Add a test for the "ephemeral_users_enabled" device policy

chrome/test/pyautolib/chromeos/suid_actions.py

 #!/usr/bin/env python
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Helper script to perform actions as a super-user on ChromeOS.
 
 Needs to be run with superuser privileges, typically using the
 suid_python binary.
 
 Usage:
   sudo python suid_actions.py --action=CleanFlimflamDirs
 """
 
+import logging
 import optparse
 import os
 import shutil
 import sys
 
-
 sys.path.append('/usr/local')  # to import autotest libs.
 from autotest.cros import cryptohome
 
+_AUTO_CLEAR_LOCAL_STATE_MAGIC_FILE = '/root/.forget_usernames'
+
 
 class SuidAction(object):
   """Helper to perform some super-user actions on ChromeOS."""
 
   def _ParseArgs(self):
     parser = optparse.OptionParser()
     parser.add_option(
         '-a', '--action', help='Action to perform.')
     self._options = parser.parse_args()[0]
     if not self._options.action:
@@ skipping 24 matching lines @@
             shutil.rmtree(path)
           else:
             os.remove(path)
     finally:
       os.system('start flimflam')
 
   def RemoveAllCryptohomeVaults(self):
     """Remove any existing cryptohome vaults."""
     cryptohome.remove_all_vaults()
 
+  def DisableLocalStateAutoClearing(self):

[Nirnimesh, 2012/04/12 01:46:24]

If you agree with my previous replies, these need to be removed.

[bartfab (slow), 2012/04/12 12:49:31]

To maximize test coverage, I went with the route of trying to remove the magic
file and continuing with the subset of the test still possible if this fails.

+    """Disable clearing of the local state on session manager startup."""
+    os.system('mount -o remount,rw /')
+    os.remove(_AUTO_CLEAR_LOCAL_STATE_MAGIC_FILE)
+    assert not os.path.exists(_AUTO_CLEAR_LOCAL_STATE_MAGIC_FILE)
+    os.system('mount -o remount,ro /')
+    logging.debug('Removed %s. Session manager will not clear local state on '
+                  'startup.' % _AUTO_CLEAR_LOCAL_STATE_MAGIC_FILE)
+
+  def EnableLocalStateAutoClearing(self):
+    """Enable clearing of the local state on session manager startup."""
+    os.system('mount -o remount,rw /')
+    open(_AUTO_CLEAR_LOCAL_STATE_MAGIC_FILE, 'w').close()
+    assert os.path.exists(_AUTO_CLEAR_LOCAL_STATE_MAGIC_FILE)
+    os.system('mount -o remount,ro /')
+    logging.debug('Created %s. Session manager will clear local state on '
+                  'startup.' % _AUTO_CLEAR_LOCAL_STATE_MAGIC_FILE)
+
 
 if __name__ == '__main__':
   sys.exit(SuidAction().Run())