diff -r 362e65fc6146 -r 38fbcc760ec6 hgext/evolve.py
--- a/hgext/evolve.py	Tue Sep 11 11:45:00 2012 +0200
+++ b/hgext/evolve.py	Tue Sep 11 12:19:13 2012 +0200
@@ -298,6 +298,8 @@
 ### Obsolescence Caching Logic                                    ###
 #####################################################################
 
+# IN CORE fb72eec7efd8
+
 # Obsolescence related logic can be very slow if we don't have efficient cache.
 #
 # This section implements a cache mechanism that did not make it into core for
@@ -321,58 +323,65 @@
 #:   function take a single "repo" argument.
 #:
 #: Use the `cachefor` decorator to register new cache function
-cachefuncs = {}
-def cachefor(name):
-    """Decorator to register a function as computing the cache for a set"""
-    def decorator(func):
-        assert name not in cachefuncs
-        cachefuncs[name] = func
-        return func
-    return decorator
+try:
+    cachefuncs = obsolete.cachefuncs
+    cachefor = obsolete.cachefor
+    getobscache = obsolete.getobscache
+    clearobscaches = obsolete.clearobscaches
+except AttributeError:
+    cachefuncs = {}
 
-@cachefor('obsolete')
-def _computeobsoleteset(repo):
-    """the set of obsolete revisions"""
-    obs = set()
-    nm = repo.changelog.nodemap
-    for prec in repo.obsstore.precursors:
-        rev = nm.get(prec)
-        if rev is not None:
-            obs.add(rev)
-    return set(repo.revs('%ld - public()', obs))
+    def cachefor(name):
+        """Decorator to register a function as computing the cache for a set"""
+        def decorator(func):
+            assert name not in cachefuncs
+            cachefuncs[name] = func
+            return func
+        return decorator
 
-@cachefor('unstable')
-def _computeunstableset(repo):
-    """the set of non obsolete revisions with obsolete parents"""
-    return set(repo.revs('(obsolete()::) - obsolete()'))
+    @cachefor('obsolete')
+    def _computeobsoleteset(repo):
+        """the set of obsolete revisions"""
+        obs = set()
+        nm = repo.changelog.nodemap
+        for prec in repo.obsstore.precursors:
+            rev = nm.get(prec)
+            if rev is not None:
+                obs.add(rev)
+        return set(repo.revs('%ld - public()', obs))
 
-@cachefor('suspended')
-def _computesuspendedset(repo):
-    """the set of obsolete parents with non obsolete descendants"""
-    return set(repo.revs('obsolete() and obsolete()::unstable()'))
+    @cachefor('unstable')
+    def _computeunstableset(repo):
+        """the set of non obsolete revisions with obsolete parents"""
+        return set(repo.revs('(obsolete()::) - obsolete()'))
 
-@cachefor('extinct')
-def _computeextinctset(repo):
-    """the set of obsolete parents without non obsolete descendants"""
-    return set(repo.revs('obsolete() - obsolete()::unstable()'))
+    @cachefor('suspended')
+    def _computesuspendedset(repo):
+        """the set of obsolete parents with non obsolete descendants"""
+        return set(repo.revs('obsolete() and obsolete()::unstable()'))
 
-@eh.wrapfunction(obsolete.obsstore, '__init__')
-def _initobsstorecache(orig, obsstore, *args, **kwargs):
-    """add a cache attribute to obsstore"""
-    obsstore.caches = {}
-    return orig(obsstore, *args, **kwargs)
+    @cachefor('extinct')
+    def _computeextinctset(repo):
+        """the set of obsolete parents without non obsolete descendants"""
+        return set(repo.revs('obsolete() - obsolete()::unstable()'))
+
+    @eh.wrapfunction(obsolete.obsstore, '__init__')
+    def _initobsstorecache(orig, obsstore, *args, **kwargs):
+        """add a cache attribute to obsstore"""
+        obsstore.caches = {}
+        return orig(obsstore, *args, **kwargs)
 
 ### Cache access
 
-def getobscache(repo, name):
-    """Return the set of revision that belong to the <name> set
+    def getobscache(repo, name):
+        """Return the set of revision that belong to the <name> set
 
-    Such access may compute the set and cache it for future use"""
-    if not repo.obsstore:
-        return ()
-    if name not in repo.obsstore.caches:
-        repo.obsstore.caches[name] = cachefuncs[name](repo)
-    return repo.obsstore.caches[name]
+        Such access may compute the set and cache it for future use"""
+        if not repo.obsstore:
+            return ()
+        if name not in repo.obsstore.caches:
+            repo.obsstore.caches[name] = cachefuncs[name](repo)
+        return repo.obsstore.caches[name]
 
 ### Cache clean up
 #
@@ -384,85 +393,85 @@
 # - strip is used a repo
 
 
-def clearobscaches(repo):
-    """Remove all obsolescence related cache from a repo
+    def clearobscaches(repo):
+        """Remove all obsolescence related cache from a repo
 
-    This remove all cache in obsstore is the obsstore already exist on the
-    repo.
+        This remove all cache in obsstore is the obsstore already exist on the
+        repo.
 
