repair: use `first` instead of direct indexing

This makes it compatible with all smartset classes.

mercurial/hg.py

@@ -1,669 +1,676 b''
 # hg.py - repository classes for mercurial
 #
 # Copyright 2005-2007 Matt Mackall <[e-mail]>
 # Copyright 2006 Vadim Gelfer <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
 from i18n import _
 from lock import release
 from node import nullid
 import localrepo, bundlerepo, unionrepo, httppeer, sshpeer, statichttprepo
 import bookmarks, lock, util, extensions, error, node, scmutil, phases, url
 import cmdutil, discovery, repoview, exchange
 import merge as mergemod
 import verify as verifymod
 import errno, os, shutil
 
 def _local(path):
     path = util.expandpath(util.urllocalpath(path))
     return (os.path.isfile(path) and bundlerepo or localrepo)
 
 def addbranchrevs(lrepo, other, branches, revs):
     peer = other.peer() # a courtesy to callers using a localrepo for other
     hashbranch, branches = branches
     if not hashbranch and not branches:
-        return revs or None, revs and revs[0] or None
+        x = revs or None
+        if util.safehasattr(revs, 'first'):
+            y =  revs.first()
+        elif revs:
+            y = revs[0]
+        else:
+            y = None
+        return x, y
     revs = revs and list(revs) or []
     if not peer.capable('branchmap'):
         if branches:
             raise util.Abort(_("remote branch lookup not supported"))
         revs.append(hashbranch)
         return revs, revs[0]
     branchmap = peer.branchmap()
 
     def primary(branch):
         if branch == '.':
             if not lrepo:
                 raise util.Abort(_("dirstate branch not accessible"))
             branch = lrepo.dirstate.branch()
         if branch in branchmap:
             revs.extend(node.hex(r) for r in reversed(branchmap[branch]))
             return True
         else:
             return False
 
     for branch in branches:
         if not primary(branch):
             raise error.RepoLookupError(_("unknown branch '%s'") % branch)
     if hashbranch:
         if not primary(hashbranch):
             revs.append(hashbranch)
     return revs, revs[0]
 
 def parseurl(path, branches=None):
     '''parse url#branch, returning (url, (branch, branches))'''
 
     u = util.url(path)
     branch = None
     if u.fragment:
         branch = u.fragment
         u.fragment = None
     return str(u), (branch, branches or [])
 
 schemes = {
     'bundle': bundlerepo,
     'union': unionrepo,
     'file': _local,
     'http': httppeer,
     'https': httppeer,
     'ssh': sshpeer,
     'static-http': statichttprepo,
 }
 
 def _peerlookup(path):
     u = util.url(path)
     scheme = u.scheme or 'file'
     thing = schemes.get(scheme) or schemes['file']
     try:
         return thing(path)
     except TypeError:
         return thing
 
 def islocal(repo):
     '''return true if repo (or path pointing to repo) is local'''
     if isinstance(repo, str):
         try:
             return _peerlookup(repo).islocal(repo)
         except AttributeError:
             return False
     return repo.local()
 
 def openpath(ui, path):
     '''open path with open if local, url.open if remote'''
     pathurl = util.url(path, parsequery=False, parsefragment=False)
     if pathurl.islocal():
         return util.posixfile(pathurl.localpath(), 'rb')
     else:
         return url.open(ui, path)
 
 # a list of (ui, repo) functions called for wire peer initialization
 wirepeersetupfuncs = []
 
 def _peerorrepo(ui, path, create=False):
     """return a repository object for the specified path"""
     obj = _peerlookup(path).instance(ui, path, create)
     ui = getattr(obj, "ui", ui)
     for name, module in extensions.extensions(ui):
         hook = getattr(module, 'reposetup', None)
         if hook:
             hook(ui, obj)
     if not obj.local():
         for f in wirepeersetupfuncs:
             f(ui, obj)
     return obj
 
 def repository(ui, path='', create=False):
     """return a repository object for the specified path"""
     peer = _peerorrepo(ui, path, create)
     repo = peer.local()
     if not repo:
         raise util.Abort(_("repository '%s' is not local") %
                          (path or peer.url()))
     return repo.filtered('visible')
 
 def peer(uiorrepo, opts, path, create=False):
     '''return a repository peer for the specified path'''
     rui = remoteui(uiorrepo, opts)
     return _peerorrepo(rui, path, create).peer()
 
 def defaultdest(source):
     '''return default destination of clone if none is given
 
