Function difft::diff::unchanged::split_unchanged

fn split_unchanged<'a>(
    lhs_nodes: &[&'a Syntax<'a>],
    rhs_nodes: &[&'a Syntax<'a>],
    change_map: &mut ChangeMap<'a>
) -> Vec<(Vec<&'a Syntax<'a>>, Vec<&'a Syntax<'a>>)>