TypeError: Object prototype may only be an Object or null: undefined

[kaiyoma]

I'm currently trying to upgrade my project to webpack 5 and I'm now running into a bizarre compilation error with this package. When I start my app, I see this in the browser console:

TypeError: Object prototype may only be an Object or null: undefined
    at setPrototypeOf (<anonymous>)
    at extendStatics (Streamer.js?fc49:7)
    at __extends (Streamer.js?fc49:10)
    at eval (Streamer.js?fc49:20)
    at eval (Streamer.js?fc49:72)
    at Object../node_modules/.pnpm/csv-string@4.0.1/node_modules/csv-string/dist/Streamer.js (bundle.js:47851)
    at __webpack_require__ (bundle.js:93000)
    at fn (bundle.js:93290)
    at eval (CSV.js?a8d5:4)
    at Object../node_modules/.pnpm/csv-string@4.0.1/node_modules/csv-string/dist/CSV.js (bundle.js:47829)

The error appears to be coming from deep inside csv-string. What does this error mean?

[holub008]

In case it helps, I'm also here with a webpack 5 issue, albeit with a better error message:

[1] ERROR in ./node_modules/csv-string/dist/Streamer.js 33:15-32
[1] Module not found: Error: Can't resolve 'stream' in '{omited}/node_modules/csv-string/dist'
[1] 
[1] BREAKING CHANGE: webpack < 5 used to include polyfills for node.js core modules by default.
[1] This is no longer the case. Verify if you need this module and configure a polyfill for it.

I'm guessing the webpack 5 bump you made removed the stream polyfill that this lib depends on.

I'm probably going to move on to a new CSV writer (easy for my project) unless maintainers have plans to break out a module that doesn't have this dependency?

[andrewdowis]

@kaiyoma @holub008 I am experiencing the same when upgrading webpack 4 to 5, experiencing the error on the package csv-string - were you able to find a solution, alternate package, or anything?

[kaiyoma]

@kaiyoma @holub008 I am experiencing the same when upgrading webpack 4 to 5, experiencing the error on the package csv-string - were you able to find a solution, alternate package, or anything?

I gave up on webpack 5 and stayed with 4, until we migrate to something different entirely. 🤷

[holub008]

There are endless CSV libraries on the npm registry, I haven't migrated yet but can update here when I find & vet one that doesn't rely on system polyfills.

[kaiyoma]

Ha! I just encountered this same problem again while trying to migrate to Vite, and found my old bug. I'm guessing there's still no fix?

[holub008]

Alright, I exaggerated. I didn't end up finding any trustworthy CSV writings libs for the client that didn't require polyfill.

So I moved my spreadsheet needs to the server with exceljs (we run on Node) in order to drop csv-string. Generating CSV on the client was a quick and dirty trick made easy by default polyfills in webpack 4, but let's be honest... it was always a hack! FWIW, exceljs is a breeze to use and produces featureful, styled sheets in a variety of formats.

[holub008]

To addressing your specific need @kaiyoma, I also moved my project to vite (What a shame that CRA maintainers have ghosted it without even a deprecation notice). It looks like adding polyfills should be straightforward: https://www.npmjs.com/package/vite-plugin-node-polyfills

However, I would recommend avoiding polyfills for the sanity of future developers.