--- a/mercurial/subrepo.py	Mon Dec 16 12:59:32 2013 -0600
+++ b/mercurial/subrepo.py	Wed Nov 13 15:55:30 2013 +0900
@@ -10,6 +10,7 @@
 import stat, subprocess, tarfile
 from i18n import _
 import config, util, node, error, cmdutil, bookmarks, match as matchmod
+import phases
 import pathutil
 hg = None
 propertycache = util.propertycache
@@ -351,6 +352,37 @@
         raise util.Abort(_('unknown subrepo type %s') % state[2])
     return types[state[2]](ctx, path, state[:2])
 
+def newcommitphase(ui, ctx):
+    commitphase = phases.newcommitphase(ui)
+    substate = getattr(ctx, "substate", None)
+    if not substate:
+        return commitphase
+    check = ui.config('phases', 'checksubrepos', 'follow')
+    if check not in ('ignore', 'follow', 'abort'):
+        raise util.Abort(_('invalid phases.checksubrepos configuration: %s')
+                         % (check))
+    if check == 'ignore':
+        return commitphase
+    maxphase = phases.public
+    maxsub = None
+    for s in sorted(substate):
+        sub = ctx.sub(s)
+        subphase = sub.phase(substate[s][1])
+        if maxphase < subphase:
+            maxphase = subphase
+            maxsub = s
+    if commitphase < maxphase:
+        if check == 'abort':
+            raise util.Abort(_("can't commit in %s phase"
+                               " conflicting %s from subrepository %s") %
+                             (phases.phasenames[commitphase],
+                              phases.phasenames[maxphase], maxsub))
+        ui.warn(_("warning: changes are committed in"
+                  " %s phase from subrepository %s\n") %
+                (phases.phasenames[maxphase], maxsub))
+        return maxphase
+    return commitphase
+
 # subrepo classes need to implement the following abstract class:
 
 class abstractsubrepo(object):
@@ -385,6 +417,11 @@
         """
         raise NotImplementedError
 
+    def phase(self, state):
+        """returns phase of specified state in the subrepository.
+        """
+        return phases.public
+
     def remove(self):
         """remove the subrepo
 
@@ -652,6 +689,10 @@
         return node.hex(n)
 
     @annotatesubrepoerror
+    def phase(self, state):
+        return self._repo[state].phase()
+
+    @annotatesubrepoerror
     def remove(self):
         # we can't fully delete the repository as it may contain
         # local-only history