Port scala/scala#10437 to scala2-library-cc

scala2-library-cc/src/scala/collection/convert/JavaCollectionWrappers.scala

@@ -39,13 +39,13 @@ private[collection] object JavaCollectionWrappers extends Serializable {
   }
 
   @SerialVersionUID(3L)
-  class JIteratorWrapper[A](val underlying: ju.Iterator[A]) extends AbstractIterator[A] with Iterator[A] with Serializable {
+  class JIteratorWrapper[A](val underlying: ju.Iterator[A]) extends AbstractIterator[A] with Serializable {
     def hasNext = underlying.hasNext
     def next() = underlying.next
   }
 
   @SerialVersionUID(3L)
-  class JEnumerationWrapper[A](val underlying: ju.Enumeration[A]) extends AbstractIterator[A] with Iterator[A] with Serializable {
+  class JEnumerationWrapper[A](val underlying: ju.Enumeration[A]) extends AbstractIterator[A] with Serializable {
     def hasNext = underlying.hasMoreElements
     def next() = underlying.nextElement
   }

scala2-library-cc/src/scala/collection/immutable/ChampCommon.scala

@@ -13,6 +13,7 @@
 package scala.collection.immutable
 
 
+import scala.collection.AbstractIterator
 import java.lang.Integer.bitCount
 import java.lang.Math.ceil
 import java.lang.System.arraycopy
@@ -105,7 +106,7 @@ private[collection] abstract class Node[T <: Node[T]] {
   *
   * @tparam T the trie node type we are iterating over
   */
-private[immutable] abstract class ChampBaseIterator[T <: Node[T]] {
+private[immutable] abstract class ChampBaseIterator[A, T <: Node[T]] extends AbstractIterator[A] {
 
   import Node.MaxDepth
 
@@ -192,7 +193,7 @@ private[immutable] abstract class ChampBaseIterator[T <: Node[T]] {
   *
   * @tparam T the trie node type we are iterating over
   */
-private[immutable] abstract class ChampBaseReverseIterator[T <: Node[T]] {
+private[immutable] abstract class ChampBaseReverseIterator[A, T <: Node[T]] extends AbstractIterator[A] {
 
   import Node.MaxDepth
 

scala2-library-cc/src/scala/collection/immutable/HashMap.scala

@@ -699,12 +699,12 @@ private final class BitmapIndexedMapNode[K, +V](
     if ((dataMap & bitpos) != 0) {
       val index = indexFrom(dataMap, mask, bitpos)
       val payload = getPayload(index)
-      if (key == payload._1) payload else throw new NoSuchElementException
+      if (key == payload._1) payload else Iterator.empty.next()
     } else if ((nodeMap & bitpos) != 0) {
       val index = indexFrom(nodeMap, mask, bitpos)
       getNode(index).getTuple(key, originalHash, hash, shift + BitPartitionSize)
     } else {
-      throw new NoSuchElementException
+      Iterator.empty.next()
     }
   }
 
@@ -1873,7 +1873,7 @@ private final class HashCollisionMapNode[K, +V ](
 
   def size: Int = content.length
 
-  def apply(key: K, originalHash: Int, hash: Int, shift: Int): V = get(key, originalHash, hash, shift).getOrElse(throw new NoSuchElementException)
+  def apply(key: K, originalHash: Int, hash: Int, shift: Int): V = get(key, originalHash, hash, shift).getOrElse(Iterator.empty.next())
 
   def get(key: K, originalHash: Int, hash: Int, shift: Int): Option[V] =
     if (this.hash == hash) {
@@ -1883,7 +1883,7 @@ private final class HashCollisionMapNode[K, +V ](
 
   override def getTuple(key: K, originalHash: Int, hash: Int, shift: Int): (K, V) = {
     val index = indexOf(key)
-    if (index >= 0) content(index) else throw new NoSuchElementException
+    if (index >= 0) content(index) else Iterator.empty.next()
   }
 
   def getOrElse[V1 >: V](key: K, originalHash: Int, hash: Int, shift: Int, f: => V1): V1 = {
@@ -2096,11 +2096,10 @@ private final class HashCollisionMapNode[K, +V ](
 }
 
