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  • Committer: Aaron Bentley
  • Date: 2008-12-03 05:31:27 UTC
  • mto: This revision was merged to the branch mainline in revision 3893.
  • Revision ID: aaron@aaronbentley.com-20081203053127-vozu5rmsixaadw0v
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1
# Copyright (C) 2007 Canonical Ltd
 
2
#
 
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.
 
7
#
 
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.
 
12
#
 
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
 
16
 
 
17
from bzrlib import (
 
18
    errors,
 
19
    graph as _mod_graph,
 
20
    symbol_versioning,
 
21
    tests,
 
22
    )
 
23
from bzrlib.revision import NULL_REVISION
 
24
from bzrlib.tests import TestCaseWithMemoryTransport
 
25
 
 
26
 
 
27
# Ancestry 1:
 
28
#
 
29
#  NULL_REVISION
 
30
#       |
 
31
#     rev1
 
32
#      /\
 
33
#  rev2a rev2b
 
34
#     |    |
 
35
#   rev3  /
 
36
#     |  /
 
37
#   rev4
 
38
ancestry_1 = {'rev1': [NULL_REVISION], 'rev2a': ['rev1'], 'rev2b': ['rev1'],
 
39
              'rev3': ['rev2a'], 'rev4': ['rev3', 'rev2b']}
 
40
 
 
41
 
 
42
# Ancestry 2:
 
43
#
 
44
#  NULL_REVISION
 
45
#    /    \
 
46
# rev1a  rev1b
 
47
#   |
 
48
# rev2a
 
49
#   |
 
50
# rev3a
 
51
#   |
 
52
# rev4a
 
53
ancestry_2 = {'rev1a': [NULL_REVISION], 'rev2a': ['rev1a'],
 
54
              'rev1b': [NULL_REVISION], 'rev3a': ['rev2a'], 'rev4a': ['rev3a']}
 
55
 
 
56
 
 
57
# Criss cross ancestry
 
58
#
 
59
#     NULL_REVISION
 
60
#         |
 
61
#        rev1
 
62
#        /  \
 
63
#    rev2a  rev2b
 
64
#       |\  /|
 
65
#       |  X |
 
66
#       |/  \|
 
67
#    rev3a  rev3b
 
68
criss_cross = {'rev1': [NULL_REVISION], 'rev2a': ['rev1'], 'rev2b': ['rev1'],
 
69
               'rev3a': ['rev2a', 'rev2b'], 'rev3b': ['rev2b', 'rev2a']}
 
70
 
 
71
 
 
72
# Criss-cross 2
 
73
#
 
74
#  NULL_REVISION
 
75
#    /   \
 
76
# rev1a  rev1b
 
77
#   |\   /|
 
78
#   | \ / |
 
79
#   |  X  |
 
80
#   | / \ |
 
81
#   |/   \|
 
82
# rev2a  rev2b
 
83
criss_cross2 = {'rev1a': [NULL_REVISION], 'rev1b': [NULL_REVISION],
 
84
                'rev2a': ['rev1a', 'rev1b'], 'rev2b': ['rev1b', 'rev1a']}
 
85
 
 
86
 
 
87
# Mainline:
 
88
#
 
89
#  NULL_REVISION
 
90
#       |
 
91
#      rev1
 
92
#      /  \
 
93
#      | rev2b
 
94
#      |  /
 
95
#     rev2a
 
96
mainline = {'rev1': [NULL_REVISION], 'rev2a': ['rev1', 'rev2b'],
 
97
            'rev2b': ['rev1']}
 
98
 
 
99
 
 
100
# feature branch:
 
101
#
 
102
#  NULL_REVISION
 
103
#       |
 
104
#      rev1
 
105
#       |
 
106
#     rev2b
 
107
#       |
 
108
#     rev3b
 
109
feature_branch = {'rev1': [NULL_REVISION],
 
110
                  'rev2b': ['rev1'], 'rev3b': ['rev2b']}
 
111
 
 
112
 
 
113
# History shortcut
 
114
#  NULL_REVISION
 
115
#       |
 
116
#     rev1------
 
117
#     /  \      \
 
118
#  rev2a rev2b rev2c
 
119
#    |  /   \   /
 
120
#  rev3a    rev3b
 
121
history_shortcut = {'rev1': [NULL_REVISION], 'rev2a': ['rev1'],
 
122
                    'rev2b': ['rev1'], 'rev2c': ['rev1'],
 
123
                    'rev3a': ['rev2a', 'rev2b'], 'rev3b': ['rev2b', 'rev2c']}
 
124
 
 
125
# Extended history shortcut
 
126
#  NULL_REVISION
 
127
#       |
 
128
#       a
 
129
#       |\
 
130
#       b |
 
131
#       | |
 
132
#       c |
 
133
#       | |
 
134
#       d |
 
135
#       |\|
 
136
#       e f
 
137
extended_history_shortcut = {'a': [NULL_REVISION],
 
138
                             'b': ['a'],
 
139
                             'c': ['b'],
 
140
                             'd': ['c'],
 
141
                             'e': ['d'],
 
142
                             'f': ['a', 'd'],
 
143
                            }
 
144
 
 
145
# Double shortcut
 
146
# Both sides will see 'A' first, even though it is actually a decendent of a
 
147
# different common revision.
 
148
#
 
149
#  NULL_REVISION
 
150
#       |
 
151
#       a
 
152
#      /|\
 
153
#     / b \
 
154
#    /  |  \
 
155
#   |   c   |
 
156
#   |  / \  |
 
157
#   | d   e |
 
158
#   |/     \|
 
159
#   f       g
 
160
 
 
161
double_shortcut = {'a':[NULL_REVISION], 'b':['a'], 'c':['b'],
 
162
                   'd':['c'], 'e':['c'], 'f':['a', 'd'],
 
163
                   'g':['a', 'e']}
 
164
 
 
165
# Complex shortcut
 
166
# This has a failure mode in that a shortcut will find some nodes in common,
 
167
# but the common searcher won't have time to find that one branch is actually
 
168
# in common. The extra nodes at the beginning are because we want to avoid
 
169
# walking off the graph. Specifically, node G should be considered common, but
 
170
# is likely to be seen by M long before the common searcher finds it.
 
171
#
 
172
# NULL_REVISION
 
173
#     |
 
174
#     a
 
175
#     |
 
176
#     b
 
177
#     |
 
178
#     c
 
179
#     |
 
180
#     d
 
181
#     |\
 
182
#     e f
 
183
#     | |\
 
184
#     | g h
 
185
#     |/| |
 
186
#     i j |
 
187
#     | | |
 
188
#     | k |
 
189
#     | | |
 
190
#     | l |
 
191
#     |/|/
 
192
#     m n
 
193
complex_shortcut = {'a':[NULL_REVISION], 'b':['a'], 'c':['b'], 'd':['c'],
 
194
                    'e':['d'], 'f':['d'], 'g':['f'], 'h':['f'],
 
195
                    'i':['e', 'g'], 'j':['g'], 'k':['j'],
 
196
                    'l':['k'], 'm':['i', 'l'], 'n':['l', 'h']}
 
197
 
 
198
# NULL_REVISION
 
199
#     |
 
200
#     a
 
201
#     |
 
202
#     b
 
203
#     |
 
204
#     c
 
205
#     |
 
206
#     d
 
207
#     |\
 
208
#     e |
 
209
#     | |
 
210
#     f |
 
211
#     | |
 
212
#     g h
 
213
#     | |\
 
214
#     i | j
 
215
#     |\| |
 
216
#     | k |
 
217
#     | | |
 
218
#     | l |
 
219
#     | | |
 
220
#     | m |
 
221
#     | | |
 
222
#     | n |
 
223
#     | | |
 
224
#     | o |
 
225
#     | | |
 
226
#     | p |
 
227
#     | | |
 
228
#     | q |
 
229
#     | | |
 
230
#     | r |
 
231
#     | | |
 
232
#     | s |
 
233
#     | | |
 
234
#     |/|/
 
235
#     t u
 
236
complex_shortcut2 = {'a':[NULL_REVISION], 'b':['a'], 'c':['b'], 'd':['c'],
 
237
                    'e':['d'], 'f':['e'], 'g':['f'], 'h':['d'], 'i':['g'],
 
238
                    'j':['h'], 'k':['h', 'i'], 'l':['k'], 'm':['l'], 'n':['m'],
 
239
                    'o':['n'], 'p':['o'], 'q':['p'], 'r':['q'], 's':['r'],
 
240
                    't':['i', 's'], 'u':['s', 'j'], 
 
241
                    }
 
242
 
 
243
# Graph where different walkers will race to find the common and uncommon
 
244
# nodes.
 
