libstdc++-v3/testsuite/24_iterators/range_operations/distance.cc

   1 // Copyright (C) 2019 Free Software Foundation, Inc.
   2 //
   3 // This file is part of the GNU ISO C++ Library.  This library is free
   4 // software; you can redistribute it and/or modify it under the
   5 // terms of the GNU General Public License as published by the
   6 // Free Software Foundation; either version 3, or (at your option)
   7 // any later version.
   8
   9 // This library is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13
  14 // You should have received a copy of the GNU General Public License along
  15 // with this library; see the file COPYING3.  If not see
  16 // <http://www.gnu.org/licenses/>.
  17
  18 // { dg-options "-std=gnu++2a" }
  19 // { dg-do run { target c++2a } }
  20
  21 #include <iterator>
  22 #include <testsuite_hooks.h>
  23 #include <testsuite_iterators.h>
  24
  25 using __gnu_test::test_range;
  26 using __gnu_test::test_sized_range;
  27 using __gnu_test::random_access_iterator_wrapper;
  28 using __gnu_test::bidirectional_iterator_wrapper;
  29 using __gnu_test::forward_iterator_wrapper;
  30 using __gnu_test::input_iterator_wrapper;
  31 using __gnu_test::output_iterator_wrapper;
  32
  33 void
  34 test01()
  35 {
  36   int a[10] = { };
  37   VERIFY( std::ranges::distance(a) == 10 );
  38
  39   test_range<int, random_access_iterator_wrapper> c(a);
  40   VERIFY( std::ranges::distance(c) == 10 );
  41
  42   auto b = c.begin(), e = c.end();
  43   VERIFY( std::ranges::distance(b, e) == 10 );
  44   VERIFY( std::ranges::distance(e, b) == -10 );
  45
  46   const auto cb = b, ce = e;
  47   VERIFY( std::ranges::distance(cb, ce) == 10 );
  48   VERIFY( std::ranges::distance(ce, cb) == -10 );
  49
  50   test_sized_range<int, random_access_iterator_wrapper> c2(a);
  51   VERIFY( std::ranges::distance(c2) == 10 );
  52 }
  53
  54 void
  55 test02()
  56 {
  57   int a[2] = { };
  58   VERIFY( std::ranges::distance(a) == 2 );
  59
  60   test_range<int, bidirectional_iterator_wrapper> c(a);
  61   VERIFY( std::ranges::distance(c) == 2 );
  62
  63   auto b = c.begin(), e = c.end();
  64   VERIFY( std::ranges::distance(b, e) == 2 );
  65
  66   const auto cb = b, ce = e;
  67   VERIFY( std::ranges::distance(cb, ce) == 2 );
  68
  69   test_sized_range<int, bidirectional_iterator_wrapper> c2(a);
  70   VERIFY( std::ranges::distance(c2) == 2 );
  71 }
  72
  73 void
  74 test03()
  75 {
  76   int a[3] = { };
  77   test_range<int, forward_iterator_wrapper> c(a);
  78   VERIFY( std::ranges::distance(c) == 3 );
  79
  80   auto b = c.begin(), e = c.end();
  81   VERIFY( std::ranges::distance(b, e) == 3 );
  82
  83   const auto cb = b, ce = e;
  84   VERIFY( std::ranges::distance(cb, ce) == 3 );
  85
  86   test_sized_range<int, forward_iterator_wrapper> c2(a);
  87   VERIFY( std::ranges::distance(c2) == 3 );
  88 }
  89
  90 void
  91 test04()
  92 {
  93   int a[4] = { };
  94   test_range<int, input_iterator_wrapper> c(a);
  95   static_assert( std::ranges::range<decltype(c)> );
  96
  97   VERIFY( std::ranges::distance(c) == 4 );
  98   // first call to distance has traversed the range:
  99   VERIFY( std::ranges::distance(c) == 0 );
 100
 101   c = test_range<int, input_iterator_wrapper>(a);
 102   auto b = c.begin(), e = c.end();
 103   VERIFY( std::ranges::distance(b, e) == 4 );
 104
 105   test_range<int, input_iterator_wrapper> c2(a);
 106   const auto cb = c2.begin(), ce = c2.end();
 107   VERIFY( std::ranges::distance(cb, ce) == 4 );
 108
 109   test_sized_range<int, input_iterator_wrapper> c3(a);
 110   VERIFY( std::ranges::distance(c3) == 4 );
 111   // first call to distance just called size() without affecting the range:
 112   VERIFY( std::ranges::distance(c3) == 4 );
 113 }
 114
 115 void
 116 test05()
 117 {
 118   int a[5] = { };
 119   test_range<int, output_iterator_wrapper> c(a);
 120   VERIFY( std::ranges::distance(c) == 5 );
 121
 122   test_range<int, output_iterator_wrapper> c2(a);
 123   auto b = c2.begin();
 124   auto e = c2.end();
 125   VERIFY( std::ranges::distance(b, e) == 5 );
 126
 127   test_range<int, output_iterator_wrapper> c3(a);
 128   const auto cb = c3.begin();
 129   const auto ce = c3.end();
 130   VERIFY( std::ranges::distance(cb, ce) == 5 );
 131
 132   test_sized_range<int, output_iterator_wrapper> c4(a);
 133   VERIFY( std::ranges::distance(c4) == 5 );
 134   // first call to distance just called size() without affecting the range:
 135   VERIFY( std::ranges::distance(c4) == 5 );
 136 }
 137
 138 int
 139 main()
 140 {
 141   test01();
 142   test02();
 143   test03();
 144   test04();
 145   test05();
 146 }