Fix SubCommand varAgrs tabComplete

SpigotCore_Main/src/de/steamwar/command/SubCommand.java

@@ -19,6 +19,7 @@
 
 package de.steamwar.command;
 
+import org.bukkit.Bukkit;
 import org.bukkit.command.CommandSender;
 
 import java.lang.reflect.InvocationTargetException;
@@ -26,6 +27,7 @@ import java.lang.reflect.Method;
 import java.lang.reflect.Parameter;
 import java.util.*;
 import java.util.function.Function;
+import java.util.logging.Level;
 
 class SubCommand {
 
@@ -95,6 +97,7 @@ class SubCommand {
         } catch (IllegalArgumentException | IllegalAccessException e) {
             throw new SecurityException(e.getMessage(), e);
         } catch (InvocationTargetException | RuntimeException e) {
+            Bukkit.getLogger().log(Level.INFO, e.getMessage(), e);
             return false;
         }
         return true;
@@ -126,7 +129,9 @@ class SubCommand {
                 String s = argsList.remove(0);
                 if (argsList.isEmpty()) return arguments[arguments.length - 1].tabCompletes(commandSender, Arrays.copyOf(args, args.length - 1), s);
                 try {
-                    arguments[arguments.length - 1].map(s);
+                    if (arguments[arguments.length - 1].map(s) == null) {
+                        return Collections.emptyList();
+                    }
                 } catch (Exception e) {
                     return Collections.emptyList();
                 }