upgrade: split actual upgrade code away from the main module

The main module is getting big and hard to follow. So we are splitting all the
logic to actually run an upgrade in a sub module. It nicely highlight that there
are very few actual call point to the code we just moved.

Differential Revision: https://phab.mercurial-scm.org/D9476

hgext/lfs/wrapper.py

@@ -1,546 +1,548 b''
 # wrapper.py - methods wrapping core mercurial logic
 #
 # Copyright 2017 Facebook, Inc.
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
 from __future__ import absolute_import
 
 import hashlib
 
 from mercurial.i18n import _
 from mercurial.node import bin, hex, nullid, short
 from mercurial.pycompat import (
     getattr,
     setattr,
 )
 
 from mercurial import (
     bundle2,
     changegroup,
     cmdutil,
     context,
     error,
     exchange,
     exthelper,
     localrepo,
     pycompat,
     revlog,
     scmutil,
     upgrade,
     util,
     vfs as vfsmod,
     wireprotov1server,
 )
 
+from mercurial.upgrade_utils import engine as upgrade_engine
+
 from mercurial.interfaces import repository
 
 from mercurial.utils import (
     storageutil,
     stringutil,
 )
 
 from ..largefiles import lfutil
 
 from . import (
     blobstore,
     pointer,
 )
 
 eh = exthelper.exthelper()
 
 
 @eh.wrapfunction(localrepo, b'makefilestorage')
 def localrepomakefilestorage(orig, requirements, features, **kwargs):
     if b'lfs' in requirements:
         features.add(repository.REPO_FEATURE_LFS)
 
     return orig(requirements=requirements, features=features, **kwargs)
 
 
 @eh.wrapfunction(changegroup, b'allsupportedversions')
 def allsupportedversions(orig, ui):
     versions = orig(ui)
     versions.add(b'03')
     return versions
 
 
 @eh.wrapfunction(wireprotov1server, b'_capabilities')
 def _capabilities(orig, repo, proto):
     '''Wrap server command to announce lfs server capability'''
     caps = orig(repo, proto)
     if util.safehasattr(repo.svfs, b'lfslocalblobstore'):
         # Advertise a slightly different capability when lfs is *required*, so
         # that the client knows it MUST load the extension.  If lfs is not
         # required on the server, there's no reason to autoload the extension
         # on the client.
         if b'lfs' in repo.requirements:
             caps.append(b'lfs-serve')
 
         caps.append(b'lfs')
     return caps
 
 
 def bypasscheckhash(self, text):
     return False
 
 
 def readfromstore(self, text):
     """Read filelog content from local blobstore transform for flagprocessor.
 
     Default tranform for flagprocessor, returning contents from blobstore.
     Returns a 2-typle (text, validatehash) where validatehash is True as the
     contents of the blobstore should be checked using checkhash.
     """
     p = pointer.deserialize(text)
     oid = p.oid()
     store = self.opener.lfslocalblobstore
     if not store.has(oid):
         p.filename = self.filename
         self.opener.lfsremoteblobstore.readbatch([p], store)
 
     # The caller will validate the content
     text = store.read(oid, verify=False)
 
     # pack hg filelog metadata
     hgmeta = {}
     for k in p.keys():
         if k.startswith(b'x-hg-'):
             name = k[len(b'x-hg-') :]
             hgmeta[name] = p[k]
     if hgmeta or text.startswith(b'\1\n'):
         text = storageutil.packmeta(hgmeta, text)
 
     return (text, True, {})
 
 
 def writetostore(self, text, sidedata):
     # hg filelog metadata (includes rename, etc)
     hgmeta, offset = storageutil.parsemeta(text)
     if offset and offset > 0:
         # lfs blob does not contain hg filelog metadata
         text = text[offset:]
 
     # git-lfs only supports sha256
     oid = hex(hashlib.sha256(text).digest())
     self.opener.lfslocalblobstore.write(oid, text)
 
     # replace contents with metadata
     longoid = b'sha256:%s' % oid
     metadata = pointer.gitlfspointer(oid=longoid, size=b'%d' % len(text))
 
     # by default, we expect the content to be binary. however, LFS could also
     # be used for non-binary content. add a special entry for non-binary data.
     # this will be used by filectx.isbinary().
     if not stringutil.binary(text):
         # not hg filelog metadata (affecting commit hash), no "x-hg-" prefix
         metadata[b'x-is-binary'] = b'0'
 
     # translate hg filelog metadata to lfs metadata with "x-hg-" prefix
     if hgmeta is not None:
         for k, v in pycompat.iteritems(hgmeta):
             metadata[b'x-hg-%s' % k] = v
 
     rawtext = metadata.serialize()
     return (rawtext, False)
 
 
 def _islfs(rlog, node=None, rev=None):
     if rev is None:
         if node is None:
             # both None - likely working copy content where node is not ready
             return False
         rev = rlog.rev(node)
     else:
         node = rlog.node(rev)
     if node == nullid:
         return False
     flags = rlog.flags(rev)
     return bool(flags & revlog.REVIDX_EXTSTORED)
 
 
 # Wrapping may also be applied by remotefilelog
 def filelogaddrevision(
     orig,
     self,
     text,
     transaction,
     link,
     p1,
     p2,
     cachedelta=None,
     node=None,
     flags=revlog.REVIDX_DEFAULT_FLAGS,
     **kwds
 ):
     # The matcher isn't available if reposetup() wasn't called.
     lfstrack = self._revlog.opener.options.get(b'lfstrack')
 
     if lfstrack:
         textlen = len(text)
         # exclude hg rename meta from file size
         meta, offset = storageutil.parsemeta(text)
         if offset:
             textlen -= offset
 
         if lfstrack(self._revlog.filename, textlen):
             flags |= revlog.REVIDX_EXTSTORED
 
     return orig(
         self,
         text,
         transaction,
         link,
         p1,
         p2,
         cachedelta=cachedelta,
         node=node,
         flags=flags,
         **kwds
     )
 
 
 # Wrapping may also be applied by remotefilelog
 def filelogrenamed(orig, self, node):
     if _islfs(self._revlog, node):
         rawtext = self._revlog.rawdata(node)
         if not rawtext:
             return False
         metadata = pointer.deserialize(rawtext)
         if b'x-hg-copy' in metadata and b'x-hg-copyrev' in metadata:
             return metadata[b'x-hg-copy'], bin(metadata[b'x-hg-copyrev'])
         else:
             return False
     return orig(self, node)
 
 
 # Wrapping may also be applied by remotefilelog
 def filelogsize(orig, self, rev):
     if _islfs(self._revlog, rev=rev):
         # fast path: use lfs metadata to answer size
         rawtext = self._revlog.rawdata(rev)
         metadata = pointer.deserialize(rawtext)
         return int(metadata[b'size'])
     return orig(self, rev)
 
 
 @eh.wrapfunction(revlog, b'_verify_revision')
 def _verify_revision(orig, rl, skipflags, state, node):
     if _islfs(rl, node=node):
         rawtext = rl.rawdata(node)
         metadata = pointer.deserialize(rawtext)
 
         # Don't skip blobs that are stored locally, as local verification is
         # relatively cheap and there's no other way to verify the raw data in
         # the revlog.
         if rl.opener.lfslocalblobstore.has(metadata.oid()):
             skipflags &= ~revlog.REVIDX_EXTSTORED
         elif skipflags & revlog.REVIDX_EXTSTORED:
             # The wrapped method will set `skipread`, but there's enough local
             # info to check renames.
             state[b'safe_renamed'].add(node)
 
     orig(rl, skipflags, state, node)
 
 
 @eh.wrapfunction(context.basefilectx, b'cmp')
 def filectxcmp(orig, self, fctx):
     """returns True if text is different than fctx"""
     # some fctx (ex. hg-git) is not based on basefilectx and do not have islfs
     if self.islfs() and getattr(fctx, 'islfs', lambda: False)():
         # fast path: check LFS oid
         p1 = pointer.deserialize(self.rawdata())
         p2 = pointer.deserialize(fctx.rawdata())
         return p1.oid() != p2.oid()
     return orig(self, fctx)
 
 
 @eh.wrapfunction(context.basefilectx, b'isbinary')
 def filectxisbinary(orig, self):
     if self.islfs():
         # fast path: use lfs metadata to answer isbinary
         metadata = pointer.deserialize(self.rawdata())
         # if lfs metadata says nothing, assume it's binary by default
         return bool(int(metadata.get(b'x-is-binary', 1)))
     return orig(self)
 
 
 def filectxislfs(self):
     return _islfs(self.filelog()._revlog, self.filenode())
 
 
 @eh.wrapfunction(cmdutil, b'_updatecatformatter')
 def _updatecatformatter(orig, fm, ctx, matcher, path, decode):
     orig(fm, ctx, matcher, path, decode)
     fm.data(rawdata=ctx[path].rawdata())
 
 
 @eh.wrapfunction(scmutil, b'wrapconvertsink')
 def convertsink(orig, sink):
     sink = orig(sink)
     if sink.repotype == b'hg':
 
         class lfssink(sink.__class__):
             def putcommit(
                 self,
                 files,
                 copies,
                 parents,
                 commit,
                 source,
                 revmap,
                 full,
                 cleanp2,
             ):
                 pc = super(lfssink, self).putcommit
                 node = pc(
                     files,
                     copies,
                     parents,
                     commit,
                     source,
                     revmap,
                     full,
                     cleanp2,
                 )
 
                 if b'lfs' not in self.repo.requirements:
                     ctx = self.repo[node]
 
                     # The file list may contain removed files, so check for
                     # membership before assuming it is in the context.
                     if any(f in ctx and ctx[f].islfs() for f, n in files):
                         self.repo.requirements.add(b'lfs')
                         scmutil.writereporequirements(self.repo)
 
                 return node
 
         sink.__class__ = lfssink
 
     return sink
 
 
 # bundlerepo uses "vfsmod.readonlyvfs(othervfs)", we need to make sure lfs
 # options and blob stores are passed from othervfs to the new readonlyvfs.
 @eh.wrapfunction(vfsmod.readonlyvfs, b'__init__')
 def vfsinit(orig, self, othervfs):
     orig(self, othervfs)
     # copy lfs related options
     for k, v in othervfs.options.items():
         if k.startswith(b'lfs'):
             self.options[k] = v
     # also copy lfs blobstores. note: this can run before reposetup, so lfs
     # blobstore attributes are not always ready at this time.
     for name in [b'lfslocalblobstore', b'lfsremoteblobstore']:
         if util.safehasattr(othervfs, name):
             setattr(self, name, getattr(othervfs, name))
 
 
 def _prefetchfiles(repo, revmatches):
     """Ensure that required LFS blobs are present, fetching them as a group if
     needed."""
     if not util.safehasattr(repo.svfs, b'lfslocalblobstore'):
         return
 
     pointers = []
     oids = set()
     localstore = repo.svfs.lfslocalblobstore
 
     for rev, match in revmatches:
         ctx = repo[rev]
         for f in ctx.walk(match):
             p = pointerfromctx(ctx, f)
             if p and p.oid() not in oids and not localstore.has(p.oid()):
                 p.filename = f
                 pointers.append(p)
                 oids.add(p.oid())
 
     if pointers:
         # Recalculating the repo store here allows 'paths.default' that is set
         # on the repo by a clone command to be used for the update.
         blobstore.remote(repo).readbatch(pointers, localstore)
 
 
 def _canskipupload(repo):
     # Skip if this hasn't been passed to reposetup()
     if not util.safehasattr(repo.svfs, b'lfsremoteblobstore'):
         return True
 
     # if remotestore is a null store, upload is a no-op and can be skipped
     return isinstance(repo.svfs.lfsremoteblobstore, blobstore._nullremote)
 
 
 def candownload(repo):
     # Skip if this hasn't been passed to reposetup()
     if not util.safehasattr(repo.svfs, b'lfsremoteblobstore'):
         return False
 
     # if remotestore is a null store, downloads will lead to nothing
     return not isinstance(repo.svfs.lfsremoteblobstore, blobstore._nullremote)
 
 
 def uploadblobsfromrevs(repo, revs):
     """upload lfs blobs introduced by revs
 
     Note: also used by other extensions e. g. infinitepush. avoid renaming.
     """
     if _canskipupload(repo):
         return
     pointers = extractpointers(repo, revs)
     uploadblobs(repo, pointers)
 
 
 def prepush(pushop):
     """Prepush hook.
 
     Read through the revisions to push, looking for filelog entries that can be
     deserialized into metadata so that we can block the push on their upload to
     the remote blobstore.
     """
     return uploadblobsfromrevs(pushop.repo, pushop.outgoing.missing)
 
 
 @eh.wrapfunction(exchange, b'push')
 def push(orig, repo, remote, *args, **kwargs):
     """bail on push if the extension isn't enabled on remote when needed, and
     update the remote store based on the destination path."""
     if b'lfs' in repo.requirements:
         # If the remote peer is for a local repo, the requirement tests in the
         # base class method enforce lfs support.  Otherwise, some revisions in
         # this repo use lfs, and the remote repo needs the extension loaded.
         if not remote.local() and not remote.capable(b'lfs'):
             # This is a copy of the message in exchange.push() when requirements
             # are missing between local repos.
             m = _(b"required features are not supported in the destination: %s")
             raise error.Abort(
                 m % b'lfs', hint=_(b'enable the lfs extension on the server')
             )
 
         # Repositories where this extension is disabled won't have the field.
         # But if there's a requirement, then the extension must be loaded AND
         # there may be blobs to push.
         remotestore = repo.svfs.lfsremoteblobstore
         try:
             repo.svfs.lfsremoteblobstore = blobstore.remote(repo, remote.url())
             return orig(repo, remote, *args, **kwargs)
         finally:
             repo.svfs.lfsremoteblobstore = remotestore
     else:
         return orig(repo, remote, *args, **kwargs)
 
 
 # when writing a bundle via "hg bundle" command, upload related LFS blobs
 @eh.wrapfunction(bundle2, b'writenewbundle')
 def writenewbundle(
     orig, ui, repo, source, filename, bundletype, outgoing, *args, **kwargs
 ):
     """upload LFS blobs added by outgoing revisions on 'hg bundle'"""
     uploadblobsfromrevs(repo, outgoing.missing)
     return orig(
         ui, repo, source, filename, bundletype, outgoing, *args, **kwargs
     )
 
 
 def extractpointers(repo, revs):
     """return a list of lfs pointers added by given revs"""
     repo.ui.debug(b'lfs: computing set of blobs to upload\n')
     pointers = {}
 
     makeprogress = repo.ui.makeprogress
     with makeprogress(
         _(b'lfs search'), _(b'changesets'), len(revs)
     ) as progress:
         for r in revs:
             ctx = repo[r]
             for p in pointersfromctx(ctx).values():
                 pointers[p.oid()] = p
             progress.increment()
         return sorted(pointers.values(), key=lambda p: p.oid())
 
 
 def pointerfromctx(ctx, f, removed=False):
     """return a pointer for the named file from the given changectx, or None if
     the file isn't LFS.
 
     Optionally, the pointer for a file deleted from the context can be returned.
     Since no such pointer is actually stored, and to distinguish from a non LFS
     file, this pointer is represented by an empty dict.
     """
     _ctx = ctx
     if f not in ctx:
         if not removed:
             return None
         if f in ctx.p1():
             _ctx = ctx.p1()
         elif f in ctx.p2():
             _ctx = ctx.p2()
         else:
             return None
     fctx = _ctx[f]
     if not _islfs(fctx.filelog()._revlog, fctx.filenode()):
         return None
     try:
         p = pointer.deserialize(fctx.rawdata())
         if ctx == _ctx:
             return p
         return {}
     except pointer.InvalidPointer as ex:
         raise error.Abort(
             _(b'lfs: corrupted pointer (%s@%s): %s\n')
             % (f, short(_ctx.node()), ex)
         )
 
 
 def pointersfromctx(ctx, removed=False):
     """return a dict {path: pointer} for given single changectx.
 
     If ``removed`` == True and the LFS file was removed from ``ctx``, the value
     stored for the path is an empty dict.
     """
     result = {}
     m = ctx.repo().narrowmatch()
 
     # TODO: consider manifest.fastread() instead
     for f in ctx.files():
         if not m(f):
             continue
         p = pointerfromctx(ctx, f, removed=removed)
         if p is not None:
             result[f] = p
     return result
 
 
 def uploadblobs(repo, pointers):
     """upload given pointers from local blobstore"""
     if not pointers:
         return
 
     remoteblob = repo.svfs.lfsremoteblobstore
     remoteblob.writebatch(pointers, repo.svfs.lfslocalblobstore)
 
 
[e-mail](upgrade, b'_finishdatamigration')
[e-mail](upgrade_engine, b'_finishdatamigration')
 def upgradefinishdatamigration(orig, ui, srcrepo, dstrepo, requirements):
     orig(ui, srcrepo, dstrepo, requirements)
 
     # Skip if this hasn't been passed to reposetup()
     if util.safehasattr(
         srcrepo.svfs, b'lfslocalblobstore'
     ) and util.safehasattr(dstrepo.svfs, b'lfslocalblobstore'):
         srclfsvfs = srcrepo.svfs.lfslocalblobstore.vfs
         dstlfsvfs = dstrepo.svfs.lfslocalblobstore.vfs
 
         for dirpath, dirs, files in srclfsvfs.walk():
             for oid in files:
                 ui.write(_(b'copying lfs blob %s\n') % oid)
                 lfutil.link(srclfsvfs.join(oid), dstlfsvfs.join(oid))
 
 
 @eh.wrapfunction(upgrade, b'preservedrequirements')
 @eh.wrapfunction(upgrade, b'supporteddestrequirements')
 def upgraderequirements(orig, repo):
     reqs = orig(repo)
     if b'lfs' in repo.requirements:
         reqs.add(b'lfs')
     return reqs

mercurial/upgrade.py

@@ -1,1492 +1,1012 b''
 # upgrade.py - functions for in place upgrade of Mercurial repository
 #
 # Copyright (c) 2016-present, Gregory Szorc
 #
 # 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 stat
-
 from .i18n import _
-from .pycompat import getattr
 from . import (
-    changelog,
     error,
-    filelog,
     hg,
     localrepo,
-    manifest,
-    metadata,
     pycompat,
     requirements,
-    revlog,
-    scmutil,
     util,
-    vfs as vfsmod,
+)
+
+from .upgrade_utils import (
+    engine as upgrade_engine,
 )
 
 from .utils import compression
 
 # list of requirements that request a clone of all revlog if added/removed
 RECLONES_REQUIREMENTS = {
     b'generaldelta',
     requirements.SPARSEREVLOG_REQUIREMENT,
 }
 
 
 def requiredsourcerequirements(repo):
     """Obtain requirements required to be present to upgrade a repo.
 
     An upgrade will not be allowed if the repository doesn't have the
     requirements returned by this function.
     """
     return {
         # Introduced in Mercurial 0.9.2.
         b'revlogv1',
         # Introduced in Mercurial 0.9.2.
         b'store',
     }
 
 
 def blocksourcerequirements(repo):
     """Obtain requirements that will prevent an upgrade from occurring.
 
     An upgrade cannot be performed if the source repository contains a
     requirements in the returned set.
     """
     return {
         # The upgrade code does not yet support these experimental features.
         # This is an artificial limitation.
         requirements.TREEMANIFEST_REQUIREMENT,
         # This was a precursor to generaldelta and was never enabled by default.
         # It should (hopefully) not exist in the wild.
         b'parentdelta',
         # Upgrade should operate on the actual store, not the shared link.
         requirements.SHARED_REQUIREMENT,
     }
 
 
 def supportremovedrequirements(repo):
     """Obtain requirements that can be removed during an upgrade.
 
     If an upgrade were to create a repository that dropped a requirement,
     the dropped requirement must appear in the returned set for the upgrade
     to be allowed.
     """
     supported = {
         requirements.SPARSEREVLOG_REQUIREMENT,
         requirements.SIDEDATA_REQUIREMENT,
         requirements.COPIESSDC_REQUIREMENT,
         requirements.NODEMAP_REQUIREMENT,
         requirements.SHARESAFE_REQUIREMENT,
     }
     for name in compression.compengines:
         engine = compression.compengines[name]
         if engine.available() and engine.revlogheader():
             supported.add(b'exp-compression-%s' % name)
             if engine.name() == b'zstd':
                 supported.add(b'revlog-compression-zstd')
     return supported
 
 
 def supporteddestrequirements(repo):
     """Obtain requirements that upgrade supports in the destination.
 
     If the result of the upgrade would create requirements not in this set,
     the upgrade is disallowed.
 
     Extensions should monkeypatch this to add their custom requirements.
     """
     supported = {
         b'dotencode',
         b'fncache',
         b'generaldelta',
         b'revlogv1',
         b'store',
         requirements.SPARSEREVLOG_REQUIREMENT,
         requirements.SIDEDATA_REQUIREMENT,
         requirements.COPIESSDC_REQUIREMENT,
         requirements.NODEMAP_REQUIREMENT,
         requirements.SHARESAFE_REQUIREMENT,
     }
     for name in compression.compengines:
         engine = compression.compengines[name]
         if engine.available() and engine.revlogheader():
             supported.add(b'exp-compression-%s' % name)
             if engine.name() == b'zstd':
                 supported.add(b'revlog-compression-zstd')
     return supported
 
 
 def allowednewrequirements(repo):
     """Obtain requirements that can be added to a repository during upgrade.
 
