webpack.dev.js

const path = require('path');

const { merge } = require('webpack-merge');
const webpack = require('webpack');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');

const common = require('./webpack.common.js');

module.exports = merge(common, {
  mode: 'development',
  devServer: {
    contentBase: path.join(__dirname, 'dist'),
    port: 9000,
    hot: true,
  },
  devtool: 'inline-source-map',
  module: {
    rules: [
      {
        test: /\.less$/,
        use: [
          'css-hot-loader',
          MiniCssExtractPlugin.loader,
          'css-loader',
          'less-loader',
        ],
        exclude: /node_modules/,
      },
    ],
  },
  plugins: [
    new webpack.HotModuleReplacementPlugin(),
    new MiniCssExtractPlugin({ filename: '[name].css' }),
  ],
  output: {
    filename: '[name].js',
  },
});