src/Modules/Assets/AssetsCollection.php
public function dumpCompress($assets_dir)
    {
        $filters = [];
        if ($this->assets[0]->getType() === 'js') {
            $filters[] = new PackerFilter();
        } else {
            $filters[] = new CssMinFilter();
        }

        return $this->dump($assets_dir, $filters);
    }
public function dumpCompress($assets_dir)
    {
        $filters = [];
        if ($this->assets[0]->getType() === 'js') {
            $filters[] = new PackerFilter();
        } else {
            $filters[] = new CssMinFilter();
        }

        return $this->dump($assets_dir, $filters);
    }
@param string $assets_dir

@return string