1 // Copyright 2003 David Abrahams and Jeremy Siek
2 // Copyright 2019 Hans Dembinski
3 //
4 // Distributed under the Boost Software License, Version 1.0.
5 // (See accompanying file LICENSE_1_0.txt
6 // or copy at http://www.boost.org/LICENSE_1_0.txt)
7
8 #ifndef BOOST_HISTOGRAM_TEST_ITERATOR_TESTS_HPP
9 #define BOOST_HISTOGRAM_TEST_ITERATOR_TESTS_HPP
10
11 // This file contains adapted code from
12 // - boost::core::iterator; boost/pending/iterator_tests.hpp
13 // - boost::core::conversion; boost/implicit_cast.hpp
14
15 #include <boost/core/ignore_unused.hpp>
16 #include <boost/core/lightweight_test.hpp>
17 #include <iterator>
18 #include <type_traits>
19
20 namespace boost {
21 namespace histogram {
22
23 namespace detail {
24 template <class T>
25 struct icast_identity {
26 typedef T type;
27 };
28 } // namespace detail
29
30 template <class T>
implicit_cast(typename detail::icast_identity<T>::type x)31 inline T implicit_cast(typename detail::icast_identity<T>::type x) {
32 return x;
33 }
34
35 // use this for the value type
36 struct dummyT {
dummyTboost::histogram::dummyT37 dummyT() {}
dummyTboost::histogram::dummyT38 dummyT(char) {}
dummyTboost::histogram::dummyT39 dummyT(int x) : m_x(x) {}
fooboost::histogram::dummyT40 int foo() const { return m_x; }
operator ==boost::histogram::dummyT41 bool operator==(const dummyT& d) const { return m_x == d.m_x; }
42 int m_x;
43 };
44
45 // Tests whether type Iterator satisfies the requirements for a
46 // TrivialIterator.
47 // Preconditions: i != j, *i == val
48 template <class Iterator, class T>
trivial_iterator_test(const Iterator i,const Iterator j,T val)49 void trivial_iterator_test(const Iterator i, const Iterator j, T val) {
50 Iterator k;
51 BOOST_TEST(i == i);
52 BOOST_TEST(j == j);
53 BOOST_TEST(i != j);
54 typename std::iterator_traits<Iterator>::value_type v = *i;
55 BOOST_TEST(v == val);
56 ignore_unused(v);
57 BOOST_TEST(v == i->foo());
58 k = i;
59 BOOST_TEST(k == k);
60 BOOST_TEST(k == i);
61 BOOST_TEST(k != j);
62 BOOST_TEST(*k == val);
63 ignore_unused(k);
64 }
65
66 // Preconditions: i != j
67 template <class Iterator, class T>
mutable_trivial_iterator_test(const Iterator i,const Iterator j,T val)68 void mutable_trivial_iterator_test(const Iterator i, const Iterator j, T val) {
69 *i = val;
70 trivial_iterator_test(i, j, val);
71 }
72
73 // Preconditions: *i == v1, *++i == v2
74 template <class Iterator, class T>
input_iterator_test(Iterator i,T v1,T v2)75 void input_iterator_test(Iterator i, T v1, T v2) {
76 Iterator i1(i);
77
78 BOOST_TEST(i == i1);
79 BOOST_TEST(!(i != i1));
80
81 // I can see no generic way to create an input iterator
82 // that is in the domain of== of i and != i.
83 // The following works for istream_iterator but is not
84 // guaranteed to work for arbitrary input iterators.
85 //
86 // Iterator i2;
87 //
88 // BOOST_TEST(i != i2);
89 // BOOST_TEST(!(i == i2));
90
91 BOOST_TEST(*i1 == v1);
92 BOOST_TEST(*i == v1);
93
94 // we cannot test for equivalence of (void)++i & (void)i++
95 // as i is only guaranteed to be single pass.
96 BOOST_TEST(*i++ == v1);
97 ignore_unused(i1);
98
99 i1 = i;
100
101 BOOST_TEST(i == i1);
102 BOOST_TEST(!(i != i1));
103
104 BOOST_TEST(*i1 == v2);
105 BOOST_TEST(*i == v2);
106 ignore_unused(i1);
107
108 // i is dereferencable, so it must be incrementable.
109 ++i;
110
111 // how to test for operator-> ?
