debugdiscovery: display some information about the initial "undecided" set

The size and shape of the revision that remains "undediced" once the fetched the
remote heads and queried the local one have a large impact on the discovery
performance, so we display some information about that set.

Differential Revision: https://phab.mercurial-scm.org/D9530

mercurial/debugcommands.py

@@ -1,4634 +1,4652
 # debugcommands.py - command processing for debug* commands
 #
 # Copyright 2005-2016 Matt Mackall <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
 from __future__ import absolute_import
 
 import codecs
 import collections
 import difflib
 import errno
 import glob
 import operator
 import os
 import platform
 import random
 import re
 import socket
 import ssl
 import stat
 import string
 import subprocess
 import sys
 import time
 
 from .i18n import _
 from .node import (
     bin,
     hex,
     nullid,
     nullrev,
     short,
 )
 from .pycompat import (
     getattr,
     open,
 )
 from . import (
     bundle2,
     bundlerepo,
     changegroup,
     cmdutil,
     color,
     context,
     copies,
     dagparser,
     encoding,
     error,
     exchange,
     extensions,
     filemerge,
     filesetlang,
     formatter,
     hg,
     httppeer,
     localrepo,
     lock as lockmod,
     logcmdutil,
     mergestate as mergestatemod,
     metadata,
     obsolete,
     obsutil,
     pathutil,
     phases,
     policy,
     pvec,
     pycompat,
     registrar,
     repair,
     revlog,
     revset,
     revsetlang,
     scmutil,
     setdiscovery,
     simplemerge,
     sshpeer,
     sslutil,
     streamclone,
     strip,
     tags as tagsmod,
     templater,
     treediscovery,
     upgrade,
     url as urlmod,
     util,
     vfs as vfsmod,
     wireprotoframing,
     wireprotoserver,
     wireprotov2peer,
 )
 from .utils import (
     cborutil,
     compression,
     dateutil,
     procutil,
     stringutil,
 )
 
 from .revlogutils import (
     deltas as deltautil,
     nodemap,
     sidedata,
 )
 
 release = lockmod.release
 
 table = {}
 table.update(strip.command._table)
 command = registrar.command(table)
 
 
 @command(b'debugancestor', [], _(b'[INDEX] REV1 REV2'), optionalrepo=True)
 def debugancestor(ui, repo, *args):
     """find the ancestor revision of two revisions in a given index"""
     if len(args) == 3:
         index, rev1, rev2 = args
         r = revlog.revlog(vfsmod.vfs(encoding.getcwd(), audit=False), index)
         lookup = r.lookup
     elif len(args) == 2:
         if not repo:
             raise error.Abort(
                 _(b'there is no Mercurial repository here (.hg not found)')
             )
         rev1, rev2 = args
         r = repo.changelog
         lookup = repo.lookup
     else:
         raise error.Abort(_(b'either two or three arguments required'))
     a = r.ancestor(lookup(rev1), lookup(rev2))
     ui.write(b'%d:%s\n' % (r.rev(a), hex(a)))
 
 
 @command(b'debugantivirusrunning', [])
 def debugantivirusrunning(ui, repo):
     """attempt to trigger an antivirus scanner to see if one is active"""
     with repo.cachevfs.open('eicar-test-file.com', b'wb') as f:
         f.write(
             util.b85decode(
                 # This is a base85-armored version of the EICAR test file. See
                 # https://en.wikipedia.org/wiki/EICAR_test_file for details.
                 b'ST#=}P$fV?P+K%yP+C|uG$>GBDK|qyDK~v2MM*<JQY}+dK~6+LQba95P'
                 b'E<)&Nm5l)EmTEQR4qnHOhq9iNGnJx'
             )
         )
     # Give an AV engine time to scan the file.
     time.sleep(2)
     util.unlink(repo.cachevfs.join('eicar-test-file.com'))
 
 
 @command(b'debugapplystreamclonebundle', [], b'FILE')
 def debugapplystreamclonebundle(ui, repo, fname):
     """apply a stream clone bundle file"""
     f = hg.openpath(ui, fname)
     gen = exchange.readbundle(ui, f, fname)
     gen.apply(repo)
 
 
 @command(
     b'debugbuilddag',
     [
         (
             b'm',
             b'mergeable-file',
             None,
             _(b'add single file mergeable changes'),
         ),
         (
             b'o',
             b'overwritten-file',
             None,
             _(b'add single file all revs overwrite'),
         ),
         (b'n', b'new-file', None, _(b'add new file at each rev')),
     ],
     _(b'[OPTION]... [TEXT]'),
 )
 def debugbuilddag(
     ui,
     repo,
     text=None,
     mergeable_file=False,
     overwritten_file=False,
     new_file=False,
 ):
     """builds a repo with a given DAG from scratch in the current empty repo
 
     The description of the DAG is read from stdin if not given on the
     command line.
 
     Elements:
 
      - "+n" is a linear run of n nodes based on the current default parent
      - "." is a single node based on the current default parent
      - "$" resets the default parent to null (implied at the start);
            otherwise the default parent is always the last node created
      - "<p" sets the default parent to the backref p
      - "*p" is a fork at parent p, which is a backref
      - "*p1/p2" is a merge of parents p1 and p2, which are backrefs
      - "/p2" is a merge of the preceding node and p2
      - ":tag" defines a local tag for the preceding node
      - "@branch" sets the named branch for subsequent nodes
      - "#...\\n" is a comment up to the end of the line
 
     Whitespace between the above elements is ignored.
 
     A backref is either
 
      - a number n, which references the node curr-n, where curr is the current
        node, or
      - the name of a local tag you placed earlier using ":tag", or
      - empty to denote the default parent.
 
     All string valued-elements are either strictly alphanumeric, or must
     be enclosed in double quotes ("..."), with "\\" as escape character.
     """
 
     if text is None:
         ui.status(_(b"reading DAG from stdin\n"))
         text = ui.fin.read()
 
     cl = repo.changelog
     if len(cl) > 0:
         raise error.Abort(_(b'repository is not empty'))
 
     # determine number of revs in DAG
     total = 0
     for type, data in dagparser.parsedag(text):
         if type == b'n':
             total += 1
 
     if mergeable_file:
         linesperrev = 2
         # make a file with k lines per rev
         initialmergedlines = [
             b'%d' % i for i in pycompat.xrange(0, total * linesperrev)
         ]
         initialmergedlines.append(b"")
 
     tags = []
     progress = ui.makeprogress(
         _(b'building'), unit=_(b'revisions'), total=total
     )
     with progress, repo.wlock(), repo.lock(), repo.transaction(b"builddag"):
         at = -1
         atbranch = b'default'
         nodeids = []
         id = 0
         progress.update(id)
         for type, data in dagparser.parsedag(text):
             if type == b'n':
                 ui.note((b'node %s\n' % pycompat.bytestr(data)))
                 id, ps = data
 
                 files = []
                 filecontent = {}
 
                 p2 = None
                 if mergeable_file:
                     fn = b"mf"
                     p1 = repo[ps[0]]
                     if len(ps) > 1:
                         p2 = repo[ps[1]]
                         pa = p1.ancestor(p2)
                         base, local, other = [
                             x[fn].data() for x in (pa, p1, p2)
                         ]
                         m3 = simplemerge.Merge3Text(base, local, other)
                         ml = [l.strip() for l in m3.merge_lines()]
                         ml.append(b"")
                     elif at > 0:
                         ml = p1[fn].data().split(b"\n")
                     else:
                         ml = initialmergedlines
                     ml[id * linesperrev] += b" r%i" % id
                     mergedtext = b"\n".join(ml)
                     files.append(fn)
                     filecontent[fn] = mergedtext
 
                 if overwritten_file:
                     fn = b"of"
                     files.append(fn)
                     filecontent[fn] = b"r%i\n" % id
 
                 if new_file:
                     fn = b"nf%i" % id
                     files.append(fn)
                     filecontent[fn] = b"r%i\n" % id
                     if len(ps) > 1:
                         if not p2:
                             p2 = repo[ps[1]]
                         for fn in p2:
                             if fn.startswith(b"nf"):
                                 files.append(fn)
                                 filecontent[fn] = p2[fn].data()
 
                 def fctxfn(repo, cx, path):
                     if path in filecontent:
                         return context.memfilectx(
                             repo, cx, path, filecontent[path]
                         )
                     return None
 
                 if len(ps) == 0 or ps[0] < 0:
                     pars = [None, None]
                 elif len(ps) == 1:
                     pars = [nodeids[ps[0]], None]
                 else:
                     pars = [nodeids[p] for p in ps]
                 cx = context.memctx(
                     repo,
                     pars,
                     b"r%i" % id,
                     files,
                     fctxfn,
                     date=(id, 0),
                     user=b"debugbuilddag",
                     extra={b'branch': atbranch},
                 )
                 nodeid = repo.commitctx(cx)
                 nodeids.append(nodeid)
                 at = id
             elif type == b'l':
                 id, name = data
                 ui.note((b'tag %s\n' % name))
                 tags.append(b"%s %s\n" % (hex(repo.changelog.node(id)), name))
             elif type == b'a':
                 ui.note((b'branch %s\n' % data))
                 atbranch = data
             progress.update(id)
 
         if tags:
             repo.vfs.write(b"localtags", b"".join(tags))
 
 
 def _debugchangegroup(ui, gen, all=None, indent=0, **opts):
     indent_string = b' ' * indent
     if all:
         ui.writenoi18n(
             b"%sformat: id, p1, p2, cset, delta base, len(delta)\n"
             % indent_string
         )
 
         def showchunks(named):
             ui.write(b"\n%s%s\n" % (indent_string, named))
             for deltadata in gen.deltaiter():
                 node, p1, p2, cs, deltabase, delta, flags = deltadata
                 ui.write(
                     b"%s%s %s %s %s %s %d\n"
                     % (
                         indent_string,
                         hex(node),
                         hex(p1),
                         hex(p2),
                         hex(cs),
                         hex(deltabase),
                         len(delta),
                     )
                 )
 
         gen.changelogheader()
         showchunks(b"changelog")
         gen.manifestheader()
         showchunks(b"manifest")
         for chunkdata in iter(gen.filelogheader, {}):
             fname = chunkdata[b'filename']
             showchunks(fname)
     else:
         if isinstance(gen, bundle2.unbundle20):
             raise error.Abort(_(b'use debugbundle2 for this file'))
         gen.changelogheader()
         for deltadata in gen.deltaiter():
             node, p1, p2, cs, deltabase, delta, flags = deltadata
             ui.write(b"%s%s\n" % (indent_string, hex(node)))
 
 
 def _debugobsmarkers(ui, part, indent=0, **opts):
     """display version and markers contained in 'data'"""
     opts = pycompat.byteskwargs(opts)
     data = part.read()
     indent_string = b' ' * indent
     try:
         version, markers = obsolete._readmarkers(data)
     except error.UnknownVersion as exc:
         msg = b"%sunsupported version: %s (%d bytes)\n"
         msg %= indent_string, exc.version, len(data)
         ui.write(msg)
     else:
         msg = b"%sversion: %d (%d bytes)\n"
         msg %= indent_string, version, len(data)
         ui.write(msg)
         fm = ui.formatter(b'debugobsolete', opts)
         for rawmarker in sorted(markers):
             m = obsutil.marker(None, rawmarker)
             fm.startitem()
             fm.plain(indent_string)
             cmdutil.showmarker(fm, m)
         fm.end()
 
 
 def _debugphaseheads(ui, data, indent=0):
     """display version and markers contained in 'data'"""
     indent_string = b' ' * indent
     headsbyphase = phases.binarydecode(data)
     for phase in phases.allphases:
         for head in headsbyphase[phase]:
             ui.write(indent_string)
             ui.write(b'%s %s\n' % (hex(head), phases.phasenames[phase]))
 
 
 def _quasirepr(thing):
     if isinstance(thing, (dict, util.sortdict, collections.OrderedDict)):
         return b'{%s}' % (
             b', '.join(b'%s: %s' % (k, thing[k]) for k in sorted(thing))
         )
     return pycompat.bytestr(repr(thing))
 
 
 def _debugbundle2(ui, gen, all=None, **opts):
     """lists the contents of a bundle2"""
     if not isinstance(gen, bundle2.unbundle20):
         raise error.Abort(_(b'not a bundle2 file'))
     ui.write((b'Stream params: %s\n' % _quasirepr(gen.params)))
     parttypes = opts.get('part_type', [])
     for part in gen.iterparts():
         if parttypes and part.type not in parttypes:
             continue
         msg = b'%s -- %s (mandatory: %r)\n'
         ui.write((msg % (part.type, _quasirepr(part.params), part.mandatory)))
         if part.type == b'changegroup':
             version = part.params.get(b'version', b'01')
             cg = changegroup.getunbundler(version, part, b'UN')
             if not ui.quiet:
                 _debugchangegroup(ui, cg, all=all, indent=4, **opts)
         if part.type == b'obsmarkers':
             if not ui.quiet:
                 _debugobsmarkers(ui, part, indent=4, **opts)
         if part.type == b'phase-heads':
             if not ui.quiet:
                 _debugphaseheads(ui, part, indent=4)
 
 
 @command(
     b'debugbundle',
     [
         (b'a', b'all', None, _(b'show all details')),
         (b'', b'part-type', [], _(b'show only the named part type')),
         (b'', b'spec', None, _(b'print the bundlespec of the bundle')),
     ],
     _(b'FILE'),
     norepo=True,
 )
 def debugbundle(ui, bundlepath, all=None, spec=None, **opts):
     """lists the contents of a bundle"""
     with hg.openpath(ui, bundlepath) as f:
         if spec:
             spec = exchange.getbundlespec(ui, f)
             ui.write(b'%s\n' % spec)
             return
 
         gen = exchange.readbundle(ui, f, bundlepath)
         if isinstance(gen, bundle2.unbundle20):
             return _debugbundle2(ui, gen, all=all, **opts)
         _debugchangegroup(ui, gen, all=all, **opts)
 
 
 @command(b'debugcapabilities', [], _(b'PATH'), norepo=True)
 def debugcapabilities(ui, path, **opts):
     """lists the capabilities of a remote peer"""
     opts = pycompat.byteskwargs(opts)
     peer = hg.peer(ui, opts, path)
     caps = peer.capabilities()
     ui.writenoi18n(b'Main capabilities:\n')
     for c in sorted(caps):
         ui.write(b'  %s\n' % c)
     b2caps = bundle2.bundle2caps(peer)
     if b2caps:
         ui.writenoi18n(b'Bundle2 capabilities:\n')
         for key, values in sorted(pycompat.iteritems(b2caps)):
             ui.write(b'  %s\n' % key)
             for v in values:
                 ui.write(b'    %s\n' % v)
 
 
 @command(b'debugchangedfiles', [], b'REV')
 def debugchangedfiles(ui, repo, rev):
     """list the stored files changes for a revision"""
     ctx = scmutil.revsingle(repo, rev, None)
     sd = repo.changelog.sidedata(ctx.rev())
     files_block = sd.get(sidedata.SD_FILES)
     if files_block is not None:
         files = metadata.decode_files_sidedata(sd)
         for f in sorted(files.touched):
             if f in files.added:
                 action = b"added"
             elif f in files.removed:
                 action = b"removed"
             elif f in files.merged:
                 action = b"merged"
             elif f in files.salvaged:
                 action = b"salvaged"
             else:
                 action = b"touched"
 
             copy_parent = b""
             copy_source = b""
             if f in files.copied_from_p1:
                 copy_parent = b"p1"
                 copy_source = files.copied_from_p1[f]
             elif f in files.copied_from_p2:
                 copy_parent = b"p2"
                 copy_source = files.copied_from_p2[f]
 
             data = (action, copy_parent, f, copy_source)
             template = b"%-8s %2s: %s, %s;\n"
             ui.write(template % data)
 
 
 @command(b'debugcheckstate', [], b'')
 def debugcheckstate(ui, repo):
     """validate the correctness of the current dirstate"""
     parent1, parent2 = repo.dirstate.parents()
     m1 = repo[parent1].manifest()
     m2 = repo[parent2].manifest()
     errors = 0
     for f in repo.dirstate:
         state = repo.dirstate[f]
         if state in b"nr" and f not in m1:
             ui.warn(_(b"%s in state %s, but not in manifest1\n") % (f, state))
             errors += 1
         if state in b"a" and f in m1:
             ui.warn(_(b"%s in state %s, but also in manifest1\n") % (f, state))
             errors += 1
         if state in b"m" and f not in m1 and f not in m2:
             ui.warn(
                 _(b"%s in state %s, but not in either manifest\n") % (f, state)
             )
             errors += 1
     for f in m1:
         state = repo.dirstate[f]
         if state not in b"nrm":
             ui.warn(_(b"%s in manifest1, but listed as state %s") % (f, state))
             errors += 1
     if errors:
         errstr = _(b".hg/dirstate inconsistent with current parent's manifest")
         raise error.Abort(errstr)
 
 
 @command(
     b'debugcolor',
     [(b'', b'style', None, _(b'show all configured styles'))],
     b'hg debugcolor',
 )
 def debugcolor(ui, repo, **opts):
     """show available color, effects or style"""
     ui.writenoi18n(b'color mode: %s\n' % stringutil.pprint(ui._colormode))
     if opts.get('style'):
         return _debugdisplaystyle(ui)
     else:
         return _debugdisplaycolor(ui)
 
 
 def _debugdisplaycolor(ui):
     ui = ui.copy()
     ui._styles.clear()
     for effect in color._activeeffects(ui).keys():
         ui._styles[effect] = effect
     if ui._terminfoparams:
         for k, v in ui.configitems(b'color'):
             if k.startswith(b'color.'):
                 ui._styles[k] = k[6:]
             elif k.startswith(b'terminfo.'):
                 ui._styles[k] = k[9:]
     ui.write(_(b'available colors:\n'))
     # sort label with a '_' after the other to group '_background' entry.
     items = sorted(ui._styles.items(), key=lambda i: (b'_' in i[0], i[0], i[1]))
     for colorname, label in items:
         ui.write(b'%s\n' % colorname, label=label)
 
 
 def _debugdisplaystyle(ui):
     ui.write(_(b'available style:\n'))
     if not ui._styles:
         return
     width = max(len(s) for s in ui._styles)
     for label, effects in sorted(ui._styles.items()):
         ui.write(b'%s' % label, label=label)
         if effects:
             # 50
             ui.write(b': ')
             ui.write(b' ' * (max(0, width - len(label))))
             ui.write(b', '.join(ui.label(e, e) for e in effects.split()))
         ui.write(b'\n')
 
 
 @command(b'debugcreatestreamclonebundle', [], b'FILE')
 def debugcreatestreamclonebundle(ui, repo, fname):
     """create a stream clone bundle file
 
     Stream bundles are special bundles that are essentially archives of
     revlog files. They are commonly used for cloning very quickly.
     """
     # TODO we may want to turn this into an abort when this functionality
     # is moved into `hg bundle`.
     if phases.hassecret(repo):
         ui.warn(
             _(
                 b'(warning: stream clone bundle will contain secret '
                 b'revisions)\n'
             )
         )
 
     requirements, gen = streamclone.generatebundlev1(repo)
     changegroup.writechunks(ui, gen, fname)
 
     ui.write(_(b'bundle requirements: %s\n') % b', '.join(sorted(requirements)))
 
 
 @command(
     b'debugdag',
     [
         (b't', b'tags', None, _(b'use tags as labels')),
         (b'b', b'branches', None, _(b'annotate with branch names')),
         (b'', b'dots', None, _(b'use dots for runs')),
         (b's', b'spaces', None, _(b'separate elements by spaces')),
     ],
     _(b'[OPTION]... [FILE [REV]...]'),
     optionalrepo=True,
 )
 def debugdag(ui, repo, file_=None, *revs, **opts):
     """format the changelog or an index DAG as a concise textual description
 
     If you pass a revlog index, the revlog's DAG is emitted. If you list
     revision numbers, they get labeled in the output as rN.
 
