return ImmutableMap.of(entry.getKey(), entry.getValue());
      default:
        return new ImmutableEnumMap<>(map);
    }
  }

  private final transient EnumMap<K, V> delegate;

  private ImmutableEnumMap(EnumMap<K, V> delegate) {
    this.delegate = delegate;
    checkArgument(!delegate.isEmpty());
  }

  @Override
  UnmodifiableIterator<K> keyIterator() {

        return ImmutableMap.of(entry.getKey(), entry.getValue());
      default:
        return new ImmutableEnumMap<>(map);
    }
  }

  private final transient EnumMap<K, V> delegate;

  private ImmutableEnumMap(EnumMap<K, V> delegate) {
    this.delegate = delegate;
    checkArgument(!delegate.isEmpty());
  }

  @Override
  UnmodifiableIterator<K> keyIterator() {

import java.util.Map;
import java.util.Map.Entry;

/**
 * GWT emulation of {@link ImmutableEnumMap}. The type parameter is not bounded by {@code Enum<E>}
 * to avoid code-size bloat.
 *
 * @author Hayward Chan
 */
@ElementTypesAreNonnullByDefault
final class ImmutableEnumMap<K, V> extends ForwardingImmutableMap<K, V> {
  static <K, V> ImmutableMap<K, V> asImmutable(Map<K, V> map) {

        map.put(entry.getKey(), entry.getValue());
      }
      return Maps.immutableEnumMap(map);
    }
  }

  @J2ktIncompatible
  @GwtIncompatible // suite
  public static Test suite() {
    TestSuite suite = new TestSuite();
    suite.addTest(
        MapTestSuiteBuilder.using(new ImmutableEnumMapGenerator())
            .named("Maps.immutableEnumMap")
            .withFeatures(CollectionSize.ANY, SERIALIZABLE, ALLOWS_NULL_QUERIES)

        map.put(entry.getKey(), entry.getValue());
      }
      return Maps.immutableEnumMap(map);
    }
  }

  @J2ktIncompatible
  @GwtIncompatible // suite
  public static Test suite() {
    TestSuite suite = new TestSuite();
    suite.addTest(
        MapTestSuiteBuilder.using(new ImmutableEnumMapGenerator())
            .named("Maps.immutableEnumMap")
            .withFeatures(CollectionSize.ANY, SERIALIZABLE, ALLOWS_NULL_QUERIES)

      for (Entry<AnEnum, String> entry : entries) {
        // checkArgument(!map.containsKey(entry.getKey()));
        map.put(entry.getKey(), entry.getValue());
      }
      return Maps.immutableEnumMap(map);
    }
  }

  public static class ImmutableMapCopyOfEnumMapGenerator extends TestEnumMapGenerator {
    @Override
    protected Map<AnEnum, String> create(Entry<AnEnum, String>[] entries) {

      for (Entry<AnEnum, String> entry : entries) {
        // checkArgument(!map.containsKey(entry.getKey()));
        map.put(entry.getKey(), entry.getValue());
      }
      return Maps.immutableEnumMap(map);
    }
  }

  public static class ImmutableMapCopyOfEnumMapGenerator extends TestEnumMapGenerator {
    @Override
    protected Map<AnEnum, String> create(Entry<AnEnum, String>[] entries) {

      } else {
        other.map.forEach(this::put);
        return this;
      }
    }

    ImmutableMap<K, V> toImmutableMap() {
      return (map == null) ? ImmutableMap.<K, V>of() : ImmutableEnumMap.asImmutable(map);
    }
  }

  @GwtIncompatible
  static <T extends @Nullable Object, K extends Comparable<? super K>, V>
      Collector<T, ?, ImmutableRangeMap<K, V>> toImmutableRangeMap(

      } else {
        other.map.forEach(this::put);
        return this;
      }
    }

    ImmutableMap<K, V> toImmutableMap() {
      return (map == null) ? ImmutableMap.<K, V>of() : ImmutableEnumMap.asImmutable(map);
    }
  }

  @GwtIncompatible
  static <T extends @Nullable Object, K extends Comparable<? super K>, V>
      Collector<T, ?, ImmutableRangeMap<K, V>> toImmutableRangeMap(

      @SuppressWarnings({"unchecked", "rawtypes"})
      // immutable collections are safe for covariant casts
      // and getting the generics right for EnumMap is difficult to impossible
      ImmutableMap<K, V> result = ImmutableEnumMap.asImmutable(new EnumMap(enumMap));
      return result;
    }

    int size = map.size();
    switch (size) {
      case 0:
        return of();
      case 1: