1 files changed, 46 insertions, 0 deletions
diff --git a/testing/web-platform/tests/webmessaging/message-channels/detached-iframe.window.js b/testing/web-platform/tests/webmessaging/message-channels/detached-iframe.window.js
new file mode 100644
index 0000000000..c19f50ff93
--- /dev/null
+++ b/testing/web-platform/tests/webmessaging/message-channels/detached-iframe.window.js
@@ -0,0 +1,46 @@
+// META: title=MessageChannel in a detached iframe test
+// META: script=/service-workers/service-worker/resources/test-helpers.sub.js
+// META: script=/common/gc.js
+// Pull in the with_iframe helper function from the service worker tests
+
+
+const IframeAction = {
+  REMOVE_BEFORE_CREATION: 'remove-before-creation',
+  REMOVE_AFTER_CREATION: 'remove-after-creation',
+};
+
+async function detached_frame_test(t, action) {
+  const iframe = await with_iframe('about:blank');
+  const iframe_MessageChannel = iframe.contentWindow.MessageChannel;
+
+  if (action === IframeAction.REMOVE_BEFORE_CREATION) {
+    iframe.remove();
+  }
+
+  (() => {
+    const mc = new iframe_MessageChannel();
+    mc.port1.postMessage("boo");
+    mc.port2.onmessage = t.unreached_func("message event received");
+    mc.port2.onmessageerror = t.unreached_func("message event received");
+  })();
+
+  if (action === IframeAction.REMOVE_AFTER_CREATION) {
+    iframe.remove();
+  }
+
+  await garbageCollect();
+
+  // We are testing that neither of the above two events fire. We assume that a 2 second timeout
+  // is good enough. We can't use any other API for an end condition because each MessagePort has
+  // its own independent port message queue, which has no ordering guarantees relative to other
+  // APIs.
+  await new Promise(resolve => t.step_timeout(resolve, 2000));
+}
+
+promise_test(async (t) => {
+  return detached_frame_test(t, IframeAction.REMOVE_AFTER_CREATION);
+}, 'MessageChannel created from a detached iframe should not send messages (remove after create)');
+
+promise_test(async (t) => {
+  return detached_frame_test(t, IframeAction.REMOVE_BEFORE_CREATION);
+}, 'MessageChannel created from a detached iframe should not send messages (remove before create)');