cmdutil: remove remainder of old walkchangerevs() implementation

hgext/remotefilelog/__init__.py

@@ -1,1291 +1,1255
 # __init__.py - remotefilelog extension
 #
 # Copyright 2013 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.
 """remotefilelog causes Mercurial to lazilly fetch file contents (EXPERIMENTAL)
 
 This extension is HIGHLY EXPERIMENTAL. There are NO BACKWARDS COMPATIBILITY
 GUARANTEES. This means that repositories created with this extension may
 only be usable with the exact version of this extension/Mercurial that was
 used. The extension attempts to enforce this in order to prevent repository
 corruption.
 
 remotefilelog works by fetching file contents lazily and storing them
 in a cache on the client rather than in revlogs. This allows enormous
 histories to be transferred only partially, making them easier to
 operate on.
 
 Configs:
 
     ``packs.maxchainlen`` specifies the maximum delta chain length in pack files
 
     ``packs.maxpacksize`` specifies the maximum pack file size
 
     ``packs.maxpackfilecount`` specifies the maximum number of packs in the
       shared cache (trees only for now)
 
     ``remotefilelog.backgroundprefetch`` runs prefetch in background when True
 
     ``remotefilelog.bgprefetchrevs`` specifies revisions to fetch on commit and
       update, and on other commands that use them. Different from pullprefetch.
 
     ``remotefilelog.gcrepack`` does garbage collection during repack when True
 
     ``remotefilelog.nodettl`` specifies maximum TTL of a node in seconds before
       it is garbage collected
 
     ``remotefilelog.repackonhggc`` runs repack on hg gc when True
 
     ``remotefilelog.prefetchdays`` specifies the maximum age of a commit in
       days after which it is no longer prefetched.
 
     ``remotefilelog.prefetchdelay`` specifies delay between background
       prefetches in seconds after operations that change the working copy parent
 
     ``remotefilelog.data.gencountlimit`` constraints the minimum number of data
       pack files required to be considered part of a generation. In particular,
       minimum number of packs files > gencountlimit.
 
     ``remotefilelog.data.generations`` list for specifying the lower bound of
       each generation of the data pack files. For example, list ['100MB','1MB']
       or ['1MB', '100MB'] will lead to three generations: [0, 1MB), [
       1MB, 100MB) and [100MB, infinity).
 
     ``remotefilelog.data.maxrepackpacks`` the maximum number of pack files to
       include in an incremental data repack.
 
     ``remotefilelog.data.repackmaxpacksize`` the maximum size of a pack file for
       it to be considered for an incremental data repack.
 
     ``remotefilelog.data.repacksizelimit`` the maximum total size of pack files
       to include in an incremental data repack.
 
     ``remotefilelog.history.gencountlimit`` constraints the minimum number of
       history pack files required to be considered part of a generation. In
       particular, minimum number of packs files > gencountlimit.
 
     ``remotefilelog.history.generations`` list for specifying the lower bound of
       each generation of the history pack files. For example, list [
       '100MB', '1MB'] or ['1MB', '100MB'] will lead to three generations: [
       0, 1MB), [1MB, 100MB) and [100MB, infinity).
 
     ``remotefilelog.history.maxrepackpacks`` the maximum number of pack files to
       include in an incremental history repack.
 
     ``remotefilelog.history.repackmaxpacksize`` the maximum size of a pack file
       for it to be considered for an incremental history repack.
 
     ``remotefilelog.history.repacksizelimit`` the maximum total size of pack
       files to include in an incremental history repack.
 
     ``remotefilelog.backgroundrepack`` automatically consolidate packs in the
       background
 
     ``remotefilelog.cachepath`` path to cache
 
     ``remotefilelog.cachegroup`` if set, make cache directory sgid to this
       group
 
     ``remotefilelog.cacheprocess`` binary to invoke for fetching file data
 
     ``remotefilelog.debug`` turn on remotefilelog-specific debug output
 
     ``remotefilelog.excludepattern`` pattern of files to exclude from pulls
 
     ``remotefilelog.includepattern`` pattern of files to include in pulls
 
     ``remotefilelog.fetchwarning``: message to print when too many
       single-file fetches occur
 
     ``remotefilelog.getfilesstep`` number of files to request in a single RPC
 
     ``remotefilelog.getfilestype`` if set to 'threaded' use threads to fetch
       files, otherwise use optimistic fetching
 
     ``remotefilelog.pullprefetch`` revset for selecting files that should be
       eagerly downloaded rather than lazily
 
     ``remotefilelog.reponame`` name of the repo. If set, used to partition
       data from other repos in a shared store.
 
     ``remotefilelog.server`` if true, enable server-side functionality
 
     ``remotefilelog.servercachepath`` path for caching blobs on the server
 
     ``remotefilelog.serverexpiration`` number of days to keep cached server
       blobs
 
     ``remotefilelog.validatecache`` if set, check cache entries for corruption
       before returning blobs
 
     ``remotefilelog.validatecachelog`` if set, check cache entries for
       corruption before returning metadata
 
 """
 from __future__ import absolute_import
 
 import os
 import time
 import traceback
 
 from mercurial.node import hex
 from mercurial.i18n import _
 from mercurial.pycompat import open
 from mercurial import (
     changegroup,
     changelog,
-    cmdutil,
     commands,
     configitems,
     context,
     copies,
     debugcommands as hgdebugcommands,
     dispatch,
     error,
     exchange,
     extensions,
     hg,
     localrepo,
     match as matchmod,
     merge,
     mergestate as mergestatemod,
     node as nodemod,
     patch,
     pycompat,
     registrar,
     repair,
     repoview,
     revset,
     scmutil,
     smartset,
     streamclone,
     util,
 )
 from . import (
     constants,
     debugcommands,
     fileserverclient,
     remotefilectx,
     remotefilelog,
     remotefilelogserver,
     repack as repackmod,
     shallowbundle,
     shallowrepo,
     shallowstore,
     shallowutil,
     shallowverifier,
 )
 
 # ensures debug commands are registered
 hgdebugcommands.command
 
 cmdtable = {}
 command = registrar.command(cmdtable)
 
 configtable = {}
 configitem = registrar.configitem(configtable)
 
 configitem(b'remotefilelog', b'debug', default=False)
 
 configitem(b'remotefilelog', b'reponame', default=b'')
 configitem(b'remotefilelog', b'cachepath', default=None)
 configitem(b'remotefilelog', b'cachegroup', default=None)
 configitem(b'remotefilelog', b'cacheprocess', default=None)
 configitem(b'remotefilelog', b'cacheprocess.includepath', default=None)
 configitem(b"remotefilelog", b"cachelimit", default=b"1000 GB")
 
 configitem(
     b'remotefilelog',
     b'fallbackpath',
     default=configitems.dynamicdefault,
     alias=[(b'remotefilelog', b'fallbackrepo')],
 )
 
 configitem(b'remotefilelog', b'validatecachelog', default=None)
 configitem(b'remotefilelog', b'validatecache', default=b'on')
 configitem(b'remotefilelog', b'server', default=None)
 configitem(b'remotefilelog', b'servercachepath', default=None)
 configitem(b"remotefilelog", b"serverexpiration", default=30)
 configitem(b'remotefilelog', b'backgroundrepack', default=False)
 configitem(b'remotefilelog', b'bgprefetchrevs', default=None)
 configitem(b'remotefilelog', b'pullprefetch', default=None)
 configitem(b'remotefilelog', b'backgroundprefetch', default=False)
 configitem(b'remotefilelog', b'prefetchdelay', default=120)
 configitem(b'remotefilelog', b'prefetchdays', default=14)
 
 configitem(b'remotefilelog', b'getfilesstep', default=10000)
 configitem(b'remotefilelog', b'getfilestype', default=b'optimistic')
 configitem(b'remotefilelog', b'batchsize', configitems.dynamicdefault)
 configitem(b'remotefilelog', b'fetchwarning', default=b'')
 
 configitem(b'remotefilelog', b'includepattern', default=None)
 configitem(b'remotefilelog', b'excludepattern', default=None)
 
 configitem(b'remotefilelog', b'gcrepack', default=False)
 configitem(b'remotefilelog', b'repackonhggc', default=False)
 configitem(b'repack', b'chainorphansbysize', default=True, experimental=True)
 
 configitem(b'packs', b'maxpacksize', default=0)
 configitem(b'packs', b'maxchainlen', default=1000)
 
 configitem(b'devel', b'remotefilelog.bg-wait', default=False)
 
 #  default TTL limit is 30 days
 _defaultlimit = 60 * 60 * 24 * 30
 configitem(b'remotefilelog', b'nodettl', default=_defaultlimit)
 
 configitem(b'remotefilelog', b'data.gencountlimit', default=2),
 configitem(
     b'remotefilelog', b'data.generations', default=[b'1GB', b'100MB', b'1MB']
 )
 configitem(b'remotefilelog', b'data.maxrepackpacks', default=50)
 configitem(b'remotefilelog', b'data.repackmaxpacksize', default=b'4GB')
 configitem(b'remotefilelog', b'data.repacksizelimit', default=b'100MB')
 
 configitem(b'remotefilelog', b'history.gencountlimit', default=2),
 configitem(b'remotefilelog', b'history.generations', default=[b'100MB'])
 configitem(b'remotefilelog', b'history.maxrepackpacks', default=50)
 configitem(b'remotefilelog', b'history.repackmaxpacksize', default=b'400MB')
 configitem(b'remotefilelog', b'history.repacksizelimit', default=b'100MB')
 
 # 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'
 
 repoclass = localrepo.localrepository
 repoclass._basesupported.add(constants.SHALLOWREPO_REQUIREMENT)
 
 isenabled = shallowutil.isenabled
 
 
 def uisetup(ui):
     """Wraps user facing Mercurial commands to swap them out with shallow
     versions.
     """
     hg.wirepeersetupfuncs.append(fileserverclient.peersetup)
 
     entry = extensions.wrapcommand(commands.table, b'clone', cloneshallow)
     entry[1].append(
         (
             b'',
             b'shallow',
             None,
             _(b"create a shallow clone which uses remote file history"),
         )
     )
 
     extensions.wrapcommand(
         commands.table, b'debugindex', debugcommands.debugindex
     )
     extensions.wrapcommand(
         commands.table, b'debugindexdot', debugcommands.debugindexdot
     )
     extensions.wrapcommand(commands.table, b'log', log)
     extensions.wrapcommand(commands.table, b'pull', pull)
 
     # Prevent 'hg manifest --all'
     def _manifest(orig, ui, repo, *args, **opts):
         if isenabled(repo) and opts.get('all'):
             raise error.Abort(_(b"--all is not supported in a shallow repo"))
 
         return orig(ui, repo, *args, **opts)
 
     extensions.wrapcommand(commands.table, b"manifest", _manifest)
 
     # Wrap remotefilelog with lfs code
     def _lfsloaded(loaded=False):
         lfsmod = None
         try:
             lfsmod = extensions.find(b'lfs')
         except KeyError:
             pass
         if lfsmod:
             lfsmod.wrapfilelog(remotefilelog.remotefilelog)
             fileserverclient._lfsmod = lfsmod
 
     extensions.afterloaded(b'lfs', _lfsloaded)
 
     # debugdata needs remotefilelog.len to work
     extensions.wrapcommand(commands.table, b'debugdata', debugdatashallow)
 
     changegroup.cgpacker = shallowbundle.shallowcg1packer
 
     extensions.wrapfunction(
         changegroup, b'_addchangegroupfiles', shallowbundle.addchangegroupfiles
     )
     extensions.wrapfunction(
         changegroup, b'makechangegroup', shallowbundle.makechangegroup
     )
     extensions.wrapfunction(localrepo, b'makestore', storewrapper)
     extensions.wrapfunction(exchange, b'pull', exchangepull)
     extensions.wrapfunction(merge, b'applyupdates', applyupdates)
     extensions.wrapfunction(merge, b'_checkunknownfiles', checkunknownfiles)
     extensions.wrapfunction(context.workingctx, b'_checklookup', checklookup)
     extensions.wrapfunction(scmutil, b'_findrenames', findrenames)
     extensions.wrapfunction(
         copies, b'_computeforwardmissing', computeforwardmissing
     )
     extensions.wrapfunction(dispatch, b'runcommand', runcommand)
     extensions.wrapfunction(repair, b'_collectbrokencsets', _collectbrokencsets)
     extensions.wrapfunction(context.changectx, b'filectx', filectx)
     extensions.wrapfunction(context.workingctx, b'filectx', workingfilectx)
     extensions.wrapfunction(patch, b'trydiff', trydiff)
     extensions.wrapfunction(hg, b'verify', _verify)
     scmutil.fileprefetchhooks.add(b'remotefilelog', _fileprefetchhook)
 
     # disappointing hacks below
     extensions.wrapfunction(scmutil, b'getrenamedfn', getrenamedfn)
     extensions.wrapfunction(revset, b'filelog', filelogrevset)
     revset.symbols[b'filelog'] = revset.filelog
-    extensions.wrapfunction(cmdutil, b'walkfilerevs', walkfilerevs)
 
 
 def cloneshallow(orig, ui, repo, *args, **opts):
     if opts.get('shallow'):
         repos = []
 
         def pull_shallow(orig, self, *args, **kwargs):
             if not isenabled(self):
                 repos.append(self.unfiltered())
                 # set up the client hooks so the post-clone update works
                 setupclient(self.ui, self.unfiltered())
 
                 # setupclient fixed the class on the repo itself
                 # but we also need to fix it on the repoview
                 if isinstance(self, repoview.repoview):
                     self.__class__.__bases__ = (
                         self.__class__.__bases__[0],
                         self.unfiltered().__class__,
                     )
                 self.requirements.add(constants.SHALLOWREPO_REQUIREMENT)
                 with self.lock():
                     # acquire store lock before writing requirements as some
                     # requirements might be written to .hg/store/requires
                     scmutil.writereporequirements(self)
 
                 # Since setupclient hadn't been called, exchange.pull was not
                 # wrapped. So we need to manually invoke our version of it.
                 return exchangepull(orig, self, *args, **kwargs)
             else:
                 return orig(self, *args, **kwargs)
 
         extensions.wrapfunction(exchange, b'pull', pull_shallow)
 
         # Wrap the stream logic to add requirements and to pass include/exclude
         # patterns around.
         def setup_streamout(repo, remote):
             # Replace remote.stream_out with a version that sends file
             # patterns.
             def stream_out_shallow(orig):
                 caps = remote.capabilities()
                 if constants.NETWORK_CAP_LEGACY_SSH_GETFILES in caps:
                     opts = {}
                     if repo.includepattern:
                         opts['includepattern'] = b'\0'.join(repo.includepattern)
                     if repo.excludepattern:
                         opts['excludepattern'] = b'\0'.join(repo.excludepattern)
                     return remote._callstream(b'stream_out_shallow', **opts)
                 else:
                     return orig()
 
             extensions.wrapfunction(remote, b'stream_out', stream_out_shallow)
 
         def stream_wrap(orig, op):
             setup_streamout(op.repo, op.remote)
             return orig(op)
 
         extensions.wrapfunction(
             streamclone, b'maybeperformlegacystreamclone', stream_wrap
         )
 
         def canperformstreamclone(orig, pullop, bundle2=False):
             # remotefilelog is currently incompatible with the
             # bundle2 flavor of streamclones, so force us to use
             # v1 instead.
             if b'v2' in pullop.remotebundle2caps.get(b'stream', []):
                 pullop.remotebundle2caps[b'stream'] = [
                     c for c in pullop.remotebundle2caps[b'stream'] if c != b'v2'
                 ]
             if bundle2:
                 return False, None
             supported, requirements = orig(pullop, bundle2=bundle2)
             if requirements is not None:
                 requirements.add(constants.SHALLOWREPO_REQUIREMENT)
             return supported, requirements
 
         extensions.wrapfunction(
             streamclone, b'canperformstreamclone', canperformstreamclone
         )
 
     try:
         orig(ui, repo, *args, **opts)
     finally:
         if opts.get('shallow'):
             for r in repos:
                 if util.safehasattr(r, b'fileservice'):
                     r.fileservice.close()
 
 
 def debugdatashallow(orig, *args, **kwds):
     oldlen = remotefilelog.remotefilelog.__len__
     try:
         remotefilelog.remotefilelog.__len__ = lambda x: 1
         return orig(*args, **kwds)
     finally:
         remotefilelog.remotefilelog.__len__ = oldlen
 
 
 def reposetup(ui, repo):
     if not repo.local():
         return
 
     # put here intentionally bc doesnt work in uisetup
     ui.setconfig(b'hooks', b'update.prefetch', wcpprefetch)
     ui.setconfig(b'hooks', b'commit.prefetch', wcpprefetch)
 
     isserverenabled = ui.configbool(b'remotefilelog', b'server')
     isshallowclient = isenabled(repo)
 
     if isserverenabled and isshallowclient:
         raise RuntimeError(b"Cannot be both a server and shallow client.")
 
     if isshallowclient:
         setupclient(ui, repo)
 
     if isserverenabled:
         remotefilelogserver.setupserver(ui, repo)
 
 
 def setupclient(ui, repo):
     if not isinstance(repo, localrepo.localrepository):
         return
 
     # Even clients get the server setup since they need to have the
     # wireprotocol endpoints registered.
     remotefilelogserver.onetimesetup(ui)
     onetimeclientsetup(ui)
 
     shallowrepo.wraprepo(repo)
     repo.store = shallowstore.wrapstore(repo.store)
 
 
 def storewrapper(orig, requirements, path, vfstype):
     s = orig(requirements, path, vfstype)
     if constants.SHALLOWREPO_REQUIREMENT in requirements:
         s = shallowstore.wrapstore(s)
 
     return s
 
 
 # prefetch files before update
 def applyupdates(
     orig, repo, mresult, wctx, mctx, overwrite, wantfiledata, **opts
 ):
     if isenabled(repo):
         manifest = mctx.manifest()
         files = []
         for f, args, msg in mresult.getactions([mergestatemod.ACTION_GET]):
             files.append((f, hex(manifest[f])))
         # batch fetch the needed files from the server
         repo.fileservice.prefetch(files)
     return orig(repo, mresult, wctx, mctx, overwrite, wantfiledata, **opts)
 
 
 # Prefetch merge checkunknownfiles
 def checkunknownfiles(orig, repo, wctx, mctx, force, mresult, *args, **kwargs):
     if isenabled(repo):
         files = []
         sparsematch = repo.maybesparsematch(mctx.rev())
         for f, (m, actionargs, msg) in mresult.filemap():
             if sparsematch and not sparsematch(f):
                 continue
             if m in (
                 mergestatemod.ACTION_CREATED,
                 mergestatemod.ACTION_DELETED_CHANGED,
                 mergestatemod.ACTION_CREATED_MERGE,
             ):
                 files.append((f, hex(mctx.filenode(f))))
             elif m == mergestatemod.ACTION_LOCAL_DIR_RENAME_GET:
                 f2 = actionargs[0]
                 files.append((f2, hex(mctx.filenode(f2))))
         # batch fetch the needed files from the server
         repo.fileservice.prefetch(files)
     return orig(repo, wctx, mctx, force, mresult, *args, **kwargs)
 
 
 # Prefetch files before status attempts to look at their size and contents
 def checklookup(orig, self, files):
     repo = self._repo
     if isenabled(repo):
         prefetchfiles = []
         for parent in self._parents:
             for f in files:
                 if f in parent:
                     prefetchfiles.append((f, hex(parent.filenode(f))))
         # batch fetch the needed files from the server
         repo.fileservice.prefetch(prefetchfiles)
     return orig(self, files)
 
 
 # Prefetch the logic that compares added and removed files for renames
 def findrenames(orig, repo, matcher, added, removed, *args, **kwargs):
     if isenabled(repo):
         files = []
         pmf = repo[b'.'].manifest()
         for f in removed:
             if f in pmf:
                 files.append((f, hex(pmf[f])))
         # batch fetch the needed files from the server
         repo.fileservice.prefetch(files)
     return orig(repo, matcher, added, removed, *args, **kwargs)
 
 
 # prefetch files before pathcopies check
 def computeforwardmissing(orig, a, b, match=None):
     missing = orig(a, b, match=match)
     repo = a._repo
     if isenabled(repo):
         mb = b.manifest()
 
         files = []
         sparsematch = repo.maybesparsematch(b.rev())
         if sparsematch:
             sparsemissing = set()
             for f in missing:
                 if sparsematch(f):
                     files.append((f, hex(mb[f])))
                     sparsemissing.add(f)
             missing = sparsemissing
 
         # batch fetch the needed files from the server
         repo.fileservice.prefetch(files)
     return missing
 
 
 # close cache miss server connection after the command has finished
 def runcommand(orig, lui, repo, *args, **kwargs):
     fileservice = None
     # repo can be None when running in chg:
     # - at startup, reposetup was called because serve is not norepo
     # - a norepo command like "help" is called
     if repo and isenabled(repo):
         fileservice = repo.fileservice
     try:
         return orig(lui, repo, *args, **kwargs)
     finally:
         if fileservice:
             fileservice.close()
 
 
 # prevent strip from stripping remotefilelogs
 def _collectbrokencsets(orig, repo, files, striprev):
     if isenabled(repo):
         files = list([f for f in files if not repo.shallowmatch(f)])
     return orig(repo, files, striprev)
 
 
 # changectx wrappers
 def filectx(orig, self, path, fileid=None, filelog=None):
     if fileid is None:
         fileid = self.filenode(path)
     if isenabled(self._repo) and self._repo.shallowmatch(path):
         return remotefilectx.remotefilectx(
             self._repo, path, fileid=fileid, changectx=self, filelog=filelog
         )
     return orig(self, path, fileid=fileid, filelog=filelog)
 
 
 def workingfilectx(orig, self, path, filelog=None):
     if isenabled(self._repo) and self._repo.shallowmatch(path):
         return remotefilectx.remoteworkingfilectx(
             self._repo, path, workingctx=self, filelog=filelog
         )
     return orig(self, path, filelog=filelog)
 
 
 # prefetch required revisions before a diff
 def trydiff(
     orig,
     repo,
     revs,
     ctx1,
     ctx2,
     modified,
     added,
     removed,
     copy,
     getfilectx,
     *args,
     **kwargs
 ):
     if isenabled(repo):
         prefetch = []
         mf1 = ctx1.manifest()
         for fname in modified + added + removed:
             if fname in mf1:
                 fnode = getfilectx(fname, ctx1).filenode()
                 # fnode can be None if it's a edited working ctx file
                 if fnode:
                     prefetch.append((fname, hex(fnode)))
             if fname not in removed:
                 fnode = getfilectx(fname, ctx2).filenode()
                 if fnode:
                     prefetch.append((fname, hex(fnode)))
 
         repo.fileservice.prefetch(prefetch)
 
     return orig(
         repo,
         revs,
         ctx1,
         ctx2,
         modified,
         added,
         removed,
         copy,
         getfilectx,
         *args,
         **kwargs
     )
 
 
 # Prevent verify from processing files
 # a stub for mercurial.hg.verify()
 def _verify(orig, repo, level=None):
     lock = repo.lock()
     try:
         return shallowverifier.shallowverifier(repo).verify()
     finally:
         lock.release()
 
 
 clientonetime = False
 
 
 def onetimeclientsetup(ui):
     global clientonetime
     if clientonetime:
         return
     clientonetime = True
 
     # Don't commit filelogs until we know the commit hash, since the hash
     # is present in the filelog blob.
     # This violates Mercurial's filelog->manifest->changelog write order,
     # but is generally fine for client repos.
     pendingfilecommits = []
 
     def addrawrevision(
         orig,
         self,
         rawtext,
         transaction,
         link,
         p1,
         p2,
         node,
         flags,
         cachedelta=None,
         _metatuple=None,
     ):
         if isinstance(link, int):
             pendingfilecommits.append(
                 (
                     self,
                     rawtext,
                     transaction,
                     link,
                     p1,
                     p2,
                     node,
                     flags,
                     cachedelta,
                     _metatuple,
                 )
             )
             return node
         else:
             return orig(
                 self,
                 rawtext,
                 transaction,
                 link,
                 p1,
                 p2,
                 node,
                 flags,
                 cachedelta,
                 _metatuple=_metatuple,
             )
 
     extensions.wrapfunction(
         remotefilelog.remotefilelog, b'addrawrevision', addrawrevision
     )
 
     def changelogadd(orig, self, *args, **kwargs):
         oldlen = len(self)
         node = orig(self, *args, **kwargs)
         newlen = len(self)
         if oldlen != newlen:
             for oldargs in pendingfilecommits:
                 log, rt, tr, link, p1, p2, n, fl, c, m = oldargs
                 linknode = self.node(link)
                 if linknode == node:
                     log.addrawrevision(rt, tr, linknode, p1, p2, n, fl, c, m)
                 else:
                     raise error.ProgrammingError(
                         b'pending multiple integer revisions are not supported'
                     )
         else:
             # "link" is actually wrong here (it is set to len(changelog))
             # if changelog remains unchanged, skip writing file revisions
             # but still do a sanity check about pending multiple revisions
             if len({x[3] for x in pendingfilecommits}) > 1:
                 raise error.ProgrammingError(
                     b'pending multiple integer revisions are not supported'
                 )
         del pendingfilecommits[:]
         return node
 
     extensions.wrapfunction(changelog.changelog, b'add', changelogadd)
 
 
 def getrenamedfn(orig, repo, endrev=None):
     if not isenabled(repo) or copies.usechangesetcentricalgo(repo):
         return orig(repo, endrev)
 
     rcache = {}
 
     def getrenamed(fn, rev):
         '''looks up all renames for a file (up to endrev) the first
         time the file is given. It indexes on the changerev and only
         parses the manifest if linkrev != changerev.
         Returns rename info for fn at changerev rev.'''
         if rev in rcache.setdefault(fn, {}):
             return rcache[fn][rev]
 
         try:
             fctx = repo[rev].filectx(fn)
             for ancestor in fctx.ancestors():
                 if ancestor.path() == fn:
                     renamed = ancestor.renamed()
                     rcache[fn][ancestor.rev()] = renamed and renamed[0]
 
             renamed = fctx.renamed()
             return renamed and renamed[0]
         except error.LookupError:
             return None
 
     return getrenamed
 
 
-def walkfilerevs(orig, repo, match, follow, revs, fncache):
-    if not isenabled(repo):
-        return orig(repo, match, follow, revs, fncache)
-
-    # remotefilelog's can't be walked in rev order, so throw.
-    # The caller will see the exception and walk the commit tree instead.
-    if not follow:
-        raise cmdutil.FileWalkError(b"Cannot walk via filelog")
-
-    wanted = set()
-    minrev, maxrev = min(revs), max(revs)
-
-    pctx = repo[b'.']
-    for filename in match.files():
-        if filename not in pctx:
-            raise error.Abort(
-                _(b'cannot follow file not in parent revision: "%s"') % filename
-            )
-        fctx = pctx[filename]
-
-        linkrev = fctx.linkrev()
-        if linkrev >= minrev and linkrev <= maxrev:
-            fncache.setdefault(linkrev, []).append(filename)
-            wanted.add(linkrev)
-
-        for ancestor in fctx.ancestors():
-            linkrev = ancestor.linkrev()
-            if linkrev >= minrev and linkrev <= maxrev:
-                fncache.setdefault(linkrev, []).append(ancestor.path())
-                wanted.add(linkrev)
-
-    return wanted
-
-
 def filelogrevset(orig, repo, subset, x):
     """``filelog(pattern)``
     Changesets connected to the specified filelog.
 
