statichttprepo: explicitly convert error message to str (issue6247)

For Python 2.7, the implicit conversion of the HTTPError instance to
str was good enough. For Python 3.x, this fails later when hitting the
str to bytes conversion logic.

Differential Revision: https://phab.mercurial-scm.org/D9661

mercurial/statichttprepo.py

@@ -1,255 +1,258
 # statichttprepo.py - simple http repository class for mercurial
 #
 # This provides read-only repo access to repositories exported via static http
 #
 # Copyright 2005-2007 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 errno
 
 from .i18n import _
 from . import (
     branchmap,
     changelog,
     error,
     localrepo,
     manifest,
     namespaces,
     pathutil,
     pycompat,
     url,
     util,
     vfs as vfsmod,
 )
 
 urlerr = util.urlerr
 urlreq = util.urlreq
 
 
 class httprangereader(object):
     def __init__(self, url, opener):
         # we assume opener has HTTPRangeHandler
         self.url = url
         self.pos = 0
         self.opener = opener
         self.name = url
 
     def __enter__(self):
         return self
 
     def __exit__(self, exc_type, exc_value, traceback):
         self.close()
 
     def seek(self, pos):
         self.pos = pos
 
     def read(self, bytes=None):
         req = urlreq.request(pycompat.strurl(self.url))
         end = b''
         if bytes:
             end = self.pos + bytes - 1
         if self.pos or end:
             req.add_header('Range', 'bytes=%d-%s' % (self.pos, end))
 
         try:
             f = self.opener.open(req)
             data = f.read()
             code = f.code
         except urlerr.httperror as inst:
             num = inst.code == 404 and errno.ENOENT or None
-            raise IOError(num, inst)
+            # Explicitly convert the exception to str as Py3 will try
+            # convert it to local encoding and with as the HTTPResponse
+            # instance doesn't support encode.
+            raise IOError(num, str(inst))
         except urlerr.urlerror as inst:
             raise IOError(None, inst.reason)
 
         if code == 200:
             # HTTPRangeHandler does nothing if remote does not support
             # Range headers and returns the full entity. Let's slice it.
             if bytes:
                 data = data[self.pos : self.pos + bytes]
             else:
                 data = data[self.pos :]
         elif bytes:
             data = data[:bytes]
         self.pos += len(data)
         return data
 
     def readlines(self):
         return self.read().splitlines(True)
 
     def __iter__(self):
         return iter(self.readlines())
 
     def close(self):
         pass
 
 
 # _RangeError and _HTTPRangeHandler were originally in byterange.py,
 # which was itself extracted from urlgrabber. See the last version of
 # byterange.py from history if you need more information.
 class _RangeError(IOError):
     """Error raised when an unsatisfiable range is requested."""
 
 
 class _HTTPRangeHandler(urlreq.basehandler):
     """Handler that enables HTTP Range headers.
 
     This was extremely simple. The Range header is a HTTP feature to
     begin with so all this class does is tell urllib2 that the
     "206 Partial Content" response from the HTTP server is what we
     expected.
     """
 
     def http_error_206(self, req, fp, code, msg, hdrs):
         # 206 Partial Content Response
         r = urlreq.addinfourl(fp, hdrs, req.get_full_url())
         r.code = code
         r.msg = msg
         return r
 
     def http_error_416(self, req, fp, code, msg, hdrs):
         # HTTP's Range Not Satisfiable error
         raise _RangeError(b'Requested Range Not Satisfiable')
 
 
 def build_opener(ui, authinfo):
     # urllib cannot handle URLs with embedded user or passwd
     urlopener = url.opener(ui, authinfo)
     urlopener.add_handler(_HTTPRangeHandler())
 
     class statichttpvfs(vfsmod.abstractvfs):
         def __init__(self, base):
             self.base = base
             self.options = {}
 
         def __call__(self, path, mode=b'r', *args, **kw):
             if mode not in (b'r', b'rb'):
                 raise IOError(b'Permission denied')
             f = b"/".join((self.base, urlreq.quote(path)))
             return httprangereader(f, urlopener)
 
         def join(self, path):
             if path:
                 return pathutil.join(self.base, path)
             else:
                 return self.base
 
     return statichttpvfs
 
 
 class statichttppeer(localrepo.localpeer):
     def local(self):
         return None
 
     def canpush(self):
         return False
 
 
 class statichttprepository(
     localrepo.localrepository, localrepo.revlogfilestorage
 ):
     supported = localrepo.localrepository._basesupported
 
     def __init__(self, ui, path):
         self._url = path
         self.ui = ui
 
         self.root = path
         u = util.url(path.rstrip(b'/') + b"/.hg")
         self.path, authinfo = u.authinfo()
 
         vfsclass = build_opener(ui, authinfo)
         self.vfs = vfsclass(self.path)
         self.cachevfs = vfsclass(self.vfs.join(b'cache'))
         self._phasedefaults = []
 
         self.names = namespaces.namespaces()
         self.filtername = None
         self._extrafilterid = None
 
         try:
             requirements = set(self.vfs.read(b'requires').splitlines())
         except IOError as inst:
             if inst.errno != errno.ENOENT:
                 raise
             requirements = set()
 
             # check if it is a non-empty old-style repository
             try:
                 fp = self.vfs(b"00changelog.i")
                 fp.read(1)
                 fp.close()
             except IOError as inst:
                 if inst.errno != errno.ENOENT:
                     raise
                 # we do not care about empty old-style repositories here
                 msg = _(b"'%s' does not appear to be an hg repository") % path
                 raise error.RepoError(msg)
 
         supportedrequirements = localrepo.gathersupportedrequirements(ui)
         localrepo.ensurerequirementsrecognized(
             requirements, supportedrequirements
         )
         localrepo.ensurerequirementscompatible(ui, requirements)
 
         # setup store
         self.store = localrepo.makestore(requirements, self.path, vfsclass)
         self.spath = self.store.path
         self.svfs = self.store.opener
         self.sjoin = self.store.join
         self._filecache = {}
         self.requirements = requirements
 
         rootmanifest = manifest.manifestrevlog(self.svfs)
         self.manifestlog = manifest.manifestlog(
             self.svfs, self, rootmanifest, self.narrowmatch()
         )
         self.changelog = changelog.changelog(self.svfs)
         self._tags = None
         self.nodetagscache = None
         self._branchcaches = branchmap.BranchMapCache()
         self._revbranchcache = None
         self.encodepats = None
         self.decodepats = None
         self._transref = None
 
     def _restrictcapabilities(self, caps):
         caps = super(statichttprepository, self)._restrictcapabilities(caps)
         return caps.difference([b"pushkey"])
 
     def url(self):
         return self._url
 
     def local(self):
         return False
 
     def peer(self):
         return statichttppeer(self)
 
     def wlock(self, wait=True):
         raise error.LockUnavailable(
             0,
             _(b'lock not available'),
             b'lock',
             _(b'cannot lock static-http repository'),
         )
 
     def lock(self, wait=True):
         raise error.LockUnavailable(
             0,
             _(b'lock not available'),
             b'lock',
             _(b'cannot lock static-http repository'),
         )
 
     def _writecaches(self):
         pass  # statichttprepository are read only
 
 
 def instance(ui, path, create, intents=None, createopts=None):
     if create:
         raise error.Abort(_(b'cannot create new static-http repository'))
     return statichttprepository(ui, path[7:])