Require ESLint 8 (#1724)

configs/recommended.js

@@ -1,7 +1,7 @@
 'use strict';
 module.exports = {
 	env: {
-		es6: true,
+		es2021: true,
 	},
 	parserOptions: {
 		ecmaVersion: 'latest',

package.json

@@ -71,7 +71,7 @@
 		"c8": "^7.11.0",
 		"chalk": "^5.0.0",
 		"enquirer": "^2.3.6",
-		"eslint": "^8.6.0",
+		"eslint": "^8.8.0",
 		"eslint-ava-rule-tester": "^4.0.0",
 		"eslint-plugin-eslint-plugin": "^4.1.0",
 		"eslint-plugin-internal-rules": "file:./scripts/internal-rules/",
@@ -90,7 +90,7 @@
 		"xo": "^0.47.0"
 	},
 	"peerDependencies": {
-		"eslint": ">=7.32.0"
+		"eslint": ">=8.8.0"
 	},
 	"ava": {
 		"files": [

readme.md

@@ -24,7 +24,7 @@ Use a [preset config](#preset-configs) or configure each rules in `package.json`
 	"name": "my-awesome-project",
 	"eslintConfig": {
 		"env": {
-			"es6": true
+			"es2021": true
 		},
 		"parserOptions": {
 			"ecmaVersion": "latest",

test/package.mjs

@@ -2,6 +2,7 @@ import fs, {promises as fsAsync} from 'node:fs';
 import path from 'node:path';
 import test from 'ava';
 import {ESLint} from 'eslint';
+import * as eslintrc from '@eslint/eslintrc';
 import eslintPluginUnicorn from '../index.js';
 import {RULE_NOTICE_MARK, getRuleNoticesSectionBody} from '../scripts/rule-notices.mjs';
 import {RULES_TABLE_MARK, getRulesTable} from '../scripts/rules-table.mjs';
@@ -121,6 +122,68 @@ test('validate configuration', async t => {
 			`Configuration for "${name}" is invalid.`,
 		);
 	}
+
+	// `env`
+	{
+		// https://github.com/eslint/eslint/blob/32ac37a76b2e009a8f106229bc7732671d358189/conf/globals.js#L19
+		const testObjects = [
+			'undefinedGlobalObject',
+			// `es3`
+			'Array',
+			// `es5`
+			'JSON',
+			// `es2015`(`es6`)
+			'Promise',
+			// `es2021`
+			'WeakRef',
+		];
+		const baseOptions = {
+			useEslintrc: false,
+			plugins: {
+				unicorn: eslintPluginUnicorn,
+			},
+			overrideConfig: {
+				rules: {
+					'no-undef': 'error',
+				},
+			},
+		};
+		const getUndefinedGlobals = async options => {
+			const [{messages}] = await new ESLint({...baseOptions, ...options}).lintText(testObjects.join(';\n'));
+			return messages.map(({message}) => message.match(/^'(?<object>.*)' is not defined\.$/).groups.object);
+		};
+
+		t.deepEqual(await getUndefinedGlobals(), ['undefinedGlobalObject', 'Promise', 'WeakRef']);
+		t.deepEqual(await getUndefinedGlobals({baseConfig: eslintPluginUnicorn.configs.recommended}), ['undefinedGlobalObject']);
+
+		const availableEnvironments = [...eslintrc.Legacy.environments.keys()].filter(name => /^es\d+$/.test(name));
+		const recommendedEnvironments = Object.keys(eslintPluginUnicorn.configs.recommended.env);
+		t.is(recommendedEnvironments.length, 1);
+		t.is(
+			availableEnvironments[availableEnvironments.length - 1],
+			recommendedEnvironments[0],
+			'env should be the latest es version',
+		);
+	}
+
+	// `sourceType`
+	{
+		const text = 'import fs from "node:fs";';
+		const baseOptions = {
+			useEslintrc: false,
+			plugins: {
+				unicorn: eslintPluginUnicorn,
+			},
+		};
+		const runEslint = async options => {
+			const [{messages}] = await new ESLint({...baseOptions, ...options}).lintText(text);
+			return messages;
+		};
+
+		const [{message}] = await runEslint();
+		t.is(message, 'Parsing error: The keyword \'import\' is reserved');
+		t.deepEqual(await runEslint({baseConfig: eslintPluginUnicorn.configs.recommended}), []);
+	}
 });
 
 test('Every rule is defined in readme.md usage and list of rules in alphabetical order', async t => {