track-tags: introduce first bits of tags tracking during transaction

This changeset introduces detection of tags changes during transaction. When
this happens a 'tag_moved=1' argument is set for hooks, similar to what we do
for bookmarks and phases.

This code is disabled by default as there are still various performance
concerns.  Some require a smarter use of our existing tag caches and some other
require rework around the transaction logic to skip execution when unneeded.
These performance improvements have been delayed, I would like to be able to
experiment and stabilize the feature behavior first.

Later changesets will push the concept further and provide a way for hooks to
know what are the actual changes introduced by the transaction. Similar work
is needed for the other families of changes (bookmark, phase, obsolescence,
etc). Upgrade of the transaction logic will likely be performed at the same
time.

The current code can report some false positive when .hgtags file changes but
resulting tags are unchanged. This will be fixed in the next changeset.

For testing, we simply globally enable a hook in the tag test as all the
possible tag update cases should exist there. A couple of them show the false
positive mentioned above.

See in code documentation for more details.

mercurial/localrepo.py

@@ -1,1986 +1,2032 b''
 # localrepo.py - read/write repository class for mercurial
 #
 # Copyright 2005-2007 Matt Mackall <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
 from __future__ import absolute_import
 
 import errno
 import hashlib
 import inspect
 import os
 import random
 import time
 import weakref
 
 from .i18n import _
 from .node import (
     hex,
     nullid,
     short,
     wdirrev,
 )
 from . import (
     bookmarks,
     branchmap,
     bundle2,
     changegroup,
     changelog,
     color,
     context,
     dirstate,
     dirstateguard,
     encoding,
     error,
     exchange,
     extensions,
     filelog,
     hook,
     lock as lockmod,
     manifest,
     match as matchmod,
     merge as mergemod,
     mergeutil,
     namespaces,
     obsolete,
     pathutil,
     peer,
     phases,
     pushkey,
     pycompat,
     repoview,
     revset,
     revsetlang,
     scmutil,
     store,
     subrepo,
     tags as tagsmod,
     transaction,
     txnutil,
     util,
     vfs as vfsmod,
 )
 
 release = lockmod.release
 urlerr = util.urlerr
 urlreq = util.urlreq
 
 class repofilecache(scmutil.filecache):
     """All filecache usage on repo are done for logic that should be unfiltered
     """
 
     def join(self, obj, fname):
         return obj.vfs.join(fname)
     def __get__(self, repo, type=None):
         if repo is None:
             return self
         return super(repofilecache, self).__get__(repo.unfiltered(), type)
     def __set__(self, repo, value):
         return super(repofilecache, self).__set__(repo.unfiltered(), value)
     def __delete__(self, repo):
         return super(repofilecache, self).__delete__(repo.unfiltered())
 
 class storecache(repofilecache):
     """filecache for files in the store"""
     def join(self, obj, fname):
         return obj.sjoin(fname)
 
 class unfilteredpropertycache(util.propertycache):
     """propertycache that apply to unfiltered repo only"""
 
     def __get__(self, repo, type=None):
         unfi = repo.unfiltered()
         if unfi is repo:
             return super(unfilteredpropertycache, self).__get__(unfi)
         return getattr(unfi, self.name)
 
 class filteredpropertycache(util.propertycache):
     """propertycache that must take filtering in account"""
 
     def cachevalue(self, obj, value):
         object.__setattr__(obj, self.name, value)
 
 
 def hasunfilteredcache(repo, name):
     """check if a repo has an unfilteredpropertycache value for <name>"""
     return name in vars(repo.unfiltered())
 
 def unfilteredmethod(orig):
     """decorate method that always need to be run on unfiltered version"""
     def wrapper(repo, *args, **kwargs):
         return orig(repo.unfiltered(), *args, **kwargs)
     return wrapper
 
 moderncaps = set(('lookup', 'branchmap', 'pushkey', 'known', 'getbundle',
                   'unbundle'))
 legacycaps = moderncaps.union(set(['changegroupsubset']))
 
 class localpeer(peer.peerrepository):
     '''peer for a local repo; reflects only the most recent API'''
 
     def __init__(self, repo, caps=None):
         if caps is None:
             caps = moderncaps.copy()
         peer.peerrepository.__init__(self)
         self._repo = repo.filtered('served')
         self.ui = repo.ui
         self._caps = repo._restrictcapabilities(caps)
         self.requirements = repo.requirements
         self.supportedformats = repo.supportedformats
 
     def close(self):
         self._repo.close()
 
     def _capabilities(self):
         return self._caps
 
     def local(self):
         return self._repo
 
     def canpush(self):
         return True
 
     def url(self):
         return self._repo.url()
 
     def lookup(self, key):
         return self._repo.lookup(key)
 
     def branchmap(self):
         return self._repo.branchmap()
 
     def heads(self):
         return self._repo.heads()
 
     def known(self, nodes):
         return self._repo.known(nodes)
 
     def getbundle(self, source, heads=None, common=None, bundlecaps=None,
                   **kwargs):
         chunks = exchange.getbundlechunks(self._repo, source, heads=heads,
                                           common=common, bundlecaps=bundlecaps,
                                           **kwargs)
         cb = util.chunkbuffer(chunks)
 
         if bundlecaps is not None and 'HG20' in bundlecaps:
             # When requesting a bundle2, getbundle returns a stream to make the
             # wire level function happier. We need to build a proper object
             # from it in local peer.
             return bundle2.getunbundler(self.ui, cb)
         else:
             return changegroup.getunbundler('01', cb, None)
 
     # TODO We might want to move the next two calls into legacypeer and add
     # unbundle instead.
 
     def unbundle(self, cg, heads, url):
         """apply a bundle on a repo
 
         This function handles the repo locking itself."""
         try:
             try:
                 cg = exchange.readbundle(self.ui, cg, None)
                 ret = exchange.unbundle(self._repo, cg, heads, 'push', url)
                 if util.safehasattr(ret, 'getchunks'):
                     # This is a bundle20 object, turn it into an unbundler.
                     # This little dance should be dropped eventually when the
                     # API is finally improved.
                     stream = util.chunkbuffer(ret.getchunks())
                     ret = bundle2.getunbundler(self.ui, stream)
                 return ret
             except Exception as exc:
                 # If the exception contains output salvaged from a bundle2
                 # reply, we need to make sure it is printed before continuing
                 # to fail. So we build a bundle2 with such output and consume
                 # it directly.
                 #
                 # This is not very elegant but allows a "simple" solution for
                 # issue4594
                 output = getattr(exc, '_bundle2salvagedoutput', ())
                 if output:
                     bundler = bundle2.bundle20(self._repo.ui)
                     for out in output:
                         bundler.addpart(out)
                     stream = util.chunkbuffer(bundler.getchunks())
                     b = bundle2.getunbundler(self.ui, stream)
                     bundle2.processbundle(self._repo, b)
                 raise
         except error.PushRaced as exc:
             raise error.ResponseError(_('push failed:'), str(exc))
 
     def lock(self):
         return self._repo.lock()
 
     def addchangegroup(self, cg, source, url):
         return cg.apply(self._repo, source, url)
 
     def pushkey(self, namespace, key, old, new):
         return self._repo.pushkey(namespace, key, old, new)
 
     def listkeys(self, namespace):
         return self._repo.listkeys(namespace)
 
     def debugwireargs(self, one, two, three=None, four=None, five=None):
         '''used to test argument passing over the wire'''
         return "%s %s %s %s %s" % (one, two, three, four, five)
 
 class locallegacypeer(localpeer):
     '''peer extension which implements legacy methods too; used for tests with
     restricted capabilities'''
 
     def __init__(self, repo):
         localpeer.__init__(self, repo, caps=legacycaps)
 
     def branches(self, nodes):
         return self._repo.branches(nodes)
 
     def between(self, pairs):
         return self._repo.between(pairs)
 
     def changegroup(self, basenodes, source):
         return changegroup.changegroup(self._repo, basenodes, source)
 
     def changegroupsubset(self, bases, heads, source):
         return changegroup.changegroupsubset(self._repo, bases, heads, source)
 
 class localrepository(object):
 
     supportedformats = set(('revlogv1', 'generaldelta', 'treemanifest',
                             'manifestv2'))
     _basesupported = supportedformats | set(('store', 'fncache', 'shared',
                                              'relshared', 'dotencode'))
     openerreqs = set(('revlogv1', 'generaldelta', 'treemanifest', 'manifestv2'))
     filtername = None
 
     # a list of (ui, featureset) functions.
     # only functions defined in module of enabled extensions are invoked
     featuresetupfuncs = set()
 
     def __init__(self, baseui, path, create=False):
         self.requirements = set()
         # wvfs: rooted at the repository root, used to access the working copy
         self.wvfs = vfsmod.vfs(path, expandpath=True, realpath=True)
         # vfs: rooted at .hg, used to access repo files outside of .hg/store
         self.vfs = None
         # svfs: usually rooted at .hg/store, used to access repository history
         # If this is a shared repository, this vfs may point to another
         # repository's .hg/store directory.
         self.svfs = None
         self.root = self.wvfs.base
         self.path = self.wvfs.join(".hg")
         self.origroot = path
         self.auditor = pathutil.pathauditor(self.root, self._checknested)
         self.nofsauditor = pathutil.pathauditor(self.root, self._checknested,
                                                 realfs=False)
         self.vfs = vfsmod.vfs(self.path)
         self.baseui = baseui
         self.ui = baseui.copy()
         self.ui.copy = baseui.copy # prevent copying repo configuration
         # A list of callback to shape the phase if no data were found.
         # Callback are in the form: func(repo, roots) --> processed root.
         # This list it to be filled by extension during repo setup
         self._phasedefaults = []
         try:
             self.ui.readconfig(self.vfs.join("hgrc"), self.root)
             self._loadextensions()
         except IOError:
             pass
 
         if self.featuresetupfuncs:
             self.supported = set(self._basesupported) # use private copy
             extmods = set(m.__name__ for n, m
                           in extensions.extensions(self.ui))
             for setupfunc in self.featuresetupfuncs:
                 if setupfunc.__module__ in extmods:
                     setupfunc(self.ui, self.supported)
         else:
             self.supported = self._basesupported
         color.setup(self.ui)
 
         # Add compression engines.
         for name in util.compengines:
             engine = util.compengines[name]
             if engine.revlogheader():
                 self.supported.add('exp-compression-%s' % name)
 
         if not self.vfs.isdir():
             if create:
                 self.requirements = newreporequirements(self)
 
                 if not self.wvfs.exists():
                     self.wvfs.makedirs()
                 self.vfs.makedir(notindexed=True)
 
                 if 'store' in self.requirements:
                     self.vfs.mkdir("store")
 
                     # create an invalid changelog
                     self.vfs.append(
                         "00changelog.i",
                         '\0\0\0\2' # represents revlogv2
                         ' dummy changelog to prevent using the old repo layout'
                     )
             else:
                 raise error.RepoError(_("repository %s not found") % path)
         elif create:
             raise error.RepoError(_("repository %s already exists") % path)
         else:
             try:
                 self.requirements = scmutil.readrequires(
                         self.vfs, self.supported)
             except IOError as inst:
                 if inst.errno != errno.ENOENT:
                     raise
 
         self.sharedpath = self.path
         try:
             sharedpath = self.vfs.read("sharedpath").rstrip('\n')
             if 'relshared' in self.requirements:
                 sharedpath = self.vfs.join(sharedpath)
             vfs = vfsmod.vfs(sharedpath, realpath=True)
             s = vfs.base
             if not vfs.exists():
                 raise error.RepoError(
                     _('.hg/sharedpath points to nonexistent directory %s') % s)
             self.sharedpath = s
         except IOError as inst:
             if inst.errno != errno.ENOENT:
                 raise
 
         self.store = store.store(
                 self.requirements, self.sharedpath, vfsmod.vfs)
         self.spath = self.store.path
         self.svfs = self.store.vfs
         self.sjoin = self.store.join
         self.vfs.createmode = self.store.createmode
         self._applyopenerreqs()
         if create:
             self._writerequirements()
 
         self._dirstatevalidatewarned = False
 
         self._branchcaches = {}
         self._revbranchcache = None
         self.filterpats = {}
         self._datafilters = {}
         self._transref = self._lockref = self._wlockref = None
 
