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//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// <tuple>
// template <class... Types> class tuple;
// template <class... UTypes>
// explicit tuple(UTypes&&... u);
// UNSUPPORTED: c++98, c++03
#include <tuple>
#include <cassert>
#include <type_traits>
#include "test_macros.h"
#include "test_convertible.hpp"
#include "MoveOnly.h"
#if TEST_STD_VER > 11
struct Empty {};
struct A
{
int id_;
explicit constexpr A(int i) : id_(i) {}
};
#endif
struct NoDefault { NoDefault() = delete; };
// Make sure the _Up... constructor SFINAEs out when the types that
// are not explicitly initialized are not all default constructible.
// Otherwise, std::is_constructible would return true but instantiating
// the constructor would fail.
void test_default_constructible_extension_sfinae()
{
{
typedef std::tuple<MoveOnly, NoDefault> Tuple;
static_assert(!std::is_constructible<
Tuple,
MoveOnly
>::value, "");
static_assert(std::is_constructible<
Tuple,
MoveOnly, NoDefault
>::value, "");
}
{
typedef std::tuple<MoveOnly, MoveOnly, NoDefault> Tuple;
static_assert(!std::is_constructible<
Tuple,
MoveOnly, MoveOnly
>::value, "");
static_assert(std::is_constructible<
Tuple,
MoveOnly, MoveOnly, NoDefault
>::value, "");
}
{
// Same idea as above but with a nested tuple type.
typedef std::tuple<MoveOnly, NoDefault> Tuple;
typedef std::tuple<MoveOnly, Tuple, MoveOnly, MoveOnly> NestedTuple;
static_assert(!std::is_constructible<
NestedTuple,
MoveOnly, MoveOnly, MoveOnly, MoveOnly
>::value, "");
static_assert(std::is_constructible<
NestedTuple,
MoveOnly, Tuple, MoveOnly, MoveOnly
>::value, "");
}
// testing extensions
#ifdef _LIBCPP_VERSION
{
typedef std::tuple<MoveOnly, int> Tuple;
typedef std::tuple<MoveOnly, Tuple, MoveOnly, MoveOnly> NestedTuple;
static_assert(std::is_constructible<
NestedTuple,
MoveOnly, MoveOnly, MoveOnly, MoveOnly
>::value, "");
static_assert(std::is_constructible<
NestedTuple,
MoveOnly, Tuple, MoveOnly, MoveOnly
>::value, "");
}
#endif
}
int main(int, char**)
{
{
std::tuple<MoveOnly> t(MoveOnly(0));
assert(std::get<0>(t) == 0);
}
{
std::tuple<MoveOnly, MoveOnly> t(MoveOnly(0), MoveOnly(1));
assert(std::get<0>(t) == 0);
assert(std::get<1>(t) == 1);
}
{
std::tuple<MoveOnly, MoveOnly, MoveOnly> t(MoveOnly(0),
MoveOnly(1),
MoveOnly(2));
assert(std::get<0>(t) == 0);
assert(std::get<1>(t) == 1);
assert(std::get<2>(t) == 2);
}
// extensions
#ifdef _LIBCPP_VERSION
{
using E = MoveOnly;
using Tup = std::tuple<E, E, E>;
// Test that the reduced arity initialization extension is only
// allowed on the explicit constructor.
static_assert(test_convertible<Tup, E, E, E>(), "");
Tup t(E(0), E(1));
static_assert(!test_convertible<Tup, E, E>(), "");
assert(std::get<0>(t) == 0);
assert(std::get<1>(t) == 1);
assert(std::get<2>(t) == MoveOnly());
Tup t2(E(0));
static_assert(!test_convertible<Tup, E>(), "");
assert(std::get<0>(t) == 0);
assert(std::get<1>(t) == E());
assert(std::get<2>(t) == E());
}
#endif
#if TEST_STD_VER > 11
{
constexpr std::tuple<Empty> t0{Empty()};
(void)t0;
}
{
constexpr std::tuple<A, A> t(3, 2);
static_assert(std::get<0>(t).id_ == 3, "");
}
#endif
// Check that SFINAE is properly applied with the default reduced arity
// constructor extensions.
test_default_constructible_extension_sfinae();
return 0;
}
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