xref: /llvm-project/libcxx/test/std/algorithms/alg.modifying.operations/alg.move/ranges.move.pass.cpp (revision 520c7fbbd0356f135a19cc764ff70e7f52ba11a0) 
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 // UNSUPPORTED: GCC-ALWAYS_INLINE-FIXME
13 
14 // template<input_iterator I, sentinel_for<I> S, weakly_incrementable O>
15 //   requires indirectly_movable<I, O>
16 //   constexpr ranges::move_result<I, O>
17 //     ranges::move(I first, S last, O result);
18 // template<input_range R, weakly_incrementable O>
19 //   requires indirectly_movable<iterator_t<R>, O>
20 //   constexpr ranges::move_result<borrowed_iterator_t<R>, O>
21 //     ranges::move(R&& r, O result);
22 
23 #include <algorithm>
24 #include <array>
25 #include <cassert>
26 #include <deque>
27 #include <ranges>
28 #include <vector>
29 
30 #include "almost_satisfies_types.h"
31 #include "MoveOnly.h"
32 #include "test_iterators.h"
33 
34 template <class In, class Out = In, class Sent = sentinel_wrapper<In>>
35 concept HasMoveIt = requires(In in, Sent sent, Out out) { std::ranges::move(in, sent, out); };
36 
37 static_assert(HasMoveIt<int*>);
38 static_assert(!HasMoveIt<InputIteratorNotDerivedFrom>);
39 static_assert(!HasMoveIt<InputIteratorNotIndirectlyReadable>);
40 static_assert(!HasMoveIt<InputIteratorNotInputOrOutputIterator>);
41 static_assert(!HasMoveIt<int*, WeaklyIncrementableNotMovable>);
42 struct NotIndirectlyMovable {};
43 static_assert(!HasMoveIt<int*, NotIndirectlyMovable*>);
44 static_assert(!HasMoveIt<int*, int*, SentinelForNotSemiregular>);
45 static_assert(!HasMoveIt<int*, int*, SentinelForNotWeaklyEqualityComparableWith>);
46 
47 template <class Range, class Out>
48 concept HasMoveR = requires(Range range, Out out) { std::ranges::move(range, out); };
49 
50 static_assert(HasMoveR<std::array<int, 10>, int*>);
51 static_assert(!HasMoveR<InputRangeNotDerivedFrom, int*>);
52 static_assert(!HasMoveR<InputRangeNotIndirectlyReadable, int*>);
53 static_assert(!HasMoveR<InputRangeNotInputOrOutputIterator, int*>);
54 static_assert(!HasMoveR<WeaklyIncrementableNotMovable, int*>);
55 static_assert(!HasMoveR<UncheckedRange<NotIndirectlyMovable*>, int*>);
56 static_assert(!HasMoveR<InputRangeNotSentinelSemiregular, int*>);
57 static_assert(!HasMoveR<InputRangeNotSentinelEqualityComparableWith, int*>);
58 static_assert(!HasMoveR<UncheckedRange<int*>, WeaklyIncrementableNotMovable>);
59 
60 static_assert(std::is_same_v<std::ranges::move_result<int, long>, std::ranges::in_out_result<int, long>>);
61 
62 template <class In, class Out, class Sent, int N>
63 constexpr void test(std::array<int, N> in) {
64   {
65     std::array<int, N> out;
66     std::same_as<std::ranges::in_out_result<In, Out>> decltype(auto) ret =
67       std::ranges::move(In(in.data()), Sent(In(in.data() + in.size())), Out(out.data()));
68     assert(in == out);
69     assert(base(ret.in) == in.data() + in.size());
70     assert(base(ret.out) == out.data() + out.size());
71   }
72   {
73     std::array<int, N> out;
74     auto range = std::ranges::subrange(In(in.data()), Sent(In(in.data() + in.size())));
75     std::same_as<std::ranges::in_out_result<In, Out>> decltype(auto) ret =
76         std::ranges::move(range, Out(out.data()));
77     assert(in == out);
78     assert(base(ret.in) == in.data() + in.size());
79     assert(base(ret.out) == out.data() + out.size());
80   }
81 }
82 
83 template <class InContainer, class OutContainer, class In, class Out, class Sent = In>
84 constexpr void test_containers() {
85   {
