Webpack-remove-empty-scripts NPM

The problem this plugin solves

Webpack generates a JS file for each resource defined in the entry option.

For example, you have a style file in the entry option:

module.exports = {
  entry: {
    styles: './styles.scss',
  },
}

The following files are generated in the output directory:

dist/styles.css
dist/styles.js // <= unexpected empty JS file

This plugin removes generated empty JS files.

Warning
This plugin is the Emergency Crutch 🩼 for the mini-css-extract-plugin issue.\ The mini-css-extract-plugin extract CSS, but not eliminate a generated empty JS file.
Note
This plugin is compatible with Webpack 5. For Webpack 4 use webpack-fix-style-only-entries.

Install

npm install webpack-remove-empty-scripts --save-dev

Usage with mini-css-extract-plugin

The example of webpack.config.js:

const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const RemoveEmptyScriptsPlugin = require('webpack-remove-empty-scripts');

module.exports = {
  entry: {
    'main' : './app/main.js',
    'styles': ['./common/styles.css', './app/styles.css']
  },
  module: {
    rules: [
      {
        test: /\.css$/,
        use: [
          MiniCssExtractPlugin.loader,
          'css-loader',
        ]
      },
    ]
  },
  plugins: [
    // removes the empty `.js` files generated by webpack
    new RemoveEmptyScriptsPlugin(),
    new MiniCssExtractPlugin({
      filename: '[name].[chunkhash:8].css',
    }),
  ],
};

See the plugin options.

Usage with html-webpack-plugin

✅ It is recommended to use the new powerful html-bundler-webpack-plugin instead of:
html-webpack-plugin
mini-css-extract-plugin
webpack-remove-empty-scripts

Highlights of html-bundler-webpack-plugin

Prevents generating unexpected empty JS files.
An entry point can be an HTML template.
Source scripts and styles can be specified directly in HTML using <script> and <link>.
Extracts JS and CSS from their sources specified in HTML.
Resolving source assets specified in standard attributes href src srcset etc.
Inline JS, CSS, SVG, PNG without additional plugins and loaders.
Support for template engines such as Eta, EJS, Handlebars, Nunjucks, LiquidJS and others.

Simple usage example

Add source scripts and styles directly to HTML:

<html>
<head>
  <!-- specify source styles -->
  <link href="./style.scss" rel="stylesheet">
  <!-- specify source scripts here and/or in body -->
  <script src="./main.js" defer="defer"></script>
</head>
<body>
  <h1>Hello World!</h1>
  <!-- specify source images -->
  <img src="./logo.png">
</body>
</html>

The generated HTML contains the output filenames of the processed assets:

<html>
<head>
  <link href="assets/css/style.05e4dd86.css" rel="stylesheet">
  <script src="assets/js/main.f4b855d8.js" defer="defer"></script>
</head>
<body>
  <h1>Hello World!</h1>
  <img src="assets/img/logo.58b43bd8.png">
</body>
</html>

Add the HTML templates in the entry option:

const HtmlBundlerPlugin = require('html-bundler-webpack-plugin');

module.exports = {
  plugins: [
    new HtmlBundlerPlugin({
      // define a relative or absolute path to template pages
      entry: 'src/views/',
      // OR define templates manually
      entry: {
        index: 'src/views/home.html', // => dist/index.html
        'news/sport': 'src/views/news/sport/index.html', // => dist/news/sport.html
      },
    }),
  ],
  // ... loaders for styles, images, etc.
};

Options

`enabled`

Type: boolean Default: true Enable / disable the plugin. Tip: Use disable for development to improve performance.

`stage`

Type: number Values:

RemoveEmptyScriptsPlugin.STAGE_BEFORE_PROCESS_PLUGINS (default)\ Remove empty scripts before processing other plugins.\ For example, exact this stage needs for properly work of the webpack-manifest-plugin.
RemoveEmptyScriptsPlugin.STAGE_AFTER_PROCESS_PLUGINS\ Remove empty scripts after processing all other plugins.\ For example, exact this stage needs for properly work of the @wordpress/dependency-extraction-webpack-plugin.

