Add platform option

modules/cli-options/src/main/scala/scala/cli/commands/SharedOptions.scala

@@ -84,6 +84,10 @@ final case class SharedOptions(
   @Name("resourceDir")
     resourceDirs: List[String] = Nil,
 
+  @HelpMessage("Specify platform")
+  @ValueDescription("scala-js|scala-native|jvm")
+    platform: Option[String] = None,
+
   @Group("Scala")
   @Hidden
     scalaLibrary: Option[Boolean] = None,

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

@@ -61,7 +61,7 @@ object Bsp extends ScalaCommand[BspOptions] {
       val sharedOptions = getSharedOptions()
       BspReloadableOptions(
         buildOptions = buildOptions(sharedOptions),
-        bloopRifleConfig = sharedOptions.bloopRifleConfig(),
+        bloopRifleConfig = sharedOptions.bloopRifleConfig().orExit(sharedOptions.logger),
         logger = sharedOptions.logging.logger,
         verbosity = sharedOptions.logging.verbosity
       )
@@ -96,7 +96,8 @@ object Bsp extends ScalaCommand[BspOptions] {
   }
 
   private def buildOptions(sharedOptions: SharedOptions): BuildOptions = {
-    val baseOptions = sharedOptions.buildOptions()
+    val logger      = sharedOptions.logger
+    val baseOptions = sharedOptions.buildOptions().orExit(logger)
     baseOptions.copy(
       classPathOptions = baseOptions.classPathOptions.copy(
         fetchSources = baseOptions.classPathOptions.fetchSources.orElse(Some(true))

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

@@ -20,8 +20,8 @@ object Compile extends ScalaCommand[CompileOptions] {
 
   def run(options: CompileOptions, args: RemainingArgs): Unit = {
     maybePrintGroupHelp(options)
-    maybePrintSimpleScalacOutput(options, options.shared.buildOptions())
     val logger = options.shared.logger
+    maybePrintSimpleScalacOutput(options, options.shared.buildOptions().orExit(logger))
     CurrentParams.verbosity = options.shared.logging.verbosity
     val inputs = options.shared.inputs(args.all).orExit(logger)
     CurrentParams.workspaceOpt = Some(inputs.workspace)
@@ -76,10 +76,10 @@ object Compile extends ScalaCommand[CompileOptions] {
       }
     }
 
-    val buildOptions = options.shared.buildOptions()
+    val buildOptions = options.shared.buildOptions().orExit(logger)
     val threads      = BuildThreads.create()
 
-    val compilerMaker = options.shared.compilerMaker(threads)
+    val compilerMaker = options.shared.compilerMaker(threads).orExit(logger)
     val configDb = ConfigDb.open(options.shared.directories.directories)
       .orExit(logger)
     val actionableDiagnostics =

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

@@ -21,7 +21,7 @@ object DependencyUpdate extends ScalaCommand[DependencyUpdateOptions] {
 
     val logger       = options.shared.logger
     val inputs       = options.shared.inputs(args.all).orExit(logger)
-    val buildOptions = options.shared.buildOptions()
+    val buildOptions = options.shared.buildOptions().orExit(logger)
 
     val (crossSources, _) =
       CrossSources.forInputs(

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

@@ -27,10 +27,11 @@ object Doc extends ScalaCommand[DocOptions] {
     val inputs = options.shared.inputs(args.remaining).orExit(logger)
     CurrentParams.workspaceOpt = Some(inputs.workspace)
 
-    val initialBuildOptions = options.shared.buildOptions(enableJmh = false, jmhVersion = None)
-    val threads             = BuildThreads.create()
+    val initialBuildOptions =
+      options.shared.buildOptions(enableJmh = false, jmhVersion = None).orExit(logger)
+    val threads = BuildThreads.create()
 
-    val maker               = options.shared.compilerMaker(threads)
+    val maker               = options.shared.compilerMaker(threads).orExit(logger)
     val compilerMaker       = ScalaCompilerMaker.IgnoreScala2(maker)
     val docCompilerMakerOpt = Some(SimpleScalaCompilerMaker("java", Nil, scaladoc = true))
 