86     InContainer in {1, 2, 3, 4};
87     OutContainer out(4);
88     std::same_as<std::ranges::in_out_result<In, Out>> auto ret =
89       std::ranges::move(In(in.begin()), Sent(In(in.end())), Out(out.begin()));
90     assert(std::ranges::equal(in, out));
91     assert(base(ret.in) == in.end());
92     assert(base(ret.out) == out.end());
93   }
94   {
95     InContainer in {1, 2, 3, 4};
96     OutContainer out(4);
97     auto range = std::ranges::subrange(In(in.begin()), Sent(In(in.end())));
98     std::same_as<std::ranges::in_out_result<In, Out>> auto ret = std::ranges::move(range, Out(out.begin()));
99     assert(std::ranges::equal(in, out));
100     assert(base(ret.in) == in.end());
101     assert(base(ret.out) == out.end());
102   }
103 }
104 
105 template <class In, class Out, class Sent = In>
106 constexpr void test_iterators() {
107   // simple test
108   test<In, Out, Sent, 4>({1, 2, 3, 4});
109   // check that an empty range works
110   test<In, Out, Sent, 0>({});
111 }
112 
113 template <template <class> class In, template <class> class Out>
114 constexpr void test_sentinels() {
115   test_iterators<In<int*>, Out<int*>>();
116   test_iterators<In<int*>, Out<int*>, sized_sentinel<In<int*>>>();
117   test_iterators<In<int*>, Out<int*>, sentinel_wrapper<In<int*>>>();
118 
119   if (!std::is_constant_evaluated()) {
120     if constexpr (!std::is_same_v<In<int*>, contiguous_iterator<int*>> &&
121                   !std::is_same_v<Out<int*>, contiguous_iterator<int*>> &&
122                   !std::is_same_v<In<int*>, ContiguousProxyIterator<int*>> &&
123                   !std::is_same_v<Out<int*>, ContiguousProxyIterator<int*>>) {
124       test_containers<std::deque<int>,
125                       std::deque<int>,
126                       In<std::deque<int>::iterator>,
127                       Out<std::deque<int>::iterator>>();
128       test_containers<std::deque<int>,
129                       std::vector<int>,
130                       In<std::deque<int>::iterator>,
131                       Out<std::vector<int>::iterator>>();
132       test_containers<std::vector<int>,
133                       std::deque<int>,
134                       In<std::vector<int>::iterator>,
135                       Out<std::deque<int>::iterator>>();
136       test_containers<std::vector<int>,
137                       std::vector<int>,
138                       In<std::vector<int>::iterator>,
139                       Out<std::vector<int>::iterator>>();
140     }
141   }
142 }
143 
144 template <template <class> class Out>
145 constexpr void test_in_iterators() {
146   test_iterators<cpp20_input_iterator<int*>, Out<int*>, sentinel_wrapper<cpp20_input_iterator<int*>>>();
147   test_sentinels<forward_iterator, Out>();
148   test_sentinels<bidirectional_iterator, Out>();
149   test_sentinels<random_access_iterator, Out>();
150   test_sentinels<contiguous_iterator, Out>();
151   test_sentinels<std::type_identity_t, Out>();
152 }
153 
154 template <template <class> class Out>
155 constexpr void test_proxy_in_iterators() {
156   test_iterators<ProxyIterator<cpp20_input_iterator<int*>>,
157                  Out<int*>,
158                  sentinel_wrapper<ProxyIterator<cpp20_input_iterator<int*>>>>();
159   test_sentinels<ForwardProxyIterator, Out>();
160   test_sentinels<BidirectionalProxyIterator, Out>();
161   test_sentinels<RandomAccessProxyIterator, Out>();
162   test_sentinels<ContiguousProxyIterator, Out>();
163   test_sentinels<ProxyIterator, Out>();
164 }
165 
