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 V base() const& requires copy_constructible<V>;
14 // constexpr V base() &&;
15 
16 #include <ranges>
17 
18 #include <cassert>
19 #include <utility>
20 
21 #include "test_macros.h"
22 #include "types.h"
23 
24 constexpr bool hasLValueQualifiedBase(auto&& view) {
25   return requires { view.base(); };
26 }
27 
28 constexpr bool test() {
29   int buf[8] = {1, 2, 3, 4, 5, 6, 7, 8};
30 
31   {
32     CopyableView view{buf, buf + 8};
33     std::ranges::common_view<CopyableView> common(view);
34     assert(common.base().begin_ == buf);
35     assert(std::move(common).base().begin_ == buf);
36 
37     ASSERT_SAME_TYPE(decltype(common.base()), CopyableView);
38     ASSERT_SAME_TYPE(decltype(std::move(common).base()), CopyableView);
39     static_assert(hasLValueQualifiedBase(common));
40   }
41 
42   {
43     MoveOnlyView view{buf, buf + 8};
44     std::ranges::common_view<MoveOnlyView> common(std::move(view));
45     assert(std::move(common).base().begin_ == buf);
46 
47     ASSERT_SAME_TYPE(decltype(std::move(common).base()), MoveOnlyView);
48     static_assert(!hasLValueQualifiedBase(common));
49   }
50 
51   {
52     CopyableView view{buf, buf + 8};
53     const std::ranges::common_view<CopyableView> common(view);
54     assert(common.base().begin_ == buf);
55     assert(std::move(common).base().begin_ == buf);
56 
57     ASSERT_SAME_TYPE(decltype(common.base()), CopyableView);
58     ASSERT_SAME_TYPE(decltype(std::move(common).base()), CopyableView);
59     static_assert(hasLValueQualifiedBase(common));
60   }
61 
62   return true;
63 }
64 
65 int main(int, char**) {
66   test();
67   static_assert(test());
68 
69   return 0;
70 }
71