~bzr-pqm/bzr/bzr.dev

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
# Copyright (C) 2006 Canonical Ltd
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

"""Test locks across all branch implemenations"""

from bzrlib import errors
from bzrlib.tests.branch_implementations.test_branch import TestCaseWithBranch
from bzrlib.tests.lock_helpers import TestPreventLocking, LockWrapper


class TestBranchLocking(TestCaseWithBranch):

    def setUp(self):
        TestCaseWithBranch.setUp(self)
        self.reduceLockdirTimeout()

    def get_instrumented_branch(self):
        """Get a Branch object which has been instrumented"""
        # TODO: jam 20060630 It may be that not all formats have a 
        # 'control_files' member. So we should fail gracefully if
        # not there. But assuming it has them lets us test the exact 
        # lock/unlock order.
        self.locks = []
        b = LockWrapper(self.locks, self.get_branch(), 'b')
        b.repository = LockWrapper(self.locks, b.repository, 'r')
        bcf = b.control_files
        rcf = b.repository.control_files

        # Look out for branch types that reuse their control files
        self.combined_control = bcf is rcf

        b.control_files = LockWrapper(self.locks, b.control_files, 'bc')
        b.repository.control_files = \
            LockWrapper(self.locks, b.repository.control_files, 'rc')
        return b

    def test_01_lock_read(self):
        # Test that locking occurs in the correct order
        b = self.get_instrumented_branch()

        self.assertFalse(b.is_locked())
        self.assertFalse(b.repository.is_locked())
        b.lock_read()
        try:
            self.assertTrue(b.is_locked())
            self.assertTrue(b.repository.is_locked())
        finally:
            b.unlock()
        self.assertFalse(b.is_locked())
        self.assertFalse(b.repository.is_locked())

        self.assertEqual([('b', 'lr', True),
                          ('r', 'lr', True),
                          ('rc', 'lr', True),
                          ('bc', 'lr', True),
                          ('b', 'ul', True),
                          ('bc', 'ul', True),
                          ('r', 'ul', True),
                          ('rc', 'ul', True),
                         ], self.locks)

    def test_02_lock_write(self):
        # Test that locking occurs in the correct order
        b = self.get_instrumented_branch()

        self.assertFalse(b.is_locked())
        self.assertFalse(b.repository.is_locked())
        b.lock_write()
        try:
            self.assertTrue(b.is_locked())
            self.assertTrue(b.repository.is_locked())
        finally:
            b.unlock()
        self.assertFalse(b.is_locked())
        self.assertFalse(b.repository.is_locked())

        self.assertEqual([('b', 'lw', True),
                          ('r', 'lw', True),
                          ('rc', 'lw', True),
                          ('bc', 'lw', True),
                          ('b', 'ul', True),
                          ('bc', 'ul', True),
                          ('r', 'ul', True),
                          ('rc', 'ul', True),
                         ], self.locks)

    def test_03_lock_fail_unlock_repo(self):
        # Make sure branch.unlock() is called, even if there is a
        # failure while unlocking the repository.
        b = self.get_instrumented_branch()
        b.repository.disable_unlock()

        self.assertFalse(b.is_locked())
        self.assertFalse(b.repository.is_locked())
        b.lock_write()
        try:
            self.assertTrue(b.is_locked())
            self.assertTrue(b.repository.is_locked())
            self.assertRaises(TestPreventLocking, b.unlock)
            if self.combined_control:
                self.assertTrue(b.is_locked())
            else:
                self.assertFalse(b.is_locked())
            self.assertTrue(b.repository.is_locked())

            # We unlock the branch control files, even if 
            # we fail to unlock the repository
            self.assertEqual([('b', 'lw', True),
                              ('r', 'lw', True),
                              ('rc', 'lw', True),
                              ('bc', 'lw', True),
                              ('b', 'ul', True),
                              ('bc', 'ul', True),
                              ('r', 'ul', False), 
                             ], self.locks)

        finally:
            # For cleanup purposes, make sure we are unlocked
            b.repository._other.unlock()

    def test_04_lock_fail_unlock_control(self):
        # Make sure repository.unlock() is called, if we fail to unlock self
        b = self.get_instrumented_branch()
        b.control_files.disable_unlock()

        self.assertFalse(b.is_locked())
        self.assertFalse(b.repository.is_locked())
        b.lock_write()
        try:
            self.assertTrue(b.is_locked())
            self.assertTrue(b.repository.is_locked())
            self.assertRaises(TestPreventLocking, b.unlock)
            self.assertTrue(b.is_locked())
            if self.combined_control:
                self.assertTrue(b.repository.is_locked())
            else:
                self.assertFalse(b.repository.is_locked())

