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
22template <class InContainer, class OutContainer>
23constexpr 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::move_backward(in.begin(), in.end(), out.end());
33 assert(std::ranges::equal(in, out));
34 assert(ret.in == in.end());
35 assert(ret.out == out.begin());
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::move_backward(in, out.end());
41 assert(std::ranges::equal(in, out));
42 assert(ret.in == in.end());
43 assert(ret.out == out.begin());
44 }
45}
46
47template <class Iter, class Sent>
48constexpr 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::move_backward(subrange_vector | std::views::join, arr.end());
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::move_backward(subrange_vector | std::views::join, arr.end());
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::move_backward(arr, (subrange_vector | std::views::join).end());
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::move_backward(subrange_vector | std::views::join, (to_subrange_vector | std::views::join).end());
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
93constexpr bool test_constexpr() {
94 test_containers<std::vector<int>, std::vector<int>>();
95
96 types::for_each(types::bidirectional_iterator_list<int*>{}, []<class Iter> { test_join_view<Iter, Iter>(); });
97 return true;
98}
99
100int main(int, char**) {
101 test_containers<std::deque<int>, std::deque<int>>();
102 test_containers<std::deque<int>, std::vector<int>>();
103 test_containers<std::vector<int>, std::deque<int>>();
104
105 test_constexpr();
106 static_assert(test_constexpr());
107
108 return 0;
109}
110

source code of libcxx/test/std/algorithms/alg.modifying.operations/alg.move/ranges.move_backward.segmented.pass.cpp