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  • Committer: Vincent Ladeuil
  • Date: 2007-10-23 07:15:13 UTC
  • mfrom: (2926 +trunk)
  • mto: (2961.1.1 trunk)
  • mto: This revision was merged to the branch mainline in revision 2962.
  • Revision ID: v.ladeuil+lp@free.fr-20071023071513-elryt6g2at34d2ur
merge bzr.dev

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bzrlib/graph.py
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        return False
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class HeadsCache(object):
 
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    """A cache of results for graph heads calls."""
 
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    def __init__(self, graph):
 
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        self.graph = graph
 
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        self._heads = {}
 
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    def heads(self, keys):
 
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        """Return the heads of keys.
 
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        This matches the API of Graph.heads(), specifically the return value is
 
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        a set which can be mutated, and ordering of the input is not preserved
 
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        in the output.
 
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        :see also: Graph.heads.
 
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        :param keys: The keys to calculate heads for.
 
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        :return: A set containing the heads, which may be mutated without
 
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            affecting future lookups.
 
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        """
 
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        keys = frozenset(keys)
 
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        try:
 
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            return set(self._heads[keys])
 
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        except KeyError:
 
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            heads = self.graph.heads(keys)
 
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            self._heads[keys] = heads
 
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            return set(heads)
 
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class _BreadthFirstSearcher(object):
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    """Parallel search the breadth-first the ancestry of revisions.
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