repoview: remove unreachable code

Found using Cython.

hgext/transplant.py

@@ -1,678 +1,678
 # Patch transplanting extension for Mercurial
 #
 # Copyright 2006, 2007 Brendan Cully <[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.
 
 '''command to transplant changesets from another branch
 
 This extension allows you to transplant patches from another branch.
 
 Transplanted patches are recorded in .hg/transplant/transplants, as a
 map from a changeset hash to its hash in the source repository.
 '''
 
 from mercurial.i18n import _
 import os, tempfile
 from mercurial.node import short
 from mercurial import bundlerepo, hg, merge, match
 from mercurial import patch, revlog, scmutil, util, error, cmdutil
 from mercurial import revset, templatekw
 
 class TransplantError(error.Abort):
     pass
 
 cmdtable = {}
 command = cmdutil.command(cmdtable)
 testedwith = 'internal'
 
 class transplantentry(object):
     def __init__(self, lnode, rnode):
         self.lnode = lnode
         self.rnode = rnode
 
 class transplants(object):
     def __init__(self, path=None, transplantfile=None, opener=None):
         self.path = path
         self.transplantfile = transplantfile
         self.opener = opener
 
         if not opener:
             self.opener = scmutil.opener(self.path)
         self.transplants = {}
         self.dirty = False
         self.read()
 
     def read(self):
         abspath = os.path.join(self.path, self.transplantfile)
         if self.transplantfile and os.path.exists(abspath):
             for line in self.opener.read(self.transplantfile).splitlines():
                 lnode, rnode = map(revlog.bin, line.split(':'))
                 list = self.transplants.setdefault(rnode, [])
                 list.append(transplantentry(lnode, rnode))
 
     def write(self):
         if self.dirty and self.transplantfile:
             if not os.path.isdir(self.path):
                 os.mkdir(self.path)
             fp = self.opener(self.transplantfile, 'w')
             for list in self.transplants.itervalues():
                 for t in list:
                     l, r = map(revlog.hex, (t.lnode, t.rnode))
                     fp.write(l + ':' + r + '\n')
             fp.close()
         self.dirty = False
 
     def get(self, rnode):
         return self.transplants.get(rnode) or []
 
     def set(self, lnode, rnode):
         list = self.transplants.setdefault(rnode, [])
         list.append(transplantentry(lnode, rnode))
         self.dirty = True
 
     def remove(self, transplant):
         list = self.transplants.get(transplant.rnode)
         if list:
             del list[list.index(transplant)]
             self.dirty = True
 
 class transplanter(object):
     def __init__(self, ui, repo):
         self.ui = ui
         self.path = repo.join('transplant')
         self.opener = scmutil.opener(self.path)
         self.transplants = transplants(self.path, 'transplants',
                                        opener=self.opener)
         self.editor = None
 
     def applied(self, repo, node, parent):
         '''returns True if a node is already an ancestor of parent
         or is parent or has already been transplanted'''
         if hasnode(repo, parent):
             parentrev = repo.changelog.rev(parent)
         if hasnode(repo, node):
             rev = repo.changelog.rev(node)
             reachable = repo.changelog.ancestors([parentrev], rev,
                                                  inclusive=True)
             if rev in reachable:
                 return True
         for t in self.transplants.get(node):
             # it might have been stripped
             if not hasnode(repo, t.lnode):
                 self.transplants.remove(t)
                 return False
             lnoderev = repo.changelog.rev(t.lnode)
             if lnoderev in repo.changelog.ancestors([parentrev], lnoderev,
                                                     inclusive=True):
                 return True
         return False
 
     def apply(self, repo, source, revmap, merges, opts={}):
         '''apply the revisions in revmap one by one in revision order'''
         revs = sorted(revmap)
         p1, p2 = repo.dirstate.parents()
         pulls = []
         diffopts = patch.diffopts(self.ui, opts)
         diffopts.git = True
 
         lock = wlock = tr = None
         try:
             wlock = repo.wlock()
             lock = repo.lock()
             tr = repo.transaction('transplant')
             for rev in revs:
                 node = revmap[rev]
                 revstr = '%s:%s' % (rev, short(node))
 
                 if self.applied(repo, node, p1):
                     self.ui.warn(_('skipping already applied revision %s\n') %
                                  revstr)
                     continue
 
