various debugging-related fixes

runtime/src/main/java/me/topchetoeu/j2s/runtime/debug/DebugHandler.java

@@ -93,7 +93,7 @@ public interface DebugHandler {
 	}
 	public default FunctionMap getMapOrEmpty(Environment env, FunctionValue func) {
 		if (func instanceof CodeFunction codeFunc) return getMapOrEmpty(env, codeFunc.body);
-		else return null;
+		else return FunctionMap.EMPTY;
 	}
 
 	public static DebugHandler get(Environment exts) {

runtime/src/main/java/me/topchetoeu/j2s/runtime/values/objects/ArrayLikeValue.java

@@ -195,7 +195,6 @@ public abstract class ArrayLikeValue extends ObjectValue {
 				res.add("    " + line);
 			}
 		}
-		res.set(res.size() - 1, res.getLast().substring(0, res.getLast().length() - 1));
 		res.add("]");
 
 		return res;