1 files changed, 42 insertions, 0 deletions
diff --git a/testing/web-platform/tests/html/browsers/windows/nested-browsing-contexts/frameElement-siblings.sub.html b/testing/web-platform/tests/html/browsers/windows/nested-browsing-contexts/frameElement-siblings.sub.html
new file mode 100644
index 0000000000..0c814d26d9
--- /dev/null
+++ b/testing/web-platform/tests/html/browsers/windows/nested-browsing-contexts/frameElement-siblings.sub.html
@@ -0,0 +1,42 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>window.frameElement access to a same-origin-domain sibling</title>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+
+<iframe src="//{{hosts[][]}}:{{ports[http][0]}}/html/browsers/windows/nested-browsing-contexts/resources/frameElement-sibling-accessed.html"></iframe>
+<iframe src="//{{hosts[][www]}}:{{ports[http][0]}}/html/browsers/windows/nested-browsing-contexts/resources/frameElement-sibling-accessor.html"></iframe>
+
+<script>
+"use strict";
+setup({ explicit_done: true });
+
+window.onload = () => {
+  promise_test(async () => {
+    frames[1].postMessage({}, "*");
+    const result = await waitForMessage();
+
+    assert_equals(result, "SecurityError");
+  }, "it must give a \"SecurityError\" DOMException if the pages are different-origin domain");
+
+  promise_test(async () => {
+    document.domain = document.domain;
+
+    frames[0].postMessage({ newDocumentDomain: document.domain }, "*");
+    assert_equals(await waitForMessage(), "done");
+
+    frames[1].postMessage({ newDocumentDomain: document.domain }, "*");
+    const result = await waitForMessage();
+
+    assert_equals(result, "HTMLIFrameElement");
+  }, "it must return the iframe element if the pages are same-origin domain");
+
+  done();
+};
+
+function waitForMessage() {
+  return new Promise(resolve => {
+    window.addEventListener("message", e => resolve(e.data), { once: true });
+  });
+}
+</script>