ass compile on 2.13

build.sbt

@@ -22,8 +22,9 @@ ThisBuild / version := Properties.envOrElse("VERSION", "0.0.0-dev") +
   (if ((ThisBuild / isSnapshot ).value) "-SNAPSHOT" else "")
 ThisBuild / isSnapshot := Properties.envOrElse("IS_SNAPSHOT","true").toBoolean
 ThisBuild / organization := "org.apache.toree.kernel"
-ThisBuild / crossScalaVersions := Seq("2.13.10")
-ThisBuild / scalaVersion := (ThisBuild / crossScalaVersions ).value.head
+ThisBuild / crossScalaVersions := Seq("2.13.8", "2.12.15")
+//ThisBuild / crossScalaVersions := Seq("2.12.15", "2.13.8")
+ThisBuild / scalaVersion := (ThisBuild / crossScalaVersions).value.head
 ThisBuild / Dependencies.sparkVersion := {
   val envVar = "APACHE_SPARK_VERSION"
   val defaultVersion = "3.3.2"
@@ -40,7 +41,7 @@ ThisBuild / Dependencies.sparkVersion := {
 
 // Compiler settings
 ThisBuild / scalacOptions ++= Seq(
-  "-deprecation",
+//  "-deprecation",
   "-unchecked",
   "-feature",
 //  "-Xfatal-warnings",

client/src/main/scala/org/apache/toree/kernel/protocol/v5/client/Utilities.scala

@@ -26,6 +26,7 @@ import org.apache.toree.kernel.protocol.v5.content.ExecuteRequest
 import org.apache.toree.utils.LogLike
 import play.api.libs.json.{JsPath, Json, JsonValidationError, Reads}
 
+import scala.collection.mutable
 import scala.concurrent.duration._
 
 object Utilities extends LogLike {
@@ -78,15 +79,15 @@ object Utilities extends LogLike {
   }
 
   implicit def KernelMessageToZMQMessage(kernelMessage : KernelMessage) : ZMQMessage = {
-    var frames: Seq[ByteString] = Seq()
-    kernelMessage.ids.map((id : Array[Byte]) => frames = frames :+ ByteString.apply(id) )
-    frames = frames :+ "<IDS|MSG>"
-    frames = frames :+ kernelMessage.signature
-    frames = frames :+ Json.toJson(kernelMessage.header).toString()
-    frames = frames :+ Json.toJson(kernelMessage.parentHeader).toString()
-    frames = frames :+ Json.toJson(kernelMessage.metadata).toString
-    frames = frames :+ kernelMessage.contentString
-    ZMQMessage(frames  : _*)
+    val frames: mutable.ListBuffer[ByteString] = scala.collection.mutable.ListBuffer()
+    kernelMessage.ids.map((id: Array[Byte]) => frames += ByteString.apply(id))
+    frames += "<IDS|MSG>"
+    frames += kernelMessage.signature
+    frames += Json.toJson(kernelMessage.header).toString()
+    frames += Json.toJson(kernelMessage.parentHeader).toString()
+    frames += Json.toJson(kernelMessage.metadata).toString
+    frames += kernelMessage.contentString
+    ZMQMessage(frames.toSeq : _*)
   }
 
   def parseAndHandle[T](json: String, reads: Reads[T], handler: T => Unit) : Unit = {

kernel-api/src/main/scala/org/apache/toree/dependencies/CoursierDependencyDownloader.scala

@@ -298,11 +298,11 @@ object Credentials {
       p
     }
 
-    private def findKey(keys: collection.Seq[String]) = keys
+    private def findKey(keys: collection.Seq[String]): String = keys
       .iterator
       .map(props.getProperty)
       .filter(_ != null)
-      .to(LazyList)
+      .toStream
       .headOption
       .getOrElse {
         throw new NoSuchElementException(s"${keys.head} key in $file")

kernel-api/src/main/scala/org/apache/toree/magic/InternalClassLoader.scala

@@ -29,7 +29,7 @@ class InternalClassLoader(
 
   // TODO: Provides an exposed reference to the super loadClass to be stubbed
   // out in tests.
-  private[magic] def parentLoadClass(name: String, resolve: Boolean) =
+  private[magic] def parentLoadClass(name: String, resolve: Boolean): Class[_] =
     super.loadClass(name, resolve)
 
