clone: explicitly detect the need to fetch a peer

Instead of having `peer()` method on all `peer()` for this usecase, we could
simply handle it explicitly.

mercurial/hg.py

@@ -1,1664 +1,1669 b''
 # hg.py - repository classes for mercurial
 #
 # Copyright 2005-2007 Olivia 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.
 
 
 import os
 import posixpath
 import shutil
 import stat
 import weakref
 
 from .i18n import _
 from .node import (
     hex,
     sha1nodeconstants,
     short,
 )
 from .pycompat import getattr
 
 from . import (
     bookmarks,
     bundlerepo,
     cmdutil,
     destutil,
     discovery,
     error,
     exchange,
     extensions,
     graphmod,
     httppeer,
     localrepo,
     lock,
     logcmdutil,
     logexchange,
     merge as mergemod,
     mergestate as mergestatemod,
     narrowspec,
     phases,
     requirements,
     scmutil,
     sshpeer,
     statichttprepo,
     ui as uimod,
     unionrepo,
     url,
     util,
     verify as verifymod,
     vfs as vfsmod,
 )
 from .interfaces import repository as repositorymod
 from .utils import (
     hashutil,
     stringutil,
     urlutil,
 )
 
 
 release = lock.release
 
 # shared features
 sharedbookmarks = b'bookmarks'
 
 
 def addbranchrevs(lrepo, other, branches, revs):
     if util.safehasattr(other, 'peer'):
         # a courtesy to callers using a localrepo for other
         peer = other.peer()
     else:
         peer = other
     hashbranch, branches = branches
     if not hashbranch and not branches:
         x = revs or None
         if revs:
             y = revs[0]
         else:
             y = None
         return x, y
     if revs:
         revs = list(revs)
     else:
         revs = []
 
     if not peer.capable(b'branchmap'):
         if branches:
             raise error.Abort(_(b"remote branch lookup not supported"))
         revs.append(hashbranch)
         return revs, revs[0]
 
     with peer.commandexecutor() as e:
         branchmap = e.callcommand(b'branchmap', {}).result()
 
     def primary(branch):
         if branch == b'.':
             if not lrepo:
                 raise error.Abort(_(b"dirstate branch not accessible"))
             branch = lrepo.dirstate.branch()
         if branch in branchmap:
             revs.extend(hex(r) for r in reversed(branchmap[branch]))
             return True
         else:
             return False
 
     for branch in branches:
         if not primary(branch):
             raise error.RepoLookupError(_(b"unknown branch '%s'") % branch)
     if hashbranch:
         if not primary(hashbranch):
             revs.append(hashbranch)
     return revs, revs[0]
 
 
 def _isfile(path):
     try:
         # we use os.stat() directly here instead of os.path.isfile()
         # because the latter started returning `False` on invalid path
         # exceptions starting in 3.8 and we care about handling
         # invalid paths specially here.
         st = os.stat(path)
     except ValueError as e:
         msg = stringutil.forcebytestr(e)
         raise error.Abort(_(b'invalid path %s: %s') % (path, msg))
     except OSError:
         return False
     else:
         return stat.S_ISREG(st.st_mode)
 
 
 class LocalFactory:
     """thin wrapper to dispatch between localrepo and bundle repo"""
 
     @staticmethod
     def islocal(path: bytes) -> bool:
         path = util.expandpath(urlutil.urllocalpath(path))
         return not _isfile(path)
 
     @staticmethod
     def instance(ui, path, *args, **kwargs):
         path = util.expandpath(urlutil.urllocalpath(path))
         if _isfile(path):
             cls = bundlerepo
         else:
             cls = localrepo
         return cls.instance(ui, path, *args, **kwargs)
 
 
 repo_schemes = {
     b'bundle': bundlerepo,
     b'union': unionrepo,
     b'file': LocalFactory,
 }
 
 peer_schemes = {
     b'http': httppeer,
     b'https': httppeer,
     b'ssh': sshpeer,
     b'static-http': statichttprepo,
 }
 
 
 def _peerlookup(path):
     u = urlutil.url(path)
     scheme = u.scheme or b'file'
     if scheme in peer_schemes:
         return peer_schemes[scheme]
     if scheme in repo_schemes:
         return repo_schemes[scheme]
     return LocalFactory
 
 
 def islocal(repo):
     '''return true if repo (or path pointing to repo) is local'''
     if isinstance(repo, bytes):
         cls = _peerlookup(repo)
         cls.instance  # make sure we load the module
         if util.safehasattr(cls, 'islocal'):
             return cls.islocal(repo)  # pytype: disable=module-attr
         return False
     repo.ui.deprecwarn(b"use obj.local() instead of islocal(obj)", b"6.4")
     return repo.local()
 
 
 def openpath(ui, path, sendaccept=True):
     '''open path with open if local, url.open if remote'''
     pathurl = urlutil.url(path, parsequery=False, parsefragment=False)
     if pathurl.islocal():
         return util.posixfile(pathurl.localpath(), b'rb')
     else:
         return url.open(ui, path, sendaccept=sendaccept)
 
 
 # a list of (ui, repo) functions called for wire peer initialization
 wirepeersetupfuncs = []
 
 
 def _setup_repo_or_peer(ui, obj, presetupfuncs=None):
     ui = getattr(obj, "ui", ui)
     for f in presetupfuncs or []:
         f(ui, obj)
     ui.log(b'extension', b'- executing reposetup hooks\n')
     with util.timedcm('all reposetup') as allreposetupstats:
         for name, module in extensions.extensions(ui):
             ui.log(b'extension', b'  - running reposetup for %s\n', name)
             hook = getattr(module, 'reposetup', None)
             if hook:
                 with util.timedcm('reposetup %r', name) as stats:
                     hook(ui, obj)
                 msg = b'  > reposetup for %s took %s\n'
                 ui.log(b'extension', msg, name, stats)
     ui.log(b'extension', b'> all reposetup took %s\n', allreposetupstats)
     if not obj.local():
         for f in wirepeersetupfuncs:
             f(ui, obj)
 
