Does what can probably be done about strange it...

Does what can probably be done about strange iterator exhaustion
behavior. Maybe we should start thinking about iteratees... Closes
#3760, no review.

1 files changed, 9 insertions, 1 deletions

diff --git a/src/library/scala/collection/LinearSeqLike.scala b/src/library/scala/collection/LinearSeqLike.scala
index c2c4996f47..8bf45348db 100644
--- a/src/library/scala/collection/LinearSeqLike.scala
+++ b/src/library/scala/collection/LinearSeqLike.scala
@@ -56,6 +56,14 @@ trait LinearSeqLike[+A, +Repr <: LinearSeqLike[A, Repr]] extends SeqLike[A, Repr
       if (hasNext) {
         val result = these.head; these = these.tail; result
       } else Iterator.empty.next
-    override def toList: List[A] = these.toList
+
+    /** Have to clear these so the iterator is exhausted like
+     *  it would be without the optimization.
+     */
+    override def toList: List[A] = {
+      val xs = these.toList
+      these = newBuilder.result
+      xs
+    }
   }
 }