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 | // template<forward_iterator I, sentinel_for<I> S, class T, class Proj = identity, |
12 | // indirect_strict_weak_order<const T*, projected<I, Proj>> Comp = ranges::less> |
13 | // constexpr I ranges::upper_bound(I first, S last, const T& value, Comp comp = {}, Proj proj = {}); |
14 | // template<forward_range R, class T, class Proj = identity, |
15 | // indirect_strict_weak_order<const T*, projected<iterator_t<R>, Proj>> Comp = |
16 | // ranges::less> |
17 | // constexpr borrowed_iterator_t<R> |
18 | // ranges::upper_bound(R&& r, const T& value, Comp comp = {}, Proj proj = {}); |
19 | |
20 | #include <algorithm> |
21 | #include <array> |
22 | #include <cassert> |
23 | #include <functional> |
24 | #include <ranges> |
25 | |
26 | #include "almost_satisfies_types.h" |
27 | #include "test_iterators.h" |
28 | |
29 | struct NotLessThanComparable {}; |
30 | |
31 | template <class It, class Sent = It> |
32 | concept HasUpperBoundIt = requires(It it, Sent sent) { std::ranges::upper_bound(it, sent, 1); }; |
33 | |
34 | static_assert(HasUpperBoundIt<int*>); |
35 | static_assert(!HasUpperBoundIt<cpp20_input_iterator<int*>, sentinel_wrapper<cpp20_input_iterator<int*>>>); |
36 | static_assert(!HasUpperBoundIt<ForwardIteratorNotDerivedFrom>); |
37 | static_assert(!HasUpperBoundIt<ForwardIteratorNotIncrementable>); |
38 | static_assert(!HasUpperBoundIt<NotLessThanComparable*>); |
39 | |
40 | template <class Range> |
41 | concept HasUpperBoundR = requires(Range range) { std::ranges::upper_bound(range, 1); }; |
42 | |
43 | static_assert(HasUpperBoundR<std::array<int, 1>>); |
44 | static_assert(!HasUpperBoundR<ForwardRangeNotDerivedFrom>); |
45 | static_assert(!HasUpperBoundR<ForwardRangeNotIncrementable>); |
46 | static_assert(!HasUpperBoundR<UncheckedRange<NotLessThanComparable*>>); |
47 | |
48 | template <class Pred> |
49 | concept HasUpperBoundPred = requires(int* it, Pred pred) {std::ranges::upper_bound(it, it, 1, pred); }; |
50 | |
51 | static_assert(HasUpperBoundPred<std::ranges::less>); |
52 | static_assert(!HasUpperBoundPred<IndirectUnaryPredicateNotCopyConstructible>); |
53 | static_assert(!HasUpperBoundPred<IndirectUnaryPredicateNotPredicate>); |
54 | |
55 | template <class It> |
56 | constexpr void test_iterators() { |
57 | { // simple test |
58 | { |
59 | int a[] = {1, 2, 3, 4, 5, 6}; |
60 | std::same_as<It> auto ret = std::ranges::upper_bound(It(a), It(a + 6), 3); |
61 | assert(base(ret) == a + 3); |
62 | } |
63 | { |
64 | int a[] = {1, 2, 3, 4, 5, 6}; |
65 | auto range = std::ranges::subrange(It(a), It(a + 6)); |
66 | std::same_as<It> auto ret = std::ranges::upper_bound(range, 3); |
67 | assert(base(ret) == a + 3); |
68 | } |
69 | } |
70 | |
71 | { // check that the predicate is used |
72 | { |
73 | int a[] = {6, 5, 4, 3, 2, 1}; |
74 | auto ret = std::ranges::upper_bound(It(a), It(a + 6), 2, std::ranges::greater{}); |
75 | assert(base(ret) == a + 5); |
76 | } |
77 | { |
78 | int a[] = {6, 5, 4, 3, 2, 1}; |
79 | auto range = std::ranges::subrange(It(a), It(a + 6)); |
80 | auto ret = std::ranges::upper_bound(range, 2, std::ranges::greater{}); |
81 | assert(base(ret) == a + 5); |
82 | } |
83 | } |
84 | |
85 | { // check that the projection is used |
86 | { |
87 | int a[] = {1, 2, 3, 4, 5, 6}; |
88 | auto ret = std::ranges::upper_bound(It(a), It(a + 6), 0, {}, [](int i) { return i - 3; }); |