245
#
 
246
# NULL_REVISION
 
247
#     |
 
248
#     a
 
249
#     |
 
250
#     b
 
251
#     |
 
252
#     c
 
253
#     |
 
254
#     d
 
255
#     |\
 
256
#     e k
 
257
#     | |
 
258
#     f-+-p
 
259
#     | | |
 
260
#     | l |
 
261
#     | | |
 
262
#     | m |
 
263
#     | |\|
 
264
#     g n q
 
265
#     |\| |
 
266
#     h o |
 
267
#     |/| |
 
268
#     i r |
 
269
#     | | |
 
270
#     | s |
 
271
#     | | |
 
272
#     | t |
 
273
#     | | |
 
274
#     | u |
 
275
#     | | |
 
276
#     | v |
 
277
#     | | |
 
278
#     | w |
 
279
#     | | |
 
280
#     | x |
 
281
#     | |\|
 
282
#     | y z
 
283
#     |/
 
284
#     j
 
285
#
 
286
# x is found to be common right away, but is the start of a long series of
 
287
# common commits.
 
288
# o is actually common, but the i-j shortcut makes it look like it is actually
 
289
# unique to j at first, you have to traverse all of x->o to find it.
 
290
# q,m gives the walker from j a common point to stop searching, as does p,f.
 
291
# k-n exists so that the second pass still has nodes that are worth searching,
 
292
# rather than instantly cancelling the extra walker.
 
293
 
 
294
racing_shortcuts = {'a':[NULL_REVISION], 'b':['a'], 'c':['b'], 'd':['c'],
 
295
    'e':['d'], 'f':['e'], 'g':['f'], 'h':['g'], 'i':['h', 'o'], 'j':['i', 'y'],
 
296
    'k':['d'], 'l':['k'], 'm':['l'], 'n':['m'], 'o':['n', 'g'], 'p':['f'],
 
297
    'q':['p', 'm'], 'r':['o'], 's':['r'], 't':['s'], 'u':['t'], 'v':['u'],
 
298
    'w':['v'], 'x':['w'], 'y':['x'], 'z':['x', 'q']}
 
299
 
 
300
 
 
301
# A graph with multiple nodes unique to one side.
 
302
#
 
303
# NULL_REVISION
 
304
#     |
 
305
#     a
 
306
#     |
 
307
#     b
 
308
#     |
 
309
#     c
 
310
#     |
 
311
#     d
 
312
#     |\
 
313
#     e f
 
314
#     |\ \
 
315
#     g h i
 
316
#     |\ \ \
 
317
#     j k l m
 
318
#     | |/ x|
 
319
#     | n o p
 
320
#     | |/  |
 
321
#     | q   |
 
322
#     | |   |
 
323
#     | r   |
 
324
#     | |   |
 
325
#     | s   |
 
326
#     | |   |
 
327
#     | t   |
 
328
#     | |   |
 
329
#     | u   |
 
330
#     | |   |
 
331
#     | v   |
 
332
#     | |   |
 
333
#     | w   |
 
334
#     | |   |
 
335
#     | x   |
 
336
#     |/ \ /
 
337
#     y   z
 
338
#
 
339
 
 
340
multiple_interesting_unique = {'a':[NULL_REVISION], 'b':['a'], 'c':['b'],
 
341
    'd':['c'], 'e':['d'], 'f':['d'], 'g':['e'], 'h':['e'], 'i':['f'],
 
342
    'j':['g'], 'k':['g'], 'l':['h'], 'm':['i'], 'n':['k', 'l'],
 
343
    'o':['m'], 'p':['m', 'l'], 'q':['n', 'o'], 'r':['q'], 's':['r'],
 
344
    't':['s'], 'u':['t'], 'v':['u'], 'w':['v'], 'x':['w'],
 
345
    'y':['j', 'x'], 'z':['x', 'p']}
 
346
 
 
347
 
 
348
# Shortcut with extra root
 
349
# We have a long history shortcut, and an extra root, which is why we can't
 
350
# stop searchers based on seeing NULL_REVISION
 
351
#  NULL_REVISION
 
352
#       |   |
 
353
#       a   |
 
354
#       |\  |
 
355
#       b | |
 
356
#       | | |
 
357
#       c | |
 
358
#       | | |
 
359
#       d | g
 
360
#       |\|/
 
361
#       e f
 
362
shortcut_extra_root = {'a': [NULL_REVISION],
 
363
                       'b': ['a'],
 
364
                       'c': ['b'],
 
365
                       'd': ['c'],
 
366
                       'e': ['d'],
 
367
                       'f': ['a', 'd', 'g'],
 
368
                       'g': [NULL_REVISION],
 
369
                      }
 
370
 
 
371
#  NULL_REVISION
 
372
#       |
 
373
#       f
 
374
#       |
 
375
#       e
 
376
#      / \
 
377
#     b   d
 
378
#     | \ |
 
379
#     a   c
 
380
 
 
381
boundary = {'a': ['b'], 'c': ['b', 'd'], 'b':['e'], 'd':['e'], 'e': ['f'],
 
382
            'f':[NULL_REVISION]}
 
383
 
 
384
 
 
385
# A graph that contains a ghost
 
386
#  NULL_REVISION
 
387
#       |
 
388
#       f
 
389
#       |
 
390
#       e   g
 
391
#      / \ /
 
392
#     b   d
 
393
#     | \ |
 
394
#     a   c
 
395
 
 
396
with_ghost = {'a': ['b'], 'c': ['b', 'd'], 'b':['e'], 'd':['e', 'g'],
 
397
              'e': ['f'], 'f':[NULL_REVISION], NULL_REVISION:()}
 
398
 
 
399
# A graph that shows we can shortcut finding revnos when reaching them from the
 
400
# side.
 
401
#  NULL_REVISION
 
402
#       |
 
403
#       a
 
404
#       |
 
405
#       b
 
406
#       |
 
407
#       c
 
408
#       |
 
409
#       d
 
410
#       |
 
411
#       e
 
412
#      / \
 
413
#     f   g
 
414
#     |
 
415
#     h
 
416
#     |
 
417
#     i
 
418
 
 
419
with_tail = {'a':[NULL_REVISION], 'b':['a'], 'c':['b'], 'd':['c'], 'e':['d'],
 
420
             'f':['e'], 'g':['e'], 'h':['f'], 'i':['h']}
 
421
 
 
422
 
 
423
class InstrumentedParentsProvider(object):
 
424
 
 
425
    def __init__(self, parents_provider):
 
426
        self.calls = []
 
427
        self._real_parents_provider = parents_provider
 
428
 
 
429
    def get_parent_map(self, nodes):
 
430
        self.calls.extend(nodes)
 
431
        return self._real_parents_provider.get_parent_map(nodes)
 
432
 
 
433
 
 
434
class TestGraphBase(tests.TestCase):
 
435
 
 
436
    def make_graph(self, ancestors):
 
437
        return _mod_graph.Graph(_mod_graph.DictParentsProvider(ancestors))
 
438
 
 
439
    def make_breaking_graph(self, ancestors, break_on):
 
440
        """Make a Graph that raises an exception if we hit a node."""
 
441
        g = self.make_graph(ancestors)
 
442
        orig_parent_map = g.get_parent_map
 
443
        def get_parent_map(keys):
 
444
            bad_keys = set(keys).intersection(break_on)
 
445
            if bad_keys:
 
446
                self.fail('key(s) %s was accessed' % (sorted(bad_keys),))
 
447
            return orig_parent_map(keys)
 
448
        g.get_parent_map = get_parent_map
 
449
        return g
 
450
 
 
451
 
 
452
class TestGraph(TestCaseWithMemoryTransport):
 
453
 
 
454
    def make_graph(self, ancestors):
 
455
        return _mod_graph.Graph(_mod_graph.DictParentsProvider(ancestors))
 
456
 
 
457
    def prepare_memory_tree(self, location):
 
458
        tree = self.make_branch_and_memory_tree(location)
 
459
        tree.lock_write()
 
460
        tree.add('.')
 
461
        return tree
 
462
 
 
463
    def build_ancestry(self, tree, ancestors):
 
464
        """Create an ancestry as specified by a graph dict
 
465
 
 
466
        :param tree: A tree to use
 
467
        :param ancestors: a dict of {node: [node_parent, ...]}
 
468
        """
 
469
        pending = [NULL_REVISION]
 
470
        descendants = {}
 
471
        for descendant, parents in ancestors.iteritems():
 
472
            for parent in parents:
 
473
                descendants.setdefault(parent, []).append(descendant)
 
474
        while len(pending) > 0:
 
475
            cur_node = pending.pop()
 
476
            for descendant in descendants.get(cur_node, []):
 
477
                if tree.branch.repository.has_revision(descendant):
 
478
                    continue
 
479
                parents = [p for p in ancestors[descendant] if p is not
 
480
                           NULL_REVISION]
 
481
                if len([p for p in parents if not
 
482
                    tree.branch.repository.has_revision(p)]) > 0:
 
483
                    continue
 
484
                tree.set_parent_ids(parents)
 
485
                if len(parents) > 0:
 
486
                    left_parent = parents[0]
 
487
                else:
 
488
                    left_parent = NULL_REVISION
 
489
                tree.branch.set_last_revision_info(
 
490
                    len(tree.branch._lefthand_history(left_parent)),
 
491
                    left_parent)
 
492
                tree.commit(descendant, rev_id=descendant)
 
493
                pending.append(descendant)
 
494
 
 
495
    def test_lca(self):
 
496
        """Test finding least common ancestor.
 
