Sometimes we need a Promise which can be resolved, rejected on anywhere else but inside Promise. In Javascript this can be done easily (but not sure properly?)
Also we might wonder if a Promise can be aborted before any resolving or rejection happen, e.g. cancel a http request, or rollback a process with a bunch of async await inside. Aborting is another way to complete a Promise (we cannot leave this Promise pending after aborting or there might be a memory leak), but others who catch this Promise might need to distinguish whether it's been rejected or be aborted (abort means it cannot be resolved). So there should be a new kind of Error when a Promise is aborted, which lead us to catch in case. And the status of this Promise can be described as 'aborted'.