SI-9379 Added toString to .zipped to allow Stream etc to short-circuit

Tuple2Zipped and Tuple3Zipped would try to compute a hash code when .toString was called on them.  This overrides toString to print (collection1, collection2).zipped instead, using the collection's own toString method.  This allows collections that have a toString but not a hashCode (such as Iterator.from(0) and s = 1 #:: s) to print out as they usually do.

JUnit test to verify the deferral to collections' .toString.

1 files changed, 16 insertions, 0 deletions

diff --git a/test/junit/scala/collection/immutable/StreamTest.scala b/test/junit/scala/collection/immutable/StreamTest.scala
index fad4e502eb..1b257aabc4 100644
--- a/test/junit/scala/collection/immutable/StreamTest.scala
+++ b/test/junit/scala/collection/immutable/StreamTest.scala
@@ -107,4 +107,20 @@ class StreamTest {
   def withFilter_map_properly_lazy_in_tail: Unit = {
     assertStreamOpLazyInTail(_.withFilter(_ % 2 == 0).map(identity), List(1, 2))
   }
+
+  @Test
+  def test_si9379() {
+    class Boom {
+      private var i = -1
+      def inc = {
+        i += 1
+        if (i > 1000) throw new NoSuchElementException("Boom! Too many elements!")
+        i
+      }
+    }
+    val b = new Boom
+    val s = Stream.continually(b.inc)
+    // zipped.toString must allow s to short-circuit evaluation
+    assertTrue((s, s).zipped.toString contains s.toString)
+  }
 }