497
 
 
498
        ancestry_1 should always have a single common ancestor
 
499
        """
 
500
        graph = self.make_graph(ancestry_1)
 
501
        self.assertRaises(errors.InvalidRevisionId, graph.find_lca, None)
 
502
        self.assertEqual(set([NULL_REVISION]),
 
503
                         graph.find_lca(NULL_REVISION, NULL_REVISION))
 
504
        self.assertEqual(set([NULL_REVISION]),
 
505
                         graph.find_lca(NULL_REVISION, 'rev1'))
 
506
        self.assertEqual(set(['rev1']), graph.find_lca('rev1', 'rev1'))
 
507
        self.assertEqual(set(['rev1']), graph.find_lca('rev2a', 'rev2b'))
 
508
 
 
509
    def test_no_unique_lca(self):
 
510
        """Test error when one revision is not in the graph"""
 
511
        graph = self.make_graph(ancestry_1)
 
512
        self.assertRaises(errors.NoCommonAncestor, graph.find_unique_lca,
 
513
                          'rev1', '1rev')
 
514
 
 
515
    def test_lca_criss_cross(self):
 
516
        """Test least-common-ancestor after a criss-cross merge."""
 
517
        graph = self.make_graph(criss_cross)
 
518
        self.assertEqual(set(['rev2a', 'rev2b']),
 
519
                         graph.find_lca('rev3a', 'rev3b'))
 
520
        self.assertEqual(set(['rev2b']),
 
521
                         graph.find_lca('rev3a', 'rev3b', 'rev2b'))
 
522
 
 
523
    def test_lca_shortcut(self):
 
524
        """Test least-common ancestor on this history shortcut"""
 
525
        graph = self.make_graph(history_shortcut)
 
526
        self.assertEqual(set(['rev2b']), graph.find_lca('rev3a', 'rev3b'))
 
527
 
 
528
    def test_recursive_unique_lca(self):
 
529
        """Test finding a unique least common ancestor.
 
530
 
 
531
        ancestry_1 should always have a single common ancestor
 
532
        """
 
533
        graph = self.make_graph(ancestry_1)
 
534
        self.assertEqual(NULL_REVISION,
 
535
                         graph.find_unique_lca(NULL_REVISION, NULL_REVISION))
 
536
        self.assertEqual(NULL_REVISION,
 
537
                         graph.find_unique_lca(NULL_REVISION, 'rev1'))
 
538
        self.assertEqual('rev1', graph.find_unique_lca('rev1', 'rev1'))
 
539
        self.assertEqual('rev1', graph.find_unique_lca('rev2a', 'rev2b'))
 
540
        self.assertEqual(('rev1', 1,),
 
541
                         graph.find_unique_lca('rev2a', 'rev2b',
 
542
                         count_steps=True))
 
543
 
 
544
    def assertRemoveDescendants(self, expected, graph, revisions):
 
545
        parents = graph.get_parent_map(revisions)
 
546
        self.assertEqual(expected,
 
547
                         graph._remove_simple_descendants(revisions, parents))
 
548
 
 
549
    def test__remove_simple_descendants(self):
 
550
        graph = self.make_graph(ancestry_1)
 
551
        self.assertRemoveDescendants(set(['rev1']), graph,
 
552
            set(['rev1', 'rev2a', 'rev2b', 'rev3', 'rev4']))
 
553
 
 
554
    def test__remove_simple_descendants_disjoint(self):
 
555
        graph = self.make_graph(ancestry_1)
 
556
        self.assertRemoveDescendants(set(['rev1', 'rev3']), graph,
 
557
            set(['rev1', 'rev3']))
 
558
 
 
559
    def test__remove_simple_descendants_chain(self):
 
560
        graph = self.make_graph(ancestry_1)
 
561
        self.assertRemoveDescendants(set(['rev1']), graph,
 
562
            set(['rev1', 'rev2a', 'rev3']))
 
563
 
 
564
    def test__remove_simple_descendants_siblings(self):
 
565
        graph = self.make_graph(ancestry_1)
 
566
        self.assertRemoveDescendants(set(['rev2a', 'rev2b']), graph,
 
567
            set(['rev2a', 'rev2b', 'rev3']))
 
568
 
 
569
    def test_unique_lca_criss_cross(self):
 
570
        """Ensure we don't pick non-unique lcas in a criss-cross"""
 
571
        graph = self.make_graph(criss_cross)
 
572
        self.assertEqual('rev1', graph.find_unique_lca('rev3a', 'rev3b'))
 
573
        lca, steps = graph.find_unique_lca('rev3a', 'rev3b', count_steps=True)
 
574
        self.assertEqual('rev1', lca)
 
575
        self.assertEqual(2, steps)
 
576
 
 
577
    def test_unique_lca_null_revision(self):
 
578
        """Ensure we pick NULL_REVISION when necessary"""
 
579
        graph = self.make_graph(criss_cross2)
 
580
        self.assertEqual('rev1b', graph.find_unique_lca('rev2a', 'rev1b'))
 
581
        self.assertEqual(NULL_REVISION,
 
582
                         graph.find_unique_lca('rev2a', 'rev2b'))
 
583
 
 
584
    def test_unique_lca_null_revision2(self):
 
585
        """Ensure we pick NULL_REVISION when necessary"""
 
586
        graph = self.make_graph(ancestry_2)
 
587
        self.assertEqual(NULL_REVISION,
 
588
                         graph.find_unique_lca('rev4a', 'rev1b'))
 
589
 
 
590
    def test_lca_double_shortcut(self):
 
591
        graph = self.make_graph(double_shortcut)
 
592
        self.assertEqual('c', graph.find_unique_lca('f', 'g'))
 
593
 
 
594
    def test_common_ancestor_two_repos(self):
 
595
        """Ensure we do unique_lca using data from two repos"""
 
596
        mainline_tree = self.prepare_memory_tree('mainline')
 
597
        self.build_ancestry(mainline_tree, mainline)
 
598
        self.addCleanup(mainline_tree.unlock)
 
599
 
 
600
        # This is cheating, because the revisions in the graph are actually
 
601
        # different revisions, despite having the same revision-id.
 
602
        feature_tree = self.prepare_memory_tree('feature')
 
603
        self.build_ancestry(feature_tree, feature_branch)
 
604
        self.addCleanup(feature_tree.unlock)
 
605
 
 
606
        graph = mainline_tree.branch.repository.get_graph(
 
607
            feature_tree.branch.repository)
 
608
        self.assertEqual('rev2b', graph.find_unique_lca('rev2a', 'rev3b'))
 
609
 
 
610
    def test_graph_difference(self):
 
611
        graph = self.make_graph(ancestry_1)
 
612
        self.assertEqual((set(), set()), graph.find_difference('rev1', 'rev1'))
 
613
        self.assertEqual((set(), set(['rev1'])),
 
614
                         graph.find_difference(NULL_REVISION, 'rev1'))
 
615
        self.assertEqual((set(['rev1']), set()),
 
616
                         graph.find_difference('rev1', NULL_REVISION))
 
617
        self.assertEqual((set(['rev2a', 'rev3']), set(['rev2b'])),
 
618
                         graph.find_difference('rev3', 'rev2b'))
 
619
        self.assertEqual((set(['rev4', 'rev3', 'rev2a']), set()),
 
620
                         graph.find_difference('rev4', 'rev2b'))
 
621
 
 
622
    def test_graph_difference_separate_ancestry(self):
 
623
        graph = self.make_graph(ancestry_2)
 
624
        self.assertEqual((set(['rev1a']), set(['rev1b'])),
 
625
                         graph.find_difference('rev1a', 'rev1b'))
 
626
        self.assertEqual((set(['rev1a', 'rev2a', 'rev3a', 'rev4a']),
 
627
                          set(['rev1b'])),
 
628
                         graph.find_difference('rev4a', 'rev1b'))
 
629
 
 
630
    def test_graph_difference_criss_cross(self):
 
631
        graph = self.make_graph(criss_cross)
 
632
        self.assertEqual((set(['rev3a']), set(['rev3b'])),
 
633
                         graph.find_difference('rev3a', 'rev3b'))
 
634
        self.assertEqual((set([]), set(['rev3b', 'rev2b'])),
 
635
                         graph.find_difference('rev2a', 'rev3b'))
 
636
 
 
637
    def test_graph_difference_extended_history(self):
 
638
        graph = self.make_graph(extended_history_shortcut)
 
639
        self.assertEqual((set(['e']), set(['f'])),
 
640
                         graph.find_difference('e', 'f'))
 
641
        self.assertEqual((set(['f']), set(['e'])),
 
642
                         graph.find_difference('f', 'e'))
 
643
 
 
644
    def test_graph_difference_double_shortcut(self):
 
645
        graph = self.make_graph(double_shortcut)
 
646
        self.assertEqual((set(['d', 'f']), set(['e', 'g'])),
 
647
                         graph.find_difference('f', 'g'))
 
648
 
 
649
    def test_graph_difference_complex_shortcut(self):
 
650
        graph = self.make_graph(complex_shortcut)
 
651
        self.assertEqual((set(['m', 'i', 'e']), set(['n', 'h'])),
 
652
                         graph.find_difference('m', 'n'))
 
