Scala example source code file (Scmp.scala)

This example Scala source code file (Scmp.scala) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Scala tags/keywords

array, list, list, nil, no, no, running, scmp, scmpspec, scmpspec, simple, string, string, unit

The Scala Scmp.scala source code

/* NEST (New Scala Test)
 * Copyright 2007-2011 LAMP/EPFL
 * @author  Paul Phillips
 */

package scala.tools
package cmd
package program

import nsc.io._
import scala.sys.process._

object Scmp {
  private val scmpUsage = """
    |Usage: scmp [options] <cmd line>
    |Example: scmp --p1 '-no-specialization -Ydebug' scalac src/library/scala/Function1.scala
    |
    |Note: the command line must start with a path to scalac.
    |""".stripMargin
  private val scmpOptions = List(
    "p1" -> "options for the first run only",
    "p2" -> "options for the second run only"
  )
  private val scmpInfo = Simple.scalaProgramInfo("scmp", scmpUsage)
  lazy val ScmpSpec = Simple(scmpInfo, Nil, scmpOptions, x => returning(x)(_.onlyKnownOptions = false))
  
  def main(args0: Array[String]): Unit = {
    if (args0.isEmpty)
      return println(scmpUsage)
      
    val runner = ScmpSpec instance args0
    import runner._
    
    val p1args = parsed.getOrElse("--p1", "")
    val p2args = parsed.getOrElse("--p2", "")
    
    if (p1args.isEmpty && p2args.isEmpty)
      return println("At least one of --p1 and --p2 must be given.")
    if (residualArgs.isEmpty)
      return println("There is no command to run.")
    
    def createCmd(extras: String) =
      fromArgs(residualArgs.patch(1, toArgs(extras), 0))

    def runCmd(cmd: String) = {
      val tmpfile = File.makeTemp()
      (cmd #> tmpfile.jfile !)
      tmpfile
    }

    val cmds = List(p1args, p2args) map createCmd
    println(cmds.mkString("Running command lines:\n  ", "\n  ", ""))
    
    val files = cmds map runCmd map (_.path)
    val diff = "diff %s %s".format(files: _*).!!
    
    if (diff.isEmpty) println("No differences.")
    else println(diff)
  }
}