     For performance reasons, ``filelog()`` does not show every changeset
     that affects the requested file(s). See :hg:`help log` for details. For
     a slower, more accurate result, use ``file()``.
     """
 
     if not isenabled(repo):
         return orig(repo, subset, x)
 
     # i18n: "filelog" is a keyword
     pat = revset.getstring(x, _(b"filelog requires a pattern"))
     m = matchmod.match(
         repo.root, repo.getcwd(), [pat], default=b'relpath', ctx=repo[None]
     )
     s = set()
 
     if not matchmod.patkind(pat):
         # slow
         for r in subset:
             ctx = repo[r]
             cfiles = ctx.files()
             for f in m.files():
                 if f in cfiles:
                     s.add(ctx.rev())
                     break
     else:
         # partial
         files = (f for f in repo[None] if m(f))
         for f in files:
             fctx = repo[None].filectx(f)
             s.add(fctx.linkrev())
             for actx in fctx.ancestors():
                 s.add(actx.linkrev())
 
     return smartset.baseset([r for r in subset if r in s])
 
 
 @command(b'gc', [], _(b'hg gc [REPO...]'), norepo=True)
 def gc(ui, *args, **opts):
     '''garbage collect the client and server filelog caches
     '''
     cachepaths = set()
 
     # get the system client cache
     systemcache = shallowutil.getcachepath(ui, allowempty=True)
     if systemcache:
         cachepaths.add(systemcache)
 
     # get repo client and server cache
     repopaths = []
     pwd = ui.environ.get(b'PWD')
     if pwd:
         repopaths.append(pwd)
 
     repopaths.extend(args)
     repos = []
     for repopath in repopaths:
         try:
             repo = hg.peer(ui, {}, repopath)
             repos.append(repo)
 
             repocache = shallowutil.getcachepath(repo.ui, allowempty=True)
             if repocache:
                 cachepaths.add(repocache)
         except error.RepoError:
             pass
 
     # gc client cache
     for cachepath in cachepaths:
         gcclient(ui, cachepath)
 
     # gc server cache
     for repo in repos:
         remotefilelogserver.gcserver(ui, repo._repo)
 
 
 def gcclient(ui, cachepath):
     # get list of repos that use this cache
     repospath = os.path.join(cachepath, b'repos')
     if not os.path.exists(repospath):
         ui.warn(_(b"no known cache at %s\n") % cachepath)
         return
 
     reposfile = open(repospath, b'rb')
     repos = {r[:-1] for r in reposfile.readlines()}
     reposfile.close()
 
     # build list of useful files
     validrepos = []
     keepkeys = set()
 
     sharedcache = None
     filesrepacked = False
 
     count = 0
     progress = ui.makeprogress(
         _(b"analyzing repositories"), unit=b"repos", total=len(repos)
     )
     for path in repos:
         progress.update(count)
         count += 1
         try:
             path = ui.expandpath(os.path.normpath(path))
         except TypeError as e:
             ui.warn(_(b"warning: malformed path: %r:%s\n") % (path, e))
             traceback.print_exc()
             continue
         try:
             peer = hg.peer(ui, {}, path)
             repo = peer._repo
         except error.RepoError:
             continue
 
         validrepos.append(path)
 
         # Protect against any repo or config changes that have happened since
         # this repo was added to the repos file. We'd rather this loop succeed
         # and too much be deleted, than the loop fail and nothing gets deleted.
         if not isenabled(repo):
             continue
 
         if not util.safehasattr(repo, b'name'):
             ui.warn(
                 _(b"repo %s is a misconfigured remotefilelog repo\n") % path
             )
             continue
 
         # If garbage collection on repack and repack on hg gc are enabled
         # then loose files are repacked and garbage collected.
         # Otherwise regular garbage collection is performed.
         repackonhggc = repo.ui.configbool(b'remotefilelog', b'repackonhggc')
         gcrepack = repo.ui.configbool(b'remotefilelog', b'gcrepack')
         if repackonhggc and gcrepack:
             try:
                 repackmod.incrementalrepack(repo)
                 filesrepacked = True
                 continue
             except (IOError, repackmod.RepackAlreadyRunning):
                 # If repack cannot be performed due to not enough disk space
                 # continue doing garbage collection of loose files w/o repack
                 pass
 
         reponame = repo.name
         if not sharedcache:
             sharedcache = repo.sharedstore
 
         # Compute a keepset which is not garbage collected
         def keyfn(fname, fnode):
             return fileserverclient.getcachekey(reponame, fname, hex(fnode))
 
         keepkeys = repackmod.keepset(repo, keyfn=keyfn, lastkeepkeys=keepkeys)
 
     progress.complete()
 
     # write list of valid repos back
     oldumask = os.umask(0o002)
     try:
         reposfile = open(repospath, b'wb')
         reposfile.writelines([(b"%s\n" % r) for r in validrepos])
         reposfile.close()
     finally:
         os.umask(oldumask)
 
     # prune cache
     if sharedcache is not None:
         sharedcache.gc(keepkeys)
     elif not filesrepacked:
         ui.warn(_(b"warning: no valid repos in repofile\n"))
 
 
 def log(orig, ui, repo, *pats, **opts):
     if not isenabled(repo):
         return orig(ui, repo, *pats, **opts)
 
     follow = opts.get('follow')
     revs = opts.get('rev')
     if pats:
         # Force slowpath for non-follow patterns and follows that start from
         # non-working-copy-parent revs.
         if not follow or revs:
             # This forces the slowpath
             opts['removed'] = True
 
         # If this is a non-follow log without any revs specified, recommend that
         # the user add -f to speed it up.
         if not follow and not revs:
             match = scmutil.match(repo[b'.'], pats, pycompat.byteskwargs(opts))
             isfile = not match.anypats()
             if isfile:
                 for file in match.files():
                     if not os.path.isfile(repo.wjoin(file)):
                         isfile = False
                         break
 
             if isfile:
                 ui.warn(
                     _(
                         b"warning: file log can be slow on large repos - "
                         + b"use -f to speed it up\n"
                     )
                 )
 
     return orig(ui, repo, *pats, **opts)
 
 
 def revdatelimit(ui, revset):
     """Update revset so that only changesets no older than 'prefetchdays' days
     are included. The default value is set to 14 days. If 'prefetchdays' is set
     to zero or negative value then date restriction is not applied.
     """
     days = ui.configint(b'remotefilelog', b'prefetchdays')
     if days > 0:
         revset = b'(%s) & date(-%s)' % (revset, days)
     return revset
 
 
 def readytofetch(repo):
     """Check that enough time has passed since the last background prefetch.
     This only relates to prefetches after operations that change the working
     copy parent. Default delay between background prefetches is 2 minutes.
     """
     timeout = repo.ui.configint(b'remotefilelog', b'prefetchdelay')
     fname = repo.vfs.join(b'lastprefetch')
 
     ready = False
     with open(fname, b'a'):
         # the with construct above is used to avoid race conditions
         modtime = os.path.getmtime(fname)
         if (time.time() - modtime) > timeout:
             os.utime(fname, None)
             ready = True
 
     return ready
 
 
 def wcpprefetch(ui, repo, **kwargs):
     """Prefetches in background revisions specified by bgprefetchrevs revset.
     Does background repack if backgroundrepack flag is set in config.
     """
     shallow = isenabled(repo)
     bgprefetchrevs = ui.config(b'remotefilelog', b'bgprefetchrevs')
     isready = readytofetch(repo)
 
     if not (shallow and bgprefetchrevs and isready):
         return
 
     bgrepack = repo.ui.configbool(b'remotefilelog', b'backgroundrepack')
     # update a revset with a date limit
     bgprefetchrevs = revdatelimit(ui, bgprefetchrevs)
 
     def anon(unused_success):
         if util.safehasattr(repo, b'ranprefetch') and repo.ranprefetch:
             return
         repo.ranprefetch = True
         repo.backgroundprefetch(bgprefetchrevs, repack=bgrepack)
 
     repo._afterlock(anon)
 
 
 def pull(orig, ui, repo, *pats, **opts):
     result = orig(ui, repo, *pats, **opts)
 
     if isenabled(repo):
         # prefetch if it's configured
         prefetchrevset = ui.config(b'remotefilelog', b'pullprefetch')
         bgrepack = repo.ui.configbool(b'remotefilelog', b'backgroundrepack')
         bgprefetch = repo.ui.configbool(b'remotefilelog', b'backgroundprefetch')
 
         if prefetchrevset:
             ui.status(_(b"prefetching file contents\n"))
             revs = scmutil.revrange(repo, [prefetchrevset])
             base = repo[b'.'].rev()
             if bgprefetch:
                 repo.backgroundprefetch(prefetchrevset, repack=bgrepack)
             else:
                 repo.prefetch(revs, base=base)
                 if bgrepack:
                     repackmod.backgroundrepack(repo, incremental=True)
         elif bgrepack:
             repackmod.backgroundrepack(repo, incremental=True)
 
     return result
 
 
 def exchangepull(orig, repo, remote, *args, **kwargs):
     # Hook into the callstream/getbundle to insert bundle capabilities
     # during a pull.
     def localgetbundle(
         orig, source, heads=None, common=None, bundlecaps=None, **kwargs
     ):
         if not bundlecaps:
             bundlecaps = set()
         bundlecaps.add(constants.BUNDLE2_CAPABLITY)
         return orig(
             source, heads=heads, common=common, bundlecaps=bundlecaps, **kwargs
         )
 
     if util.safehasattr(remote, b'_callstream'):
         remote._localrepo = repo
     elif util.safehasattr(remote, b'getbundle'):
         extensions.wrapfunction(remote, b'getbundle', localgetbundle)
 
     return orig(repo, remote, *args, **kwargs)
 
 
 def _fileprefetchhook(repo, revmatches):
     if isenabled(repo):
         allfiles = []
         for rev, match in revmatches:
             if rev == nodemod.wdirrev or rev is None:
                 continue
             ctx = repo[rev]
             mf = ctx.manifest()
             sparsematch = repo.maybesparsematch(ctx.rev())
             for path in ctx.walk(match):
                 if (not sparsematch or sparsematch(path)) and path in mf:
                     allfiles.append((path, hex(mf[path])))
         repo.fileservice.prefetch(allfiles)
 
 
 @command(
     b'debugremotefilelog',
     [(b'd', b'decompress', None, _(b'decompress the filelog first')),],
     _(b'hg debugremotefilelog <path>'),
     norepo=True,
 )
 def debugremotefilelog(ui, path, **opts):
     return debugcommands.debugremotefilelog(ui, path, **opts)
 
 
 @command(
     b'verifyremotefilelog',
     [(b'd', b'decompress', None, _(b'decompress the filelogs first')),],
     _(b'hg verifyremotefilelogs <directory>'),
     norepo=True,
 )
 def verifyremotefilelog(ui, path, **opts):
     return debugcommands.verifyremotefilelog(ui, path, **opts)
 
 
 @command(
     b'debugdatapack',
     [
         (b'', b'long', None, _(b'print the long hashes')),
         (b'', b'node', b'', _(b'dump the contents of node'), b'NODE'),
     ],
     _(b'hg debugdatapack <paths>'),
     norepo=True,
 )
 def debugdatapack(ui, *paths, **opts):
     return debugcommands.debugdatapack(ui, *paths, **opts)
 
 
 @command(b'debughistorypack', [], _(b'hg debughistorypack <path>'), norepo=True)
 def debughistorypack(ui, path, **opts):
     return debugcommands.debughistorypack(ui, path)
 
 
 @command(b'debugkeepset', [], _(b'hg debugkeepset'))
 def debugkeepset(ui, repo, **opts):
     # The command is used to measure keepset computation time
     def keyfn(fname, fnode):
         return fileserverclient.getcachekey(repo.name, fname, hex(fnode))
 
     repackmod.keepset(repo, keyfn)
     return
 
 
 @command(b'debugwaitonrepack', [], _(b'hg debugwaitonrepack'))
 def debugwaitonrepack(ui, repo, **opts):
     return debugcommands.debugwaitonrepack(repo)
 
 
 @command(b'debugwaitonprefetch', [], _(b'hg debugwaitonprefetch'))
 def debugwaitonprefetch(ui, repo, **opts):
     return debugcommands.debugwaitonprefetch(repo)
 
 
 def resolveprefetchopts(ui, opts):
     if not opts.get(b'rev'):
         revset = [b'.', b'draft()']
 
         prefetchrevset = ui.config(b'remotefilelog', b'pullprefetch', None)
         if prefetchrevset:
             revset.append(b'(%s)' % prefetchrevset)
         bgprefetchrevs = ui.config(b'remotefilelog', b'bgprefetchrevs', None)
         if bgprefetchrevs:
             revset.append(b'(%s)' % bgprefetchrevs)
         revset = b'+'.join(revset)
 
         # update a revset with a date limit
         revset = revdatelimit(ui, revset)
 
         opts[b'rev'] = [revset]
 
     if not opts.get(b'base'):
         opts[b'base'] = None
 
     return opts
 
 
 @command(
     b'prefetch',
     [
         (b'r', b'rev', [], _(b'prefetch the specified revisions'), _(b'REV')),
         (b'', b'repack', False, _(b'run repack after prefetch')),
         (b'b', b'base', b'', _(b"rev that is assumed to already be local")),
     ]
     + commands.walkopts,
     _(b'hg prefetch [OPTIONS] [FILE...]'),
     helpcategory=command.CATEGORY_MAINTENANCE,
 )
 def prefetch(ui, repo, *pats, **opts):
     """prefetch file revisions from the server
 
     Prefetchs file revisions for the specified revs and stores them in the
     local remotefilelog cache.  If no rev is specified, the default rev is
     used which is the union of dot, draft, pullprefetch and bgprefetchrev.
     File names or patterns can be used to limit which files are downloaded.
 
     Return 0 on success.
     """
     opts = pycompat.byteskwargs(opts)
     if not isenabled(repo):
         raise error.Abort(_(b"repo is not shallow"))
 
     opts = resolveprefetchopts(ui, opts)
     revs = scmutil.revrange(repo, opts.get(b'rev'))
     repo.prefetch(revs, opts.get(b'base'), pats, opts)
 
     # Run repack in background
     if opts.get(b'repack'):
         repackmod.backgroundrepack(repo, incremental=True)
 
 
 @command(
     b'repack',
     [
         (b'', b'background', None, _(b'run in a background process'), None),
         (b'', b'incremental', None, _(b'do an incremental repack'), None),
         (
             b'',
             b'packsonly',
             None,
             _(b'only repack packs (skip loose objects)'),
             None,
         ),
     ],
     _(b'hg repack [OPTIONS]'),
 )
 def repack_(ui, repo, *pats, **opts):
     if opts.get('background'):
         repackmod.backgroundrepack(
             repo,
             incremental=opts.get('incremental'),
             packsonly=opts.get('packsonly', False),
         )
         return
 
     options = {b'packsonly': opts.get('packsonly')}
 
     try:
         if opts.get('incremental'):
             repackmod.incrementalrepack(repo, options=options)
         else:
             repackmod.fullrepack(repo, options=options)
     except repackmod.RepackAlreadyRunning as ex:
         # Don't propogate the exception if the repack is already in
         # progress, since we want the command to exit 0.
         repo.ui.warn(b'%s\n' % ex)

mercurial/cmdutil.py

@@ -1,4102 +1,3921
 # cmdutil.py - help for command processing in mercurial
 #
 # Copyright 2005-2007 Matt Mackall <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
 from __future__ import absolute_import
 
 import copy as copymod
 import errno
 import os
 import re
 
 from .i18n import _
 from .node import (
     hex,
     nullid,
-    nullrev,
     short,
 )
 from .pycompat import (
     getattr,
     open,
     setattr,
 )
 from .thirdparty import attr
 
 from . import (
     bookmarks,
     changelog,
     copies,
     crecord as crecordmod,
     dirstateguard,
     encoding,
     error,
     formatter,
     logcmdutil,
     match as matchmod,
     merge as mergemod,
     mergestate as mergestatemod,
     mergeutil,
     obsolete,
     patch,
     pathutil,
     phases,
     pycompat,
     repair,
     revlog,
     rewriteutil,
     scmutil,
-    smartset,
     state as statemod,
     subrepoutil,
     templatekw,
     templater,
     util,
     vfs as vfsmod,
 )
 
 from .utils import (
     dateutil,
     stringutil,
 )
 
 if pycompat.TYPE_CHECKING:
     from typing import (
         Any,
         Dict,
     )
 
     for t in (Any, Dict):
         assert t
 
 stringio = util.stringio
 
 # templates of common command options
 
 dryrunopts = [
     (b'n', b'dry-run', None, _(b'do not perform actions, just print output')),
 ]
 
 confirmopts = [
     (b'', b'confirm', None, _(b'ask before applying actions')),
 ]
 
 remoteopts = [
     (b'e', b'ssh', b'', _(b'specify ssh command to use'), _(b'CMD')),
     (
         b'',
         b'remotecmd',
         b'',
         _(b'specify hg command to run on the remote side'),
         _(b'CMD'),
     ),
     (
         b'',
         b'insecure',
         None,
         _(b'do not verify server certificate (ignoring web.cacerts config)'),
     ),
 ]
 
 walkopts = [
     (
         b'I',
         b'include',
         [],
         _(b'include names matching the given patterns'),
         _(b'PATTERN'),
     ),
     (
         b'X',
         b'exclude',
         [],
         _(b'exclude names matching the given patterns'),
         _(b'PATTERN'),
     ),
 ]
 
 commitopts = [
     (b'm', b'message', b'', _(b'use text as commit message'), _(b'TEXT')),
     (b'l', b'logfile', b'', _(b'read commit message from file'), _(b'FILE')),
 ]
 
 commitopts2 = [
     (
         b'd',
         b'date',
         b'',
         _(b'record the specified date as commit date'),
         _(b'DATE'),
     ),
     (
         b'u',
         b'user',
         b'',
         _(b'record the specified user as committer'),
         _(b'USER'),
     ),
 ]
 
 commitopts3 = [
     (b'D', b'currentdate', None, _(b'record the current date as commit date')),
     (b'U', b'currentuser', None, _(b'record the current user as committer')),
 ]
 
 formatteropts = [
     (b'T', b'template', b'', _(b'display with template'), _(b'TEMPLATE')),
 ]
 
 templateopts = [
     (
         b'',
         b'style',
         b'',
         _(b'display using template map file (DEPRECATED)'),
         _(b'STYLE'),
     ),
     (b'T', b'template', b'', _(b'display with template'), _(b'TEMPLATE')),
 ]
 
 logopts = [
     (b'p', b'patch', None, _(b'show patch')),
     (b'g', b'git', None, _(b'use git extended diff format')),
     (b'l', b'limit', b'', _(b'limit number of changes displayed'), _(b'NUM')),
     (b'M', b'no-merges', None, _(b'do not show merges')),
     (b'', b'stat', None, _(b'output diffstat-style summary of changes')),
     (b'G', b'graph', None, _(b"show the revision DAG")),
 ] + templateopts
 
 diffopts = [
     (b'a', b'text', None, _(b'treat all files as text')),
     (
         b'g',
         b'git',
         None,
         _(b'use git extended diff format (DEFAULT: diff.git)'),
     ),
     (b'', b'binary', None, _(b'generate binary diffs in git mode (default)')),
     (b'', b'nodates', None, _(b'omit dates from diff headers')),
 ]
 
 diffwsopts = [
     (
         b'w',
         b'ignore-all-space',
         None,
         _(b'ignore white space when comparing lines'),
     ),
     (
         b'b',
         b'ignore-space-change',
         None,
         _(b'ignore changes in the amount of white space'),
     ),
     (
         b'B',
         b'ignore-blank-lines',
         None,
         _(b'ignore changes whose lines are all blank'),
     ),
     (
         b'Z',
         b'ignore-space-at-eol',
         None,
         _(b'ignore changes in whitespace at EOL'),
     ),
 ]
 
 diffopts2 = (
     [
         (b'', b'noprefix', None, _(b'omit a/ and b/ prefixes from filenames')),
         (
             b'p',
             b'show-function',
             None,
             _(
                 b'show which function each change is in (DEFAULT: diff.showfunc)'
             ),
         ),
         (b'', b'reverse', None, _(b'produce a diff that undoes the changes')),
     ]
     + diffwsopts
     + [
         (
             b'U',
             b'unified',
             b'',
             _(b'number of lines of context to show'),
             _(b'NUM'),
         ),
         (b'', b'stat', None, _(b'output diffstat-style summary of changes')),
         (
             b'',
             b'root',
             b'',
             _(b'produce diffs relative to subdirectory'),
             _(b'DIR'),
         ),
     ]
 )
 
 mergetoolopts = [
     (b't', b'tool', b'', _(b'specify merge tool'), _(b'TOOL')),
 ]
 
 similarityopts = [
     (
         b's',
         b'similarity',
         b'',
         _(b'guess renamed files by similarity (0<=s<=100)'),
         _(b'SIMILARITY'),
     )
 ]
 
 subrepoopts = [(b'S', b'subrepos', None, _(b'recurse into subrepositories'))]
 
 debugrevlogopts = [
     (b'c', b'changelog', False, _(b'open changelog')),
     (b'm', b'manifest', False, _(b'open manifest')),
     (b'', b'dir', b'', _(b'open directory manifest')),
 ]
 
 # special string such that everything below this line will be ingored in the
 # editor text
 _linebelow = b"^HG: ------------------------ >8 ------------------------$"
 
 
 def check_at_most_one_arg(opts, *args):
     """abort if more than one of the arguments are in opts
 
     Returns the unique argument or None if none of them were specified.
     """
 
     def to_display(name):
         return pycompat.sysbytes(name).replace(b'_', b'-')
 
     previous = None
     for x in args:
         if opts.get(x):
             if previous:
                 raise error.Abort(
                     _(b'cannot specify both --%s and --%s')
                     % (to_display(previous), to_display(x))
                 )
             previous = x
     return previous
 
 
 def check_incompatible_arguments(opts, first, others):
     """abort if the first argument is given along with any of the others
 
     Unlike check_at_most_one_arg(), `others` are not mutually exclusive
     among themselves, and they're passed as a single collection.
     """
     for other in others:
         check_at_most_one_arg(opts, first, other)
 
 
 def resolvecommitoptions(ui, opts):
     """modify commit options dict to handle related options
 
     The return value indicates that ``rewrite.update-timestamp`` is the reason
     the ``date`` option is set.
     """
     check_at_most_one_arg(opts, b'date', b'currentdate')
     check_at_most_one_arg(opts, b'user', b'currentuser')
 
     datemaydiffer = False  # date-only change should be ignored?
 
     if opts.get(b'currentdate'):
         opts[b'date'] = b'%d %d' % dateutil.makedate()
     elif (
         not opts.get(b'date')
         and ui.configbool(b'rewrite', b'update-timestamp')
         and opts.get(b'currentdate') is None
     ):
         opts[b'date'] = b'%d %d' % dateutil.makedate()
         datemaydiffer = True
 
     if opts.get(b'currentuser'):
         opts[b'user'] = ui.username()
 
     return datemaydiffer
 
 
 def checknotesize(ui, opts):
     """ make sure note is of valid format """
 
     note = opts.get(b'note')
     if not note:
         return
 
     if len(note) > 255:
         raise error.Abort(_(b"cannot store a note of more than 255 bytes"))
     if b'\n' in note:
         raise error.Abort(_(b"note cannot contain a newline"))
 
 
 def ishunk(x):
     hunkclasses = (crecordmod.uihunk, patch.recordhunk)
     return isinstance(x, hunkclasses)
 
 
 def newandmodified(chunks, originalchunks):
     newlyaddedandmodifiedfiles = set()
     alsorestore = set()
     for chunk in chunks:
         if (
             ishunk(chunk)
             and chunk.header.isnewfile()
             and chunk not in originalchunks
         ):
             newlyaddedandmodifiedfiles.add(chunk.header.filename())
             alsorestore.update(
                 set(chunk.header.files()) - {chunk.header.filename()}
             )
     return newlyaddedandmodifiedfiles, alsorestore
 
 
 def parsealiases(cmd):
     return cmd.split(b"|")
 
 
 def setupwrapcolorwrite(ui):
     # wrap ui.write so diff output can be labeled/colorized
     def wrapwrite(orig, *args, **kw):
         label = kw.pop('label', b'')
         for chunk, l in patch.difflabel(lambda: args):
             orig(chunk, label=label + l)
 
     oldwrite = ui.write
 
     def wrap(*args, **kwargs):
         return wrapwrite(oldwrite, *args, **kwargs)
 
     setattr(ui, 'write', wrap)
     return oldwrite
 
 
 def filterchunks(ui, originalhunks, usecurses, testfile, match, operation=None):
     try:
         if usecurses:
             if testfile:
                 recordfn = crecordmod.testdecorator(
                     testfile, crecordmod.testchunkselector
                 )
             else:
                 recordfn = crecordmod.chunkselector
 
             return crecordmod.filterpatch(
                 ui, originalhunks, recordfn, operation
             )
     except crecordmod.fallbackerror as e:
         ui.warn(b'%s\n' % e)
         ui.warn(_(b'falling back to text mode\n'))
 
     return patch.filterpatch(ui, originalhunks, match, operation)
 
 
 def recordfilter(ui, originalhunks, match, operation=None):
     """ Prompts the user to filter the originalhunks and return a list of
     selected hunks.
     *operation* is used for to build ui messages to indicate the user what
     kind of filtering they are doing: reverting, committing, shelving, etc.
     (see patch.filterpatch).
     """
     usecurses = crecordmod.checkcurses(ui)
     testfile = ui.config(b'experimental', b'crecordtest')
     oldwrite = setupwrapcolorwrite(ui)
     try:
         newchunks, newopts = filterchunks(
             ui, originalhunks, usecurses, testfile, match, operation
         )
     finally:
         ui.write = oldwrite
     return newchunks, newopts
 
 
 def dorecord(
     ui, repo, commitfunc, cmdsuggest, backupall, filterfn, *pats, **opts
 ):
     opts = pycompat.byteskwargs(opts)
     if not ui.interactive():
         if cmdsuggest:
             msg = _(b'running non-interactively, use %s instead') % cmdsuggest
         else:
             msg = _(b'running non-interactively')
         raise error.Abort(msg)
 
     # make sure username is set before going interactive
     if not opts.get(b'user'):
         ui.username()  # raise exception, username not provided
 
     def recordfunc(ui, repo, message, match, opts):
         """This is generic record driver.
 