   /**

kernel-api/src/main/scala/org/apache/toree/utils/MultiClassLoader.scala

@@ -42,7 +42,7 @@ class MultiClassLoader(
   private val classLoaders: collection.Seq[ClassLoader]
 ) extends URLClassLoader(
   classLoaders.flatMap({
-    case urlClassLoader: URLClassLoader => urlClassLoader.getURLs.to(collection.Seq)
+    case urlClassLoader: URLClassLoader => urlClassLoader.getURLs.toSeq
     case _                              => Nil
   }).distinct.toArray,
   /* Create a parent chain based on a each classloader's parent */ {

kernel/src/main/scala/org/apache/toree/kernel/protocol/v5/handler/CommInfoRequestHandler.scala

@@ -40,10 +40,10 @@ class CommInfoRequestHandler(
   extends BaseHandler(actorLoader) with MessageLogSupport
 {
 
-  def buildCommMap(targetName: String) = {
+  def buildCommMap(targetName: String): Map[UUID, Map[UUID, UUID]] = {
     commStorage.getCommIdsFromTarget(targetName) match {
       case Some(commVector) => {
-        commVector.map(x => Map(x -> Map("target_name" -> targetName))).flatten.toMap
+        commVector.flatMap(x => Map(x -> Map("target_name" -> targetName))).toMap
       }
       case _ => {
         Map()
@@ -54,13 +54,14 @@ class CommInfoRequestHandler(
   override def process(kernelMessage: KernelMessage): Future[_] = Future {
     logKernelMessageAction("Initiating CommInfo request for", kernelMessage)
     import scala.language.existentials
-    val commMap = (Json.parse(kernelMessage.contentString) \ "target_name").asOpt[String] match {
+    val commMap: Map[String, Map[String, String]] =
+      (Json.parse(kernelMessage.contentString) \ "target_name").asOpt[String] match {
       case Some(targetName) => {
         buildCommMap(targetName)
       }
       case None => {
-        //target_name is missing from the kernel message so return all comms over every target
-        commStorage.getTargets().map(buildCommMap(_))
+        // target_name is missing from the kernel message so return all comms over every target
+        commStorage.getTargets().map(buildCommMap).reduce(_ ++ _)
       }
     }
     val commInfoReply = CommInfoReply(commMap.asInstanceOf[Map[String, Map[String, String]]])

kernel/src/main/scala/org/apache/toree/kernel/protocol/v5/kernel/Utilities.scala

@@ -26,6 +26,7 @@ import org.apache.toree.utils.LogLike
 import play.api.libs.json.JsonValidationError
 import play.api.libs.json.{JsPath, Json, Reads}
 
+import scala.collection.mutable
 import scala.concurrent.duration._
 
 object Utilities extends LogLike {
@@ -77,15 +78,15 @@ object Utilities extends LogLike {
   }
 
