clonebundles: support for seeding clones from pre-generated bundles

Cloning can be an expensive operation for servers because the server
generates a bundle from existing repository data at request time. For
a large repository like mozilla-central, this consumes 4+ minutes
of CPU time on the server. It also results in significant network
utilization. Multiplied by hundreds or even thousands of clients and
the ensuing load can result in difficulties scaling the Mercurial server.

Despite generation of bundles being deterministic until the next
changeset is added, the generation of bundles to service a clone request
is not cached. Each clone thus performs redundant work. This is
wasteful.

This patch introduces the "clonebundles" extension and related
client-side functionality to help alleviate this deficiency. The
client-side feature is behind an experimental flag and is not enabled by
default.

It works as follows:

1) Server operator generates a bundle and makes it available on a
   server (likely HTTP).
2) Server operator defines the URL of a bundle file in a
   .hg/clonebundles.manifest file.
3) Client `hg clone`ing sees the server is advertising bundle URLs.
4) Client fetches and applies the advertised bundle.
5) Client performs equivalent of `hg pull` to fetch changes made since
   the bundle was created.

Essentially, the server performs the expensive work of generating a
bundle once and all subsequent clones fetch a static file from
somewhere. Scaling static file serving is a much more manageable
problem than scaling a Python application like Mercurial. Assuming your
repository grows less than 1% per day, the end result is 99+% of CPU
and network load from clones is eliminated, allowing Mercurial servers
to scale more easily. Serving static files also means data can be
transferred to clients as fast as they can consume it, rather than as
fast as servers can generate it. This makes clones faster.

Mozilla has implemented similar functionality of this patch on
hg.mozilla.org using a custom extension. We are hosting bundle files in
Amazon S3 and CloudFront (a CDN) and have successfully offloaded
>1 TB/day in data transfer from hg.mozilla.org, freeing up significant
bandwidth and CPU resources. The positive impact has been stellar and
I believe it has proved its value to be included in Mercurial core. I
feel it is important for the client-side support to be enabled in core
by default because it means that clients will get faster, more reliable
clones and will enable server operators to reduce load without
requiring any client-side configuration changes (assuming clients are
up to date, of course).

The scope of this feature is narrowly and specifically tailored to
cloning, despite "serve pulls from pre-generated bundles" being a valid
and useful feature. I would eventually like for Mercurial servers to
support transferring *all* repository data via statically hosted files.
You could imagine a server that siphons all pushed data to bundle files
and instructs clients to apply a stream of bundles to reconstruct all
repository data. This feature, while useful and powerful, is
significantly more work to implement because it requires the server
component have awareness of discovery and a mapping of which changesets
are in which files. Full, clone bundles, by contrast, are much simpler.

The wire protocol command is named "clonebundles" instead of something
more generic like "staticbundles" to leave the door open for a new, more
powerful and more generic server-side component with minimal backwards
compatibility implications. The name "bundleclone" is used by Mozilla's
extension and would cause problems since there are subtle differences
in Mozilla's extension.

Mozilla's experience with this idea has taught us that some form of
"content negotiation" is required. Not all clients will support all
bundle formats or even URLs (advanced TLS requirements, etc). To ensure
the highest uptake possible, a server needs to advertise multiple
versions of bundles and clients need to be able to choose the most
appropriate from that list one. The "attributes" in each
server-advertised entry facilitate this filtering and sorting. Their
use will become apparent in subsequent patches.

Initial inspiration and credit for the idea of cloning from static files
belongs to Augie Fackler and his "lookaside clone" extension proof of
concept.

hgext/clonebundles.py

@@ -0,0 +1,69
+# This software may be used and distributed according to the terms of the
+# GNU General Public License version 2 or any later version.
+
+"""server side extension to advertise pre-generated bundles to seed clones.
+
+The extension essentially serves the content of a .hg/clonebundles.manifest
+file to clients that request it.
+
+The clonebundles.manifest file contains a list of URLs and attributes. URLs
+hold pre-generated bundles that a client fetches and applies. After applying
+the pre-generated bundle, the client will connect back to the original server
+and pull data not in the pre-generated bundle.
+
+Manifest File Format:
+
+The manifest file contains a newline (\n) delimited list of entries.
+
+Each line in this file defines an available bundle. Lines have the format:
+
+    <URL> [<key>=<value]
+
+That is, a URL followed by extra metadata describing it. Metadata keys and
+values should be URL encoded.
+
+This metadata is optional. It is up to server operators to populate this
+metadata.
+
+Keys in UPPERCASE are reserved for use by Mercurial. All non-uppercase keys
+can be used by site installations.
+
+The server operator is responsible for generating the bundle manifest file.
+
+Metadata Attributes:
+
+TBD
+"""
+
+from mercurial import (
+    extensions,
+    wireproto,
+)
+
+testedwith = 'internal'
+
+def capabilities(orig, repo, proto):
+    caps = orig(repo, proto)
+
+    # Only advertise if a manifest exists. This does add some I/O to requests.
+    # But this should be cheaper than a wasted network round trip due to
+    # missing file.
+    if repo.opener.exists('clonebundles.manifest'):
+        caps.append('clonebundles')
+
+    return caps
+
[e-mail]('clonebundles', '')
+def bundles(repo, proto):
+    """Server command for returning info for available bundles to seed clones.
+
+    Clients will parse this response and determine what bundle to fetch.
+
+    Other extensions may wrap this command to filter or dynamically emit
+    data depending on the request. e.g. you could advertise URLs for
+    the closest data center given the client's IP address.
+    """
+    return repo.opener.tryread('clonebundles.manifest')
+
+def extsetup(ui):
+    extensions.wrapfunction(wireproto, '_capabilities', capabilities)

tests/test-clonebundles.t

@@ -0,0 +1,143
+Set up a server
+
+  $ hg init server
+  $ cd server
+  $ cat >> .hg/hgrc << EOF
+  > [extensions]
+  > clonebundles =
+  > EOF
+
+  $ touch foo
+  $ hg -q commit -A -m 'add foo'
+  $ touch bar
+  $ hg -q commit -A -m 'add bar'
+
+  $ hg serve -d -p $HGPORT --pid-file hg.pid --accesslog access.log
+  $ cat hg.pid >> $DAEMON_PIDS
+  $ cd ..
+
+Feature disabled by default
+(client should not request manifest)
+
+  $ hg clone -U http://localhost:$HGPORT feature-disabled
+  requesting all changes
+  adding changesets
+  adding manifests
+  adding file changes
+  added 2 changesets with 2 changes to 2 files
+
+  $ cat server/access.log
+  * - - [*] "GET /?cmd=capabilities HTTP/1.1" 200 - (glob)
+  * - - [*] "GET /?cmd=batch HTTP/1.1" 200 - x-hgarg-1:cmds=heads+%3Bknown+nodes%3D (glob)
+  * - - [*] "GET /?cmd=getbundle HTTP/1.1" 200 - x-hgarg-1:bundlecaps=HG20%2Cbundle2%3DHG20%250Achangegroup%253D01%252C02%250Adigests%253Dmd5%252Csha1%252Csha512%250Aerror%253Dabort%252Cunsupportedcontent%252Cpushraced%252Cpushkey%250Ahgtagsfnodes%250Alistkeys%250Apushkey%250Aremote-changegroup%253Dhttp%252Chttps&cg=1&common=0000000000000000000000000000000000000000&heads=aaff8d2ffbbf07a46dd1f05d8ae7877e3f56e2a2&listkeys=phase%2Cbookmarks (glob)
+  * - - [*] "GET /?cmd=listkeys HTTP/1.1" 200 - x-hgarg-1:namespace=phases (glob)
+
+  $ cat >> $HGRCPATH << EOF
+  > [experimental]
+  > clonebundles = true
+  > EOF
+
+Missing manifest should not result in server lookup
+
+  $ hg --verbose clone -U http://localhost:$HGPORT no-manifest
+  requesting all changes
+  adding changesets
+  adding manifests
+  adding file changes
+  added 2 changesets with 2 changes to 2 files
+
+  $ tail -4 server/access.log
+  * - - [*] "GET /?cmd=capabilities HTTP/1.1" 200 - (glob)
+  * - - [*] "GET /?cmd=batch HTTP/1.1" 200 - x-hgarg-1:cmds=heads+%3Bknown+nodes%3D (glob)
+  * - - [*] "GET /?cmd=getbundle HTTP/1.1" 200 - x-hgarg-1:bundlecaps=HG20%2Cbundle2%3DHG20%250Achangegroup%253D01%252C02%250Adigests%253Dmd5%252Csha1%252Csha512%250Aerror%253Dabort%252Cunsupportedcontent%252Cpushraced%252Cpushkey%250Ahgtagsfnodes%250Alistkeys%250Apushkey%250Aremote-changegroup%253Dhttp%252Chttps&cg=1&common=0000000000000000000000000000000000000000&heads=aaff8d2ffbbf07a46dd1f05d8ae7877e3f56e2a2&listkeys=phase%2Cbookmarks (glob)
+  * - - [*] "GET /?cmd=listkeys HTTP/1.1" 200 - x-hgarg-1:namespace=phases (glob)
+
+Empty manifest file results in retrieval
+(the extension only checks if the manifest file exists)
+
+  $ touch server/.hg/clonebundles.manifest
+  $ hg --verbose clone -U http://localhost:$HGPORT empty-manifest
+  no clone bundles available on remote; falling back to regular clone
+  requesting all changes
+  adding changesets
+  adding manifests
+  adding file changes
+  added 2 changesets with 2 changes to 2 files
+
+Manifest file with invalid URL aborts
+
+  $ echo 'http://does.not.exist/bundle.hg' > server/.hg/clonebundles.manifest
+  $ hg clone http://localhost:$HGPORT 404-url
+  applying clone bundle from http://does.not.exist/bundle.hg
+  error fetching bundle: [Errno -2] Name or service not known
+  abort: error applying bundle
+  (consider contacting the server operator if this error persists)
+  [255]
+
+Server is not running aborts
+
+  $ echo "http://localhost:$HGPORT1/bundle.hg" > server/.hg/clonebundles.manifest
+  $ hg clone http://localhost:$HGPORT server-not-runner
+  applying clone bundle from http://localhost:$HGPORT1/bundle.hg
+  error fetching bundle: [Errno 111] Connection refused
+  abort: error applying bundle
+  (consider contacting the server operator if this error persists)
+  [255]
+
+Server returns 404
+
+  $ python $TESTDIR/dumbhttp.py -p $HGPORT1 --pid http.pid
+  $ cat http.pid >> $DAEMON_PIDS
+  $ hg clone http://localhost:$HGPORT running-404
+  applying clone bundle from http://localhost:$HGPORT1/bundle.hg
+  HTTP error fetching bundle: HTTP Error 404: File not found
+  abort: error applying bundle
+  (consider contacting the server operator if this error persists)
+  [255]
+
+We can override failure to fall back to regular clone
+
+  $ hg --config ui.clonebundlefallback=true clone -U http://localhost:$HGPORT 404-fallback
+  applying clone bundle from http://localhost:$HGPORT1/bundle.hg
+  HTTP error fetching bundle: HTTP Error 404: File not found
+  falling back to normal clone
+  requesting all changes
+  adding changesets
+  adding manifests
+  adding file changes
+  added 2 changesets with 2 changes to 2 files
+
+Bundle with partial content works
+
+  $ hg -R server bundle --type gzip --base null -r 53245c60e682 partial.hg
+  1 changesets found
+
+  $ echo "http://localhost:$HGPORT1/partial.hg" > server/.hg/clonebundles.manifest
+  $ hg clone -U http://localhost:$HGPORT partial-bundle
+  applying clone bundle from http://localhost:$HGPORT1/partial.hg
+  adding changesets
+  adding manifests
+  adding file changes
+  added 1 changesets with 1 changes to 1 files
+  finished applying clone bundle
+  searching for changes
+  adding changesets
+  adding manifests
+  adding file changes
+  added 1 changesets with 1 changes to 1 files
+
+Bundle with full content works
+
+  $ hg -R server bundle --type gzip --base null -r tip full.hg
+  2 changesets found
+
+  $ echo "http://localhost:$HGPORT1/full.hg" > server/.hg/clonebundles.manifest
+  $ hg clone -U http://localhost:$HGPORT full-bundle
+  applying clone bundle from http://localhost:$HGPORT1/full.hg
+  adding changesets
+  adding manifests
+  adding file changes
+  added 2 changesets with 2 changes to 2 files
+  finished applying clone bundle
+  searching for changes
+  no changes found

mercurial/exchange.py

@@ -1,1501 +1,1590
 # exchange.py - utility to exchange data between repos.
 #
 # Copyright 2005-2007 Matt Mackall <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
 from i18n import _
 from node import hex, nullid
-import errno, urllib
+import errno, urllib, urllib2
 import util, scmutil, changegroup, base85, error
 import discovery, phases, obsolete, bookmarks as bookmod, bundle2, pushkey
 import lock as lockmod
 import streamclone
 import tags
+import url as urlmod
 
 def readbundle(ui, fh, fname, vfs=None):
     header = changegroup.readexactly(fh, 4)
 
     alg = None
     if not fname:
         fname = "stream"
         if not header.startswith('HG') and header.startswith('\0'):
             fh = changegroup.headerlessfixup(fh, header)
             header = "HG10"
             alg = 'UN'
     elif vfs:
         fname = vfs.join(fname)
 
     magic, version = header[0:2], header[2:4]
 
     if magic != 'HG':
         raise error.Abort(_('%s: not a Mercurial bundle') % fname)
     if version == '10':
         if alg is None:
             alg = changegroup.readexactly(fh, 2)
         return changegroup.cg1unpacker(fh, alg)
     elif version.startswith('2'):
         return bundle2.getunbundler(ui, fh, magicstring=magic + version)
     else:
         raise error.Abort(_('%s: unknown bundle version %s') % (fname, version))
 
 def buildobsmarkerspart(bundler, markers):
     """add an obsmarker part to the bundler with <markers>
 
     No part is created if markers is empty.
     Raises ValueError if the bundler doesn't support any known obsmarker format.
     """
     if markers:
         remoteversions = bundle2.obsmarkersversion(bundler.capabilities)
         version = obsolete.commonversion(remoteversions)
         if version is None:
             raise ValueError('bundler do not support common obsmarker format')
         stream = obsolete.encodemarkers(markers, True, version=version)
         return bundler.newpart('obsmarkers', data=stream)
     return None
 
 def _canusebundle2(op):
     """return true if a pull/push can use bundle2
 
     Feel free to nuke this function when we drop the experimental option"""
     return (op.repo.ui.configbool('experimental', 'bundle2-exp', True)
             and op.remote.capable('bundle2'))
 
 
 class pushoperation(object):
     """A object that represent a single push operation
 
     It purpose is to carry push related state and very common operation.
 
     A new should be created at the beginning of each push and discarded
     afterward.
     """
 
     def __init__(self, repo, remote, force=False, revs=None, newbranch=False,
                  bookmarks=()):
         # repo we push from
         self.repo = repo
         self.ui = repo.ui
         # repo we push to
         self.remote = remote
         # force option provided
         self.force = force
         # revs to be pushed (None is "all")
         self.revs = revs
         # bookmark explicitly pushed
         self.bookmarks = bookmarks
         # allow push of new branch
         self.newbranch = newbranch
         # did a local lock get acquired?
         self.locallocked = None
         # step already performed
         # (used to check what steps have been already performed through bundle2)
         self.stepsdone = set()
         # Integer version of the changegroup push result
         # - None means nothing to push
         # - 0 means HTTP error
         # - 1 means we pushed and remote head count is unchanged *or*
         #   we have outgoing changesets but refused to push
         # - other values as described by addchangegroup()
         self.cgresult = None
         # Boolean value for the bookmark push
         self.bkresult = None
         # discover.outgoing object (contains common and outgoing data)
         self.outgoing = None
         # all remote heads before the push
         self.remoteheads = None
         # testable as a boolean indicating if any nodes are missing locally.
         self.incoming = None
         # phases changes that must be pushed along side the changesets
         self.outdatedphases = None
         # phases changes that must be pushed if changeset push fails
         self.fallbackoutdatedphases = None
         # outgoing obsmarkers
         self.outobsmarkers = set()
         # outgoing bookmarks
         self.outbookmarks = []
         # transaction manager
         self.trmanager = None
         # map { pushkey partid -> callback handling failure}
         # used to handle exception from mandatory pushkey part failure
         self.pkfailcb = {}
 
     @util.propertycache
     def futureheads(self):
         """future remote heads if the changeset push succeeds"""
         return self.outgoing.missingheads
 
     @util.propertycache
     def fallbackheads(self):
         """future remote heads if the changeset push fails"""
         if self.revs is None:
             # not target to push, all common are relevant
             return self.outgoing.commonheads
         unfi = self.repo.unfiltered()
         # I want cheads = heads(::missingheads and ::commonheads)
         # (missingheads is revs with secret changeset filtered out)
         #
         # This can be expressed as:
         #     cheads = ( (missingheads and ::commonheads)
         #              + (commonheads and ::missingheads))"
         #              )
         #
         # while trying to push we already computed the following:
         #     common = (::commonheads)
         #     missing = ((commonheads::missingheads) - commonheads)
         #
         # We can pick:
         # * missingheads part of common (::commonheads)
         common = self.outgoing.common
         nm = self.repo.changelog.nodemap
         cheads = [node for node in self.revs if nm[node] in common]
         # and
         # * commonheads parents on missing
         revset = unfi.set('%ln and parents(roots(%ln))',
                          self.outgoing.commonheads,
                          self.outgoing.missing)
         cheads.extend(c.node() for c in revset)
         return cheads
 
     @property
     def commonheads(self):
         """set of all common heads after changeset bundle push"""
         if self.cgresult:
             return self.futureheads
         else:
             return self.fallbackheads
 
 # mapping of message used when pushing bookmark
 bookmsgmap = {'update': (_("updating bookmark %s\n"),
                          _('updating bookmark %s failed!\n')),
               'export': (_("exporting bookmark %s\n"),
                          _('exporting bookmark %s failed!\n')),
               'delete': (_("deleting remote bookmark %s\n"),
                          _('deleting remote bookmark %s failed!\n')),
               }
 
 
 def push(repo, remote, force=False, revs=None, newbranch=False, bookmarks=()):
     '''Push outgoing changesets (limited by revs) from a local
     repository to remote. Return an integer:
       - None means nothing to push
       - 0 means HTTP error
       - 1 means we pushed and remote head count is unchanged *or*
         we have outgoing changesets but refused to push
       - other values as described by addchangegroup()
     '''
     pushop = pushoperation(repo, remote, force, revs, newbranch, bookmarks)
     if pushop.remote.local():
         missing = (set(pushop.repo.requirements)
                    - pushop.remote.local().supported)
         if missing:
             msg = _("required features are not"
                     " supported in the destination:"
                     " %s") % (', '.join(sorted(missing)))
             raise error.Abort(msg)
 
     # there are two ways to push to remote repo:
     #
     # addchangegroup assumes local user can lock remote
     # repo (local filesystem, old ssh servers).
     #
     # unbundle assumes local user cannot lock remote repo (new ssh
     # servers, http servers).
 
     if not pushop.remote.canpush():
         raise error.Abort(_("destination does not support push"))
     # get local lock as we might write phase data
     localwlock = locallock = None
     try:
         # bundle2 push may receive a reply bundle touching bookmarks or other
         # things requiring the wlock. Take it now to ensure proper ordering.
         maypushback = pushop.ui.configbool('experimental', 'bundle2.pushback')
         if _canusebundle2(pushop) and maypushback:
             localwlock = pushop.repo.wlock()
         locallock = pushop.repo.lock()
         pushop.locallocked = True
     except IOError as err:
         pushop.locallocked = False
         if err.errno != errno.EACCES:
             raise
         # source repo cannot be locked.
         # We do not abort the push, but just disable the local phase
         # synchronisation.
         msg = 'cannot lock source repository: %s\n' % err
         pushop.ui.debug(msg)
     try:
         if pushop.locallocked:
             pushop.trmanager = transactionmanager(repo,
                                                   'push-response',
                                                   pushop.remote.url())
         pushop.repo.checkpush(pushop)
         lock = None
         unbundle = pushop.remote.capable('unbundle')
         if not unbundle:
             lock = pushop.remote.lock()
         try:
             _pushdiscovery(pushop)
             if _canusebundle2(pushop):
                 _pushbundle2(pushop)
             _pushchangeset(pushop)
             _pushsyncphase(pushop)
             _pushobsolete(pushop)
             _pushbookmark(pushop)
         finally:
             if lock is not None:
                 lock.release()
         if pushop.trmanager:
             pushop.trmanager.close()
     finally:
         if pushop.trmanager:
             pushop.trmanager.release()
         if locallock is not None:
             locallock.release()
         if localwlock is not None:
             localwlock.release()
 
     return pushop
 
 # list of steps to perform discovery before push
 pushdiscoveryorder = []
 
 # Mapping between step name and function
 #
 # This exists to help extensions wrap steps if necessary
 pushdiscoverymapping = {}
 
 def pushdiscovery(stepname):
     """decorator for function performing discovery before push
 
     The function is added to the step -> function mapping and appended to the
     list of steps.  Beware that decorated function will be added in order (this
     may matter).
 
     You can only use this decorator for a new step, if you want to wrap a step
     from an extension, change the pushdiscovery dictionary directly."""
     def dec(func):
         assert stepname not in pushdiscoverymapping
         pushdiscoverymapping[stepname] = func
         pushdiscoveryorder.append(stepname)
         return func
     return dec
 
 def _pushdiscovery(pushop):
     """Run all discovery steps"""
     for stepname in pushdiscoveryorder:
         step = pushdiscoverymapping[stepname]
         step(pushop)
 
 @pushdiscovery('changeset')
 def _pushdiscoverychangeset(pushop):
     """discover the changeset that need to be pushed"""
     fci = discovery.findcommonincoming
     commoninc = fci(pushop.repo, pushop.remote, force=pushop.force)
     common, inc, remoteheads = commoninc
     fco = discovery.findcommonoutgoing
     outgoing = fco(pushop.repo, pushop.remote, onlyheads=pushop.revs,
                    commoninc=commoninc, force=pushop.force)
     pushop.outgoing = outgoing
     pushop.remoteheads = remoteheads
     pushop.incoming = inc
 
 @pushdiscovery('phase')
 def _pushdiscoveryphase(pushop):
     """discover the phase that needs to be pushed
 
     (computed for both success and failure case for changesets push)"""
     outgoing = pushop.outgoing
     unfi = pushop.repo.unfiltered()
     remotephases = pushop.remote.listkeys('phases')
     publishing = remotephases.get('publishing', False)
     if (pushop.ui.configbool('ui', '_usedassubrepo', False)
         and remotephases    # server supports phases
         and not pushop.outgoing.missing # no changesets to be pushed
         and publishing):
         # When:
         # - this is a subrepo push
         # - and remote support phase
         # - and no changeset are to be pushed
         # - and remote is publishing
         # We may be in issue 3871 case!
         # We drop the possible phase synchronisation done by
         # courtesy to publish changesets possibly locally draft
         # on the remote.
         remotephases = {'publishing': 'True'}
     ana = phases.analyzeremotephases(pushop.repo,
                                      pushop.fallbackheads,
                                      remotephases)
     pheads, droots = ana
     extracond = ''
     if not publishing:
         extracond = ' and public()'
     revset = 'heads((%%ln::%%ln) %s)' % extracond
     # Get the list of all revs draft on remote by public here.
     # XXX Beware that revset break if droots is not strictly
     # XXX root we may want to ensure it is but it is costly
     fallback = list(unfi.set(revset, droots, pushop.fallbackheads))
     if not outgoing.missing:
         future = fallback
     else:
         # adds changeset we are going to push as draft
         #
         # should not be necessary for publishing server, but because of an
         # issue fixed in xxxxx we have to do it anyway.
         fdroots = list(unfi.set('roots(%ln  + %ln::)',
                        outgoing.missing, droots))
         fdroots = [f.node() for f in fdroots]
         future = list(unfi.set(revset, fdroots, pushop.futureheads))
     pushop.outdatedphases = future
     pushop.fallbackoutdatedphases = fallback
 
 @pushdiscovery('obsmarker')
 def _pushdiscoveryobsmarkers(pushop):
     if (obsolete.isenabled(pushop.repo, obsolete.exchangeopt)
         and pushop.repo.obsstore
         and 'obsolete' in pushop.remote.listkeys('namespaces')):
         repo = pushop.repo
         # very naive computation, that can be quite expensive on big repo.
         # However: evolution is currently slow on them anyway.
         nodes = (c.node() for c in repo.set('::%ln', pushop.futureheads))
         pushop.outobsmarkers = pushop.repo.obsstore.relevantmarkers(nodes)
 
 @pushdiscovery('bookmarks')
 def _pushdiscoverybookmarks(pushop):
     ui = pushop.ui
     repo = pushop.repo.unfiltered()
     remote = pushop.remote
     ui.debug("checking for updated bookmarks\n")
     ancestors = ()
     if pushop.revs:
         revnums = map(repo.changelog.rev, pushop.revs)
         ancestors = repo.changelog.ancestors(revnums, inclusive=True)
     remotebookmark = remote.listkeys('bookmarks')
 
     explicit = set(pushop.bookmarks)
 
     comp = bookmod.compare(repo, repo._bookmarks, remotebookmark, srchex=hex)
     addsrc, adddst, advsrc, advdst, diverge, differ, invalid, same = comp
     for b, scid, dcid in advsrc:
         if b in explicit:
             explicit.remove(b)
         if not ancestors or repo[scid].rev() in ancestors:
             pushop.outbookmarks.append((b, dcid, scid))
     # search added bookmark
     for b, scid, dcid in addsrc:
         if b in explicit:
             explicit.remove(b)
             pushop.outbookmarks.append((b, '', scid))
     # search for overwritten bookmark
     for b, scid, dcid in advdst + diverge + differ:
         if b in explicit:
             explicit.remove(b)
             pushop.outbookmarks.append((b, dcid, scid))
     # search for bookmark to delete
     for b, scid, dcid in adddst:
         if b in explicit:
             explicit.remove(b)
             # treat as "deleted locally"
             pushop.outbookmarks.append((b, dcid, ''))
     # identical bookmarks shouldn't get reported
     for b, scid, dcid in same:
         if b in explicit:
             explicit.remove(b)
 
     if explicit:
         explicit = sorted(explicit)
         # we should probably list all of them
         ui.warn(_('bookmark %s does not exist on the local '
                   'or remote repository!\n') % explicit[0])
         pushop.bkresult = 2
 
     pushop.outbookmarks.sort()
 
 def _pushcheckoutgoing(pushop):
     outgoing = pushop.outgoing
     unfi = pushop.repo.unfiltered()
     if not outgoing.missing:
         # nothing to push
         scmutil.nochangesfound(unfi.ui, unfi, outgoing.excluded)
         return False
     # something to push
     if not pushop.force:
         # if repo.obsstore == False --> no obsolete
         # then, save the iteration
         if unfi.obsstore:
             # this message are here for 80 char limit reason
             mso = _("push includes obsolete changeset: %s!")
             mst = {"unstable": _("push includes unstable changeset: %s!"),
                    "bumped": _("push includes bumped changeset: %s!"),
                    "divergent": _("push includes divergent changeset: %s!")}
             # If we are to push if there is at least one
             # obsolete or unstable changeset in missing, at
             # least one of the missinghead will be obsolete or
             # unstable. So checking heads only is ok
             for node in outgoing.missingheads:
                 ctx = unfi[node]
                 if ctx.obsolete():
                     raise error.Abort(mso % ctx)
                 elif ctx.troubled():
                     raise error.Abort(mst[ctx.troubles()[0]] % ctx)
 
         # internal config: bookmarks.pushing
         newbm = pushop.ui.configlist('bookmarks', 'pushing')
         discovery.checkheads(unfi, pushop.remote, outgoing,
                              pushop.remoteheads,
                              pushop.newbranch,
                              bool(pushop.incoming),
                              newbm)
     return True
 
 # List of names of steps to perform for an outgoing bundle2, order matters.
 b2partsgenorder = []
 
 # Mapping between step name and function
 #
 # This exists to help extensions wrap steps if necessary
 b2partsgenmapping = {}
 
 def b2partsgenerator(stepname, idx=None):
     """decorator for function generating bundle2 part
 
     The function is added to the step -> function mapping and appended to the
     list of steps.  Beware that decorated functions will be added in order
     (this may matter).
 
