pub(crate) fn filename(node: &lib_ruby_parser_nodes::Node) -> String {
let lower = node.lower_name();
match &lower[..] {
"self" | "break" | "const" | "false" | "for" | "if" | "return" | "str" | "super"
| "true" | "while" | "yield" => format!("{}_", lower),
_ => lower,
}
}