Transforming node:builtin to built-in when targeting commonjs

[aminya]

🙋 feature request

Currently, Parceljs silently uses node:builtin inside commonjs although this doesn't work. There should be a transformer that converts this to normal nodejs imports when targeting commonjs.

import { execFileSync } from "node:fs"

🤔 Expected Behavior

const { execFileSync } = require("fs")

😯 Current Behavior

const { execFileSync } = require("node:fs")

💁 Possible Solution

🔦 Context

💻 Examples

[mischnic]

Another place where node:* specifiers aren't handled yet:

parcel/packages/transformers/js/core/src/fs.rs

Line 54 in bb923d6

if &source == "fs" && &specifier == "readFileSync" {

[aminya]

Where is the code that handles this?

[mischnic]

The resolver is in https://github.com/parcel-bundler/parcel/blob/v2/packages/utils/node-resolver-core/src/NodeResolver.js, search for node: in that file.

But I think there's currently no way for a resolver to say "don't bundle this dependency (so isExcluded: true), but rewrite it from node:fs to fs".

[aminya]

Which option specifies that the target is commonjs? This line should be replaced with something like:

      filename = ifTargetCommonjs ? builtin.replace(/^node:/, "") : builtin;

parcel/packages/utils/node-resolver-core/src/NodeResolver.js

Line 273 in f2d0a3a

filename = builtin;

[aminya]

Found a workaround using Babel using @upleveled/babel-plugin-remove-node-prefix. Add this to the babel config, and it should be transformed automatically:

babel.config.json

{
  "plugins": ["@upleveled/babel-plugin-remove-node-prefix"],
  "sourceMap": "inline"
}

[aminya]

This command can be run after Parcel build:

cross-env NODE_ENV=production babel ./dist/ --out-dir ./dist --source-maps true --plugins @upleveled/babel-plugin-remove-node-prefix --compact --no-babelrc

Unfortunately, Parcel doesn't run babel on the dependencies. I have to use something like that

[aminya]

I noticed that this also doesn't work when targeting the browser. I expect Parcel use the web polyfil for such dependencies, but it instead errors out.

[aminya]

I think it is not fixed

[aminya]

Could you integrate this babel transform into Parcel as the last step?
#8049 (comment)

[mischnic]

So this is causing problems on Node <14.18.0 and Node 12?

[aminya]

Yes, all the old Node versions have this issue.

[aminya]

Not fixed