globalPreload docs have non-working code

[bmacnaughton]

Affected URL(s)

https://nodejs.org/docs/latest-v16.x/api/esm.html#globalpreload
https://nodejs.org/docs/latest-v18.x/api/esm.html#globalpreload

Description of the problem

The example code from the docs doesn't work.

port.onmessage doesn't work. the code needs to be port.on('message', ...). Additionally, there is just data, not evt.data.

I know that globalPreload is gone in 20, so feel free to close this. I am working with making loaders work across multiple versions of node and this was a problem that I ran into.

/**
 * This example has the application context send a message to the loader
 * and sends the message back to the application context
 */
export function globalPreload({ port }) {
  port.onmessage = (evt) => {
    port.postMessage(evt.data);
  };
  return `\
    port.postMessage('console.log("I went to the Loader and back");');
    port.onmessage = (evt) => {
      eval(evt.data);
    };
  `;
}

[marco-ippolito]

Thanks for reporting, would you be interested in opening a PR?

[bmacnaughton]

will do

[bmacnaughton]

question: should i submit separate PRs for each version of the docs, a single PR based on a single version of the doc, etc? i'm not sure how to proceed with multiple targets. if the first, do i just use, say, the latest version of 16 to update the v16 docs, then another using the latest versions of 18, etc.

[marco-ippolito]

nope, just a pull request to main with the fix

[targos]

You should submit one PR only, against the highest affected version.
If v21 is affected: PR against main
Otherwise: PR against vN.x-staging, where N is the highest supported and affected version (20 or 18).

[richardlau]

Also note that Node.js 16 is End-of-Life so will not have any new releases.