     >>> defaultdest('foo')
     'foo'
     >>> defaultdest('/foo/bar')
     'bar'
     >>> defaultdest('/')
     ''
     >>> defaultdest('')
     ''
     >>> defaultdest('http://example.org/')
     ''
     >>> defaultdest('http://example.org/foo/')
     'foo'
     '''
     path = util.url(source).path
     if not path:
         return ''
     return os.path.basename(os.path.normpath(path))
 
 def share(ui, source, dest=None, update=True):
     '''create a shared repository'''
 
     if not islocal(source):
         raise util.Abort(_('can only share local repositories'))
 
     if not dest:
         dest = defaultdest(source)
     else:
         dest = ui.expandpath(dest)
 
     if isinstance(source, str):
         origsource = ui.expandpath(source)
         source, branches = parseurl(origsource)
         srcrepo = repository(ui, source)
         rev, checkout = addbranchrevs(srcrepo, srcrepo, branches, None)
     else:
         srcrepo = source.local()
         origsource = source = srcrepo.url()
         checkout = None
 
     sharedpath = srcrepo.sharedpath # if our source is already sharing
 
     destwvfs = scmutil.vfs(dest, realpath=True)
     destvfs = scmutil.vfs(os.path.join(destwvfs.base, '.hg'), realpath=True)
 
     if destvfs.lexists():
         raise util.Abort(_('destination already exists'))
 
     if not destwvfs.isdir():
         destwvfs.mkdir()
     destvfs.makedir()
 
     requirements = ''
     try:
         requirements = srcrepo.opener.read('requires')
     except IOError, inst:
         if inst.errno != errno.ENOENT:
             raise
 
     requirements += 'shared\n'
     destvfs.write('requires', requirements)
     destvfs.write('sharedpath', sharedpath)
 
     r = repository(ui, destwvfs.base)
 
     default = srcrepo.ui.config('paths', 'default')
     if default:
         fp = r.opener("hgrc", "w", text=True)
         fp.write("[paths]\n")
         fp.write("default = %s\n" % default)
         fp.close()
 
     if update:
         r.ui.status(_("updating working directory\n"))
         if update is not True:
             checkout = update
         for test in (checkout, 'default', 'tip'):
             if test is None:
                 continue
             try:
                 uprev = r.lookup(test)
                 break
             except error.RepoLookupError:
                 continue
         _update(r, uprev)
 
 def copystore(ui, srcrepo, destpath):
     '''copy files from store of srcrepo in destpath
 
     returns destlock
     '''
     destlock = None
     try:
         hardlink = None
         num = 0
         srcpublishing = srcrepo.ui.configbool('phases', 'publish', True)
         srcvfs = scmutil.vfs(srcrepo.sharedpath)
         dstvfs = scmutil.vfs(destpath)
         for f in srcrepo.store.copylist():
             if srcpublishing and f.endswith('phaseroots'):
                 continue
             dstbase = os.path.dirname(f)
             if dstbase and not dstvfs.exists(dstbase):
                 dstvfs.mkdir(dstbase)
             if srcvfs.exists(f):
                 if f.endswith('data'):
                     # 'dstbase' may be empty (e.g. revlog format 0)
                     lockfile = os.path.join(dstbase, "lock")
                     # lock to avoid premature writing to the target
                     destlock = lock.lock(dstvfs, lockfile)
                 hardlink, n = util.copyfiles(srcvfs.join(f), dstvfs.join(f),
                                              hardlink)
                 num += n
         if hardlink:
             ui.debug("linked %d files\n" % num)
         else:
             ui.debug("copied %d files\n" % num)
         return destlock
     except: # re-raises
         release(destlock)
         raise
 
 def clone(ui, peeropts, source, dest=None, pull=False, rev=None,
           update=True, stream=False, branch=None):
     """Make a copy of an existing repository.
 
