disallow-stylelint-null-rule-config

Disallow null values in top-level Stylelint rules entries.

Targeted pattern scope

This rule targets Stylelint config modules such as stylelint.config.ts, stylelint.config.mjs, and .stylelintrc.js.

It focuses on top-level exported config objects, including configs wrapped in defineConfig(...).

What this rule reports

Reports top-level rule entries configured as null, for example "at-rule-no-unknown": null.

Why this rule exists

null entries hide rule intent in shared configs and can mask policy drift. Explicit rule values are easier to audit and maintain.

❌ Incorrect

export default {
    rules: {
        "at-rule-no-unknown": null,
    },
};

✅ Correct

export default {
    rules: {
        "at-rule-no-unknown": true,
    },
};

Behavior and migration notes

This rule reports null rule entries and does not auto-fix because desired replacement values are policy-specific.

ESLint flat config example

import stylelint2 from "eslint-plugin-stylelint-2";

export default [stylelint2.configs.configuration];

When not to use it

Do not use this rule if your team intentionally uses null to disable inherited rules in shared config files.

Package documentation

Stylelint package documentation:

Rule catalog ID: R030

Further reading

• Stylelint rules