exchange: improve computation of relevant markers for large repos

Compute the candidate nodes with relevant markers directly
from keys of the predecessors/successors/children dictionaries of
obsstore. This is faster than iterating over all nodes directly.
This test could be further improved for repositories with relative
few markers compared to the repository size, but this is no longer
hot already. With the current loop structure, the obshashrange use
works as well as before as it passes lists with a single node.

Adjust the interface by allowing revision lists as well as node lists.
This helps cases that computes ancestors as it reduces the
materialisation cost. Use this in _pushdiscoveryobsmarker and
_getbundleobsmarkerpart. Improve the latter further by directly using
ancestors().


Performance benchmarks show notable and welcome improvement to no-op push and
pull (that would also apply to other push/pull). This apply to push and pull
done without evolve.

### push/pull Benchmark parameter
  # bin-env-vars.hg.flavor          = default
  # benchmark.variants.explicit-rev = none
  # benchmark.variants.protocol     = ssh
  # benchmark.variants.revs         = none

 ## benchmark.name                  = hg.command.pull
  # data-env-vars.name              = mercurial-devel-2024-03-22-zstd-sparse-revlog
before: 5.968537 seconds
after:  5.668507 seconds (-5.03%, -0.30)
  # data-env-vars.name              = tryton-devel-2024-03-22-zstd-sparse-revlog
before: 1.446232 seconds
after:  0.835553 seconds (-42.23%, -0.61)
  # data-env-vars.name              = netbsd-src-draft-2024-09-19-zstd-sparse-revlog
before: 5.777412 seconds
after:  2.523454 seconds (-56.32%, -3.25)

 ## benchmark.name                  = hg.command.push
  # data-env-vars.name              = mercurial-devel-2024-03-22-zstd-sparse-revlog
before: 6.155501 seconds
after:  5.885072 seconds (-4.39%, -0.27)

  # data-env-vars.name              = tryton-devel-2024-03-22-zstd-sparse-revlog
before: 1.491054 seconds
after:  0.934882 seconds (-37.30%, -0.56)

  # data-env-vars.name              = netbsd-src-draft-2024-09-19-zstd-sparse-revlog
before: 5.902494 seconds
after:  2.957644 seconds (-49.89%, -2.94)

There is not notable different in these result using the "rust" flavor instead
of the "default".  The performance impact on the same operation when using
evolve were also tested and no impact was noted.

mercurial/bundle2.py

@@ -1,2690 +1,2690
 # bundle2.py - generic container format to transmit arbitrary data.
 #
 # Copyright 2013 Facebook, Inc.
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 """Handling of the new bundle2 format
 
 The goal of bundle2 is to act as an atomically packet to transmit a set of
 payloads in an application agnostic way. It consist in a sequence of "parts"
 that will be handed to and processed by the application layer.
 
 
 General format architecture
 ===========================
 
 The format is architectured as follow
 
  - magic string
  - stream level parameters
  - payload parts (any number)
  - end of stream marker.
 
 the Binary format
 ============================
 
 All numbers are unsigned and big-endian.
 
 stream level parameters
 ------------------------
 
 Binary format is as follow
 
 :params size: int32
 
   The total number of Bytes used by the parameters
 
 :params value: arbitrary number of Bytes
 
   A blob of `params size` containing the serialized version of all stream level
   parameters.
 
   The blob contains a space separated list of parameters. Parameters with value
   are stored in the form `<name>=<value>`. Both name and value are urlquoted.
 
   Empty name are obviously forbidden.
 
   Name MUST start with a letter. If this first letter is lower case, the
   parameter is advisory and can be safely ignored. However when the first
   letter is capital, the parameter is mandatory and the bundling process MUST
   stop if he is not able to proceed it.
 
   Stream parameters use a simple textual format for two main reasons:
 
   - Stream level parameters should remain simple and we want to discourage any
     crazy usage.
   - Textual data allow easy human inspection of a bundle2 header in case of
     troubles.
 
   Any Applicative level options MUST go into a bundle2 part instead.
 
 Payload part
 ------------------------
 
 Binary format is as follow
 
 :header size: int32
 
   The total number of Bytes used by the part header. When the header is empty
   (size = 0) this is interpreted as the end of stream marker.
 
 :header:
 
     The header defines how to interpret the part. It contains two piece of
     data: the part type, and the part parameters.
 
     The part type is used to route an application level handler, that can
     interpret payload.
 
     Part parameters are passed to the application level handler.  They are
     meant to convey information that will help the application level object to
     interpret the part payload.
 
     The binary format of the header is has follow
 
     :typesize: (one byte)
 
     :parttype: alphanumerical part name (restricted to [a-zA-Z0-9_:-]*)
 
     :partid: A 32bits integer (unique in the bundle) that can be used to refer
              to this part.
 
     :parameters:
 
         Part's parameter may have arbitrary content, the binary structure is::
 
             <mandatory-count><advisory-count><param-sizes><param-data>
 
         :mandatory-count: 1 byte, number of mandatory parameters
 
         :advisory-count:  1 byte, number of advisory parameters
 
         :param-sizes:
 
             N couple of bytes, where N is the total number of parameters. Each
             couple contains (<size-of-key>, <size-of-value) for one parameter.
 
         :param-data:
 
             A blob of bytes from which each parameter key and value can be
             retrieved using the list of size couples stored in the previous
             field.
 
             Mandatory parameters comes first, then the advisory ones.
 
             Each parameter's key MUST be unique within the part.
 
 :payload:
 
     payload is a series of `<chunksize><chunkdata>`.
 
     `chunksize` is an int32, `chunkdata` are plain bytes (as much as
     `chunksize` says)` The payload part is concluded by a zero size chunk.
 
     The current implementation always produces either zero or one chunk.
     This is an implementation limitation that will ultimately be lifted.
 
     `chunksize` can be negative to trigger special case processing. No such
     processing is in place yet.
 
 Bundle processing
 ============================
 
 Each part is processed in order using a "part handler". Handler are registered
 for a certain part type.
 
 The matching of a part to its handler is case insensitive. The case of the
 part type is used to know if a part is mandatory or advisory. If the Part type
 contains any uppercase char it is considered mandatory. When no handler is
 known for a Mandatory part, the process is aborted and an exception is raised.
 If the part is advisory and no handler is known, the part is ignored. When the
 process is aborted, the full bundle is still read from the stream to keep the
 channel usable. But none of the part read from an abort are processed. In the
 future, dropping the stream may become an option for channel we do not care to
 preserve.
 """
 
 from __future__ import annotations
 
 import collections
 import errno
 import os
 import re
 import string
 import struct
 import sys
 import typing
 
 from .i18n import _
 from .node import (
     hex,
     short,
 )
 from . import (
     bookmarks,
     changegroup,
     encoding,
     error,
     obsolete,
     phases,
     pushkey,
     pycompat,
     requirements,
     scmutil,
     streamclone,
     tags,
     url,
     util,
 )
 from .utils import (
     stringutil,
     urlutil,
 )
 from .interfaces import repository
 
 if typing.TYPE_CHECKING:
     from typing import (
         Dict,
         List,
         Optional,
         Tuple,
         Union,
     )
 
     Capabilities = Dict[bytes, Union[List[bytes], Tuple[bytes, ...]]]
 
 urlerr = util.urlerr
 urlreq = util.urlreq
 
 _pack = struct.pack
 _unpack = struct.unpack
 
 _fstreamparamsize = b'>i'
 _fpartheadersize = b'>i'
 _fparttypesize = b'>B'
 _fpartid = b'>I'
 _fpayloadsize = b'>i'
 _fpartparamcount = b'>BB'
 
 preferedchunksize = 32768
 
 _parttypeforbidden = re.compile(b'[^a-zA-Z0-9_:-]')
 
 
 def outdebug(ui, message):
     """debug regarding output stream (bundling)"""
     if ui.configbool(b'devel', b'bundle2.debug'):
         ui.debug(b'bundle2-output: %s\n' % message)
 
 
 def indebug(ui, message):
     """debug on input stream (unbundling)"""
     if ui.configbool(b'devel', b'bundle2.debug'):
         ui.debug(b'bundle2-input: %s\n' % message)
 
 
 def validateparttype(parttype):
     """raise ValueError if a parttype contains invalid character"""
     if _parttypeforbidden.search(parttype):
         raise ValueError(parttype)
 
 
 def _makefpartparamsizes(nbparams):
     """return a struct format to read part parameter sizes
 
     The number parameters is variable so we need to build that format
     dynamically.
     """
     return b'>' + (b'BB' * nbparams)
 
 
 parthandlermapping = {}
 
 
 def parthandler(parttype, params=()):
     """decorator that register a function as a bundle2 part handler
 
     eg::
 
         @parthandler('myparttype', ('mandatory', 'param', 'handled'))
         def myparttypehandler(...):
             '''process a part of type "my part".'''
             ...
     """
     validateparttype(parttype)
 
     def _decorator(func):
         lparttype = parttype.lower()  # enforce lower case matching.
         assert lparttype not in parthandlermapping
         parthandlermapping[lparttype] = func
         func.params = frozenset(params)
         return func
 
     return _decorator
 
 
 class unbundlerecords:
     """keep record of what happens during and unbundle
 
     New records are added using `records.add('cat', obj)`. Where 'cat' is a
     category of record and obj is an arbitrary object.
 
     `records['cat']` will return all entries of this category 'cat'.
 
     Iterating on the object itself will yield `('category', obj)` tuples
     for all entries.
 
     All iterations happens in chronological order.
     """
 
     def __init__(self):
         self._categories = {}
         self._sequences = []
         self._replies = {}
 
     def add(self, category, entry, inreplyto=None):
         """add a new record of a given category.
 
         The entry can then be retrieved in the list returned by
         self['category']."""
         self._categories.setdefault(category, []).append(entry)
         self._sequences.append((category, entry))
         if inreplyto is not None:
             self.getreplies(inreplyto).add(category, entry)
 
     def getreplies(self, partid):
         """get the records that are replies to a specific part"""
         return self._replies.setdefault(partid, unbundlerecords())
 
     def __getitem__(self, cat):
         return tuple(self._categories.get(cat, ()))
 
     def __iter__(self):
         return iter(self._sequences)
 
     def __len__(self):
         return len(self._sequences)
 
     def __nonzero__(self):
         return bool(self._sequences)
 
     __bool__ = __nonzero__
 
 
 class bundleoperation:
     """an object that represents a single bundling process
 
     Its purpose is to carry unbundle-related objects and states.
 
     A new object should be created at the beginning of each bundle processing.
     The object is to be returned by the processing function.
 
     The object has very little content now it will ultimately contain:
     * an access to the repo the bundle is applied to,
     * a ui object,
     * a way to retrieve a transaction to add changes to the repo,
     * a way to record the result of processing each part,
     * a way to construct a bundle response when applicable.
     """
 
     def __init__(
         self,
         repo,
         transactiongetter,
         captureoutput=True,
         source=b'',
         remote=None,
     ):
         self.repo = repo
         # the peer object who produced this bundle if available
         self.remote = remote
         self.ui = repo.ui
         self.records = unbundlerecords()
         self.reply = None
         self.captureoutput = captureoutput
         self.hookargs = {}
         self._gettransaction = transactiongetter
         # carries value that can modify part behavior
         self.modes = {}
         self.source = source
 
     def gettransaction(self):
         transaction = self._gettransaction()
 
         if self.hookargs:
             # the ones added to the transaction supercede those added
             # to the operation.
             self.hookargs.update(transaction.hookargs)
             transaction.hookargs = self.hookargs
 
         # mark the hookargs as flushed.  further attempts to add to
         # hookargs will result in an abort.
         self.hookargs = None
 
         return transaction
 
     def addhookargs(self, hookargs):
         if self.hookargs is None:
             raise error.ProgrammingError(
                 b'attempted to add hookargs to '
                 b'operation after transaction started'
             )
         self.hookargs.update(hookargs)
 
 
 class TransactionUnavailable(RuntimeError):
     pass
 
 
 def _notransaction():
     """default method to get a transaction while processing a bundle
 
     Raise an exception to highlight the fact that no transaction was expected
     to be created"""
     raise TransactionUnavailable()
 
 
 def applybundle(repo, unbundler, tr, source, url=None, remote=None, **kwargs):
     # transform me into unbundler.apply() as soon as the freeze is lifted
     if isinstance(unbundler, unbundle20):
         tr.hookargs[b'bundle2'] = b'1'
         if source is not None and b'source' not in tr.hookargs:
             tr.hookargs[b'source'] = source
         if url is not None and b'url' not in tr.hookargs:
             tr.hookargs[b'url'] = url
         return processbundle(
             repo, unbundler, lambda: tr, source=source, remote=remote
         )
     else:
         # the transactiongetter won't be used, but we might as well set it
         op = bundleoperation(repo, lambda: tr, source=source, remote=remote)
         _processchangegroup(op, unbundler, tr, source, url, **kwargs)
         return op
 
 
 class partiterator:
     def __init__(self, repo, op, unbundler):
         self.repo = repo
         self.op = op
         self.unbundler = unbundler
         self.iterator = None
         self.count = 0
         self.current = None
 
     def __enter__(self):
         def func():
             itr = enumerate(self.unbundler.iterparts(), 1)
             for count, p in itr:
                 self.count = count
                 self.current = p
                 yield p
                 p.consume()
                 self.current = None
 
         self.iterator = func()
         return self.iterator
 
     def __exit__(self, type, exc, tb):
         if not self.iterator:
             return
 
         # Only gracefully abort in a normal exception situation. User aborts
         # like Ctrl+C throw a KeyboardInterrupt which is not a base Exception,
         # and should not gracefully cleanup.
         if isinstance(exc, Exception):
             # Any exceptions seeking to the end of the bundle at this point are
             # almost certainly related to the underlying stream being bad.
             # And, chances are that the exception we're handling is related to
             # getting in that bad state. So, we swallow the seeking error and
             # re-raise the original error.
             seekerror = False
             try:
                 if self.current:
                     # consume the part content to not corrupt the stream.
                     self.current.consume()
 
                 for part in self.iterator:
                     # consume the bundle content
                     part.consume()
             except Exception:
                 seekerror = True
 
             # Small hack to let caller code distinguish exceptions from bundle2
             # processing from processing the old format. This is mostly needed
             # to handle different return codes to unbundle according to the type
             # of bundle. We should probably clean up or drop this return code
             # craziness in a future version.
             exc.duringunbundle2 = True
             salvaged = []
             replycaps = None
             if self.op.reply is not None:
                 salvaged = self.op.reply.salvageoutput()
                 replycaps = self.op.reply.capabilities
             exc._replycaps = replycaps
             exc._bundle2salvagedoutput = salvaged
 
             # Re-raising from a variable loses the original stack. So only use
             # that form if we need to.
             if seekerror:
                 raise exc
 
         self.repo.ui.debug(
             b'bundle2-input-bundle: %i parts total\n' % self.count
         )
 
 
 def processbundle(
     repo,
     unbundler,
     transactiongetter=None,
     op=None,
     source=b'',
     remote=None,
 ):
     """This function process a bundle, apply effect to/from a repo
 
     It iterates over each part then searches for and uses the proper handling
     code to process the part. Parts are processed in order.
 
     Unknown Mandatory part will abort the process.
 
     It is temporarily possible to provide a prebuilt bundleoperation to the
     function. This is used to ensure output is properly propagated in case of
     an error during the unbundling. This output capturing part will likely be
     reworked and this ability will probably go away in the process.
     """
     if op is None:
         if transactiongetter is None:
             transactiongetter = _notransaction
         op = bundleoperation(
             repo,
             transactiongetter,
             source=source,
             remote=remote,
         )
     # todo:
     # - replace this is a init function soon.
     # - exception catching
     unbundler.params
     if repo.ui.debugflag:
         msg = [b'bundle2-input-bundle:']
         if unbundler.params:
             msg.append(b' %i params' % len(unbundler.params))
         if op._gettransaction is None or op._gettransaction is _notransaction:
             msg.append(b' no-transaction')
         else:
             msg.append(b' with-transaction')
         msg.append(b'\n')
         repo.ui.debug(b''.join(msg))
 
     processparts(repo, op, unbundler)
 
     return op
 
 
 def processparts(repo, op, unbundler):
     with partiterator(repo, op, unbundler) as parts:
         for part in parts:
             _processpart(op, part)
 
 
 def _processchangegroup(op, cg, tr, source, url, **kwargs):
     if op.remote is not None and op.remote.path is not None:
         remote_path = op.remote.path
         kwargs = kwargs.copy()
         kwargs['delta_base_reuse_policy'] = remote_path.delta_reuse_policy
     ret = cg.apply(op.repo, tr, source, url, **kwargs)
     op.records.add(
         b'changegroup',
         {
             b'return': ret,
         },
     )
     return ret
 
 
 def _gethandler(op, part):
     status = b'unknown'  # used by debug output
     try:
         handler = parthandlermapping.get(part.type)
         if handler is None:
             status = b'unsupported-type'
             raise error.BundleUnknownFeatureError(parttype=part.type)
         indebug(op.ui, b'found a handler for part %s' % part.type)
         unknownparams = part.mandatorykeys - handler.params
         if unknownparams:
             unknownparams = list(unknownparams)
             unknownparams.sort()
             status = b'unsupported-params (%s)' % b', '.join(unknownparams)
             raise error.BundleUnknownFeatureError(
                 parttype=part.type, params=unknownparams
             )
         status = b'supported'
     except error.BundleUnknownFeatureError as exc:
         if part.mandatory:  # mandatory parts
             raise
         indebug(op.ui, b'ignoring unsupported advisory part %s' % exc)
         return  # skip to part processing
     finally:
         if op.ui.debugflag:
             msg = [b'bundle2-input-part: "%s"' % part.type]
             if not part.mandatory:
                 msg.append(b' (advisory)')
             nbmp = len(part.mandatorykeys)
             nbap = len(part.params) - nbmp
             if nbmp or nbap:
                 msg.append(b' (params:')
                 if nbmp:
                     msg.append(b' %i mandatory' % nbmp)
                 if nbap:
                     msg.append(b' %i advisory' % nbmp)
                 msg.append(b')')
             msg.append(b' %s\n' % status)
             op.ui.debug(b''.join(msg))
 
     return handler
 
 
 def _processpart(op, part):
     """process a single part from a bundle
 
     The part is guaranteed to have been fully consumed when the function exits
     (even if an exception is raised)."""
     handler = _gethandler(op, part)
     if handler is None:
         return
 
     # handler is called outside the above try block so that we don't
     # risk catching KeyErrors from anything other than the
     # parthandlermapping lookup (any KeyError raised by handler()
     # itself represents a defect of a different variety).
     output = None
     if op.captureoutput and op.reply is not None:
         op.ui.pushbuffer(error=True, subproc=True)
         output = b''
     try:
         handler(op, part)
     finally:
         if output is not None:
             output = op.ui.popbuffer()
         if output:
             outpart = op.reply.newpart(b'output', data=output, mandatory=False)
             outpart.addparam(
                 b'in-reply-to', pycompat.bytestr(part.id), mandatory=False
             )
 
 
 def decodecaps(blob: bytes) -> "Capabilities":
     """decode a bundle2 caps bytes blob into a dictionary
 
     The blob is a list of capabilities (one per line)
     Capabilities may have values using a line of the form::
 
         capability=value1,value2,value3
 
     The values are always a list."""
     caps = {}
     for line in blob.splitlines():
         if not line:
             continue
         if b'=' not in line:
             key, vals = line, ()
         else:
             key, vals = line.split(b'=', 1)
             vals = vals.split(b',')
         key = urlreq.unquote(key)
         vals = [urlreq.unquote(v) for v in vals]
         caps[key] = vals
     return caps
 
 
 def encodecaps(caps):
     """encode a bundle2 caps dictionary into a bytes blob"""
     chunks = []
     for ca in sorted(caps):
         vals = caps[ca]
         ca = urlreq.quote(ca)
         vals = [urlreq.quote(v) for v in vals]
         if vals:
             ca = b"%s=%s" % (ca, b','.join(vals))
         chunks.append(ca)
     return b'\n'.join(chunks)
 
 
 bundletypes = {
     b"": (b"", b'UN'),  # only when using unbundle on ssh and old http servers
     # since the unification ssh accepts a header but there
     # is no capability signaling it.
     b"HG20": (),  # special-cased below
     b"HG10UN": (b"HG10UN", b'UN'),
     b"HG10BZ": (b"HG10", b'BZ'),
     b"HG10GZ": (b"HG10GZ", b'GZ'),
 }
 
 # hgweb uses this list to communicate its preferred type
 bundlepriority = [b'HG10GZ', b'HG10BZ', b'HG10UN']
 
 
 class bundle20:
     """represent an outgoing bundle2 container
 
     Use the `addparam` method to add stream level parameter. and `newpart` to
     populate it. Then call `getchunks` to retrieve all the binary chunks of
     data that compose the bundle2 container."""
 
     _magicstring = b'HG20'
 
     def __init__(self, ui, capabilities: "Optional[Capabilities]" = None):
         if capabilities is None:
             capabilities = {}
 
         self.ui = ui
         self._params = []
         self._parts = []
         self.capabilities: "Capabilities" = dict(capabilities)
         self._compengine = util.compengines.forbundletype(b'UN')
         self._compopts = None
         # If compression is being handled by a consumer of the raw
         # data (e.g. the wire protocol), unsetting this flag tells
         # consumers that the bundle is best left uncompressed.
         self.prefercompressed = True
 
     def setcompression(self, alg, compopts=None):
         """setup core part compression to <alg>"""
         if alg in (None, b'UN'):
             return
         assert not any(n.lower() == b'compression' for n, v in self._params)
         self.addparam(b'Compression', alg)
         self._compengine = util.compengines.forbundletype(alg)
         self._compopts = compopts
 
     @property
     def nbparts(self):
         """total number of parts added to the bundler"""
         return len(self._parts)
 
     # methods used to defines the bundle2 content
     def addparam(self, name, value=None):
         """add a stream level parameter"""
         if not name:
             raise error.ProgrammingError(b'empty parameter name')
         if name[0:1] not in pycompat.bytestr(
             string.ascii_letters  # pytype: disable=wrong-arg-types
         ):
             raise error.ProgrammingError(
                 b'non letter first character: %s' % name
             )
         self._params.append((name, value))
 
     def addpart(self, part):
         """add a new part to the bundle2 container
 
         Parts contains the actual applicative payload."""
         assert part.id is None
         part.id = len(self._parts)  # very cheap counter
         self._parts.append(part)
 
     def newpart(self, typeid, *args, **kwargs):
         """create a new part and add it to the containers
 
         As the part is directly added to the containers. For now, this means
         that any failure to properly initialize the part after calling
         ``newpart`` should result in a failure of the whole bundling process.
 
         You can still fall back to manually create and add if you need better
         control."""
         part = bundlepart(typeid, *args, **kwargs)
         self.addpart(part)
         return part
 
     # methods used to generate the bundle2 stream
     def getchunks(self):
         if self.ui.debugflag:
             msg = [b'bundle2-output-bundle: "%s",' % self._magicstring]
             if self._params:
                 msg.append(b' (%i params)' % len(self._params))
             msg.append(b' %i parts total\n' % len(self._parts))
             self.ui.debug(b''.join(msg))
         outdebug(self.ui, b'start emission of %s stream' % self._magicstring)
         yield self._magicstring
         param = self._paramchunk()
         outdebug(self.ui, b'bundle parameter: %s' % param)
         yield _pack(_fstreamparamsize, len(param))
         if param:
             yield param
         for chunk in self._compengine.compressstream(
             self._getcorechunk(), self._compopts
         ):
             yield chunk
 
     def _paramchunk(self):
         """return a encoded version of all stream parameters"""
         blocks = []
         for par, value in self._params:
             par = urlreq.quote(par)
             if value is not None:
                 value = urlreq.quote(value)
                 par = b'%s=%s' % (par, value)
             blocks.append(par)
         return b' '.join(blocks)
 
     def _getcorechunk(self):
         """yield chunk for the core part of the bundle
 
         (all but headers and parameters)"""
         outdebug(self.ui, b'start of parts')
         for part in self._parts:
             outdebug(self.ui, b'bundle part: "%s"' % part.type)
             for chunk in part.getchunks(ui=self.ui):
                 yield chunk
         outdebug(self.ui, b'end of bundle')
         yield _pack(_fpartheadersize, 0)
 
     def salvageoutput(self):
         """return a list with a copy of all output parts in the bundle
 
         This is meant to be used during error handling to make sure we preserve
         server output"""
         salvaged = []
         for part in self._parts:
             if part.type.startswith(b'output'):
                 salvaged.append(part.copy())
         return salvaged
 
 
 class unpackermixin:
     """A mixin to extract bytes and struct data from a stream"""
 
     def __init__(self, fp):
         self._fp = fp
 
     def _unpack(self, format):
         """unpack this struct format from the stream
 
         This method is meant for internal usage by the bundle2 protocol only.
         They directly manipulate the low level stream including bundle2 level
         instruction.
 
         Do not use it to implement higher-level logic or methods."""
         data = self._readexact(struct.calcsize(format))
         return _unpack(format, data)
 
     def _readexact(self, size):
         """read exactly <size> bytes from the stream
 
         This method is meant for internal usage by the bundle2 protocol only.
         They directly manipulate the low level stream including bundle2 level
         instruction.
 
         Do not use it to implement higher-level logic or methods."""
         return changegroup.readexactly(self._fp, size)
 
 
 def getunbundler(ui, fp, magicstring=None):
     """return a valid unbundler object for a given magicstring"""
     if magicstring is None:
         magicstring = changegroup.readexactly(fp, 4)
     magic, version = magicstring[0:2], magicstring[2:4]
     if magic != b'HG':
         ui.debug(
             b"error: invalid magic: %r (version %r), should be 'HG'\n"
             % (magic, version)
         )
         raise error.Abort(_(b'not a Mercurial bundle'))
     unbundlerclass = formatmap.get(version)
     if unbundlerclass is None:
         raise error.Abort(_(b'unknown bundle version %s') % version)
     unbundler = unbundlerclass(ui, fp)
     indebug(ui, b'start processing of %s stream' % magicstring)
     return unbundler
 
 
 class unbundle20(unpackermixin):
     """interpret a bundle2 stream
 
     This class is fed with a binary stream and yields parts through its
     `iterparts` methods."""
 
     _magicstring = b'HG20'
 
     def __init__(self, ui, fp):
         """If header is specified, we do not read it out of the stream."""
         self.ui = ui
         self._compengine = util.compengines.forbundletype(b'UN')
         self._compressed = None
         super(unbundle20, self).__init__(fp)
 
     @util.propertycache
     def params(self):
         """dictionary of stream level parameters"""
         indebug(self.ui, b'reading bundle2 stream parameters')
         params = {}
         paramssize = self._unpack(_fstreamparamsize)[0]
         if paramssize < 0:
             raise error.BundleValueError(
                 b'negative bundle param size: %i' % paramssize
             )
         if paramssize:
             params = self._readexact(paramssize)
             params = self._processallparams(params)
         return params
 
     def _processallparams(self, paramsblock):
         """ """
         params = util.sortdict()
         for p in paramsblock.split(b' '):
             p = p.split(b'=', 1)
             p = [urlreq.unquote(i) for i in p]
             if len(p) < 2:
                 p.append(None)
             self._processparam(*p)
             params[p[0]] = p[1]
         return params
 
     def _processparam(self, name, value):
         """process a parameter, applying its effect if needed
 
         Parameter starting with a lower case letter are advisory and will be
         ignored when unknown.  Those starting with an upper case letter are
         mandatory and will this function will raise a KeyError when unknown.
 
