code: function concatBulkString (parser) {
    const list = parser.bufferCache
    const oldOffset = parser.offset
    var chunks = list.length
    var offset = parser.bigStrSize - parser.totalChunkSize
    parser.offset = offset
    if (offset <= 2) {
      if (chunks === 2) {
        return list[0].toString('utf8', oldOffset, list[0].length + offset - 2)
      }
      chunks--
      offset = list[list.length - 2].length + offset
    }
    var res = decoder.write(list[0].slice(oldOffset))
    for (var i = 1; i < chunks - 1; i++) {
      res += decoder.write(list[i])
    }
    res += decoder.end(list[i].slice(0, offset - 2))
    return res
  }
docs: Concat a bulk string containing multiple chunks
  
  Notes:
  1) The first chunk might contain the whole bulk string including the \r
  2) We are only safe to fully add up elements that are neither the first nor any of the last two elements
  
  @param {JavascriptRedisParser} parser
  @returns {String}