presto-parser/src/main/java/io/prestosql/sql/ExpressionFormatter.java/Formatter/visitArithmeticUnary
class Formatter:        @Override
        protected String visitArithmeticUnary(ArithmeticUnaryExpression node, Void context)
        {
            String value = process(node.getValue(), context);

            switch (node.getSign()) {
                case MINUS:
                    // Unary is ambiguous with respect to negative numbers. "-1" parses as a number, but "-(1)" parses as "unaryMinus(number)"
                    // The parentheses are needed to ensure the parsing roundtrips properly.
                    return "-(" + value + ")";
                case PLUS:
                    return "+" + value;
                default:
                    throw new UnsupportedOperationException("Unsupported sign: " + node.getSign());
            }
        }