Webpack plugins use different stages for their functionality. For properly work other plugins can be specified the stage when should be removed empty scripts: before or after processing of other Webpack plugins.

See usage example.

Warning
Because webpack-manifest-plugin and @wordpress/dependency-extraction-webpack-plugin needs different stages both plugins can't be used together with RemoveEmptyScriptsPlugin at one configuration.

`extensions`

Type: RegExp Default: /\.(css|scss|sass|less|styl)([?].*)?$/ Note: the Regexp should have the query part at end ([?].*)?$ to match assets like style.css?key=val Type: string[] Default: ['css', 'scss', 'sass', 'less', 'styl']. It is automatically converted to type RegExp. \ Search for empty js files in source files only with these extensions.

`ignore`

Type: string | RegExp | string[] | RegExp[] Default: null Ignore source files.

`remove`

Type: RegExp Default: /\.(js|mjs)$/ Remove generated scripts.

`verbose`

Type: boolean Default: false Show process information.

Recipes

Show logs to console by development

const isProduction = process.env.NODE_ENV === 'production';
new RemoveEmptyScriptsPlugin({ verbose: isProduction !== true })

Disable plugin by development to improve performance

const isProduction = process.env.NODE_ENV === 'production';
new RemoveEmptyScriptsPlugin({ enabled: isProduction === true })

Specify stage for properly work some plugins

For example, using @wordpress/dependency-extraction-webpack-plugin the empty scripts must be removed after processing all plugins.

const path = require('path');
const DependencyExtractionWebpackPlugin = require('@wordpress/dependency-extraction-webpack-plugin');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const RemoveEmptyScriptsPlugin = require('webpack-remove-empty-scripts');

module.exports = {
  output: {
    path: path.join(__dirname, 'public'),
  },
  entry: {
    'main': './src/sass/main.scss',
  },
  module: {
    rules: [
      {
        test: /\.scss$/,
        use: [MiniCssExtractPlugin.loader, 'css-loader', 'sass-loader'],
      },
    ],
  },
  plugins: [
    new MiniCssExtractPlugin(),
    new DependencyExtractionWebpackPlugin(),
    new RemoveEmptyScriptsPlugin({
      stage: RemoveEmptyScriptsPlugin.STAGE_AFTER_PROCESS_PLUGINS, // <- use this option
    }),
  ],
};

Identify only `.foo` and `.bar` extensions as styles

new RemoveEmptyScriptsPlugin({ extensions: /\.(foo|bar)$/ })

Usage a javascript entry to styles

Give an especial extension to your file, for example .css.js:

new RemoveEmptyScriptsPlugin({ extensions: /\.(css.js)$/ })

Remove generated scripts `.js` `.mjs` except `.rem.js` `.rem.mjs`

new RemoveEmptyScriptsPlugin({ remove: /(?<!\.rem)\.(js|mjs)$/ })

Recursive ignore all js files from directory, for example `my-workers/`

new RemoveEmptyScriptsPlugin({
  ignore: [
    /my-workers\/.+\.js$/,
  ]
})

Usage webpack-hot-middleware

new RemoveEmptyScriptsPlugin({
  ignore: [
    'webpack-hot-middleware',
  ]
})

See the test case.

Testing

npm run test will run the unit and integration tests.\ npm run test:coverage will run the tests with coverage.

Who use this plugin

Also See

ansis - The Node.js library for ANSI color styling of text in terminal.
html-bundler-webpack-plugin - HTML bundler plugin for webpack handels a template as an entry point, extracts CSS and JS from their sources specified in HTML, supports template engines like Eta, EJS, Handlebars, Nunjucks and others "out of the box".
pug-plugin - plugin for Webpack compiles Pug files to HTML, extracts CSS and JS from their sources specified in Pug.
pug-loader - loader for Webpack renders Pug to HTML or template function. Optimized for using with Vue.