     You can only use this decorator for new steps, if you want to wrap a step
     from an extension, attack the b2partsgenmapping dictionary directly."""
     def dec(func):
         assert stepname not in b2partsgenmapping
         b2partsgenmapping[stepname] = func
         if idx is None:
             b2partsgenorder.append(stepname)
         else:
             b2partsgenorder.insert(idx, stepname)
         return func
     return dec
 
 def _pushb2ctxcheckheads(pushop, bundler):
     """Generate race condition checking parts
 
     Exists as an indepedent function to aid extensions
     """
     if not pushop.force:
         bundler.newpart('check:heads', data=iter(pushop.remoteheads))
 
 @b2partsgenerator('changeset')
 def _pushb2ctx(pushop, bundler):
     """handle changegroup push through bundle2
 
     addchangegroup result is stored in the ``pushop.cgresult`` attribute.
     """
     if 'changesets' in pushop.stepsdone:
         return
     pushop.stepsdone.add('changesets')
     # Send known heads to the server for race detection.
     if not _pushcheckoutgoing(pushop):
         return
     pushop.repo.prepushoutgoinghooks(pushop.repo,
                                      pushop.remote,
                                      pushop.outgoing)
 
     _pushb2ctxcheckheads(pushop, bundler)
 
     b2caps = bundle2.bundle2caps(pushop.remote)
     version = None
     cgversions = b2caps.get('changegroup')
     if not cgversions:  # 3.1 and 3.2 ship with an empty value
         cg = changegroup.getlocalchangegroupraw(pushop.repo, 'push',
                                                 pushop.outgoing)
     else:
         cgversions = [v for v in cgversions if v in changegroup.packermap]
         if not cgversions:
             raise ValueError(_('no common changegroup version'))
         version = max(cgversions)
         cg = changegroup.getlocalchangegroupraw(pushop.repo, 'push',
                                                 pushop.outgoing,
                                                 version=version)
     cgpart = bundler.newpart('changegroup', data=cg)
     if version is not None:
         cgpart.addparam('version', version)
     def handlereply(op):
         """extract addchangegroup returns from server reply"""
         cgreplies = op.records.getreplies(cgpart.id)
         assert len(cgreplies['changegroup']) == 1
         pushop.cgresult = cgreplies['changegroup'][0]['return']
     return handlereply
 
 @b2partsgenerator('phase')
 def _pushb2phases(pushop, bundler):
     """handle phase push through bundle2"""
     if 'phases' in pushop.stepsdone:
         return
     b2caps = bundle2.bundle2caps(pushop.remote)
     if not 'pushkey' in b2caps:
         return
     pushop.stepsdone.add('phases')
     part2node = []
 
     def handlefailure(pushop, exc):
         targetid = int(exc.partid)
         for partid, node in part2node:
             if partid == targetid:
                 raise error.Abort(_('updating %s to public failed') % node)
 
     enc = pushkey.encode
     for newremotehead in pushop.outdatedphases:
         part = bundler.newpart('pushkey')
         part.addparam('namespace', enc('phases'))
         part.addparam('key', enc(newremotehead.hex()))
         part.addparam('old', enc(str(phases.draft)))
         part.addparam('new', enc(str(phases.public)))
         part2node.append((part.id, newremotehead))
         pushop.pkfailcb[part.id] = handlefailure
 
     def handlereply(op):
         for partid, node in part2node:
             partrep = op.records.getreplies(partid)
             results = partrep['pushkey']
             assert len(results) <= 1
             msg = None
             if not results:
                 msg = _('server ignored update of %s to public!\n') % node
             elif not int(results[0]['return']):
                 msg = _('updating %s to public failed!\n') % node
             if msg is not None:
                 pushop.ui.warn(msg)
     return handlereply
 
 @b2partsgenerator('obsmarkers')
 def _pushb2obsmarkers(pushop, bundler):
     if 'obsmarkers' in pushop.stepsdone:
         return
     remoteversions = bundle2.obsmarkersversion(bundler.capabilities)
     if obsolete.commonversion(remoteversions) is None:
         return
     pushop.stepsdone.add('obsmarkers')
     if pushop.outobsmarkers:
         markers = sorted(pushop.outobsmarkers)
         buildobsmarkerspart(bundler, markers)
 
 @b2partsgenerator('bookmarks')
 def _pushb2bookmarks(pushop, bundler):
     """handle bookmark push through bundle2"""
     if 'bookmarks' in pushop.stepsdone:
         return
     b2caps = bundle2.bundle2caps(pushop.remote)
     if 'pushkey' not in b2caps:
         return
     pushop.stepsdone.add('bookmarks')
     part2book = []
     enc = pushkey.encode
 
     def handlefailure(pushop, exc):
         targetid = int(exc.partid)
         for partid, book, action in part2book:
             if partid == targetid:
                 raise error.Abort(bookmsgmap[action][1].rstrip() % book)
         # we should not be called for part we did not generated
         assert False
 
     for book, old, new in pushop.outbookmarks:
         part = bundler.newpart('pushkey')
         part.addparam('namespace', enc('bookmarks'))
         part.addparam('key', enc(book))
         part.addparam('old', enc(old))
         part.addparam('new', enc(new))
         action = 'update'
         if not old:
             action = 'export'
         elif not new:
             action = 'delete'
         part2book.append((part.id, book, action))
         pushop.pkfailcb[part.id] = handlefailure
 
     def handlereply(op):
         ui = pushop.ui
         for partid, book, action in part2book:
             partrep = op.records.getreplies(partid)
             results = partrep['pushkey']
             assert len(results) <= 1
             if not results:
                 pushop.ui.warn(_('server ignored bookmark %s update\n') % book)
             else:
                 ret = int(results[0]['return'])
                 if ret:
                     ui.status(bookmsgmap[action][0] % book)
                 else:
                     ui.warn(bookmsgmap[action][1] % book)
                     if pushop.bkresult is not None:
                         pushop.bkresult = 1
     return handlereply
 
 
 def _pushbundle2(pushop):
     """push data to the remote using bundle2
 
     The only currently supported type of data is changegroup but this will
     evolve in the future."""
     bundler = bundle2.bundle20(pushop.ui, bundle2.bundle2caps(pushop.remote))
     pushback = (pushop.trmanager
                 and pushop.ui.configbool('experimental', 'bundle2.pushback'))
 
     # create reply capability
     capsblob = bundle2.encodecaps(bundle2.getrepocaps(pushop.repo,
                                                       allowpushback=pushback))
     bundler.newpart('replycaps', data=capsblob)
     replyhandlers = []
     for partgenname in b2partsgenorder:
         partgen = b2partsgenmapping[partgenname]
         ret = partgen(pushop, bundler)
         if callable(ret):
             replyhandlers.append(ret)
     # do not push if nothing to push
     if bundler.nbparts <= 1:
         return
     stream = util.chunkbuffer(bundler.getchunks())
     try:
         try:
             reply = pushop.remote.unbundle(stream, ['force'], 'push')
         except error.BundleValueError as exc:
             raise error.Abort('missing support for %s' % exc)
         try:
             trgetter = None
             if pushback:
                 trgetter = pushop.trmanager.transaction
             op = bundle2.processbundle(pushop.repo, reply, trgetter)
         except error.BundleValueError as exc:
             raise error.Abort('missing support for %s' % exc)
     except error.PushkeyFailed as exc:
         partid = int(exc.partid)
         if partid not in pushop.pkfailcb:
             raise
         pushop.pkfailcb[partid](pushop, exc)
     for rephand in replyhandlers:
         rephand(op)
 
 def _pushchangeset(pushop):
     """Make the actual push of changeset bundle to remote repo"""
     if 'changesets' in pushop.stepsdone:
         return
     pushop.stepsdone.add('changesets')
     if not _pushcheckoutgoing(pushop):
         return
     pushop.repo.prepushoutgoinghooks(pushop.repo,
                                      pushop.remote,
                                      pushop.outgoing)
     outgoing = pushop.outgoing
     unbundle = pushop.remote.capable('unbundle')
     # TODO: get bundlecaps from remote
     bundlecaps = None
     # create a changegroup from local
     if pushop.revs is None and not (outgoing.excluded
                             or pushop.repo.changelog.filteredrevs):
         # push everything,
         # use the fast path, no race possible on push
         bundler = changegroup.cg1packer(pushop.repo, bundlecaps)
         cg = changegroup.getsubset(pushop.repo,
                                    outgoing,
                                    bundler,
                                    'push',
                                    fastpath=True)
     else:
         cg = changegroup.getlocalchangegroup(pushop.repo, 'push', outgoing,
                                         bundlecaps)
 
     # apply changegroup to remote
     if unbundle:
         # local repo finds heads on server, finds out what
         # revs it must push. once revs transferred, if server
         # finds it has different heads (someone else won
         # commit/push race), server aborts.
         if pushop.force:
             remoteheads = ['force']
         else:
             remoteheads = pushop.remoteheads
         # ssh: return remote's addchangegroup()
         # http: return remote's addchangegroup() or 0 for error
         pushop.cgresult = pushop.remote.unbundle(cg, remoteheads,
                                             pushop.repo.url())
     else:
         # we return an integer indicating remote head count
         # change
         pushop.cgresult = pushop.remote.addchangegroup(cg, 'push',
                                                        pushop.repo.url())
 
 def _pushsyncphase(pushop):
     """synchronise phase information locally and remotely"""
     cheads = pushop.commonheads
     # even when we don't push, exchanging phase data is useful
     remotephases = pushop.remote.listkeys('phases')
     if (pushop.ui.configbool('ui', '_usedassubrepo', False)
         and remotephases    # server supports phases
         and pushop.cgresult is None # nothing was pushed
         and remotephases.get('publishing', False)):
         # When:
         # - this is a subrepo push
         # - and remote support phase
         # - and no changeset was pushed
         # - and remote is publishing
         # We may be in issue 3871 case!
         # We drop the possible phase synchronisation done by
         # courtesy to publish changesets possibly locally draft
         # on the remote.
         remotephases = {'publishing': 'True'}
     if not remotephases: # old server or public only reply from non-publishing
         _localphasemove(pushop, cheads)
         # don't push any phase data as there is nothing to push
     else:
         ana = phases.analyzeremotephases(pushop.repo, cheads,
                                          remotephases)
         pheads, droots = ana
         ### Apply remote phase on local
         if remotephases.get('publishing', False):
             _localphasemove(pushop, cheads)
         else: # publish = False
             _localphasemove(pushop, pheads)
             _localphasemove(pushop, cheads, phases.draft)
         ### Apply local phase on remote
 
         if pushop.cgresult:
             if 'phases' in pushop.stepsdone:
                 # phases already pushed though bundle2
                 return
             outdated = pushop.outdatedphases
         else:
             outdated = pushop.fallbackoutdatedphases
 
         pushop.stepsdone.add('phases')
 
         # filter heads already turned public by the push
         outdated = [c for c in outdated if c.node() not in pheads]
         # fallback to independent pushkey command
         for newremotehead in outdated:
             r = pushop.remote.pushkey('phases',
                                       newremotehead.hex(),
                                       str(phases.draft),
                                       str(phases.public))
             if not r:
                 pushop.ui.warn(_('updating %s to public failed!\n')
                                % newremotehead)
 
 def _localphasemove(pushop, nodes, phase=phases.public):
     """move <nodes> to <phase> in the local source repo"""
     if pushop.trmanager:
         phases.advanceboundary(pushop.repo,
                                pushop.trmanager.transaction(),
                                phase,
                                nodes)
     else:
         # repo is not locked, do not change any phases!
         # Informs the user that phases should have been moved when
         # applicable.
         actualmoves = [n for n in nodes if phase < pushop.repo[n].phase()]
         phasestr = phases.phasenames[phase]
         if actualmoves:
             pushop.ui.status(_('cannot lock source repo, skipping '
                                'local %s phase update\n') % phasestr)
 
 def _pushobsolete(pushop):
     """utility function to push obsolete markers to a remote"""
     if 'obsmarkers' in pushop.stepsdone:
         return
     repo = pushop.repo
     remote = pushop.remote
     pushop.stepsdone.add('obsmarkers')
     if pushop.outobsmarkers:
         pushop.ui.debug('try to push obsolete markers to remote\n')
         rslts = []
         remotedata = obsolete._pushkeyescape(sorted(pushop.outobsmarkers))
         for key in sorted(remotedata, reverse=True):
             # reverse sort to ensure we end with dump0
             data = remotedata[key]
             rslts.append(remote.pushkey('obsolete', key, '', data))
         if [r for r in rslts if not r]:
             msg = _('failed to push some obsolete markers!\n')
             repo.ui.warn(msg)
 
 def _pushbookmark(pushop):
     """Update bookmark position on remote"""
     if pushop.cgresult == 0 or 'bookmarks' in pushop.stepsdone:
         return
     pushop.stepsdone.add('bookmarks')
     ui = pushop.ui
     remote = pushop.remote
 
     for b, old, new in pushop.outbookmarks:
         action = 'update'
         if not old:
             action = 'export'
         elif not new:
             action = 'delete'
         if remote.pushkey('bookmarks', b, old, new):
             ui.status(bookmsgmap[action][0] % b)
         else:
             ui.warn(bookmsgmap[action][1] % b)
             # discovery can have set the value form invalid entry
             if pushop.bkresult is not None:
                 pushop.bkresult = 1
 
 class pulloperation(object):
     """A object that represent a single pull operation
 
     It purpose is to carry pull related state and very common operation.
 
     A new should be created at the beginning of each pull and discarded
     afterward.
     """
 
     def __init__(self, repo, remote, heads=None, force=False, bookmarks=(),
                  remotebookmarks=None, streamclonerequested=None):
         # repo we pull into
         self.repo = repo
         # repo we pull from
         self.remote = remote
         # revision we try to pull (None is "all")
         self.heads = heads
         # bookmark pulled explicitly
         self.explicitbookmarks = bookmarks
         # do we force pull?
         self.force = force
         # whether a streaming clone was requested
         self.streamclonerequested = streamclonerequested
         # transaction manager
         self.trmanager = None
         # set of common changeset between local and remote before pull
         self.common = None
         # set of pulled head
         self.rheads = None
         # list of missing changeset to fetch remotely
         self.fetch = None
         # remote bookmarks data
         self.remotebookmarks = remotebookmarks
         # result of changegroup pulling (used as return code by pull)
         self.cgresult = None
         # list of step already done
         self.stepsdone = set()
 
     @util.propertycache
     def pulledsubset(self):
         """heads of the set of changeset target by the pull"""
         # compute target subset
         if self.heads is None:
             # We pulled every thing possible
             # sync on everything common
             c = set(self.common)
             ret = list(self.common)
             for n in self.rheads:
                 if n not in c:
                     ret.append(n)
             return ret
         else:
             # We pulled a specific subset
             # sync on this subset
             return self.heads
 
     @util.propertycache
     def canusebundle2(self):
         return _canusebundle2(self)
 
     @util.propertycache
     def remotebundle2caps(self):
         return bundle2.bundle2caps(self.remote)
 
     def gettransaction(self):
         # deprecated; talk to trmanager directly
         return self.trmanager.transaction()
 
 class transactionmanager(object):
     """An object to manage the life cycle of a transaction
 
     It creates the transaction on demand and calls the appropriate hooks when
     closing the transaction."""
     def __init__(self, repo, source, url):
         self.repo = repo
         self.source = source
         self.url = url
         self._tr = None
 
     def transaction(self):
         """Return an open transaction object, constructing if necessary"""
         if not self._tr:
             trname = '%s\n%s' % (self.source, util.hidepassword(self.url))
             self._tr = self.repo.transaction(trname)
             self._tr.hookargs['source'] = self.source
             self._tr.hookargs['url'] = self.url
         return self._tr
 
     def close(self):
         """close transaction if created"""
         if self._tr is not None:
             self._tr.close()
 
     def release(self):
         """release transaction if created"""
         if self._tr is not None:
             self._tr.release()
 
 def pull(repo, remote, heads=None, force=False, bookmarks=(), opargs=None,
          streamclonerequested=None):
     """Fetch repository data from a remote.
 
     This is the main function used to retrieve data from a remote repository.
 
     ``repo`` is the local repository to clone into.
     ``remote`` is a peer instance.
     ``heads`` is an iterable of revisions we want to pull. ``None`` (the
     default) means to pull everything from the remote.
     ``bookmarks`` is an iterable of bookmarks requesting to be pulled. By
     default, all remote bookmarks are pulled.
     ``opargs`` are additional keyword arguments to pass to ``pulloperation``
     initialization.
     ``streamclonerequested`` is a boolean indicating whether a "streaming
     clone" is requested. A "streaming clone" is essentially a raw file copy
     of revlogs from the server. This only works when the local repository is
     empty. The default value of ``None`` means to respect the server
     configuration for preferring stream clones.
 
     Returns the ``pulloperation`` created for this pull.
     """
     if opargs is None:
         opargs = {}
     pullop = pulloperation(repo, remote, heads, force, bookmarks=bookmarks,
                            streamclonerequested=streamclonerequested, **opargs)
     if pullop.remote.local():
         missing = set(pullop.remote.requirements) - pullop.repo.supported
         if missing:
             msg = _("required features are not"
                     " supported in the destination:"
                     " %s") % (', '.join(sorted(missing)))
             raise error.Abort(msg)
 
     lock = pullop.repo.lock()
     try:
         pullop.trmanager = transactionmanager(repo, 'pull', remote.url())
         streamclone.maybeperformlegacystreamclone(pullop)
+        # This should ideally be in _pullbundle2(). However, it needs to run
+        # before discovery to avoid extra work.
+        _maybeapplyclonebundle(pullop)
         _pulldiscovery(pullop)
         if pullop.canusebundle2:
             _pullbundle2(pullop)
         _pullchangeset(pullop)
         _pullphase(pullop)
         _pullbookmarks(pullop)
         _pullobsolete(pullop)
         pullop.trmanager.close()
     finally:
         pullop.trmanager.release()
         lock.release()
 
     return pullop
 
 # list of steps to perform discovery before pull
 pulldiscoveryorder = []
 
 # Mapping between step name and function
 #
 # This exists to help extensions wrap steps if necessary
 pulldiscoverymapping = {}
 
 def pulldiscovery(stepname):
     """decorator for function performing discovery before pull
 
     The function is added to the step -> function mapping and appended to the
     list of steps.  Beware that decorated function will be added in order (this
     may matter).
 