         Note: no option are currently supported. Any input will be either
               ignored or failing.
         """
         if not name:
             raise ValueError('empty parameter name')
         if name[0:1] not in pycompat.bytestr(
             string.ascii_letters  # pytype: disable=wrong-arg-types
         ):
             raise ValueError('non letter first character: %s' % name)
         try:
             handler = b2streamparamsmap[name.lower()]
         except KeyError:
             if name[0:1].islower():
                 indebug(self.ui, b"ignoring unknown parameter %s" % name)
             else:
                 raise error.BundleUnknownFeatureError(params=(name,))
         else:
             handler(self, name, value)
 
     def _forwardchunks(self):
         """utility to transfer a bundle2 as binary
 
         This is made necessary by the fact the 'getbundle' command over 'ssh'
         have no way to know when the reply ends, relying on the bundle to be
         interpreted to know its end. This is terrible and we are sorry, but we
         needed to move forward to get general delta enabled.
         """
         yield self._magicstring
         assert 'params' not in vars(self)
         paramssize = self._unpack(_fstreamparamsize)[0]
         if paramssize < 0:
             raise error.BundleValueError(
                 b'negative bundle param size: %i' % paramssize
             )
         if paramssize:
             params = self._readexact(paramssize)
             self._processallparams(params)
             # The payload itself is decompressed below, so drop
             # the compression parameter passed down to compensate.
             outparams = []
             for p in params.split(b' '):
                 k, v = p.split(b'=', 1)
                 if k.lower() != b'compression':
                     outparams.append(p)
             outparams = b' '.join(outparams)
             yield _pack(_fstreamparamsize, len(outparams))
             yield outparams
         else:
             yield _pack(_fstreamparamsize, paramssize)
         # From there, payload might need to be decompressed
         self._fp = self._compengine.decompressorreader(self._fp)
         emptycount = 0
         while emptycount < 2:
             # so we can brainlessly loop
             assert _fpartheadersize == _fpayloadsize
             size = self._unpack(_fpartheadersize)[0]
             yield _pack(_fpartheadersize, size)
             if size:
                 emptycount = 0
             else:
                 emptycount += 1
                 continue
             if size == flaginterrupt:
                 continue
             elif size < 0:
                 raise error.BundleValueError(b'negative chunk size: %i')
             yield self._readexact(size)
 
     def iterparts(self, seekable=False):
         """yield all parts contained in the stream"""
         cls = seekableunbundlepart if seekable else unbundlepart
         # make sure param have been loaded
         self.params
         # From there, payload need to be decompressed
         self._fp = self._compengine.decompressorreader(self._fp)
         indebug(self.ui, b'start extraction of bundle2 parts')
         headerblock = self._readpartheader()
         while headerblock is not None:
             part = cls(self.ui, headerblock, self._fp)
             yield part
             # Ensure part is fully consumed so we can start reading the next
             # part.
             part.consume()
 
             headerblock = self._readpartheader()
         indebug(self.ui, b'end of bundle2 stream')
 
     def _readpartheader(self):
         """reads a part header size and return the bytes blob
 
         returns None if empty"""
         headersize = self._unpack(_fpartheadersize)[0]
         if headersize < 0:
             raise error.BundleValueError(
                 b'negative part header size: %i' % headersize
             )
         indebug(self.ui, b'part header size: %i' % headersize)
         if headersize:
             return self._readexact(headersize)
         return None
 
     def compressed(self):
         self.params  # load params
         return self._compressed
 
     def close(self):
         """close underlying file"""
         if hasattr(self._fp, 'close'):
             return self._fp.close()
 
 
 formatmap = {b'20': unbundle20}
 
 b2streamparamsmap = {}
 
 
 def b2streamparamhandler(name):
     """register a handler for a stream level parameter"""
 
     def decorator(func):
         assert name not in formatmap
         b2streamparamsmap[name] = func
         return func
 
     return decorator
 
 
 @b2streamparamhandler(b'compression')
 def processcompression(unbundler, param, value):
     """read compression parameter and install payload decompression"""
     if value not in util.compengines.supportedbundletypes:
         raise error.BundleUnknownFeatureError(params=(param,), values=(value,))
     unbundler._compengine = util.compengines.forbundletype(value)
     if value is not None:
         unbundler._compressed = True
 
 
 class bundlepart:
     """A bundle2 part contains application level payload
 
     The part `type` is used to route the part to the application level
     handler.
 
     The part payload is contained in ``part.data``. It could be raw bytes or a
     generator of byte chunks.
 
     You can add parameters to the part using the ``addparam`` method.
     Parameters can be either mandatory (default) or advisory. Remote side
     should be able to safely ignore the advisory ones.
 
     Both data and parameters cannot be modified after the generation has begun.
     """
 
     def __init__(
         self,
         parttype,
         mandatoryparams=(),
         advisoryparams=(),
         data=b'',
         mandatory=True,
     ):
         validateparttype(parttype)
         self.id = None
         self.type = parttype
         self._data = data
         self._mandatoryparams = list(mandatoryparams)
         self._advisoryparams = list(advisoryparams)
         # checking for duplicated entries
         self._seenparams = set()
         for pname, __ in self._mandatoryparams + self._advisoryparams:
             if pname in self._seenparams:
                 raise error.ProgrammingError(b'duplicated params: %s' % pname)
             self._seenparams.add(pname)
         # status of the part's generation:
         # - None: not started,
         # - False: currently generated,
         # - True: generation done.
         self._generated = None
         self.mandatory = mandatory
 
     def __repr__(self):
         cls = "%s.%s" % (self.__class__.__module__, self.__class__.__name__)
         return '<%s object at %x; id: %s; type: %s; mandatory: %s>' % (
             cls,
             id(self),
             self.id,
             self.type,
             self.mandatory,
         )
 
     def copy(self):
         """return a copy of the part
 
         The new part have the very same content but no partid assigned yet.
         Parts with generated data cannot be copied."""
         assert not hasattr(self.data, 'next')
         return self.__class__(
             self.type,
             self._mandatoryparams,
             self._advisoryparams,
             self._data,
             self.mandatory,
         )
 
     # methods used to defines the part content
     @property
     def data(self):
         return self._data
 
     @data.setter
     def data(self, data):
         if self._generated is not None:
             raise error.ReadOnlyPartError(b'part is being generated')
         self._data = data
 
     @property
     def mandatoryparams(self):
         # make it an immutable tuple to force people through ``addparam``
         return tuple(self._mandatoryparams)
 
     @property
     def advisoryparams(self):
         # make it an immutable tuple to force people through ``addparam``
         return tuple(self._advisoryparams)
 
     def addparam(self, name, value=b'', mandatory=True):
         """add a parameter to the part
 
         If 'mandatory' is set to True, the remote handler must claim support
         for this parameter or the unbundling will be aborted.
 
         The 'name' and 'value' cannot exceed 255 bytes each.
         """
         if self._generated is not None:
             raise error.ReadOnlyPartError(b'part is being generated')
         if name in self._seenparams:
             raise ValueError(b'duplicated params: %s' % name)
         self._seenparams.add(name)
         params = self._advisoryparams
         if mandatory:
             params = self._mandatoryparams
         params.append((name, value))
 
     # methods used to generates the bundle2 stream
     def getchunks(self, ui):
         if self._generated is not None:
             raise error.ProgrammingError(b'part can only be consumed once')
         self._generated = False
 
         if ui.debugflag:
             msg = [b'bundle2-output-part: "%s"' % self.type]
             if not self.mandatory:
                 msg.append(b' (advisory)')
             nbmp = len(self.mandatoryparams)
             nbap = len(self.advisoryparams)
             if nbmp or nbap:
                 msg.append(b' (params:')
                 if nbmp:
                     msg.append(b' %i mandatory' % nbmp)
                 if nbap:
                     msg.append(b' %i advisory' % nbmp)
                 msg.append(b')')
             if not self.data:
                 msg.append(b' empty payload')
             elif hasattr(self.data, 'next') or hasattr(self.data, '__next__'):
                 msg.append(b' streamed payload')
             else:
                 msg.append(b' %i bytes payload' % len(self.data))
             msg.append(b'\n')
             ui.debug(b''.join(msg))
 
         #### header
         if self.mandatory:
             parttype = self.type.upper()
         else:
             parttype = self.type.lower()
         outdebug(ui, b'part %s: "%s"' % (pycompat.bytestr(self.id), parttype))
         ## parttype
         header = [
             _pack(_fparttypesize, len(parttype)),
             parttype,
             _pack(_fpartid, self.id),
         ]
         ## parameters
         # count
         manpar = self.mandatoryparams
         advpar = self.advisoryparams
         header.append(_pack(_fpartparamcount, len(manpar), len(advpar)))
         # size
         parsizes = []
         for key, value in manpar:
             parsizes.append(len(key))
             parsizes.append(len(value))
         for key, value in advpar:
             parsizes.append(len(key))
             parsizes.append(len(value))
         paramsizes = _pack(_makefpartparamsizes(len(parsizes) // 2), *parsizes)
         header.append(paramsizes)
         # key, value
         for key, value in manpar:
             header.append(key)
             header.append(value)
         for key, value in advpar:
             header.append(key)
             header.append(value)
         ## finalize header
         try:
             headerchunk = b''.join(header)
         except TypeError:
             raise TypeError(
                 'Found a non-bytes trying to '
                 'build bundle part header: %r' % header
             )
         outdebug(ui, b'header chunk size: %i' % len(headerchunk))
         yield _pack(_fpartheadersize, len(headerchunk))
         yield headerchunk
         ## payload
         try:
             for chunk in self._payloadchunks():
                 outdebug(ui, b'payload chunk size: %i' % len(chunk))
                 yield _pack(_fpayloadsize, len(chunk))
                 yield chunk
         except GeneratorExit:
             # GeneratorExit means that nobody is listening for our
             # results anyway, so just bail quickly rather than trying
             # to produce an error part.
             ui.debug(b'bundle2-generatorexit\n')
             raise
         except BaseException as exc:
             bexc = stringutil.forcebytestr(exc)
             # backup exception data for later
             ui.debug(
                 b'bundle2-input-stream-interrupt: encoding exception %s' % bexc
             )
             tb = sys.exc_info()[2]
             msg = b'unexpected error: %s' % bexc
             interpart = bundlepart(
                 b'error:abort', [(b'message', msg)], mandatory=False
             )
             interpart.id = 0
             yield _pack(_fpayloadsize, -1)
             for chunk in interpart.getchunks(ui=ui):
                 yield chunk
             outdebug(ui, b'closing payload chunk')
             # abort current part payload
             yield _pack(_fpayloadsize, 0)
             pycompat.raisewithtb(exc, tb)
         # end of payload
         outdebug(ui, b'closing payload chunk')
         yield _pack(_fpayloadsize, 0)
         self._generated = True
 
     def _payloadchunks(self):
         """yield chunks of a the part payload
 
         Exists to handle the different methods to provide data to a part."""
         # we only support fixed size data now.
         # This will be improved in the future.
         if hasattr(self.data, 'next') or hasattr(self.data, '__next__'):
             buff = util.chunkbuffer(self.data)
             chunk = buff.read(preferedchunksize)
             while chunk:
                 yield chunk
                 chunk = buff.read(preferedchunksize)
         elif len(self.data):
             yield self.data
 
 
 flaginterrupt = -1
 
 
 class interrupthandler(unpackermixin):
     """read one part and process it with restricted capability
 
     This allows to transmit exception raised on the producer size during part
     iteration while the consumer is reading a part.
 
     Part processed in this manner only have access to a ui object,"""
 
     def __init__(self, ui, fp):
         super(interrupthandler, self).__init__(fp)
         self.ui = ui
 
     def _readpartheader(self):
         """reads a part header size and return the bytes blob
 
         returns None if empty"""
         headersize = self._unpack(_fpartheadersize)[0]
         if headersize < 0:
             raise error.BundleValueError(
                 b'negative part header size: %i' % headersize
             )
         indebug(self.ui, b'part header size: %i\n' % headersize)
         if headersize:
             return self._readexact(headersize)
         return None
 
     def __call__(self):
         self.ui.debug(
             b'bundle2-input-stream-interrupt: opening out of band context\n'
         )
         indebug(self.ui, b'bundle2 stream interruption, looking for a part.')
         headerblock = self._readpartheader()
         if headerblock is None:
             indebug(self.ui, b'no part found during interruption.')
             return
         part = unbundlepart(self.ui, headerblock, self._fp)
         op = interruptoperation(self.ui)
         hardabort = False
         try:
             _processpart(op, part)
         except (SystemExit, KeyboardInterrupt):
             hardabort = True
             raise
         finally:
             if not hardabort:
                 part.consume()
         self.ui.debug(
             b'bundle2-input-stream-interrupt: closing out of band context\n'
         )
 
 
 class interruptoperation:
     """A limited operation to be use by part handler during interruption
 
     It only have access to an ui object.
     """
 
     def __init__(self, ui):
         self.ui = ui
         self.reply = None
         self.captureoutput = False
 
     @property
     def repo(self):
         raise error.ProgrammingError(b'no repo access from stream interruption')
 
     def gettransaction(self):
         raise TransactionUnavailable(b'no repo access from stream interruption')
 
 
 def decodepayloadchunks(ui, fh):
     """Reads bundle2 part payload data into chunks.
 
     Part payload data consists of framed chunks. This function takes
     a file handle and emits those chunks.
     """
     dolog = ui.configbool(b'devel', b'bundle2.debug')
     debug = ui.debug
 
     headerstruct = struct.Struct(_fpayloadsize)
     headersize = headerstruct.size
     unpack = headerstruct.unpack
 
     readexactly = changegroup.readexactly
     read = fh.read
 
     chunksize = unpack(readexactly(fh, headersize))[0]
     indebug(ui, b'payload chunk size: %i' % chunksize)
 
     # changegroup.readexactly() is inlined below for performance.
     while chunksize:
         if chunksize >= 0:
             s = read(chunksize)
             if len(s) < chunksize:
                 raise error.Abort(
                     _(
                         b'stream ended unexpectedly '
                         b' (got %d bytes, expected %d)'
                     )
                     % (len(s), chunksize)
                 )
 
             yield s
         elif chunksize == flaginterrupt:
             # Interrupt "signal" detected. The regular stream is interrupted
             # and a bundle2 part follows. Consume it.
             interrupthandler(ui, fh)()
         else:
             raise error.BundleValueError(
                 b'negative payload chunk size: %s' % chunksize
             )
 
         s = read(headersize)
         if len(s) < headersize:
             raise error.Abort(
                 _(b'stream ended unexpectedly  (got %d bytes, expected %d)')
                 % (len(s), chunksize)
             )
 
         chunksize = unpack(s)[0]
 
         # indebug() inlined for performance.
         if dolog:
             debug(b'bundle2-input: payload chunk size: %i\n' % chunksize)
 
 
 class unbundlepart(unpackermixin):
     """a bundle part read from a bundle"""
 
     def __init__(self, ui, header, fp):
         super(unbundlepart, self).__init__(fp)
         self._seekable = hasattr(fp, 'seek') and hasattr(fp, 'tell')
         self.ui = ui
         # unbundle state attr
         self._headerdata = header
         self._headeroffset = 0
         self._initialized = False
         self.consumed = False
         # part data
         self.id = None
         self.type = None
         self.mandatoryparams = None
         self.advisoryparams = None
         self.params = None
         self.mandatorykeys = ()
         self._readheader()
         self._mandatory = None
         self._pos = 0
 
     def _fromheader(self, size):
         """return the next <size> byte from the header"""
         offset = self._headeroffset
         data = self._headerdata[offset : (offset + size)]
         self._headeroffset = offset + size
         return data
 
     def _unpackheader(self, format):
         """read given format from header
 
         This automatically compute the size of the format to read."""
         data = self._fromheader(struct.calcsize(format))
         return _unpack(format, data)
 
     def _initparams(self, mandatoryparams, advisoryparams):
         """internal function to setup all logic related parameters"""
         # make it read only to prevent people touching it by mistake.
         self.mandatoryparams = tuple(mandatoryparams)
         self.advisoryparams = tuple(advisoryparams)
         # user friendly UI
         self.params = util.sortdict(self.mandatoryparams)
         self.params.update(self.advisoryparams)
         self.mandatorykeys = frozenset(p[0] for p in mandatoryparams)
 
     def _readheader(self):
         """read the header and setup the object"""
         typesize = self._unpackheader(_fparttypesize)[0]
         self.type = self._fromheader(typesize)
         indebug(self.ui, b'part type: "%s"' % self.type)
         self.id = self._unpackheader(_fpartid)[0]
         indebug(self.ui, b'part id: "%s"' % pycompat.bytestr(self.id))
         # extract mandatory bit from type
         self.mandatory = self.type != self.type.lower()
         self.type = self.type.lower()
         ## reading parameters
         # param count
         mancount, advcount = self._unpackheader(_fpartparamcount)
         indebug(self.ui, b'part parameters: %i' % (mancount + advcount))
         # param size
         fparamsizes = _makefpartparamsizes(mancount + advcount)
         paramsizes = self._unpackheader(fparamsizes)
         # make it a list of couple again
         paramsizes = list(zip(paramsizes[::2], paramsizes[1::2]))
         # split mandatory from advisory
         mansizes = paramsizes[:mancount]
         advsizes = paramsizes[mancount:]
         # retrieve param value
         manparams = []
         for key, value in mansizes:
             manparams.append((self._fromheader(key), self._fromheader(value)))
         advparams = []
         for key, value in advsizes:
             advparams.append((self._fromheader(key), self._fromheader(value)))
         self._initparams(manparams, advparams)
         ## part payload
         self._payloadstream = util.chunkbuffer(self._payloadchunks())
         # we read the data, tell it
         self._initialized = True
 
     def _payloadchunks(self):
         """Generator of decoded chunks in the payload."""
         return decodepayloadchunks(self.ui, self._fp)
 
     def consume(self):
         """Read the part payload until completion.
 
         By consuming the part data, the underlying stream read offset will
         be advanced to the next part (or end of stream).
         """
         if self.consumed:
             return
 
         chunk = self.read(32768)
         while chunk:
             self._pos += len(chunk)
             chunk = self.read(32768)
 
     def read(self, size=None):
         """read payload data"""
         if not self._initialized:
             self._readheader()
         if size is None:
             data = self._payloadstream.read()
         else:
             data = self._payloadstream.read(size)
         self._pos += len(data)
         if size is None or len(data) < size:
             if not self.consumed and self._pos:
                 self.ui.debug(
                     b'bundle2-input-part: total payload size %i\n' % self._pos
                 )
             self.consumed = True
         return data
 
 
 class seekableunbundlepart(unbundlepart):
     """A bundle2 part in a bundle that is seekable.
 
     Regular ``unbundlepart`` instances can only be read once. This class
     extends ``unbundlepart`` to enable bi-directional seeking within the
     part.
 
     Bundle2 part data consists of framed chunks. Offsets when seeking
     refer to the decoded data, not the offsets in the underlying bundle2
     stream.
 
     To facilitate quickly seeking within the decoded data, instances of this
     class maintain a mapping between offsets in the underlying stream and
     the decoded payload. This mapping will consume memory in proportion
     to the number of chunks within the payload (which almost certainly
     increases in proportion with the size of the part).
     """
 
     def __init__(self, ui, header, fp):
         # (payload, file) offsets for chunk starts.
         self._chunkindex = []
 
         super(seekableunbundlepart, self).__init__(ui, header, fp)
 
     def _payloadchunks(self, chunknum=0):
         '''seek to specified chunk and start yielding data'''
         if len(self._chunkindex) == 0:
             assert chunknum == 0, b'Must start with chunk 0'
             self._chunkindex.append((0, self._tellfp()))
         else:
             assert chunknum < len(self._chunkindex), (
                 b'Unknown chunk %d' % chunknum
             )
             self._seekfp(self._chunkindex[chunknum][1])
 
         pos = self._chunkindex[chunknum][0]
 
         for chunk in decodepayloadchunks(self.ui, self._fp):
             chunknum += 1
             pos += len(chunk)
             if chunknum == len(self._chunkindex):
                 self._chunkindex.append((pos, self._tellfp()))
 
             yield chunk
 
     def _findchunk(self, pos):
         '''for a given payload position, return a chunk number and offset'''
         for chunk, (ppos, fpos) in enumerate(self._chunkindex):
             if ppos == pos:
                 return chunk, 0
             elif ppos > pos:
                 return chunk - 1, pos - self._chunkindex[chunk - 1][0]
         raise ValueError(b'Unknown chunk')
 
     def tell(self):
         return self._pos
 
     def seek(self, offset, whence=os.SEEK_SET):
         if whence == os.SEEK_SET:
             newpos = offset
         elif whence == os.SEEK_CUR:
             newpos = self._pos + offset
         elif whence == os.SEEK_END:
             if not self.consumed:
                 # Can't use self.consume() here because it advances self._pos.
                 chunk = self.read(32768)
                 while chunk:
                     chunk = self.read(32768)
             newpos = self._chunkindex[-1][0] - offset
         else:
             raise ValueError(b'Unknown whence value: %r' % (whence,))
 
         if newpos > self._chunkindex[-1][0] and not self.consumed:
             # Can't use self.consume() here because it advances self._pos.
             chunk = self.read(32768)
             while chunk:
                 chunk = self.read(32668)
 
         if not 0 <= newpos <= self._chunkindex[-1][0]:
             raise ValueError(b'Offset out of range')
 
         if self._pos != newpos:
             chunk, internaloffset = self._findchunk(newpos)
             self._payloadstream = util.chunkbuffer(self._payloadchunks(chunk))
             adjust = self.read(internaloffset)
             if len(adjust) != internaloffset:
                 raise error.Abort(_(b'Seek failed\n'))
             self._pos = newpos
 
     def _seekfp(self, offset, whence=0):
         """move the underlying file pointer
 
         This method is meant for internal usage by the bundle2 protocol only.
         They directly manipulate the low level stream including bundle2 level
         instruction.
 
         Do not use it to implement higher-level logic or methods."""
         if self._seekable:
             return self._fp.seek(offset, whence)
         else:
             raise NotImplementedError(_(b'File pointer is not seekable'))
 
     def _tellfp(self):
         """return the file offset, or None if file is not seekable
 
         This method is meant for internal usage by the bundle2 protocol only.
         They directly manipulate the low level stream including bundle2 level
         instruction.
 
         Do not use it to implement higher-level logic or methods."""
         if self._seekable:
             try:
                 return self._fp.tell()
             except IOError as e:
                 if e.errno == errno.ESPIPE:
                     self._seekable = False
                 else:
                     raise
         return None
 
 
 # These are only the static capabilities.
 # Check the 'getrepocaps' function for the rest.
 capabilities: "Capabilities" = {
     b'HG20': (),
     b'bookmarks': (),
     b'error': (b'abort', b'unsupportedcontent', b'pushraced', b'pushkey'),
     b'listkeys': (),
     b'pushkey': (),
     b'digests': tuple(sorted(util.DIGESTS.keys())),
     b'remote-changegroup': (b'http', b'https'),
     b'hgtagsfnodes': (),
     b'phases': (b'heads',),
     b'stream': (b'v2',),
 }
 
 
 # TODO: drop the default value for 'role'
 def getrepocaps(repo, allowpushback: bool = False, role=None) -> "Capabilities":
     """return the bundle2 capabilities for a given repo
 
     Exists to allow extensions (like evolution) to mutate the capabilities.
 
     The returned value is used for servers advertising their capabilities as
     well as clients advertising their capabilities to servers as part of
     bundle2 requests. The ``role`` argument specifies which is which.
     """
     if role not in (b'client', b'server'):
         raise error.ProgrammingError(b'role argument must be client or server')
 
     caps = capabilities.copy()
     caps[b'changegroup'] = tuple(
         sorted(changegroup.supportedincomingversions(repo))
     )
     if obsolete.isenabled(repo, obsolete.exchangeopt):
         supportedformat = tuple(b'V%i' % v for v in obsolete.formats)
         caps[b'obsmarkers'] = supportedformat
     if allowpushback:
         caps[b'pushback'] = ()
     cpmode = repo.ui.config(b'server', b'concurrent-push-mode')
     if cpmode == b'check-related':
         caps[b'checkheads'] = (b'related',)
     if b'phases' in repo.ui.configlist(b'devel', b'legacy.exchange'):
         caps.pop(b'phases')
 
     # Don't advertise stream clone support in server mode if not configured.
     if role == b'server':
         streamsupported = repo.ui.configbool(
             b'server', b'uncompressed', untrusted=True
         )
         featuresupported = repo.ui.configbool(b'server', b'bundle2.stream')
 
         if not streamsupported or not featuresupported:
             caps.pop(b'stream')
     # Else always advertise support on client, because payload support
     # should always be advertised.
 
     if repo.ui.configbool(b'experimental', b'stream-v3'):
         if b'stream' in caps:
             caps[b'stream'] += (b'v3-exp',)
 
     # b'rev-branch-cache is no longer advertised, but still supported
     # for legacy clients.
 
     return caps
 
 
 def bundle2caps(remote) -> "Capabilities":
     """return the bundle capabilities of a peer as dict"""
     raw = remote.capable(b'bundle2')
     if not raw and raw != b'':
         return {}
     capsblob = urlreq.unquote(remote.capable(b'bundle2'))
     return decodecaps(capsblob)
 
 
 def obsmarkersversion(caps: "Capabilities"):
     """extract the list of supported obsmarkers versions from a bundle2caps dict"""
     obscaps = caps.get(b'obsmarkers', ())
     return [int(c[1:]) for c in obscaps if c.startswith(b'V')]
 
 
 def writenewbundle(
     ui,
     repo,
     source,
     filename,
     bundletype,
     outgoing,
     opts,
     vfs=None,
     compression=None,
     compopts=None,
     allow_internal=False,
 ):
     if bundletype.startswith(b'HG10'):
         cg = changegroup.makechangegroup(repo, outgoing, b'01', source)
         return writebundle(
             ui,
             cg,
             filename,
             bundletype,
             vfs=vfs,
             compression=compression,
             compopts=compopts,
         )
     elif not bundletype.startswith(b'HG20'):
         raise error.ProgrammingError(b'unknown bundle type: %s' % bundletype)
 
     # enforce that no internal phase are to be bundled
     bundled_internal = repo.revs(b"%ln and _internal()", outgoing.ancestorsof)
     if bundled_internal and not allow_internal:
         count = len(repo.revs(b'%ln and _internal()', outgoing.missing))
         msg = "backup bundle would contains %d internal changesets"
         msg %= count
         raise error.ProgrammingError(msg)
 
     caps: "Capabilities" = {}
     if opts.get(b'obsolescence', False):
         caps[b'obsmarkers'] = (b'V1',)
     stream_version = opts.get(b'stream', b"")
     if stream_version == b"v2":
         caps[b'stream'] = [b'v2']
     elif stream_version == b"v3-exp":
         caps[b'stream'] = [b'v3-exp']
     bundle = bundle20(ui, caps)
     bundle.setcompression(compression, compopts)
     _addpartsfromopts(ui, repo, bundle, source, outgoing, opts)
     chunkiter = bundle.getchunks()
 
     return changegroup.writechunks(ui, chunkiter, filename, vfs=vfs)
 
 
 def _addpartsfromopts(ui, repo, bundler, source, outgoing, opts):
     # We should eventually reconcile this logic with the one behind
     # 'exchange.getbundle2partsgenerator'.
     #
     # The type of input from 'getbundle' and 'writenewbundle' are a bit
     # different right now. So we keep them separated for now for the sake of
     # simplicity.
 
