no-object-as-default-parameter: Forbid destructuring (#1433)

Author: fisker

docs/rules/no-object-as-default-parameter.md

@@ -2,13 +2,16 @@
 
 Default parameters should not be passed to a function through an object literal. The `foo = {a: false}` parameter works fine if only used with one option. As soon as additional options are added, you risk replacing the whole `foo = {a: false, b: true}` object when passing only one option: `{a: true}`. For this reason, object destructuring should be used instead.
 
-
 ## Fail
 
 ```js
 const abc = (foo = {a: false}) => {};
 ```
 
+```js
+function foo({a} = {a: false}) {}
+```
+
 ```js
 const abc = (foo = {a: false, b: 123}) => {};
 ```
@@ -20,6 +23,12 @@ const abc = (foo = {a: false, b: 123}) => {};
 const abc = (foo = {}) => {};
 ```
 
+```js
+function foo(options) {
+	const {a} = {a: false, ...options};
+}
+```
+
 ```js
 const abc = (foo = false) => {};
 ```

rules/no-object-as-default-parameter.js

@@ -1,24 +1,34 @@
 'use strict';
 
-const MESSAGE_ID = 'noObjectAsDefaultParameter';
+const MESSAGE_ID_IDENTIFIER = 'identifier';
+const MESSAGE_ID_NON_IDENTIFIER = 'non-identifier';
 const messages = {
-	[MESSAGE_ID]: 'Do not use an object literal as default for parameter `{{parameter}}`.',
+	[MESSAGE_ID_IDENTIFIER]: 'Do not use an object literal as default for parameter `{{parameter}}`.',
+	[MESSAGE_ID_NON_IDENTIFIER]: 'Do not use an object literal as default.',
 };
 
 const objectParameterSelector = [
 	':function > AssignmentPattern.params',
-	'[left.type="Identifier"]',
 	'[right.type="ObjectExpression"]',
 	'[right.properties.length>0]',
 ].join('');
 
 const create = () => {
 	return {
 		[objectParameterSelector]: node => {
+			const {left, right} = node;
+
+			if (left.type === 'Identifier') {
+				return {
+					node: left,
+					messageId: MESSAGE_ID_IDENTIFIER,
+					data: {parameter: left.name},
+				};
+			}
+
 			return {
-				node: node.left,
-				messageId: MESSAGE_ID,
-				data: {parameter: node.left.name},
+				node: right,
+				messageId: MESSAGE_ID_NON_IDENTIFIER,
 			};
 		},
 	};

test/no-object-as-default-parameter.mjs

@@ -4,10 +4,14 @@ import {getTester} from './utils/test.mjs';
 const {test} = getTester(import.meta);
 
 const error = {
-	messageId: 'noObjectAsDefaultParameter',
+	messageId: 'identifier',
 	data: {parameter: 'foo'},
 };
 
+const errorNonIdentifier = {
+	messageId: 'non-identifier',
+};
+
 test({
 	valid: [
 		'const abc = {};',
@@ -160,6 +164,14 @@ test({
 			`,
 			errors: [error],
 		},
+		{
+			code: outdent`
+				const A = class {
+					abc({a} = {a: 123}) {}
+				}
+			`,
+			errors: [errorNonIdentifier],
+		},
 	],
 });
 
@@ -168,5 +180,7 @@ test.snapshot({
 	invalid: [
 		'function abc(foo = {a: 123}) {}',
 		'const abc = (foo = {a: false}) => {};',
+		'function abc({a} = {a: 123}) {}',
+		'function abc([a] = {a: 123}) {}',
 	],
 });

test/snapshots/no-object-as-default-parameter.mjs.md

@@ -23,3 +23,23 @@ Generated by [AVA](https://avajs.dev).
     > 1 | const abc = (foo = {a: false}) => {};␊
         |              ^^^ Do not use an object literal as default for parameter \`foo\`.␊
     `
+
+## Invalid #3
+      1 | function abc({a} = {a: 123}) {}
+
+> Error 1/1
+
+    `␊
+    > 1 | function abc({a} = {a: 123}) {}␊
+        |                    ^^^^^^^^ Do not use an object literal as default.␊
+    `
+
+## Invalid #4
+      1 | function abc([a] = {a: 123}) {}
+
+> Error 1/1
+
+    `␊
+    > 1 | function abc([a] = {a: 123}) {}␊
+        |                    ^^^^^^^^ Do not use an object literal as default.␊
+    `