public function testClosure()
{
$jobby = new Jobby();
$jobby->add('HelloWorldClosure', ['command' => static function () {
echo 'A function!';
return true;
}, 'schedule' => '* * * * *', 'output' => $this->logFile]);
$jobby->run();
// Job runs asynchronously, so wait a bit
sleep($this->getSleepTime());
$this->assertEquals('A function!', $this->getLogContent());
}