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