 private final class MapKeyIterator[K, V](rootNode: MapNode[K, V])
-  extends ChampBaseIterator[MapNode[K, V]](rootNode) with Iterator[K] {
+  extends ChampBaseIterator[K, MapNode[K, V]](rootNode) {
 
   def next() = {
-    if (!hasNext)
-      throw new NoSuchElementException
+    if (!hasNext) Iterator.empty.next()
 
     val key = currentValueNode.getKey(currentValueCursor)
     currentValueCursor += 1
@@ -2111,11 +2110,10 @@ private final class MapKeyIterator[K, V](rootNode: MapNode[K, V])
 }
 
 private final class MapValueIterator[K, V](rootNode: MapNode[K, V])
-  extends ChampBaseIterator[MapNode[K, V]](rootNode) with Iterator[V] {
+  extends ChampBaseIterator[V, MapNode[K, V]](rootNode) {
 
   def next() = {
-    if (!hasNext)
-      throw new NoSuchElementException
+    if (!hasNext) Iterator.empty.next()
 
     val value = currentValueNode.getValue(currentValueCursor)
     currentValueCursor += 1
@@ -2125,11 +2123,10 @@ private final class MapValueIterator[K, V](rootNode: MapNode[K, V])
 }
 
 private final class MapKeyValueTupleIterator[K, V](rootNode: MapNode[K, V])
-  extends ChampBaseIterator[MapNode[K, V]](rootNode) with Iterator[(K, V)] {
+  extends ChampBaseIterator[(K, V), MapNode[K, V]](rootNode) {
 
   def next() = {
-    if (!hasNext)
-      throw new NoSuchElementException
+    if (!hasNext) Iterator.empty.next()
 
     val payload = currentValueNode.getPayload(currentValueCursor)
     currentValueCursor += 1
@@ -2140,11 +2137,10 @@ private final class MapKeyValueTupleIterator[K, V](rootNode: MapNode[K, V])
 }
 
 private final class MapKeyValueTupleReverseIterator[K, V](rootNode: MapNode[K, V])
-  extends ChampBaseReverseIterator[MapNode[K, V]](rootNode) with Iterator[(K, V)] {
+  extends ChampBaseReverseIterator[(K, V), MapNode[K, V]](rootNode) {
 
   def next() = {
-    if (!hasNext)
-      throw new NoSuchElementException
+    if (!hasNext) Iterator.empty.next()
 
     val payload = currentValueNode.getPayload(currentValueCursor)
     currentValueCursor -= 1
@@ -2154,13 +2150,12 @@ private final class MapKeyValueTupleReverseIterator[K, V](rootNode: MapNode[K, V
 }
 
 private final class MapKeyValueTupleHashIterator[K, V](rootNode: MapNode[K, V])
-  extends ChampBaseReverseIterator[MapNode[K, V]](rootNode) with Iterator[Any] {
+  extends ChampBaseReverseIterator[Any, MapNode[K, V]](rootNode) {
   private[this] var hash = 0
   private[this] var value: V = _
   override def hashCode(): Int = MurmurHash3.tuple2Hash(hash, value.##, MurmurHash3.productSeed)
   def next() = {
-    if (!hasNext)
-      throw new NoSuchElementException
+    if (!hasNext) Iterator.empty.next()
 
     hash = currentValueNode.getHash(currentValueCursor)
     value = currentValueNode.getValue(currentValueCursor)
@@ -2170,7 +2165,7 @@ private final class MapKeyValueTupleHashIterator[K, V](rootNode: MapNode[K, V])
 }
 
 /** Used in HashMap[K, V]#removeAll(HashSet[K]) */
-private final class MapNodeRemoveAllSetNodeIterator[K](rootSetNode: SetNode[K]) extends ChampBaseIterator(rootSetNode) {
+private final class MapNodeRemoveAllSetNodeIterator[K](rootSetNode: SetNode[K]) extends ChampBaseIterator[K, SetNode[K]](rootSetNode) {
   /** Returns the result of immutably removing all keys in `rootSetNode` from `rootMapNode` */
   def removeAll[V](rootMapNode: BitmapIndexedMapNode[K, V]): BitmapIndexedMapNode[K, V] = {
     var curr = rootMapNode
@@ -2186,6 +2181,8 @@ private final class MapNodeRemoveAllSetNodeIterator[K](rootSetNode: SetNode[K])
     }
     curr
   }
+
+  override def next() = Iterator.empty.next()
 }
 