     # we might not always want a changegroup in such bundle, for example in
     # stream bundles
     if opts.get(b'changegroup', True):
         cgversion = opts.get(b'cg.version')
         if cgversion is None:
             cgversion = changegroup.safeversion(repo)
         cg = changegroup.makechangegroup(repo, outgoing, cgversion, source)
         part = bundler.newpart(b'changegroup', data=cg.getchunks())
         part.addparam(b'version', cg.version)
         if b'clcount' in cg.extras:
             part.addparam(
                 b'nbchanges', b'%d' % cg.extras[b'clcount'], mandatory=False
             )
         if opts.get(b'phases'):
             target_phase = phases.draft
             for head in outgoing.ancestorsof:
                 target_phase = max(target_phase, repo[head].phase())
             if target_phase > phases.draft:
                 part.addparam(
                     b'targetphase',
                     b'%d' % target_phase,
                     mandatory=False,
                 )
     if repository.REPO_FEATURE_SIDE_DATA in repo.features:
         part.addparam(b'exp-sidedata', b'1')
 
     if opts.get(b'stream', b"") == b"v2":
         addpartbundlestream2(bundler, repo, stream=True)
 
     if opts.get(b'stream', b"") == b"v3-exp":
         addpartbundlestream2(bundler, repo, stream=True)
 
     if opts.get(b'tagsfnodescache', True):
         addparttagsfnodescache(repo, bundler, outgoing)
 
     if opts.get(b'revbranchcache', True):
         addpartrevbranchcache(repo, bundler, outgoing)
 
     if opts.get(b'obsolescence', False):
-        obsmarkers = repo.obsstore.relevantmarkers(outgoing.missing)
+        obsmarkers = repo.obsstore.relevantmarkers(nodes=outgoing.missing)
         buildobsmarkerspart(
             bundler,
             obsmarkers,
             mandatory=opts.get(b'obsolescence-mandatory', True),
         )
 
     if opts.get(b'phases', False):
         headsbyphase = phases.subsetphaseheads(repo, outgoing.missing)
         phasedata = phases.binaryencode(headsbyphase)
         bundler.newpart(b'phase-heads', data=phasedata)
 
 
 def addparttagsfnodescache(repo, bundler, outgoing):
     # we include the tags fnode cache for the bundle changeset
     # (as an optional parts)
     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.ancestorsof:
         # Don't compute missing, as this may slow down serving.
         fnode = cache.getfnode(node, computemissing=False)
         if fnode:
             chunks.extend([node, fnode])
 
     if chunks:
         bundler.newpart(
             b'hgtagsfnodes',
             mandatory=False,
             data=b''.join(chunks),
         )
 
 
 def addpartrevbranchcache(repo, bundler, outgoing):
     # we include the rev branch cache for the bundle changeset
     # (as an optional parts)
     cache = repo.revbranchcache()
     cl = repo.unfiltered().changelog
     branchesdata = collections.defaultdict(lambda: (set(), set()))
     for node in outgoing.missing:
         branch, close = cache.branchinfo(cl.rev(node))
         branchesdata[branch][close].add(node)
 
     def generate():
         for branch, (nodes, closed) in sorted(branchesdata.items()):
             utf8branch = encoding.fromlocal(branch)
             yield rbcstruct.pack(len(utf8branch), len(nodes), len(closed))
             yield utf8branch
             for n in sorted(nodes):
                 yield n
             for n in sorted(closed):
                 yield n
 
     bundler.newpart(b'cache:rev-branch-cache', data=generate(), mandatory=False)
 
 
 def _formatrequirementsspec(requirements):
     requirements = [req for req in requirements if req != b"shared"]
     return urlreq.quote(b','.join(sorted(requirements)))
 
 
 def _formatrequirementsparams(requirements):
     requirements = _formatrequirementsspec(requirements)
     params = b"%s%s" % (urlreq.quote(b"requirements="), requirements)
     return params
 
 
 def format_remote_wanted_sidedata(repo):
     """Formats a repo's wanted sidedata categories into a bytestring for
     capabilities exchange."""
     wanted = b""
     if repo._wanted_sidedata:
         wanted = b','.join(
             pycompat.bytestr(c) for c in sorted(repo._wanted_sidedata)
         )
     return wanted
 
 
 def read_remote_wanted_sidedata(remote):
     sidedata_categories = remote.capable(b'exp-wanted-sidedata')
     return read_wanted_sidedata(sidedata_categories)
 
 
 def read_wanted_sidedata(formatted):
     if formatted:
         return set(formatted.split(b','))
     return set()
 
 
 def addpartbundlestream2(bundler, repo, **kwargs):
     if not kwargs.get('stream', False):
         return
 
     if not streamclone.allowservergeneration(repo):
         msg = _(b'stream data requested but server does not allow this feature')
         hint = _(b'the client seems buggy')
         raise error.Abort(msg, hint=hint)
     if not (b'stream' in bundler.capabilities):
         msg = _(
             b'stream data requested but supported streaming clone versions were not specified'
         )
         hint = _(b'the client seems buggy')
         raise error.Abort(msg, hint=hint)
     client_supported = set(bundler.capabilities[b'stream'])
     server_supported = set(getrepocaps(repo, role=b'client').get(b'stream', []))
     common_supported = client_supported & server_supported
     if not common_supported:
         msg = _(b'no common supported version with the client: %s; %s')
         str_server = b','.join(sorted(server_supported))
         str_client = b','.join(sorted(client_supported))
         msg %= (str_server, str_client)
         raise error.Abort(msg)
     version = max(common_supported)
 
     # Stream clones don't compress well. And compression undermines a
     # goal of stream clones, which is to be fast. Communicate the desire
     # to avoid compression to consumers of the bundle.
     bundler.prefercompressed = False
 
     # get the includes and excludes
     includepats = kwargs.get('includepats')
     excludepats = kwargs.get('excludepats')
 
     narrowstream = repo.ui.configbool(
         b'experimental', b'server.stream-narrow-clones'
     )
 
     if (includepats or excludepats) and not narrowstream:
         raise error.Abort(_(b'server does not support narrow stream clones'))
 
     includeobsmarkers = False
     if repo.obsstore:
         remoteversions = obsmarkersversion(bundler.capabilities)
         if not remoteversions:
             raise error.Abort(
                 _(
                     b'server has obsolescence markers, but client '
                     b'cannot receive them via stream clone'
                 )
             )
         elif repo.obsstore._version in remoteversions:
             includeobsmarkers = True
 
     if version == b"v2":
         filecount, bytecount, it = streamclone.generatev2(
             repo, includepats, excludepats, includeobsmarkers
         )
         requirements = streamclone.streamed_requirements(repo)
         requirements = _formatrequirementsspec(requirements)
         part = bundler.newpart(b'stream2', data=it)
         part.addparam(b'bytecount', b'%d' % bytecount, mandatory=True)
         part.addparam(b'filecount', b'%d' % filecount, mandatory=True)
         part.addparam(b'requirements', requirements, mandatory=True)
     elif version == b"v3-exp":
         it = streamclone.generatev3(
             repo, includepats, excludepats, includeobsmarkers
         )
         requirements = streamclone.streamed_requirements(repo)
         requirements = _formatrequirementsspec(requirements)
         part = bundler.newpart(b'stream3-exp', data=it)
         part.addparam(b'requirements', requirements, mandatory=True)
 
 
 def buildobsmarkerspart(bundler, markers, mandatory=True):
     """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 not markers:
         return None
 
     remoteversions = obsmarkersversion(bundler.capabilities)
     version = obsolete.commonversion(remoteversions)
     if version is None:
         raise ValueError(b'bundler does not support common obsmarker format')
     stream = obsolete.encodemarkers(markers, True, version=version)
     return bundler.newpart(b'obsmarkers', data=stream, mandatory=mandatory)
 
 
 def writebundle(
     ui, cg, filename, bundletype, vfs=None, compression=None, compopts=None
 ):
     """Write a bundle file and return its filename.
 
     Existing files will not be overwritten.
     If no filename is specified, a temporary file is created.
     bz2 compression can be turned off.
     The bundle file will be deleted in case of errors.
     """
 
     if bundletype == b"HG20":
         bundle = bundle20(ui)
         bundle.setcompression(compression, compopts)
         part = bundle.newpart(b'changegroup', data=cg.getchunks())
         part.addparam(b'version', cg.version)
         if b'clcount' in cg.extras:
             part.addparam(
                 b'nbchanges', b'%d' % cg.extras[b'clcount'], mandatory=False
             )
         chunkiter = bundle.getchunks()
     else:
         # compression argument is only for the bundle2 case
         assert compression is None
         if cg.version != b'01':
             raise error.Abort(
                 _(b'old bundle types only supports v1 changegroups')
             )
 
         # HG20 is the case without 2 values to unpack, but is handled above.
         # pytype: disable=bad-unpacking
         header, comp = bundletypes[bundletype]
         # pytype: enable=bad-unpacking
 
         if comp not in util.compengines.supportedbundletypes:
             raise error.Abort(_(b'unknown stream compression type: %s') % comp)
         compengine = util.compengines.forbundletype(comp)
 
         def chunkiter():
             yield header
             for chunk in compengine.compressstream(cg.getchunks(), compopts):
                 yield chunk
 
         chunkiter = chunkiter()
 
     # parse the changegroup data, otherwise we will block
     # in case of sshrepo because we don't know the end of the stream
     return changegroup.writechunks(ui, chunkiter, filename, vfs=vfs)
 
 
 def combinechangegroupresults(op):
     """logic to combine 0 or more addchangegroup results into one"""
     results = [r.get(b'return', 0) for r in op.records[b'changegroup']]
     changedheads = 0
     result = 1
     for ret in results:
         # If any changegroup result is 0, return 0
         if ret == 0:
             result = 0
             break
         if ret < -1:
             changedheads += ret + 1
         elif ret > 1:
             changedheads += ret - 1
     if changedheads > 0:
         result = 1 + changedheads
     elif changedheads < 0:
         result = -1 + changedheads
     return result
 
 
 @parthandler(
     b'changegroup',
     (
         b'version',
         b'nbchanges',
         b'exp-sidedata',
         b'exp-wanted-sidedata',
         b'treemanifest',
         b'targetphase',
     ),
 )
 def handlechangegroup(op, inpart):
     """apply a changegroup part on the repo"""
     from . import localrepo
 
     tr = op.gettransaction()
     unpackerversion = inpart.params.get(b'version', b'01')
     # We should raise an appropriate exception here
     cg = changegroup.getunbundler(unpackerversion, inpart, None)
     # the source and url passed here are overwritten by the one contained in
     # the transaction.hookargs argument. So 'bundle2' is a placeholder
     nbchangesets = None
     if b'nbchanges' in inpart.params:
         nbchangesets = int(inpart.params.get(b'nbchanges'))
     if b'treemanifest' in inpart.params and not scmutil.istreemanifest(op.repo):
         if len(op.repo.changelog) != 0:
             raise error.Abort(
                 _(
                     b"bundle contains tree manifests, but local repo is "
                     b"non-empty and does not use tree manifests"
                 )
             )
         op.repo.requirements.add(requirements.TREEMANIFEST_REQUIREMENT)
         op.repo.svfs.options = localrepo.resolvestorevfsoptions(
             op.repo.ui, op.repo.requirements, op.repo.features
         )
         scmutil.writereporequirements(op.repo)
 
     extrakwargs = {}
     targetphase = inpart.params.get(b'targetphase')
     if targetphase is not None:
         extrakwargs['targetphase'] = int(targetphase)
 
     remote_sidedata = inpart.params.get(b'exp-wanted-sidedata')
     extrakwargs['sidedata_categories'] = read_wanted_sidedata(remote_sidedata)
 
     ret = _processchangegroup(
         op,
         cg,
         tr,
         op.source,
         b'bundle2',
         expectedtotal=nbchangesets,
         **extrakwargs,
     )
     if op.reply is not None:
         # This is definitely not the final form of this
         # return. But one need to start somewhere.
         part = op.reply.newpart(b'reply:changegroup', mandatory=False)
         part.addparam(
             b'in-reply-to', pycompat.bytestr(inpart.id), mandatory=False
         )
         part.addparam(b'return', b'%i' % ret, mandatory=False)
     assert not inpart.read()
 
 
 _remotechangegroupparams = tuple(
     [b'url', b'size', b'digests']
     + [b'digest:%s' % k for k in util.DIGESTS.keys()]
 )
 
 
 @parthandler(b'remote-changegroup', _remotechangegroupparams)
 def handleremotechangegroup(op, inpart):
     """apply a bundle10 on the repo, given an url and validation information
 
     All the information about the remote bundle to import are given as
     parameters. The parameters include:
       - url: the url to the bundle10.
       - size: the bundle10 file size. It is used to validate what was
         retrieved by the client matches the server knowledge about the bundle.
       - digests: a space separated list of the digest types provided as
         parameters.
       - digest:<digest-type>: the hexadecimal representation of the digest with
         that name. Like the size, it is used to validate what was retrieved by
         the client matches what the server knows about the bundle.
 
     When multiple digest types are given, all of them are checked.
     """
     try:
         raw_url = inpart.params[b'url']
     except KeyError:
         raise error.Abort(_(b'remote-changegroup: missing "%s" param') % b'url')
     parsed_url = urlutil.url(raw_url)
     if parsed_url.scheme not in capabilities[b'remote-changegroup']:
         raise error.Abort(
             _(b'remote-changegroup does not support %s urls')
             % parsed_url.scheme
         )
 
     try:
         size = int(inpart.params[b'size'])
     except ValueError:
         raise error.Abort(
             _(b'remote-changegroup: invalid value for param "%s"') % b'size'
         )
     except KeyError:
         raise error.Abort(
             _(b'remote-changegroup: missing "%s" param') % b'size'
         )
 
     digests = {}
     for typ in inpart.params.get(b'digests', b'').split():
         param = b'digest:%s' % typ
         try:
             value = inpart.params[param]
         except KeyError:
             raise error.Abort(
                 _(b'remote-changegroup: missing "%s" param') % param
             )
         digests[typ] = value
 
     real_part = util.digestchecker(url.open(op.ui, raw_url), size, digests)
 
     tr = op.gettransaction()
     from . import exchange
 
     cg = exchange.readbundle(op.repo.ui, real_part, raw_url)
     if not isinstance(cg, changegroup.cg1unpacker):
         raise error.Abort(
             _(b'%s: not a bundle version 1.0') % urlutil.hidepassword(raw_url)
         )
     ret = _processchangegroup(op, cg, tr, op.source, b'bundle2')
     if op.reply is not None:
         # This is definitely not the final form of this
         # return. But one need to start somewhere.
         part = op.reply.newpart(b'reply:changegroup')
         part.addparam(
             b'in-reply-to', pycompat.bytestr(inpart.id), mandatory=False
         )
         part.addparam(b'return', b'%i' % ret, mandatory=False)
     try:
         real_part.validate()
     except error.Abort as e:
         raise error.Abort(
             _(b'bundle at %s is corrupted:\n%s')
             % (urlutil.hidepassword(raw_url), e.message)
         )
     assert not inpart.read()
 
 
 @parthandler(b'reply:changegroup', (b'return', b'in-reply-to'))
 def handlereplychangegroup(op, inpart):
     ret = int(inpart.params[b'return'])
     replyto = int(inpart.params[b'in-reply-to'])
     op.records.add(b'changegroup', {b'return': ret}, replyto)
 
 
 @parthandler(b'check:bookmarks')
 def handlecheckbookmarks(op, inpart):
     """check location of bookmarks
 
     This part is to be used to detect push race regarding bookmark, it
     contains binary encoded (bookmark, node) tuple. If the local state does
     not marks the one in the part, a PushRaced exception is raised
     """
     bookdata = bookmarks.binarydecode(op.repo, inpart)
 
     msgstandard = (
         b'remote repository changed while pushing - please try again '
         b'(bookmark "%s" move from %s to %s)'
     )
     msgmissing = (
         b'remote repository changed while pushing - please try again '
         b'(bookmark "%s" is missing, expected %s)'
     )
     msgexist = (
         b'remote repository changed while pushing - please try again '
         b'(bookmark "%s" set on %s, expected missing)'
     )
     for book, node in bookdata:
         currentnode = op.repo._bookmarks.get(book)
         if currentnode != node:
             if node is None:
                 finalmsg = msgexist % (book, short(currentnode))
             elif currentnode is None:
                 finalmsg = msgmissing % (book, short(node))
             else:
                 finalmsg = msgstandard % (
                     book,
                     short(node),
                     short(currentnode),
                 )
             raise error.PushRaced(finalmsg)
 
 
 @parthandler(b'check:heads')
 def handlecheckheads(op, inpart):
     """check that head of the repo did not change
 
     This is used to detect a push race when using unbundle.
     This replaces the "heads" argument of unbundle."""
     h = inpart.read(20)
     heads = []
     while len(h) == 20:
         heads.append(h)
         h = inpart.read(20)
     assert not h
     # Trigger a transaction so that we are guaranteed to have the lock now.
     if op.ui.configbool(b'experimental', b'bundle2lazylocking'):
         op.gettransaction()
     if sorted(heads) != sorted(op.repo.heads()):
         raise error.PushRaced(
             b'remote repository changed while pushing - please try again'
         )
 
 
 @parthandler(b'check:updated-heads')
 def handlecheckupdatedheads(op, inpart):
     """check for race on the heads touched by a push
 
     This is similar to 'check:heads' but focus on the heads actually updated
     during the push. If other activities happen on unrelated heads, it is
     ignored.
 
     This allow server with high traffic to avoid push contention as long as
     unrelated parts of the graph are involved."""
     h = inpart.read(20)
     heads = []
     while len(h) == 20:
         heads.append(h)
         h = inpart.read(20)
     assert not h
     # trigger a transaction so that we are guaranteed to have the lock now.
     if op.ui.configbool(b'experimental', b'bundle2lazylocking'):
         op.gettransaction()
 
     currentheads = set()
     for ls in op.repo.branchmap().iterheads():
         currentheads.update(ls)
 
     for h in heads:
         if h not in currentheads:
             raise error.PushRaced(
                 b'remote repository changed while pushing - '
                 b'please try again'
             )
 
 
 @parthandler(b'check:phases')
 def handlecheckphases(op, inpart):
     """check that phase boundaries of the repository did not change
 
     This is used to detect a push race.
     """
     phasetonodes = phases.binarydecode(inpart)
     unfi = op.repo.unfiltered()
     cl = unfi.changelog
     phasecache = unfi._phasecache
     msg = (
         b'remote repository changed while pushing - please try again '
         b'(%s is %s expected %s)'
     )
     for expectedphase, nodes in phasetonodes.items():
         for n in nodes:
             actualphase = phasecache.phase(unfi, cl.rev(n))
             if actualphase != expectedphase:
                 finalmsg = msg % (
                     short(n),
                     phases.phasenames[actualphase],
                     phases.phasenames[expectedphase],
                 )
                 raise error.PushRaced(finalmsg)
 
 
 @parthandler(b'output')
 def handleoutput(op, inpart):
     """forward output captured on the server to the client"""
     for line in inpart.read().splitlines():
         op.ui.status(_(b'remote: %s\n') % line)
 
 
 @parthandler(b'replycaps')
 def handlereplycaps(op, inpart):
     """Notify that a reply bundle should be created
 
     The payload contains the capabilities information for the reply"""
     caps = decodecaps(inpart.read())
     if op.reply is None:
         op.reply = bundle20(op.ui, caps)
 
 
 class AbortFromPart(error.Abort):
     """Sub-class of Abort that denotes an error from a bundle2 part."""
 
 
 @parthandler(b'error:abort', (b'message', b'hint'))
 def handleerrorabort(op, inpart):
     """Used to transmit abort error over the wire"""
     raise AbortFromPart(
         inpart.params[b'message'], hint=inpart.params.get(b'hint')
     )
 
 
 @parthandler(
     b'error:pushkey',
     (b'namespace', b'key', b'new', b'old', b'ret', b'in-reply-to'),
 )
 def handleerrorpushkey(op, inpart):
     """Used to transmit failure of a mandatory pushkey over the wire"""
     kwargs = {}
     for name in (b'namespace', b'key', b'new', b'old', b'ret'):
         value = inpart.params.get(name)
         if value is not None:
             kwargs[name] = value
     raise error.PushkeyFailed(
         inpart.params[b'in-reply-to'], **pycompat.strkwargs(kwargs)
     )
 
 
 @parthandler(b'error:unsupportedcontent', (b'parttype', b'params'))
 def handleerrorunsupportedcontent(op, inpart):
     """Used to transmit unknown content error over the wire"""
     kwargs = {}
     parttype = inpart.params.get(b'parttype')
     if parttype is not None:
         kwargs[b'parttype'] = parttype
     params = inpart.params.get(b'params')
     if params is not None:
         kwargs[b'params'] = params.split(b'\0')
 
     raise error.BundleUnknownFeatureError(**pycompat.strkwargs(kwargs))
 
 
 @parthandler(b'error:pushraced', (b'message',))
 def handleerrorpushraced(op, inpart):
     """Used to transmit push race error over the wire"""
     raise error.ResponseError(_(b'push failed:'), inpart.params[b'message'])
 
 
 @parthandler(b'listkeys', (b'namespace',))
 def handlelistkeys(op, inpart):
     """retrieve pushkey namespace content stored in a bundle2"""
     namespace = inpart.params[b'namespace']
     r = pushkey.decodekeys(inpart.read())
     op.records.add(b'listkeys', (namespace, r))
 
 
 @parthandler(b'pushkey', (b'namespace', b'key', b'old', b'new'))
 def handlepushkey(op, inpart):
     """process a pushkey request"""
     dec = pushkey.decode
     namespace = dec(inpart.params[b'namespace'])
     key = dec(inpart.params[b'key'])
     old = dec(inpart.params[b'old'])
     new = dec(inpart.params[b'new'])
     # Grab the transaction to ensure that we have the lock before performing the
     # pushkey.
     if op.ui.configbool(b'experimental', b'bundle2lazylocking'):
         op.gettransaction()
     ret = op.repo.pushkey(namespace, key, old, new)
     record = {b'namespace': namespace, b'key': key, b'old': old, b'new': new}
     op.records.add(b'pushkey', record)
     if op.reply is not None:
         rpart = op.reply.newpart(b'reply:pushkey')
         rpart.addparam(
             b'in-reply-to', pycompat.bytestr(inpart.id), mandatory=False
         )
         rpart.addparam(b'return', b'%i' % ret, mandatory=False)
     if inpart.mandatory and not ret:
         kwargs = {}
         for key in (b'namespace', b'key', b'new', b'old', b'ret'):
             if key in inpart.params:
                 kwargs[key] = inpart.params[key]
         raise error.PushkeyFailed(
             partid=b'%d' % inpart.id, **pycompat.strkwargs(kwargs)
         )
 
 
 @parthandler(b'bookmarks')
 def handlebookmark(op, inpart):
     """transmit bookmark information
 
     The part contains binary encoded bookmark information.
 
     The exact behavior of this part can be controlled by the 'bookmarks' mode
     on the bundle operation.
 
     When mode is 'apply' (the default) the bookmark information is applied as
     is to the unbundling repository. Make sure a 'check:bookmarks' part is
     issued earlier to check for push races in such update. This behavior is
     suitable for pushing.
 
     When mode is 'records', the information is recorded into the 'bookmarks'
     records of the bundle operation. This behavior is suitable for pulling.
     """
     changes = bookmarks.binarydecode(op.repo, inpart)
 
     pushkeycompat = op.repo.ui.configbool(
         b'server', b'bookmarks-pushkey-compat'
     )
     bookmarksmode = op.modes.get(b'bookmarks', b'apply')
 
     if bookmarksmode == b'apply':
         tr = op.gettransaction()
         bookstore = op.repo._bookmarks
         if pushkeycompat:
             allhooks = []
             for book, node in changes:
                 hookargs = tr.hookargs.copy()
                 hookargs[b'pushkeycompat'] = b'1'
                 hookargs[b'namespace'] = b'bookmarks'
                 hookargs[b'key'] = book
                 hookargs[b'old'] = hex(bookstore.get(book, b''))
                 hookargs[b'new'] = hex(node if node is not None else b'')
                 allhooks.append(hookargs)
 
             for hookargs in allhooks:
                 op.repo.hook(
                     b'prepushkey', throw=True, **pycompat.strkwargs(hookargs)
                 )
 
         for book, node in changes:
             if bookmarks.isdivergent(book):
                 msg = _(b'cannot accept divergent bookmark %s!') % book
                 raise error.Abort(msg)
 
         bookstore.applychanges(op.repo, op.gettransaction(), changes)
 
         if pushkeycompat:
 
             def runhook(unused_success):
                 for hookargs in allhooks:
                     op.repo.hook(b'pushkey', **pycompat.strkwargs(hookargs))
 
             op.repo._afterlock(runhook)
 
     elif bookmarksmode == b'records':
         for book, node in changes:
             record = {b'bookmark': book, b'node': node}
             op.records.add(b'bookmarks', record)
     else:
         raise error.ProgrammingError(
             b'unknown bookmark mode: %s' % bookmarksmode
         )
 
 
 @parthandler(b'phase-heads')
 def handlephases(op, inpart):
     """apply phases from bundle part to repo"""
     headsbyphase = phases.binarydecode(inpart)
     phases.updatephases(op.repo.unfiltered(), op.gettransaction, headsbyphase)
 
 
 @parthandler(b'reply:pushkey', (b'return', b'in-reply-to'))
 def handlepushkeyreply(op, inpart):
     """retrieve the result of a pushkey request"""
     ret = int(inpart.params[b'return'])
     partid = int(inpart.params[b'in-reply-to'])
     op.records.add(b'pushkey', {b'return': ret}, partid)
 
 
 @parthandler(b'obsmarkers')
 def handleobsmarker(op, inpart):
     """add a stream of obsmarkers to the repo"""
     tr = op.gettransaction()
     markerdata = inpart.read()
     if op.ui.config(b'experimental', b'obsmarkers-exchange-debug'):
         op.ui.writenoi18n(
             b'obsmarker-exchange: %i bytes received\n' % len(markerdata)
         )
     # The mergemarkers call will crash if marker creation is not enabled.
     # we want to avoid this if the part is advisory.
     if not inpart.mandatory and op.repo.obsstore.readonly:
         op.repo.ui.debug(
             b'ignoring obsolescence markers, feature not enabled\n'
         )
         return
     new = op.repo.obsstore.mergemarkers(tr, markerdata)
     op.repo.invalidatevolatilesets()
     op.records.add(b'obsmarkers', {b'new': new})
     if op.reply is not None:
         rpart = op.reply.newpart(b'reply:obsmarkers')
         rpart.addparam(
             b'in-reply-to', pycompat.bytestr(inpart.id), mandatory=False
         )
         rpart.addparam(b'new', b'%i' % new, mandatory=False)
 
 
 @parthandler(b'reply:obsmarkers', (b'new', b'in-reply-to'))
 def handleobsmarkerreply(op, inpart):
     """retrieve the result of a pushkey request"""
     ret = int(inpart.params[b'new'])
     partid = int(inpart.params[b'in-reply-to'])
     op.records.add(b'obsmarkers', {b'new': ret}, partid)
 
 
 @parthandler(b'hgtagsfnodes')
 def handlehgtagsfnodes(op, inpart):
     """Applies .hgtags fnodes cache entries to the local repo.
 
     Payload is pairs of 20 byte changeset nodes and filenodes.
     """
     # Grab the transaction so we ensure that we have the lock at this point.
     if op.ui.configbool(b'experimental', b'bundle2lazylocking'):
         op.gettransaction()
     cache = tags.hgtagsfnodescache(op.repo.unfiltered())
 
     count = 0
     while True:
         node = inpart.read(20)
         fnode = inpart.read(20)
         if len(node) < 20 or len(fnode) < 20:
             op.ui.debug(b'ignoring incomplete received .hgtags fnodes data\n')
             break
         cache.setfnode(node, fnode)
         count += 1
 
     cache.write()
     op.ui.debug(b'applied %i hgtags fnodes cache entries\n' % count)
 
 
 rbcstruct = struct.Struct(b'>III')
 
 
 @parthandler(b'cache:rev-branch-cache')
 def handlerbc(op, inpart):
     """Legacy part, ignored for compatibility with bundles from or
     for Mercurial before 5.7. Newer Mercurial computes the cache
     efficiently enough during unbundling that the additional transfer
     is unnecessary."""
 
