Uncaught ReferenceError: process is not defined (NOT react-error-overlay)

[EnoahNetzach]

Describe the bug

Using the optional chaining operator with process (process?.env) throws a ReferenceError stating that process is not defined.

I originally encountered this behaviour because a dependency is using that syntax, then I tried to write the same in my code and it still breaks.

Note that process.env works, and it doesn't appear to be a problem with react-error-overlay (I also tried to use this fix without success).

A workaround is to add the following in index.tsx:

if (!('process' in window)) {
  // @ts-ignore
  window.process = {}
}

Did you try recovering your dependencies?

I just freshly installed it from scratch using

yarn create react-app temp-app --template typescript

Which terms did you search for in User Guide?

https://github.com/facebook/create-react-app/issues?q=is%3Aissue+uncaught+referenceError%3A+process+is+not+defined
https://github.com/facebook/create-react-app/issues?q=is%3Aissue+process+is+not+defined

Environment

Environment Info:

  current version of create-react-app: 5.0.0
  running from ~/.npm/_npx/c67e74de0542c87c/node_modules/create-react-app

  System:
    OS: macOS 12.2.1
    CPU: (12) x64 Intel(R) Core(TM) i7-9750H CPU @ 2.60GHz
  Binaries:
    Node: 16.12.0 - ~/.nvm/versions/node/v16.12.0/bin/node
    Yarn: 1.22.15 - ~/.nvm/versions/node/v16.12.0/bin/yarn
    npm: 8.1.0 - ~/.nvm/versions/node/v16.12.0/bin/npm
  Browsers:
    Chrome: 99.0.4844.83
    Edge: Not Found
    Firefox: Not Found
    Safari: 15.3
  npmPackages:
    react: ^17.0.2 => 17.0.2 
    react-dom: ^17.0.2 => 17.0.2 
    react-scripts: 5.0.0 => 5.0.0 
  npmGlobalPackages:
    create-react-app: Not Found

Steps to reproduce

1. Install CRA yarn create react-app temp-app --template typescript
2. Add {process?.env?.NODE_ENV} in App.tsx (e.g. in the <p>)

Expected behavior

development is shown

Actual behavior

blank page, the following error in the browser console

Reproducible demo

https://github.com/EnoahNetzach/create-react-app-no-process

[masterbater]

I also encountered this. This is not a bug but intended behavior
https://stackoverflow.com/questions/41359504/webpack-bundle-js-uncaught-referenceerror-process-is-not-defined

. Downgrade to react-scripts@4 or just detach your project and add the config on webpack

[EnoahNetzach]

Thanks @masterbater for the answer, but that looks like a different issue, since cra does provide (some of) the env variables through webpack's DefinePlugin.

Indeed process.env.NODE_ENV does work, the issue I'm encountering is with the optional chaining operator.

I am getting this error by simply using destructuring in an export.

export const {
  REACT_APP_ABC = "ABC",
  REACT_APP_XYZ = "XYZ",
} = process.env;

It doesn't matter if you destructure or use optional chaining, this error just happens whenever you access process outside of a React component as far as I can see.

[Klingefjord]

I'm getting this too

[masterbater]

You can read how to set env for react. If the cause is a plugin fork it or ask the author to update it

…

On Sun, Sep 4, 2022, 6:14 AM Oliver Klingefjord, ***@***.***> wrote: I'm getting this too — Reply to this email directly, view it on GitHub <#12212 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AGI6VFHSCQCRW7VIDQM4FO3V4PETJANCNFSM5R2IFIFQ> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[lovetingyuan]

this is so stupid... can not believe react team could make such mistake...

[SourceCipher]

We are trying to update some libraries and we are getting this issue. Tried to add this

  "overrides": {
    "react-error-overlay": "6.0.9"
  }

to package.json and do a clean install, but no changes. We cant update react-scripts as it will crash whole project. How is this an issue?

[enoguchi-lmi]

this issue happens on a clean installation of CRA 5.0.1 whether trying to use process inside the component or not. None of the proposed solutions worked for me including using react error overlay 6.0.9 or yarn

[abhi-dasgupta]

tried everything else, but still stuck with this exact issue