     This is used to disallow proposed requirements from being added when
     they weren't present before.
 
     We use a list of allowed requirement additions instead of a list of known
     bad additions because the whitelist approach is safer and will prevent
     future, unknown requirements from accidentally being added.
     """
     supported = {
         b'dotencode',
         b'fncache',
         b'generaldelta',
         requirements.SPARSEREVLOG_REQUIREMENT,
         requirements.SIDEDATA_REQUIREMENT,
         requirements.COPIESSDC_REQUIREMENT,
         requirements.NODEMAP_REQUIREMENT,
         requirements.SHARESAFE_REQUIREMENT,
     }
     for name in compression.compengines:
         engine = compression.compengines[name]
         if engine.available() and engine.revlogheader():
             supported.add(b'exp-compression-%s' % name)
             if engine.name() == b'zstd':
                 supported.add(b'revlog-compression-zstd')
     return supported
 
 
 def preservedrequirements(repo):
     return set()
 
 
 DEFICIENCY = b'deficiency'
 OPTIMISATION = b'optimization'
 
 
 class improvement(object):
     """Represents an improvement that can be made as part of an upgrade.
 
     The following attributes are defined on each instance:
 
     name
        Machine-readable string uniquely identifying this improvement. It
        will be mapped to an action later in the upgrade process.
 
     type
        Either ``DEFICIENCY`` or ``OPTIMISATION``. A deficiency is an obvious
        problem. An optimization is an action (sometimes optional) that
        can be taken to further improve the state of the repository.
 
     description
        Message intended for humans explaining the improvement in more detail,
        including the implications of it. For ``DEFICIENCY`` types, should be
        worded in the present tense. For ``OPTIMISATION`` types, should be
        worded in the future tense.
 
     upgrademessage
        Message intended for humans explaining what an upgrade addressing this
        issue will do. Should be worded in the future tense.
     """
 
     def __init__(self, name, type, description, upgrademessage):
         self.name = name
         self.type = type
         self.description = description
         self.upgrademessage = upgrademessage
 
     def __eq__(self, other):
         if not isinstance(other, improvement):
             # This is what python tell use to do
             return NotImplemented
         return self.name == other.name
 
     def __ne__(self, other):
         return not (self == other)
 
     def __hash__(self):
         return hash(self.name)
 
 
 allformatvariant = []
 
 
 def registerformatvariant(cls):
     allformatvariant.append(cls)
     return cls
 
 
 class formatvariant(improvement):
     """an improvement subclass dedicated to repository format"""
 
     type = DEFICIENCY
     ### The following attributes should be defined for each class:
 
     # machine-readable string uniquely identifying this improvement. it will be
     # mapped to an action later in the upgrade process.
     name = None
 
     # message intended for humans explaining the improvement in more detail,
     # including the implications of it ``DEFICIENCY`` types, should be worded
     # in the present tense.
     description = None
 
     # message intended for humans explaining what an upgrade addressing this
     # issue will do. should be worded in the future tense.
     upgrademessage = None
 
     # value of current Mercurial default for new repository
     default = None
 
     def __init__(self):
         raise NotImplementedError()
 
     @staticmethod
     def fromrepo(repo):
         """current value of the variant in the repository"""
         raise NotImplementedError()
 
     @staticmethod
     def fromconfig(repo):
         """current value of the variant in the configuration"""
         raise NotImplementedError()
 
 
 class requirementformatvariant(formatvariant):
     """formatvariant based on a 'requirement' name.
 
     Many format variant are controlled by a 'requirement'. We define a small
     subclass to factor the code.
     """
 
     # the requirement that control this format variant
     _requirement = None
 
     @staticmethod
     def _newreporequirements(ui):
         return localrepo.newreporequirements(
             ui, localrepo.defaultcreateopts(ui)
         )
 
     @classmethod
     def fromrepo(cls, repo):
         assert cls._requirement is not None
         return cls._requirement in repo.requirements
 
     @classmethod
     def fromconfig(cls, repo):
         assert cls._requirement is not None
         return cls._requirement in cls._newreporequirements(repo.ui)
 
 
 @registerformatvariant
 class fncache(requirementformatvariant):
     name = b'fncache'
 
     _requirement = b'fncache'
 
     default = True
 
     description = _(
         b'long and reserved filenames may not work correctly; '
         b'repository performance is sub-optimal'
     )
 
     upgrademessage = _(
         b'repository will be more resilient to storing '
         b'certain paths and performance of certain '
         b'operations should be improved'
     )
 
 
 @registerformatvariant
 class dotencode(requirementformatvariant):
     name = b'dotencode'
 
     _requirement = b'dotencode'
 
     default = True
 
     description = _(
         b'storage of filenames beginning with a period or '
         b'space may not work correctly'
     )
 
     upgrademessage = _(
         b'repository will be better able to store files '
         b'beginning with a space or period'
     )
 
 
 @registerformatvariant
 class generaldelta(requirementformatvariant):
     name = b'generaldelta'
 
     _requirement = b'generaldelta'
 
     default = True
 
     description = _(
         b'deltas within internal storage are unable to '
         b'choose optimal revisions; repository is larger and '
         b'slower than it could be; interaction with other '
         b'repositories may require extra network and CPU '
         b'resources, making "hg push" and "hg pull" slower'
     )
 
     upgrademessage = _(
         b'repository storage will be able to create '
         b'optimal deltas; new repository data will be '
         b'smaller and read times should decrease; '
         b'interacting with other repositories using this '
         b'storage model should require less network and '
         b'CPU resources, making "hg push" and "hg pull" '
         b'faster'
     )
 
 
 @registerformatvariant
 class sharedsafe(requirementformatvariant):
     name = b'exp-sharesafe'
     _requirement = requirements.SHARESAFE_REQUIREMENT
 
     default = False
 
     description = _(
         b'old shared repositories do not share source repository '
         b'requirements and config. This leads to various problems '
         b'when the source repository format is upgraded or some new '
         b'extensions are enabled.'
     )
 
     upgrademessage = _(
         b'Upgrades a repository to share-safe format so that future '
         b'shares of this repository share its requirements and configs.'
     )
 
 
 @registerformatvariant
 class sparserevlog(requirementformatvariant):
     name = b'sparserevlog'
 
     _requirement = requirements.SPARSEREVLOG_REQUIREMENT
 
     default = True
 
     description = _(
         b'in order to limit disk reading and memory usage on older '
         b'version, the span of a delta chain from its root to its '
         b'end is limited, whatever the relevant data in this span. '
         b'This can severly limit Mercurial ability to build good '
         b'chain of delta resulting is much more storage space being '
         b'taken and limit reusability of on disk delta during '
         b'exchange.'
     )
 
     upgrademessage = _(
         b'Revlog supports delta chain with more unused data '
         b'between payload. These gaps will be skipped at read '
         b'time. This allows for better delta chains, making a '
         b'better compression and faster exchange with server.'
     )
 
 
 @registerformatvariant
 class sidedata(requirementformatvariant):
     name = b'sidedata'
 
     _requirement = requirements.SIDEDATA_REQUIREMENT
 
     default = False
 
     description = _(
         b'Allows storage of extra data alongside a revision, '
         b'unlocking various caching options.'
     )
 
     upgrademessage = _(b'Allows storage of extra data alongside a revision.')
 
 
 @registerformatvariant
 class persistentnodemap(requirementformatvariant):
     name = b'persistent-nodemap'
 
     _requirement = requirements.NODEMAP_REQUIREMENT
 
     default = False
 
     description = _(
         b'persist the node -> rev mapping on disk to speedup lookup'
     )
 
     upgrademessage = _(b'Speedup revision lookup by node id.')
 
 
 @registerformatvariant
 class copiessdc(requirementformatvariant):
     name = b'copies-sdc'
 
     _requirement = requirements.COPIESSDC_REQUIREMENT
 
     default = False
 
     description = _(b'Stores copies information alongside changesets.')
 
     upgrademessage = _(
         b'Allows to use more efficient algorithm to deal with ' b'copy tracing.'
     )
 
 
 @registerformatvariant
 class removecldeltachain(formatvariant):
     name = b'plain-cl-delta'
 
     default = True
 
     description = _(
         b'changelog storage is using deltas instead of '
         b'raw entries; changelog reading and any '
         b'operation relying on changelog data are slower '
         b'than they could be'
     )
 
     upgrademessage = _(
         b'changelog storage will be reformated to '
         b'store raw entries; changelog reading will be '
         b'faster; changelog size may be reduced'
     )
 
     @staticmethod
     def fromrepo(repo):
         # Mercurial 4.0 changed changelogs to not use delta chains. Search for
         # changelogs with deltas.
         cl = repo.changelog
         chainbase = cl.chainbase
         return all(rev == chainbase(rev) for rev in cl)
 
     @staticmethod
     def fromconfig(repo):
         return True
 
 
 @registerformatvariant
 class compressionengine(formatvariant):
     name = b'compression'
     default = b'zlib'
 
     description = _(
         b'Compresion algorithm used to compress data. '
         b'Some engine are faster than other'
     )
 
     upgrademessage = _(
         b'revlog content will be recompressed with the new algorithm.'
     )
 
     @classmethod
     def fromrepo(cls, repo):
         # we allow multiple compression engine requirement to co-exist because
         # strickly speaking, revlog seems to support mixed compression style.
         #
         # The compression used for new entries will be "the last one"
         compression = b'zlib'
         for req in repo.requirements:
             prefix = req.startswith
             if prefix(b'revlog-compression-') or prefix(b'exp-compression-'):
                 compression = req.split(b'-', 2)[2]
         return compression
 
     @classmethod
     def fromconfig(cls, repo):
         compengines = repo.ui.configlist(b'format', b'revlog-compression')
         # return the first valid value as the selection code would do
         for comp in compengines:
             if comp in util.compengines:
                 return comp
 
         # no valide compression found lets display it all for clarity
         return b','.join(compengines)
 
 
 @registerformatvariant
 class compressionlevel(formatvariant):
     name = b'compression-level'
     default = b'default'
 
     description = _(b'compression level')
 
     upgrademessage = _(b'revlog content will be recompressed')
 
     @classmethod
     def fromrepo(cls, repo):
         comp = compressionengine.fromrepo(repo)
         level = None
         if comp == b'zlib':
             level = repo.ui.configint(b'storage', b'revlog.zlib.level')
         elif comp == b'zstd':
             level = repo.ui.configint(b'storage', b'revlog.zstd.level')
         if level is None:
             return b'default'
         return bytes(level)
 
     @classmethod
     def fromconfig(cls, repo):
         comp = compressionengine.fromconfig(repo)
         level = None
         if comp == b'zlib':
             level = repo.ui.configint(b'storage', b'revlog.zlib.level')
         elif comp == b'zstd':
             level = repo.ui.configint(b'storage', b'revlog.zstd.level')
         if level is None:
             return b'default'
         return bytes(level)
 
 
 def finddeficiencies(repo):
     """returns a list of deficiencies that the repo suffer from"""
     deficiencies = []
 
     # We could detect lack of revlogv1 and store here, but they were added
     # in 0.9.2 and we don't support upgrading repos without these
     # requirements, so let's not bother.
 
     for fv in allformatvariant:
         if not fv.fromrepo(repo):
             deficiencies.append(fv)
 
     return deficiencies
 
 
 # search without '-' to support older form on newer client.
 #
 # We don't enforce backward compatibility for debug command so this
 # might eventually be dropped. However, having to use two different
 # forms in script when comparing result is anoying enough to add
 # backward compatibility for a while.
 legacy_opts_map = {
     b'redeltaparent': b're-delta-parent',
     b'redeltamultibase': b're-delta-multibase',
     b'redeltaall': b're-delta-all',
     b'redeltafulladd': b're-delta-fulladd',
 }
 
 ALL_OPTIMISATIONS = []
 
 
 def register_optimization(obj):
     ALL_OPTIMISATIONS.append(obj)
     return obj
 
 
 register_optimization(
     improvement(
         name=b're-delta-parent',
         type=OPTIMISATION,
         description=_(
             b'deltas within internal storage will be recalculated to '
             b'choose an optimal base revision where this was not '
             b'already done; the size of the repository may shrink and '
             b'various operations may become faster; the first time '
             b'this optimization is performed could slow down upgrade '
             b'execution considerably; subsequent invocations should '
             b'not run noticeably slower'
         ),
         upgrademessage=_(
             b'deltas within internal storage will choose a new '
             b'base revision if needed'
         ),
     )
 )
 
 register_optimization(
     improvement(
         name=b're-delta-multibase',
         type=OPTIMISATION,
         description=_(
             b'deltas within internal storage will be recalculated '
             b'against multiple base revision and the smallest '
             b'difference will be used; the size of the repository may '
             b'shrink significantly when there are many merges; this '
             b'optimization will slow down execution in proportion to '
             b'the number of merges in the repository and the amount '
             b'of files in the repository; this slow down should not '
             b'be significant unless there are tens of thousands of '
             b'files and thousands of merges'
         ),
         upgrademessage=_(
             b'deltas within internal storage will choose an '
             b'optimal delta by computing deltas against multiple '
             b'parents; may slow down execution time '
             b'significantly'
         ),
     )
 )
 
 register_optimization(
     improvement(
         name=b're-delta-all',
         type=OPTIMISATION,
         description=_(
             b'deltas within internal storage will always be '
             b'recalculated without reusing prior deltas; this will '
             b'likely make execution run several times slower; this '
             b'optimization is typically not needed'
         ),
         upgrademessage=_(
             b'deltas within internal storage will be fully '
             b'recomputed; this will likely drastically slow down '
             b'execution time'
         ),
     )
 )
 
 register_optimization(
     improvement(
         name=b're-delta-fulladd',
         type=OPTIMISATION,
         description=_(
             b'every revision will be re-added as if it was new '
             b'content. It will go through the full storage '
             b'mechanism giving extensions a chance to process it '
             b'(eg. lfs). This is similar to "re-delta-all" but even '
             b'slower since more logic is involved.'
         ),
         upgrademessage=_(
             b'each revision will be added as new content to the '
             b'internal storage; this will likely drastically slow '
             b'down execution time, but some extensions might need '
             b'it'
         ),
     )
 )
 
 
 def findoptimizations(repo):
     """Determine optimisation that could be used during upgrade"""
     # These are unconditionally added. There is logic later that figures out
     # which ones to apply.
     return list(ALL_OPTIMISATIONS)
 
 
 def determineactions(repo, deficiencies, sourcereqs, destreqs):
     """Determine upgrade actions that will be performed.
 
     Given a list of improvements as returned by ``finddeficiencies`` and
     ``findoptimizations``, determine the list of upgrade actions that
     will be performed.
 
     The role of this function is to filter improvements if needed, apply
     recommended optimizations from the improvements list that make sense,
     etc.
 
     Returns a list of action names.
     """
     newactions = []
 
     for d in deficiencies:
         name = d._requirement
 
         # If the action is a requirement that doesn't show up in the
         # destination requirements, prune the action.
         if name is not None and name not in destreqs:
             continue
 
         newactions.append(d)
 
     # FUTURE consider adding some optimizations here for certain transitions.
     # e.g. adding generaldelta could schedule parent redeltas.
 
