Neos\Flow\ResourceManagement\PersistentResource::getMediaType PHP Метод

    public function getMediaType()
    {
        if ($this->mediaType === null) {
            return Utility\MediaTypes::getMediaTypeFromFilename($this->filename);
        } else {
            return $this->mediaType;
        }
    }

 /**
  * @test
  */
 public function getMediaTypeReturnsMediaTypeBasedOnFileExtension()
 {
     $resource = new PersistentResource();
     $resource->setFilename('file.jpg');
     $this->assertSame('image/jpeg', $resource->getMediaType());
     $resource = new PersistentResource();
     $resource->setFilename('file.zip');
     $this->assertSame('application/zip', $resource->getMediaType());
     $resource = new PersistentResource();
     $resource->setFilename('file.someunknownextension');
     $this->assertSame('application/octet-stream', $resource->getMediaType());
 }