Merge pull request #2860 from Gedochao/feature/override-default-scala-launcher-option

Add launcher options allowing to override the default Scala version

Author: Gedochao

modules/build/src/main/scala/scala/build/preprocessing/ScriptPreprocessor.scala

@@ -158,25 +158,23 @@ case object ScriptPreprocessor extends Preprocessor {
     *   code wrapper compatible with provided BuildOptions
     */
   def getScriptWrapper(buildOptions: BuildOptions): CodeWrapper = {
-    val scalaVersionOpt = for {
-      maybeScalaVersion <- buildOptions.scalaOptions.scalaVersion
-      scalaVersion      <- maybeScalaVersion.versionOpt
-    } yield scalaVersion
+    val effectiveScalaVersion =
+      buildOptions.scalaOptions.scalaVersion.flatMap(_.versionOpt)
+        .orElse(buildOptions.scalaOptions.defaultScalaVersion)
+        .getOrElse(Constants.defaultScalaVersion)
 
     def objectCodeWrapperForScalaVersion =
       // AppObjectWrapper only introduces the 'main.sc' restriction when used in Scala 3, there's no gain in using it with Scala 3
-      if (scalaVersionOpt.exists(_.startsWith("2")))
-        AppCodeWrapper
-      else
-        ObjectCodeWrapper
+      if effectiveScalaVersion.startsWith("2") then AppCodeWrapper
+      else ObjectCodeWrapper
 
     buildOptions.scriptOptions.forceObjectWrapper match {
       case Some(true) => objectCodeWrapperForScalaVersion
       case _ =>
         buildOptions.scalaOptions.platform.map(_.value) match {
-          case Some(_: Platform.JS.type)                      => objectCodeWrapperForScalaVersion
-          case _ if scalaVersionOpt.exists(_.startsWith("2")) => AppCodeWrapper
-          case _                                              => ClassCodeWrapper
+          case Some(_: Platform.JS.type)                  => objectCodeWrapperForScalaVersion
+          case _ if effectiveScalaVersion.startsWith("2") => AppCodeWrapper
+          case _                                          => ClassCodeWrapper
         }
     }
   }

modules/cli/src/main/scala/scala/cli/ScalaCli.scala

@@ -16,6 +16,7 @@ import scala.cli.javaLauncher.JavaLauncherCli
 import scala.cli.launcher.{LauncherCli, LauncherOptions, PowerOptions}
 import scala.cli.publish.BouncycastleSignerMaker
 import scala.cli.util.ConfigDbUtils
+import scala.collection.mutable.ListBuffer
 import scala.util.Properties
 
 object ScalaCli {
@@ -53,6 +54,11 @@ object ScalaCli {
   private def isGraalvmNativeImage: Boolean =
     sys.props.contains("org.graalvm.nativeimage.imagecode")
 
+  private var defaultScalaVersion: Option[String]        = None
+  val launcherPredefinedRepositories: ListBuffer[String] = ListBuffer.empty
+
+  def getDefaultScalaVersion: String = defaultScalaVersion.getOrElse(Constants.defaultScalaVersion)
+
   private def partitionArgs(args: Array[String]): (Array[String], Array[String]) = {
     val systemProps = args.takeWhile(_.startsWith("-D"))
     (systemProps, args.drop(systemProps.size))
@@ -237,6 +243,10 @@ object ScalaCli {
                 && sys.props.get("scala-cli.kind").exists(_.startsWith("jvm")) =>
             JavaLauncherCli.runAndExit(args)
           case None =>
+            if launcherOpts.cliUserScalaVersion.nonEmpty then
+              defaultScalaVersion = launcherOpts.cliUserScalaVersion
+            if launcherOpts.cliPredefinedRepository.nonEmpty then
+              launcherPredefinedRepositories.addAll(launcherOpts.cliPredefinedRepository)
             if launcherOpts.powerOptions.power then
               isSipScala = false
               args0.toArray

modules/cli/src/main/scala/scala/cli/commands/ScalaCommand.scala

@@ -38,7 +38,8 @@ abstract class ScalaCommand[T <: HasGlobalOptions](implicit myParser: Parser[T],
   private val globalOptionsAtomic: AtomicReference[GlobalOptions] =
     new AtomicReference(GlobalOptions.default)
 