     You can only use this decorator for a new step, if you want to wrap a step
     from an extension, change the pulldiscovery dictionary directly."""
     def dec(func):
         assert stepname not in pulldiscoverymapping
         pulldiscoverymapping[stepname] = func
         pulldiscoveryorder.append(stepname)
         return func
     return dec
 
 def _pulldiscovery(pullop):
     """Run all discovery steps"""
     for stepname in pulldiscoveryorder:
         step = pulldiscoverymapping[stepname]
         step(pullop)
 
 @pulldiscovery('b1:bookmarks')
 def _pullbookmarkbundle1(pullop):
     """fetch bookmark data in bundle1 case
 
     If not using bundle2, we have to fetch bookmarks before changeset
     discovery to reduce the chance and impact of race conditions."""
     if pullop.remotebookmarks is not None:
         return
     if pullop.canusebundle2 and 'listkeys' in pullop.remotebundle2caps:
         # all known bundle2 servers now support listkeys, but lets be nice with
         # new implementation.
         return
     pullop.remotebookmarks = pullop.remote.listkeys('bookmarks')
 
 
 @pulldiscovery('changegroup')
 def _pulldiscoverychangegroup(pullop):
     """discovery phase for the pull
 
     Current handle changeset discovery only, will change handle all discovery
     at some point."""
     tmp = discovery.findcommonincoming(pullop.repo,
                                        pullop.remote,
                                        heads=pullop.heads,
                                        force=pullop.force)
     common, fetch, rheads = tmp
     nm = pullop.repo.unfiltered().changelog.nodemap
     if fetch and rheads:
         # If a remote heads in filtered locally, lets drop it from the unknown
         # remote heads and put in back in common.
         #
         # This is a hackish solution to catch most of "common but locally
         # hidden situation".  We do not performs discovery on unfiltered
         # repository because it end up doing a pathological amount of round
         # trip for w huge amount of changeset we do not care about.
         #
         # If a set of such "common but filtered" changeset exist on the server
         # but are not including a remote heads, we'll not be able to detect it,
         scommon = set(common)
         filteredrheads = []
         for n in rheads:
             if n in nm:
                 if n not in scommon:
                     common.append(n)
             else:
                 filteredrheads.append(n)
         if not filteredrheads:
             fetch = []
         rheads = filteredrheads
     pullop.common = common
     pullop.fetch = fetch
     pullop.rheads = rheads
 
 def _pullbundle2(pullop):
     """pull data using bundle2
 
     For now, the only supported data are changegroup."""
     kwargs = {'bundlecaps': caps20to10(pullop.repo)}
 
     streaming, streamreqs = streamclone.canperformstreamclone(pullop)
 
     # pulling changegroup
     pullop.stepsdone.add('changegroup')
 
     kwargs['common'] = pullop.common
     kwargs['heads'] = pullop.heads or pullop.rheads
     kwargs['cg'] = pullop.fetch
     if 'listkeys' in pullop.remotebundle2caps:
         kwargs['listkeys'] = ['phase']
         if pullop.remotebookmarks is None:
             # make sure to always includes bookmark data when migrating
             # `hg incoming --bundle` to using this function.
             kwargs['listkeys'].append('bookmarks')
     if streaming:
         pullop.repo.ui.status(_('streaming all changes\n'))
     elif not pullop.fetch:
         pullop.repo.ui.status(_("no changes found\n"))
         pullop.cgresult = 0
     else:
         if pullop.heads is None and list(pullop.common) == [nullid]:
             pullop.repo.ui.status(_("requesting all changes\n"))
     if obsolete.isenabled(pullop.repo, obsolete.exchangeopt):
         remoteversions = bundle2.obsmarkersversion(pullop.remotebundle2caps)
         if obsolete.commonversion(remoteversions) is not None:
             kwargs['obsmarkers'] = True
             pullop.stepsdone.add('obsmarkers')
     _pullbundle2extraprepare(pullop, kwargs)
     bundle = pullop.remote.getbundle('pull', **kwargs)
     try:
         op = bundle2.processbundle(pullop.repo, bundle, pullop.gettransaction)
     except error.BundleValueError as exc:
         raise error.Abort('missing support for %s' % exc)
 
     if pullop.fetch:
         results = [cg['return'] for cg in op.records['changegroup']]
         pullop.cgresult = changegroup.combineresults(results)
 
     # processing phases change
     for namespace, value in op.records['listkeys']:
         if namespace == 'phases':
             _pullapplyphases(pullop, value)
 
     # processing bookmark update
     for namespace, value in op.records['listkeys']:
         if namespace == 'bookmarks':
             pullop.remotebookmarks = value
 
     # bookmark data were either already there or pulled in the bundle
     if pullop.remotebookmarks is not None:
         _pullbookmarks(pullop)
 
 def _pullbundle2extraprepare(pullop, kwargs):
     """hook function so that extensions can extend the getbundle call"""
     pass
 
 def _pullchangeset(pullop):
     """pull changeset from unbundle into the local repo"""
     # We delay the open of the transaction as late as possible so we
     # don't open transaction for nothing or you break future useful
     # rollback call
     if 'changegroup' in pullop.stepsdone:
         return
     pullop.stepsdone.add('changegroup')
     if not pullop.fetch:
         pullop.repo.ui.status(_("no changes found\n"))
         pullop.cgresult = 0
         return
     pullop.gettransaction()
     if pullop.heads is None and list(pullop.common) == [nullid]:
         pullop.repo.ui.status(_("requesting all changes\n"))
     elif pullop.heads is None and pullop.remote.capable('changegroupsubset'):
         # issue1320, avoid a race if remote changed after discovery
         pullop.heads = pullop.rheads
 
     if pullop.remote.capable('getbundle'):
         # TODO: get bundlecaps from remote
         cg = pullop.remote.getbundle('pull', common=pullop.common,
                                      heads=pullop.heads or pullop.rheads)
     elif pullop.heads is None:
         cg = pullop.remote.changegroup(pullop.fetch, 'pull')
     elif not pullop.remote.capable('changegroupsubset'):
         raise error.Abort(_("partial pull cannot be done because "
                            "other repository doesn't support "
                            "changegroupsubset."))
     else:
         cg = pullop.remote.changegroupsubset(pullop.fetch, pullop.heads, 'pull')
     pullop.cgresult = changegroup.addchangegroup(pullop.repo, cg, 'pull',
                                                  pullop.remote.url())
 
 def _pullphase(pullop):
     # Get remote phases data from remote
     if 'phases' in pullop.stepsdone:
         return
     remotephases = pullop.remote.listkeys('phases')
     _pullapplyphases(pullop, remotephases)
 
 def _pullapplyphases(pullop, remotephases):
     """apply phase movement from observed remote state"""
     if 'phases' in pullop.stepsdone:
         return
     pullop.stepsdone.add('phases')
     publishing = bool(remotephases.get('publishing', False))
     if remotephases and not publishing:
         # remote is new and unpublishing
         pheads, _dr = phases.analyzeremotephases(pullop.repo,
                                                  pullop.pulledsubset,
                                                  remotephases)
         dheads = pullop.pulledsubset
     else:
         # Remote is old or publishing all common changesets
         # should be seen as public
         pheads = pullop.pulledsubset
         dheads = []
     unfi = pullop.repo.unfiltered()
     phase = unfi._phasecache.phase
     rev = unfi.changelog.nodemap.get
     public = phases.public
     draft = phases.draft
 
     # exclude changesets already public locally and update the others
     pheads = [pn for pn in pheads if phase(unfi, rev(pn)) > public]
     if pheads:
         tr = pullop.gettransaction()
         phases.advanceboundary(pullop.repo, tr, public, pheads)
 
     # exclude changesets already draft locally and update the others
     dheads = [pn for pn in dheads if phase(unfi, rev(pn)) > draft]
     if dheads:
         tr = pullop.gettransaction()
         phases.advanceboundary(pullop.repo, tr, draft, dheads)
 
 def _pullbookmarks(pullop):
     """process the remote bookmark information to update the local one"""
     if 'bookmarks' in pullop.stepsdone:
         return
     pullop.stepsdone.add('bookmarks')
     repo = pullop.repo
     remotebookmarks = pullop.remotebookmarks
     bookmod.updatefromremote(repo.ui, repo, remotebookmarks,
                              pullop.remote.url(),
                              pullop.gettransaction,
                              explicit=pullop.explicitbookmarks)
 
 def _pullobsolete(pullop):
     """utility function to pull obsolete markers from a remote
 
     The `gettransaction` is function that return the pull transaction, creating
     one if necessary. We return the transaction to inform the calling code that
     a new transaction have been created (when applicable).
 
     Exists mostly to allow overriding for experimentation purpose"""
     if 'obsmarkers' in pullop.stepsdone:
         return
     pullop.stepsdone.add('obsmarkers')
     tr = None
     if obsolete.isenabled(pullop.repo, obsolete.exchangeopt):
         pullop.repo.ui.debug('fetching remote obsolete markers\n')
         remoteobs = pullop.remote.listkeys('obsolete')
         if 'dump0' in remoteobs:
             tr = pullop.gettransaction()
             for key in sorted(remoteobs, reverse=True):
                 if key.startswith('dump'):
                     data = base85.b85decode(remoteobs[key])
                     pullop.repo.obsstore.mergemarkers(tr, data)
             pullop.repo.invalidatevolatilesets()
     return tr
 
 def caps20to10(repo):
     """return a set with appropriate options to use bundle20 during getbundle"""
     caps = set(['HG20'])
     capsblob = bundle2.encodecaps(bundle2.getrepocaps(repo))
     caps.add('bundle2=' + urllib.quote(capsblob))
     return caps
 
 # List of names of steps to perform for a bundle2 for getbundle, order matters.
 getbundle2partsorder = []
 
 # Mapping between step name and function
 #
 # This exists to help extensions wrap steps if necessary
 getbundle2partsmapping = {}
 
 def getbundle2partsgenerator(stepname, idx=None):
     """decorator for function generating bundle2 part for getbundle
 
     The function is added to the step -> function mapping and appended to the
     list of steps.  Beware that decorated functions will be added in order
     (this may matter).
 
     You can only use this decorator for new steps, if you want to wrap a step
     from an extension, attack the getbundle2partsmapping dictionary directly."""
     def dec(func):
         assert stepname not in getbundle2partsmapping
         getbundle2partsmapping[stepname] = func
         if idx is None:
             getbundle2partsorder.append(stepname)
         else:
             getbundle2partsorder.insert(idx, stepname)
         return func
     return dec
 
 def getbundle(repo, source, heads=None, common=None, bundlecaps=None,
               **kwargs):
     """return a full bundle (with potentially multiple kind of parts)
 
     Could be a bundle HG10 or a bundle HG20 depending on bundlecaps
     passed. For now, the bundle can contain only changegroup, but this will
     changes when more part type will be available for bundle2.
 
     This is different from changegroup.getchangegroup that only returns an HG10
     changegroup bundle. They may eventually get reunited in the future when we
     have a clearer idea of the API we what to query different data.
 
     The implementation is at a very early stage and will get massive rework
     when the API of bundle is refined.
     """
     # bundle10 case
     usebundle2 = False
     if bundlecaps is not None:
         usebundle2 = any((cap.startswith('HG2') for cap in bundlecaps))
     if not usebundle2:
         if bundlecaps and not kwargs.get('cg', True):
             raise ValueError(_('request for bundle10 must include changegroup'))
 
         if kwargs:
             raise ValueError(_('unsupported getbundle arguments: %s')
                              % ', '.join(sorted(kwargs.keys())))
         return changegroup.getchangegroup(repo, source, heads=heads,
                                           common=common, bundlecaps=bundlecaps)
 
     # bundle20 case
     b2caps = {}
     for bcaps in bundlecaps:
         if bcaps.startswith('bundle2='):
             blob = urllib.unquote(bcaps[len('bundle2='):])
             b2caps.update(bundle2.decodecaps(blob))
     bundler = bundle2.bundle20(repo.ui, b2caps)
 
     kwargs['heads'] = heads
     kwargs['common'] = common
 
     for name in getbundle2partsorder:
         func = getbundle2partsmapping[name]
         func(bundler, repo, source, bundlecaps=bundlecaps, b2caps=b2caps,
              **kwargs)
 
     return util.chunkbuffer(bundler.getchunks())
 
 @getbundle2partsgenerator('changegroup')
 def _getbundlechangegrouppart(bundler, repo, source, bundlecaps=None,
                               b2caps=None, heads=None, common=None, **kwargs):
     """add a changegroup part to the requested bundle"""
     cg = None
     if kwargs.get('cg', True):
         # build changegroup bundle here.
         version = None
         cgversions = b2caps.get('changegroup')
         getcgkwargs = {}
         if cgversions:  # 3.1 and 3.2 ship with an empty value
             cgversions = [v for v in cgversions if v in changegroup.packermap]
             if not cgversions:
                 raise ValueError(_('no common changegroup version'))
             version = getcgkwargs['version'] = max(cgversions)
         outgoing = changegroup.computeoutgoing(repo, heads, common)
         cg = changegroup.getlocalchangegroupraw(repo, source, outgoing,
                                                 bundlecaps=bundlecaps,
                                                 **getcgkwargs)
 
     if cg:
         part = bundler.newpart('changegroup', data=cg)
         if version is not None:
             part.addparam('version', version)
         part.addparam('nbchanges', str(len(outgoing.missing)), mandatory=False)
 
 @getbundle2partsgenerator('listkeys')
 def _getbundlelistkeysparts(bundler, repo, source, bundlecaps=None,
                             b2caps=None, **kwargs):
     """add parts containing listkeys namespaces to the requested bundle"""
     listkeys = kwargs.get('listkeys', ())
     for namespace in listkeys:
         part = bundler.newpart('listkeys')
         part.addparam('namespace', namespace)
         keys = repo.listkeys(namespace).items()
         part.data = pushkey.encodekeys(keys)
 
 @getbundle2partsgenerator('obsmarkers')
 def _getbundleobsmarkerpart(bundler, repo, source, bundlecaps=None,
                             b2caps=None, heads=None, **kwargs):
     """add an obsolescence markers part to the requested bundle"""
     if kwargs.get('obsmarkers', False):
         if heads is None:
             heads = repo.heads()
         subset = [c.node() for c in repo.set('::%ln', heads)]
         markers = repo.obsstore.relevantmarkers(subset)
         markers = sorted(markers)
         buildobsmarkerspart(bundler, markers)
 
 @getbundle2partsgenerator('hgtagsfnodes')
 def _getbundletagsfnodes(bundler, repo, source, bundlecaps=None,
                          b2caps=None, heads=None, common=None,
                          **kwargs):
     """Transfer the .hgtags filenodes mapping.
 
     Only values for heads in this bundle will be transferred.
 
     The part data consists of pairs of 20 byte changeset node and .hgtags
     filenodes raw values.
     """
     # Don't send unless:
     # - changeset are being exchanged,
     # - the client supports it.
     if not (kwargs.get('cg', True) and 'hgtagsfnodes' in b2caps):
         return
 
     outgoing = changegroup.computeoutgoing(repo, heads, common)
 
     if not outgoing.missingheads:
         return
 
     cache = tags.hgtagsfnodescache(repo.unfiltered())
     chunks = []
 
     # .hgtags fnodes are only relevant for head changesets. While we could
     # transfer values for all known nodes, there will likely be little to
     # no benefit.
     #
     # We don't bother using a generator to produce output data because
     # a) we only have 40 bytes per head and even esoteric numbers of heads
     # consume little memory (1M heads is 40MB) b) we don't want to send the
     # part if we don't have entries and knowing if we have entries requires
     # cache lookups.
     for node in outgoing.missingheads:
         # Don't compute missing, as this may slow down serving.
         fnode = cache.getfnode(node, computemissing=False)
         if fnode is not None:
             chunks.extend([node, fnode])
 
     if chunks:
         bundler.newpart('hgtagsfnodes', data=''.join(chunks))
 
 def check_heads(repo, their_heads, context):
     """check if the heads of a repo have been modified
 
     Used by peer for unbundling.
     """
     heads = repo.heads()
     heads_hash = util.sha1(''.join(sorted(heads))).digest()
     if not (their_heads == ['force'] or their_heads == heads or
             their_heads == ['hashed', heads_hash]):
         # someone else committed/pushed/unbundled while we
         # were transferring data
         raise error.PushRaced('repository changed while %s - '
                               'please try again' % context)
 
 def unbundle(repo, cg, heads, source, url):
     """Apply a bundle to a repo.
 
     this function makes sure the repo is locked during the application and have
     mechanism to check that no push race occurred between the creation of the
     bundle and its application.
 
     If the push was raced as PushRaced exception is raised."""
     r = 0
     # need a transaction when processing a bundle2 stream
     # [wlock, lock, tr] - needs to be an array so nested functions can modify it
     lockandtr = [None, None, None]
     recordout = None
     # quick fix for output mismatch with bundle2 in 3.4
     captureoutput = repo.ui.configbool('experimental', 'bundle2-output-capture',
                                        False)
     if url.startswith('remote:http:') or url.startswith('remote:https:'):
         captureoutput = True
     try:
         check_heads(repo, heads, 'uploading changes')
         # push can proceed
         if util.safehasattr(cg, 'params'):
             r = None
             try:
                 def gettransaction():
                     if not lockandtr[2]:
                         lockandtr[0] = repo.wlock()
                         lockandtr[1] = repo.lock()
                         lockandtr[2] = repo.transaction(source)
                         lockandtr[2].hookargs['source'] = source
                         lockandtr[2].hookargs['url'] = url
                         lockandtr[2].hookargs['bundle2'] = '1'
                     return lockandtr[2]
 
                 # Do greedy locking by default until we're satisfied with lazy
                 # locking.
                 if not repo.ui.configbool('experimental', 'bundle2lazylocking'):
                     gettransaction()
 
                 op = bundle2.bundleoperation(repo, gettransaction,
                                              captureoutput=captureoutput)
                 try:
                     op = bundle2.processbundle(repo, cg, op=op)
                 finally:
                     r = op.reply
                     if captureoutput and r is not None:
                         repo.ui.pushbuffer(error=True, subproc=True)
                         def recordout(output):
                             r.newpart('output', data=output, mandatory=False)
                 if lockandtr[2] is not None:
                     lockandtr[2].close()
             except BaseException as exc:
                 exc.duringunbundle2 = True
                 if captureoutput and r is not None:
                     parts = exc._bundle2salvagedoutput = r.salvageoutput()
                     def recordout(output):
                         part = bundle2.bundlepart('output', data=output,
                                                   mandatory=False)
                         parts.append(part)
                 raise
         else:
             lockandtr[1] = repo.lock()
             r = changegroup.addchangegroup(repo, cg, source, url)
     finally:
         lockmod.release(lockandtr[2], lockandtr[1], lockandtr[0])
         if recordout is not None:
             recordout(repo.ui.popbuffer())
     return r
+
+def _maybeapplyclonebundle(pullop):
+    """Apply a clone bundle from a remote, if possible."""
+
+    repo = pullop.repo
+    remote = pullop.remote
+
+    if not repo.ui.configbool('experimental', 'clonebundles', False):
+        return
+
+    if pullop.heads:
+        return
+
+    if not remote.capable('clonebundles'):
+        return
+
+    res = remote._call('clonebundles')
+    entries = parseclonebundlesmanifest(res)
+
+    # TODO filter entries by supported features.
+    # TODO sort entries by user preferences.
+
+    if not entries:
+        repo.ui.note(_('no clone bundles available on remote; '
+                       'falling back to regular clone\n'))
+        return
+
+    url = entries[0]['URL']
+    repo.ui.status(_('applying clone bundle from %s\n') % url)
+    if trypullbundlefromurl(repo.ui, repo, url):
+        repo.ui.status(_('finished applying clone bundle\n'))
+    # Bundle failed.
+    #
+    # We abort by default to avoid the thundering herd of
+    # clients flooding a server that was expecting expensive
+    # clone load to be offloaded.
+    elif repo.ui.configbool('ui', 'clonebundlefallback', False):
+        repo.ui.warn(_('falling back to normal clone\n'))
+    else:
+        raise error.Abort(_('error applying bundle'),
+                          hint=_('consider contacting the server '
+                                 'operator if this error persists'))
+
+def parseclonebundlesmanifest(s):
+    """Parses the raw text of a clone bundles manifest.
+
+    Returns a list of dicts. The dicts have a ``URL`` key corresponding
+    to the URL and other keys are the attributes for the entry.
+    """
+    m = []
+    for line in s.splitlines():
+        fields = line.split()
+        if not fields:
+            continue
+        attrs = {'URL': fields[0]}
+        for rawattr in fields[1:]:
+            key, value = rawattr.split('=', 1)
+            attrs[urllib.unquote(key)] = urllib.unquote(value)
+
+        m.append(attrs)
+
+    return m
+
+def trypullbundlefromurl(ui, repo, url):
+    """Attempt to apply a bundle from a URL."""
+    lock = repo.lock()
+    try:
+        tr = repo.transaction('bundleurl')
+        try:
+            try:
+                fh = urlmod.open(ui, url)
+                cg = readbundle(ui, fh, 'stream')
+                changegroup.addchangegroup(repo, cg, 'clonebundles', url)
+                tr.close()
+                return True
+            except urllib2.HTTPError as e:
+                ui.warn(_('HTTP error fetching bundle: %s\n') % str(e))
+            except urllib2.URLError as e:
+                ui.warn(_('error fetching bundle: %s\n') % e.reason)
+
+            return False
+        finally:
+            tr.release()
+    finally:
+        lock.release()

mercurial/help/config.txt

@@ -1,1850 +1,1865
 The Mercurial system uses a set of configuration files to control
 aspects of its behavior.
 
 Troubleshooting
 ===============
 
 If you're having problems with your configuration,
 :hg:`config --debug` can help you understand what is introducing
 a setting into your environment.
 
 See :hg:`help config.syntax` and :hg:`help config.files`
 for information about how and where to override things.
 
 Format
 ======
 
 The configuration files use a simple ini-file format. A configuration
 file consists of sections, led by a ``[section]`` header and followed
 by ``name = value`` entries::
 
   [ui]
   username = Firstname Lastname <[e-mail]>
   verbose = True
 
 The above entries will be referred to as ``ui.username`` and
 ``ui.verbose``, respectively. See :hg:`help config.syntax`.
 
 Files
 =====
 
 Mercurial reads configuration data from several files, if they exist.
 These files do not exist by default and you will have to create the
 appropriate configuration files yourself: global configuration like
 the username setting is typically put into
 ``%USERPROFILE%\mercurial.ini`` or ``$HOME/.hgrc`` and local
 configuration is put into the per-repository ``<repo>/.hg/hgrc`` file.
 
 The names of these files depend on the system on which Mercurial is
 installed. ``*.rc`` files from a single directory are read in
 alphabetical order, later ones overriding earlier ones. Where multiple
 paths are given below, settings from earlier paths override later
 ones.
 
 .. container:: verbose.unix
 
   On Unix, the following files are consulted:
 
   - ``<repo>/.hg/hgrc`` (per-repository)
   - ``$HOME/.hgrc`` (per-user)
   - ``<install-root>/etc/mercurial/hgrc`` (per-installation)
   - ``<install-root>/etc/mercurial/hgrc.d/*.rc`` (per-installation)
   - ``/etc/mercurial/hgrc`` (per-system)
   - ``/etc/mercurial/hgrc.d/*.rc`` (per-system)
   - ``<internal>/default.d/*.rc`` (defaults)
 
 .. container:: verbose.windows
 
   On Windows, the following files are consulted:
 
   - ``<repo>/.hg/hgrc`` (per-repository)
   - ``%USERPROFILE%\.hgrc`` (per-user)
   - ``%USERPROFILE%\Mercurial.ini`` (per-user)
   - ``%HOME%\.hgrc`` (per-user)
   - ``%HOME%\Mercurial.ini`` (per-user)
   - ``<install-dir>\Mercurial.ini`` (per-installation)
   - ``<install-dir>\hgrc.d\*.rc`` (per-installation)
   - ``HKEY_LOCAL_MACHINE\SOFTWARE\Mercurial`` (per-installation)
   - ``<internal>/default.d/*.rc`` (defaults)
 
   .. note::
 
    The registry key ``HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Mercurial``
    is used when running 32-bit Python on 64-bit Windows.
 
 .. container:: verbose.plan9
 
   On Plan9, the following files are consulted:
 
   - ``<repo>/.hg/hgrc`` (per-repository)
   - ``$home/lib/hgrc`` (per-user)
   - ``<install-root>/lib/mercurial/hgrc`` (per-installation)
   - ``<install-root>/lib/mercurial/hgrc.d/*.rc`` (per-installation)
   - ``/lib/mercurial/hgrc`` (per-system)
   - ``/lib/mercurial/hgrc.d/*.rc`` (per-system)
   - ``<internal>/default.d/*.rc`` (defaults)
 
 Per-repository configuration options only apply in a
 particular repository. This file is not version-controlled, and
 will not get transferred during a "clone" operation. Options in
 this file override options in all other configuration files. On
 Plan 9 and Unix, most of this file will be ignored if it doesn't
 belong to a trusted user or to a trusted group. See
 :hg:`help config.trusted` for more details.
 
 Per-user configuration file(s) are for the user running Mercurial. On
 Windows 9x, ``%HOME%`` is replaced by ``%APPDATA%``. Options in these
 files apply to all Mercurial commands executed by this user in any
 directory. Options in these files override per-system and per-installation
 options.
 
 Per-installation configuration files are searched for in the
 directory where Mercurial is installed. ``<install-root>`` is the
 parent directory of the **hg** executable (or symlink) being run. For
 example, if installed in ``/shared/tools/bin/hg``, Mercurial will look
 in ``/shared/tools/etc/mercurial/hgrc``. Options in these files apply
 to all Mercurial commands executed by any user in any directory.
 
 Per-installation configuration files are for the system on
 which Mercurial is running. Options in these files apply to all
 Mercurial commands executed by any user in any directory. Registry
 keys contain PATH-like strings, every part of which must reference
 a ``Mercurial.ini`` file or be a directory where ``*.rc`` files will
 be read.  Mercurial checks each of these locations in the specified
 order until one or more configuration files are detected.
 
 Per-system configuration files are for the system on which Mercurial
 is running. Options in these files apply to all Mercurial commands
 executed by any user in any directory. Options in these files
 override per-installation options.
 
 Mercurial comes with some default configuration. The default configuration
 files are installed with Mercurial and will be overwritten on upgrades. Default
 configuration files should never be edited by users or administrators but can
 be overridden in other configuration files. So far the directory only contains
 merge tool configuration but packagers can also put other default configuration
 there.
 
 Syntax
 ======
 
 A configuration file consists of sections, led by a ``[section]`` header
 and followed by ``name = value`` entries (sometimes called
 ``configuration keys``)::
 
     [spam]
     eggs=ham
     green=
        eggs
 
 Each line contains one entry. If the lines that follow are indented,
 they are treated as continuations of that entry. Leading whitespace is
 removed from values. Empty lines are skipped. Lines beginning with
 ``#`` or ``;`` are ignored and may be used to provide comments.
 
 Configuration keys can be set multiple times, in which case Mercurial
 will use the value that was configured last. As an example::
 
     [spam]
     eggs=large
     ham=serrano
     eggs=small
 
 This would set the configuration key named ``eggs`` to ``small``.
 
 It is also possible to define a section multiple times. A section can
 be redefined on the same and/or on different configuration files. For
 example::
 
     [foo]
     eggs=large
     ham=serrano
     eggs=small
 
     [bar]
     eggs=ham
     green=
        eggs
 
     [foo]
     ham=prosciutto
     eggs=medium
     bread=toasted
 
 This would set the ``eggs``, ``ham``, and ``bread`` configuration keys
 of the ``foo`` section to ``medium``, ``prosciutto``, and ``toasted``,
 respectively. As you can see there only thing that matters is the last
 value that was set for each of the configuration keys.
 
 If a configuration key is set multiple times in different
 configuration files the final value will depend on the order in which
 the different configuration files are read, with settings from earlier
 paths overriding later ones as described on the ``Files`` section
 above.
 