     return newactions
 
 
-def _revlogfrompath(repo, path):
-    """Obtain a revlog from a repo path.
-
-    An instance of the appropriate class is returned.
-    """
-    if path == b'00changelog.i':
-        return changelog.changelog(repo.svfs)
-    elif path.endswith(b'00manifest.i'):
-        mandir = path[: -len(b'00manifest.i')]
-        return manifest.manifestrevlog(repo.svfs, tree=mandir)
-    else:
-        # reverse of "/".join(("data", path + ".i"))
-        return filelog.filelog(repo.svfs, path[5:-2])
-
-
-def _copyrevlog(tr, destrepo, oldrl, unencodedname):
-    """copy all relevant files for `oldrl` into `destrepo` store
-
-    Files are copied "as is" without any transformation. The copy is performed
-    without extra checks. Callers are responsible for making sure the copied
-    content is compatible with format of the destination repository.
-    """
-    oldrl = getattr(oldrl, '_revlog', oldrl)
-    newrl = _revlogfrompath(destrepo, unencodedname)
-    newrl = getattr(newrl, '_revlog', newrl)
-
-    oldvfs = oldrl.opener
-    newvfs = newrl.opener
-    oldindex = oldvfs.join(oldrl.indexfile)
-    newindex = newvfs.join(newrl.indexfile)
-    olddata = oldvfs.join(oldrl.datafile)
-    newdata = newvfs.join(newrl.datafile)
-
-    with newvfs(newrl.indexfile, b'w'):
-        pass  # create all the directories
-
-    util.copyfile(oldindex, newindex)
-    copydata = oldrl.opener.exists(oldrl.datafile)
-    if copydata:
-        util.copyfile(olddata, newdata)
-
-    if not (
-        unencodedname.endswith(b'00changelog.i')
-        or unencodedname.endswith(b'00manifest.i')
-    ):
-        destrepo.svfs.fncache.add(unencodedname)
-        if copydata:
-            destrepo.svfs.fncache.add(unencodedname[:-2] + b'.d')
-
-
-UPGRADE_CHANGELOG = b"changelog"
-UPGRADE_MANIFEST = b"manifest"
-UPGRADE_FILELOGS = b"all-filelogs"
-
-UPGRADE_ALL_REVLOGS = frozenset(
-    [UPGRADE_CHANGELOG, UPGRADE_MANIFEST, UPGRADE_FILELOGS]
-)
-
-
-def getsidedatacompanion(srcrepo, dstrepo):
-    sidedatacompanion = None
-    removedreqs = srcrepo.requirements - dstrepo.requirements
-    addedreqs = dstrepo.requirements - srcrepo.requirements
-    if requirements.SIDEDATA_REQUIREMENT in removedreqs:
-
-        def sidedatacompanion(rl, rev):
-            rl = getattr(rl, '_revlog', rl)
-            if rl.flags(rev) & revlog.REVIDX_SIDEDATA:
-                return True, (), {}, 0, 0
-            return False, (), {}, 0, 0
-
-    elif requirements.COPIESSDC_REQUIREMENT in addedreqs:
-        sidedatacompanion = metadata.getsidedataadder(srcrepo, dstrepo)
-    elif requirements.COPIESSDC_REQUIREMENT in removedreqs:
-        sidedatacompanion = metadata.getsidedataremover(srcrepo, dstrepo)
-    return sidedatacompanion
-
-
-def matchrevlog(revlogfilter, entry):
-    """check if a revlog is selected for cloning.
-
-    In other words, are there any updates which need to be done on revlog
-    or it can be blindly copied.
-
-    The store entry is checked against the passed filter"""
-    if entry.endswith(b'00changelog.i'):
-        return UPGRADE_CHANGELOG in revlogfilter
-    elif entry.endswith(b'00manifest.i'):
-        return UPGRADE_MANIFEST in revlogfilter
-    return UPGRADE_FILELOGS in revlogfilter
-
-
-def _clonerevlogs(
-    ui,
-    srcrepo,
-    dstrepo,
-    tr,
-    deltareuse,
-    forcedeltabothparents,
-    revlogs=UPGRADE_ALL_REVLOGS,
-):
-    """Copy revlogs between 2 repos."""
-    revcount = 0
-    srcsize = 0
-    srcrawsize = 0
-    dstsize = 0
-    fcount = 0
-    frevcount = 0
-    fsrcsize = 0
-    frawsize = 0
-    fdstsize = 0
-    mcount = 0
-    mrevcount = 0
-    msrcsize = 0
-    mrawsize = 0
-    mdstsize = 0
-    crevcount = 0
-    csrcsize = 0
-    crawsize = 0
-    cdstsize = 0
-
-    alldatafiles = list(srcrepo.store.walk())
-
-    # Perform a pass to collect metadata. This validates we can open all
-    # source files and allows a unified progress bar to be displayed.
-    for unencoded, encoded, size in alldatafiles:
-        if unencoded.endswith(b'.d'):
-            continue
-
-        rl = _revlogfrompath(srcrepo, unencoded)
-
-        info = rl.storageinfo(
-            exclusivefiles=True,
-            revisionscount=True,
-            trackedsize=True,
-            storedsize=True,
-        )
-
-        revcount += info[b'revisionscount'] or 0
-        datasize = info[b'storedsize'] or 0
-        rawsize = info[b'trackedsize'] or 0
-
-        srcsize += datasize
-        srcrawsize += rawsize
-
-        # This is for the separate progress bars.
-        if isinstance(rl, changelog.changelog):
-            crevcount += len(rl)
-            csrcsize += datasize
-            crawsize += rawsize
-        elif isinstance(rl, manifest.manifestrevlog):
-            mcount += 1
-            mrevcount += len(rl)
-            msrcsize += datasize
-            mrawsize += rawsize
-        elif isinstance(rl, filelog.filelog):
-            fcount += 1
-            frevcount += len(rl)
-            fsrcsize += datasize
-            frawsize += rawsize
-        else:
-            error.ProgrammingError(b'unknown revlog type')
-
-    if not revcount:
-        return
-
-    ui.status(
-        _(
-            b'migrating %d total revisions (%d in filelogs, %d in manifests, '
-            b'%d in changelog)\n'
-        )
-        % (revcount, frevcount, mrevcount, crevcount)
-    )
-    ui.status(
-        _(b'migrating %s in store; %s tracked data\n')
-        % ((util.bytecount(srcsize), util.bytecount(srcrawsize)))
-    )
-
-    # Used to keep track of progress.
-    progress = None
-
-    def oncopiedrevision(rl, rev, node):
-        progress.increment()
-
-    sidedatacompanion = getsidedatacompanion(srcrepo, dstrepo)
-
-    # Do the actual copying.
-    # FUTURE this operation can be farmed off to worker processes.
-    seen = set()
-    for unencoded, encoded, size in alldatafiles:
-        if unencoded.endswith(b'.d'):
-            continue
-
-        oldrl = _revlogfrompath(srcrepo, unencoded)
-
-        if isinstance(oldrl, changelog.changelog) and b'c' not in seen:
-            ui.status(
-                _(
-                    b'finished migrating %d manifest revisions across %d '
-                    b'manifests; change in size: %s\n'
-                )
-                % (mrevcount, mcount, util.bytecount(mdstsize - msrcsize))
-            )
-
-            ui.status(
-                _(
-                    b'migrating changelog containing %d revisions '
-                    b'(%s in store; %s tracked data)\n'
-                )
-                % (
-                    crevcount,
-                    util.bytecount(csrcsize),
-                    util.bytecount(crawsize),
-                )
-            )
-            seen.add(b'c')
-            progress = srcrepo.ui.makeprogress(
-                _(b'changelog revisions'), total=crevcount
-            )
-        elif isinstance(oldrl, manifest.manifestrevlog) and b'm' not in seen:
-            ui.status(
-                _(
-                    b'finished migrating %d filelog revisions across %d '
-                    b'filelogs; change in size: %s\n'
-                )
-                % (frevcount, fcount, util.bytecount(fdstsize - fsrcsize))
-            )
-
-            ui.status(
-                _(
-                    b'migrating %d manifests containing %d revisions '
-                    b'(%s in store; %s tracked data)\n'
-                )
-                % (
-                    mcount,
-                    mrevcount,
-                    util.bytecount(msrcsize),
-                    util.bytecount(mrawsize),
-                )
-            )
-            seen.add(b'm')
-            if progress:
-                progress.complete()
-            progress = srcrepo.ui.makeprogress(
-                _(b'manifest revisions'), total=mrevcount
-            )
-        elif b'f' not in seen:
-            ui.status(
-                _(
-                    b'migrating %d filelogs containing %d revisions '
-                    b'(%s in store; %s tracked data)\n'
-                )
-                % (
-                    fcount,
-                    frevcount,
-                    util.bytecount(fsrcsize),
-                    util.bytecount(frawsize),
-                )
-            )
-            seen.add(b'f')
-            if progress:
-                progress.complete()
-            progress = srcrepo.ui.makeprogress(
-                _(b'file revisions'), total=frevcount
-            )
-
-        if matchrevlog(revlogs, unencoded):
-            ui.note(
-                _(b'cloning %d revisions from %s\n') % (len(oldrl), unencoded)
-            )
-            newrl = _revlogfrompath(dstrepo, unencoded)
-            oldrl.clone(
-                tr,
-                newrl,
-                addrevisioncb=oncopiedrevision,
-                deltareuse=deltareuse,
-                forcedeltabothparents=forcedeltabothparents,
-                sidedatacompanion=sidedatacompanion,
-            )
-        else:
-            msg = _(b'blindly copying %s containing %i revisions\n')
-            ui.note(msg % (unencoded, len(oldrl)))
-            _copyrevlog(tr, dstrepo, oldrl, unencoded)
-
-            newrl = _revlogfrompath(dstrepo, unencoded)
-
-        info = newrl.storageinfo(storedsize=True)
-        datasize = info[b'storedsize'] or 0
-
-        dstsize += datasize
-
-        if isinstance(newrl, changelog.changelog):
-            cdstsize += datasize
-        elif isinstance(newrl, manifest.manifestrevlog):
-            mdstsize += datasize
-        else:
-            fdstsize += datasize
-
-    progress.complete()
-
-    ui.status(
-        _(
-            b'finished migrating %d changelog revisions; change in size: '
-            b'%s\n'
-        )
-        % (crevcount, util.bytecount(cdstsize - csrcsize))
-    )
-
-    ui.status(
-        _(
-            b'finished migrating %d total revisions; total change in store '
-            b'size: %s\n'
-        )
-        % (revcount, util.bytecount(dstsize - srcsize))
-    )
-
-
-def _filterstorefile(srcrepo, dstrepo, requirements, path, mode, st):
-    """Determine whether to copy a store file during upgrade.
-
-    This function is called when migrating store files from ``srcrepo`` to
-    ``dstrepo`` as part of upgrading a repository.
-
-    Args:
-      srcrepo: repo we are copying from
-      dstrepo: repo we are copying to
-      requirements: set of requirements for ``dstrepo``
-      path: store file being examined
-      mode: the ``ST_MODE`` file type of ``path``
-      st: ``stat`` data structure for ``path``
-
-    Function should return ``True`` if the file is to be copied.
-    """
-    # Skip revlogs.
-    if path.endswith((b'.i', b'.d', b'.n', b'.nd')):
-        return False
-    # Skip transaction related files.
-    if path.startswith(b'undo'):
-        return False
-    # Only copy regular files.
-    if mode != stat.S_IFREG:
-        return False
-    # Skip other skipped files.
-    if path in (b'lock', b'fncache'):
-        return False
-
-    return True
-
-
-def _finishdatamigration(ui, srcrepo, dstrepo, requirements):
-    """Hook point for extensions to perform additional actions during upgrade.
-
-    This function is called after revlogs and store files have been copied but
-    before the new store is swapped into the original location.
-    """
-
-
-def _upgraderepo(
-    ui, srcrepo, dstrepo, requirements, actions, revlogs=UPGRADE_ALL_REVLOGS
-):
-    """Do the low-level work of upgrading a repository.
-
-    The upgrade is effectively performed as a copy between a source
-    repository and a temporary destination repository.
-
-    The source repository is unmodified for as long as possible so the
-    upgrade can abort at any time without causing loss of service for
-    readers and without corrupting the source repository.
-    """
-    assert srcrepo.currentwlock()
-    assert dstrepo.currentwlock()
-
-    ui.status(
-        _(
-            b'(it is safe to interrupt this process any time before '
-            b'data migration completes)\n'
-        )
-    )
-
-    if b're-delta-all' in actions:
-        deltareuse = revlog.revlog.DELTAREUSENEVER
-    elif b're-delta-parent' in actions:
-        deltareuse = revlog.revlog.DELTAREUSESAMEREVS
-    elif b're-delta-multibase' in actions:
-        deltareuse = revlog.revlog.DELTAREUSESAMEREVS
-    elif b're-delta-fulladd' in actions:
-        deltareuse = revlog.revlog.DELTAREUSEFULLADD
-    else:
-        deltareuse = revlog.revlog.DELTAREUSEALWAYS
-
-    with dstrepo.transaction(b'upgrade') as tr:
-        _clonerevlogs(
-            ui,
-            srcrepo,
-            dstrepo,
-            tr,
-            deltareuse,
-            b're-delta-multibase' in actions,
-            revlogs=revlogs,
-        )
-
-    # Now copy other files in the store directory.
-    # The sorted() makes execution deterministic.
-    for p, kind, st in sorted(srcrepo.store.vfs.readdir(b'', stat=True)):
-        if not _filterstorefile(srcrepo, dstrepo, requirements, p, kind, st):
-            continue
-
-        srcrepo.ui.status(_(b'copying %s\n') % p)
-        src = srcrepo.store.rawvfs.join(p)
-        dst = dstrepo.store.rawvfs.join(p)
-        util.copyfile(src, dst, copystat=True)
-
-    _finishdatamigration(ui, srcrepo, dstrepo, requirements)
-
-    ui.status(_(b'data fully migrated to temporary repository\n'))
-
-    backuppath = pycompat.mkdtemp(prefix=b'upgradebackup.', dir=srcrepo.path)
-    backupvfs = vfsmod.vfs(backuppath)
-
-    # Make a backup of requires file first, as it is the first to be modified.
-    util.copyfile(srcrepo.vfs.join(b'requires'), backupvfs.join(b'requires'))
-
-    # We install an arbitrary requirement that clients must not support
-    # as a mechanism to lock out new clients during the data swap. This is
-    # better than allowing a client to continue while the repository is in
-    # an inconsistent state.
-    ui.status(
-        _(
-            b'marking source repository as being upgraded; clients will be '
-            b'unable to read from repository\n'
-        )
-    )
-    scmutil.writereporequirements(
-        srcrepo, srcrepo.requirements | {b'upgradeinprogress'}
-    )
-
-    ui.status(_(b'starting in-place swap of repository data\n'))
-    ui.status(_(b'replaced files will be backed up at %s\n') % backuppath)
-
-    # Now swap in the new store directory. Doing it as a rename should make
-    # the operation nearly instantaneous and atomic (at least in well-behaved
-    # environments).
-    ui.status(_(b'replacing store...\n'))
-    tstart = util.timer()
-    util.rename(srcrepo.spath, backupvfs.join(b'store'))
-    util.rename(dstrepo.spath, srcrepo.spath)
-    elapsed = util.timer() - tstart
-    ui.status(
-        _(
-            b'store replacement complete; repository was inconsistent for '
-            b'%0.1fs\n'
-        )
-        % elapsed
-    )
-
-    # We first write the requirements file. Any new requirements will lock
-    # out legacy clients.
-    ui.status(
-        _(
-            b'finalizing requirements file and making repository readable '
-            b'again\n'
-        )
-    )
-    scmutil.writereporequirements(srcrepo, requirements)
-
-    # The lock file from the old store won't be removed because nothing has a
-    # reference to its new location. So clean it up manually. Alternatively, we
-    # could update srcrepo.svfs and other variables to point to the new
-    # location. This is simpler.
-    backupvfs.unlink(b'store/lock')
-
-    return backuppath
-
-
 def upgraderepo(
     ui,
     repo,
     run=False,
     optimize=None,
     backup=True,
     manifest=None,
     changelog=None,
     filelogs=None,
 ):
     """Upgrade a repository in place."""
     if optimize is None:
         optimize = []
     optimize = {legacy_opts_map.get(o, o) for o in optimize}
     repo = repo.unfiltered()
 
-    revlogs = set(UPGRADE_ALL_REVLOGS)
+    revlogs = set(upgrade_engine.UPGRADE_ALL_REVLOGS)
     specentries = (
-        (UPGRADE_CHANGELOG, changelog),
-        (UPGRADE_MANIFEST, manifest),
-        (UPGRADE_FILELOGS, filelogs),
+        (upgrade_engine.UPGRADE_CHANGELOG, changelog),
+        (upgrade_engine.UPGRADE_MANIFEST, manifest),
+        (upgrade_engine.UPGRADE_FILELOGS, filelogs),
     )
     specified = [(y, x) for (y, x) in specentries if x is not None]
     if specified:
         # we have some limitation on revlogs to be recloned
         if any(x for y, x in specified):
             revlogs = set()
             for upgrade, enabled in specified:
                 if enabled:
                     revlogs.add(upgrade)
         else:
             # none are enabled
             for upgrade, __ in specified:
                 revlogs.discard(upgrade)
 
     # Ensure the repository can be upgraded.
     missingreqs = requiredsourcerequirements(repo) - repo.requirements
     if missingreqs:
         raise error.Abort(
             _(b'cannot upgrade repository; requirement missing: %s')
             % _(b', ').join(sorted(missingreqs))
         )
 
     blockedreqs = blocksourcerequirements(repo) & repo.requirements
     if blockedreqs:
         raise error.Abort(
             _(
                 b'cannot upgrade repository; unsupported source '
                 b'requirement: %s'
             )
             % _(b', ').join(sorted(blockedreqs))
         )
 
     # FUTURE there is potentially a need to control the wanted requirements via
     # command arguments or via an extension hook point.
     newreqs = localrepo.newreporequirements(
         repo.ui, localrepo.defaultcreateopts(repo.ui)
     )
     newreqs.update(preservedrequirements(repo))
 
     noremovereqs = (
         repo.requirements - newreqs - supportremovedrequirements(repo)
     )
     if noremovereqs:
         raise error.Abort(
             _(
                 b'cannot upgrade repository; requirement would be '
                 b'removed: %s'
             )
             % _(b', ').join(sorted(noremovereqs))
         )
 
     noaddreqs = newreqs - repo.requirements - allowednewrequirements(repo)
     if noaddreqs:
         raise error.Abort(
             _(
                 b'cannot upgrade repository; do not support adding '
                 b'requirement: %s'
             )
             % _(b', ').join(sorted(noaddreqs))
         )
 
     unsupportedreqs = newreqs - supporteddestrequirements(repo)
     if unsupportedreqs:
         raise error.Abort(
             _(
                 b'cannot upgrade repository; do not support '
                 b'destination requirement: %s'
             )
             % _(b', ').join(sorted(unsupportedreqs))
         )
 
     # Find and validate all improvements that can be made.
     alloptimizations = findoptimizations(repo)
 
     # Apply and Validate arguments.
     optimizations = []
     for o in alloptimizations:
         if o.name in optimize:
             optimizations.append(o)
             optimize.discard(o.name)
 
     if optimize:  # anything left is unknown
         raise error.Abort(
             _(b'unknown optimization action requested: %s')
             % b', '.join(sorted(optimize)),
             hint=_(b'run without arguments to see valid optimizations'),
         )
 
     deficiencies = finddeficiencies(repo)
     actions = determineactions(repo, deficiencies, repo.requirements, newreqs)
     actions.extend(
         o
         for o in sorted(optimizations)
         # determineactions could have added optimisation
         if o not in actions
     )
 
     removedreqs = repo.requirements - newreqs
     addedreqs = newreqs - repo.requirements
 
-    if revlogs != UPGRADE_ALL_REVLOGS:
+    if revlogs != upgrade_engine.UPGRADE_ALL_REVLOGS:
         incompatible = RECLONES_REQUIREMENTS & (removedreqs | addedreqs)
         if incompatible:
             msg = _(
                 b'ignoring revlogs selection flags, format requirements '
                 b'change: %s\n'
             )
             ui.warn(msg % b', '.join(sorted(incompatible)))
-            revlogs = UPGRADE_ALL_REVLOGS
+            revlogs = upgrade_engine.UPGRADE_ALL_REVLOGS
 
     def write_labeled(l, label):
         first = True
         for r in sorted(l):
             if not first:
                 ui.write(b', ')
             ui.write(r, label=label)
             first = False
 
     def printrequirements():
         ui.write(_(b'requirements\n'))
         ui.write(_(b'   preserved: '))
         write_labeled(
             newreqs & repo.requirements, "upgrade-repo.requirement.preserved"
         )
         ui.write((b'\n'))
         removed = repo.requirements - newreqs
         if repo.requirements - newreqs:
             ui.write(_(b'   removed: '))
             write_labeled(removed, "upgrade-repo.requirement.removed")
             ui.write((b'\n'))
         added = newreqs - repo.requirements
         if added:
             ui.write(_(b'   added: '))
             write_labeled(added, "upgrade-repo.requirement.added")
             ui.write((b'\n'))
         ui.write(b'\n')
 
     def printoptimisations():
         optimisations = [a for a in actions if a.type == OPTIMISATION]
         optimisations.sort(key=lambda a: a.name)
         if optimisations:
             ui.write(_(b'optimisations: '))
             write_labeled(
                 [a.name for a in optimisations],
                 "upgrade-repo.optimisation.performed",
             )
             ui.write(b'\n\n')
 
     def printupgradeactions():
         for a in actions:
             ui.status(b'%s\n   %s\n\n' % (a.name, a.upgrademessage))
 
     def print_affected_revlogs():
         if not revlogs:
             ui.write((b'no revlogs to process\n'))
         else:
             ui.write((b'processed revlogs:\n'))
             for r in sorted(revlogs):
                 ui.write((b'  - %s\n' % r))
         ui.write((b'\n'))
 
     if not run:
         fromconfig = []
         onlydefault = []
 
         for d in deficiencies:
             if d.fromconfig(repo):
                 fromconfig.append(d)
             elif d.default:
                 onlydefault.append(d)
 
         if fromconfig or onlydefault:
 
             if fromconfig:
                 ui.status(
                     _(
                         b'repository lacks features recommended by '
                         b'current config options:\n\n'
                     )
                 )
                 for i in fromconfig:
                     ui.status(b'%s\n   %s\n\n' % (i.name, i.description))
 
             if onlydefault:
                 ui.status(
                     _(
                         b'repository lacks features used by the default '
                         b'config options:\n\n'
                     )
                 )
                 for i in onlydefault:
                     ui.status(b'%s\n   %s\n\n' % (i.name, i.description))
 
             ui.status(b'\n')
         else:
             ui.status(
                 _(
                     b'(no feature deficiencies found in existing '
                     b'repository)\n'
                 )
             )
 
         ui.status(
             _(
                 b'performing an upgrade with "--run" will make the following '
                 b'changes:\n\n'
             )
         )
 
         printrequirements()
         printoptimisations()
         printupgradeactions()
         print_affected_revlogs()
 
         unusedoptimize = [i for i in alloptimizations if i not in actions]
 
         if unusedoptimize:
             ui.status(
                 _(
                     b'additional optimizations are available by specifying '
                     b'"--optimize <name>":\n\n'
                 )
             )
             for i in unusedoptimize:
                 ui.status(_(b'%s\n   %s\n\n') % (i.name, i.description))
         return
 
     # Else we're in the run=true case.
     ui.write(_(b'upgrade will perform the following actions:\n\n'))
     printrequirements()
     printoptimisations()
     printupgradeactions()
     print_affected_revlogs()
 
     upgradeactions = [a.name for a in actions]
 
     ui.status(_(b'beginning upgrade...\n'))
     with repo.wlock(), repo.lock():
         ui.status(_(b'repository locked and read-only\n'))
         # Our strategy for upgrading the repository is to create a new,
         # temporary repository, write data to it, then do a swap of the
         # data. There are less heavyweight ways to do this, but it is easier
         # to create a new repo object than to instantiate all the components
         # (like the store) separately.
         tmppath = pycompat.mkdtemp(prefix=b'upgrade.', dir=repo.path)
         backuppath = None
         try:
             ui.status(
                 _(
                     b'creating temporary repository to stage migrated '
                     b'data: %s\n'
                 )
                 % tmppath
             )
 
             # clone ui without using ui.copy because repo.ui is protected
             repoui = repo.ui.__class__(repo.ui)
             dstrepo = hg.repository(repoui, path=tmppath, create=True)
 
             with dstrepo.wlock(), dstrepo.lock():
-                backuppath = _upgraderepo(
+                backuppath = upgrade_engine.upgrade(
                     ui, repo, dstrepo, newreqs, upgradeactions, revlogs=revlogs
                 )
             if not (backup or backuppath is None):
                 ui.status(
                     _(b'removing old repository content%s\n') % backuppath
                 )
                 repo.vfs.rmtree(backuppath, forcibly=True)
                 backuppath = None
 
         finally:
             ui.status(_(b'removing temporary repository %s\n') % tmppath)
             repo.vfs.rmtree(tmppath, forcibly=True)
 
             if backuppath and not ui.quiet:
                 ui.warn(
                     _(b'copy of old repository backed up at %s\n') % backuppath
                 )
                 ui.warn(
                     _(
                         b'the old repository will not be deleted; remove '
                         b'it to free up disk space once the upgraded '
                         b'repository is verified\n'
                     )
                 )
 
             if sharedsafe.name in addedreqs:
                 ui.warn(
                     _(
                         b'repository upgraded to share safe mode, existing'
                         b' shares will still work in old non-safe mode. '
                         b'Re-share existing shares to use them in safe mode'
                         b' New shares will be created in safe mode.\n'
                     )
                 )
             if sharedsafe.name in removedreqs:
                 ui.warn(
                     _(
                         b'repository downgraded to not use share safe mode, '
                         b'existing shares will not work and needs to'
                         b' be reshared.\n'
                     )
                 )

mercurial/upgrade_utils/engine.py

@@ -1,1492 +1,500 b''
 # upgrade.py - functions for in place upgrade of Mercurial repository
 #
 # Copyright (c) 2016-present, Gregory Szorc
 #
 # 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 stat
 
-from .i18n import _
-from .pycompat import getattr
-from . import (
+from ..i18n import _
+from ..pycompat import getattr
+from .. import (
     changelog,
     error,
     filelog,
-    hg,
-    localrepo,
     manifest,
     metadata,
     pycompat,
     requirements,
     revlog,
     scmutil,
     util,
     vfs as vfsmod,
 )
 
