/brz/remove-bazaar

To get this branch, use:
bzr branch http://gegoxaren.bato24.eu/bzr/brz/remove-bazaar
2490.2.5 by Aaron Bentley
Use GraphWalker.unique_ancestor to determine merge base
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# Copyright (C) 2007 Canonical Ltd
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#
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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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#
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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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#
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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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2490.2.28 by Aaron Bentley
Fix handling of null revision
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from bzrlib import (
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    errors,
2653.2.1 by Aaron Bentley
Implement Graph.is_ancestor
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    graph as _mod_graph,
3099.3.3 by John Arbash Meinel
Deprecate get_parents() in favor of get_parent_map()
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    symbol_versioning,
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
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    tests,
2490.2.28 by Aaron Bentley
Fix handling of null revision
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    )
2490.2.1 by Aaron Bentley
Start work on GraphWalker
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from bzrlib.revision import NULL_REVISION
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from bzrlib.tests import TestCaseWithMemoryTransport
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2490.2.25 by Aaron Bentley
Update from review
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# Ancestry 1:
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#
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#  NULL_REVISION
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#       |
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#     rev1
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#      /\
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#  rev2a rev2b
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#     |    |
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#   rev3  /
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#     |  /
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#   rev4
2490.2.2 by Aaron Bentley
add minimal-common-ancestor calculation
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ancestry_1 = {'rev1': [NULL_REVISION], 'rev2a': ['rev1'], 'rev2b': ['rev1'],
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              'rev3': ['rev2a'], 'rev4': ['rev3', 'rev2b']}
2490.2.25 by Aaron Bentley
Update from review
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# Ancestry 2:
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#
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#  NULL_REVISION
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#    /    \
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# rev1a  rev1b
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#   |
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# rev2a
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#   |
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# rev3a
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#   |
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# rev4a
2490.2.4 by Aaron Bentley
More tests for unique common ancestor
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ancestry_2 = {'rev1a': [NULL_REVISION], 'rev2a': ['rev1a'],
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              'rev1b': [NULL_REVISION], 'rev3a': ['rev2a'], 'rev4a': ['rev3a']}
2490.2.2 by Aaron Bentley
add minimal-common-ancestor calculation
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2490.2.25 by Aaron Bentley
Update from review
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# Criss cross ancestry
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#
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#     NULL_REVISION
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#         |
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#        rev1
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#        /  \
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#    rev2a  rev2b
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#       |\  /|
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#       |  X |
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#       |/  \|
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#    rev3a  rev3b
2490.2.3 by Aaron Bentley
Implement new merge base picker
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criss_cross = {'rev1': [NULL_REVISION], 'rev2a': ['rev1'], 'rev2b': ['rev1'],
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               'rev3a': ['rev2a', 'rev2b'], 'rev3b': ['rev2b', 'rev2a']}
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2490.2.25 by Aaron Bentley
Update from review
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# Criss-cross 2
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#
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#  NULL_REVISION
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#    /   \
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# rev1a  rev1b
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#   |\   /|
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#   | \ / |
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#   |  X  |
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#   | / \ |
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#   |/   \|
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# rev2a  rev2b
2490.2.4 by Aaron Bentley
More tests for unique common ancestor
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criss_cross2 = {'rev1a': [NULL_REVISION], 'rev1b': [NULL_REVISION],
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                'rev2a': ['rev1a', 'rev1b'], 'rev2b': ['rev1b', 'rev1a']}
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2490.2.25 by Aaron Bentley
Update from review
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# Mainline:
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#
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#  NULL_REVISION
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#       |
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#      rev1
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#      /  \
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#      | rev2b
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#      |  /
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#     rev2a
2490.2.6 by Aaron Bentley
Use new common-ancestor code everywhere
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mainline = {'rev1': [NULL_REVISION], 'rev2a': ['rev1', 'rev2b'],
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            'rev2b': ['rev1']}
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2490.2.25 by Aaron Bentley
Update from review
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# feature branch:
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#
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#  NULL_REVISION
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#       |
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#      rev1
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#       |
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#     rev2b
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#       |
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#     rev3b
2490.2.6 by Aaron Bentley
Use new common-ancestor code everywhere
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feature_branch = {'rev1': [NULL_REVISION],
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                  'rev2b': ['rev1'], 'rev3b': ['rev2b']}
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2490.2.25 by Aaron Bentley
Update from review
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# History shortcut
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#  NULL_REVISION
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#       |
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#     rev1------
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#     /  \      \
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#  rev2a rev2b rev2c
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#    |  /   \   /
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
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#  rev3a    rev3b
2490.2.9 by Aaron Bentley
Fix minimal common ancestor algorithm for non-minimal perhipheral ancestors
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history_shortcut = {'rev1': [NULL_REVISION], 'rev2a': ['rev1'],
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                    'rev2b': ['rev1'], 'rev2c': ['rev1'],
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                    'rev3a': ['rev2a', 'rev2b'], 'rev3b': ['rev2b', 'rev2c']}
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3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
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# Extended history shortcut
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#  NULL_REVISION
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#       |
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#       a
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#       |\
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#       b |
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#       | |
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#       c |
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#       | |
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#       d |
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#       |\|
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#       e f
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extended_history_shortcut = {'a': [NULL_REVISION],
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                             'b': ['a'],
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                             'c': ['b'],
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                             'd': ['c'],
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                             'e': ['d'],
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                             'f': ['a', 'd'],
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                            }
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# Double shortcut
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# Both sides will see 'A' first, even though it is actually a decendent of a
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# different common revision.
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#
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#  NULL_REVISION
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#       |
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#       a
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#      /|\
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#     / b \
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#    /  |  \
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#   |   c   |
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#   |  / \  |
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#   | d   e |
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#   |/     \|
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#   f       g
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double_shortcut = {'a':[NULL_REVISION], 'b':['a'], 'c':['b'],
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                   'd':['c'], 'e':['c'], 'f':['a', 'd'],
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                   'g':['a', 'e']}
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# Complex shortcut
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# This has a failure mode in that a shortcut will find some nodes in common,
3377.3.37 by John Arbash Meinel
Ian's first review comments.
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# but the common searcher won't have time to find that one branch is actually
3377.3.1 by John Arbash Meinel
Bring in some of the changes from graph_update and graph_optimization
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# in common. The extra nodes at the beginning are because we want to avoid
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
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# walking off the graph. Specifically, node G should be considered common, but
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# is likely to be seen by M long before the common searcher finds it.
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#
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# NULL_REVISION
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#     |
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#     a
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#     |
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#     b
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#     |
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#     c
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#     |
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#     d
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#     |\
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#     e f
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#     | |\
3377.3.1 by John Arbash Meinel
Bring in some of the changes from graph_update and graph_optimization
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#     | g h
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#     |/| |
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#     i j |
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#     | | |
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#     | k |
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#     | | |
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#     | l |
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#     |/|/
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#     m n
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complex_shortcut = {'a':[NULL_REVISION], 'b':['a'], 'c':['b'], 'd':['c'],
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                    'e':['d'], 'f':['d'], 'g':['f'], 'h':['f'],
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                    'i':['e', 'g'], 'j':['g'], 'k':['j'],
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                    'l':['k'], 'm':['i', 'l'], 'n':['l', 'h']}
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# NULL_REVISION
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#     |
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#     a
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#     |
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#     b
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#     |
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#     c
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#     |
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#     d
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#     |\
3377.3.13 by John Arbash Meinel
Change _search_for_extra_common slightly.
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#     e |
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#     | |
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#     f |
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#     | |
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#     g h
3377.3.1 by John Arbash Meinel
Bring in some of the changes from graph_update and graph_optimization
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#     | |\
3377.3.13 by John Arbash Meinel
Change _search_for_extra_common slightly.
