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, 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(std::equality_comparable_with<std::reference_wrapper<EqualityComparable>,
32 std::reference_wrapper<const EqualityComparable>>);
33
34 static_assert(!std::equality_comparable_with<std::reference_wrapper<EqualityComparable>,
35 std::reference_wrapper<const NonComparable>>);
36
37 // Test equality.
38
39 template <typename T>
test()40 constexpr void test() {
41 T i{92};
42 T j{84};
43
44 std::reference_wrapper<T> rw1{i};
45
46 std::reference_wrapper<T> rw3{j};
47 std::reference_wrapper<const T> crw1{i};
48 std::reference_wrapper<const T> crw3{j};
49
50 AssertEqualityReturnBool<decltype(rw1), decltype(crw1)>();
51 assert(testEquality(rw1, crw1, true));
52 assert(testEquality(rw1, crw3, false));
53 }
54
test()55 constexpr bool test() {
56 test<int>();
57 test<EqualityComparable>();
58
59 return true;
60 }
61
main(int,char **)62 int main(int, char**) {
63 test();
64 static_assert(test());
65
66 return 0;
67 }
68