def toCsv()

in benchmarks/src/main/scala/org/apache/pekko/kafka/benchmarks/CsvFormatter.scala [50:117]
62 lines of code
15 McCabe index (conditional complexity)

  def toCsv(fields: immutable.Iterable[Any]): ByteString =
    if (fields.nonEmpty) nonEmptyToCsv(fields)
    else endOfLineBs

  private def nonEmptyToCsv(fields: immutable.Iterable[Any]) = {
    val builder = ByteString.createBuilder

    def splitAndDuplicateQuotesAndEscapes(field: String, splitAt: Int) = {

      @inline def indexOfQuoteOrEscape(lastIndex: Int) = {
        var index = lastIndex
        var found = -1
        while (index < field.length && found == -1) {
          val char = field(index)
          if (char == quoteChar || char == escapeChar) found = index
          index += 1
        }
        found
      }

      var lastIndex = 0
      var index = splitAt
      while (index > -1) {
        builder ++= ByteString.apply(field.substring(lastIndex, index), charsetName)
        val char = field.charAt(index)
        if (char == quoteChar) {
          builder ++= duplicatedQuote
        } else {
          builder ++= duplicatedEscape
        }
        lastIndex = index + 1
        index = indexOfQuoteOrEscape(lastIndex)
      }
      if (lastIndex < field.length) {
        builder ++= ByteString(field.substring(lastIndex), charsetName)
      }
    }

    def append(field: String) = {
      val (quoteIt, splitAt) = requiresQuotesOrSplit(field)
      if (quoteIt || quotingStyle == CsvQuotingStyle.Always) {
        builder ++= quoteBs
        if (splitAt != -1) {
          splitAndDuplicateQuotesAndEscapes(field, splitAt)
        } else {
          builder ++= ByteString(field, charsetName)
        }
        builder ++= quoteBs
      } else {
        builder ++= ByteString(field, charsetName)
      }
    }

    val iterator = fields.iterator
    var hasNext = iterator.hasNext
    while (hasNext) {
      val next = iterator.next()
      if (next != null) {
        append(next.toString)
      }
      hasNext = iterator.hasNext
      if (hasNext) {
        builder ++= delimiterBs
      }
    }
    builder ++= endOfLineBs
    builder.result()
  }