     Otherwise, the changelog DAG of the current repo is emitted.
     """
     spaces = opts.get('spaces')
     dots = opts.get('dots')
     if file_:
         rlog = revlog.revlog(vfsmod.vfs(encoding.getcwd(), audit=False), file_)
         revs = {int(r) for r in revs}
 
         def events():
             for r in rlog:
                 yield b'n', (r, list(p for p in rlog.parentrevs(r) if p != -1))
                 if r in revs:
                     yield b'l', (r, b"r%i" % r)
 
     elif repo:
         cl = repo.changelog
         tags = opts.get('tags')
         branches = opts.get('branches')
         if tags:
             labels = {}
             for l, n in repo.tags().items():
                 labels.setdefault(cl.rev(n), []).append(l)
 
         def events():
             b = b"default"
             for r in cl:
                 if branches:
                     newb = cl.read(cl.node(r))[5][b'branch']
                     if newb != b:
                         yield b'a', newb
                         b = newb
                 yield b'n', (r, list(p for p in cl.parentrevs(r) if p != -1))
                 if tags:
                     ls = labels.get(r)
                     if ls:
                         for l in ls:
                             yield b'l', (r, l)
 
     else:
         raise error.Abort(_(b'need repo for changelog dag'))
 
     for line in dagparser.dagtextlines(
         events(),
         addspaces=spaces,
         wraplabels=True,
         wrapannotations=True,
         wrapnonlinear=dots,
         usedots=dots,
         maxlinewidth=70,
     ):
         ui.write(line)
         ui.write(b"\n")
 
 
 @command(b'debugdata', cmdutil.debugrevlogopts, _(b'-c|-m|FILE REV'))
 def debugdata(ui, repo, file_, rev=None, **opts):
     """dump the contents of a data file revision"""
     opts = pycompat.byteskwargs(opts)
     if opts.get(b'changelog') or opts.get(b'manifest') or opts.get(b'dir'):
         if rev is not None:
             raise error.CommandError(b'debugdata', _(b'invalid arguments'))
         file_, rev = None, file_
     elif rev is None:
         raise error.CommandError(b'debugdata', _(b'invalid arguments'))
     r = cmdutil.openstorage(repo, b'debugdata', file_, opts)
     try:
         ui.write(r.rawdata(r.lookup(rev)))
     except KeyError:
         raise error.Abort(_(b'invalid revision identifier %s') % rev)
 
 
 @command(
     b'debugdate',
     [(b'e', b'extended', None, _(b'try extended date formats'))],
     _(b'[-e] DATE [RANGE]'),
     norepo=True,
     optionalrepo=True,
 )
 def debugdate(ui, date, range=None, **opts):
     """parse and display a date"""
     if opts["extended"]:
         d = dateutil.parsedate(date, dateutil.extendeddateformats)
     else:
         d = dateutil.parsedate(date)
     ui.writenoi18n(b"internal: %d %d\n" % d)
     ui.writenoi18n(b"standard: %s\n" % dateutil.datestr(d))
     if range:
         m = dateutil.matchdate(range)
         ui.writenoi18n(b"match: %s\n" % m(d[0]))
 
 
 @command(
     b'debugdeltachain',
     cmdutil.debugrevlogopts + cmdutil.formatteropts,
     _(b'-c|-m|FILE'),
     optionalrepo=True,
 )
 def debugdeltachain(ui, repo, file_=None, **opts):
     """dump information about delta chains in a revlog
 
     Output can be templatized. Available template keywords are:
 
     :``rev``:       revision number
     :``chainid``:   delta chain identifier (numbered by unique base)
     :``chainlen``:  delta chain length to this revision
     :``prevrev``:   previous revision in delta chain
     :``deltatype``: role of delta / how it was computed
     :``compsize``:  compressed size of revision
     :``uncompsize``: uncompressed size of revision
     :``chainsize``: total size of compressed revisions in chain
     :``chainratio``: total chain size divided by uncompressed revision size
                     (new delta chains typically start at ratio 2.00)
     :``lindist``:   linear distance from base revision in delta chain to end
                     of this revision
     :``extradist``: total size of revisions not part of this delta chain from
                     base of delta chain to end of this revision; a measurement
                     of how much extra data we need to read/seek across to read
                     the delta chain for this revision
     :``extraratio``: extradist divided by chainsize; another representation of
                     how much unrelated data is needed to load this delta chain
 
     If the repository is configured to use the sparse read, additional keywords
     are available:
 
     :``readsize``:     total size of data read from the disk for a revision
                        (sum of the sizes of all the blocks)
     :``largestblock``: size of the largest block of data read from the disk
     :``readdensity``:  density of useful bytes in the data read from the disk
     :``srchunks``:  in how many data hunks the whole revision would be read
 
     The sparse read can be enabled with experimental.sparse-read = True
     """
     opts = pycompat.byteskwargs(opts)
     r = cmdutil.openrevlog(repo, b'debugdeltachain', file_, opts)
     index = r.index
     start = r.start
     length = r.length
     generaldelta = r.version & revlog.FLAG_GENERALDELTA
     withsparseread = getattr(r, '_withsparseread', False)
 
     def revinfo(rev):
         e = index[rev]
         compsize = e[1]
         uncompsize = e[2]
         chainsize = 0
 
         if generaldelta:
             if e[3] == e[5]:
                 deltatype = b'p1'
             elif e[3] == e[6]:
                 deltatype = b'p2'
             elif e[3] == rev - 1:
                 deltatype = b'prev'
             elif e[3] == rev:
                 deltatype = b'base'
             else:
                 deltatype = b'other'
         else:
             if e[3] == rev:
                 deltatype = b'base'
             else:
                 deltatype = b'prev'
 
         chain = r._deltachain(rev)[0]
         for iterrev in chain:
             e = index[iterrev]
             chainsize += e[1]
 
         return compsize, uncompsize, deltatype, chain, chainsize
 
     fm = ui.formatter(b'debugdeltachain', opts)
 
     fm.plain(
         b'    rev  chain# chainlen     prev   delta       '
         b'size    rawsize  chainsize     ratio   lindist extradist '
         b'extraratio'
     )
     if withsparseread:
         fm.plain(b'   readsize largestblk rddensity srchunks')
     fm.plain(b'\n')
 
     chainbases = {}
     for rev in r:
         comp, uncomp, deltatype, chain, chainsize = revinfo(rev)
         chainbase = chain[0]
         chainid = chainbases.setdefault(chainbase, len(chainbases) + 1)
         basestart = start(chainbase)
         revstart = start(rev)
         lineardist = revstart + comp - basestart
         extradist = lineardist - chainsize
         try:
             prevrev = chain[-2]
         except IndexError:
             prevrev = -1
 
         if uncomp != 0:
             chainratio = float(chainsize) / float(uncomp)
         else:
             chainratio = chainsize
 
         if chainsize != 0:
             extraratio = float(extradist) / float(chainsize)
         else:
             extraratio = extradist
 
         fm.startitem()
         fm.write(
             b'rev chainid chainlen prevrev deltatype compsize '
             b'uncompsize chainsize chainratio lindist extradist '
             b'extraratio',
             b'%7d %7d %8d %8d %7s %10d %10d %10d %9.5f %9d %9d %10.5f',
             rev,
             chainid,
             len(chain),
             prevrev,
             deltatype,
             comp,
             uncomp,
             chainsize,
             chainratio,
             lineardist,
             extradist,
             extraratio,
             rev=rev,
             chainid=chainid,
             chainlen=len(chain),
             prevrev=prevrev,
             deltatype=deltatype,
             compsize=comp,
             uncompsize=uncomp,
             chainsize=chainsize,
             chainratio=chainratio,
             lindist=lineardist,
             extradist=extradist,
             extraratio=extraratio,
         )
         if withsparseread:
             readsize = 0
             largestblock = 0
             srchunks = 0
 
             for revschunk in deltautil.slicechunk(r, chain):
                 srchunks += 1
                 blkend = start(revschunk[-1]) + length(revschunk[-1])
                 blksize = blkend - start(revschunk[0])
 
                 readsize += blksize
                 if largestblock < blksize:
                     largestblock = blksize
 
             if readsize:
                 readdensity = float(chainsize) / float(readsize)
             else:
                 readdensity = 1
 
             fm.write(
                 b'readsize largestblock readdensity srchunks',
                 b' %10d %10d %9.5f %8d',
                 readsize,
                 largestblock,
                 readdensity,
                 srchunks,
                 readsize=readsize,
                 largestblock=largestblock,
                 readdensity=readdensity,
                 srchunks=srchunks,
             )
 
         fm.plain(b'\n')
 
     fm.end()
 
 
 @command(
     b'debugdirstate|debugstate',
     [
         (
             b'',
             b'nodates',
             None,
             _(b'do not display the saved mtime (DEPRECATED)'),
         ),
         (b'', b'dates', True, _(b'display the saved mtime')),
         (b'', b'datesort', None, _(b'sort by saved mtime')),
     ],
     _(b'[OPTION]...'),
 )
 def debugstate(ui, repo, **opts):
     """show the contents of the current dirstate"""
 
     nodates = not opts['dates']
     if opts.get('nodates') is not None:
         nodates = True
     datesort = opts.get('datesort')
 
     if datesort:
         keyfunc = lambda x: (x[1][3], x[0])  # sort by mtime, then by filename
     else:
         keyfunc = None  # sort by filename
     for file_, ent in sorted(pycompat.iteritems(repo.dirstate), key=keyfunc):
         if ent[3] == -1:
             timestr = b'unset               '
         elif nodates:
             timestr = b'set                 '
         else:
             timestr = time.strftime(
                 "%Y-%m-%d %H:%M:%S ", time.localtime(ent[3])
             )
             timestr = encoding.strtolocal(timestr)
         if ent[1] & 0o20000:
             mode = b'lnk'
         else:
             mode = b'%3o' % (ent[1] & 0o777 & ~util.umask)
         ui.write(b"%c %s %10d %s%s\n" % (ent[0], mode, ent[2], timestr, file_))
     for f in repo.dirstate.copies():
         ui.write(_(b"copy: %s -> %s\n") % (repo.dirstate.copied(f), f))
 
 
 @command(
     b'debugdiscovery',
     [
         (b'', b'old', None, _(b'use old-style discovery')),
         (
             b'',
             b'nonheads',
             None,
             _(b'use old-style discovery with non-heads included'),
         ),
         (b'', b'rev', [], b'restrict discovery to this set of revs'),
         (b'', b'seed', b'12323', b'specify the random seed use for discovery'),
     ]
     + cmdutil.remoteopts,
     _(b'[--rev REV] [OTHER]'),
 )
 def debugdiscovery(ui, repo, remoteurl=b"default", **opts):
     """runs the changeset discovery protocol in isolation"""
     opts = pycompat.byteskwargs(opts)
     remoteurl, branches = hg.parseurl(ui.expandpath(remoteurl))
     remote = hg.peer(repo, opts, remoteurl)
     ui.status(_(b'comparing with %s\n') % util.hidepassword(remoteurl))
 
     # make sure tests are repeatable
     random.seed(int(opts[b'seed']))
 
     if opts.get(b'old'):
 
         def doit(pushedrevs, remoteheads, remote=remote):
             if not util.safehasattr(remote, b'branches'):
                 # enable in-client legacy support
                 remote = localrepo.locallegacypeer(remote.local())
             common, _in, hds = treediscovery.findcommonincoming(
                 repo, remote, force=True
             )
             common = set(common)
             if not opts.get(b'nonheads'):
                 ui.writenoi18n(
                     b"unpruned common: %s\n"
                     % b" ".join(sorted(short(n) for n in common))
                 )
 
                 clnode = repo.changelog.node
                 common = repo.revs(b'heads(::%ln)', common)
                 common = {clnode(r) for r in common}
             return common, hds
 
     else:
 
         def doit(pushedrevs, remoteheads, remote=remote):
             nodes = None
             if pushedrevs:
                 revs = scmutil.revrange(repo, pushedrevs)
                 nodes = [repo[r].node() for r in revs]
             common, any, hds = setdiscovery.findcommonheads(
                 ui, repo, remote, ancestorsof=nodes
             )
             return common, hds
 
     remoterevs, _checkout = hg.addbranchrevs(repo, remote, branches, revs=None)
     localrevs = opts[b'rev']
     with util.timedcm('debug-discovery') as t:
         common, hds = doit(localrevs, remoterevs)
 
     # compute all statistics
     heads_common = set(common)
     heads_remote = set(hds)
     heads_local = set(repo.heads())
     # note: they cannot be a local or remote head that is in common and not
     # itself a head of common.
     heads_common_local = heads_common & heads_local
     heads_common_remote = heads_common & heads_remote
     heads_common_both = heads_common & heads_remote & heads_local
 
     all = repo.revs(b'all()')
     common = repo.revs(b'::%ln', common)
     roots_common = repo.revs(b'roots(::%ld)', common)
     missing = repo.revs(b'not ::%ld', common)
     heads_missing = repo.revs(b'heads(%ld)', missing)
     roots_missing = repo.revs(b'roots(%ld)', missing)
     assert len(common) + len(missing) == len(all)
 
+    initial_undecided = repo.revs(
+        b'not (::%ln or %ln::)', heads_common_remote, heads_common_local
+    )
+    heads_initial_undecided = repo.revs(b'heads(%ld)', initial_undecided)
+    roots_initial_undecided = repo.revs(b'roots(%ld)', initial_undecided)
+    common_initial_undecided = initial_undecided & common
+    missing_initial_undecided = initial_undecided & missing
+
     data = {}
     data[b'elapsed'] = t.elapsed
     data[b'nb-common-heads'] = len(heads_common)
     data[b'nb-common-heads-local'] = len(heads_common_local)
     data[b'nb-common-heads-remote'] = len(heads_common_remote)
     data[b'nb-common-heads-both'] = len(heads_common_both)
     data[b'nb-common-roots'] = len(roots_common)
     data[b'nb-head-local'] = len(heads_local)
     data[b'nb-head-local-missing'] = len(heads_local) - len(heads_common_local)
     data[b'nb-head-remote'] = len(heads_remote)
     data[b'nb-head-remote-unknown'] = len(heads_remote) - len(
         heads_common_remote
     )
     data[b'nb-revs'] = len(all)
     data[b'nb-revs-common'] = len(common)
     data[b'nb-revs-missing'] = len(missing)
     data[b'nb-missing-heads'] = len(roots_missing)
     data[b'nb-missing-roots'] = len(heads_missing)
+    data[b'nb-ini_und'] = len(initial_undecided)
+    data[b'nb-ini_und-heads'] = len(heads_initial_undecided)
+    data[b'nb-ini_und-roots'] = len(roots_initial_undecided)
+    data[b'nb-ini_und-common'] = len(common_initial_undecided)
+    data[b'nb-ini_und-missing'] = len(missing_initial_undecided)
 
     # display discovery summary
     ui.writenoi18n(b"elapsed time:  %(elapsed)f seconds\n" % data)
     ui.writenoi18n(b"heads summary:\n")
     ui.writenoi18n(b"  total common heads:  %(nb-common-heads)9d\n" % data)
     ui.writenoi18n(
         b"    also local heads:  %(nb-common-heads-local)9d\n" % data
     )
     ui.writenoi18n(
         b"    also remote heads: %(nb-common-heads-remote)9d\n" % data
     )
     ui.writenoi18n(b"    both:              %(nb-common-heads-both)9d\n" % data)
     ui.writenoi18n(b"  local heads:         %(nb-head-local)9d\n" % data)
     ui.writenoi18n(
         b"    common:            %(nb-common-heads-local)9d\n" % data
     )
     ui.writenoi18n(
         b"    missing:           %(nb-head-local-missing)9d\n" % data
     )
     ui.writenoi18n(b"  remote heads:        %(nb-head-remote)9d\n" % data)
     ui.writenoi18n(
         b"    common:            %(nb-common-heads-remote)9d\n" % data
     )
     ui.writenoi18n(
         b"    unknown:           %(nb-head-remote-unknown)9d\n" % data
     )
     ui.writenoi18n(b"local changesets:      %(nb-revs)9d\n" % data)
     ui.writenoi18n(b"  common:              %(nb-revs-common)9d\n" % data)
     ui.writenoi18n(b"    heads:             %(nb-common-heads)9d\n" % data)
     ui.writenoi18n(b"    roots:             %(nb-common-roots)9d\n" % data)
     ui.writenoi18n(b"  missing:             %(nb-revs-missing)9d\n" % data)
     ui.writenoi18n(b"    heads:             %(nb-missing-heads)9d\n" % data)
     ui.writenoi18n(b"    roots:             %(nb-missing-roots)9d\n" % data)
+    ui.writenoi18n(b"  first undecided set: %(nb-ini_und)9d\n" % data)
+    ui.writenoi18n(b"    heads:             %(nb-ini_und-heads)9d\n" % data)
+    ui.writenoi18n(b"    roots:             %(nb-ini_und-roots)9d\n" % data)
+    ui.writenoi18n(b"    common:            %(nb-ini_und-common)9d\n" % data)
+    ui.writenoi18n(b"    missing:           %(nb-ini_und-missing)9d\n" % data)
 
     if ui.verbose:
         ui.writenoi18n(
             b"common heads: %s\n"
             % b" ".join(sorted(short(n) for n in heads_common))
         )
 
 
 _chunksize = 4 << 10
 
 
 @command(
     b'debugdownload',
     [
         (b'o', b'output', b'', _(b'path')),
     ],
     optionalrepo=True,
 )
 def debugdownload(ui, repo, url, output=None, **opts):
     """download a resource using Mercurial logic and config"""
     fh = urlmod.open(ui, url, output)
 
     dest = ui
     if output:
         dest = open(output, b"wb", _chunksize)
     try:
         data = fh.read(_chunksize)
         while data:
             dest.write(data)
             data = fh.read(_chunksize)
     finally:
         if output:
             dest.close()
 
 
 @command(b'debugextensions', cmdutil.formatteropts, [], optionalrepo=True)
 def debugextensions(ui, repo, **opts):
     '''show information about active extensions'''
     opts = pycompat.byteskwargs(opts)
     exts = extensions.extensions(ui)
     hgver = util.version()
     fm = ui.formatter(b'debugextensions', opts)
     for extname, extmod in sorted(exts, key=operator.itemgetter(0)):
         isinternal = extensions.ismoduleinternal(extmod)
         extsource = None
 
         if util.safehasattr(extmod, '__file__'):
             extsource = pycompat.fsencode(extmod.__file__)
         elif getattr(sys, 'oxidized', False):
             extsource = pycompat.sysexecutable
         if isinternal:
             exttestedwith = []  # never expose magic string to users
         else:
             exttestedwith = getattr(extmod, 'testedwith', b'').split()
         extbuglink = getattr(extmod, 'buglink', None)
 
         fm.startitem()
 
         if ui.quiet or ui.verbose:
             fm.write(b'name', b'%s\n', extname)
         else:
             fm.write(b'name', b'%s', extname)
             if isinternal or hgver in exttestedwith:
                 fm.plain(b'\n')
             elif not exttestedwith:
                 fm.plain(_(b' (untested!)\n'))
             else:
                 lasttestedversion = exttestedwith[-1]
                 fm.plain(b' (%s!)\n' % lasttestedversion)
 
         fm.condwrite(
             ui.verbose and extsource,
             b'source',
             _(b'  location: %s\n'),
             extsource or b"",
         )
 
         if ui.verbose:
             fm.plain(_(b'  bundled: %s\n') % [b'no', b'yes'][isinternal])
         fm.data(bundled=isinternal)
 
         fm.condwrite(
             ui.verbose and exttestedwith,
             b'testedwith',
             _(b'  tested with: %s\n'),
             fm.formatlist(exttestedwith, name=b'ver'),
         )
 
         fm.condwrite(
             ui.verbose and extbuglink,
             b'buglink',
             _(b'  bug reporting: %s\n'),
             extbuglink or b"",
         )
 
     fm.end()
 
 
 @command(
     b'debugfileset',
     [
         (
             b'r',
             b'rev',
             b'',
             _(b'apply the filespec on this revision'),
             _(b'REV'),
         ),
         (
             b'',
             b'all-files',
             False,
             _(b'test files from all revisions and working directory'),
         ),
         (
             b's',
             b'show-matcher',
             None,
             _(b'print internal representation of matcher'),
         ),
         (
             b'p',
             b'show-stage',
             [],
             _(b'print parsed tree at the given stage'),
             _(b'NAME'),
         ),
     ],
     _(b'[-r REV] [--all-files] [OPTION]... FILESPEC'),
 )
 def debugfileset(ui, repo, expr, **opts):
     '''parse and apply a fileset specification'''
     from . import fileset
 
     fileset.symbols  # force import of fileset so we have predicates to optimize
     opts = pycompat.byteskwargs(opts)
     ctx = scmutil.revsingle(repo, opts.get(b'rev'), None)
 
     stages = [
         (b'parsed', pycompat.identity),
         (b'analyzed', filesetlang.analyze),
         (b'optimized', filesetlang.optimize),
     ]
     stagenames = {n for n, f in stages}
 
     showalways = set()
     if ui.verbose and not opts[b'show_stage']:
         # show parsed tree by --verbose (deprecated)
         showalways.add(b'parsed')
     if opts[b'show_stage'] == [b'all']:
         showalways.update(stagenames)
     else:
         for n in opts[b'show_stage']:
             if n not in stagenames:
                 raise error.Abort(_(b'invalid stage name: %s') % n)
         showalways.update(opts[b'show_stage'])
 
     tree = filesetlang.parse(expr)
     for n, f in stages:
         tree = f(tree)
         if n in showalways:
             if opts[b'show_stage'] or n != b'parsed':
                 ui.write(b"* %s:\n" % n)
             ui.write(filesetlang.prettyformat(tree), b"\n")
 
     files = set()
     if opts[b'all_files']:
         for r in repo:
             c = repo[r]
             files.update(c.files())
             files.update(c.substate)
     if opts[b'all_files'] or ctx.rev() is None:
         wctx = repo[None]
         files.update(
             repo.dirstate.walk(
                 scmutil.matchall(repo),
                 subrepos=list(wctx.substate),
                 unknown=True,
                 ignored=True,
             )
         )
         files.update(wctx.substate)
     else:
         files.update(ctx.files())
         files.update(ctx.substate)
 
     m = ctx.matchfileset(repo.getcwd(), expr)
     if opts[b'show_matcher'] or (opts[b'show_matcher'] is None and ui.verbose):
         ui.writenoi18n(b'* matcher:\n', stringutil.prettyrepr(m), b'\n')
     for f in sorted(files):
         if not m(f):
             continue
         ui.write(b"%s\n" % f)
 
 
 @command(b'debugformat', [] + cmdutil.formatteropts)
 def debugformat(ui, repo, **opts):
     """display format information about the current repository
 
     Use --verbose to get extra information about current config value and
     Mercurial default."""
     opts = pycompat.byteskwargs(opts)
     maxvariantlength = max(len(fv.name) for fv in upgrade.allformatvariant)
     maxvariantlength = max(len(b'format-variant'), maxvariantlength)
 
     def makeformatname(name):
         return b'%s:' + (b' ' * (maxvariantlength - len(name)))
 
     fm = ui.formatter(b'debugformat', opts)
     if fm.isplain():
 
         def formatvalue(value):
             if util.safehasattr(value, b'startswith'):
                 return value
             if value:
                 return b'yes'
             else:
                 return b'no'
 
     else:
         formatvalue = pycompat.identity
 
     fm.plain(b'format-variant')
     fm.plain(b' ' * (maxvariantlength - len(b'format-variant')))
     fm.plain(b' repo')
     if ui.verbose:
         fm.plain(b' config default')
     fm.plain(b'\n')
     for fv in upgrade.allformatvariant:
         fm.startitem()
         repovalue = fv.fromrepo(repo)
         configvalue = fv.fromconfig(repo)
 
         if repovalue != configvalue:
             namelabel = b'formatvariant.name.mismatchconfig'
             repolabel = b'formatvariant.repo.mismatchconfig'
         elif repovalue != fv.default:
             namelabel = b'formatvariant.name.mismatchdefault'
             repolabel = b'formatvariant.repo.mismatchdefault'
         else:
             namelabel = b'formatvariant.name.uptodate'
             repolabel = b'formatvariant.repo.uptodate'
 
         fm.write(b'name', makeformatname(fv.name), fv.name, label=namelabel)
         fm.write(b'repo', b' %3s', formatvalue(repovalue), label=repolabel)
         if fv.default != configvalue:
             configlabel = b'formatvariant.config.special'
         else:
             configlabel = b'formatvariant.config.default'
         fm.condwrite(
             ui.verbose,
             b'config',
             b' %6s',
             formatvalue(configvalue),
             label=configlabel,
         )
         fm.condwrite(
             ui.verbose,
             b'default',
             b' %7s',
             formatvalue(fv.default),
             label=b'formatvariant.default',
         )
         fm.plain(b'\n')
     fm.end()
 
 
 @command(b'debugfsinfo', [], _(b'[PATH]'), norepo=True)
 def debugfsinfo(ui, path=b"."):
     """show information detected about current filesystem"""
     ui.writenoi18n(b'path: %s\n' % path)
     ui.writenoi18n(
         b'mounted on: %s\n' % (util.getfsmountpoint(path) or b'(unknown)')
     )
     ui.writenoi18n(b'exec: %s\n' % (util.checkexec(path) and b'yes' or b'no'))
     ui.writenoi18n(b'fstype: %s\n' % (util.getfstype(path) or b'(unknown)'))
     ui.writenoi18n(
         b'symlink: %s\n' % (util.checklink(path) and b'yes' or b'no')
     )
     ui.writenoi18n(
         b'hardlink: %s\n' % (util.checknlink(path) and b'yes' or b'no')
     )
     casesensitive = b'(unknown)'
     try:
         with pycompat.namedtempfile(prefix=b'.debugfsinfo', dir=path) as f:
             casesensitive = util.fscasesensitive(f.name) and b'yes' or b'no'
     except OSError:
         pass
     ui.writenoi18n(b'case-sensitive: %s\n' % casesensitive)
 
 
 @command(
     b'debuggetbundle',
     [
         (b'H', b'head', [], _(b'id of head node'), _(b'ID')),
         (b'C', b'common', [], _(b'id of common node'), _(b'ID')),
         (
             b't',
             b'type',
             b'bzip2',
             _(b'bundle compression type to use'),
             _(b'TYPE'),
         ),
     ],
     _(b'REPO FILE [-H|-C ID]...'),
     norepo=True,
 )
 def debuggetbundle(ui, repopath, bundlepath, head=None, common=None, **opts):
     """retrieves a bundle from a repo
 
     Every ID must be a full-length hex node id string. Saves the bundle to the
     given file.
     """
     opts = pycompat.byteskwargs(opts)
     repo = hg.peer(ui, opts, repopath)
     if not repo.capable(b'getbundle'):
         raise error.Abort(b"getbundle() not supported by target repository")
     args = {}
     if common:
         args['common'] = [bin(s) for s in common]
     if head:
         args['heads'] = [bin(s) for s in head]
     # TODO: get desired bundlecaps from command line.
     args['bundlecaps'] = None
     bundle = repo.getbundle(b'debug', **args)
 
     bundletype = opts.get(b'type', b'bzip2').lower()
     btypes = {
         b'none': b'HG10UN',
         b'bzip2': b'HG10BZ',
         b'gzip': b'HG10GZ',
         b'bundle2': b'HG20',
     }
     bundletype = btypes.get(bundletype)
     if bundletype not in bundle2.bundletypes:
         raise error.Abort(_(b'unknown bundle type specified with --type'))
     bundle2.writebundle(ui, bundle, bundlepath, bundletype)
 
 
 @command(b'debugignore', [], b'[FILE]')
 def debugignore(ui, repo, *files, **opts):
     """display the combined ignore pattern and information about ignored files
 
     With no argument display the combined ignore pattern.
 