89 | assert(base(ret) == a + 3); |
90 | } |
91 | { |
92 | int a[] = {1, 2, 3, 4, 5, 6}; |
93 | auto range = std::ranges::subrange(It(a), It(a + 6)); |
94 | auto ret = std::ranges::upper_bound(range, 0, {}, [](int i) { return i - 3; }); |
95 | assert(base(ret) == a + 3); |
96 | } |
97 | } |
98 | |
99 | { // check that the last upper bound is returned |
100 | { |
101 | int a[] = {1, 2, 2, 2, 3}; |
102 | auto ret = std::ranges::upper_bound(It(a), It(a + 5), 2); |
103 | assert(base(ret) == a + 4); |
104 | } |
105 | { |
106 | int a[] = {1, 2, 2, 2, 3}; |
107 | auto range = std::ranges::subrange(It(a), It(a + 5)); |
108 | auto ret = std::ranges::upper_bound(range, 2); |
109 | assert(base(ret) == a + 4); |
110 | } |
111 | } |
112 | |
113 | { // check that end is returned if all elements compare less than |
114 | { |
115 | int a[] = {1, 2, 3, 4}; |
116 | auto ret = std::ranges::upper_bound(It(a), It(a + 4), 5); |
117 | assert(base(ret) == a + 4); |
118 | } |
119 | { |
120 | int a[] = {1, 2, 3, 4}; |
121 | auto range = std::ranges::subrange(It(a), It(a + 4)); |
122 | auto ret = std::ranges::upper_bound(range, 5); |
123 | assert(base(ret) == a + 4); |
124 | } |
125 | } |
126 | |
127 | { // check that the first element is returned if no element compares less than |
128 | { |
129 | int a[] = {1, 2, 3, 4}; |
130 | auto ret = std::ranges::upper_bound(It(a), It(a + 4), 0); |
131 | assert(base(ret) == a); |
132 | } |
133 | { |
134 | int a[] = {1, 2, 3, 4}; |
135 | auto range = std::ranges::subrange(It(a), It(a + 4)); |
136 | auto ret = std::ranges::upper_bound(range, 0); |
137 | assert(base(ret) == a); |
138 | } |
139 | } |
140 | |
141 | { // check that a single element works |
142 | { |
143 | int a[] = {1}; |
144 | auto ret = std::ranges::upper_bound(It(a), It(a + 1), 1); |
145 | assert(base(ret) == a + 1); |
146 | } |
147 | { |
148 | int a[] = {1}; |
149 | auto range = std::ranges::subrange(It(a), It(a + 1)); |
150 | auto ret = std::ranges::upper_bound(range, 1); |
151 | assert(base(ret) == a + 1); |
152 | } |
153 | } |
154 | |
155 | { // check that an even number of elements works |
156 | { |
157 | int a[] = {1, 3, 6, 6, 7, 8}; |
158 | auto ret = std::ranges::upper_bound(It(a), It(a + 6), 6); |
159 | assert(base(ret) == a + 4); |
160 | } |
161 | { |
162 | int a[] = {1, 3, 6, 6, 7, 8}; |
163 | auto range = std::ranges::subrange(It(a), It(a + 6)); |
164 | auto ret = std::ranges::upper_bound(range, 6); |
165 | assert(base(ret) == a + 4); |
166 | } |
167 | } |
168 | |
169 | { // check that an odd number of elements works |
170 | { |
171 | int a[] = {1, 3, 6, 6, 7}; |
172 | auto ret = std::ranges::upper_bound(It(a), It(a + 5), 6); |
173 | assert(base(ret) == a + 4); |
174 | } |
175 | { |
176 | int a[] = {1, 3, 6, 6, 7}; |
177 | auto range = std::ranges::subrange(It(a), It(a + 5)); |
178 | auto ret = std::ranges::upper_bound(range, 6); |
179 | assert(base(ret) == a + 4); |
180 | } |
181 | } |
182 | |
183 | { // check that it works when all but the searched for element are equal |
184 | { |
185 | int a[] = {1, 6, 6, 6, 6, 6}; |
186 | auto ret = std::ranges::upper_bound(It(a), It(a + 6), 1); |
187 | assert(base(ret) == a + 1); |
188 | } |
189 | { |
190 | int a[] = {1, 6, 6, 6, 6, 6}; |
191 | auto range = std::ranges::subrange(It(a), It(a + 6)); |
192 | auto ret = std::ranges::upper_bound(range, 1); |
