/// <summary>
/// Set the 'args' slot on a python exception object that wraps
/// a CLR exception. This is needed for pickling CLR exceptions as
/// BaseException_reduce will only check the slots, bypassing the
/// __getattr__ implementation, and thus dereferencing a NULL
/// pointer.
/// </summary>
/// <param name="ob">The python object wrapping </param>
internal static void SetArgsAndCause(IntPtr ob)
{
// e: A CLR Exception
Exception e = ExceptionClassObject.ToException(ob);
if (e == null)
{
return;
}
IntPtr args;
if (!string.IsNullOrEmpty(e.Message))
{
args = Runtime.PyTuple_New(1);
IntPtr msg = Runtime.PyUnicode_FromString(e.Message);
Runtime.PyTuple_SetItem(args, 0, msg);
}
else
{
args = Runtime.PyTuple_New(0);
}
Marshal.WriteIntPtr(ob, ExceptionOffset.args, args);
#if PYTHON3
if (e.InnerException != null)
{
IntPtr cause = CLRObject.GetInstHandle(e.InnerException);
Marshal.WriteIntPtr(ob, ExceptionOffset.cause, cause);
}
#endif
}
/// <summary>
/// Create a new ClassBase-derived instance that implements a reflected
/// managed type. The new object will be associated with a generated
/// Python type object.
/// </summary>
private static ClassBase CreateClass(Type type)
{
// Next, select the appropriate managed implementation class.
// Different kinds of types, such as array types or interface
// types, want to vary certain implementation details to make
// sure that the type semantics are consistent in Python.
ClassBase impl;
// Check to see if the given type extends System.Exception. This
// lets us check once (vs. on every lookup) in case we need to
// wrap Exception-derived types in old-style classes
if (type.ContainsGenericParameters)
{
impl = new GenericType(type);
}
else if (type.IsSubclassOf(dtype))
{
impl = new DelegateObject(type);
}
else if (type.IsArray)
{
impl = new ArrayObject(type);
}
else if (type.IsInterface)
{
impl = new InterfaceObject(type);
}
else if (type == typeof(Exception) ||
type.IsSubclassOf(typeof(Exception)))
{
impl = new ExceptionClassObject(type);
}
else if (null != type.GetField("__pyobj__"))
{
impl = new ClassDerivedObject(type);
}
else
{
impl = new ClassObject(type);
}
return(impl);
}