switched to new eslint config format

defaults/js-eslint-standard.mjs

@@ -0,0 +1,29 @@
+import globals from "globals";
+
+export default [{
+    languageOptions: {
+        globals: {
+            ...globals.browser,
+            ...globals.node,
+        },
+
+        ecmaVersion: "latest",
+        sourceType: "module",
+    },
+
+    rules: {
+        "no-console": "error",
+        "no-undef": "error",
+        "no-unused-vars": ["error", {
+            vars: "all",
+            args: "after-used",
+            ignoreRestSiblings: false,
+        }],
+        eqeqeq: ["error", "always"],
+        semi: "off",
+        quotes: "off",
+        indent: "off",
+        "comma-dangle": "off",
+        "space-before-function-paren": "off",
+    },
+}];

package.json

@@ -17,6 +17,7 @@
     "sitespeed.io": "36.4.1",
     "stylelint": "16.14.1",
     "eslint": "9.21.0",
+    "globals": "14.0.0",
     "vnu-jar": "23.4.11",
     "webperf-sitespeedio-plugin": "2025.2.0",
     "yellowlabtools": "3.0.1"

tests/lint_base.py

@@ -98,7 +98,7 @@ def get_errors(test_type, params):
             f"node node_modules{os.path.sep}stylelint{os.path.sep}bin"
             f"{os.path.sep}stylelint.mjs {arg}")
     elif is_js:
-        config_file_path = os.path.join(base_directory, "defaults", "js-eslint-standard.json")
+        config_file_path = os.path.join(base_directory, "defaults", "js-eslint-standard.mjs")
         arg = f'{file_path} -f json -o {lint_file_path} --config {config_file_path} --quiet'
         command = (
             f"node node_modules{os.path.sep}eslint{os.path.sep}bin"