code: public function deploy()
      {
          $pullRequest = getenv('TRAVIS_PULL_REQUEST');
          $branch = getenv('TRAVIS_BRANCH');
  
          if ((int) $pullRequest >= 1) {
              die('Not deploying pull requests.' . PHP_EOL);
          }
  
          if (!array_key_exists($branch, $this->branches)) {
              die('Branch ' . $branch . ' has no environment to deploy to.' . PHP_EOL);
          }
  
          $environment = $this->branches[$branch];
  
          echo 'Downloading Deployer.phar...' . PHP_EOL;
          passthru('wget http://deployer.org/deployer.phar');
  
          echo 'Deploying...' . PHP_EOL;
          $deployCommand = 'php deployer.phar deploy';
          $deployCommand .= ' ' . $environment;
          $deployCommand .= $this->verbose ? ' -vvv' : '';
          passthru($deployCommand);
      }
docs: Deploy to the configured branch