1 files changed, 59 insertions, 0 deletions
diff --git a/src/compiler/scala/tools/cmd/program/Scmp.scala b/src/compiler/scala/tools/cmd/program/Scmp.scala
new file mode 100644
index 0000000000..ff4fa11eaf
--- /dev/null
+++ b/src/compiler/scala/tools/cmd/program/Scmp.scala
@@ -0,0 +1,59 @@
+/* NEST (New Scala Test)
+ * Copyright 2007-2010 LAMP/EPFL
+ * @author  Paul Phillips
+ */
+
+package scala.tools
+package cmd
+package program
+
+import nsc.io._
+
+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 output = Process(cmd, redirect = true).slurp()
+
+      returning(File.makeTemp())(_ writeAll output)
+    }
+
+    val cmds = List(p1args, p2args) map createCmd
+    println(cmds.mkString("Running command lines:\n  ", "\n  ", ""))
+
+    val files = cmds map runCmd map (_.path)
+    val diff = Process("diff %s %s".format(files: _*)).slurp()
+
+    if (diff.isEmpty) println("No differences.")
+    else println(diff)
+  }
+}