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 // class std::ranges::subrange;
13 
14 #include <ranges>
15 
16 #include <cassert>
17 #include "test_macros.h"
18 #include "test_iterators.h"
19 
20 template<size_t I, class S>
21 concept HasGet = requires {
22   std::get<I>(std::declval<S>());
23 };
24 
25 static_assert( HasGet<0, std::ranges::subrange<int*>>);
26 static_assert( HasGet<1, std::ranges::subrange<int*>>);
27 static_assert(!HasGet<2, std::ranges::subrange<int*>>);
28 static_assert(!HasGet<3, std::ranges::subrange<int*>>);
29 
test()30 constexpr bool test() {
31   {
32     using It = int*;
33     using Sent = sentinel_wrapper<int*>;
34     int a[] = {1, 2, 3};
35     using R = std::ranges::subrange<It, Sent, std::ranges::subrange_kind::unsized>;
36     R r = R(It(a), Sent(It(a + 3)));
37     ASSERT_SAME_TYPE(decltype(std::get<0>(r)), It);
38     ASSERT_SAME_TYPE(decltype(std::get<1>(r)), Sent);
39     ASSERT_SAME_TYPE(decltype(std::get<0>(static_cast<R&&>(r))), It);
40     ASSERT_SAME_TYPE(decltype(std::get<1>(static_cast<R&&>(r))), Sent);
41     ASSERT_SAME_TYPE(decltype(std::get<0>(static_cast<const R&>(r))), It);
42     ASSERT_SAME_TYPE(decltype(std::get<1>(static_cast<const R&>(r))), Sent);
43     ASSERT_SAME_TYPE(decltype(std::get<0>(static_cast<const R&&>(r))), It);
44     ASSERT_SAME_TYPE(decltype(std::get<1>(static_cast<const R&&>(r))), Sent);
45     assert(base(std::get<0>(r)) == a);                      // copy from It
46     assert(base(base(std::get<1>(r))) == a + 3);            // copy from Sent
47     assert(base(std::get<0>(std::move(r))) == a);           // copy from It
48     assert(base(base(std::get<1>(std::move(r)))) == a + 3); // copy from Sent
49   }
50   {
51     using It = int*;
52     using Sent = sentinel_wrapper<int*>;
53     int a[] = {1, 2, 3};
54     using R = std::ranges::subrange<It, Sent, std::ranges::subrange_kind::sized>;
55     R r = R(It(a), Sent(It(a + 3)), 3);
56     ASSERT_SAME_TYPE(decltype(std::get<0>(r)), It);
57     ASSERT_SAME_TYPE(decltype(std::get<1>(r)), Sent);
58     ASSERT_SAME_TYPE(decltype(std::get<0>(static_cast<R&&>(r))), It);
59     ASSERT_SAME_TYPE(decltype(std::get<1>(static_cast<R&&>(r))), Sent);
60     ASSERT_SAME_TYPE(decltype(std::get<0>(static_cast<const R&>(r))), It);
61     ASSERT_SAME_TYPE(decltype(std::get<1>(static_cast<const R&>(r))), Sent);
62     ASSERT_SAME_TYPE(decltype(std::get<0>(static_cast<const R&&>(r))), It);
63     ASSERT_SAME_TYPE(decltype(std::get<1>(static_cast<const R&&>(r))), Sent);
64     assert(base(std::get<0>(r)) == a);                      // copy from It
65     assert(base(base(std::get<1>(r))) == a + 3);            // copy from Sent
66     assert(base(std::get<0>(std::move(r))) == a);           // copy from It
67     assert(base(base(std::get<1>(std::move(r)))) == a + 3); // copy from Sent
68   }
69   {
70     // Test the fix for LWG 3589.
71     using It = cpp20_input_iterator<int*>;
72     using Sent = sentinel_wrapper<It>;
73     int a[] = {1, 2, 3};
74     using R = std::ranges::subrange<It, Sent>;
75     R r = R(It(a), Sent(It(a + 3)));
76     static_assert(!HasGet<0, R&>);
77     ASSERT_SAME_TYPE(decltype(std::get<1>(r)), Sent);
78     ASSERT_SAME_TYPE(decltype(std::get<0>(static_cast<R&&>(r))), It);
79     ASSERT_SAME_TYPE(decltype(std::get<1>(static_cast<R&&>(r))), Sent);
80     static_assert(!HasGet<0, const R&>);
81     ASSERT_SAME_TYPE(decltype(std::get<1>(static_cast<const R&>(r))), Sent);
82     static_assert(!HasGet<0, const R&&>);
83     ASSERT_SAME_TYPE(decltype(std::get<1>(static_cast<const R&&>(r))), Sent);
84     assert(base(base(std::get<1>(r))) == a + 3);            // copy from Sent
85     assert(base(std::get<0>(std::move(r))) == a);           // move from It
86     assert(base(base(std::get<1>(std::move(r)))) == a + 3); // copy from Sent
87   }
88 
89   return true;
90 }
91 
main(int,char **)92 int main(int, char**) {
93   test();
94   static_assert(test());
95 
96   return 0;
97 }
98