-from .utils import compression
-
-# list of requirements that request a clone of all revlog if added/removed
-RECLONES_REQUIREMENTS = {
-    b'generaldelta',
-    requirements.SPARSEREVLOG_REQUIREMENT,
-}
-
-
-def requiredsourcerequirements(repo):
-    """Obtain requirements required to be present to upgrade a repo.
-
-    An upgrade will not be allowed if the repository doesn't have the
-    requirements returned by this function.
-    """
-    return {
-        # Introduced in Mercurial 0.9.2.
-        b'revlogv1',
-        # Introduced in Mercurial 0.9.2.
-        b'store',
-    }
-
-
-def blocksourcerequirements(repo):
-    """Obtain requirements that will prevent an upgrade from occurring.
-
-    An upgrade cannot be performed if the source repository contains a
-    requirements in the returned set.
-    """
-    return {
-        # The upgrade code does not yet support these experimental features.
-        # This is an artificial limitation.
-        requirements.TREEMANIFEST_REQUIREMENT,
-        # This was a precursor to generaldelta and was never enabled by default.
-        # It should (hopefully) not exist in the wild.
-        b'parentdelta',
-        # Upgrade should operate on the actual store, not the shared link.
-        requirements.SHARED_REQUIREMENT,
-    }
-
-
-def supportremovedrequirements(repo):
-    """Obtain requirements that can be removed during an upgrade.
-
-    If an upgrade were to create a repository that dropped a requirement,
-    the dropped requirement must appear in the returned set for the upgrade
-    to be allowed.
-    """
-    supported = {
-        requirements.SPARSEREVLOG_REQUIREMENT,
-        requirements.SIDEDATA_REQUIREMENT,
-        requirements.COPIESSDC_REQUIREMENT,
-        requirements.NODEMAP_REQUIREMENT,
-        requirements.SHARESAFE_REQUIREMENT,
-    }
-    for name in compression.compengines:
-        engine = compression.compengines[name]
-        if engine.available() and engine.revlogheader():
-            supported.add(b'exp-compression-%s' % name)
-            if engine.name() == b'zstd':
-                supported.add(b'revlog-compression-zstd')
-    return supported
-
-
-def supporteddestrequirements(repo):
-    """Obtain requirements that upgrade supports in the destination.
-
-    If the result of the upgrade would create requirements not in this set,
-    the upgrade is disallowed.
-
-    Extensions should monkeypatch this to add their custom requirements.
-    """
-    supported = {
-        b'dotencode',
-        b'fncache',
-        b'generaldelta',
-        b'revlogv1',
-        b'store',
-        requirements.SPARSEREVLOG_REQUIREMENT,
-        requirements.SIDEDATA_REQUIREMENT,
-        requirements.COPIESSDC_REQUIREMENT,
-        requirements.NODEMAP_REQUIREMENT,
-        requirements.SHARESAFE_REQUIREMENT,
-    }
-    for name in compression.compengines:
-        engine = compression.compengines[name]
-        if engine.available() and engine.revlogheader():
-            supported.add(b'exp-compression-%s' % name)
-            if engine.name() == b'zstd':
-                supported.add(b'revlog-compression-zstd')
-    return supported
-
-
-def allowednewrequirements(repo):
-    """Obtain requirements that can be added to a repository during upgrade.
-
-    This is used to disallow proposed requirements from being added when
-    they weren't present before.
-
-    We use a list of allowed requirement additions instead of a list of known
-    bad additions because the whitelist approach is safer and will prevent
-    future, unknown requirements from accidentally being added.
-    """
-    supported = {
-        b'dotencode',
-        b'fncache',
-        b'generaldelta',
-        requirements.SPARSEREVLOG_REQUIREMENT,
-        requirements.SIDEDATA_REQUIREMENT,
-        requirements.COPIESSDC_REQUIREMENT,
-        requirements.NODEMAP_REQUIREMENT,
-        requirements.SHARESAFE_REQUIREMENT,
-    }
-    for name in compression.compengines:
-        engine = compression.compengines[name]
-        if engine.available() and engine.revlogheader():
-            supported.add(b'exp-compression-%s' % name)
-            if engine.name() == b'zstd':
-                supported.add(b'revlog-compression-zstd')
-    return supported
-
-
-def preservedrequirements(repo):
-    return set()
-
-
-DEFICIENCY = b'deficiency'
-OPTIMISATION = b'optimization'
-
-
-class improvement(object):
-    """Represents an improvement that can be made as part of an upgrade.
-
-    The following attributes are defined on each instance:
-
-    name
-       Machine-readable string uniquely identifying this improvement. It
-       will be mapped to an action later in the upgrade process.
-
-    type
-       Either ``DEFICIENCY`` or ``OPTIMISATION``. A deficiency is an obvious
-       problem. An optimization is an action (sometimes optional) that
-       can be taken to further improve the state of the repository.
-
-    description
-       Message intended for humans explaining the improvement in more detail,
-       including the implications of it. For ``DEFICIENCY`` types, should be
-       worded in the present tense. For ``OPTIMISATION`` types, should be
-       worded in the future tense.
-
-    upgrademessage
-       Message intended for humans explaining what an upgrade addressing this
-       issue will do. Should be worded in the future tense.
-    """
-
-    def __init__(self, name, type, description, upgrademessage):
-        self.name = name
-        self.type = type
-        self.description = description
-        self.upgrademessage = upgrademessage
-
-    def __eq__(self, other):
-        if not isinstance(other, improvement):
-            # This is what python tell use to do
-            return NotImplemented
-        return self.name == other.name
-
-    def __ne__(self, other):
-        return not (self == other)
-
-    def __hash__(self):
-        return hash(self.name)
-
-
-allformatvariant = []
-
-
-def registerformatvariant(cls):
-    allformatvariant.append(cls)
-    return cls
-
-
-class formatvariant(improvement):
-    """an improvement subclass dedicated to repository format"""
-
-    type = DEFICIENCY
-    ### The following attributes should be defined for each class:
-
-    # machine-readable string uniquely identifying this improvement. it will be
-    # mapped to an action later in the upgrade process.
-    name = None
-
-    # message intended for humans explaining the improvement in more detail,
-    # including the implications of it ``DEFICIENCY`` types, should be worded
-    # in the present tense.
-    description = None
-
-    # message intended for humans explaining what an upgrade addressing this
-    # issue will do. should be worded in the future tense.
-    upgrademessage = None
-
-    # value of current Mercurial default for new repository
-    default = None
-
-    def __init__(self):
-        raise NotImplementedError()
-
-    @staticmethod
-    def fromrepo(repo):
-        """current value of the variant in the repository"""
-        raise NotImplementedError()
-
-    @staticmethod
-    def fromconfig(repo):
-        """current value of the variant in the configuration"""
-        raise NotImplementedError()
-
-
-class requirementformatvariant(formatvariant):
-    """formatvariant based on a 'requirement' name.
-
-    Many format variant are controlled by a 'requirement'. We define a small
-    subclass to factor the code.
-    """
-
-    # the requirement that control this format variant
-    _requirement = None
-
-    @staticmethod
-    def _newreporequirements(ui):
-        return localrepo.newreporequirements(
-            ui, localrepo.defaultcreateopts(ui)
-        )
-
-    @classmethod
-    def fromrepo(cls, repo):
-        assert cls._requirement is not None
-        return cls._requirement in repo.requirements
-
-    @classmethod
-    def fromconfig(cls, repo):
-        assert cls._requirement is not None
-        return cls._requirement in cls._newreporequirements(repo.ui)
-
-
-@registerformatvariant
-class fncache(requirementformatvariant):
-    name = b'fncache'
-
-    _requirement = b'fncache'
-
-    default = True
-
-    description = _(
-        b'long and reserved filenames may not work correctly; '
-        b'repository performance is sub-optimal'
-    )
-
-    upgrademessage = _(
-        b'repository will be more resilient to storing '
-        b'certain paths and performance of certain '
-        b'operations should be improved'
-    )
-
-
-@registerformatvariant
-class dotencode(requirementformatvariant):
-    name = b'dotencode'
-
-    _requirement = b'dotencode'
-
-    default = True
-
-    description = _(
-        b'storage of filenames beginning with a period or '
-        b'space may not work correctly'
-    )
-
-    upgrademessage = _(
-        b'repository will be better able to store files '
-        b'beginning with a space or period'
-    )
-
-
-@registerformatvariant
-class generaldelta(requirementformatvariant):
-    name = b'generaldelta'
-
-    _requirement = b'generaldelta'
-
-    default = True
-
-    description = _(
-        b'deltas within internal storage are unable to '
-        b'choose optimal revisions; repository is larger and '
-        b'slower than it could be; interaction with other '
-        b'repositories may require extra network and CPU '
-        b'resources, making "hg push" and "hg pull" slower'
-    )
-
-    upgrademessage = _(
-        b'repository storage will be able to create '
-        b'optimal deltas; new repository data will be '
-        b'smaller and read times should decrease; '
-        b'interacting with other repositories using this '
-        b'storage model should require less network and '
-        b'CPU resources, making "hg push" and "hg pull" '
-        b'faster'
-    )
-
-
-@registerformatvariant
-class sharedsafe(requirementformatvariant):
-    name = b'exp-sharesafe'
-    _requirement = requirements.SHARESAFE_REQUIREMENT
-
-    default = False
-
-    description = _(
-        b'old shared repositories do not share source repository '
-        b'requirements and config. This leads to various problems '
-        b'when the source repository format is upgraded or some new '
-        b'extensions are enabled.'
-    )
-
-    upgrademessage = _(
-        b'Upgrades a repository to share-safe format so that future '
-        b'shares of this repository share its requirements and configs.'
-    )
-
-
-@registerformatvariant
-class sparserevlog(requirementformatvariant):
-    name = b'sparserevlog'
-
-    _requirement = requirements.SPARSEREVLOG_REQUIREMENT
-
-    default = True
-
-    description = _(
-        b'in order to limit disk reading and memory usage on older '
-        b'version, the span of a delta chain from its root to its '
-        b'end is limited, whatever the relevant data in this span. '
-        b'This can severly limit Mercurial ability to build good '
-        b'chain of delta resulting is much more storage space being '
-        b'taken and limit reusability of on disk delta during '
-        b'exchange.'
-    )
-
-    upgrademessage = _(
-        b'Revlog supports delta chain with more unused data '
-        b'between payload. These gaps will be skipped at read '
-        b'time. This allows for better delta chains, making a '
-        b'better compression and faster exchange with server.'
-    )
-
-
-@registerformatvariant
-class sidedata(requirementformatvariant):
-    name = b'sidedata'
-
-    _requirement = requirements.SIDEDATA_REQUIREMENT
-
-    default = False
-
-    description = _(
-        b'Allows storage of extra data alongside a revision, '
-        b'unlocking various caching options.'
-    )
-
-    upgrademessage = _(b'Allows storage of extra data alongside a revision.')
-
-
-@registerformatvariant
-class persistentnodemap(requirementformatvariant):
-    name = b'persistent-nodemap'
-
-    _requirement = requirements.NODEMAP_REQUIREMENT
-
-    default = False
-
-    description = _(
-        b'persist the node -> rev mapping on disk to speedup lookup'
-    )
-
-    upgrademessage = _(b'Speedup revision lookup by node id.')
-
-
-@registerformatvariant
-class copiessdc(requirementformatvariant):
-    name = b'copies-sdc'
-
-    _requirement = requirements.COPIESSDC_REQUIREMENT
-
-    default = False
-
-    description = _(b'Stores copies information alongside changesets.')
-
-    upgrademessage = _(
-        b'Allows to use more efficient algorithm to deal with ' b'copy tracing.'
-    )
-
-
-@registerformatvariant
-class removecldeltachain(formatvariant):
-    name = b'plain-cl-delta'
-
-    default = True
-
-    description = _(
-        b'changelog storage is using deltas instead of '
-        b'raw entries; changelog reading and any '
-        b'operation relying on changelog data are slower '
-        b'than they could be'
-    )
-
-    upgrademessage = _(
-        b'changelog storage will be reformated to '
-        b'store raw entries; changelog reading will be '
-        b'faster; changelog size may be reduced'
-    )
-
-    @staticmethod
-    def fromrepo(repo):
-        # Mercurial 4.0 changed changelogs to not use delta chains. Search for
-        # changelogs with deltas.
-        cl = repo.changelog
-        chainbase = cl.chainbase
-        return all(rev == chainbase(rev) for rev in cl)
-
-    @staticmethod
-    def fromconfig(repo):
-        return True
-
-
-@registerformatvariant
-class compressionengine(formatvariant):
-    name = b'compression'
-    default = b'zlib'
-
-    description = _(
-        b'Compresion algorithm used to compress data. '
-        b'Some engine are faster than other'
-    )
-
-    upgrademessage = _(
-        b'revlog content will be recompressed with the new algorithm.'
-    )
-
-    @classmethod
-    def fromrepo(cls, repo):
-        # we allow multiple compression engine requirement to co-exist because
-        # strickly speaking, revlog seems to support mixed compression style.
-        #
-        # The compression used for new entries will be "the last one"
-        compression = b'zlib'
-        for req in repo.requirements:
-            prefix = req.startswith
-            if prefix(b'revlog-compression-') or prefix(b'exp-compression-'):
-                compression = req.split(b'-', 2)[2]
-        return compression
-
-    @classmethod
-    def fromconfig(cls, repo):
-        compengines = repo.ui.configlist(b'format', b'revlog-compression')
-        # return the first valid value as the selection code would do
-        for comp in compengines:
-            if comp in util.compengines:
-                return comp
-
-        # no valide compression found lets display it all for clarity
-        return b','.join(compengines)
-
-
-@registerformatvariant
-class compressionlevel(formatvariant):
-    name = b'compression-level'
-    default = b'default'
-
-    description = _(b'compression level')
-
-    upgrademessage = _(b'revlog content will be recompressed')
-
-    @classmethod
-    def fromrepo(cls, repo):
-        comp = compressionengine.fromrepo(repo)
-        level = None
-        if comp == b'zlib':
-            level = repo.ui.configint(b'storage', b'revlog.zlib.level')
-        elif comp == b'zstd':
-            level = repo.ui.configint(b'storage', b'revlog.zstd.level')
-        if level is None:
-            return b'default'
-        return bytes(level)
-
-    @classmethod
-    def fromconfig(cls, repo):
-        comp = compressionengine.fromconfig(repo)
-        level = None
-        if comp == b'zlib':
-            level = repo.ui.configint(b'storage', b'revlog.zlib.level')
-        elif comp == b'zstd':
-            level = repo.ui.configint(b'storage', b'revlog.zstd.level')
-        if level is None:
-            return b'default'
-        return bytes(level)
-
-
-def finddeficiencies(repo):
-    """returns a list of deficiencies that the repo suffer from"""
-    deficiencies = []
-
-    # We could detect lack of revlogv1 and store here, but they were added
-    # in 0.9.2 and we don't support upgrading repos without these
-    # requirements, so let's not bother.
-
-    for fv in allformatvariant:
-        if not fv.fromrepo(repo):
-            deficiencies.append(fv)
-
-    return deficiencies
-
-
-# search without '-' to support older form on newer client.
-#
-# We don't enforce backward compatibility for debug command so this
-# might eventually be dropped. However, having to use two different
-# forms in script when comparing result is anoying enough to add
-# backward compatibility for a while.
-legacy_opts_map = {
-    b'redeltaparent': b're-delta-parent',
-    b'redeltamultibase': b're-delta-multibase',
-    b'redeltaall': b're-delta-all',
-    b'redeltafulladd': b're-delta-fulladd',
-}
-
-ALL_OPTIMISATIONS = []
-
-
-def register_optimization(obj):
-    ALL_OPTIMISATIONS.append(obj)
-    return obj
-
-
-register_optimization(
-    improvement(
-        name=b're-delta-parent',
-        type=OPTIMISATION,
-        description=_(
-            b'deltas within internal storage will be recalculated to '
-            b'choose an optimal base revision where this was not '
-            b'already done; the size of the repository may shrink and '
-            b'various operations may become faster; the first time '
-            b'this optimization is performed could slow down upgrade '
-            b'execution considerably; subsequent invocations should '
-            b'not run noticeably slower'
-        ),
-        upgrademessage=_(
-            b'deltas within internal storage will choose a new '
-            b'base revision if needed'
-        ),
-    )
-)
-
-register_optimization(
-    improvement(
-        name=b're-delta-multibase',
-        type=OPTIMISATION,
-        description=_(
-            b'deltas within internal storage will be recalculated '
-            b'against multiple base revision and the smallest '
-            b'difference will be used; the size of the repository may '
-            b'shrink significantly when there are many merges; this '
-            b'optimization will slow down execution in proportion to '
-            b'the number of merges in the repository and the amount '
-            b'of files in the repository; this slow down should not '
-            b'be significant unless there are tens of thousands of '
-            b'files and thousands of merges'
-        ),
-        upgrademessage=_(
-            b'deltas within internal storage will choose an '
-            b'optimal delta by computing deltas against multiple '
-            b'parents; may slow down execution time '
-            b'significantly'
-        ),
-    )
-)
-
-register_optimization(
-    improvement(
-        name=b're-delta-all',
-        type=OPTIMISATION,
-        description=_(
-            b'deltas within internal storage will always be '
-            b'recalculated without reusing prior deltas; this will '
-            b'likely make execution run several times slower; this '
-            b'optimization is typically not needed'
-        ),
-        upgrademessage=_(
-            b'deltas within internal storage will be fully '
-            b'recomputed; this will likely drastically slow down '
-            b'execution time'
-        ),
-    )
-)
-
-register_optimization(
-    improvement(
-        name=b're-delta-fulladd',
-        type=OPTIMISATION,
-        description=_(
-            b'every revision will be re-added as if it was new '
-            b'content. It will go through the full storage '
-            b'mechanism giving extensions a chance to process it '
-            b'(eg. lfs). This is similar to "re-delta-all" but even '
-            b'slower since more logic is involved.'
-        ),
-        upgrademessage=_(
-            b'each revision will be added as new content to the '
-            b'internal storage; this will likely drastically slow '
-            b'down execution time, but some extensions might need '
-            b'it'
-        ),
-    )
-)
-
-
-def findoptimizations(repo):
-    """Determine optimisation that could be used during upgrade"""
-    # These are unconditionally added. There is logic later that figures out
-    # which ones to apply.
-    return list(ALL_OPTIMISATIONS)
-
-
-def determineactions(repo, deficiencies, sourcereqs, destreqs):
-    """Determine upgrade actions that will be performed.
-
-    Given a list of improvements as returned by ``finddeficiencies`` and
-    ``findoptimizations``, determine the list of upgrade actions that
-    will be performed.
-
-    The role of this function is to filter improvements if needed, apply
-    recommended optimizations from the improvements list that make sense,
-    etc.
-
-    Returns a list of action names.
-    """
-    newactions = []
-
-    for d in deficiencies:
-        name = d._requirement
-
-        # If the action is a requirement that doesn't show up in the
-        # destination requirements, prune the action.
-        if name is not None and name not in destreqs:
-            continue
-
-        newactions.append(d)
-
-    # FUTURE consider adding some optimizations here for certain transitions.
-    # e.g. adding generaldelta could schedule parent redeltas.
-
-    return newactions
-
 
 def _revlogfrompath(repo, path):
     """Obtain a revlog from a repo path.
 
     An instance of the appropriate class is returned.
     """
     if path == b'00changelog.i':
         return changelog.changelog(repo.svfs)
     elif path.endswith(b'00manifest.i'):
         mandir = path[: -len(b'00manifest.i')]
         return manifest.manifestrevlog(repo.svfs, tree=mandir)
     else:
         # reverse of "/".join(("data", path + ".i"))
         return filelog.filelog(repo.svfs, path[5:-2])
 
 
 def _copyrevlog(tr, destrepo, oldrl, unencodedname):
     """copy all relevant files for `oldrl` into `destrepo` store
 
     Files are copied "as is" without any transformation. The copy is performed
     without extra checks. Callers are responsible for making sure the copied
     content is compatible with format of the destination repository.
     """
     oldrl = getattr(oldrl, '_revlog', oldrl)
     newrl = _revlogfrompath(destrepo, unencodedname)
     newrl = getattr(newrl, '_revlog', newrl)
 
     oldvfs = oldrl.opener
     newvfs = newrl.opener
     oldindex = oldvfs.join(oldrl.indexfile)
     newindex = newvfs.join(newrl.indexfile)
     olddata = oldvfs.join(oldrl.datafile)
     newdata = newvfs.join(newrl.datafile)
 
     with newvfs(newrl.indexfile, b'w'):
         pass  # create all the directories
 
     util.copyfile(oldindex, newindex)
     copydata = oldrl.opener.exists(oldrl.datafile)
     if copydata:
         util.copyfile(olddata, newdata)
 
     if not (
         unencodedname.endswith(b'00changelog.i')
         or unencodedname.endswith(b'00manifest.i')
     ):
         destrepo.svfs.fncache.add(unencodedname)
         if copydata:
             destrepo.svfs.fncache.add(unencodedname[:-2] + b'.d')
 
 
 UPGRADE_CHANGELOG = b"changelog"
 UPGRADE_MANIFEST = b"manifest"
 UPGRADE_FILELOGS = b"all-filelogs"
 
 UPGRADE_ALL_REVLOGS = frozenset(
     [UPGRADE_CHANGELOG, UPGRADE_MANIFEST, UPGRADE_FILELOGS]
 )
 
 
 def getsidedatacompanion(srcrepo, dstrepo):
     sidedatacompanion = None
     removedreqs = srcrepo.requirements - dstrepo.requirements
     addedreqs = dstrepo.requirements - srcrepo.requirements
     if requirements.SIDEDATA_REQUIREMENT in removedreqs:
 
         def sidedatacompanion(rl, rev):
             rl = getattr(rl, '_revlog', rl)
             if rl.flags(rev) & revlog.REVIDX_SIDEDATA:
                 return True, (), {}, 0, 0
             return False, (), {}, 0, 0
 
     elif requirements.COPIESSDC_REQUIREMENT in addedreqs:
         sidedatacompanion = metadata.getsidedataadder(srcrepo, dstrepo)
     elif requirements.COPIESSDC_REQUIREMENT in removedreqs:
         sidedatacompanion = metadata.getsidedataremover(srcrepo, dstrepo)
     return sidedatacompanion
 
 
 def matchrevlog(revlogfilter, entry):
     """check if a revlog is selected for cloning.
 