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

@@ -102,7 +102,7 @@ object Export extends ScalaCommand[ExportOptions] {
     val inputs = options.shared.inputs(args.all).orExit(logger)
     CurrentParams.workspaceOpt = Some(inputs.workspace)
     val baseOptions =
-      options.shared.buildOptions()
+      options.shared.buildOptions().orExit(logger)
         .copy(mainClass = options.mainClass.mainClass.filter(_.nonEmpty))
 
     val (sourcesMain, optionsMain0) =

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

@@ -39,8 +39,8 @@ object Fmt extends ScalaCommand[FmtOptions] {
       }
     CurrentParams.workspaceOpt = Some(workspace)
     val (versionMaybe, dialectMaybe, pathMaybe) = readVersionAndDialect(workspace, options, logger)
-    val cache                                   = options.shared.buildOptions().archiveCache
-    val buildOptions                            = options.buildOptions
+    val cache        = options.shared.buildOptions().orExit(logger).archiveCache
+    val buildOptions = options.buildOptions
 
     if (sourceFiles.isEmpty)
       logger.debug("No source files, not formatting anything")

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

@@ -46,7 +46,7 @@ object Metabrowse extends ScalaCommand[MetabrowseOptions] {
     val inputs = options.shared.inputs(args.all).orExit(logger)
     CurrentParams.workspaceOpt = Some(inputs.workspace)
 
-    val baseOptions = options.shared.buildOptions()
+    val baseOptions = options.shared.buildOptions().orExit(logger)
     val initialBuildOptions = baseOptions.copy(
       classPathOptions = baseOptions.classPathOptions.copy(
         fetchSources = Some(true)
@@ -57,7 +57,7 @@ object Metabrowse extends ScalaCommand[MetabrowseOptions] {
     )
     val threads = BuildThreads.create()
 
-    val compilerMaker = options.shared.compilerMaker(threads)
+    val compilerMaker = options.shared.compilerMaker(threads).orExit(logger)
     val configDb = ConfigDb.open(options.shared.directories.directories)
       .orExit(logger)
     val actionableDiagnostics =

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

@@ -58,7 +58,7 @@ object Package extends ScalaCommand[PackageOptions] with BuildCommandHelpers {
 
     val initialBuildOptions = buildOptions(options)
     val threads             = BuildThreads.create()
-    val compilerMaker       = options.compilerMaker(threads)
+    val compilerMaker       = options.compilerMaker(threads).orExit(logger)
     val docCompilerMakerOpt = options.docCompilerMakerOpt
 
     val cross = options.compileCross.cross.getOrElse(false)

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

@@ -29,6 +29,7 @@ object Repl extends ScalaCommand[ReplOptions] {
     import ops.sharedRepl._
     val ammoniteVersionOpt = ammoniteVersion.map(_.trim).filter(_.nonEmpty)
 
+    val logger = ops.shared.logger
     val baseOptions = shared.copy(scalaVersion =
       if (
         ammonite.contains(true) &&
@@ -41,7 +42,7 @@ object Repl extends ScalaCommand[ReplOptions] {
         Some("3.1.3")
       }
       else shared.scalaVersion
-    ).buildOptions()
+    ).buildOptions().orExit(logger)
     baseOptions.copy(
       javaOptions = baseOptions.javaOptions.copy(
         javaOpts =
@@ -77,7 +78,7 @@ object Repl extends ScalaCommand[ReplOptions] {
 
     val threads = BuildThreads.create()
 
