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// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++98, c++03, c++11, c++14
// <variant>
// template <class ...Types> class variant;
// variant(variant&&) noexcept(see below);
#include <cassert>
#include <string>
#include <type_traits>
#include <variant>
#include "test_macros.h"
#include "test_workarounds.h"
struct ThrowsMove {
ThrowsMove(ThrowsMove &&) noexcept(false) {}
};
struct NoCopy {
NoCopy(const NoCopy &) = delete;
};
struct MoveOnly {
int value;
MoveOnly(int v) : value(v) {}
MoveOnly(const MoveOnly &) = delete;
MoveOnly(MoveOnly &&) = default;
};
struct MoveOnlyNT {
int value;
MoveOnlyNT(int v) : value(v) {}
MoveOnlyNT(const MoveOnlyNT &) = delete;
MoveOnlyNT(MoveOnlyNT &&other) : value(other.value) { other.value = -1; }
};
#ifndef TEST_HAS_NO_EXCEPTIONS
struct MakeEmptyT {
static int alive;
MakeEmptyT() { ++alive; }
MakeEmptyT(const MakeEmptyT &) {
++alive;
// Don't throw from the copy constructor since variant's assignment
// operator performs a copy before committing to the assignment.
}
MakeEmptyT(MakeEmptyT &&) { throw 42; }
MakeEmptyT &operator=(const MakeEmptyT &) { throw 42; }
MakeEmptyT &operator=(MakeEmptyT &&) { throw 42; }
~MakeEmptyT() { --alive; }
};
int MakeEmptyT::alive = 0;
template <class Variant> void makeEmpty(Variant &v) {
Variant v2(std::in_place_type<MakeEmptyT>);
try {
v = v2;
assert(false);
} catch (...) {
assert(v.valueless_by_exception());
}
}
#endif // TEST_HAS_NO_EXCEPTIONS
void test_move_noexcept() {
{
using V = std::variant<int, long>;
static_assert(std::is_nothrow_move_constructible<V>::value, "");
}
{
using V = std::variant<int, MoveOnly>;
static_assert(std::is_nothrow_move_constructible<V>::value, "");
}
{
using V = std::variant<int, MoveOnlyNT>;
static_assert(!std::is_nothrow_move_constructible<V>::value, "");
}
{
using V = std::variant<int, ThrowsMove>;
static_assert(!std::is_nothrow_move_constructible<V>::value, "");
}
}
void test_move_ctor_sfinae() {
{
using V = std::variant<int, long>;
static_assert(std::is_move_constructible<V>::value, "");
}
{
using V = std::variant<int, MoveOnly>;
static_assert(std::is_move_constructible<V>::value, "");
}
{
using V = std::variant<int, MoveOnlyNT>;
static_assert(std::is_move_constructible<V>::value, "");
}
{
using V = std::variant<int, NoCopy>;
static_assert(!std::is_move_constructible<V>::value, "");
}
}
void test_move_ctor_basic() {
{
std::variant<int> v(std::in_place_index<0>, 42);
std::variant<int> v2 = std::move(v);
assert(v2.index() == 0);
assert(std::get<0>(v2) == 42);
}
{
std::variant<int, long> v(std::in_place_index<1>, 42);
std::variant<int, long> v2 = std::move(v);
assert(v2.index() == 1);
assert(std::get<1>(v2) == 42);
}
{
std::variant<MoveOnly> v(std::in_place_index<0>, 42);
assert(v.index() == 0);
std::variant<MoveOnly> v2(std::move(v));
assert(v2.index() == 0);
assert(std::get<0>(v2).value == 42);
}
{
std::variant<int, MoveOnly> v(std::in_place_index<1>, 42);
assert(v.index() == 1);
std::variant<int, MoveOnly> v2(std::move(v));
assert(v2.index() == 1);
assert(std::get<1>(v2).value == 42);
}
{
std::variant<MoveOnlyNT> v(std::in_place_index<0>, 42);
assert(v.index() == 0);
std::variant<MoveOnlyNT> v2(std::move(v));
assert(v2.index() == 0);
assert(std::get<0>(v).value == -1);
assert(std::get<0>(v2).value == 42);
}
{
std::variant<int, MoveOnlyNT> v(std::in_place_index<1>, 42);
assert(v.index() == 1);
std::variant<int, MoveOnlyNT> v2(std::move(v));
assert(v2.index() == 1);
assert(std::get<1>(v).value == -1);
assert(std::get<1>(v2).value == 42);
}
}
void test_move_ctor_valueless_by_exception() {
#ifndef TEST_HAS_NO_EXCEPTIONS
using V = std::variant<int, MakeEmptyT>;
V v1;
makeEmpty(v1);
V v(std::move(v1));
assert(v.valueless_by_exception());
#endif
}
template <size_t Idx>
constexpr bool test_constexpr_ctor_extension_imp(
std::variant<long, void*, const int> const& v)
{
auto copy = v;
auto v2 = std::move(copy);
return v2.index() == v.index() &&
v2.index() == Idx &&
std::get<Idx>(v2) == std::get<Idx>(v);
}
void test_constexpr_move_ctor_extension() {
#if defined(_LIBCPP_VER) || defined(_MSVC_STL_VER)
using V = std::variant<long, void*, const int>;
#ifdef TEST_WORKAROUND_C1XX_BROKEN_IS_TRIVIALLY_COPYABLE
static_assert(std::is_trivially_destructible<V>::value, "");
static_assert(std::is_trivially_copy_constructible<V>::value, "");
static_assert(std::is_trivially_move_constructible<V>::value, "");
static_assert(!std::is_copy_assignable<V>::value, "");
static_assert(!std::is_move_assignable<V>::value, "");
#else
static_assert(std::is_trivially_copyable<V>::value, "");
#endif
static_assert(std::is_trivially_move_constructible<V>::value, "");
static_assert(test_constexpr_ctor_extension_imp<0>(V(42l)), "");
static_assert(test_constexpr_ctor_extension_imp<1>(V(nullptr)), "");
static_assert(test_constexpr_ctor_extension_imp<2>(V(101)), "");
#endif
}
int main() {
test_move_ctor_basic();
test_move_ctor_valueless_by_exception();
test_move_noexcept();
test_move_ctor_sfinae();
test_constexpr_move_ctor_extension();
}
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