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#     i | j
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
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#     |\| |
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#     | k |
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#     | | |
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#     | l |
3377.3.13 by John Arbash Meinel
Change _search_for_extra_common slightly.
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#     | | |
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#     | m |
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#     | | |
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#     | n |
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#     | | |
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#     | o |
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#     | | |
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#     | p |
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#     | | |
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#     | q |
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#     | | |
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#     | r |
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#     | | |
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#     | s |
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#     | | |
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
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#     |/|/
3377.3.13 by John Arbash Meinel
Change _search_for_extra_common slightly.
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#     t u
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complex_shortcut2 = {'a':[NULL_REVISION], 'b':['a'], 'c':['b'], 'd':['c'],
3377.3.43 by John Arbash Meinel
Ian's review feedback
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                    'e':['d'], 'f':['e'], 'g':['f'], 'h':['d'], 'i':['g'],
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                    'j':['h'], 'k':['h', 'i'], 'l':['k'], 'm':['l'], 'n':['m'],
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                    'o':['n'], 'p':['o'], 'q':['p'], 'r':['q'], 's':['r'],
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                    't':['i', 's'], 'u':['s', 'j'], 
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
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                    }
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3377.3.36 by John Arbash Meinel
Small updates, try to write a test for the race condition.
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# Graph where different walkers will race to find the common and uncommon
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# nodes.
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#
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# NULL_REVISION
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#     |
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#     a
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#     |
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#     b
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#     |
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#     c
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#     |
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#     d
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#     |\
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#     e k
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#     | |
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#     f-+-p
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#     | | |
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#     | l |
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#     | | |
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#     | m |
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#     | |\|
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#     g n q
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#     |\| |
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#     h o |
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#     |/| |
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#     i r |
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#     | | |
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#     | s |
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#     | | |
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#     | t |
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#     | | |
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#     | u |
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#     | | |
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#     | v |
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#     | | |
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#     | w |
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#     | | |
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#     | x |
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#     | |\|
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#     | y z
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#     |/
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#     j
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#
3377.4.2 by John Arbash Meinel
Merge in the bzr.dev changes
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# x is found to be common right away, but is the start of a long series of
3377.3.36 by John Arbash Meinel
Small updates, try to write a test for the race condition.
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# common commits.
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# o is actually common, but the i-j shortcut makes it look like it is actually
3377.4.2 by John Arbash Meinel
Merge in the bzr.dev changes
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# unique to j at first, you have to traverse all of x->o to find it.
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# q,m gives the walker from j a common point to stop searching, as does p,f.
3377.3.36 by John Arbash Meinel
Small updates, try to write a test for the race condition.
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# k-n exists so that the second pass still has nodes that are worth searching,
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# rather than instantly cancelling the extra walker.
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racing_shortcuts = {'a':[NULL_REVISION], 'b':['a'], 'c':['b'], 'd':['c'],
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    'e':['d'], 'f':['e'], 'g':['f'], 'h':['g'], 'i':['h', 'o'], 'j':['i', 'y'],
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    'k':['d'], 'l':['k'], 'm':['l'], 'n':['m'], 'o':['n', 'g'], 'p':['f'],
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    'q':['p', 'm'], 'r':['o'], 's':['r'], 't':['s'], 'u':['t'], 'v':['u'],
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    'w':['v'], 'x':['w'], 'y':['x'], 'z':['x', 'q']}
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3377.3.35 by John Arbash Meinel
Add a test that exercises the multiple interesting unique code
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# A graph with multiple nodes unique to one side.
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#
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# NULL_REVISION
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#     |
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#     a
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#     |
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#     b
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#     |
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#     c
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#     |
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#     d
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#     |\
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#     e f
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#     |\ \
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#     g h i
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#     |\ \ \
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#     j k l m
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#     | |/ x|
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#     | n o p
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#     | |/  |
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#     | q   |
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#     | |   |
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#     | r   |
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#     | |   |
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#     | s   |
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#     | |   |
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#     | t   |
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#     | |   |
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#     | u   |
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#     | |   |
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#     | v   |
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#     | |   |
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#     | w   |
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#     | |   |
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#     | x   |
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#     |/ \ /
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#     y   z
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#
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multiple_interesting_unique = {'a':[NULL_REVISION], 'b':['a'], 'c':['b'],
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    'd':['c'], 'e':['d'], 'f':['d'], 'g':['e'], 'h':['e'], 'i':['f'],
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    'j':['g'], 'k':['g'], 'l':['h'], 'm':['i'], 'n':['k', 'l'],
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    'o':['m'], 'p':['m', 'l'], 'q':['n', 'o'], 'r':['q'], 's':['r'],
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    't':['s'], 'u':['t'], 'v':['u'], 'w':['v'], 'x':['w'],
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    'y':['j', 'x'], 'z':['x', 'p']}
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3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
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# Shortcut with extra root
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# We have a long history shortcut, and an extra root, which is why we can't
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# stop searchers based on seeing NULL_REVISION
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#  NULL_REVISION
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#       |   |
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#       a   |
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#       |\  |
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#       b | |
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#       | | |
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#       c | |
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#       | | |
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#       d | g
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#       |\|/
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#       e f
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shortcut_extra_root = {'a': [NULL_REVISION],
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                       'b': ['a'],
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                       'c': ['b'],
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                       'd': ['c'],
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                       'e': ['d'],
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                       'f': ['a', 'd', 'g'],
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                       'g': [NULL_REVISION],
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                      }
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2653.2.1 by Aaron Bentley
Implement Graph.is_ancestor
371
#  NULL_REVISION
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#       |
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#       f
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#       |
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#       e
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#      / \
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#     b   d
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#     | \ |
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#     a   c
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boundary = {'a': ['b'], 'c': ['b', 'd'], 'b':['e'], 'd':['e'], 'e': ['f'],
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            'f':[NULL_REVISION]}
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3228.4.2 by John Arbash Meinel
Add a Graph.iter_ancestry()
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# A graph that contains a ghost
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#  NULL_REVISION
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#       |
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#       f
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#       |
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#       e   g
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#      / \ /
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#     b   d
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#     | \ |
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#     a   c
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with_ghost = {'a': ['b'], 'c': ['b', 'd'], 'b':['e'], 'd':['e', 'g'],
3228.4.10 by John Arbash Meinel
Respond to abentley's review comments.
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              'e': ['f'], 'f':[NULL_REVISION], NULL_REVISION:()}
3228.4.2 by John Arbash Meinel
Add a Graph.iter_ancestry()
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3445.1.3 by John Arbash Meinel
Search from all of the known revisions.
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# A graph that shows we can shortcut finding revnos when reaching them from the
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# side.
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#  NULL_REVISION
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#       |
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#       a
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#       |
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#       b
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#       |
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#       c
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#       |
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#       d
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#       |
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#       e
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#      / \
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#     f   g
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#     |
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#     h
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#     |
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#     i
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with_tail = {'a':[NULL_REVISION], 'b':['a'], 'c':['b'], 'd':['c'], 'e':['d'],
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             'f':['e'], 'g':['e'], 'h':['f'], 'i':['h']}
3228.4.2 by John Arbash Meinel
Add a Graph.iter_ancestry()
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2653.2.1 by Aaron Bentley
Implement Graph.is_ancestor
423
class InstrumentedParentsProvider(object):
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    def __init__(self, parents_provider):
426
        self.calls = []
427
        self._real_parents_provider = parents_provider
428
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
429
    def get_parent_map(self, nodes):
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        self.calls.extend(nodes)
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        return self._real_parents_provider.get_parent_map(nodes)
432
2490.2.25 by Aaron Bentley
Update from review
433
3445.1.2 by John Arbash Meinel
Handle when a known revision is an ancestor.
