Switch to flat config

eslint.config.mjs

@@ -0,0 +1,56 @@
+import js from '@eslint/js'
+import globals from 'globals'
+
+/** @type {import('eslint').Linter.FlatConfig[]} */
+export default [
+  // global settings
+  {
+    ignores: [
+      '.cache/**',
+      '.netlify/**',
+      '_site/**',
+      'node_modules/**',
+      'resources/**'
+    ],
+    languageOptions: {
+      ecmaVersion: 2019,
+      sourceType: 'module',
+      globals: {
+        ...globals.browser
+      }
+    },
+    linterOptions: {
+      reportUnusedDisableDirectives: 'error'
+    }
+  },
+  js.configs.recommended,
+  {
+    files: [
+      '**/*.js',
+      '**/*.mjs'
+    ],
+    rules: {
+      'no-return-await': 'error',
+      'object-curly-spacing': [
+        'error',
+        'always'
+      ],
+      'prefer-template': 'error',
+      semi: [
+        'error',
+        'never'
+      ],
+      strict: 'error'
+    }
+  },
+  {
+    files: [
+      'scripts/**'
+    ],
+    languageOptions: {
+      globals: {
+        ...globals.nodeBuiltin
+      }
+    }
+  }
+]

package.json

@@ -24,7 +24,7 @@
     "serve": "hugo server --port 4000 --disableFastRender --noHTTPCache --renderToMemory --printPathWarnings --printUnusedTemplates",
     "serve-only": "npx sirv-cli _site --port 4000",
     "test": "npm-run-all build --parallel --continue-on-error --aggregate-output test-*",
-    "test-eslint": "cross-env ESLINT_USE_FLAT_CONFIG=false eslint --ignore-path .gitignore --cache --cache-location .cache/.eslintcache --report-unused-disable-directives --ext .js,.mjs .",
+    "test-eslint": "eslint --cache --cache-location .cache/.eslintcache .",
     "test-fusv": "fusv src/assets/scss/",
     "test-stylelint": "stylelint src/assets/scss/ --cache --cache-location .cache/.stylelintcache",
     "test-markdownlint": "markdownlint-cli2 \"**/*.md\" \"!**/node_modules/**\"",
@@ -34,12 +34,14 @@
     "netlify": "cross-env-shell HUGO_BASEURL=$DEPLOY_PRIME_URL npm run build"
   },
   "devDependencies": {
+    "@eslint/js": "^9.1.1",
     "autoprefixer": "^10.4.19",
     "bootstrap": "^5.3.3",
     "clipboard": "^2.0.11",
     "cross-env": "^7.0.3",
     "eslint": "^9.2.0",
     "find-unused-sass-variables": "^6.0.0",
+    "globals": "^14.0.0",
     "hugo-bin": "^0.122.7",
     "linkinator": "^6.0.4",
     "lockfile-lint": "^4.13.2",