119 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// template<range R>12// constexpr range_difference_t<R> ranges::distance(R&& r);13 14#include <iterator>15#include <cassert>16#include <ranges>17 18#include "test_iterators.h"19#include "test_macros.h"20 21template<class It, class Sent>22constexpr void test_ordinary() {23 struct R {24 mutable int a[3] = {1, 2, 3};25 constexpr It begin() const { return It(a); }26 constexpr Sent end() const { return Sent(It(a + 3)); }27 };28 R r;29 assert(std::ranges::distance(r) == 3);30 assert(std::ranges::distance(static_cast<R&&>(r)) == 3);31 assert(std::ranges::distance(static_cast<const R&>(r)) == 3);32 assert(std::ranges::distance(static_cast<const R&&>(r)) == 3);33 ASSERT_SAME_TYPE(decltype(std::ranges::distance(r)), std::ranges::range_difference_t<R>);34}35 36constexpr bool test() {37 {38 using R = int[3];39 int a[] = {1, 2, 3};40 assert(std::ranges::distance(static_cast<R&>(a)) == 3);41 assert(std::ranges::distance(static_cast<R&&>(a)) == 3);42 assert(std::ranges::distance(static_cast<const R&>(a)) == 3);43 assert(std::ranges::distance(static_cast<const R&&>(a)) == 3);44 ASSERT_SAME_TYPE(decltype(std::ranges::distance(a)), std::ptrdiff_t);45 ASSERT_SAME_TYPE(decltype(std::ranges::distance(a)), std::ranges::range_difference_t<R>);46 }47 {48 // Unsized range, non-copyable iterator type, rvalue-ref-qualified begin()49 using It = cpp20_input_iterator<int*>;50 using Sent = sentinel_wrapper<cpp20_input_iterator<int*>>;51 using R = std::ranges::subrange<It, Sent, std::ranges::subrange_kind::unsized>;52 53 int a[] = {1, 2, 3};54 {55 auto r = R(It(a), Sent(It(a + 3)));56 assert(std::ranges::distance(r) == 3);57 }58 {59 auto r = R(It(a), Sent(It(a + 3)));60 assert(std::ranges::distance(static_cast<R&&>(r)) == 3);61 }62 static_assert(!std::is_invocable_v<decltype(std::ranges::distance), const R&>);63 static_assert(!std::is_invocable_v<decltype(std::ranges::distance), const R&&>);64 }65 {66 // Sized range (unsized sentinel type), non-copyable iterator type, rvalue-ref-qualified begin()67 using It = cpp20_input_iterator<int*>;68 using Sent = sentinel_wrapper<cpp20_input_iterator<int*>>;69 using R = std::ranges::subrange<It, Sent, std::ranges::subrange_kind::sized>;70 71 int a[] = {1, 2, 3};72 {73 auto r = R(It(a), Sent(It(a + 3)), 3);74 assert(std::ranges::distance(r) == 3);75 }76 {77 auto r = R(It(a), Sent(It(a + 3)), 3);78 assert(std::ranges::distance(static_cast<R&&>(r)) == 3);79 }80 static_assert(!std::is_invocable_v<decltype(std::ranges::distance), const R&>);81 static_assert(!std::is_invocable_v<decltype(std::ranges::distance), const R&&>);82 }83 {84 // Sized range (sized sentinel type), non-copyable iterator type85 test_ordinary<cpp20_input_iterator<int*>, sized_sentinel<cpp20_input_iterator<int*>>>();86 }87 test_ordinary<cpp17_input_iterator<int*>, sentinel_wrapper<cpp17_input_iterator<int*>>>();88 test_ordinary<cpp20_input_iterator<int*>, sentinel_wrapper<cpp20_input_iterator<int*>>>();89 test_ordinary<cpp17_output_iterator<int*>, sentinel_wrapper<cpp17_output_iterator<int*>>>();90 test_ordinary<forward_iterator<int*>, sentinel_wrapper<forward_iterator<int*>>>();91 test_ordinary<bidirectional_iterator<int*>, sentinel_wrapper<bidirectional_iterator<int*>>>();92 test_ordinary<random_access_iterator<int*>, sentinel_wrapper<random_access_iterator<int*>>>();93 test_ordinary<contiguous_iterator<int*>, sentinel_wrapper<contiguous_iterator<int*>>>();94 test_ordinary<int*, sentinel_wrapper<int*>>();95 96 test_ordinary<cpp17_input_iterator<int*>, sized_sentinel<cpp17_input_iterator<int*>>>();97 test_ordinary<cpp20_input_iterator<int*>, sized_sentinel<cpp20_input_iterator<int*>>>();98 test_ordinary<cpp17_output_iterator<int*>, sized_sentinel<cpp17_output_iterator<int*>>>();99 test_ordinary<forward_iterator<int*>, sized_sentinel<forward_iterator<int*>>>();100 test_ordinary<bidirectional_iterator<int*>, sized_sentinel<bidirectional_iterator<int*>>>();101 test_ordinary<random_access_iterator<int*>, sized_sentinel<random_access_iterator<int*>>>();102 test_ordinary<contiguous_iterator<int*>, sized_sentinel<contiguous_iterator<int*>>>();103 test_ordinary<int*, sized_sentinel<int*>>();104 test_ordinary<int*, int*>();105 106 // Calling it on a non-range isn't allowed.107 static_assert(!std::is_invocable_v<decltype(std::ranges::distance), int>);108 static_assert(!std::is_invocable_v<decltype(std::ranges::distance), int*>);109 110 return true;111}112 113int main(int, char**) {114 test();115 static_assert(test());116 117 return 0;118}119