From de2865911a570a062dd1d832dca68079934b9ebe Mon Sep 17 00:00:00 2001
From: fisker Cheung <lionkay@gmail.com>
Date: Mon, 7 Nov 2022 17:08:18 +0800
Subject: [PATCH 01/12] Basic

---
 configs/recommended.js                  |   1 +
 docs/rules/prefer-set-size.md           |  16 +++++
 rules/prefer-set-size.js                |  87 ++++++++++++++++++++++++
 test/prefer-set-size.mjs                |  25 +++++++
 test/snapshots/prefer-set-size.mjs.md   |  21 ++++++
 test/snapshots/prefer-set-size.mjs.snap | Bin 0 -> 175 bytes
 6 files changed, 150 insertions(+)
 create mode 100644 docs/rules/prefer-set-size.md
 create mode 100644 rules/prefer-set-size.js
 create mode 100644 test/prefer-set-size.mjs
 create mode 100644 test/snapshots/prefer-set-size.mjs.md
 create mode 100644 test/snapshots/prefer-set-size.mjs.snap

diff --git a/configs/recommended.js b/configs/recommended.js
index 2e7ffd8713..a1d26d031a 100644
--- a/configs/recommended.js
+++ b/configs/recommended.js
@@ -101,6 +101,7 @@ module.exports = {
 		'unicorn/prefer-reflect-apply': 'error',
 		'unicorn/prefer-regexp-test': 'error',
 		'unicorn/prefer-set-has': 'error',
+		'unicorn/prefer-set-size': 'error',
 		'unicorn/prefer-spread': 'error',
 		// TODO: Enable this by default when targeting Node.js 16.
 		'unicorn/prefer-string-replace-all': 'off',
diff --git a/docs/rules/prefer-set-size.md b/docs/rules/prefer-set-size.md
new file mode 100644
index 0000000000..70070de78b
--- /dev/null
+++ b/docs/rules/prefer-set-size.md
@@ -0,0 +1,16 @@
+<!-- end auto-generated rule header -->
+<!-- Do not manually modify this header. Run: `npm run fix:eslint-docs` -->
+
+<!-- Remove this comment, add more detailed description. -->
+
+## Fail
+
+```js
+const foo = 'unicorn';
+```
+
+## Pass
+
+```js
+const foo = '🦄';
+```
diff --git a/rules/prefer-set-size.js b/rules/prefer-set-size.js
new file mode 100644
index 0000000000..85a278cb5f
--- /dev/null
+++ b/rules/prefer-set-size.js
@@ -0,0 +1,87 @@
+'use strict';
+const {
+	memberExpressionSelector,
+	newExpressionSelector,
+} = require('./selectors/index.js');
+const {} = require('./fix/index.js');
+const { findVariable } = require('eslint-utils');
+
+const MESSAGE_ID = 'prefer-set-size';
+const messages = {
+	[MESSAGE_ID]: 'Prefer use `Set#size`.'
+}
+
+const lengthAccessSelector = [
+	memberExpressionSelector('length'),
+	'[object.type="ArrayExpression"]',
+	'[object.elements.length=1]',
+	'[object.elements.0.type="SpreadElement"]',
+].join('');
+
+const isNewSet = node =>
+	node.type === 'NewExpression'
+	&& node.callee.type === 'Identifier'
+	&& node.callee.name === 'Set';
+
+function isSet(node, scope) {
+	if (isNewSet(node)) {
+		return true;
+	}
+
+
+	if (node.type !== 'Identifier') {
+		return false;
+	}
+
+	const variable = findVariable(scope, maybeSet);
+}
+
+
+// `[...set].length` -> `set.size`
+function fix(sourceCode, lengthAccessNodes) {
+	const {
+		object: arrayExpression,
+		property
+	} = lengthAccessNodes;
+	const set = arrayExpression.elements[0].argument;
+
+	/** @param {import('eslint').Rule.RuleFixer} fixer */
+	return function * (fixer) {
+		yield fixer.replaceText(property, 'size');
+		yield fixer.replaceText(arrayExpression, sourceCode.getText(set));
+	}
+}
+
+/** @param {import('eslint').Rule.RuleContext} context */
+const create = context => {
+	const sourceCode = context.getSourceCode();
+
+	return {
+		[lengthAccessSelector](node) {
+			const maybeSet = node.object.elements[0].argument;
+			if (!isSet(maybeSet, context.getScope())) {
+				return;
+			}
+
+			return {
+				node: node.property,
+				messageId: MESSAGE_ID,
+				fix: fix(sourceCode, node),
+			}
+		}
+	};
+};
+
+/** @type {import('eslint').Rule.RuleModule} */
+module.exports = {
+	create,
+	meta: {
+		type: 'suggestion',
+		docs: {
+			description: 'Prefer use `Set#size` instead of `Array#length`.',
+		},
+		fixable: 'code',
+
+		messages,
+	},
+};
diff --git a/test/prefer-set-size.mjs b/test/prefer-set-size.mjs
new file mode 100644
index 0000000000..5cf306d58a
--- /dev/null
+++ b/test/prefer-set-size.mjs
@@ -0,0 +1,25 @@
+import outdent from 'outdent';
+import {getTester} from './utils/test.mjs';
+
+const {test} = getTester(import.meta);
+
+test.snapshot({
+	valid: [
+		// 'new Set(foo).size',
+		// 'for (const foo of bar) console.log([...foo].length)',
+		// '[...new Set(array), foo].length',
+		// '[foo, ...new Set(array), ].length',
+		// '[...new Set(array)].notLength',
+		// '[...new Set(array)].length()',
+		// '[...new Set(array)]?.length',
+		// '[...new Set(array)][length]',
+		// '[...new Set(array)]["length"]',
+	],
+	invalid: [
+		'[...new Set(array)].length',
+		// outdent`
+		// 	const foo = new Set([]);
+		// 	console.log([...foo].length);
+		// `,
+	],
+});
diff --git a/test/snapshots/prefer-set-size.mjs.md b/test/snapshots/prefer-set-size.mjs.md
new file mode 100644
index 0000000000..bb34915d88
--- /dev/null
+++ b/test/snapshots/prefer-set-size.mjs.md
@@ -0,0 +1,21 @@
+# Snapshot report for `test/prefer-set-size.mjs`
+
+The actual snapshot is saved in `prefer-set-size.mjs.snap`.
+
+Generated by [AVA](https://avajs.dev).
+
+## Invalid #1
+      1 | [...new Set(array)].length
+
+> Output
+
+    `␊
+      1 | new Set(array).size␊
+    `
+
+> Error 1/1
+
+    `␊
+    > 1 | [...new Set(array)].length␊
+        |                     ^^^^^^ Prefer use \`Set#size\`.␊
+    `
diff --git a/test/snapshots/prefer-set-size.mjs.snap b/test/snapshots/prefer-set-size.mjs.snap
new file mode 100644
index 0000000000000000000000000000000000000000..b89b3f66ca9b3cca6036711527618e838404f293
GIT binary patch
literal 175
zcmV;g08sxyRzV<BZeeh9Xm4~Nb}|YA00<UCunqLYwWx0+EgIo$(I1Nl00000000Bi
zU|?WiWcXR|`0(|q#+kbotp8nV>FmP900Np&JQ0YQ8Q8&MjI0cTjM7{R3Wf?b3VEsJ
z3c;x*8i_?kiItjq#hF#9Tqp{oxa`0RqxJOkP!-4O<)r4Nmt+7<QUEHz2I9a#A)qKV
dEwxCYv^Z5E0jOUYWJ`h`7XY|svRk<T000+!N)7-3

