Unknown helper createSuper... Error!!

[asimhafeezz]

i just updated my project with next from 9.1 to 9.3 with it's latest version and got this problem.
how can i solve it?

[ error ] ./node_modules/next/dist/client/index.js
ReferenceError: D:\code\project\webapp\node_modules\next\dist\client\index.js: Unknown helper createSuper
[ event ] build page: /next/dist/pages/_error
[ wait ]  compiling ...
[ error ] ./node_modules/next/dist/client/index.js
ReferenceError: D:\code\project\webapp\node_modules\next\dist\client\index.js: Unknown helper createSuper
Error: Cannot find module 'D:\code\project\webapp\.next\build-manifest.json'
Require stack:
- D:\code\project\webapp\node_modules\next\dist\next-server\server\load-components.js
- D:\code\project\webapp\node_modules\next\dist\next-server\server\api-utils.js
- D:\code\project\webapp\node_modules\next\dist\next-server\server\next-server.js
- D:\code\project\webapp\node_modules\next\dist\server\next.js
- D:\code\project\webapp\node_modules\next\dist\server\lib\start-server.js
- D:\code\project\webapp\node_modules\next\dist\cli\next-dev.js
- D:\code\project\webapp\node_modules\next\dist\bin\next
    at Function.Module._resolveFilename (internal/modules/cjs/loader.js:954:17)
    at Function.Module._load (internal/modules/cjs/loader.js:847:27)
    at Module.require (internal/modules/cjs/loader.js:1016:19)
    at require (internal/modules/cjs/helpers.js:69:18)
    at Object.loadComponents (D:\code\project\webapp\node_modules\next\dist\next-server\server\load-components.js:29:9)
    at DevServer.findPageComponents (D:\code\project\webapp\node_modules\next\dist\next-server\server\next-server.js:522:60)    
    at DevServer.renderErrorToHTML (D:\code\project\webapp\node_modules\next\dist\next-server\server\next-server.js:816:33)     
    at DevServer.renderErrorToHTML (D:\code\project\webapp\node_modules\next\dist\server\next-dev-server.js:15:811)
    at runMicrotasks (<anonymous>)
    at processTicksAndRejections (internal/process/task_queues.js:93:5)
    at async DevServer.render (D:\code\project\webapp\node_modules\next\dist\next-server\server\next-server.js:507:22)
    at async Object.fn (D:\code\project\webapp\node_modules\next\dist\next-server\server\next-server.js:366:17)
    at async Router.execute (D:\code\project\webapp\node_modules\next\dist\next-server\server\router.js:137:32)
    at async DevServer.run (D:\code\project\webapp\node_modules\next\dist\next-server\server\next-server.js:480:29)
    at async DevServer.handleRequest (D:\code\project\webapp\node_modules\next\dist\next-server\server\next-server.js:133:20) { 
  code: 'MODULE_NOT_FOUND',
  requireStack: [
    'D:\\code\\project\\webapp\\node_modules\\next\\dist\\next-server\\server\\load-components.js',
    'D:\\code\\project\\webapp\\node_modules\\next\\dist\\next-server\\server\\api-utils.js',
    'D:\\code\\project\\webapp\\node_modules\\next\\dist\\next-server\\server\\next-server.js',
    'D:\\code\\project\\webapp\\node_modules\\next\\dist\\server\\next.js',
    'D:\\code\\project\\webapp\\node_modules\\next\\dist\\server\\lib\\start-server.js',
    'D:\\code\\project\\webapp\\node_modules\\next\\dist\\cli\\next-dev.js',
    'D:\\code\\project\\webapp\\node_modules\\next\\dist\\bin\\next'
  ]
}

[asimhafeezz]

i again installed all npm packages with my older package.json file but still getting this error. !!!

[polo13999]

the same here

Failed to compile.
./pages/_app.js
ReferenceError: Unknown helper createSuper

Build error occurred
Error: > Build failed because of webpack errors
at Object.build [as default] (/usr/src/app/node_modules/next/dist/build/index.js:192:15)
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! [email protected] build: next build
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the [email protected] build script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.
npm ERR! A complete log of this run can be found in:
npm ERR! /root/.npm/_logs/2020-03-21T07_52_27_717Z-debug.log
The command '/bin/sh -c npm run build' returned a non-zero code: 1

[asimhafeezz]

yes... and there is nothing like this i got on google yet :/
and my whole project is just messed up becuz of it.

[loopmode]

This seems to be an issue with [email protected] which was released some 20 hours ago.

In my project, pinning babel-loader to the previous version 8.0.6 helped.

[asimhafeezz]

how can i change the babel-loader version...sorry i have no idea about working with babel-loader.

[loopmode]

See https://stackoverflow.com/a/60787157/368254

[asimhafeezz]

thanku @loopmode it worked <3.

[tk-o]

Thank's @loopmode for sharing this one — it saved me a lot of trouble!

[nicolo-ribaudo]

EDIT: Fixed in @babel/[email protected]

---

This is caused by an incompatibility between @babel/core@<7.9.0 and @babel/[email protected].

We will fix it soon, but you can already make the error disappear by updating @babel/core:

npm --depth 999 update @babel/core

[asimhafeezz]

thank you its done <3 .

[QuentinRens]

Yep, impossible to build our (Vaadin-flow) project anymore :(

Usually, it goes like this : the plugin vaadin-maven-plugin run npm install without any issue.

But now, I'm getting that unknowHelper createSuper stuff, not sure how to fix it... Any help greatly welcome

[nicolo-ribaudo]

It should be fixed in in @babel/[email protected]