private void listIsExpectedSize(List<String> list, int expectedSize, String listName) {
    assertNotNull(listName + " is null", list);
    assertEquals(listName + " doesn't have the expected size " + expectedSize, expectedSize, list.size());
  }
Deep copy a {@link DataNodeConfig}.
@param dataNodeConfig {@link DataNodeConfig} to copy
@return {@link InstanceConfig} of given data node.
ambry-clustermap/src/test/java/com/github/ambry/clustermap/HelixParticipantTest.java