| 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 | // constexpr sentinel(sentinel<!Const> s); |
| 12 | |
| 13 | #include <cassert> |
| 14 | #include <ranges> |
| 15 | |
| 16 | #include "../types.h" |
| 17 | |
| 18 | template <class T> |
| 19 | struct convertible_sentinel_wrapper { |
| 20 | explicit convertible_sentinel_wrapper() = default; |
| 21 | constexpr convertible_sentinel_wrapper(const T& it) : it_(it) {} |
| 22 | |
| 23 | template <class U> |
| 24 | requires std::convertible_to<const U&, T> |
| 25 | constexpr convertible_sentinel_wrapper(const convertible_sentinel_wrapper<U>& other) : it_(other.it_) {} |
| 26 | |
| 27 | constexpr friend bool operator==(convertible_sentinel_wrapper const& self, const T& other) { |
| 28 | return self.it_ == other; |
| 29 | } |
| 30 | T it_; |
| 31 | }; |
| 32 | |
| 33 | struct NonSimpleNonCommonConvertibleView : IntBufferView { |
| 34 | using IntBufferView::IntBufferView; |
| 35 | |
| 36 | constexpr int* begin() { return buffer_; } |
| 37 | constexpr const int* begin() const { return buffer_; } |
| 38 | constexpr convertible_sentinel_wrapper<int*> end() { return convertible_sentinel_wrapper<int*>(buffer_ + size_); } |
| 39 | constexpr convertible_sentinel_wrapper<const int*> end() const { |
| 40 | return convertible_sentinel_wrapper<const int*>(buffer_ + size_); |
| 41 | } |
| 42 | }; |
| 43 | |
| 44 | static_assert(!std::ranges::common_range<NonSimpleNonCommonConvertibleView>); |
| 45 | static_assert(std::ranges::random_access_range<NonSimpleNonCommonConvertibleView>); |
| 46 | static_assert(!std::ranges::sized_range<NonSimpleNonCommonConvertibleView>); |
| 47 | static_assert(std::convertible_to<std::ranges::sentinel_t<NonSimpleNonCommonConvertibleView>, |
| 48 | std::ranges::sentinel_t<NonSimpleNonCommonConvertibleView const>>); |
| 49 | static_assert(!simple_view<NonSimpleNonCommonConvertibleView>); |
| 50 | |
| 51 | constexpr bool test() { |
| 52 | int buffer1[4] = {1, 2, 3, 4}; |
| 53 | int buffer2[5] = {1, 2, 3, 4, 5}; |
| 54 | std::ranges::zip_view v{NonSimpleNonCommonConvertibleView(buffer1), NonSimpleNonCommonConvertibleView(buffer2)}; |
| 55 | static_assert(!std::ranges::common_range<decltype(v)>); |
| 56 | auto sent1 = v.end(); |
| 57 | std::ranges::sentinel_t<const decltype(v)> sent2 = sent1; |
| 58 | static_assert(!std::is_same_v<decltype(sent1), decltype(sent2)>); |
| 59 | |
| 60 | assert(v.begin() != sent2); |
| 61 | assert(std::as_const(v).begin() != sent2); |
| 62 | assert(v.begin() + 4 == sent2); |
| 63 | assert(std::as_const(v).begin() + 4 == sent2); |
| 64 | |
| 65 | // Cannot create a non-const iterator from a const iterator. |
| 66 | static_assert(!std::constructible_from<decltype(sent1), decltype(sent2)>); |
| 67 | return true; |
| 68 | } |
| 69 | |
| 70 | int main(int, char**) { |
| 71 | test(); |
| 72 | static_assert(test()); |
| 73 | |
| 74 | return 0; |
| 75 | } |
| 76 | |