| 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> |
| 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> |
| 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> |
| 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> |
| 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 | |
| 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[] = {{.i: 1}, {.i: 2}, {.i: 3}, {.i: 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(arr&: a)); |
| 192 | assert(ret.out == std::end(arr&: b)); |
| 193 | } |
| 194 | |
| 195 | { // range overload |
| 196 | S a[] = {{.i: 1}, {.i: 2}, {.i: 3}, {.i: 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(arr&: a)); |
| 200 | assert(ret.out == std::end(arr&: 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 | |
| 249 | int main(int, char**) { |
| 250 | test(); |
| 251 | static_assert(test()); |
| 252 | |
| 253 | return 0; |
| 254 | } |
| 255 | |