literal 0
HcmV?d00001


From ec23e04cf09c3f57305bc9901ebd5ebec42f2cf1 Mon Sep 17 00:00:00 2001
From: fisker Cheung <lionkay@gmail.com>
Date: Mon, 7 Nov 2022 17:18:26 +0800
Subject: [PATCH 02/12] Variable

---
 rules/prefer-set-size.js                |  19 +++++++++++++++++--
 test/prefer-set-size.mjs                |   8 ++++----
 test/snapshots/prefer-set-size.mjs.md   |  19 +++++++++++++++++++
 test/snapshots/prefer-set-size.mjs.snap | Bin 175 -> 263 bytes
 4 files changed, 40 insertions(+), 6 deletions(-)

diff --git a/rules/prefer-set-size.js b/rules/prefer-set-size.js
index 85a278cb5f..ba33f3d66a 100644
--- a/rules/prefer-set-size.js
+++ b/rules/prefer-set-size.js
@@ -19,7 +19,7 @@ const lengthAccessSelector = [
 ].join('');
 
 const isNewSet = node =>
-	node.type === 'NewExpression'
+	node?.type === 'NewExpression'
 	&& node.callee.type === 'Identifier'
 	&& node.callee.name === 'Set';
 
@@ -33,7 +33,22 @@ function isSet(node, scope) {
 		return false;
 	}
 
-	const variable = findVariable(scope, maybeSet);
+	const variable = findVariable(scope, node);
+
+	if (!variable || variable.defs.length !== 1) {
+		return false;
+	}
+
+	const [definition] = variable.defs;
+
+	if (definition.type !== 'Variable' || definition.kind !== 'const') {
+		return false;
+	}
+
+	const declarator = definition.node;
+	return declarator.type === 'VariableDeclarator'
+		&& declarator.id.type === 'Identifier'
+		&& isNewSet(definition.node.init)
 }
 
 
diff --git a/test/prefer-set-size.mjs b/test/prefer-set-size.mjs
index 5cf306d58a..fab46823d5 100644
--- a/test/prefer-set-size.mjs
+++ b/test/prefer-set-size.mjs
@@ -17,9 +17,9 @@ test.snapshot({
 	],
 	invalid: [
 		'[...new Set(array)].length',
-		// outdent`
-		// 	const foo = new Set([]);
-		// 	console.log([...foo].length);
-		// `,
+		outdent`
+			const foo = new Set([]);
+			console.log([...foo].length);
+		`,
 	],
 });
diff --git a/test/snapshots/prefer-set-size.mjs.md b/test/snapshots/prefer-set-size.mjs.md
index bb34915d88..298a7d362e 100644
--- a/test/snapshots/prefer-set-size.mjs.md
+++ b/test/snapshots/prefer-set-size.mjs.md
@@ -19,3 +19,22 @@ Generated by [AVA](https://avajs.dev).
     > 1 | [...new Set(array)].length␊
         |                     ^^^^^^ Prefer use \`Set#size\`.␊
     `
+
+## Invalid #2
+      1 | const foo = new Set([]);
+      2 | console.log([...foo].length);
+
+> Output
+
+    `␊
+      1 | const foo = new Set([]);␊
+      2 | console.log(foo.size);␊
+    `
+
+> Error 1/1
+
+    `␊
+      1 | const foo = new Set([]);␊
+    > 2 | console.log([...foo].length);␊
+        |                      ^^^^^^ Prefer use \`Set#size\`.␊
+    `
diff --git a/test/snapshots/prefer-set-size.mjs.snap b/test/snapshots/prefer-set-size.mjs.snap
index b89b3f66ca9b3cca6036711527618e838404f293..8183f2ea3c6ba55df9e78847c7510a61b128a50b 100644
GIT binary patch
literal 263
zcmV+i0r>twRzV<BZeeh9Xm4~Nb}|YA09gxWxL-dVf~>asfLqa5cOQ!g00000000B?
zVqjokV)$^J?L*)J&24LP*u(`Knw6LsK)@S{uL1GTg2#uiPc_cmwP5}4QcGtSCa~y#
zC{AZ&U|?oo2kT;FWe{Yv<x)^ERH#u%&d)0@QAo?rSFlycOD$IjPA$=hj@7gVN*h6?
z^K(-5a`MwPfQs~rGpka8k|;*i5;DpT!>DLIJw2epSiPLoy!4U`uyqPRHCRC$7$^i3
zrKY78DU=qcDkK1nRt7mGK@Zg_(om<stWPW|O03ibyBbwt6wpy1g&>EZDu%fUkBjg-
N2mn;7>mRWJ008f6ZM*;g

literal 175
zcmV;g08sxyRzV<BZeeh9Xm4~Nb}|YA00<UCunqLYwWx0+EgIo$(I1Nl00000000Bi
zU|?WiWcXR|`0(|q#+kbotp8nV>FmP900Np&JQ0YQ8Q8&MjI0cTjM7{R3Wf?b3VEsJ
z3c;x*8i_?kiItjq#hF#9Tqp{oxa`0RqxJOkP!-4O<)r4Nmt+7<QUEHz2I9a#A)qKV
dEwxCYv^Z5E0jOUYWJ`h`7XY|svRk<T000+!N)7-3


From 62adff03c62826a3a90092e5a37eb1b3f1bdaa90 Mon Sep 17 00:00:00 2001
From: fisker Cheung <lionkay@gmail.com>
Date: Mon, 7 Nov 2022 17:19:36 +0800
Subject: [PATCH 03/12] Valid tests

