tag: use filtered repo when creating new tags (issue5539)

When pruning a changeset that added a tag and then adding another tag, the
"pruned" tag gets restored. This is because the tag creation step (tags._tag()
call in tags.tag()) is currently done on the unfiltered repo. This behavior
has been there from 7977d35df13b which backs out b08af8f0ac01 with no clear
reason but caution on unthought situations at that time. In this changeset, we
pass the filtered repo to tags._tag(), preventing "pruned" tags to reappear.
This somehow restores b08af8f0ac01, though now we arguably have a valid use
case for.

mercurial/tags.py

@@ -1,788 +1,788
 # tags.py - read tag info from local repository
 #
 # Copyright 2009 Matt Mackall <[e-mail]>
 # Copyright 2009 Greg Ward <[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.
 
 # Currently this module only deals with reading and caching tags.
 # Eventually, it could take care of updating (adding/removing/moving)
 # tags too.
 
 from __future__ import absolute_import
 
 import errno
 
 from .node import (
     bin,
     hex,
     nullid,
     short,
 )
 from .i18n import _
 from . import (
     encoding,
     error,
     match as matchmod,
     scmutil,
     util,
 )
 
 # Tags computation can be expensive and caches exist to make it fast in
 # the common case.
 #
 # The "hgtagsfnodes1" cache file caches the .hgtags filenode values for
 # each revision in the repository. The file is effectively an array of
 # fixed length records. Read the docs for "hgtagsfnodescache" for technical
 # details.
 #
 # The .hgtags filenode cache grows in proportion to the length of the
 # changelog. The file is truncated when the # changelog is stripped.
 #
 # The purpose of the filenode cache is to avoid the most expensive part
 # of finding global tags, which is looking up the .hgtags filenode in the
 # manifest for each head. This can take dozens or over 100ms for
 # repositories with very large manifests. Multiplied by dozens or even
 # hundreds of heads and there is a significant performance concern.
 #
 # There also exist a separate cache file for each repository filter.
 # These "tags-*" files store information about the history of tags.
 #
 # The tags cache files consists of a cache validation line followed by
 # a history of tags.
 #
 # The cache validation line has the format:
 #
 #   <tiprev> <tipnode> [<filteredhash>]
 #
 # <tiprev> is an integer revision and <tipnode> is a 40 character hex
 # node for that changeset. These redundantly identify the repository
 # tip from the time the cache was written. In addition, <filteredhash>,
 # if present, is a 40 character hex hash of the contents of the filtered
 # revisions for this filter. If the set of filtered revs changes, the
 # hash will change and invalidate the cache.
 #
 # The history part of the tags cache consists of lines of the form:
 #
 #   <node> <tag>
 #
 # (This format is identical to that of .hgtags files.)
 #
 # <tag> is the tag name and <node> is the 40 character hex changeset
 # the tag is associated with.
 #
 # Tags are written sorted by tag name.
 #
 # Tags associated with multiple changesets have an entry for each changeset.
 # The most recent changeset (in terms of revlog ordering for the head
 # setting it) for each tag is last.
 
 def fnoderevs(ui, repo, revs):
     """return the list of '.hgtags' fnodes used in a set revisions
 
     This is returned as list of unique fnodes. We use a list instead of a set
     because order matters when it comes to tags."""
     unfi = repo.unfiltered()
     tonode = unfi.changelog.node
     nodes = [tonode(r) for r in revs]
     fnodes = _getfnodes(ui, repo, nodes[::-1]) # reversed help the cache
     fnodes = _filterfnodes(fnodes, nodes)
     return fnodes
 
 def _nulltonone(value):
     """convert nullid to None
 
     For tag value, nullid means "deleted". This small utility function helps
     translating that to None."""
     if value == nullid:
         return None
     return value
 
 def difftags(ui, repo, oldfnodes, newfnodes):
     """list differences between tags expressed in two set of file-nodes
 
     The list contains entries in the form: (tagname, oldvalue, new value).
     None is used to expressed missing value:
         ('foo', None, 'abcd') is a new tag,
         ('bar', 'ef01', None) is a deletion,
         ('baz', 'abcd', 'ef01') is a tag movement.
     """
     if oldfnodes == newfnodes:
         return []
     oldtags = _tagsfromfnodes(ui, repo, oldfnodes)
     newtags = _tagsfromfnodes(ui, repo, newfnodes)
 
     # list of (tag, old, new): None means missing
     entries = []
     for tag, (new, __) in newtags.items():
         new = _nulltonone(new)
         old, __ = oldtags.pop(tag, (None, None))
         old = _nulltonone(old)
         if old != new:
             entries.append((tag, old, new))
     # handle deleted tags
     for tag, (old, __) in oldtags.items():
         old = _nulltonone(old)
         if old is not None:
             entries.append((tag, old, None))
     entries.sort()
     return entries
 
 def writediff(fp, difflist):
     """write tags diff information to a file.
 
