ceph/src/boost/libs/iterator/test/distance_test.cpp

   1 // Copyright (C) 2017 Michel Morin.
   2 //
   3 // Distributed under the Boost Software License, Version 1.0.
   4 // (See accompanying file LICENSE_1_0.txt or copy at
   5 // http://www.boost.org/LICENSE_1_0.txt)
   6
   7 #include <vector>
   8 #include <list>
   9 #include <boost/container/slist.hpp>
  10 #include <boost/core/lightweight_test.hpp>
  11 #include <boost/iterator/distance.hpp>
  12 #include <boost/iterator/transform_iterator.hpp>
  13
  14 int twice(int x) { return x + x; }
  15
  16 template <typename Iterator>
  17 void test_distance(Iterator it_from, Iterator it_to, int n)
  18 {
  19     BOOST_TEST(boost::distance(it_from, it_to) == n);
  20 }
  21
  22 int main()
  23 {
  24     int array[3] = {1, 2, 3};
  25     int* ptr1 = array;
  26     int* ptr2 = array + 3;
  27
  28     {
  29         test_distance(ptr1, ptr2,  3);
  30         test_distance(ptr2, ptr1, -3);
  31
  32         test_distance(
  33             boost::make_transform_iterator(ptr1, twice)
  34           , boost::make_transform_iterator(ptr2, twice)
  35           , 3
  36         );
  37         test_distance(
  38             boost::make_transform_iterator(ptr2, twice)
  39           , boost::make_transform_iterator(ptr1, twice)
  40           , -3
  41         );
  42     }
  43
  44     {
  45         std::vector<int> ints(ptr1, ptr2);
  46         test_distance(ints.begin(), ints.end(),  3);
  47         test_distance(ints.end(), ints.begin(), -3);
  48
  49         test_distance(
  50             boost::make_transform_iterator(ints.begin(), twice)
  51           , boost::make_transform_iterator(ints.end(), twice)
  52           , 3
  53         );
  54         test_distance(
  55             boost::make_transform_iterator(ints.end(), twice)
  56           , boost::make_transform_iterator(ints.begin(), twice)
  57           , -3
  58         );
  59     }
  60
  61     {
  62         std::list<int> ints(ptr1, ptr2);
  63         test_distance(ints.begin(), ints.end(),  3);
  64
  65         test_distance(
  66             boost::make_transform_iterator(ints.begin(), twice)
  67           , boost::make_transform_iterator(ints.end(), twice)
  68           , 3
  69         );
  70     }
  71
  72     {
  73         boost::container::slist<int> ints(ptr1, ptr2);
  74         test_distance(ints.begin(), ints.end(),  3);
  75
  76         test_distance(
  77             boost::make_transform_iterator(ints.begin(), twice)
  78           , boost::make_transform_iterator(ints.end(), twice)
  79           , 3
  80         );
  81     }
  82
  83     return boost::report_errors();
  84 }