---
 test/prefer-set-size.mjs | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/test/prefer-set-size.mjs b/test/prefer-set-size.mjs
index fab46823d5..16bce6e40c 100644
--- a/test/prefer-set-size.mjs
+++ b/test/prefer-set-size.mjs
@@ -5,15 +5,16 @@ const {test} = getTester(import.meta);
 
 test.snapshot({
 	valid: [
-		// 'new Set(foo).size',
-		// 'for (const foo of bar) console.log([...foo].length)',
-		// '[...new Set(array), foo].length',
-		// '[foo, ...new Set(array), ].length',
-		// '[...new Set(array)].notLength',
-		// '[...new Set(array)].length()',
-		// '[...new Set(array)]?.length',
-		// '[...new Set(array)][length]',
-		// '[...new Set(array)]["length"]',
+		'new Set(foo).size',
+		'for (const foo of bar) console.log([...foo].length)',
+		'[...new Set(array), foo].length',
+		'[foo, ...new Set(array), ].length',
+		'[...new Set(array)].notLength',
+		'[...new Set(array)]?.length',
+		'[...new Set(array)][length]',
+		'[...new Set(array)]["length"]',
+		'[...new NotSet(array)].length',
+		'[...Set(array)].length',
 	],
 	invalid: [
 		'[...new Set(array)].length',

From e0862b35033a72a23ef8fb7a1ecaa564e5d5748a Mon Sep 17 00:00:00 2001
From: fisker Cheung <lionkay@gmail.com>
Date: Mon, 7 Nov 2022 17:21:04 +0800
Subject: [PATCH 04/12] More valid test

---
 test/prefer-set-size.mjs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/test/prefer-set-size.mjs b/test/prefer-set-size.mjs
index 16bce6e40c..5afd7a0e7e 100644
--- a/test/prefer-set-size.mjs
+++ b/test/prefer-set-size.mjs
@@ -15,6 +15,9 @@ test.snapshot({
 		'[...new Set(array)]["length"]',
 		'[...new NotSet(array)].length',
 		'[...Set(array)].length',
+		'const foo = new NotSet([]);[...foo].length;',
+		'const {foo} = new Set([]);[...foo].length;',
+		'const [foo] = new Set([]);[...foo].length;',
 	],
 	invalid: [
 		'[...new Set(array)].length',

From ab8c75942be5d8fd4d0aba6043b80f39a06f5760 Mon Sep 17 00:00:00 2001
From: fisker Cheung <lionkay@gmail.com>
Date: Mon, 7 Nov 2022 17:26:24 +0800
Subject: [PATCH 05/12] Edge case

---
 rules/prefer-set-size.js                |   3 ++-
 test/prefer-set-size.mjs                |   5 +++++
 test/snapshots/prefer-set-size.mjs.md   |  22 ++++++++++++++++++++++
 test/snapshots/prefer-set-size.mjs.snap | Bin 263 -> 368 bytes
 4 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/rules/prefer-set-size.js b/rules/prefer-set-size.js
index ba33f3d66a..b9a6444edb 100644
--- a/rules/prefer-set-size.js
+++ b/rules/prefer-set-size.js
@@ -3,7 +3,7 @@ const {
 	memberExpressionSelector,
 	newExpressionSelector,
 } = require('./selectors/index.js');
-const {} = require('./fix/index.js');
+const { fixSpaceAroundKeyword } = require('./fix/index.js');
 const { findVariable } = require('eslint-utils');
 
 const MESSAGE_ID = 'prefer-set-size';
@@ -64,6 +64,7 @@ function fix(sourceCode, lengthAccessNodes) {
 	return function * (fixer) {
 		yield fixer.replaceText(property, 'size');
 		yield fixer.replaceText(arrayExpression, sourceCode.getText(set));
+		yield * fixSpaceAroundKeyword(fixer, lengthAccessNodes, sourceCode)
 	}
 }
 
diff --git a/test/prefer-set-size.mjs b/test/prefer-set-size.mjs
index 5afd7a0e7e..adbdbb5ad4 100644
--- a/test/prefer-set-size.mjs
+++ b/test/prefer-set-size.mjs
@@ -25,5 +25,10 @@ test.snapshot({
 			const foo = new Set([]);
 			console.log([...foo].length);
 		`,
+		outdent`
+			function isUnique(array) {
+				return[...new Set(array)].length === array.length
+			}
+		`,
 	],
 });
diff --git a/test/snapshots/prefer-set-size.mjs.md b/test/snapshots/prefer-set-size.mjs.md
index 298a7d362e..b2ab835c61 100644
--- a/test/snapshots/prefer-set-size.mjs.md
+++ b/test/snapshots/prefer-set-size.mjs.md
@@ -38,3 +38,25 @@ Generated by [AVA](https://avajs.dev).
     > 2 | console.log([...foo].length);␊
         |                      ^^^^^^ Prefer use \`Set#size\`.␊
     `
+
+## Invalid #3
+      1 | function isUnique(array) {
+      2 | 	return[...new Set(array)].length === array.length
+      3 | }
+
+> Output
+
+    `␊
+      1 | function isUnique(array) {␊
+      2 | 	return new Set(array).size === array.length␊
+      3 | }␊
+    `
+
+> Error 1/1
+
+    `␊
+      1 | function isUnique(array) {␊
+    > 2 | 	return[...new Set(array)].length === array.length␊
+        | 	                          ^^^^^^ Prefer use \`Set#size\`.␊
+      3 | }␊
+    `
diff --git a/test/snapshots/prefer-set-size.mjs.snap b/test/snapshots/prefer-set-size.mjs.snap
index 8183f2ea3c6ba55df9e78847c7510a61b128a50b..cf4d0a4bb632a7c89136dcac7586e27096c6e180 100644
GIT binary patch
literal 368
zcmV-$0gwJcRzV<BZeeh9Xm4~Nb}|YA04vK<#J2F4@L3d@RJtziRUeB800000000Ba
zVPIfjX0X)l`B&%W?Y8ZB+vltt;b%+?Adn5kGK>riAC9wq2t1&<ZA}iFxPU{m5))W7
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OI|u;c)hcrD0ssIm*P`(N

literal 263
zcmV+i0r>twRzV<BZeeh9Xm4~Nb}|YA09gxWxL-dVf~>asfLqa5cOQ!g00000000B?
zVqjokV)$^J?L*)J&24LP*u(`Knw6LsK)@S{uL1GTg2#uiPc_cmwP5}4QcGtSCa~y#
zC{AZ&U|?oo2kT;FWe{Yv<x)^ERH#u%&d)0@QAo?rSFlycOD$IjPA$=hj@7gVN*h6?
z^K(-5a`MwPfQs~rGpka8k|;*i5;DpT!>DLIJw2epSiPLoy!4U`uyqPRHCRC$7$^i3
zrKY78DU=qcDkK1nRt7mGK@Zg_(om<stWPW|O03ibyBbwt6wpy1g&>EZDu%fUkBjg-
N2mn;7>mRWJ008f6ZM*;g