     Data are stored with a line based format:
 
         <action> <hex-node> <tag-name>\n
 
     Action are defined as follow:
        -R tag is removed,
        +A tag is added,
        -M tag is moved (old value),
        +M tag is moved (new value),
 
     Example:
 
          +A 875517b4806a848f942811a315a5bce30804ae85 t5
 
     See documentation of difftags output for details about the input.
     """
     add = '+A %s %s\n'
     remove = '-R %s %s\n'
     updateold = '-M %s %s\n'
     updatenew = '+M %s %s\n'
     for tag, old, new in difflist:
         # translate to hex
         if old is not None:
             old = hex(old)
         if new is not None:
             new = hex(new)
         # write to file
         if old is None:
             fp.write(add % (new, tag))
         elif new is None:
             fp.write(remove % (old, tag))
         else:
             fp.write(updateold % (old, tag))
             fp.write(updatenew % (new, tag))
 
 def findglobaltags(ui, repo):
     '''Find global tags in a repo: return a tagsmap
 
     tagsmap: tag name to (node, hist) 2-tuples.
 
     The tags cache is read and updated as a side-effect of calling.
     '''
     (heads, tagfnode, valid, cachetags, shouldwrite) = _readtagcache(ui, repo)
     if cachetags is not None:
         assert not shouldwrite
         # XXX is this really 100% correct?  are there oddball special
         # cases where a global tag should outrank a local tag but won't,
         # because cachetags does not contain rank info?
         alltags = {}
         _updatetags(cachetags, alltags)
         return alltags
 
     for head in reversed(heads):  # oldest to newest
         assert head in repo.changelog.nodemap, \
                "tag cache returned bogus head %s" % short(head)
     fnodes = _filterfnodes(tagfnode, reversed(heads))
     alltags = _tagsfromfnodes(ui, repo, fnodes)
 
     # and update the cache (if necessary)
     if shouldwrite:
         _writetagcache(ui, repo, valid, alltags)
     return alltags
 
 def _filterfnodes(tagfnode, nodes):
     """return a list of unique fnodes
 
     The order of this list matches the order of "nodes". Preserving this order
     is important as reading tags in different order provides different
     results."""
     seen = set()  # set of fnode
     fnodes = []
     for no in nodes:  # oldest to newest
         fnode = tagfnode.get(no)
         if fnode and fnode not in seen:
             seen.add(fnode)
             fnodes.append(fnode)
     return fnodes
 
 def _tagsfromfnodes(ui, repo, fnodes):
     """return a tagsmap from a list of file-node
 
     tagsmap: tag name to (node, hist) 2-tuples.
 
     The order of the list matters."""
     alltags = {}
     fctx = None
     for fnode in fnodes:
         if fctx is None:
             fctx = repo.filectx('.hgtags', fileid=fnode)
         else:
             fctx = fctx.filectx(fnode)
         filetags = _readtags(ui, repo, fctx.data().splitlines(), fctx)
         _updatetags(filetags, alltags)
     return alltags
 
 def readlocaltags(ui, repo, alltags, tagtypes):
     '''Read local tags in repo. Update alltags and tagtypes.'''
     try:
         data = repo.vfs.read("localtags")
     except IOError as inst:
         if inst.errno != errno.ENOENT:
             raise
         return
 
     # localtags is in the local encoding; re-encode to UTF-8 on
     # input for consistency with the rest of this module.
     filetags = _readtags(
         ui, repo, data.splitlines(), "localtags",
         recode=encoding.fromlocal)
 
     # remove tags pointing to invalid nodes
     cl = repo.changelog
     for t in filetags.keys():
         try:
             cl.rev(filetags[t][0])
         except (LookupError, ValueError):
             del filetags[t]
 
     _updatetags(filetags, alltags, 'local', tagtypes)
 
 def _readtaghist(ui, repo, lines, fn, recode=None, calcnodelines=False):
     '''Read tag definitions from a file (or any source of lines).
 
     This function returns two sortdicts with similar information:
 
     - the first dict, bintaghist, contains the tag information as expected by
       the _readtags function, i.e. a mapping from tag name to (node, hist):
         - node is the node id from the last line read for that name,
         - hist is the list of node ids previously associated with it (in file
           order). All node ids are binary, not hex.
 
