wrong oder of execution of async

[ivanitskiy]

I was reading this blog: https://v8.dev/blog/fast-async and here is the code they tested:

NJS seems to fall into wrong order of execution:

test.js

if (typeof console === "undefined") {
    global.console = {
        log: function(msg) { ngx.log(ngx.INFO, msg); },
        error: function(msg) { ngx.log(ngx.ERR, msg); },
        warn: function(msg) { ngx.log(ngx.WARN, msg); },
        info: function(msg) { ngx.log(ngx.INFO, msg); },
        debug: function(msg) { ngx.log(ngx.DEBUG, msg); },
    };
}

function hello_world(_r) {
    const p = Promise.resolve();
    (async () => {
        await p;
        console.error('after:await');
    }
    )();
    p.then(() => console.error('after:then'))
        .then(() => console.error('after:then2'));
    return "bar"
}

export default {
    hello_world
}

    server {
        listen 8001;
        js_import test from js/njs.js;
        js_set $js_foo test.hello_world;
        location / {
            return 200 $js_foo;
        }
    }

in the log I see:

2023/11/20 19:03:00 [error] 1#1: *1 js: after:await
2023/11/20 19:03:00 [error] 1#1: *1 js: after:then
2023/11/20 19:03:00 [error] 1#1: *1 js: after:then2

[ivanitskiy]

Chrome 119.0.6045.159:

[drsm]

@ivanitskiy

It's not a bug BTW, 'cause they have fixed the spec.
So now we have a correct order.

[ivanitskiy]

➜  ~ node
Welcome to Node.js v16.15.1.
Type ".help" for more information.
> function hello_world(_r) {
...     const p = Promise.resolve();
...     (async () => {
.....         await p;
.....         console.error('after:await');
.....     }
.....     )();
...     p.then(() => console.error('after:then'))
...         .then(() => console.error('after:then2'));
...     return "bar"
... }
undefined
> hello_world()
'bar'
> after:await
after:then
after:then2

{
  node: '16.15.1',
  v8: '9.4.146.24-node.21',
  uv: '1.43.0',
  zlib: '1.2.11',
  brotli: '1.0.9',
  ares: '1.18.1',
  modules: '93',
  nghttp2: '1.47.0',
  napi: '8',
  llhttp: '6.0.4',
  openssl: '1.1.1o+quic',
  cldr: '40.0',
  icu: '70.1',
  tz: '2021a3',
  unicode: '14.0',
  ngtcp2: '0.1.0-DEV',
  nghttp3: '0.1.0-DEV'
}

[ivanitskiy]

Welcome to Node.js v21.2.0.
Type ".help" for more information.
> function hello_world(_r) {
...     const p = Promise.resolve();
...     (async () => {
...         await p;
...         console.error('after:await');
...     }
...     )();
...     p.then(() => console.error('after:then'))
...         .then(() => console.error('after:then2'));
...     return "bar"
... }
undefined
> hello_world()
'bar'
> after:await
after:then
after:then2

> process.versions
{
  node: '21.2.0',
  acorn: '8.11.2',
  ada: '2.7.2',
  ares: '1.20.1',
  base64: '0.5.1',
  brotli: '1.0.9',
  cjs_module_lexer: '1.2.2',
  cldr: '43.1',
  icu: '73.2',
  llhttp: '9.1.3',
  modules: '120',
  napi: '9',
  nghttp2: '1.58.0',
  nghttp3: '0.7.0',
  ngtcp2: '0.8.1',
  openssl: '3.0.12+quic',
  simdutf: '3.2.18',
  tz: '2023c',
  undici: '5.27.0',
  unicode: '15.0',
  uv: '1.46.0',
  uvwasi: '0.0.19',
  v8: '11.8.172.17-node.15',
  zlib: '1.2.13.1-motley-dfc48fc'
}