 
 @parthandler(b'pushvars')
 def bundle2getvars(op, part):
     '''unbundle a bundle2 containing shellvars on the server'''
     # An option to disable unbundling on server-side for security reasons
     if op.ui.configbool(b'push', b'pushvars.server'):
         hookargs = {}
         for key, value in part.advisoryparams:
             key = key.upper()
             # We want pushed variables to have USERVAR_ prepended so we know
             # they came from the --pushvar flag.
             key = b"USERVAR_" + key
             hookargs[key] = value
         op.addhookargs(hookargs)
 
 
 @parthandler(b'stream2', (b'requirements', b'filecount', b'bytecount'))
 def handlestreamv2bundle(op, part):
     requirements = urlreq.unquote(part.params[b'requirements'])
     requirements = requirements.split(b',') if requirements else []
     filecount = int(part.params[b'filecount'])
     bytecount = int(part.params[b'bytecount'])
 
     repo = op.repo
     if len(repo):
         msg = _(b'cannot apply stream clone to non empty repository')
         raise error.Abort(msg)
 
     repo.ui.debug(b'applying stream bundle\n')
     streamclone.applybundlev2(repo, part, filecount, bytecount, requirements)
 
 
 @parthandler(b'stream3-exp', (b'requirements',))
 def handlestreamv3bundle(op, part):
     requirements = urlreq.unquote(part.params[b'requirements'])
     requirements = requirements.split(b',') if requirements else []
 
     repo = op.repo
     if len(repo):
         msg = _(b'cannot apply stream clone to non empty repository')
         raise error.Abort(msg)
 
     repo.ui.debug(b'applying stream bundle\n')
     streamclone.applybundlev3(repo, part, requirements)
 
 
 def widen_bundle(
     bundler, repo, oldmatcher, newmatcher, common, known, cgversion, ellipses
 ):
     """generates bundle2 for widening a narrow clone
 
     bundler is the bundle to which data should be added
     repo is the localrepository instance
     oldmatcher matches what the client already has
     newmatcher matches what the client needs (including what it already has)
     common is set of common heads between server and client
     known is a set of revs known on the client side (used in ellipses)
     cgversion is the changegroup version to send
     ellipses is boolean value telling whether to send ellipses data or not
 
     returns bundle2 of the data required for extending
     """
     commonnodes = set()
     cl = repo.changelog
     for r in repo.revs(b"::%ln", common):
         commonnodes.add(cl.node(r))
     if commonnodes:
         packer = changegroup.getbundler(
             cgversion,
             repo,
             oldmatcher=oldmatcher,
             matcher=newmatcher,
             fullnodes=commonnodes,
         )
         cgdata = packer.generate(
             {repo.nullid},
             list(commonnodes),
             False,
             b'narrow_widen',
             changelog=False,
         )
 
         part = bundler.newpart(b'changegroup', data=cgdata)
         part.addparam(b'version', cgversion)
         if scmutil.istreemanifest(repo):
             part.addparam(b'treemanifest', b'1')
     if repository.REPO_FEATURE_SIDE_DATA in repo.features:
         part.addparam(b'exp-sidedata', b'1')
         wanted = format_remote_wanted_sidedata(repo)
         part.addparam(b'exp-wanted-sidedata', wanted)
 
     return bundler

mercurial/exchange.py

@@ -1,2954 +1,2959
 # exchange.py - utility to exchange data between repos.
 #
 # Copyright 2005-2007 Olivia Mackall <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
 from __future__ import annotations
 
 import collections
 import weakref
 
 from .i18n import _
 from .node import (
     hex,
     nullrev,
 )
 from . import (
     bookmarks as bookmod,
     bundle2,
     bundlecaches,
     changegroup,
     discovery,
     error,
     lock as lockmod,
     logexchange,
     narrowspec,
     obsolete,
     obsutil,
     phases,
     pushkey,
     pycompat,
     requirements,
     scmutil,
     streamclone,
     url as urlmod,
     util,
     wireprototypes,
 )
 from .utils import (
     hashutil,
     stringutil,
     urlutil,
 )
 from .interfaces import repository
 
 urlerr = util.urlerr
 urlreq = util.urlreq
 
 _NARROWACL_SECTION = b'narrowacl'
 
 
 def readbundle(ui, fh, fname, vfs=None):
     header = changegroup.readexactly(fh, 4)
 
     alg = None
     if not fname:
         fname = b"stream"
         if not header.startswith(b'HG') and header.startswith(b'\0'):
             fh = changegroup.headerlessfixup(fh, header)
             header = b"HG10"
             alg = b'UN'
     elif vfs:
         fname = vfs.join(fname)
 
     magic, version = header[0:2], header[2:4]
 
     if magic != b'HG':
         raise error.Abort(_(b'%s: not a Mercurial bundle') % fname)
     if version == b'10':
         if alg is None:
             alg = changegroup.readexactly(fh, 2)
         return changegroup.cg1unpacker(fh, alg)
     elif version.startswith(b'2'):
         return bundle2.getunbundler(ui, fh, magicstring=magic + version)
     elif version == b'S1':
         return streamclone.streamcloneapplier(fh)
     else:
         raise error.Abort(
             _(b'%s: unknown bundle version %s') % (fname, version)
         )
 
 
 def _format_params(params):
     parts = []
     for key, value in sorted(params.items()):
         value = urlreq.quote(value)
         parts.append(b"%s=%s" % (key, value))
     return b';'.join(parts)
 
 
 def getbundlespec(ui, fh):
     """Infer the bundlespec from a bundle file handle.
 
     The input file handle is seeked and the original seek position is not
     restored.
     """
 
     def speccompression(alg):
         try:
             return util.compengines.forbundletype(alg).bundletype()[0]
         except KeyError:
             return None
 
     params = {}
 
     b = readbundle(ui, fh, None)
     if isinstance(b, changegroup.cg1unpacker):
         alg = b._type
         if alg == b'_truncatedBZ':
             alg = b'BZ'
         comp = speccompression(alg)
         if not comp:
             raise error.Abort(_(b'unknown compression algorithm: %s') % alg)
         return b'%s-v1' % comp
     elif isinstance(b, bundle2.unbundle20):
         if b'Compression' in b.params:
             comp = speccompression(b.params[b'Compression'])
             if not comp:
                 raise error.Abort(
                     _(b'unknown compression algorithm: %s') % comp
                 )
         else:
             comp = b'none'
 
         version = None
         for part in b.iterparts():
             if part.type == b'changegroup':
                 cgversion = part.params[b'version']
                 if cgversion in (b'01', b'02'):
                     version = b'v2'
                 elif cgversion in (b'03',):
                     version = b'v2'
                     params[b'cg.version'] = cgversion
                 else:
                     raise error.Abort(
                         _(
                             b'changegroup version %s does not have '
                             b'a known bundlespec'
                         )
                         % version,
                         hint=_(b'try upgrading your Mercurial client'),
                     )
             elif part.type == b'stream2' and version is None:
                 # A stream2 part requires to be part of a v2 bundle
                 requirements = urlreq.unquote(part.params[b'requirements'])
                 splitted = requirements.split()
                 params = bundle2._formatrequirementsparams(splitted)
                 return b'none-v2;stream=v2;%s' % params
             elif part.type == b'stream3-exp' and version is None:
                 # A stream3 part requires to be part of a v2 bundle
                 requirements = urlreq.unquote(part.params[b'requirements'])
                 splitted = requirements.split()
                 params = bundle2._formatrequirementsparams(splitted)
                 return b'none-v2;stream=v3-exp;%s' % params
             elif part.type == b'obsmarkers':
                 params[b'obsolescence'] = b'yes'
                 if not part.mandatory:
                     params[b'obsolescence-mandatory'] = b'no'
 
         if not version:
             params[b'changegroup'] = b'no'
             version = b'v2'
         spec = b'%s-%s' % (comp, version)
         if params:
             spec += b';'
             spec += _format_params(params)
         return spec
 
     elif isinstance(b, streamclone.streamcloneapplier):
         requirements = streamclone.readbundle1header(fh)[2]
         formatted = bundle2._formatrequirementsparams(requirements)
         return b'none-packed1;%s' % formatted
     else:
         raise error.Abort(_(b'unknown bundle type: %s') % b)
 
 
 def _computeoutgoing(repo, heads, common):
     """Computes which revs are outgoing given a set of common
     and a set of heads.
 
     This is a separate function so extensions can have access to
     the logic.
 
     Returns a discovery.outgoing object.
     """
     cl = repo.changelog
     if common:
         hasnode = cl.hasnode
         common = [n for n in common if hasnode(n)]
     else:
         common = [repo.nullid]
     if not heads:
         heads = cl.heads()
     return discovery.outgoing(repo, common, heads)
 
 
 def _checkpublish(pushop):
     repo = pushop.repo
     ui = repo.ui
     behavior = ui.config(b'experimental', b'auto-publish')
     if pushop.publish or behavior not in (b'warn', b'confirm', b'abort'):
         return
     remotephases = listkeys(pushop.remote, b'phases')
     if not remotephases.get(b'publishing', False):
         return
 
     if pushop.revs is None:
         published = repo.filtered(b'served').revs(b'not public()')
     else:
         published = repo.revs(b'::%ln - public()', pushop.revs)
         # we want to use pushop.revs in the revset even if they themselves are
         # secret, but we don't want to have anything that the server won't see
         # in the result of this expression
         published &= repo.filtered(b'served')
     if published:
         if behavior == b'warn':
             ui.warn(
                 _(b'%i changesets about to be published\n') % len(published)
             )
         elif behavior == b'confirm':
             if ui.promptchoice(
                 _(b'push and publish %i changesets (yn)?$$ &Yes $$ &No')
                 % len(published)
             ):
                 raise error.CanceledError(_(b'user quit'))
         elif behavior == b'abort':
             msg = _(b'push would publish %i changesets') % len(published)
             hint = _(
                 b"use --publish or adjust 'experimental.auto-publish'"
                 b" config"
             )
             raise error.Abort(msg, hint=hint)
 
 
 def _forcebundle1(op):
     """return true if a pull/push must use bundle1
 
     This function is used to allow testing of the older bundle version"""
     ui = op.repo.ui
     # The goal is this config is to allow developer to choose the bundle
     # version used during exchanged. This is especially handy during test.
     # Value is a list of bundle version to be picked from, highest version
     # should be used.
     #
     # developer config: devel.legacy.exchange
     exchange = ui.configlist(b'devel', b'legacy.exchange')
     forcebundle1 = b'bundle2' not in exchange and b'bundle1' in exchange
     return forcebundle1 or not op.remote.capable(b'bundle2')
 
 
 class pushoperation:
     """A object that represent a single push operation
 
     Its purpose is to carry push related state and very common operations.
 
     A new pushoperation should be created at the beginning of each push and
     discarded afterward.
     """
 
     def __init__(
         self,
         repo,
         remote,
         force=False,
         revs=None,
         newbranch=False,
         bookmarks=(),
         publish=False,
         pushvars=None,
     ):
         # 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
         # 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 topological heads before the push
         self.remoteheads = None
         # Details of the remote branch pre and post push
         #
         # mapping: {'branch': ([remoteheads],
         #                      [newheads],
         #                      [unsyncedheads],
         #                      [discardedheads])}
         # - branch: the branch name
         # - remoteheads: the list of remote heads known locally
         #                None if the branch is new
         # - newheads: the new remote heads (known locally) with outgoing pushed
         # - unsyncedheads: the list of remote heads unknown locally.
         # - discardedheads: the list of remote heads made obsolete by the push
         self.pushbranchmap = None
         # testable as a boolean indicating if any nodes are missing locally.
         self.incoming = None
         # summary of the remote phase situation
         self.remotephases = 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, list of (bm, oldnode | '', newnode | '')
         self.outbookmarks = []
         # transaction manager
         self.trmanager = None
         # map { pushkey partid -> callback handling failure}
         # used to handle exception from mandatory pushkey part failure
         self.pkfailcb = {}
         # an iterable of pushvars or None
         self.pushvars = pushvars
         # publish pushed changesets
         self.publish = publish
 
     @util.propertycache
     def futureheads(self):
         """future remote heads if the changeset push succeeds"""
         return self.outgoing.ancestorsof
 
     @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(::push_heads and ::commonheads)
         #
         # To push, we already computed
         #     common = (::commonheads)
         #     missing = ((commonheads::push_heads) - commonheads)
         #
         # So we basically search
         #
         #     almost_heads = heads((parents(missing) + push_heads) & common)
         #
         # We use "almost" here as this can return revision that are ancestors
         # of other in the set and we need to explicitly turn it into an
         # antichain later. We can do so using:
         #
         #     cheads = heads(almost_heads::almost_heads)
         #
         # In pratice the code is a bit more convulted to avoid some extra
         # computation. It aims at doing the same computation as highlighted
         # above however.
         common = self.outgoing.common
         unfi = self.repo.unfiltered()
         cl = unfi.changelog
         to_rev = cl.index.rev
         to_node = cl.node
         parent_revs = cl.parentrevs
         unselected = []
         cheads = set()
         # XXX-perf: `self.revs` and `outgoing.missing` could hold revs directly
         for n in self.revs:
             r = to_rev(n)
             if r in common:
                 cheads.add(r)
             else:
                 unselected.append(r)
         known_non_heads = cl.ancestors(cheads, inclusive=True)
         if unselected:
             missing_revs = {to_rev(n) for n in self.outgoing.missing}
             missing_revs.add(nullrev)
             root_points = set()
             for r in missing_revs:
                 p1, p2 = parent_revs(r)
                 if p1 not in missing_revs and p1 not in known_non_heads:
                     root_points.add(p1)
                 if p2 not in missing_revs and p2 not in known_non_heads:
                     root_points.add(p2)
             if root_points:
                 heads = unfi.revs('heads(%ld::%ld)', root_points, root_points)
                 cheads.update(heads)
         # XXX-perf: could this be a set of revision?
         return [to_node(r) for r in sorted(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 = {
     b'update': (
         _(b"updating bookmark %s\n"),
         _(b'updating bookmark %s failed\n'),
     ),
     b'export': (
         _(b"exporting bookmark %s\n"),
         _(b'exporting bookmark %s failed\n'),
     ),
     b'delete': (
         _(b"deleting remote bookmark %s\n"),
         _(b'deleting remote bookmark %s failed\n'),
     ),
 }
 
 
 def push(
     repo,
     remote,
     force=False,
     revs=None,
     newbranch=False,
     bookmarks=(),
     publish=False,
     opargs=None,
 ):
     """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()
     """
     if opargs is None:
         opargs = {}
     pushop = pushoperation(
         repo,
         remote,
         force,
         revs,
         newbranch,
         bookmarks,
         publish,
         **pycompat.strkwargs(opargs),
     )
     if pushop.remote.local():
         missing = (
             set(pushop.repo.requirements) - pushop.remote.local().supported
         )
         if missing:
             msg = _(
                 b"required features are not"
                 b" supported in the destination:"
                 b" %s"
             ) % (b', '.join(sorted(missing)))
             raise error.Abort(msg)
 
     if not pushop.remote.canpush():
         raise error.Abort(_(b"destination does not support push"))
 
     if not pushop.remote.capable(b'unbundle'):
         raise error.Abort(
             _(
                 b'cannot push: destination does not support the '
                 b'unbundle wire protocol command'
             )
         )
     for category in sorted(bundle2.read_remote_wanted_sidedata(pushop.remote)):
         # Check that a computer is registered for that category for at least
         # one revlog kind.
         for kind, computers in repo._sidedata_computers.items():
             if computers.get(category):
                 break
         else:
             raise error.Abort(
                 _(
                     b'cannot push: required sidedata category not supported'
                     b" by this client: '%s'"
                 )
                 % pycompat.bytestr(category)
             )
     # get lock as we might write phase data
     wlock = lock = None
     try:
         try:
             # bundle2 push may receive a reply bundle touching bookmarks
             # requiring the wlock. Take it now to ensure proper ordering.
             maypushback = pushop.ui.configbool(
                 b'experimental',
                 b'bundle2.pushback',
             )
             if (
                 (not _forcebundle1(pushop))
                 and maypushback
                 and not bookmod.bookmarksinstore(repo)
             ):
                 wlock = pushop.repo.wlock()
             lock = pushop.repo.lock()
             pushop.trmanager = transactionmanager(
                 pushop.repo, b'push-response', pushop.remote.url()
             )
         except error.LockUnavailable as err:
             # source repo cannot be locked.
             # We do not abort the push, but just disable the local phase
             # synchronisation.
             msg = b'cannot lock source repository: %s\n'
             msg %= stringutil.forcebytestr(err)
             pushop.ui.debug(msg)
 
         pushop.repo.checkpush(pushop)
         _checkpublish(pushop)
         _pushdiscovery(pushop)
         if not pushop.force:
             _checksubrepostate(pushop)
         if not _forcebundle1(pushop):
             _pushbundle2(pushop)
         _pushchangeset(pushop)
         _pushsyncphase(pushop)
         _pushobsolete(pushop)
         _pushbookmark(pushop)
         if pushop.trmanager is not None:
             pushop.trmanager.close()
     finally:
         lockmod.release(pushop.trmanager, lock, wlock)
 
     if repo.ui.configbool(b'experimental', b'remotenames'):
         logexchange.pullremotenames(repo, remote)
 
     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)
 
 
 def _checksubrepostate(pushop):
     """Ensure all outgoing referenced subrepo revisions are present locally"""
 
     repo = pushop.repo
 
     # If the repository does not use subrepos, skip the expensive
     # manifest checks.
     if not len(repo.file(b'.hgsub')) or not len(repo.file(b'.hgsubstate')):
         return
 
     for n in pushop.outgoing.missing:
         ctx = repo[n]
 
         if b'.hgsub' in ctx.manifest() and b'.hgsubstate' in ctx.files():
             for subpath in sorted(ctx.substate):
                 sub = ctx.sub(subpath)
                 sub.verify(onpush=True)
 
 
 @pushdiscovery(b'changeset')
 def _pushdiscoverychangeset(pushop):
     """discover the changeset that need to be pushed"""
     fci = discovery.findcommonincoming
     if pushop.revs:
         commoninc = fci(
             pushop.repo,
             pushop.remote,
             force=pushop.force,
             ancestorsof=pushop.revs,
         )
     else:
         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(b'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
     repo = pushop.repo
     unfi = repo.unfiltered()
     cl = unfi.changelog
     to_rev = cl.index.rev
     remotephases = listkeys(pushop.remote, b'phases')
 
     if (
         pushop.ui.configbool(b'ui', b'_usedassubrepo')
         and remotephases  # server supports phases
         and not pushop.outgoing.missing  # no changesets to be pushed
         and remotephases.get(b'publishing', False)
     ):
         # 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 3781 case!
         # We drop the possible phase synchronisation done by
         # courtesy to publish changesets possibly locally draft
         # on the remote.
         pushop.outdatedphases = []
         pushop.fallbackoutdatedphases = []
         return
 
     fallbackheads_rev = {to_rev(n) for n in pushop.fallbackheads}
     pushop.remotephases = phases.RemotePhasesSummary(
         pushop.repo,
         fallbackheads_rev,
         remotephases,
     )
     droots = set(pushop.remotephases.draft_roots)
 
     fallback_publishing = pushop.remotephases.publishing
     push_publishing = pushop.remotephases.publishing or pushop.publish
     missing_revs = {to_rev(n) for n in outgoing.missing}
     drafts = unfi._phasecache.get_raw_set(unfi, phases.draft)
 
     if fallback_publishing:
         fallback_roots = droots - missing_revs
         revset = b'heads(%ld::%ld)'
     else:
         fallback_roots = droots - drafts
         fallback_roots -= missing_revs
         # Get the list of all revs draft on remote but public here.
         revset = b'heads((%ld::%ld) and public())'
     if not fallback_roots:
         fallback = fallback_rev = []
     else:
         fallback_rev = unfi.revs(revset, fallback_roots, fallbackheads_rev)
         fallback = [repo[r] for r in fallback_rev]
 
     if push_publishing:
         published = missing_revs.copy()
     else:
         published = missing_revs - drafts
     if pushop.publish:
         published.update(fallbackheads_rev & drafts)
     elif fallback:
         published.update(fallback_rev)
 
     pushop.outdatedphases = [repo[r] for r in cl.headrevs(published)]
     pushop.fallbackoutdatedphases = fallback
 
 
 @pushdiscovery(b'obsmarker')
 def _pushdiscoveryobsmarkers(pushop):
     if not obsolete.isenabled(pushop.repo, obsolete.exchangeopt):
         return
 
     if not pushop.repo.obsstore:
         return
 
     if b'obsolete' not in listkeys(pushop.remote, b'namespaces'):
         return
 
     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(b'::%ln', pushop.futureheads))
-    pushop.outobsmarkers = pushop.repo.obsstore.relevantmarkers(nodes)
+    revs = repo.revs(b'::%ln', pushop.futureheads)
+    pushop.outobsmarkers = pushop.repo.obsstore.relevantmarkers(revs=revs)
 
 
 @pushdiscovery(b'bookmarks')
 def _pushdiscoverybookmarks(pushop):
     ui = pushop.ui
     repo = pushop.repo.unfiltered()
     remote = pushop.remote
     ui.debug(b"checking for updated bookmarks\n")
     ancestors = ()
     if pushop.revs:
         revnums = pycompat.maplist(repo.changelog.rev, pushop.revs)
         ancestors = repo.changelog.ancestors(revnums, inclusive=True)
 
     remotebookmark = bookmod.unhexlifybookmarks(listkeys(remote, b'bookmarks'))
 
     explicit = {
         repo._bookmarks.expandname(bookmark) for bookmark in pushop.bookmarks
     }
 
     comp = bookmod.comparebookmarks(repo, repo._bookmarks, remotebookmark)
     return _processcompared(pushop, ancestors, explicit, remotebookmark, comp)
 
 
 def _processcompared(pushop, pushed, explicit, remotebms, comp):
     """take decision on bookmarks to push to the remote repo
 
     Exists to help extensions alter this behavior.
     """
     addsrc, adddst, advsrc, advdst, diverge, differ, invalid, same = comp
 
     repo = pushop.repo
 
     for b, scid, dcid in advsrc:
         if b in explicit:
             explicit.remove(b)
         if not pushed or repo[scid].rev() in pushed:
             pushop.outbookmarks.append((b, dcid, scid))
     # search added bookmark
     for b, scid, dcid in addsrc:
         if b in explicit:
             explicit.remove(b)
             if bookmod.isdivergent(b):
                 pushop.ui.warn(_(b'cannot push divergent bookmark %s!\n') % b)
                 pushop.bkresult = 2
             elif pushed and repo[scid].rev() not in pushed:
                 # in case of race or secret
                 msg = _(b'cannot push bookmark X without its revision: %s!\n')
                 pushop.ui.warn(msg % b)
                 pushop.bkresult = 2
             else:
                 pushop.outbookmarks.append((b, b'', scid))
     # search for overwritten bookmark
     for b, scid, dcid in list(advdst) + list(diverge) + list(differ):
         if b in explicit:
             explicit.remove(b)
             if not pushed or repo[scid].rev() in pushed:
                 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, b''))
     # 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
         pushop.ui.warn(
             _(
                 b'bookmark %s does not exist on the local '
                 b'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 = _(b"push includes obsolete changeset: %s!")
             mspd = _(b"push includes phase-divergent changeset: %s!")
             mscd = _(b"push includes content-divergent changeset: %s!")
             mst = {
                 b"orphan": _(b"push includes orphan changeset: %s!"),
                 b"phase-divergent": mspd,
                 b"content-divergent": mscd,
             }
             # 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.ancestorsof:
                 ctx = unfi[node]
                 if ctx.obsolete():
                     raise error.Abort(mso % ctx)
                 elif ctx.isunstable():
                     # TODO print more than one instability in the abort
                     # message
                     raise error.Abort(mst[ctx.instabilities()[0]] % ctx)
 
         discovery.checkheads(pushop)
     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 independent function to aid extensions
     """
     # * 'force' do not check for push race,
     # * if we don't push anything, there are nothing to check.
     if not pushop.force and pushop.outgoing.ancestorsof:
         allowunrelated = b'related' in bundler.capabilities.get(
             b'checkheads', ()
         )
         emptyremote = pushop.pushbranchmap is None
         if not allowunrelated or emptyremote:
             bundler.newpart(b'check:heads', data=iter(pushop.remoteheads))
         else:
             affected = set()
             for branch, heads in pushop.pushbranchmap.items():
                 remoteheads, newheads, unsyncedheads, discardedheads = heads
                 if remoteheads is not None:
                     remote = set(remoteheads)
                     affected |= set(discardedheads) & remote
                     affected |= remote - set(newheads)
             if affected:
                 data = iter(sorted(affected))
                 bundler.newpart(b'check:updated-heads', data=data)
 
 
 def _pushing(pushop):
     """return True if we are pushing anything"""
     return bool(
         pushop.outgoing.missing
         or pushop.outdatedphases
         or pushop.outobsmarkers
         or pushop.outbookmarks
     )
 
 
 @b2partsgenerator(b'check-bookmarks')
 def _pushb2checkbookmarks(pushop, bundler):
     """insert bookmark move checking"""
     if not _pushing(pushop) or pushop.force:
         return
     b2caps = bundle2.bundle2caps(pushop.remote)
     hasbookmarkcheck = b'bookmarks' in b2caps
     if not (pushop.outbookmarks and hasbookmarkcheck):
         return
     data = []
     for book, old, new in pushop.outbookmarks:
         data.append((book, old))
     checkdata = bookmod.binaryencode(pushop.repo, data)
     bundler.newpart(b'check:bookmarks', data=checkdata)
 
 
 @b2partsgenerator(b'check-phases')
 def _pushb2checkphases(pushop, bundler):
     """insert phase move checking"""
     if not _pushing(pushop) or pushop.force:
         return
     b2caps = bundle2.bundle2caps(pushop.remote)
     hasphaseheads = b'heads' in b2caps.get(b'phases', ())
     if pushop.remotephases is not None and hasphaseheads:
         # check that the remote phase has not changed
         checks = {p: [] for p in phases.allphases}
         to_node = pushop.repo.unfiltered().changelog.node
         checks[phases.public].extend(
             to_node(r) for r in pushop.remotephases.public_heads
         )
         checks[phases.draft].extend(
             to_node(r) for r in pushop.remotephases.draft_roots
         )
         if any(checks.values()):
             for phase in checks:
                 checks[phase].sort()
             checkdata = phases.binaryencode(checks)
             bundler.newpart(b'check:phases', data=checkdata)
 
 
 @b2partsgenerator(b'changeset')
 def _pushb2ctx(pushop, bundler):
     """handle changegroup push through bundle2
 
     addchangegroup result is stored in the ``pushop.cgresult`` attribute.
     """
     if b'changesets' in pushop.stepsdone:
         return
     pushop.stepsdone.add(b'changesets')
     # Send known heads to the server for race detection.
     if not _pushcheckoutgoing(pushop):
         return
     pushop.repo.prepushoutgoinghooks(pushop)
 
     _pushb2ctxcheckheads(pushop, bundler)
 
     b2caps = bundle2.bundle2caps(pushop.remote)
     version = b'01'
     cgversions = b2caps.get(b'changegroup')
     if cgversions:  # 3.1 and 3.2 ship with an empty value
         cgversions = [
             v
             for v in cgversions
             if v in changegroup.supportedoutgoingversions(pushop.repo)
         ]
         if not cgversions:
             raise error.Abort(_(b'no common changegroup version'))
         version = max(cgversions)
 
     remote_sidedata = bundle2.read_remote_wanted_sidedata(pushop.remote)
     cgstream = changegroup.makestream(
         pushop.repo,
         pushop.outgoing,
         version,
         b'push',
         bundlecaps=b2caps,
         remote_sidedata=remote_sidedata,
     )
     cgpart = bundler.newpart(b'changegroup', data=cgstream)
     if cgversions:
         cgpart.addparam(b'version', version)
     if scmutil.istreemanifest(pushop.repo):
         cgpart.addparam(b'treemanifest', b'1')
     if repository.REPO_FEATURE_SIDE_DATA in pushop.repo.features:
         cgpart.addparam(b'exp-sidedata', b'1')
 
     def handlereply(op):
         """extract addchangegroup returns from server reply"""
         cgreplies = op.records.getreplies(cgpart.id)
         assert len(cgreplies[b'changegroup']) == 1
         pushop.cgresult = cgreplies[b'changegroup'][0][b'return']
 
     return handlereply
 
 
 @b2partsgenerator(b'phase')
 def _pushb2phases(pushop, bundler):
     """handle phase push through bundle2"""
     if b'phases' in pushop.stepsdone:
         return
     b2caps = bundle2.bundle2caps(pushop.remote)
     ui = pushop.repo.ui
 
     legacyphase = b'phases' in ui.configlist(b'devel', b'legacy.exchange')
     haspushkey = b'pushkey' in b2caps
     hasphaseheads = b'heads' in b2caps.get(b'phases', ())
 
     if hasphaseheads and not legacyphase:
         return _pushb2phaseheads(pushop, bundler)
     elif haspushkey:
         return _pushb2phasespushkey(pushop, bundler)
 
 
 def _pushb2phaseheads(pushop, bundler):
     """push phase information through a bundle2 - binary part"""
     pushop.stepsdone.add(b'phases')
     if pushop.outdatedphases:
         updates = {p: [] for p in phases.allphases}
         updates[0].extend(h.node() for h in pushop.outdatedphases)
         phasedata = phases.binaryencode(updates)
         bundler.newpart(b'phase-heads', data=phasedata)
 
 
 def _pushb2phasespushkey(pushop, bundler):
     """push phase information through a bundle2 - pushkey part"""
     pushop.stepsdone.add(b'phases')
     part2node = []
 
     def handlefailure(pushop, exc):
         targetid = int(exc.partid)
         for partid, node in part2node:
             if partid == targetid:
                 raise error.Abort(_(b'updating %s to public failed') % node)
 
     enc = pushkey.encode
     for newremotehead in pushop.outdatedphases:
         part = bundler.newpart(b'pushkey')
         part.addparam(b'namespace', enc(b'phases'))
         part.addparam(b'key', enc(newremotehead.hex()))
         part.addparam(b'old', enc(b'%d' % phases.draft))
         part.addparam(b'new', enc(b'%d' % 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[b'pushkey']
             assert len(results) <= 1
             msg = None
             if not results:
                 msg = _(b'server ignored update of %s to public!\n') % node
             elif not int(results[0][b'return']):
                 msg = _(b'updating %s to public failed!\n') % node
             if msg is not None:
                 pushop.ui.warn(msg)
 
     return handlereply
 
 
 @b2partsgenerator(b'obsmarkers')
 def _pushb2obsmarkers(pushop, bundler):
     if b'obsmarkers' in pushop.stepsdone:
         return
     remoteversions = bundle2.obsmarkersversion(bundler.capabilities)
     if obsolete.commonversion(remoteversions) is None:
         return
     pushop.stepsdone.add(b'obsmarkers')
     if pushop.outobsmarkers:
         markers = obsutil.sortedmarkers(pushop.outobsmarkers)
         bundle2.buildobsmarkerspart(bundler, markers)
 