            # We unlock the repository even if 
            # we fail to unlock the control files
            self.assertEqual([('b', 'lw', True),
                              ('r', 'lw', True),
                              ('rc', 'lw', True),
                              ('bc', 'lw', True),
                              ('b', 'ul', True),
                              ('bc', 'ul', False),
                              ('r', 'ul', True), 
                              ('rc', 'ul', True), 
                             ], self.locks)

        finally:
            # For cleanup purposes, make sure we are unlocked
            b.control_files._other.unlock()

    def test_05_lock_read_fail_repo(self):
        # Test that the branch is not locked if it cannot lock the repository
        b = self.get_instrumented_branch()
        b.repository.disable_lock_read()

        self.assertRaises(TestPreventLocking, b.lock_read)
        self.assertFalse(b.is_locked())
        self.assertFalse(b.repository.is_locked())

        self.assertEqual([('b', 'lr', True),
                          ('r', 'lr', False), 
                         ], self.locks)

    def test_06_lock_write_fail_repo(self):
        # Test that the branch is not locked if it cannot lock the repository
        b = self.get_instrumented_branch()
        b.repository.disable_lock_write()

        self.assertRaises(TestPreventLocking, b.lock_write)
        self.assertFalse(b.is_locked())
        self.assertFalse(b.repository.is_locked())

        self.assertEqual([('b', 'lw', True),
                          ('r', 'lw', False), 
                         ], self.locks)

    def test_07_lock_read_fail_control(self):
        # Test the repository is unlocked if we can't lock self
        b = self.get_instrumented_branch()
        b.control_files.disable_lock_read()

        self.assertRaises(TestPreventLocking, b.lock_read)
        self.assertFalse(b.is_locked())
        self.assertFalse(b.repository.is_locked())

        self.assertEqual([('b', 'lr', True),
                          ('r', 'lr', True),
                          ('rc', 'lr', True),
                          ('bc', 'lr', False),
                          ('r', 'ul', True),
                          ('rc', 'ul', True),
                         ], self.locks)

    def test_08_lock_write_fail_control(self):
        # Test the repository is unlocked if we can't lock self
        b = self.get_instrumented_branch()
        b.control_files.disable_lock_write()

        self.assertRaises(TestPreventLocking, b.lock_write)
        self.assertFalse(b.is_locked())
        self.assertFalse(b.repository.is_locked())

        self.assertEqual([('b', 'lw', True),
                          ('r', 'lw', True),
                          ('rc', 'lw', True),
                          ('bc', 'lw', False),
                          ('r', 'ul', True),
                          ('rc', 'ul', True),
                         ], self.locks)

    def test_lock_write_returns_None_refuses_tokens(self):
        branch = self.make_branch('b')
        tokens = branch.lock_write()
        try:
            if tokens is not None:
                # This test does not apply, because this lockable supports
                # tokens.
                return
            self.assertRaises(errors.TokenLockingNotSupported,
                              branch.lock_write, tokens=('token','token'))
        finally:
            branch.unlock()

    def test_reentering_lock_write_raises_on_token_mismatch(self):
        branch = self.make_branch('b')
        tokens = branch.lock_write()
        try:
            if tokens is None:
                # This test does not apply, because this lockable refuses
                # tokens.
                return
            branch_token, repo_token = tokens
            different_branch_token = branch_token + 'xxx'
            different_repo_token = repo_token + 'xxx'
            # Re-using the same lockable instance with a different branch token
            # will raise TokenMismatch.
            self.assertRaises(errors.TokenMismatch,
                              branch.lock_write,
                              tokens=(different_branch_token, repo_token))
            # Similarly for a different repository token.
            self.assertRaises(errors.TokenMismatch,
                              branch.lock_write,
                              tokens=(branch_token, different_repo_token))
        finally:
            branch.unlock()

    def test_lock_write_with_nonmatching_token(self):
        branch = self.make_branch('b')
        tokens = branch.lock_write()
        try:
            if tokens is None:
                # This test does not apply, because this branch refuses
                # tokens.
                return
            branch_token, repo_token = tokens
            different_branch_token = branch_token + 'xxx'
            different_repo_token = repo_token + 'xxx'

            new_branch = branch.bzrdir.open_branch()
            # We only want to test the relocking abilities of branch, so use the
            # existing repository object which is already locked.
            new_branch.repository = branch.repository
            self.assertRaises(errors.TokenMismatch,
                              new_branch.lock_write,
                              tokens=(different_branch_token, repo_token))
            self.assertRaises(errors.TokenMismatch,
                              new_branch.lock_write,
                              tokens=(branch_token, different_repo_token))
        finally:
            branch.unlock()