     In other words, are there any updates which need to be done on revlog
     or it can be blindly copied.
 
     The store entry is checked against the passed filter"""
     if entry.endswith(b'00changelog.i'):
         return UPGRADE_CHANGELOG in revlogfilter
     elif entry.endswith(b'00manifest.i'):
         return UPGRADE_MANIFEST in revlogfilter
     return UPGRADE_FILELOGS in revlogfilter
 
 
 def _clonerevlogs(
     ui,
     srcrepo,
     dstrepo,
     tr,
     deltareuse,
     forcedeltabothparents,
     revlogs=UPGRADE_ALL_REVLOGS,
 ):
     """Copy revlogs between 2 repos."""
     revcount = 0
     srcsize = 0
     srcrawsize = 0
     dstsize = 0
     fcount = 0
     frevcount = 0
     fsrcsize = 0
     frawsize = 0
     fdstsize = 0
     mcount = 0
     mrevcount = 0
     msrcsize = 0
     mrawsize = 0
     mdstsize = 0
     crevcount = 0
     csrcsize = 0
     crawsize = 0
     cdstsize = 0
 
     alldatafiles = list(srcrepo.store.walk())
 
     # Perform a pass to collect metadata. This validates we can open all
     # source files and allows a unified progress bar to be displayed.
     for unencoded, encoded, size in alldatafiles:
         if unencoded.endswith(b'.d'):
             continue
 
         rl = _revlogfrompath(srcrepo, unencoded)
 
         info = rl.storageinfo(
             exclusivefiles=True,
             revisionscount=True,
             trackedsize=True,
             storedsize=True,
         )
 
         revcount += info[b'revisionscount'] or 0
         datasize = info[b'storedsize'] or 0
         rawsize = info[b'trackedsize'] or 0
 
         srcsize += datasize
         srcrawsize += rawsize
 
         # This is for the separate progress bars.
         if isinstance(rl, changelog.changelog):
             crevcount += len(rl)
             csrcsize += datasize
             crawsize += rawsize
         elif isinstance(rl, manifest.manifestrevlog):
             mcount += 1
             mrevcount += len(rl)
             msrcsize += datasize
             mrawsize += rawsize
         elif isinstance(rl, filelog.filelog):
             fcount += 1
             frevcount += len(rl)
             fsrcsize += datasize
             frawsize += rawsize
         else:
             error.ProgrammingError(b'unknown revlog type')
 
     if not revcount:
         return
 
     ui.status(
         _(
             b'migrating %d total revisions (%d in filelogs, %d in manifests, '
             b'%d in changelog)\n'
         )
         % (revcount, frevcount, mrevcount, crevcount)
     )
     ui.status(
         _(b'migrating %s in store; %s tracked data\n')
         % ((util.bytecount(srcsize), util.bytecount(srcrawsize)))
     )
 
     # Used to keep track of progress.
     progress = None
 
     def oncopiedrevision(rl, rev, node):
         progress.increment()
 
     sidedatacompanion = getsidedatacompanion(srcrepo, dstrepo)
 
     # Do the actual copying.
     # FUTURE this operation can be farmed off to worker processes.
     seen = set()
     for unencoded, encoded, size in alldatafiles:
         if unencoded.endswith(b'.d'):
             continue
 
         oldrl = _revlogfrompath(srcrepo, unencoded)
 
         if isinstance(oldrl, changelog.changelog) and b'c' not in seen:
             ui.status(
                 _(
                     b'finished migrating %d manifest revisions across %d '
                     b'manifests; change in size: %s\n'
                 )
                 % (mrevcount, mcount, util.bytecount(mdstsize - msrcsize))
             )
 
             ui.status(
                 _(
                     b'migrating changelog containing %d revisions '
                     b'(%s in store; %s tracked data)\n'
                 )
                 % (
                     crevcount,
                     util.bytecount(csrcsize),
                     util.bytecount(crawsize),
                 )
             )
             seen.add(b'c')
             progress = srcrepo.ui.makeprogress(
                 _(b'changelog revisions'), total=crevcount
             )
         elif isinstance(oldrl, manifest.manifestrevlog) and b'm' not in seen:
             ui.status(
                 _(
                     b'finished migrating %d filelog revisions across %d '
                     b'filelogs; change in size: %s\n'
                 )
                 % (frevcount, fcount, util.bytecount(fdstsize - fsrcsize))
             )
 
             ui.status(
                 _(
                     b'migrating %d manifests containing %d revisions '
                     b'(%s in store; %s tracked data)\n'
                 )
                 % (
                     mcount,
                     mrevcount,
                     util.bytecount(msrcsize),
                     util.bytecount(mrawsize),
                 )
             )
             seen.add(b'm')
             if progress:
                 progress.complete()
             progress = srcrepo.ui.makeprogress(
                 _(b'manifest revisions'), total=mrevcount
             )
         elif b'f' not in seen:
             ui.status(
                 _(
                     b'migrating %d filelogs containing %d revisions '
                     b'(%s in store; %s tracked data)\n'
                 )
                 % (
                     fcount,
                     frevcount,
                     util.bytecount(fsrcsize),
                     util.bytecount(frawsize),
                 )
             )
             seen.add(b'f')
             if progress:
                 progress.complete()
             progress = srcrepo.ui.makeprogress(
                 _(b'file revisions'), total=frevcount
             )
 
         if matchrevlog(revlogs, unencoded):
             ui.note(
                 _(b'cloning %d revisions from %s\n') % (len(oldrl), unencoded)
             )
             newrl = _revlogfrompath(dstrepo, unencoded)
             oldrl.clone(
                 tr,
                 newrl,
                 addrevisioncb=oncopiedrevision,
                 deltareuse=deltareuse,
                 forcedeltabothparents=forcedeltabothparents,
                 sidedatacompanion=sidedatacompanion,
             )
         else:
             msg = _(b'blindly copying %s containing %i revisions\n')
             ui.note(msg % (unencoded, len(oldrl)))
             _copyrevlog(tr, dstrepo, oldrl, unencoded)
 
             newrl = _revlogfrompath(dstrepo, unencoded)
 
         info = newrl.storageinfo(storedsize=True)
         datasize = info[b'storedsize'] or 0
 
         dstsize += datasize
 
         if isinstance(newrl, changelog.changelog):
             cdstsize += datasize
         elif isinstance(newrl, manifest.manifestrevlog):
             mdstsize += datasize
         else:
             fdstsize += datasize
 
     progress.complete()
 
     ui.status(
         _(
             b'finished migrating %d changelog revisions; change in size: '
             b'%s\n'
         )
         % (crevcount, util.bytecount(cdstsize - csrcsize))
     )
 
     ui.status(
         _(
             b'finished migrating %d total revisions; total change in store '
             b'size: %s\n'
         )
         % (revcount, util.bytecount(dstsize - srcsize))
     )
 
 
 def _filterstorefile(srcrepo, dstrepo, requirements, path, mode, st):
     """Determine whether to copy a store file during upgrade.
 
     This function is called when migrating store files from ``srcrepo`` to
     ``dstrepo`` as part of upgrading a repository.
 
     Args:
       srcrepo: repo we are copying from
       dstrepo: repo we are copying to
       requirements: set of requirements for ``dstrepo``
       path: store file being examined
       mode: the ``ST_MODE`` file type of ``path``
       st: ``stat`` data structure for ``path``
 
     Function should return ``True`` if the file is to be copied.
     """
     # Skip revlogs.
     if path.endswith((b'.i', b'.d', b'.n', b'.nd')):
         return False
     # Skip transaction related files.
     if path.startswith(b'undo'):
         return False
     # Only copy regular files.
     if mode != stat.S_IFREG:
         return False
     # Skip other skipped files.
     if path in (b'lock', b'fncache'):
         return False
 
     return True
 
 
 def _finishdatamigration(ui, srcrepo, dstrepo, requirements):
     """Hook point for extensions to perform additional actions during upgrade.
 
     This function is called after revlogs and store files have been copied but
     before the new store is swapped into the original location.
     """
 
 
-def _upgraderepo(
+def upgrade(
     ui, srcrepo, dstrepo, requirements, actions, revlogs=UPGRADE_ALL_REVLOGS
 ):
     """Do the low-level work of upgrading a repository.
 
     The upgrade is effectively performed as a copy between a source
     repository and a temporary destination repository.
 
     The source repository is unmodified for as long as possible so the
     upgrade can abort at any time without causing loss of service for
     readers and without corrupting the source repository.
     """
     assert srcrepo.currentwlock()
     assert dstrepo.currentwlock()
 
     ui.status(
         _(
             b'(it is safe to interrupt this process any time before '
             b'data migration completes)\n'
         )
     )
 
     if b're-delta-all' in actions:
         deltareuse = revlog.revlog.DELTAREUSENEVER
     elif b're-delta-parent' in actions:
         deltareuse = revlog.revlog.DELTAREUSESAMEREVS
     elif b're-delta-multibase' in actions:
         deltareuse = revlog.revlog.DELTAREUSESAMEREVS
     elif b're-delta-fulladd' in actions:
         deltareuse = revlog.revlog.DELTAREUSEFULLADD
     else:
         deltareuse = revlog.revlog.DELTAREUSEALWAYS
 
     with dstrepo.transaction(b'upgrade') as tr:
         _clonerevlogs(
             ui,
             srcrepo,
             dstrepo,
             tr,
             deltareuse,
             b're-delta-multibase' in actions,
             revlogs=revlogs,
         )
 
     # Now copy other files in the store directory.
     # The sorted() makes execution deterministic.
     for p, kind, st in sorted(srcrepo.store.vfs.readdir(b'', stat=True)):
         if not _filterstorefile(srcrepo, dstrepo, requirements, p, kind, st):
             continue
 
         srcrepo.ui.status(_(b'copying %s\n') % p)
         src = srcrepo.store.rawvfs.join(p)
         dst = dstrepo.store.rawvfs.join(p)
         util.copyfile(src, dst, copystat=True)
 
     _finishdatamigration(ui, srcrepo, dstrepo, requirements)
 
     ui.status(_(b'data fully migrated to temporary repository\n'))
 
     backuppath = pycompat.mkdtemp(prefix=b'upgradebackup.', dir=srcrepo.path)
     backupvfs = vfsmod.vfs(backuppath)
 
     # Make a backup of requires file first, as it is the first to be modified.
     util.copyfile(srcrepo.vfs.join(b'requires'), backupvfs.join(b'requires'))
 
     # We install an arbitrary requirement that clients must not support
     # as a mechanism to lock out new clients during the data swap. This is
     # better than allowing a client to continue while the repository is in
     # an inconsistent state.
     ui.status(
         _(
             b'marking source repository as being upgraded; clients will be '
             b'unable to read from repository\n'
         )
     )
     scmutil.writereporequirements(
         srcrepo, srcrepo.requirements | {b'upgradeinprogress'}
     )
 
     ui.status(_(b'starting in-place swap of repository data\n'))
     ui.status(_(b'replaced files will be backed up at %s\n') % backuppath)
 
     # Now swap in the new store directory. Doing it as a rename should make
     # the operation nearly instantaneous and atomic (at least in well-behaved
     # environments).
     ui.status(_(b'replacing store...\n'))
     tstart = util.timer()
     util.rename(srcrepo.spath, backupvfs.join(b'store'))
     util.rename(dstrepo.spath, srcrepo.spath)
     elapsed = util.timer() - tstart
     ui.status(
         _(
             b'store replacement complete; repository was inconsistent for '
             b'%0.1fs\n'
         )
         % elapsed
     )
 
     # We first write the requirements file. Any new requirements will lock
     # out legacy clients.
     ui.status(
         _(
             b'finalizing requirements file and making repository readable '
             b'again\n'
         )
     )
     scmutil.writereporequirements(srcrepo, requirements)
 
     # The lock file from the old store won't be removed because nothing has a
     # reference to its new location. So clean it up manually. Alternatively, we
     # could update srcrepo.svfs and other variables to point to the new
     # location. This is simpler.
     backupvfs.unlink(b'store/lock')
 
     return backuppath
-
-
-def upgraderepo(
-    ui,
-    repo,
-    run=False,
-    optimize=None,
-    backup=True,
-    manifest=None,
-    changelog=None,
-    filelogs=None,
-):
-    """Upgrade a repository in place."""
-    if optimize is None:
-        optimize = []
-    optimize = {legacy_opts_map.get(o, o) for o in optimize}
-    repo = repo.unfiltered()
-
-    revlogs = set(UPGRADE_ALL_REVLOGS)
-    specentries = (
-        (UPGRADE_CHANGELOG, changelog),
-        (UPGRADE_MANIFEST, manifest),
-        (UPGRADE_FILELOGS, filelogs),
-    )
-    specified = [(y, x) for (y, x) in specentries if x is not None]
-    if specified:
-        # we have some limitation on revlogs to be recloned
-        if any(x for y, x in specified):
-            revlogs = set()
-            for upgrade, enabled in specified:
-                if enabled:
-                    revlogs.add(upgrade)
-        else:
-            # none are enabled
-            for upgrade, __ in specified:
-                revlogs.discard(upgrade)
-
-    # Ensure the repository can be upgraded.
-    missingreqs = requiredsourcerequirements(repo) - repo.requirements
-    if missingreqs:
-        raise error.Abort(
-            _(b'cannot upgrade repository; requirement missing: %s')
-            % _(b', ').join(sorted(missingreqs))
-        )
-
-    blockedreqs = blocksourcerequirements(repo) & repo.requirements
-    if blockedreqs:
-        raise error.Abort(
-            _(
-                b'cannot upgrade repository; unsupported source '
-                b'requirement: %s'
-            )
-            % _(b', ').join(sorted(blockedreqs))
-        )
-
-    # FUTURE there is potentially a need to control the wanted requirements via
-    # command arguments or via an extension hook point.
-    newreqs = localrepo.newreporequirements(
-        repo.ui, localrepo.defaultcreateopts(repo.ui)
-    )
-    newreqs.update(preservedrequirements(repo))
-
-    noremovereqs = (
-        repo.requirements - newreqs - supportremovedrequirements(repo)
-    )
-    if noremovereqs:
-        raise error.Abort(
-            _(
-                b'cannot upgrade repository; requirement would be '
-                b'removed: %s'
-            )
-            % _(b', ').join(sorted(noremovereqs))
-        )
-
-    noaddreqs = newreqs - repo.requirements - allowednewrequirements(repo)
-    if noaddreqs:
-        raise error.Abort(
-            _(
-                b'cannot upgrade repository; do not support adding '
-                b'requirement: %s'
-            )
-            % _(b', ').join(sorted(noaddreqs))
-        )
-
-    unsupportedreqs = newreqs - supporteddestrequirements(repo)
-    if unsupportedreqs:
-        raise error.Abort(
-            _(
-                b'cannot upgrade repository; do not support '
-                b'destination requirement: %s'
-            )
-            % _(b', ').join(sorted(unsupportedreqs))
-        )
-
-    # Find and validate all improvements that can be made.
-    alloptimizations = findoptimizations(repo)
-
-    # Apply and Validate arguments.
-    optimizations = []
-    for o in alloptimizations:
-        if o.name in optimize:
-            optimizations.append(o)
-            optimize.discard(o.name)
-
-    if optimize:  # anything left is unknown
-        raise error.Abort(
-            _(b'unknown optimization action requested: %s')
-            % b', '.join(sorted(optimize)),
-            hint=_(b'run without arguments to see valid optimizations'),
-        )
-
-    deficiencies = finddeficiencies(repo)
-    actions = determineactions(repo, deficiencies, repo.requirements, newreqs)
-    actions.extend(
-        o
-        for o in sorted(optimizations)
-        # determineactions could have added optimisation
-        if o not in actions
-    )
-
-    removedreqs = repo.requirements - newreqs
-    addedreqs = newreqs - repo.requirements
-
-    if revlogs != UPGRADE_ALL_REVLOGS:
-        incompatible = RECLONES_REQUIREMENTS & (removedreqs | addedreqs)
-        if incompatible:
-            msg = _(
-                b'ignoring revlogs selection flags, format requirements '
-                b'change: %s\n'
-            )
-            ui.warn(msg % b', '.join(sorted(incompatible)))
-            revlogs = UPGRADE_ALL_REVLOGS
-
-    def write_labeled(l, label):
-        first = True
-        for r in sorted(l):
-            if not first:
-                ui.write(b', ')
-            ui.write(r, label=label)
-            first = False
-
-    def printrequirements():
-        ui.write(_(b'requirements\n'))
-        ui.write(_(b'   preserved: '))
-        write_labeled(
-            newreqs & repo.requirements, "upgrade-repo.requirement.preserved"
-        )
-        ui.write((b'\n'))
-        removed = repo.requirements - newreqs
-        if repo.requirements - newreqs:
-            ui.write(_(b'   removed: '))
-            write_labeled(removed, "upgrade-repo.requirement.removed")
-            ui.write((b'\n'))
-        added = newreqs - repo.requirements
-        if added:
-            ui.write(_(b'   added: '))
-            write_labeled(added, "upgrade-repo.requirement.added")
-            ui.write((b'\n'))
-        ui.write(b'\n')
-
-    def printoptimisations():
-        optimisations = [a for a in actions if a.type == OPTIMISATION]
-        optimisations.sort(key=lambda a: a.name)
-        if optimisations:
-            ui.write(_(b'optimisations: '))
-            write_labeled(
-                [a.name for a in optimisations],
-                "upgrade-repo.optimisation.performed",
-            )
-            ui.write(b'\n\n')
-
-    def printupgradeactions():
-        for a in actions:
-            ui.status(b'%s\n   %s\n\n' % (a.name, a.upgrademessage))
-
-    def print_affected_revlogs():
-        if not revlogs:
-            ui.write((b'no revlogs to process\n'))
-        else:
-            ui.write((b'processed revlogs:\n'))
-            for r in sorted(revlogs):
-                ui.write((b'  - %s\n' % r))
-        ui.write((b'\n'))
-
-    if not run:
-        fromconfig = []
-        onlydefault = []
-
-        for d in deficiencies:
-            if d.fromconfig(repo):
-                fromconfig.append(d)
-            elif d.default:
-                onlydefault.append(d)
-
-        if fromconfig or onlydefault:
-
-            if fromconfig:
-                ui.status(
-                    _(
-                        b'repository lacks features recommended by '
-                        b'current config options:\n\n'
-                    )
-                )
-                for i in fromconfig:
-                    ui.status(b'%s\n   %s\n\n' % (i.name, i.description))
-
-            if onlydefault:
-                ui.status(
-                    _(
-                        b'repository lacks features used by the default '
-                        b'config options:\n\n'
-                    )
-                )
-                for i in onlydefault:
-                    ui.status(b'%s\n   %s\n\n' % (i.name, i.description))
-
-            ui.status(b'\n')
-        else:
-            ui.status(
-                _(
-                    b'(no feature deficiencies found in existing '
-                    b'repository)\n'
-                )
-            )
-
-        ui.status(
-            _(
-                b'performing an upgrade with "--run" will make the following '
-                b'changes:\n\n'
-            )
-        )
-
-        printrequirements()
-        printoptimisations()
-        printupgradeactions()
-        print_affected_revlogs()
-
-        unusedoptimize = [i for i in alloptimizations if i not in actions]
-
-        if unusedoptimize:
-            ui.status(
-                _(
-                    b'additional optimizations are available by specifying '
-                    b'"--optimize <name>":\n\n'
-                )
-            )
-            for i in unusedoptimize:
-                ui.status(_(b'%s\n   %s\n\n') % (i.name, i.description))
-        return
-
-    # Else we're in the run=true case.
-    ui.write(_(b'upgrade will perform the following actions:\n\n'))
-    printrequirements()
-    printoptimisations()
-    printupgradeactions()
-    print_affected_revlogs()
-
-    upgradeactions = [a.name for a in actions]
-
-    ui.status(_(b'beginning upgrade...\n'))
-    with repo.wlock(), repo.lock():
-        ui.status(_(b'repository locked and read-only\n'))
-        # Our strategy for upgrading the repository is to create a new,
-        # temporary repository, write data to it, then do a swap of the
-        # data. There are less heavyweight ways to do this, but it is easier
-        # to create a new repo object than to instantiate all the components
-        # (like the store) separately.
-        tmppath = pycompat.mkdtemp(prefix=b'upgrade.', dir=repo.path)
-        backuppath = None
-        try:
-            ui.status(
-                _(
-                    b'creating temporary repository to stage migrated '
-                    b'data: %s\n'
-                )
-                % tmppath
-            )
-
-            # clone ui without using ui.copy because repo.ui is protected
-            repoui = repo.ui.__class__(repo.ui)
-            dstrepo = hg.repository(repoui, path=tmppath, create=True)
-
-            with dstrepo.wlock(), dstrepo.lock():
-                backuppath = _upgraderepo(
-                    ui, repo, dstrepo, newreqs, upgradeactions, revlogs=revlogs
-                )
-            if not (backup or backuppath is None):
-                ui.status(
-                    _(b'removing old repository content%s\n') % backuppath
-                )
-                repo.vfs.rmtree(backuppath, forcibly=True)
-                backuppath = None
-
-        finally:
-            ui.status(_(b'removing temporary repository %s\n') % tmppath)
-            repo.vfs.rmtree(tmppath, forcibly=True)
-
-            if backuppath and not ui.quiet:
-                ui.warn(
-                    _(b'copy of old repository backed up at %s\n') % backuppath
-                )
-                ui.warn(
-                    _(
-                        b'the old repository will not be deleted; remove '
-                        b'it to free up disk space once the upgraded '
-                        b'repository is verified\n'
-                    )
-                )
-
-            if sharedsafe.name in addedreqs:
-                ui.warn(
-                    _(
-                        b'repository upgraded to share safe mode, existing'
-                        b' shares will still work in old non-safe mode. '
-                        b'Re-share existing shares to use them in safe mode'
-                        b' New shares will be created in safe mode.\n'
-                    )
-                )
-            if sharedsafe.name in removedreqs:
-                ui.warn(
-                    _(
-                        b'repository downgraded to not use share safe mode, '
-                        b'existing shares will not work and needs to'
-                        b' be reshared.\n'
-                    )
-                )

setup.py

@@ -1,1827 +1,1828 b''
 #
 # This is the mercurial setup script.
 #
 # 'python setup.py install', or
 # 'python setup.py --help' for more options
 import os
 