     Create a copy of an existing repository in a new directory.  The
     source and destination are URLs, as passed to the repository
     function.  Returns a pair of repository peers, the source and
     newly created destination.
 
     The location of the source is added to the new repository's
     .hg/hgrc file, as the default to be used for future pulls and
     pushes.
 
     If an exception is raised, the partly cloned/updated destination
     repository will be deleted.
 
     Arguments:
 
     source: repository object or URL
 
     dest: URL of destination repository to create (defaults to base
     name of source repository)
 
     pull: always pull from source repository, even in local case
 
     stream: stream raw data uncompressed from repository (fast over
     LAN, slow over WAN)
 
     rev: revision to clone up to (implies pull=True)
 
     update: update working directory after clone completes, if
     destination is local repository (True means update to default rev,
     anything else is treated as a revision)
 
     branch: branches to clone
     """
 
     if isinstance(source, str):
         origsource = ui.expandpath(source)
         source, branch = parseurl(origsource, branch)
         srcpeer = peer(ui, peeropts, source)
     else:
         srcpeer = source.peer() # in case we were called with a localrepo
         branch = (None, branch or [])
         origsource = source = srcpeer.url()
     rev, checkout = addbranchrevs(srcpeer, srcpeer, branch, rev)
 
     if dest is None:
         dest = defaultdest(source)
         if dest:
             ui.status(_("destination directory: %s\n") % dest)
     else:
         dest = ui.expandpath(dest)
 
     dest = util.urllocalpath(dest)
     source = util.urllocalpath(source)
 
     if not dest:
         raise util.Abort(_("empty destination path is not valid"))
 
     destvfs = scmutil.vfs(dest, expandpath=True)
     if destvfs.lexists():
         if not destvfs.isdir():
             raise util.Abort(_("destination '%s' already exists") % dest)
         elif destvfs.listdir():
             raise util.Abort(_("destination '%s' is not empty") % dest)
 
     srclock = destlock = cleandir = None
     srcrepo = srcpeer.local()
     try:
         abspath = origsource
         if islocal(origsource):
             abspath = os.path.abspath(util.urllocalpath(origsource))
 
         if islocal(dest):
             cleandir = dest
 
         copy = False
         if (srcrepo and srcrepo.cancopy() and islocal(dest)
             and not phases.hassecret(srcrepo)):
             copy = not pull and not rev
 
         if copy:
             try:
                 # we use a lock here because if we race with commit, we
                 # can end up with extra data in the cloned revlogs that's
                 # not pointed to by changesets, thus causing verify to
                 # fail
                 srclock = srcrepo.lock(wait=False)
             except error.LockError:
                 copy = False
 
         if copy:
             srcrepo.hook('preoutgoing', throw=True, source='clone')
             hgdir = os.path.realpath(os.path.join(dest, ".hg"))
             if not os.path.exists(dest):
                 os.mkdir(dest)
             else:
                 # only clean up directories we create ourselves
                 cleandir = hgdir
             try:
                 destpath = hgdir
                 util.makedir(destpath, notindexed=True)
             except OSError, inst:
                 if inst.errno == errno.EEXIST:
                     cleandir = None
                     raise util.Abort(_("destination '%s' already exists")
                                      % dest)
                 raise
 
             destlock = copystore(ui, srcrepo, destpath)
             # copy bookmarks over
             srcbookmarks = srcrepo.join('bookmarks')
             dstbookmarks = os.path.join(destpath, 'bookmarks')
             if os.path.exists(srcbookmarks):
                 util.copyfile(srcbookmarks, dstbookmarks)
 
             # Recomputing branch cache might be slow on big repos,
             # so just copy it
             def copybranchcache(fname):
                 srcbranchcache = srcrepo.join('cache/%s' % fname)
                 dstbranchcache = os.path.join(dstcachedir, fname)
                 if os.path.exists(srcbranchcache):
                     if not os.path.exists(dstcachedir):
                         os.mkdir(dstcachedir)
                     util.copyfile(srcbranchcache, dstbranchcache)
 
             dstcachedir = os.path.join(destpath, 'cache')
             # In local clones we're copying all nodes, not just served
             # ones. Therefore copy all branchcaches over.
             copybranchcache('branch2')
             for cachename in repoview.filtertable:
                 copybranchcache('branch2-%s' % cachename)
 