434
class TestGraphBase(tests.TestCase):
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    def make_graph(self, ancestors):
437
        return _mod_graph.Graph(_mod_graph.DictParentsProvider(ancestors))
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    def make_breaking_graph(self, ancestors, break_on):
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        """Make a Graph that raises an exception if we hit a node."""
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        g = self.make_graph(ancestors)
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        orig_parent_map = g.get_parent_map
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        def get_parent_map(keys):
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            bad_keys = set(keys).intersection(break_on)
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            if bad_keys:
446
                self.fail('key(s) %s was accessed' % (sorted(bad_keys),))
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            return orig_parent_map(keys)
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        g.get_parent_map = get_parent_map
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        return g
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2490.2.31 by Aaron Bentley
Fix iter_topo_order to permit un-included parents
452
class TestGraph(TestCaseWithMemoryTransport):
2490.2.1 by Aaron Bentley
Start work on GraphWalker
453
2490.2.21 by Aaron Bentley
Rename graph to deprecated_graph
454
    def make_graph(self, ancestors):
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
455
        return _mod_graph.Graph(_mod_graph.DictParentsProvider(ancestors))
2490.2.3 by Aaron Bentley
Implement new merge base picker
456
2490.2.6 by Aaron Bentley
Use new common-ancestor code everywhere
457
    def prepare_memory_tree(self, location):
458
        tree = self.make_branch_and_memory_tree(location)
2490.2.1 by Aaron Bentley
Start work on GraphWalker
459
        tree.lock_write()
460
        tree.add('.')
2490.2.6 by Aaron Bentley
Use new common-ancestor code everywhere
461
        return tree
462
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    def build_ancestry(self, tree, ancestors):
2490.2.25 by Aaron Bentley
Update from review
464
        """Create an ancestry as specified by a graph dict
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        :param tree: A tree to use
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        :param ancestors: a dict of {node: [node_parent, ...]}
468
        """
2490.2.1 by Aaron Bentley
Start work on GraphWalker
469
        pending = [NULL_REVISION]
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        descendants = {}
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        for descendant, parents in ancestors.iteritems():
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            for parent in parents:
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                descendants.setdefault(parent, []).append(descendant)
474
        while len(pending) > 0:
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            cur_node = pending.pop()
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            for descendant in descendants.get(cur_node, []):
2490.2.3 by Aaron Bentley
Implement new merge base picker
477
                if tree.branch.repository.has_revision(descendant):
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                    continue
2490.2.1 by Aaron Bentley
Start work on GraphWalker
479
                parents = [p for p in ancestors[descendant] if p is not
480
                           NULL_REVISION]
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                if len([p for p in parents if not
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                    tree.branch.repository.has_revision(p)]) > 0:
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                    continue
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                tree.set_parent_ids(parents)
2490.2.3 by Aaron Bentley
Implement new merge base picker
485
                if len(parents) > 0:
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                    left_parent = parents[0]
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                else:
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                    left_parent = NULL_REVISION
2490.2.1 by Aaron Bentley
Start work on GraphWalker
489
                tree.branch.set_last_revision_info(
2490.2.3 by Aaron Bentley
Implement new merge base picker
490
                    len(tree.branch._lefthand_history(left_parent)),
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                    left_parent)
2490.2.1 by Aaron Bentley
Start work on GraphWalker
492
                tree.commit(descendant, rev_id=descendant)
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                pending.append(descendant)
2490.2.2 by Aaron Bentley
add minimal-common-ancestor calculation
494
2490.2.13 by Aaron Bentley
Update distinct -> lowest, refactor, add ParentsProvider concept
495
    def test_lca(self):
2490.2.25 by Aaron Bentley
Update from review
496
        """Test finding least common ancestor.
2490.2.3 by Aaron Bentley
Implement new merge base picker
497
498
        ancestry_1 should always have a single common ancestor
499
        """
2490.2.21 by Aaron Bentley
Rename graph to deprecated_graph
500
        graph = self.make_graph(ancestry_1)
2490.2.28 by Aaron Bentley
Fix handling of null revision
501
        self.assertRaises(errors.InvalidRevisionId, graph.find_lca, None)
2490.2.21 by Aaron Bentley
Rename graph to deprecated_graph
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'))
2490.2.3 by Aaron Bentley
Implement new merge base picker
508
2520.4.104 by Aaron Bentley
Avoid infinite loop when there is no unique lca
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
2490.2.13 by Aaron Bentley
Update distinct -> lowest, refactor, add ParentsProvider concept
515
    def test_lca_criss_cross(self):
2490.2.25 by Aaron Bentley
Update from review
516
        """Test least-common-ancestor after a criss-cross merge."""
2490.2.21 by Aaron Bentley
Rename graph to deprecated_graph
517
        graph = self.make_graph(criss_cross)
2490.2.3 by Aaron Bentley
Implement new merge base picker
518
        self.assertEqual(set(['rev2a', 'rev2b']),
2490.2.21 by Aaron Bentley
Rename graph to deprecated_graph
519
                         graph.find_lca('rev3a', 'rev3b'))
2490.2.3 by Aaron Bentley
Implement new merge base picker
520
        self.assertEqual(set(['rev2b']),
2490.2.25 by Aaron Bentley
Update from review
521
                         graph.find_lca('rev3a', 'rev3b', 'rev2b'))
2490.2.3 by Aaron Bentley
Implement new merge base picker
522
2490.2.13 by Aaron Bentley
Update distinct -> lowest, refactor, add ParentsProvider concept
523
    def test_lca_shortcut(self):
2490.2.25 by Aaron Bentley
Update from review
524
        """Test least-common ancestor on this history shortcut"""
2490.2.21 by Aaron Bentley
Rename graph to deprecated_graph
525
        graph = self.make_graph(history_shortcut)
526
        self.assertEqual(set(['rev2b']), graph.find_lca('rev3a', 'rev3b'))
2490.2.9 by Aaron Bentley
Fix minimal common ancestor algorithm for non-minimal perhipheral ancestors
527
2490.2.13 by Aaron Bentley
Update distinct -> lowest, refactor, add ParentsProvider concept
528
    def test_recursive_unique_lca(self):
2490.2.25 by Aaron Bentley
Update from review
529
        """Test finding a unique least common ancestor.
