/**
  * @param string $packageName
  * @return string
  */
 protected function getPackagePath($packageName)
 {
     if ($this->packageManager === null) {
         return '';
     }
     if (strpos($packageName, '/') !== false) {
         $packageName = $this->packageManager->getPackageKeyFromComposerName($packageName);
     }
     if (!$this->packageManager->isPackageActive($packageName)) {
         return '';
     }
     return $this->packageManager->getPackage($packageName)->getPackagePath();
 }