   implicit def KernelMessageToZMQMessage(kernelMessage : KernelMessage) : ZMQMessage = {
-    var frames: Seq[ByteString] = Seq()
-    kernelMessage.ids.map((id : Array[Byte]) => frames = frames :+ ByteString.apply(id) )
-    frames = frames :+ "<IDS|MSG>"
-    frames = frames :+ kernelMessage.signature
-    frames = frames :+ Json.toJson(kernelMessage.header).toString()
-    frames = frames :+ Json.toJson(kernelMessage.parentHeader).toString()
-    frames = frames :+ Json.toJson(kernelMessage.metadata).toString
-    frames = frames :+ kernelMessage.contentString
-    ZMQMessage(frames  : _*)
+    val frames: mutable.ListBuffer[ByteString] = mutable.ListBuffer()
+    kernelMessage.ids.map((id: Array[Byte]) => frames += ByteString.apply(id))
+    frames += "<IDS|MSG>"
+    frames += kernelMessage.signature
+    frames += Json.toJson(kernelMessage.header).toString()
+    frames += Json.toJson(kernelMessage.parentHeader).toString()
+    frames += Json.toJson(kernelMessage.metadata).toString
+    frames += kernelMessage.contentString
+    ZMQMessage(frames.toSeq : _*)
   }
 
   def parseAndHandle[T, U](json: String, reads: Reads[T],

kernel/src/main/scala/org/apache/toree/magic/builtin/AddDeps.scala

@@ -91,7 +91,7 @@ class AddDeps extends LineMagic with IncludeInterpreter
       } else {
         (x, "*")
       }
-    }: (String, String)).to(collection.Set)
+    }: (String, String)).toSet
 
     val repositoriesWithCreds = dependencyDownloader.resolveRepositoriesAndCredentials(repository, credentials)
 

kernel/src/test/scala/org/apache/toree/kernel/protocol/v5/kernel/socket/SocketConfigSpec.scala

@@ -71,7 +71,7 @@ class SocketConfigSpec extends AnyFunSpec with Matchers {
         val CompleteRequestResults = socketConfigJson.validate[SocketConfig]
 
         CompleteRequestResults.fold(
-          (invalid: Seq[(JsPath, Seq[JsonValidationError])]) => println("Failed!"),
+          (invalid: collection.Seq[(JsPath, collection.Seq[JsonValidationError])]) => println("Failed!"),
           (valid: SocketConfig) => valid
         ) should be (socketConfig)
       }

kernel/src/test/scala/org/apache/toree/kernel/protocol/v5/stream/KernelOuputStreamSpec.scala

@@ -239,7 +239,7 @@ class KernelOuputStreamSpec
         val message = kernelOutputRelayProbe
           .receiveOne(MaxAkkaTestTimeout).asInstanceOf[KernelMessage]
 
-        message.ids(0).deep should equal (MessageType.Outgoing.Stream.toString.getBytes.deep)
+        message.ids.head.toIndexedSeq should equal (MessageType.Outgoing.Stream.toString.getBytes.toIndexedSeq)
       }
 
       it("should set the message type in the header of the kernel message to an execute_result") {

kernel/src/test/scala/test/utils/DummyInterpreter.scala

@@ -17,13 +17,12 @@
 
 package test.utils
 
-import java.net.URL
-
 import org.apache.toree.interpreter.Results.Result
 import org.apache.toree.interpreter.{ExecuteFailure, ExecuteOutput, Interpreter, LanguageInfo}
 import org.apache.toree.kernel.api.KernelLike
 
-import scala.tools.nsc.interpreter.{InputStream, OutputStream}
+import java.io.{InputStream, OutputStream}
+import java.net.URL
 
 class DummyInterpreter(kernel: KernelLike) extends Interpreter {
   /**

macros/project/plugins.sbt

@@ -16,4 +16,6 @@
  */
 resolvers += Resolver.sonatypeRepo("releases")
 
-addCompilerPlugin("org.scalamacros" % "paradise" % "2.1.1" cross CrossVersion.full)
+if (scalaBinaryVersion.value == "2.12") {
+  addCompilerPlugin("org.scalamacros" % "paradise" % "2.1.1" cross CrossVersion.full)
+}

plugins/src/main/scala/org/apache/toree/plugins/PluginSearcher.scala

@@ -75,8 +75,8 @@ class PluginSearcher {
       s"Failed to load class info from classpath: ${classFinder.classpath.mkString(",")}",
       _: Throwable
     ))
-    val stream = tryStream.getOrElse(LazyList.empty)
-    ClassFinder.classInfoMap(stream.iterator)
+    val stream = tryStream.getOrElse(Stream.empty)
+    ClassFinder.classInfoMap(stream.toIterator)
   }
 
