obsolete: rename `anysuccessors` into `allsuccessors`

The "any" prefix looks like it returned a boolean. `allsuccessors` is more
accurate.

mercurial/bookmarks.py

@@ -1,275 +1,275 b''
 # Mercurial bookmark support code
 #
 # Copyright 2008 David Soria Parra <[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 mercurial.i18n import _
 from mercurial.node import hex
 from mercurial import encoding, error, util, obsolete, phases
 import errno, os
 
 def read(repo):
     '''Parse .hg/bookmarks file and return a dictionary
 
     Bookmarks are stored as {HASH}\\s{NAME}\\n (localtags format) values
     in the .hg/bookmarks file.
     Read the file and return a (name=>nodeid) dictionary
     '''
     bookmarks = {}
     try:
         for line in repo.opener('bookmarks'):
             line = line.strip()
             if not line:
                 continue
             if ' ' not in line:
                 repo.ui.warn(_('malformed line in .hg/bookmarks: %r\n') % line)
                 continue
             sha, refspec = line.split(' ', 1)
             refspec = encoding.tolocal(refspec)
             try:
                 bookmarks[refspec] = repo.changelog.lookup(sha)
             except LookupError:
                 pass
     except IOError, inst:
         if inst.errno != errno.ENOENT:
             raise
     return bookmarks
 
 def readcurrent(repo):
     '''Get the current bookmark
 
     If we use gittishsh branches we have a current bookmark that
     we are on. This function returns the name of the bookmark. It
     is stored in .hg/bookmarks.current
     '''
     mark = None
     try:
         file = repo.opener('bookmarks.current')
     except IOError, inst:
         if inst.errno != errno.ENOENT:
             raise
         return None
     try:
         # No readline() in osutil.posixfile, reading everything is cheap
         mark = encoding.tolocal((file.readlines() or [''])[0])
         if mark == '' or mark not in repo._bookmarks:
             mark = None
     finally:
         file.close()
     return mark
 
 def write(repo):
     '''Write bookmarks
 
     Write the given bookmark => hash dictionary to the .hg/bookmarks file
     in a format equal to those of localtags.
 
     We also store a backup of the previous state in undo.bookmarks that
     can be copied back on rollback.
     '''
     refs = repo._bookmarks
 
     if repo._bookmarkcurrent not in refs:
         setcurrent(repo, None)
 
     wlock = repo.wlock()
     try:
 
         file = repo.opener('bookmarks', 'w', atomictemp=True)
         for refspec, node in refs.iteritems():
             file.write("%s %s\n" % (hex(node), encoding.fromlocal(refspec)))
         file.close()
 
         # touch 00changelog.i so hgweb reloads bookmarks (no lock needed)
         try:
             os.utime(repo.sjoin('00changelog.i'), None)
         except OSError:
             pass
 
     finally:
         wlock.release()
 
 def setcurrent(repo, mark):
     '''Set the name of the bookmark that we are currently on
 
     Set the name of the bookmark that we are on (hg update <bookmark>).
     The name is recorded in .hg/bookmarks.current
     '''
     current = repo._bookmarkcurrent
     if current == mark:
         return
 
     if mark not in repo._bookmarks:
         mark = ''
 
     wlock = repo.wlock()
     try:
         file = repo.opener('bookmarks.current', 'w', atomictemp=True)
         file.write(encoding.fromlocal(mark))
         file.close()
     finally:
         wlock.release()
     repo._bookmarkcurrent = mark
 
 def unsetcurrent(repo):
     wlock = repo.wlock()
     try:
         try:
             util.unlink(repo.join('bookmarks.current'))
             repo._bookmarkcurrent = None
         except OSError, inst:
             if inst.errno != errno.ENOENT:
                 raise
     finally:
         wlock.release()
 
 def updatecurrentbookmark(repo, oldnode, curbranch):
     try:
         return update(repo, oldnode, repo.branchtip(curbranch))
     except error.RepoLookupError:
         if curbranch == "default": # no default branch!
             return update(repo, oldnode, repo.lookup("tip"))
         else:
             raise util.Abort(_("branch %s not found") % curbranch)
 
 def update(repo, parents, node):
     marks = repo._bookmarks
     update = False
     cur = repo._bookmarkcurrent
     if not cur:
         return False
 
