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
10
11// constexpr expected(expected&& rhs) noexcept(is_nothrow_move_constructible_v<E>);
12//
13// Constraints: is_move_constructible_v<E> is true.
14//
15// Effects: If rhs.has_value() is false, direct-non-list-initializes unex with std::move(rhs.error()).
16//
17// Postconditions: rhs.has_value() is unchanged; rhs.has_value() == this->has_value() is true.
18//
19// Throws: Any exception thrown by the initialization of unex.
20//
21// Remarks: This constructor is trivial if is_trivially_move_constructible_v<E> is true.
22
23#include <cassert>
24#include <expected>
25#include <type_traits>
26#include <utility>
27
28#include "test_macros.h"
29#include "../../types.h"
30
31struct NonMovable {
32 NonMovable(NonMovable&&) = delete;
33};
34
35struct MovableNonTrivial {
36 int i;
37 constexpr MovableNonTrivial(int ii) : i(ii) {}
38 constexpr MovableNonTrivial(MovableNonTrivial&& o) : i(o.i) { o.i = 0; }
39 friend constexpr bool operator==(const MovableNonTrivial&, const MovableNonTrivial&) = default;
40};
41
42struct MoveMayThrow {
43 MoveMayThrow(MoveMayThrow&&) {}
44};
45
46// Test Constraints:
47// - is_move_constructible_v<E> is true.
48static_assert(std::is_move_constructible_v<std::expected<void, int>>);
49static_assert(std::is_move_constructible_v<std::expected<void, MovableNonTrivial>>);
50static_assert(!std::is_move_constructible_v<std::expected<void, NonMovable>>);
51
52// Test: This constructor is trivial if is_trivially_move_constructible_v<E> is true.
53static_assert(std::is_trivially_move_constructible_v<std::expected<void, int>>);
54static_assert(!std::is_trivially_move_constructible_v<std::expected<void, MovableNonTrivial>>);
55
56// Test: noexcept(is_nothrow_move_constructible_v<E>)
57static_assert(std::is_nothrow_move_constructible_v<std::expected<int, int>>);
58static_assert(!std::is_nothrow_move_constructible_v<std::expected<MoveMayThrow, int>>);
59static_assert(!std::is_nothrow_move_constructible_v<std::expected<int, MoveMayThrow>>);
60static_assert(!std::is_nothrow_move_constructible_v<std::expected<MoveMayThrow, MoveMayThrow>>);
61
62constexpr bool test() {
63 // move the error non-trivial
64 {
65 std::expected<void, MovableNonTrivial> e1(std::unexpect, 5);
66 auto e2 = std::move(e1);
67 assert(!e2.has_value());
68 assert(e2.error().i == 5);
69 assert(!e1.has_value());
70 assert(e1.error().i == 0);
71 }
72
73 // move the error trivial
74 {
75 std::expected<void, int> e1(std::unexpect, 5);
76 auto e2 = std::move(e1);
77 assert(!e2.has_value());
78 assert(e2.error() == 5);
79 assert(!e1.has_value());
80 }
81
82 // move TailClobbererNonTrivialMove as error
83 {
84 std::expected<void, TailClobbererNonTrivialMove<1>> e1(std::unexpect);
85 auto e2 = std::move(e1);
86 assert(!e2.has_value());
87 assert(!e1.has_value());
88 }
89
90 return true;
91}
92
93void testException() {
94#ifndef TEST_HAS_NO_EXCEPTIONS
95 struct Throwing {
96 Throwing() = default;
97 Throwing(Throwing&&) { throw Except{}; }
98 };
99
100 // throw on moving error
101 {
102 std::expected<void, Throwing> e1(std::unexpect);
103 try {
104 [[maybe_unused]] auto e2 = std::move(e1);
105 assert(false);
106 } catch (Except) {
107 }
108 }
109
110#endif // TEST_HAS_NO_EXCEPTIONS
111}
112
113int main(int, char**) {
114 test();
115 static_assert(test());
116 testException();
117 return 0;
118}
119

source code of libcxx/test/std/utilities/expected/expected.void/ctor/ctor.move.pass.cpp