httprepo: remove is-comparison with string literal

An identity check between a variable and a string literal was added to
the pushkey implementation in 6bd9778ae749. While CPython will
normally intern strings and thus make the test safe, value identity is
what should be used here.

mercurial/httprepo.py

@@ -1,203 +1,203 b''
 # httprepo.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 node import nullid
 from i18n import _
 import changegroup, statichttprepo, error, url, util, wireproto
 import os, urllib, urllib2, urlparse, zlib, httplib
 import errno, socket
 
 def zgenerator(f):
     zd = zlib.decompressobj()
     try:
         for chunk in util.filechunkiter(f):
             while chunk:
                 yield zd.decompress(chunk, 2**18)
                 chunk = zd.unconsumed_tail
     except httplib.HTTPException:
         raise IOError(None, _('connection ended unexpectedly'))
     yield zd.flush()
 
 class httprepository(wireproto.wirerepository):
     def __init__(self, ui, path):
         self.path = path
         self.caps = None
         self.handler = None
         scheme, netloc, urlpath, query, frag = urlparse.urlsplit(path)
         if query or frag:
             raise util.Abort(_('unsupported URL component: "%s"') %
                              (query or frag))
 
         # urllib cannot handle URLs with embedded user or passwd
         self._url, authinfo = url.getauthinfo(path)
 
         self.ui = ui
         self.ui.debug('using %s\n' % self._url)
 
         self.urlopener = url.opener(ui, authinfo)
 
     def __del__(self):
         for h in self.urlopener.handlers:
             h.close()
             if hasattr(h, "close_all"):
                 h.close_all()
 
     def url(self):
         return self.path
 
     # look up capabilities only when needed
 
     def get_caps(self):
         if self.caps is None:
             try:
                 self.caps = set(self._call('capabilities').split())
             except error.RepoError:
                 self.caps = set()
             self.ui.debug('capabilities: %s\n' %
                           (' '.join(self.caps or ['none'])))
         return self.caps
 
     capabilities = property(get_caps)
 
     def lock(self):
         raise util.Abort(_('operation not supported over http'))
 
     def _callstream(self, cmd, **args):
-        if cmd is 'pushkey':
+        if cmd == 'pushkey':
             args['data'] = ''
         data = args.pop('data', None)
         headers = args.pop('headers', {})
         self.ui.debug("sending %s command\n" % cmd)
         q = {"cmd": cmd}
         q.update(args)
         qs = '?%s' % urllib.urlencode(q)
         cu = "%s%s" % (self._url, qs)
         req = urllib2.Request(cu, data, headers)
         if data is not None:
             # len(data) is broken if data doesn't fit into Py_ssize_t
             # add the header ourself to avoid OverflowError
             size = data.__len__()
             self.ui.debug("sending %s bytes\n" % size)
             req.add_unredirected_header('Content-Length', '%d' % size)
         try:
             resp = self.urlopener.open(req)
         except urllib2.HTTPError, inst:
             if inst.code == 401:
                 raise util.Abort(_('authorization failed'))
             raise
         except httplib.HTTPException, inst:
             self.ui.debug('http error while sending %s command\n' % cmd)
             self.ui.traceback()
             raise IOError(None, inst)
         except IndexError:
             # this only happens with Python 2.3, later versions raise URLError
             raise util.Abort(_('http error, possibly caused by proxy setting'))
         # record the url we got redirected to
         resp_url = resp.geturl()
         if resp_url.endswith(qs):
             resp_url = resp_url[:-len(qs)]
         if self._url.rstrip('/') != resp_url.rstrip('/'):
             self.ui.status(_('real URL is %s\n') % resp_url)
         self._url = resp_url
         try:
             proto = resp.getheader('content-type')
         except AttributeError:
             proto = resp.headers['content-type']
 
         safeurl = url.hidepassword(self._url)
         # accept old "text/plain" and "application/hg-changegroup" for now
         if not (proto.startswith('application/mercurial-') or
                 proto.startswith('text/plain') or
                 proto.startswith('application/hg-changegroup')):
             self.ui.debug("requested URL: '%s'\n" % url.hidepassword(cu))
             raise error.RepoError(
                 _("'%s' does not appear to be an hg repository:\n"
                   "---%%<--- (%s)\n%s\n---%%<---\n")
                 % (safeurl, proto, resp.read()))
 
         if proto.startswith('application/mercurial-'):
             try:
                 version = proto.split('-', 1)[1]
                 version_info = tuple([int(n) for n in version.split('.')])
             except ValueError:
                 raise error.RepoError(_("'%s' sent a broken Content-Type "
                                         "header (%s)") % (safeurl, proto))
             if version_info > (0, 1):
                 raise error.RepoError(_("'%s' uses newer protocol %s") %
                                       (safeurl, version))
 
         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.
 
         type = ""
         types = self.capable('unbundle')
         # servers older than d1b16a746db6 will send 'unbundle' as a
         # boolean capability
         try:
             types = types.split(',')
         except AttributeError:
             types = [""]
         if types:
             for x in types:
                 if x in changegroup.bundletypes:
                     type = x
                     break
 
         tempname = changegroup.writebundle(cg, None, type)
         fp = url.httpsendfile(tempname, "rb")
         headers = {'Content-Type': 'application/mercurial-0.1'}
 
         try:
             try:
                 r = self._call(cmd, data=fp, headers=headers, **args)
                 return r.split('\n', 1)
             except socket.error, err:
                 if err.args[0] in (errno.ECONNRESET, errno.EPIPE):
                     raise util.Abort(_('push failed: %s') % err.args[1])
                 raise util.Abort(err.args[1])
         finally:
             fp.close()
             os.unlink(tempname)
 
     def _abort(self, exception):
         raise exception
 
     def _decompress(self, stream):
         return util.chunkbuffer(zgenerator(stream))
 
 class httpsrepository(httprepository):
     def __init__(self, ui, path):
         if not url.has_https:
             raise util.Abort(_('Python support for SSL and HTTPS '
                                'is not installed'))
         httprepository.__init__(self, ui, path)
 
 def instance(ui, path, create):
     if create:
         raise util.Abort(_('cannot create new http repository'))
     try:
         if path.startswith('https:'):
             inst = httpsrepository(ui, path)
         else:
             inst = httprepository(ui, path)
         inst.between([(nullid, nullid)])
         return inst
     except error.RepoError:
         ui.note('(falling back to static-http)\n')
         return statichttprepo.instance(ui, "static-" + path, create)