.forwiretype(ename)
 
         resp = engine.decompressorreader(resp)
     else:
         raise error.RepoError(
             _(b"'%s' uses newer protocol %s") % (safeurl, subtype)
         )
 
     return respurl, proto, resp
 
 
 class httppeer(wireprotov1peer.wirepeer):
     def __init__(self, ui, path, url, opener, requestbuilder, caps):
         self.ui = ui
         self._path = path
         self._url = url
         self._caps = caps
         self.limitedarguments = caps is not None and b'httppostargs' not in caps
         self._urlopener = opener
         self._requestbuilder = requestbuilder
 
     def __del__(self):
         for h in self._urlopener.handlers:
             h.close()
             getattr(h, "close_all", lambda: None)()
 
     # Begin of ipeerconnection interface.
 
     def url(self):
         return self._path
 
     def local(self):
         return None
 
     def peer(self):
         return self
 
     def canpush(self):
         return True
 
     def close(self):
         try:
             reqs, sent, recv = (
                 self._urlopener.requestscount,
                 self._urlopener.sentbytescount,
                 self._urlopener.receivedbytescount,
             )
         except AttributeError:
             return
         self.ui.note(
             _(
                 b'(sent %d HTTP requests and %d bytes; '
                 b'received %d bytes in responses)\n'
             )
             % (reqs, sent, recv)
         )
 
     # End of ipeerconnection interface.
 
     # Begin of ipeercommands interface.
 
     def capabilities(self):
         return self._caps
 
     # End of ipeercommands interface.
 
     def _callstream(self, cmd, _compressible=False, **args):
         args = pycompat.byteskwargs(args)
 
         req, cu, qs = makev1commandrequest(
             self.ui,
             self._requestbuilder,
             self._caps,
             self.capable,
             self._url,
             cmd,
             args,
         )
 
         resp = sendrequest(self.ui, self._urlopener, req)
 
         self._url, ct, resp = parsev1commandresponse(
             self.ui, self._url, cu, qs, resp, _compressible
         )
 
         return resp
 
     def _call(self, cmd, **args):
         fp = self._callstream(cmd, **args)
         try:
             return fp.read()
         finally:
             # if using keepalive, allow connection to be reused
             fp.close()
 
     def _callpush(self, cmd, cg, **args):
         # have to stream bundle to a temp file because we do not have
         # http 1.1 chunked transfer.
 
         types = self.capable(b'unbundle')
         try:
             types = types.split(b',')
         except AttributeError:
             # servers older than d1b16a746db6 will send 'unbundle' as a
             # boolean capability. They only support headerless/uncompressed
             # bundles.
             types = [b""]
         for x in types:
             if x in bundle2.bundletypes:
                 type = x
                 break
 
         tempname = bundle2.writebundle(self.ui, cg, None, type)
         fp = httpconnection.httpsendfile(self.ui, tempname, b"rb")
         headers = {'Content-Type': 'application/mercurial-0.1'}
 
         try:
             r = self._call(cmd, data=fp, headers=headers, **args)
             vals = r.split(b'\n', 1)
             if len(vals) < 2:
                 raise error.ResponseError(_(b"unexpected response:"), r)
             return vals
         except urlerr.httperror:
             # Catch and re-raise these so we don't try and treat them
             # like generic socket errors. They lack any values in
             # .args on Python 3 which breaks our socket.error block.
             raise
         except socket.error as err:
             if err.args[0] in (errno.ECONNRESET, errno.EPIPE):
                 raise error.Abort(_(b'push failed: %s') % err.args[1])
             raise error.Abort(err.args[1])
         finally:
             fp.close()
             os.unlink(tempname)
 
     def _calltwowaystream(self, cmd, fp, **args):
         filename = None
         try:
             # dump bundle to disk
             fd, filename = pycompat.mkstemp(prefix=b"hg-bundle-", suffix=b".hg")
             with os.fdopen(fd, "wb") as fh:
                 d = fp.read(4096)
                 while d:
                     fh.write(d)
                     d = fp.read(4096)
             # start http push
             with httpconnection.httpsendfile(self.ui, filename, b"rb") as fp_:
                 headers = {'Content-Type': 'application/mercurial-0.1'}
                 return self._callstream(cmd, data=fp_, headers=headers, **args)
         finally:
             if filename is not None:
                 os.unlink(filename)
 
