Entrypoint undefined = extract-text-webpack-plugin-output-filename after upgrade to webpack 4

[ngohungphuc]

I got this error

My webpack.config file

const path = require("path");
const webpack = require("webpack");
const ExtractTextPlugin = require("extract-text-webpack-plugin");
const UglifyJSPlugin = require("uglifyjs-webpack-plugin");

module.exports = {
  entry: {
    main: "./wwwroot/frontend/js/main.js"
  },
  output: {
    path: path.resolve(__dirname, "wwwroot/dist"),
    filename: "[name].js",
    publicPath: "/dist/"
  },
  plugins: [
    new ExtractTextPlugin({
      filename: "cmscore.css"
    }),
    new UglifyJSPlugin({
      sourceMap: true
    })
  ],
  module: {
    rules: [
      {
        test: /\.scss$/,
        use: ExtractTextPlugin.extract({
          fallback: "style-loader",
          use: "css-loader!sass-loader"
        })
      },
      {
        test: /\.(js|jsx)$/,
        exclude: /node_modules/,
        use: ["babel-loader", "eslint-loader"]
      }
    ]
  },
  watch: true
};

Am I missing something or webpack 4 is not ready to use with this plugin ?

[RussGlover]

I have this same issue, it only occurs when webpack mode is set to production.

[AtofStryker]

Webpack 4's new tapable plugin library broke some of the existing plugins. The fix should be relatively simple

[ngohungphuc]

I get this error in dev mode not sure about prod mode may be the same lol @RussGlover

[jbasilio]

I have the same issue in Webpack 4. Regardless of mode.

[alexander-akait]

Somebody can create minimum reproducible test repo?

[mauriciofergo]

Same error here,
The build is performed properly but when I enter the local server the entry point is not loaded.
In my case I'm using babel-polyfill (not sure if it's the correct way)

main: ['babel-polyfill', './js/main.js'],

[DaveBitter]

Same issue here. The fix probably isn't that big of a task. If I had more knowledge on this I would make a PR. Is there any ETA for the fix. I now have to downgrade to Webpack 3 just for this plugin.

[leereichardt]

Is Webpack 4 even ready for production use? I feel like they need to delay a few more weeks to allow some of the most important plugins to be updated?

[Edward-Lombe]

@leereichardt After using it for a couple of days, my survey would be no. It still works, but for a program as reliant on plugins as webpack is (especially those under the quasi-official webpack contrib), I would expect the release of v4 to correspond to all the important plugins being updated to v4.

[ngohungphuc]

@leereichardt

Webpack 4's new tapable plugin library broke some of the existing plugins. The fix should be relatively simple

[leereichardt]

So it has been said on various issues for the past 50 odd days. Yet this relatively simple fix hasn’t been fixed?

[ngohungphuc]

not sure why is take so long