Function safeUnref

packages/core/src/utils/timer.ts:10–15

(timer: ReturnType<typeof setTimeout>)

 * do not support `unref`.
 */
export function safeUnref(timer: ReturnType<typeof setTimeout>): ReturnType<typeof setTimeout> {
  if (typeof timer === 'object' && typeof timer.unref === 'function') {
    timer.unref();
  }
  return timer;
}