1 files changed, 60 insertions, 0 deletions
diff --git a/testing/web-platform/tests/speculation-rules/prerender/restriction-broadcast-channel.html b/testing/web-platform/tests/speculation-rules/prerender/restriction-broadcast-channel.html
new file mode 100644
index 0000000000..7225e64cf9
--- /dev/null
+++ b/testing/web-platform/tests/speculation-rules/prerender/restriction-broadcast-channel.html
@@ -0,0 +1,60 @@
+<!DOCTYPE html>
+<title>BroadcastChannel#postMessage is deferred</title>
+<meta name="timeout" content="long">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/common/utils.js"></script>
+<script src="resources/utils.js"></script>
+<body>
+<script>
+
+setup(() => assertSpeculationRulesIsSupported());
+
+promise_test(async t => {
+  const uid = token();
+  const bc = new PrerenderChannel('test-channel', uid);
+  t.add_cleanup(_ => bc.close());
+
+  const gotMessage = new Promise(resolve => {
+    bc.addEventListener('message', e => {
+      resolve(e.data);
+    }, {
+      once: true
+    });
+  });
+
+  const url = `resources/broadcast-channel.html?uid=${uid}`;
+  window.open(url, '_blank', 'noopener');
+
+  const result = await gotMessage;
+  const expected = [
+    {
+      event: 'started waiting BroadcastChannel',
+      prerendering: true
+    },
+    {
+      event: 'prerendering change',
+      prerendering: false
+    },
+    {
+      event: 'received message: hello',
+      prerendering: false
+    },
+    {
+      event: 'finished waiting BroadcastChannel',
+      prerendering: false
+    },
+  ];
+  assert_equals(result.length, expected.length);
+  for (let i = 0; i < result.length; i++) {
+    assert_equals(result[i].event, expected[i].event, `event${i}`);
+    assert_equals(result[i].prerendering, expected[i].prerendering,
+      `prerendering${i}`);
+  }
+
+  // Send a close signal to PrerenderEventCollector on the prerendered page.
+  new PrerenderChannel('close', uid).postMessage('');
+}, `BroadcastChannel#postMessage should be deferred until the prerendered ` +
+   `page is activated`);
+</script>
+</body>