                 parents = source.changelog.parents(node)
                 if not (opts.get('filter') or opts.get('log')):
                     # If the changeset parent is the same as the
                     # wdir's parent, just pull it.
                     if parents[0] == p1:
                         pulls.append(node)
                         p1 = node
                         continue
                     if pulls:
                         if source != repo:
                             repo.pull(source.peer(), heads=pulls)
                         merge.update(repo, pulls[-1], False, False, None)
                         p1, p2 = repo.dirstate.parents()
                         pulls = []
 
                 domerge = False
                 if node in merges:
                     # pulling all the merge revs at once would mean we
                     # couldn't transplant after the latest even if
                     # transplants before them fail.
                     domerge = True
                     if not hasnode(repo, node):
                         repo.pull(source, heads=[node])
 
                 skipmerge = False
                 if parents[1] != revlog.nullid:
                     if not opts.get('parent'):
                         self.ui.note(_('skipping merge changeset %s:%s\n')
                                      % (rev, short(node)))
                         skipmerge = True
                     else:
                         parent = source.lookup(opts['parent'])
                         if parent not in parents:
                             raise util.Abort(_('%s is not a parent of %s') %
                                              (short(parent), short(node)))
                 else:
                     parent = parents[0]
 
                 if skipmerge:
                     patchfile = None
                 else:
                     fd, patchfile = tempfile.mkstemp(prefix='hg-transplant-')
                     fp = os.fdopen(fd, 'w')
                     gen = patch.diff(source, parent, node, opts=diffopts)
                     for chunk in gen:
                         fp.write(chunk)
                     fp.close()
 
                 del revmap[rev]
                 if patchfile or domerge:
                     try:
                         try:
                             n = self.applyone(repo, node,
                                               source.changelog.read(node),
                                               patchfile, merge=domerge,
                                               log=opts.get('log'),
                                               filter=opts.get('filter'))
                         except TransplantError:
                             # Do not rollback, it is up to the user to
                             # fix the merge or cancel everything
                             tr.close()
                             raise
                         if n and domerge:
                             self.ui.status(_('%s merged at %s\n') % (revstr,
                                       short(n)))
                         elif n:
                             self.ui.status(_('%s transplanted to %s\n')
                                            % (short(node),
                                               short(n)))
                     finally:
                         if patchfile:
                             os.unlink(patchfile)
             tr.close()
             if pulls:
                 repo.pull(source.peer(), heads=pulls)
                 merge.update(repo, pulls[-1], False, False, None)
         finally:
             self.saveseries(revmap, merges)
             self.transplants.write()
             if tr:
                 tr.release()
             lock.release()
             wlock.release()
 
     def filter(self, filter, node, changelog, patchfile):
         '''arbitrarily rewrite changeset before applying it'''
 
         self.ui.status(_('filtering %s\n') % patchfile)
         user, date, msg = (changelog[1], changelog[2], changelog[4])
         fd, headerfile = tempfile.mkstemp(prefix='hg-transplant-')
         fp = os.fdopen(fd, 'w')
         fp.write("# HG changeset patch\n")
         fp.write("# User %s\n" % user)
         fp.write("# Date %d %d\n" % date)
         fp.write(msg + '\n')
         fp.close()
 
         try:
             util.system('%s %s %s' % (filter, util.shellquote(headerfile),
                                    util.shellquote(patchfile)),
                         environ={'HGUSER': changelog[1],
                                  'HGREVISION': revlog.hex(node),
                                  },
                         onerr=util.Abort, errprefix=_('filter failed'),
                         out=self.ui.fout)
             user, date, msg = self.parselog(file(headerfile))[1:4]
         finally:
             os.unlink(headerfile)
 
         return (user, date, msg)
 
     def applyone(self, repo, node, cl, patchfile, merge=False, log=False,
                  filter=None):
         '''apply the patch in patchfile to the repository as a transplant'''
         (manifest, user, (time, timezone), files, message) = cl[:5]
         date = "%d %d" % (time, timezone)
         extra = {'transplant_source': node}
         if filter:
             (user, date, message) = self.filter(filter, node, cl, patchfile)
 
         if log:
             # we don't translate messages inserted into commits
             message += '\n(transplanted from %s)' % revlog.hex(node)
 
         self.ui.status(_('applying %s\n') % short(node))
         self.ui.note('%s %s\n%s\n' % (user, date, message))
 