     - the second dict, hextaglines, is a mapping from tag name to a list of
       [hexnode, line number] pairs, ordered from the oldest to the newest node.
 
     When calcnodelines is False the hextaglines dict is not calculated (an
     empty dict is returned). This is done to improve this function's
     performance in cases where the line numbers are not needed.
     '''
 
     bintaghist = util.sortdict()
     hextaglines = util.sortdict()
     count = 0
 
     def dbg(msg):
         ui.debug("%s, line %s: %s\n" % (fn, count, msg))
 
     for nline, line in enumerate(lines):
         count += 1
         if not line:
             continue
         try:
             (nodehex, name) = line.split(" ", 1)
         except ValueError:
             dbg("cannot parse entry")
             continue
         name = name.strip()
         if recode:
             name = recode(name)
         try:
             nodebin = bin(nodehex)
         except TypeError:
             dbg("node '%s' is not well formed" % nodehex)
             continue
 
         # update filetags
         if calcnodelines:
             # map tag name to a list of line numbers
             if name not in hextaglines:
                 hextaglines[name] = []
             hextaglines[name].append([nodehex, nline])
             continue
         # map tag name to (node, hist)
         if name not in bintaghist:
             bintaghist[name] = []
         bintaghist[name].append(nodebin)
     return bintaghist, hextaglines
 
 def _readtags(ui, repo, lines, fn, recode=None, calcnodelines=False):
     '''Read tag definitions from a file (or any source of lines).
 
     Returns a mapping from tag name to (node, hist).
 
     "node" is the node id from the last line read for that name. "hist"
     is the list of node ids previously associated with it (in file order).
     All node ids are binary, not hex.
     '''
     filetags, nodelines = _readtaghist(ui, repo, lines, fn, recode=recode,
                                        calcnodelines=calcnodelines)
     # util.sortdict().__setitem__ is much slower at replacing then inserting
     # new entries. The difference can matter if there are thousands of tags.
     # Create a new sortdict to avoid the performance penalty.
     newtags = util.sortdict()
     for tag, taghist in filetags.items():
         newtags[tag] = (taghist[-1], taghist[:-1])
     return newtags
 
 def _updatetags(filetags, alltags, tagtype=None, tagtypes=None):
     """Incorporate the tag info read from one file into dictionnaries
 
     The first one, 'alltags', is a "tagmaps" (see 'findglobaltags' for details).
 
     The second one, 'tagtypes', is optional and will be updated to track the
     "tagtype" of entries in the tagmaps. When set, the 'tagtype' argument also
     needs to be set."""
     if tagtype is None:
         assert tagtypes is None
 
     for name, nodehist in filetags.iteritems():
         if name not in alltags:
             alltags[name] = nodehist
             if tagtype is not None:
                 tagtypes[name] = tagtype
             continue
 
         # we prefer alltags[name] if:
         #  it supersedes us OR
         #  mutual supersedes and it has a higher rank
         # otherwise we win because we're tip-most
         anode, ahist = nodehist
         bnode, bhist = alltags[name]
         if (bnode != anode and anode in bhist and
             (bnode not in ahist or len(bhist) > len(ahist))):
             anode = bnode
         elif tagtype is not None:
             tagtypes[name] = tagtype
         ahist.extend([n for n in bhist if n not in ahist])
         alltags[name] = anode, ahist
 
 def _filename(repo):
     """name of a tagcache file for a given repo or repoview"""
     filename = 'tags2'
     if repo.filtername:
         filename = '%s-%s' % (filename, repo.filtername)
     return filename
 
 def _readtagcache(ui, repo):
     '''Read the tag cache.
 
     Returns a tuple (heads, fnodes, validinfo, cachetags, shouldwrite).
 
     If the cache is completely up-to-date, "cachetags" is a dict of the
     form returned by _readtags() and "heads", "fnodes", and "validinfo" are
     None and "shouldwrite" is False.
 
     If the cache is not up to date, "cachetags" is None. "heads" is a list
     of all heads currently in the repository, ordered from tip to oldest.
     "validinfo" is a tuple describing cache validation info. This is used
     when writing the tags cache. "fnodes" is a mapping from head to .hgtags
     filenode. "shouldwrite" is True.
 