     Given space separated file names, shows if the given file is ignored and
     if so, show the ignore rule (file and line number) that matched it.
     """
     ignore = repo.dirstate._ignore
     if not files:
         # Show all the patterns
         ui.write(b"%s\n" % pycompat.byterepr(ignore))
     else:
         m = scmutil.match(repo[None], pats=files)
         uipathfn = scmutil.getuipathfn(repo, legacyrelativevalue=True)
         for f in m.files():
             nf = util.normpath(f)
             ignored = None
             ignoredata = None
             if nf != b'.':
                 if ignore(nf):
                     ignored = nf
                     ignoredata = repo.dirstate._ignorefileandline(nf)
                 else:
                     for p in pathutil.finddirs(nf):
                         if ignore(p):
                             ignored = p
                             ignoredata = repo.dirstate._ignorefileandline(p)
                             break
             if ignored:
                 if ignored == nf:
                     ui.write(_(b"%s is ignored\n") % uipathfn(f))
                 else:
                     ui.write(
                         _(
                             b"%s is ignored because of "
                             b"containing directory %s\n"
                         )
                         % (uipathfn(f), ignored)
                     )
                 ignorefile, lineno, line = ignoredata
                 ui.write(
                     _(b"(ignore rule in %s, line %d: '%s')\n")
                     % (ignorefile, lineno, line)
                 )
             else:
                 ui.write(_(b"%s is not ignored\n") % uipathfn(f))
 
 
 @command(
     b'debugindex',
     cmdutil.debugrevlogopts + cmdutil.formatteropts,
     _(b'-c|-m|FILE'),
 )
 def debugindex(ui, repo, file_=None, **opts):
     """dump index data for a storage primitive"""
     opts = pycompat.byteskwargs(opts)
     store = cmdutil.openstorage(repo, b'debugindex', file_, opts)
 
     if ui.debugflag:
         shortfn = hex
     else:
         shortfn = short
 
     idlen = 12
     for i in store:
         idlen = len(shortfn(store.node(i)))
         break
 
     fm = ui.formatter(b'debugindex', opts)
     fm.plain(
         b'   rev linkrev %s %s p2\n'
         % (b'nodeid'.ljust(idlen), b'p1'.ljust(idlen))
     )
 
     for rev in store:
         node = store.node(rev)
         parents = store.parents(node)
 
         fm.startitem()
         fm.write(b'rev', b'%6d ', rev)
         fm.write(b'linkrev', b'%7d ', store.linkrev(rev))
         fm.write(b'node', b'%s ', shortfn(node))
         fm.write(b'p1', b'%s ', shortfn(parents[0]))
         fm.write(b'p2', b'%s', shortfn(parents[1]))
         fm.plain(b'\n')
 
     fm.end()
 
 
 @command(
     b'debugindexdot',
     cmdutil.debugrevlogopts,
     _(b'-c|-m|FILE'),
     optionalrepo=True,
 )
 def debugindexdot(ui, repo, file_=None, **opts):
     """dump an index DAG as a graphviz dot file"""
     opts = pycompat.byteskwargs(opts)
     r = cmdutil.openstorage(repo, b'debugindexdot', file_, opts)
     ui.writenoi18n(b"digraph G {\n")
     for i in r:
         node = r.node(i)
         pp = r.parents(node)
         ui.write(b"\t%d -> %d\n" % (r.rev(pp[0]), i))
         if pp[1] != nullid:
             ui.write(b"\t%d -> %d\n" % (r.rev(pp[1]), i))
     ui.write(b"}\n")
 
 
 @command(b'debugindexstats', [])
 def debugindexstats(ui, repo):
     """show stats related to the changelog index"""
     repo.changelog.shortest(nullid, 1)
     index = repo.changelog.index
     if not util.safehasattr(index, b'stats'):
         raise error.Abort(_(b'debugindexstats only works with native code'))
     for k, v in sorted(index.stats().items()):
         ui.write(b'%s: %d\n' % (k, v))
 
 
 @command(b'debuginstall', [] + cmdutil.formatteropts, b'', norepo=True)
 def debuginstall(ui, **opts):
     """test Mercurial installation
 
     Returns 0 on success.
     """
     opts = pycompat.byteskwargs(opts)
 
     problems = 0
 
     fm = ui.formatter(b'debuginstall', opts)
     fm.startitem()
 
     # encoding might be unknown or wrong. don't translate these messages.
     fm.write(b'encoding', b"checking encoding (%s)...\n", encoding.encoding)
     err = None
     try:
         codecs.lookup(pycompat.sysstr(encoding.encoding))
     except LookupError as inst:
         err = stringutil.forcebytestr(inst)
         problems += 1
     fm.condwrite(
         err,
         b'encodingerror',
         b" %s\n (check that your locale is properly set)\n",
         err,
     )
 
     # Python
     pythonlib = None
     if util.safehasattr(os, '__file__'):
         pythonlib = os.path.dirname(pycompat.fsencode(os.__file__))
     elif getattr(sys, 'oxidized', False):
         pythonlib = pycompat.sysexecutable
 
     fm.write(
         b'pythonexe',
         _(b"checking Python executable (%s)\n"),
         pycompat.sysexecutable or _(b"unknown"),
     )
     fm.write(
         b'pythonimplementation',
         _(b"checking Python implementation (%s)\n"),
         pycompat.sysbytes(platform.python_implementation()),
     )
     fm.write(
         b'pythonver',
         _(b"checking Python version (%s)\n"),
         (b"%d.%d.%d" % sys.version_info[:3]),
     )
     fm.write(
         b'pythonlib',
         _(b"checking Python lib (%s)...\n"),
         pythonlib or _(b"unknown"),
     )
 
     try:
         from . import rustext
 
         rustext.__doc__  # trigger lazy import
     except ImportError:
         rustext = None
 
     security = set(sslutil.supportedprotocols)
     if sslutil.hassni:
         security.add(b'sni')
 
     fm.write(
         b'pythonsecurity',
         _(b"checking Python security support (%s)\n"),
         fm.formatlist(sorted(security), name=b'protocol', fmt=b'%s', sep=b','),
     )
 
     # These are warnings, not errors. So don't increment problem count. This
     # may change in the future.
     if b'tls1.2' not in security:
         fm.plain(
             _(
                 b'  TLS 1.2 not supported by Python install; '
                 b'network connections lack modern security\n'
             )
         )
     if b'sni' not in security:
         fm.plain(
             _(
                 b'  SNI not supported by Python install; may have '
                 b'connectivity issues with some servers\n'
             )
         )
 
     fm.plain(
         _(
             b"checking Rust extensions (%s)\n"
             % (b'missing' if rustext is None else b'installed')
         ),
     )
 
     # TODO print CA cert info
 
     # hg version
     hgver = util.version()
     fm.write(
         b'hgver', _(b"checking Mercurial version (%s)\n"), hgver.split(b'+')[0]
     )
     fm.write(
         b'hgverextra',
         _(b"checking Mercurial custom build (%s)\n"),
         b'+'.join(hgver.split(b'+')[1:]),
     )
 
     # compiled modules
     hgmodules = None
     if util.safehasattr(sys.modules[__name__], '__file__'):
         hgmodules = os.path.dirname(pycompat.fsencode(__file__))
     elif getattr(sys, 'oxidized', False):
         hgmodules = pycompat.sysexecutable
 
     fm.write(
         b'hgmodulepolicy', _(b"checking module policy (%s)\n"), policy.policy
     )
     fm.write(
         b'hgmodules',
         _(b"checking installed modules (%s)...\n"),
         hgmodules or _(b"unknown"),
     )
 
     rustandc = policy.policy in (b'rust+c', b'rust+c-allow')
     rustext = rustandc  # for now, that's the only case
     cext = policy.policy in (b'c', b'allow') or rustandc
     nopure = cext or rustext
     if nopure:
         err = None
         try:
             if cext:
                 from .cext import (  # pytype: disable=import-error
                     base85,
                     bdiff,
                     mpatch,
                     osutil,
                 )
 
                 # quiet pyflakes
                 dir(bdiff), dir(mpatch), dir(base85), dir(osutil)
             if rustext:
                 from .rustext import (  # pytype: disable=import-error
                     ancestor,
                     dirstate,
                 )
 
                 dir(ancestor), dir(dirstate)  # quiet pyflakes
         except Exception as inst:
             err = stringutil.forcebytestr(inst)
             problems += 1
         fm.condwrite(err, b'extensionserror', b" %s\n", err)
 
     compengines = util.compengines._engines.values()
     fm.write(
         b'compengines',
         _(b'checking registered compression engines (%s)\n'),
         fm.formatlist(
             sorted(e.name() for e in compengines),
             name=b'compengine',
             fmt=b'%s',
             sep=b', ',
         ),
     )
     fm.write(
         b'compenginesavail',
         _(b'checking available compression engines (%s)\n'),
         fm.formatlist(
             sorted(e.name() for e in compengines if e.available()),
             name=b'compengine',
             fmt=b'%s',
             sep=b', ',
         ),
     )
     wirecompengines = compression.compengines.supportedwireengines(
         compression.SERVERROLE
     )
     fm.write(
         b'compenginesserver',
         _(
             b'checking available compression engines '
             b'for wire protocol (%s)\n'
         ),
         fm.formatlist(
             [e.name() for e in wirecompengines if e.wireprotosupport()],
             name=b'compengine',
             fmt=b'%s',
             sep=b', ',
         ),
     )
     re2 = b'missing'
     if util._re2:
         re2 = b'available'
     fm.plain(_(b'checking "re2" regexp engine (%s)\n') % re2)
     fm.data(re2=bool(util._re2))
 
     # templates
     p = templater.templatedir()
     fm.write(b'templatedirs', b'checking templates (%s)...\n', p or b'')
     fm.condwrite(not p, b'', _(b" no template directories found\n"))
     if p:
         (m, fp) = templater.try_open_template(b"map-cmdline.default")
         if m:
             # template found, check if it is working
             err = None
             try:
                 templater.templater.frommapfile(m)
             except Exception as inst:
                 err = stringutil.forcebytestr(inst)
                 p = None
             fm.condwrite(err, b'defaulttemplateerror', b" %s\n", err)
         else:
             p = None
         fm.condwrite(
             p, b'defaulttemplate', _(b"checking default template (%s)\n"), m
         )
         fm.condwrite(
             not m,
             b'defaulttemplatenotfound',
             _(b" template '%s' not found\n"),
             b"default",
         )
     if not p:
         problems += 1
     fm.condwrite(
         not p, b'', _(b" (templates seem to have been installed incorrectly)\n")
     )
 
     # editor
     editor = ui.geteditor()
     editor = util.expandpath(editor)
     editorbin = procutil.shellsplit(editor)[0]
     fm.write(b'editor', _(b"checking commit editor... (%s)\n"), editorbin)
     cmdpath = procutil.findexe(editorbin)
     fm.condwrite(
         not cmdpath and editor == b'vi',
         b'vinotfound',
         _(
             b" No commit editor set and can't find %s in PATH\n"
             b" (specify a commit editor in your configuration"
             b" file)\n"
         ),
         not cmdpath and editor == b'vi' and editorbin,
     )
     fm.condwrite(
         not cmdpath and editor != b'vi',
         b'editornotfound',
         _(
             b" Can't find editor '%s' in PATH\n"
             b" (specify a commit editor in your configuration"
             b" file)\n"
         ),
         not cmdpath and editorbin,
     )
     if not cmdpath and editor != b'vi':
         problems += 1
 
     # check username
     username = None
     err = None
     try:
         username = ui.username()
     except error.Abort as e:
         err = e.message
         problems += 1
 
     fm.condwrite(
         username, b'username', _(b"checking username (%s)\n"), username
     )
     fm.condwrite(
         err,
         b'usernameerror',
         _(
             b"checking username...\n %s\n"
             b" (specify a username in your configuration file)\n"
         ),
         err,
     )
 
     for name, mod in extensions.extensions():
         handler = getattr(mod, 'debuginstall', None)
         if handler is not None:
             problems += handler(ui, fm)
 
     fm.condwrite(not problems, b'', _(b"no problems detected\n"))
     if not problems:
         fm.data(problems=problems)
     fm.condwrite(
         problems,
         b'problems',
         _(b"%d problems detected, please check your install!\n"),
         problems,
     )
     fm.end()
 
     return problems
 
 
 @command(b'debugknown', [], _(b'REPO ID...'), norepo=True)
 def debugknown(ui, repopath, *ids, **opts):
     """test whether node ids are known to a repo
 
     Every ID must be a full-length hex node id string. Returns a list of 0s
     and 1s indicating unknown/known.
     """
     opts = pycompat.byteskwargs(opts)
     repo = hg.peer(ui, opts, repopath)
     if not repo.capable(b'known'):
         raise error.Abort(b"known() not supported by target repository")
     flags = repo.known([bin(s) for s in ids])
     ui.write(b"%s\n" % (b"".join([f and b"1" or b"0" for f in flags])))
 
 
 @command(b'debuglabelcomplete', [], _(b'LABEL...'))
 def debuglabelcomplete(ui, repo, *args):
     '''backwards compatibility with old bash completion scripts (DEPRECATED)'''
     debugnamecomplete(ui, repo, *args)
 
 
 @command(
     b'debuglocks',
     [
         (b'L', b'force-lock', None, _(b'free the store lock (DANGEROUS)')),
         (
             b'W',
             b'force-wlock',
             None,
             _(b'free the working state lock (DANGEROUS)'),
         ),
         (b's', b'set-lock', None, _(b'set the store lock until stopped')),
         (
             b'S',
             b'set-wlock',
             None,
             _(b'set the working state lock until stopped'),
         ),
     ],
     _(b'[OPTION]...'),
 )
 def debuglocks(ui, repo, **opts):
     """show or modify state of locks
 
     By default, this command will show which locks are held. This
     includes the user and process holding the lock, the amount of time
     the lock has been held, and the machine name where the process is
     running if it's not local.
 
     Locks protect the integrity of Mercurial's data, so should be
     treated with care. System crashes or other interruptions may cause
     locks to not be properly released, though Mercurial will usually
     detect and remove such stale locks automatically.
 
     However, detecting stale locks may not always be possible (for
     instance, on a shared filesystem). Removing locks may also be
     blocked by filesystem permissions.
 
     Setting a lock will prevent other commands from changing the data.
     The command will wait until an interruption (SIGINT, SIGTERM, ...) occurs.
     The set locks are removed when the command exits.
 
     Returns 0 if no locks are held.
 
     """
 
     if opts.get('force_lock'):
         repo.svfs.unlink(b'lock')
     if opts.get('force_wlock'):
         repo.vfs.unlink(b'wlock')
     if opts.get('force_lock') or opts.get('force_wlock'):
         return 0
 
     locks = []
     try:
         if opts.get('set_wlock'):
             try:
                 locks.append(repo.wlock(False))
             except error.LockHeld:
                 raise error.Abort(_(b'wlock is already held'))
         if opts.get('set_lock'):
             try:
                 locks.append(repo.lock(False))
             except error.LockHeld:
                 raise error.Abort(_(b'lock is already held'))
         if len(locks):
             ui.promptchoice(_(b"ready to release the lock (y)? $$ &Yes"))
             return 0
     finally:
         release(*locks)
 
     now = time.time()
     held = 0
 
     def report(vfs, name, method):
         # this causes stale locks to get reaped for more accurate reporting
         try:
             l = method(False)
         except error.LockHeld:
             l = None
 
         if l:
             l.release()
         else:
             try:
                 st = vfs.lstat(name)
                 age = now - st[stat.ST_MTIME]
                 user = util.username(st.st_uid)
                 locker = vfs.readlock(name)
                 if b":" in locker:
                     host, pid = locker.split(b':')
                     if host == socket.gethostname():
                         locker = b'user %s, process %s' % (user or b'None', pid)
                     else:
                         locker = b'user %s, process %s, host %s' % (
                             user or b'None',
                             pid,
                             host,
                         )
                 ui.writenoi18n(b"%-6s %s (%ds)\n" % (name + b":", locker, age))
                 return 1
             except OSError as e:
                 if e.errno != errno.ENOENT:
                     raise
 
         ui.writenoi18n(b"%-6s free\n" % (name + b":"))
         return 0
 
     held += report(repo.svfs, b"lock", repo.lock)
     held += report(repo.vfs, b"wlock", repo.wlock)
 
     return held
 
 
 @command(
     b'debugmanifestfulltextcache',
     [
         (b'', b'clear', False, _(b'clear the cache')),
         (
             b'a',
             b'add',
             [],
             _(b'add the given manifest nodes to the cache'),
             _(b'NODE'),
         ),
     ],
     b'',
 )
 def debugmanifestfulltextcache(ui, repo, add=(), **opts):
     """show, clear or amend the contents of the manifest fulltext cache"""
 
     def getcache():
         r = repo.manifestlog.getstorage(b'')
         try:
             return r._fulltextcache
         except AttributeError:
             msg = _(
                 b"Current revlog implementation doesn't appear to have a "
                 b"manifest fulltext cache\n"
             )
             raise error.Abort(msg)
 
     if opts.get('clear'):
         with repo.wlock():
             cache = getcache()
             cache.clear(clear_persisted_data=True)
             return
 
     if add:
         with repo.wlock():
             m = repo.manifestlog
             store = m.getstorage(b'')
             for n in add:
                 try:
                     manifest = m[store.lookup(n)]
                 except error.LookupError as e:
                     raise error.Abort(e, hint=b"Check your manifest node id")
                 manifest.read()  # stores revisision in cache too
             return
 
     cache = getcache()
     if not len(cache):
         ui.write(_(b'cache empty\n'))
     else:
         ui.write(
             _(
                 b'cache contains %d manifest entries, in order of most to '
                 b'least recent:\n'
             )
             % (len(cache),)
         )
         totalsize = 0
         for nodeid in cache:
             # Use cache.get to not update the LRU order
             data = cache.peek(nodeid)
             size = len(data)
             totalsize += size + 24  # 20 bytes nodeid, 4 bytes size
             ui.write(
                 _(b'id: %s, size %s\n') % (hex(nodeid), util.bytecount(size))
             )
         ondisk = cache._opener.stat(b'manifestfulltextcache').st_size
         ui.write(
             _(b'total cache data size %s, on-disk %s\n')
             % (util.bytecount(totalsize), util.bytecount(ondisk))
         )
 
 
 @command(b'debugmergestate', [] + cmdutil.templateopts, b'')
 def debugmergestate(ui, repo, *args, **opts):
     """print merge state
 
     Use --verbose to print out information about whether v1 or v2 merge state
     was chosen."""
 
     if ui.verbose:
         ms = mergestatemod.mergestate(repo)
 