         # A cache for various files under .hg/ that tracks file changes,
         # (used by the filecache decorator)
         #
         # Maps a property name to its util.filecacheentry
         self._filecache = {}
 
         # hold sets of revision to be filtered
         # should be cleared when something might have changed the filter value:
         # - new changesets,
         # - phase change,
         # - new obsolescence marker,
         # - working directory parent change,
         # - bookmark changes
         self.filteredrevcache = {}
 
         # generic mapping between names and nodes
         self.names = namespaces.namespaces()
 
     @property
     def wopener(self):
         self.ui.deprecwarn("use 'repo.wvfs' instead of 'repo.wopener'", '4.2')
         return self.wvfs
 
     @property
     def opener(self):
         self.ui.deprecwarn("use 'repo.vfs' instead of 'repo.opener'", '4.2')
         return self.vfs
 
     def close(self):
         self._writecaches()
 
     def _loadextensions(self):
         extensions.loadall(self.ui)
 
     def _writecaches(self):
         if self._revbranchcache:
             self._revbranchcache.write()
 
     def _restrictcapabilities(self, caps):
         if self.ui.configbool('experimental', 'bundle2-advertise', True):
             caps = set(caps)
             capsblob = bundle2.encodecaps(bundle2.getrepocaps(self))
             caps.add('bundle2=' + urlreq.quote(capsblob))
         return caps
 
     def _applyopenerreqs(self):
         self.svfs.options = dict((r, 1) for r in self.requirements
                                            if r in self.openerreqs)
         # experimental config: format.chunkcachesize
         chunkcachesize = self.ui.configint('format', 'chunkcachesize')
         if chunkcachesize is not None:
             self.svfs.options['chunkcachesize'] = chunkcachesize
         # experimental config: format.maxchainlen
         maxchainlen = self.ui.configint('format', 'maxchainlen')
         if maxchainlen is not None:
             self.svfs.options['maxchainlen'] = maxchainlen
         # experimental config: format.manifestcachesize
         manifestcachesize = self.ui.configint('format', 'manifestcachesize')
         if manifestcachesize is not None:
             self.svfs.options['manifestcachesize'] = manifestcachesize
         # experimental config: format.aggressivemergedeltas
         aggressivemergedeltas = self.ui.configbool('format',
             'aggressivemergedeltas', False)
         self.svfs.options['aggressivemergedeltas'] = aggressivemergedeltas
         self.svfs.options['lazydeltabase'] = not scmutil.gddeltaconfig(self.ui)
 
         for r in self.requirements:
             if r.startswith('exp-compression-'):
                 self.svfs.options['compengine'] = r[len('exp-compression-'):]
 
     def _writerequirements(self):
         scmutil.writerequires(self.vfs, self.requirements)
 
     def _checknested(self, path):
         """Determine if path is a legal nested repository."""
         if not path.startswith(self.root):
             return False
         subpath = path[len(self.root) + 1:]
         normsubpath = util.pconvert(subpath)
 
         # XXX: Checking against the current working copy is wrong in
         # the sense that it can reject things like
         #
         #   $ hg cat -r 10 sub/x.txt
         #
         # if sub/ is no longer a subrepository in the working copy
         # parent revision.
         #
         # However, it can of course also allow things that would have
         # been rejected before, such as the above cat command if sub/
         # is a subrepository now, but was a normal directory before.
         # The old path auditor would have rejected by mistake since it
         # panics when it sees sub/.hg/.
         #
         # All in all, checking against the working copy seems sensible
         # since we want to prevent access to nested repositories on
         # the filesystem *now*.
         ctx = self[None]
         parts = util.splitpath(subpath)
         while parts:
             prefix = '/'.join(parts)
             if prefix in ctx.substate:
                 if prefix == normsubpath:
                     return True
                 else:
                     sub = ctx.sub(prefix)
                     return sub.checknested(subpath[len(prefix) + 1:])
             else:
                 parts.pop()
         return False
 
     def peer(self):
         return localpeer(self) # not cached to avoid reference cycle
 
     def unfiltered(self):
         """Return unfiltered version of the repository
 
         Intended to be overwritten by filtered repo."""
         return self
 
     def filtered(self, name):
         """Return a filtered version of a repository"""
         # build a new class with the mixin and the current class
         # (possibly subclass of the repo)
         class filteredrepo(repoview.repoview, self.unfiltered().__class__):
             pass
         return filteredrepo(self, name)
 
     @repofilecache('bookmarks', 'bookmarks.current')
     def _bookmarks(self):
         return bookmarks.bmstore(self)
 
     @property
     def _activebookmark(self):
         return self._bookmarks.active
 
     def bookmarkheads(self, bookmark):
         name = bookmark.split('@', 1)[0]
         heads = []
         for mark, n in self._bookmarks.iteritems():
             if mark.split('@', 1)[0] == name:
                 heads.append(n)
         return heads
 
     # _phaserevs and _phasesets depend on changelog. what we need is to
     # call _phasecache.invalidate() if '00changelog.i' was changed, but it
     # can't be easily expressed in filecache mechanism.
     @storecache('phaseroots', '00changelog.i')
     def _phasecache(self):
         return phases.phasecache(self, self._phasedefaults)
 
     @storecache('obsstore')
     def obsstore(self):
         # read default format for new obsstore.
         # developer config: format.obsstore-version
         defaultformat = self.ui.configint('format', 'obsstore-version', None)
         # rely on obsstore class default when possible.
         kwargs = {}
         if defaultformat is not None:
             kwargs['defaultformat'] = defaultformat
         readonly = not obsolete.isenabled(self, obsolete.createmarkersopt)
         store = obsolete.obsstore(self.svfs, readonly=readonly,
                                   **kwargs)
         if store and readonly:
             self.ui.warn(
                 _('obsolete feature not enabled but %i markers found!\n')
                 % len(list(store)))
         return store
 
     @storecache('00changelog.i')
     def changelog(self):
         c = changelog.changelog(self.svfs)
         if txnutil.mayhavepending(self.root):
             c.readpending('00changelog.i.a')
         return c
 
     def _constructmanifest(self):
         # This is a temporary function while we migrate from manifest to
         # manifestlog. It allows bundlerepo and unionrepo to intercept the
         # manifest creation.
         return manifest.manifestrevlog(self.svfs)
 
     @storecache('00manifest.i')
     def manifestlog(self):
         return manifest.manifestlog(self.svfs, self)
 
     @repofilecache('dirstate')
     def dirstate(self):
         return dirstate.dirstate(self.vfs, self.ui, self.root,
                                  self._dirstatevalidate)
 
     def _dirstatevalidate(self, node):
         try:
             self.changelog.rev(node)
             return node
         except error.LookupError:
             if not self._dirstatevalidatewarned:
                 self._dirstatevalidatewarned = True
                 self.ui.warn(_("warning: ignoring unknown"
                                " working parent %s!\n") % short(node))
             return nullid
 
     def __getitem__(self, changeid):
         if changeid is None or changeid == wdirrev:
             return context.workingctx(self)
         if isinstance(changeid, slice):
             return [context.changectx(self, i)
                     for i in xrange(*changeid.indices(len(self)))
                     if i not in self.changelog.filteredrevs]
         return context.changectx(self, changeid)
 
     def __contains__(self, changeid):
         try:
             self[changeid]
             return True
         except error.RepoLookupError:
             return False
 
     def __nonzero__(self):
         return True
 
     __bool__ = __nonzero__
 
     def __len__(self):
         return len(self.changelog)
 
     def __iter__(self):
         return iter(self.changelog)
 
     def revs(self, expr, *args):
         '''Find revisions matching a revset.
 
         The revset is specified as a string ``expr`` that may contain
         %-formatting to escape certain types. See ``revsetlang.formatspec``.
 
         Revset aliases from the configuration are not expanded. To expand
         user aliases, consider calling ``scmutil.revrange()`` or
         ``repo.anyrevs([expr], user=True)``.
 
         Returns a revset.abstractsmartset, which is a list-like interface
         that contains integer revisions.
         '''
         expr = revsetlang.formatspec(expr, *args)
         m = revset.match(None, expr)
         return m(self)
 
     def set(self, expr, *args):
         '''Find revisions matching a revset and emit changectx instances.
 
         This is a convenience wrapper around ``revs()`` that iterates the
         result and is a generator of changectx instances.
 
         Revset aliases from the configuration are not expanded. To expand
         user aliases, consider calling ``scmutil.revrange()``.
         '''
         for r in self.revs(expr, *args):
             yield self[r]
 
     def anyrevs(self, specs, user=False):
         '''Find revisions matching one of the given revsets.
 
         Revset aliases from the configuration are not expanded by default. To
         expand user aliases, specify ``user=True``.
         '''
         if user:
             m = revset.matchany(self.ui, specs, repo=self)
         else:
             m = revset.matchany(None, specs)
         return m(self)
 
     def url(self):
         return 'file:' + self.root
 
     def hook(self, name, throw=False, **args):
         """Call a hook, passing this repo instance.
 
         This a convenience method to aid invoking hooks. Extensions likely
         won't call this unless they have registered a custom hook or are
         replacing code that is expected to call a hook.
         """
         return hook.hook(self.ui, self, name, throw, **args)
 
     def tag(self, names, node, message, local, user, date, editor=False):
         self.ui.deprecwarn("use 'tagsmod.tag' instead of 'repo.tag'", '4.2')
         tagsmod.tag(self, names, node, message, local, user, date,
                     editor=editor)
 
     @filteredpropertycache
     def _tagscache(self):
         '''Returns a tagscache object that contains various tags related
         caches.'''
 
         # This simplifies its cache management by having one decorated
         # function (this one) and the rest simply fetch things from it.
         class tagscache(object):
             def __init__(self):
                 # These two define the set of tags for this repository. tags
                 # maps tag name to node; tagtypes maps tag name to 'global' or
                 # 'local'. (Global tags are defined by .hgtags across all
                 # heads, and local tags are defined in .hg/localtags.)
                 # They constitute the in-memory cache of tags.
                 self.tags = self.tagtypes = None
 
                 self.nodetagscache = self.tagslist = None
 
         cache = tagscache()
         cache.tags, cache.tagtypes = self._findtags()
 
         return cache
 
     def tags(self):
         '''return a mapping of tag to node'''
         t = {}
         if self.changelog.filteredrevs:
             tags, tt = self._findtags()
         else:
             tags = self._tagscache.tags
         for k, v in tags.iteritems():
             try:
                 # ignore tags to unknown nodes
                 self.changelog.rev(v)
                 t[k] = v
             except (error.LookupError, ValueError):
                 pass
         return t
 
     def _findtags(self):
         '''Do the hard work of finding tags.  Return a pair of dicts
         (tags, tagtypes) where tags maps tag name to node, and tagtypes
         maps tag name to a string like \'global\' or \'local\'.
         Subclasses or extensions are free to add their own tags, but
         should be aware that the returned dicts will be retained for the
         duration of the localrepo object.'''
 
