Function decode_event_spec_value_from_reader 

pub fn decode_event_spec_value_from_reader(
    ty: &ContractType,
    reader: &mut BufReader<'_>,
    type_defs: &TypeDefIndex<'_>,
    path: &str,
    remaining_values: &mut usize,
) -> Result<Value, Error>

Decode one event value while rejecting enum discriminants absent from the spec.