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

   1 // Copyright (C) 2019-2022 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();
  43   auto e = c.end();
  44   auto ei = std::ranges::next(b, e);
  45   VERIFY( std::ranges::distance(b, e) == 10 );
  46   VERIFY( std::ranges::distance(ei, b) == -10 );
  47
  48   const auto cb = b;
  49   const auto ce = e;
  50   const auto cei = ei;
  51   VERIFY( std::ranges::distance(cb, ce) == 10 );
  52   VERIFY( std::ranges::distance(cei, cb) == -10 );
  53
  54   test_sized_range<int, random_access_iterator_wrapper> c2(a);
  55   VERIFY( std::ranges::distance(c2) == 10 );
  56 }
  57
  58 void
  59 test02()
  60 {
  61   int a[2] = { };
  62   VERIFY( std::ranges::distance(a) == 2 );
  63
  64   test_range<int, bidirectional_iterator_wrapper> c(a);
  65   VERIFY( std::ranges::distance(c) == 2 );
  66
  67   auto b = c.begin();
  68   auto e = c.end();
  69   VERIFY( std::ranges::distance(b, e) == 2 );
  70
  71   const auto cb = b;
  72   const auto ce = e;
  73   VERIFY( std::ranges::distance(cb, ce) == 2 );
  74
  75   test_sized_range<int, bidirectional_iterator_wrapper> c2(a);
  76   VERIFY( std::ranges::distance(c2) == 2 );
  77 }
  78
  79 void
  80 test03()
  81 {
  82   int a[3] = { };
  83   test_range<int, forward_iterator_wrapper> c(a);
  84   VERIFY( std::ranges::distance(c) == 3 );
  85
  86   auto b = c.begin();
  87   auto e = c.end();
  88   VERIFY( std::ranges::distance(b, e) == 3 );
  89
  90   const auto cb = b;
  91   const auto ce = e;
  92   VERIFY( std::ranges::distance(cb, ce) == 3 );
  93
  94   test_sized_range<int, forward_iterator_wrapper> c2(a);
  95   VERIFY( std::ranges::distance(c2) == 3 );
  96 }
  97
  98 void
  99 test04()
 100 {
 101   int a[4] = { };
 102   test_range<int, input_iterator_wrapper> c(a);
 103   static_assert( std::ranges::range<decltype(c)> );
 104
 105   VERIFY( std::ranges::distance(c) == 4 );
 106   // first call to distance has traversed the range:
 107   VERIFY( std::ranges::distance(c) == 0 );
 108
 109   c = test_range<int, input_iterator_wrapper>(a);
 110   auto b = c.begin();
 111   auto e = c.end();
 112   VERIFY( std::ranges::distance(b, e) == 4 );
 113
 114   test_range<int, input_iterator_wrapper> c2(a);
 115   const auto cb = c2.begin();
 116   const auto ce = c2.end();
 117   VERIFY( std::ranges::distance(cb, ce) == 4 );
 118
 119   test_sized_range<int, input_iterator_wrapper> c3(a);
 120   VERIFY( std::ranges::distance(c3) == 4 );
 121   // first call to distance just called size() without affecting the range:
 122   VERIFY( std::ranges::distance(c3) == 4 );
 123 }
 124
 125 void
 126 test05()
 127 {
 128   int a[5] = { };
 129   test_range<int, output_iterator_wrapper> c(a);
 130   VERIFY( std::ranges::distance(c) == 5 );
 131
 132   test_range<int, output_iterator_wrapper> c2(a);
 133   auto b = c2.begin();
 134   auto e = c2.end();
 135   VERIFY( std::ranges::distance(b, e) == 5 );
 136
 137   test_range<int, output_iterator_wrapper> c3(a);
 138   const auto cb = c3.begin();
 139   const auto ce = c3.end();
 140   VERIFY( std::ranges::distance(cb, ce) == 5 );
 141
 142   test_sized_range<int, output_iterator_wrapper> c4(a);
 143   VERIFY( std::ranges::distance(c4) == 5 );
 144   // first call to distance just called size() without affecting the range:
 145   VERIFY( std::ranges::distance(c4) == 5 );
 146 }
 147
 148 int
 149 main()
 150 {
 151   test01();
 152   test02();
 153   test03();
 154   test04();
 155   test05();
 156 }