Parcel as React Library bundler

[diego-hourly]

I've bee trying to use the setup suggested by the website for libraries (https://parceljs.org/getting-started/library/) but including react in the process to create a React library component. But keep getting errors. First

> parcel watch

🚨 Build failed.

@parcel/core: Failed to resolve '@parcel/transformer-react-refresh-wrap/lib/helpers/helpers.js' from
'./node_modules/@parcel/transformer-react-refresh-wrap/lib/ReactRefreshWrapTransformer.js'

@parcel/resolver-default: External dependency "@parcel/transformer-react-refresh-wrap" is not declared in package.json.

And after including @parcel/transformer-react-refresh-wrap as a dependency

> parcel watch

🚨 Build failed.

@parcel/packager-js: Asset was skipped or not found.

  AssertionError [ERR_ASSERTION]: Asset was skipped or not found.
  at ScopeHoistingPackager.getSymbolResolution

Not sure why is not able to parse jsx in watch mode.

Here are the 2 files I have in place

{
  "name": "@poc/commons",
  "version": "1.0.0",
  "description": "",
  "source": "src/index.js",
  "module": "dist/module.js",
  "scripts": {
    "watch": "parcel watch",
    "build": "parcel build"
  },
  "devDependencies": {
    "parcel": "^2.0.1"
  },
  "dependencies": {
    "@parcel/transformer-react-refresh-wrap": "^2.0.1"
  },
  "peerDependencies": {
    "react": "^17.0.2",
    "react-dom": "^17.0.2"
  }
}

// src/index.js

export const Button = ({ children }) => <button>{children}</button>;

NOTE: running parcel build works. It's watch mode the one that fails

[diego-hourly]

It was my fault. Parcel doesn't support "Arrow function expressions" by default. Including a .babelrc with

{
  "presets": ["react-app"]
}

solves my issue.

[e-krebs]

FYI, I filed a bug on that issue, as we shouldn't have to use babel to build a React library: #7652

[mattmogford]

Did the big get resolved? I'm getting this exact issue today