 # Mercurial will never work on Python 3 before 3.5 due to a lack
 # of % formatting on bytestrings, and can't work on 3.6.0 or 3.6.1
 # due to a bug in % formatting in bytestrings.
 # We cannot support Python 3.5.0, 3.5.1, 3.5.2 because of bug in
 # codecs.escape_encode() where it raises SystemError on empty bytestring
 # bug link: https://bugs.python.org/issue25270
 supportedpy = ','.join(
     [
         '>=2.7.4',
         '!=3.0.*',
         '!=3.1.*',
         '!=3.2.*',
         '!=3.3.*',
         '!=3.4.*',
         '!=3.5.0',
         '!=3.5.1',
         '!=3.5.2',
         '!=3.6.0',
         '!=3.6.1',
     ]
 )
 
 import sys, platform
 import sysconfig
 
 if sys.version_info[0] >= 3:
     printf = eval('print')
     libdir_escape = 'unicode_escape'
 
     def sysstr(s):
         return s.decode('latin-1')
 
 
 else:
     libdir_escape = 'string_escape'
 
     def printf(*args, **kwargs):
         f = kwargs.get('file', sys.stdout)
         end = kwargs.get('end', '\n')
         f.write(b' '.join(args) + end)
 
     def sysstr(s):
         return s
 
 
 # Attempt to guide users to a modern pip - this means that 2.6 users
 # should have a chance of getting a 4.2 release, and when we ratchet
 # the version requirement forward again hopefully everyone will get
 # something that works for them.
 if sys.version_info < (2, 7, 4, 'final'):
     pip_message = (
         'This may be due to an out of date pip. '
         'Make sure you have pip >= 9.0.1.'
     )
     try:
         import pip
 
         pip_version = tuple([int(x) for x in pip.__version__.split('.')[:3]])
         if pip_version < (9, 0, 1):
             pip_message = (
                 'Your pip version is out of date, please install '
                 'pip >= 9.0.1. pip {} detected.'.format(pip.__version__)
             )
         else:
             # pip is new enough - it must be something else
             pip_message = ''
     except Exception:
         pass
     error = """
 Mercurial does not support Python older than 2.7.4.
 Python {py} detected.
 {pip}
 """.format(
         py=sys.version_info, pip=pip_message
     )
     printf(error, file=sys.stderr)
     sys.exit(1)
 
 import ssl
 
 try:
     ssl.SSLContext
 except AttributeError:
     error = """
 The `ssl` module does not have the `SSLContext` class. This indicates an old
 Python version which does not support modern security features (which were
 added to Python 2.7 as part of "PEP 466"). Please make sure you have installed
 at least Python 2.7.9 or a Python version with backports of these security
 features.
 """
     printf(error, file=sys.stderr)
     sys.exit(1)
 
 # ssl.HAS_TLSv1* are preferred to check support but they were added in Python
 # 3.7. Prior to CPython commit 6e8cda91d92da72800d891b2fc2073ecbc134d98
 # (backported to the 3.7 branch), ssl.PROTOCOL_TLSv1_1 / ssl.PROTOCOL_TLSv1_2
 # were defined only if compiled against a OpenSSL version with TLS 1.1 / 1.2
 # support. At the mentioned commit, they were unconditionally defined.
 _notset = object()
 has_tlsv1_1 = getattr(ssl, 'HAS_TLSv1_1', _notset)
 if has_tlsv1_1 is _notset:
     has_tlsv1_1 = getattr(ssl, 'PROTOCOL_TLSv1_1', _notset) is not _notset
 has_tlsv1_2 = getattr(ssl, 'HAS_TLSv1_2', _notset)
 if has_tlsv1_2 is _notset:
     has_tlsv1_2 = getattr(ssl, 'PROTOCOL_TLSv1_2', _notset) is not _notset
 if not (has_tlsv1_1 or has_tlsv1_2):
     error = """
 The `ssl` module does not advertise support for TLS 1.1 or TLS 1.2.
 Please make sure that your Python installation was compiled against an OpenSSL
 version enabling these features (likely this requires the OpenSSL version to
 be at least 1.0.1).
 """
     printf(error, file=sys.stderr)
     sys.exit(1)
 
 if sys.version_info[0] >= 3:
     DYLIB_SUFFIX = sysconfig.get_config_vars()['EXT_SUFFIX']
 else:
     # deprecated in Python 3
     DYLIB_SUFFIX = sysconfig.get_config_vars()['SO']
 
 # Solaris Python packaging brain damage
 try:
     import hashlib
 
     sha = hashlib.sha1()
 except ImportError:
     try:
         import sha
 
         sha.sha  # silence unused import warning
     except ImportError:
         raise SystemExit(
             "Couldn't import standard hashlib (incomplete Python install)."
         )
 
 try:
     import zlib
 
     zlib.compressobj  # silence unused import warning
 except ImportError:
     raise SystemExit(
         "Couldn't import standard zlib (incomplete Python install)."
     )
 
 # The base IronPython distribution (as of 2.7.1) doesn't support bz2
 isironpython = False
 try:
     isironpython = (
         platform.python_implementation().lower().find("ironpython") != -1
     )
 except AttributeError:
     pass
 
 if isironpython:
     sys.stderr.write("warning: IronPython detected (no bz2 support)\n")
 else:
     try:
         import bz2
 
         bz2.BZ2Compressor  # silence unused import warning
     except ImportError:
         raise SystemExit(
             "Couldn't import standard bz2 (incomplete Python install)."
         )
 
 ispypy = "PyPy" in sys.version
 
 import ctypes
 import errno
 import stat, subprocess, time
 import re
 import shutil
 import tempfile
 from distutils import log
 
 # We have issues with setuptools on some platforms and builders. Until
 # those are resolved, setuptools is opt-in except for platforms where
 # we don't have issues.
 issetuptools = os.name == 'nt' or 'FORCE_SETUPTOOLS' in os.environ
 if issetuptools:
     from setuptools import setup
 else:
     from distutils.core import setup
 from distutils.ccompiler import new_compiler
 from distutils.core import Command, Extension
 from distutils.dist import Distribution
 from distutils.command.build import build
 from distutils.command.build_ext import build_ext
 from distutils.command.build_py import build_py
 from distutils.command.build_scripts import build_scripts
 from distutils.command.install import install
 from distutils.command.install_lib import install_lib
 from distutils.command.install_scripts import install_scripts
 from distutils.spawn import spawn, find_executable
 from distutils import file_util
 from distutils.errors import (
     CCompilerError,
     DistutilsError,
     DistutilsExecError,
 )
 from distutils.sysconfig import get_python_inc, get_config_var
 from distutils.version import StrictVersion
 
 # Explain to distutils.StrictVersion how our release candidates are versionned
 StrictVersion.version_re = re.compile(r'^(\d+)\.(\d+)(\.(\d+))?-?(rc(\d+))?$')
 
 
 def write_if_changed(path, content):
     """Write content to a file iff the content hasn't changed."""
     if os.path.exists(path):
         with open(path, 'rb') as fh:
             current = fh.read()
     else:
         current = b''
 
     if current != content:
         with open(path, 'wb') as fh:
             fh.write(content)
 
 
 scripts = ['hg']
 if os.name == 'nt':
     # We remove hg.bat if we are able to build hg.exe.
     scripts.append('contrib/win32/hg.bat')
 
 
 def cancompile(cc, code):
     tmpdir = tempfile.mkdtemp(prefix='hg-install-')
     devnull = oldstderr = None
     try:
         fname = os.path.join(tmpdir, 'testcomp.c')
         f = open(fname, 'w')
         f.write(code)
         f.close()
         # Redirect stderr to /dev/null to hide any error messages
         # from the compiler.
         # This will have to be changed if we ever have to check
         # for a function on Windows.
         devnull = open('/dev/null', 'w')
         oldstderr = os.dup(sys.stderr.fileno())
         os.dup2(devnull.fileno(), sys.stderr.fileno())
         objects = cc.compile([fname], output_dir=tmpdir)
         cc.link_executable(objects, os.path.join(tmpdir, "a.out"))
         return True
     except Exception:
         return False
     finally:
         if oldstderr is not None:
             os.dup2(oldstderr, sys.stderr.fileno())
         if devnull is not None:
             devnull.close()
         shutil.rmtree(tmpdir)
 
 
 # simplified version of distutils.ccompiler.CCompiler.has_function
 # that actually removes its temporary files.
 def hasfunction(cc, funcname):
     code = 'int main(void) { %s(); }\n' % funcname
     return cancompile(cc, code)
 
 
 def hasheader(cc, headername):
     code = '#include <%s>\nint main(void) { return 0; }\n' % headername
     return cancompile(cc, code)
 
 
 # py2exe needs to be installed to work
 try:
     import py2exe
 
     py2exe.Distribution  # silence unused import warning
     py2exeloaded = True
     # import py2exe's patched Distribution class
     from distutils.core import Distribution
 except ImportError:
     py2exeloaded = False
 
 
 def runcmd(cmd, env, cwd=None):
     p = subprocess.Popen(
         cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, env=env, cwd=cwd
     )
     out, err = p.communicate()
     return p.returncode, out, err
 
 
 class hgcommand(object):
     def __init__(self, cmd, env):
         self.cmd = cmd
         self.env = env
 
     def run(self, args):
         cmd = self.cmd + args
         returncode, out, err = runcmd(cmd, self.env)
         err = filterhgerr(err)
         if err or returncode != 0:
             printf("stderr from '%s':" % (' '.join(cmd)), file=sys.stderr)
             printf(err, file=sys.stderr)
             return b''
         return out
 
 
 def filterhgerr(err):
     # If root is executing setup.py, but the repository is owned by
     # another user (as in "sudo python setup.py install") we will get
     # trust warnings since the .hg/hgrc file is untrusted. That is
     # fine, we don't want to load it anyway.  Python may warn about
     # a missing __init__.py in mercurial/locale, we also ignore that.
     err = [
         e
         for e in err.splitlines()
         if (
             not e.startswith(b'not trusting file')
             and not e.startswith(b'warning: Not importing')
             and not e.startswith(b'obsolete feature not enabled')
             and not e.startswith(b'*** failed to import extension')
             and not e.startswith(b'devel-warn:')
             and not (
                 e.startswith(b'(third party extension')
                 and e.endswith(b'or newer of Mercurial; disabling)')
             )
         )
     ]
     return b'\n'.join(b'  ' + e for e in err)
 
 
 def findhg():
     """Try to figure out how we should invoke hg for examining the local
     repository contents.
 
     Returns an hgcommand object."""
     # By default, prefer the "hg" command in the user's path.  This was
     # presumably the hg command that the user used to create this repository.
     #
     # This repository may require extensions or other settings that would not
     # be enabled by running the hg script directly from this local repository.
     hgenv = os.environ.copy()
     # Use HGPLAIN to disable hgrc settings that would change output formatting,
     # and disable localization for the same reasons.
     hgenv['HGPLAIN'] = '1'
     hgenv['LANGUAGE'] = 'C'
     hgcmd = ['hg']
     # Run a simple "hg log" command just to see if using hg from the user's
     # path works and can successfully interact with this repository.  Windows
     # gives precedence to hg.exe in the current directory, so fall back to the
     # python invocation of local hg, where pythonXY.dll can always be found.
     check_cmd = ['log', '-r.', '-Ttest']
     if os.name != 'nt' or not os.path.exists("hg.exe"):
         try:
             retcode, out, err = runcmd(hgcmd + check_cmd, hgenv)
         except EnvironmentError:
             retcode = -1
         if retcode == 0 and not filterhgerr(err):
             return hgcommand(hgcmd, hgenv)
 
     # Fall back to trying the local hg installation.
     hgenv = localhgenv()
     hgcmd = [sys.executable, 'hg']
     try:
         retcode, out, err = runcmd(hgcmd + check_cmd, hgenv)
     except EnvironmentError:
         retcode = -1
     if retcode == 0 and not filterhgerr(err):
         return hgcommand(hgcmd, hgenv)
 
     raise SystemExit(
         'Unable to find a working hg binary to extract the '
         'version from the repository tags'
     )
 
 
 def localhgenv():
     """Get an environment dictionary to use for invoking or importing
     mercurial from the local repository."""
     # Execute hg out of this directory with a custom environment which takes
     # care to not use any hgrc files and do no localization.
     env = {
         'HGMODULEPOLICY': 'py',
         'HGRCPATH': '',
         'LANGUAGE': 'C',
         'PATH': '',
     }  # make pypi modules that use os.environ['PATH'] happy
     if 'LD_LIBRARY_PATH' in os.environ:
         env['LD_LIBRARY_PATH'] = os.environ['LD_LIBRARY_PATH']
     if 'SystemRoot' in os.environ:
         # SystemRoot is required by Windows to load various DLLs.  See:
         # https://bugs.python.org/issue13524#msg148850
         env['SystemRoot'] = os.environ['SystemRoot']
     return env
 
 
 version = ''
 
 if os.path.isdir('.hg'):
     hg = findhg()
     cmd = ['log', '-r', '.', '--template', '{tags}\n']
     numerictags = [t for t in sysstr(hg.run(cmd)).split() if t[0:1].isdigit()]
     hgid = sysstr(hg.run(['id', '-i'])).strip()
     if not hgid:
         # Bail out if hg is having problems interacting with this repository,
         # rather than falling through and producing a bogus version number.
         # Continuing with an invalid version number will break extensions
         # that define minimumhgversion.
         raise SystemExit('Unable to determine hg version from local repository')
     if numerictags:  # tag(s) found
         version = numerictags[-1]
         if hgid.endswith('+'):  # propagate the dirty status to the tag
             version += '+'
     else:  # no tag found
         ltagcmd = ['parents', '--template', '{latesttag}']
         ltag = sysstr(hg.run(ltagcmd))
         changessincecmd = ['log', '-T', 'x\n', '-r', "only(.,'%s')" % ltag]
         changessince = len(hg.run(changessincecmd).splitlines())
         version = '%s+%s-%s' % (ltag, changessince, hgid)
     if version.endswith('+'):
         version += time.strftime('%Y%m%d')
 elif os.path.exists('.hg_archival.txt'):
     kw = dict(
         [[t.strip() for t in l.split(':', 1)] for l in open('.hg_archival.txt')]
     )
     if 'tag' in kw:
         version = kw['tag']
     elif 'latesttag' in kw:
         if 'changessincelatesttag' in kw:
             version = '%(latesttag)s+%(changessincelatesttag)s-%(node).12s' % kw
         else:
             version = '%(latesttag)s+%(latesttagdistance)s-%(node).12s' % kw
     else:
         version = kw.get('node', '')[:12]
 
 if version:
     versionb = version
     if not isinstance(versionb, bytes):
         versionb = versionb.encode('ascii')
 
     write_if_changed(
         'mercurial/__version__.py',
         b''.join(
             [
                 b'# this file is autogenerated by setup.py\n'
                 b'version = b"%s"\n' % versionb,
             ]
         ),
     )
 
 try:
     oldpolicy = os.environ.get('HGMODULEPOLICY', None)
     os.environ['HGMODULEPOLICY'] = 'py'
     from mercurial import __version__
 
     version = __version__.version
 except ImportError:
     version = b'unknown'
 finally:
     if oldpolicy is None:
         del os.environ['HGMODULEPOLICY']
     else:
         os.environ['HGMODULEPOLICY'] = oldpolicy
 
 
 class hgbuild(build):
     # Insert hgbuildmo first so that files in mercurial/locale/ are found
     # when build_py is run next.
     sub_commands = [('build_mo', None)] + build.sub_commands
 
 
 class hgbuildmo(build):
 
     description = "build translations (.mo files)"
 
     def run(self):
         if not find_executable('msgfmt'):
             self.warn(
                 "could not find msgfmt executable, no translations "
                 "will be built"
             )
             return
 
         podir = 'i18n'
         if not os.path.isdir(podir):
             self.warn("could not find %s/ directory" % podir)
             return
 
         join = os.path.join
         for po in os.listdir(podir):
             if not po.endswith('.po'):
                 continue
             pofile = join(podir, po)
             modir = join('locale', po[:-3], 'LC_MESSAGES')
             mofile = join(modir, 'hg.mo')
             mobuildfile = join('mercurial', mofile)
             cmd = ['msgfmt', '-v', '-o', mobuildfile, pofile]
             if sys.platform != 'sunos5':
                 # msgfmt on Solaris does not know about -c
                 cmd.append('-c')
             self.mkpath(join('mercurial', modir))
             self.make_file([pofile], mobuildfile, spawn, (cmd,))
 
 
 class hgdist(Distribution):
     pure = False
     rust = False
     no_rust = False
     cffi = ispypy
 
     global_options = Distribution.global_options + [
         ('pure', None, "use pure (slow) Python code instead of C extensions"),
         ('rust', None, "use Rust extensions additionally to C extensions"),
         (
             'no-rust',
             None,
             "do not use Rust extensions additionally to C extensions",
         ),
     ]
 
     negative_opt = Distribution.negative_opt.copy()
     boolean_options = ['pure', 'rust', 'no-rust']
     negative_opt['no-rust'] = 'rust'
 
     def _set_command_options(self, command_obj, option_dict=None):
         # Not all distutils versions in the wild have boolean_options.
         # This should be cleaned up when we're Python 3 only.
         command_obj.boolean_options = (
             getattr(command_obj, 'boolean_options', []) + self.boolean_options
         )
         return Distribution._set_command_options(
             self, command_obj, option_dict=option_dict
         )
 
     def parse_command_line(self):
         ret = Distribution.parse_command_line(self)
         if not (self.rust or self.no_rust):
             hgrustext = os.environ.get('HGWITHRUSTEXT')
             # TODO record it for proper rebuild upon changes
             # (see mercurial/__modulepolicy__.py)
             if hgrustext != 'cpython' and hgrustext is not None:
                 if hgrustext:
                     msg = 'unkown HGWITHRUSTEXT value: %s' % hgrustext
                     printf(msg, file=sys.stderr)
                 hgrustext = None
             self.rust = hgrustext is not None
             self.no_rust = not self.rust
         return ret
 
     def has_ext_modules(self):
         # self.ext_modules is emptied in hgbuildpy.finalize_options which is
         # too late for some cases
         return not self.pure and Distribution.has_ext_modules(self)
 
 
 # This is ugly as a one-liner. So use a variable.
 buildextnegops = dict(getattr(build_ext, 'negative_options', {}))
 buildextnegops['no-zstd'] = 'zstd'
 buildextnegops['no-rust'] = 'rust'
 
 
 class hgbuildext(build_ext):
     user_options = build_ext.user_options + [
         ('zstd', None, 'compile zstd bindings [default]'),
         ('no-zstd', None, 'do not compile zstd bindings'),
         (
             'rust',
             None,
             'compile Rust extensions if they are in use '
             '(requires Cargo) [default]',
         ),
         ('no-rust', None, 'do not compile Rust extensions'),
     ]
 
     boolean_options = build_ext.boolean_options + ['zstd', 'rust']
     negative_opt = buildextnegops
 
     def initialize_options(self):
         self.zstd = True
         self.rust = True
 
         return build_ext.initialize_options(self)
 
     def finalize_options(self):
         # Unless overridden by the end user, build extensions in parallel.
         # Only influences behavior on Python 3.5+.
         if getattr(self, 'parallel', None) is None:
             self.parallel = True
 
         return build_ext.finalize_options(self)
 
     def build_extensions(self):
         ruststandalones = [
             e for e in self.extensions if isinstance(e, RustStandaloneExtension)
         ]
         self.extensions = [
             e for e in self.extensions if e not in ruststandalones
         ]
         # Filter out zstd if disabled via argument.
         if not self.zstd:
             self.extensions = [
                 e for e in self.extensions if e.name != 'mercurial.zstd'
             ]
 
