Add tests for enable_shared_from

test/weak_from_test.cpp

@@ -0,0 +1,97 @@
+
+// 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();
+}