166 struct IteratorWithMoveIter {
167   using value_type = int;
168   using difference_type = int;
169   explicit IteratorWithMoveIter() = default;
170   int* ptr;
171   constexpr IteratorWithMoveIter(int* ptr_) : ptr(ptr_) {}
172 
173   constexpr int& operator*() const; // iterator with iter_move should not be dereferenced
174 
175   constexpr IteratorWithMoveIter& operator++() { ++ptr; return *this; }
176   constexpr IteratorWithMoveIter operator++(int) { auto ret = *this; ++*this; return ret; }
177 
178   friend constexpr int iter_move(const IteratorWithMoveIter&) { return 42; }
179 
180   constexpr bool operator==(const IteratorWithMoveIter& other) const = default;
181 };
182 
183 // cpp17_intput_iterator has a defaulted template argument
184 template <class Iter>
185 using Cpp17InIter = cpp17_input_iterator<Iter>;
186 
187 constexpr bool test() {
188   test_in_iterators<cpp17_output_iterator>();
189   test_in_iterators<cpp20_output_iterator>();
190   test_in_iterators<Cpp17InIter>();
191   test_in_iterators<cpp20_input_iterator>();
192   test_in_iterators<forward_iterator>();
193   test_in_iterators<bidirectional_iterator>();
194   test_in_iterators<random_access_iterator>();
195   test_in_iterators<contiguous_iterator>();
196   test_in_iterators<std::type_identity_t>();
197 
198   test_proxy_in_iterators<Cpp20InputProxyIterator>();
199   test_proxy_in_iterators<ForwardProxyIterator>();
200   test_proxy_in_iterators<BidirectionalProxyIterator>();
201   test_proxy_in_iterators<RandomAccessProxyIterator>();
202   test_proxy_in_iterators<ContiguousProxyIterator>();
203   test_proxy_in_iterators<ProxyIterator>();
204 
205   { // check that a move-only type works
206     {
207       MoveOnly a[] = {1, 2, 3};
208       MoveOnly b[3];
209       std::ranges::move(a, std::begin(b));
210       assert(b[0].get() == 1);
211       assert(b[1].get() == 2);
212       assert(b[2].get() == 3);
213     }
214     {
215       MoveOnly a[] = {1, 2, 3};
216       MoveOnly b[3];
217       std::ranges::move(std::begin(a), std::end(a), std::begin(b));
218       assert(b[0].get() == 1);
219       assert(b[1].get() == 2);
220       assert(b[2].get() == 3);
221     }
222   }
223 
224   { // check that a move-only type works for ProxyIterator
225     {
226       MoveOnly a[] = {1, 2, 3};
227       MoveOnly b[3];
228       ProxyRange proxyA{a};
229       ProxyRange proxyB{b};
230       std::ranges::move(proxyA, std::begin(proxyB));
231       assert(b[0].get() == 1);
232       assert(b[1].get() == 2);
233       assert(b[2].get() == 3);
234     }
235     {
236       MoveOnly a[] = {1, 2, 3};
237       MoveOnly b[3];
238       ProxyRange proxyA{a};
239       ProxyRange proxyB{b};
240       std::ranges::move(std::begin(proxyA), std::end(proxyA), std::begin(proxyB));
241       assert(b[0].get() == 1);
242       assert(b[1].get() == 2);
243       assert(b[2].get() == 3);
244     }
245   }
246 
247   { // check that ranges::dangling is returned
248     std::array<int, 4> out;
249     std::same_as<std::ranges::in_out_result<std::ranges::dangling, int*>> decltype(auto) ret =
250       std::ranges::move(std::array {1, 2, 3, 4}, out.data());
251     assert(ret.out == out.data() + 4);
252     assert((out == std::array{1, 2, 3, 4}));
253   }
254 
255   { // check that an iterator is returned with a borrowing range
256     std::array in {1, 2, 3, 4};
257     std::array<int, 4> out;
258     std::same_as<std::ranges::in_out_result<int*, int*>> decltype(auto) ret =
