168 lines · cpp
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-exception6//7//===----------------------------------------------------------------------===//8 9// UNSUPPORTED: c++03, c++11, c++14, c++1710 11// constexpr auto end() requires forward_range<View> && common_range<View>;12// constexpr auto end() const;13 14#include <ranges>15 16#include <cassert>17#include <utility>18#include "test_iterators.h"19#include "test_range.h"20#include "types.h"21 22struct ForwardViewCommonIfConst : std::ranges::view_base {23 std::string_view view_;24 constexpr explicit ForwardViewCommonIfConst() = default;25 constexpr ForwardViewCommonIfConst(const char* ptr) : view_(ptr) {}26 constexpr ForwardViewCommonIfConst(std::string_view v) : view_(v) {}27 constexpr ForwardViewCommonIfConst(ForwardViewCommonIfConst&&) = default;28 constexpr ForwardViewCommonIfConst& operator=(ForwardViewCommonIfConst&&) = default;29 constexpr ForwardViewCommonIfConst(const ForwardViewCommonIfConst&) = default;30 constexpr ForwardViewCommonIfConst& operator=(const ForwardViewCommonIfConst&) = default;31 constexpr forward_iterator<char*> begin() { return forward_iterator<char*>(nullptr); }32 constexpr std::default_sentinel_t end() { return std::default_sentinel; }33 constexpr forward_iterator<std::string_view::const_iterator> begin() const { return forward_iterator<std::string_view::const_iterator>(view_.begin()); }34 constexpr forward_iterator<std::string_view::const_iterator> end() const { return forward_iterator<std::string_view::const_iterator>(view_.end()); }35};36bool operator==(forward_iterator<char*>, std::default_sentinel_t) { return false; }37 38struct ForwardViewNonCommonRange : std::ranges::view_base {39 std::string_view view_;40 constexpr explicit ForwardViewNonCommonRange() = default;41 constexpr ForwardViewNonCommonRange(const char* ptr) : view_(ptr) {}42 constexpr ForwardViewNonCommonRange(std::string_view v) : view_(v) {}43 constexpr ForwardViewNonCommonRange(ForwardViewNonCommonRange&&) = default;44 constexpr ForwardViewNonCommonRange& operator=(ForwardViewNonCommonRange&&) = default;45 constexpr ForwardViewNonCommonRange(const ForwardViewNonCommonRange&) = default;46 constexpr ForwardViewNonCommonRange& operator=(const ForwardViewNonCommonRange&) = default;47 constexpr forward_iterator<char*> begin() { return forward_iterator<char*>(nullptr); }48 constexpr std::default_sentinel_t end() { return std::default_sentinel; }49 constexpr forward_iterator<std::string_view::const_iterator> begin() const { return forward_iterator<std::string_view::const_iterator>(view_.begin()); }50 constexpr std::default_sentinel_t end() const { return std::default_sentinel; }51};52bool operator==(forward_iterator<std::string_view::const_iterator>, std::default_sentinel_t) { return false; }53 54constexpr bool test() {55 // non-const: forward_range<V> && simple_view<V> && simple_view<P> -> outer-iterator<Const = true>56 // const: forward_range<V> && common_range<V> -> outer-iterator<Const = true>57 {58 using V = ForwardView;59 using P = V;60 61 static_assert(std::ranges::forward_range<V>);62 static_assert(std::ranges::common_range<const V>);63 static_assert(simple_view<V>);64 static_assert(simple_view<P>);65 66 {67 std::ranges::lazy_split_view<V, P> v;68 auto it = v.end();69 static_assert(std::is_same_v<decltype(it)::iterator_concept, std::forward_iterator_tag>);70 static_assert(std::is_same_v<decltype(*(*it).begin()), const char&>);71 }72 73 {74 const std::ranges::lazy_split_view<V, P> cv;75 auto it = cv.end();76 static_assert(std::is_same_v<decltype(it)::iterator_concept, std::forward_iterator_tag>);77 static_assert(std::is_same_v<decltype(*(*it).begin()), const char&>);78 }79 }80 81 // non-const: forward_range<V> && common_range<V> && simple_view<V> && !simple_view<P> -> outer-iterator<Const=false>82 // const: forward_range<V> && forward_range<const V> && common_range<const V> -> outer-iterator<Const = false>83 {84 using V = ForwardView;85 using P = ForwardDiffView;86 87 static_assert(std::ranges::forward_range<V>);88 static_assert(std::ranges::common_range<V>);89 static_assert(simple_view<V>);90 static_assert(!simple_view<P>);91 static_assert(std::ranges::forward_range<const V>);92 static_assert(std::ranges::common_range<const V>);93 94 {95 std::ranges::lazy_split_view<V, P> v;96 auto it = v.end();97 static_assert(std::is_same_v<decltype(it)::iterator_concept, std::forward_iterator_tag>);98 static_assert(std::is_same_v<decltype(*(*it).begin()), const char&>);99 }100 101 {102 const std::ranges::lazy_split_view<V, P> cv;103 auto it = cv.end();104 static_assert(std::is_same_v<decltype(it)::iterator_concept, std::forward_iterator_tag>);105 static_assert(std::is_same_v<decltype(*(*it).begin()), const char&>);106 }107 }108 109 // non-const: forward_range<V> && !common_range<V> -> disabled110 // const: forward_range<V> && forward_range<const V> && common_range<const V> -> outer-iterator<Const = true>111 {112 using V = ForwardViewCommonIfConst;113 using P = V;114 115 static_assert(std::ranges::forward_range<V>);116 static_assert(!std::ranges::common_range<V>);117 static_assert(std::ranges::forward_range<const V>);118 static_assert(std::ranges::common_range<const V>);119 120 {121 std::ranges::lazy_split_view<V, P> v;122 auto it = v.begin();123 static_assert(std::is_same_v<decltype(it)::iterator_concept, std::forward_iterator_tag>);124 static_assert(std::is_same_v<decltype(*(*it).begin()), char&>);125 }126 127 {128 const std::ranges::lazy_split_view<V, P> cv;129 auto it = cv.begin();130 static_assert(std::is_same_v<decltype(it)::iterator_concept, std::forward_iterator_tag>);131 static_assert(std::is_same_v<decltype(*(*it).begin()), const char&>);132 }133 }134 135 // non-const: forward_range<V> && !common_range<V> -> disabled136 // const: forward_range<V> && forward_range<const V> && !common_range<const V> -> outer-iterator<Const = false>137 {138 using V = ForwardViewNonCommonRange;139 using P = V;140 141 static_assert(std::ranges::forward_range<V>);142 static_assert(!std::ranges::common_range<V>);143 static_assert(std::ranges::forward_range<const V>);144 static_assert(!std::ranges::common_range<const V>);145 146 {147 std::ranges::lazy_split_view<V, P> v;148 auto it = v.end();149 static_assert(std::same_as<decltype(it), std::default_sentinel_t>);150 }151 152 {153 const std::ranges::lazy_split_view<V, P> cv;154 auto it = cv.end();155 static_assert(std::same_as<decltype(it), std::default_sentinel_t>);156 }157 }158 159 return true;160}161 162int main(int, char**) {163 test();164 static_assert(test());165 166 return 0;167}168