-    (We could be smarter here)"""
-    if 'obsstore' in repo._filecache:
-        repo.obsstore.caches.clear()
+        (We could be smarter here)"""
+        if 'obsstore' in repo._filecache:
+            repo.obsstore.caches.clear()
 
-@eh.wrapfunction(localrepo.localrepository, 'addchangegroup')  # new changeset
-@eh.wrapfunction(phases, 'retractboundary')  # phase movement
-@eh.wrapfunction(phases, 'advanceboundary')  # phase movement
-@eh.wrapfunction(localrepo.localrepository, 'destroyed')  # strip
-def wrapclearcache(orig, repo, *args, **kwargs):
-    try:
-        return orig(repo, *args, **kwargs)
-    finally:
-        # we are a bit wide here
-        # we could restrict to:
-        # advanceboundary + phase==public
-        # retractboundary + phase==draft
-        clearobscaches(repo)
+    @eh.wrapfunction(localrepo.localrepository, 'addchangegroup')  # new changeset
+    @eh.wrapfunction(phases, 'retractboundary')  # phase movement
+    @eh.wrapfunction(phases, 'advanceboundary')  # phase movement
+    @eh.wrapfunction(localrepo.localrepository, 'destroyed')  # strip
+    def wrapclearcache(orig, repo, *args, **kwargs):
+        try:
+            return orig(repo, *args, **kwargs)
+        finally:
+            # we are a bit wide here
+            # we could restrict to:
+            # advanceboundary + phase==public
+            # retractboundary + phase==draft
+            clearobscaches(repo)
 
-@eh.wrapfunction(obsolete.obsstore, 'add')  # new marker
-def clearonadd(orig, obsstore, *args, **kwargs):
-    try:
-        return orig(obsstore, *args, **kwargs)
-    finally:
-        obsstore.caches.clear()
+    @eh.wrapfunction(obsolete.obsstore, 'add')  # new marker
+    def clearonadd(orig, obsstore, *args, **kwargs):
+        try:
+            return orig(obsstore, *args, **kwargs)
+        finally:
+            obsstore.caches.clear()
 
 ### Use the case
 # Function in core that could benefic from the cache are overwritten by cache using version
 
 # changectx method
 
-@eh.addattr(context.changectx, 'unstable')
-def unstable(ctx):
-    """is the changeset unstable (have obsolete ancestor)"""
-    if ctx.node() is None:
-        return False
-    return ctx.rev() in getobscache(ctx._repo, 'unstable')
+    @eh.addattr(context.changectx, 'unstable')
+    def unstable(ctx):
+        """is the changeset unstable (have obsolete ancestor)"""
+        if ctx.node() is None:
+            return False
+        return ctx.rev() in getobscache(ctx._repo, 'unstable')
 
 
-@eh.addattr(context.changectx, 'extinct')
-def extinct(ctx):
-    """is the changeset extinct by other"""
-    if ctx.node() is None:
-        return False
-    return ctx.rev() in getobscache(ctx._repo, 'extinct')
+    @eh.addattr(context.changectx, 'extinct')
+    def extinct(ctx):
+        """is the changeset extinct by other"""
+        if ctx.node() is None:
+            return False
+        return ctx.rev() in getobscache(ctx._repo, 'extinct')
 
 # revset
 
-@eh.revset('obsolete')
-def revsetobsolete(repo, subset, x):
-    """``obsolete()``
-    Changeset is obsolete.
-    """
-    args = revset.getargs(x, 0, 0, 'obsolete takes no argument')
-    obsoletes = getobscache(repo, 'obsolete')
-    return [r for r in subset if r in obsoletes]
+    @eh.revset('obsolete')
+    def revsetobsolete(repo, subset, x):
+        """``obsolete()``
+        Changeset is obsolete.
+        """
+        args = revset.getargs(x, 0, 0, 'obsolete takes no argument')
+        obsoletes = getobscache(repo, 'obsolete')
+        return [r for r in subset if r in obsoletes]
 
-@eh.revset('unstable')
-def revsetunstable(repo, subset, x):
-    """``unstable()``
-    Unstable changesets are non-obsolete with obsolete ancestors.
-    """
-    args = revset.getargs(x, 0, 0, 'unstable takes no arguments')
-    unstables = getobscache(repo, 'unstable')
-    return [r for r in subset if r in unstables]
+    @eh.revset('unstable')
+    def revsetunstable(repo, subset, x):
+        """``unstable()``
+        Unstable changesets are non-obsolete with obsolete ancestors.
+        """
+        args = revset.getargs(x, 0, 0, 'unstable takes no arguments')
+        unstables = getobscache(repo, 'unstable')
+        return [r for r in subset if r in unstables]
 
-@eh.revset('extinct')
-def revsetextinct(repo, subset, x):
-    """``extinct()``
-    Obsolete changesets with obsolete descendants only.
-    """
-    args = revset.getargs(x, 0, 0, 'extinct takes no arguments')
-    extincts = getobscache(repo, 'extinct')
-    return [r for r in subset if r in extincts]
+    @eh.revset('extinct')
+    def revsetextinct(repo, subset, x):
+        """``extinct()``
+        Obsolete changesets with obsolete descendants only.
+        """
+        args = revset.getargs(x, 0, 0, 'extinct takes no arguments')
+        extincts = getobscache(repo, 'extinct')
+        return [r for r in subset if r in extincts]
 
 #####################################################################
 ### Complete troubles computation logic                           ###