Made the reading of y/n a little more robust.

2 files changed, 18 insertions, 11 deletions

diff --git a/src/compiler/scala/tools/nsc/interpreter/ILoop.scala b/src/compiler/scala/tools/nsc/interpreter/ILoop.scala
index d1a23f3bc5..b6a6da369f 100644
--- a/src/compiler/scala/tools/nsc/interpreter/ILoop.scala
+++ b/src/compiler/scala/tools/nsc/interpreter/ILoop.scala
@@ -198,6 +198,15 @@ class ILoop(in0: Option[BufferedReader], protected val out: PrintWriter)
   def plush(x: Any)   = { out print x ; out.flush() }
   def plushln(x: Any) = { out println x ; out.flush() }
 
+  private def echo(msg: String) = {
+    out println msg
+    out.flush()
+  }
+  private def echoNoNL(msg: String) = {
+    out print msg
+    out.flush()
+  }
+
   /** Search the history */
   def searchHistory(_cmdline: String) {
     val cmdline = _cmdline.toLowerCase
@@ -454,16 +463,13 @@ class ILoop(in0: Option[BufferedReader], protected val out: PrintWriter)
       }
       ex match {
         case _: NoSuchMethodError | _: NoClassDefFoundError =>
-          out.println("Unrecoverable error.")
+          echo("Unrecoverable error.")
           throw ex
         case _  =>
-          out.print(replayQuestionMessage)
-          out.flush()
-          if (in.readAssumingNo("")) {
-            out.println("\nAttempting session recovery with replay.")
-            replay()
-          }
-          else out.println("\nAbandoning crashed session.")
+          def fn(): Boolean = in.readYesOrNo(replayQuestionMessage, { echo("\nYou must enter y or n.") ; fn() })
+
+          if (fn()) replay()
+          else echo("\nAbandoning crashed session.")
       }
   }
 
diff --git a/src/compiler/scala/tools/nsc/interpreter/InteractiveReader.scala b/src/compiler/scala/tools/nsc/interpreter/InteractiveReader.scala
index 1430cbe55c..edade4da1b 100644
--- a/src/compiler/scala/tools/nsc/interpreter/InteractiveReader.scala
+++ b/src/compiler/scala/tools/nsc/interpreter/InteractiveReader.scala
@@ -27,12 +27,13 @@ trait InteractiveReader {
   def redrawLine(): Unit
   def currentLine: String
 
-  def readYesOrNo(prompt: String) = readOneKey(prompt) match {
+  def readYesOrNo(prompt: String, alt: => Boolean): Boolean = readOneKey(prompt) match {
     case 'y'  => true
     case 'n'  => false
+    case _    => alt
   }
-  def readAssumingNo(prompt: String)  = try readYesOrNo(prompt) catch { case _: MatchError  => false }
-  def readAssumingYes(prompt: String) = try readYesOrNo(prompt) catch { case _: MatchError  => true }
+  def readAssumingNo(prompt: String)  = readYesOrNo(prompt, false)
+  def readAssumingYes(prompt: String) = readYesOrNo(prompt, true)
 
   protected def readOneLine(prompt: String): String
   protected def readOneKey(prompt: String): Int