From bcf7dafd8a14c865f9a6aef590fe5f00112373fa Mon Sep 17 00:00:00 2001
From: fisker Cheung <lionkay@gmail.com>
Date: Mon, 7 Nov 2022 17:34:47 +0800
Subject: [PATCH 06/12] Keep comments

---
 rules/prefer-set-size.js                |   5 +-
 test/prefer-set-size.mjs                |  10 +++
 test/snapshots/prefer-set-size.mjs.md   |  93 ++++++++++++++++++++++++
 test/snapshots/prefer-set-size.mjs.snap | Bin 368 -> 640 bytes
 4 files changed, 107 insertions(+), 1 deletion(-)

diff --git a/rules/prefer-set-size.js b/rules/prefer-set-size.js
index b9a6444edb..97b745c222 100644
--- a/rules/prefer-set-size.js
+++ b/rules/prefer-set-size.js
@@ -60,6 +60,10 @@ function fix(sourceCode, lengthAccessNodes) {
 	} = lengthAccessNodes;
 	const set = arrayExpression.elements[0].argument;
 
+	if (sourceCode.getCommentsInside(arrayExpression).length > sourceCode.getCommentsInside(set).length) {
+		return;
+	}
+
 	/** @param {import('eslint').Rule.RuleFixer} fixer */
 	return function * (fixer) {
 		yield fixer.replaceText(property, 'size');
@@ -97,7 +101,6 @@ module.exports = {
 			description: 'Prefer use `Set#size` instead of `Array#length`.',
 		},
 		fixable: 'code',
-
 		messages,
 	},
 };
diff --git a/test/prefer-set-size.mjs b/test/prefer-set-size.mjs
index adbdbb5ad4..3d2f7e3e98 100644
--- a/test/prefer-set-size.mjs
+++ b/test/prefer-set-size.mjs
@@ -16,6 +16,7 @@ test.snapshot({
 		'[...new NotSet(array)].length',
 		'[...Set(array)].length',
 		'const foo = new NotSet([]);[...foo].length;',
+		'let foo = new Set([]);[...foo].length;',
 		'const {foo} = new Set([]);[...foo].length;',
 		'const [foo] = new Set([]);[...foo].length;',
 	],
@@ -30,5 +31,14 @@ test.snapshot({
 				return[...new Set(array)].length === array.length
 			}
 		`,
+		'[...new Set(array),].length',
+		'[...(( new Set(array) ))].length',
+		'(( [...new Set(array)] )).length',
+		outdent`
+			foo
+			;[...new Set(array)].length
+		`,
+		'[/* comment */...new Set(array)].length',
+		'[...new /* comment */ Set(array)].length',
 	],
 });
diff --git a/test/snapshots/prefer-set-size.mjs.md b/test/snapshots/prefer-set-size.mjs.md
index b2ab835c61..bccbbc7820 100644
--- a/test/snapshots/prefer-set-size.mjs.md
+++ b/test/snapshots/prefer-set-size.mjs.md
@@ -60,3 +60,96 @@ Generated by [AVA](https://avajs.dev).
         | 	                          ^^^^^^ Prefer use \`Set#size\`.␊
       3 | }␊
     `
+
+## Invalid #4
+      1 | [...new Set(array),].length
+
+> Output
+
+    `␊
+      1 | new Set(array).size␊
+    `
+
+> Error 1/1
+
+    `␊
+    > 1 | [...new Set(array),].length␊
+        |                      ^^^^^^ Prefer use \`Set#size\`.␊
+    `
+
+## Invalid #5
+      1 | [...(( new Set(array) ))].length
+
+> Output
+
+    `␊
+      1 | new Set(array).size␊
+    `
+
+> Error 1/1
+
+    `␊
+    > 1 | [...(( new Set(array) ))].length␊
+        |                           ^^^^^^ Prefer use \`Set#size\`.␊
+    `
+
+## Invalid #6
+      1 | (( [...new Set(array)] )).length
+
+> Output
+
+    `␊
+      1 | (( new Set(array) )).size␊
+    `
+
+> Error 1/1
+
+    `␊
+    > 1 | (( [...new Set(array)] )).length␊
+        |                           ^^^^^^ Prefer use \`Set#size\`.␊
+    `
+
+## Invalid #7
+      1 | foo
+      2 | ;[...new Set(array)].length
+
+> Output
+
+    `␊
+      1 | foo␊
+      2 | ;new Set(array).size␊
+    `
+
+> Error 1/1
+
+    `␊
+      1 | foo␊
+    > 2 | ;[...new Set(array)].length␊
+        |                      ^^^^^^ Prefer use \`Set#size\`.␊
+    `
+
+## Invalid #8
+      1 | [/* comment */...new Set(array)].length
+
+> Error 1/1
+
+    `␊
+    > 1 | [/* comment */...new Set(array)].length␊
+        |                                  ^^^^^^ Prefer use \`Set#size\`.␊
+    `
+
+## Invalid #9
+      1 | [...new /* comment */ Set(array)].length
+
+> Output
+
+    `␊
+      1 | new /* comment */ Set(array).size␊
+    `
+
+> Error 1/1
+
+    `␊
+    > 1 | [...new /* comment */ Set(array)].length␊
+        |                                   ^^^^^^ Prefer use \`Set#size\`.␊
+    `
diff --git a/test/snapshots/prefer-set-size.mjs.snap b/test/snapshots/prefer-set-size.mjs.snap
index cf4d0a4bb632a7c89136dcac7586e27096c6e180..07b840cea5b9698704e162f46a5f675c08817a46 100644
GIT binary patch
literal 640
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zU}Rw6WRQRI&{gxw->rUPfi}_%A%#FeAZP+&^-rA}826vN$mx2helEN0KPIr~PAIko
zDm2Q<?C`b|nV~k1Z*3D})N>}VXbu!V0Afqso_}?2-fr8Dw|&ma5q`!57WHO=;6FgT
zlkM}_1tuvU<o1|5ZPUDL!UPsIV20o&K)g#PY`$r^N=tO1`~D|8%q}v4MbAR9BMSq=
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auyu4z1yMKynuu`5?;rph%|~@>2LJ#xs2`F5

literal 368
zcmV-$0gwJcRzV<BZeeh9Xm4~Nb}|YA04vK<#J2F4@L3d@RJtziRUeB800000000Ba
zVPIfjX0X)l`B&%W?Y8ZB+vltt;b%+?Adn5kGK>riAC9wq2t1&<ZA}iFxPU{m5))W7
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zx&}}YI7on!C`Q#1GRh9aD3I@g3SnLbTL<zZ8NNetiZs+ISRxWtVHD6&AceT20gsFD
OI|u;c)hcrD0ssIm*P`(N


