pub(crate) fn eval_method0(&mut self, method: FnId, self_val: impl Into<Value>) -> VMResult {
        let self_val = self_val.into();
        let args = Args2::new(0);
        self.stack_push(self_val);
        self.invoke_method(method, &args, true)?.handle(self)
    }
Evaluate the method with given `self_val`, `args` and no outer context.
ruruby/src/vm/executor/method.rs