         if not patchfile and not merge:
             raise util.Abort(_('can only omit patchfile if merging'))
         if patchfile:
             try:
                 files = set()
                 patch.patch(self.ui, repo, patchfile, files=files, eolmode=None)
                 files = list(files)
             except Exception, inst:
                 seriespath = os.path.join(self.path, 'series')
                 if os.path.exists(seriespath):
                     os.unlink(seriespath)
                 p1 = repo.dirstate.p1()
                 p2 = node
                 self.log(user, date, message, p1, p2, merge=merge)
                 self.ui.write(str(inst) + '\n')
                 raise TransplantError(_('fix up the merge and run '
                                         'hg transplant --continue'))
         else:
             files = None
         if merge:
             p1, p2 = repo.dirstate.parents()
             repo.setparents(p1, node)
             m = match.always(repo.root, '')
         else:
             m = match.exact(repo.root, '', files)
 
         n = repo.commit(message, user, date, extra=extra, match=m,
                         editor=self.editor)
         if not n:
             self.ui.warn(_('skipping emptied changeset %s\n') % short(node))
             return None
         if not merge:
             self.transplants.set(n, node)
 
         return n
 
-    def resume(self, repo, source, opts=None):
+    def resume(self, repo, source, opts):
         '''recover last transaction and apply remaining changesets'''
         if os.path.exists(os.path.join(self.path, 'journal')):
-            n, node = self.recover(repo)
+            n, node = self.recover(repo, opts)
             self.ui.status(_('%s transplanted as %s\n') % (short(node),
                                                            short(n)))
         seriespath = os.path.join(self.path, 'series')
         if not os.path.exists(seriespath):
             self.transplants.write()
             return
         nodes, merges = self.readseries()
         revmap = {}
         for n in nodes:
             revmap[source.changelog.rev(n)] = n
         os.unlink(seriespath)
 
         self.apply(repo, source, revmap, merges, opts)
 
-    def recover(self, repo):
+    def recover(self, repo, opts):
         '''commit working directory using journal metadata'''
         node, user, date, message, parents = self.readlog()
         merge = False
 
         if not user or not date or not message or not parents[0]:
             raise util.Abort(_('transplant log file is corrupt'))
 
         parent = parents[0]
         if len(parents) > 1:
             if opts.get('parent'):
                 parent = source.lookup(opts['parent'])
                 if parent not in parents:
                     raise util.Abort(_('%s is not a parent of %s') %
                                      (short(parent), short(node)))
             else:
                 merge = True
 
         extra = {'transplant_source': node}
         wlock = repo.wlock()
         try:
             p1, p2 = repo.dirstate.parents()
             if p1 != parent:
                 raise util.Abort(
                     _('working dir not at transplant parent %s') %
                                  revlog.hex(parent))
             if merge:
                 repo.setparents(p1, parents[1])
             n = repo.commit(message, user, date, extra=extra,
                             editor=self.editor)
             if not n:
                 raise util.Abort(_('commit failed'))
             if not merge:
                 self.transplants.set(n, node)
             self.unlog()
 
             return n, node
         finally:
             wlock.release()
 
     def readseries(self):
         nodes = []
         merges = []
         cur = nodes
         for line in self.opener.read('series').splitlines():
             if line.startswith('# Merges'):
                 cur = merges
                 continue
             cur.append(revlog.bin(line))
 
         return (nodes, merges)
 
     def saveseries(self, revmap, merges):
         if not revmap:
             return
 
         if not os.path.isdir(self.path):
             os.mkdir(self.path)
         series = self.opener('series', 'w')
         for rev in sorted(revmap):
             series.write(revlog.hex(revmap[rev]) + '\n')
         if merges:
             series.write('# Merges\n')
             for m in merges:
                 series.write(revlog.hex(m) + '\n')
         series.close()
 
     def parselog(self, fp):
         parents = []
         message = []
         node = revlog.nullid
         inmsg = False
         user = None
         date = None
         for line in fp.read().splitlines():
             if inmsg:
                 message.append(line)
             elif line.startswith('# User '):
                 user = line[7:]
             elif line.startswith('# Date '):
                 date = line[7:]
             elif line.startswith('# Node ID '):
                 node = revlog.bin(line[10:])
             elif line.startswith('# Parent '):
                 parents.append(revlog.bin(line[9:]))
             elif not line.startswith('# '):
                 inmsg = True
                 message.append(line)
         if None in (user, date):
             raise util.Abort(_("filter corrupted changeset (no user or date)"))
         return (node, user, date, '\n'.join(message), parents)
 
