Fixes SI-5804.

The hash table initialSize method is now within
the the hashset and hashmap classes, and not in the companion.
Overriding this method now yields hashmaps and hashsets
of the proper initial capacity.

Review by @phaller.

src/library/scala/collection/mutable/FlatHashTable.scala

@@ -50,6 +50,10 @@ trait FlatHashTable[A] extends FlatHashTable.HashUtils[A] {
 
   protected def capacity(expectedSize: Int) = if (expectedSize == 0) 1 else powerOfTwo(expectedSize)
 
+  /** The initial size of the hash table.
+   */
+  def initialSize: Int = 32
+
   private def initialCapacity = capacity(initialSize)
 
   protected def randomSeed = seedGenerator.get.nextInt()
@@ -361,10 +365,6 @@ private[collection] object FlatHashTable {
   def defaultLoadFactor: Int = 450
   final def loadFactorDenum = 1000
 
-  /** The initial size of the hash table.
-   */
-  def initialSize: Int = 32
-
   def sizeForThreshold(size: Int, _loadFactor: Int) = math.max(32, (size.toLong * loadFactorDenum / _loadFactor).toInt)
 
   def newThreshold(_loadFactor: Int, size: Int) = {

src/library/scala/collection/mutable/HashTable.scala

@@ -56,7 +56,15 @@ trait HashTable[A, Entry >: Null <: HashEntry[A, Entry]] extends HashTable.HashU
 
   protected def tableSizeSeed = Integer.bitCount(table.length - 1)
 
-  protected def initialSize: Int = HashTable.initialSize
+  /** The initial size of the hash table.
+   */
+  protected def initialSize: Int = 16
+
+  /** The initial threshold.
+   */
+  private def initialThreshold(_loadFactor: Int): Int = newThreshold(_loadFactor, initialCapacity)
+
+  private def initialCapacity = capacity(initialSize)
 
   private def lastPopulatedIndex = {
     var idx = table.length - 1
@@ -354,16 +362,6 @@ private[collection] object HashTable {
   private[collection] final def defaultLoadFactor: Int = 750 // corresponds to 75%
   private[collection] final def loadFactorDenum = 1000;
 
-  /** The initial size of the hash table.
-   */
-  private[collection] final def initialSize: Int = 16
-
-  /** The initial threshold.
-   */
-  private[collection] final def initialThreshold(_loadFactor: Int): Int = newThreshold(_loadFactor, initialCapacity)
-
-  private[collection] final def initialCapacity = capacity(initialSize)
-
   private[collection] final def newThreshold(_loadFactor: Int, size: Int) = ((size.toLong * _loadFactor) / loadFactorDenum).toInt
 
   private[collection] final def sizeForThreshold(_loadFactor: Int, thr: Int) = ((thr.toLong * loadFactorDenum) / _loadFactor).toInt

test/files/run/t5804.check

@@ -0,0 +1,4 @@
+128
+16
+128
+32

test/files/run/t5804.scala

@@ -0,0 +1,32 @@
+
+
+import collection.mutable._
+
+
+object Test {
+
+  def main(args: Array[String]) {
+    class CustomHashMap extends HashMap[Int, Int] {
+      override def initialSize = 65
+
+      println(table.length)
+    }
+
+    new CustomHashMap
+    new HashMap {
+      println(table.length)
+    }
+
+    class CustomHashSet extends HashSet[Int] {
+      override def initialSize = 96
+
+      println(table.length)
+    }
+
+    new CustomHashSet
+    new HashSet {
+      println(table.length)
+    }
+  }
+
+}