private void verifyString(int resultIndex, String expected, BytesColumnVector resultV) {
    String result = getStringFromBytesColumnVector(resultV, resultIndex);
    Assert.assertEquals(expected, result);
  }
Tests vectorized type cast udfs CastDateToStringWithFormat, CastTimestampToStringWithFormat,
CastStringToDateWithFormat, CastStringToTimestampWithFormat.
ql/src/test/org/apache/hadoop/hive/ql/exec/vector/expressions/TestVectorTypeCastsWithFormat.java