From 73ffb34cbd1d09b64dade61246b7b671cb8bf224 Mon Sep 17 00:00:00 2001
From: uzlopak <aras.abbasi@googlemail.com>
Date: Thu, 14 Sep 2023 02:34:42 +0200
Subject: [PATCH] perf: improve formatList in errors.js

---
 benchmark/error/format-list.js | 29 +++++++++++++++++++++++++++++
 lib/internal/errors.js         |  9 +++++++--
 2 files changed, 36 insertions(+), 2 deletions(-)
 create mode 100644 benchmark/error/format-list.js

diff --git a/benchmark/error/format-list.js b/benchmark/error/format-list.js
new file mode 100644
index 00000000000000..0f57cd9c7cd8e3
--- /dev/null
+++ b/benchmark/error/format-list.js
@@ -0,0 +1,29 @@
+'use strict';
+
+const common = require('../common.js');
+
+const bench = common.createBenchmark(main, {
+  n: [1e7],
+}, {
+  flags: ['--expose-internals'],
+});
+
+const lists = [
+    [],
+    ['a'],
+    ['a', 'b'],
+    ['a', 'b', 'c'],
+  ];
+
+function main({ n }) {
+  const {
+    formatList
+  } = require('internal/errors');
+
+  bench.start();
+  for (let i = 0; i < n; ++i) {
+    for (let j = 0; j < lists.length; ++j)
+    formatList(lists[j]);
+  }
+  bench.end(n);
+}
diff --git a/lib/internal/errors.js b/lib/internal/errors.js
index 28c241f6fedda9..3889e329e531da 100644
--- a/lib/internal/errors.js
+++ b/lib/internal/errors.js
@@ -901,8 +901,13 @@ function determineSpecificType(value) {
  * @returns {string}
  */
 function formatList(array, type = 'and') {
-  return array.length < 3 ? ArrayPrototypeJoin(array, ` ${type} `) :
-    `${ArrayPrototypeJoin(ArrayPrototypeSlice(array, 0, -1), ', ')}, ${type} ${array[array.length - 1]}`;
+  switch (array.length) {
+    case 0: return '';
+    case 1: return array[0];
+    case 2: return `${array[0]} ${type} ${array[1]}`;
+    default:
+      return `${ArrayPrototypeJoin(ArrayPrototypeSlice(array, 0, -1), ', ')}, ${type} ${array[array.length - 1]}`;
+  }
 }
 
 module.exports = {