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 #include <algorithm>
12 #include <array>
13 #include <cassert>
14 #include <concepts>
15 #include <deque>
16 #include <ranges>
17 #include <vector>
18 
19 #include "test_iterators.h"
20 #include "type_algorithms.h"
21 
22 template <class InContainer, class OutContainer>
23 constexpr void test_containers() {
24   using InIter  = typename InContainer::iterator;
25   using OutIter = typename OutContainer::iterator;
26 
27   {
28     InContainer in{1, 2, 3, 4};
29     OutContainer out(4);
30 
31     std::same_as<std::ranges::in_out_result<InIter, OutIter>> auto ret =
32         std::ranges::copy(in.begin(), in.end(), out.begin());
33     assert(std::ranges::equal(in, out));
34     assert(ret.in == in.end());
35     assert(ret.out == out.end());
36   }
37   {
38     InContainer in{1, 2, 3, 4};
39     OutContainer out(4);
40     std::same_as<std::ranges::in_out_result<InIter, OutIter>> auto ret = std::ranges::copy(in, out.begin());
41     assert(std::ranges::equal(in, out));
42     assert(ret.in == in.end());
43     assert(ret.out == out.end());
44   }
45 }
46 
47 template <class Iter, class Sent>
48 constexpr void test_join_view() {
49   auto to_subranges = std::views::transform([](auto& vec) {
50     return std::ranges::subrange(Iter(vec.data()), Sent(Iter(vec.data() + vec.size())));
51   });
52 
53   { // segmented -> contiguous
54     std::vector<std::vector<int>> vectors = {};
55     auto range                            = vectors | to_subranges;
56     std::vector<std::ranges::subrange<Iter, Sent>> subrange_vector(range.begin(), range.end());
57     std::array<int, 0> arr;
58 
59     std::ranges::copy(subrange_vector | std::views::join, arr.begin());
60     assert(std::ranges::equal(arr, std::array<int, 0>{}));
61   }
62   { // segmented -> contiguous
63     std::vector<std::vector<int>> vectors = {{1, 2, 3, 4}, {5, 6, 7, 8}, {9, 10}, {}};
64     auto range                            = vectors | to_subranges;
65     std::vector<std::ranges::subrange<Iter, Sent>> subrange_vector(range.begin(), range.end());
66     std::array<int, 10> arr;
67 
68     std::ranges::copy(subrange_vector | std::views::join, arr.begin());
69     assert(std::ranges::equal(arr, std::array{1, 2, 3, 4, 5, 6, 7, 8, 9, 10}));
70   }
71   { // contiguous -> segmented
72     std::vector<std::vector<int>> vectors = {{0, 0, 0, 0}, {0, 0}, {0, 0, 0, 0}, {}};
73     auto range                            = vectors | to_subranges;
74     std::vector<std::ranges::subrange<Iter, Sent>> subrange_vector(range.begin(), range.end());
75     std::array arr = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
76 
77     std::ranges::copy(arr, (subrange_vector | std::views::join).begin());
78     assert(std::ranges::equal(subrange_vector | std::views::join, std::array{1, 2, 3, 4, 5, 6, 7, 8, 9, 10}));
79   }
80   { // segmented -> segmented
81     std::vector<std::vector<int>> vectors = {{1, 2, 3, 4}, {5, 6, 7, 8}, {9, 10}, {}};
82     auto range1                           = vectors | to_subranges;
83     std::vector<std::ranges::subrange<Iter, Sent>> subrange_vector(range1.begin(), range1.end());
84     std::vector<std::vector<int>> to_vectors = {{0, 0, 0, 0}, {0, 0, 0, 0}, {}, {0, 0}};
85     auto range2                              = to_vectors | to_subranges;
86     std::vector<std::ranges::subrange<Iter, Sent>> to_subrange_vector(range2.begin(), range2.end());
87 
88     std::ranges::copy(subrange_vector | std::views::join, (to_subrange_vector | std::views::join).begin());
89     assert(std::ranges::equal(to_subrange_vector | std::views::join, std::array{1, 2, 3, 4, 5, 6, 7, 8, 9, 10}));
90   }
91 }
92 
93 int main(int, char**) {
94   if (!std::is_constant_evaluated()) {
95     test_containers<std::deque<int>, std::deque<int>>();
96     test_containers<std::deque<int>, std::vector<int>>();
97     test_containers<std::vector<int>, std::deque<int>>();
98     test_containers<std::vector<int>, std::vector<int>>();
99   }
100 
101   meta::for_each(meta::forward_iterator_list<int*>{}, []<class Iter> {
102     test_join_view<Iter, Iter>();
103     test_join_view<Iter, sentinel_wrapper<Iter>>();
104     test_join_view<Iter, sized_sentinel<Iter>>();
105   });
106 
107   return 0;
108 }
109