Update to ESLint 9's "flat" configuration file format.

eslint.config.mjs

@@ -0,0 +1,61 @@
+import js from "@eslint/js";
+import eslintPluginJsdoc from "eslint-plugin-jsdoc";
+import eslintPluginNode from "eslint-plugin-n";
+import eslintPluginUnicorn from "eslint-plugin-unicorn";
+
+export default [
+  js.configs.all,
+  eslintPluginJsdoc.configs['flat/recommended'],
+  eslintPluginNode.configs["flat/recommended"],
+  eslintPluginUnicorn.configs["flat/all"],
+  {
+    "ignores": [
+      "test/*/**",
+      "webworker/markdownlint-cli2-webworker.js",
+      "webworker/setImmediate.js"
+    ]
+  },
+  {
+    "languageOptions": {
+      "sourceType": "commonjs"
+    },
+    "linterOptions": {
+      "reportUnusedDisableDirectives": true
+    },
+    "rules": {
+      "capitalized-comments": "off",
+      "complexity": "off",
+      "guard-for-in": "off",
+      "id-length": "off",
+      "max-lines-per-function": "off",
+      "max-lines": "off",
+      "max-params": "off",
+      "max-statements": "off",
+      "multiline-comment-style": [ "error", "separate-lines" ],
+      "no-console": "off",
+      "no-magic-numbers": "off",
+      "no-plusplus": "off",
+      "no-ternary": "off",
+      "no-undef-init": "off",
+      "no-undefined": "off",
+      "no-useless-assignment": "off",
+      "one-var": "off",
+      "require-atomic-updates": "off",
+      "sort-keys": "off",
+      "sort-imports": "off",
+
+      "unicorn/no-null": "off",
+      "unicorn/prefer-module": "off",
+      "unicorn/prefer-string-replace-all": "off",
+      "unicorn/prevent-abbreviations": "off"
+    }
+  },
+  {
+    "files": [
+      "**/*.mjs"
+    ],
+    "languageOptions": {
+      "sourceType": "module"
+    }
+  }
+];

package.json

@@ -31,7 +31,7 @@
     "build-docker-image": "VERSION=$(node -e \"process.stdout.write(require('./package.json').version)\") && docker build -t davidanson/markdownlint-cli2:v$VERSION -f docker/Dockerfile --label org.opencontainers.image.version=v$VERSION .",
     "build-docker-image-rules": "VERSION=$(node -e \"process.stdout.write(require('./package.json').version)\") && docker build -t davidanson/markdownlint-cli2-rules:v$VERSION -f docker/Dockerfile-rules --build-arg VERSION=v$VERSION --label org.opencontainers.image.version=v$VERSION .",
     "ci": "npm-run-all --continue-on-error --parallel test-cover lint schema && git diff --exit-code",
-    "lint": "eslint --max-warnings 0 --no-eslintrc --config .eslintrc.json .",
+    "lint": "eslint --max-warnings 0",
     "lint-dockerfile": "docker run --rm -i hadolint/hadolint:latest-alpine < docker/Dockerfile",
     "lint-watch": "git ls-files | entr npm run lint",
     "schema": "cpy ./node_modules/markdownlint/schema/markdownlint-config-schema.json ./schema --flat",
@@ -76,6 +76,7 @@
     "micromatch": "4.0.5"
   },
   "devDependencies": {
+    "@eslint/js": "9.1.1",
     "@iktakahiro/markdown-it-katex": "4.0.1",
     "ajv": "8.12.0",
     "ava": "6.1.2",

test/fs-mock.js

@@ -1,7 +1,5 @@
 // @ts-check
 
-/* eslint-disable n/prefer-promises/fs */
-
 "use strict";
 
 const fs = require("node:fs");

webworker/webworker-test.js

@@ -1,7 +1,6 @@
 "use strict";
 
-/* eslint-env qunit */
-/* globals markdownlintCli2, FsVirtual */
+/* globals markdownlintCli2, FsVirtual, QUnit */
 
 const md009 = "# Title\n\nText \n";
 const md010 = "# Title\n\n\tText\n";