message: Improve the sleep test.
diff: @@ -7,18 +7,37 @@ swoole_runtime: sleep
  require __DIR__ . '/../include/bootstrap.php';
  Swoole\Runtime::enableCoroutine();
  go(function () {
  + // sleep
  + $s = microtime(true);
  + sleep(1);
  + time_approximate(1, microtime(true) - $s);
  sleep(0);
  sleep(-1);
  - usleep(1000);
  +
  + // usleep
  + $s = microtime(true);
  + $t = ms_random(0.01, 0.1);
  + usleep($t * 1000 * 1000);
  + time_approximate($t, microtime(true) - $s);
  + usleep(0);
  + usleep(-1);
  +
  + // time_nanosleep
  time_nanosleep(-1, 1);
  time_nanosleep(0, 1);
  time_nanosleep(0, 1000 * 1000);
  - echo "\nDONE\n";
  });
  +echo "NON-BLOCKED\n";
  +Swoole\Event::wait();
  +echo "\nDONE\n";
  ?>
  --EXPECTF--
  +NON-BLOCKED
  +
  Warning: sleep(): Number of seconds must be greater than or equal to 0 in %s on line %d
  +Warning: usleep(): Number of seconds must be greater than or equal to 0 in %s on line %d
  +
  Warning: time_nanosleep(): The seconds value must be greater than 0 in %s on line %d
  DONE
  