libcxx/test/std/algorithms/alg.nonmodifying/alg.find.first.of/ranges.find_first_of.pass.cpp

   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 // UNSUPPORTED: c++03, c++11, c++14, c++17
  12
  13 // template<input_iterator I1, sentinel_for<I1> S1, forward_iterator I2, sentinel_for<I2> S2,
  14 //          class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
  15 //   requires indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
  16 //   constexpr I1 ranges::find_first_of(I1 first1, S1 last1, I2 first2, S2 last2,
  17 //                                      Pred pred = {},
  18 //                                      Proj1 proj1 = {}, Proj2 proj2 = {});
  19 // template<input_range R1, forward_range R2,
  20 //          class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
  21 //   requires indirectly_comparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
  22 //   constexpr borrowed_iterator_t<R1>
  23 //     ranges::find_first_of(R1&& r1, R2&& r2,
  24 //                           Pred pred = {},
  25 //                           Proj1 proj1 = {}, Proj2 proj2 = {});
  26
  27 #include <algorithm>
  28 #include <array>
  29 #include <functional>
  30 #include <ranges>
  31
  32 #include "almost_satisfies_types.h"
  33 #include "boolean_testable.h"
  34 #include "test_iterators.h"
  35
  36 template <class Iter1, class Iter2 = int*, class Sent1 = Iter1, class Sent2 = Iter2>
  37 concept HasFindFirstOfIt = requires(Iter1 iter1, Sent1 sent1, Iter2 iter2, Sent2 sent2) {
  38                              std::ranges::find_first_of(iter1, sent1, iter2, sent2);
  39                            };
  40
  41 static_assert(HasFindFirstOfIt<int*>);
  42 static_assert(!HasFindFirstOfIt<InputIteratorNotDerivedFrom>);
  43 static_assert(!HasFindFirstOfIt<InputIteratorNotIndirectlyReadable>);
  44 static_assert(!HasFindFirstOfIt<InputIteratorNotInputOrOutputIterator>);
  45 static_assert(!HasFindFirstOfIt<int*, ForwardIteratorNotDerivedFrom>);
  46 static_assert(!HasFindFirstOfIt<int*, ForwardIteratorNotIncrementable>);
  47 static_assert(!HasFindFirstOfIt<int*, int*, SentinelForNotSemiregular>);
  48 static_assert(!HasFindFirstOfIt<int*, int*, SentinelForNotWeaklyEqualityComparableWith>);
  49 static_assert(!HasFindFirstOfIt<int*, int*, int*, SentinelForNotSemiregular>);
  50 static_assert(!HasFindFirstOfIt<int*, int*, int*, SentinelForNotWeaklyEqualityComparableWith>);
  51 static_assert(!HasFindFirstOfIt<int*, int**>); // not indirectly_comparable
  52
  53 template <class Range1, class Range2 = UncheckedRange<int*>>
  54 concept HasFindFirstOfR = requires(Range1 range1, Range2 range2) {
  55                              std::ranges::find_first_of(range1, range2);
  56                            };
  57
  58 static_assert(HasFindFirstOfR<UncheckedRange<int*>>);
  59 static_assert(!HasFindFirstOfR<InputRangeNotDerivedFrom>);
  60 static_assert(!HasFindFirstOfR<InputRangeNotIndirectlyReadable>);
  61 static_assert(!HasFindFirstOfR<InputRangeNotInputOrOutputIterator>);
  62 static_assert(!HasFindFirstOfR<UncheckedRange<int*>, ForwardRangeNotDerivedFrom>);
  63 static_assert(!HasFindFirstOfR<UncheckedRange<int*>, ForwardRangeNotIncrementable>);
  64 static_assert(!HasFindFirstOfR<UncheckedRange<int*>, InputRangeNotSentinelSemiregular>);
  65 static_assert(!HasFindFirstOfR<UncheckedRange<int*>, InputRangeNotSentinelEqualityComparableWith>);
  66 static_assert(!HasFindFirstOfR<UncheckedRange<int*>, ForwardRangeNotSentinelSemiregular>);
  67 static_assert(!HasFindFirstOfR<UncheckedRange<int*>, ForwardRangeNotSentinelEqualityComparableWith>);
  68 static_assert(!HasFindFirstOfR<UncheckedRange<int*>, UncheckedRange<int**>>); // not indirectly_comparable
  69
  70 template <int N1, int N2>
  71 struct Data {
  72   std::array<int, N1> input1;
  73   std::array<int, N2> input2;