 
 def repository(
     ui,
     path=b'',
     create=False,
     presetupfuncs=None,
     intents=None,
     createopts=None,
 ):
     """return a repository object for the specified path"""
     scheme = urlutil.url(path).scheme
     if scheme is None:
         scheme = b'file'
     cls = repo_schemes.get(scheme)
     if cls is None:
         if scheme in peer_schemes:
             raise error.Abort(_(b"repository '%s' is not local") % path)
         cls = LocalFactory
     repo = cls.instance(
         ui,
         path,
         create,
         intents=intents,
         createopts=createopts,
     )
     _setup_repo_or_peer(ui, repo, presetupfuncs=presetupfuncs)
     return repo.filtered(b'visible')
 
 
 def peer(uiorrepo, opts, path, create=False, intents=None, createopts=None):
     '''return a repository peer for the specified path'''
     rui = remoteui(uiorrepo, opts)
     if util.safehasattr(path, 'url'):
         # this is a urlutil.path object
         scheme = path.url.scheme  # pytype: disable=attribute-error
         # XXX for now we don't do anything more than that
         path = path.loc  # pytype: disable=attribute-error
     else:
         scheme = urlutil.url(path).scheme
     if scheme in peer_schemes:
         cls = peer_schemes[scheme]
         peer = cls.instance(
             rui,
             path,
             create,
             intents=intents,
             createopts=createopts,
         )
         _setup_repo_or_peer(rui, peer)
     else:
         # this is a repository
         repo = repository(
             rui,
             path,
             create,
             intents=intents,
             createopts=createopts,
         )
         peer = repo.peer()
     return peer
 
 
 def defaultdest(source):
     """return default destination of clone if none is given
 
     >>> defaultdest(b'foo')
     'foo'
     >>> defaultdest(b'/foo/bar')
     'bar'
     >>> defaultdest(b'/')
     ''
     >>> defaultdest(b'')
     ''
     >>> defaultdest(b'http://example.org/')
     ''
     >>> defaultdest(b'http://example.org/foo/')
     'foo'
     """
     path = urlutil.url(source).path
     if not path:
         return b''
     return os.path.basename(os.path.normpath(path))
 
 
 def sharedreposource(repo):
     """Returns repository object for source repository of a shared repo.
 
     If repo is not a shared repository, returns None.
     """
     if repo.sharedpath == repo.path:
         return None
 
     if util.safehasattr(repo, b'srcrepo') and repo.srcrepo:
         return repo.srcrepo
 
     # the sharedpath always ends in the .hg; we want the path to the repo
     source = repo.vfs.split(repo.sharedpath)[0]
     srcurl, branches = urlutil.parseurl(source)
     srcrepo = repository(repo.ui, srcurl)
     repo.srcrepo = srcrepo
     return srcrepo
 
 
 def share(
     ui,
     source,
     dest=None,
     update=True,
     bookmarks=True,
     defaultpath=None,
     relative=False,
 ):
     '''create a shared repository'''
 
     not_local_msg = _(b'can only share local repositories')
     if util.safehasattr(source, 'local'):
         if source.local() is None:
             raise error.Abort(not_local_msg)
     elif not islocal(source):
         # XXX why are we getting bytes here ?
         raise error.Abort(not_local_msg)
 
     if not dest:
         dest = defaultdest(source)
     else:
         dest = urlutil.get_clone_path_obj(ui, dest).loc
 
     if isinstance(source, bytes):
         source_path = urlutil.get_clone_path_obj(ui, source)
         srcrepo = repository(ui, source_path.loc)
         branches = (source_path.branch, [])
         rev, checkout = addbranchrevs(srcrepo, srcrepo, branches, None)
     else:
         srcrepo = source.local()
         checkout = None
 
     shareditems = set()
     if bookmarks:
         shareditems.add(sharedbookmarks)
 
     r = repository(
         ui,
         dest,
         create=True,
         createopts={
             b'sharedrepo': srcrepo,
             b'sharedrelative': relative,
             b'shareditems': shareditems,
         },
     )
 
     postshare(srcrepo, r, defaultpath=defaultpath)
     r = repository(ui, dest)
     _postshareupdate(r, update, checkout=checkout)
     return r
 
 
 def _prependsourcehgrc(repo):
     """copies the source repo config and prepend it in current repo .hg/hgrc
     on unshare. This is only done if the share was perfomed using share safe
     method where we share config of source in shares"""
     srcvfs = vfsmod.vfs(repo.sharedpath)
     dstvfs = vfsmod.vfs(repo.path)
 
     if not srcvfs.exists(b'hgrc'):
         return
 
     currentconfig = b''
     if dstvfs.exists(b'hgrc'):
         currentconfig = dstvfs.read(b'hgrc')
 
     with dstvfs(b'hgrc', b'wb') as fp:
         sourceconfig = srcvfs.read(b'hgrc')
         fp.write(b"# Config copied from shared source\n")
         fp.write(sourceconfig)
         fp.write(b'\n')
         fp.write(currentconfig)
 
 
 def unshare(ui, repo):
     """convert a shared repository to a normal one
 
     Copy the store data to the repo and remove the sharedpath data.
 
     Returns a new repository object representing the unshared repository.
 
     The passed repository object is not usable after this function is
     called.
     """
 
     with repo.lock():
         # we use locks here because if we race with commit, we
         # can end up with extra data in the cloned revlogs that's
         # not pointed to by changesets, thus causing verify to
         # fail
         destlock = copystore(ui, repo, repo.path)
         with destlock or util.nullcontextmanager():
             if requirements.SHARESAFE_REQUIREMENT in repo.requirements:
                 # we were sharing .hg/hgrc of the share source with the current
                 # repo. We need to copy that while unsharing otherwise it can
                 # disable hooks and other checks
                 _prependsourcehgrc(repo)
 
             sharefile = repo.vfs.join(b'sharedpath')
             util.rename(sharefile, sharefile + b'.old')
 
             repo.requirements.discard(requirements.SHARED_REQUIREMENT)
             repo.requirements.discard(requirements.RELATIVE_SHARED_REQUIREMENT)
             scmutil.writereporequirements(repo)
 
     # Removing share changes some fundamental properties of the repo instance.
     # So we instantiate a new repo object and operate on it rather than
     # try to keep the existing repo usable.
     newrepo = repository(repo.baseui, repo.root, create=False)
 
     # TODO: figure out how to access subrepos that exist, but were previously
     #       removed from .hgsub
     c = newrepo[b'.']
     subs = c.substate
     for s in sorted(subs):
         c.sub(s).unshare()
 
     localrepo.poisonrepository(repo)
 
     return newrepo
 
 
 def postshare(sourcerepo, destrepo, defaultpath=None):
     """Called after a new shared repo is created.
 
