# HG changeset patch
# User Pierre-Yves David <pierre-yves.david@logilab.fr>
# Date 1392859665 28800
# Node ID 895fadf6ba3e1a8c55064acea7ec4174f4fbcd1b
# Parent  66c02a2e8e2f1b639329f91c311bc93713ae1b94
evolve: extend obsstore object to use prune parent information

Now that we have the information, we can use it to build a mapping to access all
marker that prune a children of a node. This is similar to what we do for
successors and precursors.

The performance impact is a few tens of second on my mercurial clone.
Experimenting is worth the trouble.

diff -r 66c02a2e8e2f -r 895fadf6ba3e hgext/evolve.py
--- a/hgext/evolve.py	Thu Feb 13 18:09:54 2014 -0800
+++ b/hgext/evolve.py	Wed Feb 19 17:27:45 2014 -0800
@@ -325,6 +325,31 @@
 def createmarkers(*args, **kwargs):
     return obsolete.createmarkers(*args, **kwargs)
 
+class pruneobsstore(obsolete.obsstore):
+
+    def __init__(self, *args, **kwargs):
+        self.prunedchildren = {}
+        return super(pruneobsstore, self).__init__(*args, **kwargs)
+
+    def _load(self, markers):
+        markers = self._prunedetectingmarkers(markers)
+        return super(pruneobsstore, self)._load(markers)
+
+
+    def _prunedetectingmarkers(self, markers):
+        for m in markers:
+            if not m[1]: # no successors
+                meta = obsolete.decodemeta(m[3])
+                if 'p1' in meta:
+                    p1 = node.bin(meta['p1'])
+                    self.prunedchildren.setdefault(p1, set()).add(m)
+                if 'p2' in meta:
+                    p1 = node.bin(meta['p2'])
+                    self.prunedchildren.setdefault(p2, set()).add(m)
+            yield m
+
+obsolete.obsstore = pruneobsstore
+
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 ### Critical fix                                                  ###
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