How to resolve fs.existsSync is not a function

I was facing the same Error like TypeError: fs.existsSync is not a function

So, I figured out that one extra line was added automatically which was creating this issue in import.

after removing this line from import

import { TRUE } from "node-sass";

the issue has been resolved.

I had the same error that you have. Your vscode might have added a new module to your js file. Remove that module and your app should work just fine.

You can allow webpack to use the Node's require and include fs etc. by targeting node in the config:

module.exports = {
  entry: './src/main.js',
  target: 'node',
  output: {
    path: path.join(__dirname, 'build'),
    filename: 'backend.js'
  }
}

As described here: https://webpack.js.org/concepts/targets/ and https://webpack.js.org/configuration/target/

I was working on an electron application, I wanted to send a message from node and get in on the react side, but I was having that same issue when requiring ipcRenderer from electron, I tried import { ipcRenderer } from 'electron'; and const { ipceRenderer } = require('electron') This leads to an error due to webpack transforming node's require to its own webpack_require. See more info here

What worked for me was to use

const {ipcRenderer} = window.require('electron'); on the react side/renderer side from electron

In my case, I forgot that I'd only imported the promises API, const fs = require("fs").promises, which doesn't have exist or existsSync functions in Node 17.4.0.

To use exist or existsSync, make sure you've imported fs using the sync API (const fs = require("fs")).

_{Note: I'm adding this answer as a possible solution for future visitors to a canonical thread for the error, not OP who appears to have required fs correctly.}

It is nothing to worry about, check your code for something like import { types } from "node-sass";, it would have mistakenly and automatically imported without you know. Remove that line, and everything should work perfectly.

Even if it is not type, it is something from node-sass in your node_modules file, and you can't edit that file. So look for and remove import { types } from "node-sass"

In my case VSCode added a arbitrary import from electron. After removing it my application worked.

import { Menu } from 'electron';