     def _callcompressable(self, cmd, **args):
         return self._callstream(cmd, _compressible=True, **args)
 
     def _abort(self, exception):
         raise exception
 
 
 def sendv2request(
     ui, opener, requestbuilder, apiurl, permission, requests, redirect
 ):
     wireprotoframing.populatestreamencoders()
 
     uiencoders = ui.configlist(b'experimental', b'httppeer.v2-encoder-order')
 
     if uiencoders:
         encoders = []
 
         for encoder in uiencoders:
             if encoder not in wireprotoframing.STREAM_ENCODERS:
                 ui.warn(
                     _(
                         b'wire protocol version 2 encoder referenced in '
                         b'config (%s) is not known; ignoring\n'
                     )
                     % encoder
                 )
             else:
                 encoders.append(encoder)
 
     else:
         encoders = wireprotoframing.STREAM_ENCODERS_ORDER
 
     reactor = wireprotoframing.clientreactor(
         ui,
         hasmultiplesend=False,
         buffersends=True,
         clientcontentencoders=encoders,
     )
 
     handler = wireprotov2peer.clienthandler(
         ui, reactor, opener=opener, requestbuilder=requestbuilder
     )
 
     url = b'%s/%s' % (apiurl, permission)
 
     if len(requests) > 1:
         url += b'/multirequest'
     else:
         url += b'/%s' % requests[0][0]
 
     ui.debug(b'sending %d commands\n' % len(requests))
     for command, args, f in requests:
         ui.debug(
             b'sending command %s: %s\n'
             % (command, stringutil.pprint(args, indent=2))
         )
         assert not list(
             handler.callcommand(command, args, f, redirect=redirect)
         )
 
     # TODO stream this.
     body = b''.join(map(bytes, handler.flushcommands()))
 
     # TODO modify user-agent to reflect v2
     headers = {
         'Accept': wireprotov2server.FRAMINGTYPE,
         'Content-Type': wireprotov2server.FRAMINGTYPE,
     }
 
     req = requestbuilder(pycompat.strurl(url), body, headers)
     req.add_unredirected_header('Content-Length', '%d' % len(body))
 
     try:
         res = opener.open(req)
     except urlerr.httperror as e:
         if e.code == 401:
             raise error.Abort(_(b'authorization failed'))
 
         raise
     except httplib.HTTPException as e:
         ui.traceback()
         raise IOError(None, e)
 
     return handler, res
 
 
 class queuedcommandfuture(pycompat.futures.Future):
     """Wraps result() on command futures to trigger submission on call."""
 
     def result(self, timeout=None):
         if self.done():
             return pycompat.futures.Future.result(self, timeout)
 
         self._peerexecutor.sendcommands()
 
         # sendcommands() will restore the original __class__ and self.result
         # will resolve to Future.result.
         return self.result(timeout)
 
 
 @interfaceutil.implementer(repository.ipeercommandexecutor)
 class httpv2executor(object):
     def __init__(
         self, ui, opener, requestbuilder, apiurl, descriptor, redirect
     ):
         self._ui = ui
         self._opener = opener
         self._requestbuilder = requestbuilder
         self._apiurl = apiurl
         self._descriptor = descriptor
         self._redirect = redirect
         self._sent = False
         self._closed = False
         self._neededpermissions = set()
         self._calls = []
         self._futures = weakref.WeakSet()
         self._responseexecutor = None
         self._responsef = None
 
     def __enter__(self):
         return self
 
     def __exit__(self, exctype, excvalue, exctb):
         self.close()
 
     def callcommand(self, command, args):
         if self._sent:
             raise error.ProgrammingError(
                 b'callcommand() cannot be used after commands are sent'
             )
 
         if self._closed:
             raise error.ProgrammingError(
                 b'callcommand() cannot be used after close()'
             )
 