             # we need to re-init the repo after manually copying the data
             # into it
             destpeer = peer(srcrepo, peeropts, dest)
             srcrepo.hook('outgoing', source='clone',
                           node=node.hex(node.nullid))
         else:
             try:
                 destpeer = peer(srcrepo or ui, peeropts, dest, create=True)
                                 # only pass ui when no srcrepo
             except OSError, inst:
                 if inst.errno == errno.EEXIST:
                     cleandir = None
                     raise util.Abort(_("destination '%s' already exists")
                                      % dest)
                 raise
 
             revs = None
             if rev:
                 if not srcpeer.capable('lookup'):
                     raise util.Abort(_("src repository does not support "
                                        "revision lookup and so doesn't "
                                        "support clone by revision"))
                 revs = [srcpeer.lookup(r) for r in rev]
                 checkout = revs[0]
             if destpeer.local():
                 destpeer.local().clone(srcpeer, heads=revs, stream=stream)
             elif srcrepo:
                 exchange.push(srcrepo, destpeer, revs=revs,
                               bookmarks=srcrepo._bookmarks.keys())
             else:
                 raise util.Abort(_("clone from remote to remote not supported"))
 
         cleandir = None
 
         destrepo = destpeer.local()
         if destrepo:
             template = (
                 '# You may want to set your username here if it is not set\n'
                 "# globally, or this repository requires a different\n"
                 '# username from your usual configuration. If you want to\n'
                 '# set something for all of your repositories on this\n'
                 '# computer, try running the command\n'
                 "# 'hg config --edit --global'\n"
                 '# [ui]\n'
                 '# username = Jane Doe <[e-mail]>\n'
                 '[paths]\n'
                 'default = %s\n'
                 )
             fp = destrepo.opener("hgrc", "w", text=True)
             u = util.url(abspath)
             u.passwd = None
             defaulturl = str(u)
             fp.write(template % defaulturl)
             fp.close()
 
             destrepo.ui.setconfig('paths', 'default', defaulturl, 'clone')
 
             if update:
                 if update is not True:
                     checkout = srcpeer.lookup(update)
                 uprev = None
                 status = None
                 if checkout is not None:
                     try:
                         uprev = destrepo.lookup(checkout)
                     except error.RepoLookupError:
                         pass
                 if uprev is None:
                     try:
                         uprev = destrepo._bookmarks['@']
                         update = '@'
                         bn = destrepo[uprev].branch()
                         if bn == 'default':
                             status = _("updating to bookmark @\n")
                         else:
                             status = (_("updating to bookmark @ on branch %s\n")
                                        % bn)
                     except KeyError:
                         try:
                             uprev = destrepo.branchtip('default')
                         except error.RepoLookupError:
                             uprev = destrepo.lookup('tip')
                 if not status:
                     bn = destrepo[uprev].branch()
                     status = _("updating to branch %s\n") % bn
                 destrepo.ui.status(status)
                 _update(destrepo, uprev)
                 if update in destrepo._bookmarks:
                     bookmarks.setcurrent(destrepo, update)
     finally:
         release(srclock, destlock)
         if cleandir is not None:
             shutil.rmtree(cleandir, True)
         if srcpeer is not None:
             srcpeer.close()
     return srcpeer, destpeer
 
 def _showstats(repo, stats):
     repo.ui.status(_("%d files updated, %d files merged, "
                      "%d files removed, %d files unresolved\n") % stats)
 
 def updaterepo(repo, node, overwrite):
     """Update the working directory to node.
 
