Bug: provided syntax object is not JSON-serializable, which causes ESLint to crash in certain situations

[andreww2012]

tailwind4 or tailwind3 syntaxes from this package appear not to be JSON-serializable.

In cases when ESLint tries to serialize the config (for example, when --cache or --print-config option is used), it crashes with the following error:

The requested operation requires ESLint to serialize configuration data,
but the configuration key "Value.theme" contains a function value,
which cannot be serialized.

Please double-check your configuration for errors.

Reproduction: https://stackblitz.com/edit/vitejs-vite-7lu9csyw

Run npx eslint --cache or npx eslint --print-config style.css.

[nzakas]

Thanks for the report. This is actually an issue with the CSS plugin, which should be providing serialization for the config. I'll leave this open to track.

[ShayanTheNerd]

I run into the same issue, but for a different reason:

The requested operation requires ESLint to serialize configuration data,
but the configuration key "parse.prelude" contains a function value,
which cannot be serialized.

Please double-check your configuration for errors.

[nzakas]

You can follow this PR for updates: eslint/css#212