xref: /llvm-project/libcxx/test/std/iterators/predef.iterators/counted.iterator/plus.pass.cpp (revision d2baefae6846765eef6a6dd69d4fdf1082ce29ad)
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 
test()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 
main(int,char **)104 int main(int, char**) {
105   test();
106   static_assert(test());
107 
108   return 0;
109 }
110