         Its job is to interactively filter local changes, and
         accordingly prepare working directory into a state in which the
         job can be delegated to a non-interactive commit command such as
         'commit' or 'qrefresh'.
 
         After the actual job is done by non-interactive command, the
         working directory is restored to its original state.
 
         In the end we'll record interesting changes, and everything else
         will be left in place, so the user can continue working.
         """
         if not opts.get(b'interactive-unshelve'):
             checkunfinished(repo, commit=True)
         wctx = repo[None]
         merge = len(wctx.parents()) > 1
         if merge:
             raise error.Abort(
                 _(
                     b'cannot partially commit a merge '
                     b'(use "hg commit" instead)'
                 )
             )
 
         def fail(f, msg):
             raise error.Abort(b'%s: %s' % (f, msg))
 
         force = opts.get(b'force')
         if not force:
             match = matchmod.badmatch(match, fail)
 
         status = repo.status(match=match)
 
         overrides = {(b'ui', b'commitsubrepos'): True}
 
         with repo.ui.configoverride(overrides, b'record'):
             # subrepoutil.precommit() modifies the status
             tmpstatus = scmutil.status(
                 copymod.copy(status.modified),
                 copymod.copy(status.added),
                 copymod.copy(status.removed),
                 copymod.copy(status.deleted),
                 copymod.copy(status.unknown),
                 copymod.copy(status.ignored),
                 copymod.copy(status.clean),  # pytype: disable=wrong-arg-count
             )
 
             # Force allows -X subrepo to skip the subrepo.
             subs, commitsubs, newstate = subrepoutil.precommit(
                 repo.ui, wctx, tmpstatus, match, force=True
             )
             for s in subs:
                 if s in commitsubs:
                     dirtyreason = wctx.sub(s).dirtyreason(True)
                     raise error.Abort(dirtyreason)
 
         if not force:
             repo.checkcommitpatterns(wctx, match, status, fail)
         diffopts = patch.difffeatureopts(
             ui,
             opts=opts,
             whitespace=True,
             section=b'commands',
             configprefix=b'commit.interactive.',
         )
         diffopts.nodates = True
         diffopts.git = True
         diffopts.showfunc = True
         originaldiff = patch.diff(repo, changes=status, opts=diffopts)
         originalchunks = patch.parsepatch(originaldiff)
         match = scmutil.match(repo[None], pats)
 
         # 1. filter patch, since we are intending to apply subset of it
         try:
             chunks, newopts = filterfn(ui, originalchunks, match)
         except error.PatchError as err:
             raise error.Abort(_(b'error parsing patch: %s') % err)
         opts.update(newopts)
 
         # We need to keep a backup of files that have been newly added and
         # modified during the recording process because there is a previous
         # version without the edit in the workdir. We also will need to restore
         # files that were the sources of renames so that the patch application
         # works.
         newlyaddedandmodifiedfiles, alsorestore = newandmodified(
             chunks, originalchunks
         )
         contenders = set()
         for h in chunks:
             try:
                 contenders.update(set(h.files()))
             except AttributeError:
                 pass
 
         changed = status.modified + status.added + status.removed
         newfiles = [f for f in changed if f in contenders]
         if not newfiles:
             ui.status(_(b'no changes to record\n'))
             return 0
 
         modified = set(status.modified)
 
         # 2. backup changed files, so we can restore them in the end
 
         if backupall:
             tobackup = changed
         else:
             tobackup = [
                 f
                 for f in newfiles
                 if f in modified or f in newlyaddedandmodifiedfiles
             ]
         backups = {}
         if tobackup:
             backupdir = repo.vfs.join(b'record-backups')
             try:
                 os.mkdir(backupdir)
             except OSError as err:
                 if err.errno != errno.EEXIST:
                     raise
         try:
             # backup continues
             for f in tobackup:
                 fd, tmpname = pycompat.mkstemp(
                     prefix=f.replace(b'/', b'_') + b'.', dir=backupdir
                 )
                 os.close(fd)
                 ui.debug(b'backup %r as %r\n' % (f, tmpname))
                 util.copyfile(repo.wjoin(f), tmpname, copystat=True)
                 backups[f] = tmpname
 
             fp = stringio()
             for c in chunks:
                 fname = c.filename()
                 if fname in backups:
                     c.write(fp)
             dopatch = fp.tell()
             fp.seek(0)
 
             # 2.5 optionally review / modify patch in text editor
             if opts.get(b'review', False):
                 patchtext = (
                     crecordmod.diffhelptext
                     + crecordmod.patchhelptext
                     + fp.read()
                 )
                 reviewedpatch = ui.edit(
                     patchtext, b"", action=b"diff", repopath=repo.path
                 )
                 fp.truncate(0)
                 fp.write(reviewedpatch)
                 fp.seek(0)
 
             [os.unlink(repo.wjoin(c)) for c in newlyaddedandmodifiedfiles]
             # 3a. apply filtered patch to clean repo  (clean)
             if backups:
                 m = scmutil.matchfiles(repo, set(backups.keys()) | alsorestore)
                 mergemod.revert_to(repo[b'.'], matcher=m)
 
             # 3b. (apply)
             if dopatch:
                 try:
                     ui.debug(b'applying patch\n')
                     ui.debug(fp.getvalue())
                     patch.internalpatch(ui, repo, fp, 1, eolmode=None)
                 except error.PatchError as err:
                     raise error.Abort(pycompat.bytestr(err))
             del fp
 
             # 4. We prepared working directory according to filtered
             #    patch. Now is the time to delegate the job to
             #    commit/qrefresh or the like!
 
             # Make all of the pathnames absolute.
             newfiles = [repo.wjoin(nf) for nf in newfiles]
             return commitfunc(ui, repo, *newfiles, **pycompat.strkwargs(opts))
         finally:
             # 5. finally restore backed-up files
             try:
                 dirstate = repo.dirstate
                 for realname, tmpname in pycompat.iteritems(backups):
                     ui.debug(b'restoring %r to %r\n' % (tmpname, realname))
 
                     if dirstate[realname] == b'n':
                         # without normallookup, restoring timestamp
                         # may cause partially committed files
                         # to be treated as unmodified
                         dirstate.normallookup(realname)
 
                     # copystat=True here and above are a hack to trick any
                     # editors that have f open that we haven't modified them.
                     #
                     # Also note that this racy as an editor could notice the
                     # file's mtime before we've finished writing it.
                     util.copyfile(tmpname, repo.wjoin(realname), copystat=True)
                     os.unlink(tmpname)
                 if tobackup:
                     os.rmdir(backupdir)
             except OSError:
                 pass
 
     def recordinwlock(ui, repo, message, match, opts):
         with repo.wlock():
             return recordfunc(ui, repo, message, match, opts)
 
     return commit(ui, repo, recordinwlock, pats, opts)
 
 
 class dirnode(object):
     """
     Represent a directory in user working copy with information required for
     the purpose of tersing its status.
 
     path is the path to the directory, without a trailing '/'
 
     statuses is a set of statuses of all files in this directory (this includes
     all the files in all the subdirectories too)
 
     files is a list of files which are direct child of this directory
 
     subdirs is a dictionary of sub-directory name as the key and it's own
     dirnode object as the value
     """
 
     def __init__(self, dirpath):
         self.path = dirpath
         self.statuses = set()
         self.files = []
         self.subdirs = {}
 
     def _addfileindir(self, filename, status):
         """Add a file in this directory as a direct child."""
         self.files.append((filename, status))
 
     def addfile(self, filename, status):
         """
         Add a file to this directory or to its direct parent directory.
 
         If the file is not direct child of this directory, we traverse to the
         directory of which this file is a direct child of and add the file
         there.
         """
 
         # the filename contains a path separator, it means it's not the direct
         # child of this directory
         if b'/' in filename:
             subdir, filep = filename.split(b'/', 1)
 
             # does the dirnode object for subdir exists
             if subdir not in self.subdirs:
                 subdirpath = pathutil.join(self.path, subdir)
                 self.subdirs[subdir] = dirnode(subdirpath)
 
             # try adding the file in subdir
             self.subdirs[subdir].addfile(filep, status)
 
         else:
             self._addfileindir(filename, status)
 
         if status not in self.statuses:
             self.statuses.add(status)
 
     def iterfilepaths(self):
         """Yield (status, path) for files directly under this directory."""
         for f, st in self.files:
             yield st, pathutil.join(self.path, f)
 
     def tersewalk(self, terseargs):
         """
         Yield (status, path) obtained by processing the status of this
         dirnode.
 
         terseargs is the string of arguments passed by the user with `--terse`
         flag.
 
         Following are the cases which can happen:
 
         1) All the files in the directory (including all the files in its
         subdirectories) share the same status and the user has asked us to terse
         that status. -> yield (status, dirpath).  dirpath will end in '/'.
 
         2) Otherwise, we do following:
 
                 a) Yield (status, filepath)  for all the files which are in this
                     directory (only the ones in this directory, not the subdirs)
 
                 b) Recurse the function on all the subdirectories of this
                    directory
         """
 
         if len(self.statuses) == 1:
             onlyst = self.statuses.pop()
 
             # Making sure we terse only when the status abbreviation is
             # passed as terse argument
             if onlyst in terseargs:
                 yield onlyst, self.path + b'/'
                 return
 
         # add the files to status list
         for st, fpath in self.iterfilepaths():
             yield st, fpath
 
         # recurse on the subdirs
         for dirobj in self.subdirs.values():
             for st, fpath in dirobj.tersewalk(terseargs):
                 yield st, fpath
 
 
 def tersedir(statuslist, terseargs):
     """
     Terse the status if all the files in a directory shares the same status.
 
     statuslist is scmutil.status() object which contains a list of files for
     each status.
     terseargs is string which is passed by the user as the argument to `--terse`
     flag.
 
     The function makes a tree of objects of dirnode class, and at each node it
     stores the information required to know whether we can terse a certain
     directory or not.
     """
     # the order matters here as that is used to produce final list
     allst = (b'm', b'a', b'r', b'd', b'u', b'i', b'c')
 
     # checking the argument validity
     for s in pycompat.bytestr(terseargs):
         if s not in allst:
             raise error.Abort(_(b"'%s' not recognized") % s)
 
     # creating a dirnode object for the root of the repo
     rootobj = dirnode(b'')
     pstatus = (
         b'modified',
         b'added',
         b'deleted',
         b'clean',
         b'unknown',
         b'ignored',
         b'removed',
     )
 
     tersedict = {}
     for attrname in pstatus:
         statuschar = attrname[0:1]
         for f in getattr(statuslist, attrname):
             rootobj.addfile(f, statuschar)
         tersedict[statuschar] = []
 
     # we won't be tersing the root dir, so add files in it
     for st, fpath in rootobj.iterfilepaths():
         tersedict[st].append(fpath)
 
     # process each sub-directory and build tersedict
     for subdir in rootobj.subdirs.values():
         for st, f in subdir.tersewalk(terseargs):
             tersedict[st].append(f)
 
     tersedlist = []
     for st in allst:
         tersedict[st].sort()
         tersedlist.append(tersedict[st])
 
     return scmutil.status(*tersedlist)
 
 
 def _commentlines(raw):
     '''Surround lineswith a comment char and a new line'''
     lines = raw.splitlines()
     commentedlines = [b'# %s' % line for line in lines]
     return b'\n'.join(commentedlines) + b'\n'
 
 
 @attr.s(frozen=True)
 class morestatus(object):
     reporoot = attr.ib()
     unfinishedop = attr.ib()
     unfinishedmsg = attr.ib()
     activemerge = attr.ib()
     unresolvedpaths = attr.ib()
     _formattedpaths = attr.ib(init=False, default=set())
     _label = b'status.morestatus'
 
     def formatfile(self, path, fm):
         self._formattedpaths.add(path)
         if self.activemerge and path in self.unresolvedpaths:
             fm.data(unresolved=True)
 
     def formatfooter(self, fm):
         if self.unfinishedop or self.unfinishedmsg:
             fm.startitem()
             fm.data(itemtype=b'morestatus')
 
         if self.unfinishedop:
             fm.data(unfinished=self.unfinishedop)
             statemsg = (
                 _(b'The repository is in an unfinished *%s* state.')
                 % self.unfinishedop
             )
             fm.plain(b'%s\n' % _commentlines(statemsg), label=self._label)
         if self.unfinishedmsg:
             fm.data(unfinishedmsg=self.unfinishedmsg)
 
         # May also start new data items.
         self._formatconflicts(fm)
 
         if self.unfinishedmsg:
             fm.plain(
                 b'%s\n' % _commentlines(self.unfinishedmsg), label=self._label
             )
 
     def _formatconflicts(self, fm):
         if not self.activemerge:
             return
 
         if self.unresolvedpaths:
             mergeliststr = b'\n'.join(
                 [
                     b'    %s'
                     % util.pathto(self.reporoot, encoding.getcwd(), path)
                     for path in self.unresolvedpaths
                 ]
             )
             msg = (
                 _(
                     '''Unresolved merge conflicts:
 
 %s
 
 To mark files as resolved:  hg resolve --mark FILE'''
                 )
                 % mergeliststr
             )
 
             # If any paths with unresolved conflicts were not previously
             # formatted, output them now.
             for f in self.unresolvedpaths:
                 if f in self._formattedpaths:
                     # Already output.
                     continue
                 fm.startitem()
                 # We can't claim to know the status of the file - it may just
                 # have been in one of the states that were not requested for
                 # display, so it could be anything.
                 fm.data(itemtype=b'file', path=f, unresolved=True)
 
         else:
             msg = _(b'No unresolved merge conflicts.')
 
         fm.plain(b'%s\n' % _commentlines(msg), label=self._label)
 
 
 def readmorestatus(repo):
     """Returns a morestatus object if the repo has unfinished state."""
     statetuple = statemod.getrepostate(repo)
     mergestate = mergestatemod.mergestate.read(repo)
     activemerge = mergestate.active()
     if not statetuple and not activemerge:
         return None
 
     unfinishedop = unfinishedmsg = unresolved = None
     if statetuple:
         unfinishedop, unfinishedmsg = statetuple
     if activemerge:
         unresolved = sorted(mergestate.unresolved())
     return morestatus(
         repo.root, unfinishedop, unfinishedmsg, activemerge, unresolved
     )
 
 
 def findpossible(cmd, table, strict=False):
     """
     Return cmd -> (aliases, command table entry)
     for each matching command.
     Return debug commands (or their aliases) only if no normal command matches.
     """
     choice = {}
     debugchoice = {}
 
     if cmd in table:
         # short-circuit exact matches, "log" alias beats "log|history"
         keys = [cmd]
     else:
         keys = table.keys()
 
     allcmds = []
     for e in keys:
         aliases = parsealiases(e)
         allcmds.extend(aliases)
         found = None
         if cmd in aliases:
             found = cmd
         elif not strict:
             for a in aliases:
                 if a.startswith(cmd):
                     found = a
                     break
         if found is not None:
             if aliases[0].startswith(b"debug") or found.startswith(b"debug"):
                 debugchoice[found] = (aliases, table[e])
             else:
                 choice[found] = (aliases, table[e])
 
     if not choice and debugchoice:
         choice = debugchoice
 
     return choice, allcmds
 
 
 def findcmd(cmd, table, strict=True):
     """Return (aliases, command table entry) for command string."""
     choice, allcmds = findpossible(cmd, table, strict)
 
     if cmd in choice:
         return choice[cmd]
 
     if len(choice) > 1:
         clist = sorted(choice)
         raise error.AmbiguousCommand(cmd, clist)
 
     if choice:
         return list(choice.values())[0]
 
     raise error.UnknownCommand(cmd, allcmds)
 
 
 def changebranch(ui, repo, revs, label, opts):
     """ Change the branch name of given revs to label """
 
     with repo.wlock(), repo.lock(), repo.transaction(b'branches'):
         # abort in case of uncommitted merge or dirty wdir
         bailifchanged(repo)
         revs = scmutil.revrange(repo, revs)
         if not revs:
             raise error.Abort(b"empty revision set")
         roots = repo.revs(b'roots(%ld)', revs)
         if len(roots) > 1:
             raise error.Abort(
                 _(b"cannot change branch of non-linear revisions")
             )
         rewriteutil.precheck(repo, revs, b'change branch of')
 
         root = repo[roots.first()]
         rpb = {parent.branch() for parent in root.parents()}
         if (
             not opts.get(b'force')
             and label not in rpb
             and label in repo.branchmap()
         ):
             raise error.Abort(_(b"a branch of the same name already exists"))
 
         if repo.revs(b'obsolete() and %ld', revs):
             raise error.Abort(
                 _(b"cannot change branch of a obsolete changeset")
             )
 
         # make sure only topological heads
         if repo.revs(b'heads(%ld) - head()', revs):
             raise error.Abort(_(b"cannot change branch in middle of a stack"))
 
         replacements = {}
         # avoid import cycle mercurial.cmdutil -> mercurial.context ->
         # mercurial.subrepo -> mercurial.cmdutil
         from . import context
 
         for rev in revs:
             ctx = repo[rev]
             oldbranch = ctx.branch()
             # check if ctx has same branch
             if oldbranch == label:
                 continue
 
             def filectxfn(repo, newctx, path):
                 try:
                     return ctx[path]
                 except error.ManifestLookupError:
                     return None
 
             ui.debug(
                 b"changing branch of '%s' from '%s' to '%s'\n"
                 % (hex(ctx.node()), oldbranch, label)
             )
             extra = ctx.extra()
             extra[b'branch_change'] = hex(ctx.node())
             # While changing branch of set of linear commits, make sure that
             # we base our commits on new parent rather than old parent which
             # was obsoleted while changing the branch
             p1 = ctx.p1().node()
             p2 = ctx.p2().node()
             if p1 in replacements:
                 p1 = replacements[p1][0]
             if p2 in replacements:
                 p2 = replacements[p2][0]
 
             mc = context.memctx(
                 repo,
                 (p1, p2),
                 ctx.description(),
                 ctx.files(),
                 filectxfn,
                 user=ctx.user(),
                 date=ctx.date(),
                 extra=extra,
                 branch=label,
             )
 
             newnode = repo.commitctx(mc)
             replacements[ctx.node()] = (newnode,)
             ui.debug(b'new node id is %s\n' % hex(newnode))
 
         # create obsmarkers and move bookmarks
         scmutil.cleanupnodes(
             repo, replacements, b'branch-change', fixphase=True
         )
 
         # move the working copy too
         wctx = repo[None]
         # in-progress merge is a bit too complex for now.
         if len(wctx.parents()) == 1:
             newid = replacements.get(wctx.p1().node())
             if newid is not None:
                 # avoid import cycle mercurial.cmdutil -> mercurial.hg ->
                 # mercurial.cmdutil
                 from . import hg
 
                 hg.update(repo, newid[0], quietempty=True)
 
         ui.status(_(b"changed branch on %d changesets\n") % len(replacements))
 
 
 def findrepo(p):
     while not os.path.isdir(os.path.join(p, b".hg")):
         oldp, p = p, os.path.dirname(p)
         if p == oldp:
             return None
 
     return p
 
 
 def bailifchanged(repo, merge=True, hint=None):
     """ enforce the precondition that working directory must be clean.
 
     'merge' can be set to false if a pending uncommitted merge should be
     ignored (such as when 'update --check' runs).
 
     'hint' is the usual hint given to Abort exception.
     """
 
     if merge and repo.dirstate.p2() != nullid:
         raise error.Abort(_(b'outstanding uncommitted merge'), hint=hint)
     st = repo.status()
     if st.modified or st.added or st.removed or st.deleted:
         raise error.Abort(_(b'uncommitted changes'), hint=hint)
     ctx = repo[None]
     for s in sorted(ctx.substate):
         ctx.sub(s).bailifchanged(hint=hint)
 
 
 def logmessage(ui, opts):
     """ get the log message according to -m and -l option """
 
     check_at_most_one_arg(opts, b'message', b'logfile')
 
     message = opts.get(b'message')
     logfile = opts.get(b'logfile')
 
     if not message and logfile:
         try:
             if isstdiofilename(logfile):
                 message = ui.fin.read()
             else:
                 message = b'\n'.join(util.readfile(logfile).splitlines())
         except IOError as inst:
             raise error.Abort(
                 _(b"can't read commit message '%s': %s")
                 % (logfile, encoding.strtolocal(inst.strerror))
             )
     return message
 
 
 def mergeeditform(ctxorbool, baseformname):
     """return appropriate editform name (referencing a committemplate)
 
     'ctxorbool' is either a ctx to be committed, or a bool indicating whether
     merging is committed.
 
     This returns baseformname with '.merge' appended if it is a merge,
     otherwise '.normal' is appended.
     """
     if isinstance(ctxorbool, bool):
         if ctxorbool:
             return baseformname + b".merge"
     elif len(ctxorbool.parents()) > 1:
         return baseformname + b".merge"
 
     return baseformname + b".normal"
 
 
 def getcommiteditor(
     edit=False, finishdesc=None, extramsg=None, editform=b'', **opts
 ):
     """get appropriate commit message editor according to '--edit' option
 
     'finishdesc' is a function to be called with edited commit message
     (= 'description' of the new changeset) just after editing, but
     before checking empty-ness. It should return actual text to be
     stored into history. This allows to change description before
     storing.
 
     'extramsg' is a extra message to be shown in the editor instead of
     'Leave message empty to abort commit' line. 'HG: ' prefix and EOL
     is automatically added.
 
     'editform' is a dot-separated list of names, to distinguish
     the purpose of commit text editing.
 
     'getcommiteditor' returns 'commitforceeditor' regardless of
     'edit', if one of 'finishdesc' or 'extramsg' is specified, because
     they are specific for usage in MQ.
     """
     if edit or finishdesc or extramsg:
         return lambda r, c, s: commitforceeditor(
             r, c, s, finishdesc=finishdesc, extramsg=extramsg, editform=editform
         )
     elif editform:
         return lambda r, c, s: commiteditor(r, c, s, editform=editform)
     else:
         return commiteditor
 
 
 def _escapecommandtemplate(tmpl):
     parts = []
     for typ, start, end in templater.scantemplate(tmpl, raw=True):
         if typ == b'string':
             parts.append(stringutil.escapestr(tmpl[start:end]))
         else:
             parts.append(tmpl[start:end])
     return b''.join(parts)
 
 
 def rendercommandtemplate(ui, tmpl, props):
     r"""Expand a literal template 'tmpl' in a way suitable for command line
 
     '\' in outermost string is not taken as an escape character because it
     is a directory separator on Windows.
 