  74   std::ptrdiff_t expected;
  75 };
  76
  77 template <class Iter1, class Sent1, class Iter2, class Sent2, int N1, int N2>
  78 constexpr void test(Data<N1, N2> d) {
  79   {
  80     std::same_as<Iter1> decltype(auto) ret =
  81         std::ranges::find_first_of(Iter1(d.input1.data()), Sent1(Iter1(d.input1.data() + d.input1.size())),
  82                                    Iter2(d.input2.data()), Sent2(Iter2(d.input2.data() + d.input2.size())));
  83     assert(base(ret) == d.input1.data() + d.expected);
  84   }
  85   {
  86     auto range1 = std::ranges::subrange(Iter1(d.input1.data()), Sent1(Iter1(d.input1.data() + d.input1.size())));
  87     auto range2 = std::ranges::subrange(Iter2(d.input2.data()), Sent2(Iter2(d.input2.data() + d.input2.size())));
  88     std::same_as<Iter1> decltype(auto) ret = std::ranges::find_first_of(range1, range2);
  89     assert(base(ret) == d.input1.data() + d.expected);
  90   }
  91 }
  92
  93 template <class Iter1, class Sent1, class Iter2, class Sent2 = Iter2>
  94 constexpr void test_iterators() {
  95   // simple test
  96   test<Iter1, Sent1, Iter2, Sent2, 4, 2>({.input1 = {1, 2, 3, 4}, .input2 = {2, 3}, .expected = 1});
  97   // other elements from input2 are checked
  98   test<Iter1, Sent1, Iter2, Sent2, 4, 2>({.input1 = {1, 2, 3, 4}, .input2 = {3, 2}, .expected = 1});
  99   // an empty second range returns last
 100   test<Iter1, Sent1, Iter2, Sent2, 4, 0>({.input1 = {1, 2, 3, 4}, .input2 = {}, .expected = 4});
 101   // check that an empty first range works
 102   test<Iter1, Sent1, Iter2, Sent2, 0, 1>({.input1 = {}, .input2 = {1}, .expected = 0});
 103   // check both ranges empty works
 104   test<Iter1, Sent1, Iter2, Sent2, 0, 0>({.input1 = {}, .input2 = {}, .expected = 0});
 105   // the first element is checked properly
 106   test<Iter1, Sent1, Iter2, Sent2, 5, 2>({.input1 = {5, 4, 3, 2, 1}, .input2 = {1, 5}, .expected = 0});
 107   // the last element is checked properly
 108   test<Iter1, Sent1, Iter2, Sent2, 5, 2>({.input1 = {5, 4, 3, 2, 1}, .input2 = {1, 6}, .expected = 4});
 109   // no match, one-past-the-end iterator should be returned
 110   test<Iter1, Sent1, Iter2, Sent2, 4, 4>({.input1 = {1, 3, 5, 7}, .input2 = {0, 2, 4, 6}, .expected = 4});
 111   // input2 contains a single element
 112   test<Iter1, Sent1, Iter2, Sent2, 4, 1>({.input1 = {1, 3, 5, 7}, .input2 = {1}, .expected = 0});
 113 }
 114
 115 template <class Iter1, class Sent1 = Iter1>
 116 constexpr void test_iterators1() {
 117   test_iterators<Iter1, Sent1, forward_iterator<int*>, sentinel_wrapper<forward_iterator<int*>>>();
 118   test_iterators<Iter1, Sent1, forward_iterator<int*>>();
 119   test_iterators<Iter1, Sent1, bidirectional_iterator<int*>>();
 120   test_iterators<Iter1, Sent1, random_access_iterator<int*>>();
 121   test_iterators<Iter1, Sent1, contiguous_iterator<int*>>();
 122   test_iterators<Iter1, Sent1, int*>();
 123 }
 124
 125 constexpr bool test() {
 126   test_iterators1<cpp20_input_iterator<int*>, sentinel_wrapper<cpp20_input_iterator<int*>>>();
 127   test_iterators1<cpp17_input_iterator<int*>, sentinel_wrapper<cpp17_input_iterator<int*>>>();
 128   test_iterators1<forward_iterator<int*>>();
 129   test_iterators1<bidirectional_iterator<int*>>();
 130   test_iterators1<random_access_iterator<int*>>();
 131   test_iterators1<contiguous_iterator<int*>>();
 132   test_iterators1<int*>();
 133
 134   { // check that std::ranges::dangling is returned
 135     [[maybe_unused]] std::same_as<std::ranges::dangling> decltype(auto) ret =
 136         std::ranges::find_first_of(std::array {1}, std::array {1});
 137   }
 138
 139   { // check that the predicate is used
 140     int a[] = {1, 2, 3, 4};
 141     int b[] = {2};
 142     {
 143       auto ret = std::ranges::find_first_of(std::begin(a), std::end(a),
