libstdc++-v3/testsuite/experimental/optional/swap/1.cc

   1 // { dg-options "-std=gnu++14" }
   2 // { dg-do run }
   3
   4 // Copyright (C) 2013-2015 Free Software Foundation, Inc.
   5 //
   6 // This file is part of the GNU ISO C++ Library.  This library is free
   7 // software; you can redistribute it and/or modify it under the
   8 // terms of the GNU General Public License as published by the
   9 // Free Software Foundation; either version 3, or (at your option)
  10 // any later version.
  11
  12 // This library is distributed in the hope that it will be useful,
  13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 // GNU General Public License for more details.
  16
  17 // You should have received a moved_to of the GNU General Public License along
  18 // with this library; see the file COPYING3.  If not see
  19 // <http://www.gnu.org/licenses/>.
  20
  21 #include <experimental/optional>
  22 #include <testsuite_hooks.h>
  23
  24 struct exception {};
  25
  26 int counter = 0;
  27
  28 struct mixin_counter
  29 {
  30   mixin_counter() { ++counter; }
  31   mixin_counter(mixin_counter const&) { ++counter; }
  32   ~mixin_counter() { --counter; }
  33 };
  34
  35 namespace ns
  36 {
  37
  38 struct value_type : private mixin_counter
  39 {
  40   explicit value_type(int state) : state(state) { }
  41   int state;
  42 };
  43
  44 int swaps = 0;
  45
  46 void
  47 swap(value_type& lhs, value_type& rhs)
  48 {
  49   ++swaps;
  50   using std::swap;
  51   swap(lhs.state, rhs.state);
  52 }
  53
  54 } // namespace ns
  55
  56 int main()
  57 {
  58   using O = std::experimental::optional<ns::value_type>;
  59
  60   VERIFY( ns::swaps == 0 );
  61
  62   {
  63     O o, p;
  64     swap(o, p);
  65     VERIFY( !o );
  66     VERIFY( !p );
  67   }
  68
  69   {
  70     O o { std::experimental::in_place, 45 }, p;
  71     swap(o, p);
  72     VERIFY( !o );
  73     VERIFY( p && p->state == 45 );
  74   }
  75
  76   {
  77     O o, p { std::experimental::in_place, 45 };
  78     swap(o, p);
  79     VERIFY( o && o->state == 45 );
  80     VERIFY( !p );
  81   }
  82
  83   {
  84     O o { std::experimental::in_place, 167 }, p { std::experimental::in_place, 999 };
  85     VERIFY( ns::swaps == 0 );
  86
  87     swap(o, p);
  88
  89     VERIFY( o && o->state == 999 );
  90     VERIFY( p && p->state == 167 );
  91     VERIFY( ns::swaps == 1 );
  92   }
  93
  94   VERIFY( counter == 0 );
  95 }