         # The service advertises which commands are available. So if we attempt
         # to call an unknown command or pass an unknown argument, we can screen
         # for this.
         if command not in self._descriptor[b'commands']:
             raise error.ProgrammingError(
                 b'wire protocol command %s is not available' % command
             )
 
         cmdinfo = self._descriptor[b'commands'][command]
         unknownargs = set(args.keys()) - set(cmdinfo.get(b'args', {}))
 
         if unknownargs:
             raise error.ProgrammingError(
                 b'wire protocol command %s does not accept argument: %s'
                 % (command, b', '.join(sorted(unknownargs)))
             )
 
         self._neededpermissions |= set(cmdinfo[b'permissions'])
 
         # TODO we /could/ also validate types here, since the API descriptor
         # includes types...
 
         f = pycompat.futures.Future()
 
         # Monkeypatch it so result() triggers sendcommands(), otherwise result()
         # could deadlock.
         f.__class__ = queuedcommandfuture
         f._peerexecutor = self
 
         self._futures.add(f)
         self._calls.append((command, args, f))
 
         return f
 
     def sendcommands(self):
         if self._sent:
             return
 
         if not self._calls:
             return
 
         self._sent = True
 
         # Unhack any future types so caller sees a clean type and so we
         # break reference cycle.
         for f in self._futures:
             if isinstance(f, queuedcommandfuture):
                 f.__class__ = pycompat.futures.Future
                 f._peerexecutor = None
 
         # Mark the future as running and filter out cancelled futures.
         calls = [
             (command, args, f)
             for command, args, f in self._calls
             if f.set_running_or_notify_cancel()
         ]
 
         # Clear out references, prevent improper object usage.
         self._calls = None
 
         if not calls:
             return
 
         permissions = set(self._neededpermissions)
 
         if b'push' in permissions and b'pull' in permissions:
             permissions.remove(b'pull')
 
         if len(permissions) > 1:
             raise error.RepoError(
                 _(b'cannot make request requiring multiple permissions: %s')
                 % _(b', ').join(sorted(permissions))
             )
 
         permission = {
             b'push': b'rw',
             b'pull': b'ro',
         }[permissions.pop()]
 
         handler, resp = sendv2request(
             self._ui,
             self._opener,
             self._requestbuilder,
             self._apiurl,
             permission,
             calls,
             self._redirect,
         )
 
         # TODO we probably want to validate the HTTP code, media type, etc.
 
         self._responseexecutor = pycompat.futures.ThreadPoolExecutor(1)
         self._responsef = self._responseexecutor.submit(
             self._handleresponse, handler, resp
         )
 
     def close(self):
         if self._closed:
             return
 
         self.sendcommands()
 
         self._closed = True
 
         if not self._responsef:
             return
 
         # TODO ^C here may not result in immediate program termination.
 
         try:
             self._responsef.result()
         finally:
             self._responseexecutor.shutdown(wait=True)
             self._responsef = None
             self._responseexecutor = None
 
             # If any of our futures are still in progress, mark them as
             # errored, otherwise a result() could wait indefinitely.
             for f in self._futures:
                 if not f.done():
                     f.set_exception(
                         error.ResponseError(_(b'unfulfilled command response'))
                     )
 
             self._futures = None
 
     def _handleresponse(self, handler, resp):
         # Called in a thread to read the response.
 
         while handler.readdata(resp):
             pass
 
 
 @interfaceutil.implementer(repository.ipeerv2)
 class httpv2peer(object):
 
     limitedarguments = False
 
     def __init__(
         self, ui, repourl, apipath, opener, requestbuilder, apidescriptor
     ):
         self.ui = ui
         self.apidescriptor = apidescriptor
 
         if repourl.endswith(b'/'):
             repourl = repourl[:-1]
 
         self._url = repourl
         self._apipath = apipath
         self._apiurl = b'%s/%s' % (repourl, apipath)
         self._opener = opener
         self._requestbuilder = requestbuilder
 
         self._redirect = wireprotov2peer.supportedredirects(ui, apidescriptor)
 
