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// Copyright (C) 2013-2021 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING3. If not see
// <http://www.gnu.org/licenses/>.
namespace assign_4 {
struct exception {};
static int counter = 0;
struct mixin_counter
{
mixin_counter() { ++counter; }
mixin_counter(mixin_counter const&) { ++counter; }
~mixin_counter() { --counter; }
};
struct value_type : private mixin_counter
{
enum state_type
{
zero,
moved_from,
throwing_construction,
throwing_copy,
throwing_copy_assignment,
throwing_move,
throwing_move_assignment,
threw,
};
value_type() = default;
explicit value_type(state_type state_)
: state(state_)
{
throw_if(throwing_construction);
}
value_type(value_type const& other)
: state(other.state)
{
throw_if(throwing_copy);
}
value_type&
operator=(value_type const& other)
{
state = other.state;
throw_if(throwing_copy_assignment);
return *this;
}
value_type(value_type&& other)
: state(other.state)
{
other.state = moved_from;
throw_if(throwing_move);
}
value_type&
operator=(value_type&& other)
{
state = other.state;
other.state = moved_from;
throw_if(throwing_move_assignment);
return *this;
}
void throw_if(state_type match)
{
if(state == match)
{
state = threw;
throw exception {};
}
}
state_type state = zero;
};
static void
test ()
{
using O = gdb::optional<value_type>;
using S = value_type::state_type;
auto const make = [](S s = S::zero) { return value_type { s }; };
enum outcome_type { nothrow, caught, bad_catch };
// Check value assignment for engaged optional
{
O o = make();
value_type v = make(S::throwing_copy);
o = v;
VERIFY( o && o->state == S::throwing_copy);
}
{
O o = make();
value_type v = make(S::throwing_move);
o = std::move(v);
VERIFY( o && o->state == S::throwing_move);
}
{
ATTRIBUTE_UNUSED outcome_type outcome {};
O o = make();
value_type v = make(S::throwing_copy_assignment);
try
{
o = v;
}
catch(exception const&)
{ outcome = caught; }
catch(...)
{ outcome = bad_catch; }
VERIFY( o && o->state == S::threw );
}
{
ATTRIBUTE_UNUSED outcome_type outcome {};
O o = make();
value_type v = make(S::throwing_move_assignment);
try
{
o = std::move(v);
}
catch(exception const&)
{ outcome = caught; }
catch(...)
{ outcome = bad_catch; }
VERIFY( o && o->state == S::threw );
}
VERIFY( counter == 0 );
}
} // namespace assign_4
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