assertEquals(Currency.class, bimap.keyType());
  }

  @GwtIncompatible // valueType
  public void testValueType() {
    EnumBiMap<Currency, Country> bimap = EnumBiMap.create(Currency.class, Country.class);
    assertEquals(Country.class, bimap.valueType());
  }

  public void testIterationOrder() {
    // The enum orderings are alphabetical, leading to the bimap and its inverse

    assertEquals(Currency.class, bimap.keyType());
  }

  @GwtIncompatible // valueType
  public void testValueType() {
    EnumBiMap<Currency, Country> bimap = EnumBiMap.create(Currency.class, Country.class);
    assertEquals(Country.class, bimap.valueType());
  }

  public void testIterationOrder() {
    // The enum orderings are alphabetical, leading to the bimap and its inverse

	var buf bytes.Buffer
	e := json.NewEncoder(&buf)
	d := jstream.NewDecoder(r, 0).ObjectAsKVS().MaxDepth(10)
	sset := set.NewStringSet()
	for mv := range d.Stream() {
		if mv.ValueType == jstream.Object {
			// This is a JSON object type (that preserves key order)
			kvs, ok := mv.Value.(jstream.KVS)
			if ok {
				for _, kv := range kvs {
					if sset.Contains(kv.Key) {

	case CounterMT:
		return "counter"
	case GaugeMT:
		return "gauge"
	case HistogramMT:
		return "histogram"
	default:
		return "*unknown*"
	}
}

func (mt MetricType) toProm() prometheus.ValueType {
	switch mt {
	case CounterMT:
		return prometheus.CounterValue
	case GaugeMT:
		return prometheus.GaugeValue
	case HistogramMT:
		return prometheus.CounterValue
	default: