libcxx/test/std/algorithms/alg.modifying.operations/alg.rotate/rotate_copy.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<ForwardIterator InIter, OutputIterator<auto, InIter::reference> OutIter>
  12 //   constexpr OutIter          // constexpr after C++17
  13 //   rotate_copy(InIter first, InIter middle, InIter last, OutIter result);
  14
  15 #include <algorithm>
  16 #include <cassert>
  17
  18 #include "test_macros.h"
  19 #include "test_iterators.h"
  20
  21
  22 template <class InIter, class OutIter>
  23 TEST_CONSTEXPR_CXX20 void test() {
  24   int ia[] = {0, 1, 2, 3};
  25   const unsigned sa = sizeof(ia) / sizeof(ia[0]);
  26   int ib[sa] = {0};
  27
  28   OutIter r = std::rotate_copy(InIter(ia), InIter(ia), InIter(ia), OutIter(ib));
  29   assert(base(r) == ib);
  30
  31   r = std::rotate_copy(InIter(ia), InIter(ia), InIter(ia + 1), OutIter(ib));
  32   assert(base(r) == ib + 1);
  33   assert(ib[0] == 0);
  34
  35   r = std::rotate_copy(InIter(ia), InIter(ia + 1), InIter(ia + 1), OutIter(ib));
  36   assert(base(r) == ib + 1);
  37   assert(ib[0] == 0);
  38
  39   r = std::rotate_copy(InIter(ia), InIter(ia), InIter(ia + 2), OutIter(ib));
  40   assert(base(r) == ib + 2);
  41   assert(ib[0] == 0);
  42   assert(ib[1] == 1);
  43
  44   r = std::rotate_copy(InIter(ia), InIter(ia + 1), InIter(ia + 2), OutIter(ib));
  45   assert(base(r) == ib + 2);
  46   assert(ib[0] == 1);
  47   assert(ib[1] == 0);
  48
  49   r = std::rotate_copy(InIter(ia), InIter(ia + 2), InIter(ia + 2), OutIter(ib));
  50   assert(base(r) == ib + 2);
  51   assert(ib[0] == 0);
  52   assert(ib[1] == 1);
  53
  54   r = std::rotate_copy(InIter(ia), InIter(ia), InIter(ia + 3), OutIter(ib));
  55   assert(base(r) == ib + 3);
  56   assert(ib[0] == 0);
  57   assert(ib[1] == 1);
  58   assert(ib[2] == 2);
  59
  60   r = std::rotate_copy(InIter(ia), InIter(ia + 1), InIter(ia + 3), OutIter(ib));
  61   assert(base(r) == ib + 3);
  62   assert(ib[0] == 1);
  63   assert(ib[1] == 2);
  64   assert(ib[2] == 0);
  65
  66   r = std::rotate_copy(InIter(ia), InIter(ia + 2), InIter(ia + 3), OutIter(ib));
  67   assert(base(r) == ib + 3);
  68   assert(ib[0] == 2);
  69   assert(ib[1] == 0);
  70   assert(ib[2] == 1);
  71
  72   r = std::rotate_copy(InIter(ia), InIter(ia + 3), InIter(ia + 3), OutIter(ib));
  73   assert(base(r) == ib + 3);
  74   assert(ib[0] == 0);
  75   assert(ib[1] == 1);
  76   assert(ib[2] == 2);
  77
  78   r = std::rotate_copy(InIter(ia), InIter(ia), InIter(ia + 4), OutIter(ib));
  79   assert(base(r) == ib + 4);
  80   assert(ib[0] == 0);
  81   assert(ib[1] == 1);
  82   assert(ib[2] == 2);
  83   assert(ib[3] == 3);
  84
  85   r = std::rotate_copy(InIter(ia), InIter(ia + 1), InIter(ia + 4), OutIter(ib));
  86   assert(base(r) == ib + 4);
  87   assert(ib[0] == 1);
  88   assert(ib[1] == 2);
  89   assert(ib[2] == 3);
  90   assert(ib[3] == 0);
  91
  92   r = std::rotate_copy(InIter(ia), InIter(ia + 2), InIter(ia + 4), OutIter(ib));
  93   assert(base(r) == ib + 4);
  94   assert(ib[0] == 2);
  95   assert(ib[1] == 3);
  96   assert(ib[2] == 0);
  97   assert(ib[3] == 1);
  98
  99   r = std::rotate_copy(InIter(ia), InIter(ia + 3), InIter(ia + 4), OutIter(ib));
 100   assert(base(r) == ib + 4);
 101   assert(ib[0] == 3);
 102   assert(ib[1] == 0);
 103   assert(ib[2] == 1);
 104   assert(ib[3] == 2);
 105
 106   r = std::rotate_copy(InIter(ia), InIter(ia + 4), InIter(ia + 4), OutIter(ib));
 107   assert(base(r) == ib + 4);
 108   assert(ib[0] == 0);
 109   assert(ib[1] == 1);
 110   assert(ib[2] == 2);
 111   assert(ib[3] == 3);
 112
 113   {
 114     int ints[] = {1, 3, 5, 2, 5, 6};
 115     int const n_ints = sizeof(ints)/sizeof(int);
 116     int zeros[n_ints] = {0};
 117
 118     const std::size_t N = 2;
 119     const auto middle = std::begin(ints) + N;
 120     auto it = std::rotate_copy(std::begin(ints), middle, std::end(ints), std::begin(zeros));
 121     assert(std::distance(std::begin(zeros), it) == n_ints);
 122     assert(std::equal(std::begin(ints), middle, std::begin(zeros) + n_ints - N));
 123     assert(std::equal(middle, std::end(ints), std::begin(zeros)));
 124   }
 125 }
 126
 127 TEST_CONSTEXPR_CXX20 bool all_tests() {
 128   test<bidirectional_iterator<const int*>, cpp17_output_iterator<int*> >();
 129   test<bidirectional_iterator<const int*>, forward_iterator<int*> >();
 130   test<bidirectional_iterator<const int*>, bidirectional_iterator<int*> >();
 131   test<bidirectional_iterator<const int*>, random_access_iterator<int*> >();
 132   test<bidirectional_iterator<const int*>, int*>();
 133
 134   test<random_access_iterator<const int*>, cpp17_output_iterator<int*> >();
 135   test<random_access_iterator<const int*>, forward_iterator<int*> >();
 136   test<random_access_iterator<const int*>, bidirectional_iterator<int*> >();
 137   test<random_access_iterator<const int*>, random_access_iterator<int*> >();
 138   test<random_access_iterator<const int*>, int*>();
 139
 140   test<const int*, cpp17_output_iterator<int*> >();
 141   test<const int*, forward_iterator<int*> >();
 142   test<const int*, bidirectional_iterator<int*> >();
 143   test<const int*, random_access_iterator<int*> >();
 144   test<const int*, int*>();
 145
 146   return true;
 147 }
 148
 149 int main(int, char**) {
 150   all_tests();
 151
 152 #if TEST_STD_VER > 17
 153   static_assert(all_tests());
 154 #endif
 155   return 0;
 156 }