libstdc++-v3/testsuite/20_util/optional/cons/move.cc

   1 // { dg-do run { target c++17 }  }
   2
   3 // Copyright (C) 2013-2024 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the
   7 // terms of the GNU General Public License as published by the
   8 // Free Software Foundation; either version 3, or (at your option)
   9 // any later version.
  10
  11 // This library is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15
  16 // You should have received a copy of the GNU General Public License along
  17 // with this library; see the file COPYING3.  If not see
  18 // <http://www.gnu.org/licenses/>.
  19
  20 #include <optional>
  21 #include <testsuite_hooks.h>
  22
  23 struct tracker
  24 {
  25   tracker(int value) : value(value) { ++count; }
  26   ~tracker() { --count; }
  27
  28   tracker(tracker const& other) : value(other.value) { ++count; }
  29   tracker(tracker&& other) : value(other.value)
  30   {
  31     other.value = -1;
  32     ++count;
  33   }
  34
  35   tracker& operator=(tracker const&) = default;
  36   tracker& operator=(tracker&&) = default;
  37
  38   int value;
  39
  40   static int count;
  41 };
  42
  43 int tracker::count = 0;
  44
  45 struct exception { };
  46
  47 struct throwing_move
  48 {
  49   throwing_move() = default;
  50   throwing_move(throwing_move const&) { throw exception {}; }
  51 };
  52
  53 int main()
  54 {
  55   // [20.5.4.1] Constructors
  56
  57   {
  58     std::optional<long> o;
  59     auto moved_to = std::move(o);
  60     VERIFY( !moved_to );
  61     VERIFY( !o );
  62   }
  63
  64   {
  65     const long val = 0x1234ABCD;
  66     std::optional<long> o { std::in_place, val};
  67     auto moved_to = std::move(o);
  68     VERIFY( moved_to );
  69     VERIFY( *moved_to == val );
  70     VERIFY( o && *o == val );
  71   }
  72
  73   {
  74     std::optional<tracker> o;
  75     auto moved_to = std::move(o);
  76     VERIFY( !moved_to );
  77     VERIFY( tracker::count == 0 );
  78     VERIFY( !o );
  79   }
  80
  81   {
  82     std::optional<tracker> o { std::in_place, 333 };
  83     auto moved_to = std::move(o);
  84     VERIFY( moved_to );
  85     VERIFY( moved_to->value == 333 );
  86     VERIFY( tracker::count == 2 );
  87     VERIFY( o && o->value == -1 );
  88   }
  89
  90   enum outcome { nothrow, caught, bad_catch };
  91
  92   {
  93     outcome result = nothrow;
  94     std::optional<throwing_move> o;
  95
  96     try
  97     {
  98       auto moved_to = std::move(o);
  99     }
 100     catch(exception const&)
 101     { result = caught; }
 102     catch(...)
 103     { result = bad_catch; }
 104
 105     VERIFY( result == nothrow );
 106   }
 107
 108   {
 109     outcome result = nothrow;
 110     std::optional<throwing_move> o { std::in_place };
 111
 112     try
 113     {
 114       auto moved_to = std::move(o);
 115     }
 116     catch(exception const&)
 117     { result = caught; }
 118     catch(...)
 119     { result = bad_catch; }
 120
 121     VERIFY( result == caught );
 122   }
 123
 124   VERIFY( tracker::count == 0 );
 125 }