1 files changed, 18 insertions, 0 deletions
diff --git a/testing/web-platform/tests/webidl/ecmascript-binding/observable-array-no-leak-of-internals.window.js b/testing/web-platform/tests/webidl/ecmascript-binding/observable-array-no-leak-of-internals.window.js
new file mode 100644
index 0000000000..f93464005d
--- /dev/null
+++ b/testing/web-platform/tests/webidl/ecmascript-binding/observable-array-no-leak-of-internals.window.js
@@ -0,0 +1,18 @@
+"use strict";
+
+test(() => {
+  const observableArray = document.adoptedStyleSheets;
+
+  let leaked_target = null;
+  let leaked_handler = null;
+
+  let target_leaker = (target) => { leaked_target = target; return null; };
+  Object.defineProperty(Object.prototype, "getPrototypeOf", {get: function() {
+    leaked_handler = this;
+    return target_leaker;
+  }})
+  Object.getPrototypeOf(observableArray);
+
+  assert_equals(leaked_target, null, "The proxy target leaked.");
+  assert_equals(leaked_handler, null, "The proxy handler leaked.");
+}, "ObservableArray's internals won't leak");