 
 @b2partsgenerator(b'bookmarks')
 def _pushb2bookmarks(pushop, bundler):
     """handle bookmark push through bundle2"""
     if b'bookmarks' in pushop.stepsdone:
         return
     b2caps = bundle2.bundle2caps(pushop.remote)
 
     legacy = pushop.repo.ui.configlist(b'devel', b'legacy.exchange')
     legacybooks = b'bookmarks' in legacy
 
     if not legacybooks and b'bookmarks' in b2caps:
         return _pushb2bookmarkspart(pushop, bundler)
     elif b'pushkey' in b2caps:
         return _pushb2bookmarkspushkey(pushop, bundler)
 
 
 def _bmaction(old, new):
     """small utility for bookmark pushing"""
     if not old:
         return b'export'
     elif not new:
         return b'delete'
     return b'update'
 
 
 def _abortonsecretctx(pushop, node, b):
     """abort if a given bookmark points to a secret changeset"""
     if node and pushop.repo[node].phase() == phases.secret:
         raise error.Abort(
             _(b'cannot push bookmark %s as it points to a secret changeset') % b
         )
 
 
 def _pushb2bookmarkspart(pushop, bundler):
     pushop.stepsdone.add(b'bookmarks')
     if not pushop.outbookmarks:
         return
 
     allactions = []
     data = []
     for book, old, new in pushop.outbookmarks:
         _abortonsecretctx(pushop, new, book)
         data.append((book, new))
         allactions.append((book, _bmaction(old, new)))
     checkdata = bookmod.binaryencode(pushop.repo, data)
     bundler.newpart(b'bookmarks', data=checkdata)
 
     def handlereply(op):
         ui = pushop.ui
         # if success
         for book, action in allactions:
             ui.status(bookmsgmap[action][0] % book)
 
     return handlereply
 
 
 def _pushb2bookmarkspushkey(pushop, bundler):
     pushop.stepsdone.add(b'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:
         _abortonsecretctx(pushop, new, book)
         part = bundler.newpart(b'pushkey')
         part.addparam(b'namespace', enc(b'bookmarks'))
         part.addparam(b'key', enc(book))
         part.addparam(b'old', enc(hex(old)))
         part.addparam(b'new', enc(hex(new)))
         action = b'update'
         if not old:
             action = b'export'
         elif not new:
             action = b'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[b'pushkey']
             assert len(results) <= 1
             if not results:
                 pushop.ui.warn(_(b'server ignored bookmark %s update\n') % book)
             else:
                 ret = int(results[0][b'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
 
 
 @b2partsgenerator(b'pushvars', idx=0)
 def _getbundlesendvars(pushop, bundler):
     '''send shellvars via bundle2'''
     pushvars = pushop.pushvars
     if pushvars:
         shellvars = {}
         for raw in pushvars:
             if b'=' not in raw:
                 msg = (
                     b"unable to parse variable '%s', should follow "
                     b"'KEY=VALUE' or 'KEY=' format"
                 )
                 raise error.Abort(msg % raw)
             k, v = raw.split(b'=', 1)
             shellvars[k] = v
 
         part = bundler.newpart(b'pushvars')
 
         for key, value in shellvars.items():
             part.addparam(key, value, mandatory=False)
 
 
 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(
         b'experimental', b'bundle2.pushback'
     )
 
     # create reply capability
     capsblob = bundle2.encodecaps(
         bundle2.getrepocaps(pushop.repo, allowpushback=pushback, role=b'client')
     )
     bundler.newpart(b'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:
             with pushop.remote.commandexecutor() as e:
                 reply = e.callcommand(
                     b'unbundle',
                     {
                         b'bundle': stream,
                         b'heads': [b'force'],
                         b'url': pushop.remote.url(),
                     },
                 ).result()
         except error.BundleValueError as exc:
             raise error.RemoteError(_(b'missing support for %s') % exc)
         try:
             trgetter = None
             if pushback:
                 trgetter = pushop.trmanager.transaction
             op = bundle2.processbundle(
                 pushop.repo,
                 reply,
                 trgetter,
                 remote=pushop.remote,
             )
         except error.BundleValueError as exc:
             raise error.RemoteError(_(b'missing support for %s') % exc)
         except bundle2.AbortFromPart as exc:
             pushop.ui.error(_(b'remote: %s\n') % exc)
             if exc.hint is not None:
                 pushop.ui.error(_(b'remote: %s\n') % (b'(%s)' % exc.hint))
             raise error.RemoteError(_(b'push failed on remote'))
     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 b'changesets' in pushop.stepsdone:
         return
     pushop.stepsdone.add(b'changesets')
     if not _pushcheckoutgoing(pushop):
         return
 
     # Should have verified this in push().
     assert pushop.remote.capable(b'unbundle')
 
     pushop.repo.prepushoutgoinghooks(pushop)
     outgoing = pushop.outgoing
     # 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
         fastpath = True
     else:
         fastpath = False
 
     cg = changegroup.makechangegroup(
         pushop.repo,
         outgoing,
         b'01',
         b'push',
         fastpath=fastpath,
         bundlecaps=bundlecaps,
     )
 
     # apply changegroup to remote
     # 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 = [b'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())
 
 
 def _pushsyncphase(pushop):
     """synchronise phase information locally and remotely"""
     cheads = pushop.commonheads
     # even when we don't push, exchanging phase data is useful
     remotephases = listkeys(pushop.remote, b'phases')
     if (
         pushop.ui.configbool(b'ui', b'_usedassubrepo')
         and remotephases  # server supports phases
         and pushop.cgresult is None  # nothing was pushed
         and remotephases.get(b'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 = {b'publishing': b'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:
         unfi = pushop.repo.unfiltered()
         to_rev = unfi.changelog.index.rev
         to_node = unfi.changelog.node
         cheads_revs = [to_rev(n) for n in cheads]
         pheads_revs, _dr = phases.analyze_remote_phases(
             pushop.repo,
             cheads_revs,
             remotephases,
         )
         pheads = [to_node(r) for r in pheads_revs]
         ### Apply remote phase on local
         if remotephases.get(b'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 b'phases' in pushop.stepsdone:
                 # phases already pushed though bundle2
                 return
             outdated = pushop.outdatedphases
         else:
             outdated = pushop.fallbackoutdatedphases
 
         pushop.stepsdone.add(b'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:
             with pushop.remote.commandexecutor() as e:
                 r = e.callcommand(
                     b'pushkey',
                     {
                         b'namespace': b'phases',
                         b'key': newremotehead.hex(),
                         b'old': b'%d' % phases.draft,
                         b'new': b'%d' % phases.public,
                     },
                 ).result()
 
             if not r:
                 pushop.ui.warn(
                     _(b'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(
                 _(
                     b'cannot lock source repo, skipping '
                     b'local %s phase update\n'
                 )
                 % phasestr
             )
 
 
 def _pushobsolete(pushop):
     """utility function to push obsolete markers to a remote"""
     if b'obsmarkers' in pushop.stepsdone:
         return
     repo = pushop.repo
     remote = pushop.remote
     pushop.stepsdone.add(b'obsmarkers')
     if pushop.outobsmarkers:
         pushop.ui.debug(b'try to push obsolete markers to remote\n')
         rslts = []
         markers = obsutil.sortedmarkers(pushop.outobsmarkers)
         remotedata = obsolete._pushkeyescape(markers)
         for key in sorted(remotedata, reverse=True):
             # reverse sort to ensure we end with dump0
             data = remotedata[key]
             rslts.append(remote.pushkey(b'obsolete', key, b'', data))
         if [r for r in rslts if not r]:
             msg = _(b'failed to push some obsolete markers!\n')
             repo.ui.warn(msg)
 
 
 def _pushbookmark(pushop):
     """Update bookmark position on remote"""
     if pushop.cgresult == 0 or b'bookmarks' in pushop.stepsdone:
         return
     pushop.stepsdone.add(b'bookmarks')
     ui = pushop.ui
     remote = pushop.remote
 
     for b, old, new in pushop.outbookmarks:
         action = b'update'
         if not old:
             action = b'export'
         elif not new:
             action = b'delete'
 
         with remote.commandexecutor() as e:
             r = e.callcommand(
                 b'pushkey',
                 {
                     b'namespace': b'bookmarks',
                     b'key': b,
                     b'old': hex(old),
                     b'new': hex(new),
                 },
             ).result()
 
         if r:
             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:
     """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,
         includepats=None,
         excludepats=None,
         depth=None,
         path=None,
     ):
         # repo we pull into
         self.repo = repo
         # repo we pull from
         self.remote = remote
         # path object used to build this remote
         #
         # Ideally, the remote peer would carry that directly.
         self.remote_path = path
         # revision we try to pull (None is "all")
         self.heads = heads
         # bookmark pulled explicitly
         self.explicitbookmarks = [
             repo._bookmarks.expandname(bookmark) for bookmark in 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()
         # Whether we attempted a clone from pre-generated bundles.
         self.clonebundleattempted = False
         # Set of file patterns to include.
         self.includepats = includepats
         # Set of file patterns to exclude.
         self.excludepats = excludepats
         # Number of ancestor changesets to pull from each pulled head.
         self.depth = depth
 
     @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 not _forcebundle1(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(util.transactional):
     """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 = b'%s\n%s' % (self.source, urlutil.hidepassword(self.url))
             self._tr = self.repo.transaction(trname)
             self._tr.hookargs[b'source'] = self.source
             self._tr.hookargs[b'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 listkeys(remote, namespace):
     with remote.commandexecutor() as e:
         return e.callcommand(b'listkeys', {b'namespace': namespace}).result()
 
 
 def _fullpullbundle2(repo, pullop):
     # The server may send a partial reply, i.e. when inlining
     # pre-computed bundles. In that case, update the common
     # set based on the results and pull another bundle.
     #
     # There are two indicators that the process is finished:
     # - no changeset has been added, or
     # - all remote heads are known locally.
     # The head check must use the unfiltered view as obsoletion
     # markers can hide heads.
     unfi = repo.unfiltered()
     unficl = unfi.changelog
 
     def headsofdiff(h1, h2):
         """Returns heads(h1 % h2)"""
         res = unfi.set(b'heads(%ln %% %ln)', h1, h2)
         return {ctx.node() for ctx in res}
 
     def headsofunion(h1, h2):
         """Returns heads((h1 + h2) - null)"""
         res = unfi.set(b'heads((%ln + %ln - null))', h1, h2)
         return {ctx.node() for ctx in res}
 
     while True:
         old_heads = unficl.heads()
         clstart = len(unficl)
         _pullbundle2(pullop)
         if requirements.NARROW_REQUIREMENT in repo.requirements:
             # XXX narrow clones filter the heads on the server side during
             # XXX getbundle and result in partial replies as well.
             # XXX Disable pull bundles in this case as band aid to avoid
             # XXX extra round trips.
             break
         if clstart == len(unficl):
             break
         if all(unficl.hasnode(n) for n in pullop.rheads):
             break
         new_heads = headsofdiff(unficl.heads(), old_heads)
         pullop.common = headsofunion(new_heads, pullop.common)
         pullop.rheads = set(pullop.rheads) - pullop.common
 
 
 def add_confirm_callback(repo, pullop):
     """adds a finalize callback to transaction which can be used to show stats
     to user and confirm the pull before committing transaction"""
 
     tr = pullop.trmanager.transaction()
     scmutil.registersummarycallback(
         repo, tr, txnname=b'pull', as_validator=True
     )
     reporef = weakref.ref(repo.unfiltered())
 
     def prompt(tr):
         repo = reporef()
         cm = _(b'accept incoming changes (yn)?$$ &Yes $$ &No')
         if repo.ui.promptchoice(cm):
             raise error.Abort(b"user aborted")
 
     tr.addvalidator(b'900-pull-prompt', prompt)
 
 
 def pull(
     repo,
     remote,
     path=None,
     heads=None,
     force=False,
     bookmarks=(),
     opargs=None,
     streamclonerequested=None,
     includepats=None,
     excludepats=None,
     depth=None,
     confirm=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.
     ``includepats`` and ``excludepats`` define explicit file patterns to
     include and exclude in storage, respectively. If not defined, narrow
     patterns from the repo instance are used, if available.
     ``depth`` is an integer indicating the DAG depth of history we're
     interested in. If defined, for each revision specified in ``heads``, we
     will fetch up to this many of its ancestors and data associated with them.
     ``confirm`` is a boolean indicating whether the pull should be confirmed
     before committing the transaction. This overrides HGPLAIN.
 
     Returns the ``pulloperation`` created for this pull.
     """
     if opargs is None:
         opargs = {}
 
     # We allow the narrow patterns to be passed in explicitly to provide more
     # flexibility for API consumers.
     if includepats is not None or excludepats is not None:
         includepats = includepats or set()
         excludepats = excludepats or set()
     else:
         includepats, excludepats = repo.narrowpats
 
     narrowspec.validatepatterns(includepats)
     narrowspec.validatepatterns(excludepats)
 
     pullop = pulloperation(
         repo,
         remote,
         path=path,
         heads=heads,
         force=force,
         bookmarks=bookmarks,
         streamclonerequested=streamclonerequested,
         includepats=includepats,
         excludepats=excludepats,
         depth=depth,
         **pycompat.strkwargs(opargs),
     )
 
     peerlocal = pullop.remote.local()
     if peerlocal:
         missing = set(peerlocal.requirements) - pullop.repo.supported
         if missing:
             msg = _(
                 b"required features are not"
                 b" supported in the destination:"
                 b" %s"
             ) % (b', '.join(sorted(missing)))
             raise error.Abort(msg)
 
     for category in repo._wanted_sidedata:
         # Check that a computer is registered for that category for at least
         # one revlog kind.
         for kind, computers in repo._sidedata_computers.items():
             if computers.get(category):
                 break
         else:
             # This should never happen since repos are supposed to be able to
             # generate the sidedata they require.
             raise error.ProgrammingError(
                 _(
                     b'sidedata category requested by local side without local'
                     b"support: '%s'"
                 )
                 % pycompat.bytestr(category)
             )
 
     pullop.trmanager = transactionmanager(repo, b'pull', remote.url())
     wlock = util.nullcontextmanager
     if not bookmod.bookmarksinstore(repo):
         wlock = repo.wlock
     with wlock(), repo.lock(), pullop.trmanager:
         if confirm or (
             repo.ui.configbool(b"pull", b"confirm") and not repo.ui.plain()
         ):
             add_confirm_callback(repo, pullop)
 
         # This should ideally be in _pullbundle2(). However, it needs to run
         # before discovery to avoid extra work.
         _maybeapplyclonebundle(pullop)
         streamclone.maybeperformlegacystreamclone(pullop)
         _pulldiscovery(pullop)
         if pullop.canusebundle2:
             _fullpullbundle2(repo, pullop)
         _pullchangeset(pullop)
         _pullphase(pullop)
         _pullbookmarks(pullop)
         _pullobsolete(pullop)
 
     # storing remotenames
     if repo.ui.configbool(b'experimental', b'remotenames'):
         logexchange.pullremotenames(repo, remote)
 
     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(b'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 b'listkeys' in pullop.remotebundle2caps:
         # all known bundle2 servers now support listkeys, but lets be nice with
         # new implementation.
         return
     books = listkeys(pullop.remote, b'bookmarks')
     pullop.remotebookmarks = bookmod.unhexlifybookmarks(books)
 
 
 @pulldiscovery(b'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
     has_node = pullop.repo.unfiltered().changelog.index.has_node
     if fetch and rheads:
         # If a remote heads is filtered locally, 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)
         for n in rheads:
             if has_node(n):
                 if n not in scommon:
                     common.append(n)
         if set(rheads).issubset(set(common)):
             fetch = []
     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 = {b'bundlecaps': caps20to10(pullop.repo, role=b'client')}
 
     # make ui easier to access
     ui = pullop.repo.ui
 
     # At the moment we don't do stream clones over bundle2. If that is
     # implemented then here's where the check for that will go.
     streaming = streamclone.canperformstreamclone(pullop, bundle2=True)[0]
 
     # declare pull perimeters
     kwargs[b'common'] = pullop.common
     kwargs[b'heads'] = pullop.heads or pullop.rheads
 
     # check server supports narrow and then adding includepats and excludepats
     servernarrow = pullop.remote.capable(wireprototypes.NARROWCAP)
     if servernarrow and pullop.includepats:
         kwargs[b'includepats'] = pullop.includepats
     if servernarrow and pullop.excludepats:
         kwargs[b'excludepats'] = pullop.excludepats
 
     if streaming:
         kwargs[b'cg'] = False
         kwargs[b'stream'] = True
         pullop.stepsdone.add(b'changegroup')
         pullop.stepsdone.add(b'phases')
 
     else:
         # pulling changegroup
         pullop.stepsdone.add(b'changegroup')
 
         kwargs[b'cg'] = pullop.fetch
 
         legacyphase = b'phases' in ui.configlist(b'devel', b'legacy.exchange')
         hasbinaryphase = b'heads' in pullop.remotebundle2caps.get(b'phases', ())
         if not legacyphase and hasbinaryphase:
             kwargs[b'phases'] = True
             pullop.stepsdone.add(b'phases')
 
         if b'listkeys' in pullop.remotebundle2caps:
             if b'phases' not in pullop.stepsdone:
                 kwargs[b'listkeys'] = [b'phases']
 
     bookmarksrequested = False
     legacybookmark = b'bookmarks' in ui.configlist(b'devel', b'legacy.exchange')
     hasbinarybook = b'bookmarks' in pullop.remotebundle2caps
 
     if pullop.remotebookmarks is not None:
         pullop.stepsdone.add(b'request-bookmarks')
 
     if (
         b'request-bookmarks' not in pullop.stepsdone
         and pullop.remotebookmarks is None
         and not legacybookmark
         and hasbinarybook
     ):
         kwargs[b'bookmarks'] = True
         bookmarksrequested = True
 
     if b'listkeys' in pullop.remotebundle2caps:
         if b'request-bookmarks' not in pullop.stepsdone:
             # make sure to always includes bookmark data when migrating
             # `hg incoming --bundle` to using this function.
             pullop.stepsdone.add(b'request-bookmarks')
             kwargs.setdefault(b'listkeys', []).append(b'bookmarks')
 
     # If this is a full pull / clone and the server supports the clone bundles
     # feature, tell the server whether we attempted a clone bundle. The
     # presence of this flag indicates the client supports clone bundles. This
     # will enable the server to treat clients that support clone bundles
     # differently from those that don't.
     if (
         pullop.remote.capable(b'clonebundles')
         and pullop.heads is None
         and list(pullop.common) == [pullop.repo.nullid]
     ):
         kwargs[b'cbattempted'] = pullop.clonebundleattempted
 
     if streaming:
         pullop.repo.ui.status(_(b'streaming all changes\n'))
     elif not pullop.fetch:
         pullop.repo.ui.status(_(b"no changes found\n"))
         pullop.cgresult = 0
     else:
         if pullop.heads is None and list(pullop.common) == [pullop.repo.nullid]:
             pullop.repo.ui.status(_(b"requesting all changes\n"))
     if obsolete.isenabled(pullop.repo, obsolete.exchangeopt):
         remoteversions = bundle2.obsmarkersversion(pullop.remotebundle2caps)
         if obsolete.commonversion(remoteversions) is not None:
             kwargs[b'obsmarkers'] = True
             pullop.stepsdone.add(b'obsmarkers')
     _pullbundle2extraprepare(pullop, kwargs)
 
     remote_sidedata = bundle2.read_remote_wanted_sidedata(pullop.remote)
     if remote_sidedata:
         kwargs[b'remote_sidedata'] = remote_sidedata
 
     with pullop.remote.commandexecutor() as e:
         args = dict(kwargs)
         args[b'source'] = b'pull'
         bundle = e.callcommand(b'getbundle', args).result()
 
         try:
             op = bundle2.bundleoperation(
                 pullop.repo,
                 pullop.gettransaction,
                 source=b'pull',
                 remote=pullop.remote,
             )
             op.modes[b'bookmarks'] = b'records'
             bundle2.processbundle(
                 pullop.repo,
                 bundle,
                 op=op,
                 remote=pullop.remote,
             )
         except bundle2.AbortFromPart as exc:
             pullop.repo.ui.error(_(b'remote: abort: %s\n') % exc)
             raise error.RemoteError(_(b'pull failed on remote'), hint=exc.hint)
         except error.BundleValueError as exc:
             raise error.RemoteError(_(b'missing support for %s') % exc)
 
     if pullop.fetch:
         pullop.cgresult = bundle2.combinechangegroupresults(op)
 
     # processing phases change
     for namespace, value in op.records[b'listkeys']:
         if namespace == b'phases':
             _pullapplyphases(pullop, value)
 
     # processing bookmark update
     if bookmarksrequested:
         books = {}
         for record in op.records[b'bookmarks']:
             books[record[b'bookmark']] = record[b"node"]
         pullop.remotebookmarks = books
     else:
         for namespace, value in op.records[b'listkeys']:
             if namespace == b'bookmarks':
                 pullop.remotebookmarks = bookmod.unhexlifybookmarks(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"""
 
 
 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 b'changegroup' in pullop.stepsdone:
         return
     pullop.stepsdone.add(b'changegroup')
     if not pullop.fetch:
         pullop.repo.ui.status(_(b"no changes found\n"))
         pullop.cgresult = 0
         return
     tr = pullop.gettransaction()
     if pullop.heads is None and list(pullop.common) == [pullop.repo.nullid]:
         pullop.repo.ui.status(_(b"requesting all changes\n"))
     elif pullop.heads is None and pullop.remote.capable(b'changegroupsubset'):
         # issue1320, avoid a race if remote changed after discovery
         pullop.heads = pullop.rheads
 
     if pullop.remote.capable(b'getbundle'):
         # TODO: get bundlecaps from remote
         cg = pullop.remote.getbundle(
             b'pull', common=pullop.common, heads=pullop.heads or pullop.rheads
         )
     elif pullop.heads is None:
         with pullop.remote.commandexecutor() as e:
             cg = e.callcommand(
                 b'changegroup',
                 {
                     b'nodes': pullop.fetch,
                     b'source': b'pull',
                 },
             ).result()
 
     elif not pullop.remote.capable(b'changegroupsubset'):
         raise error.Abort(
             _(
                 b"partial pull cannot be done because "
                 b"other repository doesn't support "
                 b"changegroupsubset."
             )
         )
     else:
         with pullop.remote.commandexecutor() as e:
             cg = e.callcommand(
                 b'changegroupsubset',
                 {
                     b'bases': pullop.fetch,
                     b'heads': pullop.heads,
                     b'source': b'pull',
                 },
             ).result()
 
     bundleop = bundle2.applybundle(
         pullop.repo,
         cg,
         tr,
         b'pull',
         pullop.remote.url(),
         remote=pullop.remote,
     )
     pullop.cgresult = bundle2.combinechangegroupresults(bundleop)
 
 
 def _pullphase(pullop):
     # Get remote phases data from remote
     if b'phases' in pullop.stepsdone:
         return
     remotephases = listkeys(pullop.remote, b'phases')
     _pullapplyphases(pullop, remotephases)
 
 
 def _pullapplyphases(pullop, remotephases):
     """apply phase movement from observed remote state"""
     if b'phases' in pullop.stepsdone:
         return
     pullop.stepsdone.add(b'phases')
     publishing = bool(remotephases.get(b'publishing', False))
     if remotephases and not publishing:
         unfi = pullop.repo.unfiltered()
         to_rev = unfi.changelog.index.rev
         to_node = unfi.changelog.node
         pulledsubset_revs = [to_rev(n) for n in pullop.pulledsubset]
         # remote is new and non-publishing
         pheads_revs, _dr = phases.analyze_remote_phases(
             pullop.repo,
             pulledsubset_revs,
             remotephases,
         )
         pheads = [to_node(r) for r in pheads_revs]
         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.index.get_rev
     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 b'bookmarks' in pullop.stepsdone:
         return
     pullop.stepsdone.add(b'bookmarks')
     repo = pullop.repo
     remotebookmarks = pullop.remotebookmarks
     bookmarks_mode = None
     if pullop.remote_path is not None:
         bookmarks_mode = pullop.remote_path.bookmarks_mode
     bookmod.updatefromremote(
         repo.ui,
         repo,
         remotebookmarks,
         pullop.remote.url(),
         pullop.gettransaction,
         explicit=pullop.explicitbookmarks,
         mode=bookmarks_mode,
     )
 
 
 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 b'obsmarkers' in pullop.stepsdone:
         return
     pullop.stepsdone.add(b'obsmarkers')
     tr = None
     if obsolete.isenabled(pullop.repo, obsolete.exchangeopt):
         pullop.repo.ui.debug(b'fetching remote obsolete markers\n')
         remoteobs = listkeys(pullop.remote, b'obsolete')
         if b'dump0' in remoteobs:
             tr = pullop.gettransaction()
             markers = []
             for key in sorted(remoteobs, reverse=True):
                 if key.startswith(b'dump'):
                     data = util.b85decode(remoteobs[key])
                     version, newmarks = obsolete._readmarkers(data)
                     markers += newmarks
             if markers:
                 pullop.repo.obsstore.add(tr, markers)
             pullop.repo.invalidatevolatilesets()
     return tr
 
 
 def applynarrowacl(repo, kwargs):
     """Apply narrow fetch access control.
 
     This massages the named arguments for getbundle wire protocol commands
     so requested data is filtered through access control rules.
     """
     ui = repo.ui
     # TODO this assumes existence of HTTP and is a layering violation.
     username = ui.shortuser(ui.environ.get(b'REMOTE_USER') or ui.username())
     user_includes = ui.configlist(
         _NARROWACL_SECTION,
         username + b'.includes',
         ui.configlist(_NARROWACL_SECTION, b'default.includes'),
     )
     user_excludes = ui.configlist(
         _NARROWACL_SECTION,
         username + b'.excludes',
         ui.configlist(_NARROWACL_SECTION, b'default.excludes'),
     )
     if not user_includes:
         raise error.Abort(
             _(b"%s configuration for user %s is empty")
             % (_NARROWACL_SECTION, username)
         )
 
     user_includes = [
         b'path:.' if p == b'*' else b'path:' + p for p in user_includes
     ]
     user_excludes = [
         b'path:.' if p == b'*' else b'path:' + p for p in user_excludes
     ]
 
     req_includes = set(kwargs.get('includepats', []))
     req_excludes = set(kwargs.get('excludepats', []))
 
     req_includes, req_excludes, invalid_includes = narrowspec.restrictpatterns(
         req_includes, req_excludes, user_includes, user_excludes
     )
 
     if invalid_includes:
         raise error.Abort(
             _(b"The following includes are not accessible for %s: %s")
             % (username, stringutil.pprint(invalid_includes))
         )
 
     new_args = {}
     new_args.update(kwargs)
     new_args['narrow'] = True
     new_args['narrow_acl'] = True
     new_args['includepats'] = req_includes
     if req_excludes:
         new_args['excludepats'] = req_excludes
 
     return new_args
 
 
 def _computeellipsis(repo, common, heads, known, match, depth=None):
     """Compute the shape of a narrowed DAG.
 
     Args:
       repo: The repository we're transferring.
       common: The roots of the DAG range we're transferring.
               May be just [nullid], which means all ancestors of heads.
       heads: The heads of the DAG range we're transferring.
       match: The narrowmatcher that allows us to identify relevant changes.
       depth: If not None, only consider nodes to be full nodes if they are at
              most depth changesets away from one of heads.
 
