timers: allow promisified timeouts/immediates to be canceled

[jasnell]

Using the new experimental AbortController...

const{ promisify }=require('util');constsleep=promisify(setTimeout);constac=newAbortController();constsignal=ac.signal;sleep(1000,undefined,{ signal });ac.abort();// cancels the setTimeout and rejects the Promise

const{ promisify }=require('util');constimmediate=promisify(setImmediate);constac=newAbortController();constsignal=ac.signal;immediate(undefined,{ signal });ac.abort();// cancels the setImmediate and rejects the Promise

This will necessarily be experimental for as long as AbortController is experimental.

Signed-off-by: James M Snell jasnell@gmail.com

Checklist

• make -j4 test (UNIX), or vcbuild test (Windows) passes
• tests and/or benchmarks are included
• documentation is changed or added
• commit message follows commit guidelines

[mcollina]

I like this. However I think it's time we design a few new apis for setImmediate and setTimeout that are both promisified from the start and abortable.

I do promisify(setTimeout) too many times already.

On a technical side this would have the benefit of avoiding to call promisify to change the AbortController

[jasnell]

I've been considered exporting the promisified versions of setTimeout and setImmediate as a separate namespace off timers such that we could do...

const{
setTimeout,
setImmediate
}=require('timers/promises');

I'm also considering a promisified version of setInterval that returns an async iterator such that...

const{
setInterval,}=require('timers/promises');(async()=>{forawait(constnofsetInterval(1000)){console.log('tick...')}})()

We also need to consider how to ref/unref promisified timers/intervals/immediates.

[jasnell]

@mcollina ... I will introduce require('timers/promises') in a separate PR

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/31896/

[addaleax]

Nice :)

[mcollina]

lgtm

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/31922/

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/31925/

[jasnell]

Landed in bfbdc84

[codebytere]

Marking dont-land since #33527 is semver-major