protected function checkForDuplicateNames()
    {
        $normalized = [];

        foreach ($this->data->rawData['modules'] as $moduleId => $module) {
            $normalized[ $moduleId ] = $this->normalizeName(
                array_get($module, 'prefixed_name') ?: $module['name']
            );
        }

        return $this->getKeysForDuplicates($normalized);
    }