code: public function initialize()
      {
          if (Filesystem::isLocalPath($this->url)) {
              $this->url = preg_replace('{[\\/]\.git/?$}', '', $this->url);
              $this->repoDir = $this->url;
              $cacheUrl = realpath($this->url);
          } else {
              if (!Cache::isUsable($this->config->get('cache-vcs-dir'))) {
                  throw new \RuntimeException('GitDriver requires a usable cache directory, and it looks like you set it to be disabled');
              }
  
              $this->repoDir = $this->config->get('cache-vcs-dir') . '/' . preg_replace('{[^a-z0-9.]}i', '-', $this->url) . '/';
  
              GitUtil::cleanEnv();
  
              $fs = new Filesystem();
              $fs->ensureDirectoryExists(dirname($this->repoDir));
  
              if (!is_writable(dirname($this->repoDir))) {
                  throw new \RuntimeException('Can not clone '.$this->url.' to access package information. The "'.dirname($this->repoDir).'" directory is not writable by the current user.');
              }
  
              if (preg_match('{^ssh://[^@]+@[^:]+:[^0-9]+}', $this->url)) {
                  throw new \InvalidArgumentException('The source URL '.$this->url.' is invalid, ssh URLs should have a port number after ":".'."\n".'Use ssh://git@example.com:22/path or just git@example.com:path if you do not want to provide a password or custom port.');
              }
  
              $gitUtil = new GitUtil($this->io, $this->config, $this->process, $fs);
              if (!$gitUtil->syncMirror($this->url, $this->repoDir)) {
                  $this->io->writeError('<error>Failed to update '.$this->url.', package information from this repository may be outdated</error>');
              }
  
              $cacheUrl = $this->url;
          }
  
          $this->getTags();
          $this->getBranches();
  
          $this->cache = new Cache($this->io, $this->config->get('cache-repo-dir').'/'.preg_replace('{[^a-z0-9.]}i', '-', $cacheUrl));
      }
docs: {@inheritDoc}