diff -r 92e455f2866c -r 23921c17299a mercurial/localrepo.py
--- a/mercurial/localrepo.py	Wed Jan 18 17:11:27 2012 +0100
+++ b/mercurial/localrepo.py	Wed Jan 18 17:23:54 2012 +0100
@@ -37,6 +37,10 @@
         self.baseui = baseui
         self.ui = baseui.copy()
         self._dirtyphases = False
+        # A list of callback to shape the phase if no data were found.
+        # Callback are in the form: func(repo, roots) --> processed root.
+        # This list it to be filled by extension during repo setup
+        self._phasedefaults = []
 
         try:
             self.ui.readconfig(self.join("hgrc"), self.root)