code: public function doRun(InputInterface $input, OutputInterface $output)
      {
          $stdErr = $output instanceof ConsoleOutputInterface
              ? $output->getErrorOutput()
              : ($input->hasParameterOption('--format', true) && 'txt' !== $input->getParameterOption('--format', null, true) ? null : $output)
          ;
          if (null !== $stdErr) {
              $warningsDetector = new WarningsDetector($this->toolInfo);
              $warningsDetector->detectOldVendor();
              $warningsDetector->detectOldMajor();
              foreach ($warningsDetector->getWarnings() as $warning) {
                  $stdErr->writeln(sprintf($stdErr->isDecorated() ? '<bg=yellow;fg=black;>%s</>' : '%s', $warning));
              }
          }
  
          return parent::doRun($input, $output);
      }
docs: {@inheritdoc}