uptake IterationType (#640)

* start work uptaking IterationType

* try to fix tests

* Update IteratorSerializerModule.scala

Author: pjfanning

src/main/scala/com/fasterxml/jackson/module/scala/modifiers/ScalaTypeModifier.scala

@@ -18,6 +18,7 @@ class ScalaTypeModifier extends TypeModifier {
   private val longClass = classOf[Long]
   private val immutableLongMapClass = classOf[immutable.LongMap[_]]
   private val mutableLongMapClass = classOf[mutable.LongMap[_]]
+  private val iteratorClass = classOf[Iterator[_]]
   private val iterableOnceClass = classOf[IterableOnce[_]]
 
   override def modifyType(javaType: JavaType,
@@ -39,6 +40,8 @@ class ScalaTypeModifier extends TypeModifier {
       } else {
         MapLikeType.upgradeFrom(javaType, javaType.containedTypeOrUnknown(0), javaType.containedTypeOrUnknown(1))
       }
+    } else if (javaType.isTypeOrSubTypeOf(iteratorClass)) {
+      IterationType.upgradeFrom(javaType, javaType.containedTypeOrUnknown(0))
     } else if (javaType.isTypeOrSubTypeOf(iterableOnceClass)) {
       CollectionLikeType.upgradeFrom(javaType, javaType.containedTypeOrUnknown(0))
     } else if (javaType.isTypeOrSubTypeOf(eitherClass)) {

src/main/scala/com/fasterxml/jackson/module/scala/ser/IteratorSerializerModule.scala

@@ -3,10 +3,9 @@ package module.scala
 package ser
 
 import java.{lang => jl}
-
 import com.fasterxml.jackson.core.JsonGenerator
 import com.fasterxml.jackson.databind._
-import com.fasterxml.jackson.databind.`type`.CollectionLikeType
+import com.fasterxml.jackson.databind.`type`.{CollectionLikeType, IterationType}
 import com.fasterxml.jackson.databind.jsontype.TypeSerializer
 import com.fasterxml.jackson.databind.ser.std.AsArraySerializerBase
 import com.fasterxml.jackson.databind.ser.Serializers
@@ -75,6 +74,21 @@ private object ScalaIteratorSerializerResolver extends Serializers.Base {
     if (!SCALAITERATOR_CLASS.isAssignableFrom(rawClass) || JSONSERIALIZABLE_CLASS.isAssignableFrom(rawClass)) None.orNull
     else new UnresolvedIteratorSerializer(rawClass, collectionType.getContentType, false, elementTypeSerializer, elementSerializer)
   }
+
+  override def findSerializer(config: SerializationConfig, `type`: JavaType, beanDesc: BeanDescription): JsonSerializer[_] = {
+    `type` match {
+      case it: IterationType => {
+        val rawClass = it.getRawClass
+        if (JSONSERIALIZABLE_CLASS.isAssignableFrom(rawClass)) {
+          None.orNull
+        } else {
+          new UnresolvedIteratorSerializer(it.getRawClass, config.constructType(classOf[AnyRef]), false,
+            None.orNull, None.orNull)
+        }
+      }
+      case _ => None.orNull
+    }
+  }
 }
 
 trait IteratorSerializerModule extends IteratorTypeModifierModule {