         # Build Rust standalon extensions if it'll be used
         # and its build is not explictely disabled (for external build
         # as Linux distributions would do)
         if self.distribution.rust and self.rust:
             for rustext in ruststandalones:
                 rustext.build('' if self.inplace else self.build_lib)
 
         return build_ext.build_extensions(self)
 
     def build_extension(self, ext):
         if (
             self.distribution.rust
             and self.rust
             and isinstance(ext, RustExtension)
         ):
             ext.rustbuild()
         try:
             build_ext.build_extension(self, ext)
         except CCompilerError:
             if not getattr(ext, 'optional', False):
                 raise
             log.warn(
                 "Failed to build optional extension '%s' (skipping)", ext.name
             )
 
 
 class hgbuildscripts(build_scripts):
     def run(self):
         if os.name != 'nt' or self.distribution.pure:
             return build_scripts.run(self)
 
         exebuilt = False
         try:
             self.run_command('build_hgexe')
             exebuilt = True
         except (DistutilsError, CCompilerError):
             log.warn('failed to build optional hg.exe')
 
         if exebuilt:
             # Copying hg.exe to the scripts build directory ensures it is
             # installed by the install_scripts command.
             hgexecommand = self.get_finalized_command('build_hgexe')
             dest = os.path.join(self.build_dir, 'hg.exe')
             self.mkpath(self.build_dir)
             self.copy_file(hgexecommand.hgexepath, dest)
 
             # Remove hg.bat because it is redundant with hg.exe.
             self.scripts.remove('contrib/win32/hg.bat')
 
         return build_scripts.run(self)
 
 
 class hgbuildpy(build_py):
     def finalize_options(self):
         build_py.finalize_options(self)
 
         if self.distribution.pure:
             self.distribution.ext_modules = []
         elif self.distribution.cffi:
             from mercurial.cffi import (
                 bdiffbuild,
                 mpatchbuild,
             )
 
             exts = [
                 mpatchbuild.ffi.distutils_extension(),
                 bdiffbuild.ffi.distutils_extension(),
             ]
             # cffi modules go here
             if sys.platform == 'darwin':
                 from mercurial.cffi import osutilbuild
 
                 exts.append(osutilbuild.ffi.distutils_extension())
             self.distribution.ext_modules = exts
         else:
             h = os.path.join(get_python_inc(), 'Python.h')
             if not os.path.exists(h):
                 raise SystemExit(
                     'Python headers are required to build '
                     'Mercurial but weren\'t found in %s' % h
                 )
 
     def run(self):
         basepath = os.path.join(self.build_lib, 'mercurial')
         self.mkpath(basepath)
 
         rust = self.distribution.rust
         if self.distribution.pure:
             modulepolicy = 'py'
         elif self.build_lib == '.':
             # in-place build should run without rebuilding and Rust extensions
             modulepolicy = 'rust+c-allow' if rust else 'allow'
         else:
             modulepolicy = 'rust+c' if rust else 'c'
 
         content = b''.join(
             [
                 b'# this file is autogenerated by setup.py\n',
                 b'modulepolicy = b"%s"\n' % modulepolicy.encode('ascii'),
             ]
         )
         write_if_changed(os.path.join(basepath, '__modulepolicy__.py'), content)
 
         build_py.run(self)
 
 
 class buildhgextindex(Command):
     description = 'generate prebuilt index of hgext (for frozen package)'
     user_options = []
     _indexfilename = 'hgext/__index__.py'
 
     def initialize_options(self):
         pass
 
     def finalize_options(self):
         pass
 
     def run(self):
         if os.path.exists(self._indexfilename):
             with open(self._indexfilename, 'w') as f:
                 f.write('# empty\n')
 
         # here no extension enabled, disabled() lists up everything
         code = (
             'import pprint; from mercurial import extensions; '
             'ext = extensions.disabled();'
             'ext.pop("__index__", None);'
             'pprint.pprint(ext)'
         )
         returncode, out, err = runcmd(
             [sys.executable, '-c', code], localhgenv()
         )
         if err or returncode != 0:
             raise DistutilsExecError(err)
 
         with open(self._indexfilename, 'wb') as f:
             f.write(b'# this file is autogenerated by setup.py\n')
             f.write(b'docs = ')
             f.write(out)
 
 
 class buildhgexe(build_ext):
     description = 'compile hg.exe from mercurial/exewrapper.c'
     user_options = build_ext.user_options + [
         (
             'long-paths-support',
             None,
             'enable support for long paths on '
             'Windows (off by default and '
             'experimental)',
         ),
     ]
 
     LONG_PATHS_MANIFEST = """
     <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
     <assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">
         <application>
             <windowsSettings
             xmlns:ws2="http://schemas.microsoft.com/SMI/2016/WindowsSettings">
                 <ws2:longPathAware>true</ws2:longPathAware>
             </windowsSettings>
         </application>
     </assembly>"""
 
     def initialize_options(self):
         build_ext.initialize_options(self)
         self.long_paths_support = False
 
     def build_extensions(self):
         if os.name != 'nt':
             return
         if isinstance(self.compiler, HackedMingw32CCompiler):
             self.compiler.compiler_so = self.compiler.compiler  # no -mdll
             self.compiler.dll_libraries = []  # no -lmsrvc90
 
         pythonlib = None
 
         dir = os.path.dirname(self.get_ext_fullpath('dummy'))
         self.hgtarget = os.path.join(dir, 'hg')
 
         if getattr(sys, 'dllhandle', None):
             # Different Python installs can have different Python library
             # names. e.g. the official CPython distribution uses pythonXY.dll
             # and MinGW uses libpythonX.Y.dll.
             _kernel32 = ctypes.windll.kernel32
             _kernel32.GetModuleFileNameA.argtypes = [
                 ctypes.c_void_p,
                 ctypes.c_void_p,
                 ctypes.c_ulong,
             ]
             _kernel32.GetModuleFileNameA.restype = ctypes.c_ulong
             size = 1000
             buf = ctypes.create_string_buffer(size + 1)
             filelen = _kernel32.GetModuleFileNameA(
                 sys.dllhandle, ctypes.byref(buf), size
             )
 
             if filelen > 0 and filelen != size:
                 dllbasename = os.path.basename(buf.value)
                 if not dllbasename.lower().endswith(b'.dll'):
                     raise SystemExit(
                         'Python DLL does not end with .dll: %s' % dllbasename
                     )
                 pythonlib = dllbasename[:-4]
 
                 # Copy the pythonXY.dll next to the binary so that it runs
                 # without tampering with PATH.
                 fsdecode = lambda x: x
                 if sys.version_info[0] >= 3:
                     fsdecode = os.fsdecode
                 dest = os.path.join(
                     os.path.dirname(self.hgtarget),
                     fsdecode(dllbasename),
                 )
 
                 if not os.path.exists(dest):
                     shutil.copy(buf.value, dest)
 
         if not pythonlib:
             log.warn(
                 'could not determine Python DLL filename; assuming pythonXY'
             )
 
             hv = sys.hexversion
             pythonlib = b'python%d%d' % (hv >> 24, (hv >> 16) & 0xFF)
 
         log.info('using %s as Python library name' % pythonlib)
         with open('mercurial/hgpythonlib.h', 'wb') as f:
             f.write(b'/* this file is autogenerated by setup.py */\n')
             f.write(b'#define HGPYTHONLIB "%s"\n' % pythonlib)
 
         macros = None
         if sys.version_info[0] >= 3:
             macros = [('_UNICODE', None), ('UNICODE', None)]
 
         objects = self.compiler.compile(
             ['mercurial/exewrapper.c'],
             output_dir=self.build_temp,
             macros=macros,
         )
         self.compiler.link_executable(
             objects, self.hgtarget, libraries=[], output_dir=self.build_temp
         )
         if self.long_paths_support:
             self.addlongpathsmanifest()
 
     def addlongpathsmanifest(self):
         r"""Add manifest pieces so that hg.exe understands long paths
 
         This is an EXPERIMENTAL feature, use with care.
         To enable long paths support, one needs to do two things:
         - build Mercurial with --long-paths-support option
         - change HKLM\SYSTEM\CurrentControlSet\Control\FileSystem\
                  LongPathsEnabled to have value 1.
 
         Please ignore 'warning 81010002: Unrecognized Element "longPathAware"';
         it happens because Mercurial uses mt.exe circa 2008, which is not
         yet aware of long paths support in the manifest (I think so at least).
         This does not stop mt.exe from embedding/merging the XML properly.
 
         Why resource #1 should be used for .exe manifests? I don't know and
         wasn't able to find an explanation for mortals. But it seems to work.
         """
         exefname = self.compiler.executable_filename(self.hgtarget)
         fdauto, manfname = tempfile.mkstemp(suffix='.hg.exe.manifest')
         os.close(fdauto)
         with open(manfname, 'w') as f:
             f.write(self.LONG_PATHS_MANIFEST)
         log.info("long paths manifest is written to '%s'" % manfname)
         inputresource = '-inputresource:%s;#1' % exefname
         outputresource = '-outputresource:%s;#1' % exefname
         log.info("running mt.exe to update hg.exe's manifest in-place")
         # supplying both -manifest and -inputresource to mt.exe makes
         # it merge the embedded and supplied manifests in the -outputresource
         self.spawn(
             [
                 'mt.exe',
                 '-nologo',
                 '-manifest',
                 manfname,
                 inputresource,
                 outputresource,
             ]
         )
         log.info("done updating hg.exe's manifest")
         os.remove(manfname)
 
     @property
     def hgexepath(self):
         dir = os.path.dirname(self.get_ext_fullpath('dummy'))
         return os.path.join(self.build_temp, dir, 'hg.exe')
 
 
 class hgbuilddoc(Command):
     description = 'build documentation'
     user_options = [
         ('man', None, 'generate man pages'),
         ('html', None, 'generate html pages'),
     ]
 
     def initialize_options(self):
         self.man = None
         self.html = None
 
     def finalize_options(self):
         # If --man or --html are set, only generate what we're told to.
         # Otherwise generate everything.
         have_subset = self.man is not None or self.html is not None
 
         if have_subset:
             self.man = True if self.man else False
             self.html = True if self.html else False
         else:
             self.man = True
             self.html = True
 
     def run(self):
         def normalizecrlf(p):
             with open(p, 'rb') as fh:
                 orig = fh.read()
 
             if b'\r\n' not in orig:
                 return
 
             log.info('normalizing %s to LF line endings' % p)
             with open(p, 'wb') as fh:
                 fh.write(orig.replace(b'\r\n', b'\n'))
 
         def gentxt(root):
             txt = 'doc/%s.txt' % root
             log.info('generating %s' % txt)
             res, out, err = runcmd(
                 [sys.executable, 'gendoc.py', root], os.environ, cwd='doc'
             )
             if res:
                 raise SystemExit(
                     'error running gendoc.py: %s'
                     % '\n'.join([sysstr(out), sysstr(err)])
                 )
 
             with open(txt, 'wb') as fh:
                 fh.write(out)
 
         def gengendoc(root):
             gendoc = 'doc/%s.gendoc.txt' % root
 
             log.info('generating %s' % gendoc)
             res, out, err = runcmd(
                 [sys.executable, 'gendoc.py', '%s.gendoc' % root],
                 os.environ,
                 cwd='doc',
             )
             if res:
                 raise SystemExit(
                     'error running gendoc: %s'
                     % '\n'.join([sysstr(out), sysstr(err)])
                 )
 
             with open(gendoc, 'wb') as fh:
                 fh.write(out)
 
         def genman(root):
             log.info('generating doc/%s' % root)
             res, out, err = runcmd(
                 [
                     sys.executable,
                     'runrst',
                     'hgmanpage',
                     '--halt',
                     'warning',
                     '--strip-elements-with-class',
                     'htmlonly',
                     '%s.txt' % root,
                     root,
                 ],
                 os.environ,
                 cwd='doc',
             )
             if res:
                 raise SystemExit(
                     'error running runrst: %s'
                     % '\n'.join([sysstr(out), sysstr(err)])
                 )
 
             normalizecrlf('doc/%s' % root)
 
         def genhtml(root):
             log.info('generating doc/%s.html' % root)
             res, out, err = runcmd(
                 [
                     sys.executable,
                     'runrst',
                     'html',
                     '--halt',
                     'warning',
                     '--link-stylesheet',
                     '--stylesheet-path',
                     'style.css',
                     '%s.txt' % root,
                     '%s.html' % root,
                 ],
                 os.environ,
                 cwd='doc',
             )
             if res:
                 raise SystemExit(
                     'error running runrst: %s'
                     % '\n'.join([sysstr(out), sysstr(err)])
                 )
 
             normalizecrlf('doc/%s.html' % root)
 
         # This logic is duplicated in doc/Makefile.
         sources = {
             f
             for f in os.listdir('mercurial/helptext')
             if re.search(r'[0-9]\.txt$', f)
         }
 
         # common.txt is a one-off.
         gentxt('common')
 
         for source in sorted(sources):
             assert source[-4:] == '.txt'
             root = source[:-4]
 
             gentxt(root)
             gengendoc(root)
 
             if self.man:
                 genman(root)
             if self.html:
                 genhtml(root)
 
 
 class hginstall(install):
 
     user_options = install.user_options + [
         (
             'old-and-unmanageable',
             None,
             'noop, present for eggless setuptools compat',
         ),
         (
             'single-version-externally-managed',
             None,
             'noop, present for eggless setuptools compat',
         ),
     ]
 
     # Also helps setuptools not be sad while we refuse to create eggs.
     single_version_externally_managed = True
 
     def get_sub_commands(self):
         # Screen out egg related commands to prevent egg generation.  But allow
         # mercurial.egg-info generation, since that is part of modern
         # packaging.
         excl = {'bdist_egg'}
         return filter(lambda x: x not in excl, install.get_sub_commands(self))
 
 
 class hginstalllib(install_lib):
     """
     This is a specialization of install_lib that replaces the copy_file used
     there so that it supports setting the mode of files after copying them,
     instead of just preserving the mode that the files originally had.  If your
     system has a umask of something like 027, preserving the permissions when
     copying will lead to a broken install.
 
     Note that just passing keep_permissions=False to copy_file would be
     insufficient, as it might still be applying a umask.
     """
 
     def run(self):
         realcopyfile = file_util.copy_file
 
         def copyfileandsetmode(*args, **kwargs):
             src, dst = args[0], args[1]
             dst, copied = realcopyfile(*args, **kwargs)
             if copied:
                 st = os.stat(src)
                 # Persist executable bit (apply it to group and other if user
                 # has it)
                 if st[stat.ST_MODE] & stat.S_IXUSR:
                     setmode = int('0755', 8)
                 else:
                     setmode = int('0644', 8)
                 m = stat.S_IMODE(st[stat.ST_MODE])
                 m = (m & ~int('0777', 8)) | setmode
                 os.chmod(dst, m)
 
         file_util.copy_file = copyfileandsetmode
         try:
             install_lib.run(self)
         finally:
             file_util.copy_file = realcopyfile
 
 
 class hginstallscripts(install_scripts):
     """
     This is a specialization of install_scripts that replaces the @LIBDIR@ with
     the configured directory for modules. If possible, the path is made relative
     to the directory for scripts.
     """
 
     def initialize_options(self):
         install_scripts.initialize_options(self)
 
         self.install_lib = None
 
     def finalize_options(self):
         install_scripts.finalize_options(self)
         self.set_undefined_options('install', ('install_lib', 'install_lib'))
 
     def run(self):
         install_scripts.run(self)
 
         # It only makes sense to replace @LIBDIR@ with the install path if
         # the install path is known. For wheels, the logic below calculates
         # the libdir to be "../..". This is because the internal layout of a
         # wheel archive looks like:
         #
         #   mercurial-3.6.1.data/scripts/hg
         #   mercurial/__init__.py
         #
         # When installing wheels, the subdirectories of the "<pkg>.data"
         # directory are translated to system local paths and files therein
         # are copied in place. The mercurial/* files are installed into the
         # site-packages directory. However, the site-packages directory
         # isn't known until wheel install time. This means we have no clue
         # at wheel generation time what the installed site-packages directory
         # will be. And, wheels don't appear to provide the ability to register
         # custom code to run during wheel installation. This all means that
         # we can't reliably set the libdir in wheels: the default behavior
         # of looking in sys.path must do.
 
         if (
             os.path.splitdrive(self.install_dir)[0]
             != os.path.splitdrive(self.install_lib)[0]
         ):
             # can't make relative paths from one drive to another, so use an
             # absolute path instead
             libdir = self.install_lib
         else:
             libdir = os.path.relpath(self.install_lib, self.install_dir)
 
         for outfile in self.outfiles:
             with open(outfile, 'rb') as fp:
                 data = fp.read()
 
             # skip binary files
             if b'\0' in data:
                 continue
 
             # During local installs, the shebang will be rewritten to the final
             # install path. During wheel packaging, the shebang has a special
             # value.
             if data.startswith(b'#!python'):
                 log.info(
                     'not rewriting @LIBDIR@ in %s because install path '
                     'not known' % outfile
                 )
                 continue
 
             data = data.replace(b'@LIBDIR@', libdir.encode(libdir_escape))
             with open(outfile, 'wb') as fp:
                 fp.write(data)
 
 
 # virtualenv installs custom distutils/__init__.py and
 # distutils/distutils.cfg files which essentially proxy back to the
 # "real" distutils in the main Python install. The presence of this
 # directory causes py2exe to pick up the "hacked" distutils package
 # from the virtualenv and "import distutils" will fail from the py2exe
 # build because the "real" distutils files can't be located.
 #
 # We work around this by monkeypatching the py2exe code finding Python
 # modules to replace the found virtualenv distutils modules with the
 # original versions via filesystem scanning. This is a bit hacky. But
 # it allows us to use virtualenvs for py2exe packaging, which is more
 # deterministic and reproducible.
 #
 # It's worth noting that the common StackOverflow suggestions for this
 # problem involve copying the original distutils files into the
 # virtualenv or into the staging directory after setup() is invoked.
 # The former is very brittle and can easily break setup(). Our hacking
 # of the found modules routine has a similar result as copying the files
 # manually. But it makes fewer assumptions about how py2exe works and
 # is less brittle.
 
