Angular : An unhandled exception occurred: Cannot find module 'webpack/lib/ParserHelpers'

First of all, make sure that NPM is up-to-date.

npm i -g npm

Check version of Webpack. The version 5 (and after) is not currently supported by @angular-devkit/[email protected] (source).

Clean all :

remove node_modules folder and package-lock.json file

rm package-lock.json && rm -R node_modules

remove dist folder

Clear npm cache :

npm cache clean --force

To see which version are installed :

npm ls webpack

How to resolve ?

npm uninstall webpack
npm install --save-dev [email protected]

In my case it has been solved

1. npm audit fix / sudo npm audit fix (ubuntu)

2. Adding the following code in tsconfig.json "angularCompilerOptions": { "enableIvy": false }

you can use npm ci

description

I had the same error while working with npm workspaces. You can add to your package.json:

• Without using the npm workspace (and therefore having the issue), i guess the following should work:

"overrides": {
  "@angular-devkit/[email protected]": {
    "worker-plugin": {
      "webpack": "^4.39.2"
     }
  }
}

• However, i fixed it with:

"devDependencies": {
  // You other dev dependencies here
  "webpack": "^4.39.2"
},
"overrides": {
  "@angular-devkit/[email protected]": {
    "worker-plugin": {
      "webpack": "^4.39.2"
     }
  }
}