     The new repo only has a requirements file and pointer to the source.
     This function configures additional shared data.
 
     Extensions can wrap this function and write additional entries to
     destrepo/.hg/shared to indicate additional pieces of data to be shared.
     """
     default = defaultpath or sourcerepo.ui.config(b'paths', b'default')
     if default:
         template = b'[paths]\ndefault = %s\n'
         destrepo.vfs.write(b'hgrc', util.tonativeeol(template % default))
     if requirements.NARROW_REQUIREMENT in sourcerepo.requirements:
         with destrepo.wlock():
             narrowspec.copytoworkingcopy(destrepo)
 
 
 def _postshareupdate(repo, update, checkout=None):
     """Maybe perform a working directory update after a shared repo is created.
 
     ``update`` can be a boolean or a revision to update to.
     """
     if not update:
         return
 
     repo.ui.status(_(b"updating working directory\n"))
     if update is not True:
         checkout = update
     for test in (checkout, b'default', b'tip'):
         if test is None:
             continue
         try:
             uprev = repo.lookup(test)
             break
         except error.RepoLookupError:
             continue
     _update(repo, uprev)
 
 
 def copystore(ui, srcrepo, destpath):
     """copy files from store of srcrepo in destpath
 
     returns destlock
     """
     destlock = None
     try:
         hardlink = None
         topic = _(b'linking') if hardlink else _(b'copying')
         with ui.makeprogress(topic, unit=_(b'files')) as progress:
             num = 0
             srcpublishing = srcrepo.publishing()
             srcvfs = vfsmod.vfs(srcrepo.sharedpath)
             dstvfs = vfsmod.vfs(destpath)
             for f in srcrepo.store.copylist():
                 if srcpublishing and f.endswith(b'phaseroots'):
                     continue
                 dstbase = os.path.dirname(f)
                 if dstbase and not dstvfs.exists(dstbase):
                     dstvfs.mkdir(dstbase)
                 if srcvfs.exists(f):
                     if f.endswith(b'data'):
                         # 'dstbase' may be empty (e.g. revlog format 0)
                         lockfile = os.path.join(dstbase, b"lock")
                         # lock to avoid premature writing to the target
                         destlock = lock.lock(dstvfs, lockfile)
                     hardlink, n = util.copyfiles(
                         srcvfs.join(f), dstvfs.join(f), hardlink, progress
                     )
                     num += n
             if hardlink:
                 ui.debug(b"linked %d files\n" % num)
             else:
                 ui.debug(b"copied %d files\n" % num)
         return destlock
     except:  # re-raises
         release(destlock)
         raise
 
 
 def clonewithshare(
     ui,
     peeropts,
     sharepath,
     source,
     srcpeer,
     dest,
     pull=False,
     rev=None,
     update=True,
     stream=False,
 ):
     """Perform a clone using a shared repo.
 
     The store for the repository will be located at <sharepath>/.hg. The
     specified revisions will be cloned or pulled from "source". A shared repo
     will be created at "dest" and a working copy will be created if "update" is
     True.
     """
     revs = None
     if rev:
         if not srcpeer.capable(b'lookup'):
             raise error.Abort(
                 _(
                     b"src repository does not support "
                     b"revision lookup and so doesn't "
                     b"support clone by revision"
                 )
             )
 
         # TODO this is batchable.
         remoterevs = []
         for r in rev:
             with srcpeer.commandexecutor() as e:
                 remoterevs.append(
                     e.callcommand(
                         b'lookup',
                         {
                             b'key': r,
                         },
                     ).result()
                 )
         revs = remoterevs
 
     # Obtain a lock before checking for or cloning the pooled repo otherwise
     # 2 clients may race creating or populating it.
     pooldir = os.path.dirname(sharepath)
     # lock class requires the directory to exist.
     try:
         util.makedir(pooldir, False)
     except FileExistsError:
         pass
 
     poolvfs = vfsmod.vfs(pooldir)
     basename = os.path.basename(sharepath)
 
     with lock.lock(poolvfs, b'%s.lock' % basename):
         if os.path.exists(sharepath):
             ui.status(
                 _(b'(sharing from existing pooled repository %s)\n') % basename
             )
         else:
             ui.status(
                 _(b'(sharing from new pooled repository %s)\n') % basename
             )
             # Always use pull mode because hardlinks in share mode don't work
             # well. Never update because working copies aren't necessary in
             # share mode.
             clone(
                 ui,
                 peeropts,
                 source,
                 dest=sharepath,
                 pull=True,
                 revs=rev,
                 update=False,
                 stream=stream,
             )
 
     # Resolve the value to put in [paths] section for the source.
     if islocal(source):
         defaultpath = util.abspath(urlutil.urllocalpath(source))
     else:
         defaultpath = source
 
     sharerepo = repository(ui, path=sharepath)
     destrepo = share(
         ui,
         sharerepo,
         dest=dest,
         update=False,
         bookmarks=False,
         defaultpath=defaultpath,
     )
 
     # We need to perform a pull against the dest repo to fetch bookmarks
     # and other non-store data that isn't shared by default. In the case of
     # non-existing shared repo, this means we pull from the remote twice. This
     # is a bit weird. But at the time it was implemented, there wasn't an easy
     # way to pull just non-changegroup data.
     exchange.pull(destrepo, srcpeer, heads=revs)
 
     _postshareupdate(destrepo, update)
 
     return srcpeer, peer(ui, peeropts, dest)
 
 
 # Recomputing caches is often slow on big repos, so copy them.
 def _copycache(srcrepo, dstcachedir, fname):
     """copy a cache from srcrepo to destcachedir (if it exists)"""
     srcfname = srcrepo.cachevfs.join(fname)
     dstfname = os.path.join(dstcachedir, fname)
     if os.path.exists(srcfname):
         if not os.path.exists(dstcachedir):
             os.mkdir(dstcachedir)
         util.copyfile(srcfname, dstfname)
 
 
 def clone(
     ui,
     peeropts,
     source,
     dest=None,
     pull=False,
     revs=None,
     update=True,
     stream=False,
     branch=None,
     shareopts=None,
     storeincludepats=None,
     storeexcludepats=None,
     depth=None,
 ):
     """Make a copy of an existing repository.
 
     Create a copy of an existing repository in a new directory.  The
     source and destination are URLs, as passed to the repository
     function.  Returns a pair of repository peers, the source and
     newly created destination.
 
