Function highlight_name_ref 

fn highlight_name_ref(
    sema: &Semantics<'_, RootDatabase>,
    krate: Option<Crate>,
    bindings_shadow_count: Option<&mut FxHashMap<Name, u32>>,
    binding_hash: &mut Option<u64>,
    is_unsafe_node: &impl Fn(AstPtr<Either<Expr, Pat>>) -> bool,
    syntactic_name_ref_highlighting: bool,
    name_ref: NameRef,
    edition: Edition,
) -> Highlight