-  private def globalOptions: GlobalOptions = globalOptionsAtomic.get()
+  private def globalOptions: GlobalOptions  = globalOptionsAtomic.get()
+  protected def defaultScalaVersion: String = ScalaCli.getDefaultScalaVersion
 
   def sharedOptions(t: T): Option[SharedOptions] = // hello borked unused warning
     None
@@ -133,7 +134,7 @@ abstract class ScalaCommand[T <: HasGlobalOptions](implicit myParser: Parser[T],
                 .toOption
                 .flatten
                 .map(_.scalaVersion)
-                .getOrElse(Constants.defaultScalaVersion)
+                .getOrElse(defaultScalaVersion)
               val (fromIndex, completions) = cache.logger.use {
                 coursier.complete.Complete(cache)
                   .withInput(prefix)
@@ -313,13 +314,20 @@ abstract class ScalaCommand[T <: HasGlobalOptions](implicit myParser: Parser[T],
     *   change this behaviour.
     */
   def buildOptions(options: T): Option[BuildOptions] =
-    sharedOptions(options).map(shared => shared.buildOptions().orExit(shared.logger))
+    sharedOptions(options)
+      .map(shared => shared.buildOptions().orExit(shared.logger))
 
   protected def buildOptionsOrExit(options: T): BuildOptions =
-    buildOptions(options).getOrElse {
-      sharedOptions(options).foreach(_.logger.debug("build options could not be initialized"))
-      sys.exit(1)
-    }
+    buildOptions(options)
+      .map(bo =>
+        bo.copy(scalaOptions =
+          bo.scalaOptions.copy(defaultScalaVersion = Some(defaultScalaVersion))
+        )
+      )
+      .getOrElse {
+        sharedOptions(options).foreach(_.logger.debug("build options could not be initialized"))
+        sys.exit(1)
+      }
   override def shouldSuppressExperimentalFeatureWarnings: Boolean =
     globalOptions.globalSuppress.suppressExperimentalFeatureWarning
       .orElse {

modules/cli/src/main/scala/scala/cli/commands/package0/Package.scala

@@ -166,7 +166,10 @@ object Package extends ScalaCommand[PackageOptions] with BuildCommandHelpers {
   }
 
   def finalBuildOptions(options: PackageOptions): BuildOptions = {
-    val finalBuildOptions = options.finalBuildOptions.orExit(options.shared.logger)
+    val initialOptions = options.finalBuildOptions.orExit(options.shared.logger)
+    val finalBuildOptions = initialOptions.copy(scalaOptions =
+      initialOptions.scalaOptions.copy(defaultScalaVersion = Some(defaultScalaVersion))
+    )
     val buildOptions = finalBuildOptions.copy(
       javaOptions = finalBuildOptions.javaOptions.copy(
         javaOpts =

modules/cli/src/main/scala/scala/cli/commands/repl/Repl.scala

@@ -16,7 +16,6 @@ import scala.build.errors.{BuildException, CantDownloadAmmoniteError, FetchingDe
 import scala.build.input.Inputs
 import scala.build.internal.{Constants, Runner}
 import scala.build.options.{BuildOptions, JavaOpt, MaybeScalaVersion, Scope}
-import scala.cli.CurrentParams
 import scala.cli.commands.publish.ConfigUtil.*
 import scala.cli.commands.run.Run.{
   maybePrintSimpleScalacOutput,
@@ -30,6 +29,7 @@ import scala.cli.config.{ConfigDb, Keys}
 import scala.cli.packaging.Library
 import scala.cli.util.ArgHelpers.*
 import scala.cli.util.ConfigDbUtils
+import scala.cli.{CurrentParams, ScalaCli}
 import scala.jdk.CollectionConverters.*
 import scala.util.Properties
 
@@ -62,7 +62,7 @@ object Repl extends ScalaCommand[ReplOptions] {
       scalaOptions = baseOptions.scalaOptions.copy(
         scalaVersion = baseOptions.scalaOptions.scalaVersion
           .orElse {
-            val defaultScalaVer = scala.build.internal.Constants.defaultScalaVersion
+            val defaultScalaVer = ScalaCli.getDefaultScalaVersion
             val shouldDowngrade = {
               def needsDowngradeForAmmonite = {
                 import coursier.core.Version

modules/cli/src/main/scala/scala/cli/commands/shared/SharedOptions.scala

@@ -406,7 +406,10 @@ final case class SharedOptions(
         extraClassPath = extraRegularJarsAndClasspath,
         extraCompileOnlyJars = extraCompileOnlyClassPath,
         extraSourceJars = extraSourceJars.extractedClassPath ++ assumedSourceJars,
-        extraRepositories = dependencies.repository.map(_.trim).filter(_.nonEmpty),
+        extraRepositories =
+          (dependencies.repository ++ ScalaCli.launcherPredefinedRepositories).map(_.trim).filter(
+            _.nonEmpty
+          ),
         extraDependencies = ShadowingSeq.from(
           SharedOptions.parseDependencies(
             dependencies.dependency.map(Positioned.none),

