switch to flat config

eslint.config.cjs

@@ -0,0 +1,30 @@
+const globals = require("globals");
+const js = require("@eslint/js");
+const prettierConfig = require("eslint-config-prettier");
+const prettierPlugin = require("eslint-plugin-prettier");
+const mochaPlugin = require("eslint-plugin-mocha");
+
+module.exports = [
+  js.configs.recommended,
+  mochaPlugin.configs.flat.recommended,
+  prettierConfig,
+  {
+    plugins: {
+      mocha: mochaPlugin,
+      prettier: prettierPlugin,
+    },
+    languageOptions: {
+      ecmaVersion: 2022,
+      sourceType: "module",
+      globals: {
+        mocha: true,
+        ...globals.node,
+      },
+    },
+    rules: {
+      "prettier/prettier": ["error"],
+      "mocha/no-skipped-tests": ["error"],
+      "mocha/no-exclusive-tests": ["error"],
+    },
+  },
+];

package.json

@@ -4,10 +4,10 @@
   "description": "A command-line JSON and YAML validator that's on your wavelength",
   "scripts": {
     "test": "V8R_CACHE_NAME=v8r-test c8 --reporter=text mocha \"src/**/*.spec.js\"",
-    "lint": "eslint \"src/**/*.js\"",
+    "lint": "eslint \"**/*.{js,cjs}\"",
     "coverage": "c8 report --reporter=cobertura",
-    "prettier": "prettier --write \"**/*.js\"",
-    "prettier:check": "prettier --check \"**/*.js\"",
+    "prettier": "prettier --write \"**/*.{js,cjs}\"",
+    "prettier:check": "prettier --check \"**/*.{js,cjs}\"",
     "v8r": "src/index.js"
   },
   "bin": {