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
ViewWithCountingViewWithCounting26 constexpr ViewWithCounting(int& copies_ctr, int& moves_ctr) : times_copied(&copies_ctr), times_moved(&moves_ctr) {}
27
ViewWithCountingViewWithCounting28 constexpr ViewWithCounting(const ViewWithCounting& rhs)
29 : times_copied(rhs.times_copied), times_moved(rhs.times_moved) {
30 ++(*times_copied);
31 }
ViewWithCountingViewWithCounting32 constexpr ViewWithCounting(ViewWithCounting&& rhs) : times_copied(rhs.times_copied), times_moved(rhs.times_moved) {
33 ++(*times_moved);
34 }
35
beginViewWithCounting36 constexpr const char* begin() const { return nullptr; }
endViewWithCounting37 constexpr const char* end() const { return nullptr; }
38
39 constexpr ViewWithCounting& operator=(const ViewWithCounting&) = default;
40 constexpr ViewWithCounting& operator=(ViewWithCounting&&) = default;
operator ==ViewWithCounting41 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
test()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
main(int,char **)98 int main(int, char**) {
99 test();
100 static_assert(test());
101
102 return 0;
103 }
104