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<ForwardIterator Iter1, ForwardIterator Iter2,
12 // Predicate<auto, Iter1::value_type, Iter2::value_type> Pred>
13 // requires CopyConstructible<Pred>
14 // constexpr Iter1 // constexpr after C++17
15 // find_end(Iter1 first1, Iter1 last1, Iter2 first2, Iter2 last2, Pred pred);
16
17 #include <algorithm>
18 #include <functional>
19 #include <cassert>
20
21 #include "test_macros.h"
22 #include "test_iterators.h"
23
24 struct count_equal
25 {
26 static unsigned count;
27 template <class T>
operator ()count_equal28 TEST_CONSTEXPR_CXX14 bool operator()(const T& x, const T& y)
29 {++count; return x == y;}
30 };
31
32 #if TEST_STD_VER > 17
test_constexpr()33 constexpr bool test_constexpr() {
34 int ia[] = {0, 1, 2};
35 int ib[] = {4, 5, 6};
36 int ic[] = {0, 1, 2, 3, 4, 5, 0, 1, 2, 3, 4, 0, 1, 2, 3, 0, 1, 2, 0, 1, 0};
37 typedef forward_iterator<int*> FI;
38 typedef bidirectional_iterator<int*> BI;
39 typedef random_access_iterator<int*> RI;
40 std::equal_to<int> eq{};
41 return (std::find_end(FI(std::begin(ic)), FI(std::end(ic)), FI(std::begin(ia)), FI(std::end(ia)), eq) == FI(ic+15))
42 && (std::find_end(FI(std::begin(ic)), FI(std::end(ic)), FI(std::begin(ib)), FI(std::end(ib)), eq) == FI(std::end(ic)))
43 && (std::find_end(BI(std::begin(ic)), BI(std::end(ic)), BI(std::begin(ia)), BI(std::end(ia)), eq) == BI(ic+15))
44 && (std::find_end(BI(std::begin(ic)), BI(std::end(ic)), BI(std::begin(ib)), BI(std::end(ib)), eq) == BI(std::end(ic)))
45 && (std::find_end(RI(std::begin(ic)), RI(std::end(ic)), RI(std::begin(ia)), RI(std::end(ia)), eq) == RI(ic+15))
46 && (std::find_end(RI(std::begin(ic)), RI(std::end(ic)), RI(std::begin(ib)), RI(std::end(ib)), eq) == RI(std::end(ic)))
47 ;
48 }
49 #endif
50
51 unsigned count_equal::count = 0;
52
53 template <class Iter1, class Iter2>
54 void
test()55 test()
56 {
57 int ia[] = {0, 1, 2, 3, 4, 5, 0, 1, 2, 3, 4, 0, 1, 2, 3, 0, 1, 2, 0, 1, 0};
58 const unsigned sa = sizeof(ia)/sizeof(ia[0]);
59 int b[] = {0};
60 count_equal::count = 0;
61 assert(std::find_end(Iter1(ia), Iter1(ia+sa), Iter2(b), Iter2(b+1), count_equal()) == Iter1(ia+sa-1));
62 assert(count_equal::count <= 1*(sa-1+1));
63 int c[] = {0, 1};
64 count_equal::count = 0;
65 assert(std::find_end(Iter1(ia), Iter1(ia+sa), Iter2(c), Iter2(c+2), count_equal()) == Iter1(ia+18));
66 assert(count_equal::count <= 2*(sa-2+1));
67 int d[] = {0, 1, 2};
68 count_equal::count = 0;
69 assert(std::find_end(Iter1(ia), Iter1(ia+sa), Iter2(d), Iter2(d+3), count_equal()) == Iter1(ia+15));
70 assert(count_equal::count <= 3*(sa-3+1));
71 int e[] = {0, 1, 2, 3};
72 count_equal::count = 0;
73 assert(std::find_end(Iter1(ia), Iter1(ia+sa), Iter2(e), Iter2(e+4), count_equal()) == Iter1(ia+11));
74 assert(count_equal::count <= 4*(sa-4+1));
75 int f[] = {0, 1, 2, 3, 4};
76 count_equal::count = 0;
77 assert(std::find_end(Iter1(ia), Iter1(ia+sa), Iter2(f), Iter2(f+5), count_equal()) == Iter1(ia+6));
78 assert(count_equal::count <= 5*(sa-5+1));
79 int g[] = {0, 1, 2, 3, 4, 5};
80 count_equal::count = 0;
81 assert(std::find_end(Iter1(ia), Iter1(ia+sa), Iter2(g), Iter2(g+6), count_equal()) == Iter1(ia));
82 assert(count_equal::count <= 6*(sa-6+1));
83 int h[] = {0, 1, 2, 3, 4, 5, 6};
84 count_equal::count = 0;
85 assert(std::find_end(Iter1(ia), Iter1(ia+sa), Iter2(h), Iter2(h+7), count_equal()) == Iter1(ia+sa));
86 assert(count_equal::count <= 7*(sa-7+1));
87 count_equal::count = 0;
88 assert(std::find_end(Iter1(ia), Iter1(ia+sa), Iter2(b), Iter2(b), count_equal()) == Iter1(ia+sa));
89 assert(count_equal::count <= 0);
90 count_equal::count = 0;
91 assert(std::find_end(Iter1(ia), Iter1(ia), Iter2(b), Iter2(b+1), count_equal()) == Iter1(ia));
92 assert(count_equal::count <= 0);
93 }
94
main(int,char **)95 int main(int, char**)
96 {
97 test<forward_iterator<const int*>, forward_iterator<const int*> >();
98 test<forward_iterator<const int*>, bidirectional_iterator<const int*> >();
99 test<forward_iterator<const int*>, random_access_iterator<const int*> >();
100 test<bidirectional_iterator<const int*>, forward_iterator<const int*> >();
101 test<bidirectional_iterator<const int*>, bidirectional_iterator<const int*> >();
102 test<bidirectional_iterator<const int*>, random_access_iterator<const int*> >();
103 test<random_access_iterator<const int*>, forward_iterator<const int*> >();
104 test<random_access_iterator<const int*>, bidirectional_iterator<const int*> >();
105 test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
106
107 #if TEST_STD_VER > 17
108 static_assert(test_constexpr());
109 #endif
110
111 return 0;
112 }
113