Allow to cross-compile in run / repl / package

A single Scala version and platform ends up being used for run / repl /
package, but --cross allows to compile for all Scala versions and
platforms prior to running / repl / packaging.

Author: alexarchambault

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

@@ -0,0 +1,15 @@
+package scala.cli.commands
+
+import caseapp._
+
+// format: off
+final case class CompileCrossOptions(
+  @HelpMessage("Cross-compile sources")
+    cross: Option[Boolean] = None
+)
+// format: on
+
+object CompileCrossOptions {
+  implicit val parser = Parser[CompileCrossOptions]
+  implicit val help   = Help[CompileCrossOptions]
+}

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

@@ -51,13 +51,15 @@ object Package extends ScalaCommand[PackageOptions] {
     val bloopRifleConfig    = options.shared.bloopRifleConfig()
     val logger              = options.shared.logger
 
+    val cross = options.compileCross.cross.getOrElse(false)
+
     if (options.watch.watch) {
       val watcher = Build.watch(
         inputs,
         initialBuildOptions,
         bloopRifleConfig,
         logger,
-        crossBuilds = false,
+        crossBuilds = cross,
         postAction = () => WatchUtil.printWatchMessage()
       ) {
         case (s: Build.Successful, _) =>
@@ -70,7 +72,7 @@ object Package extends ScalaCommand[PackageOptions] {
     }
     else {
       val (build, _) =
-        Build.build(inputs, initialBuildOptions, bloopRifleConfig, logger, crossBuilds = false)
+        Build.build(inputs, initialBuildOptions, bloopRifleConfig, logger, crossBuilds = cross)
       build match {
         case s: Build.Successful =>
           doPackage(inputs, logger, options.output.filter(_.nonEmpty), options.force, s)

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

@@ -13,6 +13,8 @@ final case class PackageOptions(
     shared: SharedOptions = SharedOptions(),
   @Recurse
     watch: SharedWatchOptions = SharedWatchOptions(),
+  @Recurse
+    compileCross: CompileCrossOptions = CompileCrossOptions(),
 
   @Group("Package")
   @HelpMessage("Set destination path")

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

@@ -57,6 +57,8 @@ object Repl extends ScalaCommand[ReplOptions] {
             sys.exit(1)
       }
 
+    val cross = options.compileCross.cross.getOrElse(false)
+
     if (inputs.isEmpty) {
       val artifacts = initialBuildOptions.artifacts(logger)
       maybeRunRepl(initialBuildOptions, artifacts, None, allowExit = !options.watch.watch)
@@ -72,7 +74,7 @@ object Repl extends ScalaCommand[ReplOptions] {
         initialBuildOptions,
         bloopRifleConfig,
         logger,
-        crossBuilds = false,
+        crossBuilds = cross,
         postAction = () => WatchUtil.printWatchMessage()
       ) { (build, _) =>
         maybeRunRepl(build.options, build.artifacts, build.outputOpt, allowExit = false)
@@ -82,7 +84,7 @@ object Repl extends ScalaCommand[ReplOptions] {
     }
     else {
       val (build, _) =
-        Build.build(inputs, initialBuildOptions, bloopRifleConfig, logger, crossBuilds = false)
+        Build.build(inputs, initialBuildOptions, bloopRifleConfig, logger, crossBuilds = cross)
       maybeRunRepl(build.options, build.artifacts, build.outputOpt, allowExit = true)
     }
   }

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

@@ -14,6 +14,8 @@ final case class ReplOptions(
     sharedJava: SharedJavaOptions = SharedJavaOptions(),
   @Recurse
     watch: SharedWatchOptions = SharedWatchOptions(),
+  @Recurse
+    compileCross: CompileCrossOptions = CompileCrossOptions(),
 
   @Group("Repl")
   @HelpMessage("Use Ammonite rather than the default Scala REPL")

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

@@ -39,13 +39,15 @@ object Run extends ScalaCommand[RunOptions] {
         jvmRunner = build.options.addRunnerDependency.getOrElse(true)
       )
 
+    val cross = options.compileCross.cross.getOrElse(false)
+
     if (options.watch.watch) {
       val watcher = Build.watch(
         inputs,
         initialBuildOptions,
         bloopRifleConfig,
         logger,
-        crossBuilds = false,
+        crossBuilds = cross,
         postAction = () => WatchUtil.printWatchMessage()
       ) {
         case (s: Build.Successful, _) =>
@@ -58,7 +60,7 @@ object Run extends ScalaCommand[RunOptions] {
     }
     else {
       val (build, _) =
-        Build.build(inputs, initialBuildOptions, bloopRifleConfig, logger, crossBuilds = false)
+        Build.build(inputs, initialBuildOptions, bloopRifleConfig, logger, crossBuilds = cross)
       build match {
         case s: Build.Successful =>
           maybeRun(s, allowTerminate = true)

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

@@ -20,6 +20,8 @@ final case class RunOptions(
     sharedJava: SharedJavaOptions = SharedJavaOptions(),
   @Recurse
     watch: SharedWatchOptions = SharedWatchOptions(),
+  @Recurse
+    compileCross: CompileCrossOptions = CompileCrossOptions(),
 
   @Group("Runner")
   @HelpMessage("Specify which main class to run")

website/docs/reference/cli-options.md

@@ -104,6 +104,20 @@ Aliases: `-p`, `--classpath`
 
 Print resulting class path
 
+## Compile cross options
+
+Available in commands:
+- [`package`](./commands#package)
+- [`console` / `repl`](./commands#console)
+- [`run`](./commands#run)
+
+
+<!-- Automatically generated, DO NOT EDIT MANUALLY -->
+
+#### `--cross`
+
+Cross-compile sources
+
 ## Coursier options
 
 Available in commands:

website/docs/reference/commands.md

@@ -81,6 +81,7 @@ Fire-up a Scala REPL
 
 Accepts options:
 - [compilation server](./cli-options.md#compilation-server-options)
+- [compile cross](./cli-options.md#compile-cross-options)
 - [coursier](./cli-options.md#coursier-options)
 - [dependency](./cli-options.md#dependency-options)
 - [java](./cli-options.md#java-options)
@@ -99,6 +100,7 @@ Compile and package Scala code
 
 Accepts options:
 - [compilation server](./cli-options.md#compilation-server-options)
+- [compile cross](./cli-options.md#compile-cross-options)
 - [coursier](./cli-options.md#coursier-options)
 - [dependency](./cli-options.md#dependency-options)
 - [jvm](./cli-options.md#jvm-options)
@@ -121,6 +123,7 @@ scala-cli MyApp.scala -- first-arg second-arg
 Accepts options:
 - [benchmarking](./cli-options.md#benchmarking-options)
 - [compilation server](./cli-options.md#compilation-server-options)
+- [compile cross](./cli-options.md#compile-cross-options)
 - [coursier](./cli-options.md#coursier-options)
 - [dependency](./cli-options.md#dependency-options)
 - [java](./cli-options.md#java-options)