lib/Twig/Loader/Themes.php
public function findFile($name, $relative = true)
    {
        if ($this->refFindTemplate === null) {
            $this->refFindTemplate = new ReflectionMethod('Twig_Loader_Filesystem', 'findTemplate');
            $this->refFindTemplate->setAccessible(true);
        }

        $name = $this->prepareName($name);
        $path = $this->refFindTemplate->invoke($this->fsloader, $name);
        return $relative ? ltrim(str_replace($this->basePath, '', $path), DIRECTORY_SEPARATOR) : $path;
    }
public function findFile($name, $relative = true)
    {
        if ($this->refFindTemplate === null) {
            $this->refFindTemplate = new ReflectionMethod('Twig_Loader_Filesystem', 'findTemplate');
            $this->refFindTemplate->setAccessible(true);
        }

        $name = $this->prepareName($name);
        $path = $this->refFindTemplate->invoke($this->fsloader, $name);
        return $relative ? ltrim(str_replace($this->basePath, '', $path), DIRECTORY_SEPARATOR) : $path;
    }
Find resource file path.

@param string $name
@param bool   $relative

@return string