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 <input_range Range> |
12 | // requires constructible_from<View, views::all_t<Range>> && |
13 | // constructible_from<Pattern, single_view<range_value_t<Range>>> |
14 | // constexpr split_view(Range&& r, range_value_t<Range> e); // explicit since C++23 |
15 | |
16 | #include <algorithm> |
17 | #include <cassert> |
18 | #include <ranges> |
19 | #include <string> |
20 | #include <string_view> |
21 | #include <type_traits> |
22 | #include <utility> |
23 | |
24 | #include "test_convertible.h" |
25 | #include "test_macros.h" |
26 | |
27 | struct Counting { |
28 | int* times_copied = nullptr; |
29 | int* times_moved = nullptr; |
30 | |
31 | constexpr Counting(int& copies_ctr, int& moves_ctr) : times_copied(&copies_ctr), times_moved(&moves_ctr) {} |
32 | |
33 | constexpr Counting(const Counting& rhs) : times_copied(rhs.times_copied), times_moved(rhs.times_moved) { |
34 | ++(*times_copied); |
35 | } |
36 | constexpr Counting(Counting&& rhs) : times_copied(rhs.times_copied), times_moved(rhs.times_moved) { |
37 | ++(*times_moved); |
38 | } |
39 | |
40 | constexpr Counting& operator=(const Counting&) = default; |
41 | constexpr Counting& operator=(Counting&&) = default; |
42 | }; |
43 | |
44 | struct ElementWithCounting : Counting { |
45 | using Counting::Counting; |
46 | |
47 | constexpr bool operator==(const ElementWithCounting&) const { return true; } |
48 | }; |
49 | |
50 | struct RangeWithCounting : Counting { |
51 | using Counting::Counting; |
52 | |
53 | constexpr const ElementWithCounting* begin() const { return nullptr; } |
54 | constexpr const ElementWithCounting* end() const { return nullptr; } |
55 | |
56 | constexpr bool operator==(const RangeWithCounting&) const { return true; } |
57 | }; |
58 | static_assert(std::ranges::forward_range<RangeWithCounting>); |
59 | static_assert(!std::ranges::view<RangeWithCounting>); |
60 | |
61 | struct StrView : std::ranges::view_base { |
62 | std::string buffer_; |
63 | |
64 | template <std::ranges::range R> |
65 | constexpr StrView(R&& r) : buffer_(std::ranges::begin(r), std::ranges::end(r)) {} |
66 | constexpr const char* begin() const { return buffer_.data(); } |
67 | constexpr const char* end() const { return buffer_.data() + buffer_.size(); } |
68 | constexpr bool operator==(const StrView& rhs) const { return buffer_ == rhs.buffer_; } |
69 | }; |
70 | static_assert(std::ranges::random_access_range<StrView>); |
71 | static_assert(std::ranges::view<StrView>); |
72 | static_assert(std::is_copy_constructible_v<StrView>); |
73 | |
74 | // SFINAE tests. |
75 | |
76 | #if TEST_STD_VER >= 23 |
77 | |
78 | static_assert( |
79 | !test_convertible<std::ranges::split_view<StrView, StrView>, StrView, std::ranges::range_value_t<StrView>>(), |
80 | "This constructor must be explicit" ); |
81 | |
82 | # else |
83 | |
84 | static_assert( |
85 | test_convertible<std::ranges::split_view<StrView, StrView>, StrView, std::ranges::range_value_t<StrView>>(), |
86 | "This constructor must not be explicit" ); |
87 | |
88 | #endif // TEST_STD_VER >= 23 |
89 | |
90 | constexpr bool test() { |
91 | { |
92 | using V = std::ranges::split_view<StrView, StrView>; |
93 | |
94 | // Calling the constructor with `(std::string, range_value_t)`. |
95 | { |
96 | std::string input("abc def" ); |
97 | V v(input, ' '); |
98 | assert(v.base() == input); |
99 | assert(std::ranges::equal(*v.begin(), std::string_view("abc" ))); |
100 | } |
101 | |
102 | // Calling the constructor with `(StrView, range_value_t)`. |
103 | { |
104 | StrView input("abc def" ); |
105 | V v(input, ' '); |
106 | assert(v.base() == input); |
107 | assert(std::ranges::equal(*v.begin(), std::string_view("abc" ))); |
108 | } |
109 | |
110 | struct Empty {}; |
111 | static_assert(!std::is_constructible_v<V, Empty, std::string_view>); |
112 | static_assert(!std::is_constructible_v<V, std::string_view, Empty>); |
113 | } |
114 | |
115 | // Make sure the arguments are moved, not copied. |
116 | { |
117 | using Range = RangeWithCounting; |
118 | using Element = ElementWithCounting; |
119 | using Pattern = std::ranges::single_view<Element>; |
120 | |
121 | // Arguments are lvalues. |
122 | { |
123 | using View = std::ranges::ref_view<Range>; |
124 | |
125 | int range_copied = 0, range_moved = 0, element_copied = 0, element_moved = 0; |
126 | Range range(range_copied, range_moved); |
127 | Element element(element_copied, element_moved); |
128 | |
129 | std::ranges::split_view<View, Pattern> v(range, element); |
130 | assert(range_copied == 0); // `ref_view` does neither copy... |
131 | assert(range_moved == 0); // ...nor move the element. |
132 | assert(element_copied == 1); // The element is copied into the argument... |
133 | assert(element_moved == 1); // ...and moved into the member variable. |
134 | } |
135 | |
136 | // Arguments are rvalues. |
137 | { |
138 | using View = std::ranges::owning_view<Range>; |
139 | |
140 | int range_copied = 0, range_moved = 0, element_copied = 0, element_moved = 0; |
141 | std::ranges::split_view<View, Pattern> v( |
142 | Range(range_copied, range_moved), Element(element_copied, element_moved)); |
143 | assert(range_copied == 0); |
144 | assert(range_moved == 1); // `owning_view` moves the given argument. |
145 | assert(element_copied == 0); |
146 | assert(element_moved == 1); |
147 | } |
148 | } |
149 | |
150 | return true; |
151 | } |
152 | |
153 | int main(int, char**) { |
154 | test(); |
155 | static_assert(test()); |
156 | |
157 | return 0; |
158 | } |
159 | |