    def test_lock_write_with_matching_token(self):
        """Test that a branch can be locked with a token, if it is already
        locked by that token."""
        branch = self.make_branch('b')
        tokens = branch.lock_write()
        try:
            if tokens is None:
                # This test does not apply, because this branch refuses tokens.
                return
            # The same instance will accept a second lock_write if the specified
            # token matches.
            branch.lock_write(tokens=tokens)
            branch.unlock()
            # Calling lock_write on a new instance for the same lockable will
            # also succeed.
            new_branch = branch.bzrdir.open_branch()
            # We only want to test the relocking abilities of branch, so use the
            # existing repository object which is already locked.
            new_branch.repository = branch.repository
            new_branch.lock_write(tokens=tokens)
            new_branch.unlock()
        finally:
            branch.unlock()

    def test_unlock_after_lock_write_with_tokens(self):
        # If lock_write did not physically acquire the lock (because it was
        # passed some tokens), then unlock should not physically release it.
        branch = self.make_branch('b')
        tokens = branch.lock_write()
        try:
            if tokens is None:
                # This test does not apply, because this lockable refuses
                # tokens.
                return
            new_branch = branch.bzrdir.open_branch()
            # We only want to test the relocking abilities of branch, so use the
            # existing repository object which is already locked.
            new_branch.repository = branch.repository
            new_branch.lock_write(tokens=tokens)
            new_branch.unlock()
            self.assertTrue(branch.get_physical_lock_status()) #XXX
        finally:
            branch.unlock()

    def test_lock_write_with_tokens_fails_when_unlocked(self):
        # Lock and unlock to get superficially valid tokens.  This mimics a
        # likely programming error, where a caller accidentally tries to lock
        # with tokens that are no longer valid (because the original lock was
        # released).
        branch = self.make_branch('b')
        tokens = branch.lock_write()
        branch.unlock()
        if tokens is None:
            # This test does not apply, because this lockable refuses
            # tokens.
            return

        self.assertRaises(errors.TokenMismatch,
                          branch.lock_write, tokens=tokens)

    def test_lock_write_reenter_with_tokens(self):
        branch = self.make_branch('b')
        tokens = branch.lock_write()
        try:
            if tokens is None:
                # This test does not apply, because this lockable refuses
                # tokens.
                return
            # Relock with a token.
            branch.lock_write(tokens=tokens)
            branch.unlock()
        finally:
            branch.unlock()
        # The lock should be unlocked on disk.  Verify that with a new lock
        # instance.
        new_branch = branch.bzrdir.open_branch()
        # Calling lock_write now should work, rather than raise LockContention.
        new_branch.lock_write()
        new_branch.unlock()

    def test_leave_lock_in_place(self):
        branch = self.make_branch('b')
        # Lock the branch, then use leave_lock_in_place so that when we
        # unlock the branch the lock is still held on disk.
        tokens = branch.lock_write()
        try:
            if tokens is None:
                # This test does not apply, because this repository refuses lock
                # tokens.
                self.assertRaises(NotImplementedError, branch.leave_lock_in_place)
                return
            branch.leave_lock_in_place()
        finally:
            branch.unlock()
        # We should be unable to relock the repo.
        self.assertRaises(errors.LockContention, branch.lock_write)

    def test_dont_leave_lock_in_place(self):
        branch = self.make_branch('b')
        # Create a lock on disk.
        tokens = branch.lock_write()
        try:
            if tokens is None:
                # This test does not apply, because this branch refuses lock
                # tokens.
                self.assertRaises(NotImplementedError,
                                  branch.dont_leave_lock_in_place)
                return
            try:
                branch.leave_lock_in_place()
            except NotImplementedError:
                # This branch doesn't support this API.
                return
            branch.repository.leave_lock_in_place()
        finally:
            branch.unlock()
        # Reacquire the lock (with a different branch object) by using the
        # tokens.
        new_branch = branch.bzrdir.open_branch()
        new_branch.lock_write(tokens=tokens)
        # Call dont_leave_lock_in_place, so that the lock will be released by
        # this instance, even though the lock wasn't originally acquired by it.
        new_branch.dont_leave_lock_in_place()
        new_branch.repository.dont_leave_lock_in_place()
        new_branch.unlock()
        # Now the branch is unlocked.  Test this by locking it (without tokens).
        branch.lock_write()
        branch.unlock()