         # XXX what tagtype should subclasses/extensions use?  Currently
         # mq and bookmarks add tags, but do not set the tagtype at all.
         # Should each extension invent its own tag type?  Should there
         # be one tagtype for all such "virtual" tags?  Or is the status
         # quo fine?
 
 
         # map tag name to (node, hist)
         alltags = tagsmod.findglobaltags(self.ui, self)
         # map tag name to tag type
         tagtypes = dict((tag, 'global') for tag in alltags)
 
         tagsmod.readlocaltags(self.ui, self, alltags, tagtypes)
 
         # Build the return dicts.  Have to re-encode tag names because
         # the tags module always uses UTF-8 (in order not to lose info
         # writing to the cache), but the rest of Mercurial wants them in
         # local encoding.
         tags = {}
         for (name, (node, hist)) in alltags.iteritems():
             if node != nullid:
                 tags[encoding.tolocal(name)] = node
         tags['tip'] = self.changelog.tip()
         tagtypes = dict([(encoding.tolocal(name), value)
                          for (name, value) in tagtypes.iteritems()])
         return (tags, tagtypes)
 
     def tagtype(self, tagname):
         '''
         return the type of the given tag. result can be:
 
         'local'  : a local tag
         'global' : a global tag
         None     : tag does not exist
         '''
 
         return self._tagscache.tagtypes.get(tagname)
 
     def tagslist(self):
         '''return a list of tags ordered by revision'''
         if not self._tagscache.tagslist:
             l = []
             for t, n in self.tags().iteritems():
                 l.append((self.changelog.rev(n), t, n))
             self._tagscache.tagslist = [(t, n) for r, t, n in sorted(l)]
 
         return self._tagscache.tagslist
 
     def nodetags(self, node):
         '''return the tags associated with a node'''
         if not self._tagscache.nodetagscache:
             nodetagscache = {}
             for t, n in self._tagscache.tags.iteritems():
                 nodetagscache.setdefault(n, []).append(t)
             for tags in nodetagscache.itervalues():
                 tags.sort()
             self._tagscache.nodetagscache = nodetagscache
         return self._tagscache.nodetagscache.get(node, [])
 
     def nodebookmarks(self, node):
         """return the list of bookmarks pointing to the specified node"""
         marks = []
         for bookmark, n in self._bookmarks.iteritems():
             if n == node:
                 marks.append(bookmark)
         return sorted(marks)
 
     def branchmap(self):
         '''returns a dictionary {branch: [branchheads]} with branchheads
         ordered by increasing revision number'''
         branchmap.updatecache(self)
         return self._branchcaches[self.filtername]
 
     @unfilteredmethod
     def revbranchcache(self):
         if not self._revbranchcache:
             self._revbranchcache = branchmap.revbranchcache(self.unfiltered())
         return self._revbranchcache
 
     def branchtip(self, branch, ignoremissing=False):
         '''return the tip node for a given branch
 
         If ignoremissing is True, then this method will not raise an error.
         This is helpful for callers that only expect None for a missing branch
         (e.g. namespace).
 
         '''
         try:
             return self.branchmap().branchtip(branch)
         except KeyError:
             if not ignoremissing:
                 raise error.RepoLookupError(_("unknown branch '%s'") % branch)
             else:
                 pass
 
     def lookup(self, key):
         return self[key].node()
 
     def lookupbranch(self, key, remote=None):
         repo = remote or self
         if key in repo.branchmap():
             return key
 
         repo = (remote and remote.local()) and remote or self
         return repo[key].branch()
 
     def known(self, nodes):
         cl = self.changelog
         nm = cl.nodemap
         filtered = cl.filteredrevs
         result = []
         for n in nodes:
             r = nm.get(n)
             resp = not (r is None or r in filtered)
             result.append(resp)
         return result
 
     def local(self):
         return self
 
     def publishing(self):
         # it's safe (and desirable) to trust the publish flag unconditionally
         # so that we don't finalize changes shared between users via ssh or nfs
         return self.ui.configbool('phases', 'publish', True, untrusted=True)
 
     def cancopy(self):
         # so statichttprepo's override of local() works
         if not self.local():
             return False
         if not self.publishing():
             return True
         # if publishing we can't copy if there is filtered content
         return not self.filtered('visible').changelog.filteredrevs
 
     def shared(self):
         '''the type of shared repository (None if not shared)'''
         if self.sharedpath != self.path:
             return 'store'
         return None
 
     def join(self, f, *insidef):
         self.ui.deprecwarn("use 'repo.vfs.join' instead of 'repo.join'", '4.2')
         return self.vfs.join(os.path.join(f, *insidef))
 
     def wjoin(self, f, *insidef):
         return self.vfs.reljoin(self.root, f, *insidef)
 
     def file(self, f):
         if f[0] == '/':
             f = f[1:]
         return filelog.filelog(self.svfs, f)
 
     def changectx(self, changeid):
         return self[changeid]
 
     def setparents(self, p1, p2=nullid):
         self.dirstate.beginparentchange()
         copies = self.dirstate.setparents(p1, p2)
         pctx = self[p1]
         if copies:
             # Adjust copy records, the dirstate cannot do it, it
             # requires access to parents manifests. Preserve them
             # only for entries added to first parent.
             for f in copies:
                 if f not in pctx and copies[f] in pctx:
                     self.dirstate.copy(copies[f], f)
         if p2 == nullid:
             for f, s in sorted(self.dirstate.copies().items()):
                 if f not in pctx and s not in pctx:
                     self.dirstate.copy(None, f)
         self.dirstate.endparentchange()
 
     def filectx(self, path, changeid=None, fileid=None):
         """changeid can be a changeset revision, node, or tag.
            fileid can be a file revision or node."""
         return context.filectx(self, path, changeid, fileid)
 
     def getcwd(self):
         return self.dirstate.getcwd()
 
     def pathto(self, f, cwd=None):
         return self.dirstate.pathto(f, cwd)
 
     def wfile(self, f, mode='r'):
         self.ui.deprecwarn("use 'repo.wvfs' instead of 'repo.wfile'", '4.2')
         return self.wvfs(f, mode)
 
     def _link(self, f):
         self.ui.deprecwarn("use 'repo.wvfs.islink' instead of 'repo._link'",
                            '4.2')
         return self.wvfs.islink(f)
 
     def _loadfilter(self, filter):
         if filter not in self.filterpats:
             l = []
             for pat, cmd in self.ui.configitems(filter):
                 if cmd == '!':
                     continue
                 mf = matchmod.match(self.root, '', [pat])
                 fn = None
                 params = cmd
                 for name, filterfn in self._datafilters.iteritems():
                     if cmd.startswith(name):
                         fn = filterfn
                         params = cmd[len(name):].lstrip()
                         break
                 if not fn:
                     fn = lambda s, c, **kwargs: util.filter(s, c)
                 # Wrap old filters not supporting keyword arguments
                 if not inspect.getargspec(fn)[2]:
                     oldfn = fn
                     fn = lambda s, c, **kwargs: oldfn(s, c)
                 l.append((mf, fn, params))
             self.filterpats[filter] = l
         return self.filterpats[filter]
 
     def _filter(self, filterpats, filename, data):
         for mf, fn, cmd in filterpats:
             if mf(filename):
                 self.ui.debug("filtering %s through %s\n" % (filename, cmd))
                 data = fn(data, cmd, ui=self.ui, repo=self, filename=filename)
                 break
 
         return data
 
     @unfilteredpropertycache
     def _encodefilterpats(self):
         return self._loadfilter('encode')
 
     @unfilteredpropertycache
     def _decodefilterpats(self):
         return self._loadfilter('decode')
 
     def adddatafilter(self, name, filter):
         self._datafilters[name] = filter
 
     def wread(self, filename):
         if self.wvfs.islink(filename):
             data = self.wvfs.readlink(filename)
         else:
             data = self.wvfs.read(filename)
         return self._filter(self._encodefilterpats, filename, data)
 
     def wwrite(self, filename, data, flags, backgroundclose=False):
         """write ``data`` into ``filename`` in the working directory
 
         This returns length of written (maybe decoded) data.
         """
         data = self._filter(self._decodefilterpats, filename, data)
         if 'l' in flags:
             self.wvfs.symlink(data, filename)
         else:
             self.wvfs.write(filename, data, backgroundclose=backgroundclose)
             if 'x' in flags:
                 self.wvfs.setflags(filename, False, True)
         return len(data)
 
     def wwritedata(self, filename, data):
         return self._filter(self._decodefilterpats, filename, data)
 
     def currenttransaction(self):
         """return the current transaction or None if non exists"""
         if self._transref:
             tr = self._transref()
         else:
             tr = None
 
         if tr and tr.running():
             return tr
         return None
 
     def transaction(self, desc, report=None):
         if (self.ui.configbool('devel', 'all-warnings')
                 or self.ui.configbool('devel', 'check-locks')):
             if self._currentlock(self._lockref) is None:
                 raise error.ProgrammingError('transaction requires locking')
         tr = self.currenttransaction()
         if tr is not None:
             return tr.nest()
 
         # abort here if the journal already exists
         if self.svfs.exists("journal"):
             raise error.RepoError(
                 _("abandoned transaction found"),
                 hint=_("run 'hg recover' to clean up transaction"))
 
         idbase = "%.40f#%f" % (random.random(), time.time())
         ha = hex(hashlib.sha1(idbase).digest())
         txnid = 'TXN:' + ha
         self.hook('pretxnopen', throw=True, txnname=desc, txnid=txnid)
 
         self._writejournal(desc)
         renames = [(vfs, x, undoname(x)) for vfs, x in self._journalfiles()]
         if report:
             rp = report
         else:
             rp = self.ui.warn
         vfsmap = {'plain': self.vfs} # root of .hg/
         # we must avoid cyclic reference between repo and transaction.
         reporef = weakref.ref(self)
-        def validate(tr):
+        # Code to track tag movement
+        #
+        # Since tags are all handled as file content, it is actually quite hard
+        # to track these movement from a code perspective. So we fallback to a
+        # tracking at the repository level. One could envision to track changes
+        # to the '.hgtags' file through changegroup apply but that fails to
+        # cope with case where transaction expose new heads without changegroup
+        # being involved (eg: phase movement).
+        #
+        # For now, We gate the feature behind a flag since this likely comes
+        # with performance impacts. The current code run more often than needed
+        # and do not use caches as much as it could.  The current focus is on
+        # the behavior of the feature so we disable it by default. The flag
+        # will be removed when we are happy with the performance impact.
+        tracktags = lambda x: None
+        # experimental config: experimental.hook-track-tags
+        shouldtracktags = self.ui.configbool('experimental', 'hook-track-tags',
+                                             False)
+        if desc != 'strip' and shouldtracktags:
+            oldheads = self.changelog.headrevs()
+            def tracktags(tr2):
+                repo = reporef()
+                oldfnodes = tagsmod.fnoderevs(repo.ui, repo, oldheads)
+                newheads = repo.changelog.headrevs()
+                newfnodes = tagsmod.fnoderevs(repo.ui, repo, newheads)
+                # notes: we compare lists here.
+                # As we do it only once buiding set would not be cheaper
+                if oldfnodes != newfnodes:
+                    tr2.hookargs['tag_moved'] = '1'
+        def validate(tr2):
             """will run pre-closing hooks"""
+            # XXX the transaction API is a bit lacking here so we take a hacky
+            # path for now
+            #
+            # We cannot add this as a "pending" hooks since the 'tr.hookargs'
+            # dict is copied before these run. In addition we needs the data
+            # available to in memory hooks too.
+            #
+            # Moreover, we also need to make sure this runs before txnclose
+            # hooks and there is no "pending" mechanism that would execute
+            # logic only if hooks are about to run.
+            #
+            # Fixing this limitation of the transaction is also needed to track
+            # other families of changes (bookmarks, phases, obsolescence).
+            #
+            # This will have to be fixed before we remove the experimental
+            # gating.
+            tracktags(tr2)
             reporef().hook('pretxnclose', throw=True,
                            txnname=desc, **pycompat.strkwargs(tr.hookargs))
         def releasefn(tr, success):
             repo = reporef()
             if success:
                 # this should be explicitly invoked here, because
                 # in-memory changes aren't written out at closing
                 # transaction, if tr.addfilegenerator (via
                 # dirstate.write or so) isn't invoked while
                 # transaction running
                 repo.dirstate.write(None)
             else:
                 # discard all changes (including ones already written
                 # out) in this transaction
                 repo.dirstate.restorebackup(None, prefix='journal.')
 
