React: "react-scripts start" cannot find module webpack

Question

I am getting this error when I am not even using webpack in this particular branch. I have never encountered this error in my main branch before. However, I wanted to learn webpack so I created a webpack branch of my project and install webpack in that branch(Assuming that I did correctly install webpack locally). Now when I switch back to my main, and tried to run "npm start". I am getting into this error.

> react-scripts start

module.js:550
    throw err;
    ^

Error: Cannot find module 'webpack'
    at Function.Module._resolveFilename (module.js:548:15)
    at Function.Module._load (module.js:475:25)
    at Module.require (module.js:597:17)
    at require (internal/module.js:11:18)
    at Object.<anonymous> (C:\Users\pzheng\my-app\node_modules\webpack-dev-server\lib\Server.js:22:17)
    at Module._compile (module.js:653:30)
    at Object.Module._extensions..js (module.js:664:10)
    at Module.load (module.js:566:32)
    at tryModuleLoad (module.js:506:12)
    at Function.Module._load (module.js:498:3)

When I tried to run "npm run build", this error appears instead:

Error: Cannot find module 'webpack/lib/Chunk'
    at Function.Module._resolveFilename (module.js:548:15)
    at Function.Module._load (module.js:475:25)
    at Module.require (module.js:597:17)
    at require (internal/module.js:11:18)
    at Object.<anonymous> (C:\Users\pzheng\my-app\node_modules\extract-text-webpack-plugin\dist\index.js:17:14)
    at Module._compile (module.js:653:30)
    at Object.Module._extensions..js (module.js:664:10)
    at Module.load (module.js:566:32)
    at tryModuleLoad (module.js:506:12)
    at Function.Module._load (module.js:498:3)
    at Module.require (module.js:597:17)
    at require (internal/module.js:11:18)
    at Object.<anonymous> (C:\Users\pzheng\my-app\node_modules\extract-text-webpack-plugin\dist\cjs.js:3:18)
    at Module._compile (module.js:653:30)
    at Object.Module._extensions..js (module.js:664:10)
    at Module.load (module.js:566:32)

Many SO posts suggesting downloading webpack, but I do not wish to use webpack for this branch, so many SO posts are not helpful.

What I have tried: I checked my package.json file, there is no webpack dependency in my main branch. However, I do see webpack in my package.lock.json file when I search for the word webpack

What I am using: I am using create-react-app library.

What I need help with: I am trying to figure out the cause of this error and how to fix it. Does it have to do with me installing webpack in the other branch?

Answer 1

I faced this when I was trying to use react-scripts in an existing react app that wasn't scaffolded using create-react-app. The problem was the package-lock file. Deleting node_modules and package-lock.json and running npm install did the trick for me.

Answer 2

Ok, this is weird but this is how I fixed it.

I think this error has to do with "react-script"

I was using [email protected], as soon as I upgrade my react script to 2.1.3, which is the latest version published 4 days ago, this error is fixed.