| 1 | |
|---|---|
| 2 | // weak_from_test.cpp |
| 3 | // |
| 4 | // Copyright 2019 Peter Dimov |
| 5 | // |
| 6 | // Distributed under the Boost Software License, Version 1.0. |
| 7 | // http://www.boost.org/LICENSE_1_0.txt) |
| 8 | |
| 9 | #include <boost/smart_ptr/enable_shared_from.hpp> |
| 10 | #include <boost/shared_ptr.hpp> |
| 11 | #include <boost/weak_ptr.hpp> |
| 12 | #include <boost/core/lightweight_test.hpp> |
| 13 | |
| 14 | // |
| 15 | |
| 16 | class X |
| 17 | { |
| 18 | private: |
| 19 | |
| 20 | int m_; |
| 21 | |
| 22 | public: |
| 23 | |
| 24 | X(): m_() {} |
| 25 | }; |
| 26 | |
| 27 | class Y: public boost::enable_shared_from |
| 28 | { |
| 29 | }; |
| 30 | |
| 31 | class Z: public X, public Y |
| 32 | { |
| 33 | public: |
| 34 | |
| 35 | boost::weak_ptr<Z> weak_from_this() |
| 36 | { |
| 37 | return boost::weak_from( p: this ); |
| 38 | } |
| 39 | }; |
| 40 | |
| 41 | void null_deleter( void const* ) |
| 42 | { |
| 43 | } |
| 44 | |
| 45 | int main() |
| 46 | { |
| 47 | boost::shared_ptr<Z> sp( new Z ); |
| 48 | boost::weak_ptr<Z> p( sp ); |
| 49 | |
| 50 | { |
| 51 | boost::weak_ptr<Z> q = sp->weak_from_this(); |
| 52 | |
| 53 | BOOST_TEST_EQ( p.lock(), q.lock() ); |
| 54 | BOOST_TEST( !( p < q ) && !( q < p ) ); |
| 55 | } |
| 56 | |
| 57 | Z v2( *sp ); |
| 58 | |
| 59 | { |
| 60 | boost::weak_ptr<Z> q = v2.weak_from_this(); |
| 61 | BOOST_TEST( q.expired() ); |
| 62 | } |
| 63 | |
| 64 | *sp = Z(); |
| 65 | |
| 66 | { |
| 67 | boost::weak_ptr<Z> q = sp->weak_from_this(); |
| 68 | |
| 69 | BOOST_TEST_EQ( p.lock(), q.lock() ); |
| 70 | BOOST_TEST( !( p < q ) && !( q < p ) ); |
| 71 | } |
| 72 | |
| 73 | { |
| 74 | boost::shared_ptr<Z> sp2( sp.get(), null_deleter ); |
| 75 | } |
| 76 | |
| 77 | { |
| 78 | boost::weak_ptr<Z> q = sp->weak_from_this(); |
| 79 | |
| 80 | BOOST_TEST_EQ( p.lock(), q.lock() ); |
| 81 | BOOST_TEST( !( p < q ) && !( q < p ) ); |
| 82 | } |
| 83 | |
| 84 | { |
| 85 | boost::weak_ptr<Z> p2 = sp->weak_from_this(); |
| 86 | |
| 87 | BOOST_TEST( !p.expired() ); |
| 88 | BOOST_TEST( !p2.expired() ); |
| 89 | |
| 90 | sp.reset(); |
| 91 | |
| 92 | BOOST_TEST( p.expired() ); |
| 93 | BOOST_TEST( p2.expired() ); |
| 94 | } |
| 95 | |
| 96 | return boost::report_errors(); |
| 97 | } |
| 98 |