Migrate to ESLint 9

client-node-tests/eslint.config.js

@@ -0,0 +1,10 @@
+// @ts-check
+'use strict';
+
+const { createConfig } = require('../eslint.config.base.js');
+
+module.exports = createConfig(
+	['./src/tsconfig.json'],
+	undefined,
+	{}
+);

client-node-tests/package.json

@@ -20,7 +20,7 @@
 		"clean": "rimraf lib",
 		"compile": "tsc -b ./tsconfig.json",
 		"watch": "tsc -b ./tsconfig.watch.json -w",
-		"lint": "eslint --ext ts src",
+		"lint": "eslint src",
 		"test": "node ../build/bin/symlink-tests.js && node lib/runTests.js",
 		"all": "npm run clean && npm run compile && npm run lint && npm run test",
 		"symlink:publish": "node ../build/bin/symlink-client-tests-publish.js",

client/eslint.config.js

@@ -0,0 +1,10 @@
+// @ts-check
+'use strict';
+
+const { createConfig } = require('../eslint.config.base.js');
+
+module.exports = createConfig(
+	['src/browser/tsconfig.json', 'src/common/tsconfig.json', 'src/node/tsconfig.json'],
+	undefined,
+	{}
+);

client/package.json

@@ -51,7 +51,7 @@
 		"compile": "tsc -b ./tsconfig.json && shx cp src/node/terminateProcess.sh lib/node/terminateProcess.sh",
 		"compile:clean": "git clean -xfd . && npm install && npm run clean && npm run compile",
 		"watch": "tsc -b ./tsconfig.watch.json -w",
-		"lint": "eslint --ext ts src",
+		"lint": "eslint src",
 		"test": "cd ../client-node-tests && npm test && cd ../client",
 		"clean": "rimraf lib",
 		"all": "npm run clean && npm run compile && npm run lint && npm test",

eslint.config.base.js

@@ -0,0 +1,79 @@
+// @ts-check
+'use strict';
+
+const tseslint = require('typescript-eslint');
+const stylistic = require('@stylistic/eslint-plugin');
+const globals = require('globals');
+
+/**
+ * Creates an ESLint flat config array for a TypeScript package.
+ *
+ * @param {string[]} projects - tsconfig project paths (relative to the package root)
+ * @param {string[]} [ignores] - additional paths/globs to ignore
+ * @param {Record<string, unknown>} [extraRules] - package-specific rule overrides
+ * @returns {import('eslint').Linter.Config[]}
+ */
+function createConfig(projects, ignores, extraRules) {
+	return tseslint.config(
+		{
+			ignores: ['lib/**', 'dist/**', 'node_modules/**', ...(ignores ?? [])],
+		},
+		{
+			files: ['**/*.ts'],
+			extends: [tseslint.configs.base],
+			languageOptions: {
+				parserOptions: {
+					ecmaVersion: 6,
+					sourceType: 'module',
+					project: projects,
+					tsconfigRootDir: process.cwd(),
+				},
+				globals: {
+					...globals.node,
+				},
+			},
+			plugins: {
+				'@stylistic': stylistic,
+			},
+			rules: {
+				'@stylistic/semi': 'error',
+				'@stylistic/member-delimiter-style': ['error', {
+					multiline: { delimiter: 'semi', requireLast: true },
+					singleline: { delimiter: 'semi', requireLast: false },
+					multilineDetection: 'brackets',
+				}],
+				'@stylistic/indent': ['warn', 'tab', { SwitchCase: 1 }],
+				'@stylistic/no-extra-semi': 'warn',
+				'@stylistic/quotes': ['error', 'single', { allowTemplateLiterals: true }],
+				'@typescript-eslint/no-floating-promises': 'error',
+				'curly': 'warn',
+				'eqeqeq': 'error',
+				'constructor-super': 'warn',
+				'prefer-const': ['warn', { destructuring: 'all' }],
+				'no-caller': 'warn',
+				'no-case-declarations': 'warn',
+				'no-debugger': 'warn',
+				'no-duplicate-case': 'warn',
+				'no-duplicate-imports': 'warn',
+				'no-eval': 'warn',
+				'no-async-promise-executor': 'warn',
+				'no-new-wrappers': 'warn',
+				'no-redeclare': 'off',
+				'no-sparse-arrays': 'warn',
+				'no-throw-literal': 'warn',
+				'no-unsafe-finally': 'warn',
+				'no-unused-labels': 'warn',
+				'no-restricted-globals': ['warn', 'name', 'length', 'event', 'closed', 'external', 'status', 'origin', 'orientation', 'context'],
+				'no-var': 'warn',
+				'@typescript-eslint/naming-convention': ['warn', {
+					selector: 'class',
+					format: ['PascalCase'],
+					leadingUnderscore: 'allow',
+				}],
+				...extraRules,
+			},
+		},
+	);
+}
+
+module.exports = { createConfig };

