nikic/php-parser                     v4.10.2            A PHP parser written in PHP  

use PhpParser\Error;
use PhpParser\NodeDumper;
use PhpParser\ParserFactory;
use PhpParser\BuilderFactory;
use PhpParser\PrettyPrinter;
use PhpParser\Node;
use PhpParser\Node\Stmt\If_;

$factor = new BuilderFactory;
        $node = $factor->namespace('Name\Space')
            ->addStmt(
                $factor->class('SomeClass')
                ->addStmt($factor->method('check')
                ->makeProtected()
                ->addParam($factor->param('orderData'))
                ->addStmt(
                    new If_($factor->var('result'), [
                        'stmts' => array(
                            new Node\Expr\Print_(new Node\Expr\Variable('someParam'))
                        )
                    ])
                    )))
            ->getNode();
        $stmts = array($node);
        $prettyPrinter = new PrettyPrinter\Standard();
        echo $prettyPrinter->prettyPrintFile($stmts);

<?php

namespace Name\Space;

class SomeClass
{
    protected function check($orderData)
    {
        if ($result) {
            print $someParam
        }
    }
}