I tried the following code but it did not detect undefined variables. Any suggestions?
Next v15.3.2
eslint v9

import { dirname } from "path";
import { fileURLToPath } from "url";
import { FlatCompat } from "@eslint/eslintrc";
import js from "@eslint/js";

const __filename = fileURLToPath(import.meta.url);
const __dirname = dirname(__filename);

const compat = new FlatCompat({
  baseDirectory: __dirname,
  recommendedConfig: js.configs.recommended
});

const eslintConfig = [
  ...compat.config({
    extends: [
      "next",
      "next/core-web-vitals",
      "eslint:recommended",
      "plugin:react/recommended"
    ],
    rules: {
      "no-undef": "error",
      "no-use-before-define": "error"
    },
  })
];

export default eslintConfig;