                 repo.invalidate(clearfilecache=True)
 
         tr = transaction.transaction(rp, self.svfs, vfsmap,
                                      "journal",
                                      "undo",
                                      aftertrans(renames),
                                      self.store.createmode,
                                      validator=validate,
                                      releasefn=releasefn)
 
         tr.hookargs['txnid'] = txnid
         # note: writing the fncache only during finalize mean that the file is
         # outdated when running hooks. As fncache is used for streaming clone,
         # this is not expected to break anything that happen during the hooks.
         tr.addfinalize('flush-fncache', self.store.write)
         def txnclosehook(tr2):
             """To be run if transaction is successful, will schedule a hook run
             """
             # Don't reference tr2 in hook() so we don't hold a reference.
             # This reduces memory consumption when there are multiple
             # transactions per lock. This can likely go away if issue5045
             # fixes the function accumulation.
             hookargs = tr2.hookargs
 
             def hook():
                 reporef().hook('txnclose', throw=False, txnname=desc,
                                **pycompat.strkwargs(hookargs))
             reporef()._afterlock(hook)
         tr.addfinalize('txnclose-hook', txnclosehook)
         def txnaborthook(tr2):
             """To be run if transaction is aborted
             """
             reporef().hook('txnabort', throw=False, txnname=desc,
                            **tr2.hookargs)
         tr.addabort('txnabort-hook', txnaborthook)
         # avoid eager cache invalidation. in-memory data should be identical
         # to stored data if transaction has no error.
         tr.addpostclose('refresh-filecachestats', self._refreshfilecachestats)
         self._transref = weakref.ref(tr)
         return tr
 
     def _journalfiles(self):
         return ((self.svfs, 'journal'),
                 (self.vfs, 'journal.dirstate'),
                 (self.vfs, 'journal.branch'),
                 (self.vfs, 'journal.desc'),
                 (self.vfs, 'journal.bookmarks'),
                 (self.svfs, 'journal.phaseroots'))
 
     def undofiles(self):
         return [(vfs, undoname(x)) for vfs, x in self._journalfiles()]
 
     def _writejournal(self, desc):
         self.dirstate.savebackup(None, prefix='journal.')
         self.vfs.write("journal.branch",
                           encoding.fromlocal(self.dirstate.branch()))
         self.vfs.write("journal.desc",
                           "%d\n%s\n" % (len(self), desc))
         self.vfs.write("journal.bookmarks",
                           self.vfs.tryread("bookmarks"))
         self.svfs.write("journal.phaseroots",
                            self.svfs.tryread("phaseroots"))
 
     def recover(self):
         with self.lock():
             if self.svfs.exists("journal"):
                 self.ui.status(_("rolling back interrupted transaction\n"))
                 vfsmap = {'': self.svfs,
                           'plain': self.vfs,}
                 transaction.rollback(self.svfs, vfsmap, "journal",
                                      self.ui.warn)
                 self.invalidate()
                 return True
             else:
                 self.ui.warn(_("no interrupted transaction available\n"))
                 return False
 
     def rollback(self, dryrun=False, force=False):
         wlock = lock = dsguard = None
         try:
             wlock = self.wlock()
             lock = self.lock()
             if self.svfs.exists("undo"):
                 dsguard = dirstateguard.dirstateguard(self, 'rollback')
 
                 return self._rollback(dryrun, force, dsguard)
             else:
                 self.ui.warn(_("no rollback information available\n"))
                 return 1
         finally:
             release(dsguard, lock, wlock)
 
     @unfilteredmethod # Until we get smarter cache management
     def _rollback(self, dryrun, force, dsguard):
         ui = self.ui
         try:
             args = self.vfs.read('undo.desc').splitlines()
             (oldlen, desc, detail) = (int(args[0]), args[1], None)
             if len(args) >= 3:
                 detail = args[2]
             oldtip = oldlen - 1
 
             if detail and ui.verbose:
                 msg = (_('repository tip rolled back to revision %s'
                          ' (undo %s: %s)\n')
                        % (oldtip, desc, detail))
             else:
                 msg = (_('repository tip rolled back to revision %s'
                          ' (undo %s)\n')
                        % (oldtip, desc))
         except IOError:
             msg = _('rolling back unknown transaction\n')
             desc = None
 
         if not force and self['.'] != self['tip'] and desc == 'commit':
             raise error.Abort(
                 _('rollback of last commit while not checked out '
                   'may lose data'), hint=_('use -f to force'))
 
         ui.status(msg)
         if dryrun:
             return 0
 
         parents = self.dirstate.parents()
         self.destroying()
         vfsmap = {'plain': self.vfs, '': self.svfs}
         transaction.rollback(self.svfs, vfsmap, 'undo', ui.warn)
         if self.vfs.exists('undo.bookmarks'):
             self.vfs.rename('undo.bookmarks', 'bookmarks', checkambig=True)
         if self.svfs.exists('undo.phaseroots'):
             self.svfs.rename('undo.phaseroots', 'phaseroots', checkambig=True)
         self.invalidate()
 
         parentgone = (parents[0] not in self.changelog.nodemap or
                       parents[1] not in self.changelog.nodemap)
         if parentgone:
             # prevent dirstateguard from overwriting already restored one
             dsguard.close()
 
             self.dirstate.restorebackup(None, prefix='undo.')
             try:
                 branch = self.vfs.read('undo.branch')
                 self.dirstate.setbranch(encoding.tolocal(branch))
             except IOError:
                 ui.warn(_('named branch could not be reset: '
                           'current branch is still \'%s\'\n')
                         % self.dirstate.branch())
 
             parents = tuple([p.rev() for p in self[None].parents()])
             if len(parents) > 1:
                 ui.status(_('working directory now based on '
                             'revisions %d and %d\n') % parents)
             else:
                 ui.status(_('working directory now based on '
                             'revision %d\n') % parents)
             mergemod.mergestate.clean(self, self['.'].node())
 
         # TODO: if we know which new heads may result from this rollback, pass
         # them to destroy(), which will prevent the branchhead cache from being
         # invalidated.
         self.destroyed()
         return 0
 
     def invalidatecaches(self):
 
         if '_tagscache' in vars(self):
             # can't use delattr on proxy
             del self.__dict__['_tagscache']
 
         self.unfiltered()._branchcaches.clear()
         self.invalidatevolatilesets()
 
     def invalidatevolatilesets(self):
         self.filteredrevcache.clear()
         obsolete.clearobscaches(self)
 
     def invalidatedirstate(self):
         '''Invalidates the dirstate, causing the next call to dirstate
         to check if it was modified since the last time it was read,
         rereading it if it has.
 
         This is different to dirstate.invalidate() that it doesn't always
         rereads the dirstate. Use dirstate.invalidate() if you want to
         explicitly read the dirstate again (i.e. restoring it to a previous
         known good state).'''
         if hasunfilteredcache(self, 'dirstate'):
             for k in self.dirstate._filecache:
                 try:
                     delattr(self.dirstate, k)
                 except AttributeError:
                     pass
             delattr(self.unfiltered(), 'dirstate')
 
     def invalidate(self, clearfilecache=False):
         '''Invalidates both store and non-store parts other than dirstate
 
         If a transaction is running, invalidation of store is omitted,
         because discarding in-memory changes might cause inconsistency
         (e.g. incomplete fncache causes unintentional failure, but
         redundant one doesn't).
         '''
         unfiltered = self.unfiltered() # all file caches are stored unfiltered
         for k in list(self._filecache.keys()):
             # dirstate is invalidated separately in invalidatedirstate()
             if k == 'dirstate':
                 continue
 
             if clearfilecache:
                 del self._filecache[k]
             try:
                 delattr(unfiltered, k)
             except AttributeError:
                 pass
         self.invalidatecaches()
         if not self.currenttransaction():
             # TODO: Changing contents of store outside transaction
             # causes inconsistency. We should make in-memory store
             # changes detectable, and abort if changed.
             self.store.invalidatecaches()
 
     def invalidateall(self):
         '''Fully invalidates both store and non-store parts, causing the
         subsequent operation to reread any outside changes.'''
         # extension should hook this to invalidate its caches
         self.invalidate()
         self.invalidatedirstate()
 
     @unfilteredmethod
     def _refreshfilecachestats(self, tr):
         """Reload stats of cached files so that they are flagged as valid"""
         for k, ce in self._filecache.items():
             if k == 'dirstate' or k not in self.__dict__:
                 continue
             ce.refresh()
 
     def _lock(self, vfs, lockname, wait, releasefn, acquirefn, desc,
               inheritchecker=None, parentenvvar=None):
         parentlock = None
         # the contents of parentenvvar are used by the underlying lock to
         # determine whether it can be inherited
         if parentenvvar is not None:
             parentlock = encoding.environ.get(parentenvvar)
         try:
             l = lockmod.lock(vfs, lockname, 0, releasefn=releasefn,
                              acquirefn=acquirefn, desc=desc,
                              inheritchecker=inheritchecker,
                              parentlock=parentlock)
         except error.LockHeld as inst:
             if not wait:
                 raise
             # show more details for new-style locks
             if ':' in inst.locker:
                 host, pid = inst.locker.split(":", 1)
                 self.ui.warn(
                     _("waiting for lock on %s held by process %r "
                       "on host %r\n") % (desc, pid, host))
             else:
                 self.ui.warn(_("waiting for lock on %s held by %r\n") %
                              (desc, inst.locker))
             # default to 600 seconds timeout
             l = lockmod.lock(vfs, lockname,
                              int(self.ui.config("ui", "timeout", "600")),
                              releasefn=releasefn, acquirefn=acquirefn,
                              desc=desc)
             self.ui.warn(_("got lock after %s seconds\n") % l.delay)
         return l
 
     def _afterlock(self, callback):
         """add a callback to be run when the repository is fully unlocked
 
         The callback will be executed when the outermost lock is released
         (with wlock being higher level than 'lock')."""
         for ref in (self._wlockref, self._lockref):
             l = ref and ref()
             if l and l.held:
                 l.postrelease.append(callback)
                 break
         else: # no lock have been found.
             callback()
 
     def lock(self, wait=True):
         '''Lock the repository store (.hg/store) and return a weak reference
         to the lock. Use this before modifying the store (e.g. committing or
         stripping). If you are opening a transaction, get a lock as well.)
 
         If both 'lock' and 'wlock' must be acquired, ensure you always acquires
         'wlock' first to avoid a dead-lock hazard.'''
         l = self._currentlock(self._lockref)
         if l is not None:
             l.lock()
             return l
 
         l = self._lock(self.svfs, "lock", wait, None,
                        self.invalidate, _('repository %s') % self.origroot)
         self._lockref = weakref.ref(l)
         return l
 
     def _wlockchecktransaction(self):
         if self.currenttransaction() is not None:
             raise error.LockInheritanceContractViolation(
                 'wlock cannot be inherited in the middle of a transaction')
 
     def wlock(self, wait=True):
         '''Lock the non-store parts of the repository (everything under
         .hg except .hg/store) and return a weak reference to the lock.
 
