Add lazyAppendAll alias to append in Stream

Author: julienrf

src/main/scala-2.12/collection/compat/package.scala

@@ -41,6 +41,10 @@ package object compat {
     def fromSpecific(source: TraversableOnce[Int]): C = fact.apply(source.toSeq: _*)
   }
 
+  implicit class StreamExtensionMethods[A](private val stream: Stream[A]) extends AnyVal {
+    def lazyAppendAll(as: => TraversableOnce[A]): Stream[A] = stream.append(as)
+  }
+
   // This really belongs into scala.collection but there's already a package object in scala-library so we can't add to it
   type IterableOnce[+X] = TraversableOnce[X]
 }

src/test/scala/collection/StreamTest.scala

@@ -0,0 +1,15 @@
+package collection
+
+import org.junit.Test
+
+import scala.collection.compat._
+
+class StreamTest {
+
+  @Test
+  def lazyAppendAll(): Unit = {
+    val s = 1 #:: 2 #:: 3 #:: Stream.Empty
+    s.lazyAppendAll(List(4, 5, 6))
+  }
+
+}