     The location of the source is added to the new repository's
     .hg/hgrc file, as the default to be used for future pulls and
     pushes.
 
     If an exception is raised, the partly cloned/updated destination
     repository will be deleted.
 
     Arguments:
 
     source: repository object or URL
 
     dest: URL of destination repository to create (defaults to base
     name of source repository)
 
     pull: always pull from source repository, even in local case or if the
     server prefers streaming
 
     stream: stream raw data uncompressed from repository (fast over
     LAN, slow over WAN)
 
     revs: revision to clone up to (implies pull=True)
 
     update: update working directory after clone completes, if
     destination is local repository (True means update to default rev,
     anything else is treated as a revision)
 
     branch: branches to clone
 
     shareopts: dict of options to control auto sharing behavior. The "pool" key
     activates auto sharing mode and defines the directory for stores. The
     "mode" key determines how to construct the directory name of the shared
     repository. "identity" means the name is derived from the node of the first
     changeset in the repository. "remote" means the name is derived from the
     remote's path/URL. Defaults to "identity."
 
     storeincludepats and storeexcludepats: sets of file patterns to include and
     exclude in the repository copy, respectively. If not defined, all files
     will be included (a "full" clone). Otherwise a "narrow" clone containing
     only the requested files will be performed. If ``storeincludepats`` is not
     defined but ``storeexcludepats`` is, ``storeincludepats`` is assumed to be
     ``path:.``. If both are empty sets, no files will be cloned.
     """
 
     if isinstance(source, bytes):
         src_path = urlutil.get_clone_path_obj(ui, source)
         if src_path is None:
             srcpeer = peer(ui, peeropts, b'')
             origsource = source = b''
             branches = (None, branch or [])
         else:
             srcpeer = peer(ui, peeropts, src_path)
             origsource = src_path.rawloc
             branches = (src_path.branch, branch or [])
             source = src_path.loc
     else:
+        if util.safehasattr(source, 'peer'):
+            srcpeer = source.peer()  # in case we were called with a localrepo
+        else:
+            srcpeer = source
+        branches = (None, branch or [])
         # XXX path: simply use the peer `path` object when this become available
         srcpeer = source.peer()  # in case we were called with a localrepo
         branches = (None, branch or [])
         origsource = source = srcpeer.url()
     srclock = destlock = destwlock = cleandir = None
     destpeer = None
     try:
         revs, checkout = addbranchrevs(srcpeer, srcpeer, branches, revs)
 
         if dest is None:
             dest = defaultdest(source)
             if dest:
                 ui.status(_(b"destination directory: %s\n") % dest)
         else:
             dest_path = urlutil.get_clone_path_obj(ui, dest)
             if dest_path is not None:
                 dest = dest_path.rawloc
             else:
                 dest = b''
 
         dest = urlutil.urllocalpath(dest)
         source = urlutil.urllocalpath(source)
 
         if not dest:
             raise error.InputError(_(b"empty destination path is not valid"))
 
         destvfs = vfsmod.vfs(dest, expandpath=True)
         if destvfs.lexists():
             if not destvfs.isdir():
                 raise error.InputError(
                     _(b"destination '%s' already exists") % dest
                 )
             elif destvfs.listdir():
                 raise error.InputError(
                     _(b"destination '%s' is not empty") % dest
                 )
 
         createopts = {}
         narrow = False
 
         if storeincludepats is not None:
             narrowspec.validatepatterns(storeincludepats)
             narrow = True
 
         if storeexcludepats is not None:
             narrowspec.validatepatterns(storeexcludepats)
             narrow = True
 
         if narrow:
             # Include everything by default if only exclusion patterns defined.
             if storeexcludepats and not storeincludepats:
                 storeincludepats = {b'path:.'}
 
             createopts[b'narrowfiles'] = True
 
         if depth:
             createopts[b'shallowfilestore'] = True
 
         if srcpeer.capable(b'lfs-serve'):
             # Repository creation honors the config if it disabled the extension, so
             # we can't just announce that lfs will be enabled.  This check avoids
             # saying that lfs will be enabled, and then saying it's an unknown
             # feature.  The lfs creation option is set in either case so that a
             # requirement is added.  If the extension is explicitly disabled but the
             # requirement is set, the clone aborts early, before transferring any
             # data.
             createopts[b'lfs'] = True
 
             if extensions.disabled_help(b'lfs'):
                 ui.status(
                     _(
                         b'(remote is using large file support (lfs), but it is '
                         b'explicitly disabled in the local configuration)\n'
                     )
                 )
             else:
                 ui.status(
                     _(
                         b'(remote is using large file support (lfs); lfs will '
                         b'be enabled for this repository)\n'
                     )
                 )
 
         shareopts = shareopts or {}
         sharepool = shareopts.get(b'pool')
         sharenamemode = shareopts.get(b'mode')
         if sharepool and islocal(dest):
             sharepath = None
             if sharenamemode == b'identity':
                 # Resolve the name from the initial changeset in the remote
                 # repository. This returns nullid when the remote is empty. It
                 # raises RepoLookupError if revision 0 is filtered or otherwise
                 # not available. If we fail to resolve, sharing is not enabled.
                 try:
                     with srcpeer.commandexecutor() as e:
                         rootnode = e.callcommand(
                             b'lookup',
                             {
                                 b'key': b'0',
                             },
                         ).result()
 
                     if rootnode != sha1nodeconstants.nullid:
                         sharepath = os.path.join(sharepool, hex(rootnode))
                     else:
                         ui.status(
                             _(
                                 b'(not using pooled storage: '
                                 b'remote appears to be empty)\n'
                             )
                         )
                 except error.RepoLookupError:
                     ui.status(
                         _(
                             b'(not using pooled storage: '
                             b'unable to resolve identity of remote)\n'
                         )
                     )
             elif sharenamemode == b'remote':
                 sharepath = os.path.join(
                     sharepool, hex(hashutil.sha1(source).digest())
                 )
             else:
                 raise error.Abort(
                     _(b'unknown share naming mode: %s') % sharenamemode
                 )
 