     toupdate = [b for b in marks if b.split('@', 1)[0] == cur.split('@', 1)[0]]
     for mark in toupdate:
         if mark and marks[mark] in parents:
             old = repo[marks[mark]]
             new = repo[node]
             if old.descendant(new) and mark == cur:
                 marks[cur] = new.node()
                 update = True
             if mark != cur:
                 del marks[mark]
     if update:
         repo._writebookmarks(marks)
     return update
 
 def listbookmarks(repo):
     # We may try to list bookmarks on a repo type that does not
     # support it (e.g., statichttprepository).
     marks = getattr(repo, '_bookmarks', {})
 
     d = {}
     for k, v in marks.iteritems():
         # don't expose local divergent bookmarks
         if '@' not in k or k.endswith('@'):
             d[k] = hex(v)
     return d
 
 def pushbookmark(repo, key, old, new):
     w = repo.wlock()
     try:
         marks = repo._bookmarks
         if hex(marks.get(key, '')) != old:
             return False
         if new == '':
             del marks[key]
         else:
             if new not in repo:
                 return False
             marks[key] = repo[new].node()
         write(repo)
         return True
     finally:
         w.release()
 
 def updatefromremote(ui, repo, remote, path):
     ui.debug("checking for updated bookmarks\n")
     rb = remote.listkeys('bookmarks')
     changed = False
     for k in rb.keys():
         if k in repo._bookmarks:
             nr, nl = rb[k], repo._bookmarks[k]
             if nr in repo:
                 cr = repo[nr]
                 cl = repo[nl]
                 if cl.rev() >= cr.rev():
                     continue
                 if validdest(repo, cl, cr):
                     repo._bookmarks[k] = cr.node()
                     changed = True
                     ui.status(_("updating bookmark %s\n") % k)
                 else:
                     if k == '@':
                         kd = ''
                     else:
                         kd = k
                     # find a unique @ suffix
                     for x in range(1, 100):
                         n = '%s@%d' % (kd, x)
                         if n not in repo._bookmarks:
                             break
                     # try to use an @pathalias suffix
                     # if an @pathalias already exists, we overwrite (update) it
                     for p, u in ui.configitems("paths"):
                         if path == u:
                             n = '%s@%s' % (kd, p)
 
                     repo._bookmarks[n] = cr.node()
                     changed = True
                     ui.warn(_("divergent bookmark %s stored as %s\n") % (k, n))
         elif rb[k] in repo:
             # add remote bookmarks for changes we already have
             repo._bookmarks[k] = repo[rb[k]].node()
             changed = True
             ui.status(_("adding remote bookmark %s\n") % k)
 
     if changed:
         write(repo)
 
 def diff(ui, dst, src):
     ui.status(_("searching for changed bookmarks\n"))
 
     smarks = src.listkeys('bookmarks')
     dmarks = dst.listkeys('bookmarks')
 
     diff = sorted(set(smarks) - set(dmarks))
     for k in diff:
         mark = ui.debugflag and smarks[k] or smarks[k][:12]
         ui.write("   %-25s %s\n" % (k, mark))
 
     if len(diff) <= 0:
         ui.status(_("no changed bookmarks found\n"))
         return 1
     return 0
 
 def validdest(repo, old, new):
     """Is the new bookmark destination a valid update from the old one"""
     if old == new:
         # Old == new -> nothing to update.
         return False
     elif not old:
         # old is nullrev, anything is valid.
         # (new != nullrev has been excluded by the previous check)
         return True
     elif repo.obsstore:
         # We only need this complicated logic if there is obsolescence
         # XXX will probably deserve an optimised revset.
 
         validdests = set([old])
         plen = -1
         # compute the whole set of successors or descendants
         while len(validdests) != plen:
             plen = len(validdests)
             succs = set(c.node() for c in validdests)
             for c in validdests:
                 if c.phase() > phases.public:
                     # obsolescence marker does not apply to public changeset
-                    succs.update(obsolete.anysuccessors(repo.obsstore,
+                    succs.update(obsolete.allsuccessors(repo.obsstore,
                                                         c.node()))
             validdests = set(repo.set('%ln::', succs))
         validdests.remove(old)
         return new in validdests
     else:
         return old.descendant(new)

mercurial/discovery.py

@@ -1,377 +1,377 b''
 # discovery.py - protocol changeset discovery functions
 #
 # Copyright 2010 Matt Mackall <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
 from node import nullid, short
 from i18n import _
 import util, setdiscovery, treediscovery, phases, obsolete, bookmarks
 
 def findcommonincoming(repo, remote, heads=None, force=False):
     """Return a tuple (common, anyincoming, heads) used to identify the common
     subset of nodes between repo and remote.
 
