ReferenceError: App is not defined

When starting up my dev server with the latest version of next-translate, I ran into this webpack issue:

ReferenceError: App is not defined at eval (webpack-internal:///./pages/_app.js:185:1)

After some debugging, It seems to have something to do with the App.propTypes in the _app.js file, when exporting the App while defining it:

import PropTypes from "prop-types";

export default function App({ Component, pageProps }) {
 return <Component {...pageProps} />
}

App.propTypes = {
  Component: PropTypes.any,
  pageProps: PropTypes.any,
}

I managed to narrow it down to a minimal reproducible example. You can find my repository here.

It’s based on the simple example of the next-translate example directory. Hopefully the comments in the _app.js and next.config.js files are clear enough to reproduce the issue!

[giladaya]

Until a fix is released and in case it helps anyone -

I had a similar issue and found out this can be worked-around by not directly exporting the App component from _app file.

In my case, changing from this:

//...

export default function MyApp({ Component, pageProps }: AppProps) {
  return (
    <ApolloProvider client={client}>
      <Component {...pageProps} />
    </ApolloProvider>
  );
}

to this:

//...

function MyApp({ Component, pageProps }: AppProps) {
  return (
    <ApolloProvider client={client}>
      <Component {...pageProps} />
    </ApolloProvider>
  );
}

export default MyApp

Solved the error.

[aralroca]

@jellebouwman @giladaya @justirva09 @j-schumann The idea of 2.0 version is to change the regular expressions in a better way. Currently, there are 2 proposals: with Babel parser and with TypeScript compiler.

We need feedback from the people to decide which one corrects more errors and does not generate new ones.

This bug should be fixed with the new version Can you test these two prereleases and give feedback?

With Babel: 2.0.0-experimental.1

With TypeScript compiler: 2.0.0-experimental.2

You can use this discussion to write your feedback:

https://github.com/aralroca/next-translate/discussions/881

Thank you so much!