Add a --version option with compile-time SN version value embeddal

Author: jchyb

build.sbt

@@ -1,8 +1,8 @@
 scalaVersion := "2.12.15"
 
-// TODO remove and settle for one version after release
+// TODO remove and settle for one newest after release
 val nativeVersion = sys.env.get("SN_CLI_VERSION") match {
-  case Some(value) => "0.4.1"
+  case Some(value) => value
   case None        => "0.4.0"
 }
 val versionTag =
@@ -20,14 +20,17 @@ inThisBuild(
 )
 
 lazy val cli = project
-  .in(file(s"cli"))
+  .in(file("cli"))
+  .enablePlugins(BuildInfoPlugin)
   .settings(
     moduleName := "scala-native-cli",
     scalacOptions += "-Ywarn-unused:imports",
     libraryDependencies += "org.scala-native" %% "tools" % nativeVersion,
     libraryDependencies += "com.github.alexarchambault" %% "case-app" % "2.1.0-M10",
     libraryDependencies += "org.scalatest" %% "scalatest" % "3.1.1" % Test,
     assembly / assemblyJarName := "scala-native-cli.jar", // Used for integration tests.
+    buildInfoKeys := Seq[BuildInfoKey]("nativeVersion" -> nativeVersion),
+    buildInfoPackage := "scala.scalanative.cli.options",
     Compile / unmanagedSourceDirectories += baseDirectory.value / s"version_${versionTag}/src/main/scala",
     Test / unmanagedSourceDirectories += baseDirectory.value / s"version_${versionTag}/src/test/scala"
   )

cli/src/main/scala/scala/scalanative/cli/ScalaNativeCli.scala

@@ -7,16 +7,25 @@ import scala.scalanative.cli.utils.NativeConfigParserImplicits._
 import scala.scalanative.cli.options.CliOptions
 import caseapp.core.app.CaseApp
 import caseapp.core.RemainingArgs
+import scala.scalanative.cli.options.BuildInfo
 
 object ScalaNativeCli extends CaseApp[CliOptions] {
 
   def run(options: CliOptions, args: RemainingArgs) = {
-    val positionalArgs = args.all
-    val buildOptionsMaybe = ConfigConverter.convert(options, positionalArgs)
+    if (options.misc.version) {
+      println(BuildInfo.nativeVersion)
+    } else {
+      println(scala.scalanative.cli.options.BuildInfo.nativeVersion)
+      val positionalArgs = args.all
+      val buildOptionsMaybe = ConfigConverter.convert(options, positionalArgs)
 
-    buildOptionsMaybe.map { buildOptions =>
-      Scope { implicit scope =>
-        Build.build(buildOptions.config, buildOptions.outpath)
+      buildOptionsMaybe match {
+        case Left(thrown) => 
+          System.err.println(thrown.getMessage()) 
+        case Right(buildOptions) => 
+          Scope { implicit scope =>
+            Build.build(buildOptions.config, buildOptions.outpath)
+          }
       }
     }
   }

cli/src/main/scala/scala/scalanative/cli/options/CliOptions.scala

@@ -11,5 +11,7 @@ case class CliOptions(
     @Recurse
     nativeConfig: NativeConfigOptions,
     @Recurse
-    logger: LoggerOptions
+    logger: LoggerOptions,
+    @Recurse
+    misc: MiscOptions
 )

cli/src/main/scala/scala/scalanative/cli/options/MiscOptions.scala

@@ -0,0 +1,10 @@
+package scala.scalanative.cli.options
+
+import caseapp.HelpMessage
+import caseapp.Group
+
+case class MiscOptions(
+  @Group("Help")
+  @HelpMessage("Print scala-native-cli version and exit")
+  val version: Boolean = false
+)

cli/src/test/scala/scala/scalanative/cli/ConfigConverterTest.scala

@@ -11,19 +11,22 @@ import scala.scalanative.build.GC
 import scala.scalanative.cli.utils.NativeConfigParserImplicits
 import scala.scalanative.build.Mode
 import scala.scalanative.build.LTO
+import scala.scalanative.cli.options.MiscOptions
 
 class ConfigConverterTest extends AnyFlatSpec {
   val dummyLoggerOptions = LoggerOptions()
   val dummyNativeConfigOptions = NativeConfigOptions()
   val dummyConfigOptions = ConfigOptions()
+  val dummyMiscOptions = MiscOptions()
 
   val dummyArguments =
     Seq("$Main", "A.nir", "B.nir")
 
   val dummyCliOptions = CliOptions(
     config = dummyConfigOptions,
     nativeConfig = dummyNativeConfigOptions,
-    logger = dummyLoggerOptions
+    logger = dummyLoggerOptions,
+    misc = dummyMiscOptions
   )
 
   "ArgParser" should "parse default options" in {
@@ -70,7 +73,8 @@ class ConfigConverterTest extends AnyFlatSpec {
         NativeConfigOptions(gc =
           NativeConfigParserImplicits.gcParser(None, gcString).right.get
         ),
-        dummyLoggerOptions
+        dummyLoggerOptions,
+        dummyMiscOptions
       )
       val config =
         ConfigConverter.convert(options, dummyArguments).right.get.config
@@ -89,7 +93,8 @@ class ConfigConverterTest extends AnyFlatSpec {
         NativeConfigOptions(mode =
           NativeConfigParserImplicits.modeParser(None, modeString).right.get
         ),
-        dummyLoggerOptions
+        dummyLoggerOptions,
+        dummyMiscOptions
       )
       val config =
         ConfigConverter.convert(options, dummyArguments).right.get.config
@@ -107,7 +112,8 @@ class ConfigConverterTest extends AnyFlatSpec {
         NativeConfigOptions(lto =
           NativeConfigParserImplicits.ltoParser(None, ltoString).right.get
         ),
-        dummyLoggerOptions
+        dummyLoggerOptions,
+        dummyMiscOptions
       )
       val config =
         ConfigConverter.convert(options, dummyArguments).right.get.config
@@ -131,7 +137,8 @@ class ConfigConverterTest extends AnyFlatSpec {
         clang = Some(clangString),
         clangPP = Some(clangPPString)
       ),
-      dummyLoggerOptions
+      dummyLoggerOptions,
+      dummyMiscOptions
     )
 
     val nativeConfig =

cli/version_0.4.0/src/main/scala/scala/scalanative/cli/options/NativeVersion.scala

@@ -1 +1,2 @@
 addSbtPlugin("com.eed3si9n" % "sbt-assembly" % "1.0.0")
+addSbtPlugin("com.eed3si9n" % "sbt-buildinfo" % "0.10.0")

cli/version_newer/src/main/scala/scala/scalanative/cli/options/NativeVersion.scala

@@ -16,7 +16,7 @@ object ScalaNativeCliTestRunnerPlugin extends AutoPlugin {
   object autoImport {
     val nativeVersion = System.getProperty("scala-native-cli-native-version")
 
-    val runTest = inputKey[Unit](
+    val runCli = inputKey[Unit](
       "Runs scala-native-cli with classpath and selected other options via cli arguments"
     )
   }

project/plugins.sbt

@@ -30,7 +30,7 @@ object TestRunnerPluginInternal {
       inConfig(Compile)(configSettings)
 
   lazy val configSettings: Seq[Setting[_]] = Seq(
-    runTest := {
+    runCli := {
       val args = spaceDelimited("<arg>").parsed
 
       val classpath = fullClasspath.value.map(_.data.toString())