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<class ForwardIterator, class Size, class T, class BinaryPredicate> 12 // constexpr ForwardIterator // constexpr after C++17 13 // search_n(ForwardIterator first, ForwardIterator last, Size count, 14 // const T& value, BinaryPredicate pred); 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 #if TEST_STD_VER > 17 24 TEST_CONSTEXPR bool eq(int a, int b) { return a == b; } 25 26 TEST_CONSTEXPR bool test_constexpr() { 27 int ia[] = {0, 0, 1, 1, 2, 2}; 28 return (std::search_n(std::begin(ia), std::end(ia), 1, 0, eq) == ia) 29 && (std::search_n(std::begin(ia), std::end(ia), 2, 1, eq) == ia+2) 30 && (std::search_n(std::begin(ia), std::end(ia), 1, 3, eq) == std::end(ia)) 31 ; 32 } 33 #endif 34 35 struct count_equal { 36 static unsigned count; 37 template <class T> 38 bool operator()(const T& x, const T& y) const { 39 ++count; 40 return x == y; 41 } 42 }; 43 44 unsigned count_equal::count = 0; 45 46 47 template <class Iter> 48 void 49 test() 50 { 51 int ia[] = {0, 1, 2, 3, 4, 5}; 52 const unsigned sa = sizeof(ia)/sizeof(ia[0]); 53 count_equal::count = 0; 54 assert(std::search_n(Iter(ia), Iter(ia+sa), 0, 0, count_equal()) == Iter(ia)); 55 assert(count_equal::count <= sa); 56 count_equal::count = 0; 57 assert(std::search_n(Iter(ia), Iter(ia+sa), 1, 0, count_equal()) == Iter(ia+0)); 58 assert(count_equal::count <= sa); 59 count_equal::count = 0; 60 assert(std::search_n(Iter(ia), Iter(ia+sa), 2, 0, count_equal()) == Iter(ia+sa)); 61 assert(count_equal::count <= sa); 62 count_equal::count = 0; 63 assert(std::search_n(Iter(ia), Iter(ia+sa), sa, 0, count_equal()) == Iter(ia+sa)); 64 assert(count_equal::count <= sa); 65 count_equal::count = 0; 66 assert(std::search_n(Iter(ia), Iter(ia+sa), 0, 3, count_equal()) == Iter(ia)); 67 assert(count_equal::count <= sa); 68 count_equal::count = 0; 69 assert(std::search_n(Iter(ia), Iter(ia+sa), 1, 3, count_equal()) == Iter(ia+3)); 70 assert(count_equal::count <= sa); 71 count_equal::count = 0; 72 assert(std::search_n(Iter(ia), Iter(ia+sa), 2, 3, count_equal()) == Iter(ia+sa)); 73 assert(count_equal::count <= sa); 74 count_equal::count = 0; 75 assert(std::search_n(Iter(ia), Iter(ia+sa), sa, 3, count_equal()) == Iter(ia+sa)); 76 assert(count_equal::count <= sa); 77 count_equal::count = 0; 78 assert(std::search_n(Iter(ia), Iter(ia+sa), 0, 5, count_equal()) == Iter(ia)); 79 assert(count_equal::count <= sa); 80 count_equal::count = 0; 81 assert(std::search_n(Iter(ia), Iter(ia+sa), 1, 5, count_equal()) == Iter(ia+5)); 82 assert(count_equal::count <= sa); 83 count_equal::count = 0; 84 assert(std::search_n(Iter(ia), Iter(ia+sa), 2, 5, count_equal()) == Iter(ia+sa)); 85 assert(count_equal::count <= sa); 86 count_equal::count = 0; 87 assert(std::search_n(Iter(ia), Iter(ia+sa), sa, 5, count_equal()) == Iter(ia+sa)); 88 assert(count_equal::count <= sa); 89 count_equal::count = 0; 90 91 int ib[] = {0, 0, 1, 1, 2, 2}; 92 const unsigned sb = sizeof(ib)/sizeof(ib[0]); 93 assert(std::search_n(Iter(ib), Iter(ib+sb), 0, 0, count_equal()) == Iter(ib)); 94 assert(count_equal::count <= sb); 95 count_equal::count = 0; 96 assert(std::search_n(Iter(ib), Iter(ib+sb), 1, 0, count_equal()) == Iter(ib+0)); 97 assert(count_equal::count <= sb); 98 count_equal::count = 0; 99 assert(std::search_n(Iter(ib), Iter(ib+sb), 2, 0, count_equal()) == Iter(ib+0)); 100 assert(count_equal::count <= sb); 101 count_equal::count = 0; 102 assert(std::search_n(Iter(ib), Iter(ib+sb), 3, 0, count_equal()) == Iter(ib+sb)); 103 assert(count_equal::count <= sb); 104 count_equal::count = 0; 105 assert(std::search_n(Iter(ib), Iter(ib+sb), sb, 0, count_equal()) == Iter(ib+sb)); 106 assert(count_equal::count <= sb); 107 count_equal::count = 0; 108 assert(std::search_n(Iter(ib), Iter(ib+sb), 0, 1, count_equal()) == Iter(ib)); 109 assert(count_equal::count <= sb); 110 count_equal::count = 0; 111 assert(std::search_n(Iter(ib), Iter(ib+sb), 1, 1, count_equal()) == Iter(ib+2)); 112 assert(count_equal::count <= sb); 113 count_equal::count = 0; 114 assert(std::search_n(Iter(ib), Iter(ib+sb), 2, 1, count_equal()) == Iter(ib+2)); 115 assert(count_equal::count <= sb); 116 count_equal::count = 0; 117 assert(std::search_n(Iter(ib), Iter(ib+sb), 3, 1, count_equal()) == Iter(ib+sb)); 118 assert(count_equal::count <= sb); 119 count_equal::count = 0; 120 assert(std::search_n(Iter(ib), Iter(ib+sb), sb, 1, count_equal()) == Iter(ib+sb)); 121 assert(count_equal::count <= sb); 122 count_equal::count = 0; 123 assert(std::search_n(Iter(ib), Iter(ib+sb), 0, 2, count_equal()) == Iter(ib)); 124 assert(count_equal::count <= sb); 125 count_equal::count = 0; 126 assert(std::search_n(Iter(ib), Iter(ib+sb), 1, 2, count_equal()) == Iter(ib+4)); 127 assert(count_equal::count <= sb); 128 count_equal::count = 0; 129 assert(std::search_n(Iter(ib), Iter(ib+sb), 2, 2, count_equal()) == Iter(ib+4)); 130 assert(count_equal::count <= sb); 131 count_equal::count = 0; 132 assert(std::search_n(Iter(ib), Iter(ib+sb), 3, 2, count_equal()) == Iter(ib+sb)); 133 assert(count_equal::count <= sb); 134 count_equal::count = 0; 135 assert(std::search_n(Iter(ib), Iter(ib+sb), sb, 2, count_equal()) == Iter(ib+sb)); 136 assert(count_equal::count <= sb); 137 count_equal::count = 0; 138 139 int ic[] = {0, 0, 0}; 140 const unsigned sc = sizeof(ic)/sizeof(ic[0]); 141 assert(std::search_n(Iter(ic), Iter(ic+sc), 0, 0, count_equal()) == Iter(ic)); 142 assert(count_equal::count <= sc); 143 count_equal::count = 0; 144 assert(std::search_n(Iter(ic), Iter(ic+sc), 1, 0, count_equal()) == Iter(ic)); 145 assert(count_equal::count <= sc); 146 count_equal::count = 0; 147 assert(std::search_n(Iter(ic), Iter(ic+sc), 2, 0, count_equal()) == Iter(ic)); 148 assert(count_equal::count <= sc); 149 count_equal::count = 0; 150 assert(std::search_n(Iter(ic), Iter(ic+sc), 3, 0, count_equal()) == Iter(ic)); 151 assert(count_equal::count <= sc); 152 count_equal::count = 0; 153 assert(std::search_n(Iter(ic), Iter(ic+sc), 4, 0, count_equal()) == Iter(ic+sc)); 154 assert(count_equal::count <= sc); 155 count_equal::count = 0; 156 157 // Check that we properly convert the size argument to an integral. 158 TEST_IGNORE_NODISCARD std::search_n(Iter(ic), Iter(ic+sc), UserDefinedIntegral<unsigned>(4), 0, count_equal()); 159 count_equal::count = 0; 160 } 161 162 class A { 163 public: 164 A(int x, int y) : x_(x), y_(y) {} 165 int x() const { return x_; } 166 int y() const { return y_; } 167 168 private: 169 int x_; 170 int y_; 171 }; 172 173 struct Pred { 174 bool operator()(const A& l, int r) const { return l.x() == r; } 175 }; 176 177 int main(int, char**) 178 { 179 test<forward_iterator<const int*> >(); 180 test<bidirectional_iterator<const int*> >(); 181 test<random_access_iterator<const int*> >(); 182 183 // test bug reported in https://reviews.llvm.org/D124079?#3661721 184 { 185 A a[] = {A(1, 2), A(2, 3), A(2, 4)}; 186 int value = 2; 187 auto result = std::search_n(a, a + 3, 1, value, Pred()); 188 assert(result == a + 1); 189 } 190 191 #if TEST_STD_VER > 17 192 static_assert(test_constexpr()); 193 #endif 194 195 return 0; 196 } 197