upgrade eslint & re-lint code

bench/index.js

@@ -5,7 +5,7 @@ const benches = []
 const mapObjRefA = {}
 const mapObjRefB = {}
 function getArguments() {
-  return arguments // eslint-disable-line prefer-rest-params
+  return arguments  
 }
 class A {}
 const fixtures = {

eslint.config.js

@@ -0,0 +1,41 @@
+import eslintjs from '@eslint/js'
+
+const { configs: eslintConfigs } = eslintjs
+
+export default [
+  eslintConfigs['recommended'],
+  {
+    languageOptions: {
+      globals: {
+        Buffer: false,
+        process: false,
+        document: false,
+        window: false,
+        global: false,
+      }
+    },
+    rules: {
+      'no-unused-vars': [
+        'error',
+        {
+          argsIgnorePattern: '^_',
+          caughtErrorsIgnorePattern: '^_',
+        },
+      ],
+    },
+  },
+  {
+    files: ['test/*', 'bench/*'],
+    languageOptions: {
+      // if we ever use more globals than this, pull in the `globals` package
+      globals: {
+        Buffer: false,
+        process: false,
+        console: false,
+        describe: false,
+        beforeEach: false,
+        it: false,
+      }
+    },
+  },
+]