{"ast_node_type":"other","tokens":[{"end":30,"kind":"keyword","start":0,"text":"assert_eq!(f,"}]}
    assert_eq!(f, Some(func));
    let f = expr_syntax.ancestors().find_map(ast::Fn::cast);
    assert!(expr_syntax.siblings_with_tokens(Direction::Next).any(|it| it.kind() == T!['}']));