PHPUnit_Framework_TestSuite::injectFilter PHP Method

    public function injectFilter(PHPUnit_Runner_Filter_Factory $filter)
    {
        $this->iteratorFilter = $filter;
        foreach ($this as $test) {
            if ($test instanceof self) {
                $test->injectFilter($filter);
            }
        }
    }

 private function processSuiteFilters(PHPUnit_Framework_TestSuite $suite, array $arguments)
 {
     if (!$arguments['filter'] && empty($arguments['groups']) && empty($arguments['excludeGroups'])) {
         return;
     }
     $filterFactory = new PHPUnit_Runner_Filter_Factory();
     if (!empty($arguments['excludeGroups'])) {
         $filterFactory->addFilter(new ReflectionClass('PHPUnit_Runner_Filter_Group_Exclude'), $arguments['excludeGroups']);
     }
     if (!empty($arguments['groups'])) {
         $filterFactory->addFilter(new ReflectionClass('PHPUnit_Runner_Filter_Group_Include'), $arguments['groups']);
     }
     if ($arguments['filter']) {
         $filterFactory->addFilter(new ReflectionClass('PHPUnit_Runner_Filter_Test'), $arguments['filter']);
     }
     $suite->injectFilter($filterFactory);
 }