     def log(self, user, date, message, p1, p2, merge=False):
         '''journal changelog metadata for later recover'''
 
         if not os.path.isdir(self.path):
             os.mkdir(self.path)
         fp = self.opener('journal', 'w')
         fp.write('# User %s\n' % user)
         fp.write('# Date %s\n' % date)
         fp.write('# Node ID %s\n' % revlog.hex(p2))
         fp.write('# Parent ' + revlog.hex(p1) + '\n')
         if merge:
             fp.write('# Parent ' + revlog.hex(p2) + '\n')
         fp.write(message.rstrip() + '\n')
         fp.close()
 
     def readlog(self):
         return self.parselog(self.opener('journal'))
 
     def unlog(self):
         '''remove changelog journal'''
         absdst = os.path.join(self.path, 'journal')
         if os.path.exists(absdst):
             os.unlink(absdst)
 
     def transplantfilter(self, repo, source, root):
         def matchfn(node):
             if self.applied(repo, node, root):
                 return False
             if source.changelog.parents(node)[1] != revlog.nullid:
                 return False
             extra = source.changelog.read(node)[5]
             cnode = extra.get('transplant_source')
             if cnode and self.applied(repo, cnode, root):
                 return False
             return True
 
         return matchfn
 
 def hasnode(repo, node):
     try:
         return repo.changelog.rev(node) is not None
     except error.RevlogError:
         return False
 
 def browserevs(ui, repo, nodes, opts):
     '''interactively transplant changesets'''
     def browsehelp(ui):
         ui.write(_('y: transplant this changeset\n'
                    'n: skip this changeset\n'
                    'm: merge at this changeset\n'
                    'p: show patch\n'
                    'c: commit selected changesets\n'
                    'q: cancel transplant\n'
                    '?: show this help\n'))
 
     displayer = cmdutil.show_changeset(ui, repo, opts)
     transplants = []
     merges = []
     for node in nodes:
         displayer.show(repo[node])
         action = None
         while not action:
             action = ui.prompt(_('apply changeset? [ynmpcq?]:'))
             if action == '?':
                 browsehelp(ui)
                 action = None
             elif action == 'p':
                 parent = repo.changelog.parents(node)[0]
                 for chunk in patch.diff(repo, parent, node):
                     ui.write(chunk)
                 action = None
             elif action not in ('y', 'n', 'm', 'c', 'q'):
                 ui.write(_('no such option\n'))
                 action = None
         if action == 'y':
             transplants.append(node)
         elif action == 'm':
             merges.append(node)
         elif action == 'c':
             break
         elif action == 'q':
             transplants = ()
             merges = ()
             break
     displayer.close()
     return (transplants, merges)
 
 @command('transplant',
     [('s', 'source', '', _('pull patches from REPO'), _('REPO')),
     ('b', 'branch', [],
      _('pull patches from branch BRANCH'), _('BRANCH')),
     ('a', 'all', None, _('pull all changesets up to BRANCH')),
     ('p', 'prune', [], _('skip over REV'), _('REV')),
     ('m', 'merge', [], _('merge at REV'), _('REV')),
     ('', 'parent', '',
      _('parent to choose when transplanting merge'), _('REV')),
     ('e', 'edit', False, _('invoke editor on commit messages')),
     ('', 'log', None, _('append transplant info to log message')),
     ('c', 'continue', None, _('continue last transplant session '
                               'after repair')),
     ('', 'filter', '',
      _('filter changesets through command'), _('CMD'))],
     _('hg transplant [-s REPO] [-b BRANCH [-a]] [-p REV] '
       '[-m REV] [REV]...'))
 def transplant(ui, repo, *revs, **opts):
     '''transplant changesets from another branch
 
     Selected changesets will be applied on top of the current working
     directory with the log of the original changeset. The changesets
     are copied and will thus appear twice in the history. Use the
     rebase extension instead if you want to move a whole branch of
     unpublished changesets.
 
     If --log is specified, log messages will have a comment appended
     of the form::
 
       (transplanted from CHANGESETHASH)
 
     You can rewrite the changelog message with the --filter option.
     Its argument will be invoked with the current changelog message as
     $1 and the patch as $2.
 
