libcxx/test/std/iterators/predef.iterators/counted.iterator/plus.pass.cpp

   1 //===----------------------------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 // UNSUPPORTED: c++03, c++11, c++14, c++17
  10
  11 // constexpr counted_iterator operator+(iter_difference_t<I> n) const
  12 //     requires random_access_iterator<I>;
  13 // friend constexpr counted_iterator operator+(
  14 //   iter_difference_t<I> n, const counted_iterator& x)
  15 //     requires random_access_iterator<I>;
  16 // constexpr counted_iterator& operator+=(iter_difference_t<I> n)
  17 //     requires random_access_iterator<I>;
  18
  19 #include <iterator>
  20
  21 #include "test_macros.h"
  22 #include "test_iterators.h"
  23
  24 template<class Iter>
  25 concept PlusEnabled = requires(Iter& iter) {
  26   iter + 1;
  27 };
  28
  29 template<class Iter>
  30 concept PlusEqEnabled = requires(Iter& iter) {
  31   iter += 1;
  32 };
  33
  34 constexpr bool test() {
  35   int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8};
  36
  37   {
  38     {
  39       using Counted = std::counted_iterator<random_access_iterator<int*>>;
  40       std::counted_iterator iter(random_access_iterator<int*>{buffer}, 8);
  41       assert(iter + 2 == Counted(random_access_iterator<int*>{buffer + 2}, 6));
  42       assert(iter + 0 == Counted(random_access_iterator<int*>{buffer}, 8));
  43
  44       ASSERT_SAME_TYPE(decltype(iter + 2), Counted);
  45     }
  46     {
  47       using Counted = const std::counted_iterator<random_access_iterator<int*>>;
  48       const std::counted_iterator iter(random_access_iterator<int*>{buffer}, 8);
  49       assert(iter + 8 == Counted(random_access_iterator<int*>{buffer + 8}, 0));
  50       assert(iter + 0 == Counted(random_access_iterator<int*>{buffer}, 8));
  51
  52       ASSERT_SAME_TYPE(decltype(iter + 2), std::remove_const_t<Counted>);
  53     }
  54   }
  55
  56   {
  57     {
  58       using Counted = std::counted_iterator<random_access_iterator<int*>>;
  59       std::counted_iterator iter(random_access_iterator<int*>{buffer}, 8);
  60       assert(2 + iter == Counted(random_access_iterator<int*>{buffer + 2}, 6));
  61       assert(0 + iter == Counted(random_access_iterator<int*>{buffer}, 8));
  62
  63       ASSERT_SAME_TYPE(decltype(iter + 2), Counted);
  64     }
  65     {
  66       using Counted = const std::counted_iterator<random_access_iterator<int*>>;
  67       const std::counted_iterator iter(random_access_iterator<int*>{buffer}, 8);
  68       assert(8 + iter == Counted(random_access_iterator<int*>{buffer + 8}, 0));
  69       assert(0 + iter == Counted(random_access_iterator<int*>{buffer}, 8));
  70
  71       ASSERT_SAME_TYPE(decltype(iter + 2), std::remove_const_t<Counted>);
  72     }
  73   }
  74
  75   {
  76     {
  77       using Counted = std::counted_iterator<random_access_iterator<int*>>;
  78       std::counted_iterator iter(random_access_iterator<int*>{buffer}, 8);
  79       assert((iter += 2) == Counted(random_access_iterator<int*>{buffer + 2}, 6));
  80       assert((iter += 0) == Counted(random_access_iterator<int*>{buffer + 2}, 6));
  81
  82       ASSERT_SAME_TYPE(decltype(iter += 2), Counted&);
  83     }
  84     {
  85       using Counted = std::counted_iterator<contiguous_iterator<int*>>;
  86       std::counted_iterator iter(contiguous_iterator<int*>{buffer}, 8);
  87       assert((iter += 8) == Counted(contiguous_iterator<int*>{buffer + 8}, 0));
  88       assert((iter += 0) == Counted(contiguous_iterator<int*>{buffer + 8}, 0));
  89
  90       ASSERT_SAME_TYPE(decltype(iter += 2), Counted&);
  91     }
  92     {
  93       static_assert( PlusEnabled<std::counted_iterator<random_access_iterator<int*>>>);
  94       static_assert(!PlusEnabled<std::counted_iterator<bidirectional_iterator<int*>>>);
  95
  96       static_assert( PlusEqEnabled<      std::counted_iterator<random_access_iterator<int*>>>);
  97       static_assert(!PlusEqEnabled<const std::counted_iterator<random_access_iterator<int*>>>);
  98     }
  99   }
 100
 101   return true;
 102 }
 103
 104 int main(int, char**) {
 105   test();
 106   static_assert(test());
 107
 108   return 0;
 109 }