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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 const&);
#include <cassert>
#include <type_traits>
#include <variant>
#include "test_macros.h"
struct NonT {
NonT(int v) : value(v) {}
NonT(NonT const &o) : value(o.value) {}
int value;
};
static_assert(!std::is_trivially_copy_constructible<NonT>::value, "");
struct NoCopy {
NoCopy(NoCopy const &) = delete;
};
struct MoveOnly {
MoveOnly(MoveOnly const &) = delete;
MoveOnly(MoveOnly &&) = default;
};
struct MoveOnlyNT {
MoveOnlyNT(MoveOnlyNT const &) = delete;
MoveOnlyNT(MoveOnlyNT &&) {}
};
#ifndef TEST_HAS_NO_EXCEPTIONS
struct MakeEmptyT {
static int alive;
MakeEmptyT() { ++alive; }
MakeEmptyT(MakeEmptyT const &) {
++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=(MakeEmptyT const &) { 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_copy_ctor_sfinae() {
{
using V = std::variant<int, long>;
static_assert(std::is_copy_constructible<V>::value, "");
}
{
using V = std::variant<int, NoCopy>;
static_assert(!std::is_copy_constructible<V>::value, "");
}
{
using V = std::variant<int, MoveOnly>;
static_assert(!std::is_copy_constructible<V>::value, "");
}
{
using V = std::variant<int, MoveOnlyNT>;
static_assert(!std::is_copy_constructible<V>::value, "");
}
}
void test_copy_ctor_basic() {
{
std::variant<int> v(std::in_place_index<0>, 42);
std::variant<int> v2 = 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 = v;
assert(v2.index() == 1);
assert(std::get<1>(v2) == 42);
}
{
std::variant<NonT> v(std::in_place_index<0>, 42);
assert(v.index() == 0);
std::variant<NonT> v2(v);
assert(v2.index() == 0);
assert(std::get<0>(v2).value == 42);
}
{
std::variant<int, NonT> v(std::in_place_index<1>, 42);
assert(v.index() == 1);
std::variant<int, NonT> v2(v);
assert(v2.index() == 1);
assert(std::get<1>(v2).value == 42);
}
}
void test_copy_ctor_valueless_by_exception() {
#ifndef TEST_HAS_NO_EXCEPTIONS
using V = std::variant<int, MakeEmptyT>;
V v1;
makeEmpty(v1);
V const &cv1 = v1;
V v(cv1);
assert(v.valueless_by_exception());
#endif
}
int main() {
test_copy_ctor_basic();
test_copy_ctor_valueless_by_exception();
test_copy_ctor_sfinae();
}
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