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 | // std::views::take_while |
12 | |
13 | #include <algorithm> |
14 | #include <cassert> |
15 | #include <ranges> |
16 | #include <type_traits> |
17 | #include <utility> |
18 | |
19 | #include "test_range.h" |
20 | #include "types.h" |
21 | |
22 | struct Pred { |
23 | constexpr bool operator()(int i) const { return i < 3; } |
24 | }; |
25 | |
26 | struct Foo {}; |
27 | |
28 | struct MoveOnlyView : IntBufferViewBase { |
29 | using IntBufferViewBase::IntBufferViewBase; |
30 | MoveOnlyView(const MoveOnlyView&) = delete; |
31 | MoveOnlyView& operator=(const MoveOnlyView&) = delete; |
32 | MoveOnlyView(MoveOnlyView&&) = default; |
33 | MoveOnlyView& operator=(MoveOnlyView&&) = default; |
34 | constexpr const int* begin() const { return buffer_; } |
35 | constexpr const int* end() const { return buffer_ + size_; } |
36 | }; |
37 | |
38 | static_assert(!std::is_invocable_v<decltype((std::views::take_while))>); |
39 | static_assert(std::is_invocable_v<decltype((std::views::take_while)), int>); |
40 | static_assert(std::is_invocable_v<decltype((std::views::take_while)), Pred>); |
41 | static_assert(!std::is_invocable_v<decltype((std::views::take_while)), int, Pred>); |
42 | static_assert(std::is_invocable_v<decltype((std::views::take_while)), int (&)[2], Pred>); |
43 | static_assert(!std::is_invocable_v<decltype((std::views::take_while)), Foo (&)[2], Pred>); |
44 | static_assert(std::is_invocable_v<decltype((std::views::take_while)), MoveOnlyView, Pred>); |
45 | |
46 | static_assert(!CanBePiped<MoveOnlyView, decltype(std::views::take_while)>); |
47 | static_assert(CanBePiped<MoveOnlyView, decltype(std::views::take_while(Pred{}))>); |
48 | static_assert(!CanBePiped<int, decltype(std::views::take_while(Pred{}))>); |
49 | static_assert(CanBePiped<int (&)[2], decltype(std::views::take_while(Pred{}))>); |
50 | static_assert(!CanBePiped<Foo (&)[2], decltype(std::views::take_while(Pred{}))>); |
51 | |
52 | constexpr bool test() { |
53 | int buff[] = {1, 2, 3, 4, 3, 2, 1}; |
54 | |
55 | // Test `views::take_while(p)(v)` |
56 | { |
57 | using Result = std::ranges::take_while_view<MoveOnlyView, Pred>; |
58 | std::same_as<Result> decltype(auto) result = std::views::take_while(Pred{})(MoveOnlyView{buff}); |
59 | auto expected = {1, 2}; |
60 | assert(std::ranges::equal(result, expected)); |
61 | } |
62 | { |
63 | auto const partial = std::views::take_while(Pred{}); |
64 | using Result = std::ranges::take_while_view<MoveOnlyView, Pred>; |
65 | std::same_as<Result> decltype(auto) result = partial(MoveOnlyView{buff}); |
66 | auto expected = {1, 2}; |
67 | assert(std::ranges::equal(result, expected)); |
68 | } |
69 | |
70 | // Test `v | views::take_while(p)` |
71 | { |
72 | using Result = std::ranges::take_while_view<MoveOnlyView, Pred>; |
73 | std::same_as<Result> decltype(auto) result = MoveOnlyView{buff} | std::views::take_while(Pred{}); |
74 | auto expected = {1, 2}; |
75 | assert(std::ranges::equal(result, expected)); |
76 | } |
77 | { |
78 | auto const partial = std::views::take_while(Pred{}); |
79 | using Result = std::ranges::take_while_view<MoveOnlyView, Pred>; |
80 | std::same_as<Result> decltype(auto) result = MoveOnlyView{buff} | partial; |
81 | auto expected = {1, 2}; |
82 | assert(std::ranges::equal(result, expected)); |
83 | } |
84 | |
85 | // Test `views::take_while(v, p)` |
86 | { |
87 | using Result = std::ranges::take_while_view<MoveOnlyView, Pred>; |
88 | std::same_as<Result> decltype(auto) result = std::views::take_while(MoveOnlyView{buff}, Pred{}); |
89 | auto expected = {1, 2}; |
90 | assert(std::ranges::equal(result, expected)); |
91 | } |
92 | |
93 | // Test adaptor | adaptor |
94 | { |
95 | struct Pred2 { |
96 | constexpr bool operator()(int i) const { return i < 2; } |
97 | }; |
98 | auto const partial = std::views::take_while(Pred{}) | std::views::take_while(Pred2{}); |
99 | using Result = std::ranges::take_while_view<std::ranges::take_while_view<MoveOnlyView, Pred>, Pred2>; |
100 | std::same_as<Result> decltype(auto) result = MoveOnlyView{buff} | partial; |
101 | auto expected = {1}; |
102 | assert(std::ranges::equal(result, expected)); |
103 | } |
104 | return true; |
105 | } |
106 | |
107 | int main(int, char**) { |
108 | test(); |
109 | static_assert(test()); |
110 | |
111 | return 0; |
112 | } |
113 | |