     Returns:
       A tuple of (visitnodes, relevant_nodes, ellipsisroots) where:
 
         visitnodes: The list of nodes (either full or ellipsis) which
                     need to be sent to the client.
         relevant_nodes: The set of changelog nodes which change a file inside
                  the narrowspec. The client needs these as non-ellipsis nodes.
         ellipsisroots: A dict of {rev: parents} that is used in
                        narrowchangegroup to produce ellipsis nodes with the
                        correct parents.
     """
     cl = repo.changelog
     mfl = repo.manifestlog
 
     clrev = cl.rev
 
     commonrevs = {clrev(n) for n in common} | {nullrev}
     headsrevs = {clrev(n) for n in heads}
 
     if depth:
         revdepth = {h: 0 for h in headsrevs}
 
     ellipsisheads = collections.defaultdict(set)
     ellipsisroots = collections.defaultdict(set)
 
     def addroot(head, curchange):
         """Add a root to an ellipsis head, splitting heads with 3 roots."""
         ellipsisroots[head].add(curchange)
         # Recursively split ellipsis heads with 3 roots by finding the
         # roots' youngest common descendant which is an elided merge commit.
         # That descendant takes 2 of the 3 roots as its own, and becomes a
         # root of the head.
         while len(ellipsisroots[head]) > 2:
             child, roots = splithead(head)
             splitroots(head, child, roots)
             head = child  # Recurse in case we just added a 3rd root
 
     def splitroots(head, child, roots):
         ellipsisroots[head].difference_update(roots)
         ellipsisroots[head].add(child)
         ellipsisroots[child].update(roots)
         ellipsisroots[child].discard(child)
 
     def splithead(head):
         r1, r2, r3 = sorted(ellipsisroots[head])
         for nr1, nr2 in ((r2, r3), (r1, r3), (r1, r2)):
             mid = repo.revs(
                 b'sort(merge() & %d::%d & %d::%d, -rev)', nr1, head, nr2, head
             )
             for j in mid:
                 if j == nr2:
                     return nr2, (nr1, nr2)
                 if j not in ellipsisroots or len(ellipsisroots[j]) < 2:
                     return j, (nr1, nr2)
         raise error.Abort(
             _(
                 b'Failed to split up ellipsis node! head: %d, '
                 b'roots: %d %d %d'
             )
             % (head, r1, r2, r3)
         )
 
     missing = list(cl.findmissingrevs(common=commonrevs, heads=headsrevs))
     visit = reversed(missing)
     relevant_nodes = set()
     visitnodes = [cl.node(m) for m in missing]
     required = set(headsrevs) | known
     for rev in visit:
         clrev = cl.changelogrevision(rev)
         ps = [prev for prev in cl.parentrevs(rev) if prev != nullrev]
         if depth is not None:
             curdepth = revdepth[rev]
             for p in ps:
                 revdepth[p] = min(curdepth + 1, revdepth.get(p, depth + 1))
         needed = False
         shallow_enough = depth is None or revdepth[rev] <= depth
         if shallow_enough:
             curmf = mfl[clrev.manifest].read()
             if ps:
                 # We choose to not trust the changed files list in
                 # changesets because it's not always correct. TODO: could
                 # we trust it for the non-merge case?
                 p1mf = mfl[cl.changelogrevision(ps[0]).manifest].read()
                 needed = bool(curmf.diff(p1mf, match))
                 if not needed and len(ps) > 1:
                     # For merge changes, the list of changed files is not
                     # helpful, since we need to emit the merge if a file
                     # in the narrow spec has changed on either side of the
                     # merge. As a result, we do a manifest diff to check.
                     p2mf = mfl[cl.changelogrevision(ps[1]).manifest].read()
                     needed = bool(curmf.diff(p2mf, match))
             else:
                 # For a root node, we need to include the node if any
                 # files in the node match the narrowspec.
                 needed = any(curmf.walk(match))
 
         if needed:
             for head in ellipsisheads[rev]:
                 addroot(head, rev)
             for p in ps:
                 required.add(p)
             relevant_nodes.add(cl.node(rev))
         else:
             if not ps:
                 ps = [nullrev]
             if rev in required:
                 for head in ellipsisheads[rev]:
                     addroot(head, rev)
                 for p in ps:
                     ellipsisheads[p].add(rev)
             else:
                 for p in ps:
                     ellipsisheads[p] |= ellipsisheads[rev]
 
     # add common changesets as roots of their reachable ellipsis heads
     for c in commonrevs:
         for head in ellipsisheads[c]:
             addroot(head, c)
     return visitnodes, relevant_nodes, ellipsisroots
 
 
 def caps20to10(repo, role):
     """return a set with appropriate options to use bundle20 during getbundle"""
     caps = {b'HG20'}
     capsblob = bundle2.encodecaps(bundle2.getrepocaps(repo, role=role))
     caps.add(b'bundle2=' + urlreq.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 bundle2requested(bundlecaps):
     if bundlecaps is not None:
         return any(cap.startswith(b'HG2') for cap in bundlecaps)
     return False
 
 
 def getbundlechunks(
     repo,
     source,
     heads=None,
     common=None,
     bundlecaps=None,
     remote_sidedata=None,
     **kwargs,
 ):
     """Return chunks constituting a bundle's raw data.
 
     Could be a bundle HG10 or a bundle HG20 depending on bundlecaps
     passed.
 
     Returns a 2-tuple of a dict with metadata about the generated bundle
     and an iterator over raw chunks (of varying sizes).
     """
     kwargs = pycompat.byteskwargs(kwargs)
     info = {}
     usebundle2 = bundle2requested(bundlecaps)
     # bundle10 case
     if not usebundle2:
         if bundlecaps and not kwargs.get(b'cg', True):
             raise ValueError(
                 _(b'request for bundle10 must include changegroup')
             )
 
         if kwargs:
             raise ValueError(
                 _(b'unsupported getbundle arguments: %s')
                 % b', '.join(sorted(kwargs.keys()))
             )
         outgoing = _computeoutgoing(repo, heads, common)
         info[b'bundleversion'] = 1
         return (
             info,
             changegroup.makestream(
                 repo,
                 outgoing,
                 b'01',
                 source,
                 bundlecaps=bundlecaps,
                 remote_sidedata=remote_sidedata,
             ),
         )
 
     # bundle20 case
     info[b'bundleversion'] = 2
     b2caps = {}
     for bcaps in bundlecaps:
         if bcaps.startswith(b'bundle2='):
             blob = urlreq.unquote(bcaps[len(b'bundle2=') :])
             b2caps.update(bundle2.decodecaps(blob))
     bundler = bundle2.bundle20(repo.ui, b2caps)
 
     kwargs[b'heads'] = heads
     kwargs[b'common'] = common
 
     for name in getbundle2partsorder:
         func = getbundle2partsmapping[name]
         func(
             bundler,
             repo,
             source,
             bundlecaps=bundlecaps,
             b2caps=b2caps,
             remote_sidedata=remote_sidedata,
             **pycompat.strkwargs(kwargs),
         )
 
     info[b'prefercompressed'] = bundler.prefercompressed
 
     return info, bundler.getchunks()
 
 
 @getbundle2partsgenerator(b'stream')
 def _getbundlestream2(bundler, repo, *args, **kwargs):
     return bundle2.addpartbundlestream2(bundler, repo, **kwargs)
 
 
 @getbundle2partsgenerator(b'changegroup')
 def _getbundlechangegrouppart(
     bundler,
     repo,
     source,
     bundlecaps=None,
     b2caps=None,
     heads=None,
     common=None,
     remote_sidedata=None,
     **kwargs,
 ):
     """add a changegroup part to the requested bundle"""
     if not kwargs.get('cg', True) or not b2caps:
         return
 
     version = b'01'
     cgversions = b2caps.get(b'changegroup')
     if cgversions:  # 3.1 and 3.2 ship with an empty value
         cgversions = [
             v
             for v in cgversions
             if v in changegroup.supportedoutgoingversions(repo)
         ]
         if not cgversions:
             raise error.Abort(_(b'no common changegroup version'))
         version = max(cgversions)
 
     outgoing = _computeoutgoing(repo, heads, common)
     if not outgoing.missing:
         return
 
     if kwargs.get('narrow', False):
         include = sorted(filter(bool, kwargs.get('includepats', [])))
         exclude = sorted(filter(bool, kwargs.get('excludepats', [])))
         matcher = narrowspec.match(repo.root, include=include, exclude=exclude)
     else:
         matcher = None
 
     cgstream = changegroup.makestream(
         repo,
         outgoing,
         version,
         source,
         bundlecaps=bundlecaps,
         matcher=matcher,
         remote_sidedata=remote_sidedata,
     )
 
     part = bundler.newpart(b'changegroup', data=cgstream)
     if cgversions:
         part.addparam(b'version', version)
 
     part.addparam(b'nbchanges', b'%d' % len(outgoing.missing), mandatory=False)
 
     if scmutil.istreemanifest(repo):
         part.addparam(b'treemanifest', b'1')
 
     if repository.REPO_FEATURE_SIDE_DATA in repo.features:
         part.addparam(b'exp-sidedata', b'1')
         sidedata = bundle2.format_remote_wanted_sidedata(repo)
         part.addparam(b'exp-wanted-sidedata', sidedata)
 
     if (
         kwargs.get('narrow', False)
         and kwargs.get('narrow_acl', False)
         and (include or exclude)
     ):
         # this is mandatory because otherwise ACL clients won't work
         narrowspecpart = bundler.newpart(b'Narrow:responsespec')
         narrowspecpart.data = b'%s\0%s' % (
             b'\n'.join(include),
             b'\n'.join(exclude),
         )
 
 
 @getbundle2partsgenerator(b'bookmarks')
 def _getbundlebookmarkpart(
     bundler, repo, source, bundlecaps=None, b2caps=None, **kwargs
 ):
     """add a bookmark part to the requested bundle"""
     if not kwargs.get('bookmarks', False):
         return
     if not b2caps or b'bookmarks' not in b2caps:
         raise error.Abort(_(b'no common bookmarks exchange method'))
     books = bookmod.listbinbookmarks(repo)
     data = bookmod.binaryencode(repo, books)
     if data:
         bundler.newpart(b'bookmarks', data=data)
 
 
 @getbundle2partsgenerator(b'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(b'listkeys')
         part.addparam(b'namespace', namespace)
         keys = repo.listkeys(namespace).items()
         part.data = pushkey.encodekeys(keys)
 
 
 @getbundle2partsgenerator(b'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):
+        unfi_cl = repo.unfiltered().changelog
         if heads is None:
-            heads = repo.heads()
-        subset = [c.node() for c in repo.set(b'::%ln', heads)]
-        markers = repo.obsstore.relevantmarkers(subset)
+            headrevs = repo.changelog.headrevs()
+        else:
+            get_rev = unfi_cl.index.get_rev
+            headrevs = [get_rev(node) for node in heads]
+            headrevs = [rev for rev in headrevs if rev is not None]
+        revs = unfi_cl.ancestors(headrevs, inclusive=True)
+        markers = repo.obsstore.relevantmarkers(revs=revs)
         markers = obsutil.sortedmarkers(markers)
         bundle2.buildobsmarkerspart(bundler, markers)
 
 
 @getbundle2partsgenerator(b'phases')
 def _getbundlephasespart(
     bundler, repo, source, bundlecaps=None, b2caps=None, heads=None, **kwargs
 ):
     """add phase heads part to the requested bundle"""
     if kwargs.get('phases', False):
         if not b2caps or b'heads' not in b2caps.get(b'phases'):
             raise error.Abort(_(b'no common phases exchange method'))
         if heads is None:
             heads = repo.heads()
 
         headsbyphase = collections.defaultdict(set)
         if repo.publishing():
             headsbyphase[phases.public] = heads
         else:
             # find the appropriate heads to move
 
             phase = repo._phasecache.phase
             node = repo.changelog.node
             rev = repo.changelog.rev
             for h in heads:
                 headsbyphase[phase(repo, rev(h))].add(h)
             seenphases = list(headsbyphase.keys())
 
             # We do not handle anything but public and draft phase for now)
             if seenphases:
                 assert max(seenphases) <= phases.draft
 
             # if client is pulling non-public changesets, we need to find
             # intermediate public heads.
             draftheads = headsbyphase.get(phases.draft, set())
             if draftheads:
                 publicheads = headsbyphase.get(phases.public, set())
 
                 revset = b'heads(only(%ln, %ln) and public())'
                 extraheads = repo.revs(revset, draftheads, publicheads)
                 for r in extraheads:
                     headsbyphase[phases.public].add(node(r))
 
         # transform data in a format used by the encoding function
         phasemapping = {
             phase: sorted(headsbyphase[phase]) for phase in phases.allphases
         }
 
         # generate the actual part
         phasedata = phases.binaryencode(phasemapping)
         bundler.newpart(b'phase-heads', data=phasedata)
 
 
 @getbundle2partsgenerator(b'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 b2caps or not (kwargs.get('cg', True) and b'hgtagsfnodes' in b2caps):
         return
 
     outgoing = _computeoutgoing(repo, heads, common)
     bundle2.addparttagsfnodescache(repo, bundler, outgoing)
 
 
 @getbundle2partsgenerator(b'cache:rev-branch-cache')
 def _getbundlerevbranchcache(
     bundler,
     repo,
     source,
     bundlecaps=None,
     b2caps=None,
     heads=None,
     common=None,
     **kwargs,
 ):
     """Transfer the rev-branch-cache mapping
 
     The payload is a series of data related to each branch
 
     1) branch name length
     2) number of open heads
     3) number of closed heads
     4) open heads nodes
     5) closed heads nodes
     """
     # Don't send unless:
     # - changeset are being exchanged,
     # - the client supports it.
     # - narrow bundle isn't in play (not currently compatible).
     if (
         not kwargs.get('cg', True)
         or not b2caps
         or b'rev-branch-cache' not in b2caps
         or kwargs.get('narrow', False)
         or repo.ui.has_section(_NARROWACL_SECTION)
     ):
         return
 
     outgoing = _computeoutgoing(repo, heads, common)
     bundle2.addpartrevbranchcache(repo, bundler, outgoing)
 
 
 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 = hashutil.sha1(b''.join(sorted(heads))).digest()
     if not (
         their_heads == [b'force']
         or their_heads == heads
         or their_heads == [b'hashed', heads_hash]
     ):
         # someone else committed/pushed/unbundled while we
         # were transferring data
         raise error.PushRaced(
             b'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(
         b'experimental', b'bundle2-output-capture'
     )
     if url.startswith(b'remote:http:') or url.startswith(b'remote:https:'):
         captureoutput = True
     try:
         # note: outside bundle1, 'heads' is expected to be empty and this
         # 'check_heads' call wil be a no-op
         check_heads(repo, heads, b'uploading changes')
         # push can proceed
         if not isinstance(cg, bundle2.unbundle20):
             # legacy case: bundle1 (changegroup 01)
             txnname = b"\n".join([source, urlutil.hidepassword(url)])
             with repo.lock(), repo.transaction(txnname) as tr:
                 op = bundle2.applybundle(repo, cg, tr, source, url)
                 r = bundle2.combinechangegroupresults(op)
         else:
             r = None
             try:
 
                 def gettransaction():
                     if not lockandtr[2]:
                         if not bookmod.bookmarksinstore(repo):
                             lockandtr[0] = repo.wlock()
                         lockandtr[1] = repo.lock()
                         lockandtr[2] = repo.transaction(source)
                         lockandtr[2].hookargs[b'source'] = source
                         lockandtr[2].hookargs[b'url'] = url
                         lockandtr[2].hookargs[b'bundle2'] = b'1'
                     return lockandtr[2]
 
                 # Do greedy locking by default until we're satisfied with lazy
                 # locking.
                 if not repo.ui.configbool(
                     b'experimental', b'bundle2lazylocking'
                 ):
                     gettransaction()
 
                 op = bundle2.bundleoperation(
                     repo,
                     gettransaction,
                     captureoutput=captureoutput,
                     source=b'push',
                 )
                 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(b'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(
                             b'output', data=output, mandatory=False
                         )
                         parts.append(part)
 
                 raise
     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(b'ui', b'clonebundles'):
         return
 
     # Only run if local repo is empty.
     if len(repo):
         return
 
     if pullop.heads:
         return
 
     if not remote.capable(b'clonebundles'):
         return
 
     with remote.commandexecutor() as e:
         res = e.callcommand(b'clonebundles', {}).result()
 
     # If we call the wire protocol command, that's good enough to record the
     # attempt.
     pullop.clonebundleattempted = True
 
     entries = bundlecaches.parseclonebundlesmanifest(repo, res)
     if not entries:
         repo.ui.note(
             _(
                 b'no clone bundles available on remote; '
                 b'falling back to regular clone\n'
             )
         )
         return
 
     entries = bundlecaches.filterclonebundleentries(
         repo, entries, streamclonerequested=pullop.streamclonerequested
     )
 
     if not entries:
         # There is a thundering herd concern here. However, if a server
         # operator doesn't advertise bundles appropriate for its clients,
         # they deserve what's coming. Furthermore, from a client's
         # perspective, no automatic fallback would mean not being able to
         # clone!
         repo.ui.warn(
             _(
                 b'no compatible clone bundles available on server; '
                 b'falling back to regular clone\n'
             )
         )
         repo.ui.warn(
             _(b'(you may want to report this to the server operator)\n')
         )
         return
 
     entries = bundlecaches.sortclonebundleentries(repo.ui, entries)
 
     url = entries[0][b'URL']
     repo.ui.status(_(b'applying clone bundle from %s\n') % url)
     if trypullbundlefromurl(repo.ui, repo, url, remote):
         repo.ui.status(_(b'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(b'ui', b'clonebundlefallback'):
         repo.ui.warn(_(b'falling back to normal clone\n'))
     else:
         raise error.Abort(
             _(b'error applying bundle'),
             hint=_(
                 b'if this error persists, consider contacting '
                 b'the server operator or disable clone '
                 b'bundles via '
                 b'"--config ui.clonebundles=false"'
             ),
         )
 
 
 def inline_clone_bundle_open(ui, url, peer):
     if not peer:
         raise error.Abort(_(b'no remote repository supplied for %s' % url))
     clonebundleid = url[len(bundlecaches.CLONEBUNDLESCHEME) :]
     peerclonebundle = peer.get_cached_bundle_inline(clonebundleid)
     return util.chunkbuffer(peerclonebundle)
 
 
 def trypullbundlefromurl(ui, repo, url, peer):
     """Attempt to apply a bundle from a URL."""
     with repo.lock(), repo.transaction(b'bundleurl') as tr:
         try:
             if url.startswith(bundlecaches.CLONEBUNDLESCHEME):
                 fh = inline_clone_bundle_open(ui, url, peer)
             else:
                 fh = urlmod.open(ui, url)
             cg = readbundle(ui, fh, b'stream')
 
             if isinstance(cg, streamclone.streamcloneapplier):
                 cg.apply(repo)
             else:
                 bundle2.applybundle(repo, cg, tr, b'clonebundles', url)
             return True
         except urlerr.httperror as e:
             ui.warn(
                 _(b'HTTP error fetching bundle: %s\n')
                 % stringutil.forcebytestr(e)
             )
         except urlerr.urlerror as e:
             ui.warn(
                 _(b'error fetching bundle: %s\n')
                 % stringutil.forcebytestr(e.reason)
             )
 
         return False

mercurial/obsolete.py

@@ -1,1156 +1,1177
 # obsolete.py - obsolete markers handling
 #
 # Copyright 2012 Pierre-Yves David <[e-mail]>
 #                Logilab SA        <[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.
 
 """Obsolete marker handling
 
 An obsolete marker maps an old changeset to a list of new
 changesets. If the list of new changesets is empty, the old changeset
 is said to be "killed". Otherwise, the old changeset is being
 "replaced" by the new changesets.
 
 Obsolete markers can be used to record and distribute changeset graph
 transformations performed by history rewrite operations, and help
 building new tools to reconcile conflicting rewrite actions. To
 facilitate conflict resolution, markers include various annotations
 besides old and news changeset identifiers, such as creation date or
 author name.
 
 The old obsoleted changeset is called a "predecessor" and possible
 replacements are called "successors". Markers that used changeset X as
 a predecessor are called "successor markers of X" because they hold
 information about the successors of X. Markers that use changeset Y as
 a successors are call "predecessor markers of Y" because they hold
 information about the predecessors of Y.
 
 Examples:
 
 - When changeset A is replaced by changeset A', one marker is stored:
 
     (A, (A',))
 
 - When changesets A and B are folded into a new changeset C, two markers are
   stored:
 
     (A, (C,)) and (B, (C,))
 
 - When changeset A is simply "pruned" from the graph, a marker is created:
 
     (A, ())
 
 - When changeset A is split into B and C, a single marker is used:
 
     (A, (B, C))
 
   We use a single marker to distinguish the "split" case from the "divergence"
   case. If two independent operations rewrite the same changeset A in to A' and
   A'', we have an error case: divergent rewriting. We can detect it because
   two markers will be created independently:
 
   (A, (B,)) and (A, (C,))
 
 Format
 ------
 
 Markers are stored in an append-only file stored in
 '.hg/store/obsstore'.
 
 The file starts with a version header:
 
 - 1 unsigned byte: version number, starting at zero.
 
 The header is followed by the markers. Marker format depend of the version. See
 comment associated with each format for details.
 
 """
 
 from __future__ import annotations
 
 import binascii
 import struct
 import weakref
 
 from .i18n import _
 from .node import (
     bin,
     hex,
 )
 from . import (
     encoding,
     error,
     obsutil,
     phases,
     policy,
     pycompat,
     util,
 )
 from .utils import (
     dateutil,
     hashutil,
 )
 
 parsers = policy.importmod('parsers')
 
 _pack = struct.pack
 _unpack = struct.unpack
 _calcsize = struct.calcsize
 propertycache = util.propertycache
 
 # Options for obsolescence
 createmarkersopt = b'createmarkers'
 allowunstableopt = b'allowunstable'
 allowdivergenceopt = b'allowdivergence'
 exchangeopt = b'exchange'
 
 
 def _getoptionvalue(repo, option):
     """Returns True if the given repository has the given obsolete option
     enabled.
     """
     configkey = b'evolution.%s' % option
     newconfig = repo.ui.configbool(b'experimental', configkey)
 
     # Return the value only if defined
     if newconfig is not None:
         return newconfig
 
     # Fallback on generic option
     try:
         return repo.ui.configbool(b'experimental', b'evolution')
     except (error.ConfigError, AttributeError):
         # Fallback on old-fashion config
         # inconsistent config: experimental.evolution
         result = set(repo.ui.configlist(b'experimental', b'evolution'))
 
         if b'all' in result:
             return True
 
         # Temporary hack for next check
         newconfig = repo.ui.config(b'experimental', b'evolution.createmarkers')
         if newconfig:
             result.add(b'createmarkers')
 
         return option in result
 
 
 def getoptions(repo):
     """Returns dicts showing state of obsolescence features."""
 
     createmarkersvalue = _getoptionvalue(repo, createmarkersopt)
     if createmarkersvalue:
         unstablevalue = _getoptionvalue(repo, allowunstableopt)
         divergencevalue = _getoptionvalue(repo, allowdivergenceopt)
         exchangevalue = _getoptionvalue(repo, exchangeopt)
     else:
         # if we cannot create obsolescence markers, we shouldn't exchange them
         # or perform operations that lead to instability or divergence
         unstablevalue = False
         divergencevalue = False
         exchangevalue = False
 
     return {
         createmarkersopt: createmarkersvalue,
         allowunstableopt: unstablevalue,
         allowdivergenceopt: divergencevalue,
         exchangeopt: exchangevalue,
     }
 
 
 def isenabled(repo, option):
     """Returns True if the given repository has the given obsolete option
     enabled.
     """
     return getoptions(repo)[option]
 
 
 # Creating aliases for marker flags because evolve extension looks for
 # bumpedfix in obsolete.py
 bumpedfix = obsutil.bumpedfix
 usingsha256 = obsutil.usingsha256
 
 ## Parsing and writing of version "0"
 #
 # The header is followed by the markers. Each marker is made of:
 #
 # - 1 uint8 : number of new changesets "N", can be zero.
 #
 # - 1 uint32: metadata size "M" in bytes.
 #
 # - 1 byte: a bit field. It is reserved for flags used in common
 #   obsolete marker operations, to avoid repeated decoding of metadata
 #   entries.
 #
 # - 20 bytes: obsoleted changeset identifier.
 #
 # - N*20 bytes: new changesets identifiers.
 #
 # - M bytes: metadata as a sequence of nul-terminated strings. Each
 #   string contains a key and a value, separated by a colon ':', without
 #   additional encoding. Keys cannot contain '\0' or ':' and values
 #   cannot contain '\0'.
 _fm0version = 0
 _fm0fixed = b'>BIB20s'
 _fm0node = b'20s'
 _fm0fsize = _calcsize(_fm0fixed)
 _fm0fnodesize = _calcsize(_fm0node)
 
 
 def _fm0readmarkers(data, off, stop):
     # Loop on markers
     while off < stop:
         # read fixed part
         cur = data[off : off + _fm0fsize]
         off += _fm0fsize
         numsuc, mdsize, flags, pre = _unpack(_fm0fixed, cur)
         # read replacement
         sucs = ()
         if numsuc:
             s = _fm0fnodesize * numsuc
             cur = data[off : off + s]
             sucs = _unpack(_fm0node * numsuc, cur)
             off += s
         # read metadata
         # (metadata will be decoded on demand)
         metadata = data[off : off + mdsize]
         if len(metadata) != mdsize:
             raise error.Abort(
                 _(
                     b'parsing obsolete marker: metadata is too '
                     b'short, %d bytes expected, got %d'
                 )
                 % (mdsize, len(metadata))
             )
         off += mdsize
         metadata = _fm0decodemeta(metadata)
         try:
             when, offset = metadata.pop(b'date', b'0 0').split(b' ')
             date = float(when), int(offset)
         except ValueError:
             date = (0.0, 0)
         parents = None
         if b'p2' in metadata:
             parents = (metadata.pop(b'p1', None), metadata.pop(b'p2', None))
         elif b'p1' in metadata:
             parents = (metadata.pop(b'p1', None),)
         elif b'p0' in metadata:
             parents = ()
         if parents is not None:
             try:
                 parents = tuple(bin(p) for p in parents)
                 # if parent content is not a nodeid, drop the data
                 for p in parents:
                     if len(p) != 20:
                         parents = None
                         break
             except binascii.Error:
                 # if content cannot be translated to nodeid drop the data.
                 parents = None
 
         metadata = tuple(sorted(metadata.items()))
 
         yield (pre, sucs, flags, metadata, date, parents)
 
 
 def _fm0encodeonemarker(marker):
     pre, sucs, flags, metadata, date, parents = marker
     if flags & usingsha256:
         raise error.Abort(_(b'cannot handle sha256 with old obsstore format'))
     metadata = dict(metadata)
     time, tz = date
     metadata[b'date'] = b'%r %i' % (time, tz)
     if parents is not None:
         if not parents:
             # mark that we explicitly recorded no parents
             metadata[b'p0'] = b''
         for i, p in enumerate(parents, 1):
             metadata[b'p%i' % i] = hex(p)
     metadata = _fm0encodemeta(metadata)
     numsuc = len(sucs)
     format = _fm0fixed + (_fm0node * numsuc)
     data = [numsuc, len(metadata), flags, pre]
     data.extend(sucs)
     return _pack(format, *data) + metadata
 
 
 def _fm0encodemeta(meta):
     """Return encoded metadata string to string mapping.
 
