code: private static <K extends Comparable, V> Range<K> coalesce(
        Range<K> range, V value, @NullableDecl Entry<Cut<K>, RangeMapEntry<K, V>> entry) {
      if (entry != null
          && entry.getValue().getKey().isConnected(range)
          && entry.getValue().getValue().equals(value)) {
        return range.span(entry.getValue().getKey());
      }
      return range;
    }
docs: Returns the range that spans the given range and entry, if the entry can be coalesced.