2490.2.3 by Aaron Bentley
Implement new merge base picker
530
531
        ancestry_1 should always have a single common ancestor
532
        """
2490.2.21 by Aaron Bentley
Rename graph to deprecated_graph
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'))
1551.19.10 by Aaron Bentley
Merge now warns when it encounters a criss-cross
540
        self.assertEqual(('rev1', 1,),
541
                         graph.find_unique_lca('rev2a', 'rev2b',
542
                         count_steps=True))
2490.2.3 by Aaron Bentley
Implement new merge base picker
543
3377.3.1 by John Arbash Meinel
Bring in some of the changes from graph_update and graph_optimization
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
2490.2.13 by Aaron Bentley
Update distinct -> lowest, refactor, add ParentsProvider concept
569
    def test_unique_lca_criss_cross(self):
570
        """Ensure we don't pick non-unique lcas in a criss-cross"""
2490.2.21 by Aaron Bentley
Rename graph to deprecated_graph
571
        graph = self.make_graph(criss_cross)
572
        self.assertEqual('rev1', graph.find_unique_lca('rev3a', 'rev3b'))
1551.19.10 by Aaron Bentley
Merge now warns when it encounters a criss-cross
573
        lca, steps = graph.find_unique_lca('rev3a', 'rev3b', count_steps=True)
574
        self.assertEqual('rev1', lca)
575
        self.assertEqual(2, steps)
2490.2.4 by Aaron Bentley
More tests for unique common ancestor
576
2490.2.13 by Aaron Bentley
Update distinct -> lowest, refactor, add ParentsProvider concept
577
    def test_unique_lca_null_revision(self):
2490.2.4 by Aaron Bentley
More tests for unique common ancestor
578
        """Ensure we pick NULL_REVISION when necessary"""
2490.2.21 by Aaron Bentley
Rename graph to deprecated_graph
579
        graph = self.make_graph(criss_cross2)
580
        self.assertEqual('rev1b', graph.find_unique_lca('rev2a', 'rev1b'))
2490.2.4 by Aaron Bentley
More tests for unique common ancestor
581
        self.assertEqual(NULL_REVISION,
2490.2.21 by Aaron Bentley
Rename graph to deprecated_graph
582
                         graph.find_unique_lca('rev2a', 'rev2b'))
2490.2.4 by Aaron Bentley
More tests for unique common ancestor
583
2490.2.13 by Aaron Bentley
Update distinct -> lowest, refactor, add ParentsProvider concept
584
    def test_unique_lca_null_revision2(self):
2490.2.4 by Aaron Bentley
More tests for unique common ancestor
585
        """Ensure we pick NULL_REVISION when necessary"""
2490.2.21 by Aaron Bentley
Rename graph to deprecated_graph
586
        graph = self.make_graph(ancestry_2)
2490.2.4 by Aaron Bentley
More tests for unique common ancestor
587
        self.assertEqual(NULL_REVISION,
2490.2.21 by Aaron Bentley
Rename graph to deprecated_graph
588
                         graph.find_unique_lca('rev4a', 'rev1b'))
2490.2.6 by Aaron Bentley
Use new common-ancestor code everywhere
589
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
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
2490.2.6 by Aaron Bentley
Use new common-ancestor code everywhere
594
    def test_common_ancestor_two_repos(self):
2490.2.13 by Aaron Bentley
Update distinct -> lowest, refactor, add ParentsProvider concept
595
        """Ensure we do unique_lca using data from two repos"""
2490.2.6 by Aaron Bentley
Use new common-ancestor code everywhere
596
        mainline_tree = self.prepare_memory_tree('mainline')
597
        self.build_ancestry(mainline_tree, mainline)
3010.1.6 by Robert Collins
Locking in test_graph.
598
        self.addCleanup(mainline_tree.unlock)
2490.2.6 by Aaron Bentley
Use new common-ancestor code everywhere
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)
3010.1.6 by Robert Collins
Locking in test_graph.
604
        self.addCleanup(feature_tree.unlock)
605
2490.2.21 by Aaron Bentley
Rename graph to deprecated_graph
606
        graph = mainline_tree.branch.repository.get_graph(
2490.2.6 by Aaron Bentley
Use new common-ancestor code everywhere
607
            feature_tree.branch.repository)
2490.2.21 by Aaron Bentley
Rename graph to deprecated_graph
608
        self.assertEqual('rev2b', graph.find_unique_lca('rev2a', 'rev3b'))
2490.2.23 by Aaron Bentley
Adapt find_borders to produce a graph difference
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
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
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
2490.2.23 by Aaron Bentley
Adapt find_borders to produce a graph difference
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'))
2490.2.25 by Aaron Bentley
Update from review
636
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
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)
3377.3.1 by John Arbash Meinel
Bring in some of the changes from graph_update and graph_optimization
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)
3377.3.13 by John Arbash Meinel
Change _search_for_extra_common slightly.
656
        self.assertEqual((set(['t']), set(['j', 'u'])),
657
                         graph.find_difference('t', 'u'))
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
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
3099.3.3 by John Arbash Meinel
Deprecate get_parents() in favor of get_parent_map()
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']))
2490.2.30 by Aaron Bentley
Add functionality for tsorting graphs
676
2490.2.31 by Aaron Bentley
Fix iter_topo_order to permit un-included parents
677
    def test_iter_topo_order(self):
2490.2.30 by Aaron Bentley
Add functionality for tsorting graphs
678
        graph = self.make_graph(ancestry_1)
679
        args = ['rev2a', 'rev3', 'rev1']
2490.2.31 by Aaron Bentley
Fix iter_topo_order to permit un-included parents
680
        topo_args = list(graph.iter_topo_order(args))
2490.2.30 by Aaron Bentley
Add functionality for tsorting graphs
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'))
2653.2.1 by Aaron Bentley
Implement Graph.is_ancestor
684
685
    def test_is_ancestor(self):
686
        graph = self.make_graph(ancestry_1)
2653.2.3 by Aaron Bentley
correctly handle Graph.is_ancestor(x, x)
687
        self.assertEqual(True, graph.is_ancestor('null:', 'null:'))
2653.2.1 by Aaron Bentley
Implement Graph.is_ancestor
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)
1551.15.78 by Aaron Bentley
Fix KeyError in filter_candidate_lca
712
3228.4.2 by John Arbash Meinel
Add a Graph.iter_ancestry()
713
    def test_iter_ancestry(self):
3228.4.10 by John Arbash Meinel
Respond to abentley's review comments.
714
        nodes = boundary.copy()
715
        nodes[NULL_REVISION] = ()
716
        graph = self.make_graph(nodes)
717
        expected = nodes.copy()
3228.4.2 by John Arbash Meinel
Add a Graph.iter_ancestry()
718
        expected.pop('a') # 'a' is not in the ancestry of 'c', all the
719
                          # other nodes are
3228.4.4 by John Arbash Meinel
Change iter_ancestry to take a group instead of a single node,
720
        self.assertEqual(expected, dict(graph.iter_ancestry(['c'])))
3228.4.10 by John Arbash Meinel
Respond to abentley's review comments.
721
        self.assertEqual(nodes, dict(graph.iter_ancestry(['a', 'c'])))
3228.4.2 by John Arbash Meinel
Add a Graph.iter_ancestry()
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
3228.4.10 by John Arbash Meinel
Respond to abentley's review comments.
727
        expected['g'] = None
3228.4.4 by John Arbash Meinel
Change iter_ancestry to take a group instead of a single node,
728
        self.assertEqual(expected, dict(graph.iter_ancestry(['a', 'c'])))
3228.4.2 by John Arbash Meinel
Add a Graph.iter_ancestry()
729
        expected.pop('a') 
3228.4.4 by John Arbash Meinel
Change iter_ancestry to take a group instead of a single node,
730
        self.assertEqual(expected, dict(graph.iter_ancestry(['c'])))
3228.4.2 by John Arbash Meinel
Add a Graph.iter_ancestry()
731
1551.15.78 by Aaron Bentley
Fix KeyError in filter_candidate_lca
732
    def test_filter_candidate_lca(self):
733
        """Test filter_candidate_lca for a corner case
734
1551.15.83 by Aaron Bentley
Update test documentation
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'.
1551.15.78 by Aaron Bentley
Fix KeyError in filter_candidate_lca
741
        """
742
        # This test is sensitive to the iteration order of dicts.  It will
1551.15.82 by Aaron Bentley
Add symmetrical alternative to test case
743
        # pass incorrectly if 'e' and 'a' sort before 'c'
1551.15.84 by Aaron Bentley
Add ancestry graph for test case
744
        #
745
        # NULL_REVISION
746
        #     / \
747
        #    a   e
748
        #    |   |
749
        #    b   d
750
        #     \ /
751
        #      c
1551.15.82 by Aaron Bentley
Add symmetrical alternative to test case
752
        graph = self.make_graph({'c': ['b', 'd'], 'd': ['e'], 'b': ['a'],
753
                                 'a': [NULL_REVISION], 'e': [NULL_REVISION]})
2776.1.4 by Robert Collins
Trivial review feedback changes.
