122 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++17, c++2010 11// <ranges>12 13// constexpr auto end();14 15#include <ranges>16 17#include <cassert>18#include <concepts>19#include <functional>20 21#include "test_iterators.h"22 23struct NonCommonRange : std::ranges::view_base {24 using Iterator = forward_iterator<int*>;25 using Sentinel = sentinel_wrapper<Iterator>;26 constexpr explicit NonCommonRange(int* b, int* e) : begin_(b), end_(e) {}27 constexpr Iterator begin() const { return Iterator(begin_); }28 constexpr Sentinel end() const { return Sentinel(Iterator(end_)); }29 30private:31 int* begin_;32 int* end_;33};34 35static_assert(std::ranges::forward_range<NonCommonRange>);36static_assert(!std::ranges::common_range<NonCommonRange>);37 38struct CommonRange : std::ranges::view_base {39 using Iterator = bidirectional_iterator<int*>;40 constexpr explicit CommonRange(int* b, int* e) : begin_(b), end_(e) {}41 constexpr Iterator begin() const { return Iterator(begin_); }42 constexpr Iterator end() const { return Iterator(end_); }43 44private:45 int* begin_;46 int* end_;47};48 49static_assert(std::ranges::bidirectional_range<CommonRange>);50static_assert(std::ranges::common_range<CommonRange>);51 52constexpr bool test() {53 int buff[] = {1, 0, 3, 1, 2, 3, 4, 5};54 55 // Check the return type of `end()`56 {57 CommonRange range(buff, buff + 1);58 auto pred = [](int, int) { return true; };59 std::ranges::chunk_by_view view(range, pred);60 using ChunkByView = decltype(view);61 static_assert(std::ranges::common_range<ChunkByView>);62 ASSERT_SAME_TYPE(std::ranges::sentinel_t<ChunkByView>, decltype(view.end()));63 }64 65 // end() on an empty range66 {67 CommonRange range(buff, buff);68 auto pred = [](int x, int y) { return x <= y; };69 std::ranges::chunk_by_view view(range, pred);70 auto end = view.end();71 assert(end == std::default_sentinel);72 }73 74 // end() on a 1-element range75 {76 CommonRange range(buff, buff + 1);77 auto pred = [](int& x, int& y) { return x <= y; };78 std::ranges::chunk_by_view view(range, pred);79 auto end = view.end();80 assert(base((*--end).begin()) == buff);81 assert(base((*end).end()) == buff + 1);82 }83 84 // end() on a 2-element range85 {86 CommonRange range(buff, buff + 2);87 auto pred = [](int const& x, int const& y) { return x <= y; };88 std::ranges::chunk_by_view view(range, pred);89 auto end = view.end();90 assert(base((*--end).begin()) == buff + 1);91 assert(base((*--end).end()) == buff + 1);92 }93 94 // end() on a 8-element range95 {96 CommonRange range(buff, buff + 8);97 auto pred = [](const int x, const int y) { return x < y; };98 std::ranges::chunk_by_view view(range, pred);99 auto end = view.end();100 assert(base((*--end).end()) == buff + 8);101 assert(base((*--end).end()) == buff + 3);102 }103 104 // end() on a non-common range105 {106 NonCommonRange range(buff, buff + 1);107 std::ranges::chunk_by_view view(range, std::ranges::less_equal{});108 auto end = view.end();109 ASSERT_SAME_TYPE(std::default_sentinel_t, std::ranges::sentinel_t<decltype(view)>);110 ASSERT_SAME_TYPE(std::default_sentinel_t, decltype(end));111 }112 113 return true;114}115 116int main(int, char**) {117 test();118 static_assert(test());119 120 return 0;121}122