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 // <algorithm> 10 11 // UNSUPPORTED: c++03, c++11, c++14, c++17 12 13 // template<input_iterator I, sentinel_for<I> S, weakly_incrementable O> 14 // requires indirectly_copyable<I, O> 15 // constexpr ranges::copy_result<I, O> ranges::copy(I first, S last, O result); 16 // template<input_range R, weakly_incrementable O> 17 // requires indirectly_copyable<iterator_t<R>, O> 18 // constexpr ranges::copy_result<borrowed_iterator_t<R>, O> ranges::copy(R&& r, O result); 19 20 #include <algorithm> 21 #include <array> 22 #include <cassert> 23 #include <deque> 24 #include <ranges> 25 #include <vector> 26 27 #include "almost_satisfies_types.h" 28 #include "test_iterators.h" 29 #include "type_algorithms.h" 30 31 template <class In, class Out = In, class Sent = sentinel_wrapper<In>> 32 concept HasCopyIt = requires(In in, Sent sent, Out out) { std::ranges::copy(in, sent, out); }; 33 34 static_assert(HasCopyIt<int*>); 35 static_assert(!HasCopyIt<InputIteratorNotDerivedFrom>); 36 static_assert(!HasCopyIt<InputIteratorNotIndirectlyReadable>); 37 static_assert(!HasCopyIt<InputIteratorNotInputOrOutputIterator>); 38 static_assert(!HasCopyIt<int*, WeaklyIncrementableNotMovable>); 39 struct NotIndirectlyCopyable {}; 40 static_assert(!HasCopyIt<int*, NotIndirectlyCopyable*>); 41 static_assert(!HasCopyIt<int*, int*, SentinelForNotSemiregular>); 42 static_assert(!HasCopyIt<int*, int*, SentinelForNotWeaklyEqualityComparableWith>); 43 44 template <class Range, class Out> 45 concept HasCopyR = requires(Range range, Out out) { std::ranges::copy(range, out); }; 46 47 static_assert(HasCopyR<std::array<int, 10>, int*>); 48 static_assert(!HasCopyR<InputRangeNotDerivedFrom, int*>); 49 static_assert(!HasCopyR<InputRangeNotIndirectlyReadable, int*>); 50 static_assert(!HasCopyR<InputRangeNotInputOrOutputIterator, int*>); 51 static_assert(!HasCopyR<WeaklyIncrementableNotMovable, int*>); 52 static_assert(!HasCopyR<UncheckedRange<NotIndirectlyCopyable*>, int*>); 53 static_assert(!HasCopyR<InputRangeNotSentinelSemiregular, int*>); 54 static_assert(!HasCopyR<InputRangeNotSentinelEqualityComparableWith, int*>); 55 56 static_assert(std::is_same_v<std::ranges::copy_result<int, long>, std::ranges::in_out_result<int, long>>); 57 58 // clang-format off 59 template <class In, class Out, class Sent = In> 60 constexpr void test_iterators() { 61 { // simple test 62 { 63 std::array in{1, 2, 3, 4}; 64 std::array<int, 4> out; 65 std::same_as<std::ranges::in_out_result<In, Out>> auto ret = 66 std::ranges::copy(In(in.data()), Sent(In(in.data() + in.size())), Out(out.data())); 67 assert(in == out); 68 assert(base(ret.in) == in.data() + in.size()); 69 assert(base(ret.out) == out.data() + out.size()); 70 } 71 { 72 std::array in{1, 2, 3, 4}; 73 std::array<int, 4> out; 74 auto range = std::ranges::subrange(In(in.data()), Sent(In(in.data() + in.size()))); 75 std::same_as<std::ranges::in_out_result<In, Out>> auto ret = std::ranges::copy(range, Out(out.data())); 76 assert(in == out); 77 assert(base(ret.in) == in.data() + in.size()); 78 assert(base(ret.out) == out.data() + out.size()); 79 } 80 } 81 82 { // check that an empty range works 83 { 84 std::array<int, 0> in; 85 std::array<int, 0> out; 86 auto ret = std::ranges::copy(In(in.data()), Sent(In(in.data() + in.size())), Out(out.data())); 87 assert(base(ret.in) == in.data()); 88 assert(base(ret.out) == out.data()); 89 } 90 { 91 std::array<int, 0> in; 92 std::array<int, 0> out; 93 auto range = std::ranges::subrange(In(in.data()), Sent(In(in.data() + in.size()))); 94 auto ret = std::ranges::copy(range, Out(out.data())); 95 assert(base(ret.in) == in.data()); 96 assert(base(ret.out) == out.data()); 97 } 98 } 99 } 100 // clang-format on 101 