 144                                             std::begin(b), std::end(b),
 145                                             std::ranges::greater{});
 146       assert(ret == a + 2);
 147     }
 148     {
 149       auto ret = std::ranges::find_first_of(a, b, std::ranges::greater{});
 150       assert(ret == a + 2);
 151     }
 152   }
 153
 154   { // check that the projections are used
 155     int a[] = {1, 2, 3, 4};
 156     int b[] = {4};
 157     {
 158       auto ret = std::ranges::find_first_of(std::begin(a), std::end(a),
 159                                             std::begin(b), std::end(b), {},
 160                                             [](int i) { return i / 2; },
 161                                             [](int i) { return i - 3; });
 162       assert(ret == a + 1);
 163     }
 164     {
 165       auto ret = std::ranges::find_first_of(a, b, {}, [](int i) { return i / 2; }, [](int i) { return i - 3; });
 166       assert(ret == a + 1);
 167     }
 168   }
 169
 170   { // check that std::invoke is used
 171     struct S1 {
 172       constexpr S1(int i_) : i(i_) {}
 173       constexpr bool compare(int j) const { return j == i; }
 174       constexpr const S1& identity() const { return *this; }
 175       int i;
 176     };
 177     struct S2 {
 178       constexpr S2(int i_) : i(i_) {}
 179       int i;
 180     };
 181
 182     {
 183       S1 a[] = {1, 2, 3, 4};
 184       S2 b[] = {2, 3};
 185       auto ret = std::ranges::find_first_of(std::begin(a), std::end(a),
 186                                             std::begin(b), std::end(b), &S1::compare, &S1::identity, &S2::i);
 187       assert(ret == a + 1);
 188     }
 189     {
 190       S1 a[] = {1, 2, 3, 4};
 191       S2 b[] = {2, 3};
 192       auto ret = std::ranges::find_first_of(a, b, &S1::compare, &S1::identity, &S2::i);
 193       assert(ret == a + 1);
 194     }
 195   }
 196
 197   { // check that the implicit conversion to bool works
 198     StrictComparable<int> a[] = {1, 2, 3, 4};
 199     StrictComparable<int> b[] = {2, 3};
 200     {
 201       auto ret = std::ranges::find_first_of(a, std::end(a), b, std::end(b));
 202       assert(ret == a + 1);
 203     }
 204     {
 205       auto ret = std::ranges::find_first_of(a, b);
 206       assert(ret == a + 1);
 207     }
 208   }
 209
 210   { // check that the complexity requirements are met
 211     int a[] = {1, 2, 3, 4};
 212     int b[] = {2, 3};
 213     {
 214       int predCount = 0;
 215       auto predCounter = [&](int, int) { ++predCount; return false; };
 216       int proj1Count = 0;
 217       auto proj1Counter = [&](int i) { ++proj1Count; return i; };
 218       int proj2Count = 0;
 219       auto proj2Counter = [&](int i) { ++proj2Count; return i; };
 220       auto ret = std::ranges::find_first_of(std::begin(a), std::end(a),
 221                                             std::begin(b), std::end(b), predCounter, proj1Counter, proj2Counter);
 222       assert(ret == a + 4);
 223       assert(predCount <= 8);
 224       assert(proj1Count <= 8);
 225       assert(proj2Count <= 8);
 226     }
 227     {
 228       int predCount = 0;
 229       auto predCounter = [&](int, int) { ++predCount; return false; };
 230       int proj1Count = 0;
 231       auto proj1Counter = [&](int i) { ++proj1Count; return i; };
 232       int proj2Count = 0;
 233       auto proj2Counter = [&](int i) { ++proj2Count; return i; };
 234       auto ret = std::ranges::find_first_of(a, b, predCounter, proj1Counter, proj2Counter);
 235       assert(ret == a + 4);
 236       assert(predCount == 8);
 237       assert(proj1Count == 8);
 238       assert(proj2Count == 8);
 239     }
 240   }
 241
 242   return true;
 243 }
 244
 245 int main(int, char**) {
 246   test();
 247   static_assert(test());
 248
 249   return 0;
 250 }