//===----------------------------------------------------------------------===//
//
// 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
// SPDX-FileCopyrightText: Copyright (c) 2023 NVIDIA CORPORATION & AFFILIATES.
//
//===----------------------------------------------------------------------===//

// <cuda/std/iterator>

// move_iterator

// template <RandomAccessIterator Iter1, RandomAccessIterator Iter2>
//   requires HasMinus<Iter1, Iter2>
//   auto
//   operator-(const move_iterator<Iter1>& x, const move_iterator<Iter2>& y)
//   -> decltype(x.base() - y.base());
//
//  constexpr in C++17

#include <cuda/std/cassert>
#include <cuda/std/iterator>

#include "test_iterators.h"
#include "test_macros.h"

template <class It>
__host__ __device__ void test(It l, It r, typename cuda::std::iterator_traits<It>::difference_type x)
{
  const cuda::std::move_iterator<It> r1(l);
  const cuda::std::move_iterator<It> r2(r);
  assert(r1 - r2 == x);
}

int main(int, char**)
{
  char s[] = "1234567890";
  test(random_access_iterator<char*>(s + 5), random_access_iterator<char*>(s), 5);
  test(s + 5, s, 5);

  {
    constexpr const char* p = "123456789";
    typedef cuda::std::move_iterator<const char*> MI;
    constexpr MI it1 = cuda::std::make_move_iterator(p);
    constexpr MI it2 = cuda::std::make_move_iterator(p + 1);
    static_assert(it1 - it2 == -1, "");
    static_assert(it2 - it1 == 1, "");
  }

  return 0;
}
