xref: /llvm-project/libcxx/test/std/algorithms/alg.nonmodifying/alg.equal/ranges.equal.pass.cpp (revision b8cb1dc9ea87faa8e8e9ab7a31710a8c0bb8b084)
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 // <algorithm>
10 
11 // UNSUPPORTED: c++03, c++11, c++14, c++17
12 
13 // template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
14 //          class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
15 //   requires indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
16 //   constexpr bool ranges::equal(I1 first1, S1 last1, I2 first2, S2 last2,
17 //                                Pred pred = {},
18 //                                Proj1 proj1 = {}, Proj2 proj2 = {});
19 // template<input_range R1, input_range R2, class Pred = ranges::equal_to,
20 //          class Proj1 = identity, class Proj2 = identity>
21 //   requires indirectly_comparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
22 //   constexpr bool ranges::equal(R1&& r1, R2&& r2, Pred pred = {},
23 //                                Proj1 proj1 = {}, Proj2 proj2 = {});
24 
25 #include <algorithm>
26 #include <cassert>
27 #include <concepts>
28 #include <functional>
29 #include <ranges>
30 
31 #include "almost_satisfies_types.h"
32 #include "test_iterators.h"
33 
34 template <class Iter1, class Sent1 = sentinel_wrapper<Iter1>,
35           class Iter2 = Iter1, class Sent2 = sentinel_wrapper<Iter2>>
36 concept HasEqualIt = requires (Iter1 first1, Sent1 last1, Iter2 first2, Sent2 last2) {
37   std::ranges::equal(first1, last1, first2, last2);
38 };
39 
40 static_assert(HasEqualIt<int*>);
41 static_assert(!HasEqualIt<InputIteratorNotDerivedFrom>);
42 static_assert(!HasEqualIt<InputIteratorNotIndirectlyReadable>);
43 static_assert(!HasEqualIt<InputIteratorNotInputOrOutputIterator>);
44 static_assert(!HasEqualIt<int*, int*, InputIteratorNotDerivedFrom>);
45 static_assert(!HasEqualIt<int*, int*, InputIteratorNotIndirectlyReadable>);
46 static_assert(!HasEqualIt<int*, int*, InputIteratorNotInputOrOutputIterator>);
47 static_assert(!HasEqualIt<int*, SentinelForNotSemiregular>);
48 static_assert(!HasEqualIt<int*, SentinelForNotWeaklyEqualityComparableWith>);
49 static_assert(!HasEqualIt<int*, int*, int*, SentinelForNotSemiregular>);
50 static_assert(!HasEqualIt<int*, int*, int*, SentinelForNotWeaklyEqualityComparableWith>);
51 static_assert(!HasEqualIt<int*, int*, int**>);
52 
53 template <class Range1, class Range2>
54 concept HasEqualR = requires (Range1 range1, Range2 range2) {
55   std::ranges::equal(range1, range2);
56 };
57 
58 static_assert(HasEqualR<UncheckedRange<int*>, UncheckedRange<int*>>);
59 static_assert(!HasEqualR<InputRangeNotDerivedFrom, UncheckedRange<int*>>);
60 static_assert(!HasEqualR<InputRangeNotIndirectlyReadable, UncheckedRange<int*>>);
61 static_assert(!HasEqualR<InputRangeNotInputOrOutputIterator, UncheckedRange<int*>>);
62 static_assert(!HasEqualR<InputRangeNotSentinelSemiregular, UncheckedRange<int*>>);
63 static_assert(!HasEqualR<InputRangeNotSentinelEqualityComparableWith, UncheckedRange<int*>>);
64 static_assert(!HasEqualR<UncheckedRange<int*>, InputRangeNotDerivedFrom>);
65 static_assert(!HasEqualR<UncheckedRange<int*>, InputRangeNotIndirectlyReadable>);
66 static_assert(!HasEqualR<UncheckedRange<int*>, InputRangeNotInputOrOutputIterator>);
67 static_assert(!HasEqualR<UncheckedRange<int*>, InputRangeNotSentinelSemiregular>);
68 static_assert(!HasEqualR<UncheckedRange<int*>, InputRangeNotSentinelEqualityComparableWith>);
69 static_assert(!HasEqualR<UncheckedRange<int*>, UncheckedRange<int**>>);
70 
71 template <class Iter1, class Sent1, class Iter2, class Sent2 = Iter2>
72 constexpr void test_iterators() {
73   { // simple test
74     {
75       int a[] = {1, 2, 3, 4};