653
 
 
654
    def test_graph_difference_complex_shortcut2(self):
 
655
        graph = self.make_graph(complex_shortcut2)
 
656
        self.assertEqual((set(['t']), set(['j', 'u'])),
 
657
                         graph.find_difference('t', 'u'))
 
658
 
 
659
    def test_graph_difference_shortcut_extra_root(self):
 
660
        graph = self.make_graph(shortcut_extra_root)
 
661
        self.assertEqual((set(['e']), set(['f', 'g'])),
 
662
                         graph.find_difference('e', 'f'))
 
663
 
 
664
    def test_stacked_parents_provider(self):
 
665
        parents1 = _mod_graph.DictParentsProvider({'rev2': ['rev3']})
 
666
        parents2 = _mod_graph.DictParentsProvider({'rev1': ['rev4']})
 
667
        stacked = _mod_graph._StackedParentsProvider([parents1, parents2])
 
668
        self.assertEqual({'rev1':['rev4'], 'rev2':['rev3']},
 
669
                         stacked.get_parent_map(['rev1', 'rev2']))
 
670
        self.assertEqual({'rev2':['rev3'], 'rev1':['rev4']},
 
671
                         stacked.get_parent_map(['rev2', 'rev1']))
 
672
        self.assertEqual({'rev2':['rev3']},
 
673
                         stacked.get_parent_map(['rev2', 'rev2']))
 
674
        self.assertEqual({'rev1':['rev4']},
 
675
                         stacked.get_parent_map(['rev1', 'rev1']))
 
676
 
 
677
    def test_iter_topo_order(self):
 
678
        graph = self.make_graph(ancestry_1)
 
679
        args = ['rev2a', 'rev3', 'rev1']
 
680
        topo_args = list(graph.iter_topo_order(args))
 
681
        self.assertEqual(set(args), set(topo_args))
 
682
        self.assertTrue(topo_args.index('rev2a') > topo_args.index('rev1'))
 
683
        self.assertTrue(topo_args.index('rev2a') < topo_args.index('rev3'))
 
684
 
 
685
    def test_is_ancestor(self):
 
686
        graph = self.make_graph(ancestry_1)
 
687
        self.assertEqual(True, graph.is_ancestor('null:', 'null:'))
 
688
        self.assertEqual(True, graph.is_ancestor('null:', 'rev1'))
 
689
        self.assertEqual(False, graph.is_ancestor('rev1', 'null:'))
 
690
        self.assertEqual(True, graph.is_ancestor('null:', 'rev4'))
 
691
        self.assertEqual(False, graph.is_ancestor('rev4', 'null:'))
 
692
        self.assertEqual(False, graph.is_ancestor('rev4', 'rev2b'))
 
693
        self.assertEqual(True, graph.is_ancestor('rev2b', 'rev4'))
 
694
        self.assertEqual(False, graph.is_ancestor('rev2b', 'rev3'))
 
695
        self.assertEqual(False, graph.is_ancestor('rev3', 'rev2b'))
 
696
        instrumented_provider = InstrumentedParentsProvider(graph)
 
697
        instrumented_graph = _mod_graph.Graph(instrumented_provider)
 
698
        instrumented_graph.is_ancestor('rev2a', 'rev2b')
 
699
        self.assertTrue('null:' not in instrumented_provider.calls)
 
700
 
 
701
    def test_is_ancestor_boundary(self):
 
702
        """Ensure that we avoid searching the whole graph.
 
703
        
 
704
        This requires searching through b as a common ancestor, so we
 
705
        can identify that e is common.
 
706
        """
 
707
        graph = self.make_graph(boundary)
 
708
        instrumented_provider = InstrumentedParentsProvider(graph)
 
709
        graph = _mod_graph.Graph(instrumented_provider)
 
710
        self.assertFalse(graph.is_ancestor('a', 'c'))
 
711
        self.assertTrue('null:' not in instrumented_provider.calls)
 
712
 
 
713
    def test_iter_ancestry(self):
 
714
        nodes = boundary.copy()
 
715
        nodes[NULL_REVISION] = ()
 
716
        graph = self.make_graph(nodes)
 
717
        expected = nodes.copy()
 
718
        expected.pop('a') # 'a' is not in the ancestry of 'c', all the
 
719
                          # other nodes are
 
720
        self.assertEqual(expected, dict(graph.iter_ancestry(['c'])))
 
721
        self.assertEqual(nodes, dict(graph.iter_ancestry(['a', 'c'])))
 
722
 
 
723
    def test_iter_ancestry_with_ghost(self):
 
724
        graph = self.make_graph(with_ghost)
 
725
        expected = with_ghost.copy()
 
726
        # 'a' is not in the ancestry of 'c', and 'g' is a ghost
 
727
        expected['g'] = None
 
728
        self.assertEqual(expected, dict(graph.iter_ancestry(['a', 'c'])))
 
729
        expected.pop('a') 
 
730
        self.assertEqual(expected, dict(graph.iter_ancestry(['c'])))
 
731
 
 
732
    def test_filter_candidate_lca(self):
 
733
        """Test filter_candidate_lca for a corner case
 
734
 
 
735
        This tests the case where we encounter the end of iteration for 'e'
 
736
        in the same pass as we discover that 'd' is an ancestor of 'e', and
 
737
        therefore 'e' can't be an lca.
 
738
 
 
739
        To compensate for different dict orderings on other Python
 
740
        implementations, we mirror 'd' and 'e' with 'b' and 'a'.
 
741
        """
 
742
        # This test is sensitive to the iteration order of dicts.  It will
 
743
        # pass incorrectly if 'e' and 'a' sort before 'c'
 
744
        #
 
745
        # NULL_REVISION
 
746
        #     / \
 
747
        #    a   e
 
748
        #    |   |
 
749
        #    b   d
 
750
        #     \ /
 
751
        #      c
 
752
        graph = self.make_graph({'c': ['b', 'd'], 'd': ['e'], 'b': ['a'],
 
753
                                 'a': [NULL_REVISION], 'e': [NULL_REVISION]})
 
754
        self.assertEqual(set(['c']), graph.heads(['a', 'c', 'e']))
 
755
 
 
756
    def test_heads_null(self):
 
757
        graph = self.make_graph(ancestry_1)
 
758
        self.assertEqual(set(['null:']), graph.heads(['null:']))
 
759
        self.assertEqual(set(['rev1']), graph.heads(['null:', 'rev1']))
 
760
        self.assertEqual(set(['rev1']), graph.heads(['rev1', 'null:']))
 
761
        self.assertEqual(set(['rev1']), graph.heads(set(['rev1', 'null:'])))
 
762
        self.assertEqual(set(['rev1']), graph.heads(('rev1', 'null:')))
 
763
 
 
764
    def test_heads_one(self):
 
765
        # A single node will always be a head
 
766
        graph = self.make_graph(ancestry_1)
 
767
        self.assertEqual(set(['null:']), graph.heads(['null:']))
 
768
        self.assertEqual(set(['rev1']), graph.heads(['rev1']))
 
769
        self.assertEqual(set(['rev2a']), graph.heads(['rev2a']))
 
770
        self.assertEqual(set(['rev2b']), graph.heads(['rev2b']))
 
771
        self.assertEqual(set(['rev3']), graph.heads(['rev3']))
 
772
        self.assertEqual(set(['rev4']), graph.heads(['rev4']))
 
773
 
 
774
    def test_heads_single(self):
 
775
        graph = self.make_graph(ancestry_1)
 
776
        self.assertEqual(set(['rev4']), graph.heads(['null:', 'rev4']))
 
777
        self.assertEqual(set(['rev2a']), graph.heads(['rev1', 'rev2a']))
 
778
        self.assertEqual(set(['rev2b']), graph.heads(['rev1', 'rev2b']))
 
779
        self.assertEqual(set(['rev3']), graph.heads(['rev1', 'rev3']))
 
780
        self.assertEqual(set(['rev4']), graph.heads(['rev1', 'rev4']))
 
781
        self.assertEqual(set(['rev4']), graph.heads(['rev2a', 'rev4']))
 
782
        self.assertEqual(set(['rev4']), graph.heads(['rev2b', 'rev4']))
 
783
        self.assertEqual(set(['rev4']), graph.heads(['rev3', 'rev4']))
 
784
 
 
785
    def test_heads_two_heads(self):
 
786
        graph = self.make_graph(ancestry_1)
 
787
        self.assertEqual(set(['rev2a', 'rev2b']),
 
788
                         graph.heads(['rev2a', 'rev2b']))
 
789
        self.assertEqual(set(['rev3', 'rev2b']),
 
790
                         graph.heads(['rev3', 'rev2b']))
 
791
 
 
792
    def test_heads_criss_cross(self):
 
793
        graph = self.make_graph(criss_cross)
 
794
        self.assertEqual(set(['rev2a']),
 
795
                         graph.heads(['rev2a', 'rev1']))
 
796
        self.assertEqual(set(['rev2b']),
 
797
                         graph.heads(['rev2b', 'rev1']))
 
798
        self.assertEqual(set(['rev3a']),
 
799
                         graph.heads(['rev3a', 'rev1']))
 