     "common" is a list of (at least) the heads of the common subset.
     "anyincoming" is testable as a boolean indicating if any nodes are missing
       locally. If remote does not support getbundle, this actually is a list of
       roots of the nodes that would be incoming, to be supplied to
       changegroupsubset. No code except for pull should be relying on this fact
       any longer.
     "heads" is either the supplied heads, or else the remote's heads.
 
     If you pass heads and they are all known locally, the response lists just
     these heads in "common" and in "heads".
 
     Please use findcommonoutgoing to compute the set of outgoing nodes to give
     extensions a good hook into outgoing.
     """
 
     if not remote.capable('getbundle'):
         return treediscovery.findcommonincoming(repo, remote, heads, force)
 
     if heads:
         allknown = True
         nm = repo.changelog.nodemap
         for h in heads:
             if nm.get(h) is None:
                 allknown = False
                 break
         if allknown:
             return (heads, False, heads)
 
     res = setdiscovery.findcommonheads(repo.ui, repo, remote,
                                        abortwhenunrelated=not force)
     common, anyinc, srvheads = res
     return (list(common), anyinc, heads or list(srvheads))
 
 class outgoing(object):
     '''Represents the set of nodes present in a local repo but not in a
     (possibly) remote one.
 
     Members:
 
       missing is a list of all nodes present in local but not in remote.
       common is a list of all nodes shared between the two repos.
       excluded is the list of missing changeset that shouldn't be sent remotely.
       missingheads is the list of heads of missing.
       commonheads is the list of heads of common.
 
     The sets are computed on demand from the heads, unless provided upfront
     by discovery.'''
 
     def __init__(self, revlog, commonheads, missingheads):
         self.commonheads = commonheads
         self.missingheads = missingheads
         self._revlog = revlog
         self._common = None
         self._missing = None
         self.excluded = []
 
     def _computecommonmissing(self):
         sets = self._revlog.findcommonmissing(self.commonheads,
                                               self.missingheads)
         self._common, self._missing = sets
 
     @util.propertycache
     def common(self):
         if self._common is None:
             self._computecommonmissing()
         return self._common
 
     @util.propertycache
     def missing(self):
         if self._missing is None:
             self._computecommonmissing()
         return self._missing
 
 def findcommonoutgoing(repo, other, onlyheads=None, force=False,
                        commoninc=None, portable=False):
     '''Return an outgoing instance to identify the nodes present in repo but
     not in other.
 
     If onlyheads is given, only nodes ancestral to nodes in onlyheads
     (inclusive) are included. If you already know the local repo's heads,
     passing them in onlyheads is faster than letting them be recomputed here.
 
     If commoninc is given, it must be the result of a prior call to
     findcommonincoming(repo, other, force) to avoid recomputing it here.
 
     If portable is given, compute more conservative common and missingheads,
     to make bundles created from the instance more portable.'''
     # declare an empty outgoing object to be filled later
     og = outgoing(repo.changelog, None, None)
 
     # get common set if not provided
     if commoninc is None:
         commoninc = findcommonincoming(repo, other, force=force)
     og.commonheads, _any, _hds = commoninc
 
