From 93b57e6d8c62af0fc419332247a5f96aa5346833 Mon Sep 17 00:00:00 2001
From: davidot <david.tuin@gmail.com>
Date: Mon, 12 Jul 2021 01:30:04 +0200
Subject: [PATCH] LibJS: Disallow static methods named prototype in classes

---
 Userland/Libraries/LibJS/Parser.cpp | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Userland/Libraries/LibJS/Parser.cpp b/Userland/Libraries/LibJS/Parser.cpp
index 1c4412b0c6..a36a41e649 100644
--- a/Userland/Libraries/LibJS/Parser.cpp
+++ b/Userland/Libraries/LibJS/Parser.cpp
@@ -674,6 +674,12 @@ NonnullRefPtr<ClassExpression> Parser::parse_class_expression(bool expect_class_
                     break;
                 }
 
+                //https://tc39.es/ecma262/#sec-class-definitions-static-semantics-early-errors
+                // ClassElement : static MethodDefinition
+                //   It is a Syntax Error if PropName of MethodDefinition is "prototype".
+                if (is_static && name == "prototype"sv)
+                    syntax_error("Classes may not have a static property named 'prototype'");
+
             } else {
                 expected("property key");
             }