modules/cli/src/main/scala/scala/cli/commands/version/Version.scala

@@ -5,12 +5,12 @@ import caseapp.core.help.HelpFormat
 
 import scala.build.Logger
 import scala.build.internal.Constants
-import scala.cli.CurrentParams
 import scala.cli.commands.shared.{HelpCommandGroup, HelpGroup}
 import scala.cli.commands.update.Update
 import scala.cli.commands.{CommandUtils, ScalaCommand, SpecificationLevel}
 import scala.cli.config.PasswordOption
 import scala.cli.util.ArgHelpers.*
+import scala.cli.{CurrentParams, ScalaCli}
 
 object Version extends ScalaCommand[VersionOptions] {
   override def group: String = HelpCommandGroup.Miscellaneous.toString
@@ -34,7 +34,7 @@ object Version extends ScalaCommand[VersionOptions] {
           else None
       }
     if options.cliVersion then println(Constants.version)
-    else if options.scalaVersion then println(Constants.defaultScalaVersion)
+    else if options.scalaVersion then println(ScalaCli.getDefaultScalaVersion)
     else {
       println(versionInfo)
       if !options.offline then
@@ -51,5 +51,5 @@ object Version extends ScalaCommand[VersionOptions] {
     val version            = Constants.version
     val detailedVersionOpt = Constants.detailedVersion.filter(_ != version).fold("")(" (" + _ + ")")
     s"""$fullRunnerName version: $version$detailedVersionOpt
-       |Scala version (default): ${Constants.defaultScalaVersion}""".stripMargin
+       |Scala version (default): ${ScalaCli.getDefaultScalaVersion}""".stripMargin
 }

modules/cli/src/main/scala/scala/cli/exportCmd/MillProjectDescriptor.scala

@@ -13,6 +13,7 @@ import scala.build.internal.Runner.frameworkName
 import scala.build.options.{BuildOptions, Platform, ScalaJsOptions, ScalaNativeOptions, Scope}
 import scala.build.testrunner.AsmTestRunner
 import scala.build.{Logger, Sources}
+import scala.cli.ScalaCli
 import scala.cli.util.SeqHelpers.*
 
 final case class MillProjectDescriptor(
@@ -39,7 +40,7 @@ final case class MillProjectDescriptor(
 
     val sv = options.scalaOptions.scalaVersion
       .flatMap(_.versionOpt) // FIXME If versionOpt is empty, the project is pure Java
-      .getOrElse(Constants.defaultScalaVersion)
+      .getOrElse(ScalaCli.getDefaultScalaVersion)
 
     if (pureJava)
       MillProject()

modules/cli/src/main/scala/scala/cli/exportCmd/SbtProjectDescriptor.scala

@@ -21,6 +21,7 @@ import scala.build.options.{
 }
 import scala.build.testrunner.AsmTestRunner
 import scala.build.{Logger, Positioned, Sources}
+import scala.cli.ScalaCli
 
 final case class SbtProjectDescriptor(
   sbtVersion: String,
@@ -122,7 +123,7 @@ final case class SbtProjectDescriptor(
     val scalaVerSetting = {
       val sv = options.scalaOptions.scalaVersion
         .flatMap(_.versionOpt) // FIXME If versionOpt is empty, the project is pure Java
-        .getOrElse(Constants.defaultScalaVersion)
+        .getOrElse(ScalaCli.getDefaultScalaVersion)
       s"""scalaVersion := "$sv""""
     }
 

modules/cli/src/main/scala/scala/cli/launcher/LauncherOptions.scala

@@ -3,7 +3,7 @@ package scala.cli.launcher
 import caseapp.*
 
 import scala.cli.commands.shared.HelpGroup
-import scala.cli.commands.tags
+import scala.cli.commands.{Constants, tags}
 
 @HelpMessage("Run another Scala CLI version")
 final case class LauncherOptions(
@@ -19,6 +19,24 @@ final case class LauncherOptions(
   @Hidden
   @Tag(tags.implementation)
   cliScalaVersion: Option[String] = None,
+  @Group(HelpGroup.Launcher.toString)
+  @HelpMessage(
+    s"The default version of Scala used when processing user inputs (current default: ${Constants.defaultScalaVersion}). Can be overridden with --scala-version. "
+  )
+  @ValueDescription("version")
+  @Hidden
+  @Tag(tags.implementation)
+  @Name("cliDefaultScalaVersion")
+  cliUserScalaVersion: Option[String] = None,
+  @Group(HelpGroup.Launcher.toString)
+  @HelpMessage("")
+  @Hidden
+  @Tag(tags.implementation)
+  @Name("r")
+  @Name("repo")
+  @Name("repository")
+  @Name("predefinedRepository")
+  cliPredefinedRepository: List[String] = Nil,
   @Recurse
   powerOptions: PowerOptions = PowerOptions()
 )