1 files changed, 174 insertions, 0 deletions
diff --git a/testing/web-platform/tests/webmessaging/broadcastchannel/detached-iframe.html b/testing/web-platform/tests/webmessaging/broadcastchannel/detached-iframe.html
new file mode 100644
index 0000000000..b9b06c3a46
--- /dev/null
+++ b/testing/web-platform/tests/webmessaging/broadcastchannel/detached-iframe.html
@@ -0,0 +1,174 @@
+<!DOCTYPE html>
+<meta charset=utf-8>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/common/get-host-info.sub.js"></script>
+<!-- Pull in the with_iframe helper function from the service worker tests -->
+<script src="/service-workers/service-worker/resources/test-helpers.sub.js"></script>
+<body>
+<script>
+const TEST_IFRAME_CLASS_NAME = 'test-iframe';
+const events = [];
+var bc1;
+const DONE_MSG = 'done';
+
+function DetachedIframeTestCheckForOneMessage(t) {
+  return new Promise((resolve) => {
+    bc1.onmessage = t.step_func(e => {
+      events.push(e);
+      if (e.data == DONE_MSG) {
+        assert_equals(events.length, 1);
+        resolve();
+      }
+    });
+  });
+}
+
+const IframeAction = {
+  REMOVE_BEFORE_CREATION: 'remove-before-creation',
+  REMOVE_AFTER_CREATION: 'remove-after-creation',
+};
+
+async function doMessageSentTest(t, channelName, action) {
+  await with_iframe('about:blank');
+  const iframe = document.getElementsByClassName(TEST_IFRAME_CLASS_NAME)[0];
+  const iframe_BroadcastChannel = iframe.contentWindow.BroadcastChannel;
+
+  if (action === IframeAction.REMOVE_BEFORE_CREATION) {
+    iframe.remove();
+  }
+
+  events.length = 0;
+
+  bc1 = new BroadcastChannel(channelName);
+  const bc2 = new BroadcastChannel(channelName);
+  const iframe_bc = new iframe_BroadcastChannel(channelName);
+
+  if (action === IframeAction.REMOVE_AFTER_CREATION) {
+    iframe.remove();
+  }
+
+  const testResultsPromise = DetachedIframeTestCheckForOneMessage(t);
+
+  iframe_bc.postMessage('test');
+  bc2.postMessage(DONE_MSG);
+
+  bc2.close();
+  iframe_bc.close();
+  t.add_cleanup(() => bc1.close());
+
+  return testResultsPromise;
+}
+
+promise_test(async t => {
+  return doMessageSentTest(
+      t, 'postMessage-from-detached-iframe-pre',
+      IframeAction.REMOVE_AFTER_CREATION);
+}, 'BroadcastChannel messages from detached iframe to parent should be ignored (BC created before detaching)');
+
+promise_test(async t => {
+  return doMessageSentTest(
+      t, 'postMessage-from-detached-iframe-post',
+      IframeAction.REMOVE_BEFORE_CREATION);
+}, 'BroadcastChannel messages from detached iframe to parent should be ignored (BC created after detaching)');
+
+
+async function doMessageReceivedTest(t, channelName, action) {
+  await with_iframe('about:blank');
+  const iframe = document.getElementsByClassName(TEST_IFRAME_CLASS_NAME)[0];
+  const iframe_BroadcastChannel = iframe.contentWindow.BroadcastChannel;
+
+  if (action === IframeAction.REMOVE_BEFORE_CREATION) {
+    iframe.remove();
+  }
+
+  events.length = 0;
+
+  // `iframe_bc` must be created first so that it receives messages before
+  // `bc1`. That way we can tell whether `iframe_bc` received a message by
+  // inspecting `events` in the `bc1` message handler.
+  const iframe_bc = new iframe_BroadcastChannel(channelName);
+  iframe_bc.onmessage = e => {
+    events.push(e)
+  };
+  bc1 = new BroadcastChannel(channelName);
+  const bc2 = new BroadcastChannel(channelName);
+
+  if (action === IframeAction.REMOVE_AFTER_CREATION) {
+    iframe.remove();
+  }
+
+  const testResultsPromise = DetachedIframeTestCheckForOneMessage(t);
+  bc2.postMessage(DONE_MSG);
+
+  bc2.close();
+  iframe_bc.close();
+  t.add_cleanup(() => bc1.close());
+}
+
+promise_test(async t => {
+  return doMessageReceivedTest(
+      t, 'postMessage-to-detached-iframe-pre',
+      IframeAction.REMOVE_AFTER_CREATION);
+}, 'BroadcastChannel messages from parent to detached iframe should be ignored (BC created before detaching)');
+
+promise_test(async t => {
+  return doMessageReceivedTest(
+      t, 'postMessage-to-detached-iframe-post',
+      IframeAction.REMOVE_BEFORE_CREATION);
+}, 'BroadcastChannel messages from parent to detached iframe should be ignored (BC created after detaching)');
+
+
+async function doMessageSendReceiveTest(t, channelName, action) {
+  await with_iframe('about:blank');
+  const iframe = document.getElementsByClassName(TEST_IFRAME_CLASS_NAME)[0];
+  const iframe_BroadcastChannel = iframe.contentWindow.BroadcastChannel;
+
+  if (action === IframeAction.REMOVE_BEFORE_CREATION) {
+    iframe.remove();
+  }
+
+  const iframe_bc1 = new iframe_BroadcastChannel(channelName);
+  const iframe_bc2 = new iframe_BroadcastChannel(channelName);
+  iframe_bc1.onmessage = t.unreached_func(
+      'Detached iframe BroadcastChannel instance received message unexpectedly');
+
+  if (action === IframeAction.REMOVE_AFTER_CREATION) {
+    iframe.remove();
+  }
+
+  iframe_bc2.postMessage(DONE_MSG);
+
+  iframe_bc2.close();
+  t.add_cleanup(() => iframe_bc1.close());
+
+  // To avoid calling t.step_timeout here, instead just create two new
+  // BroadcastChannel instances and complete the test when a message is passed
+  // between them.  Per the spec, all "BroadcastChannel objects whose relevant
+  // agents are the same" must have messages delivered to them in creation
+  // order, so if we get this message then it's safe to assume the earlier
+  // message would have been delivered if it was going to be.
+  const bc1 = new BroadcastChannel(channelName);
+  const bc2 = new BroadcastChannel(channelName);
+  return new Promise((resolve) => {
+    bc1.onmessage = t.step_func(e => {
+      resolve();
+    });
+    bc2.postMessage(DONE_MSG);
+  });
+}
+
+promise_test(async t => {
+  return doMessageSendReceiveTest(
+      t, 'postMessage-within-detached-iframe-pre',
+      IframeAction.REMOVE_AFTER_CREATION);
+}, 'BroadcastChannel messages within detached iframe should be ignored (BCs created before detaching)');
+
+promise_test(async t => {
+  return doMessageSendReceiveTest(
+      t, 'postMessage-within-detached-iframe-post',
+      IframeAction.REMOVE_BEFORE_CREATION);
+}, 'BroadcastChannel messages within detached iframe should be ignored (BCs created after detaching)');
+
+</script>
+</body>