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-has-no-incomplete-ranges
11 
12 // friend constexpr decltype(auto) iter_move(const iterator& i);
13 
14 #include <cassert>
15 #include <ranges>
16 
17 #include "../types.h"
18 
test()19 constexpr bool test() {
20   int buffer[4][4] = {{1, 2, 3, 4}, {5, 6, 7, 8}, {9, 10, 11, 12}, {13, 14, 15, 16}};
21 
22   {
23     std::ranges::join_view jv(buffer);
24     assert(std::ranges::iter_move(jv.begin()) == 1);
25     static_assert(std::is_same_v<decltype(std::ranges::iter_move(jv.begin())), int&&>);
26 
27     static_assert(noexcept(std::ranges::iter_move(std::declval<decltype(jv.begin())>())));
28   }
29 
30   {
31     // iter_move calls inner's iter_move and calls
32     // iter_move on the correct inner iterator
33     IterMoveSwapAwareView inners[2] = {buffer[0], buffer[1]};
34     std::ranges::join_view jv(inners);
35     auto it = jv.begin();
36 
37     const auto& iter_move_called_times1 = jv.base().begin()->iter_move_called;
38     const auto& iter_move_called_times2 = std::next(jv.base().begin())->iter_move_called;
39     assert(iter_move_called_times1 == 0);
40     assert(iter_move_called_times2 == 0);
41 
42     std::same_as<std::pair<int&&, int&&>> decltype(auto) x = std::ranges::iter_move(it);
43     assert(std::get<0>(x) == 1);
44     assert(iter_move_called_times1 == 1);
45     assert(iter_move_called_times2 == 0);
46 
47     auto it2 = std::ranges::next(it, 4);
48 
49     std::same_as<std::pair<int&&, int&&>> decltype(auto) y = std::ranges::iter_move(it2);
50     assert(std::get<0>(y) == 5);
51     assert(iter_move_called_times1 == 1);
52     assert(iter_move_called_times2 == 1);
53   }
54   return true;
55 }
56 
main(int,char **)57 int main(int, char**) {
58   test();
59   static_assert(test());
60 
61   return 0;
62 }
63