{"ast_node_type":"variable","tokens":[{"end":83,"kind":"keyword","start":0,"text":"let"}]}
    let wide_line_col = line_index.to_wide(WideEncoding::Utf16, line_col.unwrap());
    assert_eq!(line_col, Some(LineCol { line: 5, col: 6 }));
    assert_eq!(wide_line_col, Some(WideLineCol { line: 5, col: 4 }));