[PATCH 3 of 6 phases] phases: add a cache allowing to know in which phase a changeset is

[Pierre-Yves David]

# HG changeset patch
# User Pierre-Yves David <pierre-yves.david at ens-lyon.org>
# Date 1320362420 -3600
# Node ID 397adaea4f4bece4a79ca63d9f814b939f222adb
# Parent  9d9364532b0d84bbe24c619d0a184593a5dfa652
phases: add a cache allowing to know in which phase a changeset is

diff --git a/mercurial/localrepo.py b/mercurial/localrepo.py
--- a/mercurial/localrepo.py
+++ b/mercurial/localrepo.py
@@ -174,6 +174,18 @@
     def _phaseroots(self):
         return phases.readroots(self)
 
+    @propertycache
+    def _phaserev(self):
+        cache = [0] * len(self)
+        for phase in phases.trackedphases:
+            roots = map(self.changelog.rev, self._phaseroots[phase])
+            if roots:
+                for rev in roots:
+                    cache[rev] = phase
+                for rev in self.changelog.descendants(*roots):
+                    cache[rev] = phase
+        return cache
+
     @filecache('00changelog.i', True)
     def changelog(self):
         c = changelog.changelog(self.sopener)