-    val compilerMaker = options.shared.compilerMaker(threads)
+    val compilerMaker = options.shared.compilerMaker(threads).orExit(logger)
 
     val directories = options.shared.directories.directories
 

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

@@ -57,10 +57,11 @@ object Run extends ScalaCommand[RunOptions] with BuildCommandHelpers {
   def buildOptions(options: RunOptions): BuildOptions = {
     import options.*
     import options.sharedRun.*
+    val logger = options.shared.logger
     val baseOptions = shared.buildOptions(
       enableJmh = benchmarking.jmh.contains(true),
       jmhVersion = benchmarking.jmhVersion
-    )
+    ).orExit(logger)
     baseOptions.copy(
       mainClass = mainClass.mainClass,
       javaOptions = baseOptions.javaOptions.copy(
@@ -115,7 +116,7 @@ object Run extends ScalaCommand[RunOptions] with BuildCommandHelpers {
     CurrentParams.workspaceOpt = Some(inputs.workspace)
     val threads = BuildThreads.create()
 
-    val compilerMaker = options.shared.compilerMaker(threads)
+    val compilerMaker = options.shared.compilerMaker(threads).orExit(logger)
 
     def maybeRun(
       build: Build.Successful,

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

@@ -87,8 +87,9 @@ abstract class ScalaCommand[T](implicit myParser: Parser[T], help: Help[T])
         val candidates = arg.name.name match {
           case "dependency" =>
             state.flatMap(sharedOptions).toList.flatMap { sharedOptions =>
-              val cache = sharedOptions.coursierCache
-              val sv = sharedOptions.buildOptions()
+              val logger = sharedOptions.logger
+              val cache  = sharedOptions.coursierCache
+              val sv = sharedOptions.buildOptions().orExit(logger)
                 .scalaParams
                 .toOption
                 .flatten

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

@@ -87,7 +87,7 @@ object SetupIde extends ScalaCommand[SetupIdeOptions] {
     }
 
   private def buildOptions(opts: SetupIdeOptions): BuildOptions =
-    opts.shared.buildOptions()
+    opts.shared.buildOptions().orExit(opts.shared.logger)
 
   private def writeBspConfiguration(
     options: SetupIdeOptions,

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

@@ -25,7 +25,7 @@ object Test extends ScalaCommand[TestOptions] {
 
   def buildOptions(opts: TestOptions): BuildOptions = {
     import opts._
-    val baseOptions = shared.buildOptions()
+    val baseOptions = shared.buildOptions().orExit(opts.shared.logger)
     baseOptions.copy(
       javaOptions = baseOptions.javaOptions.copy(
         javaOpts =
@@ -63,7 +63,7 @@ object Test extends ScalaCommand[TestOptions] {
 
     val threads = BuildThreads.create()
 
-    val compilerMaker = options.shared.compilerMaker(threads)
+    val compilerMaker = options.shared.compilerMaker(threads).orExit(logger)
 
     val cross = options.compileCross.cross.getOrElse(false)
     val configDb = ConfigDb.open(options.shared.directories.directories)

modules/cli/src/main/scala/scala/cli/commands/bloop/Bloop.scala

@@ -34,7 +34,7 @@ object Bloop extends ScalaCommand[BloopOptions] {
       jvm = opts.jvm,
       coursier = opts.coursier
     )
-    val options = sharedOptions.buildOptions(false, None)
+    val options = sharedOptions.buildOptions(false, None).orExit(opts.logging.logger)
     lazy val defaultJvmCmd =
       sharedOptions.downloadJvm(OsLibc.baseDefaultJvm(OsLibc.jvmIndexOs, "17"), options)
     val javaCmd = opts.compilationServer.bloopJvm

modules/cli/src/main/scala/scala/cli/commands/publish/Publish.scala

@@ -72,7 +72,7 @@ object Publish extends ScalaCommand[PublishOptions] with BuildCommandHelpers {
     mainClass: MainClassOptions,
     ivy2LocalLike: Option[Boolean]
   ): Either[BuildException, BuildOptions] = either {
-    val baseOptions = shared.buildOptions()
+    val baseOptions = shared.buildOptions().orExit(shared.logger)
     val contextualOptions = PublishContextualOptions(
       repository = publishRepo.publishRepository.filter(_.trim.nonEmpty),
       repositoryIsIvy2LocalLike = ivy2LocalLike,
@@ -189,8 +189,8 @@ object Publish extends ScalaCommand[PublishOptions] with BuildCommandHelpers {
     ).orExit(logger)
     val threads = BuildThreads.create()
 