     If the cache is not up to date, the caller is responsible for reading tag
     info from each returned head. (See findglobaltags().)
     '''
     try:
         cachefile = repo.cachevfs(_filename(repo), 'r')
         # force reading the file for static-http
         cachelines = iter(cachefile)
     except IOError:
         cachefile = None
 
     cacherev = None
     cachenode = None
     cachehash = None
     if cachefile:
         try:
             validline = next(cachelines)
             validline = validline.split()
             cacherev = int(validline[0])
             cachenode = bin(validline[1])
             if len(validline) > 2:
                 cachehash = bin(validline[2])
         except Exception:
             # corruption of the cache, just recompute it.
             pass
 
     tipnode = repo.changelog.tip()
     tiprev = len(repo.changelog) - 1
 
     # Case 1 (common): tip is the same, so nothing has changed.
     # (Unchanged tip trivially means no changesets have been added.
     # But, thanks to localrepository.destroyed(), it also means none
     # have been destroyed by strip or rollback.)
     if (cacherev == tiprev
             and cachenode == tipnode
             and cachehash == scmutil.filteredhash(repo, tiprev)):
         tags = _readtags(ui, repo, cachelines, cachefile.name)
         cachefile.close()
         return (None, None, None, tags, False)
     if cachefile:
         cachefile.close()               # ignore rest of file
 
     valid = (tiprev, tipnode, scmutil.filteredhash(repo, tiprev))
 
     repoheads = repo.heads()
     # Case 2 (uncommon): empty repo; get out quickly and don't bother
     # writing an empty cache.
     if repoheads == [nullid]:
         return ([], {}, valid, {}, False)
 
     # Case 3 (uncommon): cache file missing or empty.
 
     # Case 4 (uncommon): tip rev decreased.  This should only happen
     # when we're called from localrepository.destroyed().  Refresh the
     # cache so future invocations will not see disappeared heads in the
     # cache.
 
     # Case 5 (common): tip has changed, so we've added/replaced heads.
 
     # As it happens, the code to handle cases 3, 4, 5 is the same.
 
     # N.B. in case 4 (nodes destroyed), "new head" really means "newly
     # exposed".
     if not len(repo.file('.hgtags')):
         # No tags have ever been committed, so we can avoid a
         # potentially expensive search.
         return ([], {}, valid, None, True)
 
 
     # Now we have to lookup the .hgtags filenode for every new head.
     # This is the most expensive part of finding tags, so performance
     # depends primarily on the size of newheads.  Worst case: no cache
     # file, so newheads == repoheads.
     cachefnode = _getfnodes(ui, repo, repoheads)
 
     # Caller has to iterate over all heads, but can use the filenodes in
     # cachefnode to get to each .hgtags revision quickly.
     return (repoheads, cachefnode, valid, None, True)
 
 def _getfnodes(ui, repo, nodes):
     """return .hgtags fnodes for a list of changeset nodes
 
     Return value is a {node: fnode} mapping. There will be no entry for nodes
     without a '.hgtags' file.
     """
     starttime = util.timer()
     fnodescache = hgtagsfnodescache(repo.unfiltered())
     cachefnode = {}
     for node in reversed(nodes):
         fnode = fnodescache.getfnode(node)
         if fnode != nullid:
             cachefnode[node] = fnode
 
     fnodescache.write()
 
     duration = util.timer() - starttime
     ui.log('tagscache',
            '%d/%d cache hits/lookups in %0.4f '
            'seconds\n',
            fnodescache.hitcount, fnodescache.lookupcount, duration)
     return cachefnode
 
 def _writetagcache(ui, repo, valid, cachetags):
     filename = _filename(repo)
     try:
         cachefile = repo.cachevfs(filename, 'w', atomictemp=True)
     except (OSError, IOError):
         return
 
     ui.log('tagscache', 'writing .hg/cache/%s with %d tags\n',
            filename, len(cachetags))
 
     if valid[2]:
         cachefile.write('%d %s %s\n' % (valid[0], hex(valid[1]), hex(valid[2])))
     else:
         cachefile.write('%d %s\n' % (valid[0], hex(valid[1])))
 
     # Tag names in the cache are in UTF-8 -- which is the whole reason
     # we keep them in UTF-8 throughout this module.  If we converted
     # them local encoding on input, we would lose info writing them to
     # the cache.
     for (name, (node, hist)) in sorted(cachetags.iteritems()):
         for n in hist:
             cachefile.write("%s %s\n" % (hex(n), name))
         cachefile.write("%s %s\n" % (hex(node), name))
 
     try:
         cachefile.close()
     except (OSError, IOError):
         pass
 
 def tag(repo, names, node, message, local, user, date, editor=False):
     '''tag a revision with one or more symbolic names.
 
