Allow to use positional commands instead of required options

Author: jchyb

build.sbt

@@ -1,6 +1,6 @@
 scalaVersion := "2.12.15"
 val nativeVersion = "0.4.1"
-val cliVersion = nativeVersion
+val cliVersion = nativeVersion + "-SNAPSHOT"
 
 inThisBuild(
   Def.settings(
@@ -10,16 +10,16 @@ inThisBuild(
 )
 
 lazy val cli = project
-  .in(file(s"cli/version_${nativeVersion}"))
+  .in(file(s"cli"))
   .settings(
     moduleName := "scala-native-cli",
     scalacOptions += "-Ywarn-unused:imports",
     libraryDependencies += "org.scala-native" %% "tools" % nativeVersion,
-    libraryDependencies += "com.github.alexarchambault" %% "case-app" % "2.1.0-M9",
+    libraryDependencies += "com.github.alexarchambault" %% "case-app" % "2.1.0-M10",
     libraryDependencies += "org.scalatest" %% "scalatest" % "3.1.1" % Test,
     assembly / assemblyJarName := "scala-native-cli.jar", // Used for integration tests.
-    Compile / unmanagedSourceDirectories += baseDirectory.value.getParentFile / "shared/src/main/scala",
-    Test / unmanagedSourceDirectories += baseDirectory.value.getParentFile / "shared/src/test/scala"
+    Compile / unmanagedSourceDirectories += baseDirectory.value / s"version_${nativeVersion}/src/main/scala",
+    Test / unmanagedSourceDirectories += baseDirectory.value / s"version_${nativeVersion}/src/test/scala"
   )
 
 // Meant to resolve classpath dependencies, provide compiled nir

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

@@ -0,0 +1,23 @@
+package scala.scalanative.cli
+
+import scala.scalanative.build.Build
+import scala.scalanative.util.Scope
+import scala.scalanative.cli.utils.ConfigConverter
+import scala.scalanative.cli.utils.NativeConfigParserImplicits._
+import scala.scalanative.cli.options.CliOptions
+import caseapp.core.app.CaseApp
+import caseapp.core.RemainingArgs
+
+object ScalaNativeCli extends CaseApp[CliOptions] {
+
+  def run(options: CliOptions, args: RemainingArgs) = {
+    val positionalArgs = args.all 
+    val buildOptionsMaybe = ConfigConverter.convert(options, positionalArgs)
+
+    buildOptionsMaybe.map { buildOptions =>
+      Scope { implicit scope =>
+        Build.build(buildOptions.config, buildOptions.outpath)
+      }
+    }
+  }
+}

cli/shared/src/test/scala/scala/scalanative/cli/ArgParserTest.scala

@@ -2,8 +2,9 @@ package scala.scalanative.cli.options
 
 import caseapp._
 
-@AppName("Scala Native Cli")
+@AppName("ScalaNativeCli")
 @ProgName("scala-native-cli")
+@ArgsName("main] [nir-files")
 case class CliOptions(
     @Recurse
     config: ConfigOptions,

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

@@ -10,16 +10,6 @@ case class ConfigOptions(
     @ValueDescription("<output-path>")
     outpath: String = "scala-native-out",
     @Group("Config")
-    @HelpMessage(
-      "Required sequence of all linked NIR files. Should include the standard Scala Native libraries."
-    )
-    @ValueDescription("<colon-separated-file-paths>")
-    classPath: String,
-    @Group("Config")
-    @HelpMessage("Required entry point for linking.")
-    @ValueDescription("<main-class>")
-    main: String,
-    @Group("Config")
     @HelpMessage("Scala Native working directory. [.]")
     @ValueDescription("<path-to-directory>")
     workdir: String = "."