private void testRBPCounts(final ReadBackedPileup rbp, RBPCountTest expected) {
   for (int cycles = 0; cycles < 3; cycles++) {
     // multiple cycles to make sure caching is working
     Assert.assertEquals(rbp.getNumberOfElements(), expected.nReads);
     Assert.assertEquals(rbp.depthOfCoverage(), expected.nReads);
     Assert.assertEquals(rbp.getNumberOfDeletions(), expected.nDeletions);
     Assert.assertEquals(rbp.getNumberOfMappingQualityZeroReads(), expected.nMapq0);
   }
 }