chore: migrate to eslint flat configs

.github/CODEOWNERS

@@ -42,7 +42,6 @@
 /typings @microsoft/fluentui-react-build
 
 #### Root Build files
-/.eslintrc.* @microsoft/fluentui-react-build
 /.yarnrc @microsoft/fluentui-react-build
 /.gitattributes @microsoft/fluentui-react-build
 /.gitignore @microsoft/fluentui-react-build
@@ -399,8 +398,9 @@ packages/react-experiments/src/components/TileList @ThomasMichon
 **/just.config.ts @microsoft/fluentui-react-build
 **/jest.config.js @microsoft/fluentui-react-build
 **/webpack.*.js @microsoft/fluentui-react-build
-**/.eslintrc.js @microsoft/fluentui-react-build
-**/.eslintrc.json @microsoft/fluentui-react-build
+**/eslint.config.js @microsoft/fluentui-react-build
+**/eslint.config.cjs @microsoft/fluentui-react-build
+**/eslint.config.mjs @microsoft/fluentui-react-build
 **/tsconfig.json @microsoft/fluentui-react-build
 **/tsconfig.lib.json @microsoft/fluentui-react-build
 **/tsconfig.spec.json @microsoft/fluentui-react-build

change/@fluentui-tokens-6e67aa3e-9b31-4d76-a1a1-8e891bbfa643.json

@@ -0,0 +1,7 @@
+{
+  "type": "none",
+  "comment": "chore: migrate to new eslint flat config format",
+  "packageName": "@fluentui/tokens",
+  "email": "vgenaev@gmail.com",
+  "dependentChangeType": "none"
+}

change/@fluentui-web-components-3349be97-7f32-49ff-bc78-1f2ff01d94b5.json

@@ -0,0 +1,7 @@
+{
+  "type": "none",
+  "comment": "chore: update verify-packaging script to exclude root eslintrc file",
+  "packageName": "@fluentui/web-components",
+  "email": "vgenaev@gmail.com",
+  "dependentChangeType": "none"
+}

change/@fluentui-webpack-utilities-548f764d-130b-4ce2-b7ef-fb3b4ff26403.json

@@ -0,0 +1,7 @@
+{
+  "type": "none",
+  "comment": "chore: migrate to new eslint flat config format",
+  "packageName": "@fluentui/webpack-utilities",
+  "email": "vgenaev@gmail.com",
+  "dependentChangeType": "none"
+}

eslint.config.js

@@ -0,0 +1,13 @@
+// @ts-check
+
+/**
+ * Root ESLint configuration for Fluent UI monorepo
+ *
+ * - Root config provides base rules for react-components (v9) packages
+ * - v9 packages extend this config and add overrides as needed
+ * - v8 and other legacy packages maintain their own independent configs
+ */
+
+const fluentPlugin = require('@fluentui/eslint-plugin');
+
+module.exports = fluentPlugin.configs['flat/react'];

nx.json

@@ -68,14 +68,9 @@
       "executor": "nx:run-commands",
       "dependsOn": ["build"],
       "cache": true,
-      "inputs": [
-        "default",
-        "{workspaceRoot}/.eslintrc.json",
-        "{workspaceRoot}/.eslintignore",
-        "{workspaceRoot}/eslint.config.js"
-      ],
+      "inputs": ["default", "{workspaceRoot/eslint.config.js}"],
       "options": {
-        "command": "cross-env ESLINT_USE_FLAT_CONFIG=false eslint src"
+        "command": "eslint src"
       }
     },
     "format": {

packages/codemods/eslint.config.js

@@ -0,0 +1,25 @@
+// @ts-check
+const fluentPlugin = require('@fluentui/eslint-plugin');
+
+/** @type {import("eslint").Linter.Config[]} */
+module.exports = [
+  ...fluentPlugin.configs['flat/node'],
+  ...fluentPlugin.configs['flat/react-legacy'],
+  {
+    files: ['./src/**/*.{ts,tsx,js}'],
+    rules: {
+      '@typescript-eslint/naming-convention': 'off',
+      '@typescript-eslint/explicit-module-boundary-types': 'off',
+    },
+  },
+  {
+    files: ['./src/codeMods/tests/mock/**/*.{ts,tsx}'],
+    rules: {
+      '@typescript-eslint/ban-ts-comment': 'off',
+      '@typescript-eslint/no-explicit-any': 'off',
+      '@typescript-eslint/naming-convention': 'off',
+      'import/no-extraneous-dependencies': 'off',
+      '@typescript-eslint/no-deprecated': 'off',
+    },
+  },
+];

packages/react-components/component-selector-preview/library/eslint.config.js

@@ -1,5 +1,5 @@
 // @ts-check
 
-const fluentPlugin = require('@fluentui/eslint-plugin');
+const rootConfig = require('../../../../eslint.config.js');
 
