Doctrine2 - creating an expression to sanitize parameters to the LIKE clause

ORMExpression.php

<?php
namespace Foo\Core\Doctrine;


use Doctrine\ORM\Query\Expr as DoctrineExpr;

/**
 * Contains custom ORM expressions for comparisons, regexps, case-insensitive matches etc
 * Used instead of the regular Query\Expr() class http://docs.doctrine-project.org/en/2.0.x/reference/query-builder.html#the-expr-class
 */
class Expr extends DoctrineExpr
{
    /**
     * Creates a LIKE clause after escaping all meaningful symbols within the like token (specifically, % _ and \)
     * @return Comparison
     */
    public function sanitizedLike($fieldRef, $searchToken, $prefix = '%', $suffix = '%')
    {
        //escape reserved characters in LIKE [%_\] with the default escape symbol "\"
        $cleanToken      = addcslashes($searchToken, "%_" . chr(92)); //92 = backslash
        $compiledPattern = $prefix . $cleanToken . $suffix;
        return $this->like($fieldRef, $this->literal($compiledPattern));
    }
    
    public function regexp($x, $y)
    {
        //...
    }
}

Repository.php

<?php
 
namespace Foo\Entity;
 
use Doctrine\ORM\EntityRepository;
use Foo\Core\Doctrine\Expr;
 
class ProductRepository extends EntityRepository
{
    /**
     * Find Product entities containing searched terms
     *
     * @param string $term
     * @return Product[]
     */
    public function findInSearchableFields($term)
    {
        $expr = new Expr();
        return $this->createQueryBuilder('p')
            ->andWhere($expr->sanitizedLike('p.title',$term))
            ->getQuery()
            ->execute();
    }
}