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// weak_from_test.cpp
//
// Copyright 2019 Peter Dimov
//
// Distributed under the Boost Software License, Version 1.0.
// http://www.boost.org/LICENSE_1_0.txt)
#include <boost/smart_ptr/enable_shared_from.hpp>
#include <boost/shared_ptr.hpp>
#include <boost/weak_ptr.hpp>
#include <boost/core/lightweight_test.hpp>
//
class X
{
private:
int m_;
public:
X(): m_() {}
};
class Y: public boost::enable_shared_from
{
};
class Z: public X, public Y
{
public:
boost::weak_ptr<Z> weak_from_this()
{
return boost::weak_from( this );
}
};
void null_deleter( void const* )
{
}
int main()
{
boost::shared_ptr<Z> sp( new Z );
boost::weak_ptr<Z> p( sp );
{
boost::weak_ptr<Z> q = sp->weak_from_this();
BOOST_TEST_EQ( p.lock(), q.lock() );
BOOST_TEST( !( p < q ) && !( q < p ) );
}
Z v2( *sp );
{
boost::weak_ptr<Z> q = v2.weak_from_this();
BOOST_TEST( q.expired() );
}
*sp = Z();
{
boost::weak_ptr<Z> q = sp->weak_from_this();
BOOST_TEST_EQ( p.lock(), q.lock() );
BOOST_TEST( !( p < q ) && !( q < p ) );
}
{
boost::shared_ptr<Z> sp2( sp.get(), null_deleter );
}
{
boost::weak_ptr<Z> q = sp->weak_from_this();
BOOST_TEST_EQ( p.lock(), q.lock() );
BOOST_TEST( !( p < q ) && !( q < p ) );
}
{
boost::weak_ptr<Z> p2 = sp->weak_from_this();
BOOST_TEST( !p.expired() );
BOOST_TEST( !p2.expired() );
sp.reset();
BOOST_TEST( p.expired() );
BOOST_TEST( p2.expired() );
}
return boost::report_errors();
}
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