first attempt at a Cairo macro

lib.cairo

fn r() -> u128 {
    let a = wad!(1.23);
    a
}

#[cfg(test)]
mod tests {
    #[test]
    fn it_works() {
        assert!(super::r() == 1230000000000000000);
        assert!(wad!(2.56) == 2560000000000000000);
        assert!(wad!(3.14) == wad!(3.14));
    }
}

lib.rs

use cairo_lang_macro::{inline_macro, ProcMacroResult, TokenStream};
use cairo_lang_parser::utils::SimpleParserDatabase;
use cairo_lang_syntax::node::kind::SyntaxKind::Arg;
use num_traits::cast::ToPrimitive;

#[inline_macro]
pub fn wad(token_stream: TokenStream) -> ProcMacroResult {
    let db = SimpleParserDatabase::default();
    let (parsed, _diag) = db.parse_virtual_with_diagnostics(token_stream);
    let wad = parsed.descendants(&db).find_map(|node| {
        if let Arg = node.kind(&db) {
            Some(node.get_text(&db).to_string())
        } else {
            None
        }
    });

    let wad: f64 = wad.unwrap().parse::<f64>().unwrap() * 1e18;
    let wad: i64 = wad.to_i64().unwrap();
    let ts = TokenStream::new((wad).to_string());
    ProcMacroResult::new(ts)
}