<?phprequire'vendor/autoload.php';useSymfony\Component\Process\Process;$reference =run_process();echo"Output Reference:\n";echo$reference;echo"\n";for ($i=0;$i <100_000;$i++) {if ($i >0 &&$i %80 ===0) {echo"\n";    }echo'.';$output =run_process();if ($output !==$reference) {echo"\n!!Output changed!!\n";echo"New output:\n";echo"$output\n";exit(1);    }}functionrun_process(){$process =newProcess(['cat',__FILE__]);// If you comment the following line, the test become stable$process->setPty(true);$process->mustRun();return$process->getOutput();}