chill-bundles/Templating/ChillTwigHelper.php

<?php
/*
 * 
 */
namespace Chill\MainBundle\Templating;

use Twig\Extension\AbstractExtension;
use Twig\TwigFilter;
use Twig\Environment;

/**
 * 
 */
class ChillTwigHelper extends AbstractExtension
{
    public function getFilters()
    {
        return [
            new TwigFilter('chill_print_or_message', [$this, 'printOrMessage'], [
                'needs_environment' => true,
                'is_safe' => ['html', 'html_attrs']
            ]),
        ];
    }
    
    /**
     * Print `value` inside a template, or, if $value is empty, 
     * print $message.
     * 
     * The template can be customized. The template is a full path to another
     * template, or one of the key belows: 
     * 
     * - 'default' ;
     * - 'blockquote' ;
     * 
     * @param Environment $twig
     * @param string $value
     * @param string $message
     * @param string $template
     * @return string
     */
    public function printOrMessage(
        Environment $twig,
        $value, 
        $message = 'No value', 
        $template = 'default'
    ) {
        switch ($template) {
            case 'default':
            case 'blockquote':
                $t = '@ChillMain/Extensions/PrintOrMessage/'.$template.'.html.twig';
                break;
            default:
                $t = $template;
        }
        
        return $twig->render($t, [
            'value' => $value,
            'message' => $message
        ]);
    }
}