Symfony\Component\HttpFoundation\ResponseHeaderBag::hasCacheControlDirective PHP Method

    public function hasCacheControlDirective($key)
    {
        return array_key_exists($key, $this->computedCacheControl);
    }

 public function testCacheControlHeader()
 {
     $bag = new ResponseHeaderBag(array());
     $this->assertEquals('no-cache', $bag->get('Cache-Control'));
     $this->assertTrue($bag->hasCacheControlDirective('no-cache'));
     $bag = new ResponseHeaderBag(array('Cache-Control' => 'public'));
     $this->assertEquals('public', $bag->get('Cache-Control'));
     $this->assertTrue($bag->hasCacheControlDirective('public'));
     $bag = new ResponseHeaderBag(array('ETag' => 'abcde'));
     $this->assertEquals('private, must-revalidate', $bag->get('Cache-Control'));
     $this->assertTrue($bag->hasCacheControlDirective('private'));
     $this->assertTrue($bag->hasCacheControlDirective('must-revalidate'));
     $this->assertFalse($bag->hasCacheControlDirective('max-age'));
     $bag = new ResponseHeaderBag(array('Expires' => 'Wed, 16 Feb 2011 14:17:43 GMT'));
     $this->assertEquals('private, must-revalidate', $bag->get('Cache-Control'));
     $bag = new ResponseHeaderBag(array('Expires' => 'Wed, 16 Feb 2011 14:17:43 GMT', 'Cache-Control' => 'max-age=3600'));
     $this->assertEquals('max-age=3600, private', $bag->get('Cache-Control'));
     $bag = new ResponseHeaderBag(array('Last-Modified' => 'abcde'));
     $this->assertEquals('private, must-revalidate', $bag->get('Cache-Control'));
     $bag = new ResponseHeaderBag(array('Etag' => 'abcde', 'Last-Modified' => 'abcde'));
     $this->assertEquals('private, must-revalidate', $bag->get('Cache-Control'));
     $bag = new ResponseHeaderBag(array('cache-control' => 'max-age=100'));
     $this->assertEquals('max-age=100, private', $bag->get('Cache-Control'));
     $bag = new ResponseHeaderBag(array('cache-control' => 's-maxage=100'));
     $this->assertEquals('s-maxage=100', $bag->get('Cache-Control'));
     $bag = new ResponseHeaderBag(array('cache-control' => 'private, max-age=100'));
     $this->assertEquals('max-age=100, private', $bag->get('Cache-Control'));
     $bag = new ResponseHeaderBag(array('cache-control' => 'public, max-age=100'));
     $this->assertEquals('max-age=100, public', $bag->get('Cache-Control'));
     $bag = new ResponseHeaderBag();
     $bag->set('Last-Modified', 'abcde');
     $this->assertEquals('private, must-revalidate', $bag->get('Cache-Control'));
 }