Use JLine3

Minimal changes to support new API,
with basic completion and history.
JLine handles continuation line edit.

build.sbt

@@ -44,7 +44,9 @@ val junitDep          = "junit"                          % "junit"
 val junitInterfaceDep = "com.novocode"                   % "junit-interface"                  % "0.11"                            % "test"
 val jolDep            = "org.openjdk.jol"                % "jol-core"                         % "0.9"
 val asmDep            = "org.scala-lang.modules"         % "scala-asm"                        % versionProps("scala-asm.version")
-val jlineDep          = "jline"                          % "jline"                            % versionProps("jline.version")
+val jlineDep          = "org.jline"                      % "jline"                            % versionProps("jline.version")
+val jansiDep          = "org.fusesource.jansi"           % "jansi"                            % versionProps("jansi.version")
+val jnaDep            = "net.java.dev.jna"               % "jna"                              % versionProps("jna.version")
 val testInterfaceDep  = "org.scala-sbt"                  % "test-interface"                   % "1.0"
 val diffUtilsDep      = "com.googlecode.java-diff-utils" % "diffutils"                        % "1.3.0"
 
@@ -165,6 +167,7 @@ lazy val commonSettings = instanceSettings ++ clearSourceAndResourceDirectories
     "-doc-source-url", s"https://github.com/scala/scala/tree/${versionProperties.value.githubTree}€{FILE_PATH_EXT}#L€{FILE_LINE}"
   ),
   //maxErrors := 10,
+  maxErrors := 10,
   setIncOptions,
   apiURL := Some(url("https://www.scala-lang.org/api/" + versionProperties.value.mavenVersion + "/")),
   pomIncludeRepository := { _ => false },
@@ -406,7 +409,7 @@ lazy val compiler = configureAsSubproject(project)
     libraryDependencies += asmDep,
     // These are only needed for the POM:
     // TODO: jline dependency is only needed for the REPL shell, which should move to its own jar
-    libraryDependencies ++= Seq(jlineDep),
+    libraryDependencies ++= Seq(jlineDep, jansiDep, jnaDep),
     buildCharacterPropertiesFile := (resourceManaged in Compile).value / "scala-buildcharacter.properties",
     resourceGenerators in Compile += generateBuildCharacterPropertiesFile.map(file => Seq(file)).taskValue,
     // this a way to make sure that classes from interactive and scaladoc projects
@@ -444,9 +447,16 @@ lazy val compiler = configureAsSubproject(project)
       "-doc-root-content", (sourceDirectory in Compile).value + "/rootdoc.txt"
     ),
     Osgi.headers ++= Seq(
-      "Import-Package" -> ("jline.*;resolution:=optional," +
-                           raw"""scala.*;version="$${range;[==,=+);$${ver}}",""" +
-                           "*"),
+      "Import-Package" -> raw"""org.jline.keymap.*;resolution:=optional
+                            |org.jline.reader.*;resolution:=optional
+                            |org.jline.style.*;resolution:=optional
+                            |org.jline.terminal;resolution:=optional
+                            |org.jline.terminal.impl;resolution:=optional
+                            |org.jline.terminal.impl.jansi.*;resolution:=optional
+                            |org.jline.terminal.spi;resolution:=optional
+                            |org.jline.utils;resolution:=optional
+                            |scala.*;version="$${range;[==,=+);$${ver}}"
+                            |*""".stripMargin.linesIterator.mkString(","),
       "Class-Path" -> "scala-reflect.jar scala-library.jar"
     ),
     // Generate the ScriptEngineFactory service definition. The old Ant build did this when building
@@ -481,7 +491,7 @@ lazy val replFrontend = configureAsSubproject(Project("repl-frontend", file(".")
   .settings(disableDocs)
   .settings(skip in publish := true)
   .settings(
-    libraryDependencies += jlineDep,
+    libraryDependencies ++= Seq(jlineDep, jansiDep, jnaDep),
     name := "scala-repl-frontend"
   )
   .settings(
@@ -834,7 +844,7 @@ lazy val scalaDist = Project("scala-dist", file(".") / "target" / "scala-dist-di
       (htmlOut ** "*.html").get ++ (fixedManOut ** "*.1").get
     }.taskValue,
     managedResourceDirectories in Compile := Seq((resourceManaged in Compile).value),
-    libraryDependencies += jlineDep,
+    libraryDependencies ++= Seq(jlineDep, jansiDep, jnaDep),
     apiURL := None,
     fixPom(
       "/project/name" -> <name>Scala Distribution Artifacts</name>,
@@ -973,7 +983,7 @@ lazy val distDependencies = Seq(replFrontend, compiler, library, reflect, scalap
 lazy val dist = (project in file("dist"))
   .settings(commonSettings)
   .settings(
-    libraryDependencies ++= Seq(jlineDep),
+    libraryDependencies ++= Seq(jlineDep, jansiDep, jnaDep),
     mkBin := mkBinImpl.value,
     mkQuick := Def.task {
       val cp = (fullClasspath in IntegrationTest in LocalProject("test")).value
@@ -988,7 +998,13 @@ lazy val dist = (project in file("dist"))
     packageBin in Compile := {
       val targetDir = (buildDirectory in ThisBuild).value / "pack" / "lib"
       val jlineJAR = findJar((dependencyClasspath in Compile).value, jlineDep).get.data
-      val mappings = Seq((jlineJAR, targetDir / "jline.jar"))
+      val jansiJAR = findJar((dependencyClasspath in Compile).value, jansiDep).get.data
+      val jnaJAR   = findJar((dependencyClasspath in Compile).value, jnaDep).get.data
+      val mappings = Seq(
+        (jlineJAR, targetDir / "jline.jar"),
+        (jansiJAR, targetDir / "jansi.jar"),
+        (jnaJAR, targetDir / "jna.jar"),
+      )
       IO.copy(mappings, CopyOptions() withOverwrite true)
       targetDir
     },

