SI-8627 make Stream.filterNot non-eager

The obvious fix, overriding `filterNot` in Stream, is not binary
compatible, see https://github.com/scala/scala/pull/3925

Instead, this makes `filterImpl` in TaversableLike private[scala],
which allows overriding it in Stream. The corresponding mima-failures
can be whitelisted, as the changes are only to private[scala].

In 2.12.x we can remove the override of `filter` in Stream, but in
2.11.x this is not binary compatible.

Eventually we'd also like to make filter / filterNot in
TraversableLike final, but that's not source compatible, so it cannot
be done in 2.12.x.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/library/scala/collection/TraversableLike.scala b/src/library/scala/collection/TraversableLike.scala
index d3a7db6968..a8731a51b1 100644
--- a/src/library/scala/collection/TraversableLike.scala
+++ b/src/library/scala/collection/TraversableLike.scala
@@ -253,7 +253,7 @@ trait TraversableLike[+A, +Repr] extends Any
     b.result
   }
 
-  private def filterImpl(p: A => Boolean, isFlipped: Boolean): Repr = {
+  private[scala] def filterImpl(p: A => Boolean, isFlipped: Boolean): Repr = {
     val b = newBuilder
     for (x <- this)
       if (p(x) != isFlipped) b += x