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 // template<input_iterator I>
12 //   requires same_as<ITER_TRAITS(I), iterator_traits<I>>   // see [iterator.concepts.general]
13 // struct iterator_traits<counted_iterator<I>> : iterator_traits<I> {
14 //   using pointer = conditional_t<contiguous_iterator<I>,
15 //                                 add_pointer_t<iter_reference_t<I>>, void>;
16 // };
17 
18 #include <iterator>
19 
20 #include "test_macros.h"
21 #include "test_iterators.h"
22 
test()23 void test() {
24   {
25     using Iter = cpp17_input_iterator<int*>;
26     using CommonIter = std::counted_iterator<Iter>;
27     using IterTraits = std::iterator_traits<CommonIter>;
28 
29     static_assert(std::same_as<IterTraits::iterator_category, std::input_iterator_tag>);
30     static_assert(std::same_as<IterTraits::value_type, int>);
31     static_assert(std::same_as<IterTraits::difference_type, std::ptrdiff_t>);
32     static_assert(std::same_as<IterTraits::pointer, void>);
33     static_assert(std::same_as<IterTraits::reference, int&>);
34   }
35   {
36     using Iter = forward_iterator<int*>;
37     using CommonIter = std::counted_iterator<Iter>;
38     using IterTraits = std::iterator_traits<CommonIter>;
39 
40     static_assert(std::same_as<IterTraits::iterator_category, std::forward_iterator_tag>);
41     static_assert(std::same_as<IterTraits::value_type, int>);
42     static_assert(std::same_as<IterTraits::difference_type, std::ptrdiff_t>);
43     static_assert(std::same_as<IterTraits::pointer, void>);
44     static_assert(std::same_as<IterTraits::reference, int&>);
45   }
46   {
47     using Iter = random_access_iterator<int*>;
48     using CommonIter = std::counted_iterator<Iter>;
49     using IterTraits = std::iterator_traits<CommonIter>;
50 
51     static_assert(std::same_as<IterTraits::iterator_category, std::random_access_iterator_tag>);
52     static_assert(std::same_as<IterTraits::value_type, int>);
53     static_assert(std::same_as<IterTraits::difference_type, std::ptrdiff_t>);
54     static_assert(std::same_as<IterTraits::pointer, void>);
55     static_assert(std::same_as<IterTraits::reference, int&>);
56   }
57   {
58     using Iter = contiguous_iterator<int*>;
59     using CommonIter = std::counted_iterator<Iter>;
60     using IterTraits = std::iterator_traits<CommonIter>;
61 
62     static_assert(std::same_as<IterTraits::iterator_category, std::contiguous_iterator_tag>);
63     static_assert(std::same_as<IterTraits::value_type, int>);
64     static_assert(std::same_as<IterTraits::difference_type, std::ptrdiff_t>);
65     static_assert(std::same_as<IterTraits::pointer, int*>);
66     static_assert(std::same_as<IterTraits::reference, int&>);
67   }
68 }
69