Contao\CoreBundle\EventListener\MergeHttpHeadersListener::addMultiHeader PHP Метод

    public function addMultiHeader($name)
    {
        $uniqueKey = $this->getUniqueKey($name);
        if (!in_array($uniqueKey, $this->multiHeaders)) {
            $this->multiHeaders[] = $uniqueKey;
        }
    }

 /**
  * Tests that multi-value headers can be added and removed.
  */
 public function testAddingAndRemovingMultiHeaders()
 {
     $listener = new MergeHttpHeadersListener($this->mockContaoFramework());
     $this->assertEquals($listener->getMultiHeaders(), ['set-cookie', 'link', 'vary', 'pragma', 'cache-control']);
     $listener->removeMultiHeader('cache-control');
     $this->assertEquals($listener->getMultiHeaders(), ['set-cookie', 'link', 'vary', 'pragma']);
     $listener->addMultiHeader('dummy');
     $this->assertEquals($listener->getMultiHeaders(), ['set-cookie', 'link', 'vary', 'pragma', 'dummy']);
     $listener->setMultiHeader(['set-cookie', 'link', 'vary', 'pragma', 'cache-control']);
     $this->assertEquals($listener->getMultiHeaders(), ['set-cookie', 'link', 'vary', 'pragma', 'cache-control']);
 }