Flarum\Locale\Translator::getCatalogue PHP Method

    public function getCatalogue($locale = null)
    {
        if (null === $locale) {
            $locale = $this->getLocale();
        } else {
            $this->assertValidLocale($locale);
        }
        $parse = !isset($this->catalogues[$locale]);
        $catalogue = parent::getCatalogue($locale);
        if ($parse) {
            $this->parseCatalogue($catalogue);
            $fallbackCatalogue = $catalogue;
            while ($fallbackCatalogue = $fallbackCatalogue->getFallbackCatalogue()) {
                $this->parseCatalogue($fallbackCatalogue);
            }
        }
        return $catalogue;
    }