Launcher fix: let the polyglot options to be processed by the polyglot launcher

com.oracle.truffle.r.launcher/src/com/oracle/truffle/r/launcher/RCmdOptions.java

@@ -64,7 +64,6 @@ public final class RCmdOptions {
     }
 
     public enum RCmdOption {
-        HELP(RCmdOptionType.BOOLEAN, true, "h", "help", false, "Print short help message and exit"),
         VERSION(RCmdOptionType.BOOLEAN, true, "version", false, "Print version info and exit"),
         ENCODING(RCmdOptionType.STRING, false, "encoding=ENC", null, "Specify encoding to be used for stdin"),
         SAVE(RCmdOptionType.BOOLEAN, true, "save", false, "Do save workspace at the end of the session"),

com.oracle.truffle.r.launcher/src/com/oracle/truffle/r/launcher/RscriptCommand.java

@@ -31,6 +31,7 @@ import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 
+import org.graalvm.options.OptionCategory;
 import org.graalvm.polyglot.PolyglotException;
 import org.graalvm.polyglot.Source;
 
@@ -52,13 +53,11 @@ public final class RscriptCommand extends RAbstractLauncher {
     }
 
     @Override
-    protected List<String> preprocessArguments(List<String> arguments, Map<String, String> polyglotOptions) {
-        List<String> unrecognizedArgs = super.preprocessArguments(arguments, polyglotOptions);
+    protected void validateArguments(Map<String, String> polyglotOptions) {
         try {
             this.rScriptArguments = preprocessRScriptOptions(options);
-            return unrecognizedArgs;
         } catch (PrintHelp e) {
-            return Collections.singletonList("--help");
+            printHelp(OptionCategory.USER);
         }
     }