     names is a list of strings or, when adding a single tag, names may be a
     string.
 
     if local is True, the tags are stored in a per-repository file.
     otherwise, they are stored in the .hgtags file, and a new
     changeset is committed with the change.
 
     keyword arguments:
 
     local: whether to store tags in non-version-controlled file
     (default False)
 
     message: commit message to use if committing
 
     user: name of user to use if committing
 
     date: date tuple to use if committing'''
 
     if not local:
         m = matchmod.exact(repo.root, '', ['.hgtags'])
         if any(repo.status(match=m, unknown=True, ignored=True)):
             raise error.Abort(_('working copy of .hgtags is changed'),
                              hint=_('please commit .hgtags manually'))
 
     with repo.wlock():
         repo.tags() # instantiate the cache
-        _tag(repo.unfiltered(), names, node, message, local, user, date,
+        _tag(repo, names, node, message, local, user, date,
              editor=editor)
 
 def _tag(repo, names, node, message, local, user, date, extra=None,
          editor=False):
     if isinstance(names, str):
         names = (names,)
 
     branches = repo.branchmap()
     for name in names:
         repo.hook('pretag', throw=True, node=hex(node), tag=name,
                   local=local)
         if name in branches:
             repo.ui.warn(_("warning: tag %s conflicts with existing"
             " branch name\n") % name)
 
     def writetags(fp, names, munge, prevtags):
         fp.seek(0, 2)
         if prevtags and prevtags[-1] != '\n':
             fp.write('\n')
         for name in names:
             if munge:
                 m = munge(name)
             else:
                 m = name
 
             if (repo._tagscache.tagtypes and
                 name in repo._tagscache.tagtypes):
                 old = repo.tags().get(name, nullid)
                 fp.write('%s %s\n' % (hex(old), m))
             fp.write('%s %s\n' % (hex(node), m))
         fp.close()
 
     prevtags = ''
     if local:
         try:
             fp = repo.vfs('localtags', 'r+')
         except IOError:
             fp = repo.vfs('localtags', 'a')
         else:
             prevtags = fp.read()
 
         # local tags are stored in the current charset
         writetags(fp, names, None, prevtags)
         for name in names:
             repo.hook('tag', node=hex(node), tag=name, local=local)
         return
 
     try:
         fp = repo.wvfs('.hgtags', 'rb+')
     except IOError as e:
         if e.errno != errno.ENOENT:
             raise
         fp = repo.wvfs('.hgtags', 'ab')
     else:
         prevtags = fp.read()
 
     # committed tags are stored in UTF-8
     writetags(fp, names, encoding.fromlocal, prevtags)
 
     fp.close()
 
     repo.invalidatecaches()
 
     if '.hgtags' not in repo.dirstate:
         repo[None].add(['.hgtags'])
 
     m = matchmod.exact(repo.root, '', ['.hgtags'])
     tagnode = repo.commit(message, user, date, extra=extra, match=m,
                           editor=editor)
 
     for name in names:
         repo.hook('tag', node=hex(node), tag=name, local=local)
 
     return tagnode
 
 _fnodescachefile = 'hgtagsfnodes1'
 _fnodesrecsize = 4 + 20 # changeset fragment + filenode
 _fnodesmissingrec = '\xff' * 24
 
 class hgtagsfnodescache(object):
     """Persistent cache mapping revisions to .hgtags filenodes.
 
     The cache is an array of records. Each item in the array corresponds to
     a changelog revision. Values in the array contain the first 4 bytes of
     the node hash and the 20 bytes .hgtags filenode for that revision.
 
     The first 4 bytes are present as a form of verification. Repository
     stripping and rewriting may change the node at a numeric revision in the
     changelog. The changeset fragment serves as a verifier to detect
     rewriting. This logic is shared with the rev branch cache (see
     branchmap.py).
 
     The instance holds in memory the full cache content but entries are
     only parsed on read.
 