     >>> from . import ui as uimod
     >>> ui = uimod.ui()
     >>> rendercommandtemplate(ui, b'c:\\{path}', {b'path': b'foo'})
     'c:\\foo'
     >>> rendercommandtemplate(ui, b'{"c:\\{path}"}', {'path': b'foo'})
     'c:{path}'
     """
     if not tmpl:
         return tmpl
     t = formatter.maketemplater(ui, _escapecommandtemplate(tmpl))
     return t.renderdefault(props)
 
 
 def rendertemplate(ctx, tmpl, props=None):
     """Expand a literal template 'tmpl' byte-string against one changeset
 
     Each props item must be a stringify-able value or a callable returning
     such value, i.e. no bare list nor dict should be passed.
     """
     repo = ctx.repo()
     tres = formatter.templateresources(repo.ui, repo)
     t = formatter.maketemplater(
         repo.ui, tmpl, defaults=templatekw.keywords, resources=tres
     )
     mapping = {b'ctx': ctx}
     if props:
         mapping.update(props)
     return t.renderdefault(mapping)
 
 
 def _buildfntemplate(pat, total=None, seqno=None, revwidth=None, pathname=None):
     r"""Convert old-style filename format string to template string
 
     >>> _buildfntemplate(b'foo-%b-%n.patch', seqno=0)
     'foo-{reporoot|basename}-{seqno}.patch'
     >>> _buildfntemplate(b'%R{tags % "{tag}"}%H')
     '{rev}{tags % "{tag}"}{node}'
 
     '\' in outermost strings has to be escaped because it is a directory
     separator on Windows:
 
     >>> _buildfntemplate(b'c:\\tmp\\%R\\%n.patch', seqno=0)
     'c:\\\\tmp\\\\{rev}\\\\{seqno}.patch'
     >>> _buildfntemplate(b'\\\\foo\\bar.patch')
     '\\\\\\\\foo\\\\bar.patch'
     >>> _buildfntemplate(b'\\{tags % "{tag}"}')
     '\\\\{tags % "{tag}"}'
 
     but inner strings follow the template rules (i.e. '\' is taken as an
     escape character):
 
     >>> _buildfntemplate(br'{"c:\tmp"}', seqno=0)
     '{"c:\\tmp"}'
     """
     expander = {
         b'H': b'{node}',
         b'R': b'{rev}',
         b'h': b'{node|short}',
         b'm': br'{sub(r"[^\w]", "_", desc|firstline)}',
         b'r': b'{if(revwidth, pad(rev, revwidth, "0", left=True), rev)}',
         b'%': b'%',
         b'b': b'{reporoot|basename}',
     }
     if total is not None:
         expander[b'N'] = b'{total}'
     if seqno is not None:
         expander[b'n'] = b'{seqno}'
     if total is not None and seqno is not None:
         expander[b'n'] = b'{pad(seqno, total|stringify|count, "0", left=True)}'
     if pathname is not None:
         expander[b's'] = b'{pathname|basename}'
         expander[b'd'] = b'{if(pathname|dirname, pathname|dirname, ".")}'
         expander[b'p'] = b'{pathname}'
 
     newname = []
     for typ, start, end in templater.scantemplate(pat, raw=True):
         if typ != b'string':
             newname.append(pat[start:end])
             continue
         i = start
         while i < end:
             n = pat.find(b'%', i, end)
             if n < 0:
                 newname.append(stringutil.escapestr(pat[i:end]))
                 break
             newname.append(stringutil.escapestr(pat[i:n]))
             if n + 2 > end:
                 raise error.Abort(
                     _(b"incomplete format spec in output filename")
                 )
             c = pat[n + 1 : n + 2]
             i = n + 2
             try:
                 newname.append(expander[c])
             except KeyError:
                 raise error.Abort(
                     _(b"invalid format spec '%%%s' in output filename") % c
                 )
     return b''.join(newname)
 
 
 def makefilename(ctx, pat, **props):
     if not pat:
         return pat
     tmpl = _buildfntemplate(pat, **props)
     # BUG: alias expansion shouldn't be made against template fragments
     # rewritten from %-format strings, but we have no easy way to partially
     # disable the expansion.
     return rendertemplate(ctx, tmpl, pycompat.byteskwargs(props))
 
 
 def isstdiofilename(pat):
     """True if the given pat looks like a filename denoting stdin/stdout"""
     return not pat or pat == b'-'
 
 
 class _unclosablefile(object):
     def __init__(self, fp):
         self._fp = fp
 
     def close(self):
         pass
 
     def __iter__(self):
         return iter(self._fp)
 
     def __getattr__(self, attr):
         return getattr(self._fp, attr)
 
     def __enter__(self):
         return self
 
     def __exit__(self, exc_type, exc_value, exc_tb):
         pass
 
 
 def makefileobj(ctx, pat, mode=b'wb', **props):
     writable = mode not in (b'r', b'rb')
 
     if isstdiofilename(pat):
         repo = ctx.repo()
         if writable:
             fp = repo.ui.fout
         else:
             fp = repo.ui.fin
         return _unclosablefile(fp)
     fn = makefilename(ctx, pat, **props)
     return open(fn, mode)
 
 
 def openstorage(repo, cmd, file_, opts, returnrevlog=False):
     """opens the changelog, manifest, a filelog or a given revlog"""
     cl = opts[b'changelog']
     mf = opts[b'manifest']
     dir = opts[b'dir']
     msg = None
     if cl and mf:
         msg = _(b'cannot specify --changelog and --manifest at the same time')
     elif cl and dir:
         msg = _(b'cannot specify --changelog and --dir at the same time')
     elif cl or mf or dir:
         if file_:
             msg = _(b'cannot specify filename with --changelog or --manifest')
         elif not repo:
             msg = _(
                 b'cannot specify --changelog or --manifest or --dir '
                 b'without a repository'
             )
     if msg:
         raise error.Abort(msg)
 
     r = None
     if repo:
         if cl:
             r = repo.unfiltered().changelog
         elif dir:
             if not scmutil.istreemanifest(repo):
                 raise error.Abort(
                     _(
                         b"--dir can only be used on repos with "
                         b"treemanifest enabled"
                     )
                 )
             if not dir.endswith(b'/'):
                 dir = dir + b'/'
             dirlog = repo.manifestlog.getstorage(dir)
             if len(dirlog):
                 r = dirlog
         elif mf:
             r = repo.manifestlog.getstorage(b'')
         elif file_:
             filelog = repo.file(file_)
             if len(filelog):
                 r = filelog
 
         # Not all storage may be revlogs. If requested, try to return an actual
         # revlog instance.
         if returnrevlog:
             if isinstance(r, revlog.revlog):
                 pass
             elif util.safehasattr(r, b'_revlog'):
                 r = r._revlog  # pytype: disable=attribute-error
             elif r is not None:
                 raise error.Abort(_(b'%r does not appear to be a revlog') % r)
 
     if not r:
         if not returnrevlog:
             raise error.Abort(_(b'cannot give path to non-revlog'))
 
         if not file_:
             raise error.CommandError(cmd, _(b'invalid arguments'))
         if not os.path.isfile(file_):
             raise error.Abort(_(b"revlog '%s' not found") % file_)
         r = revlog.revlog(
             vfsmod.vfs(encoding.getcwd(), audit=False), file_[:-2] + b".i"
         )
     return r
 
 
 def openrevlog(repo, cmd, file_, opts):
     """Obtain a revlog backing storage of an item.
 
     This is similar to ``openstorage()`` except it always returns a revlog.
 
     In most cases, a caller cares about the main storage object - not the
     revlog backing it. Therefore, this function should only be used by code
     that needs to examine low-level revlog implementation details. e.g. debug
     commands.
     """
     return openstorage(repo, cmd, file_, opts, returnrevlog=True)
 
 
 def copy(ui, repo, pats, opts, rename=False):
     check_incompatible_arguments(opts, b'forget', [b'dry_run'])
 
     # called with the repo lock held
     #
     # hgsep => pathname that uses "/" to separate directories
     # ossep => pathname that uses os.sep to separate directories
     cwd = repo.getcwd()
     targets = {}
     forget = opts.get(b"forget")
     after = opts.get(b"after")
     dryrun = opts.get(b"dry_run")
     rev = opts.get(b'at_rev')
     if rev:
         if not forget and not after:
             # TODO: Remove this restriction and make it also create the copy
             #       targets (and remove the rename source if rename==True).
             raise error.Abort(_(b'--at-rev requires --after'))
         ctx = scmutil.revsingle(repo, rev)
         if len(ctx.parents()) > 1:
             raise error.Abort(_(b'cannot mark/unmark copy in merge commit'))
     else:
         ctx = repo[None]
 
     pctx = ctx.p1()
 
     uipathfn = scmutil.getuipathfn(repo, legacyrelativevalue=True)
 
     if forget:
         if ctx.rev() is None:
             new_ctx = ctx
         else:
             if len(ctx.parents()) > 1:
                 raise error.Abort(_(b'cannot unmark copy in merge commit'))
             # avoid cycle context -> subrepo -> cmdutil
             from . import context
 
             rewriteutil.precheck(repo, [ctx.rev()], b'uncopy')
             new_ctx = context.overlayworkingctx(repo)
             new_ctx.setbase(ctx.p1())
             mergemod.graft(repo, ctx, wctx=new_ctx)
 
         match = scmutil.match(ctx, pats, opts)
 
         current_copies = ctx.p1copies()
         current_copies.update(ctx.p2copies())
 
         uipathfn = scmutil.getuipathfn(repo)
         for f in ctx.walk(match):
             if f in current_copies:
                 new_ctx[f].markcopied(None)
             elif match.exact(f):
                 ui.warn(
                     _(
                         b'%s: not unmarking as copy - file is not marked as copied\n'
                     )
                     % uipathfn(f)
                 )
 
         if ctx.rev() is not None:
             with repo.lock():
                 mem_ctx = new_ctx.tomemctx_for_amend(ctx)
                 new_node = mem_ctx.commit()
 
                 if repo.dirstate.p1() == ctx.node():
                     with repo.dirstate.parentchange():
                         scmutil.movedirstate(repo, repo[new_node])
                 replacements = {ctx.node(): [new_node]}
                 scmutil.cleanupnodes(
                     repo, replacements, b'uncopy', fixphase=True
                 )
 
         return
 
     pats = scmutil.expandpats(pats)
     if not pats:
         raise error.Abort(_(b'no source or destination specified'))
     if len(pats) == 1:
         raise error.Abort(_(b'no destination specified'))
     dest = pats.pop()
 
     def walkpat(pat):
         srcs = []
         # TODO: Inline and simplify the non-working-copy version of this code
         # since it shares very little with the working-copy version of it.
         ctx_to_walk = ctx if ctx.rev() is None else pctx
         m = scmutil.match(ctx_to_walk, [pat], opts, globbed=True)
         for abs in ctx_to_walk.walk(m):
             rel = uipathfn(abs)
             exact = m.exact(abs)
             if abs not in ctx:
                 if abs in pctx:
                     if not after:
                         if exact:
                             ui.warn(
                                 _(
                                     b'%s: not copying - file has been marked '
                                     b'for remove\n'
                                 )
                                 % rel
                             )
                         continue
                 else:
                     if exact:
                         ui.warn(
                             _(b'%s: not copying - file is not managed\n') % rel
                         )
                     continue
 
             # abs: hgsep
             # rel: ossep
             srcs.append((abs, rel, exact))
         return srcs
 
     if ctx.rev() is not None:
         rewriteutil.precheck(repo, [ctx.rev()], b'uncopy')
         absdest = pathutil.canonpath(repo.root, cwd, dest)
         if ctx.hasdir(absdest):
             raise error.Abort(
                 _(b'%s: --at-rev does not support a directory as destination')
                 % uipathfn(absdest)
             )
         if absdest not in ctx:
             raise error.Abort(
                 _(b'%s: copy destination does not exist in %s')
                 % (uipathfn(absdest), ctx)
             )
 
         # avoid cycle context -> subrepo -> cmdutil
         from . import context
 
         copylist = []
         for pat in pats:
             srcs = walkpat(pat)
             if not srcs:
                 continue
             for abs, rel, exact in srcs:
                 copylist.append(abs)
 
         if not copylist:
             raise error.Abort(_(b'no files to copy'))
         # TODO: Add support for `hg cp --at-rev . foo bar dir` and
         # `hg cp --at-rev . dir1 dir2`, preferably unifying the code with the
         # existing functions below.
         if len(copylist) != 1:
             raise error.Abort(_(b'--at-rev requires a single source'))
 
         new_ctx = context.overlayworkingctx(repo)
         new_ctx.setbase(ctx.p1())
         mergemod.graft(repo, ctx, wctx=new_ctx)
 
         new_ctx.markcopied(absdest, copylist[0])
 
         with repo.lock():
             mem_ctx = new_ctx.tomemctx_for_amend(ctx)
             new_node = mem_ctx.commit()
 
             if repo.dirstate.p1() == ctx.node():
                 with repo.dirstate.parentchange():
                     scmutil.movedirstate(repo, repo[new_node])
             replacements = {ctx.node(): [new_node]}
             scmutil.cleanupnodes(repo, replacements, b'copy', fixphase=True)
 
         return
 
     # abssrc: hgsep
     # relsrc: ossep
     # otarget: ossep
     def copyfile(abssrc, relsrc, otarget, exact):
         abstarget = pathutil.canonpath(repo.root, cwd, otarget)
         if b'/' in abstarget:
             # We cannot normalize abstarget itself, this would prevent
             # case only renames, like a => A.
             abspath, absname = abstarget.rsplit(b'/', 1)
             abstarget = repo.dirstate.normalize(abspath) + b'/' + absname
         reltarget = repo.pathto(abstarget, cwd)
         target = repo.wjoin(abstarget)
         src = repo.wjoin(abssrc)
         state = repo.dirstate[abstarget]
 
         scmutil.checkportable(ui, abstarget)
 
         # check for collisions
         prevsrc = targets.get(abstarget)
         if prevsrc is not None:
             ui.warn(
                 _(b'%s: not overwriting - %s collides with %s\n')
                 % (
                     reltarget,
                     repo.pathto(abssrc, cwd),
                     repo.pathto(prevsrc, cwd),
                 )
             )
             return True  # report a failure
 
         # check for overwrites
         exists = os.path.lexists(target)
         samefile = False
         if exists and abssrc != abstarget:
             if repo.dirstate.normalize(abssrc) == repo.dirstate.normalize(
                 abstarget
             ):
                 if not rename:
                     ui.warn(_(b"%s: can't copy - same file\n") % reltarget)
                     return True  # report a failure
                 exists = False
                 samefile = True
 
         if not after and exists or after and state in b'mn':
             if not opts[b'force']:
                 if state in b'mn':
                     msg = _(b'%s: not overwriting - file already committed\n')
                     if after:
                         flags = b'--after --force'
                     else:
                         flags = b'--force'
                     if rename:
                         hint = (
                             _(
                                 b"('hg rename %s' to replace the file by "
                                 b'recording a rename)\n'
                             )
                             % flags
                         )
                     else:
                         hint = (
                             _(
                                 b"('hg copy %s' to replace the file by "
                                 b'recording a copy)\n'
                             )
                             % flags
                         )
                 else:
                     msg = _(b'%s: not overwriting - file exists\n')
                     if rename:
                         hint = _(
                             b"('hg rename --after' to record the rename)\n"
                         )
                     else:
                         hint = _(b"('hg copy --after' to record the copy)\n")
                 ui.warn(msg % reltarget)
                 ui.warn(hint)
                 return True  # report a failure
 
         if after:
             if not exists:
                 if rename:
                     ui.warn(
                         _(b'%s: not recording move - %s does not exist\n')
                         % (relsrc, reltarget)
                     )
                 else:
                     ui.warn(
                         _(b'%s: not recording copy - %s does not exist\n')
                         % (relsrc, reltarget)
                     )
                 return True  # report a failure
         elif not dryrun:
             try:
                 if exists:
                     os.unlink(target)
                 targetdir = os.path.dirname(target) or b'.'
                 if not os.path.isdir(targetdir):
                     os.makedirs(targetdir)
                 if samefile:
                     tmp = target + b"~hgrename"
                     os.rename(src, tmp)
                     os.rename(tmp, target)
                 else:
                     # Preserve stat info on renames, not on copies; this matches
                     # Linux CLI behavior.
                     util.copyfile(src, target, copystat=rename)
                 srcexists = True
             except IOError as inst:
                 if inst.errno == errno.ENOENT:
                     ui.warn(_(b'%s: deleted in working directory\n') % relsrc)
                     srcexists = False
                 else:
                     ui.warn(
                         _(b'%s: cannot copy - %s\n')
                         % (relsrc, encoding.strtolocal(inst.strerror))
                     )
                     return True  # report a failure
 
         if ui.verbose or not exact:
             if rename:
                 ui.status(_(b'moving %s to %s\n') % (relsrc, reltarget))
             else:
                 ui.status(_(b'copying %s to %s\n') % (relsrc, reltarget))
 
         targets[abstarget] = abssrc
 
         # fix up dirstate
         scmutil.dirstatecopy(
             ui, repo, ctx, abssrc, abstarget, dryrun=dryrun, cwd=cwd
         )
         if rename and not dryrun:
             if not after and srcexists and not samefile:
                 rmdir = repo.ui.configbool(b'experimental', b'removeemptydirs')
                 repo.wvfs.unlinkpath(abssrc, rmdir=rmdir)
             ctx.forget([abssrc])
 
     # pat: ossep
     # dest ossep
     # srcs: list of (hgsep, hgsep, ossep, bool)
     # return: function that takes hgsep and returns ossep
     def targetpathfn(pat, dest, srcs):
         if os.path.isdir(pat):
             abspfx = pathutil.canonpath(repo.root, cwd, pat)
             abspfx = util.localpath(abspfx)
             if destdirexists:
                 striplen = len(os.path.split(abspfx)[0])
             else:
                 striplen = len(abspfx)
             if striplen:
                 striplen += len(pycompat.ossep)
             res = lambda p: os.path.join(dest, util.localpath(p)[striplen:])
         elif destdirexists:
             res = lambda p: os.path.join(
                 dest, os.path.basename(util.localpath(p))
             )
         else:
             res = lambda p: dest
         return res
 
     # pat: ossep
     # dest ossep
     # srcs: list of (hgsep, hgsep, ossep, bool)
     # return: function that takes hgsep and returns ossep
     def targetpathafterfn(pat, dest, srcs):
         if matchmod.patkind(pat):
             # a mercurial pattern
             res = lambda p: os.path.join(
                 dest, os.path.basename(util.localpath(p))
             )
         else:
             abspfx = pathutil.canonpath(repo.root, cwd, pat)
             if len(abspfx) < len(srcs[0][0]):
                 # A directory. Either the target path contains the last
                 # component of the source path or it does not.
                 def evalpath(striplen):
                     score = 0
                     for s in srcs:
                         t = os.path.join(dest, util.localpath(s[0])[striplen:])
                         if os.path.lexists(t):
                             score += 1
                     return score
 
                 abspfx = util.localpath(abspfx)
                 striplen = len(abspfx)
                 if striplen:
                     striplen += len(pycompat.ossep)
                 if os.path.isdir(os.path.join(dest, os.path.split(abspfx)[1])):
                     score = evalpath(striplen)
                     striplen1 = len(os.path.split(abspfx)[0])
                     if striplen1:
                         striplen1 += len(pycompat.ossep)
                     if evalpath(striplen1) > score:
                         striplen = striplen1
                 res = lambda p: os.path.join(dest, util.localpath(p)[striplen:])
             else:
                 # a file
                 if destdirexists:
                     res = lambda p: os.path.join(
                         dest, os.path.basename(util.localpath(p))
                     )
                 else:
                     res = lambda p: dest
         return res
 
     destdirexists = os.path.isdir(dest) and not os.path.islink(dest)
     if not destdirexists:
         if len(pats) > 1 or matchmod.patkind(pats[0]):
             raise error.Abort(
                 _(
                     b'with multiple sources, destination must be an '
                     b'existing directory'
                 )
             )
         if util.endswithsep(dest):
             raise error.Abort(_(b'destination %s is not a directory') % dest)
 
     tfn = targetpathfn
     if after:
         tfn = targetpathafterfn
     copylist = []
     for pat in pats:
         srcs = walkpat(pat)
         if not srcs:
             continue
         copylist.append((tfn(pat, dest, srcs), srcs))
     if not copylist:
         raise error.Abort(_(b'no files to copy'))
 
     errors = 0
     for targetpath, srcs in copylist:
         for abssrc, relsrc, exact in srcs:
             if copyfile(abssrc, relsrc, targetpath(abssrc), exact):
                 errors += 1
 
     return errors != 0
 
 
 ## facility to let extension process additional data into an import patch
 # list of identifier to be executed in order
 extrapreimport = []  # run before commit
 extrapostimport = []  # run after commit
 # mapping from identifier to actual import function
 #
 # 'preimport' are run before the commit is made and are provided the following
 # arguments:
 # - repo: the localrepository instance,
 # - patchdata: data extracted from patch header (cf m.patch.patchheadermap),
 # - extra: the future extra dictionary of the changeset, please mutate it,
 # - opts: the import options.
 # XXX ideally, we would just pass an ctx ready to be computed, that would allow
 # mutation of in memory commit and more. Feel free to rework the code to get
 # there.
 extrapreimportmap = {}
 # 'postimport' are run after the commit is made and are provided the following
 # argument:
 # - ctx: the changectx created by import.
 extrapostimportmap = {}
 
 
 def tryimportone(ui, repo, patchdata, parents, opts, msgs, updatefunc):
     """Utility function used by commands.import to import a single patch
 
     This function is explicitly defined here to help the evolve extension to
     wrap this part of the import logic.
 
     The API is currently a bit ugly because it a simple code translation from
     the import command. Feel free to make it better.
 
     :patchdata: a dictionary containing parsed patch data (such as from
                 ``patch.extract()``)
     :parents: nodes that will be parent of the created commit
     :opts: the full dict of option passed to the import command
     :msgs: list to save commit message to.
            (used in case we need to save it when failing)
     :updatefunc: a function that update a repo to a given node
                  updatefunc(<repo>, <node>)
     """
     # avoid cycle context -> subrepo -> cmdutil
     from . import context
 
     tmpname = patchdata.get(b'filename')
     message = patchdata.get(b'message')
     user = opts.get(b'user') or patchdata.get(b'user')
     date = opts.get(b'date') or patchdata.get(b'date')
     branch = patchdata.get(b'branch')
     nodeid = patchdata.get(b'nodeid')
     p1 = patchdata.get(b'p1')
     p2 = patchdata.get(b'p2')
 
     nocommit = opts.get(b'no_commit')
     importbranch = opts.get(b'import_branch')
     update = not opts.get(b'bypass')
     strip = opts[b"strip"]
     prefix = opts[b"prefix"]
     sim = float(opts.get(b'similarity') or 0)
 
     if not tmpname:
         return None, None, False
 
     rejects = False
 
     cmdline_message = logmessage(ui, opts)
     if cmdline_message:
         # pickup the cmdline msg
         message = cmdline_message
     elif message:
         # pickup the patch msg
         message = message.strip()
     else:
         # launch the editor
         message = None
     ui.debug(b'message:\n%s\n' % (message or b''))
 
     if len(parents) == 1:
         parents.append(repo[nullid])
     if opts.get(b'exact'):
         if not nodeid or not p1:
             raise error.Abort(_(b'not a Mercurial patch'))
         p1 = repo[p1]
         p2 = repo[p2 or nullid]
     elif p2:
         try:
             p1 = repo[p1]
             p2 = repo[p2]
             # Without any options, consider p2 only if the
             # patch is being applied on top of the recorded
             # first parent.
             if p1 != parents[0]:
                 p1 = parents[0]
                 p2 = repo[nullid]
         except error.RepoError:
             p1, p2 = parents
         if p2.node() == nullid:
             ui.warn(
                 _(
                     b"warning: import the patch as a normal revision\n"
                     b"(use --exact to import the patch as a merge)\n"
                 )
             )
     else:
         p1, p2 = parents
 
     n = None
     if update:
         if p1 != parents[0]:
             updatefunc(repo, p1.node())
         if p2 != parents[1]:
             repo.setparents(p1.node(), p2.node())
 
         if opts.get(b'exact') or importbranch:
             repo.dirstate.setbranch(branch or b'default')
 
         partial = opts.get(b'partial', False)
         files = set()
         try:
             patch.patch(
                 ui,
                 repo,
                 tmpname,
                 strip=strip,
                 prefix=prefix,
                 files=files,
                 eolmode=None,
                 similarity=sim / 100.0,
             )
         except error.PatchError as e:
             if not partial:
                 raise error.Abort(pycompat.bytestr(e))
             if partial:
                 rejects = True
 
         files = list(files)
         if nocommit:
             if message:
                 msgs.append(message)
         else:
             if opts.get(b'exact') or p2:
                 # If you got here, you either use --force and know what
                 # you are doing or used --exact or a merge patch while
                 # being updated to its first parent.
                 m = None
             else:
                 m = scmutil.matchfiles(repo, files or [])
             editform = mergeeditform(repo[None], b'import.normal')
             if opts.get(b'exact'):
                 editor = None
             else:
                 editor = getcommiteditor(
                     editform=editform, **pycompat.strkwargs(opts)
                 )
             extra = {}
             for idfunc in extrapreimport:
                 extrapreimportmap[idfunc](repo, patchdata, extra, opts)
             overrides = {}
             if partial:
                 overrides[(b'ui', b'allowemptycommit')] = True
             if opts.get(b'secret'):
                 overrides[(b'phases', b'new-commit')] = b'secret'
             with repo.ui.configoverride(overrides, b'import'):
                 n = repo.commit(
                     message, user, date, match=m, editor=editor, extra=extra
                 )
                 for idfunc in extrapostimport:
                     extrapostimportmap[idfunc](repo[n])
     else:
         if opts.get(b'exact') or importbranch:
             branch = branch or b'default'
         else:
             branch = p1.branch()
         store = patch.filestore()
         try:
             files = set()
             try:
                 patch.patchrepo(
                     ui,
                     repo,
                     p1,
                     store,
                     tmpname,
                     strip,
                     prefix,
                     files,
                     eolmode=None,
                 )
             except error.PatchError as e:
                 raise error.Abort(stringutil.forcebytestr(e))
             if opts.get(b'exact'):
                 editor = None
             else:
                 editor = getcommiteditor(editform=b'import.bypass')
             memctx = context.memctx(
                 repo,
                 (p1.node(), p2.node()),
                 message,
                 files=files,
                 filectxfn=store,
                 user=user,
                 date=date,
                 branch=branch,
                 editor=editor,
             )
 
             overrides = {}
             if opts.get(b'secret'):
                 overrides[(b'phases', b'new-commit')] = b'secret'
             with repo.ui.configoverride(overrides, b'import'):
                 n = memctx.commit()
         finally:
             store.close()
     if opts.get(b'exact') and nocommit:
         # --exact with --no-commit is still useful in that it does merge
         # and branch bits
         ui.warn(_(b"warning: can't check exact import with --no-commit\n"))
     elif opts.get(b'exact') and (not n or hex(n) != nodeid):
         raise error.Abort(_(b'patch is damaged or loses information'))
     msg = _(b'applied to working directory')
     if n:
         # i18n: refers to a short changeset id
         msg = _(b'created %s') % short(n)
     return msg, n, rejects
 
