1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
|
# Copyright (C) 2005 by Canonical Ltd
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
"""Tests for topological sort."""
from bzrlib.tests import TestCase
from bzrlib.tsort import topo_sort, TopoSorter
from bzrlib.errors import GraphCycleError
class TopoSortTests(TestCase):
def assertSortAndIterate(self, graph, result_list):
"""Check that sorting and iter_topo_order on graph works."""
self.assertEquals(result_list, topo_sort(graph))
self.assertEqual(result_list,
list(TopoSorter(graph).iter_topo_order()))
def assertSortAndIterateRaise(self, exception_type, graph):
"""Try both iterating and topo_sorting graph and expect an exception."""
self.assertRaises(exception_type, topo_sort, graph)
self.assertRaises(exception_type,
list,
TopoSorter(graph).iter_topo_order())
def test_tsort_empty(self):
"""TopoSort empty list"""
self.assertSortAndIterate([], [])
def test_tsort_easy(self):
"""TopoSort list with one node"""
self.assertSortAndIterate({0: []}.items(), [0])
def test_tsort_cycle(self):
"""TopoSort traps graph with cycles"""
self.assertSortAndIterateRaise(GraphCycleError,
{0: [1],
1: [0]}.items())
def test_tsort_cycle_2(self):
"""TopoSort traps graph with longer cycle"""
self.assertSortAndIterateRaise(GraphCycleError,
{0: [1],
1: [2],
2: [0]}.items())
def test_tsort_1(self):
"""TopoSort simple nontrivial graph"""
self.assertSortAndIterate({0: [3],
1: [4],
2: [1, 4],
3: [],
4: [0, 3]}.items(),
[3, 0, 4, 1, 2])
def test_tsort_partial(self):
"""Topological sort with partial ordering.
If the graph does not give an order between two nodes, they are
returned in lexicographical order.
"""
self.assertSortAndIterate(([(0, []),
(1, [0]),
(2, [0]),
(3, [0]),
(4, [1, 2, 3]),
(5, [1, 2]),
(6, [1, 2]),
(7, [2, 3]),
(8, [0, 1, 4, 5, 6])]),
[0, 1, 2, 3, 4, 5, 6, 7, 8])
|