     Instances behave like lists. ``c[i]`` works where i is a rev or
     changeset node. Missing indexes are populated automatically on access.
     """
     def __init__(self, repo):
         assert repo.filtername is None
 
         self._repo = repo
 
         # Only for reporting purposes.
         self.lookupcount = 0
         self.hitcount = 0
 
 
         try:
             data = repo.cachevfs.read(_fnodescachefile)
         except (OSError, IOError):
             data = ""
         self._raw = bytearray(data)
 
         # The end state of self._raw is an array that is of the exact length
         # required to hold a record for every revision in the repository.
         # We truncate or extend the array as necessary. self._dirtyoffset is
         # defined to be the start offset at which we need to write the output
         # file. This offset is also adjusted when new entries are calculated
         # for array members.
         cllen = len(repo.changelog)
         wantedlen = cllen * _fnodesrecsize
         rawlen = len(self._raw)
 
         self._dirtyoffset = None
 
         if rawlen < wantedlen:
             self._dirtyoffset = rawlen
             self._raw.extend('\xff' * (wantedlen - rawlen))
         elif rawlen > wantedlen:
             # There's no easy way to truncate array instances. This seems
             # slightly less evil than copying a potentially large array slice.
             for i in range(rawlen - wantedlen):
                 self._raw.pop()
             self._dirtyoffset = len(self._raw)
 
     def getfnode(self, node, computemissing=True):
         """Obtain the filenode of the .hgtags file at a specified revision.
 
         If the value is in the cache, the entry will be validated and returned.
         Otherwise, the filenode will be computed and returned unless
         "computemissing" is False, in which case None will be returned without
         any potentially expensive computation being performed.
 
         If an .hgtags does not exist at the specified revision, nullid is
         returned.
         """
         ctx = self._repo[node]
         rev = ctx.rev()
 
         self.lookupcount += 1
 
         offset = rev * _fnodesrecsize
         record = '%s' % self._raw[offset:offset + _fnodesrecsize]
         properprefix = node[0:4]
 
         # Validate and return existing entry.
         if record != _fnodesmissingrec:
             fileprefix = record[0:4]
 
             if fileprefix == properprefix:
                 self.hitcount += 1
                 return record[4:]
 
             # Fall through.
 
         # If we get here, the entry is either missing or invalid.
 
         if not computemissing:
             return None
 
         # Populate missing entry.
         try:
             fnode = ctx.filenode('.hgtags')
         except error.LookupError:
             # No .hgtags file on this revision.
             fnode = nullid
 
         self._writeentry(offset, properprefix, fnode)
         return fnode
 
     def setfnode(self, node, fnode):
         """Set the .hgtags filenode for a given changeset."""
         assert len(fnode) == 20
         ctx = self._repo[node]
 
         # Do a lookup first to avoid writing if nothing has changed.
         if self.getfnode(ctx.node(), computemissing=False) == fnode:
             return
 
         self._writeentry(ctx.rev() * _fnodesrecsize, node[0:4], fnode)
 
     def _writeentry(self, offset, prefix, fnode):
         # Slices on array instances only accept other array.
         entry = bytearray(prefix + fnode)
         self._raw[offset:offset + _fnodesrecsize] = entry
         # self._dirtyoffset could be None.
         self._dirtyoffset = min(self._dirtyoffset, offset) or 0
 
     def write(self):
         """Perform all necessary writes to cache file.
 
         This may no-op if no writes are needed or if a write lock could
         not be obtained.
         """
         if self._dirtyoffset is None:
             return
 
         data = self._raw[self._dirtyoffset:]
         if not data:
             return
 
         repo = self._repo
 
         try:
             lock = repo.wlock(wait=False)
         except error.LockError:
             repo.ui.log('tagscache', 'not writing .hg/cache/%s because '
                         'lock cannot be acquired\n' % (_fnodescachefile))
             return
 
         try:
             f = repo.cachevfs.open(_fnodescachefile, 'ab')
             try:
                 # if the file has been truncated
                 actualoffset = f.tell()
                 if actualoffset < self._dirtyoffset:
                     self._dirtyoffset = actualoffset
                     data = self._raw[self._dirtyoffset:]
                 f.seek(self._dirtyoffset)
                 f.truncate()
                 repo.ui.log('tagscache',
                             'writing %d bytes to cache/%s\n' % (
                             len(data), _fnodescachefile))
                 f.write(data)
                 self._dirtyoffset = None
             finally:
                 f.close()
         except (IOError, OSError) as inst:
             repo.ui.log('tagscache',
                         "couldn't write cache/%s: %s\n" % (
                         _fnodescachefile, inst))
         finally:
             lock.release()