             # TODO this is a somewhat arbitrary restriction.
             if narrow:
                 ui.status(
                     _(b'(pooled storage not supported for narrow clones)\n')
                 )
                 sharepath = None
 
             if sharepath:
                 return clonewithshare(
                     ui,
                     peeropts,
                     sharepath,
                     source,
                     srcpeer,
                     dest,
                     pull=pull,
                     rev=revs,
                     update=update,
                     stream=stream,
                 )
 
         srcrepo = srcpeer.local()
 
         abspath = origsource
         if islocal(origsource):
             abspath = util.abspath(urlutil.urllocalpath(origsource))
 
         if islocal(dest):
             if os.path.exists(dest):
                 # only clean up directories we create ourselves
                 hgdir = os.path.realpath(os.path.join(dest, b".hg"))
                 cleandir = hgdir
             else:
                 cleandir = dest
 
         copy = False
         if (
             srcrepo
             and srcrepo.cancopy()
             and islocal(dest)
             and not phases.hassecret(srcrepo)
         ):
             copy = not pull and not revs
 
         # TODO this is a somewhat arbitrary restriction.
         if narrow:
             copy = False
 
         if copy:
             try:
                 # we use a lock here because if we race with commit, we
                 # can end up with extra data in the cloned revlogs that's
                 # not pointed to by changesets, thus causing verify to
                 # fail
                 srclock = srcrepo.lock(wait=False)
             except error.LockError:
                 copy = False
 
         if copy:
             srcrepo.hook(b'preoutgoing', throw=True, source=b'clone')
 
             destrootpath = urlutil.urllocalpath(dest)
             dest_reqs = localrepo.clone_requirements(ui, createopts, srcrepo)
             localrepo.createrepository(
                 ui,
                 destrootpath,
                 requirements=dest_reqs,
             )
             destrepo = localrepo.makelocalrepository(ui, destrootpath)
 
             destwlock = destrepo.wlock()
             destlock = destrepo.lock()
             from . import streamclone  # avoid cycle
 
             streamclone.local_copy(srcrepo, destrepo)
 
             # we need to re-init the repo after manually copying the data
             # into it
             destpeer = peer(srcrepo, peeropts, dest)
 
             # make the peer aware that is it already locked
             #
             # important:
             #
             #    We still need to release that lock at the end of the function
             destpeer.local()._lockref = weakref.ref(destlock)
             destpeer.local()._wlockref = weakref.ref(destwlock)
             # dirstate also needs to be copied because `_wlockref` has a reference
             # to it: this dirstate is saved to disk when the wlock is released
             destpeer.local().dirstate = destrepo.dirstate
 
             srcrepo.hook(
                 b'outgoing', source=b'clone', node=srcrepo.nodeconstants.nullhex
             )
         else:
             try:
                 # only pass ui when no srcrepo
                 destpeer = peer(
                     srcrepo or ui,
                     peeropts,
                     dest,
                     create=True,
                     createopts=createopts,
                 )
             except FileExistsError:
                 cleandir = None
                 raise error.Abort(_(b"destination '%s' already exists") % dest)
 
             if revs:
                 if not srcpeer.capable(b'lookup'):
                     raise error.Abort(
                         _(
                             b"src repository does not support "
                             b"revision lookup and so doesn't "
                             b"support clone by revision"
                         )
                     )
 
                 # TODO this is batchable.
                 remoterevs = []
                 for rev in revs:
                     with srcpeer.commandexecutor() as e:
                         remoterevs.append(
                             e.callcommand(
                                 b'lookup',
                                 {
                                     b'key': rev,
                                 },
                             ).result()
                         )
                 revs = remoterevs
 
                 checkout = revs[0]
             else:
                 revs = None
             local = destpeer.local()
             if local:
                 if narrow:
                     with local.wlock(), local.lock():
                         local.setnarrowpats(storeincludepats, storeexcludepats)
                         narrowspec.copytoworkingcopy(local)
 
                 u = urlutil.url(abspath)
                 defaulturl = bytes(u)
                 local.ui.setconfig(b'paths', b'default', defaulturl, b'clone')
                 if not stream:
                     if pull:
                         stream = False
                     else:
                         stream = None
                 # internal config: ui.quietbookmarkmove
                 overrides = {(b'ui', b'quietbookmarkmove'): True}
                 with local.ui.configoverride(overrides, b'clone'):
                     exchange.pull(
                         local,
                         srcpeer,
                         heads=revs,
                         streamclonerequested=stream,
                         includepats=storeincludepats,
                         excludepats=storeexcludepats,
                         depth=depth,
                     )
             elif srcrepo:
                 # TODO lift restriction once exchange.push() accepts narrow
                 # push.
                 if narrow:
                     raise error.Abort(
                         _(
                             b'narrow clone not available for '
                             b'remote destinations'
                         )
                     )
 
                 exchange.push(
                     srcrepo,
                     destpeer,
                     revs=revs,
                     bookmarks=srcrepo._bookmarks.keys(),
                 )
             else:
                 raise error.Abort(
                     _(b"clone from remote to remote not supported")
                 )
 
         cleandir = None
 
         destrepo = destpeer.local()
         if destrepo:
             template = uimod.samplehgrcs[b'cloned']
             u = urlutil.url(abspath)
             u.passwd = None
             defaulturl = bytes(u)
             destrepo.vfs.write(b'hgrc', util.tonativeeol(template % defaulturl))
             destrepo.ui.setconfig(b'paths', b'default', defaulturl, b'clone')
 
             if ui.configbool(b'experimental', b'remotenames'):
                 logexchange.pullremotenames(destrepo, srcpeer)
 
             if update:
                 if update is not True:
                     with srcpeer.commandexecutor() as e:
                         checkout = e.callcommand(
                             b'lookup',
                             {
                                 b'key': update,
                             },
                         ).result()
 
