public ColorBuffer append(ColorBuffer buf) {
    parts.addAll(buf.parts);
    visibleLength += buf.getVisibleLength();
    return this;
  }
Truncate the ColorBuffer to the specified length and return
the new ColorBuffer. Any open color tags will be closed.
Do nothing if the specified length is <= 0.
beeline/src/java/org/apache/hive/beeline/ColorBuffer.java