Cannot resolve babel module when using react-scripts@next

[nloding]

Is this a bug report?

Yes, for react-scripts 2.0. (edit: originally I had believed this to be related to workspaces, but after more testing, it is not - this happens without a monorepo/workspaces. All details below updated to reflect that with a simpler test case.)

Did you try recovering your dependencies?

Yes. I deleted both the workspace and CRA app node_modules and lock files, and reinstalled with yarn (v1.6.0); deleted everything again and tried with npm (v5.6.0) with the same result.

Which terms did you search for in User Guide?

I followed the steps outlined in the roadmap for react-scripts 2.0 to initialize the app.

Environment

MacOS High Sierra 10.134
node 10.1.0
yarn 1.6.0
create-react-app@next
react-scripts@2.0.0-next.66cc7a90

I executed this command to init a new CRA2 app:
npx create-react-app@next --scripts-version=2.0.0-next.66cc7a90 test

Steps to Reproduce

1. Create a CRA2 app with the command above in the packages (or, in my example, "exercises" folder)
2. In the App.js file, attempt to import getPrototypeOf from @babel/runtime/helpers/getPrototypeOf
3. Run yarn start in either the CRA2 app or the workspace root

(Note: I discovered this issue originally when I installed semantic-ui-react and attempted to use one of its components, which resulted in this error. To simplify the demo I just attempted to import getPrototypeOf in App.js.)

Expected Behavior

CRA app compiles and runs

Actual Behavior

A compilation error occurs:
Module not found: Can't resolve '@babel/runtime/helpers/getPrototypeOf' in '/Users/nloding/code/oss/cra2-workspace-broken-ref/src'

I also see this warning when installing the dependencies, I am unsure if it is related?
npm WARN @babel/plugin-syntax-dynamic-import@7.0.0-beta.34 requires a peer of @babel/core@7.0.0-beta.34 but none is installed. You must install peer dependencies yourself.

Reproducible Demo

https://github.com/nloding/cra2-workspace-broken-ref

The broken line: https://github.com/nloding/cra2-workspace-broken-ref/blob/master/src/App.js#L6

[nloding]

It looks like react-scripts@2.0.0-next.66cc7a90 references @babel/runtime@7.0.0-beta.44 which is, in fact, missing getPrototypeOf. However, even if you manually install @babel/runtime@7.0.0-beta.47, which does have the missing export, the compilation still fails. I've updated my repo to reference beta.47.

❯ cat node_modules/@babel/runtime/helpers/getPrototypeOf.js | head -n 1
var _Object$getPrototypeOf = require("../core-js/object/get-prototype-of");

❯ cat node_modules/@babel/runtime/package.json | grep version
  "version": "7.0.0-beta.47",

❯ npm start
...
./src/App.js
Module not found: Can't resolve '@babel/runtime/helpers/getPrototypeOf' in '/Users/nloding/code/oss/cra2-workspace-broken-ref/src'

[bugzpodder]

When the new alpha of CRA releases with babel 7b46+ you should be fine. Internally react-scripts webpack resolves babel runtime relative to itself.

https://github.com/facebook/create-react-app/blob/next/packages/react-scripts/config/webpack.config.dev.js#L152

[nloding]

Got it, thanks - I'll keep an eye out for the next alpha announcement and test it out.

[Ethorsen]

This is starting to be a real problem as more and more packages rely on getPrototypeOf. We need to hold back a lot of upgrades because of the outdated version of babel in react-scripts@next

[bugzpodder]

I've personally had a similar issue as well. The good news is babel 7 is almost out (rc4) and I am sure there will be a new version of 2.0.0@next with it once it has been released.

[venikx]

@Ethorsen Same here.
I need Jest 22, but I can't update CRA to @next, because some deps rely on getPrototypeOf and breaks my app.

@bugzpodder How do you suggest installing and updating the next version of CRA? npm i ?

[nloding]

@Ethorsen @bugzpodder @AnaRobynn the latest cut of react-scripts (react-scripts@2.0.0-next.a671462c) uses 7.0.0-beta.46 which has getPrototypeOf. You can use that version of react-scripts in the mean time, it works. There are upgrade directions in the roadmap issue #3815

[venikx]

I will try that one out when I get the chance, thank you! I might have fucked up some step, due to beinf the end of the day and lack of sleep.

Tomorrow is another day!