code: protected function execute($command, $url)
      {
          if (null === $this->util) {
              $this->util = new SvnUtil($this->baseUrl, $this->io, $this->config, $this->process);
              $this->util->setCacheCredentials($this->cacheCredentials);
          }
  
          try {
              return $this->util->execute($command, $url);
          } catch (\RuntimeException $e) {
              if (null === $this->util->binaryVersion()) {
                  throw new \RuntimeException('Failed to load '.$this->url.', svn was not found, check that it is installed and in your PATH env.' . "\n\n" . $this->process->getErrorOutput());
              }
  
              throw new \RuntimeException(
                  'Repository '.$this->url.' could not be processed, '.$e->getMessage()
              );
          }
      }
docs: Execute an SVN command and try to fix up the process with credentials
  if necessary.
  
  @param  string            $command The svn command to run.
  @param  string            $url     The SVN URL.
  @throws \RuntimeException
  @return string