Upgraded eslint dependencies and config file.

eslint.config.mjs

@@ -0,0 +1,100 @@
+import typescriptEslint from "@typescript-eslint/eslint-plugin";
+import globals from "globals";
+import tsParser from "@typescript-eslint/parser";
+import path from "node:path";
+import { fileURLToPath } from "node:url";
+import js from "@eslint/js";
+import { FlatCompat } from "@eslint/eslintrc";
+
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = path.dirname(__filename);
+const compat = new FlatCompat({
+  baseDirectory: __dirname,
+  recommendedConfig: js.configs.recommended,
+  allConfig: js.configs.all,
+});
+
+export default [
+  {
+    ignores: [
+      "**/dist/**/*",
+      "**/node_modules",
+      "packages/turf/turf.js",
+      "packages/turf/turf.min.js",
+      "packages/turf/test.example.js",
+    ],
+  },
+  ...compat.extends(
+    "eslint:recommended",
+    "plugin:@typescript-eslint/recommended",
+    "plugin:prettier/recommended"
+  ),
+  {
+    plugins: {
+      "@typescript-eslint": typescriptEslint,
+    },
+
+    languageOptions: {
+      globals: {
+        ...globals.node,
+      },
+
+      parser: tsParser,
+      ecmaVersion: 6,
+      sourceType: "module",
+    },
+
+    rules: {
+      "@typescript-eslint/no-unused-vars": [
+        "error",
+        {
+          argsIgnorePattern: "^_",
+        },
+      ],
+
+      "@typescript-eslint/explicit-module-boundary-types": "off",
+      "@typescript-eslint/no-explicit-any": "off",
+      "@typescript-eslint/no-non-null-assertion": "off",
+      "@typescript-eslint/no-var-requires": "off",
+      "no-constant-condition": "off",
+      "no-redeclare": "off",
+      "no-var": "off",
+      "prefer-const": "off",
+    },
+  },
+  {
+    files: ["packages/*/types.ts", "packages/*/test.ts"],
+
+    rules: {
+      "@typescript-eslint/no-unused-vars": "off",
+      "@typescript-eslint/no-unused-expressions": "off",
+    },
+  },
+  {
+    files: [
+      "**/.eslintrc.js",
+      "packages/*/bench.js",
+      "packages/*/test.js",
+      "packages/turf/rollup.config.js",
+      "scripts/check-dependencies.js",
+    ],
+
+    languageOptions: {
+      globals: {
+        ...globals.node,
+      },
+    },
+  },
+  {
+    files: [
+      "packages/turf-isobands/lib/marchingsquares-isobands.js",
+      "packages/turf-isolines/lib/marchingsquares-isocontours.js",
+    ],
+
+    languageOptions: {
+      globals: {
+        ...globals.browser,
+      },
+    },
+  },
+];

package.json

@@ -29,26 +29,29 @@
   },
   "packageManager": "[email protected]+sha512.d1a029e1a447ad90bc96cd58b0fad486d2993d531856396f7babf2d83eb1823bb83c5a3d0fc18f675b2d10321d49eb161fece36fe8134aa5823ecd215feed392",
   "devDependencies": {
+    "@eslint/eslintrc": "^3.2.0",
+    "@eslint/js": "^9.16.0",
     "@monorepolint/cli": "0.5.0",
     "@monorepolint/config": "0.5.0",
     "@monorepolint/core": "0.5.0",
     "@monorepolint/rules": "0.5.0",
     "@types/node": "18.11.9",
-    "@typescript-eslint/eslint-plugin": "^6.10.0",
-    "@typescript-eslint/parser": "^6.10.0",
+    "@typescript-eslint/eslint-plugin": "^8.17.0",
+    "@typescript-eslint/parser": "^8.17.0",
     "acorn": "^7.4.1",
     "camelcase": "^8.0.0",
     "d3-queue": "*",
     "decamelize": "^6.0.0",
     "dependency-tree": "^11.0.0",
     "documentation": "^14.0.3",
     "es-check": "^7.1.1",
-    "eslint": "^8.53.0",
-    "eslint-config-prettier": "^9.0.0",
-    "eslint-plugin-prettier": "^5.0.1",
+    "eslint": "^9.16.0",
+    "eslint-config-prettier": "^9.1.0",
+    "eslint-plugin-prettier": "^5.2.1",
     "esm": "^3.2.25",
     "fs-extra": "^11.1.1",
     "glob": "^10.3.10",
+    "globals": "^15.13.0",
     "husky": "^9.0.0",
     "lerna": "^8.1.9",
     "lint-staged": "^15.2.8",