Webpack issues with MGT version 4

[Ofer-Gal]

I assume you mean \node_modules\spfx-fast-serve-helpers\lib\templates\webpack.extend.js

/*
* User webpack settings file. You can add your own settings here.
* Changes from this file will be merged into the base webpack configuration file.
* This file will not be overwritten by the subsequent spfx-fast-serve calls.
*/

/**
 * you can add your project related webpack configuration here, it will be merged using webpack-merge module
 * i.e. plugins: [new webpack.Plugin()]
 */
const webpackConfig = {

}

/**
 * For even more fine-grained control, you can apply custom webpack settings using below function
 * @param {object} initialWebpackConfig - initial webpack config object
 * @param {object} webpack - webpack object, used by SPFx pipeline
 * @returns webpack config object
 */
const transformConfig = function (initialWebpackConfig, webpack) {
  // transform the initial webpack config here, i.e.
  // initialWebpackConfig.plugins.push(new webpack.Plugin()); etc.

  return initialWebpackConfig;
}

module.exports = {
  webpackConfig,
  transformConfig
}

thank you

[Ofer-Gal]

I am guilty of not reading "Webpack extensibility" but even trying to use the example in samples/advanced/fast-serve/webpack.extend.js it did not work.

I don't understand webpack that much.

[s-KaiNet]

Just try to put below code in your webpack.extend.js:

/*
* User webpack settings file. You can add your own settings here.
* Changes from this file will be merged into the base webpack configuration file.
* This file will not be overwritten by the subsequent spfx-fast-serve calls.
*/

// you can add your project related webpack configuration here, it will be merged using webpack-merge module
// i.e. plugins: [new webpack.Plugin()]
const webpackConfig = {
  module: {
    rules: [{
      test: /\.js$/,
      include: [
        /lit/,
        /@lit/,
        /lit-html/
      ],
      use: {
        loader: 'babel-loader',
        options: {
          plugins: [
            '@babel/plugin-transform-optional-chaining',
            '@babel/plugin-transform-nullish-coalescing-operator',
            '@babel/plugin-transform-logical-assignment-operators'
          ]
        }
      }
    }]
  }
}

// for even more fine-grained control, you can apply custom webpack settings using below function
const transformConfig = function (initialWebpackConfig, webpack) {
  // transform the initial webpack config here, i.e.
  // initialWebpackConfig.plugins.push(new webpack.Plugin()); etc.

  return initialWebpackConfig;
}

module.exports = {
  webpackConfig,
  transformConfig
}

[Ofer-Gal]

That worked fine.
Thanks!