-    val compilerMaker    = options.shared.compilerMaker(threads)
-    val docCompilerMaker = options.shared.compilerMaker(threads, scaladoc = true)
+    val compilerMaker    = options.shared.compilerMaker(threads).orExit(logger)
+    val docCompilerMaker = options.shared.compilerMaker(threads, scaladoc = true).orExit(logger)
 
     val cross = options.compileCross.cross.getOrElse(false)
 

modules/cli/src/main/scala/scala/cli/commands/publish/PublishLocal.scala

@@ -40,8 +40,8 @@ object PublishLocal extends ScalaCommand[PublishLocalOptions] {
     ).orExit(logger)
     val threads = BuildThreads.create()
 
-    val compilerMaker    = options.shared.compilerMaker(threads)
-    val docCompilerMaker = options.shared.compilerMaker(threads, scaladoc = true)
+    val compilerMaker    = options.shared.compilerMaker(threads).orExit(logger)
+    val docCompilerMaker = options.shared.compilerMaker(threads, scaladoc = true).orExit(logger)
 
     val cross = options.compileCross.cross.getOrElse(false)
 

modules/cli/src/main/scala/scala/cli/commands/util/FmtOptionsUtil.scala

@@ -26,7 +26,7 @@ object FmtOptionsUtil {
       (url, !tag0.startsWith("v"))
     }
 
-    def buildOptions: BuildOptions = shared.buildOptions()
+    def buildOptions: BuildOptions = shared.buildOptions().orExit(v.shared.logger)
 
     def scalafmtCliOptions: List[String] =
       scalafmtArg :::

modules/cli/src/main/scala/scala/cli/commands/util/PackageOptionsUtil.scala

@@ -48,7 +48,7 @@ object PackageOptionsUtil {
         .left.map(CompositeBuildException(_))
 
     def baseBuildOptions: BuildOptions = {
-      val baseOptions = shared.buildOptions()
+      val baseOptions = shared.buildOptions().orExit(v.shared.logger)
       baseOptions.copy(
         mainClass = mainClass.mainClass.filter(_.nonEmpty),
         notForBloopOptions = baseOptions.notForBloopOptions.copy(
@@ -120,8 +120,8 @@ object PackageOptionsUtil {
       )
     }
 
-    def compilerMaker(threads: BuildThreads): ScalaCompilerMaker = {
-      val maker = shared.compilerMaker(threads)
+    def compilerMaker(threads: BuildThreads): Either[BuildException, ScalaCompilerMaker] = either {
+      val maker = value(shared.compilerMaker(threads))
       if (forcedPackageTypeOpt.contains(PackageType.DocJar))
         ScalaCompilerMaker.IgnoreScala2(maker)
       else