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):
3052.5.5 by John Arbash Meinel
Special case Graph.heads() for NULL_REVISION rather than is_ancestor.
765
        # A single node will always be a head
2776.1.4 by Robert Collins
Trivial review feedback changes.
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']))
2921.3.1 by Robert Collins
* Graph ``heads()`` queries have been bugfixed to no longer access all
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
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
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
2921.3.1 by Robert Collins
* Graph ``heads()`` queries have been bugfixed to no longer access all
849
        an_obj = stub()
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
850
        an_obj.get_parent_map = get_parent_map
2921.3.1 by Robert Collins
* Graph ``heads()`` queries have been bugfixed to no longer access all
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']))
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
888
3177.3.1 by Robert Collins
* New method ``next_with_ghosts`` on the Graph breadth-first-search objects
889
    def test_breadth_first_search_start_ghosts(self):
3184.1.1 by Robert Collins
Add basic get_recipe to the graph breadth first searcher.
890
        graph = self.make_graph({})
3177.3.1 by Robert Collins
* New method ``next_with_ghosts`` on the Graph breadth-first-search objects
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):
3184.1.1 by Robert Collins
Add basic get_recipe to the graph breadth first searcher.
901
        graph = self.make_graph({
3177.3.1 by Robert Collins
* New method ``next_with_ghosts`` on the Graph breadth-first-search objects
902
            'head':['present'],
903
            'present':['child', 'ghost'],
904
            'child':[],
3184.1.1 by Robert Collins
Add basic get_recipe to the graph breadth first searcher.
905
            })
3177.3.1 by Robert Collins
* New method ``next_with_ghosts`` on the Graph breadth-first-search objects
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):
3177.3.3 by Robert Collins
Review feedback.
922
        # To make the API robust, we allow calling both next() and
923
        # next_with_ghosts() on the same searcher.
3184.1.1 by Robert Collins
Add basic get_recipe to the graph breadth first searcher.
924
        graph = self.make_graph({
3177.3.1 by Robert Collins
* New method ``next_with_ghosts`` on the Graph breadth-first-search objects
925
            'head':['present'],
926
            'present':['child', 'ghost'],
927
            'child':[],
3184.1.1 by Robert Collins
Add basic get_recipe to the graph breadth first searcher.
928
            })
3177.3.3 by Robert Collins
Review feedback.
929
        # start with next_with_ghosts
3177.3.1 by Robert Collins
* New method ``next_with_ghosts`` on the Graph breadth-first-search objects
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)
3177.3.3 by Robert Collins
Review feedback.
936
        # start with next
3177.3.1 by Robert Collins
* New method ``next_with_ghosts`` on the Graph breadth-first-search objects
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
3177.3.2 by Robert Collins
Update graph searchers stop_searching_any and start_searching for next_with_ghosts.
944
    def test_breadth_first_change_search(self):
3177.3.3 by Robert Collins
Review feedback.
945
        # Changing the search should work with both next and next_with_ghosts.
3184.1.1 by Robert Collins
Add basic get_recipe to the graph breadth first searcher.
946
        graph = self.make_graph({
3177.3.2 by Robert Collins
Update graph searchers stop_searching_any and start_searching for next_with_ghosts.
947
            'head':['present'],
948
            'present':['stopped'],
949
            'other':['other_2'],
950
            'other_2':[],
3184.1.1 by Robert Collins
Add basic get_recipe to the graph breadth first searcher.
951
            })
3177.3.2 by Robert Collins
Update graph searchers stop_searching_any and start_searching for next_with_ghosts.
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
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
971
    def assertSeenAndResult(self, instructions, search, next):
972
        """Check the results of .seen and get_result() for a seach.
3184.1.1 by Robert Collins
Add basic get_recipe to the graph breadth first searcher.
973
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
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.
3184.1.1 by Robert Collins
Add basic get_recipe to the graph breadth first searcher.
980
        :param search: The search to use.
981
        :param next: A callable to advance the search.
982
        """
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
983
        for seen, recipe, included_keys, starts, stops in instructions:
3184.1.1 by Robert Collins
Add basic get_recipe to the graph breadth first searcher.
984
            next()
3184.1.2 by Robert Collins
Add tests for starting and stopping searches in combination with get_recipe.
985
            if starts is not None:
986
                search.start_searching(starts)
987
            if stops is not None:
988
                search.stop_searching_any(stops)
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
989
            result = search.get_result()
990
            self.assertEqual(recipe, result.get_recipe())
991
            self.assertEqual(set(included_keys), result.get_keys())
3184.1.1 by Robert Collins
Add basic get_recipe to the graph breadth first searcher.
992
            self.assertEqual(seen, search.seen)
993
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
994
    def test_breadth_first_get_result_excludes_current_pending(self):
3184.1.1 by Robert Collins
Add basic get_recipe to the graph breadth first searcher.
995
        graph = self.make_graph({
996
            'head':['child'],
997
            'child':[NULL_REVISION],
3184.1.3 by Robert Collins
Automatically exclude ghosts.
998
            NULL_REVISION:[],
3184.1.1 by Robert Collins
Add basic get_recipe to the graph breadth first searcher.
999
            })
1000
        search = graph._make_breadth_first_searcher(['head'])
1001
        # At the start, nothing has been seen, to its all excluded:
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1002
        result = search.get_result()
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1003
        self.assertEqual((set(['head']), set(['head']), 0),
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1004
            result.get_recipe())
1005
        self.assertEqual(set(), result.get_keys())
3184.1.1 by Robert Collins
Add basic get_recipe to the graph breadth first searcher.
1006
        self.assertEqual(set(), search.seen)
1007
        # using next:
1008
        expected = [
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1009
            (set(['head']), (set(['head']), set(['child']), 1),
1010
             ['head'], None, None),
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1011
            (set(['head', 'child']), (set(['head']), set([NULL_REVISION]), 2),
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1012
             ['head', 'child'], None, None),
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1013
            (set(['head', 'child', NULL_REVISION]), (set(['head']), set(), 3),
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1014
             ['head', 'child', NULL_REVISION], None, None),
3184.1.1 by Robert Collins
Add basic get_recipe to the graph breadth first searcher.
1015
            ]
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1016
        self.assertSeenAndResult(expected, search, search.next)
3184.1.1 by Robert Collins
Add basic get_recipe to the graph breadth first searcher.
1017
        # using next_with_ghosts:
1018
        search = graph._make_breadth_first_searcher(['head'])
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1019
        self.assertSeenAndResult(expected, search, search.next_with_ghosts)
3184.1.1 by Robert Collins
Add basic get_recipe to the graph breadth first searcher.
1020
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1021
    def test_breadth_first_get_result_starts_stops(self):
3184.1.2 by Robert Collins
Add tests for starting and stopping searches in combination with get_recipe.
1022
        graph = self.make_graph({
1023
            'head':['child'],
1024
            'child':[NULL_REVISION],
1025
            'otherhead':['otherchild'],
1026
            'otherchild':['excluded'],
1027
            'excluded':[NULL_REVISION],
3184.1.3 by Robert Collins
Automatically exclude ghosts.
1028
            NULL_REVISION:[]
3184.1.2 by Robert Collins
Add tests for starting and stopping searches in combination with get_recipe.
