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 // constexpr inner-iterator& inner-iterator::operator++();
12 //
13 // constexpr decltype(auto) inner-iterator::operator++(int);
14
15 #include <ranges>
16
17 #include <cassert>
18 #include <type_traits>
19 #include "test_macros.h"
20 #include "../types.h"
21
22 struct EmptyView : std::ranges::view_base {
beginEmptyView23 constexpr int* begin() const { return nullptr; }
endEmptyView24 constexpr int* end() const { return nullptr; }
sizeEmptyView25 constexpr static std::size_t size() { return 0; }
26 };
27 static_assert(std::ranges::forward_range<EmptyView>);
28 static_assert(std::ranges::view<EmptyView>);
29 LIBCPP_STATIC_ASSERT(std::ranges::__tiny_range<EmptyView>);
30
test()31 constexpr bool test() {
32 // Can call `inner-iterator::operator++`; `View` is a forward range.
33 {
34 SplitViewForward v("abc def", " ");
35 auto val = *v.begin();
36
37 // ++i
38 {
39 auto i = val.begin();
40 assert(*i == 'a');
41
42 decltype(auto) i2 = ++i;
43 static_assert(std::is_lvalue_reference_v<decltype(i2)>);
44 assert(&i2 == &i);
45 assert(*i2 == 'b');
46 }
47
48 // i++
49 {
50 auto i = val.begin();
51 assert(*i == 'a');
52
53 decltype(auto) i2 = i++;
54 static_assert(!std::is_reference_v<decltype(i2)>);
55 assert(*i2 == 'a');
56 assert(*i == 'b');
57 }
58 }
59
60 // Can call `inner-iterator::operator++`; `View` is an input range.
61 {
62 // ++i
63 {
64 SplitViewInput v("abc def", ' ');
65 auto val = *v.begin();
66
67 auto i = val.begin();
68 assert(*i == 'a');
69
70 decltype(auto) i2 = ++i;
71 static_assert(std::is_lvalue_reference_v<decltype(i2)>);
72 assert(&i2 == &i);
73 assert(*i2 == 'b');
74 }
75
76 // i++
77 {
78 SplitViewInput v("abc def", ' ');
79 auto val = *v.begin();
80
81 auto i = val.begin();
82 assert(*i == 'a');
83
84 static_assert(std::is_void_v<decltype(i++)>);
85 i++;
86 assert(*i == 'b');
87 }
88 }
89
90 // Can call `inner-iterator::operator++`; `View` is an input range and `Pattern` is an "empty" range.
91 {
92 // ++i
93 {
94 std::ranges::lazy_split_view<InputView, EmptyView> v("a", EmptyView());
95 auto val = *v.begin();
96
97 auto i = val.begin();
98 assert(*i.base() == 'a');
99 assert(i != std::default_sentinel);
100
101 // The iterator doesn't move to the next character but is considered to point to the end.
102 decltype(auto) i2 = ++i;
103 assert(&i2 == &i);
104 assert(*i2.base() == 'a');
105 assert(i2 == std::default_sentinel);
106 }
107
108 // i++
109 {
110 std::ranges::lazy_split_view<InputView, EmptyView> v("a", EmptyView());
111 auto val = *v.begin();
112
113 auto i = val.begin();
114 assert(*i.base() == 'a');
115 assert(i != std::default_sentinel);
116
117 // The iterator doesn't move to the next character but is considered to point to the end.
118 i++;
119 assert(*i.base() == 'a');
120 assert(i == std::default_sentinel);
121 }
122 }
123
124 return true;
125 }
126
main(int,char **)127 int main(int, char**) {
128 test();
129 static_assert(test());
130
131 return 0;
132 }
133