src/compiler/scala/tools/nsc/fsc/ResidentScriptRunner.scala

@@ -13,7 +13,6 @@
 package scala.tools.nsc
 package fsc
 
-//import scala.tools.nsc.{AbstractScriptRunner, ScriptRunner, GenericRunnerSettings, Settings}
 import scala.reflect.io.Path
 import scala.util.control.NonFatal
 

src/compiler/scala/tools/nsc/settings/ScalaSettings.scala

@@ -121,7 +121,16 @@ trait ScalaSettings extends AbsScalaSettings
   val maxwarns           = IntSetting          ("-Xmaxwarns", "Maximum warnings to print", 100, None, _ => None)
   val Xmigration         = ScalaVersionSetting ("-Xmigration", "version", "Warn about constructs whose behavior may have changed since version.", initial = NoScalaVersion, default = Some(AnyScalaVersion))
   val nouescape          = BooleanSetting      ("-Xno-uescape", "Disable handling of \\u unicode escapes.")
-  val Xnojline           = BooleanSetting      ("-Xnojline", "Do not use JLine for editing.")
+  val Xjline             = ChoiceSetting       (
+    name    = "-Xjline",
+    helpArg = "mode",
+    descr   = "Select JLine mode.",
+    choices = List("emacs", "vi", "off"),
+    default = "emacs",
+    choicesHelp = List(
+      "emacs key bindings.",
+      "vi key bindings",
+      "No JLine editing."))
   val Xverify            = BooleanSetting      ("-Xverify", "Verify generic signatures in generated bytecode.")
   val plugin             = MultiStringSetting  ("-Xplugin", "paths", "Load a plugin from each classpath.")
   val disable            = MultiStringSetting  ("-Xplugin-disable", "plugin", "Disable plugins by name.")

src/partest/scala/tools/partest/ReplTest.scala

@@ -26,7 +26,7 @@ abstract class ReplTest extends DirectTest {
   // final because we need to enforce the existence of a couple settings.
   final override def settings: Settings = {
     val s = super.settings
-    s.Xnojline.value = true
+    s.Xjline.value = "off"
     if (getClass.getClassLoader.getParent != null) {
       s.classpath.value = s.classpath.value match {
         case "" => testOutput.toString