llvm/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_convert_copy.pass.cpp

//===----------------------------------------------------------------------===//
//
// 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 Alloc, class... UTypes>
// constexpr                                        // since c++20
//   tuple(allocator_arg_t, const Alloc& a, const tuple<UTypes...>&);

// UNSUPPORTED: c++03

#include <tuple>
#include <memory>
#include <cassert>

#include "test_macros.h"
#include "allocators.h"
#include "test_allocator.h"
#include "../alloc_first.h"
#include "../alloc_last.h"

struct Explicit {
  int value;
  explicit Explicit(int x) : value(x) {}
};

struct Implicit {
  int value;
  Implicit(int x) : value(x) {}
};

#if TEST_STD_VER > 17
constexpr bool alloc_copy_constructor_is_constexpr() {
  const std::tuple<int> t1 = 1;
  std::tuple<int> t2 = {std::allocator_arg, test_allocator<int>{}, t1};
  assert(std::get<0>(t2) == 1);
  return true;
}
#endif

int main(int, char**)
{
    {
        typedef std::tuple<long> T0;
        typedef std::tuple<long long> T1;
        T0 t0(2);
        T1 t1(std::allocator_arg, A1<int>(), t0);
        assert(std::get<0>(t1) == 2);
    }
    {
        typedef std::tuple<int> T0;
        typedef std::tuple<alloc_first> T1;
        T0 t0(2);
        alloc_first::allocator_constructed = false;
        T1 t1(std::allocator_arg, A1<int>(5), t0);
        assert(alloc_first::allocator_constructed);
        assert(std::get<0>(t1) == 2);
    }
    {
        typedef std::tuple<int, int> T0;
        typedef std::tuple<alloc_first, alloc_last> T1;
        T0 t0(2, 3);
        alloc_first::allocator_constructed = false;
        alloc_last::allocator_constructed = false;
        T1 t1(std::allocator_arg, A1<int>(5), t0);
        assert(alloc_first::allocator_constructed);
        assert(alloc_last::allocator_constructed);
        assert(std::get<0>(t1) == 2);
        assert(std::get<1>(t1) == 3);
    }
    {
        typedef std::tuple<long, int, int> T0;
        typedef std::tuple<long long, alloc_first, alloc_last> T1;
        T0 t0(1, 2, 3);
        alloc_first::allocator_constructed = false;
        alloc_last::allocator_constructed = false;
        T1 t1(std::allocator_arg, A1<int>(5), t0);
        assert(alloc_first::allocator_constructed);
        assert(alloc_last::allocator_constructed);
        assert(std::get<0>(t1) == 1);
        assert(std::get<1>(t1) == 2);
        assert(std::get<2>(t1) == 3);
    }
    {
        const std::tuple<int> t1(42);
        std::tuple<Explicit> t2{std::allocator_arg, std::allocator<int>{},  t1};
        assert(std::get<0>(t2).value == 42);
    }
    {
        const std::tuple<int> t1(42);
        std::tuple<Implicit> t2 = {std::allocator_arg, std::allocator<int>{}, t1};
        assert(std::get<0>(t2).value == 42);
    }
    {
        // Test that we can use a tag derived from allocator_arg_t
        struct DerivedFromAllocatorArgT : std::allocator_arg_t { };
        DerivedFromAllocatorArgT derived;
        std::tuple<long> from(3l);
        std::tuple<long long> t0(derived, A1<int>(), from);
    }

#if TEST_STD_VER > 17
    static_assert(alloc_copy_constructor_is_constexpr());
#endif
    return 0;
}