76       int b[] = {1, 2, 3, 4};
77       std::same_as<bool> decltype(auto) ret = std::ranges::equal(Iter1(a), Sent1(Iter1(a + 4)),
78                                                                  Iter2(b), Sent2(Iter2(b + 4)));
79       assert(ret);
80     }
81     {
82       int a[] = {1, 2, 3, 4};
83       int b[] = {1, 2, 3, 4};
84       auto range1 = std::ranges::subrange(Iter1(a), Sent1(Iter1(a + 4)));
85       auto range2 = std::ranges::subrange(Iter2(b), Sent2(Iter2(b + 4)));
86       std::same_as<bool> decltype(auto) ret = std::ranges::equal(range1, range2);
87       assert(ret);
88     }
89   }
90 
91   { // check that the predicate is used (return true)
92     {
93       int a[] = {1, 2, 3, 4};
94       int b[] = {2, 3, 4, 5};
95       auto ret = std::ranges::equal(Iter1(a), Sent1(Iter1(a + 4)), Iter2(b), Sent2(Iter2(b + 4)),
96                                     [](int l, int r) { return l != r; });
97       assert(ret);
98     }
99     {
100       int a[] = {1, 2, 3, 4};
101       int b[] = {2, 3, 4, 5};
102       auto range1 = std::ranges::subrange(Iter1(a), Sent1(Iter1(a + 4)));
103       auto range2 = std::ranges::subrange(Iter2(b), Sent2(Iter2(b + 4)));
104       auto ret = std::ranges::equal(range1, range2, [](int l, int r) { return l != r; });
105       assert(ret);
106     }
107   }
108 
109   { // check that the predicate is used (return false)
110     {
111       int a[] = {1, 2, 3, 4};
112       int b[] = {2, 3, 3, 5};
113       auto ret = std::ranges::equal(Iter1(a), Sent1(Iter1(a + 4)), Iter2(b), Sent2(Iter2(b + 4)),
114                                     [](int l, int r) { return l != r; });
115       assert(!ret);
116     }
117     {
118       int a[] = {1, 2, 3, 4};
119       int b[] = {2, 3, 3, 5};
120       auto range1 = std::ranges::subrange(Iter1(a), Sent1(Iter1(a + 4)));
121       auto range2 = std::ranges::subrange(Iter2(b), Sent2(Iter2(b + 4)));
122       auto ret = std::ranges::equal(range1, range2, [](int l, int r) { return l != r; });
123       assert(!ret);
124     }
125   }
126 
127   { // check that the projections are used
128     {
129       int a[] = {1, 2, 3, 4, 5};
130       int b[] = {6, 10, 14, 18, 22};
131       auto ret = std::ranges::equal(Iter1(a), Sent1(Iter1(a + 5)),
132                                     Iter2(b), Sent2(Iter2(b + 5)),
133                                     {},
134                                     [](int i) { return i * 4; },
135                                     [](int i) { return i - 2; });
136       assert(ret);
137     }
138     {
139       int a[] = {1, 2, 3, 4, 5};
140       int b[] = {6, 10, 14, 18, 22};
141       auto range1 = std::ranges::subrange(Iter1(a), Sent1(Iter1(a + 5)));
142       auto range2 = std::ranges::subrange(Iter2(b), Sent2(Iter2(b + 5)));
143       auto ret = std::ranges::equal(range1,
144                                     range2,
145                                     {},
146                                     [](int i) { return i * 4; },
147                                     [](int i) { return i - 2; });
148       assert(ret);
149     }
150   }
151 
152   { // check that different sized ranges work
153     {
154       int a[] = {4, 3, 2, 1};
155       int b[] = {4, 3, 2, 1, 5, 6, 7};
156       auto ret = std::ranges::equal(Iter1(a), Sent1(Iter1(a + 4)), Iter2(b), Sent2(Iter2(b + 7)));
157       assert(!ret);
158     }
159     {
160       int a[] = {4, 3, 2, 1};
161       int b[] = {4, 3, 2, 1, 5, 6, 7};
162       auto range1 = std::ranges::subrange(Iter1(a), Sent1(Iter1(a + 4)));
163       auto range2 = std::ranges::subrange(Iter2(b), Sent2(Iter2(b + 7)));
164       auto ret = std::ranges::equal(range1, range2);
165       assert(!ret);
166     }
167   }
