Some new tools for the tools directory.

amounts to a yak shaving expedition to enable this, which now works:

  tools/diffPickled scala.Either

and since stability is presently broken you will see the following.
(When it's not broken you will see nothing.)

  541,544c541,544
  < 538,4090: EXTref 3: 539(Left) 2
  < 539,4095: TYPEname 4: Left
  < 540,4101: EXTref 3: 541(Right) 2
  < 541,4106: TYPEname 5: Right
  ---
  > 538,4090: EXTref 3: 539(Right) 2
  > 539,4095: TYPEname 5: Right
  > 540,4102: EXTref 3: 541(Left) 2
  > 541,4107: TYPEname 4: Left

2 files changed, 12 insertions, 1 deletions

diff --git a/src/scalap/scala/tools/scalap/Classfile.scala b/src/scalap/scala/tools/scalap/Classfile.scala
index 44f687bd85..c4f273c5aa 100644
--- a/src/scalap/scala/tools/scalap/Classfile.scala
+++ b/src/scalap/scala/tools/scalap/Classfile.scala
@@ -26,6 +26,7 @@ class Classfile(in: ByteArrayReader) {
   val fields = readMembers(true)
   val methods = readMembers(false)
   val attribs = readAttribs
+  def scalaSigAttribute = attribs find (_.toString == Main.SCALA_SIG)
 
   def readAttribs = {
     val n = in.nextChar
diff --git a/src/scalap/scala/tools/scalap/Decode.scala b/src/scalap/scala/tools/scalap/Decode.scala
index 04d72c015b..6e55558249 100644
--- a/src/scalap/scala/tools/scalap/Decode.scala
+++ b/src/scalap/scala/tools/scalap/Decode.scala
@@ -10,7 +10,8 @@
 package scala.tools.scalap
 
 import scala.tools.scalap.scalax.rules.scalasig._
-import scala.tools.nsc.util.ScalaClassLoader.getSystemLoader
+import scala.tools.nsc.util.ScalaClassLoader.{ getSystemLoader, findBytesForClassName }
+import Main.SCALA_SIG
 
 /** Temporary decoder.  This would be better off in the scala.tools.nsc
  *  but right now the compiler won't acknowledge scala.tools.scalap
@@ -23,6 +24,15 @@ object Decode {
     case _                      => NoSymbol
   }
 
+  /** Return the classfile bytes representing the scala sig attribute.
+   */
+  def scalaSigBytes(name: String): Option[Array[Byte]] = {
+    val bytes = findBytesForClassName(name)
+    val reader = new ByteArrayReader(bytes)
+    val cf = new Classfile(reader)
+    cf.scalaSigAttribute map (_.data)
+  }
+
   /** private[scala] so nobody gets the idea this is a supported interface.
    */
   private[scala] def caseParamNames(path: String): Option[List[String]] = {