Added test cases for the upcoming ESLint 9.0 version & move to latest lsp libs. (#1816)

Author: dbaeumer

README.md

@@ -23,13 +23,17 @@ This section describes major releases and their improvements. For a detailed lis
 
 From version 2.2.3 on forward odd minor or patch version numbers indicate an insider or pre-release. So versions `2.2.3`, `2.2.5` and `2.3.1` will all be pre-release versions. `2.2.10`, `2.4.10` and `3.0.0` will all be regular release versions.
 
-### Version 3.0.1 - pre-release
-
-- converted the server to use diagnostic pull instead of push.
-- files will be revalidated on focus gain.
+### Version 3.0.3 - pre-release
+
+- Support for the new ESLint flat config files has improved. The following changes have been implemented:
+  - To use flat config files it is recommended to use ESLint version 8.57.0 or above.
+  - There is a new `eslint.useFlatConfig` setting which is honored by ESLint version 8.57.0 and above. If one of those versions is used, the extension adheres to the [ESLint Flat config rollout plan](https://eslint.org/blog/2023/10/flat-config-rollout-plans/). The setting has the same meaning as the environment variable `ESLINT_USE_FLAT_CONFIG`.
+  - The experimental settings `eslint.experimental.useFlatConfig` is deprecated and should only be used for ESLint versions >= 8.21 < 8.57.0.
+- Converted the server to use diagnostic pull instead of push.
+- Files will be revalidated on focus gain.
 - Add a command `ESLint: Revalidate all open files` to revalidate all open files.
 - Probing support for [Astro](https://github.com/microsoft/vscode-eslint/pull/1795), [MDX](https://github.com/microsoft/vscode-eslint/pull/1794) and [JSON](https://github.com/microsoft/vscode-eslint/pull/1787)
-- various [bug fixes](https://github.com/microsoft/vscode-eslint/issues?q=is%3Aclosed+milestone%3ANext)
+- Various [bug fixes](https://github.com/microsoft/vscode-eslint/issues?q=is%3Aclosed+milestone%3ANext)
 
 ### Version 2.4.4
 

client/package-lock.json

@@ -20,7 +20,7 @@
 		"@types/vscode": "1.86.0"
 	},
 	"dependencies": {
-		"vscode-languageclient": "10.0.0-next.2"
+		"vscode-languageclient": "10.0.0-next.3"
 	},
 	"scripts": {
 		"test": "node ../node_modules/mocha/bin/_mocha",

client/package.json

@@ -2,7 +2,7 @@
 	"name": "vscode-eslint",
 	"displayName": "ESLint",
 	"description": "Integrates ESLint JavaScript into VS Code.",
-	"version": "3.0.1",
+	"version": "3.0.3",
 	"author": "Microsoft Corporation",
 	"license": "MIT",
 	"repository": {

package.json

@@ -0,0 +1,12 @@
+function bar() {
+	if (foo) {
+		foo++;
+	}
+}
+
+function foo(x) {
+	console.log(x);
+	bar();
+	var x = 10;
+	console.log(undef);
+}

playgrounds/9.0/flat/app.js

@@ -0,0 +1,58 @@
+const globals = require('globals');
+
+module.exports = [
+	{
+		files: ["**/*.js"],
+		languageOptions: {
+			sourceType: "module",
+			globals: {
+				...globals.browser,
+				...globals.node,
+				...globals.es6,
+				...globals.commonjs
+			}
+		},
+		rules: {
+			"no-use-before-define": "error",
+			"no-useless-escape": "error",
+			"no-const-assign": "warn",
+			"no-this-before-super": "warn",
+			"no-undef": "warn",
+			"no-unreachable": "warn",
+			"no-unused-vars": "warn",
+			"constructor-super": "warn",
+			"valid-typeof": "warn",
+			"no-extra-semi": "warn",
+			"curly": "warn",
+			"no-console": [
+				2,
+				{
+					"allow": [
+						"warn",
+						"error"
+					]
+				}
+			],
+			"eqeqeq": [
+				"error",
+				"always",
+				{
+					"null": "ignore"
+				}
+			],
+			"indent": [
+				"warn",
+				"tab",
+				{
+					"VariableDeclarator": {
+						"var": 2,
+						"let": 2,
+						"const": 3
+					},
+					"MemberExpression": 1,
+					"SwitchCase": 1
+				}
+			]
+		}
+	}
+]