Cannot read config file: eslint.config.mjs.

[kku39]

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Bug report

When I try webpack build, the following error occurs.

ERROR in [eslint] Cannot read config file: C:\dev\my-project\eslint.config.mjs
Error: end of the stream or a document separator is expected (32:62)

It looks like YAMLException, but my config file is mjs.

Some other people already reported the same problem on other projects as follows, but I think this is eslint-webpack-plugin's problem.

• https://github.com/webpack/webpack/discussions/18434
• https://github.com/eslint/eslint/issues/18514

Actual Behavior

ERROR in [eslint] Cannot read config file: C:\dev\my-project\eslint.config.mjs
Error: end of the stream or a document separator is expected (3:11)

 1 |
 2 | export default [{
 3 |   "no-var": 2
---------------^
 4 | }];

Expected Behavior

Lint works correctly, as same as executing npx eslint .

If you run my sample project, it is the expected behavior that eslint points out linting error of "no-var" at index.ts.

How Do We Reproduce?

1. Clone my sample project: https://github.com/kku39/issue-repro-of-eslint-webpack-plugin
2. npm ci
3. npx webpack

Please paste the results of npx webpack-cli info here, and mention other relevant information (Edited)

$ npx webpack-cli info

  System:
    OS: Windows 10 10.0.19045
    CPU: (8) x64 Intel(R) Core(TM) i7-9700K CPU @ 3.60GHz
    Memory: 18.83 GB / 31.92 GB
  Binaries:
    Node: 20.16.0 - C:\Program Files\nodejs\node.EXE
    Yarn: 1.22.19 - ~\AppData\Roaming\npm\yarn.CMD
    npm: 10.1.0 - C:\Program Files\nodejs\npm.CMD
  Browsers:
    Chrome: 127.0.6533.101
    Edge: Chromium (127.0.2651.74)
    Internet Explorer: 11.0.19041.4355
  Packages:
    eslint-webpack-plugin: ^4.2.0 => 4.2.0
    webpack: ^5.93.0 => 5.93.0
    webpack-cli: ^5.1.4 => 5.1.4