110 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 chunk_by_view(View, Pred);14 15#include <ranges>16 17#include <algorithm>18#include <array>19#include <cassert>20#include <utility>21 22#include "types.h"23 24struct Range : std::ranges::view_base {25 constexpr explicit Range(int* b, int* e) : begin_(b), end_(e) {}26 constexpr int* begin() const { return begin_; }27 constexpr int* end() const { return end_; }28 29private:30 int* begin_;31 int* end_;32};33 34static_assert(std::ranges::view<Range>);35static_assert(std::ranges::forward_range<Range>);36 37struct Pred {38 constexpr bool operator()(int x, int y) const { return x <= y; }39};40 41struct TrackingPred : TrackInitialization {42 using TrackInitialization::TrackInitialization;43 constexpr bool operator()(int&, int&) const;44};45 46struct TrackingRange : TrackInitialization, std::ranges::view_base {47 using TrackInitialization::TrackInitialization;48 int* begin() const;49 int* end() const;50};51 52template <class T>53void implicitConstructionTest(T);54 55template <class T, class... Args>56concept ImplicitConstructibleFrom =57 requires(Args&&... args) { implicitConstructionTest({std::forward<Args>(args)...}); };58 59constexpr bool test() {60 int buff[] = {1, 2, 3, 0, 1, 2, -1, -1, 0};61 62 // Test explicit syntax63 {64 Range range(buff, buff + 9);65 Pred pred;66 std::ranges::chunk_by_view<Range, Pred> view(range, pred);67 auto it = view.begin(), end = view.end();68 assert(std::ranges::equal(*it++, std::array{1, 2, 3}));69 assert(std::ranges::equal(*it++, std::array{0, 1, 2}));70 assert(std::ranges::equal(*it++, std::array{-1, -1, 0}));71 assert(it == end);72 }73 74 // Test implicit syntax75 {76 using ChunkByView = std::ranges::chunk_by_view<Range, Pred>;77 static_assert(!ImplicitConstructibleFrom<ChunkByView, Range, Pred>);78 static_assert(!ImplicitConstructibleFrom<ChunkByView, const Range&, const Pred&>);79 }80 81 // Make sure we move the view82 {83 bool moved = false, copied = false;84 TrackingRange range(&moved, &copied);85 Pred pred;86 [[maybe_unused]] std::ranges::chunk_by_view<TrackingRange, Pred> view(std::move(range), pred);87 assert(moved);88 assert(!copied);89 }90 91 // Make sure we move the predicate92 {93 bool moved = false, copied = false;94 Range range(buff, buff + 9);95 TrackingPred pred(&moved, &copied);96 [[maybe_unused]] std::ranges::chunk_by_view<Range, TrackingPred> view(range, std::move(pred));97 assert(moved);98 assert(!copied);99 }100 101 return true;102}103 104int main(int, char**) {105 test();106 static_assert(test());107 108 return 0;109}110