259         std::ranges::move(std::views::all(in), out.data());
260     assert(ret.in == in.data() + 4);
261     assert(ret.out == out.data() + 4);
262     assert(in == out);
263   }
264 
265   { // check that every element is moved exactly once
266     struct MoveOnce {
267       bool moved = false;
268       constexpr MoveOnce() = default;
269       constexpr MoveOnce(const MoveOnce& other) = delete;
270       constexpr MoveOnce& operator=(MoveOnce&& other) {
271         assert(!other.moved);
272         moved = true;
273         return *this;
274       }
275     };
276     {
277       std::array<MoveOnce, 4> in {};
278       std::array<MoveOnce, 4> out {};
279       auto ret = std::ranges::move(in.begin(), in.end(), out.begin());
280       assert(ret.in == in.end());
281       assert(ret.out == out.end());
282       assert(std::all_of(out.begin(), out.end(), [](const auto& e) { return e.moved; }));
283     }
284     {
285       std::array<MoveOnce, 4> in {};
286       std::array<MoveOnce, 4> out {};
287       auto ret = std::ranges::move(in, out.begin());
288       assert(ret.in == in.end());
289       assert(ret.out == out.end());
290       assert(std::all_of(out.begin(), out.end(), [](const auto& e) { return e.moved; }));
291     }
292   }
293 
294   { // check that the range is moved forwards
295     struct OnlyForwardsMovable {
296       OnlyForwardsMovable* next = nullptr;
297       bool canMove = false;
298       OnlyForwardsMovable() = default;
299       constexpr OnlyForwardsMovable& operator=(OnlyForwardsMovable&&) {
300         assert(canMove);
301         if (next != nullptr)
302           next->canMove = true;
303         return *this;
304       }
305     };
306     {
307       std::array<OnlyForwardsMovable, 3> in {};
308       std::array<OnlyForwardsMovable, 3> out {};
309       out[0].next = &out[1];
310       out[1].next = &out[2];
311       out[0].canMove = true;
312       auto ret = std::ranges::move(in.begin(), in.end(), out.begin());
313       assert(ret.in == in.end());
314       assert(ret.out == out.end());
315       assert(out[0].canMove);
316       assert(out[1].canMove);
317       assert(out[2].canMove);
318     }
319     {
320       std::array<OnlyForwardsMovable, 3> in {};
321       std::array<OnlyForwardsMovable, 3> out {};
322       out[0].next = &out[1];
323       out[1].next = &out[2];
324       out[0].canMove = true;
325       auto ret = std::ranges::move(in, out.begin());
326       assert(ret.in == in.end());
327       assert(ret.out == out.end());
328       assert(out[0].canMove);
329       assert(out[1].canMove);
330       assert(out[2].canMove);
331     }
332   }
333 
334   { // check that iter_move is used properly
335     {
336       int a[] = {1, 2, 3, 4};
337       std::array<int, 4> b;
338       auto ret = std::ranges::move(IteratorWithMoveIter(a), IteratorWithMoveIter(a + 4), b.data());
339       assert(ret.in == a + 4);
340       assert(ret.out == b.data() + 4);
341       assert((b == std::array {42, 42, 42, 42}));
342     }
343     {
344       int a[] = {1, 2, 3, 4};
345       std::array<int, 4> b;
346       auto range = std::ranges::subrange(IteratorWithMoveIter(a), IteratorWithMoveIter(a + 4));
347       auto ret = std::ranges::move(range, b.data());
348       assert(ret.in == a + 4);
349       assert(ret.out == b.data() + 4);
350       assert((b == std::array {42, 42, 42, 42}));
351     }
352   }
353 
354   return true;
355 }
356 
357 int main(int, char**) {
358   test();
359   static_assert(test());
360 
361   return 0;
362 }
363