From 77fbc7eeac3239140244b9f79f48955569722832 Mon Sep 17 00:00:00 2001
From: fisker Cheung <lionkay@gmail.com>
Date: Mon, 7 Nov 2022 17:42:29 +0800
Subject: [PATCH 07/12] Docs

---
 docs/rules/prefer-set-size.md | 10 +++++++---
 rules/prefer-set-size.js      | 11 ++++-------
 2 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/docs/rules/prefer-set-size.md b/docs/rules/prefer-set-size.md
index 70070de78b..d1174e28ca 100644
--- a/docs/rules/prefer-set-size.md
+++ b/docs/rules/prefer-set-size.md
@@ -1,16 +1,20 @@
 <!-- end auto-generated rule header -->
 <!-- Do not manually modify this header. Run: `npm run fix:eslint-docs` -->
 
-<!-- Remove this comment, add more detailed description. -->
+Prefer use `Set#size` directly instead of convert it to an array, and use `.length` of the array.
 
 ## Fail
 
 ```js
-const foo = 'unicorn';
+function isUnique(array) {
+	return [...new Set(array)].length === array.length;
+}
 ```
 
 ## Pass
 
 ```js
-const foo = '🦄';
+function isUnique(array) {
+	return new Set(array).size === array.length;
+}
 ```
diff --git a/rules/prefer-set-size.js b/rules/prefer-set-size.js
index 97b745c222..7d4a5a6010 100644
--- a/rules/prefer-set-size.js
+++ b/rules/prefer-set-size.js
@@ -1,14 +1,11 @@
 'use strict';
-const {
-	memberExpressionSelector,
-	newExpressionSelector,
-} = require('./selectors/index.js');
-const { fixSpaceAroundKeyword } = require('./fix/index.js');
 const { findVariable } = require('eslint-utils');
+const {memberExpressionSelector} = require('./selectors/index.js');
+const { fixSpaceAroundKeyword } = require('./fix/index.js');
 
 const MESSAGE_ID = 'prefer-set-size';
 const messages = {
-	[MESSAGE_ID]: 'Prefer use `Set#size`.'
+	[MESSAGE_ID]: 'Prefer use `Set#size` instead of `Array#length`.'
 }
 
 const lengthAccessSelector = [
@@ -98,7 +95,7 @@ module.exports = {
 	meta: {
 		type: 'suggestion',
 		docs: {
-			description: 'Prefer use `Set#size` instead of `Array#length`.',
+			description: 'Prefer use `Set#size` instead of convert it to Array first.',
 		},
 		fixable: 'code',
 		messages,

From 0be530b8c193331bd00fc5d447f7be51c7449b2f Mon Sep 17 00:00:00 2001
From: fisker Cheung <lionkay@gmail.com>
Date: Mon, 7 Nov 2022 18:53:14 +0800
Subject: [PATCH 08/12] Linting

---
 docs/rules/prefer-set-size.md |  6 ++++++
 readme.md                     |  1 +
 rules/prefer-set-size.js      | 22 ++++++++++------------
 3 files changed, 17 insertions(+), 12 deletions(-)

diff --git a/docs/rules/prefer-set-size.md b/docs/rules/prefer-set-size.md
index d1174e28ca..00f082fd92 100644
--- a/docs/rules/prefer-set-size.md
+++ b/docs/rules/prefer-set-size.md
@@ -1,3 +1,9 @@
+# Prefer use `Set#size` instead of convert it to Array first
+
+✅ This rule is enabled in the `recommended` [config](https://github.com/sindresorhus/eslint-plugin-unicorn#preset-configs).
+
+🔧 This rule is automatically fixable by the [`--fix` CLI option](https://eslint.org/docs/latest/user-guide/command-line-interface#--fix).
+
 <!-- end auto-generated rule header -->
 <!-- Do not manually modify this header. Run: `npm run fix:eslint-docs` -->
 
diff --git a/readme.md b/readme.md
index faa635af74..acef8d442d 100644
--- a/readme.md
+++ b/readme.md
@@ -139,6 +139,7 @@ Use a [preset config](#preset-configs) or configure each rules in `package.json`
 | [prefer-reflect-apply](docs/rules/prefer-reflect-apply.md)                                       | Prefer `Reflect.apply()` over `Function#apply()`.                                                                                                                                                                 | ✅  | 🔧 |    |
 | [prefer-regexp-test](docs/rules/prefer-regexp-test.md)                                           | Prefer `RegExp#test()` over `String#match()` and `RegExp#exec()`.                                                                                                                                                 | ✅  | 🔧 |    |
 | [prefer-set-has](docs/rules/prefer-set-has.md)                                                   | Prefer `Set#has()` over `Array#includes()` when checking for existence or non-existence.                                                                                                                          | ✅  | 🔧 | 💡 |
+| [prefer-set-size](docs/rules/prefer-set-size.md)                                                 | Prefer use `Set#size` instead of convert it to Array first.                                                                                                                                                       | ✅  | 🔧 |    |
 | [prefer-spread](docs/rules/prefer-spread.md)                                                     | Prefer the spread operator over `Array.from(…)`, `Array#concat(…)`, `Array#slice()` and `String#split('')`.                                                                                                       | ✅  | 🔧 | 💡 |
 | [prefer-string-replace-all](docs/rules/prefer-string-replace-all.md)                             | Prefer `String#replaceAll()` over regex searches with the global flag.                                                                                                                                            |    | 🔧 |    |
 | [prefer-string-slice](docs/rules/prefer-string-slice.md)                                         | Prefer `String#slice()` over `String#substr()` and `String#substring()`.                                                                                                                                          | ✅  | 🔧 |    |
diff --git a/rules/prefer-set-size.js b/rules/prefer-set-size.js
index 7d4a5a6010..214321f210 100644
--- a/rules/prefer-set-size.js
+++ b/rules/prefer-set-size.js
@@ -1,12 +1,12 @@
 'use strict';
-const { findVariable } = require('eslint-utils');
+const {findVariable} = require('eslint-utils');
 const {memberExpressionSelector} = require('./selectors/index.js');
-const { fixSpaceAroundKeyword } = require('./fix/index.js');
+const {fixSpaceAroundKeyword} = require('./fix/index.js');
 
 const MESSAGE_ID = 'prefer-set-size';
 const messages = {
-	[MESSAGE_ID]: 'Prefer use `Set#size` instead of `Array#length`.'
-}
+	[MESSAGE_ID]: 'Prefer use `Set#size` instead of `Array#length`.',
+};
 
 const lengthAccessSelector = [
 	memberExpressionSelector('length'),
@@ -25,7 +25,6 @@ function isSet(node, scope) {
 		return true;
 	}
 
