Terser plugin Minimizer doesn't return result

[normancarcamo]

Bug report

What is the current behavior?

Error when compiling for production using terser options

ERROR in ./javascripts/webpack/main.js from Terser plugin
Minimizer doesn't return result

{
  optimization: {
    minimize: true,
    minimizer: [
      new TerserPlugin({
        minify: TerserPlugin.uglifyJsMinify,
        extractComments: false,
        terserOptions: {
          keep_classnames: true,
          keep_fnames: true,
        },
      }),
    ],
  },
}

If the current behavior is a bug, please provide the steps to reproduce.

What is the expected behavior?

It should compile for production without errors.

Other relevant information:

➜ ./node_modules/.bin/webpack --version

System:
OS: macOS 11.4
CPU: (8) x64 Intel(R) Core(TM) i7-4770HQ CPU @ 2.20GHz
Memory: 1.78 GB / 16.00 GB
Binaries:
Node: 18.18.2 - ~/.nvm/versions/node/v18.18.2/bin/node
Yarn: 1.22.21 - ~/.nvm/versions/node/v18.18.2/bin/yarn
npm: 9.8.1 - ~/.nvm/versions/node/v18.18.2/bin/npm
Browsers:
Brave Browser: 103.1.41.96
Chrome: 119.0.6045.159
Safari: 14.1.1
Packages:
babel-loader: ^9.1.3 => 9.1.3
clean-webpack-plugin: ^4.0.0 => 4.0.0
css-loader: ^6.8.1 => 6.8.1
eslint-loader: ^1.7.1 => 1.9.0
eslint-webpack-plugin: ^4.0.1 => 4.0.1
sass-loader: ^13.3.2 => 13.3.2
style-loader: ^3.3.3 => 3.3.3
terser-webpack-plugin: ^5.3.9 => 5.3.9
uglifyjs-webpack-plugin: ^1.2.4 => 1.2.4
webpack: ^5.88.2 => 5.89.0
webpack-cli: ^5.1.4 => 5.1.4
webpack-dev-server: ^4.15.1 => 4.15.1
webpack-merge: ^5.10.0 => 5.10.0

[alexander-akait]

Please provide reproducible test repo, maybe you have broken JS syntax...

[varit05]

I faced this issue and came across this thread.

I've created a test repo where this is still producible.

I have tried the steps from the webpack documentation

Happy to help in any capacity.

[alexander-akait]

@varit05 I see, the problem is ``deadCode is not a supported option by uglify-js, WIP on fix to output better errors here

[alexander-akait]

@varit05 There is a fix - webpack/terser-webpack-plugin#641, release will be soon

[varit05]

@alexander-akait Thanks for the quick resolution, I really appreciate it.

[varit05]

I’m happy to confirm that the plugin now provides a clearer error with the terserOptions. I have updated the repo and played with the different terserOptions.

Thank you @alexander-akait for your prompt response.