 A line of the form ``%include file`` will include ``file`` into the
 current configuration file. The inclusion is recursive, which means
 that included files can include other files. Filenames are relative to
 the configuration file in which the ``%include`` directive is found.
 Environment variables and ``~user`` constructs are expanded in
 ``file``. This lets you do something like::
 
   %include ~/.hgrc.d/$HOST.rc
 
 to include a different configuration file on each computer you use.
 
 A line with ``%unset name`` will remove ``name`` from the current
 section, if it has been set previously.
 
 The values are either free-form text strings, lists of text strings,
 or Boolean values. Boolean values can be set to true using any of "1",
 "yes", "true", or "on" and to false using "0", "no", "false", or "off"
 (all case insensitive).
 
 List values are separated by whitespace or comma, except when values are
 placed in double quotation marks::
 
   allow_read = "John Doe, PhD", brian, betty
 
 Quotation marks can be escaped by prefixing them with a backslash. Only
 quotation marks at the beginning of a word is counted as a quotation
 (e.g., ``foo"bar baz`` is the list of ``foo"bar`` and ``baz``).
 
 Sections
 ========
 
 This section describes the different sections that may appear in a
 Mercurial configuration file, the purpose of each section, its possible
 keys, and their possible values.
 
 ``alias``
 ---------
 
 Defines command aliases.
 
 Aliases allow you to define your own commands in terms of other
 commands (or aliases), optionally including arguments. Positional
 arguments in the form of ``$1``, ``$2``, etc. in the alias definition
 are expanded by Mercurial before execution. Positional arguments not
 already used by ``$N`` in the definition are put at the end of the
 command to be executed.
 
 Alias definitions consist of lines of the form::
 
     <alias> = <command> [<argument>]...
 
 For example, this definition::
 
     latest = log --limit 5
 
 creates a new command ``latest`` that shows only the five most recent
 changesets. You can define subsequent aliases using earlier ones::
 
     stable5 = latest -b stable
 
 .. note::
 
    It is possible to create aliases with the same names as
    existing commands, which will then override the original
    definitions. This is almost always a bad idea!
 
 An alias can start with an exclamation point (``!``) to make it a
 shell alias. A shell alias is executed with the shell and will let you
 run arbitrary commands. As an example, ::
 
    echo = !echo $@
 
 will let you do ``hg echo foo`` to have ``foo`` printed in your
 terminal. A better example might be::
 
    purge = !$HG status --no-status --unknown -0 | xargs -0 rm
 
 which will make ``hg purge`` delete all unknown files in the
 repository in the same manner as the purge extension.
 
 Positional arguments like ``$1``, ``$2``, etc. in the alias definition
 expand to the command arguments. Unmatched arguments are
 removed. ``$0`` expands to the alias name and ``$@`` expands to all
 arguments separated by a space. ``"$@"`` (with quotes) expands to all
 arguments quoted individually and separated by a space. These expansions
 happen before the command is passed to the shell.
 
 Shell aliases are executed in an environment where ``$HG`` expands to
 the path of the Mercurial that was used to execute the alias. This is
 useful when you want to call further Mercurial commands in a shell
 alias, as was done above for the purge alias. In addition,
 ``$HG_ARGS`` expands to the arguments given to Mercurial. In the ``hg
 echo foo`` call above, ``$HG_ARGS`` would expand to ``echo foo``.
 
 .. note::
 
    Some global configuration options such as ``-R`` are
    processed before shell aliases and will thus not be passed to
    aliases.
 
 
 ``annotate``
 ------------
 
 Settings used when displaying file annotations. All values are
 Booleans and default to False. See :hg:`help config.diff` for
 related options for the diff command.
 
 ``ignorews``
     Ignore white space when comparing lines.
 
 ``ignorewsamount``
     Ignore changes in the amount of white space.
 
 ``ignoreblanklines``
     Ignore changes whose lines are all blank.
 
 
 ``auth``
 --------
 
 Authentication credentials for HTTP authentication. This section
 allows you to store usernames and passwords for use when logging
 *into* HTTP servers. See :hg:`help config.web` if
 you want to configure *who* can login to your HTTP server.
 
 Each line has the following format::
 
     <name>.<argument> = <value>
 
 where ``<name>`` is used to group arguments into authentication
 entries. Example::
 
     foo.prefix = hg.intevation.org/mercurial
     foo.username = foo
     foo.password = bar
     foo.schemes = http https
 
     bar.prefix = secure.example.org
     bar.key = path/to/file.key
     bar.cert = path/to/file.cert
     bar.schemes = https
 
 Supported arguments:
 
 ``prefix``
     Either ``*`` or a URI prefix with or without the scheme part.
     The authentication entry with the longest matching prefix is used
     (where ``*`` matches everything and counts as a match of length
     1). If the prefix doesn't include a scheme, the match is performed
     against the URI with its scheme stripped as well, and the schemes
     argument, q.v., is then subsequently consulted.
 
 ``username``
     Optional. Username to authenticate with. If not given, and the
     remote site requires basic or digest authentication, the user will
     be prompted for it. Environment variables are expanded in the
     username letting you do ``foo.username = $USER``. If the URI
     includes a username, only ``[auth]`` entries with a matching
     username or without a username will be considered.
 
 ``password``
     Optional. Password to authenticate with. If not given, and the
     remote site requires basic or digest authentication, the user
     will be prompted for it.
 
 ``key``
     Optional. PEM encoded client certificate key file. Environment
     variables are expanded in the filename.
 
 ``cert``
     Optional. PEM encoded client certificate chain file. Environment
     variables are expanded in the filename.
 
 ``schemes``
     Optional. Space separated list of URI schemes to use this
     authentication entry with. Only used if the prefix doesn't include
     a scheme. Supported schemes are http and https. They will match
     static-http and static-https respectively, as well.
     (default: https)
 
 If no suitable authentication entry is found, the user is prompted
 for credentials as usual if required by the remote.
 
 
 ``committemplate``
 ------------------
 
 ``changeset``
     String: configuration in this section is used as the template to
     customize the text shown in the editor when committing.
 
 In addition to pre-defined template keywords, commit log specific one
 below can be used for customization:
 
 ``extramsg``
     String: Extra message (typically 'Leave message empty to abort
     commit.'). This may be changed by some commands or extensions.
 
 For example, the template configuration below shows as same text as
 one shown by default::
 
     [committemplate]
     changeset = {desc}\n\n
         HG: Enter commit message.  Lines beginning with 'HG:' are removed.
         HG: {extramsg}
         HG: --
         HG: user: {author}\n{ifeq(p2rev, "-1", "",
        "HG: branch merge\n")
        }HG: branch '{branch}'\n{if(activebookmark,
        "HG: bookmark '{activebookmark}'\n")   }{subrepos %
        "HG: subrepo {subrepo}\n"              }{file_adds %
        "HG: added {file}\n"                   }{file_mods %
        "HG: changed {file}\n"                 }{file_dels %
        "HG: removed {file}\n"                 }{if(files, "",
        "HG: no files changed\n")}
 
 .. note::
 
    For some problematic encodings (see :hg:`help win32mbcs` for
    detail), this customization should be configured carefully, to
    avoid showing broken characters.
 
    For example, if a multibyte character ending with backslash (0x5c) is
    followed by the ASCII character 'n' in the customized template,
    the sequence of backslash and 'n' is treated as line-feed unexpectedly
    (and the multibyte character is broken, too).
 
 Customized template is used for commands below (``--edit`` may be
 required):
 
 - :hg:`backout`
 - :hg:`commit`
 - :hg:`fetch` (for merge commit only)
 - :hg:`graft`
 - :hg:`histedit`
 - :hg:`import`
 - :hg:`qfold`, :hg:`qnew` and :hg:`qrefresh`
 - :hg:`rebase`
 - :hg:`shelve`
 - :hg:`sign`
 - :hg:`tag`
 - :hg:`transplant`
 
 Configuring items below instead of ``changeset`` allows showing
 customized message only for specific actions, or showing different
 messages for each action.
 
 - ``changeset.backout`` for :hg:`backout`
 - ``changeset.commit.amend.merge`` for :hg:`commit --amend` on merges
 - ``changeset.commit.amend.normal`` for :hg:`commit --amend` on other
 - ``changeset.commit.normal.merge`` for :hg:`commit` on merges
 - ``changeset.commit.normal.normal`` for :hg:`commit` on other
 - ``changeset.fetch`` for :hg:`fetch` (impling merge commit)
 - ``changeset.gpg.sign`` for :hg:`sign`
 - ``changeset.graft`` for :hg:`graft`
 - ``changeset.histedit.edit`` for ``edit`` of :hg:`histedit`
 - ``changeset.histedit.fold`` for ``fold`` of :hg:`histedit`
 - ``changeset.histedit.mess`` for ``mess`` of :hg:`histedit`
 - ``changeset.histedit.pick`` for ``pick`` of :hg:`histedit`
 - ``changeset.import.bypass`` for :hg:`import --bypass`
 - ``changeset.import.normal.merge`` for :hg:`import` on merges
 - ``changeset.import.normal.normal`` for :hg:`import` on other
 - ``changeset.mq.qnew`` for :hg:`qnew`
 - ``changeset.mq.qfold`` for :hg:`qfold`
 - ``changeset.mq.qrefresh`` for :hg:`qrefresh`
 - ``changeset.rebase.collapse`` for :hg:`rebase --collapse`
 - ``changeset.rebase.merge`` for :hg:`rebase` on merges
 - ``changeset.rebase.normal`` for :hg:`rebase` on other
 - ``changeset.shelve.shelve`` for :hg:`shelve`
 - ``changeset.tag.add`` for :hg:`tag` without ``--remove``
 - ``changeset.tag.remove`` for :hg:`tag --remove`
 - ``changeset.transplant.merge`` for :hg:`transplant` on merges
 - ``changeset.transplant.normal`` for :hg:`transplant` on other
 
 These dot-separated lists of names are treated as hierarchical ones.
 For example, ``changeset.tag.remove`` customizes the commit message
 only for :hg:`tag --remove`, but ``changeset.tag`` customizes the
 commit message for :hg:`tag` regardless of ``--remove`` option.
 
 When the external editor is invoked for a commit, the corresponding
 dot-separated list of names without the ``changeset.`` prefix
 (e.g. ``commit.normal.normal``) is in the ``HGEDITFORM`` environment
 variable.
 
 In this section, items other than ``changeset`` can be referred from
 others. For example, the configuration to list committed files up
 below can be referred as ``{listupfiles}``::
 
     [committemplate]
     listupfiles = {file_adds %
        "HG: added {file}\n"     }{file_mods %
        "HG: changed {file}\n"   }{file_dels %
        "HG: removed {file}\n"   }{if(files, "",
        "HG: no files changed\n")}
 
 ``decode/encode``
 -----------------
 
 Filters for transforming files on checkout/checkin. This would
 typically be used for newline processing or other
 localization/canonicalization of files.
 
 Filters consist of a filter pattern followed by a filter command.
 Filter patterns are globs by default, rooted at the repository root.
 For example, to match any file ending in ``.txt`` in the root
 directory only, use the pattern ``*.txt``. To match any file ending
 in ``.c`` anywhere in the repository, use the pattern ``**.c``.
 For each file only the first matching filter applies.
 
 The filter command can start with a specifier, either ``pipe:`` or
 ``tempfile:``. If no specifier is given, ``pipe:`` is used by default.
 
 A ``pipe:`` command must accept data on stdin and return the transformed
 data on stdout.
 
 Pipe example::
 
   [encode]
   # uncompress gzip files on checkin to improve delta compression
   # note: not necessarily a good idea, just an example
   *.gz = pipe: gunzip
 
   [decode]
   # recompress gzip files when writing them to the working dir (we
   # can safely omit "pipe:", because it's the default)
   *.gz = gzip
 
 A ``tempfile:`` command is a template. The string ``INFILE`` is replaced
 with the name of a temporary file that contains the data to be
 filtered by the command. The string ``OUTFILE`` is replaced with the name
 of an empty temporary file, where the filtered data must be written by
 the command.
 
 .. note::
 
    The tempfile mechanism is recommended for Windows systems,
    where the standard shell I/O redirection operators often have
    strange effects and may corrupt the contents of your files.
 
 This filter mechanism is used internally by the ``eol`` extension to
 translate line ending characters between Windows (CRLF) and Unix (LF)
 format. We suggest you use the ``eol`` extension for convenience.
 
 
 ``defaults``
 ------------
 
 (defaults are deprecated. Don't use them. Use aliases instead.)
 
 Use the ``[defaults]`` section to define command defaults, i.e. the
 default options/arguments to pass to the specified commands.
 
 The following example makes :hg:`log` run in verbose mode, and
 :hg:`status` show only the modified files, by default::
 
   [defaults]
   log = -v
   status = -m
 
 The actual commands, instead of their aliases, must be used when
 defining command defaults. The command defaults will also be applied
 to the aliases of the commands defined.
 
 
 ``diff``
 --------
 
 Settings used when displaying diffs. Everything except for ``unified``
 is a Boolean and defaults to False. See :hg:`help config.annotate`
 for related options for the annotate command.
 
 ``git``
     Use git extended diff format.
 
 ``nobinary``
     Omit git binary patches.
 
 ``nodates``
     Don't include dates in diff headers.
 
 ``noprefix``
     Omit 'a/' and 'b/' prefixes from filenames. Ignored in plain mode.
 
 ``showfunc``
     Show which function each change is in.
 
 ``ignorews``
     Ignore white space when comparing lines.
 
 ``ignorewsamount``
     Ignore changes in the amount of white space.
 
 ``ignoreblanklines``
     Ignore changes whose lines are all blank.
 
 ``unified``
     Number of lines of context to show.
 
 ``email``
 ---------
 
 Settings for extensions that send email messages.
 
 ``from``
     Optional. Email address to use in "From" header and SMTP envelope
     of outgoing messages.
 
 ``to``
     Optional. Comma-separated list of recipients' email addresses.
 
 ``cc``
     Optional. Comma-separated list of carbon copy recipients'
     email addresses.
 
 ``bcc``
     Optional. Comma-separated list of blind carbon copy recipients'
     email addresses.
 
 ``method``
     Optional. Method to use to send email messages. If value is ``smtp``
     (default), use SMTP (see the ``[smtp]`` section for configuration).
     Otherwise, use as name of program to run that acts like sendmail
     (takes ``-f`` option for sender, list of recipients on command line,
     message on stdin). Normally, setting this to ``sendmail`` or
     ``/usr/sbin/sendmail`` is enough to use sendmail to send messages.
 
 ``charsets``
     Optional. Comma-separated list of character sets considered
     convenient for recipients. Addresses, headers, and parts not
     containing patches of outgoing messages will be encoded in the
     first character set to which conversion from local encoding
     (``$HGENCODING``, ``ui.fallbackencoding``) succeeds. If correct
     conversion fails, the text in question is sent as is.
     (default: '')
 
     Order of outgoing email character sets:
 
     1. ``us-ascii``: always first, regardless of settings
     2. ``email.charsets``: in order given by user
     3. ``ui.fallbackencoding``: if not in email.charsets
     4. ``$HGENCODING``: if not in email.charsets
     5. ``utf-8``: always last, regardless of settings
 
 Email example::
 
   [email]
   from = Joseph User <[e-mail]>
   method = /usr/sbin/sendmail
   # charsets for western Europeans
   # us-ascii, utf-8 omitted, as they are tried first and last
   charsets = iso-8859-1, iso-8859-15, windows-1252
 
 
 ``extensions``
 --------------
 
 Mercurial has an extension mechanism for adding new features. To
 enable an extension, create an entry for it in this section.
 
 If you know that the extension is already in Python's search path,
 you can give the name of the module, followed by ``=``, with nothing
 after the ``=``.
 
 Otherwise, give a name that you choose, followed by ``=``, followed by
 the path to the ``.py`` file (including the file name extension) that
 defines the extension.
 
 To explicitly disable an extension that is enabled in an hgrc of
 broader scope, prepend its path with ``!``, as in ``foo = !/ext/path``
 or ``foo = !`` when path is not supplied.
 
 Example for ``~/.hgrc``::
 
   [extensions]
   # (the color extension will get loaded from Mercurial's path)
   color =
   # (this extension will get loaded from the file specified)
   myfeature = ~/.hgext/myfeature.py
 
 
 ``format``
 ----------
 
 ``usestore``
     Enable or disable the "store" repository format which improves
     compatibility with systems that fold case or otherwise mangle
     filenames. Enabled by default. Disabling this option will allow
     you to store longer filenames in some situations at the expense of
     compatibility and ensures that the on-disk format of newly created
     repositories will be compatible with Mercurial before version 0.9.4.
 
 ``usefncache``
     Enable or disable the "fncache" repository format which enhances
     the "store" repository format (which has to be enabled to use
     fncache) to allow longer filenames and avoids using Windows
     reserved names, e.g. "nul". Enabled by default. Disabling this
     option ensures that the on-disk format of newly created
     repositories will be compatible with Mercurial before version 1.1.
 
 ``dotencode``
     Enable or disable the "dotencode" repository format which enhances
     the "fncache" repository format (which has to be enabled to use
     dotencode) to avoid issues with filenames starting with ._ on
     Mac OS X and spaces on Windows. Enabled by default. Disabling this
     option ensures that the on-disk format of newly created
     repositories will be compatible with Mercurial before version 1.7.
 
 ``graph``
 ---------
 
 Web graph view configuration. This section let you change graph
 elements display properties by branches, for instance to make the
 ``default`` branch stand out.
 
 Each line has the following format::
 
     <branch>.<argument> = <value>
 
 where ``<branch>`` is the name of the branch being
 customized. Example::
 
     [graph]
     # 2px width
     default.width = 2
     # red color
     default.color = FF0000
 
 Supported arguments:
 
 ``width``
     Set branch edges width in pixels.
 
 ``color``
     Set branch edges color in hexadecimal RGB notation.
 
 ``hooks``
 ---------
 
 Commands or Python functions that get automatically executed by
 various actions such as starting or finishing a commit. Multiple
 hooks can be run for the same action by appending a suffix to the
 action. Overriding a site-wide hook can be done by changing its
 value or setting it to an empty string.  Hooks can be prioritized
 by adding a prefix of ``priority`` to the hook name on a new line
 and setting the priority. The default priority is 0.
 
 Example ``.hg/hgrc``::
 
   [hooks]
   # update working directory after adding changesets
   changegroup.update = hg update
   # do not use the site-wide hook
   incoming =
   incoming.email = /my/email/hook
   incoming.autobuild = /my/build/hook
   # force autobuild hook to run before other incoming hooks
   priority.incoming.autobuild = 1
 
 Most hooks are run with environment variables set that give useful
 additional information. For each hook below, the environment
 variables it is passed are listed with names of the form ``$HG_foo``.
 
 ``changegroup``
   Run after a changegroup has been added via push, pull or unbundle.
   ID of the first new changeset is in ``$HG_NODE``. URL from which
   changes came is in ``$HG_URL``.
 
 ``commit``
   Run after a changeset has been created in the local repository. ID
   of the newly created changeset is in ``$HG_NODE``. Parent changeset
   IDs are in ``$HG_PARENT1`` and ``$HG_PARENT2``.
 
 ``incoming``
   Run after a changeset has been pulled, pushed, or unbundled into
   the local repository. The ID of the newly arrived changeset is in
   ``$HG_NODE``. URL that was source of changes came is in ``$HG_URL``.
 
 ``outgoing``
   Run after sending changes from local repository to another. ID of
   first changeset sent is in ``$HG_NODE``. Source of operation is in
   ``$HG_SOURCE``; Also see :hg:`help config.preoutgoing` hook.
 
 ``post-<command>``
   Run after successful invocations of the associated command. The
   contents of the command line are passed as ``$HG_ARGS`` and the result
   code in ``$HG_RESULT``. Parsed command line arguments are passed as
   ``$HG_PATS`` and ``$HG_OPTS``. These contain string representations of
   the python data internally passed to <command>. ``$HG_OPTS`` is a
   dictionary of options (with unspecified options set to their defaults).
   ``$HG_PATS`` is a list of arguments. Hook failure is ignored.
 
 ``pre-<command>``
   Run before executing the associated command. The contents of the
   command line are passed as ``$HG_ARGS``. Parsed command line arguments
   are passed as ``$HG_PATS`` and ``$HG_OPTS``. These contain string
   representations of the data internally passed to <command>. ``$HG_OPTS``
   is a  dictionary of options (with unspecified options set to their
   defaults). ``$HG_PATS`` is a list of arguments. If the hook returns
   failure, the command doesn't execute and Mercurial returns the failure
   code.
 
 ``prechangegroup``
   Run before a changegroup is added via push, pull or unbundle. Exit
   status 0 allows the changegroup to proceed. Non-zero status will
   cause the push, pull or unbundle to fail. URL from which changes
   will come is in ``$HG_URL``.
 
 ``precommit``
   Run before starting a local commit. Exit status 0 allows the
   commit to proceed. Non-zero status will cause the commit to fail.
   Parent changeset IDs are in ``$HG_PARENT1`` and ``$HG_PARENT2``.
 
 ``prelistkeys``
   Run before listing pushkeys (like bookmarks) in the
   repository. Non-zero status will cause failure. The key namespace is
   in ``$HG_NAMESPACE``.
 
 ``preoutgoing``
   Run before collecting changes to send from the local repository to
   another. Non-zero status will cause failure. This lets you prevent
   pull over HTTP or SSH. Also prevents against local pull, push
   (outbound) or bundle commands, but not effective, since you can
   just copy files instead then. Source of operation is in
   ``$HG_SOURCE``. If "serve", operation is happening on behalf of remote
   SSH or HTTP repository. If "push", "pull" or "bundle", operation
   is happening on behalf of repository on same system.
 
 ``prepushkey``
   Run before a pushkey (like a bookmark) is added to the
   repository. Non-zero status will cause the key to be rejected. The
   key namespace is in ``$HG_NAMESPACE``, the key is in ``$HG_KEY``,
   the old value (if any) is in ``$HG_OLD``, and the new value is in
   ``$HG_NEW``.
 
 ``pretag``
   Run before creating a tag. Exit status 0 allows the tag to be
   created. Non-zero status will cause the tag to fail. ID of
   changeset to tag is in ``$HG_NODE``. Name of tag is in ``$HG_TAG``. Tag is
   local if ``$HG_LOCAL=1``, in repository if ``$HG_LOCAL=0``.
 
 ``pretxnopen``
   Run before any new repository transaction is open. The reason for the
   transaction will be in ``$HG_TXNNAME`` and a unique identifier for the
   transaction will be in ``HG_TXNID``. A non-zero status will prevent the
   transaction from being opened.
 
 ``pretxnclose``
   Run right before the transaction is actually finalized. Any
   repository change will be visible to the hook program. This lets you
   validate the transaction content or change it. Exit status 0 allows
   the commit to proceed. Non-zero status will cause the transaction to
   be rolled back. The reason for the transaction opening will be in
   ``$HG_TXNNAME`` and a unique identifier for the transaction will be in
   ``HG_TXNID``. The rest of the available data will vary according the
   transaction type. New changesets will add ``$HG_NODE`` (id of the
   first added changeset), ``$HG_URL`` and ``$HG_SOURCE`` variables,
   bookmarks and phases changes will set ``HG_BOOKMARK_MOVED`` and
   ``HG_PHASES_MOVED`` to ``1``, etc.
 
 ``txnclose``
   Run after any repository transaction has been committed. At this
   point, the transaction can no longer be rolled back. The hook will run
   after the lock is released. See :hg:`help config.pretxnclose` docs for
   details about available variables.
 
 ``txnabort``
   Run when a transaction is aborted. See :hg:`help config.pretxnclose`
   docs for details about available variables.
 
 ``pretxnchangegroup``
   Run after a changegroup has been added via push, pull or unbundle,
   but before the transaction has been committed. Changegroup is
   visible to hook program. This lets you validate incoming changes
   before accepting them. Passed the ID of the first new changeset in
   ``$HG_NODE``. Exit status 0 allows the transaction to commit. Non-zero
   status will cause the transaction to be rolled back and the push,
   pull or unbundle will fail. URL that was source of changes is in
   ``$HG_URL``.
 
 ``pretxncommit``
   Run after a changeset has been created but the transaction not yet
   committed. Changeset is visible to hook program. This lets you
   validate commit message and changes. Exit status 0 allows the
   commit to proceed. Non-zero status will cause the transaction to
   be rolled back. ID of changeset is in ``$HG_NODE``. Parent changeset
   IDs are in ``$HG_PARENT1`` and ``$HG_PARENT2``.
 
 ``preupdate``
   Run before updating the working directory. Exit status 0 allows
   the update to proceed. Non-zero status will prevent the update.
   Changeset ID of first new parent is in ``$HG_PARENT1``. If merge, ID
   of second new parent is in ``$HG_PARENT2``.
 
 ``listkeys``
   Run after listing pushkeys (like bookmarks) in the repository. The
   key namespace is in ``$HG_NAMESPACE``. ``$HG_VALUES`` is a
   dictionary containing the keys and values.
 