-
 	if (node.type !== 'Identifier') {
 		return false;
 	}
@@ -45,15 +44,14 @@ function isSet(node, scope) {
 	const declarator = definition.node;
 	return declarator.type === 'VariableDeclarator'
 		&& declarator.id.type === 'Identifier'
-		&& isNewSet(definition.node.init)
+		&& isNewSet(definition.node.init);
 }
 
-
 // `[...set].length` -> `set.size`
 function fix(sourceCode, lengthAccessNodes) {
 	const {
 		object: arrayExpression,
-		property
+		property,
 	} = lengthAccessNodes;
 	const set = arrayExpression.elements[0].argument;
 
@@ -65,8 +63,8 @@ function fix(sourceCode, lengthAccessNodes) {
 	return function * (fixer) {
 		yield fixer.replaceText(property, 'size');
 		yield fixer.replaceText(arrayExpression, sourceCode.getText(set));
-		yield * fixSpaceAroundKeyword(fixer, lengthAccessNodes, sourceCode)
-	}
+		yield * fixSpaceAroundKeyword(fixer, lengthAccessNodes, sourceCode);
+	};
 }
 
 /** @param {import('eslint').Rule.RuleContext} context */
@@ -84,8 +82,8 @@ const create = context => {
 				node: node.property,
 				messageId: MESSAGE_ID,
 				fix: fix(sourceCode, node),
-			}
-		}
+			};
+		},
 	};
 };
 

From f99a2031b7e84ea0c722cbbdeca7c7195774a834 Mon Sep 17 00:00:00 2001
From: fisker Cheung <lionkay@gmail.com>
Date: Mon, 7 Nov 2022 19:04:53 +0800
Subject: [PATCH 09/12] Fix snapshots

---
 test/snapshots/prefer-set-size.mjs.md   |  18 +++++++++---------
 test/snapshots/prefer-set-size.mjs.snap | Bin 640 -> 668 bytes
 2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/test/snapshots/prefer-set-size.mjs.md b/test/snapshots/prefer-set-size.mjs.md
index bccbbc7820..72b1c65d28 100644
--- a/test/snapshots/prefer-set-size.mjs.md
+++ b/test/snapshots/prefer-set-size.mjs.md
@@ -17,7 +17,7 @@ Generated by [AVA](https://avajs.dev).
 
     `␊
     > 1 | [...new Set(array)].length␊
-        |                     ^^^^^^ Prefer use \`Set#size\`.␊
+        |                     ^^^^^^ Prefer use \`Set#size\` instead of \`Array#length\`.␊
     `
 
 ## Invalid #2
@@ -36,7 +36,7 @@ Generated by [AVA](https://avajs.dev).
     `␊
       1 | const foo = new Set([]);␊
     > 2 | console.log([...foo].length);␊
-        |                      ^^^^^^ Prefer use \`Set#size\`.␊
+        |                      ^^^^^^ Prefer use \`Set#size\` instead of \`Array#length\`.␊
     `
 
 ## Invalid #3
@@ -57,7 +57,7 @@ Generated by [AVA](https://avajs.dev).
     `␊
       1 | function isUnique(array) {␊
     > 2 | 	return[...new Set(array)].length === array.length␊
-        | 	                          ^^^^^^ Prefer use \`Set#size\`.␊
+        | 	                          ^^^^^^ Prefer use \`Set#size\` instead of \`Array#length\`.␊
       3 | }␊
     `
 
@@ -74,7 +74,7 @@ Generated by [AVA](https://avajs.dev).
 
     `␊
     > 1 | [...new Set(array),].length␊
-        |                      ^^^^^^ Prefer use \`Set#size\`.␊
+        |                      ^^^^^^ Prefer use \`Set#size\` instead of \`Array#length\`.␊
     `
 
 ## Invalid #5
@@ -90,7 +90,7 @@ Generated by [AVA](https://avajs.dev).
 
     `␊
     > 1 | [...(( new Set(array) ))].length␊
-        |                           ^^^^^^ Prefer use \`Set#size\`.␊
+        |                           ^^^^^^ Prefer use \`Set#size\` instead of \`Array#length\`.␊
     `
 
 ## Invalid #6
@@ -106,7 +106,7 @@ Generated by [AVA](https://avajs.dev).
 
     `␊
     > 1 | (( [...new Set(array)] )).length␊
-        |                           ^^^^^^ Prefer use \`Set#size\`.␊
+        |                           ^^^^^^ Prefer use \`Set#size\` instead of \`Array#length\`.␊
     `
 
 ## Invalid #7
@@ -125,7 +125,7 @@ Generated by [AVA](https://avajs.dev).
     `␊
       1 | foo␊
     > 2 | ;[...new Set(array)].length␊
-        |                      ^^^^^^ Prefer use \`Set#size\`.␊
+        |                      ^^^^^^ Prefer use \`Set#size\` instead of \`Array#length\`.␊
     `
 
 ## Invalid #8
@@ -135,7 +135,7 @@ Generated by [AVA](https://avajs.dev).
 
     `␊
     > 1 | [/* comment */...new Set(array)].length␊
-        |                                  ^^^^^^ Prefer use \`Set#size\`.␊
+        |                                  ^^^^^^ Prefer use \`Set#size\` instead of \`Array#length\`.␊
     `
 