         Use this before modifying files in .hg.
 
         If both 'lock' and 'wlock' must be acquired, ensure you always acquires
         'wlock' first to avoid a dead-lock hazard.'''
         l = self._wlockref and self._wlockref()
         if l is not None and l.held:
             l.lock()
             return l
 
         # We do not need to check for non-waiting lock acquisition.  Such
         # acquisition would not cause dead-lock as they would just fail.
         if wait and (self.ui.configbool('devel', 'all-warnings')
                      or self.ui.configbool('devel', 'check-locks')):
             if self._currentlock(self._lockref) is not None:
                 self.ui.develwarn('"wlock" acquired after "lock"')
 
         def unlock():
             if self.dirstate.pendingparentchange():
                 self.dirstate.invalidate()
             else:
                 self.dirstate.write(None)
 
             self._filecache['dirstate'].refresh()
 
         l = self._lock(self.vfs, "wlock", wait, unlock,
                        self.invalidatedirstate, _('working directory of %s') %
                        self.origroot,
                        inheritchecker=self._wlockchecktransaction,
                        parentenvvar='HG_WLOCK_LOCKER')
         self._wlockref = weakref.ref(l)
         return l
 
     def _currentlock(self, lockref):
         """Returns the lock if it's held, or None if it's not."""
         if lockref is None:
             return None
         l = lockref()
         if l is None or not l.held:
             return None
         return l
 
     def currentwlock(self):
         """Returns the wlock if it's held, or None if it's not."""
         return self._currentlock(self._wlockref)
 
     def _filecommit(self, fctx, manifest1, manifest2, linkrev, tr, changelist):
         """
         commit an individual file as part of a larger transaction
         """
 
         fname = fctx.path()
         fparent1 = manifest1.get(fname, nullid)
         fparent2 = manifest2.get(fname, nullid)
         if isinstance(fctx, context.filectx):
             node = fctx.filenode()
             if node in [fparent1, fparent2]:
                 self.ui.debug('reusing %s filelog entry\n' % fname)
                 if manifest1.flags(fname) != fctx.flags():
                     changelist.append(fname)
                 return node
 
         flog = self.file(fname)
         meta = {}
         copy = fctx.renamed()
         if copy and copy[0] != fname:
             # Mark the new revision of this file as a copy of another
             # file.  This copy data will effectively act as a parent
             # of this new revision.  If this is a merge, the first
             # parent will be the nullid (meaning "look up the copy data")
             # and the second one will be the other parent.  For example:
             #
             # 0 --- 1 --- 3   rev1 changes file foo
             #   \       /     rev2 renames foo to bar and changes it
             #    \- 2 -/      rev3 should have bar with all changes and
             #                      should record that bar descends from
             #                      bar in rev2 and foo in rev1
             #
             # this allows this merge to succeed:
             #
             # 0 --- 1 --- 3   rev4 reverts the content change from rev2
             #   \       /     merging rev3 and rev4 should use bar@rev2
             #    \- 2 --- 4        as the merge base
             #
 
             cfname = copy[0]
             crev = manifest1.get(cfname)
             newfparent = fparent2
 
             if manifest2: # branch merge
                 if fparent2 == nullid or crev is None: # copied on remote side
                     if cfname in manifest2:
                         crev = manifest2[cfname]
                         newfparent = fparent1
 
             # Here, we used to search backwards through history to try to find
             # where the file copy came from if the source of a copy was not in
             # the parent directory. However, this doesn't actually make sense to
             # do (what does a copy from something not in your working copy even
             # mean?) and it causes bugs (eg, issue4476). Instead, we will warn
             # the user that copy information was dropped, so if they didn't
             # expect this outcome it can be fixed, but this is the correct
             # behavior in this circumstance.
 
             if crev:
                 self.ui.debug(" %s: copy %s:%s\n" % (fname, cfname, hex(crev)))
                 meta["copy"] = cfname
                 meta["copyrev"] = hex(crev)
                 fparent1, fparent2 = nullid, newfparent
             else:
                 self.ui.warn(_("warning: can't find ancestor for '%s' "
                                "copied from '%s'!\n") % (fname, cfname))
 
         elif fparent1 == nullid:
             fparent1, fparent2 = fparent2, nullid
         elif fparent2 != nullid:
             # is one parent an ancestor of the other?
             fparentancestors = flog.commonancestorsheads(fparent1, fparent2)
             if fparent1 in fparentancestors:
                 fparent1, fparent2 = fparent2, nullid
             elif fparent2 in fparentancestors:
                 fparent2 = nullid
 
         # is the file changed?
         text = fctx.data()
         if fparent2 != nullid or flog.cmp(fparent1, text) or meta:
             changelist.append(fname)
             return flog.add(text, meta, tr, linkrev, fparent1, fparent2)
         # are just the flags changed during merge?
         elif fname in manifest1 and manifest1.flags(fname) != fctx.flags():
             changelist.append(fname)
 
         return fparent1
 
     def checkcommitpatterns(self, wctx, vdirs, match, status, fail):
         """check for commit arguments that aren't committable"""
         if match.isexact() or match.prefix():
             matched = set(status.modified + status.added + status.removed)
 
             for f in match.files():
                 f = self.dirstate.normalize(f)
                 if f == '.' or f in matched or f in wctx.substate:
                     continue
                 if f in status.deleted:
                     fail(f, _('file not found!'))
                 if f in vdirs: # visited directory
                     d = f + '/'
                     for mf in matched:
                         if mf.startswith(d):
                             break
                     else:
                         fail(f, _("no match under directory!"))
                 elif f not in self.dirstate:
                     fail(f, _("file not tracked!"))
 
     @unfilteredmethod
     def commit(self, text="", user=None, date=None, match=None, force=False,
                editor=False, extra=None):
         """Add a new revision to current repository.
 
         Revision information is gathered from the working directory,
         match can be used to filter the committed files. If editor is
         supplied, it is called to get a commit message.
         """
         if extra is None:
             extra = {}
 
         def fail(f, msg):
             raise error.Abort('%s: %s' % (f, msg))
 
         if not match:
             match = matchmod.always(self.root, '')
 
         if not force:
             vdirs = []
             match.explicitdir = vdirs.append
             match.bad = fail
 
         wlock = lock = tr = None
         try:
             wlock = self.wlock()
             lock = self.lock() # for recent changelog (see issue4368)
 
             wctx = self[None]
             merge = len(wctx.parents()) > 1
 
             if not force and merge and match.ispartial():
                 raise error.Abort(_('cannot partially commit a merge '
                                    '(do not specify files or patterns)'))
 
             status = self.status(match=match, clean=force)
             if force:
                 status.modified.extend(status.clean) # mq may commit clean files
 
             # check subrepos
             subs = []
             commitsubs = set()
             newstate = wctx.substate.copy()
             # only manage subrepos and .hgsubstate if .hgsub is present
             if '.hgsub' in wctx:
                 # we'll decide whether to track this ourselves, thanks
                 for c in status.modified, status.added, status.removed:
                     if '.hgsubstate' in c:
                         c.remove('.hgsubstate')
 
                 # compare current state to last committed state
                 # build new substate based on last committed state
                 oldstate = wctx.p1().substate
                 for s in sorted(newstate.keys()):
                     if not match(s):
                         # ignore working copy, use old state if present
                         if s in oldstate:
                             newstate[s] = oldstate[s]
                             continue
                         if not force:
                             raise error.Abort(
                                 _("commit with new subrepo %s excluded") % s)
                     dirtyreason = wctx.sub(s).dirtyreason(True)
                     if dirtyreason:
                         if not self.ui.configbool('ui', 'commitsubrepos'):
                             raise error.Abort(dirtyreason,
                                 hint=_("use --subrepos for recursive commit"))
                         subs.append(s)
                         commitsubs.add(s)
                     else:
                         bs = wctx.sub(s).basestate()
                         newstate[s] = (newstate[s][0], bs, newstate[s][2])
                         if oldstate.get(s, (None, None, None))[1] != bs:
                             subs.append(s)
 
                 # check for removed subrepos
                 for p in wctx.parents():
                     r = [s for s in p.substate if s not in newstate]
                     subs += [s for s in r if match(s)]
                 if subs:
                     if (not match('.hgsub') and
                         '.hgsub' in (wctx.modified() + wctx.added())):
                         raise error.Abort(
                             _("can't commit subrepos without .hgsub"))
                     status.modified.insert(0, '.hgsubstate')
 
             elif '.hgsub' in status.removed:
                 # clean up .hgsubstate when .hgsub is removed
                 if ('.hgsubstate' in wctx and
                     '.hgsubstate' not in (status.modified + status.added +
                                           status.removed)):
                     status.removed.insert(0, '.hgsubstate')
 
             # make sure all explicit patterns are matched
             if not force:
                 self.checkcommitpatterns(wctx, vdirs, match, status, fail)
 
             cctx = context.workingcommitctx(self, status,
                                             text, user, date, extra)
 
             # internal config: ui.allowemptycommit
             allowemptycommit = (wctx.branch() != wctx.p1().branch()
                                 or extra.get('close') or merge or cctx.files()
                                 or self.ui.configbool('ui', 'allowemptycommit'))
             if not allowemptycommit:
                 return None
 
             if merge and cctx.deleted():
                 raise error.Abort(_("cannot commit merge with missing files"))
 
             ms = mergemod.mergestate.read(self)
             mergeutil.checkunresolved(ms)
 
             if editor:
                 cctx._text = editor(self, cctx, subs)
             edited = (text != cctx._text)
 
             # Save commit message in case this transaction gets rolled back
             # (e.g. by a pretxncommit hook).  Leave the content alone on
             # the assumption that the user will use the same editor again.
             msgfn = self.savecommitmessage(cctx._text)
 
             # commit subs and write new state
             if subs:
                 for s in sorted(commitsubs):
                     sub = wctx.sub(s)
                     self.ui.status(_('committing subrepository %s\n') %
                         subrepo.subrelpath(sub))
                     sr = sub.commit(cctx._text, user, date)
                     newstate[s] = (newstate[s][0], sr)
                 subrepo.writestate(self, newstate)
 
             p1, p2 = self.dirstate.parents()
             hookp1, hookp2 = hex(p1), (p2 != nullid and hex(p2) or '')
             try:
                 self.hook("precommit", throw=True, parent1=hookp1,
                           parent2=hookp2)
                 tr = self.transaction('commit')
                 ret = self.commitctx(cctx, True)
             except: # re-raises
                 if edited:
                     self.ui.write(
                         _('note: commit message saved in %s\n') % msgfn)
                 raise
             # update bookmarks, dirstate and mergestate
             bookmarks.update(self, [p1, p2], ret)
             cctx.markcommitted(ret)
             ms.reset()
             tr.close()
 
         finally:
             lockmod.release(tr, lock, wlock)
 
         def commithook(node=hex(ret), parent1=hookp1, parent2=hookp2):
             # hack for command that use a temporary commit (eg: histedit)
             # temporary commit got stripped before hook release
             if self.changelog.hasnode(ret):
                 self.hook("commit", node=node, parent1=parent1,
                           parent2=parent2)
         self._afterlock(commithook)
         return ret
 
