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, 9 insertions, 0 deletions

diff --git a/bincompat-backward.whitelist.conf b/bincompat-backward.whitelist.conf
index ffacbf0442..1c48887b63 100644
--- a/bincompat-backward.whitelist.conf
+++ b/bincompat-backward.whitelist.conf
@@ -185,6 +185,15 @@ filter {
     {
         matchName="scala.reflect.runtime.SynchronizedOps.newNestedScope"
         problemName=MissingMethodProblem
+    },
+    // see github.com/scala/scala/pull/3925, SI-8627, SI-6440
+    {
+        matchName="scala.collection.TraversableLike.filterImpl"
+        problemName=MissingMethodProblem
+    },
+    {
+        matchName="scala.collection.immutable.Stream.filteredTail"
+        problemName=MissingMethodProblem
     }
   ]
 }