     # compute outgoing
     mayexclude = (repo._phasecache.phaseroots[phases.secret] or repo.obsstore)
     if not mayexclude:
         og.missingheads = onlyheads or repo.heads()
     elif onlyheads is None:
         # use visible heads as it should be cached
         og.missingheads = visibleheads(repo)
         og.excluded = [ctx.node() for ctx in repo.set('secret() or extinct()')]
     else:
         # compute common, missing and exclude secret stuff
         sets = repo.changelog.findcommonmissing(og.commonheads, onlyheads)
         og._common, allmissing = sets
         og._missing = missing = []
         og.excluded = excluded = []
         for node in allmissing:
             ctx = repo[node]
             if ctx.phase() >= phases.secret or ctx.extinct():
                 excluded.append(node)
             else:
                 missing.append(node)
         if len(missing) == len(allmissing):
             missingheads = onlyheads
         else: # update missing heads
             missingheads = phases.newheads(repo, onlyheads, excluded)
         og.missingheads = missingheads
     if portable:
         # recompute common and missingheads as if -r<rev> had been given for
         # each head of missing, and --base <rev> for each head of the proper
         # ancestors of missing
         og._computecommonmissing()
         cl = repo.changelog
         missingrevs = set(cl.rev(n) for n in og._missing)
         og._common = set(cl.ancestors(missingrevs)) - missingrevs
         commonheads = set(og.commonheads)
         og.missingheads = [h for h in og.missingheads if h not in commonheads]
 
     return og
 
 def _headssummary(repo, remote, outgoing):
     """compute a summary of branch and heads status before and after push
 
     return {'branch': ([remoteheads], [newheads], [unsyncedheads])} mapping
 
     - branch: the branch name
     - remoteheads: the list of remote heads known locally
                    None is the branch is new
     - newheads: the new remote heads (known locally) with outgoing pushed
     - unsyncedheads: the list of remote heads unknown locally.
     """
     cl = repo.changelog
     headssum = {}
     # A. Create set of branches involved in the push.
     branches = set(repo[n].branch() for n in outgoing.missing)
     remotemap = remote.branchmap()
     newbranches = branches - set(remotemap)
     branches.difference_update(newbranches)
 
     # A. register remote heads
     remotebranches = set()
     for branch, heads in remote.branchmap().iteritems():
         remotebranches.add(branch)
         known = []
         unsynced = []
         for h in heads:
             if h in cl.nodemap:
                 known.append(h)
             else:
                 unsynced.append(h)
         headssum[branch] = (known, list(known), unsynced)
     # B. add new branch data
     missingctx = list(repo[n] for n in outgoing.missing)
     touchedbranches = set()
     for ctx in missingctx:
         branch = ctx.branch()
         touchedbranches.add(branch)
         if branch not in headssum:
             headssum[branch] = (None, [], [])
 
     # C drop data about untouched branches:
     for branch in remotebranches - touchedbranches:
         del headssum[branch]
 
     # D. Update newmap with outgoing changes.
     # This will possibly add new heads and remove existing ones.
     newmap = dict((branch, heads[1]) for branch, heads in headssum.iteritems()
                   if heads[0] is not None)
     repo._updatebranchcache(newmap, missingctx)
     for branch, newheads in newmap.iteritems():
         headssum[branch][1][:] = newheads
     return headssum
 
 def _oldheadssummary(repo, remoteheads, outgoing, inc=False):
     """Compute branchmapsummary for repo without branchmap support"""
 
     cl = repo.changelog
     # 1-4b. old servers: Check for new topological heads.
     # Construct {old,new}map with branch = None (topological branch).
     # (code based on _updatebranchcache)
     oldheads = set(h for h in remoteheads if h in cl.nodemap)
     # all nodes in outgoing.missing are children of either:
     # - an element of oldheads
     # - another element of outgoing.missing
     # - nullrev
     # This explains why the new head are very simple to compute.
     r = repo.set('heads(%ln + %ln)', oldheads, outgoing.missing)
     newheads = list(c.node() for c in r)
     unsynced = inc and set([None]) or set()
     return {None: (oldheads, newheads, unsynced)}
 
 def checkheads(repo, remote, outgoing, remoteheads, newbranch=False, inc=False):
     """Check that a push won't add any outgoing head
 
     raise Abort error and display ui message as needed.
     """
     # Check for each named branch if we're creating new remote heads.
     # To be a remote head after push, node must be either:
     # - unknown locally
     # - a local outgoing head descended from update
     # - a remote head that's known locally and not
     #   ancestral to an outgoing head
     if remoteheads == [nullid]:
         # remote is empty, nothing to check.
         return
 
     if remote.capable('branchmap'):
         headssum = _headssummary(repo, remote, outgoing)
     else:
         headssum = _oldheadssummary(repo, remoteheads, outgoing, inc)
     newbranches = [branch for branch, heads in headssum.iteritems()
                    if heads[0] is None]
     # 1. Check for new branches on the remote.
     if newbranches and not newbranch:  # new branch requires --new-branch
         branchnames = ', '.join(sorted(newbranches))
         raise util.Abort(_("push creates new remote branches: %s!")
                            % branchnames,
                          hint=_("use 'hg push --new-branch' to create"
                                 " new remote branches"))
 
