webpack.config.js

var Encore = require('@symfony/webpack-encore');

// Manually configure the runtime environment if not already configured yet by the "encore" command.
// It's useful when you use tools that rely on webpack.config.js file.
if (!Encore.isRuntimeEnvironmentConfigured()) {
  Encore.configureRuntimeEnvironment(process.env.NODE_ENV || 'dev');
}

Encore
  .setOutputPath('public/build/')
  .setPublicPath('/build')

  /*
   * ENTRY CONFIG
   *
   * Add 1 entry for each "page" of your app
   * (including one that's included on every page - e.g. "app")
   *
   * Each entry will result in one JavaScript file (e.g. app.js)
   * and one CSS file (e.g. app.css) if your JavaScript imports CSS.
   */
  .addEntry('app', './assets/js/app.js')
  //.addEntry('page1', './assets/js/page1.js')
  //.addEntry('page2', './assets/js/page2.js')

  // will require an extra script tag for runtime.js
  // but, you probably want this, unless you're building a single-page app
  .enableSingleRuntimeChunk()

  /*
   * FEATURE CONFIG
   *
   * Enable & configure other features below. For a full
   * list of features, see:
   * https://symfony.com/doc/current/frontend.html#adding-more-features
   */
  .cleanupOutputBeforeBuild()
  .enableBuildNotifications()
  .enableSourceMaps(!Encore.isProduction())

  // enables @babel/preset-env polyfills
  .configureBabel(() => {}, {
    useBuiltIns: 'usage',
    corejs: 3
  })

  .enableSassLoader()

  // uncomment if you use TypeScript
  //.enableTypeScriptLoader()

  // uncomment if you're having problems with a jQuery plugin
  //.autoProvidejQuery()
;

module.exports = Encore.getWebpackConfig();