{"ast_node_type":"function","tokens":[{"end":97,"kind":"keyword","start":0,"text":"fn"}]}
    fn call_has_self_arg(&self, source: PathSource<'_, '_, '_>) -> Option<(Span, Option<Span>)> {
    /// return the span of whole call and the span for all arguments expect the first one (`self`).
        let mut has_self_arg = None;