     # 2 compute newly pushed bookmarks. We
     # we don't warned about bookmarked heads.
     localbookmarks = repo._bookmarks
     remotebookmarks = remote.listkeys('bookmarks')
     bookmarkedheads = set()
     for bm in localbookmarks:
         rnode = remotebookmarks.get(bm)
         if rnode and rnode in repo:
             lctx, rctx = repo[bm], repo[rnode]
             if bookmarks.validdest(repo, rctx, lctx):
                 bookmarkedheads.add(lctx.node())
 
     # 3. Check for new heads.
     # If there are more heads after the push than before, a suitable
     # error message, depending on unsynced status, is displayed.
     error = None
     unsynced = False
     allmissing = set(outgoing.missing)
     allfuturecommon = set(c.node() for c in repo.set('%ld', outgoing.common))
     allfuturecommon.update(allmissing)
     for branch, heads in headssum.iteritems():
         if heads[0] is None:
             # Maybe we should abort if we push more that one head
             # for new branches ?
             continue
         candidate_newhs = set(heads[1])
         # add unsynced data
         oldhs = set(heads[0])
         oldhs.update(heads[2])
         candidate_newhs.update(heads[2])
         dhs = None
         discardedheads = set()
         if repo.obsstore:
             # remove future heads which are actually obsolete by another
             # pushed element:
             #
             # XXX as above, There are several cases this case does not handle
             # XXX properly
             #
             # (1) if <nh> is public, it won't be affected by obsolete marker
             #     and a new is created
             #
             # (2) if the new heads have ancestors which are not obsolete and
             #     not ancestors of any other heads we will have a new head too.
             #
             # This two case will be easy to handle for know changeset but much
             # more tricky for unsynced changes.
             newhs = set()
             for nh in candidate_newhs:
                 if nh in repo and repo[nh].phase() <= phases.public:
                     newhs.add(nh)
                 else:
-                    for suc in obsolete.anysuccessors(repo.obsstore, nh):
+                    for suc in obsolete.allsuccessors(repo.obsstore, nh):
                         if suc != nh and suc in allfuturecommon:
                             discardedheads.add(nh)
                             break
                     else:
                         newhs.add(nh)
         else:
             newhs = candidate_newhs
         if [h for h in heads[2] if h not in discardedheads]:
             unsynced = True
         if len(newhs) > len(oldhs):
             # strip updates to existing remote heads from the new heads list
             dhs = list(newhs - bookmarkedheads - oldhs)
         if dhs:
             if error is None:
                 if branch not in ('default', None):
                     error = _("push creates new remote head %s "
                               "on branch '%s'!") % (short(dhs[0]), branch)
                 else:
                     error = _("push creates new remote head %s!"
                               ) % short(dhs[0])
                 if heads[2]: # unsynced
                     hint = _("you should pull and merge or "
                              "use push -f to force")
                 else:
                     hint = _("did you forget to merge? "
                              "use push -f to force")
             if branch is not None:
                 repo.ui.note(_("new remote heads on branch '%s'\n") % branch)
             for h in dhs:
                 repo.ui.note(_("new remote head %s\n") % short(h))
     if error:
         raise util.Abort(error, hint=hint)
 
