Make Iterator.toStream be properly lazy.

1 files changed, 13 insertions, 0 deletions

diff --git a/test/files/run/bug3516.scala b/test/files/run/bug3516.scala
new file mode 100644
index 0000000000..aa302ce85a
--- /dev/null
+++ b/test/files/run/bug3516.scala
@@ -0,0 +1,13 @@
+object Test {
+  def mkIterator = (1 to 5).iterator map (x => { println(x) ; x })
+  def mkInfinite = Iterator continually { println(1) ; 1 }
+
+  def main(args: Array[String]): Unit = {
+    // Stream is strict in its head so we should see 1 from each of them.
+    val s1 = mkIterator.toStream
+    val s2 = mkInfinite.toStream
+    // back and forth without slipping into nontermination.
+    println((Stream from 1).toIterator.drop(10).toStream.drop(10).toIterator.next)
+    ()
+  }
+}