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, c++20, c++23
10 
11 // <functional>
12 
13 // class reference_wrapper
14 
15 // [refwrap.comparisons], comparisons
16 
17 // friend constexpr bool operator==(reference_wrapper, const T&);                                         // Since C++26
18 
19 #include <cassert>
20 #include <concepts>
21 #include <functional>
22 
23 #include "test_comparisons.h"
24 #include "test_macros.h"
25 
26 #include "helper_concepts.h"
27 #include "helper_types.h"
28 
29 // Test SFINAE.
30 
31 static_assert(HasEqualityOperatorWithInt<std::reference_wrapper<EqualityComparable>>);
32 
33 static_assert(!HasEqualityOperatorWithInt<std::reference_wrapper<NonComparable>>);
34 
35 // Test equality.
36 
37 template <typename T>
test()38 constexpr void test() {
39   T i{92};
40   T j{84};
41 
42   std::reference_wrapper<T> rw1{i};
43 
44   // refwrap, const&
45   AssertEqualityReturnBool<decltype(rw1), decltype(i)>();
46   assert(testEquality(rw1, i, true));
47   assert(testEquality(rw1, j, false));
48 }
49 
test()50 constexpr bool test() {
51   test<int>();
52   test<EqualityComparable>();
53 
54   return true;
55 }
56 
main(int,char **)57 int main(int, char**) {
58   test();
59   static_assert(test());
60 
61   return 0;
62 }
63