     Assume no ':' in key and no '\0' in both key and value."""
     for key, value in meta.items():
         if b':' in key or b'\0' in key:
             raise ValueError(b"':' and '\0' are forbidden in metadata key'")
         if b'\0' in value:
             raise ValueError(b"':' is forbidden in metadata value'")
     return b'\0'.join([b'%s:%s' % (k, meta[k]) for k in sorted(meta)])
 
 
 def _fm0decodemeta(data):
     """Return string to string dictionary from encoded version."""
     d = {}
     for l in data.split(b'\0'):
         if l:
             key, value = l.split(b':', 1)
             d[key] = value
     return d
 
 
 ## Parsing and writing of version "1"
 #
 # The header is followed by the markers. Each marker is made of:
 #
 # - uint32: total size of the marker (including this field)
 #
 # - float64: date in seconds since epoch
 #
 # - int16: timezone offset in minutes
 #
 # - uint16: a bit field. It is reserved for flags used in common
 #   obsolete marker operations, to avoid repeated decoding of metadata
 #   entries.
 #
 # - uint8: number of successors "N", can be zero.
 #
 # - uint8: number of parents "P", can be zero.
 #
 #     0: parents data stored but no parent,
 #     1: one parent stored,
 #     2: two parents stored,
 #     3: no parent data stored
 #
 # - uint8: number of metadata entries M
 #
 # - 20 or 32 bytes: predecessor changeset identifier.
 #
 # - N*(20 or 32) bytes: successors changesets identifiers.
 #
 # - P*(20 or 32) bytes: parents of the predecessors changesets.
 #
 # - M*(uint8, uint8): size of all metadata entries (key and value)
 #
 # - remaining bytes: the metadata, each (key, value) pair after the other.
 _fm1version = 1
 _fm1fixed = b'>IdhHBBB'
 _fm1nodesha1 = b'20s'
 _fm1nodesha256 = b'32s'
 _fm1nodesha1size = _calcsize(_fm1nodesha1)
 _fm1nodesha256size = _calcsize(_fm1nodesha256)
 _fm1fsize = _calcsize(_fm1fixed)
 _fm1parentnone = 3
 _fm1metapair = b'BB'
 _fm1metapairsize = _calcsize(_fm1metapair)
 
 
 def _fm1purereadmarkers(data, off, stop):
     # make some global constants local for performance
     noneflag = _fm1parentnone
     sha2flag = usingsha256
     sha1size = _fm1nodesha1size
     sha2size = _fm1nodesha256size
     sha1fmt = _fm1nodesha1
     sha2fmt = _fm1nodesha256
     metasize = _fm1metapairsize
     metafmt = _fm1metapair
     fsize = _fm1fsize
     unpack = _unpack
 
     # Loop on markers
     ufixed = struct.Struct(_fm1fixed).unpack
 
     while off < stop:
         # read fixed part
         o1 = off + fsize
         t, secs, tz, flags, numsuc, numpar, nummeta = ufixed(data[off:o1])
 
         if flags & sha2flag:
             nodefmt = sha2fmt
             nodesize = sha2size
         else:
             nodefmt = sha1fmt
             nodesize = sha1size
 
         (prec,) = unpack(nodefmt, data[o1 : o1 + nodesize])
         o1 += nodesize
 
         # read 0 or more successors
         if numsuc == 1:
             o2 = o1 + nodesize
             sucs = (data[o1:o2],)
         else:
             o2 = o1 + nodesize * numsuc
             sucs = unpack(nodefmt * numsuc, data[o1:o2])
 
         # read parents
         if numpar == noneflag:
             o3 = o2
             parents = None
         elif numpar == 1:
             o3 = o2 + nodesize
             parents = (data[o2:o3],)
         else:
             o3 = o2 + nodesize * numpar
             parents = unpack(nodefmt * numpar, data[o2:o3])
 
         # read metadata
         off = o3 + metasize * nummeta
         metapairsize = unpack(b'>' + (metafmt * nummeta), data[o3:off])
         metadata = []
         for idx in range(0, len(metapairsize), 2):
             o1 = off + metapairsize[idx]
             o2 = o1 + metapairsize[idx + 1]
             metadata.append((data[off:o1], data[o1:o2]))
             off = o2
 
         yield (prec, sucs, flags, tuple(metadata), (secs, tz * 60), parents)
 
 
 def _fm1encodeonemarker(marker):
     pre, sucs, flags, metadata, date, parents = marker
     # determine node size
     _fm1node = _fm1nodesha1
     if flags & usingsha256:
         _fm1node = _fm1nodesha256
     numsuc = len(sucs)
     numextranodes = 1 + numsuc
     if parents is None:
         numpar = _fm1parentnone
     else:
         numpar = len(parents)
         numextranodes += numpar
     formatnodes = _fm1node * numextranodes
     formatmeta = _fm1metapair * len(metadata)
     format = _fm1fixed + formatnodes + formatmeta
     # tz is stored in minutes so we divide by 60
     tz = date[1] // 60
     data = [None, date[0], tz, flags, numsuc, numpar, len(metadata), pre]
     data.extend(sucs)
     if parents is not None:
         data.extend(parents)
     totalsize = _calcsize(format)
     for key, value in metadata:
         lk = len(key)
         lv = len(value)
         if lk > 255:
             msg = (
                 b'obsstore metadata key cannot be longer than 255 bytes'
                 b' (key "%s" is %u bytes)'
             ) % (key, lk)
             raise error.ProgrammingError(msg)
         if lv > 255:
             msg = (
                 b'obsstore metadata value cannot be longer than 255 bytes'
                 b' (value "%s" for key "%s" is %u bytes)'
             ) % (value, key, lv)
             raise error.ProgrammingError(msg)
         data.append(lk)
         data.append(lv)
         totalsize += lk + lv
     data[0] = totalsize
     data = [_pack(format, *data)]
     for key, value in metadata:
         data.append(key)
         data.append(value)
     return b''.join(data)
 
 
 def _fm1readmarkers(data, off, stop):
     native = getattr(parsers, 'fm1readmarkers', None)
     if not native:
         return _fm1purereadmarkers(data, off, stop)
     return native(data, off, stop)
 
 
 # mapping to read/write various marker formats
 # <version> -> (decoder, encoder)
 formats = {
     _fm0version: (_fm0readmarkers, _fm0encodeonemarker),
     _fm1version: (_fm1readmarkers, _fm1encodeonemarker),
 }
 
 
 def _readmarkerversion(data):
     return _unpack(b'>B', data[0:1])[0]
 
 
 @util.nogc
 def _readmarkers(data, off=None, stop=None):
     """Read and enumerate markers from raw data"""
     diskversion = _readmarkerversion(data)
     if not off:
         off = 1  # skip 1 byte version number
     if stop is None:
         stop = len(data)
     if diskversion not in formats:
         msg = _(b'parsing obsolete marker: unknown version %r') % diskversion
         raise error.UnknownVersion(msg, version=diskversion)
     return diskversion, formats[diskversion][0](data, off, stop)
 
 
 def encodeheader(version=_fm0version):
     return _pack(b'>B', version)
 
 
 def encodemarkers(markers, addheader=False, version=_fm0version):
     # Kept separate from flushmarkers(), it will be reused for
     # markers exchange.
     encodeone = formats[version][1]
     if addheader:
         yield encodeheader(version)
     for marker in markers:
         yield encodeone(marker)
 
 
 @util.nogc
 def _addsuccessors(successors, markers):
     for mark in markers:
         successors.setdefault(mark[0], set()).add(mark)
 
 
 @util.nogc
 def _addpredecessors(predecessors, markers):
     for mark in markers:
         for suc in mark[1]:
             predecessors.setdefault(suc, set()).add(mark)
 
 
 @util.nogc
 def _addchildren(children, markers):
     for mark in markers:
         parents = mark[5]
         if parents is not None:
             for p in parents:
                 children.setdefault(p, set()).add(mark)
 
 
 def _checkinvalidmarkers(repo, markers):
     """search for marker with invalid data and raise error if needed
 
     Exist as a separated function to allow the evolve extension for a more
     subtle handling.
     """
     for mark in markers:
         if repo.nullid in mark[1]:
             raise error.Abort(
                 _(
                     b'bad obsolescence marker detected: '
                     b'invalid successors nullid'
                 )
             )
 
 
 class obsstore:
     """Store obsolete markers
 
     Markers can be accessed with two mappings:
     - predecessors[x] -> set(markers on predecessors edges of x)
     - successors[x] -> set(markers on successors edges of x)
     - children[x]   -> set(markers on predecessors edges of children(x)
     """
 
     fields = (b'prec', b'succs', b'flag', b'meta', b'date', b'parents')
     # prec:    nodeid, predecessors changesets
     # succs:   tuple of nodeid, successor changesets (0-N length)
     # flag:    integer, flag field carrying modifier for the markers (see doc)
     # meta:    binary blob in UTF-8, encoded metadata dictionary
     # date:    (float, int) tuple, date of marker creation
     # parents: (tuple of nodeid) or None, parents of predecessors
     #          None is used when no data has been recorded
 
     def __init__(self, repo, svfs, defaultformat=_fm1version, readonly=False):
         # caches for various obsolescence related cache
         self.caches = {}
         self.svfs = svfs
         self._repo = weakref.ref(repo)
         self._defaultformat = defaultformat
         self._readonly = readonly
 
     @property
     def repo(self):
         r = self._repo()
         if r is None:
             msg = "using the obsstore of a deallocated repo"
             raise error.ProgrammingError(msg)
         return r
 
     def __iter__(self):
         return iter(self._all)
 
     def __len__(self):
         return len(self._all)
 
     def __nonzero__(self):
         from . import statichttprepo
 
         if isinstance(self.repo, statichttprepo.statichttprepository):
             # If repo is accessed via static HTTP, then we can't use os.stat()
             # to just peek at the file size.
             return len(self._data) > 1
         if not self._cached('_all'):
             try:
                 return self.svfs.stat(b'obsstore').st_size > 1
             except FileNotFoundError:
                 # just build an empty _all list if no obsstore exists, which
                 # avoids further stat() syscalls
                 pass
         return bool(self._all)
 
     __bool__ = __nonzero__
 
     @property
     def readonly(self):
         """True if marker creation is disabled
 
         Remove me in the future when obsolete marker is always on."""
         return self._readonly
 
     def create(
         self,
         transaction,
         prec,
         succs=(),
         flag=0,
         parents=None,
         date=None,
         metadata=None,
         ui=None,
     ):
         """obsolete: add a new obsolete marker
 
         * ensuring it is hashable
         * check mandatory metadata
         * encode metadata
 
         If you are a human writing code creating marker you want to use the
         `createmarkers` function in this module instead.
 
         return True if a new marker have been added, False if the markers
         already existed (no op).
         """
         flag = int(flag)
         if metadata is None:
             metadata = {}
         if date is None:
             if b'date' in metadata:
                 # as a courtesy for out-of-tree extensions
                 date = dateutil.parsedate(metadata.pop(b'date'))
             elif ui is not None:
                 date = ui.configdate(b'devel', b'default-date')
                 if date is None:
                     date = dateutil.makedate()
             else:
                 date = dateutil.makedate()
         if flag & usingsha256:
             if len(prec) != 32:
                 raise ValueError(prec)
             for succ in succs:
                 if len(succ) != 32:
                     raise ValueError(succ)
         else:
             if len(prec) != 20:
                 raise ValueError(prec)
             for succ in succs:
                 if len(succ) != 20:
                     raise ValueError(succ)
         if prec in succs:
             raise ValueError('in-marker cycle with %s' % prec.hex())
 
         metadata = tuple(sorted(metadata.items()))
         for k, v in metadata:
             try:
                 # might be better to reject non-ASCII keys
                 k.decode('utf-8')
                 v.decode('utf-8')
             except UnicodeDecodeError:
                 raise error.ProgrammingError(
                     b'obsstore metadata must be valid UTF-8 sequence '
                     b'(key = %r, value = %r)'
                     % (pycompat.bytestr(k), pycompat.bytestr(v))
                 )
 
         marker = (bytes(prec), tuple(succs), flag, metadata, date, parents)
         return bool(self.add(transaction, [marker]))
 
     def add(self, transaction, markers):
         """Add new markers to the store
 
         Take care of filtering duplicate.
         Return the number of new marker."""
         if self._readonly:
             raise error.Abort(
                 _(b'creating obsolete markers is not enabled on this repo')
             )
         known = set()
         getsuccessors = self.successors.get
         new = []
         for m in markers:
             if m not in getsuccessors(m[0], ()) and m not in known:
                 known.add(m)
                 new.append(m)
         if new:
             f = self.svfs(b'obsstore', b'ab')
             try:
                 offset = f.tell()
                 transaction.add(b'obsstore', offset)
                 # offset == 0: new file - add the version header
                 data = b''.join(encodemarkers(new, offset == 0, self._version))
                 f.write(data)
             finally:
                 # XXX: f.close() == filecache invalidation == obsstore rebuilt.
                 # call 'filecacheentry.refresh()'  here
                 f.close()
             addedmarkers = transaction.changes.get(b'obsmarkers')
             if addedmarkers is not None:
                 addedmarkers.update(new)
             self._addmarkers(new, data)
             # new marker *may* have changed several set. invalidate the cache.
             self.caches.clear()
         # records the number of new markers for the transaction hooks
         previous = int(transaction.hookargs.get(b'new_obsmarkers', b'0'))
         transaction.hookargs[b'new_obsmarkers'] = b'%d' % (previous + len(new))
         return len(new)
 
     def mergemarkers(self, transaction, data):
         """merge a binary stream of markers inside the obsstore
 
         Returns the number of new markers added."""
         version, markers = _readmarkers(data)
         return self.add(transaction, markers)
 
     @propertycache
     def _data(self):
         return self.svfs.tryread(b'obsstore')
 
     @propertycache
     def _version(self):
         if len(self._data) >= 1:
             return _readmarkerversion(self._data)
         else:
             return self._defaultformat
 
     @propertycache
     def _all(self):
         data = self._data
         if not data:
             return []
         self._version, markers = _readmarkers(data)
         markers = list(markers)
         _checkinvalidmarkers(self.repo, markers)
         return markers
 
     @propertycache
     def successors(self):
         successors = {}
         _addsuccessors(successors, self._all)
         return successors
 
     @propertycache
     def predecessors(self):
         predecessors = {}
         _addpredecessors(predecessors, self._all)
         return predecessors
 
     @propertycache
     def children(self):
         children = {}
         _addchildren(children, self._all)
         return children
 
     def _cached(self, attr):
         return attr in self.__dict__
 
     def _addmarkers(self, markers, rawdata):
         markers = list(markers)  # to allow repeated iteration
         self._data = self._data + rawdata
         self._all.extend(markers)
         if self._cached('successors'):
             _addsuccessors(self.successors, markers)
         if self._cached('predecessors'):
             _addpredecessors(self.predecessors, markers)
         if self._cached('children'):
             _addchildren(self.children, markers)
         _checkinvalidmarkers(self.repo, markers)
 
-    def relevantmarkers(self, nodes):
-        """return a set of all obsolescence markers relevant to a set of nodes.
+    def relevantmarkers(self, nodes=None, revs=None):
+        """return a set of all obsolescence markers relevant to a set of
+        nodes or revisions.
 
-        "relevant" to a set of nodes mean:
+        "relevant" to a set of nodes or revisions mean:
 
         - marker that use this changeset as successor
         - prune marker of direct children on this changeset
         - recursive application of the two rules on predecessors of these
           markers
 
         It is a set so you cannot rely on order."""
+        if nodes is None:
+            nodes = set()
+        if revs is None:
+            revs = set()
 
-        pendingnodes = set(nodes)
-        seenmarkers = set()
-        seennodes = set(pendingnodes)
+        tonode = self.repo.unfiltered().changelog.node
+        pendingnodes = set()
         precursorsmarkers = self.predecessors
         succsmarkers = self.successors
         children = self.children
+        for node in nodes:
+            if (
+                node in precursorsmarkers
+                or node in succsmarkers
+                or node in children
+            ):
+                pendingnodes.add(node)
+        for rev in revs:
+            node = tonode(rev)
+            if (
+                node in precursorsmarkers
+                or node in succsmarkers
+                or node in children
+            ):
+                pendingnodes.add(node)
+        seenmarkers = set()
+        seennodes = pendingnodes.copy()
         while pendingnodes:
             direct = set()
             for current in pendingnodes:
                 direct.update(precursorsmarkers.get(current, ()))
                 pruned = [m for m in children.get(current, ()) if not m[1]]
                 direct.update(pruned)
                 pruned = [m for m in succsmarkers.get(current, ()) if not m[1]]
                 direct.update(pruned)
             direct -= seenmarkers
             pendingnodes = {m[0] for m in direct}
             seenmarkers |= direct
             pendingnodes -= seennodes
             seennodes |= pendingnodes
         return seenmarkers
 
 
 def makestore(ui, repo):
     """Create an obsstore instance from a repo."""
     # read default format for new obsstore.
     # developer config: format.obsstore-version
     defaultformat = ui.configint(b'format', b'obsstore-version')
     # rely on obsstore class default when possible.
     kwargs = {}
     if defaultformat is not None:
         kwargs['defaultformat'] = defaultformat
     readonly = not isenabled(repo, createmarkersopt)
     store = obsstore(repo, repo.svfs, readonly=readonly, **kwargs)
     if store and readonly:
         ui.warn(
             _(b'"obsolete" feature not enabled but %i markers found!\n')
             % len(list(store))
         )
     return store
 
 
 def commonversion(versions):
     """Return the newest version listed in both versions and our local formats.
 
     Returns None if no common version exists.
     """
     versions.sort(reverse=True)
     # search for highest version known on both side
     for v in versions:
         if v in formats:
             return v
     return None
 
 
 # arbitrary picked to fit into 8K limit from HTTP server
 # you have to take in account:
 # - the version header
 # - the base85 encoding
 _maxpayload = 5300
 
 
 def _pushkeyescape(markers):
     """encode markers into a dict suitable for pushkey exchange
 
     - binary data is base85 encoded
     - split in chunks smaller than 5300 bytes"""
     keys = {}
     parts = []
     currentlen = _maxpayload * 2  # ensure we create a new part
     for marker in markers:
         nextdata = _fm0encodeonemarker(marker)
         if len(nextdata) + currentlen > _maxpayload:
             currentpart = []
             currentlen = 0
             parts.append(currentpart)
         currentpart.append(nextdata)
         currentlen += len(nextdata)
     for idx, part in enumerate(reversed(parts)):
         data = b''.join([_pack(b'>B', _fm0version)] + part)
         keys[b'dump%i' % idx] = util.b85encode(data)
     return keys
 
 
 def listmarkers(repo):
     """List markers over pushkey"""
     if not repo.obsstore:
         return {}
     return _pushkeyescape(sorted(repo.obsstore))
 
 
 def pushmarker(repo, key, old, new):
     """Push markers over pushkey"""
     if not key.startswith(b'dump'):
         repo.ui.warn(_(b'unknown key: %r') % key)
         return False
     if old:
         repo.ui.warn(_(b'unexpected old value for %r') % key)
         return False
     data = util.b85decode(new)
     with repo.lock(), repo.transaction(b'pushkey: obsolete markers') as tr:
         repo.obsstore.mergemarkers(tr, data)
         repo.invalidatevolatilesets()
         return True
 
 
 # mapping of 'set-name' -> <function to compute this set>
 cachefuncs = {}
 
 
 def cachefor(name):
     """Decorator to register a function as computing the cache for a set"""
 
     def decorator(func):
         if name in cachefuncs:
             msg = b"duplicated registration for volatileset '%s' (existing: %r)"
             raise error.ProgrammingError(msg % (name, cachefuncs[name]))
         cachefuncs[name] = func
         return func
 
     return decorator
 
 
 def getrevs(repo, name):
     """Return the set of revision that belong to the <name> set
 
     Such access may compute the set and cache it for future use"""
     repo = repo.unfiltered()
     with util.timedcm('getrevs %s', name):
         if not repo.obsstore:
             return frozenset()
         if name not in repo.obsstore.caches:
             repo.obsstore.caches[name] = cachefuncs[name](repo)
         return repo.obsstore.caches[name]
 
 
 # To be simple we need to invalidate obsolescence cache when:
 #
 # - new changeset is added:
 # - public phase is changed
 # - obsolescence marker are added
 # - strip is used a repo
 def clearobscaches(repo):
     """Remove all obsolescence related cache from a repo
 
     This remove all cache in obsstore is the obsstore already exist on the
     repo.
 
     (We could be smarter here given the exact event that trigger the cache
     clearing)"""
     # only clear cache is there is obsstore data in this repo
     if b'obsstore' in repo._filecache:
         repo.obsstore.caches.clear()
 
 
 def _mutablerevs(repo):
     """the set of mutable revision in the repository"""
     return repo._phasecache.getrevset(repo, phases.relevant_mutable_phases)
 
 
 @cachefor(b'obsolete')
 def _computeobsoleteset(repo):
     """the set of obsolete revisions"""
     getnode = repo.changelog.node
     notpublic = _mutablerevs(repo)
     isobs = repo.obsstore.successors.__contains__
     return frozenset(r for r in notpublic if isobs(getnode(r)))
 
 
 @cachefor(b'orphan')
 def _computeorphanset(repo):
     """the set of non obsolete revisions with obsolete parents"""
     pfunc = repo.changelog.parentrevs
     mutable = _mutablerevs(repo)
     obsolete = getrevs(repo, b'obsolete')
     others = mutable - obsolete
     unstable = set()
     for r in sorted(others):
         # A rev is unstable if one of its parent is obsolete or unstable
         # this works since we traverse following growing rev order
         for p in pfunc(r):
             if p in obsolete or p in unstable:
                 unstable.add(r)
                 break
     return frozenset(unstable)
 
 
 @cachefor(b'suspended')
 def _computesuspendedset(repo):
     """the set of obsolete parents with non obsolete descendants"""
     suspended = repo.changelog.ancestors(getrevs(repo, b'orphan'))
     return frozenset(r for r in getrevs(repo, b'obsolete') if r in suspended)
 
 
 @cachefor(b'extinct')
 def _computeextinctset(repo):
     """the set of obsolete parents without non obsolete descendants"""
     return getrevs(repo, b'obsolete') - getrevs(repo, b'suspended')
 
 
 @cachefor(b'phasedivergent')
 def _computephasedivergentset(repo):
     """the set of revs trying to obsolete public revisions"""
     bumped = set()
     # util function (avoid attribute lookup in the loop)
     phase = repo._phasecache.phase  # would be faster to grab the full list
     public = phases.public
     cl = repo.changelog
     torev = cl.index.get_rev
     tonode = cl.node
     obsstore = repo.obsstore
     candidates = sorted(_mutablerevs(repo) - getrevs(repo, b"obsolete"))
     for rev in candidates:
         # We only evaluate mutable, non-obsolete revision
         node = tonode(rev)
         # (future) A cache of predecessors may worth if split is very common
         for pnode in obsutil.allpredecessors(
             obsstore, [node], ignoreflags=bumpedfix
         ):
             prev = torev(pnode)  # unfiltered! but so is phasecache
             if (prev is not None) and (phase(repo, prev) <= public):
                 # we have a public predecessor
                 bumped.add(rev)
                 break  # Next draft!
     return frozenset(bumped)
 
 
 @cachefor(b'contentdivergent')
 def _computecontentdivergentset(repo):
     """the set of rev that compete to be the final successors of some revision."""
     divergent = set()
     obsstore = repo.obsstore
     newermap = {}
     tonode = repo.changelog.node
     candidates = sorted(_mutablerevs(repo) - getrevs(repo, b"obsolete"))
     for rev in candidates:
         node = tonode(rev)
         mark = obsstore.predecessors.get(node, ())
         toprocess = set(mark)
         seen = set()
         while toprocess:
             prec = toprocess.pop()[0]
             if prec in seen:
                 continue  # emergency cycle hanging prevention
             seen.add(prec)
             if prec not in newermap:
                 obsutil.successorssets(repo, prec, cache=newermap)
             newer = [n for n in newermap[prec] if n]
             if len(newer) > 1:
                 divergent.add(rev)
                 break
             toprocess.update(obsstore.predecessors.get(prec, ()))
     return frozenset(divergent)
 
 
 def makefoldid(relation, user):
     folddigest = hashutil.sha1(user)
     for p in relation[0] + relation[1]:
         folddigest.update(b'%d' % p.rev())
         folddigest.update(p.node())
     # Since fold only has to compete against fold for the same successors, it
     # seems fine to use a small ID. Smaller ID save space.
     return hex(folddigest.digest())[:8]
 
 
 def createmarkers(
     repo, relations, flag=0, date=None, metadata=None, operation=None
 ):
     """Add obsolete markers between changesets in a repo
 
     <relations> must be an iterable of ((<old>,...), (<new>, ...)[,{metadata}])
     tuple. `old` and `news` are changectx. metadata is an optional dictionary
     containing metadata for this marker only. It is merged with the global
     metadata specified through the `metadata` argument of this function.
     Any string values in metadata must be UTF-8 bytes.
 
     Trying to obsolete a public changeset will raise an exception.
 
     Current user and date are used except if specified otherwise in the
     metadata attribute.
 
     This function operates within a transaction of its own, but does
     not take any lock on the repo.
     """
     # prepare metadata
     if metadata is None:
         metadata = {}
     if b'user' not in metadata:
         luser = (
             repo.ui.config(b'devel', b'user.obsmarker') or repo.ui.username()
         )
         metadata[b'user'] = encoding.fromlocal(luser)
 
     # Operation metadata handling
     useoperation = repo.ui.configbool(
         b'experimental', b'evolution.track-operation'
     )
     if useoperation and operation:
         metadata[b'operation'] = operation
 
     # Effect flag metadata handling
     saveeffectflag = repo.ui.configbool(
         b'experimental', b'evolution.effect-flags'
     )
 
     with repo.transaction(b'add-obsolescence-marker') as tr:
         markerargs = []
         for rel in relations:
             predecessors = rel[0]
             if not isinstance(predecessors, tuple):
                 # preserve compat with old API until all caller are migrated
                 predecessors = (predecessors,)
             if len(predecessors) > 1 and len(rel[1]) != 1:
                 msg = b'Fold markers can only have 1 successors, not %d'
                 raise error.ProgrammingError(msg % len(rel[1]))
             foldid = None
             foldsize = len(predecessors)
             if 1 < foldsize:
                 foldid = makefoldid(rel, metadata[b'user'])
             for foldidx, prec in enumerate(predecessors, 1):
                 sucs = rel[1]
                 localmetadata = metadata.copy()
                 if len(rel) > 2:
                     localmetadata.update(rel[2])
                 if foldid is not None:
                     localmetadata[b'fold-id'] = foldid
                     localmetadata[b'fold-idx'] = b'%d' % foldidx
                     localmetadata[b'fold-size'] = b'%d' % foldsize
 
                 if not prec.mutable():
                     raise error.Abort(
                         _(b"cannot obsolete public changeset: %s") % prec,
                         hint=b"see 'hg help phases' for details",
                     )
                 nprec = prec.node()
                 nsucs = tuple(s.node() for s in sucs)
                 npare = None
                 if not nsucs:
                     npare = tuple(p.node() for p in prec.parents())
                 if nprec in nsucs:
                     raise error.Abort(
                         _(b"changeset %s cannot obsolete itself") % prec
                     )
 
                 # Effect flag can be different by relation
                 if saveeffectflag:
                     # The effect flag is saved in a versioned field name for
                     # future evolution
                     effectflag = obsutil.geteffectflag(prec, sucs)
                     localmetadata[obsutil.EFFECTFLAGFIELD] = b"%d" % effectflag
 
                 # Creating the marker causes the hidden cache to become
                 # invalid, which causes recomputation when we ask for
                 # prec.parents() above.  Resulting in n^2 behavior.  So let's
                 # prepare all of the args first, then create the markers.
                 markerargs.append((nprec, nsucs, npare, localmetadata))
 
         for args in markerargs:
             nprec, nsucs, npare, localmetadata = args
             repo.obsstore.create(
                 tr,
                 nprec,
                 nsucs,
                 flag,
                 parents=npare,
                 date=date,
                 metadata=localmetadata,
                 ui=repo.ui,
             )
             repo.filteredrevcache.clear()

mercurial/obsutil.py

@@ -1,1049 +1,1049
 # obsutil.py - utility functions for obsolescence
 #
 # Copyright 2017 Boris Feld <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
 from __future__ import annotations
 
 import re
 
 from .i18n import _
 from .node import (
     hex,
     short,
 )
 from . import (
     diffutil,
     encoding,
     error,
     phases,
     util,
 )
 from .utils import dateutil
 
 ### obsolescence marker flag
 
 ## bumpedfix flag
 #
 # When a changeset A' succeed to a changeset A which became public, we call A'
 # "bumped" because it's a successors of a public changesets
 #
 # o    A' (bumped)
 # |`:
 # | o  A
 # |/
 # o    Z
 #
 # The way to solve this situation is to create a new changeset Ad as children
 # of A. This changeset have the same content than A'. So the diff from A to A'
 # is the same than the diff from A to Ad. Ad is marked as a successors of A'
 #
 # o   Ad
 # |`:
 # | x A'
 # |'|
 # o | A
 # |/
 # o Z
 #
 # But by transitivity Ad is also a successors of A. To avoid having Ad marked
 # as bumped too, we add the `bumpedfix` flag to the marker. <A', (Ad,)>.
 # This flag mean that the successors express the changes between the public and
 # bumped version and fix the situation, breaking the transitivity of
 # "bumped" here.
 bumpedfix = 1
 usingsha256 = 2
 
 
 class marker:
     """Wrap obsolete marker raw data"""
 
     def __init__(self, repo, data):
         # the repo argument will be used to create changectx in later version
         self._repo = repo
         self._data = data
         self._decodedmeta = None
 
     def __hash__(self):
         return hash(self._data)
 
     def __eq__(self, other):
         if type(other) != type(self):
             return False
         return self._data == other._data
 
     def prednode(self):
         """Predecessor changeset node identifier"""
         return self._data[0]
 
     def succnodes(self):
         """List of successor changesets node identifiers"""
         return self._data[1]
 
     def parentnodes(self):
         """Parents of the predecessors (None if not recorded)"""
         return self._data[5]
 
     def metadata(self):
         """Decoded metadata dictionary"""
         return dict(self._data[3])
 
     def date(self):
         """Creation date as (unixtime, offset)"""
         return self._data[4]
 
     def flags(self):
         """The flags field of the marker"""
         return self._data[2]
 
 
 def getmarkers(repo, nodes=None, exclusive=False):
     """returns markers known in a repository
 
     If <nodes> is specified, only markers "relevant" to those nodes are are
     returned"""
     if nodes is None:
         rawmarkers = repo.obsstore
     elif exclusive:
         rawmarkers = exclusivemarkers(repo, nodes)
     else:
-        rawmarkers = repo.obsstore.relevantmarkers(nodes)
+        rawmarkers = repo.obsstore.relevantmarkers(nodes=nodes)
 
     for markerdata in rawmarkers:
         yield marker(repo, markerdata)
 
 
 def sortedmarkers(markers):
     # last item of marker tuple ('parents') may be None or a tuple
     return sorted(markers, key=lambda m: m[:-1] + (m[-1] or (),))
 
 
 def closestpredecessors(repo, nodeid):
     """yield the list of next predecessors pointing on visible changectx nodes
 
     This function respect the repoview filtering, filtered revision will be
     considered missing.
     """
 
     precursors = repo.obsstore.predecessors
     stack = [nodeid]
     seen = set(stack)
 
     while stack:
         current = stack.pop()
         currentpreccs = precursors.get(current, ())
 
         for prec in currentpreccs:
             precnodeid = prec[0]
 
             # Basic cycle protection
             if precnodeid in seen:
                 continue
             seen.add(precnodeid)
 
             if precnodeid in repo:
                 yield precnodeid
             else:
                 stack.append(precnodeid)
 
 
 def allpredecessors(obsstore, nodes, ignoreflags=0):
     """Yield node for every precursors of <nodes>.
 
