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<sized_sentinel_for<I> I2, sized_sentinel_for<I> S2>
12 //   requires sized_sentinel_for<S, I2>
13 // friend iter_difference_t<I2> operator-(
14 //   const common_iterator& x, const common_iterator<I2, S2>& y);
15 
16 #include <iterator>
17 #include <cassert>
18 
19 #include "test_macros.h"
20 #include "types.h"
21 
22 void test() {
23   int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8};
24 
25   {
26     auto iter1 = random_access_iterator<int*>(buffer);
27     auto commonIter1 = std::common_iterator<decltype(iter1), sized_sentinel_type<int*>>(iter1);
28     auto commonSent1 = std::common_iterator<decltype(iter1), sized_sentinel_type<int*>>(sized_sentinel_type<int*>{buffer + 8});
29     assert(commonIter1 - commonSent1 == -8);
30     assert(commonSent1 - commonIter1 == 8);
31     assert(commonIter1 - commonIter1 == 0);
32     assert(commonSent1 - commonSent1 == 0);
33   }
34   {
35     auto iter1 = simple_iterator<int*>(buffer);
36     auto iter2 = comparable_iterator<int*>(buffer);
37     auto commonIter1 = std::common_iterator<decltype(iter1), sized_sentinel_type<int*>>(iter1);
38     auto commonIter2 = std::common_iterator<decltype(iter2), sized_sentinel_type<int*>>(iter2);
39 
40     assert(commonIter1 - commonIter2 == 0);
41   }
42   {
43     auto iter1 = random_access_iterator<int*>(buffer);
44     const auto commonIter1 = std::common_iterator<decltype(iter1), sized_sentinel_type<int*>>(iter1);
45     const auto commonSent1 = std::common_iterator<decltype(iter1), sized_sentinel_type<int*>>(sized_sentinel_type<int*>{buffer + 8});
46     assert(commonIter1 - commonSent1 == -8);
47     assert(commonSent1 - commonIter1 == 8);
48     assert(commonIter1 - commonIter1 == 0);
49     assert(commonSent1 - commonSent1 == 0);
50   }
51   {
52     auto iter1 = simple_iterator<int*>(buffer);
53     auto iter2 = comparable_iterator<int*>(buffer);
54     const auto commonIter1 = std::common_iterator<decltype(iter1), sized_sentinel_type<int*>>(iter1);
55     const auto commonIter2 = std::common_iterator<decltype(iter2), sized_sentinel_type<int*>>(iter2);
56 
57     assert(commonIter1 - commonIter2 == 0);
58   }
59 }
60 
61 int main(int, char**) {
62   test();
63 
64   return 0;
65 }
66