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// REQUIRES: std-at-least-c++26
10
11// <functional>
12
13// class reference_wrapper
14
15// [refwrap.comparisons], comparisons
16// friend constexpr bool operator==(reference_wrapper, reference_wrapper); // Since C++26
17
18#include <cassert>
19#include <concepts>
20#include <functional>
21
22#include "test_comparisons.h"
23#include "test_macros.h"
24
25// Test SFINAE.
26
27static_assert(HasOperatorEqual<std::reference_wrapper<EqualityComparable>>);
28
29static_assert(!HasOperatorEqual<std::reference_wrapper<NonComparable>>);
30
31// Test equality.
32
33template <typename T>
34constexpr void test() {
35 T i{92};
36 T j{84};
37
38 std::reference_wrapper<T> rw1{i};
39 std::reference_wrapper<T> rw2 = rw1;
40 std::reference_wrapper<T> rw3{j};
41 std::reference_wrapper<const T> crw1{i};
42 std::reference_wrapper<const T> crw3{j};
43
44 AssertEqualityReturnBool<decltype(rw1), decltype(rw2)>();
45 assert(testEquality(rw1, rw2, true));
46 assert(testEquality(rw1, rw3, false));
47}
48
49constexpr bool test() {
50 test<int>();
51 test<EqualityComparable>();
52
53 return true;
54}
55
56int main(int, char**) {
57 test();
58 static_assert(test());
59
60 return 0;
61}
62

source code of libcxx/test/std/utilities/function.objects/refwrap/refwrap.comparissons/equal.refwrap.refwrap.pass.cpp