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 // <numeric>
10
11 // Became constexpr in C++20
12 // template <InputIterator Iter1, InputIterator Iter2, MoveConstructible T,
13 // class BinaryOperation1,
14 // Callable<auto, Iter1::reference, Iter2::reference> BinaryOperation2>
15 // requires Callable<BinaryOperation1, const T&, BinaryOperation2::result_type>
16 // && HasAssign<T, BinaryOperation1::result_type>
17 // && CopyConstructible<BinaryOperation1>
18 // && CopyConstructible<BinaryOperation2>
19 // T
20 // inner_product(Iter1 first1, Iter1 last1, Iter2 first2,
21 // T init, BinaryOperation1 binary_op1, BinaryOperation2 binary_op2);
22
23 #include <numeric>
24 #include <functional>
25 #include <string>
26 #include <cassert>
27
28 #include "test_macros.h"
29 #include "test_iterators.h"
30
31 #if TEST_STD_VER > 17
32 struct do_nothing_op
33 {
34 template<class T>
operator ()do_nothing_op35 constexpr T operator()(T a, T)
36 { return a; }
37 };
38
39 struct rvalue_addable
40 {
41 bool correctOperatorUsed = false;
42
operator *rvalue_addable43 constexpr rvalue_addable operator*(rvalue_addable const&) { return *this; }
44
45 // make sure the predicate is passed an rvalue and an lvalue (so check that the first argument was moved)
operator ()rvalue_addable46 constexpr rvalue_addable operator()(rvalue_addable&& r, rvalue_addable const&) {
47 r.correctOperatorUsed = true;
48 return std::move(r);
49 }
50 };
51
operator +(rvalue_addable & lhs,rvalue_addable const &)52 constexpr rvalue_addable operator+(rvalue_addable& lhs, rvalue_addable const&)
53 {
54 lhs.correctOperatorUsed = false;
55 return lhs;
56 }
57
operator +(rvalue_addable && lhs,rvalue_addable const &)58 constexpr rvalue_addable operator+(rvalue_addable&& lhs, rvalue_addable const&)
59 {
60 lhs.correctOperatorUsed = true;
61 return std::move(lhs);
62 }
63
64 constexpr void
test_use_move()65 test_use_move()
66 {
67 rvalue_addable arr[100];
68 auto res1 = std::inner_product(arr, arr + 100, arr, rvalue_addable());
69 auto res2 = std::inner_product(arr, arr + 100, arr, rvalue_addable(), /*predicate=*/rvalue_addable(), do_nothing_op());
70
71 assert(res1.correctOperatorUsed);
72 assert(res2.correctOperatorUsed);
73 }
74 #endif // TEST_STD_VER > 17
75
test_string()76 TEST_CONSTEXPR_CXX20 void test_string() {
77 std::string sa[] = {"a", "b", "c"};
78 assert(std::accumulate(sa, sa + 3, std::string()) == "abc");
79 assert(std::accumulate(sa, sa + 3, std::string(), std::plus<std::string>()) == "abc");
80 }
81
82 template <class Iter1, class Iter2, class T>
83 TEST_CONSTEXPR_CXX20 void
test(Iter1 first1,Iter1 last1,Iter2 first2,T init,T x)84 test(Iter1 first1, Iter1 last1, Iter2 first2, T init, T x)
85 {
86 assert(std::inner_product(first1, last1, first2, init,
87 std::multiplies<int>(), std::plus<int>()) == x);
88 }
89
90 template <class Iter1, class Iter2>
91 TEST_CONSTEXPR_CXX20 void
test()92 test()
93 {
94 int a[] = {1, 2, 3, 4, 5, 6};
95 int b[] = {6, 5, 4, 3, 2, 1};
96 unsigned sa = sizeof(a) / sizeof(a[0]);
97 test(Iter1(a), Iter1(a), Iter2(b), 1, 1);
98 test(Iter1(a), Iter1(a), Iter2(b), 10, 10);
99 test(Iter1(a), Iter1(a+1), Iter2(b), 1, 7);
100 test(Iter1(a), Iter1(a+1), Iter2(b), 10, 70);
101 test(Iter1(a), Iter1(a+2), Iter2(b), 1, 49);
102 test(Iter1(a), Iter1(a+2), Iter2(b), 10, 490);
103 test(Iter1(a), Iter1(a+sa), Iter2(b), 1, 117649);
104 test(Iter1(a), Iter1(a+sa), Iter2(b), 10, 1176490);
105 }
106
107 TEST_CONSTEXPR_CXX20 bool
test()108 test()
109 {
110 test<cpp17_input_iterator<const int*>, cpp17_input_iterator<const int*> >();
111 test<cpp17_input_iterator<const int*>, forward_iterator<const int*> >();
112 test<cpp17_input_iterator<const int*>, bidirectional_iterator<const int*> >();
113 test<cpp17_input_iterator<const int*>, random_access_iterator<const int*> >();
114 test<cpp17_input_iterator<const int*>, const int*>();
115
116 test<forward_iterator<const int*>, cpp17_input_iterator<const int*> >();
117 test<forward_iterator<const int*>, forward_iterator<const int*> >();
118 test<forward_iterator<const int*>, bidirectional_iterator<const int*> >();
119 test<forward_iterator<const int*>, random_access_iterator<const int*> >();
120 test<forward_iterator<const int*>, const int*>();
121
122 test<bidirectional_iterator<const int*>, cpp17_input_iterator<const int*> >();
123 test<bidirectional_iterator<const int*>, forward_iterator<const int*> >();
124 test<bidirectional_iterator<const int*>, bidirectional_iterator<const int*> >();
125 test<bidirectional_iterator<const int*>, random_access_iterator<const int*> >();
126 test<bidirectional_iterator<const int*>, const int*>();
127
128 test<random_access_iterator<const int*>, cpp17_input_iterator<const int*> >();
129 test<random_access_iterator<const int*>, forward_iterator<const int*> >();
130 test<random_access_iterator<const int*>, bidirectional_iterator<const int*> >();
131 test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
132 test<random_access_iterator<const int*>, const int*>();
133
134 test<const int*, cpp17_input_iterator<const int*> >();
135 test<const int*, forward_iterator<const int*> >();
136 test<const int*, bidirectional_iterator<const int*> >();
137 test<const int*, random_access_iterator<const int*> >();
138 test<const int*, const int*>();
139
140 #if TEST_STD_VER > 17
141 test_use_move();
142 #endif // TEST_STD_VER > 17
143
144 test_string();
145
146 return true;
147 }
148
main(int,char **)149 int main(int, char**)
150 {
151 test();
152 #if TEST_STD_VER > 17
153 static_assert(test());
154 #endif
155 return 0;
156 }
157