Fail export with a meaningful message if --test is passed

Author: Gedochao

modules/cli/src/main/scala/scala/cli/commands/export0/Export.scala

@@ -136,6 +136,14 @@ object Export extends ScalaCommand[ExportOptions] {
   override def sharedOptions(opts: ExportOptions): Option[SharedOptions] = Some(opts.shared)
 
   override def runCommand(options: ExportOptions, args: RemainingArgs, logger: Logger): Unit = {
+    if options.scope.test then {
+      logger.error(
+        s"""Including the test scope sources together with the main scope is currently not supported.
+           |Note that test scope sources will still be exported as per the output build tool tests definition demands.""".stripMargin
+      )
+      sys.exit(1)
+    }
+
     val initialBuildOptions = buildOptionsOrExit(options)
 
     val output                   = options.output.getOrElse("dest")

modules/cli/src/main/scala/scala/cli/commands/export0/ExportOptions.scala

@@ -8,6 +8,7 @@ import scala.cli.commands.shared.{
   HelpGroup,
   HelpMessages,
   MainClassOptions,
+  ScopeOptions,
   SharedOptions
 }
 import scala.cli.commands.tags
@@ -83,7 +84,10 @@ final case class ExportOptions(
   @Name("o")
   @Group(HelpGroup.BuildToolExport.toString)
   @Tag(tags.restricted)
-    output: Option[String] = None
+    output: Option[String] = None,
+
+  @Recurse
+    scope: ScopeOptions = ScopeOptions()
 ) extends HasSharedOptions
 // format: on
 object ExportOptions {

website/docs/reference/cli-options.md

@@ -1534,7 +1534,7 @@ Run scalafix rule(s) explicitly, overriding the configuration file default.
 
 Available in commands:
 
-[`compile`](./commands.md#compile), [`doc`](./commands.md#doc), [`package`](./commands.md#package), [`publish`](./commands.md#publish), [`publish local`](./commands.md#publish-local), [`repl` , `console`](./commands.md#repl), [`run`](./commands.md#run), [`shebang`](./commands.md#shebang)
+[`compile`](./commands.md#compile), [`doc`](./commands.md#doc), [`export`](./commands.md#export), [`package`](./commands.md#package), [`publish`](./commands.md#publish), [`publish local`](./commands.md#publish-local), [`repl` , `console`](./commands.md#repl), [`run`](./commands.md#run), [`shebang`](./commands.md#shebang)
 
 <!-- Automatically generated, DO NOT EDIT MANUALLY -->
 

website/docs/reference/commands.md

@@ -116,7 +116,7 @@ The `export` sub-command is experimental.
 Please bear in mind that non-ideal user experience should be expected.
 If you encounter any bugs or have feedback to share, make sure to reach out to the maintenance team at https://github.com/VirtusLab/scala-cli
 
-Accepts option groups: [benchmarking](./cli-options.md#benchmarking-options), [compilation server](./cli-options.md#compilation-server-options), [coursier](./cli-options.md#coursier-options), [debug](./cli-options.md#debug-options), [dependency](./cli-options.md#dependency-options), [export](./cli-options.md#export-options), [global suppress warning](./cli-options.md#global-suppress-warning-options), [help group](./cli-options.md#help-group-options), [input](./cli-options.md#input-options), [jvm](./cli-options.md#jvm-options), [logging](./cli-options.md#logging-options), [main class](./cli-options.md#main-class-options), [markdown](./cli-options.md#markdown-options), [power](./cli-options.md#power-options), [python](./cli-options.md#python-options), [Scala.js](./cli-options.md#scalajs-options), [Scala Native](./cli-options.md#scala-native-options), [scalac](./cli-options.md#scalac-options), [scalac extra](./cli-options.md#scalac-extra-options), [semantic db](./cli-options.md#semantic-db-options), [shared](./cli-options.md#shared-options), [snippet](./cli-options.md#snippet-options), [source generator](./cli-options.md#source-generator-options), [suppress warning](./cli-options.md#suppress-warning-options), [verbosity](./cli-options.md#verbosity-options), [version](./cli-options.md#version-options), [workspace](./cli-options.md#workspace-options)
+Accepts option groups: [benchmarking](./cli-options.md#benchmarking-options), [compilation server](./cli-options.md#compilation-server-options), [coursier](./cli-options.md#coursier-options), [debug](./cli-options.md#debug-options), [dependency](./cli-options.md#dependency-options), [export](./cli-options.md#export-options), [global suppress warning](./cli-options.md#global-suppress-warning-options), [help group](./cli-options.md#help-group-options), [input](./cli-options.md#input-options), [jvm](./cli-options.md#jvm-options), [logging](./cli-options.md#logging-options), [main class](./cli-options.md#main-class-options), [markdown](./cli-options.md#markdown-options), [power](./cli-options.md#power-options), [python](./cli-options.md#python-options), [Scala.js](./cli-options.md#scalajs-options), [Scala Native](./cli-options.md#scala-native-options), [scalac](./cli-options.md#scalac-options), [scalac extra](./cli-options.md#scalac-extra-options), [scope](./cli-options.md#scope-options), [semantic db](./cli-options.md#semantic-db-options), [shared](./cli-options.md#shared-options), [snippet](./cli-options.md#snippet-options), [source generator](./cli-options.md#source-generator-options), [suppress warning](./cli-options.md#suppress-warning-options), [verbosity](./cli-options.md#verbosity-options), [version](./cli-options.md#version-options), [workspace](./cli-options.md#workspace-options)
 
 ## fix