src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/parser/Parser.java

*** 4389,4402 ****
                  return new UnaryNode(unaryToken, expr);
              }
              appendStatement(new ExpressionStatement(unaryLine, unaryToken, finish, expr));
              return LiteralNode.newInstance(unaryToken, finish, true);
          }
          case VOID:
          case TYPEOF:
-         case ADD:
-         case SUB:
          case BIT_NOT:
          case NOT:
              next();
              final Expression expr = unaryExpression();
              return new UnaryNode(unaryToken, expr);
--- 4389,4407 ----
                  return new UnaryNode(unaryToken, expr);
              }
              appendStatement(new ExpressionStatement(unaryLine, unaryToken, finish, expr));
              return LiteralNode.newInstance(unaryToken, finish, true);
          }
+         case ADD:
+         case SUB: {
+             final TokenType opType = type;
+             next();
+             final Expression expr = unaryExpression();
+             return new UnaryNode(Token.recast(unaryToken, (opType == TokenType.ADD) ? TokenType.POS : TokenType.NEG), expr);
+         }
          case VOID:
          case TYPEOF:
          case BIT_NOT:
          case NOT:
              next();
              final Expression expr = unaryExpression();
              return new UnaryNode(unaryToken, expr);