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
10 // UNSUPPORTED: libcpp-has-no-incomplete-ranges
11 
12 // friend constexpr bool operator==(const iterator& x, const iterator& y);
13 //          requires ref-is-glvalue && equality_comparable<iterator_t<Base>> &&
14 //                   equality_comparable<iterator_t<range_reference_t<Base>>>;
15 
16 #include <cassert>
17 #include <ranges>
18 
19 #include "../types.h"
20 
21 constexpr bool test() {
22   int buffer[4][4] = {{1, 2, 3, 4}, {5, 6, 7, 8}, {9, 10, 11, 12}, {13, 14, 15, 16}};
23   {
24     std::ranges::join_view jv(buffer);
25     auto iter1 = jv.begin();
26     auto iter2 = jv.begin();
27     assert(iter1 == iter2);
28     iter1++;
29     assert(iter1 != iter2);
30     iter2++;
31     assert(iter1 == iter2);
32 
33     assert(jv.begin() == std::as_const(jv).begin());
34   }
35 
36   {
37     // !ref-is-glvalue
38     BidiCommonInner inners[2] = {buffer[0], buffer[1]};
39     InnerRValue<BidiCommonOuter<BidiCommonInner>> outer{inners};
40     std::ranges::join_view jv(outer);
41     auto iter = jv.begin();
42     static_assert(!std::equality_comparable<decltype(iter)>);
43   }
44 
45   {
46     // !equality_comparable<iterator_t<Base>>
47     using Inner = BufferView<int*>;
48     using Outer = BufferView<cpp20_input_iterator<Inner*>, sentinel_wrapper<cpp20_input_iterator<Inner*>>>;
49     static_assert(!std::equality_comparable<std::ranges::iterator_t<Outer>>);
50     Inner inners[2] = {buffer[0], buffer[1]};
51     std::ranges::join_view jv(Outer{inners});
52     auto iter = jv.begin();
53     static_assert(!std::equality_comparable<decltype(iter)>);
54     auto const_iter = std::as_const(jv).begin();
55     static_assert(!std::equality_comparable<decltype(const_iter)>);
56   }
57 
58   {
59     // !equality_comparable<iterator_t<range_reference_t<Base>>>;
60     using Inner = BufferView<cpp20_input_iterator<int*>, sentinel_wrapper<cpp20_input_iterator<int*>>>;
61     Inner inners[1] = {buffer[0]};
62     std::ranges::join_view jv{inners};
63     auto iter = jv.begin();
64     static_assert(!std::equality_comparable<decltype(iter)>);
65     auto const_iter = std::as_const(jv).begin();
66     static_assert(!std::equality_comparable<decltype(const_iter)>);
67   }
68 
69   return true;
70 }
71 
72 int main(int, char**) {
73   test();
74   static_assert(test());
75 
76   return 0;
77 }
78