     When overwrite is set, changes are clobbered, merged else
 
     returns stats (see pydoc mercurial.merge.applyupdates)"""
     return mergemod.update(repo, node, False, overwrite, None,
                            labels=['working copy', 'destination'])
 
 def update(repo, node):
     """update the working directory to node, merging linear changes"""
     stats = updaterepo(repo, node, False)
     _showstats(repo, stats)
     if stats[3]:
         repo.ui.status(_("use 'hg resolve' to retry unresolved file merges\n"))
     return stats[3] > 0
 
 # naming conflict in clone()
 _update = update
 
 def clean(repo, node, show_stats=True):
     """forcibly switch the working directory to node, clobbering changes"""
     stats = updaterepo(repo, node, True)
     util.unlinkpath(repo.join('graftstate'), ignoremissing=True)
     if show_stats:
         _showstats(repo, stats)
     return stats[3] > 0
 
 def merge(repo, node, force=None, remind=True):
     """Branch merge with node, resolving changes. Return true if any
     unresolved conflicts."""
     stats = mergemod.update(repo, node, True, force, False)
     _showstats(repo, stats)
     if stats[3]:
         repo.ui.status(_("use 'hg resolve' to retry unresolved file merges "
                          "or 'hg update -C .' to abandon\n"))
     elif remind:
         repo.ui.status(_("(branch merge, don't forget to commit)\n"))
     return stats[3] > 0
 
 def _incoming(displaychlist, subreporecurse, ui, repo, source,
         opts, buffered=False):
     """
     Helper for incoming / gincoming.
     displaychlist gets called with
         (remoterepo, incomingchangesetlist, displayer) parameters,
     and is supposed to contain only code that can't be unified.
     """
     source, branches = parseurl(ui.expandpath(source), opts.get('branch'))
     other = peer(repo, opts, source)
     ui.status(_('comparing with %s\n') % util.hidepassword(source))
     revs, checkout = addbranchrevs(repo, other, branches, opts.get('rev'))
 
     if revs:
         revs = [other.lookup(rev) for rev in revs]
     other, chlist, cleanupfn = bundlerepo.getremotechanges(ui, repo, other,
                                 revs, opts["bundle"], opts["force"])
     try:
         if not chlist:
             ui.status(_("no changes found\n"))
             return subreporecurse()
 
         displayer = cmdutil.show_changeset(ui, other, opts, buffered)
         displaychlist(other, chlist, displayer)
         displayer.close()
     finally:
         cleanupfn()
     subreporecurse()
     return 0 # exit code is zero since we found incoming changes
 
 def incoming(ui, repo, source, opts):
     def subreporecurse():
         ret = 1
         if opts.get('subrepos'):
             ctx = repo[None]
             for subpath in sorted(ctx.substate):
                 sub = ctx.sub(subpath)
                 ret = min(ret, sub.incoming(ui, source, opts))
         return ret
 
     def display(other, chlist, displayer):
         limit = cmdutil.loglimit(opts)
         if opts.get('newest_first'):
             chlist.reverse()
         count = 0
         for n in chlist:
             if limit is not None and count >= limit:
                 break
             parents = [p for p in other.changelog.parents(n) if p != nullid]
             if opts.get('no_merges') and len(parents) == 2:
                 continue
             count += 1
             displayer.show(other[n])
     return _incoming(display, subreporecurse, ui, repo, source, opts)
 
 def _outgoing(ui, repo, dest, opts):
     dest = ui.expandpath(dest or 'default-push', dest or 'default')
     dest, branches = parseurl(dest, opts.get('branch'))
     ui.status(_('comparing with %s\n') % util.hidepassword(dest))
     revs, checkout = addbranchrevs(repo, repo, branches, opts.get('rev'))
     if revs:
         revs = [repo.lookup(rev) for rev in scmutil.revrange(repo, revs)]
 
     other = peer(repo, opts, dest)
     outgoing = discovery.findcommonoutgoing(repo.unfiltered(), other, revs,
                                             force=opts.get('force'))
     o = outgoing.missing
     if not o:
         scmutil.nochangesfound(repo.ui, repo, outgoing.excluded)
     return o, other
 
 def outgoing(ui, repo, dest, opts):
     def recurse():
         ret = 1
         if opts.get('subrepos'):
             ctx = repo[None]
             for subpath in sorted(ctx.substate):
                 sub = ctx.sub(subpath)
                 ret = min(ret, sub.outgoing(ui, dest, opts))
         return ret
 
     limit = cmdutil.loglimit(opts)
     o, other = _outgoing(ui, repo, dest, opts)
     if not o:
         cmdutil.outgoinghooks(ui, repo, other, opts, o)
         return recurse()
 