     # 6. Check for unsynced changes on involved branches.
     if unsynced:
         repo.ui.warn(_("note: unsynced remote changes!\n"))
 
 def visibleheads(repo):
     """return the set of visible head of this repo"""
     # XXX we want a cache on this
     sroots = repo._phasecache.phaseroots[phases.secret]
     if sroots or repo.obsstore:
         # XXX very slow revset. storing heads or secret "boundary"
         # would help.
         revset = repo.set('heads(not (%ln:: + extinct()))', sroots)
 
         vheads = [ctx.node() for ctx in revset]
         if not vheads:
             vheads.append(nullid)
     else:
         vheads = repo.heads()
     return vheads
 
 
 def visiblebranchmap(repo):
     """return a branchmap for the visible set"""
     # XXX Recomputing this data on the fly is very slow.  We should build a
     # XXX cached version while computing the standard branchmap version.
     sroots = repo._phasecache.phaseroots[phases.secret]
     if sroots or repo.obsstore:
         vbranchmap = {}
         for branch, nodes in  repo.branchmap().iteritems():
             # search for secret heads.
             for n in nodes:
                 if repo[n].phase() >= phases.secret:
                     nodes = None
                     break
             # if secret heads were found we must compute them again
             if nodes is None:
                 s = repo.set('heads(branch(%s) - secret() - extinct())',
                              branch)
                 nodes = [c.node() for c in s]
             vbranchmap[branch] = nodes
     else:
         vbranchmap = repo.branchmap()
     return vbranchmap

mercurial/obsolete.py

@@ -1,467 +1,467 b''
 # 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 markers 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 rewriting operations, and help
 building new tools to reconciliate conflicting rewriting actions. To
 facilitate conflicts resolution, markers include various annotations
 besides old and news changeset identifiers, such as creation date or
 author name.
 
 The old obsoleted changeset is called "precursor" and possible replacements are
 called "successors".  Markers that used changeset X as a precursors 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 "precursor markers of
 Y" because they hold information about the precursors of Y.
 
 Examples:
 
 - When changeset A is replacement by a 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 in create:
 
     (A, ())
 
 - When changeset A is split into B and C, a single marker are used:
 
     (A, (C, C))
 
   We use a single marker to distinct the "split" case from the "divergence"
   case. If two independants operation rewrite the same changeset A in to A' and
   A'' when 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. Each marker is made of:
 
 - 1 unsigned byte: number of new changesets "R", could be zero.
 
 - 1 unsigned 32-bits integer: metadata size "M" in bytes.
 
 - 1 byte: a bit field. It is reserved for flags used in obsolete
   markers common 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 color ':', without
   additional encoding. Keys cannot contain '\0' or ':' and values
   cannot contain '\0'.
 """
 import struct
 import util, base85, node
 from i18n import _
 
 _pack = struct.pack
 _unpack = struct.unpack
 
 _SEEK_END = 2 # os.SEEK_END was introduced in Python 2.5
 
 # the obsolete feature is not mature enough to be enabled by default.
 # you have to rely on third party extension extension to enable this.
 _enabled = False
 
 # data used for parsing and writing
 _fmversion = 0
 _fmfixed   = '>BIB20s'
 _fmnode = '20s'
 _fmfsize = struct.calcsize(_fmfixed)
 _fnodesize = struct.calcsize(_fmnode)
 
 def _readmarkers(data):
     """Read and enumerate markers from raw data"""
     off = 0
     diskversion = _unpack('>B', data[off:off + 1])[0]
     off += 1
     if diskversion != _fmversion:
         raise util.Abort(_('parsing obsolete marker: unknown version %r')
                          % diskversion)
 
     # Loop on markers
     l = len(data)
     while off + _fmfsize <= l:
         # read fixed part
         cur = data[off:off + _fmfsize]
         off += _fmfsize
         nbsuc, mdsize, flags, pre = _unpack(_fmfixed, cur)
         # read replacement
         sucs = ()
         if nbsuc:
             s = (_fnodesize * nbsuc)
             cur = data[off:off + s]
             sucs = _unpack(_fmnode * nbsuc, cur)
             off += s
         # read metadata
         # (metadata will be decoded on demand)
         metadata = data[off:off + mdsize]
         if len(metadata) != mdsize:
             raise util.Abort(_('parsing obsolete marker: metadata is too '
                                'short, %d bytes expected, got %d')
                              % (mdsize, len(metadata)))
         off += mdsize
         yield (pre, sucs, flags, metadata)
 
 def encodemeta(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.iteritems():
         if ':' in key or '\0' in key:
             raise ValueError("':' and '\0' are forbidden in metadata key'")
         if '\0' in value:
             raise ValueError("':' are forbidden in metadata value'")
     return '\0'.join(['%s:%s' % (k, meta[k]) for k in sorted(meta)])
 
