1 //
2 // Copyright (C) 2010 The Android Open Source Project
3 //
4 // Licensed under the Apache License, Version 2.0 (the "License");
5 // you may not use this file except in compliance with the License.
6 // You may obtain a copy of the License at
7 //
8 //      http://www.apache.org/licenses/LICENSE-2.0
9 //
10 // Unless required by applicable law or agreed to in writing, software
11 // distributed under the License is distributed on an "AS IS" BASIS,
12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 // See the License for the specific language governing permissions and
14 // limitations under the License.
15 //
16 
17 #include "update_engine/payload_generator/tarjan.h"
18 
19 #include <string>
20 #include <utility>
21 
22 #include <base/logging.h>
23 #include <gtest/gtest.h>
24 
25 #include "update_engine/common/utils.h"
26 #include "update_engine/payload_generator/graph_types.h"
27 
28 using std::make_pair;
29 using std::string;
30 using std::vector;
31 
32 namespace chromeos_update_engine {
33 
34 class TarjanAlgorithmTest : public ::testing::Test {};
35 
36 TEST(TarjanAlgorithmTest, SimpleTest) {
37   const Vertex::Index n_a = 0;
38   const Vertex::Index n_b = 1;
39   const Vertex::Index n_c = 2;
40   const Vertex::Index n_d = 3;
41   const Vertex::Index n_e = 4;
42   const Vertex::Index n_f = 5;
43   const Vertex::Index n_g = 6;
44   const Vertex::Index n_h = 7;
45   const Graph::size_type kNodeCount = 8;
46 
47   Graph graph(kNodeCount);
48 
49   graph[n_a].out_edges.insert(make_pair(n_e, EdgeProperties()));
50   graph[n_a].out_edges.insert(make_pair(n_f, EdgeProperties()));
51   graph[n_b].out_edges.insert(make_pair(n_a, EdgeProperties()));
52   graph[n_c].out_edges.insert(make_pair(n_d, EdgeProperties()));
53   graph[n_d].out_edges.insert(make_pair(n_e, EdgeProperties()));
54   graph[n_d].out_edges.insert(make_pair(n_f, EdgeProperties()));
55   graph[n_e].out_edges.insert(make_pair(n_b, EdgeProperties()));
56   graph[n_e].out_edges.insert(make_pair(n_c, EdgeProperties()));
57   graph[n_e].out_edges.insert(make_pair(n_f, EdgeProperties()));
58   graph[n_f].out_edges.insert(make_pair(n_g, EdgeProperties()));
59   graph[n_g].out_edges.insert(make_pair(n_h, EdgeProperties()));
60   graph[n_h].out_edges.insert(make_pair(n_g, EdgeProperties()));
61 
62   TarjanAlgorithm tarjan;
63 
64   for (Vertex::Index i = n_a; i <= n_e; i++) {
65     vector<Vertex::Index> vertex_indexes;
66     tarjan.Execute(i, &graph, &vertex_indexes);
67 
68     EXPECT_EQ(5U, vertex_indexes.size());
69     EXPECT_TRUE(utils::VectorContainsValue(vertex_indexes, n_a));
70     EXPECT_TRUE(utils::VectorContainsValue(vertex_indexes, n_b));
71     EXPECT_TRUE(utils::VectorContainsValue(vertex_indexes, n_c));
72     EXPECT_TRUE(utils::VectorContainsValue(vertex_indexes, n_d));
73     EXPECT_TRUE(utils::VectorContainsValue(vertex_indexes, n_e));
74   }
75 
76   {
77     vector<Vertex::Index> vertex_indexes;
78     tarjan.Execute(n_f, &graph, &vertex_indexes);
79 
80     EXPECT_EQ(1U, vertex_indexes.size());
81     EXPECT_TRUE(utils::VectorContainsValue(vertex_indexes, n_f));
82   }
83 
84   for (Vertex::Index i = n_g; i <= n_h; i++) {
85     vector<Vertex::Index> vertex_indexes;
86     tarjan.Execute(i, &graph, &vertex_indexes);
87 
88     EXPECT_EQ(2U, vertex_indexes.size());
89     EXPECT_TRUE(utils::VectorContainsValue(vertex_indexes, n_g));
90     EXPECT_TRUE(utils::VectorContainsValue(vertex_indexes, n_h));
91   }
92 }
93 
94 }  // namespace chromeos_update_engine
95