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// 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#include "helper_concepts.h"
26#include "helper_types.h"
27
28// Test SFINAE.
29
30static_assert(std::equality_comparable<std::reference_wrapper<EqualityComparable>>);
31
32static_assert(!std::equality_comparable<std::reference_wrapper<NonComparable>>);
33
34// Test equality.
35
36template <typename T>
37constexpr void test() {
38 T i{92};
39 T j{84};
40
41 std::reference_wrapper<T> rw1{i};
42 std::reference_wrapper<T> rw2 = rw1;
43 std::reference_wrapper<T> rw3{j};
44 std::reference_wrapper<const T> crw1{i};
45 std::reference_wrapper<const T> crw3{j};
46
47 AssertEqualityReturnBool<decltype(rw1), decltype(rw2)>();
48 assert(testEquality(rw1, rw2, true));
49 assert(testEquality(rw1, rw3, false));
50}
51
52constexpr bool test() {
53 test<int>();
54 test<EqualityComparable>();
55
56 return true;
57}
58
59int main(int, char**) {
60 test();
61 static_assert(test());
62
63 return 0;
64}
65

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