 def decodemeta(data):
     """Return string to string dictionary from encoded version."""
     d = {}
     for l in data.split('\0'):
         if l:
             key, value = l.split(':')
             d[key] = value
     return d
 
 class marker(object):
     """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 precnode(self):
         """Precursor changeset node identifier"""
         return self._data[0]
 
     def succnodes(self):
         """List of successor changesets node identifiers"""
         return self._data[1]
 
     def metadata(self):
         """Decoded metadata dictionary"""
         if self._decodedmeta is None:
             self._decodedmeta = decodemeta(self._data[3])
         return self._decodedmeta
 
     def date(self):
         """Creation date as (unixtime, offset)"""
         parts = self.metadata()['date'].split(' ')
         return (float(parts[0]), int(parts[1]))
 
 class obsstore(object):
     """Store obsolete markers
 
     Markers can be accessed with two mappings:
     - precursors[x] -> set(markers on precursors edges of x)
     - successors[x] -> set(markers on successors edges of x)
     """
 
     def __init__(self, sopener):
         # caches for various obsolescence related cache
         self.caches = {}
         self._all = []
         # new markers to serialize
         self.precursors = {}
         self.successors = {}
         self.sopener = sopener
         data = sopener.tryread('obsstore')
         if data:
             self._load(_readmarkers(data))
 
     def __iter__(self):
         return iter(self._all)
 
     def __nonzero__(self):
         return bool(self._all)
 
     def create(self, transaction, prec, succs=(), flag=0, metadata=None):
         """obsolete: add a new obsolete marker
 
         * ensuring it is hashable
         * check mandatory metadata
         * encode metadata
         """
         if metadata is None:
             metadata = {}
         if len(prec) != 20:
             raise ValueError(prec)
         for succ in succs:
             if len(succ) != 20:
                 raise ValueError(succ)
         marker = (str(prec), tuple(succs), int(flag), encodemeta(metadata))
         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 not _enabled:
             raise util.Abort('obsolete feature is not enabled on this repo')
         new = [m for m in markers if m not in self._all]
         if new:
             f = self.sopener('obsstore', 'ab')
             try:
                 # Whether the file's current position is at the begin or at
                 # the end after opening a file for appending is implementation
                 # defined. So we must seek to the end before calling tell(),
                 # or we may get a zero offset for non-zero sized files on
                 # some platforms (issue3543).
                 f.seek(0, _SEEK_END)
                 offset = f.tell()
                 transaction.add('obsstore', offset)
                 # offset == 0: new file - add the version header
                 for bytes in _encodemarkers(new, offset == 0):
                     f.write(bytes)
             finally:
                 # XXX: f.close() == filecache invalidation == obsstore rebuilt.
                 # call 'filecacheentry.refresh()'  here
                 f.close()
             self._load(new)
             # new marker *may* have changed several set. invalidate the cache.
             self.caches.clear()
         return len(new)
 
     def mergemarkers(self, transaction, data):
         markers = _readmarkers(data)
         self.add(transaction, markers)
 
     def _load(self, markers):
         for mark in markers:
             self._all.append(mark)
             pre, sucs = mark[:2]
             self.successors.setdefault(pre, set()).add(mark)
             for suc in sucs:
                 self.precursors.setdefault(suc, set()).add(mark)
         if node.nullid in self.precursors:
             raise util.Abort(_('bad obsolescence marker detected: '
                                'invalid successors nullid'))
 
 def _encodemarkers(markers, addheader=False):
     # Kept separate from flushmarkers(), it will be reused for
     # markers exchange.
     if addheader:
         yield _pack('>B', _fmversion)
     for marker in markers:
         yield _encodeonemarker(marker)
 
 
 def _encodeonemarker(marker):
     pre, sucs, flags, metadata = marker
     nbsuc = len(sucs)
     format = _fmfixed + (_fmnode * nbsuc)
     data = [nbsuc, len(metadata), flags, pre]
     data.extend(sucs)
     return _pack(format, *data) + metadata
 
