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 split_view(View base, Pattern pattern); // explicit since C++23 |
12 | |
13 | #include <algorithm> |
14 | #include <cassert> |
15 | #include <ranges> |
16 | #include <string_view> |
17 | #include <utility> |
18 | |
19 | #include "test_convertible.h" |
20 | #include "test_macros.h" |
21 | |
22 | struct ViewWithCounting : std::ranges::view_base { |
23 | int* times_copied = nullptr; |
24 | int* times_moved = nullptr; |
25 | |
26 | constexpr ViewWithCounting(int& copies_ctr, int& moves_ctr) : times_copied(&copies_ctr), times_moved(&moves_ctr) {} |
27 | |
28 | constexpr ViewWithCounting(const ViewWithCounting& rhs) |
29 | : times_copied(rhs.times_copied), times_moved(rhs.times_moved) { |
30 | ++(*times_copied); |
31 | } |
32 | constexpr ViewWithCounting(ViewWithCounting&& rhs) : times_copied(rhs.times_copied), times_moved(rhs.times_moved) { |
33 | ++(*times_moved); |
34 | } |
35 | |
36 | constexpr const char* begin() const { return nullptr; } |
37 | constexpr const char* end() const { return nullptr; } |
38 | |
39 | constexpr ViewWithCounting& operator=(const ViewWithCounting&) = default; |
40 | constexpr ViewWithCounting& operator=(ViewWithCounting&&) = default; |
41 | constexpr bool operator==(const ViewWithCounting&) const { return true; } |
42 | }; |
43 | |
44 | using View = ViewWithCounting; |
45 | using Pattern = ViewWithCounting; |
46 | |
47 | // SFINAE tests. |
48 | |
49 | #if TEST_STD_VER >= 23 |
50 | |
51 | static_assert(!test_convertible<std::ranges::split_view<View, Pattern>, View, Pattern>(), |
52 | "This constructor must be explicit" ); |
53 | |
54 | #else |
55 | |
56 | static_assert( test_convertible<std::ranges::split_view<View, Pattern>, View, Pattern>(), |
57 | "This constructor must not be explicit" ); |
58 | |
59 | #endif // TEST_STD_VER >= 23 |
60 | |
61 | constexpr bool test() { |
62 | { |
63 | std::string_view input = "abc def" ; |
64 | std::ranges::split_view<std::string_view, std::string_view> v(input, " " ); |
65 | assert(v.base() == input); |
66 | assert(std::ranges::equal(*v.begin(), std::string_view{"abc" })); |
67 | } |
68 | |
69 | // Make sure the arguments are moved, not copied. |
70 | { |
71 | // Arguments are lvalues. |
72 | { |
73 | int view_copied = 0, view_moved = 0, pattern_copied = 0, pattern_moved = 0; |
74 | View view(view_copied, view_moved); |
75 | Pattern pattern(pattern_copied, pattern_moved); |
76 | |
77 | std::ranges::split_view<View, Pattern> v(view, pattern); |
78 | assert(view_copied == 1); // The local variable is copied into the argument. |
79 | assert(view_moved == 1); |
80 | assert(pattern_copied == 1); |
81 | assert(pattern_moved == 1); |
82 | } |
83 | |
84 | // Arguments are rvalues. |
85 | { |
86 | int view_copied = 0, view_moved = 0, pattern_copied = 0, pattern_moved = 0; |
87 | std::ranges::split_view<View, Pattern> v(View(view_copied, view_moved), Pattern(pattern_copied, pattern_moved)); |
88 | assert(view_copied == 0); |
89 | assert(view_moved == 1); |
90 | assert(pattern_copied == 0); |
91 | assert(pattern_moved == 1); |
92 | } |
93 | } |
94 | |
95 | return true; |
96 | } |
97 | |
98 | int main(int, char**) { |
99 | test(); |
100 | static_assert(test()); |
101 | |
102 | return 0; |
103 | } |
104 | |