168 
169   { // check that two ranges with the same size but different values are different
170     {
171       int a[] = {4, 6, 34, 76, 5};
172       int b[] = {4, 6, 34, 67, 5};
173       auto ret = std::ranges::equal(Iter1(a), Sent1(Iter1(a + 5)), Iter2(b), Sent2(Iter2(b + 5)));
174       assert(!ret);
175     }
176     {
177       int a[] = {4, 6, 34, 76, 5};
178       int b[] = {4, 6, 34, 67, 5};
179       auto range1 = std::ranges::subrange(Iter1(a), Sent1(Iter1(a + 5)));
180       auto range2 = std::ranges::subrange(Iter2(b), Sent2(Iter2(b + 5)));
181       auto ret = std::ranges::equal(range1, range2);
182       assert(!ret);
183     }
184   }
185 
186   { // check that two empty ranges work
187     {
188       int a[] = {};
189       int b[] = {};
190       auto ret = std::ranges::equal(Iter1(a), Sent1(Iter1(a)), Iter2(b), Sent2(Iter2(b)));
191       assert(ret);
192     }
193     {
194       int a[] = {};
195       int b[] = {};
196       auto range1 = std::ranges::subrange(Iter1(a), Sent1(Iter1(a)));
197       auto range2 = std::ranges::subrange(Iter2(b), Sent2(Iter2(b)));
198       auto ret = std::ranges::equal(range1, range2);
199       assert(ret);
200     }
201   }
202 
203   { // check that it works with the first range empty
204     {
205       int a[] = {};
206       int b[] = {1, 2};
207       auto ret = std::ranges::equal(Iter1(a), Sent1(Iter1(a)), Iter2(b), Sent2(Iter2(b + 2)));
208       assert(!ret);
209     }
210     {
211       int a[] = {};
212       int b[] = {1, 2};
213       auto range1 = std::ranges::subrange(Iter1(a), Sent1(Iter1(a)));
214       auto range2 = std::ranges::subrange(Iter2(b), Sent2(Iter2(b + 2)));
215       auto ret = std::ranges::equal(range1, range2);
216       assert(!ret);
217     }
218   }
219 
220   { // check that it works with the second range empty
221     {
222       int a[] = {1, 2};
223       int b[] = {};
224       auto ret = std::ranges::equal(Iter1(a), Sent1(Iter1(a + 2)), Iter2(b), Sent2(Iter2(b)));
225       assert(!ret);
226     }
227     {
228       int a[] = {1, 2};
229       int b[] = {};
230       auto range1 = std::ranges::subrange(Iter1(a), Sent1(Iter1(a + 2)));
231       auto range2 = std::ranges::subrange(Iter2(b), Sent2(Iter2(b)));
232       auto ret = std::ranges::equal(range1, range2);
233       assert(!ret);
234     }
235   }
236 }
237 
238 template<class Iter1, class Sent1 = Iter1>
239 constexpr void test_iterators2() {
240   test_iterators<Iter1, Sent1, cpp17_input_iterator<int*>, sentinel_wrapper<cpp17_input_iterator<int*>>>();
241   test_iterators<Iter1, Sent1, cpp20_input_iterator<int*>, sentinel_wrapper<cpp20_input_iterator<int*>>>();
242   test_iterators<Iter1, Sent1, forward_iterator<int*>>();
243   test_iterators<Iter1, Sent1, bidirectional_iterator<int*>>();
244   test_iterators<Iter1, Sent1, random_access_iterator<int*>>();
245   test_iterators<Iter1, Sent1, contiguous_iterator<int*>>();
246   test_iterators<Iter1, Sent1, int*>();
247   test_iterators<Iter1, Sent1, const int*>();
248 }
249 
250 constexpr bool test() {
251   test_iterators2<cpp17_input_iterator<int*>, sentinel_wrapper<cpp17_input_iterator<int*>>>();
252   test_iterators2<cpp20_input_iterator<int*>, sentinel_wrapper<cpp20_input_iterator<int*>>>();
253   test_iterators2<forward_iterator<int*>>();
254   test_iterators2<bidirectional_iterator<int*>>();
255   test_iterators2<random_access_iterator<int*>>();
256   test_iterators2<contiguous_iterator<int*>>();
257   test_iterators2<int*>();
258   test_iterators2<const int*>();
259 
260   { // check that std::invoke is used
261     struct S {
262       constexpr S(int i_) : i(i_) {}
263       constexpr bool equal(int o) { return i == o; }
264       constexpr S& identity() { return *this; }