                 uprev = None
                 status = None
                 if checkout is not None:
                     # Some extensions (at least hg-git and hg-subversion) have
                     # a peer.lookup() implementation that returns a name instead
                     # of a nodeid. We work around it here until we've figured
                     # out a better solution.
                     if len(checkout) == 20 and checkout in destrepo:
                         uprev = checkout
                     elif scmutil.isrevsymbol(destrepo, checkout):
                         uprev = scmutil.revsymbol(destrepo, checkout).node()
                     else:
                         if update is not True:
                             try:
                                 uprev = destrepo.lookup(update)
                             except error.RepoLookupError:
                                 pass
                 if uprev is None:
                     try:
                         if destrepo._activebookmark:
                             uprev = destrepo.lookup(destrepo._activebookmark)
                             update = destrepo._activebookmark
                         else:
                             uprev = destrepo._bookmarks[b'@']
                             update = b'@'
                         bn = destrepo[uprev].branch()
                         if bn == b'default':
                             status = _(b"updating to bookmark %s\n" % update)
                         else:
                             status = (
                                 _(b"updating to bookmark %s on branch %s\n")
                             ) % (update, bn)
                     except KeyError:
                         try:
                             uprev = destrepo.branchtip(b'default')
                         except error.RepoLookupError:
                             uprev = destrepo.lookup(b'tip')
                 if not status:
                     bn = destrepo[uprev].branch()
                     status = _(b"updating to branch %s\n") % bn
                 destrepo.ui.status(status)
                 _update(destrepo, uprev)
                 if update in destrepo._bookmarks:
                     bookmarks.activate(destrepo, update)
             if destlock is not None:
                 release(destlock)
             if destwlock is not None:
                 release(destlock)
             # here is a tiny windows were someone could end up writing the
             # repository before the cache are sure to be warm. This is "fine"
             # as the only "bad" outcome would be some slowness. That potential
             # slowness already affect reader.
             with destrepo.lock():
                 destrepo.updatecaches(caches=repositorymod.CACHES_POST_CLONE)
     finally:
         release(srclock, destlock, destwlock)
         if cleandir is not None:
             shutil.rmtree(cleandir, True)
         if srcpeer is not None:
             srcpeer.close()
         if destpeer and destpeer.local() is None:
             destpeer.close()
     return srcpeer, destpeer
 
 
 def _showstats(repo, stats, quietempty=False):
     if quietempty and stats.isempty():
         return
     repo.ui.status(
         _(
             b"%d files updated, %d files merged, "
             b"%d files removed, %d files unresolved\n"
         )
         % (
             stats.updatedcount,
             stats.mergedcount,
             stats.removedcount,
             stats.unresolvedcount,
         )
     )
 
 
 def updaterepo(repo, node, overwrite, updatecheck=None):
     """Update the working directory to node.
 
     When overwrite is set, changes are clobbered, merged else
 
     returns stats (see pydoc mercurial.merge.applyupdates)"""
     repo.ui.deprecwarn(
         b'prefer merge.update() or merge.clean_update() over hg.updaterepo()',
         b'5.7',
     )
     return mergemod._update(
         repo,
         node,
         branchmerge=False,
         force=overwrite,
         labels=[b'working copy', b'destination'],
         updatecheck=updatecheck,
     )
 
 
 def update(repo, node, quietempty=False, updatecheck=None):
     """update the working directory to node"""
     stats = mergemod.update(repo[node], updatecheck=updatecheck)
     _showstats(repo, stats, quietempty)
     if stats.unresolvedcount:
         repo.ui.status(_(b"use 'hg resolve' to retry unresolved file merges\n"))
     return stats.unresolvedcount > 0
 
 
 # naming conflict in clone()
 _update = update
 
 
 def clean(repo, node, show_stats=True, quietempty=False):
     """forcibly switch the working directory to node, clobbering changes"""
     stats = mergemod.clean_update(repo[node])
     assert stats.unresolvedcount == 0
     if show_stats:
         _showstats(repo, stats, quietempty)
     return False
 
 
 # naming conflict in updatetotally()
 _clean = clean
 
 _VALID_UPDATECHECKS = {
     mergemod.UPDATECHECK_ABORT,
     mergemod.UPDATECHECK_NONE,
     mergemod.UPDATECHECK_LINEAR,
     mergemod.UPDATECHECK_NO_CONFLICT,
 }
 
 
 def updatetotally(ui, repo, checkout, brev, clean=False, updatecheck=None):
     """Update the working directory with extra care for non-file components
 
     This takes care of non-file components below:
 
     :bookmark: might be advanced or (in)activated
 
     This takes arguments below:
 
     :checkout: to which revision the working directory is updated
     :brev: a name, which might be a bookmark to be activated after updating
     :clean: whether changes in the working directory can be discarded
     :updatecheck: how to deal with a dirty working directory
 
     Valid values for updatecheck are the UPDATECHECK_* constants
     defined in the merge module. Passing `None` will result in using the
     configured default.
 
      * ABORT: abort if the working directory is dirty
      * NONE: don't check (merge working directory changes into destination)
      * LINEAR: check that update is linear before merging working directory
                changes into destination
      * NO_CONFLICT: check that the update does not result in file merges
 
     This returns whether conflict is detected at updating or not.
     """
     if updatecheck is None:
         updatecheck = ui.config(b'commands', b'update.check')
         if updatecheck not in _VALID_UPDATECHECKS:
             # If not configured, or invalid value configured
             updatecheck = mergemod.UPDATECHECK_LINEAR
     if updatecheck not in _VALID_UPDATECHECKS:
         raise ValueError(
             r'Invalid updatecheck value %r (can accept %r)'
             % (updatecheck, _VALID_UPDATECHECKS)
         )
     with repo.wlock():
         movemarkfrom = None
         warndest = False
         if checkout is None:
             updata = destutil.destupdate(repo, clean=clean)
             checkout, movemarkfrom, brev = updata
             warndest = True
 
         if clean:
             ret = _clean(repo, checkout)
         else:
             if updatecheck == mergemod.UPDATECHECK_ABORT:
                 cmdutil.bailifchanged(repo, merge=False)
                 updatecheck = mergemod.UPDATECHECK_NONE
             ret = _update(repo, checkout, updatecheck=updatecheck)
 
         if not ret and movemarkfrom:
             if movemarkfrom == repo[b'.'].node():
                 pass  # no-op update
             elif bookmarks.update(repo, [movemarkfrom], repo[b'.'].node()):
                 b = ui.label(repo._activebookmark, b'bookmarks.active')
                 ui.status(_(b"updating bookmark %s\n") % b)
             else:
                 # this can happen with a non-linear update
                 b = ui.label(repo._activebookmark, b'bookmarks')
                 ui.status(_(b"(leaving bookmark %s)\n") % b)
                 bookmarks.deactivate(repo)
         elif brev in repo._bookmarks:
             if brev != repo._activebookmark:
                 b = ui.label(brev, b'bookmarks.active')
                 ui.status(_(b"(activating bookmark %s)\n") % b)
             bookmarks.activate(repo, brev)
         elif brev:
             if repo._activebookmark:
                 b = ui.label(repo._activebookmark, b'bookmarks')
                 ui.status(_(b"(leaving bookmark %s)\n") % b)
             bookmarks.deactivate(repo)
 