 
 # facility to let extensions include additional data in an exported patch
 # list of identifiers to be executed in order
 extraexport = []
 # mapping from identifier to actual export function
 # function as to return a string to be added to the header or None
 # it is given two arguments (sequencenumber, changectx)
 extraexportmap = {}
 
 
 def _exportsingle(repo, ctx, fm, match, switch_parent, seqno, diffopts):
     node = scmutil.binnode(ctx)
     parents = [p.node() for p in ctx.parents() if p]
     branch = ctx.branch()
     if switch_parent:
         parents.reverse()
 
     if parents:
         prev = parents[0]
     else:
         prev = nullid
 
     fm.context(ctx=ctx)
     fm.plain(b'# HG changeset patch\n')
     fm.write(b'user', b'# User %s\n', ctx.user())
     fm.plain(b'# Date %d %d\n' % ctx.date())
     fm.write(b'date', b'#      %s\n', fm.formatdate(ctx.date()))
     fm.condwrite(
         branch and branch != b'default', b'branch', b'# Branch %s\n', branch
     )
     fm.write(b'node', b'# Node ID %s\n', hex(node))
     fm.plain(b'# Parent  %s\n' % hex(prev))
     if len(parents) > 1:
         fm.plain(b'# Parent  %s\n' % hex(parents[1]))
     fm.data(parents=fm.formatlist(pycompat.maplist(hex, parents), name=b'node'))
 
     # TODO: redesign extraexportmap function to support formatter
     for headerid in extraexport:
         header = extraexportmap[headerid](seqno, ctx)
         if header is not None:
             fm.plain(b'# %s\n' % header)
 
     fm.write(b'desc', b'%s\n', ctx.description().rstrip())
     fm.plain(b'\n')
 
     if fm.isplain():
         chunkiter = patch.diffui(repo, prev, node, match, opts=diffopts)
         for chunk, label in chunkiter:
             fm.plain(chunk, label=label)
     else:
         chunkiter = patch.diff(repo, prev, node, match, opts=diffopts)
         # TODO: make it structured?
         fm.data(diff=b''.join(chunkiter))
 
 
 def _exportfile(repo, revs, fm, dest, switch_parent, diffopts, match):
     """Export changesets to stdout or a single file"""
     for seqno, rev in enumerate(revs, 1):
         ctx = repo[rev]
         if not dest.startswith(b'<'):
             repo.ui.note(b"%s\n" % dest)
         fm.startitem()
         _exportsingle(repo, ctx, fm, match, switch_parent, seqno, diffopts)
 
 
 def _exportfntemplate(
     repo, revs, basefm, fntemplate, switch_parent, diffopts, match
 ):
     """Export changesets to possibly multiple files"""
     total = len(revs)
     revwidth = max(len(str(rev)) for rev in revs)
     filemap = util.sortdict()  # filename: [(seqno, rev), ...]
 
     for seqno, rev in enumerate(revs, 1):
         ctx = repo[rev]
         dest = makefilename(
             ctx, fntemplate, total=total, seqno=seqno, revwidth=revwidth
         )
         filemap.setdefault(dest, []).append((seqno, rev))
 
     for dest in filemap:
         with formatter.maybereopen(basefm, dest) as fm:
             repo.ui.note(b"%s\n" % dest)
             for seqno, rev in filemap[dest]:
                 fm.startitem()
                 ctx = repo[rev]
                 _exportsingle(
                     repo, ctx, fm, match, switch_parent, seqno, diffopts
                 )
 
 
 def _prefetchchangedfiles(repo, revs, match):
     allfiles = set()
     for rev in revs:
         for file in repo[rev].files():
             if not match or match(file):
                 allfiles.add(file)
     match = scmutil.matchfiles(repo, allfiles)
     revmatches = [(rev, match) for rev in revs]
     scmutil.prefetchfiles(repo, revmatches)
 
 
 def export(
     repo,
     revs,
     basefm,
     fntemplate=b'hg-%h.patch',
     switch_parent=False,
     opts=None,
     match=None,
 ):
     '''export changesets as hg patches
 
     Args:
       repo: The repository from which we're exporting revisions.
       revs: A list of revisions to export as revision numbers.
       basefm: A formatter to which patches should be written.
       fntemplate: An optional string to use for generating patch file names.
       switch_parent: If True, show diffs against second parent when not nullid.
                      Default is false, which always shows diff against p1.
       opts: diff options to use for generating the patch.
       match: If specified, only export changes to files matching this matcher.
 
     Returns:
       Nothing.
 
     Side Effect:
       "HG Changeset Patch" data is emitted to one of the following
       destinations:
         fntemplate specified: Each rev is written to a unique file named using
                             the given template.
         Otherwise: All revs will be written to basefm.
     '''
     _prefetchchangedfiles(repo, revs, match)
 
     if not fntemplate:
         _exportfile(
             repo, revs, basefm, b'<unnamed>', switch_parent, opts, match
         )
     else:
         _exportfntemplate(
             repo, revs, basefm, fntemplate, switch_parent, opts, match
         )
 
 
 def exportfile(repo, revs, fp, switch_parent=False, opts=None, match=None):
     """Export changesets to the given file stream"""
     _prefetchchangedfiles(repo, revs, match)
 
     dest = getattr(fp, 'name', b'<unnamed>')
     with formatter.formatter(repo.ui, fp, b'export', {}) as fm:
         _exportfile(repo, revs, fm, dest, switch_parent, opts, match)
 
 
 def showmarker(fm, marker, index=None):
     """utility function to display obsolescence marker in a readable way
 
     To be used by debug function."""
     if index is not None:
         fm.write(b'index', b'%i ', index)
     fm.write(b'prednode', b'%s ', hex(marker.prednode()))
     succs = marker.succnodes()
     fm.condwrite(
         succs,
         b'succnodes',
         b'%s ',
         fm.formatlist(map(hex, succs), name=b'node'),
     )
     fm.write(b'flag', b'%X ', marker.flags())
     parents = marker.parentnodes()
     if parents is not None:
         fm.write(
             b'parentnodes',
             b'{%s} ',
             fm.formatlist(map(hex, parents), name=b'node', sep=b', '),
         )
     fm.write(b'date', b'(%s) ', fm.formatdate(marker.date()))
     meta = marker.metadata().copy()
     meta.pop(b'date', None)
     smeta = pycompat.rapply(pycompat.maybebytestr, meta)
     fm.write(
         b'metadata', b'{%s}', fm.formatdict(smeta, fmt=b'%r: %r', sep=b', ')
     )
     fm.plain(b'\n')
 
 
 def finddate(ui, repo, date):
     """Find the tipmost changeset that matches the given date spec"""
     mrevs = repo.revs(b'date(%s)', date)
     try:
         rev = mrevs.max()
     except ValueError:
         raise error.Abort(_(b"revision matching date not found"))
 
     ui.status(
         _(b"found revision %d from %s\n")
         % (rev, dateutil.datestr(repo[rev].date()))
     )
     return b'%d' % rev
 
 
 def increasingwindows(windowsize=8, sizelimit=512):
     while True:
         yield windowsize
         if windowsize < sizelimit:
             windowsize *= 2
 
 
-def _walkrevs(repo, opts):
-    # Default --rev value depends on --follow but --follow behavior
-    # depends on revisions resolved from --rev...
-    follow = opts.get(b'follow') or opts.get(b'follow_first')
-    revspec = opts.get(b'rev')
-    if follow and revspec:
-        revs = scmutil.revrange(repo, revspec)
-        revs = repo.revs(b'reverse(::%ld)', revs)
-    elif revspec:
-        revs = scmutil.revrange(repo, revspec)
-    elif follow and repo.dirstate.p1() == nullid:
-        revs = smartset.baseset()
-    elif follow:
-        revs = repo.revs(b'reverse(:.)')
-    else:
-        revs = smartset.spanset(repo)
-        revs.reverse()
-    return revs
-
-
-class FileWalkError(Exception):
-    pass
-
-
-def walkfilerevs(repo, match, follow, revs, fncache):
-    '''Walks the file history for the matched files.
-
-    Returns the changeset revs that are involved in the file history.
-
-    Throws FileWalkError if the file history can't be walked using
-    filelogs alone.
-    '''
-    wanted = set()
-    copies = []
-    minrev, maxrev = min(revs), max(revs)
-
-    def filerevs(filelog, last):
-        """
-        Only files, no patterns.  Check the history of each file.
-
-        Examines filelog entries within minrev, maxrev linkrev range
-        Returns an iterator yielding (linkrev, parentlinkrevs, copied)
-        tuples in backwards order
-        """
-        cl_count = len(repo)
-        revs = []
-        for j in pycompat.xrange(0, last + 1):
-            linkrev = filelog.linkrev(j)
-            if linkrev < minrev:
-                continue
-            # only yield rev for which we have the changelog, it can
-            # happen while doing "hg log" during a pull or commit
-            if linkrev >= cl_count:
-                break
-
-            parentlinkrevs = []
-            for p in filelog.parentrevs(j):
-                if p != nullrev:
-                    parentlinkrevs.append(filelog.linkrev(p))
-            n = filelog.node(j)
-            revs.append(
-                (linkrev, parentlinkrevs, follow and filelog.renamed(n))
-            )
-
-        return reversed(revs)
-
-    def iterfiles():
-        pctx = repo[b'.']
-        for filename in match.files():
-            if follow:
-                if filename not in pctx:
-                    raise error.Abort(
-                        _(
-                            b'cannot follow file not in parent '
-                            b'revision: "%s"'
-                        )
-                        % filename
-                    )
-                yield filename, pctx[filename].filenode()
-            else:
-                yield filename, None
-        for filename_node in copies:
-            yield filename_node
-
-    for file_, node in iterfiles():
-        filelog = repo.file(file_)
-        if not len(filelog):
-            if node is None:
-                # A zero count may be a directory or deleted file, so
-                # try to find matching entries on the slow path.
-                if follow:
-                    raise error.Abort(
-                        _(b'cannot follow nonexistent file: "%s"') % file_
-                    )
-                raise FileWalkError(b"Cannot walk via filelog")
-            else:
-                continue
-
-        if node is None:
-            last = len(filelog) - 1
-        else:
-            last = filelog.rev(node)
-
-        # keep track of all ancestors of the file
-        ancestors = {filelog.linkrev(last)}
-
-        # iterate from latest to oldest revision
-        for rev, flparentlinkrevs, copied in filerevs(filelog, last):
-            if not follow:
-                if rev > maxrev:
-                    continue
-            else:
-                # Note that last might not be the first interesting
-                # rev to us:
-                # if the file has been changed after maxrev, we'll
-                # have linkrev(last) > maxrev, and we still need
-                # to explore the file graph
-                if rev not in ancestors:
-                    continue
-                # XXX insert 1327 fix here
-                if flparentlinkrevs:
-                    ancestors.update(flparentlinkrevs)
-
-            fncache.setdefault(rev, []).append(file_)
-            wanted.add(rev)
-            if copied:
-                copies.append(copied)
-
-    return wanted
-
-
-class _followfilter(object):
-    def __init__(self, repo, onlyfirst=False):
-        self.repo = repo
-        self.startrev = nullrev
-        self.roots = set()
-        self.onlyfirst = onlyfirst
-
-    def match(self, rev):
-        def realparents(rev):
-            try:
-                if self.onlyfirst:
-                    return self.repo.changelog.parentrevs(rev)[0:1]
-                else:
-                    return filter(
-                        lambda x: x != nullrev,
-                        self.repo.changelog.parentrevs(rev),
-                    )
-            except error.WdirUnsupported:
-                prevs = [p.rev() for p in self.repo[rev].parents()]
-                if self.onlyfirst:
-                    return prevs[:1]
-                else:
-                    return prevs
-
-        if self.startrev == nullrev:
-            self.startrev = rev
-            return True
-
-        if rev > self.startrev:
-            # forward: all descendants
-            if not self.roots:
-                self.roots.add(self.startrev)
-            for parent in realparents(rev):
-                if parent in self.roots:
-                    self.roots.add(rev)
-                    return True
-        else:
-            # backwards: all parents
-            if not self.roots:
-                self.roots.update(realparents(self.startrev))
-            if rev in self.roots:
-                self.roots.remove(rev)
-                self.roots.update(realparents(rev))
-                return True
-
-        return False
-
-
 def walkchangerevs(repo, revs, makefilematcher, prepare):
     '''Iterate over files and the revs in a "windowed" way.
 
     Callers most commonly need to iterate backwards over the history
     in which they are interested. Doing so has awful (quadratic-looking)
     performance, so we use iterators in a "windowed" way.
 
     We walk a window of revisions in the desired order.  Within the
     window, we first walk forwards to gather data, then in the desired
     order (usually backwards) to display it.
 
     This function returns an iterator yielding contexts. Before
     yielding each context, the iterator will first call the prepare
     function on each context in the window in forward order.'''
 
     if not revs:
         return []
     change = repo.__getitem__
 
     def iterate():
         it = iter(revs)
         stopiteration = False
         for windowsize in increasingwindows():
             nrevs = []
             for i in pycompat.xrange(windowsize):
                 rev = next(it, None)
                 if rev is None:
                     stopiteration = True
                     break
                 nrevs.append(rev)
             for rev in sorted(nrevs):
                 ctx = change(rev)
                 prepare(ctx, makefilematcher(ctx))
             for rev in nrevs:
                 yield change(rev)
 
             if stopiteration:
                 break
 
     return iterate()
 
 
 def add(ui, repo, match, prefix, uipathfn, explicitonly, **opts):
     bad = []
 
     badfn = lambda x, y: bad.append(x) or match.bad(x, y)
     names = []
     wctx = repo[None]
     cca = None
     abort, warn = scmutil.checkportabilityalert(ui)
     if abort or warn:
         cca = scmutil.casecollisionauditor(ui, abort, repo.dirstate)
 
     match = repo.narrowmatch(match, includeexact=True)
     badmatch = matchmod.badmatch(match, badfn)
     dirstate = repo.dirstate
     # We don't want to just call wctx.walk here, since it would return a lot of
     # clean files, which we aren't interested in and takes time.
     for f in sorted(
         dirstate.walk(
             badmatch,
             subrepos=sorted(wctx.substate),
             unknown=True,
             ignored=False,
             full=False,
         )
     ):
         exact = match.exact(f)
         if exact or not explicitonly and f not in wctx and repo.wvfs.lexists(f):
             if cca:
                 cca(f)
             names.append(f)
             if ui.verbose or not exact:
                 ui.status(
                     _(b'adding %s\n') % uipathfn(f), label=b'ui.addremove.added'
                 )
 
     for subpath in sorted(wctx.substate):
         sub = wctx.sub(subpath)
         try:
             submatch = matchmod.subdirmatcher(subpath, match)
             subprefix = repo.wvfs.reljoin(prefix, subpath)
             subuipathfn = scmutil.subdiruipathfn(subpath, uipathfn)
             if opts.get('subrepos'):
                 bad.extend(
                     sub.add(ui, submatch, subprefix, subuipathfn, False, **opts)
                 )
             else:
                 bad.extend(
                     sub.add(ui, submatch, subprefix, subuipathfn, True, **opts)
                 )
         except error.LookupError:
             ui.status(
                 _(b"skipping missing subrepository: %s\n") % uipathfn(subpath)
             )
 
     if not opts.get('dry_run'):
         rejected = wctx.add(names, prefix)
         bad.extend(f for f in rejected if f in match.files())
     return bad
 
 
 def addwebdirpath(repo, serverpath, webconf):
     webconf[serverpath] = repo.root
     repo.ui.debug(b'adding %s = %s\n' % (serverpath, repo.root))
 
     for r in repo.revs(b'filelog("path:.hgsub")'):
         ctx = repo[r]
         for subpath in ctx.substate:
             ctx.sub(subpath).addwebdirpath(serverpath, webconf)
 
 
 def forget(
     ui, repo, match, prefix, uipathfn, explicitonly, dryrun, interactive
 ):
     if dryrun and interactive:
         raise error.Abort(_(b"cannot specify both --dry-run and --interactive"))
     bad = []
     badfn = lambda x, y: bad.append(x) or match.bad(x, y)
     wctx = repo[None]
     forgot = []
 
     s = repo.status(match=matchmod.badmatch(match, badfn), clean=True)
     forget = sorted(s.modified + s.added + s.deleted + s.clean)
     if explicitonly:
         forget = [f for f in forget if match.exact(f)]
 
     for subpath in sorted(wctx.substate):
         sub = wctx.sub(subpath)
         submatch = matchmod.subdirmatcher(subpath, match)
         subprefix = repo.wvfs.reljoin(prefix, subpath)
         subuipathfn = scmutil.subdiruipathfn(subpath, uipathfn)
         try:
             subbad, subforgot = sub.forget(
                 submatch,
                 subprefix,
                 subuipathfn,
                 dryrun=dryrun,
                 interactive=interactive,
             )
             bad.extend([subpath + b'/' + f for f in subbad])
             forgot.extend([subpath + b'/' + f for f in subforgot])
         except error.LookupError:
             ui.status(
                 _(b"skipping missing subrepository: %s\n") % uipathfn(subpath)
             )
 
     if not explicitonly:
         for f in match.files():
             if f not in repo.dirstate and not repo.wvfs.isdir(f):
                 if f not in forgot:
                     if repo.wvfs.exists(f):
                         # Don't complain if the exact case match wasn't given.
                         # But don't do this until after checking 'forgot', so
                         # that subrepo files aren't normalized, and this op is
                         # purely from data cached by the status walk above.
                         if repo.dirstate.normalize(f) in repo.dirstate:
                             continue
                         ui.warn(
                             _(
                                 b'not removing %s: '
                                 b'file is already untracked\n'
                             )
                             % uipathfn(f)
                         )
                     bad.append(f)
 
     if interactive:
         responses = _(
             b'[Ynsa?]'
             b'$$ &Yes, forget this file'
             b'$$ &No, skip this file'
             b'$$ &Skip remaining files'
             b'$$ Include &all remaining files'
             b'$$ &? (display help)'
         )
         for filename in forget[:]:
             r = ui.promptchoice(
                 _(b'forget %s %s') % (uipathfn(filename), responses)
             )
             if r == 4:  # ?
                 while r == 4:
                     for c, t in ui.extractchoices(responses)[1]:
                         ui.write(b'%s - %s\n' % (c, encoding.lower(t)))
                     r = ui.promptchoice(
                         _(b'forget %s %s') % (uipathfn(filename), responses)
                     )
             if r == 0:  # yes
                 continue
             elif r == 1:  # no
                 forget.remove(filename)
             elif r == 2:  # Skip
                 fnindex = forget.index(filename)
                 del forget[fnindex:]
                 break
             elif r == 3:  # All
                 break
 
     for f in forget:
         if ui.verbose or not match.exact(f) or interactive:
             ui.status(
                 _(b'removing %s\n') % uipathfn(f), label=b'ui.addremove.removed'
             )
 
     if not dryrun:
         rejected = wctx.forget(forget, prefix)
         bad.extend(f for f in rejected if f in match.files())
         forgot.extend(f for f in forget if f not in rejected)
     return bad, forgot
 
 
 def files(ui, ctx, m, uipathfn, fm, fmt, subrepos):
     ret = 1
 
     needsfctx = ui.verbose or {b'size', b'flags'} & fm.datahint()
     if fm.isplain() and not needsfctx:
         # Fast path. The speed-up comes from skipping the formatter, and batching
         # calls to ui.write.
         buf = []
         for f in ctx.matches(m):
             buf.append(fmt % uipathfn(f))
             if len(buf) > 100:
                 ui.write(b''.join(buf))
                 del buf[:]
             ret = 0
         if buf:
             ui.write(b''.join(buf))
     else:
         for f in ctx.matches(m):
             fm.startitem()
             fm.context(ctx=ctx)
             if needsfctx:
                 fc = ctx[f]
                 fm.write(b'size flags', b'% 10d % 1s ', fc.size(), fc.flags())
             fm.data(path=f)
             fm.plain(fmt % uipathfn(f))
             ret = 0
 
     for subpath in sorted(ctx.substate):
         submatch = matchmod.subdirmatcher(subpath, m)
         subuipathfn = scmutil.subdiruipathfn(subpath, uipathfn)
         if subrepos or m.exact(subpath) or any(submatch.files()):
             sub = ctx.sub(subpath)
             try:
                 recurse = m.exact(subpath) or subrepos
                 if (
                     sub.printfiles(ui, submatch, subuipathfn, fm, fmt, recurse)
                     == 0
                 ):
                     ret = 0
             except error.LookupError:
                 ui.status(
                     _(b"skipping missing subrepository: %s\n")
                     % uipathfn(subpath)
                 )
 
     return ret
 
 
 def remove(
     ui, repo, m, prefix, uipathfn, after, force, subrepos, dryrun, warnings=None
 ):
     ret = 0
     s = repo.status(match=m, clean=True)
     modified, added, deleted, clean = s.modified, s.added, s.deleted, s.clean
 
     wctx = repo[None]
 
     if warnings is None:
         warnings = []
         warn = True
     else:
         warn = False
 
     subs = sorted(wctx.substate)
     progress = ui.makeprogress(
         _(b'searching'), total=len(subs), unit=_(b'subrepos')
     )
     for subpath in subs:
         submatch = matchmod.subdirmatcher(subpath, m)
         subprefix = repo.wvfs.reljoin(prefix, subpath)
         subuipathfn = scmutil.subdiruipathfn(subpath, uipathfn)
         if subrepos or m.exact(subpath) or any(submatch.files()):
             progress.increment()
             sub = wctx.sub(subpath)
             try:
                 if sub.removefiles(
                     submatch,
                     subprefix,
                     subuipathfn,
                     after,
                     force,
                     subrepos,
                     dryrun,
                     warnings,
                 ):
                     ret = 1
             except error.LookupError:
                 warnings.append(
                     _(b"skipping missing subrepository: %s\n")
                     % uipathfn(subpath)
                 )
     progress.complete()
 
     # warn about failure to delete explicit files/dirs
     deleteddirs = pathutil.dirs(deleted)
     files = m.files()
     progress = ui.makeprogress(
         _(b'deleting'), total=len(files), unit=_(b'files')
     )
     for f in files:
 
         def insubrepo():
             for subpath in wctx.substate:
                 if f.startswith(subpath + b'/'):
                     return True
             return False
 
         progress.increment()
         isdir = f in deleteddirs or wctx.hasdir(f)
         if f in repo.dirstate or isdir or f == b'.' or insubrepo() or f in subs:
             continue
 
         if repo.wvfs.exists(f):
             if repo.wvfs.isdir(f):
                 warnings.append(
                     _(b'not removing %s: no tracked files\n') % uipathfn(f)
                 )
             else:
                 warnings.append(
                     _(b'not removing %s: file is untracked\n') % uipathfn(f)
                 )
         # missing files will generate a warning elsewhere
         ret = 1
     progress.complete()
 
     if force:
         list = modified + deleted + clean + added
     elif after:
         list = deleted
         remaining = modified + added + clean
         progress = ui.makeprogress(
             _(b'skipping'), total=len(remaining), unit=_(b'files')
         )
         for f in remaining:
             progress.increment()
             if ui.verbose or (f in files):
                 warnings.append(
                     _(b'not removing %s: file still exists\n') % uipathfn(f)
                 )
             ret = 1
         progress.complete()
     else:
         list = deleted + clean
         progress = ui.makeprogress(
             _(b'skipping'), total=(len(modified) + len(added)), unit=_(b'files')
         )
         for f in modified:
             progress.increment()
             warnings.append(
                 _(
                     b'not removing %s: file is modified (use -f'
                     b' to force removal)\n'
                 )
                 % uipathfn(f)
             )
             ret = 1
         for f in added:
             progress.increment()
             warnings.append(
                 _(
                     b"not removing %s: file has been marked for add"
                     b" (use 'hg forget' to undo add)\n"
                 )
                 % uipathfn(f)
             )
             ret = 1
         progress.complete()
 
     list = sorted(list)
     progress = ui.makeprogress(
         _(b'deleting'), total=len(list), unit=_(b'files')
     )
     for f in list:
         if ui.verbose or not m.exact(f):
             progress.increment()
             ui.status(
                 _(b'removing %s\n') % uipathfn(f), label=b'ui.addremove.removed'
             )
     progress.complete()
 
     if not dryrun:
         with repo.wlock():
             if not after:
                 for f in list:
                     if f in added:
                         continue  # we never unlink added files on remove
                     rmdir = repo.ui.configbool(
                         b'experimental', b'removeemptydirs'
                     )
                     repo.wvfs.unlinkpath(f, ignoremissing=True, rmdir=rmdir)
             repo[None].forget(list)
 
     if warn:
         for warning in warnings:
             ui.warn(warning)
 
     return ret
 
 
 def _catfmtneedsdata(fm):
     return not fm.datahint() or b'data' in fm.datahint()
 
 
 def _updatecatformatter(fm, ctx, matcher, path, decode):
     """Hook for adding data to the formatter used by ``hg cat``.
 
     Extensions (e.g., lfs) can wrap this to inject keywords/data, but must call
     this method first."""
 