 ``pushkey``
   Run after a pushkey (like a bookmark) is added to the
   repository. The key namespace is in ``$HG_NAMESPACE``, the key is in
   ``$HG_KEY``, the old value (if any) is in ``$HG_OLD``, and the new
   value is in ``$HG_NEW``.
 
 ``tag``
   Run after a tag is created. ID of tagged changeset is in ``$HG_NODE``.
   Name of tag is in ``$HG_TAG``. Tag is local if ``$HG_LOCAL=1``, in
   repository if ``$HG_LOCAL=0``.
 
 ``update``
   Run after updating the working directory. Changeset ID of first
   new parent is in ``$HG_PARENT1``. If merge, ID of second new parent is
   in ``$HG_PARENT2``. If the update succeeded, ``$HG_ERROR=0``. If the
   update failed (e.g. because conflicts not resolved), ``$HG_ERROR=1``.
 
 .. note::
 
    It is generally better to use standard hooks rather than the
    generic pre- and post- command hooks as they are guaranteed to be
    called in the appropriate contexts for influencing transactions.
    Also, hooks like "commit" will be called in all contexts that
    generate a commit (e.g. tag) and not just the commit command.
 
 .. note::
 
    Environment variables with empty values may not be passed to
    hooks on platforms such as Windows. As an example, ``$HG_PARENT2``
    will have an empty value under Unix-like platforms for non-merge
    changesets, while it will not be available at all under Windows.
 
 The syntax for Python hooks is as follows::
 
   hookname = python:modulename.submodule.callable
   hookname = python:/path/to/python/module.py:callable
 
 Python hooks are run within the Mercurial process. Each hook is
 called with at least three keyword arguments: a ui object (keyword
 ``ui``), a repository object (keyword ``repo``), and a ``hooktype``
 keyword that tells what kind of hook is used. Arguments listed as
 environment variables above are passed as keyword arguments, with no
 ``HG_`` prefix, and names in lower case.
 
 If a Python hook returns a "true" value or raises an exception, this
 is treated as a failure.
 
 
 ``hostfingerprints``
 --------------------
 
 Fingerprints of the certificates of known HTTPS servers.
 A HTTPS connection to a server with a fingerprint configured here will
 only succeed if the servers certificate matches the fingerprint.
 This is very similar to how ssh known hosts works.
 The fingerprint is the SHA-1 hash value of the DER encoded certificate.
 The CA chain and web.cacerts is not used for servers with a fingerprint.
 
 For example::
 
     [hostfingerprints]
     hg.intevation.org = fa:1f:d9:48:f1:e7:74:30:38:8d:d8:58:b6:94:b8:58:28:7d:8b:d0
 
 This feature is only supported when using Python 2.6 or later.
 
 
 ``http_proxy``
 --------------
 
 Used to access web-based Mercurial repositories through a HTTP
 proxy.
 
 ``host``
     Host name and (optional) port of the proxy server, for example
     "myproxy:8000".
 
 ``no``
     Optional. Comma-separated list of host names that should bypass
     the proxy.
 
 ``passwd``
     Optional. Password to authenticate with at the proxy server.
 
 ``user``
     Optional. User name to authenticate with at the proxy server.
 
 ``always``
     Optional. Always use the proxy, even for localhost and any entries
     in ``http_proxy.no``. (default: False)
 
 ``merge-patterns``
 ------------------
 
 This section specifies merge tools to associate with particular file
 patterns. Tools matched here will take precedence over the default
 merge tool. Patterns are globs by default, rooted at the repository
 root.
 
 Example::
 
   [merge-patterns]
   **.c = kdiff3
   **.jpg = myimgmerge
 
 ``merge-tools``
 ---------------
 
 This section configures external merge tools to use for file-level
 merges. This section has likely been preconfigured at install time.
 Use :hg:`config merge-tools` to check the existing configuration.
 Also see :hg:`help merge-tools` for more details.
 
 Example ``~/.hgrc``::
 
   [merge-tools]
   # Override stock tool location
   kdiff3.executable = ~/bin/kdiff3
   # Specify command line
   kdiff3.args = $base $local $other -o $output
   # Give higher priority
   kdiff3.priority = 1
 
   # Changing the priority of preconfigured tool
   vimdiff.priority = 0
 
   # Define new tool
   myHtmlTool.args = -m $local $other $base $output
   myHtmlTool.regkey = Software\FooSoftware\HtmlMerge
   myHtmlTool.priority = 1
 
 Supported arguments:
 
 ``priority``
   The priority in which to evaluate this tool.
   (default: 0)
 
 ``executable``
   Either just the name of the executable or its pathname.  On Windows,
   the path can use environment variables with ${ProgramFiles} syntax.
   (default: the tool name)
 
 ``args``
   The arguments to pass to the tool executable. You can refer to the
   files being merged as well as the output file through these
   variables: ``$base``, ``$local``, ``$other``, ``$output``. The meaning
   of ``$local`` and ``$other`` can vary depending on which action is being
   performed. During and update or merge, ``$local`` represents the original
   state of the file, while ``$other`` represents the commit you are updating
   to or the commit you are merging with. During a rebase ``$local``
   represents the destination of the rebase, and ``$other`` represents the
   commit being rebased.
   (default: ``$local $base $other``)
 
 ``premerge``
   Attempt to run internal non-interactive 3-way merge tool before
   launching external tool.  Options are ``true``, ``false``, ``keep`` or
   ``keep-merge3``. The ``keep`` option will leave markers in the file if the
   premerge fails. The ``keep-merge3`` will do the same but include information
   about the base of the merge in the marker (see internal :merge3 in
   :hg:`help merge-tools`).
   (default: True)
 
 ``binary``
   This tool can merge binary files. (default: False, unless tool
   was selected by file pattern match)
 
 ``symlink``
   This tool can merge symlinks. (default: False)
 
 ``check``
   A list of merge success-checking options:
 
   ``changed``
     Ask whether merge was successful when the merged file shows no changes.
   ``conflicts``
     Check whether there are conflicts even though the tool reported success.
   ``prompt``
     Always prompt for merge success, regardless of success reported by tool.
 
 ``fixeol``
   Attempt to fix up EOL changes caused by the merge tool.
   (default: False)
 
 ``gui``
   This tool requires a graphical interface to run. (default: False)
 
 ``regkey``
   Windows registry key which describes install location of this
   tool. Mercurial will search for this key first under
   ``HKEY_CURRENT_USER`` and then under ``HKEY_LOCAL_MACHINE``.
   (default: None)
 
 ``regkeyalt``
   An alternate Windows registry key to try if the first key is not
   found.  The alternate key uses the same ``regname`` and ``regappend``
   semantics of the primary key.  The most common use for this key
   is to search for 32bit applications on 64bit operating systems.
   (default: None)
 
 ``regname``
   Name of value to read from specified registry key.
   (default: the unnamed (default) value)
 
 ``regappend``
   String to append to the value read from the registry, typically
   the executable name of the tool.
   (default: None)
 
 
 ``patch``
 ---------
 
 Settings used when applying patches, for instance through the 'import'
 command or with Mercurial Queues extension.
 
 ``eol``
     When set to 'strict' patch content and patched files end of lines
     are preserved. When set to ``lf`` or ``crlf``, both files end of
     lines are ignored when patching and the result line endings are
     normalized to either LF (Unix) or CRLF (Windows). When set to
     ``auto``, end of lines are again ignored while patching but line
     endings in patched files are normalized to their original setting
     on a per-file basis. If target file does not exist or has no end
     of line, patch line endings are preserved.
     (default: strict)
 
 ``fuzz``
     The number of lines of 'fuzz' to allow when applying patches. This
     controls how much context the patcher is allowed to ignore when
     trying to apply a patch.
     (default: 2)
 
 ``paths``
 ---------
 
 Assigns symbolic names to repositories. The left side is the
 symbolic name, and the right gives the directory or URL that is the
 location of the repository. Default paths can be declared by setting
 the following entries.
 
 ``default``
     Directory or URL to use when pulling if no source is specified.
     (default: repository from which the current repository was cloned)
 
 ``default-push``
     Optional. Directory or URL to use when pushing if no destination
     is specified.
 
 Custom paths can be defined by assigning the path to a name that later can be
 used from the command line. Example::
 
     [paths]
     my_path = http://example.com/path
 
 To push to the path defined in ``my_path`` run the command::
 
     hg push my_path
 
 
 ``phases``
 ----------
 
 Specifies default handling of phases. See :hg:`help phases` for more
 information about working with phases.
 
 ``publish``
     Controls draft phase behavior when working as a server. When true,
     pushed changesets are set to public in both client and server and
     pulled or cloned changesets are set to public in the client.
     (default: True)
 
 ``new-commit``
     Phase of newly-created commits.
     (default: draft)
 
 ``checksubrepos``
     Check the phase of the current revision of each subrepository. Allowed
     values are "ignore", "follow" and "abort". For settings other than
     "ignore", the phase of the current revision of each subrepository is
     checked before committing the parent repository. If any of those phases is
     greater than the phase of the parent repository (e.g. if a subrepo is in a
     "secret" phase while the parent repo is in "draft" phase), the commit is
     either aborted (if checksubrepos is set to "abort") or the higher phase is
     used for the parent repository commit (if set to "follow").
     (default: follow)
 
 
 ``profiling``
 -------------
 
 Specifies profiling type, format, and file output. Two profilers are
 supported: an instrumenting profiler (named ``ls``), and a sampling
 profiler (named ``stat``).
 
 In this section description, 'profiling data' stands for the raw data
 collected during profiling, while 'profiling report' stands for a
 statistical text report generated from the profiling data. The
 profiling is done using lsprof.
 
 ``type``
     The type of profiler to use.
     (default: ls)
 
     ``ls``
       Use Python's built-in instrumenting profiler. This profiler
       works on all platforms, but each line number it reports is the
       first line of a function. This restriction makes it difficult to
       identify the expensive parts of a non-trivial function.
     ``stat``
       Use a third-party statistical profiler, statprof. This profiler
       currently runs only on Unix systems, and is most useful for
       profiling commands that run for longer than about 0.1 seconds.
 
 ``format``
     Profiling format.  Specific to the ``ls`` instrumenting profiler.
     (default: text)
 
     ``text``
       Generate a profiling report. When saving to a file, it should be
       noted that only the report is saved, and the profiling data is
       not kept.
     ``kcachegrind``
       Format profiling data for kcachegrind use: when saving to a
       file, the generated file can directly be loaded into
       kcachegrind.
 
 ``frequency``
     Sampling frequency.  Specific to the ``stat`` sampling profiler.
     (default: 1000)
 
 ``output``
     File path where profiling data or report should be saved. If the
     file exists, it is replaced. (default: None, data is printed on
     stderr)
 
 ``sort``
     Sort field.  Specific to the ``ls`` instrumenting profiler.
     One of ``callcount``, ``reccallcount``, ``totaltime`` and
     ``inlinetime``.
     (default: inlinetime)
 
 ``limit``
     Number of lines to show. Specific to the ``ls`` instrumenting profiler.
     (default: 30)
 
 ``nested``
     Show at most this number of lines of drill-down info after each main entry.
     This can help explain the difference between Total and Inline.
     Specific to the ``ls`` instrumenting profiler.
     (default: 5)
 
 ``progress``
 ------------
 
 Mercurial commands can draw progress bars that are as informative as
 possible. Some progress bars only offer indeterminate information, while others
 have a definite end point.
 
 ``delay``
     Number of seconds (float) before showing the progress bar. (default: 3)
 
 ``changedelay``
     Minimum delay before showing a new topic. When set to less than 3 * refresh,
     that value will be used instead. (default: 1)
 
 ``refresh``
     Time in seconds between refreshes of the progress bar. (default: 0.1)
 
 ``format``
     Format of the progress bar.
 
     Valid entries for the format field are ``topic``, ``bar``, ``number``,
     ``unit``, ``estimate``, speed, and item. item defaults to the last 20
     characters of the item, but this can be changed by adding either ``-<num>``
     which would take the last num characters, or ``+<num>`` for the first num
     characters.
 
     (default: Topic bar number estimate)
 
 ``width``
     If set, the maximum width of the progress information (that is, min(width,
     term width) will be used).
 
 ``clear-complete``
     Clear the progress bar after it's done. (default: True)
 
 ``disable``
     If true, don't show a progress bar.
 
 ``assume-tty``
     If true, ALWAYS show a progress bar, unless disable is given.
 
 ``revsetalias``
 ---------------
 
 Alias definitions for revsets. See :hg:`help revsets` for details.
 
 ``server``
 ----------
 
 Controls generic server settings.
 
 ``uncompressed``
     Whether to allow clients to clone a repository using the
     uncompressed streaming protocol. This transfers about 40% more
     data than a regular clone, but uses less memory and CPU on both
     server and client. Over a LAN (100 Mbps or better) or a very fast
     WAN, an uncompressed streaming clone is a lot faster (~10x) than a
     regular clone. Over most WAN connections (anything slower than
     about 6 Mbps), uncompressed streaming is slower, because of the
     extra data transfer overhead. This mode will also temporarily hold
     the write lock while determining what data to transfer.
     (default: True)
 
 ``preferuncompressed``
     When set, clients will try to use the uncompressed streaming
     protocol. (default: False)
 
 ``validate``
     Whether to validate the completeness of pushed changesets by
     checking that all new file revisions specified in manifests are
     present. (default: False)
 
 ``maxhttpheaderlen``
     Instruct HTTP clients not to send request headers longer than this
     many bytes. (default: 1024)
 
 ``smtp``
 --------
 
 Configuration for extensions that need to send email messages.
 
 ``host``
     Host name of mail server, e.g. "mail.example.com".
 
 ``port``
     Optional. Port to connect to on mail server. (default: 465 if
     ``tls`` is smtps; 25 otherwise)
 
 ``tls``
     Optional. Method to enable TLS when connecting to mail server: starttls,
     smtps or none. (default: none)
 
 ``verifycert``
     Optional. Verification for the certificate of mail server, when
     ``tls`` is starttls or smtps. "strict", "loose" or False. For
     "strict" or "loose", the certificate is verified as same as the
     verification for HTTPS connections (see ``[hostfingerprints]`` and
     ``[web] cacerts`` also). For "strict", sending email is also
     aborted, if there is no configuration for mail server in
     ``[hostfingerprints]`` and ``[web] cacerts``.  --insecure for
     :hg:`email` overwrites this as "loose". (default: strict)
 
 ``username``
     Optional. User name for authenticating with the SMTP server.
     (default: None)
 
 ``password``
     Optional. Password for authenticating with the SMTP server. If not
     specified, interactive sessions will prompt the user for a
     password; non-interactive sessions will fail. (default: None)
 
 ``local_hostname``
     Optional. The hostname that the sender can use to identify
     itself to the MTA.
 
 
 ``subpaths``
 ------------
 
 Subrepository source URLs can go stale if a remote server changes name
 or becomes temporarily unavailable. This section lets you define
 rewrite rules of the form::
 
     <pattern> = <replacement>
 
 where ``pattern`` is a regular expression matching a subrepository
 source URL and ``replacement`` is the replacement string used to
 rewrite it. Groups can be matched in ``pattern`` and referenced in
 ``replacements``. For instance::
 
     http://server/(.*)-hg/ = http://hg.server/\1/
 
 rewrites ``http://server/foo-hg/`` into ``http://hg.server/foo/``.
 
 Relative subrepository paths are first made absolute, and the
 rewrite rules are then applied on the full (absolute) path. The rules
 are applied in definition order.
 
 ``trusted``
 -----------
 
 Mercurial will not use the settings in the
 ``.hg/hgrc`` file from a repository if it doesn't belong to a trusted
 user or to a trusted group, as various hgrc features allow arbitrary
 commands to be run. This issue is often encountered when configuring
 hooks or extensions for shared repositories or servers. However,
 the web interface will use some safe settings from the ``[web]``
 section.
 
 This section specifies what users and groups are trusted. The
 current user is always trusted. To trust everybody, list a user or a
 group with name ``*``. These settings must be placed in an
 *already-trusted file* to take effect, such as ``$HOME/.hgrc`` of the
 user or service running Mercurial.
 
 ``users``
   Comma-separated list of trusted users.
 
 ``groups``
   Comma-separated list of trusted groups.
 
 
 ``ui``
 ------
 
 User interface controls.
 
 ``archivemeta``
     Whether to include the .hg_archival.txt file containing meta data
     (hashes for the repository base and for tip) in archives created
     by the :hg:`archive` command or downloaded via hgweb.
     (default: True)
 
 ``askusername``
     Whether to prompt for a username when committing. If True, and
     neither ``$HGUSER`` nor ``$EMAIL`` has been specified, then the user will
     be prompted to enter a username. If no username is entered, the
     default ``USER@HOST`` is used instead.
     (default: False)
 
+``clonebundlefallback``
+    Whether failure to apply an advertised "clone bundle" from a server
+    should result in fallback to a regular clone.
+
+    This is disabled by default because servers advertising "clone
+    bundles" often do so to reduce server load. If advertised bundles
+    start mass failing and clients automatically fall back to a regular
+    clone, this would add significant and unexpected load to the server
+    since the server is expecting clone operations to be offloaded to
+    pre-generated bundles. Failing fast (the default behavior) ensures
+    clients don't overwhelm the server when "clone bundle" application
+    fails.
+
+    (default: False)
+
 ``commitsubrepos``
     Whether to commit modified subrepositories when committing the
     parent repository. If False and one subrepository has uncommitted
     changes, abort the commit.
     (default: False)
 
 ``debug``
     Print debugging information. (default: False)
 
 ``editor``
     The editor to use during a commit. (default: ``$EDITOR`` or ``vi``)
 
 ``fallbackencoding``
     Encoding to try if it's not possible to decode the changelog using
     UTF-8. (default: ISO-8859-1)
 
 ``ignore``
     A file to read per-user ignore patterns from. This file should be
     in the same format as a repository-wide .hgignore file. Filenames
     are relative to the repository root. This option supports hook syntax,
     so if you want to specify multiple ignore files, you can do so by
     setting something like ``ignore.other = ~/.hgignore2``. For details
     of the ignore file format, see the ``hgignore(5)`` man page.
 
 ``interactive``
     Allow to prompt the user. (default: True)
 
 ``logtemplate``
     Template string for commands that print changesets.
 
 ``merge``
     The conflict resolution program to use during a manual merge.
     For more information on merge tools see :hg:`help merge-tools`.
     For configuring merge tools see the ``[merge-tools]`` section.
 
 ``mergemarkers``
     Sets the merge conflict marker label styling. The ``detailed``
     style uses the ``mergemarkertemplate`` setting to style the labels.
     The ``basic`` style just uses 'local' and 'other' as the marker label.
     One of ``basic`` or ``detailed``.
     (default: ``basic``)
 
 ``mergemarkertemplate``
     The template used to print the commit description next to each conflict
     marker during merge conflicts. See :hg:`help templates` for the template
     format.
 
     Defaults to showing the hash, tags, branches, bookmarks, author, and
     the first line of the commit description.
 
     If you use non-ASCII characters in names for tags, branches, bookmarks,
     authors, and/or commit descriptions, you must pay attention to encodings of
     managed files. At template expansion, non-ASCII characters use the encoding
     specified by the ``--encoding`` global option, ``HGENCODING`` or other
     environment variables that govern your locale. If the encoding of the merge
     markers is different from the encoding of the merged files,
     serious problems may occur.
 
 ``patch``
     An optional external tool that ``hg import`` and some extensions
     will use for applying patches. By default Mercurial uses an
     internal patch utility. The external tool must work as the common
     Unix ``patch`` program. In particular, it must accept a ``-p``
     argument to strip patch headers, a ``-d`` argument to specify the
     current directory, a file name to patch, and a patch file to take
     from stdin.
 
     It is possible to specify a patch tool together with extra
     arguments. For example, setting this option to ``patch --merge``
     will use the ``patch`` program with its 2-way merge option.
 
 ``portablefilenames``
     Check for portable filenames. Can be ``warn``, ``ignore`` or ``abort``.
     (default: ``warn``)
     If set to ``warn`` (or ``true``), a warning message is printed on POSIX
     platforms, if a file with a non-portable filename is added (e.g. a file
     with a name that can't be created on Windows because it contains reserved
     parts like ``AUX``, reserved characters like ``:``, or would cause a case
     collision with an existing file).
     If set to ``ignore`` (or ``false``), no warning is printed.
     If set to ``abort``, the command is aborted.
     On Windows, this configuration option is ignored and the command aborted.
 
 ``quiet``
     Reduce the amount of output printed. (default: False)
 
 ``remotecmd``
     Remote command to use for clone/push/pull operations. (default: ``hg``)
 
 ``report_untrusted``
     Warn if a ``.hg/hgrc`` file is ignored due to not being owned by a
     trusted user or group. (default: True)
 
 ``slash``
     Display paths using a slash (``/``) as the path separator. This
     only makes a difference on systems where the default path
     separator is not the slash character (e.g. Windows uses the
     backslash character (``\``)).
     (default: False)
 
 ``statuscopies``
     Display copies in the status command.
 
 ``ssh``
     Command to use for SSH connections. (default: ``ssh``)
 
 ``strict``
     Require exact command names, instead of allowing unambiguous
     abbreviations. (default: False)
 
 ``style``
     Name of style to use for command output.
 
 ``supportcontact``
     A URL where users should report a Mercurial traceback. Use this if you are a
     large organisation with its own Mercurial deployment process and crash
     reports should be addressed to your internal support.
 
 ``timeout``
     The timeout used when a lock is held (in seconds), a negative value
     means no timeout. (default: 600)
 
 ``traceback``
     Mercurial always prints a traceback when an unknown exception
     occurs. Setting this to True will make Mercurial print a traceback
     on all exceptions, even those recognized by Mercurial (such as
     IOError or MemoryError). (default: False)
 
 ``username``
     The committer of a changeset created when running "commit".
     Typically a person's name and email address, e.g. ``Fred Widget
     <[e-mail]>``. Environment variables in the
     username are expanded.
 
     (default: ``$EMAIL`` or ``username@hostname``. If the username in
     hgrc is empty, e.g. if the system admin set ``username =``  in the
     system hgrc, it has to be specified manually or in a different
     hgrc file)
 
 ``verbose``
     Increase the amount of output printed. (default: False)
 
 
 ``web``
 -------
 
 Web interface configuration. The settings in this section apply to
 both the builtin webserver (started by :hg:`serve`) and the script you
 run through a webserver (``hgweb.cgi`` and the derivatives for FastCGI
 and WSGI).
 
 The Mercurial webserver does no authentication (it does not prompt for
 usernames and passwords to validate *who* users are), but it does do
 authorization (it grants or denies access for *authenticated users*
 based on settings in this section). You must either configure your
 webserver to do authentication for you, or disable the authorization
 checks.
 
 For a quick setup in a trusted environment, e.g., a private LAN, where
 you want it to accept pushes from anybody, you can use the following
 command line::
 
     $ hg --config web.allow_push=* --config web.push_ssl=False serve
 
 Note that this will allow anybody to push anything to the server and
 that this should not be used for public servers.
 
 The full set of options is:
 
 ``accesslog``
     Where to output the access log. (default: stdout)
 
 ``address``
     Interface address to bind to. (default: all)
 
 ``allow_archive``
     List of archive format (bz2, gz, zip) allowed for downloading.
     (default: empty)
 
 ``allowbz2``
     (DEPRECATED) Whether to allow .tar.bz2 downloading of repository
     revisions.
     (default: False)
 
 ``allowgz``
     (DEPRECATED) Whether to allow .tar.gz downloading of repository
     revisions.
     (default: False)
 
 ``allowpull``
     Whether to allow pulling from the repository. (default: True)
 
 ``allow_push``
     Whether to allow pushing to the repository. If empty or not set,
     pushing is not allowed. If the special value ``*``, any remote
     user can push, including unauthenticated users. Otherwise, the
     remote user must have been authenticated, and the authenticated
     user name must be present in this list. The contents of the
     allow_push list are examined after the deny_push list.
 
 ``allow_read``
     If the user has not already been denied repository access due to
     the contents of deny_read, this list determines whether to grant
     repository access to the user. If this list is not empty, and the
     user is unauthenticated or not present in the list, then access is
     denied for the user. If the list is empty or not set, then access
     is permitted to all users by default. Setting allow_read to the
     special value ``*`` is equivalent to it not being set (i.e. access
     is permitted to all users). The contents of the allow_read list are
     examined after the deny_read list.
 
 ``allowzip``
     (DEPRECATED) Whether to allow .zip downloading of repository
     revisions. This feature creates temporary files.
     (default: False)
 
 ``archivesubrepos``
     Whether to recurse into subrepositories when archiving.
     (default: False)
 
 ``baseurl``
     Base URL to use when publishing URLs in other locations, so
     third-party tools like email notification hooks can construct
     URLs. Example: ``http://hgserver/repos/``.
 