800
        self.assertEqual(set(['rev3b']),
 
801
                         graph.heads(['rev3b', 'rev1']))
 
802
        self.assertEqual(set(['rev2a', 'rev2b']),
 
803
                         graph.heads(['rev2a', 'rev2b']))
 
804
        self.assertEqual(set(['rev3a']),
 
805
                         graph.heads(['rev3a', 'rev2a']))
 
806
        self.assertEqual(set(['rev3a']),
 
807
                         graph.heads(['rev3a', 'rev2b']))
 
808
        self.assertEqual(set(['rev3a']),
 
809
                         graph.heads(['rev3a', 'rev2a', 'rev2b']))
 
810
        self.assertEqual(set(['rev3b']),
 
811
                         graph.heads(['rev3b', 'rev2a']))
 
812
        self.assertEqual(set(['rev3b']),
 
813
                         graph.heads(['rev3b', 'rev2b']))
 
814
        self.assertEqual(set(['rev3b']),
 
815
                         graph.heads(['rev3b', 'rev2a', 'rev2b']))
 
816
        self.assertEqual(set(['rev3a', 'rev3b']),
 
817
                         graph.heads(['rev3a', 'rev3b']))
 
818
        self.assertEqual(set(['rev3a', 'rev3b']),
 
819
                         graph.heads(['rev3a', 'rev3b', 'rev2a', 'rev2b']))
 
820
 
 
821
    def test_heads_shortcut(self):
 
822
        graph = self.make_graph(history_shortcut)
 
823
 
 
824
        self.assertEqual(set(['rev2a', 'rev2b', 'rev2c']),
 
825
                         graph.heads(['rev2a', 'rev2b', 'rev2c']))
 
826
        self.assertEqual(set(['rev3a', 'rev3b']),
 
827
                         graph.heads(['rev3a', 'rev3b']))
 
828
        self.assertEqual(set(['rev3a', 'rev3b']),
 
829
                         graph.heads(['rev2a', 'rev3a', 'rev3b']))
 
830
        self.assertEqual(set(['rev2a', 'rev3b']),
 
831
                         graph.heads(['rev2a', 'rev3b']))
 
832
        self.assertEqual(set(['rev2c', 'rev3a']),
 
833
                         graph.heads(['rev2c', 'rev3a']))
 
834
 
 
835
    def _run_heads_break_deeper(self, graph_dict, search):
 
836
        """Run heads on a graph-as-a-dict.
 
837
        
 
838
        If the search asks for the parents of 'deeper' the test will fail.
 
839
        """
 
840
        class stub(object):
 
841
            pass
 
842
        def get_parent_map(keys):
 
843
            result = {}
 
844
            for key in keys:
 
845
                if key == 'deeper':
 
846
                    self.fail('key deeper was accessed')
 
847
                result[key] = graph_dict[key]
 
848
            return result
 
849
        an_obj = stub()
 
850
        an_obj.get_parent_map = get_parent_map
 
851
        graph = _mod_graph.Graph(an_obj)
 
852
        return graph.heads(search)
 
853
 
 
854
    def test_heads_limits_search(self):
 
855
        # test that a heads query does not search all of history
 
856
        graph_dict = {
 
857
            'left':['common'],
 
858
            'right':['common'],
 
859
            'common':['deeper'],
 
860
        }
 
861
        self.assertEqual(set(['left', 'right']),
 
862
            self._run_heads_break_deeper(graph_dict, ['left', 'right']))
 
863
 
 
864
    def test_heads_limits_search_assymetric(self):
 
865
        # test that a heads query does not search all of history
 
866
        graph_dict = {
 
867
            'left':['midleft'],
 
868
            'midleft':['common'],
 
869
            'right':['common'],
 
870
            'common':['aftercommon'],
 
871
            'aftercommon':['deeper'],
 
872
        }
 
873
        self.assertEqual(set(['left', 'right']),
 
874
            self._run_heads_break_deeper(graph_dict, ['left', 'right']))
 
875
 
 
876
    def test_heads_limits_search_common_search_must_continue(self):
 
877
        # test that common nodes are still queried, preventing
 
878
        # all-the-way-to-origin behaviour in the following graph:
 
879
        graph_dict = {
 
880
            'h1':['shortcut', 'common1'],
 
881
            'h2':['common1'],
 
882
            'shortcut':['common2'],
 
883
            'common1':['common2'],
 
884
            'common2':['deeper'],
 
885
        }
 
886
        self.assertEqual(set(['h1', 'h2']),
 
887
            self._run_heads_break_deeper(graph_dict, ['h1', 'h2']))
 
888
 
 
889
    def test_breadth_first_search_start_ghosts(self):
 
890
        graph = self.make_graph({})
 
891
        # with_ghosts reports the ghosts
 
892
        search = graph._make_breadth_first_searcher(['a-ghost'])
 
893
        self.assertEqual((set(), set(['a-ghost'])), search.next_with_ghosts())
 
894
        self.assertRaises(StopIteration, search.next_with_ghosts)
 
895
        # next includes them
 
896
        search = graph._make_breadth_first_searcher(['a-ghost'])
 
897
        self.assertEqual(set(['a-ghost']), search.next())
 
898
        self.assertRaises(StopIteration, search.next)
 
899
 
 
900
    def test_breadth_first_search_deep_ghosts(self):
 
901
        graph = self.make_graph({
 
902
            'head':['present'],
 
903
            'present':['child', 'ghost'],
 
904
            'child':[],
 
905
            })
 
906
        # with_ghosts reports the ghosts
 
907
        search = graph._make_breadth_first_searcher(['head'])
 
908
        self.assertEqual((set(['head']), set()), search.next_with_ghosts())
 
909
        self.assertEqual((set(['present']), set()), search.next_with_ghosts())
 
910
        self.assertEqual((set(['child']), set(['ghost'])),
 
911
            search.next_with_ghosts())
 
912
        self.assertRaises(StopIteration, search.next_with_ghosts)
 
913
        # next includes them
 
914
        search = graph._make_breadth_first_searcher(['head'])
 
915
        self.assertEqual(set(['head']), search.next())
 
916
        self.assertEqual(set(['present']), search.next())
 
917
        self.assertEqual(set(['child', 'ghost']),
 
918
            search.next())
 
919
        self.assertRaises(StopIteration, search.next)
 
920
 
 
921
    def test_breadth_first_search_change_next_to_next_with_ghosts(self):
 
922
        # To make the API robust, we allow calling both next() and
 
923
        # next_with_ghosts() on the same searcher.
 
924
        graph = self.make_graph({
 
925
            'head':['present'],
 
926
            'present':['child', 'ghost'],
 
927
            'child':[],
 
928
            })
 
929
        # start with next_with_ghosts
 
930
        search = graph._make_breadth_first_searcher(['head'])
 
931
        self.assertEqual((set(['head']), set()), search.next_with_ghosts())
 
932
        self.assertEqual(set(['present']), search.next())
 
933
        self.assertEqual((set(['child']), set(['ghost'])),
 
934
            search.next_with_ghosts())
 
935
        self.assertRaises(StopIteration, search.next)
 
936
        # start with next
 
937
        search = graph._make_breadth_first_searcher(['head'])
 
938
        self.assertEqual(set(['head']), search.next())
 
939
        self.assertEqual((set(['present']), set()), search.next_with_ghosts())
 
940
        self.assertEqual(set(['child', 'ghost']),
 
941
            search.next())
 
942
        self.assertRaises(StopIteration, search.next_with_ghosts)
 
943
 
 
944
    def test_breadth_first_change_search(self):
 
945
        # Changing the search should work with both next and next_with_ghosts.
 
946
        graph = self.make_graph({
 
947
            'head':['present'],
 
948
            'present':['stopped'],
 
949
            'other':['other_2'],
 
950
            'other_2':[],
 
951
            })
 
952
        search = graph._make_breadth_first_searcher(['head'])
 
953
        self.assertEqual((set(['head']), set()), search.next_with_ghosts())
 
954
        self.assertEqual((set(['present']), set()), search.next_with_ghosts())
 
955
        self.assertEqual(set(['present']),
 
956
            search.stop_searching_any(['present']))
 
957
        self.assertEqual((set(['other']), set(['other_ghost'])),
 
958
            search.start_searching(['other', 'other_ghost']))
 
959
        self.assertEqual((set(['other_2']), set()), search.next_with_ghosts())
 
960
        self.assertRaises(StopIteration, search.next_with_ghosts)
 
961
        # next includes them
 
962
        search = graph._make_breadth_first_searcher(['head'])
 
963
        self.assertEqual(set(['head']), search.next())
 
964
        self.assertEqual(set(['present']), search.next())
 
965
        self.assertEqual(set(['present']),
 
966
            search.stop_searching_any(['present']))
 
967
        search.start_searching(['other', 'other_ghost'])
 
968
        self.assertEqual(set(['other_2']), search.next())
 
969
        self.assertRaises(StopIteration, search.next)
 
970
 
 
971
    def assertSeenAndResult(self, instructions, search, next):
 
972
        """Check the results of .seen and get_result() for a seach.
 
