Strange error when passing malformed xml

[deemytch]

data = "<?xml version=\"1.0\" encoding=\"utf-8\">\n<request>\n <opcode>0</opcode>\n</request>\n" Nori.new.parse data NoMethodError: undefined method 'add_node' for nil:NilClass
Question sign is omitted at the end of header
Expected kind of "Malformed XML" or "Parsing error', but got a syntax error exception.