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 
11 // friend constexpr bool operator==(const outer-iterator& x, const outer-iterator& y)
12 //   requires forward_range<Base>;
13 //
14 // friend constexpr bool operator==(const outer-iterator& x, default_sentinel_t);
15 
16 #include <ranges>
17 
18 #include <concepts>
19 #include <string_view>
20 
21 #include "../types.h"
22 
23 #include "test_range.h"
24 
test()25 constexpr bool test() {
26   // Forward range supports both overloads of `operator==`.
27   {
28     // outer-iterator == outer-iterator
29     {
30       SplitViewForward v("abc def", " ");
31       auto b = v.begin(), e = v.end();
32 
33       assert(b == b);
34       assert(!(b != b));
35 
36       assert(e == e);
37       assert(!(e != e));
38 
39       assert(!(b == e));
40       assert(b != e);
41     }
42 
43     // outer-iterator == default_sentinel
44     {
45       SplitViewForward v("abc def", " ");
46       auto b = v.begin(), e = v.end();
47 
48       assert(!(b == std::default_sentinel));
49       assert(b != std::default_sentinel);
50       assert(e == std::default_sentinel);
51       assert(!(e != std::default_sentinel));
52     }
53 
54       // Default-constructed `outer-iterator`s compare equal.
55       {
56         OuterIterForward i1, i2;
57         assert(i1 == i2);
58         assert(!(i1 != i2));
59       }
60   }
61 
62   // Input range only supports comparing an `outer-iterator` to the default sentinel.
63   {
64     using namespace std::string_view_literals;
65     SplitViewInput v("abc def"sv, ' ');
66     auto b = v.begin();
67     std::same_as<std::default_sentinel_t> decltype(auto) e = v.end();
68 
69     static_assert(!weakly_equality_comparable_with<decltype(b), decltype(b)>);
70 
71     assert(!(b == std::default_sentinel));
72     assert(b != std::default_sentinel);
73     assert(!(b == e));
74     assert(b != e);
75   }
76 
77   return true;
78 }
79 
main(int,char **)80 int main(int, char**) {
81   test();
82   static_assert(test());
83 
84   return 0;
85 }
86