static LongLongMap noop() {
    return new ParallelWrites() {
      @Override
      public Writer newWriter() {
        return (key, value) -> {
        };
      }

      @Override
      public long get(long key) {
        throw new UnsupportedOperationException("get");
      }

      @Override
      public long diskUsageBytes() {
        return 0;
      }

      @Override
      public void close() {}
    };
  }
Returns a longlong map that stores no data and throws on read
planetiler-core/src/main/java/com/onthegomap/planetiler/collection/LongLongMap.java