1 | // (C) Copyright Herve Bronnimann 2004. |
2 | // Use, modification and distribution are subject to the |
3 | // Boost Software License, Version 1.0. (See accompanying file |
4 | // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
5 | |
6 | #include <utility> |
7 | #include <functional> |
8 | |
9 | #include <boost/config.hpp> |
10 | #include <boost/algorithm/minmax.hpp> |
11 | |
12 | #define BOOST_TEST_MAIN |
13 | #include <boost/test/unit_test.hpp> |
14 | |
15 | class custom { |
16 | int m_x; |
17 | friend std::ostream& operator<<(std::ostream& str, custom const& x); |
18 | public: |
19 | explicit custom(int x = 0) : m_x(x) {} |
20 | custom(custom const& y) : m_x(y.m_x) {} |
21 | bool operator==(custom const& y) const { return m_x == y.m_x; } |
22 | bool operator<(custom const& y) const { return m_x < y.m_x; } |
23 | custom operator+(custom const& y) const { return custom(m_x+y.m_x); } |
24 | custom& operator+=(custom const& y) { m_x += y.m_x; return *this; } |
25 | }; |
26 | |
27 | std::ostream& |
28 | operator<<(std::ostream& str, custom const& x) |
29 | { |
30 | return str << x.m_x; |
31 | } |
32 | |
33 | template <class Value> |
34 | struct less_count : std::less<Value> { |
35 | typedef std::less<Value> Base; |
36 | less_count(less_count<Value> const& lc) : m_counter(lc.m_counter) {} |
37 | less_count(int& counter) : m_counter(counter) {} |
38 | bool operator()(Value const& a, Value const& b) const { |
39 | ++m_counter; |
40 | return Base::operator()(a,b); |
41 | } |
42 | void reset() { |
43 | m_counter = 0; |
44 | } |
45 | private: |
46 | int& m_counter; |
47 | }; |
48 | |
49 | using namespace boost; |
50 | |
51 | template <class Value> |
52 | void test(BOOST_EXPLICIT_TEMPLATE_TYPE(Value)) |
53 | { |
54 | Value zero(0), one(1); |
55 | int counter = 0; |
56 | less_count<Value> lc(counter); |
57 | |
58 | // Test functionality |
59 | tuple<Value const&, Value const&> result1 = boost::minmax(zero, one); |
60 | BOOST_CHECK_EQUAL( get<0>(result1), zero ); |
61 | BOOST_CHECK_EQUAL( get<1>(result1), one ); |
62 | |
63 | tuple<Value const&, Value const&> result2 = boost::minmax(one, zero); |
64 | BOOST_CHECK_EQUAL( get<0>(result2), zero ); |
65 | BOOST_CHECK_EQUAL( get<1>(result2), one ); |
66 | |
67 | // Test functionality and number of comparisons |
68 | lc.reset(); |
69 | tuple<Value const&, Value const&> result3 = boost::minmax(zero, one, lc ); |
70 | BOOST_CHECK_EQUAL( get<0>(result3), zero ); |
71 | BOOST_CHECK_EQUAL( get<1>(result3), one ); |
72 | BOOST_CHECK_EQUAL( counter, 1 ); |
73 | |
74 | lc.reset(); |
75 | tuple<Value const&, Value const&> result4 = boost::minmax(one, zero, lc ); |
76 | BOOST_CHECK_EQUAL( get<0>(result4), zero ); |
77 | BOOST_CHECK_EQUAL( get<1>(result4), one ); |
78 | BOOST_CHECK_EQUAL( counter, 1); |
79 | } |
80 | |
81 | BOOST_AUTO_TEST_CASE( test_main ) |
82 | { |
83 | test<int>(); // ("builtin"); |
84 | test<custom>(); // ("custom "); |
85 | } |
86 | |