205 

   206 def foreground(repo, nodes):

   207     """return all nodes in the "foreground" of other node

   208 

   209     The foreground of a revision is anything reachable using parent -> children

   210     or precursor -> successor relation. It is very similar to "descendant" but

   211     augmented with obsolescence information.

   212 

   213     Beware that possible obsolescence cycle may result if complex situation.

   214     """

   215     repo = repo.unfiltered()

   216     foreground = set(repo.set('%ln::', nodes))

   217     if repo.obsstore:

   218         # We only need this complicated logic if there is obsolescence

   219         # XXX will probably deserve an optimised revset.

   220         nm = repo.changelog.nodemap

   221         plen = -1

   222         # compute the whole set of successors or descendants

   223         while len(foreground) != plen:

   224             plen = len(foreground)

   225             succs = set(c.node() for c in foreground)

   226             mutable = [c.node() for c in foreground if c.mutable()]

   227             succs.update(allsuccessors(repo.obsstore, mutable))

   228             known = (n for n in succs if n in nm)

   229             foreground = set(repo.set('%ln::', known))

   230     return set(c.node() for c in foreground)