 ``cacerts``
     Path to file containing a list of PEM encoded certificate
     authority certificates. Environment variables and ``~user``
     constructs are expanded in the filename. If specified on the
     client, then it will verify the identity of remote HTTPS servers
     with these certificates.
 
     This feature is only supported when using Python 2.6 or later. If you wish
     to use it with earlier versions of Python, install the backported
     version of the ssl library that is available from
     ``http://pypi.python.org``.
 
     To disable SSL verification temporarily, specify ``--insecure`` from
     command line.
 
     You can use OpenSSL's CA certificate file if your platform has
     one. On most Linux systems this will be
     ``/etc/ssl/certs/ca-certificates.crt``. Otherwise you will have to
     generate this file manually. The form must be as follows::
 
         -----BEGIN CERTIFICATE-----
         ... (certificate in base64 PEM encoding) ...
         -----END CERTIFICATE-----
         -----BEGIN CERTIFICATE-----
         ... (certificate in base64 PEM encoding) ...
         -----END CERTIFICATE-----
 
 ``cache``
     Whether to support caching in hgweb. (default: True)
 
 ``certificate``
     Certificate to use when running :hg:`serve`.
 
 ``collapse``
     With ``descend`` enabled, repositories in subdirectories are shown at
     a single level alongside repositories in the current path. With
     ``collapse`` also enabled, repositories residing at a deeper level than
     the current path are grouped behind navigable directory entries that
     lead to the locations of these repositories. In effect, this setting
     collapses each collection of repositories found within a subdirectory
     into a single entry for that subdirectory. (default: False)
 
 ``comparisoncontext``
     Number of lines of context to show in side-by-side file comparison. If
     negative or the value ``full``, whole files are shown. (default: 5)
 
     This setting can be overridden by a ``context`` request parameter to the
     ``comparison`` command, taking the same values.
 
 ``contact``
     Name or email address of the person in charge of the repository.
     (default: ui.username or ``$EMAIL`` or "unknown" if unset or empty)
 
 ``deny_push``
     Whether to deny pushing to the repository. If empty or not set,
     push is not denied. If the special value ``*``, all remote users are
     denied push. Otherwise, unauthenticated users are all denied, and
     any authenticated user name present in this list is also denied. The
     contents of the deny_push list are examined before the allow_push list.
 
 ``deny_read``
     Whether to deny reading/viewing of the repository. If this list is
     not empty, unauthenticated users are all denied, and any
     authenticated user name present in this list is also denied access to
     the repository. If set to the special value ``*``, all remote users
     are denied access (rarely needed ;). If deny_read is empty or not set,
     the determination of repository access depends on the presence and
     content of the allow_read list (see description). If both
     deny_read and allow_read are empty or not set, then access is
     permitted to all users by default. If the repository is being
     served via hgwebdir, denied users will not be able to see it in
     the list of repositories. The contents of the deny_read list have
     priority over (are examined before) the contents of the allow_read
     list.
 
 ``descend``
     hgwebdir indexes will not descend into subdirectories. Only repositories
     directly in the current path will be shown (other repositories are still
     available from the index corresponding to their containing path).
 
 ``description``
     Textual description of the repository's purpose or contents.
     (default: "unknown")
 
 ``encoding``
     Character encoding name. (default: the current locale charset)
     Example: "UTF-8".
 
 ``errorlog``
     Where to output the error log. (default: stderr)
 
 ``guessmime``
     Control MIME types for raw download of file content.
     Set to True to let hgweb guess the content type from the file
     extension. This will serve HTML files as ``text/html`` and might
     allow cross-site scripting attacks when serving untrusted
     repositories. (default: False)
 
 ``hidden``
     Whether to hide the repository in the hgwebdir index.
     (default: False)
 
 ``ipv6``
     Whether to use IPv6. (default: False)
 
 ``logoimg``
     File name of the logo image that some templates display on each page.
     The file name is relative to ``staticurl``. That is, the full path to
     the logo image is "staticurl/logoimg".
     If unset, ``hglogo.png`` will be used.
 
 ``logourl``
     Base URL to use for logos. If unset, ``https://mercurial-scm.org/``
     will be used.
 
 ``maxchanges``
     Maximum number of changes to list on the changelog. (default: 10)
 
 ``maxfiles``
     Maximum number of files to list per changeset. (default: 10)
 
 ``maxshortchanges``
     Maximum number of changes to list on the shortlog, graph or filelog
     pages. (default: 60)
 
 ``name``
     Repository name to use in the web interface.
     (default: current working directory)
 
 ``port``
     Port to listen on. (default: 8000)
 
 ``prefix``
     Prefix path to serve from. (default: '' (server root))
 
 ``push_ssl``
     Whether to require that inbound pushes be transported over SSL to
     prevent password sniffing. (default: True)
 
 ``refreshinterval``
     How frequently directory listings re-scan the filesystem for new
     repositories, in seconds. This is relevant when wildcards are used
     to define paths. Depending on how much filesystem traversal is
     required, refreshing may negatively impact performance.
 
     Values less than or equal to 0 always refresh.
     (default: 20)
 
 ``staticurl``
     Base URL to use for static files. If unset, static files (e.g. the
     hgicon.png favicon) will be served by the CGI script itself. Use
     this setting to serve them directly with the HTTP server.
     Example: ``http://hgserver/static/``.
 
 ``stripes``
     How many lines a "zebra stripe" should span in multi-line output.
     Set to 0 to disable. (default: 1)
 
 ``style``
     Which template map style to use. The available options are the names of
     subdirectories in the HTML templates path. (default: ``paper``)
     Example: ``monoblue``.
 
 ``templates``
     Where to find the HTML templates. The default path to the HTML templates
     can be obtained from ``hg debuginstall``.
 
 ``websub``
 ----------
 
 Web substitution filter definition. You can use this section to
 define a set of regular expression substitution patterns which
 let you automatically modify the hgweb server output.
 
 The default hgweb templates only apply these substitution patterns
 on the revision description fields. You can apply them anywhere
 you want when you create your own templates by adding calls to the
 "websub" filter (usually after calling the "escape" filter).
 
 This can be used, for example, to convert issue references to links
 to your issue tracker, or to convert "markdown-like" syntax into
 HTML (see the examples below).
 
 Each entry in this section names a substitution filter.
 The value of each entry defines the substitution expression itself.
 The websub expressions follow the old interhg extension syntax,
 which in turn imitates the Unix sed replacement syntax::
 
     patternname = s/SEARCH_REGEX/REPLACE_EXPRESSION/[i]
 
 You can use any separator other than "/". The final "i" is optional
 and indicates that the search must be case insensitive.
 
 Examples::
 
     [websub]
     issues = s|issue(\d+)|<a href="http://bts.example.org/issue\1">issue\1</a>|i
     italic = s/\b_(\S+)_\b/<i>\1<\/i>/
     bold = s/\*\b(\S+)\b\*/<b>\1<\/b>/
 
 ``worker``
 ----------
 
 Parallel master/worker configuration. We currently perform working
 directory updates in parallel on Unix-like systems, which greatly
 helps performance.
 
 ``numcpus``
     Number of CPUs to use for parallel operations. A zero or
     negative value is treated as ``use the default``.
     (default: 4 or the number of CPUs on the system, whichever is larger)

tests/test-help.t

@@ -1,2377 +1,2381
 Short help:
 
   $ hg
   Mercurial Distributed SCM
   
   basic commands:
   
    add           add the specified files on the next commit
    annotate      show changeset information by line for each file
    clone         make a copy of an existing repository
    commit        commit the specified files or all outstanding changes
    diff          diff repository (or selected files)
    export        dump the header and diffs for one or more changesets
    forget        forget the specified files on the next commit
    init          create a new repository in the given directory
    log           show revision history of entire repository or files
    merge         merge another revision into working directory
    pull          pull changes from the specified source
    push          push changes to the specified destination
    remove        remove the specified files on the next commit
    serve         start stand-alone webserver
    status        show changed files in the working directory
    summary       summarize working directory state
    update        update working directory (or switch revisions)
   
   (use "hg help" for the full list of commands or "hg -v" for details)
 
   $ hg -q
    add           add the specified files on the next commit
    annotate      show changeset information by line for each file
    clone         make a copy of an existing repository
    commit        commit the specified files or all outstanding changes
    diff          diff repository (or selected files)
    export        dump the header and diffs for one or more changesets
    forget        forget the specified files on the next commit
    init          create a new repository in the given directory
    log           show revision history of entire repository or files
    merge         merge another revision into working directory
    pull          pull changes from the specified source
    push          push changes to the specified destination
    remove        remove the specified files on the next commit
    serve         start stand-alone webserver
    status        show changed files in the working directory
    summary       summarize working directory state
    update        update working directory (or switch revisions)
 
   $ hg help
   Mercurial Distributed SCM
   
   list of commands:
   
    add           add the specified files on the next commit
    addremove     add all new files, delete all missing files
    annotate      show changeset information by line for each file
    archive       create an unversioned archive of a repository revision
    backout       reverse effect of earlier changeset
    bisect        subdivision search of changesets
    bookmarks     create a new bookmark or list existing bookmarks
    branch        set or show the current branch name
    branches      list repository named branches
    bundle        create a changegroup file
    cat           output the current or given revision of files
    clone         make a copy of an existing repository
    commit        commit the specified files or all outstanding changes
    config        show combined config settings from all hgrc files
    copy          mark files as copied for the next commit
    diff          diff repository (or selected files)
    export        dump the header and diffs for one or more changesets
    files         list tracked files
    forget        forget the specified files on the next commit
    graft         copy changes from other branches onto the current branch
    grep          search for a pattern in specified files and revisions
    heads         show branch heads
    help          show help for a given topic or a help overview
    identify      identify the working directory or specified revision
    import        import an ordered set of patches
    incoming      show new changesets found in source
    init          create a new repository in the given directory
    log           show revision history of entire repository or files
    manifest      output the current or given revision of the project manifest
    merge         merge another revision into working directory
    outgoing      show changesets not found in the destination
    paths         show aliases for remote repositories
    phase         set or show the current phase name
    pull          pull changes from the specified source
    push          push changes to the specified destination
    recover       roll back an interrupted transaction
    remove        remove the specified files on the next commit
    rename        rename files; equivalent of copy + remove
    resolve       redo merges or set/view the merge status of files
    revert        restore files to their checkout state
    root          print the root (top) of the current working directory
    serve         start stand-alone webserver
    status        show changed files in the working directory
    summary       summarize working directory state
    tag           add one or more tags for the current or given revision
    tags          list repository tags
    unbundle      apply one or more changegroup files
    update        update working directory (or switch revisions)
    verify        verify the integrity of the repository
    version       output version and copyright information
   
   additional help topics:
   
    config        Configuration Files
    dates         Date Formats
    diffs         Diff Formats
    environment   Environment Variables
    extensions    Using Additional Features
    filesets      Specifying File Sets
    glossary      Glossary
    hgignore      Syntax for Mercurial Ignore Files
    hgweb         Configuring hgweb
    merge-tools   Merge Tools
    multirevs     Specifying Multiple Revisions
    patterns      File Name Patterns
    phases        Working with Phases
    revisions     Specifying Single Revisions
    revsets       Specifying Revision Sets
    scripting     Using Mercurial from scripts and automation
    subrepos      Subrepositories
    templating    Template Usage
    urls          URL Paths
   
   (use "hg help -v" to show built-in aliases and global options)
 
   $ hg -q help
    add           add the specified files on the next commit
    addremove     add all new files, delete all missing files
    annotate      show changeset information by line for each file
    archive       create an unversioned archive of a repository revision
    backout       reverse effect of earlier changeset
    bisect        subdivision search of changesets
    bookmarks     create a new bookmark or list existing bookmarks
    branch        set or show the current branch name
    branches      list repository named branches
    bundle        create a changegroup file
    cat           output the current or given revision of files
    clone         make a copy of an existing repository
    commit        commit the specified files or all outstanding changes
    config        show combined config settings from all hgrc files
    copy          mark files as copied for the next commit
    diff          diff repository (or selected files)
    export        dump the header and diffs for one or more changesets
    files         list tracked files
    forget        forget the specified files on the next commit
    graft         copy changes from other branches onto the current branch
    grep          search for a pattern in specified files and revisions
    heads         show branch heads
    help          show help for a given topic or a help overview
    identify      identify the working directory or specified revision
    import        import an ordered set of patches
    incoming      show new changesets found in source
    init          create a new repository in the given directory
    log           show revision history of entire repository or files
    manifest      output the current or given revision of the project manifest
    merge         merge another revision into working directory
    outgoing      show changesets not found in the destination
    paths         show aliases for remote repositories
    phase         set or show the current phase name
    pull          pull changes from the specified source
    push          push changes to the specified destination
    recover       roll back an interrupted transaction
    remove        remove the specified files on the next commit
    rename        rename files; equivalent of copy + remove
    resolve       redo merges or set/view the merge status of files
    revert        restore files to their checkout state
    root          print the root (top) of the current working directory
    serve         start stand-alone webserver
    status        show changed files in the working directory
    summary       summarize working directory state
    tag           add one or more tags for the current or given revision
    tags          list repository tags
    unbundle      apply one or more changegroup files
    update        update working directory (or switch revisions)
    verify        verify the integrity of the repository
    version       output version and copyright information
   
   additional help topics:
   
    config        Configuration Files
    dates         Date Formats
    diffs         Diff Formats
    environment   Environment Variables
    extensions    Using Additional Features
    filesets      Specifying File Sets
    glossary      Glossary
    hgignore      Syntax for Mercurial Ignore Files
    hgweb         Configuring hgweb
    merge-tools   Merge Tools
    multirevs     Specifying Multiple Revisions
    patterns      File Name Patterns
    phases        Working with Phases
    revisions     Specifying Single Revisions
    revsets       Specifying Revision Sets
    scripting     Using Mercurial from scripts and automation
    subrepos      Subrepositories
    templating    Template Usage
    urls          URL Paths
 
 Test extension help:
   $ hg help extensions --config extensions.rebase= --config extensions.children=
   Using Additional Features
   """""""""""""""""""""""""
   
       Mercurial has the ability to add new features through the use of
       extensions. Extensions may add new commands, add options to existing
       commands, change the default behavior of commands, or implement hooks.
   
       To enable the "foo" extension, either shipped with Mercurial or in the
       Python search path, create an entry for it in your configuration file,
       like this:
   
         [extensions]
         foo =
   
       You may also specify the full path to an extension:
   
         [extensions]
         myfeature = ~/.hgext/myfeature.py
   
       See "hg help config" for more information on configuration files.
   
       Extensions are not loaded by default for a variety of reasons: they can
       increase startup overhead; they may be meant for advanced usage only; they
       may provide potentially dangerous abilities (such as letting you destroy
       or modify history); they might not be ready for prime time; or they may
       alter some usual behaviors of stock Mercurial. It is thus up to the user
       to activate extensions as needed.
   
       To explicitly disable an extension enabled in a configuration file of
       broader scope, prepend its path with !:
   
         [extensions]
         # disabling extension bar residing in /path/to/extension/bar.py
         bar = !/path/to/extension/bar.py
         # ditto, but no path was supplied for extension baz
         baz = !
   
       enabled extensions:
   
        children      command to display child changesets (DEPRECATED)
        rebase        command to move sets of revisions to a different ancestor
   
       disabled extensions:
   
        acl           hooks for controlling repository access
        blackbox      log repository events to a blackbox for debugging
        bugzilla      hooks for integrating with the Bugzilla bug tracker
        censor        erase file content at a given revision
        churn         command to display statistics about repository history
+       clonebundles  server side extension to advertise pre-generated bundles to
+                     seed clones.
        color         colorize output from some commands
        convert       import revisions from foreign VCS repositories into
                      Mercurial
        eol           automatically manage newlines in repository files
        extdiff       command to allow external programs to compare revisions
        factotum      http authentication with factotum
        gpg           commands to sign and verify changesets
        hgcia         hooks for integrating with the CIA.vc notification service
        hgk           browse the repository in a graphical way
        highlight     syntax highlighting for hgweb (requires Pygments)
        histedit      interactive history editing
        keyword       expand keywords in tracked files
        largefiles    track large binary files
        mq            manage a stack of patches
        notify        hooks for sending email push notifications
        pager         browse command output with an external pager
        patchbomb     command to send changesets as (a series of) patch emails
        purge         command to delete untracked files from the working
                      directory
        record        commands to interactively select changes for
                      commit/qrefresh
        relink        recreates hardlinks between repository clones
        schemes       extend schemes with shortcuts to repository swarms
        share         share a common history between several working directories
        shelve        save and restore changes to the working directory
        strip         strip changesets and their descendants from history
        transplant    command to transplant changesets from another branch
        win32mbcs     allow the use of MBCS paths with problematic encodings
        zeroconf      discover and advertise repositories on the local network
 
 Verify that extension keywords appear in help templates
 
   $ hg help --config extensions.transplant= templating|grep transplant > /dev/null
 
 Test short command list with verbose option
 
   $ hg -v help shortlist
   Mercurial Distributed SCM
   
   basic commands:
   
    add           add the specified files on the next commit
    annotate, blame
                  show changeset information by line for each file
    clone         make a copy of an existing repository
    commit, ci    commit the specified files or all outstanding changes
    diff          diff repository (or selected files)
    export        dump the header and diffs for one or more changesets
    forget        forget the specified files on the next commit
    init          create a new repository in the given directory
    log, history  show revision history of entire repository or files
    merge         merge another revision into working directory
    pull          pull changes from the specified source
    push          push changes to the specified destination
    remove, rm    remove the specified files on the next commit
    serve         start stand-alone webserver
    status, st    show changed files in the working directory
    summary, sum  summarize working directory state
    update, up, checkout, co
                  update working directory (or switch revisions)
   
   global options ([+] can be repeated):
   
    -R --repository REPO   repository root directory or name of overlay bundle
                           file
       --cwd DIR           change working directory
    -y --noninteractive    do not prompt, automatically pick the first choice for
                           all prompts
    -q --quiet             suppress output
    -v --verbose           enable additional output
       --config CONFIG [+] set/override config option (use 'section.name=value')
       --debug             enable debugging output
       --debugger          start debugger
       --encoding ENCODE   set the charset encoding (default: ascii)
       --encodingmode MODE set the charset encoding mode (default: strict)
       --traceback         always print a traceback on exception
       --time              time how long the command takes
       --profile           print command execution profile
       --version           output version information and exit
    -h --help              display help and exit
       --hidden            consider hidden changesets
   
   (use "hg help" for the full list of commands)
 
   $ hg add -h
   hg add [OPTION]... [FILE]...
   
   add the specified files on the next commit
   
       Schedule files to be version controlled and added to the repository.
   
       The files will be added to the repository at the next commit. To undo an
       add before that, see "hg forget".
   
       If no names are given, add all files to the repository.
   
       Returns 0 if all files are successfully added.
   
   options ([+] can be repeated):
   
    -I --include PATTERN [+] include names matching the given patterns
    -X --exclude PATTERN [+] exclude names matching the given patterns
    -S --subrepos            recurse into subrepositories
    -n --dry-run             do not perform actions, just print output
   
   (some details hidden, use --verbose to show complete help)
 
 Verbose help for add
 
   $ hg add -hv
   hg add [OPTION]... [FILE]...
   
   add the specified files on the next commit
   
       Schedule files to be version controlled and added to the repository.
   
       The files will be added to the repository at the next commit. To undo an
       add before that, see "hg forget".
   
       If no names are given, add all files to the repository.
   
       An example showing how new (unknown) files are added automatically by "hg
       add":
   
         $ ls
         foo.c
         $ hg status
         ? foo.c
         $ hg add
         adding foo.c
         $ hg status
         A foo.c
   
       Returns 0 if all files are successfully added.
   
   options ([+] can be repeated):
   
    -I --include PATTERN [+] include names matching the given patterns
    -X --exclude PATTERN [+] exclude names matching the given patterns
    -S --subrepos            recurse into subrepositories
    -n --dry-run             do not perform actions, just print output
   
   global options ([+] can be repeated):
   
    -R --repository REPO   repository root directory or name of overlay bundle
                           file
       --cwd DIR           change working directory
    -y --noninteractive    do not prompt, automatically pick the first choice for
                           all prompts
    -q --quiet             suppress output
    -v --verbose           enable additional output
       --config CONFIG [+] set/override config option (use 'section.name=value')
       --debug             enable debugging output
       --debugger          start debugger
       --encoding ENCODE   set the charset encoding (default: ascii)
       --encodingmode MODE set the charset encoding mode (default: strict)
       --traceback         always print a traceback on exception
       --time              time how long the command takes
       --profile           print command execution profile
       --version           output version information and exit
    -h --help              display help and exit
       --hidden            consider hidden changesets
 
 Test help option with version option
 
   $ hg add -h --version
   Mercurial Distributed SCM (version *) (glob)
   (see https://mercurial-scm.org for more information)
   
   Copyright (C) 2005-2015 Matt Mackall and others
   This is free software; see the source for copying conditions. There is NO
   warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 
   $ hg add --skjdfks
   hg add: option --skjdfks not recognized
   hg add [OPTION]... [FILE]...
   
   add the specified files on the next commit
   
   options ([+] can be repeated):
   
    -I --include PATTERN [+] include names matching the given patterns
    -X --exclude PATTERN [+] exclude names matching the given patterns
    -S --subrepos            recurse into subrepositories
    -n --dry-run             do not perform actions, just print output
   
   (use "hg add -h" to show more help)
   [255]
 
 Test ambiguous command help
 
   $ hg help ad
   list of commands:
   
    add           add the specified files on the next commit
    addremove     add all new files, delete all missing files
   
   (use "hg help -v ad" to show built-in aliases and global options)
 
 Test command without options
 
   $ hg help verify
   hg verify
   
   verify the integrity of the repository
   
       Verify the integrity of the current repository.
   
       This will perform an extensive check of the repository's integrity,
       validating the hashes and checksums of each entry in the changelog,
       manifest, and tracked files, as well as the integrity of their crosslinks
       and indices.
   
       Please see https://mercurial-scm.org/wiki/RepositoryCorruption for more
       information about recovery from corruption of the repository.
   
       Returns 0 on success, 1 if errors are encountered.
   
   (some details hidden, use --verbose to show complete help)
 
   $ hg help diff
   hg diff [OPTION]... ([-c REV] | [-r REV1 [-r REV2]]) [FILE]...
   
   diff repository (or selected files)
   
       Show differences between revisions for the specified files.
   
       Differences between files are shown using the unified diff format.
   
       Note:
          diff may generate unexpected results for merges, as it will default to
          comparing against the working directory's first parent changeset if no
          revisions are specified.
   
       When two revision arguments are given, then changes are shown between
       those revisions. If only one revision is specified then that revision is
       compared to the working directory, and, when no revisions are specified,
       the working directory files are compared to its parent.
   
       Alternatively you can specify -c/--change with a revision to see the
       changes in that changeset relative to its first parent.
   
       Without the -a/--text option, diff will avoid generating diffs of files it
       detects as binary. With -a, diff will generate a diff anyway, probably
       with undesirable results.
   
       Use the -g/--git option to generate diffs in the git extended diff format.
       For more information, read "hg help diffs".
   
       Returns 0 on success.
   
   options ([+] can be repeated):
   
    -r --rev REV [+]         revision
    -c --change REV          change made by revision
    -a --text                treat all files as text
    -g --git                 use git extended diff format
       --nodates             omit dates from diff headers
       --noprefix            omit a/ and b/ prefixes from filenames
    -p --show-function       show which function each change is in
       --reverse             produce a diff that undoes the changes
    -w --ignore-all-space    ignore white space when comparing lines
    -b --ignore-space-change ignore changes in the amount of white space
    -B --ignore-blank-lines  ignore changes whose lines are all blank
    -U --unified NUM         number of lines of context to show
       --stat                output diffstat-style summary of changes
       --root DIR            produce diffs relative to subdirectory
    -I --include PATTERN [+] include names matching the given patterns
    -X --exclude PATTERN [+] exclude names matching the given patterns
    -S --subrepos            recurse into subrepositories
   
   (some details hidden, use --verbose to show complete help)
 
   $ hg help status
   hg status [OPTION]... [FILE]...
   
   aliases: st
   
   show changed files in the working directory
   
       Show status of files in the repository. If names are given, only files
       that match are shown. Files that are clean or ignored or the source of a
       copy/move operation, are not listed unless -c/--clean, -i/--ignored,
       -C/--copies or -A/--all are given. Unless options described with "show
       only ..." are given, the options -mardu are used.
   
       Option -q/--quiet hides untracked (unknown and ignored) files unless
       explicitly requested with -u/--unknown or -i/--ignored.
   
       Note:
          status may appear to disagree with diff if permissions have changed or
          a merge has occurred. The standard diff format does not report
          permission changes and diff only reports changes relative to one merge
          parent.
   
       If one revision is given, it is used as the base revision. If two
       revisions are given, the differences between them are shown. The --change
       option can also be used as a shortcut to list the changed files of a
       revision from its first parent.
   