973
 
 
974
        :param instructions: A list of tuples:
 
975
            (seen, recipe, included_keys, starts, stops).
 
976
            seen, recipe and included_keys are results to check on the search
 
977
            and the searches get_result(). starts and stops are parameters to
 
978
            pass to start_searching and stop_searching_any during each
 
979
            iteration, if they are not None.
 
980
        :param search: The search to use.
 
981
        :param next: A callable to advance the search.
 
982
        """
 
983
        for seen, recipe, included_keys, starts, stops in instructions:
 
984
            next()
 
985
            if starts is not None:
 
986
                search.start_searching(starts)
 
987
            if stops is not None:
 
988
                search.stop_searching_any(stops)
 
989
            result = search.get_result()
 
990
            self.assertEqual(recipe, result.get_recipe())
 
991
            self.assertEqual(set(included_keys), result.get_keys())
 
992
            self.assertEqual(seen, search.seen)
 
993
 
 
994
    def test_breadth_first_get_result_excludes_current_pending(self):
 
995
        graph = self.make_graph({
 
996
            'head':['child'],
 
997
            'child':[NULL_REVISION],
 
998
            NULL_REVISION:[],
 
999
            })
 
1000
        search = graph._make_breadth_first_searcher(['head'])
 
1001
        # At the start, nothing has been seen, to its all excluded:
 
1002
        result = search.get_result()
 
1003
        self.assertEqual((set(['head']), set(['head']), 0),
 
1004
            result.get_recipe())
 
1005
        self.assertEqual(set(), result.get_keys())
 
1006
        self.assertEqual(set(), search.seen)
 
1007
        # using next:
 
1008
        expected = [
 
1009
            (set(['head']), (set(['head']), set(['child']), 1),
 
1010
             ['head'], None, None),
 
1011
            (set(['head', 'child']), (set(['head']), set([NULL_REVISION]), 2),
 
1012
             ['head', 'child'], None, None),
 
1013
            (set(['head', 'child', NULL_REVISION]), (set(['head']), set(), 3),
 
1014
             ['head', 'child', NULL_REVISION], None, None),
 
1015
            ]
 
1016
        self.assertSeenAndResult(expected, search, search.next)
 
1017
        # using next_with_ghosts:
 
1018
        search = graph._make_breadth_first_searcher(['head'])
 
1019
        self.assertSeenAndResult(expected, search, search.next_with_ghosts)
 
1020
 
 
1021
    def test_breadth_first_get_result_starts_stops(self):
 
1022
        graph = self.make_graph({
 
1023
            'head':['child'],
 
1024
            'child':[NULL_REVISION],
 
1025
            'otherhead':['otherchild'],
 
1026
            'otherchild':['excluded'],
 
1027
            'excluded':[NULL_REVISION],
 
1028
            NULL_REVISION:[]
 
1029
            })
 
1030
        search = graph._make_breadth_first_searcher([])
 
1031
        # Starting with nothing and adding a search works:
 
1032
        search.start_searching(['head'])
 
1033
        # head has been seen:
 
1034
        result = search.get_result()
 
1035
        self.assertEqual((set(['head']), set(['child']), 1),
 
1036
            result.get_recipe())
 
1037
        self.assertEqual(set(['head']), result.get_keys())
 
1038
        self.assertEqual(set(['head']), search.seen)
 
1039
        # using next:
 
1040
        expected = [
 
1041
            # stop at child, and start a new search at otherhead:
 
1042
            # - otherhead counts as seen immediately when start_searching is
 
1043
            # called.
 
1044
            (set(['head', 'child', 'otherhead']),
 
1045
             (set(['head', 'otherhead']), set(['child', 'otherchild']), 2),
 
1046
             ['head', 'otherhead'], ['otherhead'], ['child']),
 
1047
            (set(['head', 'child', 'otherhead', 'otherchild']),
 
1048
             (set(['head', 'otherhead']), set(['child', 'excluded']), 3),
 
1049
             ['head', 'otherhead', 'otherchild'], None, None),
 
1050
            # stop searching excluded now
 
1051
            (set(['head', 'child', 'otherhead', 'otherchild', 'excluded']),
 
1052
             (set(['head', 'otherhead']), set(['child', 'excluded']), 3),
 
1053
             ['head', 'otherhead', 'otherchild'], None, ['excluded']),
 
1054
            ]
 
1055
        self.assertSeenAndResult(expected, search, search.next)
 
1056
        # using next_with_ghosts:
 
1057
        search = graph._make_breadth_first_searcher([])
 
1058
        search.start_searching(['head'])
 
1059
        self.assertSeenAndResult(expected, search, search.next_with_ghosts)
 
1060
 
 
1061
    def test_breadth_first_stop_searching_not_queried(self):
 
1062
        # A client should be able to say 'stop node X' even if X has not been
 
1063
        # returned to the client.
 
1064
        graph = self.make_graph({
 
1065
            'head':['child', 'ghost1'],
 
1066
            'child':[NULL_REVISION],
 
1067
            NULL_REVISION:[],
 
1068
            })
 
1069
        search = graph._make_breadth_first_searcher(['head'])
 
1070
        expected = [
 
1071
            # NULL_REVISION and ghost1 have not been returned
 
1072
            (set(['head']), (set(['head']), set(['child', 'ghost1']), 1),
 
1073
             ['head'], None, [NULL_REVISION, 'ghost1']),
 
1074
            # ghost1 has been returned, NULL_REVISION is to be returned in the
 
1075
            # next iteration.
 
1076
            (set(['head', 'child', 'ghost1']),
 
1077
             (set(['head']), set(['ghost1', NULL_REVISION]), 2),
 
1078
             ['head', 'child'], None, [NULL_REVISION, 'ghost1']),
 
1079
            ]
 
1080
        self.assertSeenAndResult(expected, search, search.next)
 
1081
        # using next_with_ghosts:
 
1082
        search = graph._make_breadth_first_searcher(['head'])
 
1083
        self.assertSeenAndResult(expected, search, search.next_with_ghosts)
 
1084
 
 
1085
    def test_breadth_first_stop_searching_late(self):
 
1086
        # A client should be able to say 'stop node X' and have it excluded
 
1087
        # from the result even if X was seen in an older iteration of the
 
1088
        # search.
 
1089
        graph = self.make_graph({
 
1090
            'head':['middle'],
 
1091
            'middle':['child'],
 
1092
            'child':[NULL_REVISION],
 
1093
            NULL_REVISION:[],
 
1094
            })
 
1095
        search = graph._make_breadth_first_searcher(['head'])
 
1096
        expected = [
 
1097
            (set(['head']), (set(['head']), set(['middle']), 1),
 
1098
             ['head'], None, None),
 
1099
            (set(['head', 'middle']), (set(['head']), set(['child']), 2),
 
1100
             ['head', 'middle'], None, None),
 
1101
            # 'middle' came from the previous iteration, but we don't stop
 
1102
            # searching it until *after* advancing the searcher.
 
1103
            (set(['head', 'middle', 'child']),
 
1104
             (set(['head']), set(['middle', 'child']), 1),
 
1105
             ['head'], None, ['middle', 'child']),
 
1106
            ]
 
1107
        self.assertSeenAndResult(expected, search, search.next)
 
1108
        # using next_with_ghosts:
 
1109
        search = graph._make_breadth_first_searcher(['head'])
 
1110
        self.assertSeenAndResult(expected, search, search.next_with_ghosts)
 
1111
 
 
1112
    def test_breadth_first_get_result_ghosts_are_excluded(self):
 
1113
        graph = self.make_graph({
 
1114
            'head':['child', 'ghost'],
 
1115
            'child':[NULL_REVISION],
 
1116
            NULL_REVISION:[],
 
1117
            })
 
1118
        search = graph._make_breadth_first_searcher(['head'])
 
1119
        # using next:
 
1120
        expected = [
 
1121
            (set(['head']),
 
1122
             (set(['head']), set(['ghost', 'child']), 1),
 
1123
             ['head'], None, None),
 
1124
            (set(['head', 'child', 'ghost']),
 
1125
             (set(['head']), set([NULL_REVISION, 'ghost']), 2),
 
1126
             ['head', 'child'], None, None),
 
1127
            ]
 
1128
        self.assertSeenAndResult(expected, search, search.next)
 
1129
        # using next_with_ghosts:
 
1130
        search = graph._make_breadth_first_searcher(['head'])
 
1131
        self.assertSeenAndResult(expected, search, search.next_with_ghosts)
 
1132
 
 
1133
    def test_breadth_first_get_result_starting_a_ghost_ghost_is_excluded(self):
 
1134
        graph = self.make_graph({
 
1135
            'head':['child'],
 
1136
            'child':[NULL_REVISION],
 
1137
            NULL_REVISION:[],
 
1138
            })
 
1139
        search = graph._make_breadth_first_searcher(['head'])
 
1140
        # using next:
 
1141
        expected = [
 
1142
            (set(['head', 'ghost']),
 
1143
             (set(['head', 'ghost']), set(['child', 'ghost']), 1),
 
1144
             ['head'], ['ghost'], None),
 
1145
            (set(['head', 'child', 'ghost']),
 
1146
             (set(['head', 'ghost']), set([NULL_REVISION, 'ghost']), 2),
 
1147
             ['head', 'child'], None, None),
 
1148
            ]
 
