{"ast_node_type":"variable","tokens":[{"end":90,"kind":"keyword","start":0,"text":"let"}]}
        let from_node = SourceFile::parse(from, Edition::CURRENT).tree().syntax().clone();
    fn check_diff(from: &str, to: &str, expected_diff: Expect) {
        let to_node = SourceFile::parse(to, Edition::CURRENT).tree().syntax().clone();