Fix-up the handler type to the cause type
@@ -344,7 +344,7 @@ async def invoke_handler(
# For the field-handlers, the old/new/diff values must match the field, not the whole object.
if (True and # for readable indenting
isinstance(cause, causation.ResourceChangingCause) and
- isinstance(handler, handlers_.ResourceHandler) and
+ isinstance(handler, handlers_.ResourceChangingHandler) and
handler.field is not None):
old = dicts.resolve(cause.old, handler.field, None)
new = dicts.resolve(cause.new, handler.field, None)
