PDepend\Engine::addFileFilter PHP Method

    public function addFileFilter(Filter $filter)
    {
        $this->fileFilter->append($filter);
    }

 /**
  * Initializes the accepted php source file extensions.
  *
  * @param \PDepend\Engine $pdepend The context php depend instance.
  * @param PHP_PMD    $phpmd   The calling/parent php mess detector.
  *
  * @return void
  */
 private function initExtensions(Engine $pdepend, PHP_PMD $phpmd)
 {
     if (count($phpmd->getFileExtensions()) > 0) {
         $pdepend->addFileFilter(new ExtensionFilter($phpmd->getFileExtensions()));
     }
 }