Benchmark to check the execution time of takeWhile using local state and local immutable structure

TakeWhileBenchmark.scala

class TakeWhileBenchmark {

  def takeWhile1[A](list: List[A])(f: A => Boolean): List[A]= {
    @tailrec
    def go(list: List[A], acc: List[A]): List[A] = {
      list match {
        case x :: xs if f(x) => go(xs, x :: acc)
        case _ => acc
      }
    }
    go(list, List()).reverse
  }

  def takeWhile2[A](list: List[A])(p: A => Boolean): List[A] = {
    val b = new ListBuffer[A]
    var these = list
    while (!these.isEmpty && p(these.head)) {
      b += these.head
      these = these.tail
    }
    b.toList
  }

  def benchLocalState(limit: Int) {
    val input = (1 to 100000).toList
    val time = 1 to 10000
    val start = System.currentTimeMillis()
    time.foreach {
      _ => takeWhile2(input)(_ <= limit)
    }
    val stop = System.currentTimeMillis()
    print(s"duration: ${ stop - start }")
  }

  def benchNoState(limit: Int) {
    val input = (1 to 100000).toList
    val time = 1 to 10000
    val start = System.currentTimeMillis()
    time.foreach {
      _ => takeWhile1(input)(_ <= limit)
    }
    val stop = System.currentTimeMillis()
    print(s"duration: ${ stop - start }")
  }

}