Tweak library

Author: som-snytt

library/src/scala/collection/concurrent/TrieMap.scala

@@ -314,9 +314,7 @@ private[collection] final class INode[K, V](bn: MainNode[K, V], g: Gen, equiv: E
     startgen: Gen,
     ct: TrieMap[K, V]): Option[V] = {
 
-    val m = GCAS_READ(ct) // use -Yinline!
-
-    m match {
+    GCAS_READ(ct) match {
       case cn: CNode[K, V] =>
         val idx = (hc >>> lev) & 0x1f
         val bmp = cn.bitmap
@@ -343,8 +341,8 @@ private[collection] final class INode[K, V](bn: MainNode[K, V], g: Gen, equiv: E
           if (res == None || (res eq null)) res
           else {
             @tailrec def cleanParent(nonlive: AnyRef): Unit = {
-              val pm = parent.GCAS_READ(ct)
-              pm match {
+              val cn = parent.GCAS_READ(ct)
+              cn match {
                 case cn: CNode[K, V] =>
                   val idx = (hc >>> (lev - 5)) & 0x1f
                   val bmp = cn.bitmap

library/src/scala/collection/convert/JavaCollectionWrappers.scala

@@ -456,22 +456,13 @@ private[collection] object JavaCollectionWrappers extends Serializable {
 
     def underlyingConcurrentMap: concurrent.Map[K, V] = underlying
 
-    override def putIfAbsent(k: K, v: V) = underlying.putIfAbsent(k, v) match {
-      case Some(v) => v
-      case None => null.asInstanceOf[V]
-    }
+    override def putIfAbsent(k: K, v: V) = underlying.putIfAbsent(k, v).getOrElse(null.asInstanceOf[V])
 
-    override def remove(k: AnyRef, v: AnyRef) = try {
-      underlying.remove(k.asInstanceOf[K], v.asInstanceOf[V])
-    } catch {
-      case ex: ClassCastException =>
-        false
-    }
+    override def remove(k: AnyRef, v: AnyRef) =
+      try underlying.remove(k.asInstanceOf[K], v.asInstanceOf[V])
+      catch { case ex: ClassCastException => false }
 
-    override def replace(k: K, v: V): V = underlying.replace(k, v) match {
-      case Some(v) => v
-      case None => null.asInstanceOf[V]
-    }
+    override def replace(k: K, v: V): V = underlying.replace(k, v).getOrElse(null.asInstanceOf[V])
 
     override def replace(k: K, oldval: V, newval: V) = underlying.replace(k, oldval, newval)
   }

library/src/scala/collection/immutable/RedBlackTree.scala

@@ -31,8 +31,8 @@ private[collection] object RedBlackTree {
 
   def contains[A: Ordering](tree: Tree[A, _], x: A): Boolean = lookup(tree, x) ne null
   def get[A: Ordering, B](tree: Tree[A, B], x: A): Option[B] = lookup(tree, x) match {
-    case null => None
-    case tree => Some(tree.value)
+    case null  => None
+    case found => Some(found.value)
   }
 
   @tailrec