 ## Invalid #9
@@ -151,5 +151,5 @@ Generated by [AVA](https://avajs.dev).
 
     `␊
     > 1 | [...new /* comment */ Set(array)].length␊
-        |                                   ^^^^^^ Prefer use \`Set#size\`.␊
+        |                                   ^^^^^^ Prefer use \`Set#size\` instead of \`Array#length\`.␊
     `
diff --git a/test/snapshots/prefer-set-size.mjs.snap b/test/snapshots/prefer-set-size.mjs.snap
index 07b840cea5b9698704e162f46a5f675c08817a46..210745af4bb9c1ca998247142547ea9745730883 100644
GIT binary patch
delta 645
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zU}j(khYceugCJ8M1DBnGp+b#9w7!-?a(-@ZYF>$gmcE{zUS4XsLU3w{Mt@>aQDUWL
ztX@uPUV2FemjV#fC=dj3V4x6Cl$w@Wq)=L%s*nIQOu0C-Dm6hNGq1QLH8DjYKTRRQ
z5oEkF#P9??E@a0sY65KoxeeqL6z3s1Ob=uviZ-SRa6du4flDu`o}!Mg6rsM-&`>}P
zV+BoYzG;B@2B<z7GhRTNh=242Ra_qnb$wcCUUErhex5>RacEv<VQDJN6V*TkMnDCe
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z=9Bz<Xz*BL2^WlrM`(ih(;BxA@x?w>B3>FPGZJz)BKu)W<V0sXx>~xMu?(%$Kq%Is
zTOiv)9h;mF)BuWj1zWhoqhmF#p@|11ou8Acmy@5a0aOI`3{Vm!8m2Q4GRqFbERffM
f3Sr&_+c!8;6=Mm`*dZcv$aN|Jr@9WbTL=IE&Y~EC

delta 617
zcmV-v0+#)p1%L%2K~_N^Q*L2!b7*gLAa*he0szGeV^w1K5izkC7U<92`#6yzB!6fE
zV)aj*8yNSWyvXT#sD3WH>^~;3=uRlM1u8Vk%IxsA6Pcklk8f=gW7KmduxJhxKLBD&
z-JXASZr*O&j<<cz$`O9X1QzvXg5W<uyp!$o*##ykALRC!J8jdvY{CQ<HDHF|B|yAO
zCTzZGxk^iPq5J+PJIpRJfkn?kv40~A1H&U7$*c1?%_9ZwE&b9t$)%nNESd$ySAh7#
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zNzF?y$>34|f*J*aAPx)^0*X@8Qi~Kyi&GU6fQBg-XI7;q=y9RAKoe*t$ORw^Q5=C}
zy&gy-s<twi!=Y})rIl2dlj3wmsM9qx6i|apK@*#k)1XcUDv!ntVUQjool1feW1&t=
zE6qzT$;{7F$Se-c%PcHSg@3uU8mPbssDQI5wWPEt56vTBUntnx+A4tg2nQMiwbY_m
z#k7cluw8b@c3}wws0G+;1O*8vxnY9M!HjA!_vYtA1Hl@L@6qEBp$Fm_Yuw(z7m*~y
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z&q>wG$xqh+DgrwhD2ZZJEg_@qFpL8E52z64C$M#NO$AXn1Dc3%#_u2i8_h>`YX<-T
DOFtHH


From 4cd7578e12360a9f20d9e9adfcf75f14fcee5dd3 Mon Sep 17 00:00:00 2001
From: fisker Cheung <lionkay@gmail.com>
Date: Mon, 7 Nov 2022 19:53:06 +0800
Subject: [PATCH 10/12] Imporve coverage

---
 test/prefer-set-size.mjs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/test/prefer-set-size.mjs b/test/prefer-set-size.mjs
index 3d2f7e3e98..c533cad911 100644
--- a/test/prefer-set-size.mjs
+++ b/test/prefer-set-size.mjs
@@ -19,6 +19,8 @@ test.snapshot({
 		'let foo = new Set([]);[...foo].length;',
 		'const {foo} = new Set([]);[...foo].length;',
 		'const [foo] = new Set([]);[...foo].length;',
+		'[...foo].length',
+		'var foo = new Set(); var foo = new Set(); [...foo].length',
 	],
 	invalid: [
 		'[...new Set(array)].length',

From 0a292a4855844ebfab08cda64d48ba1ea92a7390 Mon Sep 17 00:00:00 2001
From: fisker Cheung <lionkay@gmail.com>
Date: Tue, 15 Nov 2022 18:40:24 +0800
Subject: [PATCH 11/12] Apply suggestions from code review

Co-authored-by: Sindre Sorhus <sindresorhus@gmail.com>
---
 docs/rules/prefer-set-size.md | 4 ++--
 rules/prefer-set-size.js      | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/docs/rules/prefer-set-size.md b/docs/rules/prefer-set-size.md
index 00f082fd92..7ddc30c1d1 100644
--- a/docs/rules/prefer-set-size.md
+++ b/docs/rules/prefer-set-size.md
@@ -1,4 +1,4 @@
-# Prefer use `Set#size` instead of convert it to Array first
+# Prefer using `Set#size` instead of `Array#length`
 
 ✅ This rule is enabled in the `recommended` [config](https://github.com/sindresorhus/eslint-plugin-unicorn#preset-configs).
 
@@ -7,7 +7,7 @@
 <!-- end auto-generated rule header -->
 <!-- Do not manually modify this header. Run: `npm run fix:eslint-docs` -->
 
-Prefer use `Set#size` directly instead of convert it to an array, and use `.length` of the array.
+Prefer using `Set#size` directly instead of first converting it to an array and then using its `.length` property.
 
 ## Fail
 
diff --git a/rules/prefer-set-size.js b/rules/prefer-set-size.js
index 214321f210..1af2c9df63 100644
--- a/rules/prefer-set-size.js
+++ b/rules/prefer-set-size.js
@@ -5,7 +5,7 @@ const {fixSpaceAroundKeyword} = require('./fix/index.js');
 
 const MESSAGE_ID = 'prefer-set-size';
 const messages = {
-	[MESSAGE_ID]: 'Prefer use `Set#size` instead of `Array#length`.',
+	[MESSAGE_ID]: 'Prefer using `Set#size` instead of `Array#length`.',
 };
 
 const lengthAccessSelector = [

From f2b92db3c84484fce8f98feb9f88c049e9aa4938 Mon Sep 17 00:00:00 2001
From: fisker Cheung <lionkay@gmail.com>
Date: Tue, 15 Nov 2022 18:57:05 +0800
Subject: [PATCH 12/12] Fix

