libcxx/test/std/algorithms/alg.nonmodifying/alg.equal/equal_pred.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 // template<InputIterator Iter1, InputIterator Iter2,
  12 //          Predicate<auto, Iter1::value_type, Iter2::value_type> Pred>
  13 //   requires CopyConstructible<Pred>
  14 //   constexpr bool     // constexpr after c++17
  15 //   equal(Iter1 first1, Iter1 last1, Iter2 first2, Pred pred);
  16 //
  17 // Introduced in C++14:
  18 // template<InputIterator Iter1, InputIterator Iter2,
  19 //          Predicate<auto, Iter1::value_type, Iter2::value_type> Pred>
  20 //   requires CopyConstructible<Pred>
  21 //   constexpr bool     // constexpr after c++17
  22 //   equal(Iter1 first1, Iter1 last1, Iter2 first2, Iter2 last2, Pred pred);
  23
  24
  25 #include <algorithm>
  26 #include <functional>
  27 #include <cassert>
  28
  29 #include "test_macros.h"
  30 #include "test_iterators.h"
  31
  32 #if TEST_STD_VER > 17
  33 TEST_CONSTEXPR bool eq(int a, int b) { return a == b; }
  34
  35 TEST_CONSTEXPR bool test_constexpr() {
  36     int ia[] = {1, 3, 6, 7};
  37     int ib[] = {1, 3};
  38     int ic[] = {1, 3, 5, 7};
  39     typedef input_iterator<int*>         II;
  40     typedef bidirectional_iterator<int*> BI;
  41
  42     return !std::equal(std::begin(ia), std::end(ia), std::begin(ic)              , eq)
  43         && !std::equal(std::begin(ia), std::end(ia), std::begin(ic), std::end(ic), eq)
  44         &&  std::equal(std::begin(ib), std::end(ib), std::begin(ic)              , eq)
  45         && !std::equal(std::begin(ib), std::end(ib), std::begin(ic), std::end(ic), eq)
  46
  47         &&  std::equal(II(std::begin(ib)), II(std::end(ib)), II(std::begin(ic))                  , eq)
  48         && !std::equal(BI(std::begin(ib)), BI(std::end(ib)), BI(std::begin(ic)), BI(std::end(ic)), eq)
  49         ;
  50     }
  51 #endif
  52
  53
  54 int comparison_count = 0;
  55 template <typename T>
  56 bool counting_equals ( const T &a, const T &b ) {
  57     ++comparison_count;
  58     return a == b;
  59 }
  60
  61 int main(int, char**)
  62 {
  63     int ia[] = {0, 1, 2, 3, 4, 5};
  64     const unsigned s = sizeof(ia)/sizeof(ia[0]);
  65     int ib[s] = {0, 1, 2, 5, 4, 5};
  66     assert(std::equal(input_iterator<const int*>(ia),
  67                       input_iterator<const int*>(ia+s),
  68                       input_iterator<const int*>(ia),
  69                       std::equal_to<int>()));
  70 #if TEST_STD_VER >= 14
  71     assert(std::equal(input_iterator<const int*>(ia),
  72                       input_iterator<const int*>(ia+s),
  73                       input_iterator<const int*>(ia),
  74                       input_iterator<const int*>(ia+s),
  75                       std::equal_to<int>()));
  76     assert(std::equal(random_access_iterator<const int*>(ia),
  77                       random_access_iterator<const int*>(ia+s),
  78                       random_access_iterator<const int*>(ia),
  79                       random_access_iterator<const int*>(ia+s),
  80                       std::equal_to<int>()));
  81
  82     comparison_count = 0;
  83     assert(!std::equal(input_iterator<const int*>(ia),
  84                       input_iterator<const int*>(ia+s),
  85                       input_iterator<const int*>(ia),
  86                       input_iterator<const int*>(ia+s-1),
  87                       counting_equals<int>));
  88     assert(comparison_count > 0);
  89     comparison_count = 0;
  90     assert(!std::equal(random_access_iterator<const int*>(ia),
  91                       random_access_iterator<const int*>(ia+s),
  92                       random_access_iterator<const int*>(ia),
  93                       random_access_iterator<const int*>(ia+s-1),
  94                       counting_equals<int>));
  95     assert(comparison_count == 0);
  96 #endif
  97     assert(!std::equal(input_iterator<const int*>(ia),
  98                        input_iterator<const int*>(ia+s),
  99                        input_iterator<const int*>(ib),
 100                        std::equal_to<int>()));
 101 #if TEST_STD_VER >= 14
 102     assert(!std::equal(input_iterator<const int*>(ia),
 103                        input_iterator<const int*>(ia+s),
 104                        input_iterator<const int*>(ib),
 105                        input_iterator<const int*>(ib+s),
 106                        std::equal_to<int>()));
 107     assert(!std::equal(random_access_iterator<const int*>(ia),
 108                        random_access_iterator<const int*>(ia+s),
 109                        random_access_iterator<const int*>(ib),
 110                        random_access_iterator<const int*>(ib+s),
 111                        std::equal_to<int>()));
 112 #endif
 113
 114 #if TEST_STD_VER > 17
 115     static_assert(test_constexpr());
 116 #endif
 117
 118   return 0;
 119 }