tests/test-tag.t

@@ -1,749 +1,802
   $ cat >> $HGRCPATH << EOF
   > [experimental]
   > hook-track-tags=1
   > [hooks]
   > txnclose.track-tag=sh ${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'
   >     sed 's/^/hook: /' .hg/changes/tags.changes
   > fi
   > EOF
   $ 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
   hook: +A acb14030fe0a21b60322c440ad2d20cf7685a376 bleah
   $ 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
   hook: +A acb14030fe0a21b60322c440ad2d20cf7685a376 bleah0
   $ hg tag -l -r 1 "bleah1"
   $ hg tag gack gawk gorp
   hook: tag changes detected
   hook: +A 336fccc858a4eb69609a291105009e484a6b6b8d gack
   hook: +A 336fccc858a4eb69609a291105009e484a6b6b8d gawk
   hook: +A 336fccc858a4eb69609a291105009e484a6b6b8d gorp
   $ hg tag -f gack
   hook: tag changes detected
   hook: -M 336fccc858a4eb69609a291105009e484a6b6b8d gack
   hook: +M 799667b6f2d9b957f73fa644a918c2df22bab58f gack
   $ hg tag --remove gack gorp
   hook: tag changes detected
   hook: -R 799667b6f2d9b957f73fa644a918c2df22bab58f gack
   hook: -R 336fccc858a4eb69609a291105009e484a6b6b8d gorp
 
   $ 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
   hook: +A acb14030fe0a21b60322c440ad2d20cf7685a376 bleahbleah
   $ hg tag -r 0 " bleah bleah "
   hook: tag changes detected
   hook: +A acb14030fe0a21b60322c440ad2d20cf7685a376 bleah bleah
 
   $ 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
   hook: +A acb14030fe0a21b60322c440ad2d20cf7685a376 foobar
   $ 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
   hook: +A acb14030fe0a21b60322c440ad2d20cf7685a376 bleah
   $ 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
   hook: +A acb14030fe0a21b60322c440ad2d20cf7685a376 bleah
   hook: +A acb14030fe0a21b60322c440ad2d20cf7685a376 bleah0
   hook: +A 336fccc858a4eb69609a291105009e484a6b6b8d gawk
   $ 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
   hook: +A acb14030fe0a21b60322c440ad2d20cf7685a376 bleah
   $ 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'
   $ cat .hgtags; echo
   acb14030fe0a21b60322c440ad2d20cf7685a376 foobar
   $ hg tag newline
   hook: tag changes detected
   hook: +A a0eea09de1eeec777b46f2085260a373b2fbc293 newline
   $ 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
   hook: +A fc93d2ea1cd78e91216c6cfbbf26747c10ce11ae tag-and-branch-same-name
 
 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
   hook: +A 75a534207be6b03576e0c7a4fa5708d045f1c876 custom-tag
   $ hg log -l1 --template "{desc}\n"
   custom tag message
   second line
 
 
 local tag with .hgtags modified
 
   $ hg tag hgtags-modified
   hook: tag changes detected
   hook: +A 0f26aaea6f74c3ed6c4aad8844403c9ba128d23a hgtags-modified
   $ 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
   hook: -R acb14030fe0a21b60322c440ad2d20cf7685a376 bleah
   hook: -R acb14030fe0a21b60322c440ad2d20cf7685a376 bleah bleah
   hook: -R acb14030fe0a21b60322c440ad2d20cf7685a376 bleah0
   hook: -R acb14030fe0a21b60322c440ad2d20cf7685a376 bleahbleah
   hook: -R 336fccc858a4eb69609a291105009e484a6b6b8d gawk
   $ hg up 13
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ hg tag new-topo-head
   hook: tag changes detected
   hook: +A 0f26aaea6f74c3ed6c4aad8844403c9ba128d23a new-topo-head
 
 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]
 