     # Start of ipeerconnection.
 
     def url(self):
         return self._url
 
     def local(self):
         return None
 
     def peer(self):
         return self
 
     def canpush(self):
         # TODO change once implemented.
         return False
 
     def close(self):
         self.ui.note(
             _(
                 b'(sent %d HTTP requests and %d bytes; '
                 b'received %d bytes in responses)\n'
             )
             % (
                 self._opener.requestscount,
                 self._opener.sentbytescount,
                 self._opener.receivedbytescount,
             )
         )
 
     # End of ipeerconnection.
 
     # Start of ipeercapabilities.
 
     def capable(self, name):
         # The capabilities used internally historically map to capabilities
         # advertised from the "capabilities" wire protocol command. However,
         # version 2 of that command works differently.
 
         # Maps to commands that are available.
         if name in (
             b'branchmap',
             b'getbundle',
             b'known',
             b'lookup',
             b'pushkey',
         ):
             return True
 
         # Other concepts.
-        if name in b'bundle2':
+        if name in (b'bundle2',):
             return True
 
         # Alias command-* to presence of command of that name.
         if name.startswith(b'command-'):
             return name[len(b'command-') :] in self.apidescriptor[b'commands']
 
         return False
 
     def requirecap(self, name, purpose):
         if self.capable(name):
             return
 
         raise error.CapabilityError(
             _(
                 b'cannot %s; client or remote repository does not support the '
                 b'\'%s\' capability'
             )
             % (purpose, name)
         )
 
     # End of ipeercapabilities.
 
     def _call(self, name, **args):
         with self.commandexecutor() as e:
             return e.callcommand(name, args).result()
 
     def commandexecutor(self):
         return httpv2executor(
             self.ui,
             self._opener,
             self._requestbuilder,
             self._apiurl,
             self.apidescriptor,
             self._redirect,
         )
 
 
 # Registry of API service names to metadata about peers that handle it.
 #
 # The following keys are meaningful:
 #
 # init
 #    Callable receiving (ui, repourl, servicepath, opener, requestbuilder,
 #                        apidescriptor) to create a peer.
 #
 # priority
 #    Integer priority for the service. If we could choose from multiple
 #    services, we choose the one with the highest priority.
 API_PEERS = {
     wireprototypes.HTTP_WIREPROTO_V2: {
         b'init': httpv2peer,
         b'priority': 50,
     },
 }
 
 
 def performhandshake(ui, url, opener, requestbuilder):
     # The handshake is a request to the capabilities command.
 
     caps = None
 
     def capable(x):
         raise error.ProgrammingError(b'should not be called')
 
     args = {}
 
     # The client advertises support for newer protocols by adding an
     # X-HgUpgrade-* header with a list of supported APIs and an
     # X-HgProto-* header advertising which serializing formats it supports.
     # We only support the HTTP version 2 transport and CBOR responses for
     # now.
     advertisev2 = ui.configbool(b'experimental', b'httppeer.advertise-v2')
 
     if advertisev2:
         args[b'headers'] = {
             'X-HgProto-1': 'cbor',
         }
 
         args[b'headers'].update(
             encodevalueinheaders(
                 b' '.join(sorted(API_PEERS)),
                 b'X-HgUpgrade',
                 # We don't know the header limit this early.
                 # So make it small.
                 1024,
             )
         )
 
     req, requrl, qs = makev1commandrequest(
         ui, requestbuilder, caps, capable, url, b'capabilities', args
     )
     resp = sendrequest(ui, opener, req)
 