     If --source/-s is specified, selects changesets from the named
     repository. If --branch/-b is specified, selects changesets from
     the branch holding the named revision, up to that revision. If
     --all/-a is specified, all changesets on the branch will be
     transplanted, otherwise you will be prompted to select the
     changesets you want.
 
     :hg:`transplant --branch REV --all` will transplant the
     selected branch (up to the named revision) onto your current
     working directory.
 
     You can optionally mark selected transplanted changesets as merge
     changesets. You will not be prompted to transplant any ancestors
     of a merged transplant, and you can merge descendants of them
     normally instead of transplanting them.
 
     Merge changesets may be transplanted directly by specifying the
     proper parent changeset by calling :hg:`transplant --parent`.
 
     If no merges or revisions are provided, :hg:`transplant` will
     start an interactive changeset browser.
 
     If a changeset application fails, you can fix the merge by hand
     and then resume where you left off by calling :hg:`transplant
     --continue/-c`.
     '''
     def incwalk(repo, csets, match=util.always):
         for node in csets:
             if match(node):
                 yield node
 
     def transplantwalk(repo, root, branches, match=util.always):
         if not branches:
             branches = repo.heads()
         ancestors = []
         for branch in branches:
             ancestors.append(repo.changelog.ancestor(root, branch))
         for node in repo.changelog.nodesbetween(ancestors, branches)[0]:
             if match(node):
                 yield node
 
     def checkopts(opts, revs):
         if opts.get('continue'):
             if opts.get('branch') or opts.get('all') or opts.get('merge'):
                 raise util.Abort(_('--continue is incompatible with '
                                    'branch, all or merge'))
             return
         if not (opts.get('source') or revs or
                 opts.get('merge') or opts.get('branch')):
             raise util.Abort(_('no source URL, branch tag or revision '
                                'list provided'))
         if opts.get('all'):
             if not opts.get('branch'):
                 raise util.Abort(_('--all requires a branch revision'))
             if revs:
                 raise util.Abort(_('--all is incompatible with a '
                                    'revision list'))
 
     checkopts(opts, revs)
 
     if not opts.get('log'):
         opts['log'] = ui.config('transplant', 'log')
     if not opts.get('filter'):
         opts['filter'] = ui.config('transplant', 'filter')
 
     tp = transplanter(ui, repo)
     if opts.get('edit'):
         tp.editor = cmdutil.commitforceeditor
 
     p1, p2 = repo.dirstate.parents()
     if len(repo) > 0 and p1 == revlog.nullid:
         raise util.Abort(_('no revision checked out'))
     if not opts.get('continue'):
         if p2 != revlog.nullid:
             raise util.Abort(_('outstanding uncommitted merges'))
         m, a, r, d = repo.status()[:4]
         if m or a or r or d:
             raise util.Abort(_('outstanding local changes'))
 
     sourcerepo = opts.get('source')
     if sourcerepo:
         peer = hg.peer(repo, opts, ui.expandpath(sourcerepo))
         branches = map(peer.lookup, opts.get('branch', ()))
         source, csets, cleanupfn = bundlerepo.getremotechanges(ui, repo, peer,
                                     onlyheads=branches, force=True)
     else:
         source = repo
         branches = map(source.lookup, opts.get('branch', ()))
         cleanupfn = None
 
     try:
         if opts.get('continue'):
             tp.resume(repo, source, opts)
             return
 
         tf = tp.transplantfilter(repo, source, p1)
         if opts.get('prune'):
             prune = [source.lookup(r)
                      for r in scmutil.revrange(source, opts.get('prune'))]
             matchfn = lambda x: tf(x) and x not in prune
         else:
             matchfn = tf
         merges = map(source.lookup, opts.get('merge', ()))
         revmap = {}
         if revs:
             for r in scmutil.revrange(source, revs):
                 revmap[int(r)] = source.lookup(r)
         elif opts.get('all') or not merges:
             if source != repo:
                 alltransplants = incwalk(source, csets, match=matchfn)
             else:
                 alltransplants = transplantwalk(source, p1, branches,
                                                 match=matchfn)
             if opts.get('all'):
                 revs = alltransplants
             else:
                 revs, newmerges = browserevs(ui, source, alltransplants, opts)
                 merges.extend(newmerges)
             for r in revs:
                 revmap[source.changelog.rev(r)] = r
         for r in merges:
             revmap[source.changelog.rev(r)] = r
 
