return derivedSuites;
  }

  @Override
  protected SetTestSuiteBuilder<K> createDerivedKeySetSuite(TestSetGenerator<K> keySetGenerator) {
    return keySetGenerator instanceof TestSortedSetGenerator
        ? SortedSetTestSuiteBuilder.using((TestSortedSetGenerator<K>) keySetGenerator)
        : SetTestSuiteBuilder.using(keySetGenerator);
  }

  /**
   * To avoid infinite recursion, test suites with these marker features won't have derived suites

import com.google.common.collect.testing.MapInterfaceTest;
import com.google.common.collect.testing.SampleElements;
import com.google.common.collect.testing.SetTestSuiteBuilder;
import com.google.common.collect.testing.SortedSetTestSuiteBuilder;
import com.google.common.collect.testing.TestSetGenerator;
import com.google.common.collect.testing.TestStringCollectionGenerator;
import com.google.common.collect.testing.TestStringSetGenerator;