1//===----------------------------------------------------------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is dual licensed under the MIT and the University of Illinois Open
6// Source Licenses. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9
10// UNSUPPORTED: c++98, c++03, c++11, c++14
11// <optional>
12
13
14#include <optional>
15#include <type_traits>
16#include <cassert>
17
18#include "archetypes.hpp"
19
20template <class T>
21struct SpecialMemberTest {
22    using O = std::optional<T>;
23
24    static_assert(std::is_default_constructible_v<O>,
25        "optional is always default constructible.");
26    static_assert(std::is_copy_constructible_v<O> == std::is_copy_constructible_v<T>,
27        "optional<T> is copy constructible if and only if T is copy constructible.");
28    static_assert(std::is_move_constructible_v<O> ==
29        (std::is_copy_constructible_v<T> || std::is_move_constructible_v<T>),
30        "optional<T> is move constructible if and only if T is copy or move constructible.");
31    static_assert(std::is_copy_assignable_v<O> ==
32        (std::is_copy_constructible_v<T> && std::is_copy_assignable_v<T>),
33        "optional<T> is copy assignable if and only if T is both copy "
34        "constructible and copy assignable.");
35    static_assert(std::is_move_assignable_v<O> ==
36        ((std::is_copy_constructible_v<T> && std::is_copy_assignable_v<T>) ||
37         (std::is_move_constructible_v<T> && std::is_move_assignable_v<T>)),
38        "optional<T> is move assignable if and only if T is both move assignable and "
39        "move constructible, or both copy constructible and copy assignable.");
40};
41
42template <class ...Args> static void sink(Args&&...) {}
43
44template <class ...TestTypes>
45struct DoTestsMetafunction {
46    DoTestsMetafunction() { sink(SpecialMemberTest<TestTypes>{}...); }
47};
48
49struct TrivialMoveNonTrivialCopy {
50    TrivialMoveNonTrivialCopy() = default;
51    TrivialMoveNonTrivialCopy(const TrivialMoveNonTrivialCopy&) {}
52    TrivialMoveNonTrivialCopy(TrivialMoveNonTrivialCopy&&) = default;
53    TrivialMoveNonTrivialCopy& operator=(const TrivialMoveNonTrivialCopy&) { return *this; }
54    TrivialMoveNonTrivialCopy& operator=(TrivialMoveNonTrivialCopy&&) = default;
55};
56
57struct TrivialCopyNonTrivialMove {
58    TrivialCopyNonTrivialMove() = default;
59    TrivialCopyNonTrivialMove(const TrivialCopyNonTrivialMove&) = default;
60    TrivialCopyNonTrivialMove(TrivialCopyNonTrivialMove&&) {}
61    TrivialCopyNonTrivialMove& operator=(const TrivialCopyNonTrivialMove&) = default;
62    TrivialCopyNonTrivialMove& operator=(TrivialCopyNonTrivialMove&&) { return *this; }
63};
64
65int main()
66{
67    sink(
68        ImplicitTypes::ApplyTypes<DoTestsMetafunction>{},
69        ExplicitTypes::ApplyTypes<DoTestsMetafunction>{},
70        NonLiteralTypes::ApplyTypes<DoTestsMetafunction>{},
71        NonTrivialTypes::ApplyTypes<DoTestsMetafunction>{},
72        DoTestsMetafunction<TrivialMoveNonTrivialCopy, TrivialCopyNonTrivialMove>{}
73    );
74}
75