Symfony\Upgrade\Fixer::addFixer PHP Method

    public function addFixer(FixerInterface $fixer)
    {
        $this->fixers[] = $fixer;
    }

 /**
  * @dataProvider provideFixer
  */
 public function testThatFixSuccessfully(Fixer $fixer)
 {
     $fixer->addFixer(new ProgressBarFixer());
     $fixer->addFixer(new PropertyAccessFixer());
     $changed = $fixer->fix(true);
     $this->assertCount(1, $changed);
     $this->assertCount(2, $changed[$this->getPath()]);
 }