xref: /llvm-project/libcxx/test/std/algorithms/alg.sorting/alg.merge/merge_comp.pass.cpp (revision 5e97d37b960840cabf32dfef3503b28ba5d21dc2)
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 InIter1, InputIterator InIter2, typename OutIter,
12 //          CopyConstructible Compare>
13 //   requires OutputIterator<OutIter, InIter1::reference>
14 //         && OutputIterator<OutIter, InIter2::reference>
15 //         && Predicate<Compare, InIter1::value_type, InIter2::value_type>
16 //         && Predicate<Compare, InIter2::value_type, InIter1::value_type>
17 //   constexpr OutIter       // constexpr after C++17
18 //   merge(InIter1 first1, InIter1 last1, InIter2 first2, InIter2 last2,
19 //         OutIter result, Compare comp);
20 
21 #include <algorithm>
22 #include <cassert>
23 
24 #include "test_macros.h"
25 #include "test_iterators.h"
26 #include "../sortable_helpers.h"
27 
28 template<class T, class Iter1, class Iter2, class OutIter>
test4()29 TEST_CONSTEXPR_CXX20 void test4()
30 {
31     const T a[] = {11, 33, 31, 41};
32     const T b[] = {22, 32, 43, 42, 52};
33     {
34         T result[20] = {};
35         T expected[] = {11, 22, 33, 31, 32, 41, 43, 42, 52};
36         OutIter end = std::merge(Iter1(a), Iter1(a+4), Iter2(b), Iter2(b+5), OutIter(result), typename T::Comparator());
37         assert(std::lexicographical_compare(result, base(end), expected, expected+9, T::less) == 0);
38         for (const T *it = base(end); it != result+20; ++it) {
39             assert(it->value == 0);
40         }
41     }
42     {
43         T result[20] = {};
44         T expected[] = {11, 22, 32, 33, 31, 43, 42, 41, 52};
45         OutIter end = std::merge(Iter1(b), Iter1(b+5), Iter2(a), Iter2(a+4), OutIter(result), typename T::Comparator());
46         assert(std::lexicographical_compare(result, base(end), expected, expected+9, T::less) == 0);
47         for (const T *it = base(end); it != result+20; ++it) {
48             assert(it->value == 0);
49         }
50     }
51 }
52 
53 template<class T, class Iter1, class Iter2>
test3()54 TEST_CONSTEXPR_CXX20 void test3()
55 {
56     test4<T, Iter1, Iter2, cpp17_output_iterator<T*> >();
57     test4<T, Iter1, Iter2, forward_iterator<T*> >();
58     test4<T, Iter1, Iter2, bidirectional_iterator<T*> >();
59     test4<T, Iter1, Iter2, random_access_iterator<T*> >();
60     test4<T, Iter1, Iter2, T*>();
61 }
62 
63 template<class T, class Iter1>
test2()64 TEST_CONSTEXPR_CXX20 void test2()
65 {
66     test3<T, Iter1, cpp17_input_iterator<const T*> >();
67     test3<T, Iter1, forward_iterator<const T*> >();
68     test3<T, Iter1, bidirectional_iterator<const T*> >();
69     test3<T, Iter1, random_access_iterator<const T*> >();
70     test3<T, Iter1, const T*>();
71 }
72 
73 template<class T>
test1()74 TEST_CONSTEXPR_CXX20 void test1()
75 {
76     test2<T, cpp17_input_iterator<const T*> >();
77     test2<T, forward_iterator<const T*> >();
78     test2<T, bidirectional_iterator<const T*> >();
79     test2<T, random_access_iterator<const T*> >();
80     test2<T, const T*>();
81 }
82 
test()83 TEST_CONSTEXPR_CXX20 bool test()
84 {
85     test1<TrivialSortableWithComp>();
86     test1<NonTrivialSortableWithComp>();
87     return true;
88 }
89 
main(int,char **)90 int main(int, char**)
91 {
92     test();
93 #if TEST_STD_VER > 17
94     static_assert(test());
95 #endif
96 
97     return 0;
98 }
99