1 files changed, 95 insertions, 0 deletions
diff --git a/testing/web-platform/tests/service-workers/service-worker/resources/about-blank-replacement-worker.js b/testing/web-platform/tests/service-workers/service-worker/resources/about-blank-replacement-worker.js
new file mode 100644
index 0000000000..f43598e41c
--- /dev/null
+++ b/testing/web-platform/tests/service-workers/service-worker/resources/about-blank-replacement-worker.js
@@ -0,0 +1,95 @@
+// Helper routine to find a client that matches a particular URL.  Note, we
+// require that Client to be controlled to avoid false matches with other
+// about:blank windows the browser might have.  The initial about:blank should
+// inherit the controller from its parent.
+async function getClientByURL(url) {
+  let list = await clients.matchAll();
+  return list.find(client => client.url === url);
+}
+
+// Helper routine to perform a ping-pong with the given target client.  We
+// expect the Client to respond with its location URL.
+async function pingPong(target) {
+  function waitForPong() {
+    return new Promise(resolve => {
+      self.addEventListener('message', function onMessage(evt) {
+        if (evt.data.type === 'PONG') {
+          resolve(evt.data.location);
+        }
+      });
+    });
+  }
+
+  target.postMessage({ type: 'PING' })
+  return await waitForPong(target);
+}
+
+addEventListener('fetch', async evt => {
+  let url = new URL(evt.request.url);
+  if (!url.searchParams.get('nested')) {
+    return;
+  }
+
+  evt.respondWith(async function() {
+    // Find the initial about:blank document.
+    const client = await getClientByURL('about:blank');
+    if (!client) {
+      return new Response('failure: could not find about:blank client');
+    }
+
+    // If the nested frame is configured to support a ping-pong, then
+    // ping it now to verify its message listener exists.  We also
+    // verify the Client's idea of its own location URL while we are doing
+    // this.
+    if (url.searchParams.get('ping')) {
+      const loc = await pingPong(client);
+      if (loc !== 'about:blank') {
+        return new Response(`failure: got location {$loc}, expected about:blank`);
+      }
+    }
+
+    // Finally, allow the nested frame to complete loading.  We place the
+    // Client ID we found for the initial about:blank in the body.
+    return new Response(client.id);
+  }());
+});
+
+addEventListener('message', evt => {
+  if (evt.data.type !== 'GET_CLIENT_ID') {
+    return;
+  }
+
+  evt.waitUntil(async function() {
+    let url = new URL(evt.data.url);
+
+    // Find the given Client by its URL.
+    let client = await getClientByURL(evt.data.url);
+    if (!client) {
+      evt.source.postMessage({
+        type: 'GET_CLIENT_ID',
+        result: `failure: could not find ${evt.data.url} client`
+      });
+      return;
+    }
+
+    // If the Client supports a ping-pong, then do it now to verify
+    // the message listener exists and its location matches the
+    // Client object.
+    if (url.searchParams.get('ping')) {
+      let loc = await pingPong(client);
+      if (loc !== evt.data.url) {
+        evt.source.postMessage({
+          type: 'GET_CLIENT_ID',
+          result: `failure: got location ${loc}, expected ${evt.data.url}`
+        });
+        return;
+      }
+    }
+
+    // Finally, send the client ID back.
+    evt.source.postMessage({
+      type: 'GET_CLIENT_ID',
+      result: client.id
+    });
+  }());
+});