new-for-builtins: Correct fix for Date() (#2543)

Author: fisker

docs/rules/new-for-builtins.md

@@ -2,7 +2,7 @@
 
 💼 This rule is enabled in the ✅ `recommended` [config](https://github.com/sindresorhus/eslint-plugin-unicorn#preset-configs-eslintconfigjs).
 
-🔧 This rule is automatically fixable by the [`--fix` CLI option](https://eslint.org/docs/latest/user-guide/command-line-interface#--fix).
+🔧💡 This rule is automatically fixable by the [`--fix` CLI option](https://eslint.org/docs/latest/user-guide/command-line-interface#--fix) and manually fixable by [editor suggestions](https://eslint.org/docs/latest/use/core-concepts#rule-suggestions).
 
 <!-- end auto-generated rule header -->
 <!-- Do not manually modify this header. Run: `npm run fix:eslint-docs` -->

readme.md

@@ -71,7 +71,7 @@ export default [
 | [explicit-length-check](docs/rules/explicit-length-check.md)                                     | Enforce explicitly comparing the `length` or `size` property of a value.                                                                                                                                          | ✅  | 🔧 | 💡 |
 | [filename-case](docs/rules/filename-case.md)                                                     | Enforce a case style for filenames.                                                                                                                                                                               | ✅  |    |    |
 | [import-style](docs/rules/import-style.md)                                                       | Enforce specific import styles per module.                                                                                                                                                                        | ✅  |    |    |
-| [new-for-builtins](docs/rules/new-for-builtins.md)                                               | Enforce the use of `new` for all builtins, except `String`, `Number`, `Boolean`, `Symbol` and `BigInt`.                                                                                                           | ✅  | 🔧 |    |
+| [new-for-builtins](docs/rules/new-for-builtins.md)                                               | Enforce the use of `new` for all builtins, except `String`, `Number`, `Boolean`, `Symbol` and `BigInt`.                                                                                                           | ✅  | 🔧 | 💡 |
 | [no-abusive-eslint-disable](docs/rules/no-abusive-eslint-disable.md)                             | Enforce specifying rules to disable in `eslint-disable` comments.                                                                                                                                                 | ✅  |    |    |
 | [no-accessor-recursion](docs/rules/no-accessor-recursion.md)                                     | Disallow recursive access to `this` within getters and setters.                                                                                                                                                   | ✅  |    |    |
 | [no-anonymous-default-export](docs/rules/no-anonymous-default-export.md)                         | Disallow anonymous functions and classes as the default export.                                                                                                                                                   | ✅  |    | 💡 |

rules/new-for-builtins.js

@@ -1,10 +1,19 @@
 import {GlobalReferenceTracker} from './utils/global-reference-tracker.js';
 import * as builtins from './utils/builtins.js';
-import {switchCallExpressionToNewExpression, switchNewExpressionToCallExpression} from './fix/index.js';
+import {
+	switchCallExpressionToNewExpression,
+	switchNewExpressionToCallExpression,
+	fixSpaceAroundKeyword,
+} from './fix/index.js';
+
+const MESSAGE_ID_ERROR_DATE = 'error-date';
+const MESSAGE_ID_SUGGESTION_DATE = 'suggestion-date';
 
 const messages = {
 	enforce: 'Use `new {{name}}()` instead of `{{name}}()`.',
 	disallow: 'Use `{{name}}()` instead of `new {{name}}()`.',
+	[MESSAGE_ID_ERROR_DATE]: 'Use `String(new Date())` instead of `Date()`.',
+	[MESSAGE_ID_SUGGESTION_DATE]: 'Switch to `String(new Date())`.',
 };
 
 function enforceNewExpression({node, path: [name]}, sourceCode) {
@@ -19,6 +28,33 @@ function enforceNewExpression({node, path: [name]}, sourceCode) {
 		}
 	}
 
+	// `Date()` returns a string representation of the current date and time, exactly as `new Date().toString()` does.
+	// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/Date#return_value
+	if (name === 'Date') {
+		function * fix(fixer) {
+			yield fixer.replaceText(node, 'String(new Date())');
+			yield * fixSpaceAroundKeyword(fixer, node, sourceCode);
+		}
+
+		const problem = {
+			node,
+			messageId: MESSAGE_ID_ERROR_DATE,
+		};
+
+		if (sourceCode.getCommentsInside(node).length === 0 && node.arguments.length === 0) {
+			problem.fix = fix;
+		} else {
+			problem.suggest = [
+				{
+					messageId: MESSAGE_ID_SUGGESTION_DATE,
+					fix,
+				},
+			];
+		}
+
+		return problem;
+	}
+
 	return {
 		node,
 		messageId: 'enforce',
@@ -77,6 +113,7 @@ const config = {
 			recommended: true,
 		},
 		fixable: 'code',
+		hasSuggestions: true,
 		messages,
 	},
 };

test/new-for-builtins.js

@@ -13,7 +13,6 @@ test.snapshot({
 		'const foo = new BigInt64Array()',
 		'const foo = new BigUint64Array()',
 		'const foo = new DataView()',
-		'const foo = new Date()',
 		'const foo = new Error()',
 		'const foo = new Float32Array()',
 		'const foo = new Float64Array()',
@@ -205,7 +204,6 @@ test.snapshot({
 		'const foo = BigInt64Array()',
 		'const foo = BigUint64Array()',
 		'const foo = DataView()',
-		'const foo = Date()',
 		'const foo = Error()',
 		'const foo = Error(\'Foo bar\')',
 		'const foo = Float32Array()',
@@ -259,3 +257,22 @@ test.snapshot({
 		`,
 	],
 });
+
+// `Date`
+test.snapshot({
+	valid: [
+		'const foo = new Date();',
+	],
+	invalid: [
+		'const foo = Date();',
+		'const foo = globalThis.Date();',
+		outdent`
+			function foo() {
+				return(globalThis).Date();
+			}
+		`,
+		'const foo = Date(/*comment*/);',
+		'const foo = globalThis/*comment*/.Date();',
+		'const foo = Date(bar);',
+	],
+});