let is_macro = !slot.macro_attributes.is_empty();
...
if is_macro {
    // TODO(borrowchk): ...
    let slot = &self.matches_by_id[id.0];
    self.attrs_stack.extend(
        slot.macro_attributes
            .iter()
            .filter(|attr| self.matches_by_id[attr.id.0].r#match.is_none())
            .map(|attr| (attr.id, attr.inner.clone(), Some(id))),
    );
}

use gix_attributes::search::{MetadataCollection, Outcome};
use gix_attributes::Search;
use gix_glob::pattern::Case;

fn main() {
    let attributes =
        b"[attr]mylfs filter=lfs\n*.bin mylfs\nspecial.bin -mylfs\nunspec.bin !mylfs\nvalued.bin mylfs=foo\n";

    let mut search = Search::default();
    let mut collection = MetadataCollection::default();
    search.add_patterns_buffer(
        attributes,
        ".gitattributes".into(),
        Some(std::path::Path::new("")),
        &mut collection,
        true, /* allow macros */
    );

    for path in ["normal.bin", "special.bin", "unspec.bin", "valued.bin"] {
        let mut out = Outcome::default();
        out.initialize_with_selection(&collection, ["filter"]);
        search.pattern_matching_relative_path(path.into(), Case::Sensitive, Some(false), &mut out);

        let filter = out
            .iter_selected()
            .map(|m| format!("{:?}", m.assignment.state))
            .collect::<Vec<_>>()
            .join(", ");
        println!("{path}: filter -> [{filter}]");
    }
}