+issue5539: pruned tags do not appear in .hgtags
+
+  $ cat >> $HGRCPATH << EOF
+  > [experimental]
+  > stabilization=createmarkers,exchange
+  > EOF
+  $ hg up e4d483960b9b --quiet
+  $ echo aaa >>a
+  $ hg ci -maaa
+  $ hg log -r . -T "{node}\n"
+  743b3afd5aa69f130c246806e48ad2e699f490d2
+  $ hg tag issue5539
+  hook: tag changes detected
+  hook: +A 743b3afd5aa69f130c246806e48ad2e699f490d2 issue5539
+  $ cat .hgtags
+  acb14030fe0a21b60322c440ad2d20cf7685a376 foobar
+  a0eea09de1eeec777b46f2085260a373b2fbc293 newline
+  743b3afd5aa69f130c246806e48ad2e699f490d2 issue5539
+  $ hg log -r . -T "{node}\n"
+  abeb261f0508ecebcd345ce21e7a25112df417aa
+(mimic 'hg prune' command by obsoleting current changeset and then moving to its parent)
+  $ hg debugobsolete abeb261f0508ecebcd345ce21e7a25112df417aa --record-parents
+  obsoleted 1 changesets
+  $ hg up ".^" --quiet
+  $ cat .hgtags
+  acb14030fe0a21b60322c440ad2d20cf7685a376 foobar
+  a0eea09de1eeec777b46f2085260a373b2fbc293 newline
+  $ echo bbb >>a
+  $ hg ci -mbbb
+  $ hg log -r . -T "{node}\n"
+  089dd20da58cae34165c37b064539c6ac0c6a0dd
+  $ hg tag issue5539
+  hook: tag changes detected
+  hook: -M 743b3afd5aa69f130c246806e48ad2e699f490d2 issue5539
+  hook: +M 089dd20da58cae34165c37b064539c6ac0c6a0dd issue5539
+  $ hg id
+  0accf560a709 tip
+  $ cat .hgtags
+  acb14030fe0a21b60322c440ad2d20cf7685a376 foobar
+  a0eea09de1eeec777b46f2085260a373b2fbc293 newline
+  089dd20da58cae34165c37b064539c6ac0c6a0dd issue5539
+  $ hg tags
+  tip                               19:0accf560a709
+  issue5539                         18:089dd20da58c
+  new-topo-head                     13:0f26aaea6f74
+  baz                               13:0f26aaea6f74
+  custom-tag                        12:75a534207be6
+  tag-and-branch-same-name          11:fc93d2ea1cd7
+  newline                            9:a0eea09de1ee
+  localnewline                       8:c2899151f4e7
+  localblah                          0:acb14030fe0a
+  foobar                             0:acb14030fe0a
+
   $ 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
   hook: +A be090ea6625635128e90f7d89df8beeb2bcc1653 tag
   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
   hook: +A be090ea6625635128e90f7d89df8beeb2bcc1653 tag
 
 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
   hook: +A 6cee5c8f3e5b4ae1a3996d2f6489c3e08eb5aea7 tbase
   $ 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
   hook: +A 4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t1
   hook: +A 4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t2
   hook: +A 4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t3
   $ hg tag --remove t2
   hook: tag changes detected
   hook: -R 4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t2
   $ hg tag t5
   hook: tag changes detected
   hook: +A 875517b4806a848f942811a315a5bce30804ae85 t5
   $ echo c2 > f2
   $ hg ci -A -m2
   adding f2
   $ hg tag -f t3
   hook: tag changes detected
   hook: -M 4f3e9b90005b68b4d8a3f4355cedc302a8364f5c t3
   hook: +M 79505d5360b07e3e79d1052e347e73c02b8afa5b t3
 
   $ cd ../repo-automatic-tag-merge
   $ echo c3 > f3
   $ hg ci -A -m3
   adding f3
   $ hg tag -f t4 t5 t6
   hook: tag changes detected
   hook: +A 9aa4e1292a27a248f8d07339bed9931d54907be7 t4
   hook: +A 9aa4e1292a27a248f8d07339bed9931d54907be7 t5
   hook: +A 9aa4e1292a27a248f8d07339bed9931d54907be7 t6
 
   $ 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
   hook: -R 9aa4e1292a27a248f8d07339bed9931d54907be7 t5
   $ 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
   hook: +A 929bca7b18d067cbf3844c3896319a940059d748 t2
   $ hg tag -f t6
   hook: tag changes detected
   hook: -M 9aa4e1292a27a248f8d07339bed9931d54907be7 t6
   hook: +M 09af2ce14077a94effef208b49a718f4836d4338 t6
 
   $ 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
   hook: +A 929bca7b18d067cbf3844c3896319a940059d748 t2
   hook: +A 9aa4e1292a27a248f8d07339bed9931d54907be7 t4
   hook: -R 875517b4806a848f942811a315a5bce30804ae85 t5
   hook: +A 09af2ce14077a94effef208b49a718f4836d4338 t6
   (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
   hook: +A b325cc5b642c5b465bdbe8c09627cb372de3d47d t7
   $ 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
   hook: -R 929bca7b18d067cbf3844c3896319a940059d748 t2
   hook: +A 875517b4806a848f942811a315a5bce30804ae85 t5
   hook: -M b325cc5b642c5b465bdbe8c09627cb372de3d47d t7
   hook: +M ea918d56be86a4afc5a95312e8b6750e1428d9d2 t7
   $ 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
   hook: -M ea918d56be86a4afc5a95312e8b6750e1428d9d2 t7
   hook: +M fd3a9e394ce3afb354a496323bf68ac1755a30de t7
   $ 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
   $ 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