import() does not work

[philipahlberg]

I'm submitting a bug report

Webpack version:
4.1.1

Webpack Karma version:
2.0.13

Karma version:
2.0.0

Please tell us about your environment:
Windows 10

Browser: [Chrome 64] (probably others as well)

Current behavior:
import() fails with the error:
Error: Loading chunk 0 failed.

Expected/desired behavior:
import() should import a script and the exports should be available.

• If the current behavior is a bug, please provide the steps to reproduce and if possible a minimal demo of the problem along with a gist/jsbin of your webpack configuration.
  See https://github.com/philipahlberg/karma-webpack-dynamic-import for a setup that showcases the problem.
  The minimum necessary steps to reproduce is:

npm install --save-dev karma webpack karma-webpack

2. setup a test that uses import()
3. execute the test

• What is the expected behavior?
  import('./import.js') should import the file './import.js' and return its exports.

• What is the motivation / use case for changing the behavior?
  To allow testing things with dynamic imports.

[jamesopti]

Im seeing this issue as well but when using Webpack4's optimization.splitChunks to split out my vendor bundle.

Webpack version:
4.1.1

Webpack Karma version:
3.0.0

Karma version:
1.7.0

Please tell us about your environment:
Mac OSX Sierra 10.12.6

Browser: [Chrome 57]

Current behavior:
Vendor chunk fails to load

Expected/desired behavior:
vendor chunk should be available at http://localhost:9876/_karma_webpack_/vendor.js

Webpack Config:

optimization: {
  splitChunks: {
      cacheGroups: {
        vendor: {
          test: /\/node_modules\//,
          name: 'vendor',
          chunks: 'initial',
          filename: '[name].js',
        },
      },
    },
}

Custom Context File

...
  <script src="context.js"></script>
  <script src="debug.js"></script>
  <script type="text/javascript">
    // Configure our Karma
    %CLIENT_CONFIG%
    // All served files with the latest timestamps
    %MAPPINGS%
  </script>
  <!-- Dynamically replaced with <script> tags -->
  <script type="text/javascript" src="_karma_webpack_/vendor.js" crossorigin="anonymous"></script>
  <script type="text/javascript" src="_karma_webpack_/firstparty.js" crossorigin="anonymous"></script>
  %SCRIPTS%
  <script type="text/javascript">
    console.log('Using custom debug file test.customDebugFile.html');
    window.__karma__.loaded();
  </script>
...

[philipahlberg]

FWIW, it's also broken for karma-webpack 4.0.0-beta.0 + webpack 4.1.1.

[jamesopti]

+1 - This seems to be a regression that's happened multiple times now in a world where code splitting and dynamic imports are only getting more prevalent.

[ggriffithsIDBS]

+1 seeing this in latest version with Webpack 3
Error: Loading chunk 0 failed

[tingc10]

Not sure if this is the same error, but I solved this by setting webpack's output.chunkFilename and output.filename to [name].js. I noticed the chunk was being named to 1-undefined.js.

[matthieu-foucault]

The dynamic import bug on Windows (also reported in #362 ) was fixed in #373. installing karma-webpack@next would fix it