List<Range<C>> asRanges = ImmutableList.copyOf(rangeSet.asRanges());

    // test that connected ranges are coalesced
    for (int i = 0; i + 1 < asRanges.size(); i++) {
      Range<C> range1 = asRanges.get(i);
      Range<C> range2 = asRanges.get(i + 1);
      assertFalse(range1.isConnected(range2));
    }

    // test that there are no empty ranges
    for (Range<C> range : asRanges) {

  /**
   * Returns the range containing this key and its associated value, if such a range is present in
   * the range map, or {@code null} otherwise.
   */
  @CheckForNull
  Entry<Range<K>, V> getEntry(K key);

  /**
   * Returns the minimal range {@linkplain Range#encloses(Range) enclosing} the ranges in this
   * {@code RangeMap}.
   *
   * @throws NoSuchElementException if this range map is empty
   */
  Range<K> span();

  /**

  }

  @Override
  @CheckForNull
  public abstract Range<C> rangeContaining(C value);

  @Override
  public boolean isEmpty() {
    return asRanges().isEmpty();
  }

  @Override
  public void add(Range<C> range) {
    throw new UnsupportedOperationException();
  }

  @Override
  public void remove(Range<C> range) {
    throw new UnsupportedOperationException();
  }

  @Override

    List<Range<C>> asRanges = ImmutableList.copyOf(rangeSet.asRanges());

    // test that connected ranges are coalesced
    for (int i = 0; i + 1 < asRanges.size(); i++) {
      Range<C> range1 = asRanges.get(i);
      Range<C> range2 = asRanges.get(i + 1);
      assertFalse(range1.isConnected(range2));
    }

    // test that there are no empty ranges
    for (Range<C> range : asRanges) {