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// <algorithm>
12//
13// Range algorithms should return `std::ranges::dangling` when given a dangling range.
14
15#include <algorithm>
16
17#include <array>
18#include <concepts>
19#include <functional>
20#include <iterator>
21#include <numeric>
22#include <ranges>
23#include <random>
24#include <utility>
25
26#include "test_iterators.h"
27#include "test_macros.h"
28
29struct NonBorrowedRange {
30 using Iter = int*;
31 using Sent = sentinel_wrapper<Iter>;
32
33 int* data_;
34 std::size_t size_;
35
36 template <std::size_t N>
37 constexpr explicit NonBorrowedRange(std::array<int, N>& arr) : data_{arr.data()}, size_{arr.size()} {}
38
39 constexpr Iter begin() const { return data_; };
40 constexpr Sent end() const { return Sent{data_ + size_}; };
41};
42
43using R = NonBorrowedRange;
44
45// (dangling_in, ...)
46template <class ExpectedT = std::ranges::dangling, class Func, std::ranges::range Input, class ...Args>
47constexpr void dangling_1st(Func&& func, Input& in, Args&& ...args) {
48 decltype(auto) result = func(R(in), std::forward<Args>(args)...);
49 static_assert(std::same_as<decltype(result), ExpectedT>);
50}
51
52// (in, dangling_in, ...)
53template <class ExpectedT = std::ranges::dangling, class Func, std::ranges::range Input, class ...Args>
54constexpr void dangling_2nd(Func&& func, Input& in1, Input& in2, Args&& ...args) {
55 decltype(auto) result = func(in1, R(in2), std::forward<Args>(args)...);
56 static_assert(std::same_as<decltype(result), ExpectedT>);
57}
58
59// (dangling_in1, dangling_in2, ...)
60template <class ExpectedT = std::ranges::dangling, class Func, std::ranges::range Input, class ...Args>
61constexpr void dangling_both(Func&& func, Input& in1, Input& in2, Args&& ...args) {
62 decltype(auto) result = func(R(in1), R(in2), std::forward<Args>(args)...);
63 static_assert(std::same_as<decltype(result), ExpectedT>);
64}
65
66std::mt19937 rand_gen() { return std::mt19937(); }
67
68// TODO: also check the iterator values for algorithms that return `*_result` types.
69constexpr bool test_all() {
70 using std::ranges::dangling;
71
72 using std::ranges::binary_transform_result;
73 using std::ranges::copy_result;
74 using std::ranges::copy_backward_result;
75 using std::ranges::copy_if_result;
76 using std::ranges::for_each_result;
77 using std::ranges::merge_result;
78 using std::ranges::minmax_result;
79 using std::ranges::mismatch_result;
80 using std::ranges::move_result;
81 using std::ranges::move_backward_result;
82 using std::ranges::next_permutation_result;
83#if TEST_STD_VER >= 23
84 using std::ranges::out_value_result;
85#endif
86 using std::ranges::partial_sort_copy_result;
87 using std::ranges::partition_copy_result;
88 using std::ranges::prev_permutation_result;
89 using std::ranges::remove_copy_result;
90 using std::ranges::remove_copy_if_result;
91 using std::ranges::replace_copy_result;
92 using std::ranges::replace_copy_if_result;
93 using std::ranges::reverse_copy_result;
94 using std::ranges::rotate_copy_result;
95 using std::ranges::set_difference_result;
96 using std::ranges::set_intersection_result;
97 using std::ranges::set_symmetric_difference_result;
98 using std::ranges::set_union_result;
99 using std::ranges::swap_ranges_result;
100 using std::ranges::unary_transform_result;
101 using std::ranges::unique_copy_result;
102 using InIter = std::array<int, 3>::iterator;
103 using OutIter = std::array<int, 6>::iterator;
104
105 auto unary_pred = [](int i) { return i > 0; };
106 auto binary_pred = [](int i, int j) { return i < j; };
107 auto gen = [] { return 42; };
108
109 std::array in = {1, 2, 3};
110 std::array in2 = {4, 5, 6};
111
112 auto mid = in.data() + 1;
113
114 std::array output = {7, 8, 9, 10, 11, 12};
115 auto out = output.begin();
116 auto out2 = output.begin() + 1;
117
118 int x = 2;
119 std::size_t count = 1;
120
121 dangling_1st(std::ranges::find, in, x);
122 dangling_1st(std::ranges::find_if, in, unary_pred);
123 dangling_1st(std::ranges::find_if_not, in, unary_pred);
124#if TEST_STD_VER >= 23
125 dangling_1st(std::ranges::find_last, in, x);
126 dangling_1st(std::ranges::find_last_if, in, unary_pred);
127 dangling_1st(std::ranges::find_last_if_not, in, unary_pred);
128#endif
129 dangling_1st(std::ranges::find_first_of, in, in2);
130 dangling_1st(std::ranges::adjacent_find, in);
131 dangling_1st<mismatch_result<dangling, InIter>>(std::ranges::mismatch, in, in2);
132 dangling_2nd<mismatch_result<InIter, dangling>>(std::ranges::mismatch, in, in2);
133 dangling_both<mismatch_result<dangling, dangling>>(std::ranges::mismatch, in, in2);
134 dangling_1st(std::ranges::partition_point, in, unary_pred);
135 dangling_1st(std::ranges::lower_bound, in, x);
136 dangling_1st(std::ranges::upper_bound, in, x);
137 dangling_1st(std::ranges::equal_range, in, x);
138 dangling_1st(std::ranges::min_element, in);
139 dangling_1st(std::ranges::max_element, in);
140 dangling_1st<minmax_result<dangling>>(std::ranges::minmax_element, in);
141 dangling_1st(std::ranges::search, in, in2);
142 dangling_1st(std::ranges::search_n, in, count, x);
143 dangling_1st(std::ranges::find_end, in, in2);
144 dangling_1st(std::ranges::is_sorted_until, in);
145 dangling_1st(std::ranges::is_heap_until, in);
146 dangling_1st<for_each_result<dangling, decltype(unary_pred)>>(std::ranges::for_each, in, unary_pred);
147 dangling_1st<copy_result<dangling, OutIter>>(std::ranges::copy, in, out);
148 dangling_1st<copy_backward_result<dangling, OutIter>>(std::ranges::copy_backward, in, output.end());
149 dangling_1st<copy_if_result<dangling, OutIter>>(std::ranges::copy_if, in, out, unary_pred);
150 dangling_1st<move_result<dangling, OutIter>>(std::ranges::move, in, out);
151 dangling_1st<move_backward_result<dangling, OutIter>>(std::ranges::move_backward, in, output.end());
152 dangling_1st(std::ranges::fill, in, x);
153 { // transform
154 using OutTransformIter = std::array<bool, 3>::iterator;
155 std::array out_transform = {false, true, true};
156 dangling_1st<unary_transform_result<dangling, OutTransformIter>>(std::ranges::transform, in, out_transform.begin(), unary_pred);
157 dangling_1st<binary_transform_result<dangling, InIter, OutTransformIter>>(
158 std::ranges::transform, in, in2, out_transform.begin(), binary_pred);
159 dangling_2nd<binary_transform_result<InIter, dangling, OutTransformIter>>(
160 std::ranges::transform, in, in2, out_transform.begin(), binary_pred);
161 dangling_both<binary_transform_result<dangling, dangling, OutTransformIter>>(
162 std::ranges::transform, in, in2, out_transform.begin(), binary_pred);
163 }
164 dangling_1st(std::ranges::generate, in, gen);
165 dangling_1st<remove_copy_result<dangling, OutIter>>(std::ranges::remove_copy, in, out, x);
166 dangling_1st<remove_copy_if_result<dangling, OutIter>>(std::ranges::remove_copy_if, in, out, unary_pred);
167 dangling_1st(std::ranges::replace, in, x, x);
168 dangling_1st(std::ranges::replace_if, in, std::identity{}, x);
169 dangling_1st<replace_copy_result<dangling, OutIter>>(std::ranges::replace_copy, in, out, x, x);
170 dangling_1st<replace_copy_if_result<dangling, OutIter>>(std::ranges::replace_copy_if, in, out, unary_pred, x);
171 dangling_1st<swap_ranges_result<dangling, InIter>>(std::ranges::swap_ranges, in, in2);
172 dangling_2nd<swap_ranges_result<InIter, dangling>>(std::ranges::swap_ranges, in, in2);
173 dangling_both<swap_ranges_result<dangling, dangling>>(std::ranges::swap_ranges, in, in2);
174 dangling_1st<reverse_copy_result<dangling, OutIter>>(std::ranges::reverse_copy, in, out);
