Fixed an issue with ListSet getting confused ab...

Fixed an issue with ListSet getting confused about what goes forward and
what goes backward. No review.

1 files changed, 6 insertions, 0 deletions

diff --git a/test/files/run/bug3822.scala b/test/files/run/bug3822.scala
index 7401ecbde2..c35804035e 100644
--- a/test/files/run/bug3822.scala
+++ b/test/files/run/bug3822.scala
@@ -7,6 +7,12 @@ object Test {
 
     assert(xs.size == 200002)
     assert(xs.sum == 100001)
+
+    val ys = ListSet[Int]()
+    val ys1 = (1 to 12).grouped(3).foldLeft(ys)(_ ++ _)
+    val ys2 = (1 to 12).foldLeft(ys)(_ + _)
+
+    assert(ys1 == ys2)
   }
 }