libcxx/test/std/containers/sequences/vector/reverse_iterators.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 // <vector>
  10
  11 // reverse_iterator       rbegin();
  12 // reverse_iterator       rend();
  13 // const_reverse_iterator rbegin()  const;
  14 // const_reverse_iterator rend()    const;
  15 // const_reverse_iterator crbegin() const;
  16 // const_reverse_iterator crend()   const;
  17
  18 #include <vector>
  19 #include <cassert>
  20 #include <iterator>
  21
  22 #include "min_allocator.h"
  23
  24 template <class Vector>
  25 TEST_CONSTEXPR_CXX20 void check_vector_reverse_iterators() {
  26     {
  27         Vector vec;
  28         assert(vec.rbegin() == vec.rend());
  29         assert(vec.crbegin() == vec.crend());
  30     }
  31     {
  32         const int n = 10;
  33         Vector vec;
  34         const Vector& cvec = vec;
  35         vec.reserve(n);
  36         for (int i = 0; i < n; ++i)
  37             vec.push_back(i);
  38         {
  39             int iterations = 0;
  40
  41             for (typename Vector::const_reverse_iterator it = vec.crbegin(); it != vec.crend(); ++it) {
  42                 assert(*it == (n - iterations - 1));
  43                 ++iterations;
  44             }
  45             assert(iterations == n);
  46         }
  47         {
  48             assert(cvec.rbegin() == vec.crbegin());
  49             assert(cvec.rend() == vec.crend());
  50         }
  51         {
  52             int iterations = 0;
  53
  54             for (typename Vector::reverse_iterator it = vec.rbegin(); it != vec.rend(); ++it) {
  55                 assert(*it == (n - iterations - 1));
  56                 *it = 40;
  57                 assert(*it == 40);
  58                 ++iterations;
  59             }
  60             assert(iterations == n);
  61         }
  62
  63         assert(std::distance(vec.rbegin(), vec.rend()) == n);
  64         assert(std::distance(cvec.rbegin(), cvec.rend()) == n);
  65         assert(std::distance(vec.crbegin(), vec.crend()) == n);
  66         assert(std::distance(cvec.crbegin(), cvec.crend()) == n);
  67     }
  68 }
  69
  70 TEST_CONSTEXPR_CXX20 bool test() {
  71     check_vector_reverse_iterators<std::vector<int> >();
  72 #if TEST_STD_VER >= 11
  73     check_vector_reverse_iterators<std::vector<int, min_allocator<int> > >();
  74 #endif
  75
  76     return true;
  77 }
  78
  79 int main(int, char**) {
  80     test();
  81 #if TEST_STD_VER > 17
  82     static_assert(test());
  83 #endif
  84
  85     return 0;
  86 }