@Test
void testCompare() {

  String unitA = "P";
  long valueA = 1;
  String unitB = "p";
  long valueB = 2;
  assertEquals(1,
      UnitsConversionUtil.compare(unitA, valueA, unitB, valueB));
  assertEquals(-1,
      UnitsConversionUtil.compare(unitB, valueB, unitA, valueA));
  assertEquals(0,
      UnitsConversionUtil.compare(unitA, valueA, unitA, valueA));
  assertEquals(-1,
      UnitsConversionUtil.compare(unitA, valueA, unitA, valueB));
  assertEquals(1,
      UnitsConversionUtil.compare(unitA, valueB, unitA, valueA));
  unitB = "T";
  assertEquals(1,
      UnitsConversionUtil.compare(unitA, valueA, unitB, valueB));
  assertEquals(-1,
      UnitsConversionUtil.compare(unitB, valueB, unitA, valueA));
  assertEquals(0,
      UnitsConversionUtil.compare(unitA, valueA, unitB, 1000L));
  unitA = "p";
  unitB = "n";
  assertEquals(-1,
      UnitsConversionUtil.compare(unitA, valueA, unitB, valueB));
  assertEquals(1,
      UnitsConversionUtil.compare(unitB, valueB, unitA, valueA));
  assertEquals(0,
      UnitsConversionUtil.compare(unitA, 1000L, unitB, valueA));
}