         if warndest:
             destutil.statusotherdests(ui, repo)
 
     return ret
 
 
 def merge(
     ctx,
     force=False,
     remind=True,
     labels=None,
 ):
     """Branch merge with node, resolving changes. Return true if any
     unresolved conflicts."""
     repo = ctx.repo()
     stats = mergemod.merge(ctx, force=force, labels=labels)
     _showstats(repo, stats)
     if stats.unresolvedcount:
         repo.ui.status(
             _(
                 b"use 'hg resolve' to retry unresolved file merges "
                 b"or 'hg merge --abort' to abandon\n"
             )
         )
     elif remind:
         repo.ui.status(_(b"(branch merge, don't forget to commit)\n"))
     return stats.unresolvedcount > 0
 
 
 def abortmerge(ui, repo):
     ms = mergestatemod.mergestate.read(repo)
     if ms.active():
         # there were conflicts
         node = ms.localctx.hex()
     else:
         # there were no conficts, mergestate was not stored
         node = repo[b'.'].hex()
 
     repo.ui.status(_(b"aborting the merge, updating back to %s\n") % node[:12])
     stats = mergemod.clean_update(repo[node])
     assert stats.unresolvedcount == 0
     _showstats(repo, stats)
 
 
 def _incoming(
     displaychlist,
     subreporecurse,
     ui,
     repo,
     source,
     opts,
     buffered=False,
     subpath=None,
 ):
     """
     Helper for incoming / gincoming.
     displaychlist gets called with
         (remoterepo, incomingchangesetlist, displayer) parameters,
     and is supposed to contain only code that can't be unified.
     """
     srcs = urlutil.get_pull_paths(repo, ui, [source])
     srcs = list(srcs)
     if len(srcs) != 1:
         msg = _(b'for now, incoming supports only a single source, %d provided')
         msg %= len(srcs)
         raise error.Abort(msg)
     path = srcs[0]
     if subpath is None:
         peer_path = path
         url = path.loc
     else:
         # XXX path: we are losing the `path` object here. Keeping it would be
         # valuable. For example as a "variant" as we do for pushes.
         subpath = urlutil.url(subpath)
         if subpath.isabs():
             peer_path = url = bytes(subpath)
         else:
             p = urlutil.url(path.loc)
             if p.islocal():
                 normpath = os.path.normpath
             else:
                 normpath = posixpath.normpath
             p.path = normpath(b'%s/%s' % (p.path, subpath))
             peer_path = url = bytes(p)
     other = peer(repo, opts, peer_path)
     cleanupfn = other.close
     try:
         ui.status(_(b'comparing with %s\n') % urlutil.hidepassword(url))
         branches = (path.branch, opts.get(b'branch', []))
         revs, checkout = addbranchrevs(repo, other, branches, opts.get(b'rev'))
 
         if revs:
             revs = [other.lookup(rev) for rev in revs]
         other, chlist, cleanupfn = bundlerepo.getremotechanges(
             ui, repo, other, revs, opts.get(b"bundle"), opts.get(b"force")
         )
 
         if not chlist:
             ui.status(_(b"no changes found\n"))
             return subreporecurse()
         ui.pager(b'incoming')
         displayer = logcmdutil.changesetdisplayer(
             ui, other, opts, buffered=buffered
         )
         displaychlist(other, chlist, displayer)
         displayer.close()
     finally:
         cleanupfn()
     subreporecurse()
     return 0  # exit code is zero since we found incoming changes
 
 
 def incoming(ui, repo, source, opts, subpath=None):
     def subreporecurse():
         ret = 1
         if opts.get(b'subrepos'):
             ctx = repo[None]
             for subpath in sorted(ctx.substate):
                 sub = ctx.sub(subpath)
                 ret = min(ret, sub.incoming(ui, source, opts))
         return ret
 
     def display(other, chlist, displayer):
         limit = logcmdutil.getlimit(opts)
         if opts.get(b'newest_first'):
             chlist.reverse()
         count = 0
         for n in chlist:
             if limit is not None and count >= limit:
                 break
             parents = [
                 p for p in other.changelog.parents(n) if p != repo.nullid
             ]
             if opts.get(b'no_merges') and len(parents) == 2:
                 continue
             count += 1
             displayer.show(other[n])
 
     return _incoming(
         display, subreporecurse, ui, repo, source, opts, subpath=subpath
     )
 
 
 def _outgoing(ui, repo, dests, opts, subpath=None):
     out = set()
     others = []
     for path in urlutil.get_push_paths(repo, ui, dests):
         dest = path.loc
         if subpath is not None:
             subpath = urlutil.url(subpath)
             if subpath.isabs():
                 dest = bytes(subpath)
             else:
                 p = urlutil.url(dest)
                 if p.islocal():
                     normpath = os.path.normpath
                 else:
                     normpath = posixpath.normpath
                 p.path = normpath(b'%s/%s' % (p.path, subpath))
                 dest = bytes(p)
         branches = path.branch, opts.get(b'branch') or []
 
         ui.status(_(b'comparing with %s\n') % urlutil.hidepassword(dest))
         revs, checkout = addbranchrevs(repo, repo, branches, opts.get(b'rev'))
         if revs:
             revs = [repo[rev].node() for rev in logcmdutil.revrange(repo, revs)]
 
         other = peer(repo, opts, dest)
         try:
             outgoing = discovery.findcommonoutgoing(
                 repo, other, revs, force=opts.get(b'force')
             )
             o = outgoing.missing
             out.update(o)
             if not o:
                 scmutil.nochangesfound(repo.ui, repo, outgoing.excluded)
             others.append(other)
         except:  # re-raises
             other.close()
             raise
     # make sure this is ordered by revision number
     outgoing_revs = list(out)
     cl = repo.changelog
     outgoing_revs.sort(key=cl.rev)
     return outgoing_revs, others
 
 
 def _outgoing_recurse(ui, repo, dests, opts):
     ret = 1
     if opts.get(b'subrepos'):
         ctx = repo[None]
         for subpath in sorted(ctx.substate):
             sub = ctx.sub(subpath)
             ret = min(ret, sub.outgoing(ui, dests, opts))
     return ret
 
