return left.getKey().compareTo(right.getKey());
        }
      }.sortedCopy(insertionOrder);
    }
  }

  public static class ImmutableMapValuesAsSingletonSetGenerator
      implements TestMapGenerator<String, Collection<Integer>> {

    @Override
    public SampleElements<Entry<String, Collection<Integer>>> samples() {
      return new SampleElements<>(

import com.google.common.collect.testing.google.MapGenerators.ImmutableMapValueListGenerator;
import com.google.common.collect.testing.google.MapGenerators.ImmutableMapValuesAsSingletonSetGenerator;
import com.google.common.testing.CollectorTester;
import com.google.common.testing.EqualsTester;
import com.google.common.testing.NullPointerTester;
import java.io.ByteArrayOutputStream;

import com.google.common.collect.testing.google.MapGenerators.ImmutableMapValueListGenerator;
import com.google.common.collect.testing.google.MapGenerators.ImmutableMapValuesAsSingletonSetGenerator;
import com.google.common.testing.EqualsTester;
import com.google.common.testing.NullPointerTester;
import java.io.ByteArrayOutputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;