1// Boost.Range library
2//
3// Copyright Neil Groves 2009. Use, modification and
4// distribution is subject to the Boost Software License, Version
5// 1.0. (See accompanying file LICENSE_1_0.txt or copy at
6// http://www.boost.org/LICENSE_1_0.txt)
7//
8//
9// For more information, see http://www.boost.org/libs/range/
10//
11// The strided_defect_Trac5014 test case is a modified version of a test case
12// contributed by Maxim Yanchenko as part of the trac ticket.
13//
14// The deque test case has been removed due to erroneous standard library
15// implementations causing test failures.
16//
17#include <boost/range/adaptor/strided.hpp>
18
19#include <boost/config.hpp>
20#include <boost/test/test_tools.hpp>
21#include <boost/test/unit_test.hpp>
22
23#include <boost/assign.hpp>
24#include <boost/range/algorithm_ext.hpp>
25
26#include <algorithm>
27#include <vector>
28
29namespace boost
30{
31 namespace
32 {
33 template< class Container >
34 void strided_test_impl( Container& c, int stride_size )
35 {
36 using namespace boost::adaptors;
37
38 // Rationale:
39 // This requirement was too restrictive. It makes the use of the
40 // strided adaptor too dangerous, and a simple solution existed
41 // to make it safe, hence the strided adaptor has been modified
42 // and this restriction no longer applies.
43 //BOOST_ASSERT( c.size() % STRIDE_SIZE == 0 );
44
45 Container reference;
46
47 {
48 typedef BOOST_DEDUCED_TYPENAME Container::const_iterator
49 iterator_t BOOST_RANGE_UNUSED;
50 typedef BOOST_DEDUCED_TYPENAME Container::difference_type
51 diff_t BOOST_RANGE_UNUSED;
52 typedef BOOST_DEDUCED_TYPENAME Container::size_type
53 size_type BOOST_RANGE_UNUSED;
54 iterator_t it = c.begin();
55
56 iterator_t last = c.end();
57 for (; it != last; )
58 {
59 reference.push_back(*it);
60
61 for (int i = 0; (it != last) && (i < stride_size); ++i)
62 ++it;
63 }
64 }
65
66 Container test;
67 boost::push_back( test, c | strided(stride_size) );
68
69 BOOST_CHECK_EQUAL_COLLECTIONS( test.begin(), test.end(),
70 reference.begin(), reference.end() );
71
72 Container test2;
73 boost::push_back( test2, adaptors::stride(c, stride_size) );
74
75 BOOST_CHECK_EQUAL_COLLECTIONS( test2.begin(), test2.end(),
76 reference.begin(), reference.end() );
77
78 // Test the const versions:
79 const Container& cc = c;
80 Container test3;
81 boost::push_back( test3, cc | strided(stride_size) );
82
83 BOOST_CHECK_EQUAL_COLLECTIONS( test3.begin(), test3.end(),
84 reference.begin(), reference.end() );
85
86 Container test4;
87 boost::push_back( test4, adaptors::stride(cc, stride_size) );
88
89 BOOST_CHECK_EQUAL_COLLECTIONS( test4.begin(), test4.end(),
90 reference.begin(), reference.end() );
91 }
92
93 template< class Container >
94 void strided_test_impl(int stride_size)
95 {
96 using namespace boost::assign;
97
98 Container c;
99
100 // Test empty
101 strided_test_impl(c, stride_size);
102
103 // Test two elements
104 c += 1,2;
105 strided_test_impl(c, stride_size);
106
107 // Test many elements
108 c += 1,1,1,2,2,3,4,5,6,6,6,7,8,9;
109 strided_test_impl(c, stride_size);
110
111 // Test an odd number of elements to determine that the relaxation
112 // of the requirements has been successful
113 // Test a sequence of length 1 with a stride of 2
114 c.clear();
115 c += 1;
116 strided_test_impl(c, stride_size);
117
118 // Test a sequence of length 2 with a stride of 2
119 c.clear();
120 c += 1,2;
121 strided_test_impl(c, stride_size);
122
123 // Test a sequence of length 3 with a stride of 2
124 c.clear();
125 c += 1,2,3;
126 strided_test_impl(c, stride_size);
127 }
128
129 template<typename Container>
130 void strided_test_zero_stride()
131 {
132 Container c;
133 c.push_back(1);
134
135 typedef boost::strided_range<Container> strided_range_t;
136 strided_range_t rng( boost::adaptors::stride(c, 0) );
137 boost::ignore_unused_variable_warning(rng);
138 typedef BOOST_DEDUCED_TYPENAME boost::range_iterator<strided_range_t>::type iter_t;
139
140 typedef BOOST_DEDUCED_TYPENAME boost::iterator_traversal<
141 BOOST_DEDUCED_TYPENAME Container::const_iterator
142 >::type container_traversal_tag;
143
144 iter_t first = boost::range_detail::make_begin_strided_iterator(
145 c, 0, container_traversal_tag());
146
147 iter_t last = boost::range_detail::make_end_strided_iterator(
148 c, 0, container_traversal_tag());
149
150 iter_t it = first;
151 for (int i = 0; i < 10; ++i, ++it)
152 {
153 BOOST_CHECK(it == first);
154 }
155 }
156
157 template<typename Container>
158 void strided_test_impl()
159 {
160 strided_test_zero_stride< Container >();
