BYONM: Dynamically importing CommonJS file from an npm package errors

[bartlomieju]

$ deno run -A npm:create-next-app@latest next-app
$ cd next-app
$ deno run -A --unstable-byonm npm:next dev
error: Uncaught (in promise) ReferenceError: module is not defined
module.exports = nextConfig
^
    at file:///Users/ib/dev/next-app/next.config.js:6:1

Chaging module.exports = to export default fixes the problem.

[Cedar-81]

is this a problem that needs to be fixed on Denos end? (Still new to open source, just trying to understand how it could be fixed)

[dsherret]

I disagree that this is a bug. The file is not located in an npm package. It's located at file:///Users/ib/dev/next-app/next.config.js, which means it is ESM. This can be fixed in next.config.js by changing:

module.exports = nextConfig;

To...

export default nextConfig;

...as Next.js loads this file via a dynamic import. We should update the error message to explain that module.exports = needs to be converted to ESM.