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# Copyright (C) 2005, 2006 Canonical Ltd
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 2 of the License, or
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# (at your option) any later version.
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software
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# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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"""Helper functions/classes for testing locking"""
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from bzrlib import errors
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class TestPreventLocking(errors.LockError):
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"""A test exception for forcing locking failure: %(message)s"""
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class LockWrapper(object):
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"""A wrapper which lets us set locking ability.
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This also lets us record what objects were locked in what order,
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to ensure that locking happens correctly.
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def __init__(self, sequence, other, other_id):
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"""Wrap a locking policy around a given object.
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:param sequence: A list object where we should record actions
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:param other: The object to control policy on
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:param other_id: Something to identify the object by
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self.__dict__['_sequence'] = sequence
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self.__dict__['_other'] = other
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self.__dict__['_other_id'] = other_id
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self.__dict__['_allow_write'] = True
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self.__dict__['_allow_read'] = True
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self.__dict__['_allow_unlock'] = True
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def __getattr__(self, attr):
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return getattr(self._other, attr)
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def __setattr__(self, attr, val):
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return setattr(self._other, attr, val)
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self._sequence.append((self._other_id, 'lr', self._allow_read))
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return self._other.lock_read()
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raise TestPreventLocking('lock_read disabled')
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self._sequence.append((self._other_id, 'lw', self._allow_write))
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return self._other.lock_write()
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raise TestPreventLocking('lock_write disabled')
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self._sequence.append((self._other_id, 'ul', self._allow_unlock))
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if self._allow_unlock:
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return self._other.unlock()
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raise TestPreventLocking('unlock disabled')
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def disable_lock_read(self):
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"""Make a lock_read call fail"""
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self.__dict__['_allow_read'] = False
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def disable_unlock(self):
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"""Make an unlock call fail"""
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self.__dict__['_allow_unlock'] = False
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def disable_lock_write(self):
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"""Make a lock_write call fail"""
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self.__dict__['_allow_write'] = False