From caec80e3ae8cad70e3e78fb6d9403fe7cf94912f Mon Sep 17 00:00:00 2001
From: Mert Can Altin <mertgold60@gmail.com>
Date: Sun, 18 Oct 2026 15:15:42 +0300
Subject: [PATCH 1/3] lib: optimize TextEncoder.encode for short strings

Assisted-by: Claude opus 5.5
Signed-off-by: Mert Can Altin <mertgold60@gmail.com>
---
 lib/internal/encoding.js                      | 18 +++++++-
 ...hatwg-encoding-custom-textencoder-short.js | 42 +++++++++++++++++++
 2 files changed, 59 insertions(+), 1 deletion(-)
 create mode 100644 test/parallel/test-whatwg-encoding-custom-textencoder-short.js

diff --git a/lib/internal/encoding.js b/lib/internal/encoding.js
index 11003db8bc51..2ad74d54536d 100644
--- a/lib/internal/encoding.js
+++ b/lib/internal/encoding.js
@@ -13,6 +13,7 @@ const {
   StringPrototypeSlice,
   Symbol,
   SymbolToStringTag,
+  Uint8Array,
 } = primordials;
 
 const { FastBuffer } = require('internal/buffer');
@@ -338,11 +339,26 @@ function getEncodingFromLabel(label) {
 
 let lazyInspect;
 
+const kSmallEncodeLength = 32;
+let smallEncodeScratch;
+
 class TextEncoder {
   #encoding = 'utf-8';
 
   #encode(input) {
-    return encodeUtf8String(`${input}`);
+    input = `${input}`;
+    if (input.length > kSmallEncodeLength) {
+      return encodeUtf8String(input);
+    }
+
+    smallEncodeScratch ??= new Uint8Array(kSmallEncodeLength * 3);
+    encodeInto(input, smallEncodeScratch);
+    const written = encodeIntoResults[1];
+    const result = new Uint8Array(written);
+    for (let i = 0; i < written; i++) {
+      result[i] = smallEncodeScratch[i];
+    }
+    return result;
   }
 
   #encodeInto(input, dest) {
diff --git a/test/parallel/test-whatwg-encoding-custom-textencoder-short.js b/test/parallel/test-whatwg-encoding-custom-textencoder-short.js
new file mode 100644
index 000000000000..136edfed9d99
--- /dev/null
+++ b/test/parallel/test-whatwg-encoding-custom-textencoder-short.js
@@ -0,0 +1,42 @@
+'use strict';
+
+// Tests TextEncoder.prototype.encode() around the short string path.
+
+require('../common');
+
+const assert = require('assert');
+
+const encoder = new TextEncoder();
+
+const inputs = [
+  '',
+  'a',
+  'a'.repeat(32),
+  'a'.repeat(33),
+  '\xff'.repeat(32),
+  'ğ'.repeat(32),
+  'ࠀ'.repeat(32),
+  '\u{1F44B}'.repeat(16),
+  '\u{1F44B}'.repeat(17),
+  '\ud800',
+  'a\udc00b',
+  'abc\ud83d',
+];
+
+for (const input of inputs) {
+  const result = encoder.encode(input);
+  const expected = Buffer.from(input, 'utf8');
+  assert.strictEqual(Object.getPrototypeOf(result), Uint8Array.prototype);
+  assert.strictEqual(result.byteOffset, 0);
+  assert.strictEqual(result.buffer.byteLength, expected.length);
+  assert.deepStrictEqual(Buffer.from(result), expected);
+}
+
+{
+  // Results must not share memory with each other.
+  const first = encoder.encode('first');
+  const second = encoder.encode('second');
+  assert.notStrictEqual(first.buffer, second.buffer);
+  assert.strictEqual(Buffer.from(first).toString(), 'first');
+  assert.strictEqual(Buffer.from(second).toString(), 'second');
+}

From a13f524ba1df1f2c288f3ad5ba3112390c346bff Mon Sep 17 00:00:00 2001
From: Mert Can Altin <mertgold60@gmail.com>
Date: Sun, 18 Oct 2026 16:51:17 +0300
Subject: [PATCH 2/3] Update
 test/parallel/test-whatwg-encoding-custom-textencoder-short.js

Co-authored-by: Antoine du Hamel <duhamelantoine1995@gmail.com>
---
 .../test-whatwg-encoding-custom-textencoder-short.js      | 8 --------
 1 file changed, 8 deletions(-)

diff --git a/test/parallel/test-whatwg-encoding-custom-textencoder-short.js b/test/parallel/test-whatwg-encoding-custom-textencoder-short.js
index 136edfed9d99..fb5774b78c94 100644
--- a/test/parallel/test-whatwg-encoding-custom-textencoder-short.js
+++ b/test/parallel/test-whatwg-encoding-custom-textencoder-short.js
@@ -32,11 +32,3 @@ for (const input of inputs) {
   assert.deepStrictEqual(Buffer.from(result), expected);
 }
 
-{
-  // Results must not share memory with each other.
-  const first = encoder.encode('first');
-  const second = encoder.encode('second');
-  assert.notStrictEqual(first.buffer, second.buffer);
-  assert.strictEqual(Buffer.from(first).toString(), 'first');
-  assert.strictEqual(Buffer.from(second).toString(), 'second');
-}

From 5f342bdc9e6f59da47b3a8dea92efb1953418e5a Mon Sep 17 00:00:00 2001
From: Mert Can Altin <mertgold60@gmail.com>
Date: Sun, 18 Oct 2026 16:58:00 +0300
Subject: [PATCH 3/3] lint

---
 test/parallel/test-whatwg-encoding-custom-textencoder-short.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/test/parallel/test-whatwg-encoding-custom-textencoder-short.js b/test/parallel/test-whatwg-encoding-custom-textencoder-short.js
index fb5774b78c94..3f8ad64b5673 100644
--- a/test/parallel/test-whatwg-encoding-custom-textencoder-short.js
+++ b/test/parallel/test-whatwg-encoding-custom-textencoder-short.js
@@ -31,4 +31,3 @@ for (const input of inputs) {
   assert.strictEqual(result.buffer.byteLength, expected.length);
   assert.deepStrictEqual(Buffer.from(result), expected);
 }
-