lib/Twig/lib/Twig/Extension/Escaper.php
public function getDefaultStrategy($name)
    {
        // disable string callables to avoid calling a function named html or js,
        // or any other upcoming escaping strategy
        if (!is_string($this->defaultStrategy) && false !== $this->defaultStrategy) {
            return call_user_func($this->defaultStrategy, $name);
        }

        return $this->defaultStrategy;
    }
public function getDefaultStrategy($name)
    {
        // disable string callables to avoid calling a function named html or js,
        // or any other upcoming escaping strategy
        if (!is_string($this->defaultStrategy) && false !== $this->defaultStrategy) {
            return call_user_func($this->defaultStrategy, $name);
        }

        return $this->defaultStrategy;
    }
Gets the default strategy to use when not defined by the user.

@param string $name The template name

@return string|false The default strategy to use for the template