eslint.config.js

@@ -0,0 +1,33 @@
+// @ts-check
+'use strict';
+
+const stylistic = require('@stylistic/eslint-plugin');
+const globals = require('globals');
+
+/** @type {import('eslint').Linter.Config[]} */
+module.exports = [
+	{
+		ignores: ['node_modules/**', 'lib/**', '**/.tsconfigrc.js'],
+	},
+	{
+		files: ['**/*.js'],
+		plugins: {
+			'@stylistic': stylistic,
+		},
+		languageOptions: {
+			ecmaVersion: 2020,
+			globals: {
+				...globals.commonjs,
+				...globals.es2015,
+			},
+		},
+		rules: {
+			'@stylistic/semi': 'error',
+			'@stylistic/no-extra-semi': 'warn',
+			'curly': 'warn',
+			'@stylistic/quotes': ['error', 'single', { allowTemplateLiterals: true }],
+			'eqeqeq': 'error',
+			'@stylistic/indent': ['warn', 'tab', { SwitchCase: 1 }],
+		},
+	},
+];

jsonrpc/eslint.config.js

@@ -0,0 +1,12 @@
+// @ts-check
+'use strict';
+
+const { createConfig } = require('../eslint.config.base.js');
+
+module.exports = createConfig(
+	['src/browser/tsconfig.json', 'src/browser/test/tsconfig.json', 'src/common/tsconfig.json', 'src/common/test/tsconfig.json', 'src/node/tsconfig.json', 'src/node/test/tsconfig.json'],
+	['dist/**'],
+	{
+		'no-console': 'error',
+	}
+);

jsonrpc/package.json

@@ -40,7 +40,7 @@
 		"compile": "tsc -b ./tsconfig.json",
 		"watch": "tsc -b ./tsconfig.watch.json -w",
 		"clean": "rimraf lib && rimraf dist",
-		"lint": "eslint --ext ts src",
+		"lint": "eslint src",
 		"test": "npm run test:node && npm run test:browser",
 		"test:node": "node ../node_modules/mocha/bin/_mocha",
 		"test:browser": "npm run webpack:test:silent && node ../build/bin/runBrowserTests.js  http://127.0.0.1:8080/jsonrpc/src/browser/test/",

jsonrpc/src/common/connection.ts

@@ -1566,7 +1566,6 @@ export function createMessageConnection(messageReader: MessageReader, messageWri
 			messageReader.listen(callback);
 		},
 		inspect: (): void => {
-			// eslint-disable-next-line no-console
 			RAL().console.log('inspect');
 		}
 	};

jsonrpc/src/common/events.ts

@@ -81,7 +81,6 @@ class CallbackList {
 			try {
 				ret.push(callbacks[i].apply(contexts[i], args));
 			} catch (e) {
-				// eslint-disable-next-line no-console
 				RAL().console.error(e);
 			}
 		}