         tp.apply(repo, source, revmap, merges, opts)
     finally:
         if cleanupfn:
             cleanupfn()
 
 def revsettransplanted(repo, subset, x):
     """``transplanted([set])``
     Transplanted changesets in set, or all transplanted changesets.
     """
     if x:
         s = revset.getset(repo, subset, x)
     else:
         s = subset
     return [r for r in s if repo[r].extra().get('transplant_source')]
 
 def kwtransplanted(repo, ctx, **args):
     """:transplanted: String. The node identifier of the transplanted
     changeset if any."""
     n = ctx.extra().get('transplant_source')
     return n and revlog.hex(n) or ''
 
 def extsetup(ui):
     revset.symbols['transplanted'] = revsettransplanted
     templatekw.keywords['transplanted'] = kwtransplanted
 
 # tell hggettext to extract docstrings from these functions:
 i18nfunctions = [revsettransplanted, kwtransplanted]

mercurial/repoview.py

@@ -1,219 +1,218
 # repoview.py - Filtered view of a localrepo object
 #
 # 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.
 
 import copy
 import phases
 import util
 import obsolete, revset
 
 
 def hideablerevs(repo):
     """Revisions candidates to be hidden
 
     This is a standalone function to help extensions to wrap it."""
     return obsolete.getrevs(repo, 'obsolete')
 
 def computehidden(repo):
     """compute the set of hidden revision to filter
 
     During most operation hidden should be filtered."""
     assert not repo.changelog.filteredrevs
     hideable = hideablerevs(repo)
     if hideable:
         cl = repo.changelog
         firsthideable = min(hideable)
         revs = cl.revs(start=firsthideable)
         blockers = [r for r in revset._children(repo, revs, hideable)
                       if r not in hideable]
         for par in repo[None].parents():
             blockers.append(par.rev())
         for bm in repo._bookmarks.values():
             blockers.append(repo[bm].rev())
         blocked = cl.ancestors(blockers, inclusive=True)
         return frozenset(r for r in hideable if r not in blocked)
     return frozenset()
 
 def computeunserved(repo):
     """compute the set of revision that should be filtered when used a server
 
     Secret and hidden changeset should not pretend to be here."""
     assert not repo.changelog.filteredrevs
     # fast path in simple case to avoid impact of non optimised code
     hiddens = filterrevs(repo, 'visible')
     if phases.hassecret(repo):
         cl = repo.changelog
         secret = phases.secret
         getphase = repo._phasecache.phase
         first = min(cl.rev(n) for n in repo._phasecache.phaseroots[secret])
         revs = cl.revs(start=first)
         secrets = set(r for r in revs if getphase(repo, r) >= secret)
         return frozenset(hiddens | secrets)
     else:
         return hiddens
-    return frozenset()
 
 def computemutable(repo):
     """compute the set of revision that should be filtered when used a server
 
     Secret and hidden changeset should not pretend to be here."""
     assert not repo.changelog.filteredrevs
     # fast check to avoid revset call on huge repo
     if util.any(repo._phasecache.phaseroots[1:]):
         getphase = repo._phasecache.phase
         maymutable = filterrevs(repo, 'base')
         return frozenset(r for r in maymutable if getphase(repo, r))
     return frozenset()
 
 def computeimpactable(repo):
     """Everything impactable by mutable revision
 
     The immutable filter still have some chance to get invalidated. This will
     happen when:
 
     - you garbage collect hidden changeset,
     - public phase is moved backward,
     - something is changed in the filtering (this could be fixed)
 
     This filter out any mutable changeset and any public changeset that may be
     impacted by something happening to a mutable revision.
 
     This is achieved by filtered everything with a revision number egal or
     higher than the first mutable changeset is filtered."""
     assert not repo.changelog.filteredrevs
     cl = repo.changelog
     firstmutable = len(cl)
     for roots in repo._phasecache.phaseroots[1:]:
         if roots:
             firstmutable = min(firstmutable, min(cl.rev(r) for r in roots))
     # protect from nullrev root
     firstmutable = max(0, firstmutable)
     return frozenset(xrange(firstmutable, len(cl)))
 
