cppbind: from_nasal/to_nasal for SGWeakReferenced based objects

simgear/nasal/cppbind/Ghost.hxx

@@ -1067,7 +1067,11 @@ from_nasal_helper(naContext c, naRef ref, const T*)
  * Convert any pointer to a SGReference based object to a ghost.
  */
 template<class T>
-typename boost::enable_if<boost::is_base_of<SGReferenced, T>, naRef>::type
+typename boost::enable_if_c<
+     boost::is_base_of<SGReferenced, T>::value
+  || boost::is_base_of<SGWeakReferenced, T>::value,
+  naRef
+>::type
 to_nasal_helper(naContext c, T* ptr)
 {
   return nasal::Ghost<SGSharedPtr<T> >::create(c, SGSharedPtr<T>(ptr));
@@ -1077,8 +1081,15 @@ to_nasal_helper(naContext c, T* ptr)
  * Convert nasal ghosts/hashes to pointer (of a SGReference based ghost).
  */
 template<class T>
-typename boost::enable_if<
+typename boost::enable_if_c<
-  boost::is_base_of<SGReferenced, typename boost::remove_pointer<T>::type>,
+     boost::is_base_of<
+       SGReferenced,
+       typename boost::remove_pointer<T>::type
+     >::value
+  || boost::is_base_of<
+       SGWeakReferenced,
+       typename boost::remove_pointer<T>::type
+     >::value,
   T
 >::type
 from_nasal_helper(naContext c, naRef ref, const T*)

simgear/nasal/cppbind/cppbind_test.cxx

@@ -82,10 +82,17 @@ class SGReferenceBasedClass:
 
 };
 
+class SGWeakReferenceBasedClass:
+  public SGWeakReferenced
+{
+
+};
+
 typedef boost::shared_ptr<Derived> DerivedPtr;
 typedef boost::shared_ptr<DoubleDerived> DoubleDerivedPtr;
 typedef boost::shared_ptr<DoubleDerived2> DoubleDerived2Ptr;
 typedef SGSharedPtr<SGReferenceBasedClass> SGRefBasedPtr;
+typedef SGSharedPtr<SGWeakReferenceBasedClass> SGWeakRefBasedPtr;
 
 typedef boost::weak_ptr<Derived> DerivedWeakPtr;
 
@@ -228,6 +235,21 @@ int main(int argc, char* argv[])
 
   Ghost<DerivedWeakPtr>::init("DerivedWeakPtr");
   Ghost<SGRefBasedPtr>::init("SGRefBasedPtr");
+  Ghost<SGWeakRefBasedPtr>::init("SGWeakRefBasedPtr");
+
+  SGWeakRefBasedPtr weak_ptr(new SGWeakReferenceBasedClass());
+  naRef nasal_ref = to_nasal(c, weak_ptr),
+        nasal_ptr = to_nasal(c, weak_ptr.get());
+
+  VERIFY( naIsGhost(nasal_ref) );
+  VERIFY( naIsGhost(nasal_ptr) );
+
+  SGWeakRefBasedPtr ptr1 = from_nasal<SGWeakRefBasedPtr>(c, nasal_ref),
+                    ptr2 = from_nasal<SGWeakRefBasedPtr>(c, nasal_ptr);
+
+  VERIFY( weak_ptr == ptr1 );
+  VERIFY( weak_ptr == ptr2 );
+
 
   VERIFY( Ghost<BasePtr>::isInit() );
   nasal::to_nasal(c, DoubleDerived2Ptr());