1149
        self.assertSeenAndResult(expected, search, search.next)
 
1150
        # using next_with_ghosts:
 
1151
        search = graph._make_breadth_first_searcher(['head'])
 
1152
        self.assertSeenAndResult(expected, search, search.next_with_ghosts)
 
1153
 
 
1154
    def test_breadth_first_revision_count_includes_NULL_REVISION(self):
 
1155
        graph = self.make_graph({
 
1156
            'head':[NULL_REVISION],
 
1157
            NULL_REVISION:[],
 
1158
            })
 
1159
        search = graph._make_breadth_first_searcher(['head'])
 
1160
        # using next:
 
1161
        expected = [
 
1162
            (set(['head']),
 
1163
             (set(['head']), set([NULL_REVISION]), 1),
 
1164
             ['head'], None, None),
 
1165
            (set(['head', NULL_REVISION]),
 
1166
             (set(['head']), set([]), 2),
 
1167
             ['head', NULL_REVISION], None, None),
 
1168
            ]
 
1169
        self.assertSeenAndResult(expected, search, search.next)
 
1170
        # using next_with_ghosts:
 
1171
        search = graph._make_breadth_first_searcher(['head'])
 
1172
        self.assertSeenAndResult(expected, search, search.next_with_ghosts)
 
1173
 
 
1174
    def test_breadth_first_search_get_result_after_StopIteration(self):
 
1175
        # StopIteration should not invalid anything..
 
1176
        graph = self.make_graph({
 
1177
            'head':[NULL_REVISION],
 
1178
            NULL_REVISION:[],
 
1179
            })
 
1180
        search = graph._make_breadth_first_searcher(['head'])
 
1181
        # using next:
 
1182
        expected = [
 
1183
            (set(['head']),
 
1184
             (set(['head']), set([NULL_REVISION]), 1),
 
1185
             ['head'], None, None),
 
1186
            (set(['head', 'ghost', NULL_REVISION]),
 
1187
             (set(['head', 'ghost']), set(['ghost']), 2),
 
1188
             ['head', NULL_REVISION], ['ghost'], None),
 
1189
            ]
 
1190
        self.assertSeenAndResult(expected, search, search.next)
 
1191
        self.assertRaises(StopIteration, search.next)
 
1192
        self.assertEqual(set(['head', 'ghost', NULL_REVISION]), search.seen)
 
1193
        result = search.get_result()
 
1194
        self.assertEqual((set(['ghost', 'head']), set(['ghost']), 2),
 
1195
            result.get_recipe())
 
1196
        self.assertEqual(set(['head', NULL_REVISION]), result.get_keys())
 
1197
        # using next_with_ghosts:
 
1198
        search = graph._make_breadth_first_searcher(['head'])
 
1199
        self.assertSeenAndResult(expected, search, search.next_with_ghosts)
 
1200
        self.assertRaises(StopIteration, search.next)
 
1201
        self.assertEqual(set(['head', 'ghost', NULL_REVISION]), search.seen)
 
1202
        result = search.get_result()
 
1203
        self.assertEqual((set(['ghost', 'head']), set(['ghost']), 2),
 
1204
            result.get_recipe())
 
1205
        self.assertEqual(set(['head', NULL_REVISION]), result.get_keys())
 
1206
 
 
1207
 
 
1208
class TestFindUniqueAncestors(TestGraphBase):
 
1209
 
 
1210
    def assertFindUniqueAncestors(self, graph, expected, node, common):
 
1211
        actual = graph.find_unique_ancestors(node, common)
 
1212
        self.assertEqual(expected, sorted(actual))
 
1213
 
 
1214
    def test_empty_set(self):
 
1215
        graph = self.make_graph(ancestry_1)
 
1216
        self.assertFindUniqueAncestors(graph, [], 'rev1', ['rev1'])
 
1217
        self.assertFindUniqueAncestors(graph, [], 'rev2b', ['rev2b'])
 
1218
        self.assertFindUniqueAncestors(graph, [], 'rev3', ['rev1', 'rev3'])
 
1219
 
 
1220
    def test_single_node(self):
 
1221
        graph = self.make_graph(ancestry_1)
 
1222
        self.assertFindUniqueAncestors(graph, ['rev2a'], 'rev2a', ['rev1'])
 
1223
        self.assertFindUniqueAncestors(graph, ['rev2b'], 'rev2b', ['rev1'])
 
1224
        self.assertFindUniqueAncestors(graph, ['rev3'], 'rev3', ['rev2a'])
 
1225
 
 
1226
    def test_minimal_ancestry(self):
 
1227
        graph = self.make_breaking_graph(extended_history_shortcut,
 
1228
                                         [NULL_REVISION, 'a', 'b'])
 
1229
        self.assertFindUniqueAncestors(graph, ['e'], 'e', ['d'])
 
1230
 
 
1231
        graph = self.make_breaking_graph(extended_history_shortcut,
 
1232
                                         ['b'])
 
1233
        self.assertFindUniqueAncestors(graph, ['f'], 'f', ['a', 'd'])
 
1234
 
 
1235
        graph = self.make_breaking_graph(complex_shortcut,
 
1236
                                         ['a', 'b'])
 
1237
        self.assertFindUniqueAncestors(graph, ['h'], 'h', ['i'])
 
1238
        self.assertFindUniqueAncestors(graph, ['e', 'g', 'i'], 'i', ['h'])
 
1239
        self.assertFindUniqueAncestors(graph, ['h'], 'h', ['g'])
 
1240
        self.assertFindUniqueAncestors(graph, ['h'], 'h', ['j'])
 
1241
 
 
1242
    def test_in_ancestry(self):
 
1243
        graph = self.make_graph(ancestry_1)
 
1244
        self.assertFindUniqueAncestors(graph, [], 'rev1', ['rev3'])
 
1245
        self.assertFindUniqueAncestors(graph, [], 'rev2b', ['rev4'])
 
1246
 
 
1247
    def test_multiple_revisions(self):
 
1248
        graph = self.make_graph(ancestry_1)
 
1249
        self.assertFindUniqueAncestors(graph,
 
1250
            ['rev4'], 'rev4', ['rev3', 'rev2b'])
 
1251
        self.assertFindUniqueAncestors(graph,
 
1252
            ['rev2a', 'rev3', 'rev4'], 'rev4', ['rev2b'])
 
1253
 
 
1254
    def test_complex_shortcut(self):
 
1255
        graph = self.make_graph(complex_shortcut)
 
1256
        self.assertFindUniqueAncestors(graph,
 
1257
            ['h', 'n'], 'n', ['m'])
 
1258
        self.assertFindUniqueAncestors(graph,
 
1259
            ['e', 'i', 'm'], 'm', ['n'])
 
1260
 
 
1261
    def test_complex_shortcut2(self):
 
1262
        graph = self.make_graph(complex_shortcut2)
 
1263
        self.assertFindUniqueAncestors(graph,
 
1264
            ['j', 'u'], 'u', ['t'])
 
1265
        self.assertFindUniqueAncestors(graph,
 
1266
            ['t'], 't', ['u'])
 
1267
 
 
1268
    def test_multiple_interesting_unique(self):
 
1269
        graph = self.make_graph(multiple_interesting_unique)
 
1270
        self.assertFindUniqueAncestors(graph,
 
1271
            ['j', 'y'], 'y', ['z'])
 
1272
        self.assertFindUniqueAncestors(graph,
 
1273
            ['p', 'z'], 'z', ['y'])
 
1274
 
 
1275
    def test_racing_shortcuts(self):
 
1276
        graph = self.make_graph(racing_shortcuts)
 
1277
        self.assertFindUniqueAncestors(graph,
 
1278
            ['p', 'q', 'z'], 'z', ['y'])
 
1279
        self.assertFindUniqueAncestors(graph,
 
1280
            ['h', 'i', 'j', 'y'], 'j', ['z'])
 
1281
 
 
1282
 
 
1283
class TestGraphFindDistanceToNull(TestGraphBase):
 
1284
    """Test an api that should be able to compute a revno"""
 
1285
 
 
1286
    def assertFindDistance(self, revno, graph, target_id, known_ids):
 
1287
        """Assert the output of Graph.find_distance_to_null()"""
 
1288
        actual = graph.find_distance_to_null(target_id, known_ids)
 
1289
        self.assertEqual(revno, actual)
 
1290
 
 
1291
    def test_nothing_known(self):
 
1292
        graph = self.make_graph(ancestry_1)
 
1293
        self.assertFindDistance(0, graph, NULL_REVISION, [])
 
1294
        self.assertFindDistance(1, graph, 'rev1', [])
 
1295
        self.assertFindDistance(2, graph, 'rev2a', [])
 
1296
        self.assertFindDistance(2, graph, 'rev2b', [])
 
1297
        self.assertFindDistance(3, graph, 'rev3', [])
 
1298
        self.assertFindDistance(4, graph, 'rev4', [])
 
1299
 
 
1300
    def test_rev_is_ghost(self):
 
