Add help parameter to print specific options for ScalaNative and Scal…

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

@@ -1,7 +1,7 @@
 package scala.cli
 
 import caseapp.core.app.CommandsEntryPoint
-import caseapp.core.help.RuntimeCommandsHelp
+import caseapp.core.help.{Help, RuntimeCommandsHelp}
 
 import java.io.{ByteArrayOutputStream, PrintStream}
 import java.nio.charset.StandardCharsets
@@ -40,16 +40,17 @@ object ScalaCli extends CommandsEntryPoint {
     Version
   )
 
-  lazy val progName                 = (new Argv0).get("scala-cli")
-  override def description          = "Compile, run, package Scala code."
+  lazy val progName = (new Argv0).get("scala-cli")
+  override def description =
+    "Scala CLI is a command-line tool to interact with the Scala language. It lets you compile, run, test, and package your Scala code."
+  override def summaryDesc =
+    "See 'scala-cli <command> --help' to read about a specific subcommand. To see full help run 'scala-cli <command> --help-full'."
   final override def defaultCommand = Some(actualDefaultCommand)
 
   // FIXME Report this in case-app default NameFormatter
   override lazy val help: RuntimeCommandsHelp = {
     val parent = super.help
-    parent.withDefaultHelp(
-      parent.defaultHelp.withNameFormatter(actualDefaultCommand.nameFormatter)
-    )
+    parent.withDefaultHelp(Help[Unit]())
   }
 
   override def enableCompleteCommand    = true

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

@@ -11,6 +11,7 @@ import scala.concurrent.Await
 import scala.concurrent.duration.Duration
 
 object Bsp extends ScalaCommand[BspOptions] {
+  override def hidden = true
   def run(options: BspOptions, args: RemainingArgs): Unit = {
     CurrentParams.verbosity = options.shared.logging.verbosity
     if (options.shared.logging.verbosity >= 3)

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

@@ -11,6 +11,7 @@ object Compile extends ScalaCommand[CompileOptions] {
   override def group                                  = "Main"
   override def sharedOptions(options: CompileOptions) = Some(options.shared)
   def run(options: CompileOptions, args: RemainingArgs): Unit = {
+    maybePrintGroupHelp(options)
     CurrentParams.verbosity = options.shared.logging.verbosity
     val inputs = options.shared.inputsOrExit(args)
     CurrentParams.workspaceOpt = Some(inputs.workspace)

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

@@ -8,7 +8,7 @@ import scala.cli.CurrentParams
 import scala.cli.internal.FetchExternalBinary
 
 object Fmt extends ScalaCommand[FmtOptions] {
-  override def group                              = "Miscellaneous"
+  override def group                              = "Main"
   override def sharedOptions(options: FmtOptions) = Some(options.shared)
   override def names = List(
     List("fmt"),

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

@@ -0,0 +1,35 @@
+package scala.cli.commands
+
+import caseapp._
+import caseapp.core.help.Help
+import upickle.default.{ReadWriter, macroRW}
+
+import scala.cli.ScalaCli
+
+@HelpMessage("Print help message")
+case class HelpGroupOptions(
+  @HelpMessage("Show options for ScalaJS")
+  helpJs: Boolean = false,
+  @HelpMessage("Show options for ScalaNative")
+  helpNative: Boolean = false
+) {
+
+  private def printHelpWithGroup(help: Help[_], group: String) = {
+    println(help.help(ScalaCli.helpFormat.withHiddenGroups(
+      ScalaCli.helpFormat.hiddenGroups.map(_.filterNot(_ == group))
+    )))
+    sys.exit(0)
+  }
+
+  def maybePrintGroupHelp(help: Help[_]): Unit = {
+    if (helpJs) printHelpWithGroup(help, "Scala.JS")
+    else if (helpNative) printHelpWithGroup(help, "Scala Native")
+  }
+}
+
+object HelpGroupOptions {
+  lazy val parser: Parser[HelpGroupOptions]                           = Parser.derive
+  implicit lazy val parserAux: Parser.Aux[HelpGroupOptions, parser.D] = parser
+  implicit lazy val help: Help[HelpGroupOptions]                      = Help.derive
+  implicit lazy val jsonCodec: ReadWriter[HelpGroupOptions]           = macroRW
+}

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

@@ -11,7 +11,8 @@ import scala.cli.CurrentParams
 import scala.cli.internal.FetchExternalBinary
 
 object Metabrowse extends ScalaCommand[MetabrowseOptions] {
-  override def group = "Miscellaneous"
+  override def hidden = true
+  override def group  = "Miscellaneous"
   override def names = List(
     List("browse"),
     List("metabrowse")

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

@@ -34,6 +34,7 @@ object Package extends ScalaCommand[PackageOptions] {
   override def group                                  = "Main"
   override def sharedOptions(options: PackageOptions) = Some(options.shared)
   def run(options: PackageOptions, args: RemainingArgs): Unit = {
+    maybePrintGroupHelp(options)
     CurrentParams.verbosity = options.shared.logging.verbosity
     val inputs = options.shared.inputsOrExit(args)
     CurrentParams.workspaceOpt = Some(inputs.workspace)

