code: public function doDownload(PackageInterface $package, $path, $url)
      {
          SvnUtil::cleanEnv();
          $ref = $package->getSourceReference();
  
          $repo = $package->getRepository();
          if ($repo instanceof VcsRepository) {
              $repoConfig = $repo->getRepoConfig();
              if (array_key_exists('svn-cache-credentials', $repoConfig)) {
                  $this->cacheCredentials = (bool) $repoConfig['svn-cache-credentials'];
              }
          }
  
          $this->io->writeError(" Checking out ".$package->getSourceReference());
          $this->execute($url, "svn co", sprintf("%s/%s", $url, $ref), null, $path);
      }
docs: {@inheritDoc}