evolve: exclude "identical" precursors from the precursors set
I'm not sure it is the right thing to do, but it simply thing a lot for now.
Otherwise, using 'precursors' to find rewind direction become too complex.
This is going to give problematic result in case of prune. Since there are no
other precursors to follow.
This software was downloaded from
https://www.mercurial-scm.org/repo/evolve/
Copyright 2011 Peter Arrenbrecht <peter.arrenbrecht@gmail.com>
Logilab SA <contact@logilab.fr>
Pierre-Yves David <pierre-yves.david@ens-lyon.org>
Patrick Mezard <patrick@mezard.eu>
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On Debian systems, the complete text of the GNU General Public License version
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