     # data() can be expensive to fetch (e.g. lfs), so don't fetch it if it
     # wasn't requested.
     data = b''
     if _catfmtneedsdata(fm):
         data = ctx[path].data()
         if decode:
             data = ctx.repo().wwritedata(path, data)
     fm.startitem()
     fm.context(ctx=ctx)
     fm.write(b'data', b'%s', data)
     fm.data(path=path)
 
 
 def cat(ui, repo, ctx, matcher, basefm, fntemplate, prefix, **opts):
     err = 1
     opts = pycompat.byteskwargs(opts)
 
     def write(path):
         filename = None
         if fntemplate:
             filename = makefilename(
                 ctx, fntemplate, pathname=os.path.join(prefix, path)
             )
             # attempt to create the directory if it does not already exist
             try:
                 os.makedirs(os.path.dirname(filename))
             except OSError:
                 pass
         with formatter.maybereopen(basefm, filename) as fm:
             _updatecatformatter(fm, ctx, matcher, path, opts.get(b'decode'))
 
     # Automation often uses hg cat on single files, so special case it
     # for performance to avoid the cost of parsing the manifest.
     if len(matcher.files()) == 1 and not matcher.anypats():
         file = matcher.files()[0]
         mfl = repo.manifestlog
         mfnode = ctx.manifestnode()
         try:
             if mfnode and mfl[mfnode].find(file)[0]:
                 if _catfmtneedsdata(basefm):
                     scmutil.prefetchfiles(repo, [(ctx.rev(), matcher)])
                 write(file)
                 return 0
         except KeyError:
             pass
 
     if _catfmtneedsdata(basefm):
         scmutil.prefetchfiles(repo, [(ctx.rev(), matcher)])
 
     for abs in ctx.walk(matcher):
         write(abs)
         err = 0
 
     uipathfn = scmutil.getuipathfn(repo, legacyrelativevalue=True)
     for subpath in sorted(ctx.substate):
         sub = ctx.sub(subpath)
         try:
             submatch = matchmod.subdirmatcher(subpath, matcher)
             subprefix = os.path.join(prefix, subpath)
             if not sub.cat(
                 submatch,
                 basefm,
                 fntemplate,
                 subprefix,
                 **pycompat.strkwargs(opts)
             ):
                 err = 0
         except error.RepoLookupError:
             ui.status(
                 _(b"skipping missing subrepository: %s\n") % uipathfn(subpath)
             )
 
     return err
 
 
 def commit(ui, repo, commitfunc, pats, opts):
     '''commit the specified files or all outstanding changes'''
     date = opts.get(b'date')
     if date:
         opts[b'date'] = dateutil.parsedate(date)
     message = logmessage(ui, opts)
     matcher = scmutil.match(repo[None], pats, opts)
 
     dsguard = None
     # extract addremove carefully -- this function can be called from a command
     # that doesn't support addremove
     if opts.get(b'addremove'):
         dsguard = dirstateguard.dirstateguard(repo, b'commit')
     with dsguard or util.nullcontextmanager():
         if dsguard:
             relative = scmutil.anypats(pats, opts)
             uipathfn = scmutil.getuipathfn(repo, legacyrelativevalue=relative)
             if scmutil.addremove(repo, matcher, b"", uipathfn, opts) != 0:
                 raise error.Abort(
                     _(b"failed to mark all new/missing files as added/removed")
                 )
 
         return commitfunc(ui, repo, message, matcher, opts)
 
 
 def samefile(f, ctx1, ctx2):
     if f in ctx1.manifest():
         a = ctx1.filectx(f)
         if f in ctx2.manifest():
             b = ctx2.filectx(f)
             return not a.cmp(b) and a.flags() == b.flags()
         else:
             return False
     else:
         return f not in ctx2.manifest()
 
 
 def amend(ui, repo, old, extra, pats, opts):
     # avoid cycle context -> subrepo -> cmdutil
     from . import context
 
     # amend will reuse the existing user if not specified, but the obsolete
     # marker creation requires that the current user's name is specified.
     if obsolete.isenabled(repo, obsolete.createmarkersopt):
         ui.username()  # raise exception if username not set
 
     ui.note(_(b'amending changeset %s\n') % old)
     base = old.p1()
 
     with repo.wlock(), repo.lock(), repo.transaction(b'amend'):
         # Participating changesets:
         #
         # wctx     o - workingctx that contains changes from working copy
         #          |   to go into amending commit
         #          |
         # old      o - changeset to amend
         #          |
         # base     o - first parent of the changeset to amend
         wctx = repo[None]
 
         # Copy to avoid mutating input
         extra = extra.copy()
         # Update extra dict from amended commit (e.g. to preserve graft
         # source)
         extra.update(old.extra())
 
         # Also update it from the from the wctx
         extra.update(wctx.extra())
 
         # date-only change should be ignored?
         datemaydiffer = resolvecommitoptions(ui, opts)
 
         date = old.date()
         if opts.get(b'date'):
             date = dateutil.parsedate(opts.get(b'date'))
         user = opts.get(b'user') or old.user()
 
         if len(old.parents()) > 1:
             # ctx.files() isn't reliable for merges, so fall back to the
             # slower repo.status() method
             st = base.status(old)
             files = set(st.modified) | set(st.added) | set(st.removed)
         else:
             files = set(old.files())
 
         # add/remove the files to the working copy if the "addremove" option
         # was specified.
         matcher = scmutil.match(wctx, pats, opts)
         relative = scmutil.anypats(pats, opts)
         uipathfn = scmutil.getuipathfn(repo, legacyrelativevalue=relative)
         if opts.get(b'addremove') and scmutil.addremove(
             repo, matcher, b"", uipathfn, opts
         ):
             raise error.Abort(
                 _(b"failed to mark all new/missing files as added/removed")
             )
 
         # Check subrepos. This depends on in-place wctx._status update in
         # subrepo.precommit(). To minimize the risk of this hack, we do
         # nothing if .hgsub does not exist.
         if b'.hgsub' in wctx or b'.hgsub' in old:
             subs, commitsubs, newsubstate = subrepoutil.precommit(
                 ui, wctx, wctx._status, matcher
             )
             # amend should abort if commitsubrepos is enabled
             assert not commitsubs
             if subs:
                 subrepoutil.writestate(repo, newsubstate)
 
         ms = mergestatemod.mergestate.read(repo)
         mergeutil.checkunresolved(ms)
 
         filestoamend = {f for f in wctx.files() if matcher(f)}
 
         changes = len(filestoamend) > 0
         if changes:
             # Recompute copies (avoid recording a -> b -> a)
             copied = copies.pathcopies(base, wctx, matcher)
             if old.p2:
                 copied.update(copies.pathcopies(old.p2(), wctx, matcher))
 
             # Prune files which were reverted by the updates: if old
             # introduced file X and the file was renamed in the working
             # copy, then those two files are the same and
             # we can discard X from our list of files. Likewise if X
             # was removed, it's no longer relevant. If X is missing (aka
             # deleted), old X must be preserved.
             files.update(filestoamend)
             files = [
                 f
                 for f in files
                 if (f not in filestoamend or not samefile(f, wctx, base))
             ]
 
             def filectxfn(repo, ctx_, path):
                 try:
                     # If the file being considered is not amongst the files
                     # to be amended, we should return the file context from the
                     # old changeset. This avoids issues when only some files in
                     # the working copy are being amended but there are also
                     # changes to other files from the old changeset.
                     if path not in filestoamend:
                         return old.filectx(path)
 
                     # Return None for removed files.
                     if path in wctx.removed():
                         return None
 
                     fctx = wctx[path]
                     flags = fctx.flags()
                     mctx = context.memfilectx(
                         repo,
                         ctx_,
                         fctx.path(),
                         fctx.data(),
                         islink=b'l' in flags,
                         isexec=b'x' in flags,
                         copysource=copied.get(path),
                     )
                     return mctx
                 except KeyError:
                     return None
 
         else:
             ui.note(_(b'copying changeset %s to %s\n') % (old, base))
 
             # Use version of files as in the old cset
             def filectxfn(repo, ctx_, path):
                 try:
                     return old.filectx(path)
                 except KeyError:
                     return None
 
         # See if we got a message from -m or -l, if not, open the editor with
         # the message of the changeset to amend.
         message = logmessage(ui, opts)
 
         editform = mergeeditform(old, b'commit.amend')
 
         if not message:
             message = old.description()
             # Default if message isn't provided and --edit is not passed is to
             # invoke editor, but allow --no-edit. If somehow we don't have any
             # description, let's always start the editor.
             doedit = not message or opts.get(b'edit') in [True, None]
         else:
             # Default if message is provided is to not invoke editor, but allow
             # --edit.
             doedit = opts.get(b'edit') is True
         editor = getcommiteditor(edit=doedit, editform=editform)
 
         pureextra = extra.copy()
         extra[b'amend_source'] = old.hex()
 
         new = context.memctx(
             repo,
             parents=[base.node(), old.p2().node()],
             text=message,
             files=files,
             filectxfn=filectxfn,
             user=user,
             date=date,
             extra=extra,
             editor=editor,
         )
 
         newdesc = changelog.stripdesc(new.description())
         if (
             (not changes)
             and newdesc == old.description()
             and user == old.user()
             and (date == old.date() or datemaydiffer)
             and pureextra == old.extra()
         ):
             # nothing changed. continuing here would create a new node
             # anyway because of the amend_source noise.
             #
             # This not what we expect from amend.
             return old.node()
 
         commitphase = None
         if opts.get(b'secret'):
             commitphase = phases.secret
         newid = repo.commitctx(new)
         ms.reset()
 
         # Reroute the working copy parent to the new changeset
         repo.setparents(newid, nullid)
         mapping = {old.node(): (newid,)}
         obsmetadata = None
         if opts.get(b'note'):
             obsmetadata = {b'note': encoding.fromlocal(opts[b'note'])}
         backup = ui.configbool(b'rewrite', b'backup-bundle')
         scmutil.cleanupnodes(
             repo,
             mapping,
             b'amend',
             metadata=obsmetadata,
             fixphase=True,
             targetphase=commitphase,
             backup=backup,
         )
 
         # Fixing the dirstate because localrepo.commitctx does not update
         # it. This is rather convenient because we did not need to update
         # the dirstate for all the files in the new commit which commitctx
         # could have done if it updated the dirstate. Now, we can
         # selectively update the dirstate only for the amended files.
         dirstate = repo.dirstate
 
         # Update the state of the files which were added and modified in the
         # amend to "normal" in the dirstate. We need to use "normallookup" since
         # the files may have changed since the command started; using "normal"
         # would mark them as clean but with uncommitted contents.
         normalfiles = set(wctx.modified() + wctx.added()) & filestoamend
         for f in normalfiles:
             dirstate.normallookup(f)
 
         # Update the state of files which were removed in the amend
         # to "removed" in the dirstate.
         removedfiles = set(wctx.removed()) & filestoamend
         for f in removedfiles:
             dirstate.drop(f)
 
     return newid
 
 
 def commiteditor(repo, ctx, subs, editform=b''):
     if ctx.description():
         return ctx.description()
     return commitforceeditor(
         repo, ctx, subs, editform=editform, unchangedmessagedetection=True
     )
 
 
 def commitforceeditor(
     repo,
     ctx,
     subs,
     finishdesc=None,
     extramsg=None,
     editform=b'',
     unchangedmessagedetection=False,
 ):
     if not extramsg:
         extramsg = _(b"Leave message empty to abort commit.")
 
     forms = [e for e in editform.split(b'.') if e]
     forms.insert(0, b'changeset')
     templatetext = None
     while forms:
         ref = b'.'.join(forms)
         if repo.ui.config(b'committemplate', ref):
             templatetext = committext = buildcommittemplate(
                 repo, ctx, subs, extramsg, ref
             )
             break
         forms.pop()
     else:
         committext = buildcommittext(repo, ctx, subs, extramsg)
 
     # run editor in the repository root
     olddir = encoding.getcwd()
     os.chdir(repo.root)
 
     # make in-memory changes visible to external process
     tr = repo.currenttransaction()
     repo.dirstate.write(tr)
     pending = tr and tr.writepending() and repo.root
 
     editortext = repo.ui.edit(
         committext,
         ctx.user(),
         ctx.extra(),
         editform=editform,
         pending=pending,
         repopath=repo.path,
         action=b'commit',
     )
     text = editortext
 
     # strip away anything below this special string (used for editors that want
     # to display the diff)
     stripbelow = re.search(_linebelow, text, flags=re.MULTILINE)
     if stripbelow:
         text = text[: stripbelow.start()]
 
     text = re.sub(b"(?m)^HG:.*(\n|$)", b"", text)
     os.chdir(olddir)
 
     if finishdesc:
         text = finishdesc(text)
     if not text.strip():
         raise error.Abort(_(b"empty commit message"))
     if unchangedmessagedetection and editortext == templatetext:
         raise error.Abort(_(b"commit message unchanged"))
 
     return text
 
 
 def buildcommittemplate(repo, ctx, subs, extramsg, ref):
     ui = repo.ui
     spec = formatter.reference_templatespec(ref)
     t = logcmdutil.changesettemplater(ui, repo, spec)
     t.t.cache.update(
         (k, templater.unquotestring(v))
         for k, v in repo.ui.configitems(b'committemplate')
     )
 
     if not extramsg:
         extramsg = b''  # ensure that extramsg is string
 
     ui.pushbuffer()
     t.show(ctx, extramsg=extramsg)
     return ui.popbuffer()
 
 
 def hgprefix(msg):
     return b"\n".join([b"HG: %s" % a for a in msg.split(b"\n") if a])
 
 
 def buildcommittext(repo, ctx, subs, extramsg):
     edittext = []
     modified, added, removed = ctx.modified(), ctx.added(), ctx.removed()
     if ctx.description():
         edittext.append(ctx.description())
     edittext.append(b"")
     edittext.append(b"")  # Empty line between message and comments.
     edittext.append(
         hgprefix(
             _(
                 b"Enter commit message."
                 b"  Lines beginning with 'HG:' are removed."
             )
         )
     )
     edittext.append(hgprefix(extramsg))
     edittext.append(b"HG: --")
     edittext.append(hgprefix(_(b"user: %s") % ctx.user()))
     if ctx.p2():
         edittext.append(hgprefix(_(b"branch merge")))
     if ctx.branch():
         edittext.append(hgprefix(_(b"branch '%s'") % ctx.branch()))
     if bookmarks.isactivewdirparent(repo):
         edittext.append(hgprefix(_(b"bookmark '%s'") % repo._activebookmark))
     edittext.extend([hgprefix(_(b"subrepo %s") % s) for s in subs])
     edittext.extend([hgprefix(_(b"added %s") % f) for f in added])
     edittext.extend([hgprefix(_(b"changed %s") % f) for f in modified])
     edittext.extend([hgprefix(_(b"removed %s") % f) for f in removed])
     if not added and not modified and not removed:
         edittext.append(hgprefix(_(b"no files changed")))
     edittext.append(b"")
 
     return b"\n".join(edittext)
 
 
 def commitstatus(repo, node, branch, bheads=None, opts=None):
     if opts is None:
         opts = {}
     ctx = repo[node]
     parents = ctx.parents()
 
     if (
         not opts.get(b'amend')
         and bheads
         and node not in bheads
         and not any(
             p.node() in bheads and p.branch() == branch for p in parents
         )
     ):
         repo.ui.status(_(b'created new head\n'))
         # The message is not printed for initial roots. For the other
         # changesets, it is printed in the following situations:
         #
         # Par column: for the 2 parents with ...
         #   N: null or no parent
         #   B: parent is on another named branch
         #   C: parent is a regular non head changeset
         #   H: parent was a branch head of the current branch
         # Msg column: whether we print "created new head" message
         # In the following, it is assumed that there already exists some
         # initial branch heads of the current branch, otherwise nothing is
         # printed anyway.
         #
         # Par Msg Comment
         # N N  y  additional topo root
         #
         # B N  y  additional branch root
         # C N  y  additional topo head
         # H N  n  usual case
         #
         # B B  y  weird additional branch root
         # C B  y  branch merge
         # H B  n  merge with named branch
         #
         # C C  y  additional head from merge
         # C H  n  merge with a head
         #
         # H H  n  head merge: head count decreases
 
     if not opts.get(b'close_branch'):
         for r in parents:
             if r.closesbranch() and r.branch() == branch:
                 repo.ui.status(
                     _(b'reopening closed branch head %d\n') % r.rev()
                 )
 
     if repo.ui.debugflag:
         repo.ui.write(
             _(b'committed changeset %d:%s\n') % (ctx.rev(), ctx.hex())
         )
     elif repo.ui.verbose:
         repo.ui.write(_(b'committed changeset %d:%s\n') % (ctx.rev(), ctx))
 
 
 def postcommitstatus(repo, pats, opts):
     return repo.status(match=scmutil.match(repo[None], pats, opts))
 
 
 def revert(ui, repo, ctx, *pats, **opts):
     opts = pycompat.byteskwargs(opts)
     parent, p2 = repo.dirstate.parents()
     node = ctx.node()
 
     mf = ctx.manifest()
     if node == p2:
         parent = p2
 
     # need all matching names in dirstate and manifest of target rev,
     # so have to walk both. do not print errors if files exist in one
     # but not other. in both cases, filesets should be evaluated against
     # workingctx to get consistent result (issue4497). this means 'set:**'
     # cannot be used to select missing files from target rev.
 
     # `names` is a mapping for all elements in working copy and target revision
     # The mapping is in the form:
     #   <abs path in repo> -> (<path from CWD>, <exactly specified by matcher?>)
     names = {}
     uipathfn = scmutil.getuipathfn(repo, legacyrelativevalue=True)
 
     with repo.wlock():
         ## filling of the `names` mapping
         # walk dirstate to fill `names`
 
         interactive = opts.get(b'interactive', False)
         wctx = repo[None]
         m = scmutil.match(wctx, pats, opts)
 
         # we'll need this later
         targetsubs = sorted(s for s in wctx.substate if m(s))
 
         if not m.always():
             matcher = matchmod.badmatch(m, lambda x, y: False)
             for abs in wctx.walk(matcher):
                 names[abs] = m.exact(abs)
 
             # walk target manifest to fill `names`
 
             def badfn(path, msg):
                 if path in names:
                     return
                 if path in ctx.substate:
                     return
                 path_ = path + b'/'
                 for f in names:
                     if f.startswith(path_):
                         return
                 ui.warn(b"%s: %s\n" % (uipathfn(path), msg))
 
             for abs in ctx.walk(matchmod.badmatch(m, badfn)):
                 if abs not in names:
                     names[abs] = m.exact(abs)
 
             # Find status of all file in `names`.
             m = scmutil.matchfiles(repo, names)
 
             changes = repo.status(
                 node1=node, match=m, unknown=True, ignored=True, clean=True
             )
         else:
             changes = repo.status(node1=node, match=m)
             for kind in changes:
                 for abs in kind:
                     names[abs] = m.exact(abs)
 
             m = scmutil.matchfiles(repo, names)
 
         modified = set(changes.modified)
         added = set(changes.added)
         removed = set(changes.removed)
         _deleted = set(changes.deleted)
         unknown = set(changes.unknown)
         unknown.update(changes.ignored)
         clean = set(changes.clean)
         modadded = set()
 
         # We need to account for the state of the file in the dirstate,
         # even when we revert against something else than parent. This will
         # slightly alter the behavior of revert (doing back up or not, delete
         # or just forget etc).
         if parent == node:
             dsmodified = modified
             dsadded = added
             dsremoved = removed
             # store all local modifications, useful later for rename detection
             localchanges = dsmodified | dsadded
             modified, added, removed = set(), set(), set()
         else:
             changes = repo.status(node1=parent, match=m)
             dsmodified = set(changes.modified)
             dsadded = set(changes.added)
             dsremoved = set(changes.removed)
             # store all local modifications, useful later for rename detection
             localchanges = dsmodified | dsadded
 
             # only take into account for removes between wc and target
             clean |= dsremoved - removed
             dsremoved &= removed
             # distinct between dirstate remove and other
             removed -= dsremoved
 
             modadded = added & dsmodified
             added -= modadded
 
             # tell newly modified apart.
             dsmodified &= modified
             dsmodified |= modified & dsadded  # dirstate added may need backup
             modified -= dsmodified
 
             # We need to wait for some post-processing to update this set
             # before making the distinction. The dirstate will be used for
             # that purpose.
             dsadded = added
 
         # in case of merge, files that are actually added can be reported as
         # modified, we need to post process the result
         if p2 != nullid:
             mergeadd = set(dsmodified)
             for path in dsmodified:
                 if path in mf:
                     mergeadd.remove(path)
             dsadded |= mergeadd
             dsmodified -= mergeadd
 
         # if f is a rename, update `names` to also revert the source
         for f in localchanges:
             src = repo.dirstate.copied(f)
             # XXX should we check for rename down to target node?
             if src and src not in names and repo.dirstate[src] == b'r':
                 dsremoved.add(src)
                 names[src] = True
 
         # determine the exact nature of the deleted changesets
         deladded = set(_deleted)
         for path in _deleted:
             if path in mf:
                 deladded.remove(path)
         deleted = _deleted - deladded
 
         # distinguish between file to forget and the other
         added = set()
         for abs in dsadded:
             if repo.dirstate[abs] != b'a':
                 added.add(abs)
         dsadded -= added
 
         for abs in deladded:
             if repo.dirstate[abs] == b'a':
                 dsadded.add(abs)
         deladded -= dsadded
 
         # For files marked as removed, we check if an unknown file is present at
         # the same path. If a such file exists it may need to be backed up.
         # Making the distinction at this stage helps have simpler backup
         # logic.
         removunk = set()
         for abs in removed:
             target = repo.wjoin(abs)
             if os.path.lexists(target):
                 removunk.add(abs)
         removed -= removunk
 
         dsremovunk = set()
         for abs in dsremoved:
             target = repo.wjoin(abs)
             if os.path.lexists(target):
                 dsremovunk.add(abs)
         dsremoved -= dsremovunk
 
         # action to be actually performed by revert
         # (<list of file>, message>) tuple
         actions = {
             b'revert': ([], _(b'reverting %s\n')),
             b'add': ([], _(b'adding %s\n')),
             b'remove': ([], _(b'removing %s\n')),
             b'drop': ([], _(b'removing %s\n')),
             b'forget': ([], _(b'forgetting %s\n')),
             b'undelete': ([], _(b'undeleting %s\n')),
             b'noop': (None, _(b'no changes needed to %s\n')),
             b'unknown': (None, _(b'file not managed: %s\n')),
         }
 
         # "constant" that convey the backup strategy.
         # All set to `discard` if `no-backup` is set do avoid checking
         # no_backup lower in the code.
         # These values are ordered for comparison purposes
         backupinteractive = 3  # do backup if interactively modified
         backup = 2  # unconditionally do backup
         check = 1  # check if the existing file differs from target
         discard = 0  # never do backup
         if opts.get(b'no_backup'):
             backupinteractive = backup = check = discard
         if interactive:
             dsmodifiedbackup = backupinteractive
         else:
             dsmodifiedbackup = backup
         tobackup = set()
 
         backupanddel = actions[b'remove']
         if not opts.get(b'no_backup'):
             backupanddel = actions[b'drop']
 
         disptable = (
             # dispatch table:
             #   file state
             #   action
             #   make backup
             ## Sets that results that will change file on disk
             # Modified compared to target, no local change
             (modified, actions[b'revert'], discard),
             # Modified compared to target, but local file is deleted
             (deleted, actions[b'revert'], discard),
             # Modified compared to target, local change
             (dsmodified, actions[b'revert'], dsmodifiedbackup),
             # Added since target
             (added, actions[b'remove'], discard),
             # Added in working directory
             (dsadded, actions[b'forget'], discard),
             # Added since target, have local modification
             (modadded, backupanddel, backup),
             # Added since target but file is missing in working directory
             (deladded, actions[b'drop'], discard),
             # Removed since  target, before working copy parent
             (removed, actions[b'add'], discard),
             # Same as `removed` but an unknown file exists at the same path
             (removunk, actions[b'add'], check),
             # Removed since targe, marked as such in working copy parent
             (dsremoved, actions[b'undelete'], discard),
             # Same as `dsremoved` but an unknown file exists at the same path
             (dsremovunk, actions[b'undelete'], check),
             ## the following sets does not result in any file changes
             # File with no modification
             (clean, actions[b'noop'], discard),
             # Existing file, not tracked anywhere
             (unknown, actions[b'unknown'], discard),
         )
 
         for abs, exact in sorted(names.items()):
             # target file to be touch on disk (relative to cwd)
             target = repo.wjoin(abs)
             # search the entry in the dispatch table.
             # if the file is in any of these sets, it was touched in the working
             # directory parent and we are sure it needs to be reverted.
             for table, (xlist, msg), dobackup in disptable:
                 if abs not in table:
                     continue
                 if xlist is not None:
                     xlist.append(abs)
                     if dobackup:
                         # If in interactive mode, don't automatically create
                         # .orig files (issue4793)
                         if dobackup == backupinteractive:
                             tobackup.add(abs)
                         elif backup <= dobackup or wctx[abs].cmp(ctx[abs]):
                             absbakname = scmutil.backuppath(ui, repo, abs)
                             bakname = os.path.relpath(
                                 absbakname, start=repo.root
                             )
                             ui.note(
                                 _(b'saving current version of %s as %s\n')
                                 % (uipathfn(abs), uipathfn(bakname))
                             )
                             if not opts.get(b'dry_run'):
                                 if interactive:
                                     util.copyfile(target, absbakname)
                                 else:
                                     util.rename(target, absbakname)
                     if opts.get(b'dry_run'):
                         if ui.verbose or not exact:
                             ui.status(msg % uipathfn(abs))
                 elif exact:
                     ui.warn(msg % uipathfn(abs))
                 break
 
         if not opts.get(b'dry_run'):
             needdata = (b'revert', b'add', b'undelete')
             oplist = [actions[name][0] for name in needdata]
             prefetch = scmutil.prefetchfiles
             matchfiles = scmutil.matchfiles(
                 repo, [f for sublist in oplist for f in sublist]
             )
             prefetch(
                 repo, [(ctx.rev(), matchfiles)],
             )
             match = scmutil.match(repo[None], pats)
             _performrevert(
                 repo,
                 ctx,
                 names,
                 uipathfn,
                 actions,
                 match,
                 interactive,
                 tobackup,
             )
 
         if targetsubs:
             # Revert the subrepos on the revert list
             for sub in targetsubs:
                 try:
                     wctx.sub(sub).revert(
                         ctx.substate[sub], *pats, **pycompat.strkwargs(opts)
                     )
                 except KeyError:
                     raise error.Abort(
                         b"subrepository '%s' does not exist in %s!"
                         % (sub, short(ctx.node()))
                     )
 
 
 def _performrevert(
     repo,
     ctx,
     names,
     uipathfn,
     actions,
     match,
     interactive=False,
     tobackup=None,
 ):
     """function that actually perform all the actions computed for revert
 
     This is an independent function to let extension to plug in and react to
     the imminent revert.
 