         # sort so that reasonable information is on top
         v1records = ms._readrecordsv1()
         v2records = ms._readrecordsv2()
 
         if not v1records and not v2records:
             pass
         elif not v2records:
             ui.writenoi18n(b'no version 2 merge state\n')
         elif ms._v1v2match(v1records, v2records):
             ui.writenoi18n(b'v1 and v2 states match: using v2\n')
         else:
             ui.writenoi18n(b'v1 and v2 states mismatch: using v1\n')
 
     opts = pycompat.byteskwargs(opts)
     if not opts[b'template']:
         opts[b'template'] = (
             b'{if(commits, "", "no merge state found\n")}'
             b'{commits % "{name}{if(label, " ({label})")}: {node}\n"}'
             b'{files % "file: {path} (state \\"{state}\\")\n'
             b'{if(local_path, "'
             b'  local path: {local_path} (hash {local_key}, flags \\"{local_flags}\\")\n'
             b'  ancestor path: {ancestor_path} (node {ancestor_node})\n'
             b'  other path: {other_path} (node {other_node})\n'
             b'")}'
             b'{if(rename_side, "'
             b'  rename side: {rename_side}\n'
             b'  renamed path: {renamed_path}\n'
             b'")}'
             b'{extras % "  extra: {key} = {value}\n"}'
             b'"}'
             b'{extras % "extra: {file} ({key} = {value})\n"}'
         )
 
     ms = mergestatemod.mergestate.read(repo)
 
     fm = ui.formatter(b'debugmergestate', opts)
     fm.startitem()
 
     fm_commits = fm.nested(b'commits')
     if ms.active():
         for name, node, label_index in (
             (b'local', ms.local, 0),
             (b'other', ms.other, 1),
         ):
             fm_commits.startitem()
             fm_commits.data(name=name)
             fm_commits.data(node=hex(node))
             if ms._labels and len(ms._labels) > label_index:
                 fm_commits.data(label=ms._labels[label_index])
     fm_commits.end()
 
     fm_files = fm.nested(b'files')
     if ms.active():
         for f in ms:
             fm_files.startitem()
             fm_files.data(path=f)
             state = ms._state[f]
             fm_files.data(state=state[0])
             if state[0] in (
                 mergestatemod.MERGE_RECORD_UNRESOLVED,
                 mergestatemod.MERGE_RECORD_RESOLVED,
             ):
                 fm_files.data(local_key=state[1])
                 fm_files.data(local_path=state[2])
                 fm_files.data(ancestor_path=state[3])
                 fm_files.data(ancestor_node=state[4])
                 fm_files.data(other_path=state[5])
                 fm_files.data(other_node=state[6])
                 fm_files.data(local_flags=state[7])
             elif state[0] in (
                 mergestatemod.MERGE_RECORD_UNRESOLVED_PATH,
                 mergestatemod.MERGE_RECORD_RESOLVED_PATH,
             ):
                 fm_files.data(renamed_path=state[1])
                 fm_files.data(rename_side=state[2])
             fm_extras = fm_files.nested(b'extras')
             for k, v in sorted(ms.extras(f).items()):
                 fm_extras.startitem()
                 fm_extras.data(key=k)
                 fm_extras.data(value=v)
             fm_extras.end()
 
     fm_files.end()
 
     fm_extras = fm.nested(b'extras')
     for f, d in sorted(pycompat.iteritems(ms.allextras())):
         if f in ms:
             # If file is in mergestate, we have already processed it's extras
             continue
         for k, v in pycompat.iteritems(d):
             fm_extras.startitem()
             fm_extras.data(file=f)
             fm_extras.data(key=k)
             fm_extras.data(value=v)
     fm_extras.end()
 
     fm.end()
 
 
 @command(b'debugnamecomplete', [], _(b'NAME...'))
 def debugnamecomplete(ui, repo, *args):
     '''complete "names" - tags, open branch names, bookmark names'''
 
     names = set()
     # since we previously only listed open branches, we will handle that
     # specially (after this for loop)
     for name, ns in pycompat.iteritems(repo.names):
         if name != b'branches':
             names.update(ns.listnames(repo))
     names.update(
         tag
         for (tag, heads, tip, closed) in repo.branchmap().iterbranches()
         if not closed
     )
     completions = set()
     if not args:
         args = [b'']
     for a in args:
         completions.update(n for n in names if n.startswith(a))
     ui.write(b'\n'.join(sorted(completions)))
     ui.write(b'\n')
 
 
 @command(
     b'debugnodemap',
     [
         (
             b'',
             b'dump-new',
             False,
             _(b'write a (new) persistent binary nodemap on stdin'),
         ),
         (b'', b'dump-disk', False, _(b'dump on-disk data on stdin')),
         (
             b'',
             b'check',
             False,
             _(b'check that the data on disk data are correct.'),
         ),
         (
             b'',
             b'metadata',
             False,
             _(b'display the on disk meta data for the nodemap'),
         ),
     ],
 )
 def debugnodemap(ui, repo, **opts):
     """write and inspect on disk nodemap"""
     if opts['dump_new']:
         unfi = repo.unfiltered()
         cl = unfi.changelog
         if util.safehasattr(cl.index, "nodemap_data_all"):
             data = cl.index.nodemap_data_all()
         else:
             data = nodemap.persistent_data(cl.index)
         ui.write(data)
     elif opts['dump_disk']:
         unfi = repo.unfiltered()
         cl = unfi.changelog
         nm_data = nodemap.persisted_data(cl)
         if nm_data is not None:
             docket, data = nm_data
             ui.write(data[:])
     elif opts['check']:
         unfi = repo.unfiltered()
         cl = unfi.changelog
         nm_data = nodemap.persisted_data(cl)
         if nm_data is not None:
             docket, data = nm_data
             return nodemap.check_data(ui, cl.index, data)
     elif opts['metadata']:
         unfi = repo.unfiltered()
         cl = unfi.changelog
         nm_data = nodemap.persisted_data(cl)
         if nm_data is not None:
             docket, data = nm_data
             ui.write((b"uid: %s\n") % docket.uid)
             ui.write((b"tip-rev: %d\n") % docket.tip_rev)
             ui.write((b"tip-node: %s\n") % hex(docket.tip_node))
             ui.write((b"data-length: %d\n") % docket.data_length)
             ui.write((b"data-unused: %d\n") % docket.data_unused)
             unused_perc = docket.data_unused * 100.0 / docket.data_length
             ui.write((b"data-unused: %2.3f%%\n") % unused_perc)
 
 
 @command(
     b'debugobsolete',
     [
         (b'', b'flags', 0, _(b'markers flag')),
         (
             b'',
             b'record-parents',
             False,
             _(b'record parent information for the precursor'),
         ),
         (b'r', b'rev', [], _(b'display markers relevant to REV')),
         (
             b'',
             b'exclusive',
             False,
             _(b'restrict display to markers only relevant to REV'),
         ),
         (b'', b'index', False, _(b'display index of the marker')),
         (b'', b'delete', [], _(b'delete markers specified by indices')),
     ]
     + cmdutil.commitopts2
     + cmdutil.formatteropts,
     _(b'[OBSOLETED [REPLACEMENT ...]]'),
 )
 def debugobsolete(ui, repo, precursor=None, *successors, **opts):
     """create arbitrary obsolete marker
 
     With no arguments, displays the list of obsolescence markers."""
 
     opts = pycompat.byteskwargs(opts)
 
     def parsenodeid(s):
         try:
             # We do not use revsingle/revrange functions here to accept
             # arbitrary node identifiers, possibly not present in the
             # local repository.
             n = bin(s)
             if len(n) != len(nullid):
                 raise TypeError()
             return n
         except TypeError:
             raise error.InputError(
                 b'changeset references must be full hexadecimal '
                 b'node identifiers'
             )
 
     if opts.get(b'delete'):
         indices = []
         for v in opts.get(b'delete'):
             try:
                 indices.append(int(v))
             except ValueError:
                 raise error.InputError(
                     _(b'invalid index value: %r') % v,
                     hint=_(b'use integers for indices'),
                 )
 
         if repo.currenttransaction():
             raise error.Abort(
                 _(b'cannot delete obsmarkers in the middle of transaction.')
             )
 
         with repo.lock():
             n = repair.deleteobsmarkers(repo.obsstore, indices)
             ui.write(_(b'deleted %i obsolescence markers\n') % n)
 
         return
 
     if precursor is not None:
         if opts[b'rev']:
             raise error.InputError(
                 b'cannot select revision when creating marker'
             )
         metadata = {}
         metadata[b'user'] = encoding.fromlocal(opts[b'user'] or ui.username())
         succs = tuple(parsenodeid(succ) for succ in successors)
         l = repo.lock()
         try:
             tr = repo.transaction(b'debugobsolete')
             try:
                 date = opts.get(b'date')
                 if date:
                     date = dateutil.parsedate(date)
                 else:
                     date = None
                 prec = parsenodeid(precursor)
                 parents = None
                 if opts[b'record_parents']:
                     if prec not in repo.unfiltered():
                         raise error.Abort(
                             b'cannot used --record-parents on '
                             b'unknown changesets'
                         )
                     parents = repo.unfiltered()[prec].parents()
                     parents = tuple(p.node() for p in parents)
                 repo.obsstore.create(
                     tr,
                     prec,
                     succs,
                     opts[b'flags'],
                     parents=parents,
                     date=date,
                     metadata=metadata,
                     ui=ui,
                 )
                 tr.close()
             except ValueError as exc:
                 raise error.Abort(
                     _(b'bad obsmarker input: %s') % pycompat.bytestr(exc)
                 )
             finally:
                 tr.release()
         finally:
             l.release()
     else:
         if opts[b'rev']:
             revs = scmutil.revrange(repo, opts[b'rev'])
             nodes = [repo[r].node() for r in revs]
             markers = list(
                 obsutil.getmarkers(
                     repo, nodes=nodes, exclusive=opts[b'exclusive']
                 )
             )
             markers.sort(key=lambda x: x._data)
         else:
             markers = obsutil.getmarkers(repo)
 
         markerstoiter = markers
         isrelevant = lambda m: True
         if opts.get(b'rev') and opts.get(b'index'):
             markerstoiter = obsutil.getmarkers(repo)
             markerset = set(markers)
             isrelevant = lambda m: m in markerset
 
         fm = ui.formatter(b'debugobsolete', opts)
         for i, m in enumerate(markerstoiter):
             if not isrelevant(m):
                 # marker can be irrelevant when we're iterating over a set
                 # of markers (markerstoiter) which is bigger than the set
                 # of markers we want to display (markers)
                 # this can happen if both --index and --rev options are
                 # provided and thus we need to iterate over all of the markers
                 # to get the correct indices, but only display the ones that
                 # are relevant to --rev value
                 continue
             fm.startitem()
             ind = i if opts.get(b'index') else None
             cmdutil.showmarker(fm, m, index=ind)
         fm.end()
 
 
 @command(
     b'debugp1copies',
     [(b'r', b'rev', b'', _(b'revision to debug'), _(b'REV'))],
     _(b'[-r REV]'),
 )
 def debugp1copies(ui, repo, **opts):
     """dump copy information compared to p1"""
 
     opts = pycompat.byteskwargs(opts)
     ctx = scmutil.revsingle(repo, opts.get(b'rev'), default=None)
     for dst, src in ctx.p1copies().items():
         ui.write(b'%s -> %s\n' % (src, dst))
 
 
 @command(
     b'debugp2copies',
     [(b'r', b'rev', b'', _(b'revision to debug'), _(b'REV'))],
     _(b'[-r REV]'),
 )
 def debugp1copies(ui, repo, **opts):
     """dump copy information compared to p2"""
 
     opts = pycompat.byteskwargs(opts)
     ctx = scmutil.revsingle(repo, opts.get(b'rev'), default=None)
     for dst, src in ctx.p2copies().items():
         ui.write(b'%s -> %s\n' % (src, dst))
 
 
 @command(
     b'debugpathcomplete',
     [
         (b'f', b'full', None, _(b'complete an entire path')),
         (b'n', b'normal', None, _(b'show only normal files')),
         (b'a', b'added', None, _(b'show only added files')),
         (b'r', b'removed', None, _(b'show only removed files')),
     ],
     _(b'FILESPEC...'),
 )
 def debugpathcomplete(ui, repo, *specs, **opts):
     """complete part or all of a tracked path
 
     This command supports shells that offer path name completion. It
     currently completes only files already known to the dirstate.
 
     Completion extends only to the next path segment unless
     --full is specified, in which case entire paths are used."""
 
     def complete(path, acceptable):
         dirstate = repo.dirstate
         spec = os.path.normpath(os.path.join(encoding.getcwd(), path))
         rootdir = repo.root + pycompat.ossep
         if spec != repo.root and not spec.startswith(rootdir):
             return [], []
         if os.path.isdir(spec):
             spec += b'/'
         spec = spec[len(rootdir) :]
         fixpaths = pycompat.ossep != b'/'
         if fixpaths:
             spec = spec.replace(pycompat.ossep, b'/')
         speclen = len(spec)
         fullpaths = opts['full']
         files, dirs = set(), set()
         adddir, addfile = dirs.add, files.add
         for f, st in pycompat.iteritems(dirstate):
             if f.startswith(spec) and st[0] in acceptable:
                 if fixpaths:
                     f = f.replace(b'/', pycompat.ossep)
                 if fullpaths:
                     addfile(f)
                     continue
                 s = f.find(pycompat.ossep, speclen)
                 if s >= 0:
                     adddir(f[:s])
                 else:
                     addfile(f)
         return files, dirs
 
     acceptable = b''
     if opts['normal']:
         acceptable += b'nm'
     if opts['added']:
         acceptable += b'a'
     if opts['removed']:
         acceptable += b'r'
     cwd = repo.getcwd()
     if not specs:
         specs = [b'.']
 
     files, dirs = set(), set()
     for spec in specs:
         f, d = complete(spec, acceptable or b'nmar')
         files.update(f)
         dirs.update(d)
     files.update(dirs)
     ui.write(b'\n'.join(repo.pathto(p, cwd) for p in sorted(files)))
     ui.write(b'\n')
 
 
 @command(
     b'debugpathcopies',
     cmdutil.walkopts,
     b'hg debugpathcopies REV1 REV2 [FILE]',
     inferrepo=True,
 )
 def debugpathcopies(ui, repo, rev1, rev2, *pats, **opts):
     """show copies between two revisions"""
     ctx1 = scmutil.revsingle(repo, rev1)
     ctx2 = scmutil.revsingle(repo, rev2)
     m = scmutil.match(ctx1, pats, opts)
     for dst, src in sorted(copies.pathcopies(ctx1, ctx2, m).items()):
         ui.write(b'%s -> %s\n' % (src, dst))
 
 
 @command(b'debugpeer', [], _(b'PATH'), norepo=True)
 def debugpeer(ui, path):
     """establish a connection to a peer repository"""
     # Always enable peer request logging. Requires --debug to display
     # though.
     overrides = {
         (b'devel', b'debug.peer-request'): True,
     }
 
     with ui.configoverride(overrides):
         peer = hg.peer(ui, {}, path)
 
         local = peer.local() is not None
         canpush = peer.canpush()
 
         ui.write(_(b'url: %s\n') % peer.url())
         ui.write(_(b'local: %s\n') % (_(b'yes') if local else _(b'no')))
         ui.write(_(b'pushable: %s\n') % (_(b'yes') if canpush else _(b'no')))
 
 
 @command(
     b'debugpickmergetool',
     [
         (b'r', b'rev', b'', _(b'check for files in this revision'), _(b'REV')),
         (b'', b'changedelete', None, _(b'emulate merging change and delete')),
     ]
     + cmdutil.walkopts
     + cmdutil.mergetoolopts,
     _(b'[PATTERN]...'),
     inferrepo=True,
 )
 def debugpickmergetool(ui, repo, *pats, **opts):
     """examine which merge tool is chosen for specified file
 
     As described in :hg:`help merge-tools`, Mercurial examines
     configurations below in this order to decide which merge tool is
     chosen for specified file.
 
     1. ``--tool`` option
     2. ``HGMERGE`` environment variable
     3. configurations in ``merge-patterns`` section
     4. configuration of ``ui.merge``
     5. configurations in ``merge-tools`` section
     6. ``hgmerge`` tool (for historical reason only)
     7. default tool for fallback (``:merge`` or ``:prompt``)
 
     This command writes out examination result in the style below::
 
         FILE = MERGETOOL
 
     By default, all files known in the first parent context of the
     working directory are examined. Use file patterns and/or -I/-X
     options to limit target files. -r/--rev is also useful to examine
     files in another context without actual updating to it.
 
     With --debug, this command shows warning messages while matching
     against ``merge-patterns`` and so on, too. It is recommended to
     use this option with explicit file patterns and/or -I/-X options,
     because this option increases amount of output per file according
     to configurations in hgrc.
 
     With -v/--verbose, this command shows configurations below at
     first (only if specified).
 
     - ``--tool`` option
     - ``HGMERGE`` environment variable
     - configuration of ``ui.merge``
 
     If merge tool is chosen before matching against
     ``merge-patterns``, this command can't show any helpful
     information, even with --debug. In such case, information above is
     useful to know why a merge tool is chosen.
     """
     opts = pycompat.byteskwargs(opts)
     overrides = {}
     if opts[b'tool']:
         overrides[(b'ui', b'forcemerge')] = opts[b'tool']
         ui.notenoi18n(b'with --tool %r\n' % (pycompat.bytestr(opts[b'tool'])))
 
     with ui.configoverride(overrides, b'debugmergepatterns'):
         hgmerge = encoding.environ.get(b"HGMERGE")
         if hgmerge is not None:
             ui.notenoi18n(b'with HGMERGE=%r\n' % (pycompat.bytestr(hgmerge)))
         uimerge = ui.config(b"ui", b"merge")
         if uimerge:
             ui.notenoi18n(b'with ui.merge=%r\n' % (pycompat.bytestr(uimerge)))
 
         ctx = scmutil.revsingle(repo, opts.get(b'rev'))
         m = scmutil.match(ctx, pats, opts)
         changedelete = opts[b'changedelete']
         for path in ctx.walk(m):
             fctx = ctx[path]
             try:
                 if not ui.debugflag:
                     ui.pushbuffer(error=True)
                 tool, toolpath = filemerge._picktool(
                     repo,
                     ui,
                     path,
                     fctx.isbinary(),
                     b'l' in fctx.flags(),
                     changedelete,
                 )
             finally:
                 if not ui.debugflag:
                     ui.popbuffer()
             ui.write(b'%s = %s\n' % (path, tool))
 
 
 @command(b'debugpushkey', [], _(b'REPO NAMESPACE [KEY OLD NEW]'), norepo=True)
 def debugpushkey(ui, repopath, namespace, *keyinfo, **opts):
     """access the pushkey key/value protocol
 
     With two args, list the keys in the given namespace.
 
     With five args, set a key to new if it currently is set to old.
     Reports success or failure.
     """
 
     target = hg.peer(ui, {}, repopath)
     if keyinfo:
         key, old, new = keyinfo
         with target.commandexecutor() as e:
             r = e.callcommand(
                 b'pushkey',
                 {
                     b'namespace': namespace,
                     b'key': key,
                     b'old': old,
                     b'new': new,
                 },
             ).result()
 
         ui.status(pycompat.bytestr(r) + b'\n')
         return not r
     else:
         for k, v in sorted(pycompat.iteritems(target.listkeys(namespace))):
             ui.write(
                 b"%s\t%s\n" % (stringutil.escapestr(k), stringutil.escapestr(v))
             )
 
 
 @command(b'debugpvec', [], _(b'A B'))
 def debugpvec(ui, repo, a, b=None):
     ca = scmutil.revsingle(repo, a)
     cb = scmutil.revsingle(repo, b)
     pa = pvec.ctxpvec(ca)
     pb = pvec.ctxpvec(cb)
     if pa == pb:
         rel = b"="
     elif pa > pb:
         rel = b">"
     elif pa < pb:
         rel = b"<"
     elif pa | pb:
         rel = b"|"
     ui.write(_(b"a: %s\n") % pa)
     ui.write(_(b"b: %s\n") % pb)
     ui.write(_(b"depth(a): %d depth(b): %d\n") % (pa._depth, pb._depth))
     ui.write(
         _(b"delta: %d hdist: %d distance: %d relation: %s\n")
         % (
             abs(pa._depth - pb._depth),
             pvec._hamming(pa._vec, pb._vec),
             pa.distance(pb),
             rel,
         )
     )
 
 
 @command(
     b'debugrebuilddirstate|debugrebuildstate',
     [
         (b'r', b'rev', b'', _(b'revision to rebuild to'), _(b'REV')),
         (
             b'',
             b'minimal',
             None,
             _(
                 b'only rebuild files that are inconsistent with '
                 b'the working copy parent'
             ),
         ),
     ],
     _(b'[-r REV]'),
 )
 def debugrebuilddirstate(ui, repo, rev, **opts):
     """rebuild the dirstate as it would look like for the given revision
 
     If no revision is specified the first current parent will be used.
 
     The dirstate will be set to the files of the given revision.
     The actual working directory content or existing dirstate
     information such as adds or removes is not considered.
 
     ``minimal`` will only rebuild the dirstate status for files that claim to be
     tracked but are not in the parent manifest, or that exist in the parent
     manifest but are not in the dirstate. It will not change adds, removes, or
     modified files that are in the working copy parent.
 