   /**

plugins/src/test/scala-2.13/org/apache/toree/plugins/dependencies/ClassLoaderHelper.scala

@@ -0,0 +1,29 @@
+/*
+ *  Licensed to the Apache Software Foundation (ASF) under one or more
+ *  contributor license agreements.  See the NOTICE file distributed with
+ *  this work for additional information regarding copyright ownership.
+ *  The ASF licenses this file to You under the Apache License, Version 2.0
+ *  (the "License"); you may not use this file except in compliance with
+ *  the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License
+ */
+package org.apache.toree.plugins.dependencies
+
+import java.net.URL
+import java.lang.{ClassLoader => JClassLoader}
+
+import scala.reflect.internal.util.ScalaClassLoader
+
+object ClassLoaderHelper {
+
+  def URLClassLoader(urls: Seq[URL], parent: JClassLoader): ScalaClassLoader.URLClassLoader = {
+    new scala.reflect.internal.util.ScalaClassLoader.URLClassLoader(urls, parent)
+  }
+}

project/Dependencies.scala

@@ -21,10 +21,10 @@ import scala.util.Properties
 object Dependencies {
 
   // Libraries
-
-  val akkaActor = "com.typesafe.akka" %% "akka-actor" % "2.7.0" // Apache v2
-  val akkaSlf4j = "com.typesafe.akka" %% "akka-slf4j" % "2.7.0" // Apache v2
-  val akkaTestkit = "com.typesafe.akka" %% "akka-testkit" % "2.7.0" // Apache v2
+  val akkaVersion = "2.6.21" // The latest version under Apache v2
+  val akkaActor = "com.typesafe.akka" %% "akka-actor" % akkaVersion // Apache v2
+  val akkaSlf4j = "com.typesafe.akka" %% "akka-slf4j" % akkaVersion // Apache v2
+  val akkaTestkit = "com.typesafe.akka" %% "akka-testkit" % akkaVersion // Apache v2
 
   val clapper = "org.clapper" %% "classutil" % "1.5.1" // BSD 3-clause license, used for detecting plugins
 

protocol/src/main/scala/org/apache/toree/kernel/protocol/v5/package.scala

@@ -36,7 +36,7 @@ package object v5 {
         Map.empty
       } else {
         // triple quotes due https://github.com/scala/bug/issues/6476
-        kv.toMap.view.mapValues(v => Json.parse(s""""$v"""")).toMap
+        kv.toMap.mapValues(v => Json.parse(s""""$v"""")).toMap
       }
     }
 

protocol/src/test/scala/org/apache/toree/kernel/protocol/v5/HeaderSpec.scala

@@ -63,7 +63,7 @@ class HeaderSpec extends AnyFunSpec with Matchers {
         val headerResults = headerJson.validate[Header]
 
         headerResults.fold(
-          (invalid: Seq[(JsPath, Seq[JsonValidationError])]) => println("Failed!"),
+          (invalid: collection.Seq[(JsPath, collection.Seq[JsonValidationError])]) => println("Failed!"),
           (valid: Header) => valid
         ) should be (header)
       }

protocol/src/test/scala/org/apache/toree/kernel/protocol/v5/content/ClearOutputSpec.scala

@@ -59,7 +59,7 @@ class ClearOutputSpec extends AnyFunSpec with Matchers {
         val CompleteRequestResults = clearOutputJson.validate[ClearOutput]
 
         CompleteRequestResults.fold(
-          (invalid: Seq[(JsPath, Seq[JsonValidationError])]) => println("Failed!"),
+          (invalid: collection.Seq[(JsPath, collection.Seq[JsonValidationError])]) => println("Failed!"),
           (valid: ClearOutput) => valid
         ) should be (clearOutput)
       }

protocol/src/test/scala/org/apache/toree/kernel/protocol/v5/content/CommCloseSpec.scala

