xref: /llvm-project/libcxx/test/std/algorithms/alg.modifying.operations/alg.copy/copy_n.pass.cpp (revision cc89063bff0f73ec7049a1dcb5d4688ae6806941)
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<InputIterator InIter, OutputIterator<auto, InIter::reference> OutIter>
12 //   constexpr OutIter   // constexpr after C++17
13 //   copy_n(InIter first, InIter::difference_type n, OutIter result);
14 
15 #include <algorithm>
16 #include <cassert>
17 
18 #include "test_macros.h"
19 #include "test_iterators.h"
20 #include "user_defined_integral.h"
21 
22 // #if TEST_STD_VER > 17
23 // TEST_CONSTEXPR bool test_constexpr() {
24 //     int ia[] = {1, 2, 3, 4, 5};
25 //     int ic[] = {6, 6, 6, 6, 6, 6, 6};
26 //
27 //     auto p = std::copy_n(std::begin(ia), 4, std::begin(ic));
28 //     return std::equal(std::begin(ic), p, std::begin(ia))
29 //         && std::all_of(p, std::end(ic), [](int a){return a == 6;})
30 //         ;
31 //     }
32 // #endif
33 
34 typedef UserDefinedIntegral<unsigned> UDI;
35 
36 template <class InIter, class OutIter>
37 void
38 test()
39 {
40     const unsigned N = 1000;
41     int ia[N];
42     for (unsigned i = 0; i < N; ++i)
43         ia[i] = i;
44     int ib[N] = {0};
45 
46     OutIter r = std::copy_n(InIter(ia), UDI(N/2), OutIter(ib));
47     assert(base(r) == ib+N/2);
48     for (unsigned i = 0; i < N/2; ++i)
49         assert(ia[i] == ib[i]);
50 }
51 
52 int main(int, char**)
53 {
54     test<input_iterator<const int*>, output_iterator<int*> >();
55     test<input_iterator<const int*>, input_iterator<int*> >();
56     test<input_iterator<const int*>, forward_iterator<int*> >();
57     test<input_iterator<const int*>, bidirectional_iterator<int*> >();
58     test<input_iterator<const int*>, random_access_iterator<int*> >();
59     test<input_iterator<const int*>, int*>();
60 
61     test<forward_iterator<const int*>, output_iterator<int*> >();
62     test<forward_iterator<const int*>, input_iterator<int*> >();
63     test<forward_iterator<const int*>, forward_iterator<int*> >();
64     test<forward_iterator<const int*>, bidirectional_iterator<int*> >();
65     test<forward_iterator<const int*>, random_access_iterator<int*> >();
66     test<forward_iterator<const int*>, int*>();
67 
68     test<bidirectional_iterator<const int*>, output_iterator<int*> >();
69     test<bidirectional_iterator<const int*>, input_iterator<int*> >();
70     test<bidirectional_iterator<const int*>, forward_iterator<int*> >();
71     test<bidirectional_iterator<const int*>, bidirectional_iterator<int*> >();
72     test<bidirectional_iterator<const int*>, random_access_iterator<int*> >();
73     test<bidirectional_iterator<const int*>, int*>();
74 
75     test<random_access_iterator<const int*>, output_iterator<int*> >();
76     test<random_access_iterator<const int*>, input_iterator<int*> >();
77     test<random_access_iterator<const int*>, forward_iterator<int*> >();
78     test<random_access_iterator<const int*>, bidirectional_iterator<int*> >();
79     test<random_access_iterator<const int*>, random_access_iterator<int*> >();
80     test<random_access_iterator<const int*>, int*>();
81 
82     test<const int*, output_iterator<int*> >();
83     test<const int*, input_iterator<int*> >();
84     test<const int*, forward_iterator<int*> >();
85     test<const int*, bidirectional_iterator<int*> >();
86     test<const int*, random_access_iterator<int*> >();
87     test<const int*, int*>();
88 
89 // #if TEST_STD_VER > 17
90 //     static_assert(test_constexpr());
91 // #endif
92 
93   return 0;
94 }
95