| 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 | // test move |
| 10 | |
| 11 | #include <utility> |
| 12 | #include <type_traits> |
| 13 | #include <cassert> |
| 14 | |
| 15 | #include "test_macros.h" |
| 16 | |
| 17 | class move_only |
| 18 | { |
| 19 | move_only(const move_only&); |
| 20 | move_only& operator=(const move_only&); |
| 21 | public: |
| 22 | move_only(move_only&&) {} |
| 23 | move_only& operator=(move_only&&) {return *this;} |
| 24 | |
| 25 | move_only() {} |
| 26 | }; |
| 27 | |
| 28 | move_only source() {return move_only();} |
| 29 | const move_only csource() {return move_only();} |
| 30 | |
| 31 | void test(move_only) {} |
| 32 | |
| 33 | int x = 42; |
| 34 | const int& cx = x; |
| 35 | |
| 36 | template <class QualInt> |
| 37 | QualInt get() TEST_NOEXCEPT { return static_cast<QualInt>(x); } |
| 38 | |
| 39 | |
| 40 | int copy_ctor = 0; |
| 41 | int move_ctor = 0; |
| 42 | |
| 43 | struct A { |
| 44 | A() {} |
| 45 | A(const A&) {++copy_ctor;} |
| 46 | A(A&&) {++move_ctor;} |
| 47 | A& operator=(const A&) = delete; |
| 48 | }; |
| 49 | |
| 50 | #if TEST_STD_VER > 11 |
| 51 | constexpr bool test_constexpr_move() { |
| 52 | int y = 42; |
| 53 | const int cy = y; |
| 54 | return std::move(y) == 42 |
| 55 | && std::move(cy) == 42 |
| 56 | && std::move(static_cast<int&&>(y)) == 42 |
| 57 | && std::move(static_cast<int const&&>(y)) == 42; |
| 58 | } |
| 59 | #endif |
| 60 | int main(int, char**) |
| 61 | { |
| 62 | { // Test return type and noexcept. |
| 63 | static_assert(std::is_same<decltype(std::move(x)), int&&>::value, "" ); |
| 64 | ASSERT_NOEXCEPT(std::move(x)); |
| 65 | static_assert(std::is_same<decltype(std::move(cx)), const int&&>::value, "" ); |
| 66 | ASSERT_NOEXCEPT(std::move(cx)); |
| 67 | static_assert(std::is_same<decltype(std::move(42)), int&&>::value, "" ); |
| 68 | ASSERT_NOEXCEPT(std::move(42)); |
| 69 | static_assert(std::is_same<decltype(std::move(get<const int&&>())), const int&&>::value, "" ); |
| 70 | ASSERT_NOEXCEPT(std::move(get<int const&&>())); |
| 71 | } |
| 72 | { // test copy and move semantics |
| 73 | A a; |
| 74 | const A ca = A(); |
| 75 | |
| 76 | assert(copy_ctor == 0); |
| 77 | assert(move_ctor == 0); |
| 78 | |
| 79 | A a2 = a; (void)a2; |
| 80 | assert(copy_ctor == 1); |
| 81 | assert(move_ctor == 0); |
| 82 | |
| 83 | A a3 = std::move(a); (void)a3; |
| 84 | assert(copy_ctor == 1); |
| 85 | assert(move_ctor == 1); |
| 86 | |
| 87 | A a4 = ca; (void)a4; |
| 88 | assert(copy_ctor == 2); |
| 89 | assert(move_ctor == 1); |
| 90 | |
| 91 | A a5 = std::move(ca); (void)a5; |
| 92 | assert(copy_ctor == 3); |
| 93 | assert(move_ctor == 1); |
| 94 | } |
| 95 | { // test on a move only type |
| 96 | move_only mo; |
| 97 | test(std::move(mo)); |
| 98 | test(source()); |
| 99 | } |
| 100 | #if TEST_STD_VER > 11 |
| 101 | { |
| 102 | constexpr int y = 42; |
| 103 | static_assert(std::move(y) == 42, "" ); |
| 104 | static_assert(test_constexpr_move(), "" ); |
| 105 | } |
| 106 | #endif |
| 107 | #if TEST_STD_VER == 11 && defined(_LIBCPP_VERSION) |
| 108 | // Test that std::forward is constexpr in C++11. This is an extension |
| 109 | // provided by both libc++ and libstdc++. |
| 110 | { |
| 111 | constexpr int y = 42; |
| 112 | static_assert(std::move(y) == 42, "" ); |
| 113 | } |
| 114 | #endif |
| 115 | |
| 116 | return 0; |
| 117 | } |
| 118 | |