102 constexpr bool test() { 103 meta::for_each(meta::forward_iterator_list<int*>{}, []<class Out>() { 104 test_iterators<cpp20_input_iterator<int*>, Out, sentinel_wrapper<cpp20_input_iterator<int*>>>(); 105 test_iterators<ProxyIterator<cpp20_input_iterator<int*>>, 106 ProxyIterator<Out>, 107 sentinel_wrapper<ProxyIterator<cpp20_input_iterator<int*>>>>(); 108 109 meta::for_each(meta::forward_iterator_list<int*>{}, []<class In>() { 110 test_iterators<In, Out>(); 111 test_iterators<In, Out, sized_sentinel<In>>(); 112 test_iterators<In, Out, sentinel_wrapper<In>>(); 113 114 test_iterators<ProxyIterator<In>, ProxyIterator<Out>>(); 115 test_iterators<ProxyIterator<In>, ProxyIterator<Out>, sized_sentinel<ProxyIterator<In>>>(); 116 test_iterators<ProxyIterator<In>, ProxyIterator<Out>, sentinel_wrapper<ProxyIterator<In>>>(); 117 }); 118 }); 119 120 { // check that ranges::dangling is returned 121 std::array<int, 4> out; 122 std::same_as<std::ranges::in_out_result<std::ranges::dangling, int*>> auto ret = 123 std::ranges::copy(std::array{1, 2, 3, 4}, out.data()); 124 assert(ret.out == out.data() + 4); 125 assert((out == std::array{1, 2, 3, 4})); 126 } 127 128 { // check that an iterator is returned with a borrowing range 129 std::array in{1, 2, 3, 4}; 130 std::array<int, 4> out; 131 std::same_as<std::ranges::in_out_result<int*, int*>> auto ret = std::ranges::copy(std::views::all(in), out.data()); 132 assert(ret.in == in.data() + 4); 133 assert(ret.out == out.data() + 4); 134 assert(in == out); 135 } 136 137 { // check that every element is copied exactly once 138 struct CopyOnce { 139 bool copied = false; 140 constexpr CopyOnce() = default; 141 constexpr CopyOnce(const CopyOnce& other) = delete; 142 constexpr CopyOnce& operator=(const CopyOnce& other) { 143 assert(!other.copied); 144 copied = true; 145 return *this; 146 } 147 }; 148 { 149 std::array<CopyOnce, 4> in{}; 150 std::array<CopyOnce, 4> out{}; 151 auto ret = std::ranges::copy(in.begin(), in.end(), out.begin()); 152 assert(ret.in == in.end()); 153 assert(ret.out == out.end()); 154 assert(std::all_of(out.begin(), out.end(), [](const auto& e) { return e.copied; })); 155 } 156 { 157 std::array<CopyOnce, 4> in{}; 158 std::array<CopyOnce, 4> out{}; 159 auto ret = std::ranges::copy(in, out.begin()); 160 assert(ret.in == in.end()); 161 assert(ret.out == out.end()); 162 assert(std::all_of(out.begin(), out.end(), [](const auto& e) { return e.copied; })); 163 } 164 } 165 166 { // check that the range is copied forwards 167 struct OnlyForwardsCopyable { 168 OnlyForwardsCopyable* next = nullptr; 169 bool canCopy = false; 170 OnlyForwardsCopyable() = default; 171 constexpr OnlyForwardsCopyable& operator=(const OnlyForwardsCopyable&) { 172 assert(canCopy); 173 if (next != nullptr) 174 next->canCopy = true; 175 return *this; 176 } 177 }; 178 { 179 std::array<OnlyForwardsCopyable, 3> in{}; 180 std::array<OnlyForwardsCopyable, 3> out{}; 181 out[0].next = &out[1]; 182 out[1].next = &out[2]; 183 out[0].canCopy = true; 184 auto ret = std::ranges::copy(in.begin(), in.end(), out.begin()); 185 assert(ret.in == in.end()); 186 assert(ret.out == out.end()); 187 assert(out[0].canCopy); 188 assert(out[1].canCopy); 189 assert(out[2].canCopy); 190 } 191 { 192 std::array<OnlyForwardsCopyable, 3> in{}; 193 std::array<OnlyForwardsCopyable, 3> out{}; 194 out[0].next = &out[1]; 195 out[1].next = &out[2]; 196 out[0].canCopy = true; 197 auto ret = std::ranges::copy(in, out.begin()); 198 assert(ret.in == in.end()); 199 assert(ret.out == out.end()); 200 assert(out[0].canCopy); 201 assert(out[1].canCopy); 202 assert(out[2].canCopy); 203 } 204 } 205 206 return true; 207 } 208 209 int main(int, char**) { 210 test(); 211 static_assert(test()); 212 213 return 0; 214 } 215