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 // UNSUPPORTED: libcpp-no-concepts
11 // UNSUPPORTED: gcc-10
12 
13 // template<sized_sentinel_for<I> I2, sized_sentinel_for<I> S2>
14 //   requires sized_sentinel_for<S, I2>
15 // friend iter_difference_t<I2> operator-(
16 //   const common_iterator& x, const common_iterator<I2, S2>& y);
17 
18 #include <iterator>
19 #include <cassert>
20 
21 #include "test_macros.h"
22 #include "types.h"
23 
24 void test() {
25   int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8};
26 
27   {
28     auto iter1 = random_access_iterator<int*>(buffer);
29     auto commonIter1 = std::common_iterator<decltype(iter1), sized_sentinel_type<int*>>(iter1);
30     auto commonSent1 = std::common_iterator<decltype(iter1), sized_sentinel_type<int*>>(sized_sentinel_type<int*>{buffer + 8});
31     assert(commonIter1 - commonSent1 == -8);
32     assert(commonSent1 - commonIter1 == 8);
33     assert(commonIter1 - commonIter1 == 0);
34     assert(commonSent1 - commonSent1 == 0);
35   }
36   {
37     auto iter1 = simple_iterator<int*>(buffer);
38     auto iter2 = comparable_iterator<int*>(buffer);
39     auto commonIter1 = std::common_iterator<decltype(iter1), sized_sentinel_type<int*>>(iter1);
40     auto commonIter2 = std::common_iterator<decltype(iter2), sized_sentinel_type<int*>>(iter2);
41 
42     assert(commonIter1 - commonIter2 == 0);
43   }
44   {
45     auto iter1 = random_access_iterator<int*>(buffer);
46     const auto commonIter1 = std::common_iterator<decltype(iter1), sized_sentinel_type<int*>>(iter1);
47     const auto commonSent1 = std::common_iterator<decltype(iter1), sized_sentinel_type<int*>>(sized_sentinel_type<int*>{buffer + 8});
48     assert(commonIter1 - commonSent1 == -8);
49     assert(commonSent1 - commonIter1 == 8);
50     assert(commonIter1 - commonIter1 == 0);
51     assert(commonSent1 - commonSent1 == 0);
52   }
53   {
54     auto iter1 = simple_iterator<int*>(buffer);
55     auto iter2 = comparable_iterator<int*>(buffer);
56     const auto commonIter1 = std::common_iterator<decltype(iter1), sized_sentinel_type<int*>>(iter1);
57     const auto commonIter2 = std::common_iterator<decltype(iter2), sized_sentinel_type<int*>>(iter2);
58 
59     assert(commonIter1 - commonIter2 == 0);
60   }
61 }
62 
63 int main(int, char**) {
64   test();
65 
66   return 0;
67 }
68