/**
* {@inheritDoc}
* Additionally, checks if extension has changed
*
* @throws \RuntimeException
*/
public function setFileName($fileName)
{
$hasFilename = $this->fileName !== null;
if ($hasFilename) {
$previousName = $this->fileName;
$previousExtension = $this->getExtension();
}
parent::setFileName($fileName);
if ($hasFilename) {
$newExtension = $this->getExtension();
if (strcasecmp($previousExtension, $newExtension) !== 0) {
// restore name back to previous one. Because that's safer.
parent::setFileName($previousName);
throw new \RuntimeException('Extension change is not allowed');
}
}
}