     One use of this command is to make the next :hg:`status` invocation
     check the actual file content.
     """
     ctx = scmutil.revsingle(repo, rev)
     with repo.wlock():
         dirstate = repo.dirstate
         changedfiles = None
         # See command doc for what minimal does.
         if opts.get('minimal'):
             manifestfiles = set(ctx.manifest().keys())
             dirstatefiles = set(dirstate)
             manifestonly = manifestfiles - dirstatefiles
             dsonly = dirstatefiles - manifestfiles
             dsnotadded = {f for f in dsonly if dirstate[f] != b'a'}
             changedfiles = manifestonly | dsnotadded
 
         dirstate.rebuild(ctx.node(), ctx.manifest(), changedfiles)
 
 
 @command(b'debugrebuildfncache', [], b'')
 def debugrebuildfncache(ui, repo):
     """rebuild the fncache file"""
     repair.rebuildfncache(ui, repo)
 
 
 @command(
     b'debugrename',
     [(b'r', b'rev', b'', _(b'revision to debug'), _(b'REV'))],
     _(b'[-r REV] [FILE]...'),
 )
 def debugrename(ui, repo, *pats, **opts):
     """dump rename information"""
 
     opts = pycompat.byteskwargs(opts)
     ctx = scmutil.revsingle(repo, opts.get(b'rev'))
     m = scmutil.match(ctx, pats, opts)
     for abs in ctx.walk(m):
         fctx = ctx[abs]
         o = fctx.filelog().renamed(fctx.filenode())
         rel = repo.pathto(abs)
         if o:
             ui.write(_(b"%s renamed from %s:%s\n") % (rel, o[0], hex(o[1])))
         else:
             ui.write(_(b"%s not renamed\n") % rel)
 
 
 @command(b'debugrequires|debugrequirements', [], b'')
 def debugrequirements(ui, repo):
     """ print the current repo requirements """
     for r in sorted(repo.requirements):
         ui.write(b"%s\n" % r)
 
 
 @command(
     b'debugrevlog',
     cmdutil.debugrevlogopts + [(b'd', b'dump', False, _(b'dump index data'))],
     _(b'-c|-m|FILE'),
     optionalrepo=True,
 )
 def debugrevlog(ui, repo, file_=None, **opts):
     """show data and statistics about a revlog"""
     opts = pycompat.byteskwargs(opts)
     r = cmdutil.openrevlog(repo, b'debugrevlog', file_, opts)
 
     if opts.get(b"dump"):
         numrevs = len(r)
         ui.write(
             (
                 b"# rev p1rev p2rev start   end deltastart base   p1   p2"
                 b" rawsize totalsize compression heads chainlen\n"
             )
         )
         ts = 0
         heads = set()
 
         for rev in pycompat.xrange(numrevs):
             dbase = r.deltaparent(rev)
             if dbase == -1:
                 dbase = rev
             cbase = r.chainbase(rev)
             clen = r.chainlen(rev)
             p1, p2 = r.parentrevs(rev)
             rs = r.rawsize(rev)
             ts = ts + rs
             heads -= set(r.parentrevs(rev))
             heads.add(rev)
             try:
                 compression = ts / r.end(rev)
             except ZeroDivisionError:
                 compression = 0
             ui.write(
                 b"%5d %5d %5d %5d %5d %10d %4d %4d %4d %7d %9d "
                 b"%11d %5d %8d\n"
                 % (
                     rev,
                     p1,
                     p2,
                     r.start(rev),
                     r.end(rev),
                     r.start(dbase),
                     r.start(cbase),
                     r.start(p1),
                     r.start(p2),
                     rs,
                     ts,
                     compression,
                     len(heads),
                     clen,
                 )
             )
         return 0
 
     v = r.version
     format = v & 0xFFFF
     flags = []
     gdelta = False
     if v & revlog.FLAG_INLINE_DATA:
         flags.append(b'inline')
     if v & revlog.FLAG_GENERALDELTA:
         gdelta = True
         flags.append(b'generaldelta')
     if not flags:
         flags = [b'(none)']
 
     ### tracks merge vs single parent
     nummerges = 0
 
     ### tracks ways the "delta" are build
     # nodelta
     numempty = 0
     numemptytext = 0
     numemptydelta = 0
     # full file content
     numfull = 0
     # intermediate snapshot against a prior snapshot
     numsemi = 0
     # snapshot count per depth
     numsnapdepth = collections.defaultdict(lambda: 0)
     # delta against previous revision
     numprev = 0
     # delta against first or second parent (not prev)
     nump1 = 0
     nump2 = 0
     # delta against neither prev nor parents
     numother = 0
     # delta against prev that are also first or second parent
     # (details of `numprev`)
     nump1prev = 0
     nump2prev = 0
 
     # data about delta chain of each revs
     chainlengths = []
     chainbases = []
     chainspans = []
 
     # data about each revision
     datasize = [None, 0, 0]
     fullsize = [None, 0, 0]
     semisize = [None, 0, 0]
     # snapshot count per depth
     snapsizedepth = collections.defaultdict(lambda: [None, 0, 0])
     deltasize = [None, 0, 0]
     chunktypecounts = {}
     chunktypesizes = {}
 
     def addsize(size, l):
         if l[0] is None or size < l[0]:
             l[0] = size
         if size > l[1]:
             l[1] = size
         l[2] += size
 
     numrevs = len(r)
     for rev in pycompat.xrange(numrevs):
         p1, p2 = r.parentrevs(rev)
         delta = r.deltaparent(rev)
         if format > 0:
             addsize(r.rawsize(rev), datasize)
         if p2 != nullrev:
             nummerges += 1
         size = r.length(rev)
         if delta == nullrev:
             chainlengths.append(0)
             chainbases.append(r.start(rev))
             chainspans.append(size)
             if size == 0:
                 numempty += 1
                 numemptytext += 1
             else:
                 numfull += 1
                 numsnapdepth[0] += 1
                 addsize(size, fullsize)
                 addsize(size, snapsizedepth[0])
         else:
             chainlengths.append(chainlengths[delta] + 1)
             baseaddr = chainbases[delta]
             revaddr = r.start(rev)
             chainbases.append(baseaddr)
             chainspans.append((revaddr - baseaddr) + size)
             if size == 0:
                 numempty += 1
                 numemptydelta += 1
             elif r.issnapshot(rev):
                 addsize(size, semisize)
                 numsemi += 1
                 depth = r.snapshotdepth(rev)
                 numsnapdepth[depth] += 1
                 addsize(size, snapsizedepth[depth])
             else:
                 addsize(size, deltasize)
                 if delta == rev - 1:
                     numprev += 1
                     if delta == p1:
                         nump1prev += 1
                     elif delta == p2:
                         nump2prev += 1
                 elif delta == p1:
                     nump1 += 1
                 elif delta == p2:
                     nump2 += 1
                 elif delta != nullrev:
                     numother += 1
 
         # Obtain data on the raw chunks in the revlog.
         if util.safehasattr(r, b'_getsegmentforrevs'):
             segment = r._getsegmentforrevs(rev, rev)[1]
         else:
             segment = r._revlog._getsegmentforrevs(rev, rev)[1]
         if segment:
             chunktype = bytes(segment[0:1])
         else:
             chunktype = b'empty'
 
         if chunktype not in chunktypecounts:
             chunktypecounts[chunktype] = 0
             chunktypesizes[chunktype] = 0
 
         chunktypecounts[chunktype] += 1
         chunktypesizes[chunktype] += size
 
     # Adjust size min value for empty cases
     for size in (datasize, fullsize, semisize, deltasize):
         if size[0] is None:
             size[0] = 0
 
     numdeltas = numrevs - numfull - numempty - numsemi
     numoprev = numprev - nump1prev - nump2prev
     totalrawsize = datasize[2]
     datasize[2] /= numrevs
     fulltotal = fullsize[2]
     if numfull == 0:
         fullsize[2] = 0
     else:
         fullsize[2] /= numfull
     semitotal = semisize[2]
     snaptotal = {}
     if numsemi > 0:
         semisize[2] /= numsemi
     for depth in snapsizedepth:
         snaptotal[depth] = snapsizedepth[depth][2]
         snapsizedepth[depth][2] /= numsnapdepth[depth]
 
     deltatotal = deltasize[2]
     if numdeltas > 0:
         deltasize[2] /= numdeltas
     totalsize = fulltotal + semitotal + deltatotal
     avgchainlen = sum(chainlengths) / numrevs
     maxchainlen = max(chainlengths)
     maxchainspan = max(chainspans)
     compratio = 1
     if totalsize:
         compratio = totalrawsize / totalsize
 
     basedfmtstr = b'%%%dd\n'
     basepcfmtstr = b'%%%dd %s(%%5.2f%%%%)\n'
 
     def dfmtstr(max):
         return basedfmtstr % len(str(max))
 
     def pcfmtstr(max, padding=0):
         return basepcfmtstr % (len(str(max)), b' ' * padding)
 
     def pcfmt(value, total):
         if total:
             return (value, 100 * float(value) / total)
         else:
             return value, 100.0
 
     ui.writenoi18n(b'format : %d\n' % format)
     ui.writenoi18n(b'flags  : %s\n' % b', '.join(flags))
 
     ui.write(b'\n')
     fmt = pcfmtstr(totalsize)
     fmt2 = dfmtstr(totalsize)
     ui.writenoi18n(b'revisions     : ' + fmt2 % numrevs)
     ui.writenoi18n(b'    merges    : ' + fmt % pcfmt(nummerges, numrevs))
     ui.writenoi18n(
         b'    normal    : ' + fmt % pcfmt(numrevs - nummerges, numrevs)
     )
     ui.writenoi18n(b'revisions     : ' + fmt2 % numrevs)
     ui.writenoi18n(b'    empty     : ' + fmt % pcfmt(numempty, numrevs))
     ui.writenoi18n(
         b'                   text  : '
         + fmt % pcfmt(numemptytext, numemptytext + numemptydelta)
     )
     ui.writenoi18n(
         b'                   delta : '
         + fmt % pcfmt(numemptydelta, numemptytext + numemptydelta)
     )
     ui.writenoi18n(
         b'    snapshot  : ' + fmt % pcfmt(numfull + numsemi, numrevs)
     )
     for depth in sorted(numsnapdepth):
         ui.write(
             (b'      lvl-%-3d :       ' % depth)
             + fmt % pcfmt(numsnapdepth[depth], numrevs)
         )
     ui.writenoi18n(b'    deltas    : ' + fmt % pcfmt(numdeltas, numrevs))
     ui.writenoi18n(b'revision size : ' + fmt2 % totalsize)
     ui.writenoi18n(
         b'    snapshot  : ' + fmt % pcfmt(fulltotal + semitotal, totalsize)
     )
     for depth in sorted(numsnapdepth):
         ui.write(
             (b'      lvl-%-3d :       ' % depth)
             + fmt % pcfmt(snaptotal[depth], totalsize)
         )
     ui.writenoi18n(b'    deltas    : ' + fmt % pcfmt(deltatotal, totalsize))
 
     def fmtchunktype(chunktype):
         if chunktype == b'empty':
             return b'    %s     : ' % chunktype
         elif chunktype in pycompat.bytestr(string.ascii_letters):
             return b'    0x%s (%s)  : ' % (hex(chunktype), chunktype)
         else:
             return b'    0x%s      : ' % hex(chunktype)
 
     ui.write(b'\n')
     ui.writenoi18n(b'chunks        : ' + fmt2 % numrevs)
     for chunktype in sorted(chunktypecounts):
         ui.write(fmtchunktype(chunktype))
         ui.write(fmt % pcfmt(chunktypecounts[chunktype], numrevs))
     ui.writenoi18n(b'chunks size   : ' + fmt2 % totalsize)
     for chunktype in sorted(chunktypecounts):
         ui.write(fmtchunktype(chunktype))
         ui.write(fmt % pcfmt(chunktypesizes[chunktype], totalsize))
 
     ui.write(b'\n')
     fmt = dfmtstr(max(avgchainlen, maxchainlen, maxchainspan, compratio))
     ui.writenoi18n(b'avg chain length  : ' + fmt % avgchainlen)
     ui.writenoi18n(b'max chain length  : ' + fmt % maxchainlen)
     ui.writenoi18n(b'max chain reach   : ' + fmt % maxchainspan)
     ui.writenoi18n(b'compression ratio : ' + fmt % compratio)
 
     if format > 0:
         ui.write(b'\n')
         ui.writenoi18n(
             b'uncompressed data size (min/max/avg) : %d / %d / %d\n'
             % tuple(datasize)
         )
     ui.writenoi18n(
         b'full revision size (min/max/avg)     : %d / %d / %d\n'
         % tuple(fullsize)
     )
     ui.writenoi18n(
         b'inter-snapshot size (min/max/avg)    : %d / %d / %d\n'
         % tuple(semisize)
     )
     for depth in sorted(snapsizedepth):
         if depth == 0:
             continue
         ui.writenoi18n(
             b'    level-%-3d (min/max/avg)          : %d / %d / %d\n'
             % ((depth,) + tuple(snapsizedepth[depth]))
         )
     ui.writenoi18n(
         b'delta size (min/max/avg)             : %d / %d / %d\n'
         % tuple(deltasize)
     )
 
     if numdeltas > 0:
         ui.write(b'\n')
         fmt = pcfmtstr(numdeltas)
         fmt2 = pcfmtstr(numdeltas, 4)
         ui.writenoi18n(
             b'deltas against prev  : ' + fmt % pcfmt(numprev, numdeltas)
         )
         if numprev > 0:
             ui.writenoi18n(
                 b'    where prev = p1  : ' + fmt2 % pcfmt(nump1prev, numprev)
             )
             ui.writenoi18n(
                 b'    where prev = p2  : ' + fmt2 % pcfmt(nump2prev, numprev)
             )
             ui.writenoi18n(
                 b'    other            : ' + fmt2 % pcfmt(numoprev, numprev)
             )
         if gdelta:
             ui.writenoi18n(
                 b'deltas against p1    : ' + fmt % pcfmt(nump1, numdeltas)
             )
             ui.writenoi18n(
                 b'deltas against p2    : ' + fmt % pcfmt(nump2, numdeltas)
             )
             ui.writenoi18n(
                 b'deltas against other : ' + fmt % pcfmt(numother, numdeltas)
             )
 
 
 @command(
     b'debugrevlogindex',
     cmdutil.debugrevlogopts
     + [(b'f', b'format', 0, _(b'revlog format'), _(b'FORMAT'))],
     _(b'[-f FORMAT] -c|-m|FILE'),
     optionalrepo=True,
 )
 def debugrevlogindex(ui, repo, file_=None, **opts):
     """dump the contents of a revlog index"""
     opts = pycompat.byteskwargs(opts)
     r = cmdutil.openrevlog(repo, b'debugrevlogindex', file_, opts)
     format = opts.get(b'format', 0)
     if format not in (0, 1):
         raise error.Abort(_(b"unknown format %d") % format)
 
     if ui.debugflag:
         shortfn = hex
     else:
         shortfn = short
 
     # There might not be anything in r, so have a sane default
     idlen = 12
     for i in r:
         idlen = len(shortfn(r.node(i)))
         break
 
     if format == 0:
         if ui.verbose:
             ui.writenoi18n(
                 b"   rev    offset  length linkrev %s %s p2\n"
                 % (b"nodeid".ljust(idlen), b"p1".ljust(idlen))
             )
         else:
             ui.writenoi18n(
                 b"   rev linkrev %s %s p2\n"
                 % (b"nodeid".ljust(idlen), b"p1".ljust(idlen))
             )
     elif format == 1:
         if ui.verbose:
             ui.writenoi18n(
                 (
                     b"   rev flag   offset   length     size   link     p1"
                     b"     p2 %s\n"
                 )
                 % b"nodeid".rjust(idlen)
             )
         else:
             ui.writenoi18n(
                 b"   rev flag     size   link     p1     p2 %s\n"
                 % b"nodeid".rjust(idlen)
             )
 
     for i in r:
         node = r.node(i)
         if format == 0:
             try:
                 pp = r.parents(node)
             except Exception:
                 pp = [nullid, nullid]
             if ui.verbose:
                 ui.write(
                     b"% 6d % 9d % 7d % 7d %s %s %s\n"
                     % (
                         i,
                         r.start(i),
                         r.length(i),
                         r.linkrev(i),
                         shortfn(node),
                         shortfn(pp[0]),
                         shortfn(pp[1]),
                     )
                 )
             else:
                 ui.write(
                     b"% 6d % 7d %s %s %s\n"
                     % (
                         i,
                         r.linkrev(i),
                         shortfn(node),
                         shortfn(pp[0]),
                         shortfn(pp[1]),
                     )
                 )
         elif format == 1:
             pr = r.parentrevs(i)
             if ui.verbose:
                 ui.write(
                     b"% 6d %04x % 8d % 8d % 8d % 6d % 6d % 6d %s\n"
                     % (
                         i,
                         r.flags(i),
                         r.start(i),
                         r.length(i),
                         r.rawsize(i),
                         r.linkrev(i),
                         pr[0],
                         pr[1],
                         shortfn(node),
                     )
                 )
             else:
                 ui.write(
                     b"% 6d %04x % 8d % 6d % 6d % 6d %s\n"
                     % (
                         i,
                         r.flags(i),
                         r.rawsize(i),
                         r.linkrev(i),
                         pr[0],
                         pr[1],
                         shortfn(node),
                     )
                 )
 
 
 @command(
     b'debugrevspec',
     [
         (
             b'',
             b'optimize',
             None,
             _(b'print parsed tree after optimizing (DEPRECATED)'),
         ),
         (
             b'',
             b'show-revs',
             True,
             _(b'print list of result revisions (default)'),
         ),
         (
             b's',
             b'show-set',
             None,
             _(b'print internal representation of result set'),
         ),
         (
             b'p',
             b'show-stage',
             [],
             _(b'print parsed tree at the given stage'),
             _(b'NAME'),
         ),
         (b'', b'no-optimized', False, _(b'evaluate tree without optimization')),
         (b'', b'verify-optimized', False, _(b'verify optimized result')),
     ],
     b'REVSPEC',
 )
 def debugrevspec(ui, repo, expr, **opts):
     """parse and apply a revision specification
 
     Use -p/--show-stage option to print the parsed tree at the given stages.
     Use -p all to print tree at every stage.
 
     Use --no-show-revs option with -s or -p to print only the set
     representation or the parsed tree respectively.
 
     Use --verify-optimized to compare the optimized result with the unoptimized
     one. Returns 1 if the optimized result differs.
     """
     opts = pycompat.byteskwargs(opts)
     aliases = ui.configitems(b'revsetalias')
     stages = [
         (b'parsed', lambda tree: tree),
         (
             b'expanded',
             lambda tree: revsetlang.expandaliases(tree, aliases, ui.warn),
         ),
         (b'concatenated', revsetlang.foldconcat),
         (b'analyzed', revsetlang.analyze),
         (b'optimized', revsetlang.optimize),
     ]
     if opts[b'no_optimized']:
         stages = stages[:-1]
     if opts[b'verify_optimized'] and opts[b'no_optimized']:
         raise error.Abort(
             _(b'cannot use --verify-optimized with --no-optimized')
         )
     stagenames = {n for n, f in stages}
 
     showalways = set()
     showchanged = set()
     if ui.verbose and not opts[b'show_stage']:
         # show parsed tree by --verbose (deprecated)
         showalways.add(b'parsed')
         showchanged.update([b'expanded', b'concatenated'])
         if opts[b'optimize']:
             showalways.add(b'optimized')
     if opts[b'show_stage'] and opts[b'optimize']:
         raise error.Abort(_(b'cannot use --optimize with --show-stage'))
     if opts[b'show_stage'] == [b'all']:
         showalways.update(stagenames)
     else:
         for n in opts[b'show_stage']:
             if n not in stagenames:
                 raise error.Abort(_(b'invalid stage name: %s') % n)
         showalways.update(opts[b'show_stage'])
 
     treebystage = {}
     printedtree = None
     tree = revsetlang.parse(expr, lookup=revset.lookupfn(repo))
     for n, f in stages:
         treebystage[n] = tree = f(tree)
         if n in showalways or (n in showchanged and tree != printedtree):
             if opts[b'show_stage'] or n != b'parsed':
                 ui.write(b"* %s:\n" % n)
             ui.write(revsetlang.prettyformat(tree), b"\n")
             printedtree = tree
 
     if opts[b'verify_optimized']:
         arevs = revset.makematcher(treebystage[b'analyzed'])(repo)
         brevs = revset.makematcher(treebystage[b'optimized'])(repo)
         if opts[b'show_set'] or (opts[b'show_set'] is None and ui.verbose):
             ui.writenoi18n(
                 b"* analyzed set:\n", stringutil.prettyrepr(arevs), b"\n"
             )
             ui.writenoi18n(
                 b"* optimized set:\n", stringutil.prettyrepr(brevs), b"\n"
             )
         arevs = list(arevs)
         brevs = list(brevs)
         if arevs == brevs:
             return 0
         ui.writenoi18n(b'--- analyzed\n', label=b'diff.file_a')
         ui.writenoi18n(b'+++ optimized\n', label=b'diff.file_b')
         sm = difflib.SequenceMatcher(None, arevs, brevs)
         for tag, alo, ahi, blo, bhi in sm.get_opcodes():
             if tag in ('delete', 'replace'):
                 for c in arevs[alo:ahi]:
                     ui.write(b'-%d\n' % c, label=b'diff.deleted')
             if tag in ('insert', 'replace'):
                 for c in brevs[blo:bhi]:
                     ui.write(b'+%d\n' % c, label=b'diff.inserted')
             if tag == 'equal':
                 for c in arevs[alo:ahi]:
                     ui.write(b' %d\n' % c)
         return 1
 
     func = revset.makematcher(tree)
     revs = func(repo)
     if opts[b'show_set'] or (opts[b'show_set'] is None and ui.verbose):
         ui.writenoi18n(b"* set:\n", stringutil.prettyrepr(revs), b"\n")
     if not opts[b'show_revs']:
         return
     for c in revs:
         ui.write(b"%d\n" % c)
 
 
 @command(
     b'debugserve',
     [
         (
             b'',
             b'sshstdio',
             False,
             _(b'run an SSH server bound to process handles'),
         ),
         (b'', b'logiofd', b'', _(b'file descriptor to log server I/O to')),
         (b'', b'logiofile', b'', _(b'file to log server I/O to')),
     ],
     b'',
 )
 def debugserve(ui, repo, **opts):
     """run a server with advanced settings
 
     This command is similar to :hg:`serve`. It exists partially as a
     workaround to the fact that ``hg serve --stdio`` must have specific
     arguments for security reasons.
     """
     opts = pycompat.byteskwargs(opts)
 
     if not opts[b'sshstdio']:
         raise error.Abort(_(b'only --sshstdio is currently supported'))
 
     logfh = None
 
     if opts[b'logiofd'] and opts[b'logiofile']:
         raise error.Abort(_(b'cannot use both --logiofd and --logiofile'))
 
     if opts[b'logiofd']:
         # Ideally we would be line buffered. But line buffering in binary
         # mode isn't supported and emits a warning in Python 3.8+. Disabling
         # buffering could have performance impacts. But since this isn't
         # performance critical code, it should be fine.
         try:
             logfh = os.fdopen(int(opts[b'logiofd']), 'ab', 0)
         except OSError as e:
             if e.errno != errno.ESPIPE:
                 raise
             # can't seek a pipe, so `ab` mode fails on py3
             logfh = os.fdopen(int(opts[b'logiofd']), 'wb', 0)
     elif opts[b'logiofile']:
         logfh = open(opts[b'logiofile'], b'ab', 0)
 
     s = wireprotoserver.sshserver(ui, repo, logfh=logfh)
     s.serve_forever()
 
 
 @command(b'debugsetparents', [], _(b'REV1 [REV2]'))
 def debugsetparents(ui, repo, rev1, rev2=None):
     """manually set the parents of the current working directory
 
     This is useful for writing repository conversion tools, but should
     be used with care. For example, neither the working directory nor the
     dirstate is updated, so file status may be incorrect after running this
     command.
 
     Returns 0 on success.
     """
 
     node1 = scmutil.revsingle(repo, rev1).node()
     node2 = scmutil.revsingle(repo, rev2, b'null').node()
 
     with repo.wlock():
         repo.setparents(node1, node2)
 
 
 @command(b'debugsidedata', cmdutil.debugrevlogopts, _(b'-c|-m|FILE REV'))
 def debugsidedata(ui, repo, file_, rev=None, **opts):
     """dump the side data for a cl/manifest/file revision
 
     Use --verbose to dump the sidedata content."""
     opts = pycompat.byteskwargs(opts)
     if opts.get(b'changelog') or opts.get(b'manifest') or opts.get(b'dir'):
         if rev is not None:
             raise error.CommandError(b'debugdata', _(b'invalid arguments'))
         file_, rev = None, file_
     elif rev is None:
         raise error.CommandError(b'debugdata', _(b'invalid arguments'))
     r = cmdutil.openstorage(repo, b'debugdata', file_, opts)
     r = getattr(r, '_revlog', r)
     try:
         sidedata = r.sidedata(r.lookup(rev))
     except KeyError:
         raise error.Abort(_(b'invalid revision identifier %s') % rev)
     if sidedata:
         sidedata = list(sidedata.items())
         sidedata.sort()
         ui.writenoi18n(b'%d sidedata entries\n' % len(sidedata))
         for key, value in sidedata:
             ui.writenoi18n(b' entry-%04o size %d\n' % (key, len(value)))
             if ui.verbose:
                 ui.writenoi18n(b'  %s\n' % stringutil.pprint(value))
 
 
 @command(b'debugssl', [], b'[SOURCE]', optionalrepo=True)
 def debugssl(ui, repo, source=None, **opts):
     """test a secure connection to a server
 
     This builds the certificate chain for the server on Windows, installing the
     missing intermediates and trusted root via Windows Update if necessary.  It
     does nothing on other platforms.
 