     @unfilteredmethod
     def commitctx(self, ctx, error=False):
         """Add a new revision to current repository.
         Revision information is passed via the context argument.
         """
 
         tr = None
         p1, p2 = ctx.p1(), ctx.p2()
         user = ctx.user()
 
         lock = self.lock()
         try:
             tr = self.transaction("commit")
             trp = weakref.proxy(tr)
 
             if ctx.manifestnode():
                 # reuse an existing manifest revision
                 mn = ctx.manifestnode()
                 files = ctx.files()
             elif ctx.files():
                 m1ctx = p1.manifestctx()
                 m2ctx = p2.manifestctx()
                 mctx = m1ctx.copy()
 
                 m = mctx.read()
                 m1 = m1ctx.read()
                 m2 = m2ctx.read()
 
                 # check in files
                 added = []
                 changed = []
                 removed = list(ctx.removed())
                 linkrev = len(self)
                 self.ui.note(_("committing files:\n"))
                 for f in sorted(ctx.modified() + ctx.added()):
                     self.ui.note(f + "\n")
                     try:
                         fctx = ctx[f]
                         if fctx is None:
                             removed.append(f)
                         else:
                             added.append(f)
                             m[f] = self._filecommit(fctx, m1, m2, linkrev,
                                                     trp, changed)
                             m.setflag(f, fctx.flags())
                     except OSError as inst:
                         self.ui.warn(_("trouble committing %s!\n") % f)
                         raise
                     except IOError as inst:
                         errcode = getattr(inst, 'errno', errno.ENOENT)
                         if error or errcode and errcode != errno.ENOENT:
                             self.ui.warn(_("trouble committing %s!\n") % f)
                         raise
 
                 # update manifest
                 self.ui.note(_("committing manifest\n"))
                 removed = [f for f in sorted(removed) if f in m1 or f in m2]
                 drop = [f for f in removed if f in m]
                 for f in drop:
                     del m[f]
                 mn = mctx.write(trp, linkrev,
                                 p1.manifestnode(), p2.manifestnode(),
                                 added, drop)
                 files = changed + removed
             else:
                 mn = p1.manifestnode()
                 files = []
 
             # update changelog
             self.ui.note(_("committing changelog\n"))
             self.changelog.delayupdate(tr)
             n = self.changelog.add(mn, files, ctx.description(),
                                    trp, p1.node(), p2.node(),
                                    user, ctx.date(), ctx.extra().copy())
             xp1, xp2 = p1.hex(), p2 and p2.hex() or ''
             self.hook('pretxncommit', throw=True, node=hex(n), parent1=xp1,
                       parent2=xp2)
             # set the new commit is proper phase
             targetphase = subrepo.newcommitphase(self.ui, ctx)
             if targetphase:
                 # retract boundary do not alter parent changeset.
                 # if a parent have higher the resulting phase will
                 # be compliant anyway
                 #
                 # if minimal phase was 0 we don't need to retract anything
                 phases.retractboundary(self, tr, targetphase, [n])
             tr.close()
             branchmap.updatecache(self.filtered('served'))
             return n
         finally:
             if tr:
                 tr.release()
             lock.release()
 
     @unfilteredmethod
     def destroying(self):
         '''Inform the repository that nodes are about to be destroyed.
         Intended for use by strip and rollback, so there's a common
         place for anything that has to be done before destroying history.
 
         This is mostly useful for saving state that is in memory and waiting
         to be flushed when the current lock is released. Because a call to
         destroyed is imminent, the repo will be invalidated causing those
         changes to stay in memory (waiting for the next unlock), or vanish
         completely.
         '''
         # When using the same lock to commit and strip, the phasecache is left
         # dirty after committing. Then when we strip, the repo is invalidated,
         # causing those changes to disappear.
         if '_phasecache' in vars(self):
             self._phasecache.write()
 
     @unfilteredmethod
     def destroyed(self):
         '''Inform the repository that nodes have been destroyed.
         Intended for use by strip and rollback, so there's a common
         place for anything that has to be done after destroying history.
         '''
         # When one tries to:
         # 1) destroy nodes thus calling this method (e.g. strip)
         # 2) use phasecache somewhere (e.g. commit)
         #
         # then 2) will fail because the phasecache contains nodes that were
         # removed. We can either remove phasecache from the filecache,
         # causing it to reload next time it is accessed, or simply filter
         # the removed nodes now and write the updated cache.
         self._phasecache.filterunknown(self)
         self._phasecache.write()
 
         # update the 'served' branch cache to help read only server process
         # Thanks to branchcache collaboration this is done from the nearest
         # filtered subset and it is expected to be fast.
         branchmap.updatecache(self.filtered('served'))
 
         # Ensure the persistent tag cache is updated.  Doing it now
         # means that the tag cache only has to worry about destroyed
         # heads immediately after a strip/rollback.  That in turn
         # guarantees that "cachetip == currenttip" (comparing both rev
         # and node) always means no nodes have been added or destroyed.
 
         # XXX this is suboptimal when qrefresh'ing: we strip the current
         # head, refresh the tag cache, then immediately add a new head.
         # But I think doing it this way is necessary for the "instant
         # tag cache retrieval" case to work.
         self.invalidate()
 
     def walk(self, match, node=None):
         '''
         walk recursively through the directory tree or a given
         changeset, finding all files matched by the match
         function
         '''
         return self[node].walk(match)
 
     def status(self, node1='.', node2=None, match=None,
                ignored=False, clean=False, unknown=False,
                listsubrepos=False):
         '''a convenience method that calls node1.status(node2)'''
         return self[node1].status(node2, match, ignored, clean, unknown,
                                   listsubrepos)
 
     def heads(self, start=None):
         if start is None:
             cl = self.changelog
             headrevs = reversed(cl.headrevs())
             return [cl.node(rev) for rev in headrevs]
 
         heads = self.changelog.heads(start)
         # sort the output in rev descending order
         return sorted(heads, key=self.changelog.rev, reverse=True)
 
     def branchheads(self, branch=None, start=None, closed=False):
         '''return a (possibly filtered) list of heads for the given branch
 
         Heads are returned in topological order, from newest to oldest.
         If branch is None, use the dirstate branch.
         If start is not None, return only heads reachable from start.
         If closed is True, return heads that are marked as closed as well.
         '''
         if branch is None:
             branch = self[None].branch()
         branches = self.branchmap()
         if branch not in branches:
             return []
         # the cache returns heads ordered lowest to highest
         bheads = list(reversed(branches.branchheads(branch, closed=closed)))
         if start is not None:
             # filter out the heads that cannot be reached from startrev
             fbheads = set(self.changelog.nodesbetween([start], bheads)[2])
             bheads = [h for h in bheads if h in fbheads]
         return bheads
 
     def branches(self, nodes):
         if not nodes:
             nodes = [self.changelog.tip()]
         b = []
         for n in nodes:
             t = n
             while True:
                 p = self.changelog.parents(n)
                 if p[1] != nullid or p[0] == nullid:
                     b.append((t, n, p[0], p[1]))
                     break
                 n = p[0]
         return b
 
     def between(self, pairs):
         r = []
 
         for top, bottom in pairs:
             n, l, i = top, [], 0
             f = 1
 
             while n != bottom and n != nullid:
                 p = self.changelog.parents(n)[0]
                 if i == f:
                     l.append(n)
                     f = f * 2
                 n = p
                 i += 1
 
             r.append(l)
 
         return r
 
     def checkpush(self, pushop):
         """Extensions can override this function if additional checks have
         to be performed before pushing, or call it if they override push
         command.
         """
         pass
 
     @unfilteredpropertycache
     def prepushoutgoinghooks(self):
         """Return util.hooks consists of a pushop with repo, remote, outgoing
         methods, which are called before pushing changesets.
         """
         return util.hooks()
 
     def pushkey(self, namespace, key, old, new):
         try:
             tr = self.currenttransaction()
             hookargs = {}
             if tr is not None:
                 hookargs.update(tr.hookargs)
             hookargs['namespace'] = namespace
             hookargs['key'] = key
             hookargs['old'] = old
             hookargs['new'] = new
             self.hook('prepushkey', throw=True, **hookargs)
         except error.HookAbort as exc:
             self.ui.write_err(_("pushkey-abort: %s\n") % exc)
             if exc.hint:
                 self.ui.write_err(_("(%s)\n") % exc.hint)
             return False
         self.ui.debug('pushing key for "%s:%s"\n' % (namespace, key))
         ret = pushkey.push(self, namespace, key, old, new)
         def runhook():
             self.hook('pushkey', namespace=namespace, key=key, old=old, new=new,
                       ret=ret)
         self._afterlock(runhook)
         return ret
 
     def listkeys(self, namespace):
         self.hook('prelistkeys', throw=True, namespace=namespace)
         self.ui.debug('listing keys for "%s"\n' % namespace)
         values = pushkey.list(self, namespace)
         self.hook('listkeys', namespace=namespace, values=values)
         return values
 
     def debugwireargs(self, one, two, three=None, four=None, five=None):
         '''used to test argument passing over the wire'''
         return "%s %s %s %s %s" % (one, two, three, four, five)
 
     def savecommitmessage(self, text):
         fp = self.vfs('last-message.txt', 'wb')
         try:
             fp.write(text)
         finally:
             fp.close()
         return self.pathto(fp.name[len(self.root) + 1:])
 
 # used to avoid circular references so destructors work
 def aftertrans(files):
     renamefiles = [tuple(t) for t in files]
     def a():
         for vfs, src, dest in renamefiles:
             # if src and dest refer to a same file, vfs.rename is a no-op,
             # leaving both src and dest on disk. delete dest to make sure
             # the rename couldn't be such a no-op.
             vfs.tryunlink(dest)
             try:
                 vfs.rename(src, dest)
             except OSError: # journal file does not yet exist
                 pass
     return a
 
 def undoname(fn):
     base, name = os.path.split(fn)
     assert name.startswith('journal')
     return os.path.join(base, name.replace('journal', 'undo', 1))
 
 def instance(ui, path, create):
     return localrepository(ui, util.urllocalpath(path), create)
 
 def islocal(path):
     return True
 
 def newreporequirements(repo):
     """Determine the set of requirements for a new local repository.
 
     Extensions can wrap this function to specify custom requirements for
     new repositories.
     """
     ui = repo.ui
     requirements = set(['revlogv1'])
     if ui.configbool('format', 'usestore', True):
         requirements.add('store')
         if ui.configbool('format', 'usefncache', True):
             requirements.add('fncache')
             if ui.configbool('format', 'dotencode', True):
                 requirements.add('dotencode')
 
     compengine = ui.config('experimental', 'format.compression', 'zlib')
     if compengine not in util.compengines:
         raise error.Abort(_('compression engine %s defined by '
                             'experimental.format.compression not available') %
                           compengine,
                           hint=_('run "hg debuginstall" to list available '
                                  'compression engines'))
 
     # zlib is the historical default and doesn't need an explicit requirement.
     if compengine != 'zlib':
         requirements.add('exp-compression-%s' % compengine)
 
     if scmutil.gdinitconfig(ui):
         requirements.add('generaldelta')
     if ui.configbool('experimental', 'treemanifest', False):
         requirements.add('treemanifest')
     if ui.configbool('experimental', 'manifestv2', False):
         requirements.add('manifestv2')
 
     return requirements

tests/test-tag.t

@@ -1,646 +1,696 b''
+  $ cat >> $HGRCPATH << EOF
+  > [experimental]
+  > hook-track-tags=1
+  > [hooks]
+  > txnclose.track-tag=${TESTTMP}/taghook.sh
+  > EOF
+
+  $ cat << EOF > taghook.sh
+  > #!/bin/sh
+  > # escape the "$" otherwise the test runner interpret it when writting the
+  > # file...
+  > if [ -n "\$HG_TAG_MOVED" ]; then
+  >     echo 'hook: tag changes detected'
+  > fi
+  > EOF
+  $ chmod +x taghook.sh
   $ hg init test
   $ cd test
 
