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 auto end();
14 // constexpr auto end() const requires range<const V>;
15 
16 #include <ranges>
17 #include <cassert>
18 
19 #include "test_macros.h"
20 #include "test_iterators.h"
21 #include "test_range.h"
22 
23 struct CopyableView : std::ranges::view_base {
24   int *ptr_;
25   constexpr CopyableView(int* ptr) : ptr_(ptr) {}
26   friend constexpr int* begin(CopyableView& view) { return view.ptr_; }
27   friend constexpr int* begin(CopyableView const& view) { return view.ptr_; }
28   friend constexpr sentinel_wrapper<int*> end(CopyableView& view) {
29     return sentinel_wrapper<int*>{view.ptr_ + 8};
30   }
31   friend constexpr sentinel_wrapper<int*> end(CopyableView const& view) {
32     return sentinel_wrapper<int*>{view.ptr_ + 8};
33   }
34 };
35 
36 using ForwardIter = forward_iterator<int*>;
37 struct SizedForwardView : std::ranges::view_base {
38   int *ptr_;
39   constexpr SizedForwardView(int* ptr) : ptr_(ptr) {}
40   friend constexpr ForwardIter begin(SizedForwardView& view) { return ForwardIter(view.ptr_); }
41   friend constexpr ForwardIter begin(SizedForwardView const& view) { return ForwardIter(view.ptr_); }
42   friend constexpr sentinel_wrapper<ForwardIter> end(SizedForwardView& view) {
43     return sentinel_wrapper<ForwardIter>{ForwardIter(view.ptr_ + 8)};
44   }
45   friend constexpr sentinel_wrapper<ForwardIter> end(SizedForwardView const& view) {
46     return sentinel_wrapper<ForwardIter>{ForwardIter(view.ptr_ + 8)};
47   }
48 };
49 
50 constexpr auto operator-(sentinel_wrapper<ForwardIter> sent, ForwardIter iter) {
51   return sent.base().base() - iter.base();
52 }
53 constexpr auto operator-(ForwardIter iter, sentinel_wrapper<ForwardIter> sent) {
54   return iter.base() - sent.base().base();
55 }
56 
57 using RandomAccessIter = random_access_iterator<int*>;
58 struct SizedRandomcAccessView : std::ranges::view_base {
59   int *ptr_;
60   constexpr SizedRandomcAccessView(int* ptr) : ptr_(ptr) {}
61   friend constexpr RandomAccessIter begin(SizedRandomcAccessView& view) { return RandomAccessIter(view.ptr_); }
62   friend constexpr RandomAccessIter begin(SizedRandomcAccessView const& view) { return RandomAccessIter(view.ptr_); }
63   friend constexpr sentinel_wrapper<RandomAccessIter> end(SizedRandomcAccessView& view) {
64     return sentinel_wrapper<RandomAccessIter>{RandomAccessIter(view.ptr_ + 8)};
65   }
66   friend constexpr sentinel_wrapper<RandomAccessIter> end(SizedRandomcAccessView const& view) {
67     return sentinel_wrapper<RandomAccessIter>{RandomAccessIter(view.ptr_ + 8)};
68   }
69 };
70 
71 constexpr auto operator-(sentinel_wrapper<RandomAccessIter> sent, RandomAccessIter iter) {
72   return sent.base().base() - iter.base();
73 }
74 constexpr auto operator-(RandomAccessIter iter, sentinel_wrapper<RandomAccessIter> sent) {
75   return iter.base() - sent.base().base();
76 }
77 
78 constexpr bool test() {
79   int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8};
80 
81   {
82     std::ranges::common_view<SizedRandomcAccessView> comm(SizedRandomcAccessView{buffer});
83     assert(comm.end().base() == buffer + 8);
84     // Note this should NOT be the sentinel type.
85     ASSERT_SAME_TYPE(decltype(comm.end()), RandomAccessIter);
86   }
87 
88   {
89     const std::ranges::common_view<SizedRandomcAccessView> comm(SizedRandomcAccessView{buffer});
90     assert(comm.end().base() == buffer + 8);
91     // Note this should NOT be the sentinel type.
92     ASSERT_SAME_TYPE(decltype(comm.end()), RandomAccessIter);
93   }
94 
95   return true;
96 }
97 
98 int main(int, char**) {
99   test();
100   static_assert(test());
101 
102   int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8};
103 
104   using CommonForwardIter = std::common_iterator<ForwardIter, sentinel_wrapper<ForwardIter>>;
105   using CommonIntIter = std::common_iterator<int*, sentinel_wrapper<int*>>;
106 
107   {
108     std::ranges::common_view<SizedForwardView> comm(SizedForwardView{buffer});
109     assert(comm.end() == CommonForwardIter(sentinel_wrapper<ForwardIter>(ForwardIter(buffer + 8))));
110     ASSERT_SAME_TYPE(decltype(comm.end()), CommonForwardIter);
111   }
112 
113   {
114     std::ranges::common_view<CopyableView> comm(CopyableView{buffer});
115     assert(comm.end() == CommonIntIter(sentinel_wrapper<int*>(buffer + 8)));
116     ASSERT_SAME_TYPE(decltype(comm.end()), CommonIntIter);
117   }
118 
119   {
120     const std::ranges::common_view<SizedForwardView> comm(SizedForwardView{buffer});
121     assert(comm.end() == CommonForwardIter(sentinel_wrapper<ForwardIter>(ForwardIter(buffer + 8))));
122     ASSERT_SAME_TYPE(decltype(comm.end()), CommonForwardIter);
123   }
124 
125   {
126     const std::ranges::common_view<CopyableView> comm(CopyableView{buffer});
127     assert(comm.end() == CommonIntIter(sentinel_wrapper<int*>(buffer + 8)));
128     ASSERT_SAME_TYPE(decltype(comm.end()), CommonIntIter);
129   }
130 
131   return 0;
132 }
133