1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8
9 // UNSUPPORTED: c++03, c++11, c++14, c++17
10
11 // template<input_iterator I, sentinel_for<I> S, class T1, class T2,
12 // output_iterator<const T2&> O, class Proj = identity>
13 // requires indirectly_copyable<I, O> &&
14 // indirect_binary_predicate<ranges::equal_to, projected<I, Proj>, const T1*>
15 // constexpr replace_copy_result<I, O>
16 // replace_copy(I first, S last, O result, const T1& old_value, const T2& new_value,
17 // Proj proj = {}); // Since C++20
18 //
19 // template<input_range R, class T1, class T2, output_iterator<const T2&> O,
20 // class Proj = identity>
21 // requires indirectly_copyable<iterator_t<R>, O> &&
22 // indirect_binary_predicate<ranges::equal_to,
23 // projected<iterator_t<R>, Proj>, const T1*>
24 // constexpr replace_copy_result<borrowed_iterator_t<R>, O>
25 // replace_copy(R&& r, O result, const T1& old_value, const T2& new_value,
26 // Proj proj = {}); // Since C++20
27
28 #include <algorithm>
29 #include <array>
30 #include <concepts>
31 #include <functional>
32 #include <ranges>
33 #include <utility>
34
35 #include "almost_satisfies_types.h"
36 #include "counting_projection.h"
37 #include "test_iterators.h"
38
39 template <class Iter, class Sent = sentinel_wrapper<Iter>, class OutIter = int*>
40 concept HasReplaceCopyIter =
41 requires(Iter&& first, Sent&& last, OutIter&& result) {
42 std::ranges::replace_copy(
43 std::forward<Iter>(first), std::forward<Sent>(last), std::forward<OutIter>(result), 0, 0);
44 };
45
46 static_assert(HasReplaceCopyIter<int*>);
47
48 // !input_iterator<I>
49 static_assert(!HasReplaceCopyIter<InputIteratorNotDerivedFrom>);
50 static_assert(!HasReplaceCopyIter<InputIteratorNotIndirectlyReadable>);
51 static_assert(!HasReplaceCopyIter<InputIteratorNotInputOrOutputIterator>);
52
53 // !sentinel_for<S, I>
54 static_assert(!HasReplaceCopyIter<int*, SentinelForNotSemiregular>);
55 static_assert(!HasReplaceCopyIter<int*, SentinelForNotWeaklyEqualityComparableWith>);
56
57 // !output_iterator<O, const T2&>
58 static_assert(!HasReplaceCopyIter<int*, int*, OutputIteratorNotIndirectlyWritable>);
59 static_assert(!HasReplaceCopyIter<int*, int*, OutputIteratorNotInputOrOutputIterator>);
60
61 // !indirectly_copyable<I, O>
62 static_assert(!HasReplaceCopyIter<int*, int*, int**>);
63
64 // !indirect_binary_predicate<ranges::equal_to, projected<I, Proj>, const T1*>
65 static_assert(!HasReplaceCopyIter<IndirectBinaryPredicateNotIndirectlyReadable>);
66
67 template <class Range, class OutIter = int*>
68 concept HasReplaceCopyRange = requires(Range&& range, OutIter&& result) {
69 std::ranges::replace_copy(std::forward<Range>(range), std::forward<OutIter>(result), 0, 0);
70 };
71
72 template <class T>
73 using R = UncheckedRange<T>;
74
75 static_assert(HasReplaceCopyRange<R<int*>>);
76
77 // !input_range<R>
78 static_assert(!HasReplaceCopyRange<InputRangeNotDerivedFrom>);
79 static_assert(!HasReplaceCopyRange<InputRangeNotIndirectlyReadable>);
80 static_assert(!HasReplaceCopyRange<InputRangeNotInputOrOutputIterator>);
81 static_assert(!HasReplaceCopyRange<InputRangeNotSentinelSemiregular>);
82 static_assert(!HasReplaceCopyRange<InputRangeNotSentinelEqualityComparableWith>);
83
