Custom sbt task to run an application many times

runMany.sbt

// Custom task to run an application many times.
// Add scriptlet into build.sbt
lazy val runMany = inputKey[Unit]("Running the app many times. Provide nr of times. Defaults to 10.")

runMany in Runtime := {
  val args: Seq[String] = Def.spaceDelimited("Number of times to run. Default is: 10.").parsed
  val times = Try {
    args.head.toInt
  }.getOrElse(10)
  println(s"Running $times times...")

  val myMain: Option[String] = (selectMainClass in Runtime).value
  val myRunner: ScalaRun = (runner in Runtime).value
  val fcp: Seq[Attributed[File]] = (fullClasspath in Runtime).value

  myMain match {
    case Some(mainclass) =>
      println("Warming up...")
      for (i <- 1 to times) {
        print(i)
        myRunner.run(mainclass, Attributed.data(fcp), Seq.empty[String], streams.value.log)
      }
      println("Done.")
    case None =>
      println("No main class selected.")
  }

  println("Done!")
}