     Make sure you have the working directory locked when calling this function.
     """
     parent, p2 = repo.dirstate.parents()
     node = ctx.node()
     excluded_files = []
 
     def checkout(f):
         fc = ctx[f]
         repo.wwrite(f, fc.data(), fc.flags())
 
     def doremove(f):
         try:
             rmdir = repo.ui.configbool(b'experimental', b'removeemptydirs')
             repo.wvfs.unlinkpath(f, rmdir=rmdir)
         except OSError:
             pass
         repo.dirstate.remove(f)
 
     def prntstatusmsg(action, f):
         exact = names[f]
         if repo.ui.verbose or not exact:
             repo.ui.status(actions[action][1] % uipathfn(f))
 
     audit_path = pathutil.pathauditor(repo.root, cached=True)
     for f in actions[b'forget'][0]:
         if interactive:
             choice = repo.ui.promptchoice(
                 _(b"forget added file %s (Yn)?$$ &Yes $$ &No") % uipathfn(f)
             )
             if choice == 0:
                 prntstatusmsg(b'forget', f)
                 repo.dirstate.drop(f)
             else:
                 excluded_files.append(f)
         else:
             prntstatusmsg(b'forget', f)
             repo.dirstate.drop(f)
     for f in actions[b'remove'][0]:
         audit_path(f)
         if interactive:
             choice = repo.ui.promptchoice(
                 _(b"remove added file %s (Yn)?$$ &Yes $$ &No") % uipathfn(f)
             )
             if choice == 0:
                 prntstatusmsg(b'remove', f)
                 doremove(f)
             else:
                 excluded_files.append(f)
         else:
             prntstatusmsg(b'remove', f)
             doremove(f)
     for f in actions[b'drop'][0]:
         audit_path(f)
         prntstatusmsg(b'drop', f)
         repo.dirstate.remove(f)
 
     normal = None
     if node == parent:
         # We're reverting to our parent. If possible, we'd like status
         # to report the file as clean. We have to use normallookup for
         # merges to avoid losing information about merged/dirty files.
         if p2 != nullid:
             normal = repo.dirstate.normallookup
         else:
             normal = repo.dirstate.normal
 
     newlyaddedandmodifiedfiles = set()
     if interactive:
         # Prompt the user for changes to revert
         torevert = [f for f in actions[b'revert'][0] if f not in excluded_files]
         m = scmutil.matchfiles(repo, torevert)
         diffopts = patch.difffeatureopts(
             repo.ui,
             whitespace=True,
             section=b'commands',
             configprefix=b'revert.interactive.',
         )
         diffopts.nodates = True
         diffopts.git = True
         operation = b'apply'
         if node == parent:
             if repo.ui.configbool(
                 b'experimental', b'revert.interactive.select-to-keep'
             ):
                 operation = b'keep'
             else:
                 operation = b'discard'
 
         if operation == b'apply':
             diff = patch.diff(repo, None, ctx.node(), m, opts=diffopts)
         else:
             diff = patch.diff(repo, ctx.node(), None, m, opts=diffopts)
         originalchunks = patch.parsepatch(diff)
 
         try:
 
             chunks, opts = recordfilter(
                 repo.ui, originalchunks, match, operation=operation
             )
             if operation == b'discard':
                 chunks = patch.reversehunks(chunks)
 
         except error.PatchError as err:
             raise error.Abort(_(b'error parsing patch: %s') % err)
 
         # FIXME: when doing an interactive revert of a copy, there's no way of
         # performing a partial revert of the added file, the only option is
         # "remove added file <name> (Yn)?", so we don't need to worry about the
         # alsorestore value. Ideally we'd be able to partially revert
         # copied/renamed files.
         newlyaddedandmodifiedfiles, unusedalsorestore = newandmodified(
             chunks, originalchunks
         )
         if tobackup is None:
             tobackup = set()
         # Apply changes
         fp = stringio()
         # chunks are serialized per file, but files aren't sorted
         for f in sorted({c.header.filename() for c in chunks if ishunk(c)}):
             prntstatusmsg(b'revert', f)
         files = set()
         for c in chunks:
             if ishunk(c):
                 abs = c.header.filename()
                 # Create a backup file only if this hunk should be backed up
                 if c.header.filename() in tobackup:
                     target = repo.wjoin(abs)
                     bakname = scmutil.backuppath(repo.ui, repo, abs)
                     util.copyfile(target, bakname)
                     tobackup.remove(abs)
                 if abs not in files:
                     files.add(abs)
                     if operation == b'keep':
                         checkout(abs)
             c.write(fp)
         dopatch = fp.tell()
         fp.seek(0)
         if dopatch:
             try:
                 patch.internalpatch(repo.ui, repo, fp, 1, eolmode=None)
             except error.PatchError as err:
                 raise error.Abort(pycompat.bytestr(err))
         del fp
     else:
         for f in actions[b'revert'][0]:
             prntstatusmsg(b'revert', f)
             checkout(f)
             if normal:
                 normal(f)
 
     for f in actions[b'add'][0]:
         # Don't checkout modified files, they are already created by the diff
         if f not in newlyaddedandmodifiedfiles:
             prntstatusmsg(b'add', f)
             checkout(f)
             repo.dirstate.add(f)
 
     normal = repo.dirstate.normallookup
     if node == parent and p2 == nullid:
         normal = repo.dirstate.normal
     for f in actions[b'undelete'][0]:
         if interactive:
             choice = repo.ui.promptchoice(
                 _(b"add back removed file %s (Yn)?$$ &Yes $$ &No") % f
             )
             if choice == 0:
                 prntstatusmsg(b'undelete', f)
                 checkout(f)
                 normal(f)
             else:
                 excluded_files.append(f)
         else:
             prntstatusmsg(b'undelete', f)
             checkout(f)
             normal(f)
 
     copied = copies.pathcopies(repo[parent], ctx)
 
     for f in (
         actions[b'add'][0] + actions[b'undelete'][0] + actions[b'revert'][0]
     ):
         if f in copied:
             repo.dirstate.copy(copied[f], f)
 
 
 # a list of (ui, repo, otherpeer, opts, missing) functions called by
 # commands.outgoing.  "missing" is "missing" of the result of
 # "findcommonoutgoing()"
 outgoinghooks = util.hooks()
 
 # a list of (ui, repo) functions called by commands.summary
 summaryhooks = util.hooks()
 
 # a list of (ui, repo, opts, changes) functions called by commands.summary.
 #
 # functions should return tuple of booleans below, if 'changes' is None:
 #  (whether-incomings-are-needed, whether-outgoings-are-needed)
 #
 # otherwise, 'changes' is a tuple of tuples below:
 #  - (sourceurl, sourcebranch, sourcepeer, incoming)
 #  - (desturl,   destbranch,   destpeer,   outgoing)
 summaryremotehooks = util.hooks()
 
 
 def checkunfinished(repo, commit=False, skipmerge=False):
     '''Look for an unfinished multistep operation, like graft, and abort
     if found. It's probably good to check this right before
     bailifchanged().
     '''
     # Check for non-clearable states first, so things like rebase will take
     # precedence over update.
     for state in statemod._unfinishedstates:
         if (
             state._clearable
             or (commit and state._allowcommit)
             or state._reportonly
         ):
             continue
         if state.isunfinished(repo):
             raise error.Abort(state.msg(), hint=state.hint())
 
     for s in statemod._unfinishedstates:
         if (
             not s._clearable
             or (commit and s._allowcommit)
             or (s._opname == b'merge' and skipmerge)
             or s._reportonly
         ):
             continue
         if s.isunfinished(repo):
             raise error.Abort(s.msg(), hint=s.hint())
 
 
 def clearunfinished(repo):
     '''Check for unfinished operations (as above), and clear the ones
     that are clearable.
     '''
     for state in statemod._unfinishedstates:
         if state._reportonly:
             continue
         if not state._clearable and state.isunfinished(repo):
             raise error.Abort(state.msg(), hint=state.hint())
 
     for s in statemod._unfinishedstates:
         if s._opname == b'merge' or state._reportonly:
             continue
         if s._clearable and s.isunfinished(repo):
             util.unlink(repo.vfs.join(s._fname))
 
 
 def getunfinishedstate(repo):
     ''' Checks for unfinished operations and returns statecheck object
         for it'''
     for state in statemod._unfinishedstates:
         if state.isunfinished(repo):
             return state
     return None
 
 
 def howtocontinue(repo):
     '''Check for an unfinished operation and return the command to finish
     it.
 
     statemod._unfinishedstates list is checked for an unfinished operation
     and the corresponding message to finish it is generated if a method to
     continue is supported by the operation.
 
     Returns a (msg, warning) tuple. 'msg' is a string and 'warning' is
     a boolean.
     '''
     contmsg = _(b"continue: %s")
     for state in statemod._unfinishedstates:
         if not state._continueflag:
             continue
         if state.isunfinished(repo):
             return contmsg % state.continuemsg(), True
     if repo[None].dirty(missing=True, merge=False, branch=False):
         return contmsg % _(b"hg commit"), False
     return None, None
 
 
 def checkafterresolved(repo):
     '''Inform the user about the next action after completing hg resolve
 
     If there's a an unfinished operation that supports continue flag,
     howtocontinue will yield repo.ui.warn as the reporter.
 
     Otherwise, it will yield repo.ui.note.
     '''
     msg, warning = howtocontinue(repo)
     if msg is not None:
         if warning:
             repo.ui.warn(b"%s\n" % msg)
         else:
             repo.ui.note(b"%s\n" % msg)
 
 
 def wrongtooltocontinue(repo, task):
     '''Raise an abort suggesting how to properly continue if there is an
     active task.
 
     Uses howtocontinue() to find the active task.
 
     If there's no task (repo.ui.note for 'hg commit'), it does not offer
     a hint.
     '''
     after = howtocontinue(repo)
     hint = None
     if after[1]:
         hint = after[0]
     raise error.Abort(_(b'no %s in progress') % task, hint=hint)
 
 
 def abortgraft(ui, repo, graftstate):
     """abort the interrupted graft and rollbacks to the state before interrupted
     graft"""
     if not graftstate.exists():
         raise error.Abort(_(b"no interrupted graft to abort"))
     statedata = readgraftstate(repo, graftstate)
     newnodes = statedata.get(b'newnodes')
     if newnodes is None:
         # and old graft state which does not have all the data required to abort
         # the graft
         raise error.Abort(_(b"cannot abort using an old graftstate"))
 
     # changeset from which graft operation was started
     if len(newnodes) > 0:
         startctx = repo[newnodes[0]].p1()
     else:
         startctx = repo[b'.']
     # whether to strip or not
     cleanup = False
 
     if newnodes:
         newnodes = [repo[r].rev() for r in newnodes]
         cleanup = True
         # checking that none of the newnodes turned public or is public
         immutable = [c for c in newnodes if not repo[c].mutable()]
         if immutable:
             repo.ui.warn(
                 _(b"cannot clean up public changesets %s\n")
                 % b', '.join(bytes(repo[r]) for r in immutable),
                 hint=_(b"see 'hg help phases' for details"),
             )
             cleanup = False
 
         # checking that no new nodes are created on top of grafted revs
         desc = set(repo.changelog.descendants(newnodes))
         if desc - set(newnodes):
             repo.ui.warn(
                 _(
                     b"new changesets detected on destination "
                     b"branch, can't strip\n"
                 )
             )
             cleanup = False
 
         if cleanup:
             with repo.wlock(), repo.lock():
                 mergemod.clean_update(startctx)
                 # stripping the new nodes created
                 strippoints = [
                     c.node() for c in repo.set(b"roots(%ld)", newnodes)
                 ]
                 repair.strip(repo.ui, repo, strippoints, backup=False)
 
     if not cleanup:
         # we don't update to the startnode if we can't strip
         startctx = repo[b'.']
         mergemod.clean_update(startctx)
 
     ui.status(_(b"graft aborted\n"))
     ui.status(_(b"working directory is now at %s\n") % startctx.hex()[:12])
     graftstate.delete()
     return 0
 
 
 def readgraftstate(repo, graftstate):
     # type: (Any, statemod.cmdstate) -> Dict[bytes, Any]
     """read the graft state file and return a dict of the data stored in it"""
     try:
         return graftstate.read()
     except error.CorruptedState:
         nodes = repo.vfs.read(b'graftstate').splitlines()
         return {b'nodes': nodes}
 
 
 def hgabortgraft(ui, repo):
     """ abort logic for aborting graft using 'hg abort'"""
     with repo.wlock():
         graftstate = statemod.cmdstate(repo, b'graftstate')
         return abortgraft(ui, repo, graftstate)

mercurial/logcmdutil.py

@@ -1,1212 +1,1210
 # logcmdutil.py - utility for log-like commands
 #
 # Copyright 2005-2007 Matt Mackall <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
 from __future__ import absolute_import
 
 import itertools
 import os
 import posixpath
 
 from .i18n import _
 from .node import (
     nullid,
     wdirid,
     wdirrev,
 )
 
 from .thirdparty import attr
 
 from . import (
     dagop,
     error,
     formatter,
     graphmod,
     match as matchmod,
     mdiff,
     patch,
     pathutil,
     pycompat,
     revset,
     revsetlang,
     scmutil,
     smartset,
     templatekw,
     templater,
     util,
 )
 from .utils import (
     dateutil,
     stringutil,
 )
 
 
 if pycompat.TYPE_CHECKING:
     from typing import (
         Any,
         Callable,
         Dict,
         List,
         Optional,
         Tuple,
     )
 
     for t in (Any, Callable, Dict, List, Optional, Tuple):
         assert t
 
 
 def getlimit(opts):
     """get the log limit according to option -l/--limit"""
     limit = opts.get(b'limit')
     if limit:
         try:
             limit = int(limit)
         except ValueError:
             raise error.Abort(_(b'limit must be a positive integer'))
         if limit <= 0:
             raise error.Abort(_(b'limit must be positive'))
     else:
         limit = None
     return limit
 
 
 def diffordiffstat(
     ui,
     repo,
     diffopts,
     ctx1,
     ctx2,
     match,
     changes=None,
     stat=False,
     fp=None,
     graphwidth=0,
     prefix=b'',
     root=b'',
     listsubrepos=False,
     hunksfilterfn=None,
 ):
     '''show diff or diffstat.'''
     if root:
         relroot = pathutil.canonpath(repo.root, repo.getcwd(), root)
     else:
         relroot = b''
     copysourcematch = None
 
     def compose(f, g):
         return lambda x: f(g(x))
 
     def pathfn(f):
         return posixpath.join(prefix, f)
 
     if relroot != b'':
         # XXX relative roots currently don't work if the root is within a
         # subrepo
         uipathfn = scmutil.getuipathfn(repo, legacyrelativevalue=True)
         uirelroot = uipathfn(pathfn(relroot))
         relroot += b'/'
         for matchroot in match.files():
             if not matchroot.startswith(relroot):
                 ui.warn(
                     _(b'warning: %s not inside relative root %s\n')
                     % (uipathfn(pathfn(matchroot)), uirelroot)
                 )
 
         relrootmatch = scmutil.match(ctx2, pats=[relroot], default=b'path')
         match = matchmod.intersectmatchers(match, relrootmatch)
         copysourcematch = relrootmatch
 
         checkroot = repo.ui.configbool(
             b'devel', b'all-warnings'
         ) or repo.ui.configbool(b'devel', b'check-relroot')
 
         def relrootpathfn(f):
             if checkroot and not f.startswith(relroot):
                 raise AssertionError(
                     b"file %s doesn't start with relroot %s" % (f, relroot)
                 )
             return f[len(relroot) :]
 
         pathfn = compose(relrootpathfn, pathfn)
 
     if stat:
         diffopts = diffopts.copy(context=0, noprefix=False)
         width = 80
         if not ui.plain():
             width = ui.termwidth() - graphwidth
         # If an explicit --root was given, don't respect ui.relative-paths
         if not relroot:
             pathfn = compose(scmutil.getuipathfn(repo), pathfn)
 
     chunks = ctx2.diff(
         ctx1,
         match,
         changes,
         opts=diffopts,
         pathfn=pathfn,
         copysourcematch=copysourcematch,
         hunksfilterfn=hunksfilterfn,
     )
 
     if fp is not None or ui.canwritewithoutlabels():
         out = fp or ui
         if stat:
             chunks = [patch.diffstat(util.iterlines(chunks), width=width)]
         for chunk in util.filechunkiter(util.chunkbuffer(chunks)):
             out.write(chunk)
     else:
         if stat:
             chunks = patch.diffstatui(util.iterlines(chunks), width=width)
         else:
             chunks = patch.difflabel(
                 lambda chunks, **kwargs: chunks, chunks, opts=diffopts
             )
         if ui.canbatchlabeledwrites():
 
             def gen():
                 for chunk, label in chunks:
                     yield ui.label(chunk, label=label)
 
             for chunk in util.filechunkiter(util.chunkbuffer(gen())):
                 ui.write(chunk)
         else:
             for chunk, label in chunks:
                 ui.write(chunk, label=label)
 
     node2 = ctx2.node()
     for subpath, sub in scmutil.itersubrepos(ctx1, ctx2):
         tempnode2 = node2
         try:
             if node2 is not None:
                 tempnode2 = ctx2.substate[subpath][1]
         except KeyError:
             # A subrepo that existed in node1 was deleted between node1 and
             # node2 (inclusive). Thus, ctx2's substate won't contain that
             # subpath. The best we can do is to ignore it.
             tempnode2 = None
         submatch = matchmod.subdirmatcher(subpath, match)
         subprefix = repo.wvfs.reljoin(prefix, subpath)
         if listsubrepos or match.exact(subpath) or any(submatch.files()):
             sub.diff(
                 ui,
                 diffopts,
                 tempnode2,
                 submatch,
                 changes=changes,
                 stat=stat,
                 fp=fp,
                 prefix=subprefix,
             )
 
 
 class changesetdiffer(object):
     """Generate diff of changeset with pre-configured filtering functions"""
 
     def _makefilematcher(self, ctx):
         return scmutil.matchall(ctx.repo())
 
     def _makehunksfilter(self, ctx):
         return None
 
     def showdiff(self, ui, ctx, diffopts, graphwidth=0, stat=False):
         diffordiffstat(
             ui,
             ctx.repo(),
             diffopts,
             ctx.p1(),
             ctx,
             match=self._makefilematcher(ctx),
             stat=stat,
             graphwidth=graphwidth,
             hunksfilterfn=self._makehunksfilter(ctx),
         )
 
 
 def changesetlabels(ctx):
     labels = [b'log.changeset', b'changeset.%s' % ctx.phasestr()]
     if ctx.obsolete():
         labels.append(b'changeset.obsolete')
     if ctx.isunstable():
         labels.append(b'changeset.unstable')
         for instability in ctx.instabilities():
             labels.append(b'instability.%s' % instability)
     return b' '.join(labels)
 
 
 class changesetprinter(object):
     '''show changeset information when templating not requested.'''
 
     def __init__(self, ui, repo, differ=None, diffopts=None, buffered=False):
         self.ui = ui
         self.repo = repo
         self.buffered = buffered
         self._differ = differ or changesetdiffer()
         self._diffopts = patch.diffallopts(ui, diffopts)
         self._includestat = diffopts and diffopts.get(b'stat')
         self._includediff = diffopts and diffopts.get(b'patch')
         self.header = {}
         self.hunk = {}
         self.lastheader = None
         self.footer = None
         self._columns = templatekw.getlogcolumns()
 
     def flush(self, ctx):
         rev = ctx.rev()
         if rev in self.header:
             h = self.header[rev]
             if h != self.lastheader:
                 self.lastheader = h
                 self.ui.write(h)
             del self.header[rev]
         if rev in self.hunk:
             self.ui.write(self.hunk[rev])
             del self.hunk[rev]
 
     def close(self):
         if self.footer:
             self.ui.write(self.footer)
 
     def show(self, ctx, copies=None, **props):
         props = pycompat.byteskwargs(props)
         if self.buffered:
             self.ui.pushbuffer(labeled=True)
             self._show(ctx, copies, props)
             self.hunk[ctx.rev()] = self.ui.popbuffer()
         else:
             self._show(ctx, copies, props)
 
     def _show(self, ctx, copies, props):
         '''show a single changeset or file revision'''
         changenode = ctx.node()
         graphwidth = props.get(b'graphwidth', 0)
 
         if self.ui.quiet:
             self.ui.write(
                 b"%s\n" % scmutil.formatchangeid(ctx), label=b'log.node'
             )
             return
 
         columns = self._columns
         self.ui.write(
             columns[b'changeset'] % scmutil.formatchangeid(ctx),
             label=changesetlabels(ctx),
         )
 
         # branches are shown first before any other names due to backwards
         # compatibility
         branch = ctx.branch()
         # don't show the default branch name
         if branch != b'default':
             self.ui.write(columns[b'branch'] % branch, label=b'log.branch')
 
         for nsname, ns in pycompat.iteritems(self.repo.names):
             # branches has special logic already handled above, so here we just
             # skip it
             if nsname == b'branches':
                 continue
             # we will use the templatename as the color name since those two
             # should be the same
             for name in ns.names(self.repo, changenode):
                 self.ui.write(ns.logfmt % name, label=b'log.%s' % ns.colorname)
         if self.ui.debugflag:
             self.ui.write(
                 columns[b'phase'] % ctx.phasestr(), label=b'log.phase'
             )
         for pctx in scmutil.meaningfulparents(self.repo, ctx):
             label = b'log.parent changeset.%s' % pctx.phasestr()
             self.ui.write(
                 columns[b'parent'] % scmutil.formatchangeid(pctx), label=label
             )
 
         if self.ui.debugflag:
             mnode = ctx.manifestnode()
             if mnode is None:
                 mnode = wdirid
                 mrev = wdirrev
             else:
                 mrev = self.repo.manifestlog.rev(mnode)
             self.ui.write(
                 columns[b'manifest']
                 % scmutil.formatrevnode(self.ui, mrev, mnode),
                 label=b'ui.debug log.manifest',
             )
         self.ui.write(columns[b'user'] % ctx.user(), label=b'log.user')
         self.ui.write(
             columns[b'date'] % dateutil.datestr(ctx.date()), label=b'log.date'
         )
 
         if ctx.isunstable():
             instabilities = ctx.instabilities()
             self.ui.write(
                 columns[b'instability'] % b', '.join(instabilities),
                 label=b'log.instability',
             )
 
         elif ctx.obsolete():
             self._showobsfate(ctx)
 
         self._exthook(ctx)
 
         if self.ui.debugflag:
             files = ctx.p1().status(ctx)
             for key, value in zip(
                 [b'files', b'files+', b'files-'],
                 [files.modified, files.added, files.removed],
             ):
                 if value:
                     self.ui.write(
                         columns[key] % b" ".join(value),
                         label=b'ui.debug log.files',
                     )
         elif ctx.files() and self.ui.verbose:
             self.ui.write(
                 columns[b'files'] % b" ".join(ctx.files()),
                 label=b'ui.note log.files',
             )
         if copies and self.ui.verbose:
             copies = [b'%s (%s)' % c for c in copies]
             self.ui.write(
                 columns[b'copies'] % b' '.join(copies),
                 label=b'ui.note log.copies',
             )
 
         extra = ctx.extra()
         if extra and self.ui.debugflag:
             for key, value in sorted(extra.items()):
                 self.ui.write(
                     columns[b'extra'] % (key, stringutil.escapestr(value)),
                     label=b'ui.debug log.extra',
                 )
 
         description = ctx.description().strip()
         if description:
             if self.ui.verbose:
                 self.ui.write(
                     _(b"description:\n"), label=b'ui.note log.description'
                 )
                 self.ui.write(description, label=b'ui.note log.description')
                 self.ui.write(b"\n\n")
             else:
                 self.ui.write(
                     columns[b'summary'] % description.splitlines()[0],
                     label=b'log.summary',
                 )
         self.ui.write(b"\n")
 
         self._showpatch(ctx, graphwidth)
 
     def _showobsfate(self, ctx):
         # TODO: do not depend on templater
         tres = formatter.templateresources(self.repo.ui, self.repo)
         t = formatter.maketemplater(
             self.repo.ui,
             b'{join(obsfate, "\n")}',
             defaults=templatekw.keywords,
             resources=tres,
         )
         obsfate = t.renderdefault({b'ctx': ctx}).splitlines()
 
         if obsfate:
             for obsfateline in obsfate:
                 self.ui.write(
                     self._columns[b'obsolete'] % obsfateline,
                     label=b'log.obsfate',
                 )
 
     def _exthook(self, ctx):
         '''empty method used by extension as a hook point
         '''
 
     def _showpatch(self, ctx, graphwidth=0):
         if self._includestat:
             self._differ.showdiff(
                 self.ui, ctx, self._diffopts, graphwidth, stat=True
             )
         if self._includestat and self._includediff:
             self.ui.write(b"\n")
         if self._includediff:
             self._differ.showdiff(
                 self.ui, ctx, self._diffopts, graphwidth, stat=False
             )
         if self._includestat or self._includediff:
             self.ui.write(b"\n")
 
 
 class changesetformatter(changesetprinter):
     """Format changeset information by generic formatter"""
 
     def __init__(
         self, ui, repo, fm, differ=None, diffopts=None, buffered=False
     ):
         changesetprinter.__init__(self, ui, repo, differ, diffopts, buffered)
         self._diffopts = patch.difffeatureopts(ui, diffopts, git=True)
         self._fm = fm
 
     def close(self):
         self._fm.end()
 
     def _show(self, ctx, copies, props):
         '''show a single changeset or file revision'''
         fm = self._fm
         fm.startitem()
         fm.context(ctx=ctx)
         fm.data(rev=scmutil.intrev(ctx), node=fm.hexfunc(scmutil.binnode(ctx)))
 
         datahint = fm.datahint()
         if self.ui.quiet and not datahint:
             return
 
         fm.data(
             branch=ctx.branch(),
             phase=ctx.phasestr(),
             user=ctx.user(),
             date=fm.formatdate(ctx.date()),
             desc=ctx.description(),
             bookmarks=fm.formatlist(ctx.bookmarks(), name=b'bookmark'),
             tags=fm.formatlist(ctx.tags(), name=b'tag'),
             parents=fm.formatlist(
                 [fm.hexfunc(c.node()) for c in ctx.parents()], name=b'node'
             ),
         )
 
         if self.ui.debugflag or b'manifest' in datahint:
             fm.data(manifest=fm.hexfunc(ctx.manifestnode() or wdirid))
         if self.ui.debugflag or b'extra' in datahint:
             fm.data(extra=fm.formatdict(ctx.extra()))
 
         if (
             self.ui.debugflag
             or b'modified' in datahint
             or b'added' in datahint
             or b'removed' in datahint
         ):
             files = ctx.p1().status(ctx)
             fm.data(
                 modified=fm.formatlist(files.modified, name=b'file'),
                 added=fm.formatlist(files.added, name=b'file'),
                 removed=fm.formatlist(files.removed, name=b'file'),
             )
 
         verbose = not self.ui.debugflag and self.ui.verbose
         if verbose or b'files' in datahint:
             fm.data(files=fm.formatlist(ctx.files(), name=b'file'))
         if verbose and copies or b'copies' in datahint:
             fm.data(
                 copies=fm.formatdict(copies or {}, key=b'name', value=b'source')
             )
 
         if self._includestat or b'diffstat' in datahint:
             self.ui.pushbuffer()
             self._differ.showdiff(self.ui, ctx, self._diffopts, stat=True)
             fm.data(diffstat=self.ui.popbuffer())
         if self._includediff or b'diff' in datahint:
             self.ui.pushbuffer()
             self._differ.showdiff(self.ui, ctx, self._diffopts, stat=False)
             fm.data(diff=self.ui.popbuffer())
 
 
 class changesettemplater(changesetprinter):
     '''format changeset information.
 
