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 // template<BidirectionalIterator InIter, BidirectionalIterator OutIter>
12 // requires OutputIterator<OutIter, InIter::reference>
13 // constexpr OutIter // constexpr after C++17
14 // copy_backward(InIter first, InIter last, OutIter result);
15
16 #include <algorithm>
17 #include <cassert>
18
19 #include "test_macros.h"
20 #include "test_iterators.h"
21 #include "user_defined_integral.h"
22
23 template <class InIter, class OutIter>
24 TEST_CONSTEXPR_CXX20 void
test_copy_backward()25 test_copy_backward()
26 {
27 const unsigned N = 1000;
28 int ia[N] = {};
29 for (unsigned i = 0; i < N; ++i)
30 ia[i] = i;
31 int ib[N] = {0};
32
33 OutIter r = std::copy_backward(InIter(ia), InIter(ia+N), OutIter(ib+N));
34 assert(base(r) == ib);
35 for (unsigned i = 0; i < N; ++i)
36 assert(ia[i] == ib[i]);
37 }
38
39 TEST_CONSTEXPR_CXX20 bool
test()40 test()
41 {
42 test_copy_backward<bidirectional_iterator<const int*>, bidirectional_iterator<int*> >();
43 test_copy_backward<bidirectional_iterator<const int*>, random_access_iterator<int*> >();
44 test_copy_backward<bidirectional_iterator<const int*>, int*>();
45
46 test_copy_backward<random_access_iterator<const int*>, bidirectional_iterator<int*> >();
47 test_copy_backward<random_access_iterator<const int*>, random_access_iterator<int*> >();
48 test_copy_backward<random_access_iterator<const int*>, int*>();
49
50 test_copy_backward<const int*, bidirectional_iterator<int*> >();
51 test_copy_backward<const int*, random_access_iterator<int*> >();
52 test_copy_backward<const int*, int*>();
53
54 #if TEST_STD_VER > 17
55 test_copy_backward<contiguous_iterator<const int*>, bidirectional_iterator<int*>>();
56 test_copy_backward<contiguous_iterator<const int*>, random_access_iterator<int*>>();
57 test_copy_backward<contiguous_iterator<const int*>, int*>();
58
59 test_copy_backward<bidirectional_iterator<const int*>, contiguous_iterator<int*>>();
60 test_copy_backward<random_access_iterator<const int*>, contiguous_iterator<int*>>();
61 test_copy_backward<contiguous_iterator<const int*>, contiguous_iterator<int*>>();
62 test_copy_backward<const int*, contiguous_iterator<int*>>();
63 #endif
64
65 return true;
66 }
67
main(int,char **)68 int main(int, char**)
69 {
70 test();
71
72 #if TEST_STD_VER > 17
73 static_assert(test());
74 #endif
75
76 return 0;
77 }
78