[BREAKING CHANGE] SyntaxError importing RawSource from webpack-sources

[erropix]

• Manifest Plugin Version: 6.0.0
• Webpack Version: 5.102.1
• Operating System: Windows 11
• Node Version: 22.21.0
• Link to reproduction: https://github.com/erropix/webpack-manifiest-plugin-issue-313

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Expected Behavior

The plugin should work as in v5.x without syntax errors when used in a CommonJS Webpack configuration.

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Actual Behavior

After upgrading from v5.0.1 → v6.0.0, the build fails with the following error:

[webpack-cli] SyntaxError: The requested module 'webpack-sources' does not provide an export named 'RawSource'
at ModuleJobSync.runSync (node:internal/modules/esm/module_job:440:37)
at ModuleLoader.importSyncForRequire (node:internal/modules/esm/loader:435:47)
at loadESMFromCJS (node:internal/modules/cjs/loader:1537:24)
at Module._compile (node:internal/modules/cjs/loader:1688:5)

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Additional Information

• v5 used webpack-sources@2.3.1
• v6 upgraded to webpack-sources@3.3.3
• The export format has been changed in webpack-sources@3.3.0

[shellscape]

Yes, major versions have breaking changes. All of our tests pass, so please feel free to open a PR with what you feel the fix is along with a test to prevent regression.

[erropix]

I understand that major versions can introduce breaking changes, but the repo I gave you is using the minimal setup code and still fails, so that means your tests are not covering the basic webpack example.

Can you please check the repo?

[erropix]

I also tried runing webpack with the cli, and the error is still the same

import { RawSource } from 'webpack-sources';
         ^^^^^^^^^
SyntaxError: Named export 'RawSource' not found. The requested module 'webpack-sources' is a CommonJS module, which may not support all module.exports as named exports.
CommonJS modules can always be imported via the default export, for example using:

import pkg from 'webpack-sources';
const { RawSource } = pkg;

This suggests that the webpack-source module is a CommonJS package, which means it does not offer named exports.

[shellscape]

see my previous comment

[erropix]

see my previous comment

That means no fix?

[shellscape]

[facepalm.gif]

please feel free to open a PR with what you feel the fix is along with a test to prevent regression.

This is my last interaction with this issue.

[erropix]

I am not familiar with your codebase to open a PR or fix it.

Anyway, I just spotted this issue and reported it. I rolled back to v5 for my project.

[dcsaszar]

Here's how a test that prevents regression could look like (needs build first though):

import { execSync } from 'node:child_process';
import test from '../helpers/ava-compat';

test('can be used as documented', (t) => {
  const readmeCode = "import { WebpackManifestPlugin } from 'webpack-manifest-plugin'";

  t.deepEqual(execSync(`node -e "${readmeCode}"`, { encoding: 'utf-8' }), '');
});