1029
            })
1030
        search = graph._make_breadth_first_searcher([])
1031
        # Starting with nothing and adding a search works:
1032
        search.start_searching(['head'])
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1033
        # head has been seen:
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1034
        result = search.get_result()
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1035
        self.assertEqual((set(['head']), set(['child']), 1),
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1036
            result.get_recipe())
1037
        self.assertEqual(set(['head']), result.get_keys())
3184.1.2 by Robert Collins
Add tests for starting and stopping searches in combination with get_recipe.
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']),
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1045
             (set(['head', 'otherhead']), set(['child', 'otherchild']), 2),
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1046
             ['head', 'otherhead'], ['otherhead'], ['child']),
3184.1.2 by Robert Collins
Add tests for starting and stopping searches in combination with get_recipe.
1047
            (set(['head', 'child', 'otherhead', 'otherchild']),
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1048
             (set(['head', 'otherhead']), set(['child', 'excluded']), 3),
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1049
             ['head', 'otherhead', 'otherchild'], None, None),
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1050
            # stop searching excluded now
3184.1.2 by Robert Collins
Add tests for starting and stopping searches in combination with get_recipe.
1051
            (set(['head', 'child', 'otherhead', 'otherchild', 'excluded']),
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1052
             (set(['head', 'otherhead']), set(['child', 'excluded']), 3),
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1053
             ['head', 'otherhead', 'otherchild'], None, ['excluded']),
3184.1.2 by Robert Collins
Add tests for starting and stopping searches in combination with get_recipe.
1054
            ]
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1055
        self.assertSeenAndResult(expected, search, search.next)
3184.1.2 by Robert Collins
Add tests for starting and stopping searches in combination with get_recipe.
1056
        # using next_with_ghosts:
1057
        search = graph._make_breadth_first_searcher([])
1058
        search.start_searching(['head'])
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1059
        self.assertSeenAndResult(expected, search, search.next_with_ghosts)
3184.1.2 by Robert Collins
Add tests for starting and stopping searches in combination with get_recipe.
1060
3184.2.1 by Robert Collins
Handle stopping ghosts in searches properly.
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
3808.1.1 by Andrew Bennetts
Possible fix for bug in new _walk_to_common_revisions.
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']),
3808.1.4 by John Arbash Meinel
make _walk_to_common responsible for stopping ancestors
1104
             (set(['head']), set(['middle', 'child']), 1),
3808.1.3 by Andrew Bennetts
Add another test, this one currently failing. Perhaps the current behaviour should be considered ok, rather than a failure?
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
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1112
    def test_breadth_first_get_result_ghosts_are_excluded(self):
3184.1.3 by Robert Collins
Automatically exclude ghosts.
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']),
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1122
             (set(['head']), set(['ghost', 'child']), 1),
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1123
             ['head'], None, None),
3184.1.3 by Robert Collins
Automatically exclude ghosts.
1124
            (set(['head', 'child', 'ghost']),
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1125
             (set(['head']), set([NULL_REVISION, 'ghost']), 2),
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1126
             ['head', 'child'], None, None),
3184.1.3 by Robert Collins
Automatically exclude ghosts.
1127
            ]
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1128
        self.assertSeenAndResult(expected, search, search.next)
3184.1.3 by Robert Collins
Automatically exclude ghosts.
1129
        # using next_with_ghosts:
1130
        search = graph._make_breadth_first_searcher(['head'])
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1131
        self.assertSeenAndResult(expected, search, search.next_with_ghosts)
3184.1.3 by Robert Collins
Automatically exclude ghosts.
1132
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1133
    def test_breadth_first_get_result_starting_a_ghost_ghost_is_excluded(self):
3184.1.4 by Robert Collins
Correctly exclude ghosts when ghosts are started on an existing search.
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']),
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1143
             (set(['head', 'ghost']), set(['child', 'ghost']), 1),
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1144
             ['head'], ['ghost'], None),
3184.1.4 by Robert Collins
Correctly exclude ghosts when ghosts are started on an existing search.
1145
            (set(['head', 'child', 'ghost']),
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1146
             (set(['head', 'ghost']), set([NULL_REVISION, 'ghost']), 2),
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1147
             ['head', 'child'], None, None),
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1148
            ]
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1149
        self.assertSeenAndResult(expected, search, search.next)
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1150
        # using next_with_ghosts:
1151
        search = graph._make_breadth_first_searcher(['head'])
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1152
        self.assertSeenAndResult(expected, search, search.next_with_ghosts)
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
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),
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1164
             ['head'], None, None),
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1165
            (set(['head', NULL_REVISION]),
1166
             (set(['head']), set([]), 2),
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1167
             ['head', NULL_REVISION], None, None),
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1168
            ]
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1169
        self.assertSeenAndResult(expected, search, search.next)
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1170
        # using next_with_ghosts:
1171
        search = graph._make_breadth_first_searcher(['head'])
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1172
        self.assertSeenAndResult(expected, search, search.next_with_ghosts)
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1173
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1174
    def test_breadth_first_search_get_result_after_StopIteration(self):
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
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),
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1185
             ['head'], None, None),
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1186
            (set(['head', 'ghost', NULL_REVISION]),
1187
             (set(['head', 'ghost']), set(['ghost']), 2),
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1188
             ['head', NULL_REVISION], ['ghost'], None),
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1189
            ]
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1190
        self.assertSeenAndResult(expected, search, search.next)
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1191
        self.assertRaises(StopIteration, search.next)
1192
        self.assertEqual(set(['head', 'ghost', NULL_REVISION]), search.seen)
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1193
        result = search.get_result()
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1194
        self.assertEqual((set(['ghost', 'head']), set(['ghost']), 2),
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1195
            result.get_recipe())
1196
        self.assertEqual(set(['head', NULL_REVISION]), result.get_keys())
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1197
        # using next_with_ghosts:
1198
        search = graph._make_breadth_first_searcher(['head'])
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1199
        self.assertSeenAndResult(expected, search, search.next_with_ghosts)
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1200
        self.assertRaises(StopIteration, search.next)
1201
        self.assertEqual(set(['head', 'ghost', NULL_REVISION]), search.seen)
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1202
        result = search.get_result()
3184.1.5 by Robert Collins
Record the number of found revisions for cross checking.
1203
        self.assertEqual((set(['ghost', 'head']), set(['ghost']), 2),
3184.1.6 by Robert Collins
Create a SearchResult object which can be used as a replacement for sets.
1204
            result.get_recipe())
1205
        self.assertEqual(set(['head', NULL_REVISION]), result.get_keys())
3184.1.4 by Robert Collins
Correctly exclude ghosts when ghosts are started on an existing search.
1206
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
1207
3445.1.2 by John Arbash Meinel
Handle when a known revision is an ancestor.
1208
class TestFindUniqueAncestors(TestGraphBase):
3377.3.24 by John Arbash Meinel
For some reason find_unique_ancestors is much slower than it should be.
1209
3377.3.21 by John Arbash Meinel
Simple brute-force implementation of find_unique_ancestors
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
3377.3.24 by John Arbash Meinel
For some reason find_unique_ancestors is much slower than it should be.
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
3377.3.25 by John Arbash Meinel
A few more minimal ancestry checks
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,
3377.3.27 by John Arbash Meinel
some simple updates
1236
                                         ['a', 'b'])
3377.3.25 by John Arbash Meinel
A few more minimal ancestry checks
1237
        self.assertFindUniqueAncestors(graph, ['h'], 'h', ['i'])
1238
        self.assertFindUniqueAncestors(graph, ['e', 'g', 'i'], 'i', ['h'])
3377.3.27 by John Arbash Meinel
some simple updates
1239
        self.assertFindUniqueAncestors(graph, ['h'], 'h', ['g'])
3377.3.26 by John Arbash Meinel
Found a graph leak.