84 // !output_iterator<O, const T2&>
85 static_assert(!HasReplaceCopyRange<R<int*>, OutputIteratorNotIndirectlyWritable>);
86 static_assert(!HasReplaceCopyRange<R<int*>, OutputIteratorNotInputOrOutputIterator>);
87
88 // !indirectly_copyable<iterator_t<R>, O>
89 static_assert(!HasReplaceCopyRange<R<int*>, R<int**>>);
90
91 // !indirect_binary_predicate<ranges::equal_to, projected<iterator_t<T>, Proj>, const T1*>
92 static_assert(!HasReplaceCopyRange<R<IndirectBinaryPredicateNotIndirectlyReadable>>);
93
94 template <int N>
95 struct Data {
96 std::array<int, N> input;
97 int old_value;
98 int new_value;
99 std::array<int, N> expected;
100 };
101
102 template <class InIter, class Sent, class OutIter, int N>
test(Data<N> d)103 constexpr void test(Data<N> d) {
104 { // iterator overload
105 std::array<int, N> output;
106
107 auto first = InIter(d.input.data());
108 auto last = Sent(InIter(d.input.data() + d.input.size()));
109 auto result = OutIter(output.data());
110
111 std::same_as<std::ranges::replace_copy_result<InIter, OutIter>> decltype(auto) ret =
112 std::ranges::replace_copy(std::move(first), std::move(last), std::move(result), d.old_value, d.new_value);
113 assert(base(ret.in) == d.input.data() + d.input.size());
114 assert(base(ret.out) == output.data() + output.size());
115 assert(d.expected == output);
116 }
117
118 { // range overload
119 std::array<int, N> output;
120
121 auto range = std::ranges::subrange(InIter(d.input.data()), Sent(InIter(d.input.data() + d.input.size())));
122 auto result = OutIter(output.data());
123
124 std::same_as<std::ranges::replace_copy_result<InIter, OutIter>> decltype(auto) ret =
125 std::ranges::replace_copy(range, result, d.old_value, d.new_value);
126 assert(base(ret.in) == d.input.data() + d.input.size());
127 assert(base(ret.out) == output.data() + output.size());
128 assert(d.expected == output);
129 }
130 }
131
132 template <class InIter, class Sent, class OutIter>
tests()133 constexpr void tests() {
134 // simple test
135 test<InIter, Sent, OutIter, 4>({.input = {1, 2, 3, 4}, .old_value = 2, .new_value = 5, .expected = {1, 5, 3, 4}});
136 // empty range
137 test<InIter, Sent, OutIter, 0>({.input = {}, .old_value = 2, .new_value = 5, .expected = {}});
138 // all elements match
139 test<InIter, Sent, OutIter, 4>({.input = {1, 1, 1, 1}, .old_value = 1, .new_value = 2, .expected = {2, 2, 2, 2}});
140 // no element matches
141 test<InIter, Sent, OutIter, 4>({.input = {1, 1, 1, 1}, .old_value = 2, .new_value = 3, .expected = {1, 1, 1, 1}});
142 // old_value and new_value are identical - match
143 test<InIter, Sent, OutIter, 4>({.input = {1, 1, 1, 1}, .old_value = 1, .new_value = 1, .expected = {1, 1, 1, 1}});
144 // old_value and new_value are identical - no match
145 test<InIter, Sent, OutIter, 4>({.input = {1, 1, 1, 1}, .old_value = 2, .new_value = 2, .expected = {1, 1, 1, 1}});
146 // more elements
147 test<InIter, Sent, OutIter, 7>(
148 {.input = {1, 2, 3, 4, 5, 6, 7}, .old_value = 2, .new_value = 3, .expected = {1, 3, 3, 4, 5, 6, 7}});
149 // single element - match
150 test<InIter, Sent, OutIter, 1>({.input = {1}, .old_value = 1, .new_value = 5, .expected = {5}});
151 // single element - no match