 # 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 listmarkers(repo):
     """List markers over pushkey"""
     if not repo.obsstore:
         return {}
     keys = {}
     parts = []
     currentlen = _maxpayload * 2  # ensure we create a new part
     for marker in  repo.obsstore:
         nextdata = _encodeonemarker(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 = ''.join([_pack('>B', _fmversion)] + part)
         keys['dump%i' % idx] = base85.b85encode(data)
     return keys
 
 def pushmarker(repo, key, old, new):
     """Push markers over pushkey"""
     if not key.startswith('dump'):
         repo.ui.warn(_('unknown key: %r') % key)
         return 0
     if old:
         repo.ui.warn(_('unexpected old value') % key)
         return 0
     data = base85.b85decode(new)
     lock = repo.lock()
     try:
         tr = repo.transaction('pushkey: obsolete markers')
         try:
             repo.obsstore.mergemarkers(tr, data)
             tr.close()
             return 1
         finally:
             tr.release()
     finally:
         lock.release()
 
 def allmarkers(repo):
     """all obsolete markers known in a repository"""
     for markerdata in repo.obsstore:
         yield marker(repo, markerdata)
 
 def precursormarkers(ctx):
     """obsolete marker marking this changeset as a successors"""
     for data in ctx._repo.obsstore.precursors.get(ctx.node(), ()):
         yield marker(ctx._repo, data)
 
 def successormarkers(ctx):
     """obsolete marker making this changeset obsolete"""
     for data in ctx._repo.obsstore.successors.get(ctx.node(), ()):
         yield marker(ctx._repo, data)
 
-def anysuccessors(obsstore, node):
+def allsuccessors(obsstore, node):
     """Yield every successor of <node>
 
     This is a linear yield unsuited to detecting split changesets."""
     remaining = set([node])
     seen = set(remaining)
     while remaining:
         current = remaining.pop()
         yield current
         for mark in obsstore.successors.get(current, ()):
             for suc in mark[1]:
                 if suc not in seen:
                     seen.add(suc)
                     remaining.add(suc)
 
 # mapping of 'set-name' -> <function to computer this set>
 cachefuncs = {}
 def cachefor(name):
     """Decorator to register a function as computing the cache for a set"""
     def decorator(func):
         assert name not in cachefuncs
         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"""
     if not repo.obsstore:
         return ()
     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 'obsstore' in repo._filecache:
         repo.obsstore.caches.clear()
 
 @cachefor('obsolete')
 def _computeobsoleteset(repo):
     """the set of obsolete revisions"""
     obs = set()
     nm = repo.changelog.nodemap
     for node in repo.obsstore.successors:
         rev = nm.get(node)
         if rev is not None:
             obs.add(rev)
     return set(repo.revs('%ld - public()', obs))
 
 @cachefor('unstable')
 def _computeunstableset(repo):
     """the set of non obsolete revisions with obsolete parents"""
     return set(repo.revs('(obsolete()::) - obsolete()'))
 
 @cachefor('suspended')
 def _computesuspendedset(repo):
     """the set of obsolete parents with non obsolete descendants"""
     return set(repo.revs('obsolete() and obsolete()::unstable()'))
 
 @cachefor('extinct')
 def _computeextinctset(repo):
     """the set of obsolete parents without non obsolete descendants"""
     return set(repo.revs('obsolete() - obsolete()::unstable()'))
 
 def createmarkers(repo, relations, flag=0, metadata=None):
     """Add obsolete markers between changesets in a repo
 
     <relations> must be an iterable of (<old>, (<new>, ...)) tuple.
     `old` and `news` are changectx.
 
     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 'date' not in metadata:
         metadata['date'] = '%i %i' % util.makedate()
     if 'user' not in metadata:
         metadata['user'] = repo.ui.username()
     tr = repo.transaction('add-obsolescence-marker')
     try:
         for prec, sucs in relations:
             if not prec.mutable():
                 raise util.Abort("cannot obsolete immutable changeset: %s"
                                  % prec)
             nprec = prec.node()
             nsucs = tuple(s.node() for s in sucs)
             if nprec in nsucs:
                 raise util.Abort("changeset %s cannot obsolete itself" % prec)
             repo.obsstore.create(tr, nprec, nsucs, flag, metadata)
         tr.close()
     finally:
         tr.release()