Symfony\Component\Finder\Finder::ignoreVCS PHP Method

    public function ignoreVCS($ignoreVCS)
    {
        if ($ignoreVCS) {
            $this->ignore |= static::IGNORE_VCS_FILES;
        } else {
            $this->ignore &= ~static::IGNORE_VCS_FILES;
        }

        return $this;
    }

 protected function ensureProjectRoot()
 {
     if (!($this->rootDir = $this->input->getOption('project-root'))) {
         $this->rootDir = getcwd();
     }
     $this->rootDir = realpath($this->rootDir);
     $this->fs->mkdir($this->rootDir);
     $finder = new Finder();
     $finder->in($this->rootDir);
     $finder->depth(0);
     $finder->ignoreVCS(false);
     $rootFiles = [];
     /** @var SplFileInfo $splInfo */
     foreach ($finder as $splInfo) {
         $rootFiles[] = $splInfo->getFilename();
     }
     $requiredFiles = ['composer.json', 'composer.lock'];
     $requiredDirs = ['vendor'];
     foreach (array_merge($requiredFiles, $requiredDirs) as $file) {
         if (!in_array($file, $rootFiles)) {
             // possibly not root
             $this->output->writeln("<error>You should either run this script under your project root directory, or provide the '--project-root' option.</error>");
             $this->output->writeln("The project root directory should contain at least the following files and directories:");
             foreach ($requiredFiles as $requiredFile) {
                 $this->output->writeln("\t- <comment>{$requiredFile}</comment>");
             }
             foreach ($requiredDirs as $requiredDir) {
                 $this->output->writeln("\t- <comment>{$requiredDir}/</comment>");
             }
             exit(1);
         }
     }
 }