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 // <utility>
10
11 // template<ValueType T, size_t N>
12 // requires Swappable<T>
13 // void
14 // swap(T (&a)[N], T (&b)[N]);
15
16 #include <algorithm>
17 #include <cassert>
18 #include <memory>
19 #include <type_traits>
20 #include <utility>
21
22 #include "test_macros.h"
23
24
25 #if TEST_STD_VER >= 11
26 struct CopyOnly {
CopyOnlyCopyOnly27 CopyOnly() {}
CopyOnlyCopyOnly28 CopyOnly(CopyOnly const&) noexcept {}
operator =CopyOnly29 CopyOnly& operator=(CopyOnly const&) { return *this; }
30 };
31
32
33 struct NoexceptMoveOnly {
NoexceptMoveOnlyNoexceptMoveOnly34 NoexceptMoveOnly() {}
NoexceptMoveOnlyNoexceptMoveOnly35 NoexceptMoveOnly(NoexceptMoveOnly&&) noexcept {}
operator =NoexceptMoveOnly36 NoexceptMoveOnly& operator=(NoexceptMoveOnly&&) noexcept { return *this; }
37 };
38
39 struct NotMoveConstructible {
NotMoveConstructibleNotMoveConstructible40 NotMoveConstructible() {}
operator =NotMoveConstructible41 NotMoveConstructible& operator=(NotMoveConstructible&&) { return *this; }
42 private:
43 NotMoveConstructible(NotMoveConstructible&&);
44 };
45
46 template <class Tp>
47 auto can_swap_test(int) -> decltype(std::swap(std::declval<Tp>(), std::declval<Tp>()));
48
49 template <class Tp>
50 auto can_swap_test(...) -> std::false_type;
51
52 template <class Tp>
can_swap()53 constexpr bool can_swap() {
54 return std::is_same<decltype(can_swap_test<Tp>(0)), void>::value;
55 }
56 #endif
57
58 #if TEST_STD_VER > 17
test_swap_constexpr()59 constexpr bool test_swap_constexpr()
60 {
61 int i[3] = {1, 2, 3};
62 int j[3] = {4, 5, 6};
63 std::swap(i, j);
64 return i[0] == 4 &&
65 i[1] == 5 &&
66 i[2] == 6 &&
67 j[0] == 1 &&
68 j[1] == 2 &&
69 j[2] == 3;
70 }
71 #endif // TEST_STD_VER > 17
72
main(int,char **)73 int main(int, char**)
74 {
75 {
76 int i[3] = {1, 2, 3};
77 int j[3] = {4, 5, 6};
78 std::swap(i, j);
79 assert(i[0] == 4);
80 assert(i[1] == 5);
81 assert(i[2] == 6);
82 assert(j[0] == 1);
83 assert(j[1] == 2);
84 assert(j[2] == 3);
85 }
86 #if TEST_STD_VER >= 11
87 {
88 std::unique_ptr<int> i[3];
89 for (int k = 0; k < 3; ++k)
90 i[k].reset(new int(k+1));
91 std::unique_ptr<int> j[3];
92 for (int k = 0; k < 3; ++k)
93 j[k].reset(new int(k+4));
94 std::swap(i, j);
95 assert(*i[0] == 4);
96 assert(*i[1] == 5);
97 assert(*i[2] == 6);
98 assert(*j[0] == 1);
99 assert(*j[1] == 2);
100 assert(*j[2] == 3);
101 }
102 {
103 using CA = CopyOnly[42];
104 using MA = NoexceptMoveOnly[42];
105 using NA = NotMoveConstructible[42];
106 static_assert(can_swap<CA&>(), "");
107 static_assert(can_swap<MA&>(), "");
108 static_assert(!can_swap<NA&>(), "");
109
110 CA ca;
111 MA ma;
112 static_assert(!noexcept(std::swap(ca, ca)), "");
113 static_assert(noexcept(std::swap(ma, ma)), "");
114 }
115 #endif
116
117 #if TEST_STD_VER > 17
118 static_assert(test_swap_constexpr());
119 #endif // TEST_STD_VER > 17
120
121 return 0;
122 }
123