1
# Copyright (C) 2005, 2006 Canonical Ltd
3
# This program is free software; you can redistribute it and/or modify
4
# it under the terms of the GNU General Public License as published by
5
# the Free Software Foundation; either version 2 of the License, or
6
# (at your option) any later version.
8
# This program is distributed in the hope that it will be useful,
9
# but WITHOUT ANY WARRANTY; without even the implied warranty of
10
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11
# GNU General Public License for more details.
13
# You should have received a copy of the GNU General Public License
14
# along with this program; if not, write to the Free Software
15
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17
"""Helper functions/classes for testing locking"""
19
from bzrlib import errors
22
class TestPreventLocking(errors.LockError):
23
"""A test exception for forcing locking failure: %(message)s"""
26
class LockWrapper(object):
27
"""A wrapper which lets us set locking ability.
29
This also lets us record what objects were locked in what order,
30
to ensure that locking happens correctly.
33
def __init__(self, sequence, other, other_id):
34
"""Wrap a locking policy around a given object.
36
:param sequence: A list object where we should record actions
37
:param other: The object to control policy on
38
:param other_id: Something to identify the object by
40
self.__dict__['_sequence'] = sequence
41
self.__dict__['_other'] = other
42
self.__dict__['_other_id'] = other_id
43
self.__dict__['_allow_write'] = True
44
self.__dict__['_allow_read'] = True
45
self.__dict__['_allow_unlock'] = True
47
def __getattr__(self, attr):
48
return getattr(self._other, attr)
50
def __setattr__(self, attr, val):
51
return setattr(self._other, attr, val)
54
self._sequence.append((self._other_id, 'lr', self._allow_read))
56
return self._other.lock_read()
57
raise TestPreventLocking('lock_read disabled')
59
def lock_write(self, token=None):
60
self._sequence.append((self._other_id, 'lw', self._allow_write))
62
return self._other.lock_write()
63
raise TestPreventLocking('lock_write disabled')
66
self._sequence.append((self._other_id, 'ul', self._allow_unlock))
67
if self._allow_unlock:
68
return self._other.unlock()
69
raise TestPreventLocking('unlock disabled')
71
def disable_lock_read(self):
72
"""Make a lock_read call fail"""
73
self.__dict__['_allow_read'] = False
75
def disable_unlock(self):
76
"""Make an unlock call fail"""
77
self.__dict__['_allow_unlock'] = False
79
def disable_lock_write(self):
80
"""Make a lock_write call fail"""
81
self.__dict__['_allow_write'] = False