161
162 const int MAX_STRIDE_SIZE = 10;
163 for (int stride_size = 1; stride_size <= MAX_STRIDE_SIZE; ++stride_size)
164 {
165 strided_test_impl< Container >(stride_size);
166 }
167 }
168
169 void strided_test()
170 {
171 strided_test_impl< std::vector<int> >();
172 strided_test_impl< std::list<int> >();
173 }
174
175 void strided_defect_Trac5014()
176 {
177 using namespace boost::assign;
178
179 std::vector<int> v;
180 for (int i = 0; i < 30; ++i)
181 v.push_back(x: i);
182
183 std::vector<int> reference;
184 reference += 0,4,8,12,16,20,24,28;
185
186 std::vector<int> output;
187 boost::push_back(on&: output, from: v | boost::adaptors::strided(4));
188
189 BOOST_CHECK_EQUAL_COLLECTIONS( reference.begin(), reference.end(),
190 output.begin(), output.end() );
191
192 BOOST_CHECK_EQUAL( output.back(), 28 );
193 }
194
195 template<typename BaseIterator, typename Category>
196 class strided_mock_iterator
197 : public boost::iterator_adaptor<
198 strided_mock_iterator<BaseIterator,Category>
199 , BaseIterator
200 , boost::use_default
201 , Category
202 >
203 {
204 typedef boost::iterator_adaptor<
205 strided_mock_iterator
206 , BaseIterator
207 , boost::use_default
208 , Category
209 > super_t;
210 public:
211 explicit strided_mock_iterator(BaseIterator it)
212 : super_t(it)
213 {
214 }
215
216 private:
217 void increment()
218 {
219 ++(this->base_reference());
220 }
221
222 friend class boost::iterator_core_access;
223 };
224
225 template<typename Category, typename Range>
226 boost::iterator_range<strided_mock_iterator<BOOST_DEDUCED_TYPENAME boost::range_iterator<Range>::type, Category> >
227 as_mock_range(Range& rng)
228 {
229 typedef BOOST_DEDUCED_TYPENAME boost::range_iterator<Range>::type range_iter_t;
230 typedef strided_mock_iterator<range_iter_t, Category> mock_iter_t;
231
232 return boost::iterator_range<mock_iter_t>(
233 mock_iter_t(boost::begin(rng)),
234 mock_iter_t(boost::end(rng)));
235 }
236
237 void strided_test_traversal()
238 {
239 using namespace boost::assign;
240
241 std::vector<int> v;
242 for (int i = 0; i < 30; ++i)
243 v.push_back(x: i);
244
245 std::vector<int> reference;
246 reference += 0,4,8,12,16,20,24,28;
247
248 std::vector<int> output;
249 boost::push_back(on&: output, from: as_mock_range<boost::forward_traversal_tag>(rng&: v) | boost::adaptors::strided(4));
250
251 BOOST_CHECK_EQUAL_COLLECTIONS( reference.begin(), reference.end(),
252 output.begin(), output.end() );
253
254 output.clear();
255 boost::push_back(on&: output, from: as_mock_range<boost::bidirectional_traversal_tag>(rng&: v) | boost::adaptors::strided(4));
256
257 BOOST_CHECK_EQUAL_COLLECTIONS( reference.begin(), reference.end(),
258 output.begin(), output.end() );
259
260 output.clear();
261 boost::push_back(on&: output, from: as_mock_range<boost::random_access_traversal_tag>(rng&: v) | boost::adaptors::strided(4));
262
263 BOOST_CHECK_EQUAL_COLLECTIONS( reference.begin(), reference.end(),
264 output.begin(), output.end() );
265 }
266
267 template<typename Range>
268 void strided_test_ticket_5236_check_bidirectional(const Range& rng)
269 {
270 BOOST_CHECK_EQUAL( boost::distance(rng), 1 );
271 BOOST_CHECK_EQUAL( std::distance(boost::begin(rng), boost::prior(boost::end(rng))), 0 );
272 }
273
274 template<typename Range>
275 void strided_test_ticket_5236_check(const Range& rng)
276 {
277 strided_test_ticket_5236_check_bidirectional(rng);
278
279 typename boost::range_iterator<const Range>::type it = boost::end(rng);
280 it = it - 1;
281 BOOST_CHECK_EQUAL( std::distance(boost::begin(rng), it), 0 );
282 }
283
284 void strided_test_ticket_5236()
285 {
286 std::vector<int> v;
287 v.push_back(x: 1);
288 strided_test_ticket_5236_check( rng: v | boost::adaptors::strided(2) );
289
290 // Ensure that there is consistency between the random-access implementation
291 // and the bidirectional.
292
293 std::list<int> l;
294 l.push_back(x: 1);
295 strided_test_ticket_5236_check_bidirectional( rng: l | boost::adaptors::strided(2) );
296 }
297
298 }
299}
300
301boost::unit_test::test_suite*
302init_unit_test_suite(int argc, char* argv[])
303{
304 boost::unit_test::test_suite* test
305 = BOOST_TEST_SUITE( "RangeTestSuite.adaptor.strided" );
306
307 test->add( BOOST_TEST_CASE( &boost::strided_test ) );
308 test->add( BOOST_TEST_CASE( &boost::strided_defect_Trac5014 ) );
309 test->add( BOOST_TEST_CASE( &boost::strided_test_traversal ) );
310 test->add( BOOST_TEST_CASE( &boost::strided_test_ticket_5236 ) );
311
312 return test;
313}
314

source code of boost/libs/range/test/adaptor_test/strided.cpp