     If SOURCE is omitted, the 'default' path will be used.  If a URL is given,
     that server is used. See :hg:`help urls` for more information.
 
     If the update succeeds, retry the original operation.  Otherwise, the cause
     of the SSL error is likely another issue.
     """
     if not pycompat.iswindows:
         raise error.Abort(
             _(b'certificate chain building is only possible on Windows')
         )
 
     if not source:
         if not repo:
             raise error.Abort(
                 _(
                     b"there is no Mercurial repository here, and no "
                     b"server specified"
                 )
             )
         source = b"default"
 
     source, branches = hg.parseurl(ui.expandpath(source))
     url = util.url(source)
 
     defaultport = {b'https': 443, b'ssh': 22}
     if url.scheme in defaultport:
         try:
             addr = (url.host, int(url.port or defaultport[url.scheme]))
         except ValueError:
             raise error.Abort(_(b"malformed port number in URL"))
     else:
         raise error.Abort(_(b"only https and ssh connections are supported"))
 
     from . import win32
 
     s = ssl.wrap_socket(
         socket.socket(),
         ssl_version=ssl.PROTOCOL_TLS,
         cert_reqs=ssl.CERT_NONE,
         ca_certs=None,
     )
 
     try:
         s.connect(addr)
         cert = s.getpeercert(True)
 
         ui.status(_(b'checking the certificate chain for %s\n') % url.host)
 
         complete = win32.checkcertificatechain(cert, build=False)
 
         if not complete:
             ui.status(_(b'certificate chain is incomplete, updating... '))
 
             if not win32.checkcertificatechain(cert):
                 ui.status(_(b'failed.\n'))
             else:
                 ui.status(_(b'done.\n'))
         else:
             ui.status(_(b'full certificate chain is available\n'))
     finally:
         s.close()
 
 
 @command(
     b"debugbackupbundle",
     [
         (
             b"",
             b"recover",
             b"",
             b"brings the specified changeset back into the repository",
         )
     ]
     + cmdutil.logopts,
     _(b"hg debugbackupbundle [--recover HASH]"),
 )
 def debugbackupbundle(ui, repo, *pats, **opts):
     """lists the changesets available in backup bundles
 
     Without any arguments, this command prints a list of the changesets in each
     backup bundle.
 
     --recover takes a changeset hash and unbundles the first bundle that
     contains that hash, which puts that changeset back in your repository.
 
     --verbose will print the entire commit message and the bundle path for that
     backup.
     """
     backups = list(
         filter(
             os.path.isfile, glob.glob(repo.vfs.join(b"strip-backup") + b"/*.hg")
         )
     )
     backups.sort(key=lambda x: os.path.getmtime(x), reverse=True)
 
     opts = pycompat.byteskwargs(opts)
     opts[b"bundle"] = b""
     opts[b"force"] = None
     limit = logcmdutil.getlimit(opts)
 
     def display(other, chlist, displayer):
         if opts.get(b"newest_first"):
             chlist.reverse()
         count = 0
         for n in chlist:
             if limit is not None and count >= limit:
                 break
             parents = [True for p in other.changelog.parents(n) if p != nullid]
             if opts.get(b"no_merges") and len(parents) == 2:
                 continue
             count += 1
             displayer.show(other[n])
 
     recovernode = opts.get(b"recover")
     if recovernode:
         if scmutil.isrevsymbol(repo, recovernode):
             ui.warn(_(b"%s already exists in the repo\n") % recovernode)
             return
     elif backups:
         msg = _(
             b"Recover changesets using: hg debugbackupbundle --recover "
             b"<changeset hash>\n\nAvailable backup changesets:"
         )
         ui.status(msg, label=b"status.removed")
     else:
         ui.status(_(b"no backup changesets found\n"))
         return
 
     for backup in backups:
         # Much of this is copied from the hg incoming logic
         source = ui.expandpath(os.path.relpath(backup, encoding.getcwd()))
         source, branches = hg.parseurl(source, opts.get(b"branch"))
         try:
             other = hg.peer(repo, opts, source)
         except error.LookupError as ex:
             msg = _(b"\nwarning: unable to open bundle %s") % source
             hint = _(b"\n(missing parent rev %s)\n") % short(ex.name)
             ui.warn(msg, hint=hint)
             continue
         revs, checkout = hg.addbranchrevs(
             repo, other, branches, opts.get(b"rev")
         )
 
         if revs:
             revs = [other.lookup(rev) for rev in revs]
 
         quiet = ui.quiet
         try:
             ui.quiet = True
             other, chlist, cleanupfn = bundlerepo.getremotechanges(
                 ui, repo, other, revs, opts[b"bundle"], opts[b"force"]
             )
         except error.LookupError:
             continue
         finally:
             ui.quiet = quiet
 
         try:
             if not chlist:
                 continue
             if recovernode:
                 with repo.lock(), repo.transaction(b"unbundle") as tr:
                     if scmutil.isrevsymbol(other, recovernode):
                         ui.status(_(b"Unbundling %s\n") % (recovernode))
                         f = hg.openpath(ui, source)
                         gen = exchange.readbundle(ui, f, source)
                         if isinstance(gen, bundle2.unbundle20):
                             bundle2.applybundle(
                                 repo,
                                 gen,
                                 tr,
                                 source=b"unbundle",
                                 url=b"bundle:" + source,
                             )
                         else:
                             gen.apply(repo, b"unbundle", b"bundle:" + source)
                         break
             else:
                 backupdate = encoding.strtolocal(
                     time.strftime(
                         "%a %H:%M, %Y-%m-%d",
                         time.localtime(os.path.getmtime(source)),
                     )
                 )
                 ui.status(b"\n%s\n" % (backupdate.ljust(50)))
                 if ui.verbose:
                     ui.status(b"%s%s\n" % (b"bundle:".ljust(13), source))
                 else:
                     opts[
                         b"template"
                     ] = b"{label('status.modified', node|short)} {desc|firstline}\n"
                 displayer = logcmdutil.changesetdisplayer(
                     ui, other, opts, False
                 )
                 display(other, chlist, displayer)
                 displayer.close()
         finally:
             cleanupfn()
 
 
 @command(
     b'debugsub',
     [(b'r', b'rev', b'', _(b'revision to check'), _(b'REV'))],
     _(b'[-r REV] [REV]'),
 )
 def debugsub(ui, repo, rev=None):
     ctx = scmutil.revsingle(repo, rev, None)
     for k, v in sorted(ctx.substate.items()):
         ui.writenoi18n(b'path %s\n' % k)
         ui.writenoi18n(b' source   %s\n' % v[0])
         ui.writenoi18n(b' revision %s\n' % v[1])
 
 
 @command(
     b'debugsuccessorssets',
     [(b'', b'closest', False, _(b'return closest successors sets only'))],
     _(b'[REV]'),
 )
 def debugsuccessorssets(ui, repo, *revs, **opts):
     """show set of successors for revision
 
     A successors set of changeset A is a consistent group of revisions that
     succeed A. It contains non-obsolete changesets only unless closests
     successors set is set.
 
     In most cases a changeset A has a single successors set containing a single
     successor (changeset A replaced by A').
 
     A changeset that is made obsolete with no successors are called "pruned".
     Such changesets have no successors sets at all.
 
     A changeset that has been "split" will have a successors set containing
     more than one successor.
 
     A changeset that has been rewritten in multiple different ways is called
     "divergent". Such changesets have multiple successor sets (each of which
     may also be split, i.e. have multiple successors).
 
     Results are displayed as follows::
 
         <rev1>
             <successors-1A>
         <rev2>
             <successors-2A>
             <successors-2B1> <successors-2B2> <successors-2B3>
 
     Here rev2 has two possible (i.e. divergent) successors sets. The first
     holds one element, whereas the second holds three (i.e. the changeset has
     been split).
     """
     # passed to successorssets caching computation from one call to another
     cache = {}
     ctx2str = bytes
     node2str = short
     for rev in scmutil.revrange(repo, revs):
         ctx = repo[rev]
         ui.write(b'%s\n' % ctx2str(ctx))
         for succsset in obsutil.successorssets(
             repo, ctx.node(), closest=opts['closest'], cache=cache
         ):
             if succsset:
                 ui.write(b'    ')
                 ui.write(node2str(succsset[0]))
                 for node in succsset[1:]:
                     ui.write(b' ')
                     ui.write(node2str(node))
             ui.write(b'\n')
 
 
 @command(b'debugtagscache', [])
 def debugtagscache(ui, repo):
     """display the contents of .hg/cache/hgtagsfnodes1"""
     cache = tagsmod.hgtagsfnodescache(repo.unfiltered())
     for r in repo:
         node = repo[r].node()
         tagsnode = cache.getfnode(node, computemissing=False)
         tagsnodedisplay = hex(tagsnode) if tagsnode else b'missing/invalid'
         ui.write(b'%d %s %s\n' % (r, hex(node), tagsnodedisplay))
 
 
 @command(
     b'debugtemplate',
     [
         (b'r', b'rev', [], _(b'apply template on changesets'), _(b'REV')),
         (b'D', b'define', [], _(b'define template keyword'), _(b'KEY=VALUE')),
     ],
     _(b'[-r REV]... [-D KEY=VALUE]... TEMPLATE'),
     optionalrepo=True,
 )
 def debugtemplate(ui, repo, tmpl, **opts):
     """parse and apply a template
 
     If -r/--rev is given, the template is processed as a log template and
     applied to the given changesets. Otherwise, it is processed as a generic
     template.
 
     Use --verbose to print the parsed tree.
     """
     revs = None
     if opts['rev']:
         if repo is None:
             raise error.RepoError(
                 _(b'there is no Mercurial repository here (.hg not found)')
             )
         revs = scmutil.revrange(repo, opts['rev'])
 
     props = {}
     for d in opts['define']:
         try:
             k, v = (e.strip() for e in d.split(b'=', 1))
             if not k or k == b'ui':
                 raise ValueError
             props[k] = v
         except ValueError:
             raise error.Abort(_(b'malformed keyword definition: %s') % d)
 
     if ui.verbose:
         aliases = ui.configitems(b'templatealias')
         tree = templater.parse(tmpl)
         ui.note(templater.prettyformat(tree), b'\n')
         newtree = templater.expandaliases(tree, aliases)
         if newtree != tree:
             ui.notenoi18n(
                 b"* expanded:\n", templater.prettyformat(newtree), b'\n'
             )
 
     if revs is None:
         tres = formatter.templateresources(ui, repo)
         t = formatter.maketemplater(ui, tmpl, resources=tres)
         if ui.verbose:
             kwds, funcs = t.symbolsuseddefault()
             ui.writenoi18n(b"* keywords: %s\n" % b', '.join(sorted(kwds)))
             ui.writenoi18n(b"* functions: %s\n" % b', '.join(sorted(funcs)))
         ui.write(t.renderdefault(props))
     else:
         displayer = logcmdutil.maketemplater(ui, repo, tmpl)
         if ui.verbose:
             kwds, funcs = displayer.t.symbolsuseddefault()
             ui.writenoi18n(b"* keywords: %s\n" % b', '.join(sorted(kwds)))
             ui.writenoi18n(b"* functions: %s\n" % b', '.join(sorted(funcs)))
         for r in revs:
             displayer.show(repo[r], **pycompat.strkwargs(props))
         displayer.close()
 
 
 @command(
     b'debuguigetpass',
     [
         (b'p', b'prompt', b'', _(b'prompt text'), _(b'TEXT')),
     ],
     _(b'[-p TEXT]'),
     norepo=True,
 )
 def debuguigetpass(ui, prompt=b''):
     """show prompt to type password"""
     r = ui.getpass(prompt)
     if r is not None:
         r = encoding.strtolocal(r)
     else:
         r = b"<default response>"
     ui.writenoi18n(b'response: %s\n' % r)
 
 
 @command(
     b'debuguiprompt',
     [
         (b'p', b'prompt', b'', _(b'prompt text'), _(b'TEXT')),
     ],
     _(b'[-p TEXT]'),
     norepo=True,
 )
 def debuguiprompt(ui, prompt=b''):
     """show plain prompt"""
     r = ui.prompt(prompt)
     ui.writenoi18n(b'response: %s\n' % r)
 
 
 @command(b'debugupdatecaches', [])
 def debugupdatecaches(ui, repo, *pats, **opts):
     """warm all known caches in the repository"""
     with repo.wlock(), repo.lock():
         repo.updatecaches(full=True)
 
 
 @command(
     b'debugupgraderepo',
     [
         (
             b'o',
             b'optimize',
             [],
             _(b'extra optimization to perform'),
             _(b'NAME'),
         ),
         (b'', b'run', False, _(b'performs an upgrade')),
         (b'', b'backup', True, _(b'keep the old repository content around')),
         (b'', b'changelog', None, _(b'select the changelog for upgrade')),
         (b'', b'manifest', None, _(b'select the manifest for upgrade')),
         (b'', b'filelogs', None, _(b'select all filelogs for upgrade')),
     ],
 )
 def debugupgraderepo(ui, repo, run=False, optimize=None, backup=True, **opts):
     """upgrade a repository to use different features
 
     If no arguments are specified, the repository is evaluated for upgrade
     and a list of problems and potential optimizations is printed.
 
     With ``--run``, a repository upgrade is performed. Behavior of the upgrade
     can be influenced via additional arguments. More details will be provided
     by the command output when run without ``--run``.
 
     During the upgrade, the repository will be locked and no writes will be
     allowed.
 
     At the end of the upgrade, the repository may not be readable while new
     repository data is swapped in. This window will be as long as it takes to
     rename some directories inside the ``.hg`` directory. On most machines, this
     should complete almost instantaneously and the chances of a consumer being
     unable to access the repository should be low.
 
     By default, all revlog will be upgraded. You can restrict this using flag
     such as `--manifest`:
 
       * `--manifest`: only optimize the manifest
       * `--no-manifest`: optimize all revlog but the manifest
       * `--changelog`: optimize the changelog only
       * `--no-changelog --no-manifest`: optimize filelogs only
       * `--filelogs`: optimize the filelogs only
       * `--no-changelog --no-manifest --no-filelogs`: skip all filelog optimisation
     """
     return upgrade.upgraderepo(
         ui, repo, run=run, optimize=optimize, backup=backup, **opts
     )
 
 
 @command(
     b'debugwalk', cmdutil.walkopts, _(b'[OPTION]... [FILE]...'), inferrepo=True
 )
 def debugwalk(ui, repo, *pats, **opts):
     """show how files match on given patterns"""
     opts = pycompat.byteskwargs(opts)
     m = scmutil.match(repo[None], pats, opts)
     if ui.verbose:
         ui.writenoi18n(b'* matcher:\n', stringutil.prettyrepr(m), b'\n')
     items = list(repo[None].walk(m))
     if not items:
         return
     f = lambda fn: fn
     if ui.configbool(b'ui', b'slash') and pycompat.ossep != b'/':
         f = lambda fn: util.normpath(fn)
     fmt = b'f  %%-%ds  %%-%ds  %%s' % (
         max([len(abs) for abs in items]),
         max([len(repo.pathto(abs)) for abs in items]),
     )
     for abs in items:
         line = fmt % (
             abs,
             f(repo.pathto(abs)),
             m.exact(abs) and b'exact' or b'',
         )
         ui.write(b"%s\n" % line.rstrip())
 
 
 @command(b'debugwhyunstable', [], _(b'REV'))
 def debugwhyunstable(ui, repo, rev):
     """explain instabilities of a changeset"""
     for entry in obsutil.whyunstable(repo, scmutil.revsingle(repo, rev)):
         dnodes = b''
         if entry.get(b'divergentnodes'):
             dnodes = (
                 b' '.join(
                     b'%s (%s)' % (ctx.hex(), ctx.phasestr())
                     for ctx in entry[b'divergentnodes']
                 )
                 + b' '
             )
         ui.write(
             b'%s: %s%s %s\n'
             % (entry[b'instability'], dnodes, entry[b'reason'], entry[b'node'])
         )
 
 
 @command(
     b'debugwireargs',
     [
         (b'', b'three', b'', b'three'),
         (b'', b'four', b'', b'four'),
         (b'', b'five', b'', b'five'),
     ]
     + cmdutil.remoteopts,
     _(b'REPO [OPTIONS]... [ONE [TWO]]'),
     norepo=True,
 )
 def debugwireargs(ui, repopath, *vals, **opts):
     opts = pycompat.byteskwargs(opts)
     repo = hg.peer(ui, opts, repopath)
     for opt in cmdutil.remoteopts:
         del opts[opt[1]]
     args = {}
     for k, v in pycompat.iteritems(opts):
         if v:
             args[k] = v
     args = pycompat.strkwargs(args)
     # run twice to check that we don't mess up the stream for the next command
     res1 = repo.debugwireargs(*vals, **args)
     res2 = repo.debugwireargs(*vals, **args)
     ui.write(b"%s\n" % res1)
     if res1 != res2:
         ui.warn(b"%s\n" % res2)
 
 
 def _parsewirelangblocks(fh):
     activeaction = None
     blocklines = []
     lastindent = 0
 
     for line in fh:
         line = line.rstrip()
         if not line:
             continue
 
         if line.startswith(b'#'):
             continue
 
         if not line.startswith(b' '):
             # New block. Flush previous one.
             if activeaction:
                 yield activeaction, blocklines
 
             activeaction = line
             blocklines = []
             lastindent = 0
             continue
 
         # Else we start with an indent.
 
         if not activeaction:
             raise error.Abort(_(b'indented line outside of block'))
 
         indent = len(line) - len(line.lstrip())
 
         # If this line is indented more than the last line, concatenate it.
         if indent > lastindent and blocklines:
             blocklines[-1] += line.lstrip()
         else:
             blocklines.append(line)
             lastindent = indent
 
     # Flush last block.
     if activeaction:
         yield activeaction, blocklines
 
 
 @command(
     b'debugwireproto',
     [
         (b'', b'localssh', False, _(b'start an SSH server for this repo')),
         (b'', b'peer', b'', _(b'construct a specific version of the peer')),
         (
             b'',
             b'noreadstderr',
             False,
             _(b'do not read from stderr of the remote'),
         ),
         (
             b'',
             b'nologhandshake',
             False,
             _(b'do not log I/O related to the peer handshake'),
         ),
     ]
     + cmdutil.remoteopts,
     _(b'[PATH]'),
     optionalrepo=True,
 )
 def debugwireproto(ui, repo, path=None, **opts):
     """send wire protocol commands to a server
 
     This command can be used to issue wire protocol commands to remote
     peers and to debug the raw data being exchanged.
 
     ``--localssh`` will start an SSH server against the current repository
     and connect to that. By default, the connection will perform a handshake
     and establish an appropriate peer instance.
 
     ``--peer`` can be used to bypass the handshake protocol and construct a
     peer instance using the specified class type. Valid values are ``raw``,
     ``http2``, ``ssh1``, and ``ssh2``. ``raw`` instances only allow sending
     raw data payloads and don't support higher-level command actions.
 
     ``--noreadstderr`` can be used to disable automatic reading from stderr
     of the peer (for SSH connections only). Disabling automatic reading of
     stderr is useful for making output more deterministic.
 
     Commands are issued via a mini language which is specified via stdin.
     The language consists of individual actions to perform. An action is
     defined by a block. A block is defined as a line with no leading
     space followed by 0 or more lines with leading space. Blocks are
     effectively a high-level command with additional metadata.
 
     Lines beginning with ``#`` are ignored.
 
     The following sections denote available actions.
 
     raw
     ---
 
     Send raw data to the server.
 
     The block payload contains the raw data to send as one atomic send
     operation. The data may not actually be delivered in a single system
     call: it depends on the abilities of the transport being used.
 
     Each line in the block is de-indented and concatenated. Then, that
     value is evaluated as a Python b'' literal. This allows the use of
     backslash escaping, etc.
 
     raw+
     ----
 
     Behaves like ``raw`` except flushes output afterwards.
 
     command <X>
     -----------
 
     Send a request to run a named command, whose name follows the ``command``
     string.
 
     Arguments to the command are defined as lines in this block. The format of
     each line is ``<key> <value>``. e.g.::
 
        command listkeys
            namespace bookmarks
 
     If the value begins with ``eval:``, it will be interpreted as a Python
     literal expression. Otherwise values are interpreted as Python b'' literals.
     This allows sending complex types and encoding special byte sequences via
     backslash escaping.
 
     The following arguments have special meaning:
 
     ``PUSHFILE``
         When defined, the *push* mechanism of the peer will be used instead
         of the static request-response mechanism and the content of the
         file specified in the value of this argument will be sent as the
         command payload.
 
         This can be used to submit a local bundle file to the remote.
 
     batchbegin
     ----------
 
     Instruct the peer to begin a batched send.
 
     All ``command`` blocks are queued for execution until the next
     ``batchsubmit`` block.
 
     batchsubmit
     -----------
 
     Submit previously queued ``command`` blocks as a batch request.
 
     This action MUST be paired with a ``batchbegin`` action.
 
     httprequest <method> <path>
     ---------------------------
 
     (HTTP peer only)
 
     Send an HTTP request to the peer.
 
     The HTTP request line follows the ``httprequest`` action. e.g. ``GET /foo``.
 
     Arguments of the form ``<key>: <value>`` are interpreted as HTTP request
     headers to add to the request. e.g. ``Accept: foo``.
 
     The following arguments are special:
 
     ``BODYFILE``
         The content of the file defined as the value to this argument will be
         transferred verbatim as the HTTP request body.
 
     ``frame <type> <flags> <payload>``
         Send a unified protocol frame as part of the request body.
 
         All frames will be collected and sent as the body to the HTTP
         request.
 
     close
     -----
 
     Close the connection to the server.
 
     flush
     -----
 
     Flush data written to the server.
 
     readavailable
     -------------
 
     Close the write end of the connection and read all available data from
     the server.
 
     If the connection to the server encompasses multiple pipes, we poll both
     pipes and read available data.
 
     readline
     --------
 
     Read a line of output from the server. If there are multiple output
     pipes, reads only the main pipe.
 
     ereadline
     ---------
 
     Like ``readline``, but read from the stderr pipe, if available.
 
     read <X>
     --------
 
     ``read()`` N bytes from the server's main output pipe.
 
     eread <X>
     ---------
 
     ``read()`` N bytes from the server's stderr pipe, if available.
 
     Specifying Unified Frame-Based Protocol Frames
     ----------------------------------------------
 
     It is possible to emit a *Unified Frame-Based Protocol* by using special
     syntax.
 
     A frame is composed as a type, flags, and payload. These can be parsed
     from a string of the form:
 
        <request-id> <stream-id> <stream-flags> <type> <flags> <payload>
 
     ``request-id`` and ``stream-id`` are integers defining the request and
     stream identifiers.
 