 # function to compute filtered set
 filtertable = {'visible': computehidden,
                'served': computeunserved,
                'immutable':  computemutable,
                'base':  computeimpactable}
 ### Nearest subset relation
 # Nearest subset of filter X is a filter Y so that:
 # * Y is included in X,
 # * X - Y is as small as possible.
 # This create and ordering used for branchmap purpose.
 # the ordering may be partial
 subsettable = {None: 'visible',
                'visible': 'served',
                'served': 'immutable',
                'immutable': 'base'}
 
 def filterrevs(repo, filtername):
     """returns set of filtered revision for this filter name"""
     if filtername not in repo.filteredrevcache:
         func = filtertable[filtername]
         repo.filteredrevcache[filtername] = func(repo.unfiltered())
     return repo.filteredrevcache[filtername]
 
 class repoview(object):
     """Provide a read/write view of a repo through a filtered changelog
 
     This object is used to access a filtered version of a repository without
     altering the original repository object itself. We can not alter the
     original object for two main reasons:
     - It prevents the use of a repo with multiple filters at the same time. In
       particular when multiple threads are involved.
     - It makes scope of the filtering harder to control.
 
     This object behaves very closely to the original repository. All attribute
     operations are done on the original repository:
     - An access to `repoview.someattr` actually returns `repo.someattr`,
     - A write to `repoview.someattr` actually sets value of `repo.someattr`,
     - A deletion of `repoview.someattr` actually drops `someattr`
       from `repo.__dict__`.
 
     The only exception is the `changelog` property. It is overridden to return
     a (surface) copy of `repo.changelog` with some revisions filtered. The
     `filtername` attribute of the view control the revisions that need to be
     filtered.  (the fact the changelog is copied is an implementation detail).
 
     Unlike attributes, this object intercepts all method calls. This means that
     all methods are run on the `repoview` object with the filtered `changelog`
     property. For this purpose the simple `repoview` class must be mixed with
     the actual class of the repository. This ensures that the resulting
     `repoview` object have the very same methods than the repo object. This
     leads to the property below.
 
         repoview.method() --> repo.__class__.method(repoview)
 
     The inheritance has to be done dynamically because `repo` can be of any
     subclasses of `localrepo`. Eg: `bundlerepo` or `statichttprepo`.
     """
 
     def __init__(self, repo, filtername):
         object.__setattr__(self, '_unfilteredrepo', repo)
         object.__setattr__(self, 'filtername', filtername)
         object.__setattr__(self, '_clcachekey', None)
         object.__setattr__(self, '_clcache', None)
 
     # not a propertycache on purpose we shall implement a proper cache later
     @property
     def changelog(self):
         """return a filtered version of the changeset
 
         this changelog must not be used for writing"""
         # some cache may be implemented later
         unfi = self._unfilteredrepo
         unfichangelog = unfi.changelog
         revs = filterrevs(unfi, self.filtername)
         cl = self._clcache
         newkey = (len(unfichangelog), unfichangelog.tip(), hash(revs))
         if cl is not None:
             # we need to check curkey too for some obscure reason.
             # MQ test show a corruption of the underlying repo (in _clcache)
             # without change in the cachekey.
             oldfilter = cl.filteredrevs
             try:
                 cl.filterrevs = ()  # disable filtering for tip
                 curkey = (len(cl), cl.tip(), hash(oldfilter))
             finally:
                 cl.filteredrevs = oldfilter
             if newkey != self._clcachekey or newkey != curkey:
                 cl = None
         # could have been made None by the previous if
         if cl is None:
             cl = copy.copy(unfichangelog)
             cl.filteredrevs = revs
             object.__setattr__(self, '_clcache', cl)
             object.__setattr__(self, '_clcachekey', newkey)
         return cl
 
     def unfiltered(self):
         """Return an unfiltered version of a repo"""
         return self._unfilteredrepo
 
     def filtered(self, name):
         """Return a filtered version of a repository"""
         if name == self.filtername:
             return self
         return self.unfiltered().filtered(name)
 
     # everything access are forwarded to the proxied repo
     def __getattr__(self, attr):
         return getattr(self._unfilteredrepo, attr)
 
     def __setattr__(self, attr, value):
         return setattr(self._unfilteredrepo, attr, value)
 
     def __delattr__(self, attr):
         return delattr(self._unfilteredrepo, attr)
 
     # The `requirements` attribute is initialized during __init__. But
     # __getattr__ won't be called as it also exists on the class. We need
     # explicit forwarding to main repo here
     @property
     def requirements(self):
         return self._unfilteredrepo.requirements