/**
* @param string $dir The directory to hash
* @throws \InvalidArgumentException If the directory is not readable
*/
public function __construct(string $dir)
{
$this->dir = Fs::dir($dir);
if (!$this->dir->test(Fs::EXISTS | Fs::READABLE)) {
throw new \InvalidArgumentException(sprintf("failed to hash directory; %s", $this->dir->getError()));
}
}
