| 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, c++20 |
| 10 | |
| 11 | // friend constexpr void iter_swap(const iterator& l, const iterator& r) noexcept(see below) |
| 12 | // requires (indirectly_swappable<iterator_t<maybe-const<Const, Views>>> && ...); |
| 13 | |
| 14 | #include <array> |
| 15 | #include <cassert> |
| 16 | #include <ranges> |
| 17 | |
| 18 | #include "../types.h" |
| 19 | |
| 20 | struct ThrowingMove { |
| 21 | ThrowingMove() = default; |
| 22 | ThrowingMove(ThrowingMove&&) {} |
| 23 | ThrowingMove& operator=(ThrowingMove&&){return *this;} |
| 24 | }; |
| 25 | |
| 26 | constexpr bool test() { |
| 27 | { |
| 28 | std::array a1{1, 2, 3, 4}; |
| 29 | std::array a2{0.1, 0.2, 0.3}; |
| 30 | std::ranges::zip_view v(a1, a2); |
| 31 | auto iter1 = v.begin(); |
| 32 | auto iter2 = ++v.begin(); |
| 33 | |
| 34 | std::ranges::iter_swap(iter1, iter2); |
| 35 | |
| 36 | assert(a1[0] == 2); |
| 37 | assert(a1[1] == 1); |
| 38 | assert(a2[0] == 0.2); |
| 39 | assert(a2[1] == 0.1); |
| 40 | |
| 41 | auto [x1, y1] = *iter1; |
| 42 | assert(&x1 == &a1[0]); |
| 43 | assert(&y1 == &a2[0]); |
| 44 | |
| 45 | auto [x2, y2] = *iter2; |
| 46 | assert(&x2 == &a1[1]); |
| 47 | assert(&y2 == &a2[1]); |
| 48 | |
| 49 | static_assert(noexcept(std::ranges::iter_swap(iter1, iter2))); |
| 50 | } |
| 51 | |
| 52 | { |
| 53 | // underlying iter_swap may throw |
| 54 | std::array<ThrowingMove, 2> iterSwapMayThrow{}; |
| 55 | std::ranges::zip_view v(iterSwapMayThrow); |
| 56 | auto iter1 = v.begin(); |
| 57 | auto iter2 = ++v.begin(); |
| 58 | static_assert(!noexcept(std::ranges::iter_swap(iter1, iter2))); |
| 59 | } |
| 60 | |
| 61 | { |
| 62 | // underlying iterators' iter_move are called through ranges::iter_swap |
| 63 | adltest::IterMoveSwapRange r1, r2; |
| 64 | assert(r1.iter_swap_called_times == 0); |
| 65 | assert(r2.iter_swap_called_times == 0); |
| 66 | |
| 67 | std::ranges::zip_view v{r1, r2}; |
| 68 | auto it1 = v.begin(); |
| 69 | auto it2 = std::ranges::next(it1, 3); |
| 70 | |
| 71 | std::ranges::iter_swap(it1, it2); |
| 72 | assert(r1.iter_swap_called_times == 2); |
| 73 | assert(r2.iter_swap_called_times == 2); |
| 74 | |
| 75 | std::ranges::iter_swap(it1, it2); |
| 76 | assert(r1.iter_swap_called_times == 4); |
| 77 | assert(r2.iter_swap_called_times == 4); |
| 78 | } |
| 79 | return true; |
| 80 | } |
| 81 | |
| 82 | int main(int, char**) { |
| 83 | test(); |
| 84 | static_assert(test()); |
| 85 | |
| 86 | return 0; |
| 87 | } |
| 88 | |