sbt/main/command/ExceptionCategory.scala

package sbt

	import java.lang.reflect.InvocationTargetException
	import scala.annotation.tailrec

private[sbt] sealed abstract class ExceptionCategory {
	def isFull: Boolean = false
}
private[sbt] object ExceptionCategory {

	@tailrec def apply(t: Throwable): ExceptionCategory = t match {
		case _: AlreadyHandledException | _: UnprintableException => AlreadyHandled
		case ite: InvocationTargetException =>
			val cause = ite.getCause
			if(cause == null || cause == ite) new Full(ite) else apply(cause)
		case _: MessageOnlyException => new MessageOnly(t.toString)
		case _ => new Full(t)
	}

	object AlreadyHandled extends ExceptionCategory
	final class MessageOnly(val message: String) extends ExceptionCategory
	final class Full(val exception: Throwable) extends ExceptionCategory {
		override def isFull = true
	}
}