@@ -60,7 +60,7 @@ class CommCloseSpec extends AnyFunSpec with Matchers {
         val CompleteRequestResults = commCloseJson.validate[CommClose]
 
         CompleteRequestResults.fold(
-          (invalid: Seq[(JsPath, Seq[JsonValidationError])]) => println("Failed!"),
+          (invalid: collection.Seq[(JsPath, collection.Seq[JsonValidationError])]) => println("Failed!"),
           (valid: CommClose) => valid
         ) should be (commClose)
       }

protocol/src/test/scala/org/apache/toree/kernel/protocol/v5/content/CommMsgSpec.scala

@@ -88,7 +88,7 @@ class CommMsgSpec extends AnyFunSpec with Matchers {
         val CompleteRequestResults = commMsgJson.validate[CommMsg]
 
         CompleteRequestResults.fold(
-          (invalid: Seq[(JsPath, Seq[JsonValidationError])]) => println("Failed!"),
+          (invalid: collection.Seq[(JsPath, collection.Seq[JsonValidationError])]) => println("Failed!"),
           (valid: CommMsg) => valid
         ) should be (commMsg)
       }

protocol/src/test/scala/org/apache/toree/kernel/protocol/v5/content/CommOpenSpec.scala

@@ -61,7 +61,7 @@ class CommOpenSpec extends AnyFunSpec with Matchers {
         val CompleteRequestResults = commOpenJson.validate[CommOpen]
 
         CompleteRequestResults.fold(
-          (invalid: Seq[(JsPath, Seq[JsonValidationError])]) => println("Failed!"),
+          (invalid: collection.Seq[(JsPath, collection.Seq[JsonValidationError])]) => println("Failed!"),
           (valid: CommOpen) => valid
         ) should be (commOpen)
       }

protocol/src/test/scala/org/apache/toree/kernel/protocol/v5/content/CompleteReplyErrorSpec.scala

@@ -61,7 +61,7 @@ class CompleteReplyErrorSpec extends AnyFunSpec with Matchers {
         val CompleteReplyOkResults = completeReplyErrorJson.validate[CompleteReplyError]
 
         CompleteReplyOkResults.fold(
-          (invalid: Seq[(JsPath, Seq[JsonValidationError])]) => println("Failed!"),
+          (invalid: collection.Seq[(JsPath, collection.Seq[JsonValidationError])]) => println("Failed!"),
           (valid: CompleteReplyError) => valid
         ) should be (completeReplyError)
       }

protocol/src/test/scala/org/apache/toree/kernel/protocol/v5/content/CompleteReplyOkSpec.scala

@@ -57,7 +57,7 @@ class CompleteReplyOkSpec extends AnyFunSpec with Matchers {
         val CompleteReplyOkResults = completeReplyOkJson.validate[CompleteReplyOk]
 
         CompleteReplyOkResults.fold(
-          (invalid: Seq[(JsPath, Seq[JsonValidationError])]) => println("Failed!"),
+          (invalid: collection.Seq[(JsPath, collection.Seq[JsonValidationError])]) => println("Failed!"),
           (valid: CompleteReplyOk) => valid
         ) should be (completeReplyOk)
       }

protocol/src/test/scala/org/apache/toree/kernel/protocol/v5/content/CompleteReplySpec.scala

@@ -64,7 +64,7 @@ class CompleteReplySpec extends AnyFunSpec with Matchers {
         val CompleteReplyResults = completeReplyJson.validate[CompleteReply]
 
         CompleteReplyResults.fold(
-          (invalid: Seq[(JsPath, Seq[JsonValidationError])]) => println("Failed!"),
+          (invalid: collection.Seq[(JsPath, collection.Seq[JsonValidationError])]) => println("Failed!"),
           (valid: CompleteReply) => valid
         ) should be (completeReply)
       }

protocol/src/test/scala/org/apache/toree/kernel/protocol/v5/content/CompleteRequestSpec.scala

