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: libcpp-has-no-incomplete-ranges
12 
13 // constexpr iterator& operator++();
14 // constexpr void operator++(int);
15 // constexpr iterator operator++(int) requires incrementable<W>;
16 
17 #include <ranges>
18 #include <cassert>
19 
20 #include "test_macros.h"
21 #include "../types.h"
22 
23 constexpr bool test() {
24   {
25     std::ranges::iota_view<int> io(0);
26     auto iter1 = io.begin();
27     auto iter2 = io.begin();
28     assert(iter1 == iter2);
29     assert(++iter1 != iter2++);
30     assert(iter1 == iter2);
31 
32     static_assert(!std::is_reference_v<decltype(iter2++)>);
33     static_assert( std::is_reference_v<decltype(++iter2)>);
34     static_assert(std::same_as<std::remove_reference_t<decltype(++iter2)>, decltype(iter2++)>);
35   }
36   {
37     std::ranges::iota_view io(SomeInt(0));
38     auto iter1 = io.begin();
39     auto iter2 = io.begin();
40     assert(iter1 == iter2);
41     assert(++iter1 != iter2++);
42     assert(iter1 == iter2);
43 
44     static_assert(!std::is_reference_v<decltype(iter2++)>);
45     static_assert( std::is_reference_v<decltype(++iter2)>);
46     static_assert(std::same_as<std::remove_reference_t<decltype(++iter2)>, decltype(iter2++)>);
47   }
48 
49   {
50     std::ranges::iota_view<NotIncrementable> io(NotIncrementable(0));
51     auto iter1 = io.begin();
52     auto iter2 = io.begin();
53     assert(iter1 == iter2);
54     assert(++iter1 != iter2);
55     iter2++;
56     assert(iter1 == iter2);
57 
58     static_assert(std::same_as<decltype(iter2++), void>);
59     static_assert(std::is_reference_v<decltype(++iter2)>);
60   }
61 
62   return true;
63 }
64 
65 int main(int, char**) {
66   test();
67   static_assert(test());
68 
69   return 0;
70 }
71