From 3ccdd306a5c40a81087f1eae29a7a73d83f8413c Mon Sep 17 00:00:00 2001
From: Sindre Sorhus <sindresorhus@gmail.com>
Date: Fri, 19 Sep 2025 12:40:42 +0900
Subject: [PATCH] Preserve complex values during deserialization

Fixes #76
---
 index.js |  8 ++++++--
 test.js  | 23 +++++++++++++++++++++++
 2 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/index.js b/index.js
index 29dd979..f1c050c 100644
--- a/index.js
+++ b/index.js
@@ -102,17 +102,21 @@ const destroyCircular = ({
 
 	for (const [key, value] of Object.entries(from)) {
 		if (value && value instanceof Uint8Array && value.constructor.name === 'Buffer') {
-			to[key] = '[object Buffer]';
+			to[key] = serialize ? '[object Buffer]' : value;
 			continue;
 		}
 
 		// TODO: Use `stream.isReadable()` when targeting Node.js 18.
 		if (value !== null && typeof value === 'object' && typeof value.pipe === 'function') {
-			to[key] = '[object Stream]';
+			to[key] = serialize ? '[object Stream]' : value;
 			continue;
 		}
 
 		if (typeof value === 'function') {
+			if (!serialize) {
+				to[key] = value;
+			}
+
 			continue;
 		}
 
diff --git a/test.js b/test.js
index db7864e..596970a 100644
--- a/test.js
+++ b/test.js
@@ -273,6 +273,29 @@ test('should deserialize plain object', t => {
 	t.is(deserialized.code, 'code');
 });
 
+test('should preserve buffers when deserializing', t => {
+	const buffer = Buffer.from([1, 2, 3]);
+	const deserialized = deserializeError({
+		message: 'buffer',
+		stack: '',
+		data: buffer,
+	});
+
+	t.true(Buffer.isBuffer(deserialized.data));
+	t.is(deserialized.data, buffer);
+});
+
+test('should preserve functions when deserializing', t => {
+	const sideEffect = () => 'no-op';
+	const deserialized = deserializeError({
+		message: 'function',
+		stack: '',
+		callback: sideEffect,
+	});
+
+	t.is(deserialized.callback, sideEffect);
+});
+
 for (const property of ['cause', 'any']) {
 	// `cause` is treated differently from other properties in the code
 	test(`should deserialize errors on ${property} property`, t => {