     Note: there are a variety of convenience functions to build a
     changesettemplater for common cases. See functions such as:
     maketemplater, changesetdisplayer, buildcommittemplate, or other
     functions that use changesest_templater.
     '''
 
     # Arguments before "buffered" used to be positional. Consider not
     # adding/removing arguments before "buffered" to not break callers.
     def __init__(
         self, ui, repo, tmplspec, differ=None, diffopts=None, buffered=False
     ):
         changesetprinter.__init__(self, ui, repo, differ, diffopts, buffered)
         # tres is shared with _graphnodeformatter()
         self._tresources = tres = formatter.templateresources(ui, repo)
         self.t = formatter.loadtemplater(
             ui,
             tmplspec,
             defaults=templatekw.keywords,
             resources=tres,
             cache=templatekw.defaulttempl,
         )
         self._counter = itertools.count()
 
         self._tref = tmplspec.ref
         self._parts = {
             b'header': b'',
             b'footer': b'',
             tmplspec.ref: tmplspec.ref,
             b'docheader': b'',
             b'docfooter': b'',
             b'separator': b'',
         }
         if tmplspec.mapfile:
             # find correct templates for current mode, for backward
             # compatibility with 'log -v/-q/--debug' using a mapfile
             tmplmodes = [
                 (True, b''),
                 (self.ui.verbose, b'_verbose'),
                 (self.ui.quiet, b'_quiet'),
                 (self.ui.debugflag, b'_debug'),
             ]
             for mode, postfix in tmplmodes:
                 for t in self._parts:
                     cur = t + postfix
                     if mode and cur in self.t:
                         self._parts[t] = cur
         else:
             partnames = [p for p in self._parts.keys() if p != tmplspec.ref]
             m = formatter.templatepartsmap(tmplspec, self.t, partnames)
             self._parts.update(m)
 
         if self._parts[b'docheader']:
             self.ui.write(self.t.render(self._parts[b'docheader'], {}))
 
     def close(self):
         if self._parts[b'docfooter']:
             if not self.footer:
                 self.footer = b""
             self.footer += self.t.render(self._parts[b'docfooter'], {})
         return super(changesettemplater, self).close()
 
     def _show(self, ctx, copies, props):
         '''show a single changeset or file revision'''
         props = props.copy()
         props[b'ctx'] = ctx
         props[b'index'] = index = next(self._counter)
         props[b'revcache'] = {b'copies': copies}
         graphwidth = props.get(b'graphwidth', 0)
 
         # write separator, which wouldn't work well with the header part below
         # since there's inherently a conflict between header (across items) and
         # separator (per item)
         if self._parts[b'separator'] and index > 0:
             self.ui.write(self.t.render(self._parts[b'separator'], {}))
 
         # write header
         if self._parts[b'header']:
             h = self.t.render(self._parts[b'header'], props)
             if self.buffered:
                 self.header[ctx.rev()] = h
             else:
                 if self.lastheader != h:
                     self.lastheader = h
                     self.ui.write(h)
 
         # write changeset metadata, then patch if requested
         key = self._parts[self._tref]
         self.ui.write(self.t.render(key, props))
         self._exthook(ctx)
         self._showpatch(ctx, graphwidth)
 
         if self._parts[b'footer']:
             if not self.footer:
                 self.footer = self.t.render(self._parts[b'footer'], props)
 
 
 def templatespec(tmpl, mapfile):
     assert not (tmpl and mapfile)
     if mapfile:
         return formatter.mapfile_templatespec(b'changeset', mapfile)
     else:
         return formatter.literal_templatespec(tmpl)
 
 
 def _lookuptemplate(ui, tmpl, style):
     """Find the template matching the given template spec or style
 
     See formatter.lookuptemplate() for details.
     """
 
     # ui settings
     if not tmpl and not style:  # template are stronger than style
         tmpl = ui.config(b'ui', b'logtemplate')
         if tmpl:
             return formatter.literal_templatespec(templater.unquotestring(tmpl))
         else:
             style = util.expandpath(ui.config(b'ui', b'style'))
 
     if not tmpl and style:
         mapfile = style
         fp = None
         if not os.path.split(mapfile)[0]:
             (mapname, fp) = templater.try_open_template(
                 b'map-cmdline.' + mapfile
             ) or templater.try_open_template(mapfile)
             if mapname:
                 mapfile = mapname
         return formatter.mapfile_templatespec(b'changeset', mapfile, fp)
 
     return formatter.lookuptemplate(ui, b'changeset', tmpl)
 
 
 def maketemplater(ui, repo, tmpl, buffered=False):
     """Create a changesettemplater from a literal template 'tmpl'
     byte-string."""
     spec = formatter.literal_templatespec(tmpl)
     return changesettemplater(ui, repo, spec, buffered=buffered)
 
 
 def changesetdisplayer(ui, repo, opts, differ=None, buffered=False):
     """show one changeset using template or regular display.
 
     Display format will be the first non-empty hit of:
     1. option 'template'
     2. option 'style'
     3. [ui] setting 'logtemplate'
     4. [ui] setting 'style'
     If all of these values are either the unset or the empty string,
     regular display via changesetprinter() is done.
     """
     postargs = (differ, opts, buffered)
     spec = _lookuptemplate(ui, opts.get(b'template'), opts.get(b'style'))
 
     # machine-readable formats have slightly different keyword set than
     # plain templates, which are handled by changesetformatter.
     # note that {b'pickle', b'debug'} can also be added to the list if needed.
     if spec.ref in {b'cbor', b'json'}:
         fm = ui.formatter(b'log', opts)
         return changesetformatter(ui, repo, fm, *postargs)
 
     if not spec.ref and not spec.tmpl and not spec.mapfile:
         return changesetprinter(ui, repo, *postargs)
 
     return changesettemplater(ui, repo, spec, *postargs)
 
 
 @attr.s
 class walkopts(object):
     """Options to configure a set of revisions and file matcher factory
     to scan revision/file history
     """
 
     # raw command-line parameters, which a matcher will be built from
     pats = attr.ib()  # type: List[bytes]
     opts = attr.ib()  # type: Dict[bytes, Any]
 
     # a list of revset expressions to be traversed; if follow, it specifies
     # the start revisions
     revspec = attr.ib()  # type: List[bytes]
 
     # miscellaneous queries to filter revisions (see "hg help log" for details)
     branches = attr.ib(default=attr.Factory(list))  # type: List[bytes]
     date = attr.ib(default=None)  # type: Optional[bytes]
     keywords = attr.ib(default=attr.Factory(list))  # type: List[bytes]
     no_merges = attr.ib(default=False)  # type: bool
     only_merges = attr.ib(default=False)  # type: bool
     prune_ancestors = attr.ib(default=attr.Factory(list))  # type: List[bytes]
     users = attr.ib(default=attr.Factory(list))  # type: List[bytes]
 
     # miscellaneous matcher arguments
     include_pats = attr.ib(default=attr.Factory(list))  # type: List[bytes]
     exclude_pats = attr.ib(default=attr.Factory(list))  # type: List[bytes]
 
     # 0: no follow, 1: follow first, 2: follow both parents
     follow = attr.ib(default=0)  # type: int
 
     # do not attempt filelog-based traversal, which may be fast but cannot
     # include revisions where files were removed
     force_changelog_traversal = attr.ib(default=False)  # type: bool
 
     # filter revisions by file patterns, which should be disabled only if
     # you want to include revisions where files were unmodified
     filter_revisions_by_pats = attr.ib(default=True)  # type: bool
 
     # sort revisions prior to traversal: 'desc', 'topo', or None
     sort_revisions = attr.ib(default=None)  # type: Optional[bytes]
 
     # limit number of changes displayed; None means unlimited
     limit = attr.ib(default=None)  # type: Optional[int]
 
 
 def parseopts(ui, pats, opts):
     # type: (Any, List[bytes], Dict[bytes, Any]) -> walkopts
     """Parse log command options into walkopts
 
     The returned walkopts will be passed in to getrevs() or makewalker().
     """
     if opts.get(b'follow_first'):
         follow = 1
     elif opts.get(b'follow'):
         follow = 2
     else:
         follow = 0
 
     if opts.get(b'graph'):
         if ui.configbool(b'experimental', b'log.topo'):
             sort_revisions = b'topo'
         else:
             sort_revisions = b'desc'
     else:
         sort_revisions = None
 
     return walkopts(
         pats=pats,
         opts=opts,
         revspec=opts.get(b'rev', []),
         # branch and only_branch are really aliases and must be handled at
         # the same time
         branches=opts.get(b'branch', []) + opts.get(b'only_branch', []),
         date=opts.get(b'date'),
         keywords=opts.get(b'keyword', []),
         no_merges=bool(opts.get(b'no_merges')),
         only_merges=bool(opts.get(b'only_merges')),
         prune_ancestors=opts.get(b'prune', []),
         users=opts.get(b'user', []),
         include_pats=opts.get(b'include', []),
         exclude_pats=opts.get(b'exclude', []),
         follow=follow,
         force_changelog_traversal=bool(opts.get(b'removed')),
         sort_revisions=sort_revisions,
         limit=getlimit(opts),
     )
 
 
 def _makematcher(repo, revs, wopts):
     """Build matcher and expanded patterns from log options
 
     If --follow, revs are the revisions to follow from.
 
     Returns (match, pats, slowpath) where
     - match: a matcher built from the given pats and -I/-X opts
     - pats: patterns used (globs are expanded on Windows)
     - slowpath: True if patterns aren't as simple as scanning filelogs
     """
     # pats/include/exclude are passed to match.match() directly in
-    # _matchfiles() revset but walkchangerevs() builds its matcher with
-    # scmutil.match(). The difference is input pats are globbed on
+    # _matchfiles() revset, but a log-like command should build its matcher
+    # with scmutil.match(). The difference is input pats are globbed on
     # platforms without shell expansion (windows).
     wctx = repo[None]
     match, pats = scmutil.matchandpats(wctx, wopts.pats, wopts.opts)
     slowpath = match.anypats() or (
         not match.always() and wopts.force_changelog_traversal
     )
     if not slowpath:
         if wopts.follow and wopts.revspec:
             # There may be the case that a path doesn't exist in some (but
             # not all) of the specified start revisions, but let's consider
             # the path is valid. Missing files will be warned by the matcher.
             startctxs = [repo[r] for r in revs]
             for f in match.files():
                 found = False
                 for c in startctxs:
                     if f in c:
                         found = True
                     elif c.hasdir(f):
                         # If a directory exists in any of the start revisions,
                         # take the slow path.
                         found = slowpath = True
                 if not found:
                     raise error.Abort(
                         _(
                             b'cannot follow file not in any of the specified '
                             b'revisions: "%s"'
                         )
                         % f
                     )
         elif wopts.follow:
             for f in match.files():
                 if f not in wctx:
                     # If the file exists, it may be a directory, so let it
                     # take the slow path.
                     if os.path.exists(repo.wjoin(f)):
                         slowpath = True
                         continue
                     else:
                         raise error.Abort(
                             _(
                                 b'cannot follow file not in parent '
                                 b'revision: "%s"'
                             )
                             % f
                         )
                 filelog = repo.file(f)
                 if not filelog:
                     # A file exists in wdir but not in history, which means
                     # the file isn't committed yet.
                     raise error.Abort(
                         _(b'cannot follow nonexistent file: "%s"') % f
                     )
         else:
             for f in match.files():
                 filelog = repo.file(f)
                 if not filelog:
                     # A zero count may be a directory or deleted file, so
                     # try to find matching entries on the slow path.
                     slowpath = True
 
         # We decided to fall back to the slowpath because at least one
         # of the paths was not a file. Check to see if at least one of them
         # existed in history - in that case, we'll continue down the
         # slowpath; otherwise, we can turn off the slowpath
         if slowpath:
             for path in match.files():
                 if path == b'.' or path in repo.store:
                     break
             else:
                 slowpath = False
 
     return match, pats, slowpath
 
 
 def _fileancestors(repo, revs, match, followfirst):
     fctxs = []
     for r in revs:
         ctx = repo[r]
         fctxs.extend(ctx[f].introfilectx() for f in ctx.walk(match))
 
     # When displaying a revision with --patch --follow FILE, we have
     # to know which file of the revision must be diffed. With
     # --follow, we want the names of the ancestors of FILE in the
     # revision, stored in "fcache". "fcache" is populated as a side effect
     # of the graph traversal.
     fcache = {}
 
     def filematcher(ctx):
         return scmutil.matchfiles(repo, fcache.get(scmutil.intrev(ctx), []))
 
     def revgen():
         for rev, cs in dagop.filectxancestors(fctxs, followfirst=followfirst):
             fcache[rev] = [c.path() for c in cs]
             yield rev
 
     return smartset.generatorset(revgen(), iterasc=False), filematcher
 
 
 def _makenofollowfilematcher(repo, pats, opts):
     '''hook for extensions to override the filematcher for non-follow cases'''
     return None
 
 
 _opt2logrevset = {
     b'no_merges': (b'not merge()', None),
     b'only_merges': (b'merge()', None),
     b'_matchfiles': (None, b'_matchfiles(%ps)'),
     b'date': (b'date(%s)', None),
     b'branch': (b'branch(%s)', b'%lr'),
     b'_patslog': (b'filelog(%s)', b'%lr'),
     b'keyword': (b'keyword(%s)', b'%lr'),
     b'prune': (b'ancestors(%s)', b'not %lr'),
     b'user': (b'user(%s)', b'%lr'),
 }
 
 
 def _makerevset(repo, wopts, slowpath):
     """Return a revset string built from log options and file patterns"""
     opts = {
         b'branch': [repo.lookupbranch(b) for b in wopts.branches],
         b'date': wopts.date,
         b'keyword': wopts.keywords,
         b'no_merges': wopts.no_merges,
         b'only_merges': wopts.only_merges,
         b'prune': wopts.prune_ancestors,
         b'user': wopts.users,
     }
 
     if wopts.filter_revisions_by_pats and slowpath:
-        # See walkchangerevs() slow path.
-        #
         # pats/include/exclude cannot be represented as separate
         # revset expressions as their filtering logic applies at file
         # level. For instance "-I a -X b" matches a revision touching
         # "a" and "b" while "file(a) and not file(b)" does
         # not. Besides, filesets are evaluated against the working
         # directory.
         matchargs = [b'r:', b'd:relpath']
         for p in wopts.pats:
             matchargs.append(b'p:' + p)
         for p in wopts.include_pats:
             matchargs.append(b'i:' + p)
         for p in wopts.exclude_pats:
             matchargs.append(b'x:' + p)
         opts[b'_matchfiles'] = matchargs
     elif wopts.filter_revisions_by_pats and not wopts.follow:
         opts[b'_patslog'] = list(wopts.pats)
 
     expr = []
     for op, val in sorted(pycompat.iteritems(opts)):
         if not val:
             continue
         revop, listop = _opt2logrevset[op]
         if revop and b'%' not in revop:
             expr.append(revop)
         elif not listop:
             expr.append(revsetlang.formatspec(revop, val))
         else:
             if revop:
                 val = [revsetlang.formatspec(revop, v) for v in val]
             expr.append(revsetlang.formatspec(listop, val))
 
     if expr:
         expr = b'(' + b' and '.join(expr) + b')'
     else:
         expr = None
     return expr
 
 
 def _initialrevs(repo, wopts):
     """Return the initial set of revisions to be filtered or followed"""
     if wopts.revspec:
         revs = scmutil.revrange(repo, wopts.revspec)
     elif wopts.follow and repo.dirstate.p1() == nullid:
         revs = smartset.baseset()
     elif wopts.follow:
         revs = repo.revs(b'.')
     else:
         revs = smartset.spanset(repo)
         revs.reverse()
     return revs
 
 
 def makewalker(repo, wopts):
     # type: (Any, walkopts) -> Tuple[smartset.abstractsmartset, Optional[Callable[[Any], matchmod.basematcher]]]
     """Build (revs, makefilematcher) to scan revision/file history
 
     - revs is the smartset to be traversed.
     - makefilematcher is a function to map ctx to a matcher for that revision
     """
     revs = _initialrevs(repo, wopts)
     if not revs:
         return smartset.baseset(), None
     # TODO: might want to merge slowpath with wopts.force_changelog_traversal
     match, pats, slowpath = _makematcher(repo, revs, wopts)
     wopts = attr.evolve(wopts, pats=pats)
 
     filematcher = None
     if wopts.follow:
         if slowpath or match.always():
             revs = dagop.revancestors(repo, revs, followfirst=wopts.follow == 1)
         else:
             assert not wopts.force_changelog_traversal
             revs, filematcher = _fileancestors(
                 repo, revs, match, followfirst=wopts.follow == 1
             )
         revs.reverse()
     if filematcher is None:
         filematcher = _makenofollowfilematcher(repo, wopts.pats, wopts.opts)
     if filematcher is None:
 
         def filematcher(ctx):
             return match
 
     expr = _makerevset(repo, wopts, slowpath)
     if wopts.sort_revisions:
         assert wopts.sort_revisions in {b'topo', b'desc'}
         if wopts.sort_revisions == b'topo':
             if not revs.istopo():
                 revs = dagop.toposort(revs, repo.changelog.parentrevs)
                 # TODO: try to iterate the set lazily
                 revs = revset.baseset(list(revs), istopo=True)
         elif not (revs.isdescending() or revs.istopo()):
             # User-specified revs might be unsorted
             revs.sort(reverse=True)
     if expr:
         matcher = revset.match(None, expr)
         revs = matcher(repo, revs)
     if wopts.limit is not None:
         revs = revs.slice(0, wopts.limit)
 
     return revs, filematcher
 
 
 def getrevs(repo, wopts):
     # type: (Any, walkopts) -> Tuple[smartset.abstractsmartset, Optional[changesetdiffer]]
     """Return (revs, differ) where revs is a smartset
 
     differ is a changesetdiffer with pre-configured file matcher.
     """
     revs, filematcher = makewalker(repo, wopts)
     if not revs:
         return revs, None
     differ = changesetdiffer()
     differ._makefilematcher = filematcher
     return revs, differ
 
 
 def _parselinerangeopt(repo, opts):
     """Parse --line-range log option and return a list of tuples (filename,
     (fromline, toline)).
     """
     linerangebyfname = []
     for pat in opts.get(b'line_range', []):
         try:
             pat, linerange = pat.rsplit(b',', 1)
         except ValueError:
             raise error.Abort(_(b'malformatted line-range pattern %s') % pat)
         try:
             fromline, toline = map(int, linerange.split(b':'))
         except ValueError:
             raise error.Abort(_(b"invalid line range for %s") % pat)
         msg = _(b"line range pattern '%s' must match exactly one file") % pat
         fname = scmutil.parsefollowlinespattern(repo, None, pat, msg)
         linerangebyfname.append(
             (fname, util.processlinerange(fromline, toline))
         )
     return linerangebyfname
 
 
 def getlinerangerevs(repo, userrevs, opts):
     """Return (revs, differ).
 
     "revs" are revisions obtained by processing "line-range" log options and
     walking block ancestors of each specified file/line-range.
 
     "differ" is a changesetdiffer with pre-configured file matcher and hunks
     filter.
     """
     wctx = repo[None]
 
     # Two-levels map of "rev -> file ctx -> [line range]".
     linerangesbyrev = {}
     for fname, (fromline, toline) in _parselinerangeopt(repo, opts):
         if fname not in wctx:
             raise error.Abort(
                 _(b'cannot follow file not in parent revision: "%s"') % fname
             )
         fctx = wctx.filectx(fname)
         for fctx, linerange in dagop.blockancestors(fctx, fromline, toline):
             rev = fctx.introrev()
             if rev is None:
                 rev = wdirrev
             if rev not in userrevs:
                 continue
             linerangesbyrev.setdefault(rev, {}).setdefault(
                 fctx.path(), []
             ).append(linerange)
 
     def nofilterhunksfn(fctx, hunks):
         return hunks
 
     def hunksfilter(ctx):
         fctxlineranges = linerangesbyrev.get(scmutil.intrev(ctx))
         if fctxlineranges is None:
             return nofilterhunksfn
 
         def filterfn(fctx, hunks):
             lineranges = fctxlineranges.get(fctx.path())
             if lineranges is not None:
                 for hr, lines in hunks:
                     if hr is None:  # binary
                         yield hr, lines
                         continue
                     if any(mdiff.hunkinrange(hr[2:], lr) for lr in lineranges):
                         yield hr, lines
             else:
                 for hunk in hunks:
                     yield hunk
 
         return filterfn
 
     def filematcher(ctx):
         files = list(linerangesbyrev.get(scmutil.intrev(ctx), []))
         return scmutil.matchfiles(repo, files)
 
     revs = sorted(linerangesbyrev, reverse=True)
 
     differ = changesetdiffer()
     differ._makefilematcher = filematcher
     differ._makehunksfilter = hunksfilter
     return smartset.baseset(revs), differ
 
 
 def _graphnodeformatter(ui, displayer):
     spec = ui.config(b'ui', b'graphnodetemplate')
     if not spec:
         return templatekw.getgraphnode  # fast path for "{graphnode}"
 
     spec = templater.unquotestring(spec)
     if isinstance(displayer, changesettemplater):
         # reuse cache of slow templates
         tres = displayer._tresources
     else:
         tres = formatter.templateresources(ui)
     templ = formatter.maketemplater(
         ui, spec, defaults=templatekw.keywords, resources=tres
     )
 
     def formatnode(repo, ctx, cache):
         props = {b'ctx': ctx, b'repo': repo}
         return templ.renderdefault(props)
 
     return formatnode
 
 
 def displaygraph(ui, repo, dag, displayer, edgefn, getcopies=None, props=None):
     props = props or {}
     formatnode = _graphnodeformatter(ui, displayer)
     state = graphmod.asciistate()
     styles = state.styles
 
     # only set graph styling if HGPLAIN is not set.
     if ui.plain(b'graph'):
         # set all edge styles to |, the default pre-3.8 behaviour
         styles.update(dict.fromkeys(styles, b'|'))
     else:
         edgetypes = {
             b'parent': graphmod.PARENT,
             b'grandparent': graphmod.GRANDPARENT,
             b'missing': graphmod.MISSINGPARENT,
         }
         for name, key in edgetypes.items():
             # experimental config: experimental.graphstyle.*
             styles[key] = ui.config(
                 b'experimental', b'graphstyle.%s' % name, styles[key]
             )
             if not styles[key]:
                 styles[key] = None
 
         # experimental config: experimental.graphshorten
         state.graphshorten = ui.configbool(b'experimental', b'graphshorten')
 
     formatnode_cache = {}
     for rev, type, ctx, parents in dag:
         char = formatnode(repo, ctx, formatnode_cache)
         copies = getcopies(ctx) if getcopies else None
         edges = edgefn(type, char, state, rev, parents)
         firstedge = next(edges)
         width = firstedge[2]
         displayer.show(
             ctx, copies=copies, graphwidth=width, **pycompat.strkwargs(props)
         )
         lines = displayer.hunk.pop(rev).split(b'\n')
         if not lines[-1]:
             del lines[-1]
         displayer.flush(ctx)
         for type, char, width, coldata in itertools.chain([firstedge], edges):
             graphmod.ascii(ui, state, type, char, lines, coldata)
             lines = []
     displayer.close()
 
 
 def displaygraphrevs(ui, repo, revs, displayer, getrenamed):
     revdag = graphmod.dagwalker(repo, revs)
     displaygraph(ui, repo, revdag, displayer, graphmod.asciiedges, getrenamed)
 
 
 def displayrevs(ui, repo, revs, displayer, getcopies):
     for rev in revs:
         ctx = repo[rev]
         copies = getcopies(ctx) if getcopies else None
         displayer.show(ctx, copies=copies)
         displayer.flush(ctx)
     displayer.close()
 
 
 def checkunsupportedgraphflags(pats, opts):
     for op in [b"newest_first"]:
         if op in opts and opts[op]:
             raise error.Abort(
                 _(b"-G/--graph option is incompatible with --%s")
                 % op.replace(b"_", b"-")
             )
 
 
 def graphrevs(repo, nodes, opts):
     limit = getlimit(opts)
     nodes.reverse()
     if limit is not None:
         nodes = nodes[:limit]
     return graphmod.nodes(repo, nodes)