 
 def _outgoing_filter(repo, revs, opts):
     """apply revision filtering/ordering option for outgoing"""
     limit = logcmdutil.getlimit(opts)
     no_merges = opts.get(b'no_merges')
     if opts.get(b'newest_first'):
         revs.reverse()
     if limit is None and not no_merges:
         for r in revs:
             yield r
         return
 
     count = 0
     cl = repo.changelog
     for n in revs:
         if limit is not None and count >= limit:
             break
         parents = [p for p in cl.parents(n) if p != repo.nullid]
         if no_merges and len(parents) == 2:
             continue
         count += 1
         yield n
 
 
 def outgoing(ui, repo, dests, opts, subpath=None):
     if opts.get(b'graph'):
         logcmdutil.checkunsupportedgraphflags([], opts)
     o, others = _outgoing(ui, repo, dests, opts, subpath=subpath)
     ret = 1
     try:
         if o:
             ret = 0
 
             if opts.get(b'graph'):
                 revdag = logcmdutil.graphrevs(repo, o, opts)
                 ui.pager(b'outgoing')
                 displayer = logcmdutil.changesetdisplayer(
                     ui, repo, opts, buffered=True
                 )
                 logcmdutil.displaygraph(
                     ui, repo, revdag, displayer, graphmod.asciiedges
                 )
             else:
                 ui.pager(b'outgoing')
                 displayer = logcmdutil.changesetdisplayer(ui, repo, opts)
                 for n in _outgoing_filter(repo, o, opts):
                     displayer.show(repo[n])
                 displayer.close()
         for oth in others:
             cmdutil.outgoinghooks(ui, repo, oth, opts, o)
             ret = min(ret, _outgoing_recurse(ui, repo, dests, opts))
         return ret  # exit code is zero since we found outgoing changes
     finally:
         for oth in others:
             oth.close()
 
 
 def verify(repo, level=None):
     """verify the consistency of a repository"""
     ret = verifymod.verify(repo, level=level)
 
     # Broken subrepo references in hidden csets don't seem worth worrying about,
     # since they can't be pushed/pulled, and --hidden can be used if they are a
     # concern.
 
     # pathto() is needed for -R case
     revs = repo.revs(
         b"filelog(%s)", util.pathto(repo.root, repo.getcwd(), b'.hgsubstate')
     )
 
     if revs:
         repo.ui.status(_(b'checking subrepo links\n'))
         for rev in revs:
             ctx = repo[rev]
             try:
                 for subpath in ctx.substate:
                     try:
                         ret = (
                             ctx.sub(subpath, allowcreate=False).verify() or ret
                         )
                     except error.RepoError as e:
                         repo.ui.warn(b'%d: %s\n' % (rev, e))
             except Exception:
                 repo.ui.warn(
                     _(b'.hgsubstate is corrupt in revision %s\n')
                     % short(ctx.node())
                 )
 
     return ret
 
 
 def remoteui(src, opts):
     """build a remote ui from ui or repo and opts"""
     if util.safehasattr(src, b'baseui'):  # looks like a repository
         dst = src.baseui.copy()  # drop repo-specific config
         src = src.ui  # copy target options from repo
     else:  # assume it's a global ui object
         dst = src.copy()  # keep all global options
 
     # copy ssh-specific options
     for o in b'ssh', b'remotecmd':
         v = opts.get(o) or src.config(b'ui', o)
         if v:
             dst.setconfig(b"ui", o, v, b'copied')
 
     # copy bundle-specific options
     r = src.config(b'bundle', b'mainreporoot')
     if r:
         dst.setconfig(b'bundle', b'mainreporoot', r, b'copied')
 
     # copy selected local settings to the remote ui
     for sect in (b'auth', b'hostfingerprints', b'hostsecurity', b'http_proxy'):
         for key, val in src.configitems(sect):
             dst.setconfig(sect, key, val, b'copied')
     v = src.config(b'web', b'cacerts')
     if v:
         dst.setconfig(b'web', b'cacerts', util.expandpath(v), b'copied')
 
     return dst
 
 
 # Files of interest
 # Used to check if the repository has changed looking at mtime and size of
 # these files.
 foi = [
     (b'spath', b'00changelog.i'),
     (b'spath', b'phaseroots'),  # ! phase can change content at the same size
     (b'spath', b'obsstore'),
     (b'path', b'bookmarks'),  # ! bookmark can change content at the same size
 ]
 
 
 class cachedlocalrepo:
     """Holds a localrepository that can be cached and reused."""
 
     def __init__(self, repo):
         """Create a new cached repo from an existing repo.
 
         We assume the passed in repo was recently created. If the
         repo has changed between when it was created and when it was
         turned into a cache, it may not refresh properly.
         """
         assert isinstance(repo, localrepo.localrepository)
         self._repo = repo
         self._state, self.mtime = self._repostate()
         self._filtername = repo.filtername
 
     def fetch(self):
         """Refresh (if necessary) and return a repository.
 
         If the cached instance is out of date, it will be recreated
         automatically and returned.
 
         Returns a tuple of the repo and a boolean indicating whether a new
         repo instance was created.
         """
         # We compare the mtimes and sizes of some well-known files to
         # determine if the repo changed. This is not precise, as mtimes
         # are susceptible to clock skew and imprecise filesystems and
         # file content can change while maintaining the same size.
 
         state, mtime = self._repostate()
         if state == self._state:
             return self._repo, False
 
         repo = repository(self._repo.baseui, self._repo.url())
         if self._filtername:
             self._repo = repo.filtered(self._filtername)
         else:
             self._repo = repo.unfiltered()
         self._state = state
         self.mtime = mtime
 
         return self._repo, True
 
     def _repostate(self):
         state = []
         maxmtime = -1
         for attr, fname in foi:
             prefix = getattr(self._repo, attr)
             p = os.path.join(prefix, fname)
             try:
                 st = os.stat(p)
             except OSError:
                 st = os.stat(prefix)
             state.append((st[stat.ST_MTIME], st.st_size))
             maxmtime = max(maxmtime, st[stat.ST_MTIME])
 
         return tuple(state), maxmtime
 
     def copy(self):
         """Obtain a copy of this class instance.
 
         A new localrepository instance is obtained. The new instance should be
         completely independent of the original.
         """
         repo = repository(self._repo.baseui, self._repo.origroot)
         if self._filtername:
             repo = repo.filtered(self._filtername)
         else:
             repo = repo.unfiltered()
         c = cachedlocalrepo(repo)
         c._state = self._state
         c.mtime = self.mtime
         return c