175 dangling_1st<rotate_copy_result<dangling, OutIter>>(std::ranges::rotate_copy, in, mid, out);
176 dangling_1st<unique_copy_result<dangling, OutIter>>(std::ranges::unique_copy, in, out);
177 dangling_1st<partition_copy_result<dangling, OutIter, OutIter>>(std::ranges::partition_copy, in, out, out2, unary_pred);
178 dangling_1st<partial_sort_copy_result<dangling, InIter>>(std::ranges::partial_sort_copy, in, in2);
179 dangling_2nd<partial_sort_copy_result<InIter, dangling>>(std::ranges::partial_sort_copy, in, in2);
180 dangling_both<partial_sort_copy_result<dangling, dangling>>(std::ranges::partial_sort_copy, in, in2);
181 dangling_1st<merge_result<dangling, InIter, OutIter>>(std::ranges::merge, in, in2, out);
182 dangling_2nd<merge_result<InIter, dangling, OutIter>>(std::ranges::merge, in, in2, out);
183 dangling_both<merge_result<dangling, dangling, OutIter>>(std::ranges::merge, in, in2, out);
184 dangling_1st<set_difference_result<dangling, OutIter>>(std::ranges::set_difference, in, in2, out);
185 dangling_1st<set_intersection_result<dangling, InIter, OutIter>>(std::ranges::set_intersection, in, in2, out);
186 dangling_2nd<set_intersection_result<InIter, dangling, OutIter>>(std::ranges::set_intersection, in, in2, out);
187 dangling_both<set_intersection_result<dangling, dangling, OutIter>>(std::ranges::set_intersection, in, in2, out);
188 dangling_1st<set_symmetric_difference_result<dangling, InIter, OutIter>>(
189 std::ranges::set_symmetric_difference, in, in2, out);
190 dangling_2nd<set_symmetric_difference_result<InIter, dangling, OutIter>>(
191 std::ranges::set_symmetric_difference, in, in2, out);
192 dangling_both<set_symmetric_difference_result<dangling, dangling, OutIter>>(
193 std::ranges::set_symmetric_difference, in, in2, out);
194 dangling_1st<set_union_result<dangling, InIter, OutIter>>(std::ranges::set_union, in, in2, out);
195 dangling_2nd<set_union_result<InIter, dangling, OutIter>>(std::ranges::set_union, in, in2, out);
196 dangling_both<set_union_result<dangling, dangling, OutIter>>(std::ranges::set_union, in, in2, out);
197 dangling_1st(std::ranges::remove, in, x);
198 dangling_1st(std::ranges::remove_if, in, unary_pred);
199 dangling_1st(std::ranges::reverse, in);
200 dangling_1st(std::ranges::rotate, in, mid);
201 if (!std::is_constant_evaluated()) // `shuffle` isn't `constexpr`.
202 dangling_1st(std::ranges::shuffle, in, rand_gen());
203 dangling_1st(std::ranges::unique, in);
204 dangling_1st(std::ranges::partition, in, unary_pred);
205 if (TEST_STD_AT_LEAST_26_OR_RUNTIME_EVALUATED) {
206 dangling_1st(std::ranges::stable_partition, in, unary_pred);
207 }
208 dangling_1st(std::ranges::sort, in);
209 if (TEST_STD_AT_LEAST_26_OR_RUNTIME_EVALUATED) {
210 dangling_1st(std::ranges::stable_sort, in);
211 }
212 dangling_1st(std::ranges::partial_sort, in, mid);
213 dangling_1st(std::ranges::nth_element, in, mid);
214 if (TEST_STD_AT_LEAST_26_OR_RUNTIME_EVALUATED) {
215 dangling_1st(std::ranges::inplace_merge, in, mid);
216 }
217 dangling_1st(std::ranges::make_heap, in);
218 dangling_1st(std::ranges::push_heap, in);
219 dangling_1st(std::ranges::pop_heap, in);
220 dangling_1st(std::ranges::make_heap, in);
221 dangling_1st(std::ranges::sort_heap, in);
222 dangling_1st<prev_permutation_result<dangling>>(std::ranges::prev_permutation, in);
223 dangling_1st<next_permutation_result<dangling>>(std::ranges::next_permutation, in);
224
225#if TEST_STD_VER >= 23
226 dangling_1st<out_value_result<dangling, decltype(x)>>(std::ranges::iota, in, x);
227#endif
228
229 return true;
230}
231
232int main(int, char**) {
233 test_all();
234 static_assert(test_all());
235
236 return 0;
237}
238

source code of libcxx/test/std/algorithms/ranges_robust_against_dangling.pass.cpp