Symfony2/Twig: how to tell the custom twig tag to NOT escape the output

Question

I created a custom tag which should work like that:

{{ thumbnail(image.fullPath,620) }}

unfortunately I have to use it like that

{{ thumbnail(image.fullPath,620)|raw }}

Is there a way to unescape directly in the twig extension?

My extension registers the thumbnail code like this:

 public function getFunctions()
    {
        return array(
            'thumbnail' => new \Twig_Function_Method($this, 'thumbnail'),
        );
    }

Answer 1

The third argument of Twig_Function_Method::__construct() is an array of options for the function. One of these options is is_safe which specifies whether function outputs "safe" HTML/JavaScript code:

public function getFunctions()
{
    return array(
        'thumbnail' => new \Twig_Function_Method($this, 'thumbnail', array(
            'is_safe' => array('html')
        ))
    );
}

Answer 2

Crozin's answer is correct but because \Twig_Function_Method is now deprecated you can use \Twig_SimpleFunction as such:

return [
    new \Twig_SimpleFunction('thumbnail', [$this, 'thumbnail'], [
        'is_safe' => ['html']
    ]),
];