152 test<InIter, Sent, OutIter, 1>({.input = {2}, .old_value = 1, .new_value = 5, .expected = {2}});
153 }
154
155 template <class InIter, class Sent>
test_output_iterators()156 constexpr void test_output_iterators() {
157 tests<InIter, Sent, cpp17_output_iterator<int*>>();
158 tests<InIter, Sent, forward_iterator<int*>>();
159 tests<InIter, Sent, bidirectional_iterator<int*>>();
160 tests<InIter, Sent, random_access_iterator<int*>>();
161 tests<InIter, Sent, contiguous_iterator<int*>>();
162 tests<InIter, Sent, int*>();
163 }
164
165 template <class InIter>
test_sentinels()166 constexpr void test_sentinels() {
167 test_output_iterators<InIter, InIter>();
168 test_output_iterators<InIter, sentinel_wrapper<InIter>>();
169 test_output_iterators<InIter, sized_sentinel<InIter>>();
170 }
171
test()172 constexpr bool test() {
173 test_output_iterators<cpp17_input_iterator<int*>, sentinel_wrapper<cpp17_input_iterator<int*>>>();
174 test_output_iterators<cpp20_input_iterator<int*>, sentinel_wrapper<cpp20_input_iterator<int*>>>();
175 test_sentinels<forward_iterator<int*>>();
176 test_sentinels<bidirectional_iterator<int*>>();
177 test_sentinels<random_access_iterator<int*>>();
178 test_sentinels<contiguous_iterator<int*>>();
179 test_sentinels<int*>();
180 test_sentinels<const int*>();
181
182 { // check that a custom projection works
183 struct S {
184 int i;
185 };
186
187 { // iterator overload
188 S a[] = {{1}, {2}, {3}, {4}};
189 S b[4];
190 auto ret = std::ranges::replace_copy(std::begin(a), std::end(a), std::begin(b), 1, S{2}, &S::i);
191 assert(ret.in == std::end(a));
192 assert(ret.out == std::end(b));
193 }
194
195 { // range overload
196 S a[] = {{1}, {2}, {3}, {4}};
197 S b[4];
198 auto ret = std::ranges::replace_copy(a, std::begin(b), 1, S{2}, &S::i);
199 assert(ret.in == std::end(a));
200 assert(ret.out == std::end(b));
201 }
202 }
203
204 { // Complexity: exactly `last - first` applications of the corresponding predicate and any projection.
205 { // iterator overload
206 int proj_count = 0;
207 int a[] = {1, 2, 3, 4};
208 int b[4];
209 std::ranges::replace_copy(
210 std::begin(a), std::end(a), std::begin(b), 0, 0, counting_projection(proj_count));
211 assert(proj_count == 4);
212 }
213
214 { // range overload
215 int proj_count = 0;
216 int a[] = {1, 2, 3, 4};
217 int b[4];
218 std::ranges::replace_copy(a, std::begin(b), 0, 0, counting_projection(proj_count));
219 assert(proj_count == 4);
220 }
221 }
222
223 { // using different types for the old and new values works
224 struct S {
225 constexpr operator int() const { return 0; }
226 constexpr bool operator==(const S&) const = default;
227 constexpr bool operator==(int i) const { return i == 0; }
228 };
229 struct T {
230 constexpr operator int() const { return 1; }
231 };
232 {
233 int a[] = {0, 1, 2, 3};
234 int b[4];
235 std::ranges::replace_copy(std::begin(a), std::end(a), std::begin(b), S{}, T{});
236 assert(std::ranges::equal(b, std::array{1, 1, 2, 3}));
237 }
238 {
239 int a[] = {0, 1, 2, 3};
240 int b[4];
241 std::ranges::replace_copy(a, std::begin(b), S{}, T{});
242 assert(std::ranges::equal(b, std::array{1, 1, 2, 3}));
243 }
244 }
245
246 return true;
247 }
248
main(int,char **)249 int main(int, char**) {
250 test();
251 static_assert(test());
252
253 return 0;
254 }
255