Ticket #7597: transform_output_iterator_test.cpp

File transform_output_iterator_test.cpp, 4.8 KB (added by louis.dionne92@…, 10 years ago)

unit test

Line 
1// Copyright Louis Dionne 2012. Use, modification and distribution is subject
2// to the Boost Software License, Version 1.0. (See accompanying file
3// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
4
5#include <boost/iterator/transform_output_iterator.hpp>
6#include <boost/concept/assert.hpp>
7#include <boost/concept/usage.hpp>
8#include <boost/concept_archetype.hpp>
9#include <boost/concept_check.hpp>
10#include <boost/iterator/counting_iterator.hpp>
11#include <boost/iterator/iterator_concepts.hpp>
12#include <boost/iterator/iterator_traits.hpp>
13
14#include <algorithm>
15#include <cassert>
16#include <iterator>
17#include <string>
18#include <vector>
19
20
21namespace transform_output_iterator_test {
22
23template <typename Iterator, typename OutputType = typename
24 boost::iterator_value<Iterator>::type>
25struct test_concepts {
26 BOOST_CONCEPT_USAGE(test_concepts) {
27 BOOST_CONCEPT_ASSERT((boost::OutputIterator<
28 boost::transform_output_iterator<
29 OutputType (*)(OutputType),
30 Iterator
31 >,
32 OutputType
33 >));
34
35 BOOST_CONCEPT_ASSERT((boost_concepts::WritableIterator<
36 boost::transform_output_iterator<
37 OutputType (*)(OutputType),
38 Iterator
39 >,
40 OutputType
41 >));
42
43 BOOST_CONCEPT_ASSERT((boost_concepts::IncrementableIterator<
44 boost::transform_output_iterator<
45 OutputType (*)(OutputType),
46 Iterator
47 >
48 >));
49 }
50};
51
52struct dummy { };
53BOOST_CONCEPT_ASSERT((
54 test_concepts<boost::output_iterator_archetype<dummy>, dummy>
55));
56BOOST_CONCEPT_ASSERT((
57 test_concepts<boost::input_output_iterator_archetype<dummy>, dummy>
58));
59BOOST_CONCEPT_ASSERT((
60 test_concepts<boost::mutable_forward_iterator_archetype<dummy> >
61));
62BOOST_CONCEPT_ASSERT((
63 test_concepts<boost::mutable_bidirectional_iterator_archetype<dummy> >
64));
65BOOST_CONCEPT_ASSERT((
66 test_concepts<boost::mutable_random_access_iterator_archetype<dummy> >
67));
68
69template <typename T = int>
70struct Multiply {
71 T n_;
72 Multiply(T n) : n_(n) { }
73 T operator()(T val) const {
74 return val * n_;
75 }
76};
77
78template <typename T = int>
79struct Add {
80 T n_;
81 Add(T n) : n_(n) { }
82 T operator()(T val) const {
83 return val + n_;
84 }
85};
86
87void should_transform_output() {
88 std::vector<int> actual, expected;
89 std::copy(boost::counting_iterator<int>(0),
90 boost::counting_iterator<int>(10),
91 boost::make_transform_output_iterator(
92 Add<>(10), std::back_inserter(actual)));
93
94 std::copy(boost::counting_iterator<int>(10),
95 boost::counting_iterator<int>(20),
96 std::back_inserter(expected));
97
98 assert(actual == expected);
99}
100
101void should_allow_chaining() {
102 std::vector<int> actual, expected;
103
104 boost::transform_output_iterator<Multiply<>,
105 boost::transform_output_iterator<Add<>,
106 std::back_insert_iterator<std::vector<int> > > > output =
107 boost::make_transform_output_iterator(
108 Multiply<>(2),std::back_inserter(actual)).and_then(Add<>(10));
109
110 std::copy(boost::counting_iterator<int>(0),
111 boost::counting_iterator<int>(5),
112 output);
113
114 expected.push_back(0 * 2 + 10);
115 expected.push_back(1 * 2 + 10);
116 expected.push_back(2 * 2 + 10);
117 expected.push_back(3 * 2 + 10);
118 expected.push_back(4 * 2 + 10);
119
120 assert(actual == expected);
121}
122
123void should_work_for_const_iterator_if_wrapped_iter_has_const_deref() {
124 typedef boost::transform_output_iterator<Multiply<>,
125 std::vector<int>::iterator> OutputIter;
126 std::vector<int> actual(1), expected;
127 OutputIter const out(Multiply<>(2), actual.begin());
128 *out = 3;
129
130 expected.push_back(2 * 3);
131
132 assert(actual == expected);
133}
134
135void chain_performs_operation_in_right_order() {
136 std::string actual;
137 typedef Add<std::string> Append;
138 *boost::make_transform_output_iterator(Append("a"), &actual).
139 and_then(Append("b"))
140 .and_then(Append("c"))
141 .and_then(Append("d")) = "";
142
143 assert(actual == "abcd");
144}
145
146} // end transform_output_iterator_test namespace
147
148
149int main() {
150 using namespace transform_output_iterator_test;
151 should_transform_output();
152 should_allow_chaining();
153 should_work_for_const_iterator_if_wrapped_iter_has_const_deref();
154 chain_performs_operation_in_right_order();
155 return 0;
156}