-module.exports = [...fluentPlugin.configs['flat/react']];
+module.exports = [...rootConfig];

packages/react-components/component-selector-preview/stories/eslint.config.js

@@ -1,10 +1,10 @@
 // @ts-check
 
 const { defineConfig } = require('eslint/config');
-const fluentPlugin = require('@fluentui/eslint-plugin');
+const rootConfig = require('../../../../eslint.config.js');
 
 module.exports = defineConfig([
-  ...fluentPlugin.configs['flat/react'],
+  ...rootConfig,
   {
     rules: {
       'import/no-extraneous-dependencies': [

packages/react-components/deprecated/react-alert/eslint.config.js

@@ -1,5 +1,5 @@
 // @ts-check
 
-const fluentPlugin = require('@fluentui/eslint-plugin');
+const rootConfig = require('../../../../eslint.config.js');
 
-module.exports = [...fluentPlugin.configs['flat/react']];
+module.exports = [...rootConfig];

packages/react-components/deprecated/react-infobutton/eslint.config.js

@@ -1,5 +1,5 @@
 // @ts-check
 
-const fluentPlugin = require('@fluentui/eslint-plugin');
+const rootConfig = require('../../../../eslint.config.js');
 
-module.exports = [...fluentPlugin.configs['flat/react']];
+module.exports = [...rootConfig];

packages/react-components/deprecated/react-virtualizer/eslint.config.js

@@ -1,9 +1,9 @@
 // @ts-check
 
-const fluentPlugin = require('@fluentui/eslint-plugin');
+const rootConfig = require('../../../../eslint.config.js');
 
 module.exports = [
-  ...fluentPlugin.configs['flat/react'],
+  ...rootConfig,
   {
     rules: {
       '@typescript-eslint/no-deprecated': 'off',

packages/react-components/global-context/eslint.config.js

@@ -1,5 +1,5 @@
 // @ts-check
 
-const fluentPlugin = require('@fluentui/eslint-plugin');
+const rootConfig = require('../../../eslint.config.js');
 
-module.exports = [...fluentPlugin.configs['flat/react']];
+module.exports = [...rootConfig];

packages/react-components/keyboard-keys/eslint.config.js

@@ -1,5 +1,5 @@
 // @ts-check
 
-const fluentPlugin = require('@fluentui/eslint-plugin');
+const rootConfig = require('../../../eslint.config.js');
 
-module.exports = [...fluentPlugin.configs['flat/react']];
+module.exports = [...rootConfig];

packages/react-components/priority-overflow/eslint.config.js

@@ -1,5 +1,5 @@
 // @ts-check
 
-const fluentPlugin = require('@fluentui/eslint-plugin');
+const rootConfig = require('../../../eslint.config.js');
 
-module.exports = [...fluentPlugin.configs['flat/react']];
+module.exports = [...rootConfig];

packages/react-components/react-accordion/library/eslint.config.js

@@ -1,5 +1,5 @@
 // @ts-check
 
-const fluentPlugin = require('@fluentui/eslint-plugin');
+const rootConfig = require('../../../../eslint.config.js');
 
-module.exports = [...fluentPlugin.configs['flat/react']];
+module.exports = [...rootConfig];

packages/react-components/react-accordion/stories/eslint.config.js

@@ -1,10 +1,10 @@
 // @ts-check
 
 const { defineConfig } = require('eslint/config');
-const fluentPlugin = require('@fluentui/eslint-plugin');
+const rootConfig = require('../../../../eslint.config.js');
 
 module.exports = defineConfig([
-  ...fluentPlugin.configs['flat/react'],
+  ...rootConfig,
   {
     rules: {
       'import/no-extraneous-dependencies': [

packages/react-components/react-aria/library/eslint.config.js

@@ -1,5 +1,5 @@
 // @ts-check
 
-const fluentPlugin = require('@fluentui/eslint-plugin');
+const rootConfig = require('../../../../eslint.config.js');
 
-module.exports = [...fluentPlugin.configs['flat/react']];
+module.exports = [...rootConfig];

packages/react-components/react-aria/stories/eslint.config.js

@@ -1,10 +1,10 @@
 // @ts-check
 
 const { defineConfig } = require('eslint/config');
-const fluentPlugin = require('@fluentui/eslint-plugin');
+const rootConfig = require('../../../../eslint.config.js');
 
 module.exports = defineConfig([
-  ...fluentPlugin.configs['flat/react'],
+  ...rootConfig,
   {
     rules: {
       'import/no-extraneous-dependencies': [

packages/react-components/react-avatar/library/eslint.config.js

@@ -1,5 +1,5 @@
 // @ts-check
 
-const fluentPlugin = require('@fluentui/eslint-plugin');
+const rootConfig = require('../../../../eslint.config.js');
 
