216     return [r for r in subset if r in cs]

   217 

   218 def _successors(repo, s):

   219     """Successors of a changeset"""

   220     cs = set()

   221     nm = repo.changelog.nodemap

   222     markerbyobj = repo.obsoletestore.objects

   223     for r in s:

   224         for p in markerbyobj.get(repo[r].node(), ()):

   225             for sub in p['subjects']:

   226                 sr = nm.get(sub)

   227                 if sr is not None:

   228                     cs.add(sr)

   229     return cs

   230 

   231 def revsetsuccessors(repo, subset, x):

   232     """successors of a subset"""

   233     s = revset.getset(repo, range(len(repo)), x)

   234     cs = _successors(repo, s)

   235     return [r for r in subset if r in cs]

   236 

   237 def _allsuccessors(repo, s):  # XXX we need a better naming

   238     """transitive successors of a subset"""

   239     toproceed = [repo[r].node() for r in s]

   240     seen = set()

   241     allobjects = repo.obsoletestore.objects

   242     while toproceed:

   243         nc = toproceed.pop()

   244         for mark in allobjects.get(nc, ()):

   245             for sub in mark['subjects']:

   246                 if sub not in seen:

   247                     seen.add(sub)

   248                     toproceed.append(sub)

   249     nm = repo.changelog.nodemap

   250     cs = set()

   251     for s in seen:

   252         sr = nm.get(s)

   253         if sr is not None:

   254             cs.add(sr)

   255     return cs

   256 

   257 def revsetallsuccessors(repo, subset, x):

   258     """obsolete parents"""

   259     s = revset.getset(repo, range(len(repo)), x)

   260     cs = _allsuccessors(repo, s)

   374     revset.symbols["successors"] = revsetsuccessors

   375     revset.symbols["allsuccessors"] = revsetallsuccessors  # bad name