Source Maps not working with Webpack

Question

I\'m pretty new to webpack and having some trouble configuring it to produce the necessary source maps. In the devtools it says

Source Map detected

Answer 1

Make sure you have --mode development in your npm build script,

{
 "name": "test",
 "version": "1.0.1",
 "description": "",
 "scripts": {
 "build": "webpack",
  "start": "webpack-dev-server --mode development --open"
   "test": "echo \"Error: no test specified\" && exit 1",
 },
  "author": "",
  "license": "",
  "devDependencies": {
  "babel-core": "^6.26.3",
  "babel-loader": "^7.1.5",
  "babel-preset-env": "^1.7.0",
  "webpack": "^4.19.1",
  "webpack-cli": "^3.1.0",
  "webpack-dev-server": "^3.1.8"
  },
  "dependencies": {}
 }

webpack.config.js

const path = require('path');
var webpack = require('webpack');

module.exports = {
    entry: './src/web.js',
    devtool: 'inline-source-map',
    output: {
        filename: 'main.js',
        path: path.resolve(__dirname, 'dist')
    },
    mode: 'development',
    module: {
        rules: [{
            test: /\.js$/,
            exclude: /(node_modules)/,
            use: {
                loader: "babel-loader",
                options: {
                    presets: ["babel-preset-env"]
                }
            }
        }]
    },
    devServer: {
        inline: true,
        contentBase: path.join(__dirname, 'dist'),
        compress: true,
        port: 9000,
        watchOptions: {
            index: 'index.html',
            open: true,
            poll: true,
            watchContentBase: true
        }
    },
    watch: true,
    watchOptions: {
        aggregateTimeout: 500,
        ignored: /node_modules/,
        poll: 3000
    }
}