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: gcc-10
12 // UNSUPPORTED: libcpp-has-no-incomplete-ranges
13 
14 // constexpr auto end();
15 // constexpr auto end() const requires range<const V>;
16 
17 #include <ranges>
18 #include <cassert>
19 
20 #include "test_macros.h"
21 #include "test_iterators.h"
22 #include "test_range.h"
23 
24 struct CopyableView : std::ranges::view_base {
25   int *ptr_;
26   constexpr CopyableView(int* ptr) : ptr_(ptr) {}
27   friend constexpr int* begin(CopyableView& view) { return view.ptr_; }
28   friend constexpr int* begin(CopyableView const& view) { return view.ptr_; }
29   friend constexpr sentinel_wrapper<int*> end(CopyableView& view) {
30     return sentinel_wrapper<int*>{view.ptr_ + 8};
31   }
32   friend constexpr sentinel_wrapper<int*> end(CopyableView const& view) {
33     return sentinel_wrapper<int*>{view.ptr_ + 8};
34   }
35 };
36 
37 using ForwardIter = forward_iterator<int*>;
38 struct SizedForwardView : std::ranges::view_base {
39   int *ptr_;
40   constexpr SizedForwardView(int* ptr) : ptr_(ptr) {}
41   friend constexpr ForwardIter begin(SizedForwardView& view) { return ForwardIter(view.ptr_); }
42   friend constexpr ForwardIter begin(SizedForwardView const& view) { return ForwardIter(view.ptr_); }
43   friend constexpr sentinel_wrapper<ForwardIter> end(SizedForwardView& view) {
44     return sentinel_wrapper<ForwardIter>{ForwardIter(view.ptr_ + 8)};
45   }
46   friend constexpr sentinel_wrapper<ForwardIter> end(SizedForwardView const& view) {
47     return sentinel_wrapper<ForwardIter>{ForwardIter(view.ptr_ + 8)};
48   }
49 };
50 
51 constexpr auto operator-(sentinel_wrapper<ForwardIter> sent, ForwardIter iter) {
52   return sent.base().base() - iter.base();
53 }
54 constexpr auto operator-(ForwardIter iter, sentinel_wrapper<ForwardIter> sent) {
55   return iter.base() - sent.base().base();
56 }
57 
58 using RandomAccessIter = random_access_iterator<int*>;
59 struct SizedRandomcAccessView : std::ranges::view_base {
60   int *ptr_;
61   constexpr SizedRandomcAccessView(int* ptr) : ptr_(ptr) {}
62   friend constexpr RandomAccessIter begin(SizedRandomcAccessView& view) { return RandomAccessIter(view.ptr_); }
63   friend constexpr RandomAccessIter begin(SizedRandomcAccessView const& view) { return RandomAccessIter(view.ptr_); }
64   friend constexpr sentinel_wrapper<RandomAccessIter> end(SizedRandomcAccessView& view) {
65     return sentinel_wrapper<RandomAccessIter>{RandomAccessIter(view.ptr_ + 8)};
66   }
67   friend constexpr sentinel_wrapper<RandomAccessIter> end(SizedRandomcAccessView const& view) {
68     return sentinel_wrapper<RandomAccessIter>{RandomAccessIter(view.ptr_ + 8)};
69   }
70 };
71 
72 constexpr auto operator-(sentinel_wrapper<RandomAccessIter> sent, RandomAccessIter iter) {
73   return sent.base().base() - iter.base();
74 }
75 constexpr auto operator-(RandomAccessIter iter, sentinel_wrapper<RandomAccessIter> sent) {
76   return iter.base() - sent.base().base();
77 }
78 
79 constexpr bool test() {
80   int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8};
81 
82   {
83     std::ranges::common_view<SizedRandomcAccessView> comm(SizedRandomcAccessView{buffer});
84     assert(comm.end().base() == buffer + 8);
85     // Note this should NOT be the sentinel type.
86     ASSERT_SAME_TYPE(decltype(comm.end()), RandomAccessIter);
87   }
88 
89   {
90     const std::ranges::common_view<SizedRandomcAccessView> comm(SizedRandomcAccessView{buffer});
91     assert(comm.end().base() == buffer + 8);
92     // Note this should NOT be the sentinel type.
93     ASSERT_SAME_TYPE(decltype(comm.end()), RandomAccessIter);
94   }
95 
96   return true;
97 }
98 
99 int main(int, char**) {
100   test();
101   static_assert(test());
102 
103   int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8};
104 
105   using CommonForwardIter = std::common_iterator<ForwardIter, sentinel_wrapper<ForwardIter>>;
106   using CommonIntIter = std::common_iterator<int*, sentinel_wrapper<int*>>;
107 
108   {
109     std::ranges::common_view<SizedForwardView> comm(SizedForwardView{buffer});
110     assert(comm.end() == CommonForwardIter(sentinel_wrapper<ForwardIter>(ForwardIter(buffer + 8))));
111     ASSERT_SAME_TYPE(decltype(comm.end()), CommonForwardIter);
112   }
113 
114   {
115     std::ranges::common_view<CopyableView> comm(CopyableView{buffer});
116     assert(comm.end() == CommonIntIter(sentinel_wrapper<int*>(buffer + 8)));
117     ASSERT_SAME_TYPE(decltype(comm.end()), CommonIntIter);
118   }
119 
120   {
121     const std::ranges::common_view<SizedForwardView> comm(SizedForwardView{buffer});
122     assert(comm.end() == CommonForwardIter(sentinel_wrapper<ForwardIter>(ForwardIter(buffer + 8))));
123     ASSERT_SAME_TYPE(decltype(comm.end()), CommonForwardIter);
124   }
125 
126   {
127     const std::ranges::common_view<CopyableView> comm(CopyableView{buffer});
128     assert(comm.end() == CommonIntIter(sentinel_wrapper<int*>(buffer + 8)));
129     ASSERT_SAME_TYPE(decltype(comm.end()), CommonIntIter);
130   }
131 
132   return 0;
133 }
134