112 }
113
114 template <class Iterator, class T>
forward_iterator_test(Iterator i,T v1,T v2)115 void forward_iterator_test(Iterator i, T v1, T v2) {
116 input_iterator_test(i, v1, v2);
117
118 Iterator i1 = i, i2 = i;
119
120 BOOST_TEST(i == i1++);
121 BOOST_TEST(i != ++i2);
122
123 trivial_iterator_test(i, i1, v1);
124 trivial_iterator_test(i, i2, v1);
125
126 ++i;
127 BOOST_TEST(i == i1);
128 BOOST_TEST(i == i2);
129 ++i1;
130 ++i2;
131
132 trivial_iterator_test(i, i1, v2);
133 trivial_iterator_test(i, i2, v2);
134
135 typedef typename std::iterator_traits<Iterator>::reference reference;
136 typedef typename std::iterator_traits<Iterator>::value_type value_type;
137 BOOST_TEST(std::is_reference<reference>::value);
138 BOOST_TEST((std::is_same<reference, value_type&>::value ||
139 std::is_same<reference, const value_type&>::value));
140 }
141
142 // Preconditions: *i == v1, *++i == v2
143 template <class Iterator, class T>
bidirectional_iterator_test(Iterator i,T v1,T v2)144 void bidirectional_iterator_test(Iterator i, T v1, T v2) {
145 forward_iterator_test(i, v1, v2);
146 ++i;
147
148 Iterator i1 = i, i2 = i;
149
150 BOOST_TEST(i == i1--);
151 BOOST_TEST(i != --i2);
152
153 trivial_iterator_test(i, i1, v2);
154 trivial_iterator_test(i, i2, v2);
155
156 --i;
157 BOOST_TEST(i == i1);
158 BOOST_TEST(i == i2);
159 ++i1;
160 ++i2;
161
162 trivial_iterator_test(i, i1, v1);
163 trivial_iterator_test(i, i2, v1);
164 }
165
166 // mutable_bidirectional_iterator_test
167
168 template <class U>
169 struct undefined;
170
171 // Preconditions: [i,i+N) is a valid range
172 template <class Iterator, class TrueVals>
random_access_iterator_test(Iterator i,int N,TrueVals vals)173 void random_access_iterator_test(Iterator i, int N, TrueVals vals) {
174 bidirectional_iterator_test(i, vals[0], vals[1]);
175 const Iterator j = i;
176 int c;
177
178 typedef typename std::iterator_traits<Iterator>::value_type value_type;
179 ignore_unused<value_type>();
180
181 for (c = 0; c < N - 1; ++c) {
182 BOOST_TEST(i == j + c);
183 BOOST_TEST(*i == vals[c]);
184 BOOST_TEST(*i == implicit_cast<value_type>(j[c]));
185 BOOST_TEST(*i == *(j + c));
186 BOOST_TEST(*i == *(c + j));
187 ++i;
188 BOOST_TEST(i > j);
189 BOOST_TEST(i >= j);
190 BOOST_TEST(j <= i);
191 BOOST_TEST(j < i);
192 }
193
194 Iterator k = j + N - 1;
195 for (c = 0; c < N - 1; ++c) {
196 BOOST_TEST(i == k - c);
197 BOOST_TEST(*i == vals[N - 1 - c]);
198 BOOST_TEST(*i == implicit_cast<value_type>(j[N - 1 - c]));
199 Iterator q = k - c;
200 ignore_unused(q);
201 BOOST_TEST(*i == *q);
202 BOOST_TEST(i > j);
203 BOOST_TEST(i >= j);
204 BOOST_TEST(j <= i);
205 BOOST_TEST(j < i);
206 --i;
207 }
208 }
209
210 // Precondition: i != j
211 template <class Iterator, class ConstIterator>
const_nonconst_iterator_test(Iterator i,ConstIterator j)212 void const_nonconst_iterator_test(Iterator i, ConstIterator j) {
213 BOOST_TEST(i != j);
214 BOOST_TEST(j != i);
215
216 ConstIterator k(i);
217 BOOST_TEST(k == i);
218 BOOST_TEST(i == k);
219
220 k = i;
221 BOOST_TEST(k == i);
222 BOOST_TEST(i == k);
223 ignore_unused(k);
224 }
225
226 } // namespace histogram
227 } // namespace boost
228
229 #endif // BOOST_HISTOGRAM_TEST_ITERATOR_TESTS_HPP
230