Tests reading a file containing this ptg.
HSSFWorkbook workbook = loadWorkbook("ErrPtg.xls");
HSSFCell cell = workbook.getSheetAt(0).getRow(3).getCell((short) 0);
assertEquals("Wrong cell value", 4.0, cell.getNumericCellValue(), 0.0);
assertEquals("Wrong cell formula", "ERROR.TYPE(#REF!)", cell.getCellFormula());