WebKit export of https://bugs.webkit.org/show_bug.cgi?id=203456 (#28037)
diff --git a/html/browsers/the-windowproxy-exotic-object/windowproxy-define-own-property-unforgeable-same-origin.html b/html/browsers/the-windowproxy-exotic-object/windowproxy-define-own-property-unforgeable-same-origin.html
new file mode 100644
index 0000000..ac4eb45
--- /dev/null
+++ b/html/browsers/the-windowproxy-exotic-object/windowproxy-define-own-property-unforgeable-same-origin.html
@@ -0,0 +1,47 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>[[DefineOwnProperty]] on a WindowProxy forwards to OrdinaryDefineOwnProperty for same-origin objects</title>
+<link rel="help" href="https://html.spec.whatwg.org/multipage/window-object.html#windowproxy-defineownproperty">
+
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+
+<script>
+"use strict";
+
+for (const key of ["window", "document", "location", "top"]) {
+ const { get, set } = Object.getOwnPropertyDescriptor(window, key);
+
+ test(() => {
+ Object.defineProperty(window, key, {});
+ assert_true(Reflect.defineProperty(window, key, { configurable: false }), "[[Configurable]]: false");
+ Object.defineProperty(window, key, { enumerable: true });
+
+ assert_true(Reflect.defineProperty(window, key, { get }), "[[Get]]: unchanged");
+ Object.defineProperty(window, key, { set });
+ assert_true(Reflect.defineProperty(window, key, { get, set }), "[[Get]]: unchanged, [[Set]]: unchanged");
+
+ Object.defineProperty(window, key, { get, set, enumerable: true, configurable: false });
+ }, `[[DefineOwnProperty]] success: "${key}"`);
+
+ test(() => {
+ assert_throws_js(TypeError, () => {
+ Object.defineProperty(window, key, { configurable: true });
+ }, "[[Configurable]]: true");
+
+ assert_false(Reflect.defineProperty(window, key, { enumerable: false }), "[[Enumerable]]: false");
+
+ assert_throws_js(TypeError, () => {
+ Object.defineProperty(window, key, { get() {}, set });
+ }, "[[Get]]: changed, [[Set]]: unchanged");
+
+ assert_false(Reflect.defineProperty(window, key, { get, set() {} }), "[[Get]]: unchanged, [[Set]]: changed");
+
+ assert_throws_js(TypeError, () => {
+ Object.defineProperty(window, key, { writable: false, configurable: true });
+ }, "[[Writable]]: false, [[Configurable]]: true");
+
+ assert_false(Reflect.defineProperty(window, key, { value: window[key], enumerable: true }), "[[Value]], [[Enumerable]]: true");
+ }, `[[DefineOwnProperty]] failure: "${key}"`);
+}
+</script>