       The codes used to show the status of files are:
   
         M = modified
         A = added
         R = removed
         C = clean
         ! = missing (deleted by non-hg command, but still tracked)
         ? = not tracked
         I = ignored
           = origin of the previous file (with --copies)
   
       Returns 0 on success.
   
   options ([+] can be repeated):
   
    -A --all                 show status of all files
    -m --modified            show only modified files
    -a --added               show only added files
    -r --removed             show only removed files
    -d --deleted             show only deleted (but tracked) files
    -c --clean               show only files without changes
    -u --unknown             show only unknown (not tracked) files
    -i --ignored             show only ignored files
    -n --no-status           hide status prefix
    -C --copies              show source of copied files
    -0 --print0              end filenames with NUL, for use with xargs
       --rev REV [+]         show difference from revision
       --change REV          list the changed files of a revision
    -I --include PATTERN [+] include names matching the given patterns
    -X --exclude PATTERN [+] exclude names matching the given patterns
    -S --subrepos            recurse into subrepositories
   
   (some details hidden, use --verbose to show complete help)
 
   $ hg -q help status
   hg status [OPTION]... [FILE]...
   
   show changed files in the working directory
 
   $ hg help foo
   abort: no such help topic: foo
   (try "hg help --keyword foo")
   [255]
 
   $ hg skjdfks
   hg: unknown command 'skjdfks'
   Mercurial Distributed SCM
   
   basic commands:
   
    add           add the specified files on the next commit
    annotate      show changeset information by line for each file
    clone         make a copy of an existing repository
    commit        commit the specified files or all outstanding changes
    diff          diff repository (or selected files)
    export        dump the header and diffs for one or more changesets
    forget        forget the specified files on the next commit
    init          create a new repository in the given directory
    log           show revision history of entire repository or files
    merge         merge another revision into working directory
    pull          pull changes from the specified source
    push          push changes to the specified destination
    remove        remove the specified files on the next commit
    serve         start stand-alone webserver
    status        show changed files in the working directory
    summary       summarize working directory state
    update        update working directory (or switch revisions)
   
   (use "hg help" for the full list of commands or "hg -v" for details)
   [255]
 
 
 Make sure that we don't run afoul of the help system thinking that
 this is a section and erroring out weirdly.
 
   $ hg .log
   hg: unknown command '.log'
   (did you mean one of log?)
   [255]
 
   $ hg log.
   hg: unknown command 'log.'
   (did you mean one of log?)
   [255]
   $ hg pu.lh
   hg: unknown command 'pu.lh'
   (did you mean one of pull, push?)
   [255]
 
   $ cat > helpext.py <<EOF
   > import os
   > from mercurial import cmdutil, commands
   > 
   > cmdtable = {}
   > command = cmdutil.command(cmdtable)
   > 
   > @command('nohelp',
   >     [('', 'longdesc', 3, 'x'*90),
   >     ('n', '', None, 'normal desc'),
   >     ('', 'newline', '', 'line1\nline2')],
   >     'hg nohelp',
   >     norepo=True)
   > @command('debugoptDEP', [('', 'dopt', None, 'option is (DEPRECATED)')])
   > @command('debugoptEXP', [('', 'eopt', None, 'option is (EXPERIMENTAL)')])
   > def nohelp(ui, *args, **kwargs):
   >     pass
   > 
   > EOF
   $ echo '[extensions]' >> $HGRCPATH
   $ echo "helpext = `pwd`/helpext.py" >> $HGRCPATH
 
 Test command with no help text
 
   $ hg help nohelp
   hg nohelp
   
   (no help text available)
   
   options:
   
       --longdesc VALUE xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
                        xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx (default: 3)
    -n --               normal desc
       --newline VALUE  line1 line2
   
   (some details hidden, use --verbose to show complete help)
 
   $ hg help -k nohelp
   Commands:
   
    nohelp hg nohelp
   
   Extension Commands:
   
    nohelp (no help text available)
 
 Test that default list of commands omits extension commands
 
   $ hg help
   Mercurial Distributed SCM
   
   list of commands:
   
    add           add the specified files on the next commit
    addremove     add all new files, delete all missing files
    annotate      show changeset information by line for each file
    archive       create an unversioned archive of a repository revision
    backout       reverse effect of earlier changeset
    bisect        subdivision search of changesets
    bookmarks     create a new bookmark or list existing bookmarks
    branch        set or show the current branch name
    branches      list repository named branches
    bundle        create a changegroup file
    cat           output the current or given revision of files
    clone         make a copy of an existing repository
    commit        commit the specified files or all outstanding changes
    config        show combined config settings from all hgrc files
    copy          mark files as copied for the next commit
    diff          diff repository (or selected files)
    export        dump the header and diffs for one or more changesets
    files         list tracked files
    forget        forget the specified files on the next commit
    graft         copy changes from other branches onto the current branch
    grep          search for a pattern in specified files and revisions
    heads         show branch heads
    help          show help for a given topic or a help overview
    identify      identify the working directory or specified revision
    import        import an ordered set of patches
    incoming      show new changesets found in source
    init          create a new repository in the given directory
    log           show revision history of entire repository or files
    manifest      output the current or given revision of the project manifest
    merge         merge another revision into working directory
    outgoing      show changesets not found in the destination
    paths         show aliases for remote repositories
    phase         set or show the current phase name
    pull          pull changes from the specified source
    push          push changes to the specified destination
    recover       roll back an interrupted transaction
    remove        remove the specified files on the next commit
    rename        rename files; equivalent of copy + remove
    resolve       redo merges or set/view the merge status of files
    revert        restore files to their checkout state
    root          print the root (top) of the current working directory
    serve         start stand-alone webserver
    status        show changed files in the working directory
    summary       summarize working directory state
    tag           add one or more tags for the current or given revision
    tags          list repository tags
    unbundle      apply one or more changegroup files
    update        update working directory (or switch revisions)
    verify        verify the integrity of the repository
    version       output version and copyright information
   
   enabled extensions:
   
    helpext       (no help text available)
   
   additional help topics:
   
    config        Configuration Files
    dates         Date Formats
    diffs         Diff Formats
    environment   Environment Variables
    extensions    Using Additional Features
    filesets      Specifying File Sets
    glossary      Glossary
    hgignore      Syntax for Mercurial Ignore Files
    hgweb         Configuring hgweb
    merge-tools   Merge Tools
    multirevs     Specifying Multiple Revisions
    patterns      File Name Patterns
    phases        Working with Phases
    revisions     Specifying Single Revisions
    revsets       Specifying Revision Sets
    scripting     Using Mercurial from scripts and automation
    subrepos      Subrepositories
    templating    Template Usage
    urls          URL Paths
   
   (use "hg help -v" to show built-in aliases and global options)
 
 
 Test list of internal help commands
 
   $ hg help debug
   debug commands (internal and unsupported):
   
    debugancestor
                  find the ancestor revision of two revisions in a given index
    debugbuilddag
                  builds a repo with a given DAG from scratch in the current
                  empty repo
    debugbundle   lists the contents of a bundle
    debugcheckstate
                  validate the correctness of the current dirstate
    debugcommands
                  list all available commands and options
    debugcomplete
                  returns the completion list associated with the given command
    debugdag      format the changelog or an index DAG as a concise textual
                  description
    debugdata     dump the contents of a data file revision
    debugdate     parse and display a date
    debugdirstate
                  show the contents of the current dirstate
    debugdiscovery
                  runs the changeset discovery protocol in isolation
    debugextensions
                  show information about active extensions
    debugfileset  parse and apply a fileset specification
    debugfsinfo   show information detected about current filesystem
    debuggetbundle
                  retrieves a bundle from a repo
    debugignore   display the combined ignore pattern
    debugindex    dump the contents of an index file
    debugindexdot
                  dump an index DAG as a graphviz dot file
    debuginstall  test Mercurial installation
    debugknown    test whether node ids are known to a repo
    debuglocks    show or modify state of locks
    debugmergestate
                  print merge state
    debugnamecomplete
                  complete "names" - tags, open branch names, bookmark names
    debugobsolete
                  create arbitrary obsolete marker
    debugoptDEP   (no help text available)
    debugoptEXP   (no help text available)
    debugpathcomplete
                  complete part or all of a tracked path
    debugpushkey  access the pushkey key/value protocol
    debugpvec     (no help text available)
    debugrebuilddirstate
                  rebuild the dirstate as it would look like for the given
                  revision
    debugrebuildfncache
                  rebuild the fncache file
    debugrename   dump rename information
    debugrevlog   show data and statistics about a revlog
    debugrevspec  parse and apply a revision specification
    debugsetparents
                  manually set the parents of the current working directory
    debugsub      (no help text available)
    debugsuccessorssets
                  show set of successors for revision
    debugwalk     show how files match on given patterns
    debugwireargs
                  (no help text available)
   
   (use "hg help -v debug" to show built-in aliases and global options)
 
 
 Test list of commands with command with no help text
 
   $ hg help helpext
   helpext extension - no help text available
   
   list of commands:
   
    nohelp        (no help text available)
   
   (use "hg help -v helpext" to show built-in aliases and global options)
 
 
 test deprecated and experimental options are hidden in command help
   $ hg help debugoptDEP
   hg debugoptDEP
   
   (no help text available)
   
   options:
   
   (some details hidden, use --verbose to show complete help)
 
   $ hg help debugoptEXP
   hg debugoptEXP
   
   (no help text available)
   
   options:
   
   (some details hidden, use --verbose to show complete help)
 
 test deprecated and experimental options is shown with -v
   $ hg help -v debugoptDEP | grep dopt
     --dopt option is (DEPRECATED)
   $ hg help -v debugoptEXP | grep eopt
     --eopt option is (EXPERIMENTAL)
 
 #if gettext
 test deprecated option is hidden with translation with untranslated description
 (use many globy for not failing on changed transaction)
   $ LANGUAGE=sv hg help debugoptDEP
   hg debugoptDEP
   
   (*) (glob)
   
   options:
   
   (some details hidden, use --verbose to show complete help)
 #endif
 
 Test commands that collide with topics (issue4240)
 
   $ hg config -hq
   hg config [-u] [NAME]...
   
   show combined config settings from all hgrc files
   $ hg showconfig -hq
   hg config [-u] [NAME]...
   
   show combined config settings from all hgrc files
 
 Test a help topic
 
   $ hg help revs
   Specifying Single Revisions
   """""""""""""""""""""""""""
   
       Mercurial supports several ways to specify individual revisions.
   
       A plain integer is treated as a revision number. Negative integers are
       treated as sequential offsets from the tip, with -1 denoting the tip, -2
       denoting the revision prior to the tip, and so forth.
   
       A 40-digit hexadecimal string is treated as a unique revision identifier.
   
       A hexadecimal string less than 40 characters long is treated as a unique
       revision identifier and is referred to as a short-form identifier. A
       short-form identifier is only valid if it is the prefix of exactly one
       full-length identifier.
   
       Any other string is treated as a bookmark, tag, or branch name. A bookmark
       is a movable pointer to a revision. A tag is a permanent name associated
       with a revision. A branch name denotes the tipmost open branch head of
       that branch - or if they are all closed, the tipmost closed head of the
       branch. Bookmark, tag, and branch names must not contain the ":"
       character.
   
       The reserved name "tip" always identifies the most recent revision.
   
       The reserved name "null" indicates the null revision. This is the revision
       of an empty repository, and the parent of revision 0.
   
       The reserved name "." indicates the working directory parent. If no
       working directory is checked out, it is equivalent to null. If an
       uncommitted merge is in progress, "." is the revision of the first parent.
 
 Test repeated config section name
 
   $ hg help config.host
       "http_proxy.host"
           Host name and (optional) port of the proxy server, for example
           "myproxy:8000".
   
       "smtp.host"
           Host name of mail server, e.g. "mail.example.com".
   
 Unrelated trailing paragraphs shouldn't be included
 
   $ hg help config.extramsg | grep '^$'
   
 
 Test capitalized section name
 
   $ hg help scripting.HGPLAIN > /dev/null
 
 Help subsection:
 
   $ hg help config.charsets |grep "Email example:" > /dev/null
   [1]
 
 Show nested definitions
 ("profiling.type"[break]"ls"[break]"stat"[break])
 
   $ hg help config.type | egrep '^$'|wc -l
   \s*3 (re)
 
 Last item in help config.*:
 
   $ hg help config.`hg help config|grep '^    "'| \
   >       tail -1|sed 's![ "]*!!g'`| \
   >   grep "hg help -c config" > /dev/null
   [1]
 
 note to use help -c for general hg help config:
 
   $ hg help config |grep "hg help -c config" > /dev/null
 
 Test templating help
 
   $ hg help templating | egrep '(desc|diffstat|firstline|nonempty)  '
       desc          String. The text of the changeset description.
       diffstat      String. Statistics of changes with the following format:
       firstline     Any text. Returns the first line of text.
       nonempty      Any text. Returns '(none)' if the string is empty.
 
 Test deprecated items
 
   $ hg help -v templating | grep currentbookmark
       currentbookmark
   $ hg help templating | (grep currentbookmark || true)
 
 Test help hooks
 
   $ cat > helphook1.py <<EOF
   > from mercurial import help
   > 
   > def rewrite(ui, topic, doc):
   >     return doc + '\nhelphook1\n'
   > 
   > def extsetup(ui):
   >     help.addtopichook('revsets', rewrite)
   > EOF
   $ cat > helphook2.py <<EOF
   > from mercurial import help
   > 
   > def rewrite(ui, topic, doc):
   >     return doc + '\nhelphook2\n'
   > 
   > def extsetup(ui):
   >     help.addtopichook('revsets', rewrite)
   > EOF
   $ echo '[extensions]' >> $HGRCPATH
   $ echo "helphook1 = `pwd`/helphook1.py" >> $HGRCPATH
   $ echo "helphook2 = `pwd`/helphook2.py" >> $HGRCPATH
   $ hg help revsets | grep helphook
       helphook1
       helphook2
 
 Test -e / -c / -k combinations
 
   $ hg help -c progress
   abort: no such help topic: progress
   (try "hg help --keyword progress")
   [255]
   $ hg help -e progress |head -1
   progress extension - show progress bars for some actions (DEPRECATED)
   $ hg help -c -k dates |egrep '^(Topics|Extensions|Commands):'
   Commands:
   $ hg help -e -k a |egrep '^(Topics|Extensions|Commands):'
   Extensions:
   $ hg help -e -c -k date |egrep '^(Topics|Extensions|Commands):'
   Extensions:
   Commands:
   $ hg help -c commit > /dev/null
   $ hg help -e -c commit > /dev/null
   $ hg help -e commit > /dev/null
   abort: no such help topic: commit
   (try "hg help --keyword commit")
   [255]
 
 Test keyword search help
 
   $ cat > prefixedname.py <<EOF
   > '''matched against word "clone"
   > '''
   > EOF
   $ echo '[extensions]' >> $HGRCPATH
   $ echo "dot.dot.prefixedname = `pwd`/prefixedname.py" >> $HGRCPATH
   $ hg help -k clone
   Topics:
   
    config     Configuration Files
    extensions Using Additional Features
    glossary   Glossary
    phases     Working with Phases
    subrepos   Subrepositories
    urls       URL Paths
   
   Commands:
   
    bookmarks create a new bookmark or list existing bookmarks
    clone     make a copy of an existing repository
    paths     show aliases for remote repositories
    update    update working directory (or switch revisions)
   
   Extensions:
   
+   clonebundles server side extension to advertise pre-generated bundles to seed
+                clones.
    prefixedname matched against word "clone"
    relink       recreates hardlinks between repository clones
   
   Extension Commands:
   
    qclone clone main and patch repository at same time
 
 Test unfound topic
 
   $ hg help nonexistingtopicthatwillneverexisteverever
   abort: no such help topic: nonexistingtopicthatwillneverexisteverever
   (try "hg help --keyword nonexistingtopicthatwillneverexisteverever")
   [255]
 
 Test unfound keyword
 
   $ hg help --keyword nonexistingwordthatwillneverexisteverever
   abort: no matches
   (try "hg help" for a list of topics)
   [255]
 
 Test omit indicating for help
 
   $ cat > addverboseitems.py <<EOF
   > '''extension to test omit indicating.
   > 
   > This paragraph is never omitted (for extension)
   > 
   > .. container:: verbose
   > 
   >   This paragraph is omitted,
   >   if :hg:\`help\` is invoked without \`\`-v\`\` (for extension)
   > 
   > This paragraph is never omitted, too (for extension)
   > '''
   > 
   > from mercurial import help, commands
   > testtopic = """This paragraph is never omitted (for topic).
   > 
   > .. container:: verbose
   > 
   >   This paragraph is omitted,
   >   if :hg:\`help\` is invoked without \`\`-v\`\` (for topic)
   > 
   > This paragraph is never omitted, too (for topic)
   > """
   > def extsetup(ui):
   >     help.helptable.append((["topic-containing-verbose"],
   >                            "This is the topic to test omit indicating.",
   >                            lambda ui: testtopic))
   > EOF
   $ echo '[extensions]' >> $HGRCPATH
   $ echo "addverboseitems = `pwd`/addverboseitems.py" >> $HGRCPATH
   $ hg help addverboseitems
   addverboseitems extension - extension to test omit indicating.
   
   This paragraph is never omitted (for extension)
   
   This paragraph is never omitted, too (for extension)
   
   (some details hidden, use --verbose to show complete help)
   
   no commands defined
   $ hg help -v addverboseitems
   addverboseitems extension - extension to test omit indicating.
   
   This paragraph is never omitted (for extension)
   
   This paragraph is omitted, if "hg help" is invoked without "-v" (for
   extension)
   
   This paragraph is never omitted, too (for extension)
   
   no commands defined
   $ hg help topic-containing-verbose
   This is the topic to test omit indicating.
   """"""""""""""""""""""""""""""""""""""""""
   
       This paragraph is never omitted (for topic).
   
       This paragraph is never omitted, too (for topic)
   
   (some details hidden, use --verbose to show complete help)
   $ hg help -v topic-containing-verbose
   This is the topic to test omit indicating.
   """"""""""""""""""""""""""""""""""""""""""
   
       This paragraph is never omitted (for topic).
   
       This paragraph is omitted, if "hg help" is invoked without "-v" (for
       topic)
   
       This paragraph is never omitted, too (for topic)
 
 Test section lookup
 
   $ hg help revset.merge
       "merge()"
         Changeset is a merge changeset.
   
   $ hg help glossary.dag
       DAG
           The repository of changesets of a distributed version control system
           (DVCS) can be described as a directed acyclic graph (DAG), consisting
           of nodes and edges, where nodes correspond to changesets and edges
           imply a parent -> child relation. This graph can be visualized by
           graphical tools such as "hg log --graph". In Mercurial, the DAG is
           limited by the requirement for children to have at most two parents.
   
 
   $ hg help hgrc.paths
       "paths"
       -------
   
       Assigns symbolic names to repositories. The left side is the symbolic
       name, and the right gives the directory or URL that is the location of the
       repository. Default paths can be declared by setting the following
       entries.
   
       "default"
           Directory or URL to use when pulling if no source is specified.
           (default: repository from which the current repository was cloned)
   
       "default-push"
           Optional. Directory or URL to use when pushing if no destination is
           specified.
   
       Custom paths can be defined by assigning the path to a name that later can
       be used from the command line. Example:
   
         [paths]
         my_path = http://example.com/path
   
       To push to the path defined in "my_path" run the command:
   
         hg push my_path
   
   $ hg help glossary.mcguffin
   abort: help section not found
   [255]
 
   $ hg help glossary.mc.guffin
   abort: help section not found
   [255]
 
   $ hg help template.files
       files         List of strings. All files modified, added, or removed by
                     this changeset.
 
 Test dynamic list of merge tools only shows up once
   $ hg help merge-tools
   Merge Tools
   """""""""""
   
       To merge files Mercurial uses merge tools.
   
       A merge tool combines two different versions of a file into a merged file.
       Merge tools are given the two files and the greatest common ancestor of
       the two file versions, so they can determine the changes made on both
       branches.
   
       Merge tools are used both for "hg resolve", "hg merge", "hg update", "hg
       backout" and in several extensions.
   
       Usually, the merge tool tries to automatically reconcile the files by
       combining all non-overlapping changes that occurred separately in the two
       different evolutions of the same initial base file. Furthermore, some
       interactive merge programs make it easier to manually resolve conflicting
       merges, either in a graphical way, or by inserting some conflict markers.
       Mercurial does not include any interactive merge programs but relies on
       external tools for that.
   
       Available merge tools
       =====================
   
       External merge tools and their properties are configured in the merge-
       tools configuration section - see hgrc(5) - but they can often just be
       named by their executable.
   
       A merge tool is generally usable if its executable can be found on the
       system and if it can handle the merge. The executable is found if it is an
       absolute or relative executable path or the name of an application in the
       executable search path. The tool is assumed to be able to handle the merge
       if it can handle symlinks if the file is a symlink, if it can handle
       binary files if the file is binary, and if a GUI is available if the tool
       requires a GUI.
   
       There are some internal merge tools which can be used. The internal merge
       tools are:
   
       ":dump"
         Creates three versions of the files to merge, containing the contents of
         local, other and base. These files can then be used to perform a merge
         manually. If the file to be merged is named "a.txt", these files will
         accordingly be named "a.txt.local", "a.txt.other" and "a.txt.base" and
         they will be placed in the same directory as "a.txt".
   
       ":fail"
         Rather than attempting to merge files that were modified on both
         branches, it marks them as unresolved. The resolve command must be used
         to resolve these conflicts.
   
       ":local"
         Uses the local version of files as the merged version.
   
       ":merge"
         Uses the internal non-interactive simple merge algorithm for merging
         files. It will fail if there are any conflicts and leave markers in the
         partially merged file. Markers will have two sections, one for each side
         of merge.
   
       ":merge-local"
         Like :merge, but resolve all conflicts non-interactively in favor of the
         local changes.
   
       ":merge-other"
         Like :merge, but resolve all conflicts non-interactively in favor of the
         other changes.
   
       ":merge3"
         Uses the internal non-interactive simple merge algorithm for merging
         files. It will fail if there are any conflicts and leave markers in the
         partially merged file. Marker will have three sections, one from each
         side of the merge and one for the base content.
   
       ":other"
         Uses the other version of files as the merged version.
   
       ":prompt"
         Asks the user which of the local or the other version to keep as the
         merged version.
   
       ":tagmerge"
         Uses the internal tag merge algorithm (experimental).
   
       ":union"
         Uses the internal non-interactive simple merge algorithm for merging
         files. It will use both left and right sides for conflict regions. No
         markers are inserted.
   
       Internal tools are always available and do not require a GUI but will by
       default not handle symlinks or binary files.
   
       Choosing a merge tool
       =====================
   
       Mercurial uses these rules when deciding which merge tool to use:
   
       1. If a tool has been specified with the --tool option to merge or
          resolve, it is used.  If it is the name of a tool in the merge-tools
          configuration, its configuration is used. Otherwise the specified tool
          must be executable by the shell.
       2. If the "HGMERGE" environment variable is present, its value is used and
          must be executable by the shell.
       3. If the filename of the file to be merged matches any of the patterns in
          the merge-patterns configuration section, the first usable merge tool
          corresponding to a matching pattern is used. Here, binary capabilities
          of the merge tool are not considered.
       4. If ui.merge is set it will be considered next. If the value is not the
          name of a configured tool, the specified value is used and must be
          executable by the shell. Otherwise the named tool is used if it is
          usable.
       5. If any usable merge tools are present in the merge-tools configuration
          section, the one with the highest priority is used.
       6. If a program named "hgmerge" can be found on the system, it is used -
          but it will by default not be used for symlinks and binary files.
       7. If the file to be merged is not binary and is not a symlink, then
          internal ":merge" is used.
       8. The merge of the file fails and must be resolved before commit.
   
       Note:
          After selecting a merge program, Mercurial will by default attempt to
          merge the files using a simple merge algorithm first. Only if it
          doesn't succeed because of conflicting changes Mercurial will actually
          execute the merge program. Whether to use the simple merge algorithm
          first can be controlled by the premerge setting of the merge tool.
          Premerge is enabled by default unless the file is binary or a symlink.
   
       See the merge-tools and ui sections of hgrc(5) for details on the
       configuration of merge tools.
 
 Test usage of section marks in help documents
 
   $ cd "$TESTDIR"/../doc
   $ python check-seclevel.py
   $ cd $TESTTMP
 
 #if serve
 
 Test the help pages in hgweb.
 
 Dish up an empty repo; serve it cold.
 
