1 files changed, 30 insertions, 0 deletions
diff --git a/toolkit/components/resistfingerprinting/tests/browser/testHelpers.js b/toolkit/components/resistfingerprinting/tests/browser/testHelpers.js
new file mode 100644
index 0000000000..3feb5dfc11
--- /dev/null
+++ b/toolkit/components/resistfingerprinting/tests/browser/testHelpers.js
@@ -0,0 +1,30 @@
+async function registerServiceWorker(win, url) {
+  let reg = await win.navigator.serviceWorker.register(url);
+  if (reg.installing.state !== "activated") {
+    await new Promise(resolve => {
+      let w = reg.installing;
+      w.addEventListener("statechange", function onStateChange() {
+        if (w.state === "activated") {
+          w.removeEventListener("statechange", onStateChange);
+          resolve();
+        }
+      });
+    });
+  }
+
+  return reg.active;
+}
+
+function sendAndWaitWorkerMessage(target, worker, message) {
+  return new Promise(resolve => {
+    worker.addEventListener(
+      "message",
+      msg => {
+        resolve(msg.data);
+      },
+      { once: true }
+    );
+
+    target.postMessage(message);
+  });
+}