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 
11 // template<class I2, class S2>
12 //   requires convertible_to<const I2&, I> && convertible_to<const S2&, S> &&
13 //            assignable_from<I&, const I2&> && assignable_from<S&, const S2&>
14 //     common_iterator& operator=(const common_iterator<I2, S2>& x);
15 
16 #include <iterator>
17 #include <ranges>
18 #include <cassert>
19 
20 #include "test_macros.h"
21 #include "types.h"
22 
23 void test() {
24   int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8};
25 
26   {
27     auto iter1 = cpp17_input_iterator<int*>(buffer);
28     auto commonIter1 = std::common_iterator<decltype(iter1), sentinel_type<int*>>(iter1);
29     auto commonIter2 = std::common_iterator<decltype(iter1), sentinel_type<int*>>(cpp17_input_iterator<int*>(buffer + 1));
30 
31     assert(*commonIter1 == 1);
32     assert(*commonIter2 == 2);
33     assert(commonIter1 != commonIter2);
34 
35     commonIter1 = commonIter2;
36 
37     assert(*commonIter1 == 2);
38     assert(*commonIter2 == 2);
39     assert(commonIter1 == commonIter2);
40   }
41   {
42     auto iter1 = forward_iterator<int*>(buffer);
43     auto commonIter1 = std::common_iterator<decltype(iter1), sentinel_type<int*>>(iter1);
44     auto commonIter2 = std::common_iterator<decltype(iter1), sentinel_type<int*>>(forward_iterator<int*>(buffer + 1));
45 
46     assert(*commonIter1 == 1);
47     assert(*commonIter2 == 2);
48     assert(commonIter1 != commonIter2);
49 
50     commonIter1 = commonIter2;
51 
52     assert(*commonIter1 == 2);
53     assert(*commonIter2 == 2);
54     assert(commonIter1 == commonIter2);
55   }
56   {
57     auto iter1 = random_access_iterator<int*>(buffer);
58     auto commonIter1 = std::common_iterator<decltype(iter1), sentinel_type<int*>>(iter1);
59     auto commonSent1 = std::common_iterator<decltype(iter1), sentinel_type<int*>>(sentinel_type<int*>{buffer + 8});
60 
61     auto commonIter2 = std::common_iterator<decltype(iter1), sentinel_type<int*>>(iter1 + 1);
62     auto commonSent2 = std::common_iterator<decltype(iter1), sentinel_type<int*>>(sentinel_type<int*>{buffer + 7});
63 
64     assert(*commonIter1 == 1);
65     assert(*commonIter2 == 2);
66     assert(commonIter1 != commonIter2);
67 
68     commonIter1 = commonIter2;
69 
70     assert(*commonIter1 == 2);
71     assert(*commonIter2 == 2);
72     assert(commonIter1 == commonIter2);
73 
74     assert(std::next(commonIter1, 6) != commonSent1);
75     assert(std::next(commonIter1, 6) == commonSent2);
76 
77     commonSent1 = commonSent2;
78 
79     assert(std::next(commonIter1, 6) == commonSent1);
80     assert(std::next(commonIter1, 6) == commonSent2);
81   }
82   {
83     auto iter1 = assignable_iterator<int*>(buffer);
84     auto iter2 = forward_iterator<int*>(buffer + 1);
85     auto commonIter1 = std::common_iterator<decltype(iter1), sentinel_type<int*>>(iter1);
86     auto commonSent1 = std::common_iterator<decltype(iter1), sentinel_type<int*>>(sentinel_type<int*>{buffer + 8});
87 
88     auto commonIter2 = std::common_iterator<decltype(iter2), sentinel_type<int*>>(iter2);
89     auto commonSent2 = std::common_iterator<decltype(iter2), sentinel_type<int*>>(sentinel_type<int*>{buffer + 7});
90 
91     assert(*commonIter1 == 1);
92     assert(*commonIter2 == 2);
93 
94     commonIter1 = commonIter2;
95 
96     assert(*commonIter1 == 2);
97     assert(*commonIter2 == 2);
98     assert(commonIter1 == commonIter2);
99 
100     assert(std::next(commonIter1, 6) != commonSent1);
101     assert(std::next(commonIter1, 6) == commonSent2);
102 
103     commonSent1 = commonSent2;
104 
105     assert(std::next(commonIter1, 6) == commonSent1);
106     assert(std::next(commonIter1, 6) == commonSent2);
107 
108     commonIter1 = commonSent1;
109 
110     assert(commonIter1 == commonSent2);
111 
112     commonIter1 = commonSent2;
113 
114     assert(commonIter1 == commonSent2);
115   }
116 #ifndef TEST_HAS_NO_EXCEPTIONS
117   {
118     auto iter1 = maybe_valueless_iterator<int*>(buffer);
119     auto iter2 = forward_iterator<int*>(buffer);
120     auto commonIter1 = std::common_iterator<decltype(iter1), sentinel_type<int*>>(iter1);
121     auto commonSent2 = std::common_iterator<decltype(iter1),
122       sentinel_throws_on_convert<int*>>(sentinel_throws_on_convert<int*>{buffer + 8});
123     auto commonIter2 = std::common_iterator<decltype(iter2), sentinel_type<int*>>(iter2);
124 
125     try {
126       commonIter1 = commonSent2;
127       assert(false);
128     } catch (int x) {
129       assert(x == 42);
130       commonIter1 = commonIter2;
131     }
132 
133     assert(*commonIter1 == 1);
134   }
135 #endif // TEST_HAS_NO_EXCEPTIONS
136 }
137 
138 int main(int, char**) {
139   test();
140 
141   return 0;
142 }
143