---
 readme.md                               |   2 +-
 rules/prefer-set-size.js                |   2 +-
 test/snapshots/prefer-set-size.mjs.md   |  18 +++++++++---------
 test/snapshots/prefer-set-size.mjs.snap | Bin 668 -> 672 bytes
 4 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/readme.md b/readme.md
index acef8d442d..fd32d71970 100644
--- a/readme.md
+++ b/readme.md
@@ -139,7 +139,7 @@ Use a [preset config](#preset-configs) or configure each rules in `package.json`
 | [prefer-reflect-apply](docs/rules/prefer-reflect-apply.md)                                       | Prefer `Reflect.apply()` over `Function#apply()`.                                                                                                                                                                 | ✅  | 🔧 |    |
 | [prefer-regexp-test](docs/rules/prefer-regexp-test.md)                                           | Prefer `RegExp#test()` over `String#match()` and `RegExp#exec()`.                                                                                                                                                 | ✅  | 🔧 |    |
 | [prefer-set-has](docs/rules/prefer-set-has.md)                                                   | Prefer `Set#has()` over `Array#includes()` when checking for existence or non-existence.                                                                                                                          | ✅  | 🔧 | 💡 |
-| [prefer-set-size](docs/rules/prefer-set-size.md)                                                 | Prefer use `Set#size` instead of convert it to Array first.                                                                                                                                                       | ✅  | 🔧 |    |
+| [prefer-set-size](docs/rules/prefer-set-size.md)                                                 | Prefer using `Set#size` instead of `Array#length`.                                                                                                                                                                | ✅  | 🔧 |    |
 | [prefer-spread](docs/rules/prefer-spread.md)                                                     | Prefer the spread operator over `Array.from(…)`, `Array#concat(…)`, `Array#slice()` and `String#split('')`.                                                                                                       | ✅  | 🔧 | 💡 |
 | [prefer-string-replace-all](docs/rules/prefer-string-replace-all.md)                             | Prefer `String#replaceAll()` over regex searches with the global flag.                                                                                                                                            |    | 🔧 |    |
 | [prefer-string-slice](docs/rules/prefer-string-slice.md)                                         | Prefer `String#slice()` over `String#substr()` and `String#substring()`.                                                                                                                                          | ✅  | 🔧 |    |
diff --git a/rules/prefer-set-size.js b/rules/prefer-set-size.js
index 1af2c9df63..c7b7eaf6ec 100644
--- a/rules/prefer-set-size.js
+++ b/rules/prefer-set-size.js
@@ -93,7 +93,7 @@ module.exports = {
 	meta: {
 		type: 'suggestion',
 		docs: {
-			description: 'Prefer use `Set#size` instead of convert it to Array first.',
+			description: 'Prefer using `Set#size` instead of `Array#length`.',
 		},
 		fixable: 'code',
 		messages,
diff --git a/test/snapshots/prefer-set-size.mjs.md b/test/snapshots/prefer-set-size.mjs.md
index 72b1c65d28..99ee5ca8b5 100644
--- a/test/snapshots/prefer-set-size.mjs.md
+++ b/test/snapshots/prefer-set-size.mjs.md
@@ -17,7 +17,7 @@ Generated by [AVA](https://avajs.dev).
 
     `␊
     > 1 | [...new Set(array)].length␊
-        |                     ^^^^^^ Prefer use \`Set#size\` instead of \`Array#length\`.␊
+        |                     ^^^^^^ Prefer using \`Set#size\` instead of \`Array#length\`.␊
     `
 
 ## Invalid #2
@@ -36,7 +36,7 @@ Generated by [AVA](https://avajs.dev).
     `␊
       1 | const foo = new Set([]);␊
     > 2 | console.log([...foo].length);␊
-        |                      ^^^^^^ Prefer use \`Set#size\` instead of \`Array#length\`.␊
+        |                      ^^^^^^ Prefer using \`Set#size\` instead of \`Array#length\`.␊
     `
 
 ## Invalid #3
@@ -57,7 +57,7 @@ Generated by [AVA](https://avajs.dev).
     `␊
       1 | function isUnique(array) {␊
     > 2 | 	return[...new Set(array)].length === array.length␊
-        | 	                          ^^^^^^ Prefer use \`Set#size\` instead of \`Array#length\`.␊
+        | 	                          ^^^^^^ Prefer using \`Set#size\` instead of \`Array#length\`.␊
       3 | }␊
     `
 
@@ -74,7 +74,7 @@ Generated by [AVA](https://avajs.dev).
 
     `␊
     > 1 | [...new Set(array),].length␊
-        |                      ^^^^^^ Prefer use \`Set#size\` instead of \`Array#length\`.␊
+        |                      ^^^^^^ Prefer using \`Set#size\` instead of \`Array#length\`.␊
     `
 
 ## Invalid #5
@@ -90,7 +90,7 @@ Generated by [AVA](https://avajs.dev).
 
     `␊
     > 1 | [...(( new Set(array) ))].length␊
-        |                           ^^^^^^ Prefer use \`Set#size\` instead of \`Array#length\`.␊
+        |                           ^^^^^^ Prefer using \`Set#size\` instead of \`Array#length\`.␊
     `
 
 ## Invalid #6
@@ -106,7 +106,7 @@ Generated by [AVA](https://avajs.dev).
 
     `␊
     > 1 | (( [...new Set(array)] )).length␊
-        |                           ^^^^^^ Prefer use \`Set#size\` instead of \`Array#length\`.␊
+        |                           ^^^^^^ Prefer using \`Set#size\` instead of \`Array#length\`.␊
     `
 
 ## Invalid #7
@@ -125,7 +125,7 @@ Generated by [AVA](https://avajs.dev).
     `␊
       1 | foo␊
     > 2 | ;[...new Set(array)].length␊
-        |                      ^^^^^^ Prefer use \`Set#size\` instead of \`Array#length\`.␊
+        |                      ^^^^^^ Prefer using \`Set#size\` instead of \`Array#length\`.␊
     `
 
 ## Invalid #8
@@ -135,7 +135,7 @@ Generated by [AVA](https://avajs.dev).
 
     `␊
     > 1 | [/* comment */...new Set(array)].length␊
-        |                                  ^^^^^^ Prefer use \`Set#size\` instead of \`Array#length\`.␊
+        |                                  ^^^^^^ Prefer using \`Set#size\` instead of \`Array#length\`.␊
     `
 
 ## Invalid #9
@@ -151,5 +151,5 @@ Generated by [AVA](https://avajs.dev).
 
     `␊
     > 1 | [...new /* comment */ Set(array)].length␊
-        |                                   ^^^^^^ Prefer use \`Set#size\` instead of \`Array#length\`.␊
+        |                                   ^^^^^^ Prefer using \`Set#size\` instead of \`Array#length\`.␊
     `
diff --git a/test/snapshots/prefer-set-size.mjs.snap b/test/snapshots/prefer-set-size.mjs.snap
index 210745af4bb9c1ca998247142547ea9745730883..66a1fea33ec5c76bc56c2eb6f1a2d572c911245a 100644
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