@@ -60,7 +60,7 @@ class CompleteRequestSpec extends AnyFunSpec with Matchers {
         val CompleteRequestResults = completeRequestJson.validate[CompleteRequest]
 
         CompleteRequestResults.fold(
-          (invalid: Seq[(JsPath, Seq[JsonValidationError])]) => println("Failed!"),
+          (invalid: collection.Seq[(JsPath, collection.Seq[JsonValidationError])]) => println("Failed!"),
           (valid: CompleteRequest) => valid
         ) should be (completeRequest)
       }

protocol/src/test/scala/org/apache/toree/kernel/protocol/v5/content/ConnectReplySpec.scala

@@ -62,7 +62,7 @@ class ConnectReplySpec extends AnyFunSpec with Matchers {
         val ConnectReplyResults = connectReplyJson.validate[ConnectReply]
 
         ConnectReplyResults.fold(
-          (invalid: Seq[(JsPath, Seq[JsonValidationError])]) => println("Failed!"),
+          (invalid: collection.Seq[(JsPath, collection.Seq[JsonValidationError])]) => println("Failed!"),
           (valid: ConnectReply) => valid
         ) should be (connectReply)
       }

protocol/src/test/scala/org/apache/toree/kernel/protocol/v5/content/ConnectRequestSpec.scala

@@ -55,7 +55,7 @@ class ConnectRequestSpec extends AnyFunSpec with Matchers {
         val ConnectRequestResults = connectRequestJson.validate[ConnectRequest]
 
         ConnectRequestResults.fold(
-          (invalid: Seq[(JsPath, Seq[JsonValidationError])]) => println("Failed!"),
+          (invalid: collection.Seq[(JsPath, collection.Seq[JsonValidationError])]) => println("Failed!"),
           (valid: ConnectRequest) => valid
         ) should be (connectRequest)
       }

protocol/src/test/scala/org/apache/toree/kernel/protocol/v5/content/DisplayDataSpec.scala

@@ -62,7 +62,7 @@ class DisplayDataSpec extends AnyFunSpec with Matchers {
         val displayDataResults = displayDataJson.validate[DisplayData]
 
         displayDataResults.fold(
-          (invalid: Seq[(JsPath, Seq[JsonValidationError])]) => println("Failed!"),
+          (invalid: collection.Seq[(JsPath, collection.Seq[JsonValidationError])]) => println("Failed!"),
           (valid: DisplayData) => valid
         ) should be (displayData)
       }

protocol/src/test/scala/org/apache/toree/kernel/protocol/v5/content/ErrorContentSpec.scala

@@ -58,7 +58,7 @@ class ErrorContentSpec extends AnyFunSpec with Matchers {
         val CompleteRequestResults = errorJson.validate[ErrorContent]
 
         CompleteRequestResults.fold(
-          (invalid: Seq[(JsPath, Seq[JsonValidationError])]) => println("Failed!"),
+          (invalid: collection.Seq[(JsPath, collection.Seq[JsonValidationError])]) => println("Failed!"),
           (valid: ErrorContent) => valid
         ) should be (error)
       }

protocol/src/test/scala/org/apache/toree/kernel/protocol/v5/content/ExecuteInputSpec.scala

@@ -60,7 +60,7 @@ class ExecuteInputSpec extends AnyFunSpec with Matchers {
         val executeInputResults = executeInputJson.validate[ExecuteInput]
 
         executeInputResults.fold(
-          (invalid: Seq[(JsPath, Seq[JsonValidationError])]) => println("Failed!"),
+          (invalid: collection.Seq[(JsPath, collection.Seq[JsonValidationError])]) => println("Failed!"),
           (valid: ExecuteInput) => valid
         ) should be (executeInput)
       }