   $ echo a > a
   $ hg add a
   $ hg commit -m "test"
   $ hg history
   changeset:   0:acb14030fe0a
   tag:         tip
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     test
   
 
   $ hg tag ' '
   abort: tag names cannot consist entirely of whitespace
   [255]
 
 (this tests also that editor is not invoked, if '--edit' is not
 specified)
 
   $ HGEDITOR=cat hg tag "bleah"
+  hook: tag changes detected
   $ hg history
   changeset:   1:d4f0d2909abc
   tag:         tip
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     Added tag bleah for changeset acb14030fe0a
   
   changeset:   0:acb14030fe0a
   tag:         bleah
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     test
   
 
   $ echo foo >> .hgtags
   $ hg tag "bleah2"
   abort: working copy of .hgtags is changed
   (please commit .hgtags manually)
   [255]
 
   $ hg revert .hgtags
   $ hg tag -r 0 x y z y y z
   abort: tag names must be unique
   [255]
   $ hg tag tap nada dot tip
   abort: the name 'tip' is reserved
   [255]
   $ hg tag .
   abort: the name '.' is reserved
   [255]
   $ hg tag null
   abort: the name 'null' is reserved
   [255]
   $ hg tag "bleah"
   abort: tag 'bleah' already exists (use -f to force)
   [255]
   $ hg tag "blecch" "bleah"
   abort: tag 'bleah' already exists (use -f to force)
   [255]
 
   $ hg tag --remove "blecch"
   abort: tag 'blecch' does not exist
   [255]
   $ hg tag --remove "bleah" "blecch" "blough"
   abort: tag 'blecch' does not exist
   [255]
 
   $ hg tag -r 0 "bleah0"
+  hook: tag changes detected
   $ hg tag -l -r 1 "bleah1"
   $ hg tag gack gawk gorp
+  hook: tag changes detected
   $ hg tag -f gack
+  hook: tag changes detected
   $ hg tag --remove gack gorp
+  hook: tag changes detected
 
   $ hg tag "bleah "
   abort: tag 'bleah' already exists (use -f to force)
   [255]
   $ hg tag " bleah"
   abort: tag 'bleah' already exists (use -f to force)
   [255]
   $ hg tag " bleah"
   abort: tag 'bleah' already exists (use -f to force)
   [255]
   $ hg tag -r 0 "  bleahbleah  "
+  hook: tag changes detected
   $ hg tag -r 0 " bleah bleah "
+  hook: tag changes detected
 
   $ cat .hgtags
   acb14030fe0a21b60322c440ad2d20cf7685a376 bleah
   acb14030fe0a21b60322c440ad2d20cf7685a376 bleah0
   336fccc858a4eb69609a291105009e484a6b6b8d gack
   336fccc858a4eb69609a291105009e484a6b6b8d gawk
   336fccc858a4eb69609a291105009e484a6b6b8d gorp
   336fccc858a4eb69609a291105009e484a6b6b8d gack
   799667b6f2d9b957f73fa644a918c2df22bab58f gack
   799667b6f2d9b957f73fa644a918c2df22bab58f gack
   0000000000000000000000000000000000000000 gack
   336fccc858a4eb69609a291105009e484a6b6b8d gorp
   0000000000000000000000000000000000000000 gorp
   acb14030fe0a21b60322c440ad2d20cf7685a376 bleahbleah
   acb14030fe0a21b60322c440ad2d20cf7685a376 bleah bleah
 
   $ cat .hg/localtags
   d4f0d2909abc9290e2773c08837d70c1794e3f5a bleah1
 
 tagging on a non-head revision
 
   $ hg update 0
   0 files updated, 0 files merged, 1 files removed, 0 files unresolved
   $ hg tag -l localblah
   $ hg tag "foobar"
   abort: working directory is not at a branch head (use -f to force)
   [255]
   $ hg tag -f "foobar"
+  hook: tag changes detected
   $ cat .hgtags
   acb14030fe0a21b60322c440ad2d20cf7685a376 foobar
   $ cat .hg/localtags
   d4f0d2909abc9290e2773c08837d70c1794e3f5a bleah1
   acb14030fe0a21b60322c440ad2d20cf7685a376 localblah
 
   $ hg tag -l 'xx
   > newline'
   abort: '\n' cannot be used in a name
   [255]
   $ hg tag -l 'xx:xx'
   abort: ':' cannot be used in a name
   [255]
 
 cloning local tags
 
   $ cd ..
   $ hg -R test log -r0:5
   changeset:   0:acb14030fe0a
   tag:         bleah
   tag:         bleah bleah
   tag:         bleah0
   tag:         bleahbleah
   tag:         foobar
   tag:         localblah
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     test
   
   changeset:   1:d4f0d2909abc
   tag:         bleah1
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     Added tag bleah for changeset acb14030fe0a
   
   changeset:   2:336fccc858a4
   tag:         gawk
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     Added tag bleah0 for changeset acb14030fe0a
   
   changeset:   3:799667b6f2d9
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     Added tag gack, gawk, gorp for changeset 336fccc858a4
   
   changeset:   4:154eeb7c0138
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     Added tag gack for changeset 799667b6f2d9
   
   changeset:   5:b4bb47aaff09
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     Removed tag gack, gorp
   
   $ hg clone -q -rbleah1 test test1
+  hook: tag changes detected
   $ hg -R test1 parents --style=compact
   1[tip]   d4f0d2909abc   1970-01-01 00:00 +0000   test
     Added tag bleah for changeset acb14030fe0a
   
   $ hg clone -q -r5 test#bleah1 test2
+  hook: tag changes detected
   $ hg -R test2 parents --style=compact
   5[tip]   b4bb47aaff09   1970-01-01 00:00 +0000   test
     Removed tag gack, gorp
   
   $ hg clone -q -U test#bleah1 test3
+  hook: tag changes detected
   $ hg -R test3 parents --style=compact
 
   $ cd test
 
 Issue601: hg tag doesn't do the right thing if .hgtags or localtags
 doesn't end with EOL
 
   $ python << EOF
   > f = file('.hg/localtags'); last = f.readlines()[-1][:-1]; f.close()
   > f = file('.hg/localtags', 'w'); f.write(last); f.close()
   > EOF
   $ cat .hg/localtags; echo
   acb14030fe0a21b60322c440ad2d20cf7685a376 localblah
   $ hg tag -l localnewline
   $ cat .hg/localtags; echo
   acb14030fe0a21b60322c440ad2d20cf7685a376 localblah
   c2899151f4e76890c602a2597a650a72666681bf localnewline
   
 
   $ python << EOF
   > f = file('.hgtags'); last = f.readlines()[-1][:-1]; f.close()
   > f = file('.hgtags', 'w'); f.write(last); f.close()
   > EOF
   $ hg ci -m'broken manual edit of .hgtags'
+  hook: tag changes detected
   $ cat .hgtags; echo
   acb14030fe0a21b60322c440ad2d20cf7685a376 foobar
   $ hg tag newline
+  hook: tag changes detected
   $ cat .hgtags; echo
   acb14030fe0a21b60322c440ad2d20cf7685a376 foobar
   a0eea09de1eeec777b46f2085260a373b2fbc293 newline
   
 
 tag and branch using same name
 
   $ hg branch tag-and-branch-same-name
   marked working directory as branch tag-and-branch-same-name
   (branches are permanent and global, did you want a bookmark?)
   $ hg ci -m"discouraged"
   $ hg tag tag-and-branch-same-name
   warning: tag tag-and-branch-same-name conflicts with existing branch name
+  hook: tag changes detected
 
 test custom commit messages
 
   $ cat > editor.sh << '__EOF__'
   > echo "==== before editing"
   > cat "$1"
   > echo "===="
   > echo "custom tag message" > "$1"
   > echo "second line" >> "$1"
   > __EOF__
 
 at first, test saving last-message.txt
 
 (test that editor is not invoked before transaction starting)
 
   $ cat > .hg/hgrc << '__EOF__'
   > [hooks]
   > # this failure occurs before editor invocation
   > pretag.test-saving-lastmessage = false
   > __EOF__
   $ rm -f .hg/last-message.txt
   $ HGEDITOR="\"sh\" \"`pwd`/editor.sh\"" hg tag custom-tag -e
   abort: pretag.test-saving-lastmessage hook exited with status 1
   [255]
   $ test -f .hg/last-message.txt
   [1]
 
 (test that editor is invoked and commit message is saved into
 "last-message.txt")
 
   $ cat >> .hg/hgrc << '__EOF__'
   > [hooks]
   > pretag.test-saving-lastmessage =
   > # this failure occurs after editor invocation
   > pretxncommit.unexpectedabort = false
   > __EOF__
 
 (this tests also that editor is invoked, if '--edit' is specified,
 regardless of '--message')
 
   $ rm -f .hg/last-message.txt
   $ HGEDITOR="\"sh\" \"`pwd`/editor.sh\"" hg tag custom-tag -e -m "foo bar"
   ==== before editing
   foo bar
   
   
   HG: Enter commit message.  Lines beginning with 'HG:' are removed.
   HG: Leave message empty to abort commit.
   HG: --
   HG: user: test
   HG: branch 'tag-and-branch-same-name'
   HG: changed .hgtags
   ====
   note: commit message saved in .hg/last-message.txt
   transaction abort!
   rollback completed
   abort: pretxncommit.unexpectedabort hook exited with status 1
   [255]
   $ cat .hg/last-message.txt
   custom tag message
   second line
 
   $ cat >> .hg/hgrc << '__EOF__'
   > [hooks]
   > pretxncommit.unexpectedabort =
   > __EOF__
   $ hg status .hgtags
   M .hgtags
   $ hg revert --no-backup -q .hgtags
 
 then, test custom commit message itself
 
   $ HGEDITOR="\"sh\" \"`pwd`/editor.sh\"" hg tag custom-tag -e
   ==== before editing
   Added tag custom-tag for changeset 75a534207be6
   
   
   HG: Enter commit message.  Lines beginning with 'HG:' are removed.
   HG: Leave message empty to abort commit.
   HG: --
   HG: user: test
   HG: branch 'tag-and-branch-same-name'
   HG: changed .hgtags
   ====
+  hook: tag changes detected
   $ hg log -l1 --template "{desc}\n"
   custom tag message
   second line
 
 
 local tag with .hgtags modified
 
   $ hg tag hgtags-modified
+  hook: tag changes detected
   $ hg rollback
   repository tip rolled back to revision 13 (undo commit)
   working directory now based on revision 13
   $ hg st
   M .hgtags
   ? .hgtags.orig
   ? editor.sh
   $ hg tag --local baz
   $ hg revert --no-backup .hgtags
 
 
 tagging when at named-branch-head that's not a topo-head
 
   $ hg up default
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ hg merge -t internal:local
   0 files updated, 1 files merged, 0 files removed, 0 files unresolved
   (branch merge, don't forget to commit)
   $ hg ci -m 'merge named branch'
+  hook: tag changes detected
   $ hg up 13
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ hg tag new-topo-head
+  hook: tag changes detected
 
 tagging on null rev
 
   $ hg up null
   0 files updated, 0 files merged, 2 files removed, 0 files unresolved
   $ hg tag nullrev
   abort: working directory is not at a branch head (use -f to force)
   [255]
 
   $ hg init empty
   $ hg tag -R empty nullrev
   abort: cannot tag null revision
   [255]
 
   $ hg tag -R empty -r 00000000000 -f nulltag
   abort: cannot tag null revision
   [255]
 
   $ cd ..
 
 tagging on an uncommitted merge (issue2542)
 