   $ hg init "$TESTTMP/test"
   $ hg serve -R "$TESTTMP/test" -n test -p $HGPORT -d --pid-file=hg.pid
   $ cat hg.pid >> $DAEMON_PIDS
 
   $ get-with-headers.py 127.0.0.1:$HGPORT "help"
   200 Script output follows
   
   <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
   <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-US">
   <head>
   <link rel="icon" href="/static/hgicon.png" type="image/png" />
   <meta name="robots" content="index, nofollow" />
   <link rel="stylesheet" href="/static/style-paper.css" type="text/css" />
   <script type="text/javascript" src="/static/mercurial.js"></script>
   
   <title>Help: Index</title>
   </head>
   <body>
   
   <div class="container">
   <div class="menu">
   <div class="logo">
   <a href="https://mercurial-scm.org/">
   <img src="/static/hglogo.png" alt="mercurial" /></a>
   </div>
   <ul>
   <li><a href="/shortlog">log</a></li>
   <li><a href="/graph">graph</a></li>
   <li><a href="/tags">tags</a></li>
   <li><a href="/bookmarks">bookmarks</a></li>
   <li><a href="/branches">branches</a></li>
   </ul>
   <ul>
   <li class="active">help</li>
   </ul>
   </div>
   
   <div class="main">
   <h2 class="breadcrumb"><a href="/">Mercurial</a> </h2>
   <form class="search" action="/log">
   
   <p><input name="rev" id="search1" type="text" size="30" /></p>
   <div id="hint">Find changesets by keywords (author, files, the commit message), revision
   number or hash, or <a href="/help/revsets">revset expression</a>.</div>
   </form>
   <table class="bigtable">
   <tr><td colspan="2"><h2><a name="main" href="#topics">Topics</a></h2></td></tr>
   
   <tr><td>
   <a href="/help/config">
   config
   </a>
   </td><td>
   Configuration Files
   </td></tr>
   <tr><td>
   <a href="/help/dates">
   dates
   </a>
   </td><td>
   Date Formats
   </td></tr>
   <tr><td>
   <a href="/help/diffs">
   diffs
   </a>
   </td><td>
   Diff Formats
   </td></tr>
   <tr><td>
   <a href="/help/environment">
   environment
   </a>
   </td><td>
   Environment Variables
   </td></tr>
   <tr><td>
   <a href="/help/extensions">
   extensions
   </a>
   </td><td>
   Using Additional Features
   </td></tr>
   <tr><td>
   <a href="/help/filesets">
   filesets
   </a>
   </td><td>
   Specifying File Sets
   </td></tr>
   <tr><td>
   <a href="/help/glossary">
   glossary
   </a>
   </td><td>
   Glossary
   </td></tr>
   <tr><td>
   <a href="/help/hgignore">
   hgignore
   </a>
   </td><td>
   Syntax for Mercurial Ignore Files
   </td></tr>
   <tr><td>
   <a href="/help/hgweb">
   hgweb
   </a>
   </td><td>
   Configuring hgweb
   </td></tr>
   <tr><td>
   <a href="/help/merge-tools">
   merge-tools
   </a>
   </td><td>
   Merge Tools
   </td></tr>
   <tr><td>
   <a href="/help/multirevs">
   multirevs
   </a>
   </td><td>
   Specifying Multiple Revisions
   </td></tr>
   <tr><td>
   <a href="/help/patterns">
   patterns
   </a>
   </td><td>
   File Name Patterns
   </td></tr>
   <tr><td>
   <a href="/help/phases">
   phases
   </a>
   </td><td>
   Working with Phases
   </td></tr>
   <tr><td>
   <a href="/help/revisions">
   revisions
   </a>
   </td><td>
   Specifying Single Revisions
   </td></tr>
   <tr><td>
   <a href="/help/revsets">
   revsets
   </a>
   </td><td>
   Specifying Revision Sets
   </td></tr>
   <tr><td>
   <a href="/help/scripting">
   scripting
   </a>
   </td><td>
   Using Mercurial from scripts and automation
   </td></tr>
   <tr><td>
   <a href="/help/subrepos">
   subrepos
   </a>
   </td><td>
   Subrepositories
   </td></tr>
   <tr><td>
   <a href="/help/templating">
   templating
   </a>
   </td><td>
   Template Usage
   </td></tr>
   <tr><td>
   <a href="/help/urls">
   urls
   </a>
   </td><td>
   URL Paths
   </td></tr>
   <tr><td>
   <a href="/help/topic-containing-verbose">
   topic-containing-verbose
   </a>
   </td><td>
   This is the topic to test omit indicating.
   </td></tr>
   
   <tr><td colspan="2"><h2><a name="main" href="#main">Main Commands</a></h2></td></tr>
   
   <tr><td>
   <a href="/help/add">
   add
   </a>
   </td><td>
   add the specified files on the next commit
   </td></tr>
   <tr><td>
   <a href="/help/annotate">
   annotate
   </a>
   </td><td>
   show changeset information by line for each file
   </td></tr>
   <tr><td>
   <a href="/help/clone">
   clone
   </a>
   </td><td>
   make a copy of an existing repository
   </td></tr>
   <tr><td>
   <a href="/help/commit">
   commit
   </a>
   </td><td>
   commit the specified files or all outstanding changes
   </td></tr>
   <tr><td>
   <a href="/help/diff">
   diff
   </a>
   </td><td>
   diff repository (or selected files)
   </td></tr>
   <tr><td>
   <a href="/help/export">
   export
   </a>
   </td><td>
   dump the header and diffs for one or more changesets
   </td></tr>
   <tr><td>
   <a href="/help/forget">
   forget
   </a>
   </td><td>
   forget the specified files on the next commit
   </td></tr>
   <tr><td>
   <a href="/help/init">
   init
   </a>
   </td><td>
   create a new repository in the given directory
   </td></tr>
   <tr><td>
   <a href="/help/log">
   log
   </a>
   </td><td>
   show revision history of entire repository or files
   </td></tr>
   <tr><td>
   <a href="/help/merge">
   merge
   </a>
   </td><td>
   merge another revision into working directory
   </td></tr>
   <tr><td>
   <a href="/help/pull">
   pull
   </a>
   </td><td>
   pull changes from the specified source
   </td></tr>
   <tr><td>
   <a href="/help/push">
   push
   </a>
   </td><td>
   push changes to the specified destination
   </td></tr>
   <tr><td>
   <a href="/help/remove">
   remove
   </a>
   </td><td>
   remove the specified files on the next commit
   </td></tr>
   <tr><td>
   <a href="/help/serve">
   serve
   </a>
   </td><td>
   start stand-alone webserver
   </td></tr>
   <tr><td>
   <a href="/help/status">
   status
   </a>
   </td><td>
   show changed files in the working directory
   </td></tr>
   <tr><td>
   <a href="/help/summary">
   summary
   </a>
   </td><td>
   summarize working directory state
   </td></tr>
   <tr><td>
   <a href="/help/update">
   update
   </a>
   </td><td>
   update working directory (or switch revisions)
   </td></tr>
   
   <tr><td colspan="2"><h2><a name="other" href="#other">Other Commands</a></h2></td></tr>
   
   <tr><td>
   <a href="/help/addremove">
   addremove
   </a>
   </td><td>
   add all new files, delete all missing files
   </td></tr>
   <tr><td>
   <a href="/help/archive">
   archive
   </a>
   </td><td>
   create an unversioned archive of a repository revision
   </td></tr>
   <tr><td>
   <a href="/help/backout">
   backout
   </a>
   </td><td>
   reverse effect of earlier changeset
   </td></tr>
   <tr><td>
   <a href="/help/bisect">
   bisect
   </a>
   </td><td>
   subdivision search of changesets
   </td></tr>
   <tr><td>
   <a href="/help/bookmarks">
   bookmarks
   </a>
   </td><td>
   create a new bookmark or list existing bookmarks
   </td></tr>
   <tr><td>
   <a href="/help/branch">
   branch
   </a>
   </td><td>
   set or show the current branch name
   </td></tr>
   <tr><td>
   <a href="/help/branches">
   branches
   </a>
   </td><td>
   list repository named branches
   </td></tr>
   <tr><td>
   <a href="/help/bundle">
   bundle
   </a>
   </td><td>
   create a changegroup file
   </td></tr>
   <tr><td>
   <a href="/help/cat">
   cat
   </a>
   </td><td>
   output the current or given revision of files
   </td></tr>
   <tr><td>
   <a href="/help/config">
   config
   </a>
   </td><td>
   show combined config settings from all hgrc files
   </td></tr>
   <tr><td>
   <a href="/help/copy">
   copy
   </a>
   </td><td>
   mark files as copied for the next commit
   </td></tr>
   <tr><td>
   <a href="/help/files">
   files
   </a>
   </td><td>
   list tracked files
   </td></tr>
   <tr><td>
   <a href="/help/graft">
   graft
   </a>
   </td><td>
   copy changes from other branches onto the current branch
   </td></tr>
   <tr><td>
   <a href="/help/grep">
   grep
   </a>
   </td><td>
   search for a pattern in specified files and revisions
   </td></tr>
   <tr><td>
   <a href="/help/heads">
   heads
   </a>
   </td><td>
   show branch heads
   </td></tr>
   <tr><td>
   <a href="/help/help">
   help
   </a>
   </td><td>
   show help for a given topic or a help overview
   </td></tr>
   <tr><td>
   <a href="/help/identify">
   identify
   </a>
   </td><td>
   identify the working directory or specified revision
   </td></tr>
   <tr><td>
   <a href="/help/import">
   import
   </a>
   </td><td>
   import an ordered set of patches
   </td></tr>
   <tr><td>
   <a href="/help/incoming">
   incoming
   </a>
   </td><td>
   show new changesets found in source
   </td></tr>
   <tr><td>
   <a href="/help/manifest">
   manifest
   </a>
   </td><td>
   output the current or given revision of the project manifest
   </td></tr>
   <tr><td>
   <a href="/help/nohelp">
   nohelp
   </a>
   </td><td>
   (no help text available)
   </td></tr>
   <tr><td>
   <a href="/help/outgoing">
   outgoing
   </a>
   </td><td>
   show changesets not found in the destination
   </td></tr>
   <tr><td>
   <a href="/help/paths">
   paths
   </a>
   </td><td>
   show aliases for remote repositories
   </td></tr>
   <tr><td>
   <a href="/help/phase">
   phase
   </a>
   </td><td>
   set or show the current phase name
   </td></tr>
   <tr><td>
   <a href="/help/recover">
   recover
   </a>
   </td><td>
   roll back an interrupted transaction
   </td></tr>
   <tr><td>
   <a href="/help/rename">
   rename
   </a>
   </td><td>
   rename files; equivalent of copy + remove
   </td></tr>
   <tr><td>
   <a href="/help/resolve">
   resolve
   </a>
   </td><td>
   redo merges or set/view the merge status of files
   </td></tr>
   <tr><td>
   <a href="/help/revert">
   revert
   </a>
   </td><td>
   restore files to their checkout state
   </td></tr>
   <tr><td>
   <a href="/help/root">
   root
   </a>
   </td><td>
   print the root (top) of the current working directory
   </td></tr>
   <tr><td>
   <a href="/help/tag">
   tag
   </a>
   </td><td>
   add one or more tags for the current or given revision
   </td></tr>
   <tr><td>
   <a href="/help/tags">
   tags
   </a>
   </td><td>
   list repository tags
   </td></tr>
   <tr><td>
   <a href="/help/unbundle">
   unbundle
   </a>
   </td><td>
   apply one or more changegroup files
   </td></tr>
   <tr><td>
   <a href="/help/verify">
   verify
   </a>
   </td><td>
   verify the integrity of the repository
   </td></tr>
   <tr><td>
   <a href="/help/version">
   version
   </a>
   </td><td>
   output version and copyright information
   </td></tr>
   </table>
   </div>
   </div>
   
   <script type="text/javascript">process_dates()</script>
   
   
   </body>
   </html>
   
 
   $ get-with-headers.py 127.0.0.1:$HGPORT "help/add"
   200 Script output follows
   
   <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
   <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-US">
   <head>
   <link rel="icon" href="/static/hgicon.png" type="image/png" />
   <meta name="robots" content="index, nofollow" />
   <link rel="stylesheet" href="/static/style-paper.css" type="text/css" />
   <script type="text/javascript" src="/static/mercurial.js"></script>
   
   <title>Help: add</title>
   </head>
   <body>
   
   <div class="container">
   <div class="menu">
   <div class="logo">
   <a href="https://mercurial-scm.org/">
   <img src="/static/hglogo.png" alt="mercurial" /></a>
   </div>
   <ul>
   <li><a href="/shortlog">log</a></li>
   <li><a href="/graph">graph</a></li>
   <li><a href="/tags">tags</a></li>
   <li><a href="/bookmarks">bookmarks</a></li>
   <li><a href="/branches">branches</a></li>
   </ul>
   <ul>
    <li class="active"><a href="/help">help</a></li>
   </ul>
   </div>
   
   <div class="main">
   <h2 class="breadcrumb"><a href="/">Mercurial</a> </h2>
   <h3>Help: add</h3>
   
   <form class="search" action="/log">
   
   <p><input name="rev" id="search1" type="text" size="30" /></p>
   <div id="hint">Find changesets by keywords (author, files, the commit message), revision
   number or hash, or <a href="/help/revsets">revset expression</a>.</div>
   </form>
   <div id="doc">
   <p>
   hg add [OPTION]... [FILE]...
   </p>
   <p>
   add the specified files on the next commit
   </p>
   <p>
   Schedule files to be version controlled and added to the
   repository.
   </p>
   <p>
   The files will be added to the repository at the next commit. To
   undo an add before that, see &quot;hg forget&quot;.
   </p>
   <p>
   If no names are given, add all files to the repository.
   </p>
   <p>
   An example showing how new (unknown) files are added
   automatically by &quot;hg add&quot;:
   </p>
   <pre>
   \$ ls (re)
   foo.c
   \$ hg status (re)
   ? foo.c
   \$ hg add (re)
   adding foo.c
   \$ hg status (re)
   A foo.c
   </pre>
   <p>
   Returns 0 if all files are successfully added.
   </p>
   <p>
   options ([+] can be repeated):
   </p>
   <table>
   <tr><td>-I</td>
   <td>--include PATTERN [+]</td>
   <td>include names matching the given patterns</td></tr>
   <tr><td>-X</td>
   <td>--exclude PATTERN [+]</td>
   <td>exclude names matching the given patterns</td></tr>
   <tr><td>-S</td>
   <td>--subrepos</td>
   <td>recurse into subrepositories</td></tr>
   <tr><td>-n</td>
   <td>--dry-run</td>
   <td>do not perform actions, just print output</td></tr>
   </table>
   <p>
   global options ([+] can be repeated):
   </p>
   <table>
   <tr><td>-R</td>
   <td>--repository REPO</td>
   <td>repository root directory or name of overlay bundle file</td></tr>
   <tr><td></td>
   <td>--cwd DIR</td>
   <td>change working directory</td></tr>
   <tr><td>-y</td>
   <td>--noninteractive</td>
   <td>do not prompt, automatically pick the first choice for all prompts</td></tr>
   <tr><td>-q</td>
   <td>--quiet</td>
   <td>suppress output</td></tr>
   <tr><td>-v</td>
   <td>--verbose</td>
   <td>enable additional output</td></tr>
   <tr><td></td>
   <td>--config CONFIG [+]</td>
   <td>set/override config option (use 'section.name=value')</td></tr>
   <tr><td></td>
   <td>--debug</td>
   <td>enable debugging output</td></tr>
   <tr><td></td>
   <td>--debugger</td>
   <td>start debugger</td></tr>
   <tr><td></td>
   <td>--encoding ENCODE</td>
   <td>set the charset encoding (default: ascii)</td></tr>
   <tr><td></td>
   <td>--encodingmode MODE</td>
   <td>set the charset encoding mode (default: strict)</td></tr>
   <tr><td></td>
   <td>--traceback</td>
   <td>always print a traceback on exception</td></tr>
   <tr><td></td>
   <td>--time</td>
   <td>time how long the command takes</td></tr>
   <tr><td></td>
   <td>--profile</td>
   <td>print command execution profile</td></tr>
   <tr><td></td>
   <td>--version</td>
   <td>output version information and exit</td></tr>
   <tr><td>-h</td>
   <td>--help</td>
   <td>display help and exit</td></tr>
   <tr><td></td>
   <td>--hidden</td>
   <td>consider hidden changesets</td></tr>
   </table>
   
   </div>
   </div>
   </div>
   
   <script type="text/javascript">process_dates()</script>
   
   
   </body>
   </html>
   
 
   $ get-with-headers.py 127.0.0.1:$HGPORT "help/remove"
   200 Script output follows
   
   <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
   <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-US">
   <head>
   <link rel="icon" href="/static/hgicon.png" type="image/png" />
   <meta name="robots" content="index, nofollow" />
   <link rel="stylesheet" href="/static/style-paper.css" type="text/css" />
   <script type="text/javascript" src="/static/mercurial.js"></script>
   
   <title>Help: remove</title>
   </head>
   <body>
   
   <div class="container">
   <div class="menu">
   <div class="logo">
   <a href="https://mercurial-scm.org/">
   <img src="/static/hglogo.png" alt="mercurial" /></a>
   </div>
   <ul>
   <li><a href="/shortlog">log</a></li>
   <li><a href="/graph">graph</a></li>
   <li><a href="/tags">tags</a></li>
   <li><a href="/bookmarks">bookmarks</a></li>
   <li><a href="/branches">branches</a></li>
   </ul>
   <ul>
    <li class="active"><a href="/help">help</a></li>
   </ul>
   </div>
   
   <div class="main">
   <h2 class="breadcrumb"><a href="/">Mercurial</a> </h2>
   <h3>Help: remove</h3>
   
   <form class="search" action="/log">
   
   <p><input name="rev" id="search1" type="text" size="30" /></p>
   <div id="hint">Find changesets by keywords (author, files, the commit message), revision
   number or hash, or <a href="/help/revsets">revset expression</a>.</div>
   </form>
   <div id="doc">
   <p>
   hg remove [OPTION]... FILE...
   </p>
   <p>
   aliases: rm
   </p>
   <p>
   remove the specified files on the next commit
   </p>
   <p>
   Schedule the indicated files for removal from the current branch.
   </p>
   <p>
   This command schedules the files to be removed at the next commit.
   To undo a remove before that, see &quot;hg revert&quot;. To undo added
   files, see &quot;hg forget&quot;.
   </p>
   <p>
   -A/--after can be used to remove only files that have already
   been deleted, -f/--force can be used to force deletion, and -Af
   can be used to remove files from the next revision without
   deleting them from the working directory.
   </p>
   <p>
   The following table details the behavior of remove for different
   file states (columns) and option combinations (rows). The file
   states are Added [A], Clean [C], Modified [M] and Missing [!]
   (as reported by &quot;hg status&quot;). The actions are Warn, Remove
   (from branch) and Delete (from disk):
   </p>
   <table>
   <tr><td>opt/state</td>
   <td>A</td>
   <td>C</td>
   <td>M</td>
   <td>!</td></tr>
   <tr><td>none</td>
   <td>W</td>
   <td>RD</td>
   <td>W</td>
   <td>R</td></tr>
   <tr><td>-f</td>
   <td>R</td>
   <td>RD</td>
   <td>RD</td>
   <td>R</td></tr>
   <tr><td>-A</td>
   <td>W</td>
   <td>W</td>
   <td>W</td>
   <td>R</td></tr>
   <tr><td>-Af</td>
   <td>R</td>
   <td>R</td>
   <td>R</td>
   <td>R</td></tr>
   </table>
   <p>
   Note that remove never deletes files in Added [A] state from the
   working directory, not even if option --force is specified.
   </p>
   <p>
   Returns 0 on success, 1 if any warnings encountered.
   </p>
   <p>
   options ([+] can be repeated):
   </p>
   <table>
   <tr><td>-A</td>
   <td>--after</td>
   <td>record delete for missing files</td></tr>
   <tr><td>-f</td>
   <td>--force</td>
   <td>remove (and delete) file even if added or modified</td></tr>
   <tr><td>-S</td>
   <td>--subrepos</td>
   <td>recurse into subrepositories</td></tr>
   <tr><td>-I</td>
   <td>--include PATTERN [+]</td>
   <td>include names matching the given patterns</td></tr>
   <tr><td>-X</td>
   <td>--exclude PATTERN [+]</td>
   <td>exclude names matching the given patterns</td></tr>
   </table>
   <p>
   global options ([+] can be repeated):
   </p>
   <table>
   <tr><td>-R</td>
   <td>--repository REPO</td>
   <td>repository root directory or name of overlay bundle file</td></tr>
   <tr><td></td>
   <td>--cwd DIR</td>
   <td>change working directory</td></tr>
   <tr><td>-y</td>
   <td>--noninteractive</td>
   <td>do not prompt, automatically pick the first choice for all prompts</td></tr>
   <tr><td>-q</td>
   <td>--quiet</td>
   <td>suppress output</td></tr>
   <tr><td>-v</td>
   <td>--verbose</td>
   <td>enable additional output</td></tr>
   <tr><td></td>
   <td>--config CONFIG [+]</td>
   <td>set/override config option (use 'section.name=value')</td></tr>
   <tr><td></td>
   <td>--debug</td>
   <td>enable debugging output</td></tr>
   <tr><td></td>
   <td>--debugger</td>
   <td>start debugger</td></tr>
   <tr><td></td>
   <td>--encoding ENCODE</td>
   <td>set the charset encoding (default: ascii)</td></tr>
   <tr><td></td>
   <td>--encodingmode MODE</td>
   <td>set the charset encoding mode (default: strict)</td></tr>
   <tr><td></td>
   <td>--traceback</td>
   <td>always print a traceback on exception</td></tr>
   <tr><td></td>
   <td>--time</td>
   <td>time how long the command takes</td></tr>
   <tr><td></td>
   <td>--profile</td>
   <td>print command execution profile</td></tr>
   <tr><td></td>
   <td>--version</td>
   <td>output version information and exit</td></tr>
   <tr><td>-h</td>
   <td>--help</td>
   <td>display help and exit</td></tr>
   <tr><td></td>
   <td>--hidden</td>
   <td>consider hidden changesets</td></tr>
   </table>
   
   </div>
   </div>
   </div>
   
   <script type="text/javascript">process_dates()</script>
   
   
   </body>
   </html>
   
 
   $ get-with-headers.py 127.0.0.1:$HGPORT "help/revisions"
   200 Script output follows
   
   <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
   <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-US">
   <head>
   <link rel="icon" href="/static/hgicon.png" type="image/png" />
   <meta name="robots" content="index, nofollow" />
   <link rel="stylesheet" href="/static/style-paper.css" type="text/css" />
   <script type="text/javascript" src="/static/mercurial.js"></script>
   
   <title>Help: revisions</title>
   </head>
   <body>
   
   <div class="container">
   <div class="menu">
   <div class="logo">
   <a href="https://mercurial-scm.org/">
   <img src="/static/hglogo.png" alt="mercurial" /></a>
   </div>
   <ul>
   <li><a href="/shortlog">log</a></li>
   <li><a href="/graph">graph</a></li>
   <li><a href="/tags">tags</a></li>
   <li><a href="/bookmarks">bookmarks</a></li>
   <li><a href="/branches">branches</a></li>
   </ul>
   <ul>
    <li class="active"><a href="/help">help</a></li>
   </ul>
   </div>
   
   <div class="main">
   <h2 class="breadcrumb"><a href="/">Mercurial</a> </h2>
   <h3>Help: revisions</h3>
   
   <form class="search" action="/log">
   
   <p><input name="rev" id="search1" type="text" size="30" /></p>
   <div id="hint">Find changesets by keywords (author, files, the commit message), revision
   number or hash, or <a href="/help/revsets">revset expression</a>.</div>
   </form>
   <div id="doc">
   <h1>Specifying Single Revisions</h1>
   <p>
   Mercurial supports several ways to specify individual revisions.
   </p>
   <p>
   A plain integer is treated as a revision number. Negative integers are
   treated as sequential offsets from the tip, with -1 denoting the tip,
   -2 denoting the revision prior to the tip, and so forth.
   </p>
   <p>
   A 40-digit hexadecimal string is treated as a unique revision
   identifier.
   </p>
   <p>
   A hexadecimal string less than 40 characters long is treated as a
   unique revision identifier and is referred to as a short-form
   identifier. A short-form identifier is only valid if it is the prefix
   of exactly one full-length identifier.
   </p>
   <p>
   Any other string is treated as a bookmark, tag, or branch name. A
   bookmark is a movable pointer to a revision. A tag is a permanent name
   associated with a revision. A branch name denotes the tipmost open branch head
   of that branch - or if they are all closed, the tipmost closed head of the
   branch. Bookmark, tag, and branch names must not contain the &quot;:&quot; character.
   </p>
   <p>
   The reserved name &quot;tip&quot; always identifies the most recent revision.
   </p>
   <p>
   The reserved name &quot;null&quot; indicates the null revision. This is the
   revision of an empty repository, and the parent of revision 0.
   </p>
   <p>
   The reserved name &quot;.&quot; indicates the working directory parent. If no
   working directory is checked out, it is equivalent to null. If an
   uncommitted merge is in progress, &quot;.&quot; is the revision of the first
   parent.
   </p>
   
   </div>
   </div>
   </div>
   
   <script type="text/javascript">process_dates()</script>
   
   
   </body>
   </html>
   
 
   $ killdaemons.py
 
 #endif