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

@@ -54,7 +54,7 @@ final case class PackageOptions(
     pkg: Boolean = false,
   @Group("Package")
   @HelpMessage("Build Docker image")
-    docker: Boolean = false,
+    docker: Boolean = false
 ) {
   // format: on
   def packageTypeOpt: Option[PackageType] =

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

@@ -17,13 +17,15 @@ object Run extends ScalaCommand[RunOptions] {
 
   override def sharedOptions(options: RunOptions) = Some(options.shared)
 
-  def run(options: RunOptions, args: RemainingArgs): Unit =
+  def run(options: RunOptions, args: RemainingArgs): Unit = {
+    maybePrintGroupHelp(options)
     run(
       options,
       args.remaining,
       args.unparsed,
       () => Inputs.default()
     )
+  }
 
   def run(
     options: RunOptions,

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

@@ -84,6 +84,11 @@ abstract class ScalaCommand[T](implicit parser: Parser[T], help: Help[T])
         parent.argument(prefix, state)
     }
   }
+
+  def maybePrintGroupHelp(options: T): Unit =
+    for (shared <- sharedOptions(options))
+      shared.helpGroups.maybePrintGroupHelp(help)
+
   override def helpFormat =
     HelpFormat.default()
       .withSortedGroups(Some(Seq(
@@ -101,6 +106,10 @@ abstract class ScalaCommand[T](implicit parser: Parser[T], help: Help[T])
         "Miscellaneous",
         ""
       )))
+      .withHiddenGroups(Some(Seq(
+        "Scala.JS",
+        "Scala Native"
+      )))
       .withTerminalWidthOpt {
         if (Properties.isWin)
           if (coursier.paths.Util.useJni())

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

@@ -9,7 +9,7 @@ import scala.build.options
 final case class ScalaJsOptions(
 
   @Group("Scala")
-  @HelpMessage("Enable Scala.JS")
+  @HelpMessage("Enable Scala.JS. To show more options for Scala.Js pass `--help-js`")
     js: Boolean = false,
 
   @Group("Scala.JS")

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

@@ -9,7 +9,7 @@ import scala.build.options
 final case class ScalaNativeOptions(
 
   @Group("Scala")
-  @HelpMessage("Enable Scala Native")
+  @HelpMessage("Enable Scala Native. To show more options for Scala Native pass `--help-native`")
     native: Boolean = false,
 
   @Group("Scala Native")

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

@@ -100,6 +100,8 @@ final case class SharedOptions(
     defaultForbiddenDirectories: Boolean = true,
   @Hidden
     forbid: List[String] = Nil,
+  @Recurse
+  helpGroups: HelpGroupOptions = HelpGroupOptions()
 ) {
   // format: on
 

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

@@ -18,6 +18,7 @@ object Test extends ScalaCommand[TestOptions] {
   private def reset = Console.RESET
 
   def run(options: TestOptions, args: RemainingArgs): Unit = {
+    maybePrintGroupHelp(options)
     CurrentParams.verbosity = options.shared.logging.verbosity
     val inputs = options.shared.inputsOrExit(args)
     CurrentParams.workspaceOpt = Some(inputs.workspace)

modules/cli/src/test/scala/cli/tests/HelpCheck.scala

@@ -0,0 +1,13 @@
+package cli.tests
+
+import scala.cli.ScalaCli
+
+class HelpCheck extends munit.FunSuite {
+
+  test("help message should be shorter then 80 lines") {
+    val helpMessage = ScalaCli.help.help(ScalaCli.helpFormat)
+
+    val lines = helpMessage.split("\r\n|\r|\n").length
+    assert(lines <= 80)
+  }
+}

website/docs/reference/cli-options.md

@@ -362,6 +362,32 @@ Aliases: `--full-help`
 
 Print help message, including hidden options, and exit
 
+## Help group options
+
+Available in commands:
+- [`bsp`](./commands.md#bsp)
+- [`compile`](./commands.md#compile)
+- [`export`](./commands.md#export)
+- [`fmt` / `format` / `scalafmt`](./commands.md#fmt)
+- [`browse` / `metabrowse`](./commands.md#browse)
+- [`package`](./commands.md#package)
+- [`console` / `repl`](./commands.md#console)
+- [`run`](./commands.md#run)
+- [`setup-ide`](./commands.md#setup-ide)
+- [`shebang`](./commands.md#shebang)
+- [`test`](./commands.md#test)
+
+
+<!-- Automatically generated, DO NOT EDIT MANUALLY -->
+
+#### `--help-js`
+
+Show options for ScalaJS
+
+#### `--help-native`
+
+Show options for ScalaNative
+
 ## Install completions options
 
 Available in commands:
@@ -779,7 +805,7 @@ Available in commands:
 
 #### `--js`
 
-Enable Scala.JS
+Enable Scala.JS. To show more options for Scala.Js pass `--help-js`
 
 #### `--js-version`
 
@@ -823,7 +849,7 @@ Available in commands:
 
 #### `--native`
 
-Enable Scala Native
+Enable Scala Native. To show more options for Scala Native pass `--help-native`
 
 #### `--native-version`