265       int i;
266     };
267     {
268       S a[] = {7, 8, 9};
269       S b[] = {7, 8, 9};
270       auto ret = std::ranges::equal(a, a + 3, b, b + 3, &S::equal, &S::identity, &S::i);
271       assert(ret);
272     }
273     {
274       S a[] = {7, 8, 9};
275       S b[] = {7, 8, 9};
276       auto ret = std::ranges::equal(a, b, &S::equal, &S::identity, &S::i);
277       assert(ret);
278     }
279   }
280 
281   { // check that the complexity requirements are met
282     { // different size
283       {
284         int a[] = {1, 2, 3};
285         int b[] = {1, 2, 3, 4};
286         int predCount = 0;
287         int projCount = 0;
288         auto pred = [&](int l, int r) { ++predCount; return l == r; };
289         auto proj = [&](int i) { ++projCount; return i; };
290         auto ret = std::ranges::equal(a, a + 3, b, b + 4, pred, proj, proj);
291         assert(!ret);
292         assert(predCount == 0);
293         assert(projCount == 0);
294       }
295       {
296         int a[] = {1, 2, 3};
297         int b[] = {1, 2, 3, 4};
298         int predCount = 0;
299         int projCount = 0;
300         auto pred = [&](int l, int r) { ++predCount; return l == r; };
301         auto proj = [&](int i) { ++projCount; return i; };
302         auto ret = std::ranges::equal(a, b, pred, proj, proj);
303         assert(!ret);
304         assert(predCount == 0);
305         assert(projCount == 0);
306       }
307     }
308 
309     { // not a sized sentinel
310       {
311         int a[] = {1, 2, 3};
312         int b[] = {1, 2, 3, 4};
313         int predCount = 0;
314         int projCount = 0;
315         auto pred = [&](int l, int r) { ++predCount; return l == r; };
316         auto proj = [&](int i) { ++projCount; return i; };
317         auto ret = std::ranges::equal(a, sentinel_wrapper(a + 3), b, sentinel_wrapper(b + 4), pred, proj, proj);
318         assert(!ret);
319         assert(predCount <= 4);
320         assert(projCount <= 7);
321       }
322       {
323         int a[] = {1, 2, 3};
324         int b[] = {1, 2, 3, 4};
325         int predCount = 0;
326         int projCount = 0;
327         auto pred = [&](int l, int r) { ++predCount; return l == r; };
328         auto proj = [&](int i) { ++projCount; return i; };
329         auto range1 = std::ranges::subrange(a, sentinel_wrapper(a + 3));
330         auto range2 = std::ranges::subrange(b, sentinel_wrapper(b + 4));
331         auto ret = std::ranges::equal(range1, range2, pred, proj, proj);
332         assert(!ret);
333         assert(predCount <= 4);
334         assert(projCount <= 7);
335       }
336     }
337 
338     { // same size
339       {
340         int a[] = {1, 2, 3};
341         int b[] = {1, 2, 3};
342         int predCount = 0;
343         int projCount = 0;
344         auto pred = [&](int l, int r) { ++predCount; return l == r; };
345         auto proj = [&](int i) { ++projCount; return i; };
346         auto ret = std::ranges::equal(a, a + 3, b, b + 3, pred, proj, proj);
347         assert(ret);
348         assert(predCount == 3);
349         assert(projCount == 6);
350       }
351       {
352         int a[] = {1, 2, 3};
353         int b[] = {1, 2, 3};
354         int predCount = 0;
355         int projCount = 0;
356         auto pred = [&](int l, int r) { ++predCount; return l == r; };
357         auto proj = [&](int i) { ++projCount; return i; };
358         auto ret = std::ranges::equal(a, b, pred, proj, proj);
359         assert(ret);
360         assert(predCount == 3);
361         assert(projCount == 6);
362       }
363     }
364   }
365 
366   return true;
367 }
368 
369 int main(int, char**) {
370   test();
371   static_assert(test());
372 
373   return 0;
374 }
375