1240
        self.assertFindUniqueAncestors(graph, ['h'], 'h', ['j'])
1241
3377.3.21 by John Arbash Meinel
Simple brute-force implementation of find_unique_ancestors
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
3377.3.22 by John Arbash Meinel
include some tests using the complex graphs
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
3377.3.35 by John Arbash Meinel
Add a test that exercises the multiple interesting unique code
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
3377.3.36 by John Arbash Meinel
Small updates, try to write a test for the race condition.
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
3377.3.21 by John Arbash Meinel
Simple brute-force implementation of find_unique_ancestors
1282
3445.1.4 by John Arbash Meinel
Change the function to be called 'find_distance_to_null'
1283
class TestGraphFindDistanceToNull(TestGraphBase):
3445.1.1 by John Arbash Meinel
Start working on a new Graph api to make finding revision numbers faster.
1284
    """Test an api that should be able to compute a revno"""
1285
3445.1.4 by John Arbash Meinel
Change the function to be called 'find_distance_to_null'
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)
3445.1.1 by John Arbash Meinel
Start working on a new Graph api to make finding revision numbers faster.
1289
        self.assertEqual(revno, actual)
1290
1291
    def test_nothing_known(self):
1292
        graph = self.make_graph(ancestry_1)
3445.1.4 by John Arbash Meinel
Change the function to be called 'find_distance_to_null'
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', [])
3445.1.1 by John Arbash Meinel
Start working on a new Graph api to make finding revision numbers faster.
1299
1300
    def test_rev_is_ghost(self):
1301
        graph = self.make_graph(ancestry_1)
1302
        e = self.assertRaises(errors.GhostRevisionsHaveNoRevno,
3445.1.4 by John Arbash Meinel
Change the function to be called 'find_distance_to_null'
1303
                              graph.find_distance_to_null, 'rev_missing', [])
3445.1.1 by John Arbash Meinel
Start working on a new Graph api to make finding revision numbers faster.
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,
3445.1.4 by John Arbash Meinel
Change the function to be called 'find_distance_to_null'
1310
                              graph.find_distance_to_null, 'rev', [])
3445.1.1 by John Arbash Meinel
Start working on a new Graph api to make finding revision numbers faster.
1311
        self.assertEqual('rev', e.revision_id)
1312
        self.assertEqual('parent', e.ghost_revision_id)
1313
3445.1.2 by John Arbash Meinel
Handle when a known revision is an ancestor.
1314
    def test_known_in_ancestry(self):
1315
        graph = self.make_graph(ancestry_1)
3445.1.4 by John Arbash Meinel
Change the function to be called 'find_distance_to_null'
1316
        self.assertFindDistance(2, graph, 'rev2a', [('rev1', 1)])
1317
        self.assertFindDistance(3, graph, 'rev3', [('rev2a', 2)])
3445.1.2 by John Arbash Meinel
Handle when a known revision is an ancestor.
1318
1319
    def test_known_in_ancestry_limits(self):
3445.1.3 by John Arbash Meinel
Search from all of the known revisions.
1320
        graph = self.make_breaking_graph(ancestry_1, ['rev1'])
3445.1.4 by John Arbash Meinel
Change the function to be called 'find_distance_to_null'
1321
        self.assertFindDistance(4, graph, 'rev4', [('rev3', 3)])
3445.1.2 by John Arbash Meinel
Handle when a known revision is an ancestor.
1322
3445.1.3 by John Arbash Meinel
Search from all of the known revisions.
1323
    def test_target_is_ancestor(self):
1324
        graph = self.make_graph(ancestry_1)
3445.1.4 by John Arbash Meinel
Change the function to be called 'find_distance_to_null'
1325
        self.assertFindDistance(2, graph, 'rev2a', [('rev3', 3)])
3445.1.3 by John Arbash Meinel
Search from all of the known revisions.
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'])
3445.1.4 by John Arbash Meinel
Change the function to be called 'find_distance_to_null'
1330
        self.assertFindDistance(3, graph, 'rev3', [('rev4', 4)])
3445.1.3 by John Arbash Meinel
Search from all of the known revisions.
1331
1332
    def test_target_parallel_to_known_limits(self):
3445.1.8 by John Arbash Meinel
Clarity tweaks recommended by Ian
1333
        # Even though the known revision isn't part of the other ancestry, they
3445.1.3 by John Arbash Meinel
Search from all of the known revisions.
1334
        # eventually converge
1335
        graph = self.make_breaking_graph(with_tail, ['a'])
3445.1.4 by John Arbash Meinel
Change the function to be called 'find_distance_to_null'
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)])
3445.1.3 by John Arbash Meinel
Search from all of the known revisions.
1340
3445.1.1 by John Arbash Meinel
Start working on a new Graph api to make finding revision numbers faster.
1341
3514.2.8 by John Arbash Meinel
The insertion ordering into the weave has an impact on conflicts.
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
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
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
3099.3.3 by John Arbash Meinel
Deprecate get_parents() in favor of get_parent_map()
1380
    def test_get_parent_map(self):
1381
        """Requesting the same revision should be returned from cache"""
3835.1.16 by Aaron Bentley
Updates from review
1382
        self.assertEqual({}, self.caching_pp._cache)
3099.3.3 by John Arbash Meinel
Deprecate get_parents() in favor of get_parent_map()
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)
3835.1.16 by Aaron Bentley
Updates from review
1388
        self.assertEqual({'a':('b',)}, self.caching_pp._cache)
3099.3.3 by John Arbash Meinel
Deprecate get_parents() in favor of get_parent_map()
1389
1390
    def test_get_parent_map_not_present(self):
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
1391
        """The cache should also track when a revision doesn't exist"""
3099.3.3 by John Arbash Meinel
Deprecate get_parents() in favor of get_parent_map()
1392
        self.assertEqual({}, self.caching_pp.get_parent_map(['b']))
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
1393
        self.assertEqual(['b'], self.inst_pp.calls)
3099.3.3 by John Arbash Meinel
Deprecate get_parents() in favor of get_parent_map()
1394
        self.assertEqual({}, self.caching_pp.get_parent_map(['b']))
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
1395
        # No new calls
1396
        self.assertEqual(['b'], self.inst_pp.calls)
3835.1.16 by Aaron Bentley
Updates from review
1397
        self.assertEqual({'b':None}, self.caching_pp._cache)
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
1398
3099.3.3 by John Arbash Meinel
Deprecate get_parents() in favor of get_parent_map()
1399
    def test_get_parent_map_mixed(self):
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
1400
        """Anything that can be returned from cache, should be"""
3099.3.3 by John Arbash Meinel
Deprecate get_parents() in favor of get_parent_map()
1401
        self.assertEqual({}, self.caching_pp.get_parent_map(['b']))
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
1402
        self.assertEqual(['b'], self.inst_pp.calls)
3099.3.3 by John Arbash Meinel
Deprecate get_parents() in favor of get_parent_map()
1403
        self.assertEqual({'a':('b',)},
1404
                         self.caching_pp.get_parent_map(['a', 'b']))
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
1405
        self.assertEqual(['b', 'a'], self.inst_pp.calls)
1406
3099.3.3 by John Arbash Meinel
Deprecate get_parents() in favor of get_parent_map()
1407
    def test_get_parent_map_repeated(self):
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
1408
        """Asking for the same parent 2x will only forward 1 request."""
3099.3.3 by John Arbash Meinel
Deprecate get_parents() in favor of get_parent_map()
1409
        self.assertEqual({'a':('b',)},
1410
                         self.caching_pp.get_parent_map(['b', 'a', 'b']))
3099.3.1 by John Arbash Meinel
Implement get_parent_map for ParentProviders
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))
3514.2.14 by John Arbash Meinel
Bring in the code to collapse linear portions of the graph.