1301
        graph = self.make_graph(ancestry_1)
 
1302
        e = self.assertRaises(errors.GhostRevisionsHaveNoRevno,
 
1303
                              graph.find_distance_to_null, 'rev_missing', [])
 
1304
        self.assertEqual('rev_missing', e.revision_id)
 
1305
        self.assertEqual('rev_missing', e.ghost_revision_id)
 
1306
 
 
1307
    def test_ancestor_is_ghost(self):
 
1308
        graph = self.make_graph({'rev':['parent']})
 
1309
        e = self.assertRaises(errors.GhostRevisionsHaveNoRevno,
 
1310
                              graph.find_distance_to_null, 'rev', [])
 
1311
        self.assertEqual('rev', e.revision_id)
 
1312
        self.assertEqual('parent', e.ghost_revision_id)
 
1313
 
 
1314
    def test_known_in_ancestry(self):
 
1315
        graph = self.make_graph(ancestry_1)
 
1316
        self.assertFindDistance(2, graph, 'rev2a', [('rev1', 1)])
 
1317
        self.assertFindDistance(3, graph, 'rev3', [('rev2a', 2)])
 
1318
 
 
1319
    def test_known_in_ancestry_limits(self):
 
1320
        graph = self.make_breaking_graph(ancestry_1, ['rev1'])
 
1321
        self.assertFindDistance(4, graph, 'rev4', [('rev3', 3)])
 
1322
 
 
1323
    def test_target_is_ancestor(self):
 
1324
        graph = self.make_graph(ancestry_1)
 
1325
        self.assertFindDistance(2, graph, 'rev2a', [('rev3', 3)])
 
1326
 
 
1327
    def test_target_is_ancestor_limits(self):
 
1328
        """We shouldn't search all history if we run into ourselves"""
 
1329
        graph = self.make_breaking_graph(ancestry_1, ['rev1'])
 
1330
        self.assertFindDistance(3, graph, 'rev3', [('rev4', 4)])
 
1331
 
 
1332
    def test_target_parallel_to_known_limits(self):
 
1333
        # Even though the known revision isn't part of the other ancestry, they
 
1334
        # eventually converge
 
1335
        graph = self.make_breaking_graph(with_tail, ['a'])
 
1336
        self.assertFindDistance(6, graph, 'f', [('g', 6)])
 
1337
        self.assertFindDistance(7, graph, 'h', [('g', 6)])
 
1338
        self.assertFindDistance(8, graph, 'i', [('g', 6)])
 
1339
        self.assertFindDistance(6, graph, 'g', [('i', 8)])
 
1340
 
 
1341
 
 
1342
class TestFindMergeOrder(TestGraphBase):
 
1343
 
 
1344
    def assertMergeOrder(self, expected, graph, tip, base_revisions):
 
1345
        self.assertEqual(expected, graph.find_merge_order(tip, base_revisions))
 
1346
 
 
1347
    def test_parents(self):
 
1348
        graph = self.make_graph(ancestry_1)
 
1349
        self.assertMergeOrder(['rev3', 'rev2b'], graph, 'rev4',
 
1350
                                                        ['rev3', 'rev2b'])
 
1351
        self.assertMergeOrder(['rev3', 'rev2b'], graph, 'rev4',
 
1352
                                                        ['rev2b', 'rev3'])
 
1353
 
 
1354
    def test_ancestors(self):
 
1355
        graph = self.make_graph(ancestry_1)
 
1356
        self.assertMergeOrder(['rev1', 'rev2b'], graph, 'rev4',
 
1357
                                                        ['rev1', 'rev2b'])
 
1358
        self.assertMergeOrder(['rev1', 'rev2b'], graph, 'rev4',
 
1359
                                                        ['rev2b', 'rev1'])
 
1360
 
 
1361
    def test_shortcut_one_ancestor(self):
 
1362
        # When we have enough info, we can stop searching
 
1363
        graph = self.make_breaking_graph(ancestry_1, ['rev3', 'rev2b', 'rev4'])
 
1364
        # Single ancestors shortcut right away
 
1365
        self.assertMergeOrder(['rev3'], graph, 'rev4', ['rev3'])
 
1366
 
 
1367
    def test_shortcut_after_one_ancestor(self):
 
1368
        graph = self.make_breaking_graph(ancestry_1, ['rev2a', 'rev2b'])
 
1369
        self.assertMergeOrder(['rev3', 'rev1'], graph, 'rev4', ['rev1', 'rev3'])
 
1370
 
 
1371
 
 
1372
class TestCachingParentsProvider(tests.TestCase):
 
1373
 
 
1374
    def setUp(self):
 
1375
        super(TestCachingParentsProvider, self).setUp()
 
1376
        dict_pp = _mod_graph.DictParentsProvider({'a':('b',)})
 
1377
        self.inst_pp = InstrumentedParentsProvider(dict_pp)
 
1378
        self.caching_pp = _mod_graph.CachingParentsProvider(self.inst_pp)
 
1379
 
 
1380
    def test_get_parent_map(self):
 
1381
        """Requesting the same revision should be returned from cache"""
 
1382
        self.assertEqual({}, self.caching_pp._cache)
 
1383
        self.assertEqual({'a':('b',)}, self.caching_pp.get_parent_map(['a']))
 
1384
        self.assertEqual(['a'], self.inst_pp.calls)
 
1385
        self.assertEqual({'a':('b',)}, self.caching_pp.get_parent_map(['a']))
 
1386
        # No new call, as it should have been returned from the cache
 
1387
        self.assertEqual(['a'], self.inst_pp.calls)
 
1388
        self.assertEqual({'a':('b',)}, self.caching_pp._cache)
 
1389
 
 
1390
    def test_get_parent_map_not_present(self):
 
1391
        """The cache should also track when a revision doesn't exist"""
 
1392
        self.assertEqual({}, self.caching_pp.get_parent_map(['b']))
 
1393
        self.assertEqual(['b'], self.inst_pp.calls)
 
1394
        self.assertEqual({}, self.caching_pp.get_parent_map(['b']))
 
1395
        # No new calls
 
1396
        self.assertEqual(['b'], self.inst_pp.calls)
 
1397
        self.assertEqual({'b':None}, self.caching_pp._cache)
 
1398
 
 
1399
    def test_get_parent_map_mixed(self):
 
1400
        """Anything that can be returned from cache, should be"""
 
1401
        self.assertEqual({}, self.caching_pp.get_parent_map(['b']))
 
1402
        self.assertEqual(['b'], self.inst_pp.calls)
 
1403
        self.assertEqual({'a':('b',)},
 
1404
                         self.caching_pp.get_parent_map(['a', 'b']))
 
1405
        self.assertEqual(['b', 'a'], self.inst_pp.calls)
 
1406
 
 
1407
    def test_get_parent_map_repeated(self):
 
1408
        """Asking for the same parent 2x will only forward 1 request."""
 
1409
        self.assertEqual({'a':('b',)},
 
1410
                         self.caching_pp.get_parent_map(['b', 'a', 'b']))
 
1411
        # Use sorted because we don't care about the order, just that each is
 
1412
        # only present 1 time.
 
1413
        self.assertEqual(['a', 'b'], sorted(self.inst_pp.calls))
 
1414
 
 
1415
 
 
1416
class TestCollapseLinearRegions(tests.TestCase):
 
1417
 
 
1418
    def assertCollapsed(self, collapsed, original):
 
1419
        self.assertEqual(collapsed,
 
1420
                         _mod_graph.collapse_linear_regions(original))
 
1421
 
 
1422
    def test_collapse_nothing(self):
 
1423
        d = {1:[2, 3], 2:[], 3:[]}
 
1424
        self.assertCollapsed(d, d)
 
1425
        d = {1:[2], 2:[3, 4], 3:[5], 4:[5], 5:[]}
 
1426
        self.assertCollapsed(d, d)
 
1427
 
 
1428
    def test_collapse_chain(self):
 
1429
        # Any time we have a linear chain, we should be able to collapse
 
1430
        d = {1:[2], 2:[3], 3:[4], 4:[5], 5:[]}
 
1431
        self.assertCollapsed({1:[5], 5:[]}, d)
 
1432
        d = {5:[4], 4:[3], 3:[2], 2:[1], 1:[]}
 
1433
        self.assertCollapsed({5:[1], 1:[]}, d)
 
1434
        d = {5:[3], 3:[4], 4:[1], 1:[2], 2:[]}
 
1435
        self.assertCollapsed({5:[2], 2:[]}, d)
 
1436
 
 
1437
    def test_collapse_with_multiple_children(self):
 
1438
        #    7
 
1439
        #    |
 
1440
        #    6
 
1441
        #   / \
 
1442
        #  4   5
 
1443
        #  |   |
 
1444
        #  2   3
 
1445
        #   \ /
 
1446
        #    1
 
1447
        #
 
1448
        # 4 and 5 cannot be removed because 6 has 2 children
 
1449
        # 2 and 3 cannot be removed because 1 has 2 parents
 
1450
        d = {1:[2, 3], 2:[4], 4:[6], 3:[5], 5:[6], 6:[7], 7:[]}
 
1451
        self.assertCollapsed(d, d)