     # The server may redirect us to the repo root, stripping the
     # ?cmd=capabilities query string from the URL. The server would likely
     # return HTML in this case and ``parsev1commandresponse()`` would raise.
     # We catch this special case and re-issue the capabilities request against
     # the new URL.
     #
     # We should ideally not do this, as a redirect that drops the query
     # string from the URL is arguably a server bug. (Garbage in, garbage out).
     # However,  Mercurial clients for several years appeared to handle this
     # issue without behavior degradation. And according to issue 5860, it may
     # be a longstanding bug in some server implementations. So we allow a
     # redirect that drops the query string to "just work."
     try:
         respurl, ct, resp = parsev1commandresponse(
             ui, url, requrl, qs, resp, compressible=False, allowcbor=advertisev2
         )
     except RedirectedRepoError as e:
         req, requrl, qs = makev1commandrequest(
             ui, requestbuilder, caps, capable, e.respurl, b'capabilities', args
         )
         resp = sendrequest(ui, opener, req)
         respurl, ct, resp = parsev1commandresponse(
             ui, url, requrl, qs, resp, compressible=False, allowcbor=advertisev2
         )
 
     try:
         rawdata = resp.read()
     finally:
         resp.close()
 
     if not ct.startswith(b'application/mercurial-'):
         raise error.ProgrammingError(b'unexpected content-type: %s' % ct)
 
     if advertisev2:
         if ct == b'application/mercurial-cbor':
             try:
                 info = cborutil.decodeall(rawdata)[0]
             except cborutil.CBORDecodeError:
                 raise error.Abort(
                     _(b'error decoding CBOR from remote server'),
                     hint=_(
                         b'try again and consider contacting '
                         b'the server operator'
                     ),
                 )
 
         # We got a legacy response. That's fine.
         elif ct in (b'application/mercurial-0.1', b'application/mercurial-0.2'):
             info = {b'v1capabilities': set(rawdata.split())}
 
         else:
             raise error.RepoError(
                 _(b'unexpected response type from server: %s') % ct
             )
     else:
         info = {b'v1capabilities': set(rawdata.split())}
 
     return respurl, info
 
 
 def makepeer(ui, path, opener=None, requestbuilder=urlreq.request):
     """Construct an appropriate HTTP peer instance.
 
     ``opener`` is an ``url.opener`` that should be used to establish
     connections, perform HTTP requests.
 
     ``requestbuilder`` is the type used for constructing HTTP requests.
     It exists as an argument so extensions can override the default.
     """
     u = util.url(path)
     if u.query or u.fragment:
         raise error.Abort(
             _(b'unsupported URL component: "%s"') % (u.query or u.fragment)
         )
 
     # urllib cannot handle URLs with embedded user or passwd.
     url, authinfo = u.authinfo()
     ui.debug(b'using %s\n' % url)
 
     opener = opener or urlmod.opener(ui, authinfo)
 
     respurl, info = performhandshake(ui, url, opener, requestbuilder)
 
     # Given the intersection of APIs that both we and the server support,
     # sort by their advertised priority and pick the first one.
     #
     # TODO consider making this request-based and interface driven. For
     # example, the caller could say "I want a peer that does X." It's quite
     # possible that not all peers would do that. Since we know the service
     # capabilities, we could filter out services not meeting the
     # requirements. Possibly by consulting the interfaces defined by the
     # peer type.
     apipeerchoices = set(info.get(b'apis', {}).keys()) & set(API_PEERS.keys())
 
     preferredchoices = sorted(
         apipeerchoices, key=lambda x: API_PEERS[x][b'priority'], reverse=True
     )
 
     for service in preferredchoices:
         apipath = b'%s/%s' % (info[b'apibase'].rstrip(b'/'), service)
 
         return API_PEERS[service][b'init'](
             ui, respurl, apipath, opener, requestbuilder, info[b'apis'][service]
         )
 
     # Failed to construct an API peer. Fall back to legacy.
     return httppeer(
         ui, path, respurl, opener, requestbuilder, info[b'v1capabilities']
     )
 
 
 def instance(ui, path, create, intents=None, createopts=None):
     if create:
         raise error.Abort(_(b'cannot create new http repository'))
     try:
         if path.startswith(b'https:') and not urlmod.has_https:
             raise error.Abort(
                 _(b'Python support for SSL and HTTPS is not installed')
             )
 
         inst = makepeer(ui, path)
 
         return inst
     except error.RepoError as httpexception:
         try:
             r = statichttprepo.instance(ui, b"static-" + path, create)
             ui.note(_(b'(falling back to static-http)\n'))
             return r
         except error.RepoError:
             raise httpexception  # use the original http RepoError instead