/** * @inheritDoc * * @throws FormatterException * If $classes does not implement the correct interface, * or does not have a quality value. */ protected function assertValid(array $classes) { parent::assertValid($classes); foreach ($classes as $formatter => $quality) { if (!is_subclass_of($formatter, FormatterInterface::class)) { throw FormatterException::invalidClass($formatter); } if (!is_float($quality)) { throw FormatterException::needsQuality($formatter); } } }