     Some precursors may be unknown locally.
 
     This is a linear yield unsuited to detecting folded changesets. It includes
     initial nodes too."""
 
     remaining = set(nodes)
     seen = set(remaining)
     prec = obsstore.predecessors.get
     while remaining:
         current = remaining.pop()
         yield current
         for mark in prec(current, ()):
             # ignore marker flagged with specified flag
             if mark[2] & ignoreflags:
                 continue
             suc = mark[0]
             if suc not in seen:
                 seen.add(suc)
                 remaining.add(suc)
 
 
 def allsuccessors(obsstore, nodes, ignoreflags=0):
     """Yield node for every successor of <nodes>.
 
     Some successors may be unknown locally.
 
     This is a linear yield unsuited to detecting split changesets. It includes
     initial nodes too."""
     remaining = set(nodes)
     seen = set(remaining)
     while remaining:
         current = remaining.pop()
         yield current
         for mark in obsstore.successors.get(current, ()):
             # ignore marker flagged with specified flag
             if mark[2] & ignoreflags:
                 continue
             for suc in mark[1]:
                 if suc not in seen:
                     seen.add(suc)
                     remaining.add(suc)
 
 
 def _filterprunes(markers):
     """return a set with no prune markers"""
     return {m for m in markers if m[1]}
 
 
 def exclusivemarkers(repo, nodes):
     """set of markers relevant to "nodes" but no other locally-known nodes
 
     This function compute the set of markers "exclusive" to a locally-known
     node. This means we walk the markers starting from <nodes> until we reach a
     locally-known precursors outside of <nodes>. Element of <nodes> with
     locally-known successors outside of <nodes> are ignored (since their
     precursors markers are also relevant to these successors).
 
     For example:
 
         # (A0 rewritten as A1)
         #
         # A0 <-1- A1 # Marker "1" is exclusive to A1
 
         or
 
         # (A0 rewritten as AX; AX rewritten as A1; AX is unknown locally)
         #
         # <-1- A0 <-2- AX <-3- A1 # Marker "2,3" are exclusive to A1
 
         or
 
         # (A0 has unknown precursors, A0 rewritten as A1 and A2 (divergence))
         #
         #          <-2- A1 # Marker "2" is exclusive to A0,A1
         #        /
         # <-1- A0
         #        \
         #         <-3- A2 # Marker "3" is exclusive to A0,A2
         #
         # in addition:
         #
         #  Markers "2,3" are exclusive to A1,A2
         #  Markers "1,2,3" are exclusive to A0,A1,A2
 
         See test/test-obsolete-bundle-strip.t for more examples.
 
     An example usage is strip. When stripping a changeset, we also want to
     strip the markers exclusive to this changeset. Otherwise we would have
     "dangling"" obsolescence markers from its precursors: Obsolescence markers
     marking a node as obsolete without any successors available locally.
 
     As for relevant markers, the prune markers for children will be followed.
     Of course, they will only be followed if the pruned children is
     locally-known. Since the prune markers are relevant to the pruned node.
     However, while prune markers are considered relevant to the parent of the
     pruned changesets, prune markers for locally-known changeset (with no
     successors) are considered exclusive to the pruned nodes. This allows
     to strip the prune markers (with the rest of the exclusive chain) alongside
     the pruned changesets.
     """
     # running on a filtered repository would be dangerous as markers could be
     # reported as exclusive when they are relevant for other filtered nodes.
     unfi = repo.unfiltered()
 
     # shortcut to various useful item
     has_node = unfi.changelog.index.has_node
     precursorsmarkers = unfi.obsstore.predecessors
     successormarkers = unfi.obsstore.successors
     childrenmarkers = unfi.obsstore.children
 
     # exclusive markers (return of the function)
     exclmarkers = set()
     # we need fast membership testing
     nodes = set(nodes)
     # looking for head in the obshistory
     #
     # XXX we are ignoring all issues in regard with cycle for now.
     stack = [n for n in nodes if not _filterprunes(successormarkers.get(n, ()))]
     stack.sort()
     # nodes already stacked
     seennodes = set(stack)
     while stack:
         current = stack.pop()
         # fetch precursors markers
         markers = list(precursorsmarkers.get(current, ()))
         # extend the list with prune markers
         for mark in successormarkers.get(current, ()):
             if not mark[1]:
                 markers.append(mark)
         # and markers from children (looking for prune)
         for mark in childrenmarkers.get(current, ()):
             if not mark[1]:
                 markers.append(mark)
         # traverse the markers
         for mark in markers:
             if mark in exclmarkers:
                 # markers already selected
                 continue
 
             # If the markers is about the current node, select it
             #
             # (this delay the addition of markers from children)
             if mark[1] or mark[0] == current:
                 exclmarkers.add(mark)
 
             # should we keep traversing through the precursors?
             prec = mark[0]
 
             # nodes in the stack or already processed
             if prec in seennodes:
                 continue
 
             # is this a locally known node ?
             known = has_node(prec)
             # if locally-known and not in the <nodes> set the traversal
             # stop here.
             if known and prec not in nodes:
                 continue
 
             # do not keep going if there are unselected markers pointing to this
             # nodes. If we end up traversing these unselected markers later the
             # node will be taken care of at that point.
             precmarkers = _filterprunes(successormarkers.get(prec))
             if precmarkers.issubset(exclmarkers):
                 seennodes.add(prec)
                 stack.append(prec)
 
     return exclmarkers
 
 
 def foreground(repo, nodes):
     """return all nodes in the "foreground" of other node
 
     The foreground of a revision is anything reachable using parent -> children
     or precursor -> successor relation. It is very similar to "descendant" but
     augmented with obsolescence information.
 
     Beware that possible obsolescence cycle may result if complex situation.
     """
     repo = repo.unfiltered()
     foreground = set(repo.set(b'%ln::', nodes))
     if repo.obsstore:
         # We only need this complicated logic if there is obsolescence
         # XXX will probably deserve an optimised revset.
         has_node = repo.changelog.index.has_node
         plen = -1
         # compute the whole set of successors or descendants
         while len(foreground) != plen:
             plen = len(foreground)
             succs = {c.node() for c in foreground}
             mutable = [c.node() for c in foreground if c.mutable()]
             succs.update(allsuccessors(repo.obsstore, mutable))
             known = (n for n in succs if has_node(n))
             foreground = set(repo.set(b'%ln::', known))
     return {c.node() for c in foreground}
 
 
 # effectflag field
 #
 # Effect-flag is a 1-byte bit field used to store what changed between a
 # changeset and its successor(s).
 #
 # The effect flag is stored in obs-markers metadata while we iterate on the
 # information design. That's why we have the EFFECTFLAGFIELD. If we come up
 # with an incompatible design for effect flag, we can store a new design under
 # another field name so we don't break readers. We plan to extend the existing
 # obsmarkers bit-field when the effect flag design will be stabilized.
 #
 # The effect-flag is placed behind an experimental flag
 # `effect-flags` set to off by default.
 #
 
 EFFECTFLAGFIELD = b"ef1"
 
 DESCCHANGED = 1 << 0  # action changed the description
 METACHANGED = 1 << 1  # action change the meta
 DIFFCHANGED = 1 << 3  # action change diff introduced by the changeset
 PARENTCHANGED = 1 << 2  # action change the parent
 USERCHANGED = 1 << 4  # the user changed
 DATECHANGED = 1 << 5  # the date changed
 BRANCHCHANGED = 1 << 6  # the branch changed
 
 METABLACKLIST = [
     re.compile(b'^branch$'),
     re.compile(b'^.*-source$'),
     re.compile(b'^.*_source$'),
     re.compile(b'^source$'),
 ]
 
 
 def metanotblacklisted(metaitem):
     """Check that the key of a meta item (extrakey, extravalue) does not
     match at least one of the blacklist pattern
     """
     metakey = metaitem[0]
 
     return not any(pattern.match(metakey) for pattern in METABLACKLIST)
 
 
 def _prepare_hunk(hunk):
     """Drop all information but the username and patch"""
     cleanhunk = []
     for line in hunk.splitlines():
         if line.startswith(b'# User') or not line.startswith(b'#'):
             if line.startswith(b'@@'):
                 line = b'@@\n'
             cleanhunk.append(line)
     return cleanhunk
 
 
 def _getdifflines(iterdiff):
     """return a cleaned up lines"""
     lines = next(iterdiff, None)
 
     if lines is None:
         return lines
 
     return _prepare_hunk(lines)
 
 
 def _cmpdiff(leftctx, rightctx):
     """return True if both ctx introduce the "same diff"
 
     This is a first and basic implementation, with many shortcoming.
     """
     diffopts = diffutil.diffallopts(leftctx.repo().ui, {b'git': True})
 
     # Leftctx or right ctx might be filtered, so we need to use the contexts
     # with an unfiltered repository to safely compute the diff
 
     # leftctx and rightctx can be from different repository views in case of
     # hgsubversion, do don't try to access them from same repository
     # rightctx.repo() and leftctx.repo() are not always the same
     leftunfi = leftctx._repo.unfiltered()[leftctx.rev()]
     leftdiff = leftunfi.diff(opts=diffopts)
     rightunfi = rightctx._repo.unfiltered()[rightctx.rev()]
     rightdiff = rightunfi.diff(opts=diffopts)
 
     left, right = (0, 0)
     while None not in (left, right):
         left = _getdifflines(leftdiff)
         right = _getdifflines(rightdiff)
 
         if left != right:
             return False
     return True
 
 
 def geteffectflag(source, successors):
     """From an obs-marker relation, compute what changed between the
     predecessor and the successor.
     """
     effects = 0
 
     for changectx in successors:
         # Check if description has changed
         if changectx.description() != source.description():
             effects |= DESCCHANGED
 
         # Check if user has changed
         if changectx.user() != source.user():
             effects |= USERCHANGED
 
         # Check if date has changed
         if changectx.date() != source.date():
             effects |= DATECHANGED
 
         # Check if branch has changed
         if changectx.branch() != source.branch():
             effects |= BRANCHCHANGED
 
         # Check if at least one of the parent has changed
         if changectx.parents() != source.parents():
             effects |= PARENTCHANGED
 
         # Check if other meta has changed
         changeextra = changectx.extra().items()
         ctxmeta = sorted(filter(metanotblacklisted, changeextra))
 
         sourceextra = source.extra().items()
         srcmeta = sorted(filter(metanotblacklisted, sourceextra))
 
         if ctxmeta != srcmeta:
             effects |= METACHANGED
 
         # Check if the diff has changed
         if not _cmpdiff(source, changectx):
             effects |= DIFFCHANGED
 
     return effects
 
 
 def getobsoleted(repo, tr=None, changes=None):
     """return the set of pre-existing revisions obsoleted by a transaction
 
     Either the transaction or changes item of the transaction (for hooks)
     must be provided, but not both.
     """
     if (tr is None) == (changes is None):
         e = b"exactly one of tr and changes must be provided"
         raise error.ProgrammingError(e)
     torev = repo.unfiltered().changelog.index.get_rev
     phase = repo._phasecache.phase
     succsmarkers = repo.obsstore.successors.get
     public = phases.public
     if changes is None:
         changes = tr.changes
     addedmarkers = changes[b'obsmarkers']
     origrepolen = changes[b'origrepolen']
     seenrevs = set()
     obsoleted = set()
     for mark in addedmarkers:
         node = mark[0]
         rev = torev(node)
         if rev is None or rev in seenrevs or rev >= origrepolen:
             continue
         seenrevs.add(rev)
         if phase(repo, rev) == public:
             continue
         if set(succsmarkers(node) or []).issubset(addedmarkers):
             obsoleted.add(rev)
     return obsoleted
 
 
 class _succs(list):
     """small class to represent a successors with some metadata about it"""
 
     def __init__(self, *args, **kwargs):
         super(_succs, self).__init__(*args, **kwargs)
         self.markers = set()
 
     def copy(self):
         new = _succs(self)
         new.markers = self.markers.copy()
         return new
 
     @util.propertycache
     def _set(self):
         # immutable
         return set(self)
 
     def canmerge(self, other):
         return self._set.issubset(other._set)
 
 
 def successorssets(repo, initialnode, closest=False, cache=None):
     """Return set of all latest successors of initial nodes
 
     The successors set of a changeset A are the group of revisions that succeed
     A. It succeeds A as a consistent whole, each revision being only a partial
     replacement. By default, the successors set contains non-obsolete
     changesets only, walking the obsolescence graph until reaching a leaf. If
     'closest' is set to True, closest successors-sets are return (the
     obsolescence walk stops on known changesets).
 
     This function returns the full list of successor sets which is why it
     returns a list of tuples and not just a single tuple. Each tuple is a valid
     successors set. Note that (A,) may be a valid successors set for changeset A
     (see below).
 
     In most cases, a changeset A will have a single element (e.g. the changeset
     A is replaced by A') in its successors set. Though, it is also common for a
     changeset A to have no elements in its successor set (e.g. the changeset
     has been pruned). Therefore, the returned list of successors sets will be
     [(A',)] or [], respectively.
 
     When a changeset A is split into A' and B', however, it will result in a
     successors set containing more than a single element, i.e. [(A',B')].
     Divergent changesets will result in multiple successors sets, i.e. [(A',),
     (A'')].
 
     If a changeset A is not obsolete, then it will conceptually have no
     successors set. To distinguish this from a pruned changeset, the successor
     set will contain itself only, i.e. [(A,)].
 
     Finally, final successors unknown locally are considered to be pruned
     (pruned: obsoleted without any successors). (Final: successors not affected
     by markers).
 
     The 'closest' mode respect the repoview filtering. For example, without
     filter it will stop at the first locally known changeset, with 'visible'
     filter it will stop on visible changesets).
 
     The optional `cache` parameter is a dictionary that may contains
     precomputed successors sets. It is meant to reuse the computation of a
     previous call to `successorssets` when multiple calls are made at the same
     time. The cache dictionary is updated in place. The caller is responsible
     for its life span. Code that makes multiple calls to `successorssets`
     *should* use this cache mechanism or risk a performance hit.
 
     Since results are different depending of the 'closest' most, the same cache
     cannot be reused for both mode.
     """
 
     succmarkers = repo.obsstore.successors
 
     # Stack of nodes we search successors sets for
     toproceed = [initialnode]
     # set version of above list for fast loop detection
     # element added to "toproceed" must be added here
     stackedset = set(toproceed)
     if cache is None:
         cache = {}
 
     # This while loop is the flattened version of a recursive search for
     # successors sets
     #
     # def successorssets(x):
     #    successors = directsuccessors(x)
     #    ss = [[]]
     #    for succ in directsuccessors(x):
     #        # product as in itertools cartesian product
     #        ss = product(ss, successorssets(succ))
     #    return ss
     #
     # But we can not use plain recursive calls here:
     # - that would blow the python call stack
     # - obsolescence markers may have cycles, we need to handle them.
     #
     # The `toproceed` list act as our call stack. Every node we search
     # successors set for are stacked there.
     #
     # The `stackedset` is set version of this stack used to check if a node is
     # already stacked. This check is used to detect cycles and prevent infinite
     # loop.
     #
     # successors set of all nodes are stored in the `cache` dictionary.
     #
     # After this while loop ends we use the cache to return the successors sets
     # for the node requested by the caller.
     while toproceed:
         # Every iteration tries to compute the successors sets of the topmost
         # node of the stack: CURRENT.
         #
         # There are four possible outcomes:
         #
         # 1) We already know the successors sets of CURRENT:
         #    -> mission accomplished, pop it from the stack.
         # 2) Stop the walk:
         #    default case: Node is not obsolete
         #    closest case: Node is known at this repo filter level
         #      -> the node is its own successors sets. Add it to the cache.
         # 3) We do not know successors set of direct successors of CURRENT:
         #    -> We add those successors to the stack.
         # 4) We know successors sets of all direct successors of CURRENT:
         #    -> We can compute CURRENT successors set and add it to the
         #       cache.
         #
         current = toproceed[-1]
 
         # case 2 condition is a bit hairy because of closest,
         # we compute it on its own
         case2condition = (current not in succmarkers) or (
             closest and current != initialnode and current in repo
         )
 
         if current in cache:
             # case (1): We already know the successors sets
             stackedset.remove(toproceed.pop())
         elif case2condition:
             # case (2): end of walk.
             if current in repo:
                 # We have a valid successors.
                 cache[current] = [_succs((current,))]
             else:
                 # Final obsolete version is unknown locally.
                 # Do not count that as a valid successors
                 cache[current] = []
         else:
             # cases (3) and (4)
             #
             # We proceed in two phases. Phase 1 aims to distinguish case (3)
             # from case (4):
             #
             #     For each direct successors of CURRENT, we check whether its
             #     successors sets are known. If they are not, we stack the
             #     unknown node and proceed to the next iteration of the while
             #     loop. (case 3)
             #
             #     During this step, we may detect obsolescence cycles: a node
             #     with unknown successors sets but already in the call stack.
             #     In such a situation, we arbitrary set the successors sets of
             #     the node to nothing (node pruned) to break the cycle.
             #
             #     If no break was encountered we proceed to phase 2.
             #
             # Phase 2 computes successors sets of CURRENT (case 4); see details
             # in phase 2 itself.
             #
             # Note the two levels of iteration in each phase.
             # - The first one handles obsolescence markers using CURRENT as
             #   precursor (successors markers of CURRENT).
             #
             #   Having multiple entry here means divergence.
             #
             # - The second one handles successors defined in each marker.
             #
             #   Having none means pruned node, multiple successors means split,
             #   single successors are standard replacement.
             #
             for mark in sortedmarkers(succmarkers[current]):
                 for suc in mark[1]:
                     if suc not in cache:
                         if suc in stackedset:
                             # cycle breaking
                             cache[suc] = []
                         else:
                             # case (3) If we have not computed successors sets
                             # of one of those successors we add it to the
                             # `toproceed` stack and stop all work for this
                             # iteration.
                             toproceed.append(suc)
                             stackedset.add(suc)
                             break
                 else:
                     continue
                 break
             else:
                 # case (4): we know all successors sets of all direct
                 # successors
                 #
                 # Successors set contributed by each marker depends on the
                 # successors sets of all its "successors" node.
                 #
                 # Each different marker is a divergence in the obsolescence
                 # history. It contributes successors sets distinct from other
                 # markers.
                 #
                 # Within a marker, a successor may have divergent successors
                 # sets. In such a case, the marker will contribute multiple
                 # divergent successors sets. If multiple successors have
                 # divergent successors sets, a Cartesian product is used.
                 #
                 # At the end we post-process successors sets to remove
                 # duplicated entry and successors set that are strict subset of
                 # another one.
                 succssets = []
                 for mark in sortedmarkers(succmarkers[current]):
                     # successors sets contributed by this marker
                     base = _succs()
                     base.markers.add(mark)
                     markss = [base]
                     for suc in mark[1]:
                         # cardinal product with previous successors
                         productresult = []
                         for prefix in markss:
                             for suffix in cache[suc]:
                                 newss = prefix.copy()
                                 newss.markers.update(suffix.markers)
                                 for part in suffix:
                                     # do not duplicated entry in successors set
                                     # first entry wins.
                                     if part not in newss:
                                         newss.append(part)
                                 productresult.append(newss)
                         if productresult:
                             markss = productresult
                     succssets.extend(markss)
                 # remove duplicated and subset
                 seen = []
                 final = []
                 candidates = sorted(
                     (s for s in succssets if s), key=len, reverse=True
                 )
                 for cand in candidates:
                     for seensuccs in seen:
                         if cand.canmerge(seensuccs):
                             seensuccs.markers.update(cand.markers)
                             break
                     else:
                         final.append(cand)
                         seen.append(cand)
                 final.reverse()  # put small successors set first
                 cache[current] = final
     return cache[initialnode]
 
 
 def successorsandmarkers(repo, ctx):
     """compute the raw data needed for computing obsfate
     Returns a list of dict, one dict per successors set
     """
     if not ctx.obsolete():
         return None
 
     ssets = successorssets(repo, ctx.node(), closest=True)
 
     # closestsuccessors returns an empty list for pruned revisions, remap it
     # into a list containing an empty list for future processing
     if ssets == []:
         ssets = [_succs()]
 
     # Try to recover pruned markers
     succsmap = repo.obsstore.successors
     fullsuccessorsets = []  # successor set + markers
     for sset in ssets:
         if sset:
             fullsuccessorsets.append(sset)
         else:
             # successorsset return an empty set() when ctx or one of its
             # successors is pruned.
             # In this case, walk the obs-markers tree again starting with ctx
             # and find the relevant pruning obs-makers, the ones without
             # successors.
             # Having these markers allow us to compute some information about
             # its fate, like who pruned this changeset and when.
 
             # XXX we do not catch all prune markers (eg rewritten then pruned)
             # (fix me later)
             foundany = False
             for mark in succsmap.get(ctx.node(), ()):
                 if not mark[1]:
                     foundany = True
                     sset = _succs()
                     sset.markers.add(mark)
                     fullsuccessorsets.append(sset)
             if not foundany:
                 fullsuccessorsets.append(_succs())
 
     values = []
     for sset in fullsuccessorsets:
         values.append({b'successors': sset, b'markers': sset.markers})
 
     return values
 
 
 def _getobsfate(successorssets):
     """Compute a changeset obsolescence fate based on its successorssets.
     Successors can be the tipmost ones or the immediate ones. This function
     return values are not meant to be shown directly to users, it is meant to
     be used by internal functions only.
     Returns one fate from the following values:
     - pruned
     - diverged
     - superseded
     - superseded_split
     """
 
     if len(successorssets) == 0:
         # The commit has been pruned
         return b'pruned'
     elif len(successorssets) > 1:
         return b'diverged'
     else:
         # No divergence, only one set of successors
         successors = successorssets[0]
 
         if len(successors) == 1:
             return b'superseded'
         else:
             return b'superseded_split'
 
 
 def obsfateverb(successorset, markers):
     """Return the verb summarizing the successorset and potentially using
     information from the markers
     """
     if not successorset:
         verb = b'pruned'
     elif len(successorset) == 1:
         verb = b'rewritten'
     else:
         verb = b'split'
     return verb
 
 
 def markersdates(markers):
     """returns the list of dates for a list of markers"""
     return [m[4] for m in markers]
 
 
 def markersusers(markers):
     """Returns a sorted list of markers users without duplicates"""
     markersmeta = [dict(m[3]) for m in markers]
     users = {
         encoding.tolocal(meta[b'user'])
         for meta in markersmeta
         if meta.get(b'user')
     }
 
     return sorted(users)
 
 
 def markersoperations(markers):
     """Returns a sorted list of markers operations without duplicates"""
     markersmeta = [dict(m[3]) for m in markers]
     operations = {
         meta.get(b'operation') for meta in markersmeta if meta.get(b'operation')
     }
 
     return sorted(operations)
 
 
 def obsfateprinter(ui, repo, successors, markers, formatctx):
     """Build a obsfate string for a single successorset using all obsfate
     related function defined in obsutil
     """
     quiet = ui.quiet
     verbose = ui.verbose
     normal = not verbose and not quiet
 
     line = []
 
     # Verb
     line.append(obsfateverb(successors, markers))
 
     # Operations
     operations = markersoperations(markers)
     if operations:
         line.append(b" using %s" % b", ".join(operations))
 
     # Successors
     if successors:
         fmtsuccessors = [formatctx(repo[succ]) for succ in successors]
         line.append(b" as %s" % b", ".join(fmtsuccessors))
 
     # Users
     users = markersusers(markers)
     # Filter out current user in not verbose mode to reduce amount of
     # information
     if not verbose:
         currentuser = ui.username(acceptempty=True)
         if len(users) == 1 and currentuser in users:
             users = None
 
     if (verbose or normal) and users:
         line.append(b" by %s" % b", ".join(users))
 
     # Date
     dates = markersdates(markers)
 
     if dates and verbose:
         min_date = min(dates)
         max_date = max(dates)
 
         if min_date == max_date:
             fmtmin_date = dateutil.datestr(min_date, b'%Y-%m-%d %H:%M %1%2')
             line.append(b" (at %s)" % fmtmin_date)
         else:
             fmtmin_date = dateutil.datestr(min_date, b'%Y-%m-%d %H:%M %1%2')
             fmtmax_date = dateutil.datestr(max_date, b'%Y-%m-%d %H:%M %1%2')
             line.append(b" (between %s and %s)" % (fmtmin_date, fmtmax_date))
 
     return b"".join(line)
 
 
 filteredmsgtable = {
     b"pruned": _(b"hidden revision '%s' is pruned"),
     b"diverged": _(b"hidden revision '%s' has diverged"),
     b"superseded": _(b"hidden revision '%s' was rewritten as: %s"),
     b"superseded_split": _(b"hidden revision '%s' was split as: %s"),
     b"superseded_split_several": _(
         b"hidden revision '%s' was split as: %s and %d more"
     ),
 }
 
 
 def _getfilteredreason(repo, changeid, ctx) -> bytes:
     """return a human-friendly string on why a obsolete changeset is hidden"""
     successors = successorssets(repo, ctx.node())
     fate = _getobsfate(successors)
 
     # Be more precise in case the revision is superseded
     if fate == b'pruned':
         return filteredmsgtable[b'pruned'] % changeid
     elif fate == b'diverged':
         return filteredmsgtable[b'diverged'] % changeid
     elif fate == b'superseded':
         single_successor = short(successors[0][0])
         return filteredmsgtable[b'superseded'] % (changeid, single_successor)
     elif fate == b'superseded_split':
         succs = []
         for node_id in successors[0]:
             succs.append(short(node_id))
 
         if len(succs) <= 2:
             fmtsuccs = b', '.join(succs)
             return filteredmsgtable[b'superseded_split'] % (changeid, fmtsuccs)
         else:
             firstsuccessors = b', '.join(succs[:2])
             remainingnumber = len(succs) - 2
 
             args = (changeid, firstsuccessors, remainingnumber)
             return filteredmsgtable[b'superseded_split_several'] % args
     else:
         raise error.ProgrammingError("unhandled fate: %r" % fate)
 
 
 def divergentsets(repo, ctx):
     """Compute sets of commits divergent with a given one"""
     cache = {}
     base = {}
     for n in allpredecessors(repo.obsstore, [ctx.node()]):
         if n == ctx.node():
             # a node can't be a base for divergence with itself
             continue
         nsuccsets = successorssets(repo, n, cache)
         for nsuccset in nsuccsets:
             if ctx.node() in nsuccset:
                 # we are only interested in *other* successor sets
                 continue
             if tuple(nsuccset) in base:
                 # we already know the latest base for this divergency
                 continue
             base[tuple(nsuccset)] = n
     return [
         {b'divergentnodes': divset, b'commonpredecessor': b}
         for divset, b in base.items()
     ]
 
 
 def whyunstable(repo, ctx):
     result = []
     if ctx.orphan():
         for parent in ctx.parents():
             kind = None
             if parent.orphan():
                 kind = b'orphan'
             elif parent.obsolete():
                 kind = b'obsolete'
             if kind is not None:
                 result.append(
                     {
                         b'instability': b'orphan',
                         b'reason': b'%s parent' % kind,
                         b'node': parent.hex(),
                     }
                 )
     if ctx.phasedivergent():
         predecessors = allpredecessors(
             repo.obsstore, [ctx.node()], ignoreflags=bumpedfix
         )
         immutable = [
             repo[p] for p in predecessors if p in repo and not repo[p].mutable()
         ]
         for predecessor in immutable:
             result.append(
                 {
                     b'instability': b'phase-divergent',
                     b'reason': b'immutable predecessor',
                     b'node': predecessor.hex(),
                 }
             )
     if ctx.contentdivergent():
         dsets = divergentsets(repo, ctx)
         for dset in dsets:
             divnodes = [repo[n] for n in dset[b'divergentnodes']]
             result.append(
                 {
                     b'instability': b'content-divergent',
                     b'divergentnodes': divnodes,
                     b'reason': b'predecessor',
                     b'node': hex(dset[b'commonpredecessor']),
                 }
             )
     return result