From b690ed21af83621c1c3e99d0b47772cbd692f1ff Mon Sep 17 00:00:00 2001
From: KATT <alexander@n1s.se>
Date: Tue, 20 Jul 2021 00:25:18 +0200
Subject: [PATCH 1/2] add failing test

---
 src/index.test.ts | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/index.test.ts b/src/index.test.ts
index fd162e8..2fdce8c 100644
--- a/src/index.test.ts
+++ b/src/index.test.ts
@@ -936,3 +936,13 @@ test('regression #108: Error#stack should not be included by default', () => {
   ) as any;
   expect(thatShouldExist).toEqual(input.stack);
 });
+
+test('regression: `Object.create(null)` / object without prototype', () => {
+  const input: Record<string, unknown> = Object.create(null);
+  input.date = new Date();
+
+  const stringified = SuperJSON.stringify(input);
+  const parsed: any = SuperJSON.parse(stringified);
+
+  expect(parsed.date).toBeInstanceOf(Date);
+});

From c5ebb655572cdb21015db46b3b42b080f518e63a Mon Sep 17 00:00:00 2001
From: Simon Knott <info@simonknott.de>
Date: Tue, 27 Jul 2021 10:03:49 +0200
Subject: [PATCH 2/2] consider null-prototype object a "plain" object

---
 src/is.test.ts | 6 ++++++
 src/is.ts      | 1 +
 2 files changed, 7 insertions(+)

diff --git a/src/is.test.ts b/src/is.test.ts
index 54c8ade..c94b22f 100644
--- a/src/is.test.ts
+++ b/src/is.test.ts
@@ -9,6 +9,7 @@ import {
   isString,
   isSymbol,
   isUndefined,
+  isPlainObject,
 } from './is';
 
 test('Basic true tests', () => {
@@ -68,3 +69,8 @@ test('Primitive tests', () => {
 test('Date exception', () => {
   expect(isDate(new Date('_'))).toBe(false);
 });
+
+test('Regression: null-prototype object', () => {
+  expect(isPlainObject(Object.create(null))).toBe(true);
+  expect(isPrimitive(Object.create(null))).toBe(false);
+});
diff --git a/src/is.ts b/src/is.ts
index 9fceb9f..010c10f 100644
--- a/src/is.ts
+++ b/src/is.ts
@@ -10,6 +10,7 @@ export const isPlainObject = (
   payload: any
 ): payload is { [key: string]: any } => {
   if (getType(payload) !== 'Object') return false;
+  if (Object.getPrototypeOf(payload) === null) return true;
   return (
     payload.constructor === Object &&
     Object.getPrototypeOf(payload) === Object.prototype