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 // class std::ranges::subrange;
14 
15 #include <ranges>
16 
17 #include <cassert>
18 #include "test_macros.h"
19 #include "test_iterators.h"
20 
21 template<size_t I, class S>
22 concept HasGet = requires {
23   std::get<I>(std::declval<S>());
24 };
25 
26 static_assert( HasGet<0, std::ranges::subrange<int*>>);
27 static_assert( HasGet<1, std::ranges::subrange<int*>>);
28 static_assert(!HasGet<2, std::ranges::subrange<int*>>);
29 static_assert(!HasGet<3, std::ranges::subrange<int*>>);
30 
31 constexpr bool test() {
32   {
33     using It = int*;
34     using Sent = sentinel_wrapper<int*>;
35     int a[] = {1, 2, 3};
36     using R = std::ranges::subrange<It, Sent, std::ranges::subrange_kind::unsized>;
37     R r = R(It(a), Sent(It(a + 3)));
38     ASSERT_SAME_TYPE(decltype(std::get<0>(r)), It);
39     ASSERT_SAME_TYPE(decltype(std::get<1>(r)), Sent);
40     ASSERT_SAME_TYPE(decltype(std::get<0>(static_cast<R&&>(r))), It);
41     ASSERT_SAME_TYPE(decltype(std::get<1>(static_cast<R&&>(r))), Sent);
42     ASSERT_SAME_TYPE(decltype(std::get<0>(static_cast<const R&>(r))), It);
43     ASSERT_SAME_TYPE(decltype(std::get<1>(static_cast<const R&>(r))), Sent);
44     ASSERT_SAME_TYPE(decltype(std::get<0>(static_cast<const R&&>(r))), It);
45     ASSERT_SAME_TYPE(decltype(std::get<1>(static_cast<const R&&>(r))), Sent);
46     assert(base(std::get<0>(r)) == a);                      // copy from It
47     assert(base(base(std::get<1>(r))) == a + 3);            // copy from Sent
48     assert(base(std::get<0>(std::move(r))) == a);           // copy from It
49     assert(base(base(std::get<1>(std::move(r)))) == a + 3); // copy from Sent
50   }
51   {
52     using It = int*;
53     using Sent = sentinel_wrapper<int*>;
54     int a[] = {1, 2, 3};
55     using R = std::ranges::subrange<It, Sent, std::ranges::subrange_kind::sized>;
56     R r = R(It(a), Sent(It(a + 3)), 3);
57     ASSERT_SAME_TYPE(decltype(std::get<0>(r)), It);
58     ASSERT_SAME_TYPE(decltype(std::get<1>(r)), Sent);
59     ASSERT_SAME_TYPE(decltype(std::get<0>(static_cast<R&&>(r))), It);
60     ASSERT_SAME_TYPE(decltype(std::get<1>(static_cast<R&&>(r))), Sent);
61     ASSERT_SAME_TYPE(decltype(std::get<0>(static_cast<const R&>(r))), It);
62     ASSERT_SAME_TYPE(decltype(std::get<1>(static_cast<const R&>(r))), Sent);
63     ASSERT_SAME_TYPE(decltype(std::get<0>(static_cast<const R&&>(r))), It);
64     ASSERT_SAME_TYPE(decltype(std::get<1>(static_cast<const R&&>(r))), Sent);
65     assert(base(std::get<0>(r)) == a);                      // copy from It
66     assert(base(base(std::get<1>(r))) == a + 3);            // copy from Sent
67     assert(base(std::get<0>(std::move(r))) == a);           // copy from It
68     assert(base(base(std::get<1>(std::move(r)))) == a + 3); // copy from Sent
69   }
70   {
71     // Test the fix for LWG 3589.
72     using It = cpp20_input_iterator<int*>;
73     using Sent = sentinel_wrapper<It>;
74     int a[] = {1, 2, 3};
75     using R = std::ranges::subrange<It, Sent>;
76     R r = R(It(a), Sent(It(a + 3)));
77     static_assert(!HasGet<0, R&>);
78     ASSERT_SAME_TYPE(decltype(std::get<1>(r)), Sent);
79     ASSERT_SAME_TYPE(decltype(std::get<0>(static_cast<R&&>(r))), It);
80     ASSERT_SAME_TYPE(decltype(std::get<1>(static_cast<R&&>(r))), Sent);
81     static_assert(!HasGet<0, const R&>);
82     ASSERT_SAME_TYPE(decltype(std::get<1>(static_cast<const R&>(r))), Sent);
83     static_assert(!HasGet<0, const R&&>);
84     ASSERT_SAME_TYPE(decltype(std::get<1>(static_cast<const R&&>(r))), Sent);
85     assert(base(base(std::get<1>(r))) == a + 3);            // copy from Sent
86     assert(base(std::get<0>(std::move(r))) == a);           // move from It
87     assert(base(base(std::get<1>(std::move(r)))) == a + 3); // copy from Sent
88   }
89 
90   return true;
91 }
92 
93 int main(int, char**) {
94   test();
95   static_assert(test());
96 
97   return 0;
98 }
99