public function testIsInternalReferrer()
 {
     // reset referrer
     unset($_SERVER['HTTP_REFERER']);
     $this->assertTrue(SpoonFilter::isInternalReferrer());
     // new referrer
     $_SERVER['HTTP_REFERER'] = 'http://www.spoon-library.com/about-us';
     $_SERVER['HTTP_HOST'] = 'spoon-library.com';
     $this->assertTrue(SpoonFilter::isInternalReferrer(array('spoon-library.com')));
     // multiple domains
     $this->assertTrue(SpoonFilter::isInternalReferrer(array('docs.spoon-library.com', 'blog.spoon-library.com', 'spoon-library.com')));
     // incorrect!
     $this->assertFalse(SpoonFilter::isInternalReferrer(array('rotten.com')));
     $this->assertFalse(SpoonFilter::isInternalReferrer(array('rotten.com', 'rotn.com')));
 }