fn any_sorted_attr(item:&syn::ExprMatch)->bool{
    item.attrs
        .iter()
        .flat_map(syn::Attribute::parse_meta)
        .any(|meta| meta.name()=="sorted" )
}


#[test]
fn found_any_sorted_attr(){
    let matches=vec![
        (false,"match () { ()=>() }"),
        (false,"#[nothing] match () { ()=>() }"),
        (true ,"#[sorted] match () { ()=>() }"),
        (true ,"#[nothing] #[sorted] match () { ()=>() }"),
    ];

    for (expected,expr) in matches{
        let parsed=syn::parse_str::<syn::Expr>(expr).expect(expr);
        let parsed=match parsed {
            syn::Expr::Match(v)=>v,
            _=>unreachable!(),
        };
        assert_eq!( expected, any_sorted_attr(&parsed) );
    }
}