Bug: TypeScript types correct? DOM required as lib?

[sdavids]

Environment

ESLint version: 9.26.0
@eslint/css version: 0.7.0
Node version: 22.15.0
npm version: 10.9.2
Operating System: macOS

Which language are you using?

stylesheet

What did you do?

$ mkdir -p /tmp/test && cd "$_"
$ npm init -y
$ npm i -D typescript eslint @eslint/css typescript-eslint
$ cat <<'EOF' >eslint.config.mts
import css from '@eslint/css';
import tseslint from 'typescript-eslint';
import type { FlatConfig } from '@typescript-eslint/utils/ts-eslint';

const cfg: FlatConfig.ConfigArray = tseslint.config({
  files: ['*.css'],
  plugins: {css},
  language: 'css/css',
  rules: {...css.configs.recommended.rules}
 });

export default cfg;
EOF
$ echo '{"compilerOptions":{"lib":["es2024"],"skipLibCheck":true,"noEmit":true,"module":"es2022","moduleResolution":"bundler"}}' >tsconfig.json
$ echo 'p{}' >test.css

Check that the ESLint setup works:

$ NODE_OPTIONS="--experimental-strip-types --disable-warning=ExperimentalWarning" npx eslint --flag unstable_native_nodejs_ts_config .

/private/tmp/test/test.css
  1:2  error  Unexpected empty block found  css/no-empty-blocks

✖ 1 problem (1 error, 0 warnings)

The error is OK—the config works.

$ npx tsc
node_modules/@eslint/css/dist/esm/types.ts:34:47 - error TS2304: Cannot find name 'Comment'.

34 export type CSSSyntaxElement = CssNodePlain | Comment;
                                                 ~~~~~~~


Found 1 error in node_modules/@eslint/css/dist/esm/types.ts:34

This error is unexpected and gives no indication on how to fix it.

What did you expect to happen?

No error or if this is the desired behavior then the docs should be updated to mention the dom requirement.

What actually happened?

Type error.

Link to Minimal Reproducible Example

minimal reproduction is above

Participation

• I am willing to submit a pull request for this issue.

Additional comments

Adding dom to lib will fix the error:

$ echo '{"compilerOptions":{"lib":["es2024","dom"],"skipLibCheck":true,"noEmit":true,"module":"es2022","moduleResolution":"bundler"}}' >tsconfig.json
$ npx tsc

https://www.typescriptlang.org/tsconfig/#lib

---

I am unsure if it is OK if the DOM types leak, requiring them might lead to other issues.

[fasttime]

I think this has been fixed in #119.

[sdavids]

Seems like it, but I will leave this open and check the next release…

[jimmy-zhening-luo]

When is the next release? I wish fix #119 could have been cut into a patch release, since 0.7.0 is an unusable major version (per semver) for anybody using TypeScript, and has been since April 16, 2025 (almost a month).

[nzakas]

v0.8.0 has been released: https://github.com/eslint/css/releases/tag/css-v0.8.0

[sdavids]

Verified with v0.8.0.