@Override
      public boolean evaluate() throws IOException {
        HMaster master = getMiniHBaseCluster().getMaster();
        if (master == null) return false;
        AssignmentManager am = master.getAssignmentManager();
        if (am == null) return false;
        return !am.hasRegionsInTransition();
      }
Returns a {@link Predicate} for checking that there are no regions in transition in master
hbase-testing-util/src/main/java/org/apache/hadoop/hbase/HBaseTestingUtility.java