   $ hg init repo-tag-uncommitted-merge
   $ cd repo-tag-uncommitted-merge
   $ echo c1 > f1
   $ hg ci -Am0
   adding f1
   $ echo c2 > f2
   $ hg ci -Am1
   adding f2
   $ hg co -q 0
   $ hg branch b1
   marked working directory as branch b1
   (branches are permanent and global, did you want a bookmark?)
   $ hg ci -m2
   $ hg up default
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ hg merge b1
   0 files updated, 0 files merged, 0 files removed, 0 files unresolved
   (branch merge, don't forget to commit)
 
   $ hg tag t1
   abort: uncommitted merge
   [255]
   $ hg status
   $ hg tag --rev 1 t2
   abort: uncommitted merge
   [255]
   $ hg tag --rev 1 --local t3
   $ hg tags -v
   tip                                2:2a156e8887cc
   t3                                 1:c3adabd1a5f4 local
 
   $ cd ..
 
 commit hook on tag used to be run without write lock - issue3344
 
   $ hg init repo-tag
   $ touch repo-tag/test
   $ hg -R repo-tag commit -A -m "test"
   adding test
   $ hg init repo-tag-target
   $ cat > "$TESTTMP/issue3344.sh" <<EOF
   > hg push "$TESTTMP/repo-tag-target"
   > EOF
   $ hg -R repo-tag --config hooks.commit="sh ../issue3344.sh" tag tag
+  hook: tag changes detected
   pushing to $TESTTMP/repo-tag-target (glob)
   searching for changes
   adding changesets
   adding manifests
   adding file changes
   added 2 changesets with 2 changes to 2 files
+  hook: tag changes detected
 
 automatically merge resolvable tag conflicts (i.e. tags that differ in rank)
 create two clones with some different tags as well as some common tags
 check that we can merge tags that differ in rank
 
   $ hg init repo-automatic-tag-merge
   $ cd repo-automatic-tag-merge
   $ echo c0 > f0
   $ hg ci -A -m0
   adding f0
   $ hg tag tbase
+  hook: tag changes detected
   $ hg up -qr '.^'
   $ hg log -r 'wdir()' -T "{latesttagdistance}\n"
   1
   $ hg up -q
   $ hg log -r 'wdir()' -T "{latesttagdistance}\n"
   2
   $ cd ..
   $ hg clone repo-automatic-tag-merge repo-automatic-tag-merge-clone
   updating to branch default
   2 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ cd repo-automatic-tag-merge-clone
   $ echo c1 > f1
   $ hg ci -A -m1
   adding f1
   $ hg tag t1 t2 t3
+  hook: tag changes detected
   $ hg tag --remove t2
+  hook: tag changes detected
   $ hg tag t5
+  hook: tag changes detected
   $ echo c2 > f2
   $ hg ci -A -m2
   adding f2
   $ hg tag -f t3
+  hook: tag changes detected
 
   $ cd ../repo-automatic-tag-merge
   $ echo c3 > f3
   $ hg ci -A -m3
   adding f3
   $ hg tag -f t4 t5 t6
+  hook: tag changes detected
 
   $ hg up -q '.^'
   $ hg log -r 'wdir()' -T "{changessincelatesttag} changes since {latesttag}\n"
   1 changes since t4:t5:t6
   $ hg log -r '.' -T "{changessincelatesttag} changes since {latesttag}\n"
   0 changes since t4:t5:t6
   $ echo c5 > f3
   $ hg log -r 'wdir()' -T "{changessincelatesttag} changes since {latesttag}\n"
   1 changes since t4:t5:t6
   $ hg up -qC
 
   $ hg tag --remove t5
+  hook: tag changes detected
   $ echo c4 > f4
   $ hg log -r '.' -T "{changessincelatesttag} changes since {latesttag}\n"
   2 changes since t4:t6
   $ hg log -r '.' -T "{latesttag % '{latesttag}\n'}"
   t4
   t6
   $ hg log -r '.' -T "{latesttag('t4') % 'T: {tag}, C: {changes}, D: {distance}\n'}"
   T: t4, C: 2, D: 2
   $ hg log -r '.' -T "{latesttag('re:\d') % 'T: {tag}, C: {changes}, D: {distance}\n'}"
   T: t4, C: 2, D: 2
   T: t6, C: 2, D: 2
   $ hg log -r . -T '{join(latesttag(), "*")}\n'
   t4*t6
   $ hg ci -A -m4
   adding f4
   $ hg log -r 'wdir()' -T "{changessincelatesttag} changes since {latesttag}\n"
   4 changes since t4:t6
   $ hg tag t2
+  hook: tag changes detected
   $ hg tag -f t6
+  hook: tag changes detected
 
   $ cd ../repo-automatic-tag-merge-clone
   $ hg pull
   pulling from $TESTTMP/repo-automatic-tag-merge (glob)
   searching for changes
   adding changesets
   adding manifests
   adding file changes
   added 6 changesets with 6 changes to 3 files (+1 heads)
+  hook: tag changes detected
   (run 'hg heads' to see heads, 'hg merge' to merge)
   $ hg merge --tool internal:tagmerge
   merging .hgtags
   2 files updated, 1 files merged, 0 files removed, 0 files unresolved
   (branch merge, don't forget to commit)
   $ hg status
   M .hgtags
   M f3
   M f4
   $ hg resolve -l
   R .hgtags
   $ cat .hgtags
   9aa4e1292a27a248f8d07339bed9931d54907be7 t4
   9aa4e1292a27a248f8d07339bed9931d54907be7 t6
   9aa4e1292a27a248f8d07339bed9931d54907be7 t6
   09af2ce14077a94effef208b49a718f4836d4338 t6
   6cee5c8f3e5b4ae1a3996d2f6489c3e08eb5aea7 tbase
   4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t1
   929bca7b18d067cbf3844c3896319a940059d748 t2
   4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t2
   4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t3
   4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t2
   0000000000000000000000000000000000000000 t2
   875517b4806a848f942811a315a5bce30804ae85 t5
   9aa4e1292a27a248f8d07339bed9931d54907be7 t5
   9aa4e1292a27a248f8d07339bed9931d54907be7 t5
   0000000000000000000000000000000000000000 t5
   4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t3
   79505d5360b07e3e79d1052e347e73c02b8afa5b t3
 
 check that the merge tried to minimize the diff with the first merge parent
 
   $ hg diff --git -r 'p1()' .hgtags
   diff --git a/.hgtags b/.hgtags
   --- a/.hgtags
   +++ b/.hgtags
   @@ -1,9 +1,17 @@
   +9aa4e1292a27a248f8d07339bed9931d54907be7 t4
   +9aa4e1292a27a248f8d07339bed9931d54907be7 t6
   +9aa4e1292a27a248f8d07339bed9931d54907be7 t6
   +09af2ce14077a94effef208b49a718f4836d4338 t6
    6cee5c8f3e5b4ae1a3996d2f6489c3e08eb5aea7 tbase
    4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t1
   +929bca7b18d067cbf3844c3896319a940059d748 t2
    4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t2
    4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t3
    4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t2
    0000000000000000000000000000000000000000 t2
    875517b4806a848f942811a315a5bce30804ae85 t5
   +9aa4e1292a27a248f8d07339bed9931d54907be7 t5
   +9aa4e1292a27a248f8d07339bed9931d54907be7 t5
   +0000000000000000000000000000000000000000 t5
    4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t3
    79505d5360b07e3e79d1052e347e73c02b8afa5b t3
 
 detect merge tag conflicts
 
   $ hg update -C -r tip
   3 files updated, 0 files merged, 2 files removed, 0 files unresolved
   $ hg tag t7
+  hook: tag changes detected
   $ hg update -C -r 'first(sort(head()))'
   3 files updated, 0 files merged, 2 files removed, 0 files unresolved
   $ printf "%s %s\n" `hg log -r . --template "{node} t7"` >> .hgtags
   $ hg commit -m "manually add conflicting t7 tag"
+  hook: tag changes detected
   $ hg merge --tool internal:tagmerge
   merging .hgtags
   automatic .hgtags merge failed
   the following 1 tags are in conflict: t7
   automatic tag merging of .hgtags failed! (use 'hg resolve --tool :merge' or another merge tool of your choice)
   2 files updated, 0 files merged, 0 files removed, 1 files unresolved
   use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
   [1]
   $ hg resolve -l
   U .hgtags
   $ cat .hgtags
   6cee5c8f3e5b4ae1a3996d2f6489c3e08eb5aea7 tbase
   4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t1
   4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t2
   4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t3
   4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t2
   0000000000000000000000000000000000000000 t2
   875517b4806a848f942811a315a5bce30804ae85 t5
   4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t3
   79505d5360b07e3e79d1052e347e73c02b8afa5b t3
   ea918d56be86a4afc5a95312e8b6750e1428d9d2 t7
 
   $ cd ..
 
 handle the loss of tags
 
   $ hg clone repo-automatic-tag-merge-clone repo-merge-lost-tags
   updating to branch default
   4 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ cd repo-merge-lost-tags
   $ echo c5 > f5
   $ hg ci -A -m5
   adding f5
   $ hg tag -f t7
+  hook: tag changes detected
   $ hg update -r 'p1(t7)'
   1 files updated, 0 files merged, 1 files removed, 0 files unresolved
   $ printf '' > .hgtags
   $ hg commit -m 'delete all tags'
   created new head
+  hook: tag changes detected
   $ hg log -r 'max(t7::)'
   changeset:   17:ffe462b50880
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     Added tag t7 for changeset fd3a9e394ce3
   
   $ hg update -r 'max(t7::)'
   2 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ hg merge -r tip --tool internal:tagmerge
   merging .hgtags
   0 files updated, 1 files merged, 0 files removed, 0 files unresolved
   (branch merge, don't forget to commit)
   $ hg resolve -l
   R .hgtags
   $ cat .hgtags
   6cee5c8f3e5b4ae1a3996d2f6489c3e08eb5aea7 tbase
   0000000000000000000000000000000000000000 tbase
   4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t1
   0000000000000000000000000000000000000000 t1
   4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t2
   4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t3
   4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t2
   0000000000000000000000000000000000000000 t2
   875517b4806a848f942811a315a5bce30804ae85 t5
   0000000000000000000000000000000000000000 t5
   4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t3
   79505d5360b07e3e79d1052e347e73c02b8afa5b t3
   0000000000000000000000000000000000000000 t3
   ea918d56be86a4afc5a95312e8b6750e1428d9d2 t7
   0000000000000000000000000000000000000000 t7
   ea918d56be86a4afc5a95312e8b6750e1428d9d2 t7
   fd3a9e394ce3afb354a496323bf68ac1755a30de t7
 
 also check that we minimize the diff with the 1st merge parent
 
   $ hg diff --git -r 'p1()' .hgtags
   diff --git a/.hgtags b/.hgtags
   --- a/.hgtags
   +++ b/.hgtags
   @@ -1,12 +1,17 @@
    6cee5c8f3e5b4ae1a3996d2f6489c3e08eb5aea7 tbase
   +0000000000000000000000000000000000000000 tbase
    4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t1
   +0000000000000000000000000000000000000000 t1
    4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t2
    4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t3
    4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t2
    0000000000000000000000000000000000000000 t2
    875517b4806a848f942811a315a5bce30804ae85 t5
   +0000000000000000000000000000000000000000 t5
    4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t3
    79505d5360b07e3e79d1052e347e73c02b8afa5b t3
   +0000000000000000000000000000000000000000 t3
    ea918d56be86a4afc5a95312e8b6750e1428d9d2 t7
   +0000000000000000000000000000000000000000 t7
    ea918d56be86a4afc5a95312e8b6750e1428d9d2 t7
    fd3a9e394ce3afb354a496323bf68ac1755a30de t7