     ``type`` can be an integer value for the frame type or the string name
     of the type. The strings are defined in ``wireprotoframing.py``. e.g.
     ``command-name``.
 
     ``stream-flags`` and ``flags`` are a ``|`` delimited list of flag
     components. Each component (and there can be just one) can be an integer
     or a flag name for stream flags or frame flags, respectively. Values are
     resolved to integers and then bitwise OR'd together.
 
     ``payload`` represents the raw frame payload. If it begins with
     ``cbor:``, the following string is evaluated as Python code and the
     resulting object is fed into a CBOR encoder. Otherwise it is interpreted
     as a Python byte string literal.
     """
     opts = pycompat.byteskwargs(opts)
 
     if opts[b'localssh'] and not repo:
         raise error.Abort(_(b'--localssh requires a repository'))
 
     if opts[b'peer'] and opts[b'peer'] not in (
         b'raw',
         b'http2',
         b'ssh1',
         b'ssh2',
     ):
         raise error.Abort(
             _(b'invalid value for --peer'),
             hint=_(b'valid values are "raw", "ssh1", and "ssh2"'),
         )
 
     if path and opts[b'localssh']:
         raise error.Abort(_(b'cannot specify --localssh with an explicit path'))
 
     if ui.interactive():
         ui.write(_(b'(waiting for commands on stdin)\n'))
 
     blocks = list(_parsewirelangblocks(ui.fin))
 
     proc = None
     stdin = None
     stdout = None
     stderr = None
     opener = None
 
     if opts[b'localssh']:
         # We start the SSH server in its own process so there is process
         # separation. This prevents a whole class of potential bugs around
         # shared state from interfering with server operation.
         args = procutil.hgcmd() + [
             b'-R',
             repo.root,
             b'debugserve',
             b'--sshstdio',
         ]
         proc = subprocess.Popen(
             pycompat.rapply(procutil.tonativestr, args),
             stdin=subprocess.PIPE,
             stdout=subprocess.PIPE,
             stderr=subprocess.PIPE,
             bufsize=0,
         )
 
         stdin = proc.stdin
         stdout = proc.stdout
         stderr = proc.stderr
 
         # We turn the pipes into observers so we can log I/O.
         if ui.verbose or opts[b'peer'] == b'raw':
             stdin = util.makeloggingfileobject(
                 ui, proc.stdin, b'i', logdata=True
             )
             stdout = util.makeloggingfileobject(
                 ui, proc.stdout, b'o', logdata=True
             )
             stderr = util.makeloggingfileobject(
                 ui, proc.stderr, b'e', logdata=True
             )
 
         # --localssh also implies the peer connection settings.
 
         url = b'ssh://localserver'
         autoreadstderr = not opts[b'noreadstderr']
 
         if opts[b'peer'] == b'ssh1':
             ui.write(_(b'creating ssh peer for wire protocol version 1\n'))
             peer = sshpeer.sshv1peer(
                 ui,
                 url,
                 proc,
                 stdin,
                 stdout,
                 stderr,
                 None,
                 autoreadstderr=autoreadstderr,
             )
         elif opts[b'peer'] == b'ssh2':
             ui.write(_(b'creating ssh peer for wire protocol version 2\n'))
             peer = sshpeer.sshv2peer(
                 ui,
                 url,
                 proc,
                 stdin,
                 stdout,
                 stderr,
                 None,
                 autoreadstderr=autoreadstderr,
             )
         elif opts[b'peer'] == b'raw':
             ui.write(_(b'using raw connection to peer\n'))
             peer = None
         else:
             ui.write(_(b'creating ssh peer from handshake results\n'))
             peer = sshpeer.makepeer(
                 ui,
                 url,
                 proc,
                 stdin,
                 stdout,
                 stderr,
                 autoreadstderr=autoreadstderr,
             )
 
     elif path:
         # We bypass hg.peer() so we can proxy the sockets.
         # TODO consider not doing this because we skip
         # ``hg.wirepeersetupfuncs`` and potentially other useful functionality.
         u = util.url(path)
         if u.scheme != b'http':
             raise error.Abort(_(b'only http:// paths are currently supported'))
 
         url, authinfo = u.authinfo()
         openerargs = {
             'useragent': b'Mercurial debugwireproto',
         }
 
         # Turn pipes/sockets into observers so we can log I/O.
         if ui.verbose:
             openerargs.update(
                 {
                     'loggingfh': ui,
                     'loggingname': b's',
                     'loggingopts': {
                         'logdata': True,
                         'logdataapis': False,
                     },
                 }
             )
 
         if ui.debugflag:
             openerargs['loggingopts']['logdataapis'] = True
 
         # Don't send default headers when in raw mode. This allows us to
         # bypass most of the behavior of our URL handling code so we can
         # have near complete control over what's sent on the wire.
         if opts[b'peer'] == b'raw':
             openerargs['sendaccept'] = False
 
         opener = urlmod.opener(ui, authinfo, **openerargs)
 
         if opts[b'peer'] == b'http2':
             ui.write(_(b'creating http peer for wire protocol version 2\n'))
             # We go through makepeer() because we need an API descriptor for
             # the peer instance to be useful.
             with ui.configoverride(
                 {(b'experimental', b'httppeer.advertise-v2'): True}
             ):
                 if opts[b'nologhandshake']:
                     ui.pushbuffer()
 
                 peer = httppeer.makepeer(ui, path, opener=opener)
 
                 if opts[b'nologhandshake']:
                     ui.popbuffer()
 
             if not isinstance(peer, httppeer.httpv2peer):
                 raise error.Abort(
                     _(
                         b'could not instantiate HTTP peer for '
                         b'wire protocol version 2'
                     ),
                     hint=_(
                         b'the server may not have the feature '
                         b'enabled or is not allowing this '
                         b'client version'
                     ),
                 )
 
         elif opts[b'peer'] == b'raw':
             ui.write(_(b'using raw connection to peer\n'))
             peer = None
         elif opts[b'peer']:
             raise error.Abort(
                 _(b'--peer %s not supported with HTTP peers') % opts[b'peer']
             )
         else:
             peer = httppeer.makepeer(ui, path, opener=opener)
 
         # We /could/ populate stdin/stdout with sock.makefile()...
     else:
         raise error.Abort(_(b'unsupported connection configuration'))
 
     batchedcommands = None
 
     # Now perform actions based on the parsed wire language instructions.
     for action, lines in blocks:
         if action in (b'raw', b'raw+'):
             if not stdin:
                 raise error.Abort(_(b'cannot call raw/raw+ on this peer'))
 
             # Concatenate the data together.
             data = b''.join(l.lstrip() for l in lines)
             data = stringutil.unescapestr(data)
             stdin.write(data)
 
             if action == b'raw+':
                 stdin.flush()
         elif action == b'flush':
             if not stdin:
                 raise error.Abort(_(b'cannot call flush on this peer'))
             stdin.flush()
         elif action.startswith(b'command'):
             if not peer:
                 raise error.Abort(
                     _(
                         b'cannot send commands unless peer instance '
                         b'is available'
                     )
                 )
 
             command = action.split(b' ', 1)[1]
 
             args = {}
             for line in lines:
                 # We need to allow empty values.
                 fields = line.lstrip().split(b' ', 1)
                 if len(fields) == 1:
                     key = fields[0]
                     value = b''
                 else:
                     key, value = fields
 
                 if value.startswith(b'eval:'):
                     value = stringutil.evalpythonliteral(value[5:])
                 else:
                     value = stringutil.unescapestr(value)
 
                 args[key] = value
 
             if batchedcommands is not None:
                 batchedcommands.append((command, args))
                 continue
 
             ui.status(_(b'sending %s command\n') % command)
 
             if b'PUSHFILE' in args:
                 with open(args[b'PUSHFILE'], 'rb') as fh:
                     del args[b'PUSHFILE']
                     res, output = peer._callpush(
                         command, fh, **pycompat.strkwargs(args)
                     )
                     ui.status(_(b'result: %s\n') % stringutil.escapestr(res))
                     ui.status(
                         _(b'remote output: %s\n') % stringutil.escapestr(output)
                     )
             else:
                 with peer.commandexecutor() as e:
                     res = e.callcommand(command, args).result()
 
                 if isinstance(res, wireprotov2peer.commandresponse):
                     val = res.objects()
                     ui.status(
                         _(b'response: %s\n')
                         % stringutil.pprint(val, bprefix=True, indent=2)
                     )
                 else:
                     ui.status(
                         _(b'response: %s\n')
                         % stringutil.pprint(res, bprefix=True, indent=2)
                     )
 
         elif action == b'batchbegin':
             if batchedcommands is not None:
                 raise error.Abort(_(b'nested batchbegin not allowed'))
 
             batchedcommands = []
         elif action == b'batchsubmit':
             # There is a batching API we could go through. But it would be
             # difficult to normalize requests into function calls. It is easier
             # to bypass this layer and normalize to commands + args.
             ui.status(
                 _(b'sending batch with %d sub-commands\n')
                 % len(batchedcommands)
             )
             assert peer is not None
             for i, chunk in enumerate(peer._submitbatch(batchedcommands)):
                 ui.status(
                     _(b'response #%d: %s\n') % (i, stringutil.escapestr(chunk))
                 )
 
             batchedcommands = None
 
         elif action.startswith(b'httprequest '):
             if not opener:
                 raise error.Abort(
                     _(b'cannot use httprequest without an HTTP peer')
                 )
 
             request = action.split(b' ', 2)
             if len(request) != 3:
                 raise error.Abort(
                     _(
                         b'invalid httprequest: expected format is '
                         b'"httprequest <method> <path>'
                     )
                 )
 
             method, httppath = request[1:]
             headers = {}
             body = None
             frames = []
             for line in lines:
                 line = line.lstrip()
                 m = re.match(b'^([a-zA-Z0-9_-]+): (.*)$', line)
                 if m:
                     # Headers need to use native strings.
                     key = pycompat.strurl(m.group(1))
                     value = pycompat.strurl(m.group(2))
                     headers[key] = value
                     continue
 
                 if line.startswith(b'BODYFILE '):
                     with open(line.split(b' ', 1), b'rb') as fh:
                         body = fh.read()
                 elif line.startswith(b'frame '):
                     frame = wireprotoframing.makeframefromhumanstring(
                         line[len(b'frame ') :]
                     )
 
                     frames.append(frame)
                 else:
                     raise error.Abort(
                         _(b'unknown argument to httprequest: %s') % line
                     )
 
             url = path + httppath
 
             if frames:
                 body = b''.join(bytes(f) for f in frames)
 
             req = urlmod.urlreq.request(pycompat.strurl(url), body, headers)
 
             # urllib.Request insists on using has_data() as a proxy for
             # determining the request method. Override that to use our
             # explicitly requested method.
             req.get_method = lambda: pycompat.sysstr(method)
 
             try:
                 res = opener.open(req)
                 body = res.read()
             except util.urlerr.urlerror as e:
                 # read() method must be called, but only exists in Python 2
                 getattr(e, 'read', lambda: None)()
                 continue
 
             ct = res.headers.get('Content-Type')
             if ct == 'application/mercurial-cbor':
                 ui.write(
                     _(b'cbor> %s\n')
                     % stringutil.pprint(
                         cborutil.decodeall(body), bprefix=True, indent=2
                     )
                 )
 
         elif action == b'close':
             assert peer is not None
             peer.close()
         elif action == b'readavailable':
             if not stdout or not stderr:
                 raise error.Abort(
                     _(b'readavailable not available on this peer')
                 )
 
             stdin.close()
             stdout.read()
             stderr.read()
 
         elif action == b'readline':
             if not stdout:
                 raise error.Abort(_(b'readline not available on this peer'))
             stdout.readline()
         elif action == b'ereadline':
             if not stderr:
                 raise error.Abort(_(b'ereadline not available on this peer'))
             stderr.readline()
         elif action.startswith(b'read '):
             count = int(action.split(b' ', 1)[1])
             if not stdout:
                 raise error.Abort(_(b'read not available on this peer'))
             stdout.read(count)
         elif action.startswith(b'eread '):
             count = int(action.split(b' ', 1)[1])
             if not stderr:
                 raise error.Abort(_(b'eread not available on this peer'))
             stderr.read(count)
         else:
             raise error.Abort(_(b'unknown action: %s') % action)
 
     if batchedcommands is not None:
         raise error.Abort(_(b'unclosed "batchbegin" request'))
 
     if peer:
         peer.close()
 
     if proc:
         proc.kill()

tests/test-setdiscovery.t

@@ -1,1307 +1,1502
 
 Function to test discovery between two repos in both directions, using both the local shortcut
 (which is currently not activated by default) and the full remotable protocol:
 
   $ testdesc() { # revs_a, revs_b, dagdesc
   >     if [ -d foo ]; then rm -rf foo; fi
   >     hg init foo
   >     cd foo
   >     hg debugbuilddag "$3"
   >     hg clone . a $1 --quiet
   >     hg clone . b $2 --quiet
   >     echo
   >     echo "% -- a -> b tree"
   >     hg -R a debugdiscovery b --verbose --old
   >     echo
   >     echo "% -- a -> b set"
   >     hg -R a debugdiscovery b --verbose --debug --config progress.debug=true
   >     echo
   >     echo "% -- a -> b set (tip only)"
   >     hg -R a debugdiscovery b --verbose --debug --config progress.debug=true --rev tip
   >     echo
   >     echo "% -- b -> a tree"
   >     hg -R b debugdiscovery a --verbose --old
   >     echo
   >     echo "% -- b -> a set"
   >     hg -R b debugdiscovery a --verbose --debug --config progress.debug=true
   >     echo
   >     echo "% -- b -> a set (tip only)"
   >     hg -R b debugdiscovery a --verbose --debug --config progress.debug=true --rev tip
   >     cd ..
   > }
 
 
 Small superset:
 
   $ testdesc '-ra1 -ra2' '-rb1 -rb2 -rb3' '
   > +2:f +1:a1:b1
   > <f +4 :a2
   > +5 :b2
   > <f +3 :b3'
   
   % -- a -> b tree
   comparing with b
   searching for changes
   unpruned common: 01241442b3c2 66f7d451a68b b5714e113bc0
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          2
       also local heads:          2
       also remote heads:         1
       both:                      1
     local heads:                 2
       common:                    2
       missing:                   0
     remote heads:                3
       common:                    1
       unknown:                   2
   local changesets:              7
     common:                      7
       heads:                     2
       roots:                     1
     missing:                     0
       heads:                     0
       roots:                     0
+    first undecided set:         3
+      heads:                     1
+      roots:                     1
+      common:                    3
+      missing:                   0
   common heads: 01241442b3c2 b5714e113bc0
   
   % -- a -> b set
   comparing with b
   query 1; heads
   searching for changes
   all local changesets known remotely
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          2
       also local heads:          2
       also remote heads:         1
       both:                      1
     local heads:                 2
       common:                    2
       missing:                   0
     remote heads:                3
       common:                    1
       unknown:                   2
   local changesets:              7
     common:                      7
       heads:                     2
       roots:                     1
     missing:                     0
       heads:                     0
       roots:                     0
+    first undecided set:         3
+      heads:                     1
+      roots:                     1
+      common:                    3
+      missing:                   0
   common heads: 01241442b3c2 b5714e113bc0
   
   % -- a -> b set (tip only)
   comparing with b
   query 1; heads
   searching for changes
   all local changesets known remotely
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          1
       also remote heads:         0
       both:                      0
     local heads:                 2
       common:                    1
       missing:                   1
     remote heads:                3
       common:                    0
       unknown:                   3
   local changesets:              7
     common:                      6
       heads:                     1
       roots:                     1
     missing:                     1
       heads:                     1
       roots:                     1
+    first undecided set:         6
+      heads:                     2
+      roots:                     1
+      common:                    5
+      missing:                   1
   common heads: b5714e113bc0
   
   % -- b -> a tree
   comparing with a
   searching for changes
   unpruned common: 01241442b3c2 b5714e113bc0
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          2
       also local heads:          1
       also remote heads:         2
       both:                      1
     local heads:                 3
       common:                    1
       missing:                   2
     remote heads:                2
       common:                    2
       unknown:                   0
   local changesets:             15
     common:                      7
       heads:                     2
       roots:                     1
     missing:                     8
       heads:                     2
       roots:                     2
+    first undecided set:         8
+      heads:                     2
+      roots:                     2
+      common:                    0
+      missing:                   8
   common heads: 01241442b3c2 b5714e113bc0
   
   % -- b -> a set
   comparing with a
   query 1; heads
   searching for changes
   all remote heads known locally
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          2
       also local heads:          1
       also remote heads:         2
       both:                      1
     local heads:                 3
       common:                    1
       missing:                   2
     remote heads:                2
       common:                    2
       unknown:                   0
   local changesets:             15
     common:                      7
       heads:                     2
       roots:                     1
     missing:                     8
       heads:                     2
       roots:                     2
+    first undecided set:         8
+      heads:                     2
+      roots:                     2
+      common:                    0
+      missing:                   8
   common heads: 01241442b3c2 b5714e113bc0
   
   % -- b -> a set (tip only)
   comparing with a
   query 1; heads
   searching for changes
   all remote heads known locally
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          2
       also local heads:          1
       also remote heads:         2
       both:                      1
     local heads:                 3
       common:                    1
       missing:                   2
     remote heads:                2
       common:                    2
       unknown:                   0
   local changesets:             15
     common:                      7
       heads:                     2
       roots:                     1
     missing:                     8
       heads:                     2
       roots:                     2
+    first undecided set:         8
+      heads:                     2
+      roots:                     2
+      common:                    0
+      missing:                   8
   common heads: 01241442b3c2 b5714e113bc0
 
 
 Many new:
 
   $ testdesc '-ra1 -ra2' '-rb' '
   > +2:f +3:a1 +3:b
   > <f +30 :a2'
   
   % -- a -> b tree
   comparing with b
   searching for changes
   unpruned common: bebd167eb94d
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          1
       also remote heads:         0
       both:                      0
     local heads:                 2
       common:                    1
       missing:                   1
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:             35
     common:                      5
       heads:                     1
       roots:                     1
     missing:                    30
       heads:                     1
       roots:                     1
+    first undecided set:        34
+      heads:                     2
+      roots:                     1
+      common:                    4
+      missing:                  30
   common heads: bebd167eb94d
   
   % -- a -> b set
   comparing with b
   query 1; heads
   searching for changes
   taking initial sample
   searching: 2 queries
   query 2; still undecided: 29, sample size is: 29
   2 total queries in *.????s (glob)
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          1
       also remote heads:         0
       both:                      0
     local heads:                 2
       common:                    1
       missing:                   1
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:             35
     common:                      5
       heads:                     1
       roots:                     1
     missing:                    30
       heads:                     1
       roots:                     1
+    first undecided set:        34
+      heads:                     2
+      roots:                     1
+      common:                    4
+      missing:                  30
   common heads: bebd167eb94d
   
   % -- a -> b set (tip only)
   comparing with b
   query 1; heads
   searching for changes
   taking quick initial sample
   searching: 2 queries
   query 2; still undecided: 31, sample size is: 31
   2 total queries in *.????s (glob)
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         0
       both:                      0
     local heads:                 2
       common:                    0
       missing:                   2
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:             35
     common:                      2
       heads:                     1
       roots:                     1
     missing:                    33
       heads:                     2
       roots:                     2
+    first undecided set:        35
+      heads:                     2
+      roots:                     1
+      common:                    2
+      missing:                  33
   common heads: 66f7d451a68b
   
   % -- b -> a tree
   comparing with a
   searching for changes
   unpruned common: 66f7d451a68b bebd167eb94d
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         1
       both:                      0
     local heads:                 1
       common:                    0
       missing:                   1
     remote heads:                2
       common:                    1
       unknown:                   1
   local changesets:              8
     common:                      5
       heads:                     1
       roots:                     1
     missing:                     3
       heads:                     1
       roots:                     1
+    first undecided set:         3
+      heads:                     1
+      roots:                     1
+      common:                    0
+      missing:                   3
   common heads: bebd167eb94d
   
   % -- b -> a set
   comparing with a
   query 1; heads
   searching for changes
   taking initial sample
   searching: 2 queries
   query 2; still undecided: 2, sample size is: 2
   2 total queries in *.????s (glob)
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         1
       both:                      0
     local heads:                 1
       common:                    0
       missing:                   1
     remote heads:                2
       common:                    1
       unknown:                   1
   local changesets:              8
     common:                      5
       heads:                     1
       roots:                     1
     missing:                     3
       heads:                     1
       roots:                     1
+    first undecided set:         3
+      heads:                     1
+      roots:                     1
+      common:                    0
+      missing:                   3
   common heads: bebd167eb94d
   
   % -- b -> a set (tip only)
   comparing with a
   query 1; heads
   searching for changes
   taking initial sample
   searching: 2 queries
   query 2; still undecided: 2, sample size is: 2
   2 total queries in *.????s (glob)
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         1
       both:                      0
     local heads:                 1
       common:                    0
       missing:                   1
     remote heads:                2
       common:                    1
       unknown:                   1
   local changesets:              8
     common:                      5
       heads:                     1
       roots:                     1
     missing:                     3
       heads:                     1
       roots:                     1
+    first undecided set:         3
+      heads:                     1
+      roots:                     1
+      common:                    0
+      missing:                   3
   common heads: bebd167eb94d
 
 Both sides many new with stub:
 
   $ testdesc '-ra1 -ra2' '-rb' '
   > +2:f +2:a1 +30 :b
   > <f +30 :a2'
   
   % -- a -> b tree
   comparing with b
   searching for changes
   unpruned common: 2dc09a01254d
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          1
       also remote heads:         0
       both:                      0
     local heads:                 2
       common:                    1
       missing:                   1
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:             34
     common:                      4
       heads:                     1
       roots:                     1
     missing:                    30
       heads:                     1
       roots:                     1
+    first undecided set:        33
+      heads:                     2
+      roots:                     1
+      common:                    3
+      missing:                  30
   common heads: 2dc09a01254d
   
   % -- a -> b set
   comparing with b
   query 1; heads
   searching for changes
   taking initial sample
   searching: 2 queries
   query 2; still undecided: 29, sample size is: 29
   2 total queries in *.????s (glob)
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          1
       also remote heads:         0
       both:                      0
     local heads:                 2
       common:                    1
       missing:                   1
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:             34
     common:                      4
       heads:                     1
       roots:                     1
     missing:                    30
       heads:                     1
       roots:                     1
+    first undecided set:        33
+      heads:                     2
+      roots:                     1
+      common:                    3
+      missing:                  30
   common heads: 2dc09a01254d
   
