fixup! fixup! Backport LazyList

fix LazyListTest

Author: NthPortal

compat/src/main/scala-2.11_2.12/scala/collection/compat/immutable/LazyList.scala

@@ -1180,6 +1180,7 @@ object LazyList extends SeqFactory[LazyList] {
     /** Construct a LazyList consisting of a given first element followed by elements
      *  from another LazyList.
      */
+    // def #::[B >: A](elem: => B): LazyList[B] = newLL(sCons(elem, l()))
     def #::[B >: A](elem: B): LazyList[B] = newLL(sCons(elem, l()))
 
     /** Construct a LazyList consisting of the concatenation of the given LazyList and

compat/src/test/scala/test/scala/collection/LazyListTest.scala

@@ -52,13 +52,14 @@ class LazyListTest {
     assertEquals(LazyList(None, Some(1)), LazyList(None) #::: LazyList(Some(1)))
   }
 
-  @Test
-  def testLazyListDoesNotForceHead: Unit = {
+   @Test
+   def testLazyListDoesNotForceHead: Unit = {
     var i = 0
     def f: Int = { i += 1; i }
-    val s = LazyList.empty.#::(f).#::(f).#::(f)
+    // val s = LazyList.empty.#::(f).#::(f).#::(f)
+    val s = LazyList.empty.#::(f).#::(f).#::(f).#:::(LazyList.empty)
     assertEquals(0, i)
-  }
+   }
 
   @Test
   def testEmptyLazyListToString(): Unit = {
@@ -214,7 +215,8 @@ class LazyListTest {
 
     var lazeCount = 0
     def lazeL(i: Int) = { lazeCount += 1; i }
-    val xs21 = lazeL(1) #:: lazeL(2) #:: lazeL(3) #:: LazyList.empty
+    // val xs21 = lazeL(1) #:: lazeL(2) #:: lazeL(3) #:: LazyList.empty
+    val xs21 = LazyList.empty #::: lazeL(1) #:: lazeL(2) #:: lazeL(3) #:: LazyList.empty
 
     assertEquals(0, lazeCount)
   }