     if opts.get('newest_first'):
         o.reverse()
     displayer = cmdutil.show_changeset(ui, repo, opts)
     count = 0
     for n in o:
         if limit is not None and count >= limit:
             break
         parents = [p for p in repo.changelog.parents(n) if p != nullid]
         if opts.get('no_merges') and len(parents) == 2:
             continue
         count += 1
         displayer.show(repo[n])
     displayer.close()
     cmdutil.outgoinghooks(ui, repo, other, opts, o)
     recurse()
     return 0 # exit code is zero since we found outgoing changes
 
 def revert(repo, node, choose):
     """revert changes to revision in node without updating dirstate"""
     return mergemod.update(repo, node, False, True, choose)[3] > 0
 
 def verify(repo):
     """verify the consistency of a repository"""
     return verifymod.verify(repo)
 
 def remoteui(src, opts):
     'build a remote ui from ui or repo and opts'
     if util.safehasattr(src, 'baseui'): # looks like a repository
         dst = src.baseui.copy() # drop repo-specific config
         src = src.ui # copy target options from repo
     else: # assume it's a global ui object
         dst = src.copy() # keep all global options
 
     # copy ssh-specific options
     for o in 'ssh', 'remotecmd':
         v = opts.get(o) or src.config('ui', o)
         if v:
             dst.setconfig("ui", o, v, 'copied')
 
     # copy bundle-specific options
     r = src.config('bundle', 'mainreporoot')
     if r:
         dst.setconfig('bundle', 'mainreporoot', r, 'copied')
 
     # copy selected local settings to the remote ui
     for sect in ('auth', 'hostfingerprints', 'http_proxy'):
         for key, val in src.configitems(sect):
             dst.setconfig(sect, key, val, 'copied')
     v = src.config('web', 'cacerts')
     if v:
         dst.setconfig('web', 'cacerts', util.expandpath(v), 'copied')
 
     return dst

mercurial/repair.py

@@ -1,189 +1,189 b''
 # repair.py - functions for repository repair for mercurial
 #
 # Copyright 2005, 2006 Chris Mason <[e-mail]>
 # Copyright 2007 Matt Mackall
 #
 # 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 import changegroup, exchange
 from mercurial.node import short
 from mercurial.i18n import _
 import errno
 
 def _bundle(repo, bases, heads, node, suffix, compress=True):
     """create a bundle with the specified revisions as a backup"""
     cg = changegroup.changegroupsubset(repo, bases, heads, 'strip')
     backupdir = "strip-backup"
     vfs = repo.vfs
     if not vfs.isdir(backupdir):
         vfs.mkdir(backupdir)
     name = "%s/%s-%s.hg" % (backupdir, short(node), suffix)
     if compress:
         bundletype = "HG10BZ"
     else:
         bundletype = "HG10UN"
     return changegroup.writebundle(cg, name, bundletype, vfs)
 
 def _collectfiles(repo, striprev):
     """find out the filelogs affected by the strip"""
     files = set()
 
     for x in xrange(striprev, len(repo)):
         files.update(repo[x].files())
 
     return sorted(files)
 
 def _collectbrokencsets(repo, files, striprev):
     """return the changesets which will be broken by the truncation"""
     s = set()
     def collectone(revlog):
         _, brokenset = revlog.getstrippoint(striprev)
         s.update([revlog.linkrev(r) for r in brokenset])
 
     collectone(repo.manifest)
     for fname in files:
         collectone(repo.file(fname))
 
     return s
 
 def strip(ui, repo, nodelist, backup=True, topic='backup'):
 
     # Simple way to maintain backwards compatibility for this
     # argument.
     if backup in ['none', 'strip']:
         backup = False
 
     repo = repo.unfiltered()
     repo.destroying()
 
     cl = repo.changelog
     # TODO handle undo of merge sets
     if isinstance(nodelist, str):
         nodelist = [nodelist]
     striplist = [cl.rev(node) for node in nodelist]
     striprev = min(striplist)
 