 # This only catches virtualenvs made with virtualenv (as opposed to
 # venv, which is likely what Python 3 uses).
 py2exehacked = py2exeloaded and getattr(sys, 'real_prefix', None) is not None
 
 if py2exehacked:
     from distutils.command.py2exe import py2exe as buildpy2exe
     from py2exe.mf import Module as py2exemodule
 
     class hgbuildpy2exe(buildpy2exe):
         def find_needed_modules(self, mf, files, modules):
             res = buildpy2exe.find_needed_modules(self, mf, files, modules)
 
             # Replace virtualenv's distutils modules with the real ones.
             modules = {}
             for k, v in res.modules.items():
                 if k != 'distutils' and not k.startswith('distutils.'):
                     modules[k] = v
 
             res.modules = modules
 
             import opcode
 
             distutilsreal = os.path.join(
                 os.path.dirname(opcode.__file__), 'distutils'
             )
 
             for root, dirs, files in os.walk(distutilsreal):
                 for f in sorted(files):
                     if not f.endswith('.py'):
                         continue
 
                     full = os.path.join(root, f)
 
                     parents = ['distutils']
 
                     if root != distutilsreal:
                         rel = os.path.relpath(root, distutilsreal)
                         parents.extend(p for p in rel.split(os.sep))
 
                     modname = '%s.%s' % ('.'.join(parents), f[:-3])
 
                     if modname.startswith('distutils.tests.'):
                         continue
 
                     if modname.endswith('.__init__'):
                         modname = modname[: -len('.__init__')]
                         path = os.path.dirname(full)
                     else:
                         path = None
 
                     res.modules[modname] = py2exemodule(
                         modname, full, path=path
                     )
 
             if 'distutils' not in res.modules:
                 raise SystemExit('could not find distutils modules')
 
             return res
 
 
 cmdclass = {
     'build': hgbuild,
     'build_doc': hgbuilddoc,
     'build_mo': hgbuildmo,
     'build_ext': hgbuildext,
     'build_py': hgbuildpy,
     'build_scripts': hgbuildscripts,
     'build_hgextindex': buildhgextindex,
     'install': hginstall,
     'install_lib': hginstalllib,
     'install_scripts': hginstallscripts,
     'build_hgexe': buildhgexe,
 }
 
 if py2exehacked:
     cmdclass['py2exe'] = hgbuildpy2exe
 
 packages = [
     'mercurial',
     'mercurial.cext',
     'mercurial.cffi',
     'mercurial.defaultrc',
     'mercurial.helptext',
     'mercurial.helptext.internals',
     'mercurial.hgweb',
     'mercurial.interfaces',
     'mercurial.pure',
     'mercurial.templates',
     'mercurial.thirdparty',
     'mercurial.thirdparty.attr',
     'mercurial.thirdparty.zope',
     'mercurial.thirdparty.zope.interface',
+    'mercurial.upgrade_utils',
     'mercurial.utils',
     'mercurial.revlogutils',
     'mercurial.testing',
     'hgext',
     'hgext.convert',
     'hgext.fsmonitor',
     'hgext.fastannotate',
     'hgext.fsmonitor.pywatchman',
     'hgext.git',
     'hgext.highlight',
     'hgext.hooklib',
     'hgext.infinitepush',
     'hgext.largefiles',
     'hgext.lfs',
     'hgext.narrow',
     'hgext.remotefilelog',
     'hgext.zeroconf',
     'hgext3rd',
     'hgdemandimport',
 ]
 
 for name in os.listdir(os.path.join('mercurial', 'templates')):
     if name != '__pycache__' and os.path.isdir(
         os.path.join('mercurial', 'templates', name)
     ):
         packages.append('mercurial.templates.%s' % name)
 
 if sys.version_info[0] == 2:
     packages.extend(
         [
             'mercurial.thirdparty.concurrent',
             'mercurial.thirdparty.concurrent.futures',
         ]
     )
 
 if 'HG_PY2EXE_EXTRA_INSTALL_PACKAGES' in os.environ:
     # py2exe can't cope with namespace packages very well, so we have to
     # install any hgext3rd.* extensions that we want in the final py2exe
     # image here. This is gross, but you gotta do what you gotta do.
     packages.extend(os.environ['HG_PY2EXE_EXTRA_INSTALL_PACKAGES'].split(' '))
 
 common_depends = [
     'mercurial/bitmanipulation.h',
     'mercurial/compat.h',
     'mercurial/cext/util.h',
 ]
 common_include_dirs = ['mercurial']
 
 common_cflags = []
 
 # MSVC 2008 still needs declarations at the top of the scope, but Python 3.9
 # makes declarations not at the top of a scope in the headers.
 if os.name != 'nt' and sys.version_info[1] < 9:
     common_cflags = ['-Werror=declaration-after-statement']
 
 osutil_cflags = []
 osutil_ldflags = []
 
 # platform specific macros
 for plat, func in [('bsd', 'setproctitle')]:
     if re.search(plat, sys.platform) and hasfunction(new_compiler(), func):
         osutil_cflags.append('-DHAVE_%s' % func.upper())
 
 for plat, macro, code in [
     (
         'bsd|darwin',
         'BSD_STATFS',
         '''
      #include <sys/param.h>
      #include <sys/mount.h>
      int main() { struct statfs s; return sizeof(s.f_fstypename); }
      ''',
     ),
     (
         'linux',
         'LINUX_STATFS',
         '''
      #include <linux/magic.h>
      #include <sys/vfs.h>
      int main() { struct statfs s; return sizeof(s.f_type); }
      ''',
     ),
 ]:
     if re.search(plat, sys.platform) and cancompile(new_compiler(), code):
         osutil_cflags.append('-DHAVE_%s' % macro)
 
 if sys.platform == 'darwin':
     osutil_ldflags += ['-framework', 'ApplicationServices']
 
 if sys.platform == 'sunos5':
     osutil_ldflags += ['-lsocket']
 
 xdiff_srcs = [
     'mercurial/thirdparty/xdiff/xdiffi.c',
     'mercurial/thirdparty/xdiff/xprepare.c',
     'mercurial/thirdparty/xdiff/xutils.c',
 ]
 
 xdiff_headers = [
     'mercurial/thirdparty/xdiff/xdiff.h',
     'mercurial/thirdparty/xdiff/xdiffi.h',
     'mercurial/thirdparty/xdiff/xinclude.h',
     'mercurial/thirdparty/xdiff/xmacros.h',
     'mercurial/thirdparty/xdiff/xprepare.h',
     'mercurial/thirdparty/xdiff/xtypes.h',
     'mercurial/thirdparty/xdiff/xutils.h',
 ]
 
 
 class RustCompilationError(CCompilerError):
     """Exception class for Rust compilation errors."""
 
 
 class RustExtension(Extension):
     """Base classes for concrete Rust Extension classes."""
 
     rusttargetdir = os.path.join('rust', 'target', 'release')
 
     def __init__(
         self, mpath, sources, rustlibname, subcrate, py3_features=None, **kw
     ):
         Extension.__init__(self, mpath, sources, **kw)
         srcdir = self.rustsrcdir = os.path.join('rust', subcrate)
         self.py3_features = py3_features
 
         # adding Rust source and control files to depends so that the extension
         # gets rebuilt if they've changed
         self.depends.append(os.path.join(srcdir, 'Cargo.toml'))
         cargo_lock = os.path.join(srcdir, 'Cargo.lock')
         if os.path.exists(cargo_lock):
             self.depends.append(cargo_lock)
         for dirpath, subdir, fnames in os.walk(os.path.join(srcdir, 'src')):
             self.depends.extend(
                 os.path.join(dirpath, fname)
                 for fname in fnames
                 if os.path.splitext(fname)[1] == '.rs'
             )
 
     @staticmethod
     def rustdylibsuffix():
         """Return the suffix for shared libraries produced by rustc.
 
         See also: https://doc.rust-lang.org/reference/linkage.html
         """
         if sys.platform == 'darwin':
             return '.dylib'
         elif os.name == 'nt':
             return '.dll'
         else:
             return '.so'
 
     def rustbuild(self):
         env = os.environ.copy()
         if 'HGTEST_RESTOREENV' in env:
             # Mercurial tests change HOME to a temporary directory,
             # but, if installed with rustup, the Rust toolchain needs
             # HOME to be correct (otherwise the 'no default toolchain'
             # error message is issued and the build fails).
             # This happens currently with test-hghave.t, which does
             # invoke this build.
 
             # Unix only fix (os.path.expanduser not really reliable if
             # HOME is shadowed like this)
             import pwd
 
             env['HOME'] = pwd.getpwuid(os.getuid()).pw_dir
 
         cargocmd = ['cargo', 'rustc', '--release']
 
         feature_flags = []
 
         if sys.version_info[0] == 3 and self.py3_features is not None:
             feature_flags.append(self.py3_features)
             cargocmd.append('--no-default-features')
 
         rust_features = env.get("HG_RUST_FEATURES")
         if rust_features:
             feature_flags.append(rust_features)
 
         cargocmd.extend(('--features', " ".join(feature_flags)))
 
         cargocmd.append('--')
         if sys.platform == 'darwin':
             cargocmd.extend(
                 ("-C", "link-arg=-undefined", "-C", "link-arg=dynamic_lookup")
             )
         try:
             subprocess.check_call(cargocmd, env=env, cwd=self.rustsrcdir)
         except OSError as exc:
             if exc.errno == errno.ENOENT:
                 raise RustCompilationError("Cargo not found")
             elif exc.errno == errno.EACCES:
                 raise RustCompilationError(
                     "Cargo found, but permisssion to execute it is denied"
                 )
             else:
                 raise
         except subprocess.CalledProcessError:
             raise RustCompilationError(
                 "Cargo failed. Working directory: %r, "
                 "command: %r, environment: %r"
                 % (self.rustsrcdir, cargocmd, env)
             )
 
 
 class RustStandaloneExtension(RustExtension):
     def __init__(self, pydottedname, rustcrate, dylibname, **kw):
         RustExtension.__init__(
             self, pydottedname, [], dylibname, rustcrate, **kw
         )
         self.dylibname = dylibname
 
     def build(self, target_dir):
         self.rustbuild()
         target = [target_dir]
         target.extend(self.name.split('.'))
         target[-1] += DYLIB_SUFFIX
         shutil.copy2(
             os.path.join(
                 self.rusttargetdir, self.dylibname + self.rustdylibsuffix()
             ),
             os.path.join(*target),
         )
 
 
 extmodules = [
     Extension(
         'mercurial.cext.base85',
         ['mercurial/cext/base85.c'],
         include_dirs=common_include_dirs,
         extra_compile_args=common_cflags,
         depends=common_depends,
     ),
     Extension(
         'mercurial.cext.bdiff',
         ['mercurial/bdiff.c', 'mercurial/cext/bdiff.c'] + xdiff_srcs,
         include_dirs=common_include_dirs,
         extra_compile_args=common_cflags,
         depends=common_depends + ['mercurial/bdiff.h'] + xdiff_headers,
     ),
     Extension(
         'mercurial.cext.mpatch',
         ['mercurial/mpatch.c', 'mercurial/cext/mpatch.c'],
         include_dirs=common_include_dirs,
         extra_compile_args=common_cflags,
         depends=common_depends,
     ),
     Extension(
         'mercurial.cext.parsers',
         [
             'mercurial/cext/charencode.c',
             'mercurial/cext/dirs.c',
             'mercurial/cext/manifest.c',
             'mercurial/cext/parsers.c',
             'mercurial/cext/pathencode.c',
             'mercurial/cext/revlog.c',
         ],
         include_dirs=common_include_dirs,
         extra_compile_args=common_cflags,
         depends=common_depends
         + [
             'mercurial/cext/charencode.h',
             'mercurial/cext/revlog.h',
         ],
     ),
     Extension(
         'mercurial.cext.osutil',
         ['mercurial/cext/osutil.c'],
         include_dirs=common_include_dirs,
         extra_compile_args=common_cflags + osutil_cflags,
         extra_link_args=osutil_ldflags,
         depends=common_depends,
     ),
     Extension(
         'mercurial.thirdparty.zope.interface._zope_interface_coptimizations',
         [
             'mercurial/thirdparty/zope/interface/_zope_interface_coptimizations.c',
         ],
         extra_compile_args=common_cflags,
     ),
     Extension(
         'mercurial.thirdparty.sha1dc',
         [
             'mercurial/thirdparty/sha1dc/cext.c',
             'mercurial/thirdparty/sha1dc/lib/sha1.c',
             'mercurial/thirdparty/sha1dc/lib/ubc_check.c',
         ],
         extra_compile_args=common_cflags,
     ),
     Extension(
         'hgext.fsmonitor.pywatchman.bser',
         ['hgext/fsmonitor/pywatchman/bser.c'],
         extra_compile_args=common_cflags,
     ),
     RustStandaloneExtension(
         'mercurial.rustext', 'hg-cpython', 'librusthg', py3_features='python3'
     ),
 ]
 
 
 sys.path.insert(0, 'contrib/python-zstandard')
 import setup_zstd
 
 zstd = setup_zstd.get_c_extension(
     name='mercurial.zstd', root=os.path.abspath(os.path.dirname(__file__))
 )
 zstd.extra_compile_args += common_cflags
 extmodules.append(zstd)
 
 try:
     from distutils import cygwinccompiler
 
     # the -mno-cygwin option has been deprecated for years
     mingw32compilerclass = cygwinccompiler.Mingw32CCompiler
 
     class HackedMingw32CCompiler(cygwinccompiler.Mingw32CCompiler):
         def __init__(self, *args, **kwargs):
             mingw32compilerclass.__init__(self, *args, **kwargs)
             for i in 'compiler compiler_so linker_exe linker_so'.split():
                 try:
                     getattr(self, i).remove('-mno-cygwin')
                 except ValueError:
                     pass
 
     cygwinccompiler.Mingw32CCompiler = HackedMingw32CCompiler
 except ImportError:
     # the cygwinccompiler package is not available on some Python
     # distributions like the ones from the optware project for Synology
     # DiskStation boxes
     class HackedMingw32CCompiler(object):
         pass
 
 
 if os.name == 'nt':
     # Allow compiler/linker flags to be added to Visual Studio builds.  Passing
     # extra_link_args to distutils.extensions.Extension() doesn't have any
     # effect.
     from distutils import msvccompiler
 
     msvccompilerclass = msvccompiler.MSVCCompiler
 
     class HackedMSVCCompiler(msvccompiler.MSVCCompiler):
         def initialize(self):
             msvccompilerclass.initialize(self)
             # "warning LNK4197: export 'func' specified multiple times"
             self.ldflags_shared.append('/ignore:4197')
             self.ldflags_shared_debug.append('/ignore:4197')
 
     msvccompiler.MSVCCompiler = HackedMSVCCompiler
 
 packagedata = {
     'mercurial': [
         'locale/*/LC_MESSAGES/hg.mo',
         'dummycert.pem',
     ],
     'mercurial.defaultrc': [
         '*.rc',
     ],
     'mercurial.helptext': [
         '*.txt',
     ],
     'mercurial.helptext.internals': [
         '*.txt',
     ],
 }
 
 
 def ordinarypath(p):
     return p and p[0] != '.' and p[-1] != '~'
 
 
 for root in ('templates',):
     for curdir, dirs, files in os.walk(os.path.join('mercurial', root)):
         packagename = curdir.replace(os.sep, '.')
         packagedata[packagename] = list(filter(ordinarypath, files))
 
 datafiles = []
 
 # distutils expects version to be str/unicode. Converting it to
 # unicode on Python 2 still works because it won't contain any
 # non-ascii bytes and will be implicitly converted back to bytes
 # when operated on.
 assert isinstance(version, bytes)
 setupversion = version.decode('ascii')
 
 extra = {}
 
 py2exepackages = [
     'hgdemandimport',
     'hgext3rd',
     'hgext',
     'email',
     # implicitly imported per module policy
     # (cffi wouldn't be used as a frozen exe)
     'mercurial.cext',
     #'mercurial.cffi',
     'mercurial.pure',
 ]
 
 py2exeexcludes = []
 py2exedllexcludes = ['crypt32.dll']
 
 if issetuptools:
     extra['python_requires'] = supportedpy
 
 if py2exeloaded:
     extra['console'] = [
         {
             'script': 'hg',
             'copyright': 'Copyright (C) 2005-2020 Matt Mackall and others',
             'product_version': version,
         }
     ]
     # Sub command of 'build' because 'py2exe' does not handle sub_commands.
     # Need to override hgbuild because it has a private copy of
     # build.sub_commands.
     hgbuild.sub_commands.insert(0, ('build_hgextindex', None))
     # put dlls in sub directory so that they won't pollute PATH
     extra['zipfile'] = 'lib/library.zip'
 
     # We allow some configuration to be supplemented via environment
     # variables. This is better than setup.cfg files because it allows
     # supplementing configs instead of replacing them.
     extrapackages = os.environ.get('HG_PY2EXE_EXTRA_PACKAGES')
     if extrapackages:
         py2exepackages.extend(extrapackages.split(' '))
 
     excludes = os.environ.get('HG_PY2EXE_EXTRA_EXCLUDES')
     if excludes:
         py2exeexcludes.extend(excludes.split(' '))
 
     dllexcludes = os.environ.get('HG_PY2EXE_EXTRA_DLL_EXCLUDES')
     if dllexcludes:
         py2exedllexcludes.extend(dllexcludes.split(' '))
 
 if os.environ.get('PYOXIDIZER'):
     hgbuild.sub_commands.insert(0, ('build_hgextindex', None))
 
 if os.name == 'nt':
     # Windows binary file versions for exe/dll files must have the
     # form W.X.Y.Z, where W,X,Y,Z are numbers in the range 0..65535
     setupversion = setupversion.split(r'+', 1)[0]
 
 if sys.platform == 'darwin' and os.path.exists('/usr/bin/xcodebuild'):
     version = runcmd(['/usr/bin/xcodebuild', '-version'], {})[1].splitlines()
     if version:
         version = version[0]
         if sys.version_info[0] == 3:
             version = version.decode('utf-8')
         xcode4 = version.startswith('Xcode') and StrictVersion(
             version.split()[1]
         ) >= StrictVersion('4.0')
         xcode51 = re.match(r'^Xcode\s+5\.1', version) is not None
     else:
         # xcodebuild returns empty on OS X Lion with XCode 4.3 not
         # installed, but instead with only command-line tools. Assume
         # that only happens on >= Lion, thus no PPC support.
         xcode4 = True
         xcode51 = False
 
     # XCode 4.0 dropped support for ppc architecture, which is hardcoded in
     # distutils.sysconfig
     if xcode4:
         os.environ['ARCHFLAGS'] = ''
 
     # XCode 5.1 changes clang such that it now fails to compile if the
     # -mno-fused-madd flag is passed, but the version of Python shipped with
     # OS X 10.9 Mavericks includes this flag. This causes problems in all
     # C extension modules, and a bug has been filed upstream at
     # http://bugs.python.org/issue21244. We also need to patch this here
     # so Mercurial can continue to compile in the meantime.
     if xcode51:
         cflags = get_config_var('CFLAGS')
         if cflags and re.search(r'-mno-fused-madd\b', cflags) is not None:
             os.environ['CFLAGS'] = (
                 os.environ.get('CFLAGS', '') + ' -Qunused-arguments'
             )
 
 setup(
     name='mercurial',
     version=setupversion,
     author='Matt Mackall and many others',
     author_email='[e-mail]',
     url='https://mercurial-scm.org/',
     download_url='https://mercurial-scm.org/release/',
     description=(
         'Fast scalable distributed SCM (revision control, version '
         'control) system'
     ),
     long_description=(
         'Mercurial is a distributed SCM tool written in Python.'
         ' It is used by a number of large projects that require'
         ' fast, reliable distributed revision control, such as '
         'Mozilla.'
     ),
     license='GNU GPLv2 or any later version',
     classifiers=[
         'Development Status :: 6 - Mature',
         'Environment :: Console',
         'Intended Audience :: Developers',
         'Intended Audience :: System Administrators',
         'License :: OSI Approved :: GNU General Public License (GPL)',
         'Natural Language :: Danish',
         'Natural Language :: English',
         'Natural Language :: German',
         'Natural Language :: Italian',
         'Natural Language :: Japanese',
         'Natural Language :: Portuguese (Brazilian)',
         'Operating System :: Microsoft :: Windows',
         'Operating System :: OS Independent',
         'Operating System :: POSIX',
         'Programming Language :: C',
         'Programming Language :: Python',
         'Topic :: Software Development :: Version Control',
     ],
     scripts=scripts,
     packages=packages,
     ext_modules=extmodules,
     data_files=datafiles,
     package_data=packagedata,
     cmdclass=cmdclass,
     distclass=hgdist,
     options={
         'py2exe': {
             'bundle_files': 3,
             'dll_excludes': py2exedllexcludes,
             'excludes': py2exeexcludes,
             'packages': py2exepackages,
         },
         'bdist_mpkg': {
             'zipdist': False,
             'license': 'COPYING',
             'readme': 'contrib/packaging/macosx/Readme.html',
             'welcome': 'contrib/packaging/macosx/Welcome.html',
         },
     },
     **extra
 )

tests/testlib/ext-sidedata.py

@@ -1,83 +1,84 b''
 # ext-sidedata.py - small extension to test the sidedata logic
 #
 # Copyright 2019 Pierre-Yves David <[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 hashlib
 import struct
 
 from mercurial import (
     extensions,
     node,
     requirements,
     revlog,
-    upgrade,
 )
 
+from mercurial.upgrade_utils import engine as upgrade_engine
+
 from mercurial.revlogutils import sidedata
 
 
 def wrapaddrevision(
     orig, self, text, transaction, link, p1, p2, *args, **kwargs
 ):
     if kwargs.get('sidedata') is None:
         kwargs['sidedata'] = {}
     sd = kwargs['sidedata']
     ## let's store some arbitrary data just for testing
     # text length
     sd[sidedata.SD_TEST1] = struct.pack('>I', len(text))
     # and sha2 hashes
     sha256 = hashlib.sha256(text).digest()
     sd[sidedata.SD_TEST2] = struct.pack('>32s', sha256)
     return orig(self, text, transaction, link, p1, p2, *args, **kwargs)
 
 
 def wraprevision(orig, self, nodeorrev, *args, **kwargs):
     text = orig(self, nodeorrev, *args, **kwargs)
     if getattr(self, 'sidedatanocheck', False):
         return text
     if nodeorrev != node.nullrev and nodeorrev != node.nullid:
         sd = self.sidedata(nodeorrev)
         if len(text) != struct.unpack('>I', sd[sidedata.SD_TEST1])[0]:
             raise RuntimeError('text size mismatch')
         expected = sd[sidedata.SD_TEST2]
         got = hashlib.sha256(text).digest()
         if got != expected:
             raise RuntimeError('sha256 mismatch')
     return text
 
 
 def wrapgetsidedatacompanion(orig, srcrepo, dstrepo):
     sidedatacompanion = orig(srcrepo, dstrepo)
     addedreqs = dstrepo.requirements - srcrepo.requirements
     if requirements.SIDEDATA_REQUIREMENT in addedreqs:
         assert sidedatacompanion is None  # deal with composition later
 
         def sidedatacompanion(revlog, rev):
             update = {}
             revlog.sidedatanocheck = True
             try:
                 text = revlog.revision(rev)
             finally:
                 del revlog.sidedatanocheck
             ## let's store some arbitrary data just for testing
             # text length
             update[sidedata.SD_TEST1] = struct.pack('>I', len(text))
             # and sha2 hashes
             sha256 = hashlib.sha256(text).digest()
             update[sidedata.SD_TEST2] = struct.pack('>32s', sha256)
             return False, (), update, 0, 0
 
     return sidedatacompanion
 
 
 def extsetup(ui):
     extensions.wrapfunction(revlog.revlog, 'addrevision', wrapaddrevision)
     extensions.wrapfunction(revlog.revlog, 'revision', wraprevision)
     extensions.wrapfunction(
-        upgrade, 'getsidedatacompanion', wrapgetsidedatacompanion
+        upgrade_engine, 'getsidedatacompanion', wrapgetsidedatacompanion
     )