Tuple2.zipped not lazy enough for Streams

[scabug]

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scala> val fib: Stream[Int] = 1 #:: 1 #:: fib.zip(fib.tail).map { case (a,b) => a + b }
fib: Stream[Int] = Stream(1, ?)

scala> fib take 10 toList
res1: List[Int] = List(1, 1, 2, 3, 5, 8, 13, 21, 34, 55)

scala> val fib: Stream[Int] = 1 #:: 1 #:: (fib, fib.tail).zipped.map(_ + _)
fib: Stream[Int] = Stream(1, ?)

scala> fib take 10 toList
java.lang.StackOverflowError
        at scala.collection.mutable.LazyBuilder.<init>(LazyBuilder.scala:23)
        at scala.collection.immutable.Stream$$StreamBuilder.<init>(Stream.scala:427)
        at scala.collection.immutable.Stream$$.newBuilder(Stream.scala:418)
        at scala.collection.generic.GenericTraversableTemplate$$class.genericBuilder(GenericTraversableTemplate.scala:34)
        at scala.collection.immutable.Stream.genericBuilder(Stream.scala:41)
        at scala.collection.generic.TraversableFactory$$GenericCanBuildFrom.apply(TraversableFactory.scala:22)
        at scala.collection.generic.TraversableFactory$$GenericCanBuildFrom.apply(TraversableFactory.scala:21)
        at scala.Tuple2$$Zipped.map(Tuple2.scala:54)
        at $$anonfun$$1$$$$anonfun$$apply$$1.apply(<console>:4)
        at $$anonfun$$1$$$$anonfun$$apply$$1.apply(<console>:4)
        at scala.collection.immutable.Stream$$Cons.tail(Stream.scala:489)
        at scala.collection.immutable.Stream$$Cons.tail(Stream.scala:483)
        at scala.collection.LinearSeqLike$$$$anon$$1.next(LinearSeqLike.scala:72)
        at scala.Tuple2$$Zipped$$$$anonfun$$map$$1.apply(Tuple2.scala:59)
        at scala.collection.immutable.Stream.foreach(Stream.scala:191)
        at scala.Tuple2$$Zipped.map(Tuple2.scala:57)
        at $$anonfun$$1$$$$anonfun$$apply$$1.apply(<console>:4)
        at $$anonfun$$1$$$$anonfun$$apply$$1.apply(<console>:4)
        at scala.collection.immutable.Stream$$Cons.tail(Stream.scala:489)
        at scala.collection.immutable.Stream$$Cons.tail(Stream.scala:483)
        at scala.collection.LinearSeqLike$$$$anon$$1.next(LinearSeqLike.scala:72)
        at scala.Tuple2$$Zipped$$$$anonfun$$map$$1.apply(Tuple2.scala:59)
        at scala.collection.immutable.Stream.foreach(Stream.scala:191)
        at scala.Tuple2$$Zipped.map(Tuple2.scala:57)
        at $$anonfun$$1$$$$anonfun$$apply$$1.apply(<console>:4)
        at $$anonfun$$1$$$$anonfun$$apply$$1.apply(<console>:4)
        at scala.collection.immutable.Stream$$Cons.tail(Stream.scala:489)
        at scala.collection.immutable.Stream$$Cons.tail(Stream.scala:483)
        at scala.collection.LinearSeqLike$$$$anon$$1.next(LinearSeqLike.scala:72)
        at scala.Tuple2$$Zipped$$$$anonfun$$map$$1.apply(Tuple2.scala:59)
        at scala.collection.immutable.Stream.foreach(Stream.scala:191)
        at scala.Tuple2$$Zipped.map(Tuple2.scala:57)
        at $$anonfun$$1$$$$anonfun$$apply$$1.apply(<console>:4)
        at $$anonfun$$1$$$$anonfun$$apply$$1.apply(<console>:4)
        at scala.collection.immutable.Stream$$Cons.tail(Stream.scala:489)
        at scala.collection.immutable.Stream$$Cons.tail(Stream.scala:483)
        at scala.collection.LinearSeqLike$$$$anon$$1.next(Linea...

[scabug]

Imported From: https://issues.scala-lang.org/browse/SI-2634?orig=1
Reporter: @szeiger

[scabug]

@adriaanm said:
Sorry, we'll have to spec zipped as returning a strict collection, because the lazy variant is too complicated to implement with the current interface for Builder. Or are we missing something? Will be a wontfix as soon as I get a chance to update the documentation to reflect this.

[scabug]

@adriaanm said:
(In r20998) see #2634: updated docs to indicate zipped is strict

[SethTisue]

wontfix until 2.13, then willfix? design discussion at scala/collection-strawman#223