-module.exports = [...fluentPlugin.configs['flat/react']];
+module.exports = [...rootConfig];

packages/react-components/react-avatar/stories/eslint.config.js

@@ -1,10 +1,10 @@
 // @ts-check
 
 const { defineConfig } = require('eslint/config');
-const fluentPlugin = require('@fluentui/eslint-plugin');
+const rootConfig = require('../../../../eslint.config.js');
 
 module.exports = defineConfig([
-  ...fluentPlugin.configs['flat/react'],
+  ...rootConfig,
   {
     rules: {
       'import/no-extraneous-dependencies': [

packages/react-components/react-badge/library/eslint.config.js

@@ -1,5 +1,5 @@
 // @ts-check
 
-const fluentPlugin = require('@fluentui/eslint-plugin');
+const rootConfig = require('../../../../eslint.config.js');
 
-module.exports = [...fluentPlugin.configs['flat/react']];
+module.exports = [...rootConfig];

packages/react-components/react-badge/stories/eslint.config.js

@@ -1,10 +1,10 @@
 // @ts-check
 
 const { defineConfig } = require('eslint/config');
-const fluentPlugin = require('@fluentui/eslint-plugin');
+const rootConfig = require('../../../../eslint.config.js');
 
 module.exports = defineConfig([
-  ...fluentPlugin.configs['flat/react'],
+  ...rootConfig,
   {
     rules: {
       'import/no-extraneous-dependencies': [

packages/react-components/react-breadcrumb/library/eslint.config.js

@@ -1,5 +1,5 @@
 // @ts-check
 
-const fluentPlugin = require('@fluentui/eslint-plugin');
+const rootConfig = require('../../../../eslint.config.js');
 
-module.exports = [...fluentPlugin.configs['flat/react']];
+module.exports = [...rootConfig];

packages/react-components/react-breadcrumb/stories/eslint.config.js

@@ -1,10 +1,10 @@
 // @ts-check
 
 const { defineConfig } = require('eslint/config');
-const fluentPlugin = require('@fluentui/eslint-plugin');
+const rootConfig = require('../../../../eslint.config.js');
 
 module.exports = defineConfig([
-  ...fluentPlugin.configs['flat/react'],
+  ...rootConfig,
   {
     rules: {
       'import/no-extraneous-dependencies': [

packages/react-components/react-button/library/eslint.config.js

@@ -1,5 +1,5 @@
 // @ts-check
 
-const fluentPlugin = require('@fluentui/eslint-plugin');
+const rootConfig = require('../../../../eslint.config.js');
 
-module.exports = [...fluentPlugin.configs['flat/react']];
+module.exports = [...rootConfig];

packages/react-components/react-button/stories/eslint.config.js

@@ -1,10 +1,10 @@
 // @ts-check
 
 const { defineConfig } = require('eslint/config');
-const fluentPlugin = require('@fluentui/eslint-plugin');
+const rootConfig = require('../../../../eslint.config.js');
 
 module.exports = defineConfig([
-  ...fluentPlugin.configs['flat/react'],
+  ...rootConfig,
   {
     rules: {
       'import/no-extraneous-dependencies': [

packages/react-components/react-calendar-compat/library/eslint.config.js

@@ -1,5 +1,5 @@
 // @ts-check
 
-const fluentPlugin = require('@fluentui/eslint-plugin');
+const rootConfig = require('../../../../eslint.config.js');
 
-module.exports = [...fluentPlugin.configs['flat/react']];
+module.exports = [...rootConfig];

packages/react-components/react-calendar-compat/stories/eslint.config.js

@@ -1,10 +1,10 @@
 // @ts-check
 
 const { defineConfig } = require('eslint/config');
-const fluentPlugin = require('@fluentui/eslint-plugin');
+const rootConfig = require('../../../../eslint.config.js');
 
 module.exports = defineConfig([
-  ...fluentPlugin.configs['flat/react'],
+  ...rootConfig,
   {
     rules: {
       'import/no-extraneous-dependencies': [

packages/react-components/react-card/library/eslint.config.js

@@ -1,5 +1,5 @@
 // @ts-check
 
-const fluentPlugin = require('@fluentui/eslint-plugin');
+const rootConfig = require('../../../../eslint.config.js');
 
-module.exports = [...fluentPlugin.configs['flat/react']];
+module.exports = [...rootConfig];

packages/react-components/react-card/stories/eslint.config.js

@@ -1,10 +1,10 @@
 // @ts-check
 
 const { defineConfig } = require('eslint/config');
-const fluentPlugin = require('@fluentui/eslint-plugin');
+const rootConfig = require('../../../../eslint.config.js');
 
 module.exports = defineConfig([
-  ...fluentPlugin.configs['flat/react'],
+  ...rootConfig,
   {
     rules: {
       'import/no-extraneous-dependencies': [