A little debugging infrastructure for sys.process.

1 files changed, 43 insertions, 20 deletions

diff --git a/src/library/scala/sys/process/package.scala b/src/library/scala/sys/process/package.scala
index 0185b1a8f0..9421bff88d 100644
--- a/src/library/scala/sys/process/package.scala
+++ b/src/library/scala/sys/process/package.scala
@@ -6,29 +6,52 @@
 **                          |/                                          **
 \*                                                                      */
 
-package scala.sys
+// Developer note:
+//   scala -J-Dscala.process.debug
+// for process debugging output.
+//
+package scala.sys {
+  package object process extends ProcessImplicits {
+    def javaVmArguments: List[String] = {
+      import collection.JavaConversions._
 
-package object process extends ProcessImplicits {
-  // These are in a nested object instead of at the package level
-  // due to the issues described in tickets #3160 and #3836.
-  private[process] object processInternal {
-    type =?>[-A, +B]     = PartialFunction[A, B]
-    type Closeable       = java.io.Closeable
-    type File            = java.io.File
-    type IOException     = java.io.IOException
-    type InputStream     = java.io.InputStream
-    type JProcess        = java.lang.Process
-    type JProcessBuilder = java.lang.ProcessBuilder
-    type OutputStream    = java.io.OutputStream
-    type SyncVar[T]      = scala.concurrent.SyncVar[T]
-    type URL             = java.net.URL
-
-    def onInterrupt[T](handler: => T): Throwable =?> T = {
-      case _: InterruptedException => handler
+      java.lang.management.ManagementFactory.getRuntimeMXBean().getInputArguments().toList
     }
+  }
+  // private val shell: String => Array[String] =
+  //   if (isWin) Array("cmd.exe", "/C", _)
+  //   else Array("sh", "-c", _)
+
+  package process {
+    // These are in a nested object instead of at the package level
+    // due to the issues described in tickets #3160 and #3836.
+    private[process] object processInternal {
+      final val processDebug = props contains "scala.process.debug"
+      // final val processDebug = true
+      dbg("Initializing process package.")
+
+      type =?>[-A, +B]     = PartialFunction[A, B]
+      type Closeable       = java.io.Closeable
+      type File            = java.io.File
+      type IOException     = java.io.IOException
+      type InputStream     = java.io.InputStream
+      type JProcess        = java.lang.Process
+      type JProcessBuilder = java.lang.ProcessBuilder
+      type OutputStream    = java.io.OutputStream
+      type SyncVar[T]      = scala.concurrent.SyncVar[T]
+      type URL             = java.net.URL
+
+      def onInterrupt[T](handler: => T): Throwable =?> T = {
+        case _: InterruptedException => handler
+      }
+
+      def ioFailure[T](handler: IOException => T): Throwable =?> T = {
+        case e: IOException => handler(e)
+      }
 
-    def ioFailure[T](handler: IOException => T): Throwable =?> T = {
-      case e: IOException => handler(e)
+      def dbg(msgs: Any*) = if (processDebug) {
+        Console.println("[process] " + (msgs mkString " "))
+      }
     }
   }
 }