 /**
@@ -2371,7 +2368,7 @@ private[immutable] final class HashMapBuilder[K, V] extends ReusableBuilder[(K,
     ensureUnaliased()
     xs match {
       case hm: HashMap[K, V] =>
-        new ChampBaseIterator[MapNode[K, V]](hm.rootNode) {
+        new ChampBaseIterator[(K, V), MapNode[K, V]](hm.rootNode) {
           while(hasNext) {
             val originalHash = currentValueNode.getHash(currentValueCursor)
             update(
@@ -2384,6 +2381,8 @@ private[immutable] final class HashMapBuilder[K, V] extends ReusableBuilder[(K,
             )
             currentValueCursor += 1
           }
+
+          override def next() = Iterator.empty.next()
         }
       case hm: collection.mutable.HashMap[K, V] =>
         val iter = hm.nodeIterator

scala2-library-cc/src/scala/collection/immutable/HashSet.scala

@@ -1884,11 +1884,10 @@ private final class HashCollisionSetNode[A](val originalHash: Int, val hash: Int
 }
 
 private final class SetIterator[A](rootNode: SetNode[A])
-  extends ChampBaseIterator[SetNode[A]](rootNode) with Iterator[A] {
+  extends ChampBaseIterator[A, SetNode[A]](rootNode) {
 
   def next() = {
-    if (!hasNext)
-      throw new NoSuchElementException
+    if (!hasNext) Iterator.empty.next()
 
     val payload = currentValueNode.getPayload(currentValueCursor)
     currentValueCursor += 1
@@ -1899,11 +1898,10 @@ private final class SetIterator[A](rootNode: SetNode[A])
 }
 
 private final class SetReverseIterator[A](rootNode: SetNode[A])
-  extends ChampBaseReverseIterator[SetNode[A]](rootNode) with Iterator[A] {
+  extends ChampBaseReverseIterator[A, SetNode[A]](rootNode) {
 
   def next(): A = {
-    if (!hasNext)
-      throw new NoSuchElementException
+    if (!hasNext) Iterator.empty.next()
 
     val payload = currentValueNode.getPayload(currentValueCursor)
     currentValueCursor -= 1
@@ -1914,13 +1912,12 @@ private final class SetReverseIterator[A](rootNode: SetNode[A])
 }
 
 private final class SetHashIterator[A](rootNode: SetNode[A])
-  extends ChampBaseIterator[SetNode[A]](rootNode) with Iterator[AnyRef] {
+  extends ChampBaseIterator[AnyRef, SetNode[A]](rootNode) {
   private[this] var hash = 0
   override def hashCode(): Int = hash
 
   def next(): AnyRef = {
-    if (!hasNext)
-      throw new NoSuchElementException
+    if (!hasNext) Iterator.empty.next()
 
     hash = currentValueNode.getHash(currentValueCursor)
     currentValueCursor += 1
@@ -2089,7 +2086,7 @@ private[collection] final class HashSetBuilder[A] extends ReusableBuilder[A, Has
     ensureUnaliased()
     xs match {
       case hm: HashSet[A] =>
-        new ChampBaseIterator[SetNode[A]](hm.rootNode) {
+        new ChampBaseIterator[A, SetNode[A]](hm.rootNode) {
           while(hasNext) {
             val originalHash = currentValueNode.getHash(currentValueCursor)
             update(
@@ -2101,6 +2098,7 @@ private[collection] final class HashSetBuilder[A] extends ReusableBuilder[A, Has
             )
             currentValueCursor += 1
           }
+          override def next() = Iterator.empty.next()
         }
       case other =>
         val it = other.iterator

scala2-library-cc/src/scala/collection/immutable/Vector.scala

@@ -2230,7 +2230,7 @@ private object VectorStatics {
 }
 
 
-private final class NewVectorIterator[A](v: Vector[A], private[this] var totalLength: Int, private[this] val sliceCount: Int) extends Iterator[A] with java.lang.Cloneable {
+private final class NewVectorIterator[A](v: Vector[A], private[this] var totalLength: Int, private[this] val sliceCount: Int) extends AbstractIterator[A] with java.lang.Cloneable {
 
   private[this] var a1: Arr1 = v.prefix1
   private[this] var a2: Arr2 = _