How to convert raw `TokenList(Vec<TokenOrValue>)` into a rule?

I am implementing a custom pseudo function transform which changes :deep from

.test :deep(.deep-test) { /**/ }

to

.test[data-v-smth] .deep-test { /**/ }

To visit the custom pseudo function I use

fn visit_selector(&mut self, selector: &mut Selector<'i>) -> Result<(), Self::Error> {
    selector.iter().any(|part| match part {
        Component::NonTSPseudoClass(pseudo_class) => {
            match pseudo_class {
                lightningcss::selector::PseudoClass::CustomFunction { name, arguments } => {
                    println!("{:?}", arguments);
                    true
                },
                _ => false
            }
        },
        _ => false
    });

    Ok(())
}

Now pseudo function has a TokenList inside.

TokenList([Token(Delim('.')), Token(Ident("deep-test"))])

How can I run it through lightningcss to parse as a selector? All the implementations on TokenList are either private or pub(crate) and require some hacking. This also includes .to_css()

The entry point shown is visit_selector, where PseudoClass::CustomFunction exposes a TokenList. Start by tracing the public selector and TokenList APIs around this visitor and the existing visibility boundaries. Done means establishing a supported way to parse the shown .deep-test tokens as a selector, with the result usable for the :deep transform.