@Test
public void testPrint_TruncateColumns() {

    DataFrameTabularPrintWorker w = new DataFrameTabularPrintWorker(new StringBuilder(), 5, 4);
    assertEquals(System.lineSeparator() +
            "col1 c..2" + System.lineSeparator() +
            "---- ----" + System.lineSeparator() +
            "one     1" + System.lineSeparator() +
            "two     2" + System.lineSeparator() +
            "t..e    3" + System.lineSeparator() +
            "four    4" + System.lineSeparator() +
            "4 rows x 2 columns", w.print(df).toString());
}