193 | assert(base(ret) == a + 1); |
194 | } |
195 | } |
196 | |
197 | { // check that the middle of a range is returned when there are smaller and larger elements |
198 | { |
199 | int a[] = {1, 2, 3, 4, 6, 7, 8}; |
200 | auto ret = std::ranges::upper_bound(It(a), It(a + 7), 5); |
201 | assert(base(ret) == a + 4); |
202 | assert(*ret == 6); |
203 | } |
204 | { |
205 | int a[] = {1, 2, 3, 4, 6, 7, 8}; |
206 | auto range = std::ranges::subrange(It(a), It(a + 7)); |
207 | auto ret = std::ranges::upper_bound(range, 5); |
208 | assert(base(ret) == a + 4); |
209 | assert(*ret == 6); |
210 | } |
211 | } |
212 | } |
213 | |
214 | constexpr bool test() { |
215 | test_iterators<int*>(); |
216 | test_iterators<forward_iterator<int*>>(); |
217 | test_iterators<bidirectional_iterator<int*>>(); |
218 | test_iterators<random_access_iterator<int*>>(); |
219 | test_iterators<contiguous_iterator<int*>>(); |
220 | |
221 | { // check that std::invoke is used for the projections |
222 | { |
223 | struct S { int check; int other; }; |
224 | S a[] = {{.check: 1, .other: 6}, {.check: 2, .other: 5}, {.check: 3, .other: 4}, {.check: 4, .other: 3}, {.check: 5, .other: 2}, {.check: 6, .other: 1}}; |
225 | auto ret = std::ranges::upper_bound(a, a + 6, 4, {}, &S::check); |
226 | assert(ret == a + 4); |
227 | } |
228 | { |
229 | struct S { int check; int other; }; |
230 | S a[] = {{.check: 1, .other: 6}, {.check: 2, .other: 5}, {.check: 3, .other: 4}, {.check: 4, .other: 3}, {.check: 5, .other: 2}, {.check: 6, .other: 1}}; |
231 | auto ret = std::ranges::upper_bound(a, 4, {}, &S::check); |
232 | assert(ret == a + 4); |
233 | } |
234 | } |
235 | |
236 | { // check that std::invoke is used for the predicate |
237 | struct S { |
238 | int check; |
239 | int other; |
240 | |
241 | constexpr bool compare(const S& s) const { |
242 | return check < s.check; |
243 | } |
244 | }; |
245 | { |
246 | S a[] = {{.check: 1, .other: 6}, {.check: 2, .other: 5}, {.check: 3, .other: 4}, {.check: 4, .other: 3}, {.check: 5, .other: 2}, {.check: 6, .other: 1}}; |
247 | auto ret = std::ranges::upper_bound(a, a + 6, S{4, 0}, &S::compare); |
248 | assert(ret == a + 4); |
249 | } |
250 | { |
251 | S a[] = {{.check: 1, .other: 6}, {.check: 2, .other: 5}, {.check: 3, .other: 4}, {.check: 4, .other: 3}, {.check: 5, .other: 2}, {.check: 6, .other: 1}}; |
252 | auto ret = std::ranges::upper_bound(a, S{4, 0}, &S::compare); |
253 | assert(ret == a + 4); |
254 | } |
255 | } |
256 | |
257 | { // check that an empty range works |
258 | { |
259 | std::array<int, 0> a; |
260 | auto ret = std::ranges::upper_bound(a.begin(), a.end(), 1); |
261 | assert(ret == a.end()); |
262 | } |
263 | { |
264 | std::array<int, 0> a; |
265 | auto ret = std::ranges::upper_bound(a, 1); |
266 | assert(ret == a.end()); |
267 | } |
268 | } |
269 | |
270 | { // check that ranges::dangling is returned |
271 | [[maybe_unused]] std::same_as<std::ranges::dangling> auto ret = std::ranges::upper_bound(std::array{1, 2}, 1); |
272 | } |
273 | |
274 | { // check that an iterator is returned with a borrowing range |
275 | int a[] = {1, 2, 3}; |
276 | std::same_as<int*> auto ret = std::ranges::upper_bound(std::views::all(a), 1); |
277 | assert(ret == a + 1); |
278 | } |
279 | |
280 | return true; |
281 | } |
282 | |
283 | int main(int, char**) { |
284 | test(); |
285 | static_assert(test()); |
286 | |
287 | return 0; |
288 | } |
289 | |