You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
This repo is archived. You can view files and clone it, but cannot push or open issues/pull-requests.
libcxx_old/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/default.pass.cpp

113 lines
3.0 KiB
C++

//===----------------------------------------------------------------------===//
//
// 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;
// constexpr tuple();
// UNSUPPORTED: c++98, c++03
#include <tuple>
#include <string>
#include <cassert>
#include <type_traits>
#include "test_macros.h"
#include "DefaultOnly.h"
struct NoDefault {
NoDefault() = delete;
explicit NoDefault(int) { }
};
struct NoExceptDefault {
NoExceptDefault() noexcept = default;
};
struct ThrowingDefault {
ThrowingDefault() { }
};
struct IllFormedDefault {
IllFormedDefault(int x) : value(x) {}
template <bool Pred = false>
constexpr IllFormedDefault() {
static_assert(Pred,
"The default constructor should not be instantiated");
}
int value;
};
int main(int, char**)
{
{
std::tuple<> t;
(void)t;
}
{
std::tuple<int> t;
assert(std::get<0>(t) == 0);
}
{
std::tuple<int, char*> t;
assert(std::get<0>(t) == 0);
assert(std::get<1>(t) == nullptr);
}
{
std::tuple<int, char*, std::string> t;
assert(std::get<0>(t) == 0);
assert(std::get<1>(t) == nullptr);
assert(std::get<2>(t) == "");
}
{
std::tuple<int, char*, std::string, DefaultOnly> t;
assert(std::get<0>(t) == 0);
assert(std::get<1>(t) == nullptr);
assert(std::get<2>(t) == "");
assert(std::get<3>(t) == DefaultOnly());
}
{
// See bug #21157.
static_assert(!std::is_default_constructible<std::tuple<NoDefault>>(), "");
static_assert(!std::is_default_constructible<std::tuple<DefaultOnly, NoDefault>>(), "");
static_assert(!std::is_default_constructible<std::tuple<NoDefault, DefaultOnly, NoDefault>>(), "");
}
{
static_assert(noexcept(std::tuple<NoExceptDefault>()), "");
static_assert(noexcept(std::tuple<NoExceptDefault, NoExceptDefault>()), "");
static_assert(!noexcept(std::tuple<ThrowingDefault, NoExceptDefault>()), "");
static_assert(!noexcept(std::tuple<NoExceptDefault, ThrowingDefault>()), "");
static_assert(!noexcept(std::tuple<ThrowingDefault, ThrowingDefault>()), "");
}
{
constexpr std::tuple<> t;
(void)t;
}
{
constexpr std::tuple<int> t;
assert(std::get<0>(t) == 0);
}
{
constexpr std::tuple<int, char*> t;
assert(std::get<0>(t) == 0);
assert(std::get<1>(t) == nullptr);
}
{
// Check that the SFINAE on the default constructor is not evaluated when
// it isn't needed. If the default constructor is evaluated then this test
// should fail to compile.
IllFormedDefault v(0);
std::tuple<IllFormedDefault> t(v);
}
return 0;
}