   % -- a -> b set (tip only)
   comparing with b
   query 1; heads
   searching for changes
   taking quick initial sample
   searching: 2 queries
   query 2; still undecided: 31, sample size is: 31
   2 total queries in *.????s (glob)
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         0
       both:                      0
     local heads:                 2
       common:                    0
       missing:                   2
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:             34
     common:                      2
       heads:                     1
       roots:                     1
     missing:                    32
       heads:                     2
       roots:                     2
+    first undecided set:        34
+      heads:                     2
+      roots:                     1
+      common:                    2
+      missing:                  32
   common heads: 66f7d451a68b
   
   % -- b -> a tree
   comparing with a
   searching for changes
   unpruned common: 2dc09a01254d 66f7d451a68b
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         1
       both:                      0
     local heads:                 1
       common:                    0
       missing:                   1
     remote heads:                2
       common:                    1
       unknown:                   1
   local changesets:             34
     common:                      4
       heads:                     1
       roots:                     1
     missing:                    30
       heads:                     1
       roots:                     1
+    first undecided set:        30
+      heads:                     1
+      roots:                     1
+      common:                    0
+      missing:                  30
   common heads: 2dc09a01254d
   
   % -- b -> a set
   comparing with a
   query 1; heads
   searching for changes
   taking initial sample
   searching: 2 queries
   query 2; still undecided: 29, sample size is: 29
   2 total queries in *.????s (glob)
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         1
       both:                      0
     local heads:                 1
       common:                    0
       missing:                   1
     remote heads:                2
       common:                    1
       unknown:                   1
   local changesets:             34
     common:                      4
       heads:                     1
       roots:                     1
     missing:                    30
       heads:                     1
       roots:                     1
+    first undecided set:        30
+      heads:                     1
+      roots:                     1
+      common:                    0
+      missing:                  30
   common heads: 2dc09a01254d
   
   % -- b -> a set (tip only)
   comparing with a
   query 1; heads
   searching for changes
   taking initial sample
   searching: 2 queries
   query 2; still undecided: 29, sample size is: 29
   2 total queries in *.????s (glob)
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         1
       both:                      0
     local heads:                 1
       common:                    0
       missing:                   1
     remote heads:                2
       common:                    1
       unknown:                   1
   local changesets:             34
     common:                      4
       heads:                     1
       roots:                     1
     missing:                    30
       heads:                     1
       roots:                     1
+    first undecided set:        30
+      heads:                     1
+      roots:                     1
+      common:                    0
+      missing:                  30
   common heads: 2dc09a01254d
 
 
 Both many new:
 
   $ testdesc '-ra' '-rb' '
   > +2:f +30 :b
   > <f +30 :a'
   
   % -- a -> b tree
   comparing with b
   searching for changes
   unpruned common: 66f7d451a68b
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         0
       both:                      0
     local heads:                 1
       common:                    0
       missing:                   1
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:             32
     common:                      2
       heads:                     1
       roots:                     1
     missing:                    30
       heads:                     1
       roots:                     1
+    first undecided set:        32
+      heads:                     1
+      roots:                     1
+      common:                    2
+      missing:                  30
   common heads: 66f7d451a68b
   
   % -- a -> b set
   comparing with b
   query 1; heads
   searching for changes
   taking quick initial sample
   searching: 2 queries
   query 2; still undecided: 31, sample size is: 31
   2 total queries in *.????s (glob)
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         0
       both:                      0
     local heads:                 1
       common:                    0
       missing:                   1
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:             32
     common:                      2
       heads:                     1
       roots:                     1
     missing:                    30
       heads:                     1
       roots:                     1
+    first undecided set:        32
+      heads:                     1
+      roots:                     1
+      common:                    2
+      missing:                  30
   common heads: 66f7d451a68b
   
   % -- a -> b set (tip only)
   comparing with b
   query 1; heads
   searching for changes
   taking quick initial sample
   searching: 2 queries
   query 2; still undecided: 31, sample size is: 31
   2 total queries in *.????s (glob)
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         0
       both:                      0
     local heads:                 1
       common:                    0
       missing:                   1
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:             32
     common:                      2
       heads:                     1
       roots:                     1
     missing:                    30
       heads:                     1
       roots:                     1
+    first undecided set:        32
+      heads:                     1
+      roots:                     1
+      common:                    2
+      missing:                  30
   common heads: 66f7d451a68b
   
   % -- b -> a tree
   comparing with a
   searching for changes
   unpruned common: 66f7d451a68b
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         0
       both:                      0
     local heads:                 1
       common:                    0
       missing:                   1
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:             32
     common:                      2
       heads:                     1
       roots:                     1
     missing:                    30
       heads:                     1
       roots:                     1
+    first undecided set:        32
+      heads:                     1
+      roots:                     1
+      common:                    2
+      missing:                  30
   common heads: 66f7d451a68b
   
   % -- b -> a set
   comparing with a
   query 1; heads
   searching for changes
   taking quick initial sample
   searching: 2 queries
   query 2; still undecided: 31, sample size is: 31
   2 total queries in *.????s (glob)
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         0
       both:                      0
     local heads:                 1
       common:                    0
       missing:                   1
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:             32
     common:                      2
       heads:                     1
       roots:                     1
     missing:                    30
       heads:                     1
       roots:                     1
+    first undecided set:        32
+      heads:                     1
+      roots:                     1
+      common:                    2
+      missing:                  30
   common heads: 66f7d451a68b
   
   % -- b -> a set (tip only)
   comparing with a
   query 1; heads
   searching for changes
   taking quick initial sample
   searching: 2 queries
   query 2; still undecided: 31, sample size is: 31
   2 total queries in *.????s (glob)
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         0
       both:                      0
     local heads:                 1
       common:                    0
       missing:                   1
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:             32
     common:                      2
       heads:                     1
       roots:                     1
     missing:                    30
       heads:                     1
       roots:                     1
+    first undecided set:        32
+      heads:                     1
+      roots:                     1
+      common:                    2
+      missing:                  30
   common heads: 66f7d451a68b
 
 
 Both many new skewed:
 
   $ testdesc '-ra' '-rb' '
   > +2:f +30 :b
   > <f +50 :a'
   
   % -- a -> b tree
   comparing with b
   searching for changes
   unpruned common: 66f7d451a68b
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         0
       both:                      0
     local heads:                 1
       common:                    0
       missing:                   1
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:             52
     common:                      2
       heads:                     1
       roots:                     1
     missing:                    50
       heads:                     1
       roots:                     1
+    first undecided set:        52
+      heads:                     1
+      roots:                     1
+      common:                    2
+      missing:                  50
   common heads: 66f7d451a68b
   
   % -- a -> b set
   comparing with b
   query 1; heads
   searching for changes
   taking quick initial sample
   searching: 2 queries
   query 2; still undecided: 51, sample size is: 51
   2 total queries in *.????s (glob)
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         0
       both:                      0
     local heads:                 1
       common:                    0
       missing:                   1
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:             52
     common:                      2
       heads:                     1
       roots:                     1
     missing:                    50
       heads:                     1
       roots:                     1
+    first undecided set:        52
+      heads:                     1
+      roots:                     1
+      common:                    2
+      missing:                  50
   common heads: 66f7d451a68b
   
   % -- a -> b set (tip only)
   comparing with b
   query 1; heads
   searching for changes
   taking quick initial sample
   searching: 2 queries
   query 2; still undecided: 51, sample size is: 51
   2 total queries in *.????s (glob)
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         0
       both:                      0
     local heads:                 1
       common:                    0
       missing:                   1
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:             52
     common:                      2
       heads:                     1
       roots:                     1
     missing:                    50
       heads:                     1
       roots:                     1
+    first undecided set:        52
+      heads:                     1
+      roots:                     1
+      common:                    2
+      missing:                  50
   common heads: 66f7d451a68b
   
   % -- b -> a tree
   comparing with a
   searching for changes
   unpruned common: 66f7d451a68b
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         0
       both:                      0
     local heads:                 1
       common:                    0
       missing:                   1
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:             32
     common:                      2
       heads:                     1
       roots:                     1
     missing:                    30
       heads:                     1
       roots:                     1
+    first undecided set:        32
+      heads:                     1
+      roots:                     1
+      common:                    2
+      missing:                  30
   common heads: 66f7d451a68b
   
   % -- b -> a set
   comparing with a
   query 1; heads
   searching for changes
   taking quick initial sample
   searching: 2 queries
   query 2; still undecided: 31, sample size is: 31
   2 total queries in *.????s (glob)
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         0
       both:                      0
     local heads:                 1
       common:                    0
       missing:                   1
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:             32
     common:                      2
       heads:                     1
       roots:                     1
     missing:                    30
       heads:                     1
       roots:                     1
+    first undecided set:        32
+      heads:                     1
+      roots:                     1
+      common:                    2
+      missing:                  30
   common heads: 66f7d451a68b
   
   % -- b -> a set (tip only)
   comparing with a
   query 1; heads
   searching for changes
   taking quick initial sample
   searching: 2 queries
   query 2; still undecided: 31, sample size is: 31
   2 total queries in *.????s (glob)
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         0
       both:                      0
     local heads:                 1
       common:                    0
       missing:                   1
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:             32
     common:                      2
       heads:                     1
       roots:                     1
     missing:                    30
       heads:                     1
       roots:                     1
+    first undecided set:        32
+      heads:                     1
+      roots:                     1
+      common:                    2
+      missing:                  30
   common heads: 66f7d451a68b
 
 
 Both many new on top of long history:
 
   $ testdesc '-ra' '-rb' '
   > +1000:f +30 :b
   > <f +50 :a'
   
   % -- a -> b tree
   comparing with b
   searching for changes
   unpruned common: 7ead0cba2838
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         0
       both:                      0
     local heads:                 1
       common:                    0
       missing:                   1
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:           1050
     common:                   1000
       heads:                     1
       roots:                     1
     missing:                    50
       heads:                     1
       roots:                     1
+    first undecided set:      1050
+      heads:                     1
+      roots:                     1
+      common:                 1000
+      missing:                  50
   common heads: 7ead0cba2838
   
   % -- a -> b set
   comparing with b
   query 1; heads
   searching for changes
   taking quick initial sample
   searching: 2 queries
   query 2; still undecided: 1049, sample size is: 11
   sampling from both directions
   searching: 3 queries
   query 3; still undecided: 31, sample size is: 31
   3 total queries in *.????s (glob)
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         0
       both:                      0
     local heads:                 1
       common:                    0
       missing:                   1
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:           1050
     common:                   1000
       heads:                     1
       roots:                     1
     missing:                    50
       heads:                     1
       roots:                     1
+    first undecided set:      1050
+      heads:                     1
+      roots:                     1
+      common:                 1000
+      missing:                  50
   common heads: 7ead0cba2838
   
   % -- a -> b set (tip only)
   comparing with b
   query 1; heads
   searching for changes
   taking quick initial sample
   searching: 2 queries
   query 2; still undecided: 1049, sample size is: 11
   sampling from both directions
   searching: 3 queries
   query 3; still undecided: 31, sample size is: 31
   3 total queries in *.????s (glob)
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         0
       both:                      0
     local heads:                 1
       common:                    0
       missing:                   1
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:           1050
     common:                   1000
       heads:                     1
       roots:                     1
     missing:                    50
       heads:                     1
       roots:                     1
+    first undecided set:      1050
+      heads:                     1
+      roots:                     1
+      common:                 1000
+      missing:                  50
   common heads: 7ead0cba2838
   
   % -- b -> a tree
   comparing with a
   searching for changes
   unpruned common: 7ead0cba2838
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         0
       both:                      0
     local heads:                 1
       common:                    0
       missing:                   1
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:           1030
     common:                   1000
       heads:                     1
       roots:                     1
     missing:                    30
       heads:                     1
       roots:                     1
+    first undecided set:      1030
+      heads:                     1
+      roots:                     1
+      common:                 1000
+      missing:                  30
   common heads: 7ead0cba2838
   
   % -- b -> a set
   comparing with a
   query 1; heads
   searching for changes
   taking quick initial sample
   searching: 2 queries
   query 2; still undecided: 1029, sample size is: 11
   sampling from both directions
   searching: 3 queries
   query 3; still undecided: 15, sample size is: 15
   3 total queries in *.????s (glob)
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         0
       both:                      0
     local heads:                 1
       common:                    0
       missing:                   1
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:           1030
     common:                   1000
       heads:                     1
       roots:                     1
     missing:                    30
       heads:                     1
       roots:                     1
+    first undecided set:      1030
+      heads:                     1
+      roots:                     1
+      common:                 1000
+      missing:                  30
   common heads: 7ead0cba2838
   
   % -- b -> a set (tip only)
   comparing with a
   query 1; heads
   searching for changes
   taking quick initial sample
   searching: 2 queries
   query 2; still undecided: 1029, sample size is: 11
   sampling from both directions
   searching: 3 queries
   query 3; still undecided: 15, sample size is: 15
   3 total queries in *.????s (glob)
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         0
       both:                      0
     local heads:                 1
       common:                    0
       missing:                   1
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:           1030
     common:                   1000
       heads:                     1
       roots:                     1
     missing:                    30
       heads:                     1
       roots:                     1
+    first undecided set:      1030
+      heads:                     1
+      roots:                     1
+      common:                 1000
+      missing:                  30
   common heads: 7ead0cba2838
 
 
 One with >200 heads. We now switch to send them all in the initial roundtrip, but still do sampling for the later request.
 
   $ hg init manyheads
   $ cd manyheads
   $ echo "+300:r @a" >dagdesc
   $ echo "*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3 *r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3" >>dagdesc # 20 heads
   $ echo "*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3 *r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3" >>dagdesc # 20 heads
   $ echo "*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3 *r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3" >>dagdesc # 20 heads
   $ echo "*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3 *r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3" >>dagdesc # 20 heads
   $ echo "*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3 *r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3" >>dagdesc # 20 heads
   $ echo "*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3 *r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3" >>dagdesc # 20 heads
   $ echo "*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3 *r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3" >>dagdesc # 20 heads
   $ echo "*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3 *r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3" >>dagdesc # 20 heads
   $ echo "*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3 *r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3" >>dagdesc # 20 heads
   $ echo "*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3 *r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3" >>dagdesc # 20 heads
   $ echo "*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3 *r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3" >>dagdesc # 20 heads
   $ echo "*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3 *r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3" >>dagdesc # 20 heads
   $ echo "*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3 *r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3*r+3" >>dagdesc # 20 heads
   $ echo "@b *r+3" >>dagdesc # one more head
   $ hg debugbuilddag <dagdesc
   reading DAG from stdin
 
   $ hg heads -t --template . | wc -c
   \s*261 (re)
 
   $ hg clone -b a . a
   adding changesets
   adding manifests
   adding file changes
   added 1340 changesets with 0 changes to 0 files (+259 heads)
   new changesets 1ea73414a91b:1c51e2c80832
   updating to branch a
   0 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ hg clone -b b . b
   adding changesets
   adding manifests
   adding file changes
   added 304 changesets with 0 changes to 0 files
   new changesets 1ea73414a91b:513314ca8b3a
   updating to branch b
   0 files updated, 0 files merged, 0 files removed, 0 files unresolved
 
   $ hg -R a debugdiscovery b --debug --verbose --config progress.debug=true --config devel.discovery.randomize=false
   comparing with b
   query 1; heads
   searching for changes
   taking quick initial sample
   searching: 2 queries
   query 2; still undecided: 1080, sample size is: 100
   sampling from both directions
   searching: 3 queries
   query 3; still undecided: 980, sample size is: 200
   sampling from both directions
   searching: 4 queries
   query 4; still undecided: 497, sample size is: 210
   sampling from both directions
   searching: 5 queries
   query 5; still undecided: 285, sample size is: 220
   sampling from both directions
   searching: 6 queries
   query 6; still undecided: 63, sample size is: 63
   6 total queries in *.????s (glob)
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         0
       both:                      0
     local heads:               260
       common:                    0
       missing:                 260
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:           1340
     common:                    300
       heads:                     1
       roots:                     1
     missing:                  1040
       heads:                   260
       roots:                   260
+    first undecided set:      1340
+      heads:                   260
+      roots:                     1
+      common:                  300
+      missing:                1040
   common heads: 3ee37d65064a
   $ hg -R a debugdiscovery b --debug --verbose --config progress.debug=true --rev tip
   comparing with b
   query 1; heads
   searching for changes
   taking quick initial sample
   searching: 2 queries
   query 2; still undecided: 303, sample size is: 9
   sampling from both directions
   searching: 3 queries
   query 3; still undecided: 3, sample size is: 3
   3 total queries in *.????s (glob)
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          0
       also remote heads:         0
       both:                      0
     local heads:               260
       common:                    0
       missing:                 260
     remote heads:                1
       common:                    0
       unknown:                   1
   local changesets:           1340
     common:                    300
       heads:                     1
       roots:                     1
     missing:                  1040
       heads:                   260
       roots:                   260
+    first undecided set:      1340
+      heads:                   260
+      roots:                     1
+      common:                  300
+      missing:                1040
   common heads: 3ee37d65064a
 
 Test actual protocol when pulling one new head in addition to common heads
 
   $ hg clone -U b c
   $ hg -R c id -ir tip
   513314ca8b3a
   $ hg -R c up -qr default
   $ touch c/f
   $ hg -R c ci -Aqm "extra head"
   $ hg -R c id -i
   e64a39e7da8b
 
   $ hg serve -R c -p $HGPORT -d --pid-file=hg.pid -A access.log -E errors.log
   $ cat hg.pid >> $DAEMON_PIDS
 
   $ hg -R b incoming http://localhost:$HGPORT/ -T '{node|short}\n'
   comparing with http://localhost:$HGPORT/
   searching for changes
   e64a39e7da8b
 
   $ killdaemons.py
   $ cut -d' ' -f6- access.log | grep -v cmd=known # cmd=known uses random sampling
   "GET /?cmd=capabilities HTTP/1.1" 200 -
   "GET /?cmd=batch HTTP/1.1" 200 - x-hgarg-1:cmds=heads+%3Bknown+nodes%3D513314ca8b3ae4dac8eec56966265b00fcf866db x-hgproto-1:0.1 0.2 comp=$USUAL_COMPRESSIONS$ partial-pull
   "GET /?cmd=getbundle HTTP/1.1" 200 - x-hgarg-1:$USUAL_BUNDLE_CAPS$&cg=1&common=513314ca8b3ae4dac8eec56966265b00fcf866db&heads=e64a39e7da8b0d54bc63e81169aff001c13b3477 x-hgproto-1:0.1 0.2 comp=$USUAL_COMPRESSIONS$ partial-pull
   "GET /?cmd=listkeys HTTP/1.1" 200 - x-hgarg-1:namespace=phases x-hgproto-1:0.1 0.2 comp=$USUAL_COMPRESSIONS$ partial-pull
   $ cat errors.log
 
   $ cd ..
 
 
 Issue 4438 - test coverage for 3ef893520a85 issues.
 
   $ mkdir issue4438
   $ cd issue4438
 #if false
 generate new bundles:
   $ hg init r1
   $ for i in `"$PYTHON" $TESTDIR/seq.py 101`; do hg -R r1 up -qr null && hg -R r1 branch -q b$i && hg -R r1 ci -qmb$i; done
   $ hg clone -q r1 r2
   $ for i in `"$PYTHON" $TESTDIR/seq.py 10`; do hg -R r1 up -qr null && hg -R r1 branch -q c$i && hg -R r1 ci -qmc$i; done
   $ hg -R r2 branch -q r2change && hg -R r2 ci -qmr2change
   $ hg -R r1 bundle -qa $TESTDIR/bundles/issue4438-r1.hg
   $ hg -R r2 bundle -qa $TESTDIR/bundles/issue4438-r2.hg
 #else
 use existing bundles:
   $ hg init r1
   $ hg -R r1 -q unbundle $TESTDIR/bundles/issue4438-r1.hg
   $ hg -R r1 -q up
   $ hg init r2
   $ hg -R r2 -q unbundle $TESTDIR/bundles/issue4438-r2.hg
   $ hg -R r2 -q up
 #endif
 
 Set iteration order could cause wrong and unstable results - fixed in 73cfaa348650:
 
   $ hg -R r1 outgoing r2 -T'{rev} '
   comparing with r2
   searching for changes
   101 102 103 104 105 106 107 108 109 110  (no-eol)
 
 The case where all the 'initialsamplesize' samples already were common would
 give 'all remote heads known locally' without checking the remaining heads -
 fixed in 86c35b7ae300:
 
   $ cat >> r1/.hg/hgrc << EOF
   > [devel]
   > discovery.randomize = False
   > EOF
 
   $ hg -R r1 outgoing r2 -T'{rev} ' --config extensions.blackbox= \
   > --config blackbox.track='command commandfinish discovery'
   comparing with r2
   searching for changes
   101 102 103 104 105 106 107 108 109 110  (no-eol)
   $ hg -R r1 --config extensions.blackbox= blackbox --config blackbox.track=
   * @5d0b986a083e0d91f116de4691e2aaa54d5bbec0 (*)> serve --cmdserver chgunix * (glob) (chg !)
   * @5d0b986a083e0d91f116de4691e2aaa54d5bbec0 (*)> -R r1 outgoing r2 *-T{rev} * --config *extensions.blackbox=* (glob)
   * @5d0b986a083e0d91f116de4691e2aaa54d5bbec0 (*)> found 101 common and 1 unknown server heads, 1 roundtrips in *.????s (glob)
   * @5d0b986a083e0d91f116de4691e2aaa54d5bbec0 (*)> -R r1 outgoing r2 *-T{rev} * --config *extensions.blackbox=* exited 0 after *.?? seconds (glob)
   $ cd ..
 
 Even if the set of revs to discover is restricted, unrelated revs may be
 returned as common heads.
 
   $ mkdir ancestorsof
   $ cd ancestorsof
   $ hg init a
   $ hg clone a b -q
   $ cd b
   $ hg debugbuilddag '.:root *root *root'
   $ hg log -G -T '{node|short}'
   o  fa942426a6fd
   |
   | o  66f7d451a68b
   |/
   o  1ea73414a91b
   
   $ hg push -r 66f7d451a68b -q
   $ hg debugdiscovery --verbose --rev fa942426a6fd
   comparing with $TESTTMP/ancestorsof/a
   searching for changes
   elapsed time:  * seconds (glob)
   heads summary:
     total common heads:          1
       also local heads:          1
       also remote heads:         1
       both:                      1
     local heads:                 2
       common:                    1
       missing:                   1
     remote heads:                1
       common:                    1
       unknown:                   0
   local changesets:              3
     common:                      2
       heads:                     1
       roots:                     1
     missing:                     1
       heads:                     1
       roots:                     1
+    first undecided set:         1
+      heads:                     1
+      roots:                     1
+      common:                    0
+      missing:                   1
   common heads: 66f7d451a68b