1414
1415
3835.1.12 by Aaron Bentley
Unify CachingExtraParentsProvider and CachingParentsProvider.
1416
class TestCachingParentsProviderExtras(tests.TestCaseWithTransport):
3835.1.16 by Aaron Bentley
Updates from review
1417
    """Test the behaviour when parents are provided that were not requested."""
3835.1.10 by Aaron Bentley
Move CachingExtraParentsProvider to Graph
1418
1419
    def setUp(self):
3835.1.12 by Aaron Bentley
Unify CachingExtraParentsProvider and CachingParentsProvider.
1420
        super(TestCachingParentsProviderExtras, self).setUp()
3835.1.11 by Aaron Bentley
Rename FakeParentsProvider to ExtraParentsProvider
1421
        class ExtraParentsProvider(object):
3835.1.10 by Aaron Bentley
Move CachingExtraParentsProvider to Graph
1422
1423
            def get_parent_map(self, keys):
1424
                return {'rev1': [], 'rev2': ['rev1',]}
1425
3835.1.11 by Aaron Bentley
Rename FakeParentsProvider to ExtraParentsProvider
1426
        self.inst_pp = InstrumentedParentsProvider(ExtraParentsProvider())
3835.1.12 by Aaron Bentley
Unify CachingExtraParentsProvider and CachingParentsProvider.
1427
        self.caching_pp = _mod_graph.CachingParentsProvider(
1428
            get_parent_map=self.inst_pp.get_parent_map)
3835.1.10 by Aaron Bentley
Move CachingExtraParentsProvider to Graph
1429
1430
    def test_uncached(self):
3835.1.12 by Aaron Bentley
Unify CachingExtraParentsProvider and CachingParentsProvider.
1431
        self.caching_pp.disable_cache()
3835.1.10 by Aaron Bentley
Move CachingExtraParentsProvider to Graph
1432
        self.assertEqual({'rev1': []},
1433
                         self.caching_pp.get_parent_map(['rev1']))
1434
        self.assertEqual(['rev1'], self.inst_pp.calls)
3835.1.16 by Aaron Bentley
Updates from review
1435
        self.assertIs(None, self.caching_pp._cache)
1436
1437
    def test_cache_initially_empty(self):
1438
        self.assertEqual({}, self.caching_pp._cache)
3835.1.10 by Aaron Bentley
Move CachingExtraParentsProvider to Graph
1439
1440
    def test_cached(self):
1441
        self.assertEqual({'rev1': []},
1442
                         self.caching_pp.get_parent_map(['rev1']))
1443
        self.assertEqual(['rev1'], self.inst_pp.calls)
1444
        self.assertEqual({'rev1': [], 'rev2': ['rev1']},
3835.1.16 by Aaron Bentley
Updates from review
1445
                         self.caching_pp._cache)
3835.1.10 by Aaron Bentley
Move CachingExtraParentsProvider to Graph
1446
        self.assertEqual({'rev1': []},
1447
                          self.caching_pp.get_parent_map(['rev1']))
1448
        self.assertEqual(['rev1'], self.inst_pp.calls)
3835.1.16 by Aaron Bentley
Updates from review
1449
1450
    def test_disable_cache_clears_cache(self):
1451
        # Put something in the cache
1452
        self.caching_pp.get_parent_map(['rev1'])
1453
        self.assertEqual(2, len(self.caching_pp._cache))
3835.1.10 by Aaron Bentley
Move CachingExtraParentsProvider to Graph
1454
        self.caching_pp.disable_cache()
3835.1.16 by Aaron Bentley
Updates from review
1455
        self.assertIs(None, self.caching_pp._cache)
3835.1.10 by Aaron Bentley
Move CachingExtraParentsProvider to Graph
1456
3835.1.19 by Aaron Bentley
Raise exception when caching is enabled twice.
1457
    def test_enable_cache_raises(self):
3835.1.20 by Aaron Bentley
Change custom error to an AssertionError.
1458
        e = self.assertRaises(AssertionError, self.caching_pp.enable_cache)
3835.1.19 by Aaron Bentley
Raise exception when caching is enabled twice.
1459
        self.assertEqual('Cache enabled when already enabled.', str(e))
1460
3835.1.15 by Aaron Bentley
Allow miss caching to be disabled.
1461
    def test_cache_misses(self):
1462
        self.caching_pp.get_parent_map(['rev3'])
1463
        self.caching_pp.get_parent_map(['rev3'])
1464
        self.assertEqual(['rev3'], self.inst_pp.calls)
1465
1466
    def test_no_cache_misses(self):
3835.1.19 by Aaron Bentley
Raise exception when caching is enabled twice.
1467
        self.caching_pp.disable_cache()
3835.1.15 by Aaron Bentley
Allow miss caching to be disabled.
1468
        self.caching_pp.enable_cache(cache_misses=False)
1469
        self.caching_pp.get_parent_map(['rev3'])
1470
        self.caching_pp.get_parent_map(['rev3'])
1471
        self.assertEqual(['rev3', 'rev3'], self.inst_pp.calls)
1472
3835.1.10 by Aaron Bentley
Move CachingExtraParentsProvider to Graph
1473
    def test_cache_extras(self):
1474
        self.assertEqual({}, self.caching_pp.get_parent_map(['rev3']))
1475
        self.assertEqual({'rev2': ['rev1']},
1476
                         self.caching_pp.get_parent_map(['rev2']))
1477
        self.assertEqual(['rev3'], self.inst_pp.calls)
1478
1479
3514.2.14 by John Arbash Meinel
Bring in the code to collapse linear portions of the graph.
1480
class TestCollapseLinearRegions(tests.TestCase):
1481
1482
    def assertCollapsed(self, collapsed, original):
1483
        self.assertEqual(collapsed,
1484
                         _mod_graph.collapse_linear_regions(original))
1485
1486
    def test_collapse_nothing(self):
1487
        d = {1:[2, 3], 2:[], 3:[]}
1488
        self.assertCollapsed(d, d)
1489
        d = {1:[2], 2:[3, 4], 3:[5], 4:[5], 5:[]}
1490
        self.assertCollapsed(d, d)
1491
1492
    def test_collapse_chain(self):
1493
        # Any time we have a linear chain, we should be able to collapse
1494
        d = {1:[2], 2:[3], 3:[4], 4:[5], 5:[]}
1495
        self.assertCollapsed({1:[5], 5:[]}, d)
1496
        d = {5:[4], 4:[3], 3:[2], 2:[1], 1:[]}
1497
        self.assertCollapsed({5:[1], 1:[]}, d)
1498
        d = {5:[3], 3:[4], 4:[1], 1:[2], 2:[]}
1499
        self.assertCollapsed({5:[2], 2:[]}, d)
1500
1501
    def test_collapse_with_multiple_children(self):
1502
        #    7
1503
        #    |
1504
        #    6
1505
        #   / \
1506
        #  4   5
1507
        #  |   |
3514.2.16 by John Arbash Meinel
Review feedback from Ian.
1508
        #  2   3
3514.2.14 by John Arbash Meinel
Bring in the code to collapse linear portions of the graph.
1509
        #   \ /
1510
        #    1
1511
        #
1512
        # 4 and 5 cannot be removed because 6 has 2 children
3514.2.16 by John Arbash Meinel
Review feedback from Ian.
1513
        # 2 and 3 cannot be removed because 1 has 2 parents
3514.2.14 by John Arbash Meinel
Bring in the code to collapse linear portions of the graph.
1514
        d = {1:[2, 3], 2:[4], 4:[6], 3:[5], 5:[6], 6:[7], 7:[]}
1515
        self.assertCollapsed(d, d)