     # Some revisions with rev > striprev may not be descendants of striprev.
     # We have to find these revisions and put them in a bundle, so that
     # we can restore them after the truncations.
     # To create the bundle we use repo.changegroupsubset which requires
     # the list of heads and bases of the set of interesting revisions.
     # (head = revision in the set that has no descendant in the set;
     #  base = revision in the set that has no ancestor in the set)
     tostrip = set(striplist)
     for rev in striplist:
         for desc in cl.descendants([rev]):
             tostrip.add(desc)
 
     files = _collectfiles(repo, striprev)
     saverevs = _collectbrokencsets(repo, files, striprev)
 
     # compute heads
     saveheads = set(saverevs)
     for r in xrange(striprev + 1, len(cl)):
         if r not in tostrip:
             saverevs.add(r)
             saveheads.difference_update(cl.parentrevs(r))
             saveheads.add(r)
     saveheads = [cl.node(r) for r in saveheads]
 
     # compute base nodes
     if saverevs:
         descendants = set(cl.descendants(saverevs))
         saverevs.difference_update(descendants)
     savebases = [cl.node(r) for r in saverevs]
     stripbases = [cl.node(r) for r in tostrip]
 
     # For a set s, max(parents(s) - s) is the same as max(heads(::s - s)), but
     # is much faster
     newbmtarget = repo.revs('max(parents(%ld) - (%ld))', tostrip, tostrip)
     if newbmtarget:
-        newbmtarget = repo[newbmtarget[0]].node()
+        newbmtarget = repo[newbmtarget.first()].node()
     else:
         newbmtarget = '.'
 
     bm = repo._bookmarks
     updatebm = []
     for m in bm:
         rev = repo[bm[m]].rev()
         if rev in tostrip:
             updatebm.append(m)
 
     # create a changegroup for all the branches we need to keep
     backupfile = None
     vfs = repo.vfs
     if backup:
         backupfile = _bundle(repo, stripbases, cl.heads(), node, topic)
         repo.ui.status(_("saved backup bundle to %s\n") %
                        vfs.join(backupfile))
         repo.ui.log("backupbundle", "saved backup bundle to %s\n",
                     vfs.join(backupfile))
     if saveheads or savebases:
         # do not compress partial bundle if we remove it from disk later
         chgrpfile = _bundle(repo, savebases, saveheads, node, 'temp',
                             compress=False)
 
     mfst = repo.manifest
 
     tr = repo.transaction("strip")
     offset = len(tr.entries)
 
     try:
         tr.startgroup()
         cl.strip(striprev, tr)
         mfst.strip(striprev, tr)
         for fn in files:
             repo.file(fn).strip(striprev, tr)
         tr.endgroup()
 
         try:
             for i in xrange(offset, len(tr.entries)):
                 file, troffset, ignore = tr.entries[i]
                 repo.sopener(file, 'a').truncate(troffset)
                 if troffset == 0:
                     repo.store.markremoved(file)
             tr.close()
         except: # re-raises
             tr.abort()
             raise
 
         if saveheads or savebases:
             ui.note(_("adding branch\n"))
             f = vfs.open(chgrpfile, "rb")
             gen = exchange.readbundle(ui, f, chgrpfile, vfs)
             if not repo.ui.verbose:
                 # silence internal shuffling chatter
                 repo.ui.pushbuffer()
             changegroup.addchangegroup(repo, gen, 'strip',
                                        'bundle:' + vfs.join(chgrpfile), True)
             if not repo.ui.verbose:
                 repo.ui.popbuffer()
             f.close()
 
         # remove undo files
         for undovfs, undofile in repo.undofiles():
             try:
                 undovfs.unlink(undofile)
             except OSError, e:
                 if e.errno != errno.ENOENT:
                     ui.warn(_('error removing %s: %s\n') %
                             (undovfs.join(undofile), str(e)))
 
         for m in updatebm:
             bm[m] = repo[newbmtarget].node()
         bm.write()
     except: # re-raises
         if backupfile:
             ui.warn(_("strip failed, full bundle stored in '%s'\n")
                     % vfs.join(backupfile))
         elif saveheads:
             ui.warn(_("strip failed, partial bundle stored in '%s'\n")
                     % vfs.join(chgrpfile))
         raise
     else:
         if saveheads or savebases:
             # Remove partial backup only if there were no exceptions
             vfs.unlink(chgrpfile)
 
     repo.destroyed()