1 files changed, 28 insertions, 0 deletions
diff --git a/testing/web-platform/tests/workers/support/shared-worker-partitioned-cookies-helper.js b/testing/web-platform/tests/workers/support/shared-worker-partitioned-cookies-helper.js
new file mode 100644
index 0000000000..e54d3848ae
--- /dev/null
+++ b/testing/web-platform/tests/workers/support/shared-worker-partitioned-cookies-helper.js
@@ -0,0 +1,28 @@
+// Return a generator containing the worker's message.
+//
+// Usage:
+//   const worker = new SharedWorker(...);
+//   const nextMessage = worker_message_generator(worker);
+//   const msg_1 = await nextMessage();
+//   const msg_2 = await nextMessage();
+//   const msg_3 = await nextMessage();
+function worker_message_generator(shared_worker) {
+  const buffer = [];
+  let resolve = null;
+
+  shared_worker.port.onmessage = message => {
+    buffer.push(message.data);
+    if (resolve) {
+      resolve();
+    }
+  }
+  shared_worker.port.start();
+
+  return async function() {
+    if (buffer.length != 0) {
+      return buffer.shift();
+    }
+    await new Promise(r => resolve = r);
+    return buffer.shift();
+  }
+}