modules/cli/src/main/scala/scala/cli/commands/util/SharedOptionsUtil.scala

@@ -9,10 +9,11 @@ import dependency.parser.DependencyParser
 
 import java.io.{File, InputStream}
 
+import scala.build.EitherCps.{either, value}
 import scala.build.*
 import scala.build.blooprifle.BloopRifleConfig
 import scala.build.compiler.{BloopCompilerMaker, ScalaCompilerMaker, SimpleScalaCompilerMaker}
-import scala.build.errors.BuildException
+import scala.build.errors.{AmbiguousPlatformError, BuildException}
 import scala.build.interactive.Interactive
 import scala.build.interactive.Interactive.{InteractiveAsk, InteractiveNop}
 import scala.build.internal.CsLoggerUtil.*
@@ -155,11 +156,20 @@ object SharedOptionsUtil extends CommandHelpers {
       enableJmh: Boolean = false,
       jmhVersion: Option[String] = None,
       ignoreErrors: Boolean = false
-    ): bo.BuildOptions = {
-      val platformOpt =
-        if (js.js) Some(Platform.JS)
-        else if (native.native) Some(Platform.Native)
-        else None
+    ): Either[BuildException, bo.BuildOptions] = either {
+      val parsedPlatform = platform.map(Platform.normalize).flatMap(Platform.parse)
+      val platformOpt = value {
+        (parsedPlatform, js.js, native.native) match {
+          case (Some(p: Platform.JS.type), true, false)     => Right(Some(p))
+          case (Some(p: Platform.Native.type), false, true) => Right(Some(p))
+          case (Some(p), _, _) if native.native || js.js    => Left(new AmbiguousPlatformError)
+          case (Some(p), _, _)                              => Right(Some(p))
+          case (None, true, true)                           => Left(new AmbiguousPlatformError)
+          case (None, true, false)                          => Right(Some(Platform.JS))
+          case (None, false, true)                          => Right(Some(Platform.Native))
+          case (None, false, false)                         => Right(None)
+        }
+      }
       bo.BuildOptions(
         scalaOptions = bo.ScalaOptions(
           scalaVersion = scalaVersion
@@ -292,9 +302,8 @@ object SharedOptionsUtil extends CommandHelpers {
       javaCmd
     }
 
-    def bloopRifleConfig(): BloopRifleConfig = {
-
-      val options = buildOptions(false, None)
+    def bloopRifleConfig(): Either[BuildException, BloopRifleConfig] = either {
+      val options = value(buildOptions(false, None))
       lazy val defaultJvmCmd =
         downloadJvm(OsLibc.baseDefaultJvm(OsLibc.jvmIndexOs, "17"), options)
       val javaCmd = compilationServer.bloopJvm.map(downloadJvm(_, options)).orElse {
@@ -315,17 +324,21 @@ object SharedOptionsUtil extends CommandHelpers {
       )
     }
 
-    def compilerMaker(threads: BuildThreads, scaladoc: Boolean = false): ScalaCompilerMaker =
+    def compilerMaker(
+      threads: BuildThreads,
+      scaladoc: Boolean = false
+    ): Either[BuildException, ScalaCompilerMaker] = either {
       if (scaladoc)
         SimpleScalaCompilerMaker("java", Nil, scaladoc = true)
       else if (compilationServer.server.getOrElse(true))
         new BloopCompilerMaker(
-          bloopRifleConfig(),
+          value(bloopRifleConfig()),
           threads.bloop,
           strictBloopJsonCheckOrDefault
         )
       else
         SimpleScalaCompilerMaker("java", Nil)
+    }
 
     def coursierCache = cached(v)(coursier.coursierCache(logging.logger.coursierLogger("")))
 

modules/core/src/main/scala/scala/build/errors/AmbiguousPlatformError.scala

@@ -0,0 +1,5 @@
+package scala.build.errors
+
+final class AmbiguousPlatformError extends BuildException(
+      "Ambiguous platform: more than one type of platform has been passed."
+    )

modules/integration/src/test/scala/scala/cli/integration/RunTestDefinitions.scala

@@ -206,6 +206,24 @@ abstract class RunTestDefinitions(val scalaVersionOpt: Option[String])
     }
   }
 
+  test("simple script JS via platform option") {
+    val message = "Hello"
+    val inputs = TestInputs(
+      os.rel / "simple.sc" ->
+        s"""//> using platform "scala-native"
+           |import scala.scalajs.js
+           |val console = js.Dynamic.global.console
+           |val msg = "$message"
+           |console.log(msg)
+           |""".stripMargin
+    )
+    inputs.fromRoot { root =>
+      val output =
+        os.proc(TestUtil.cli, extraOptions, ".", "--platform", "js").call(cwd = root).out.trim()
+      expect(output == message)
+    }
+  }
+
   def platformNl: String = if (Properties.isWin) "\\r\\n" else "\\n"
 
   def simpleNativeTests(): Unit = {