1 files changed, 68 insertions, 0 deletions
diff --git a/devtools/server/tracer/tests/browser/browser_worker_tracer.js b/devtools/server/tracer/tests/browser/browser_worker_tracer.js
new file mode 100644
index 0000000000..815da85853
--- /dev/null
+++ b/devtools/server/tracer/tests/browser/browser_worker_tracer.js
@@ -0,0 +1,68 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+const wdm = Cc["@mozilla.org/dom/workers/workerdebuggermanager;1"].getService(
+  Ci.nsIWorkerDebuggerManager
+);
+
+const BASE_URL =
+  "chrome://mochitests/content/browser/devtools/server/tracer/tests/browser/";
+const WORKER_URL = BASE_URL + "Worker.tracer.js";
+const WORKER_DEBUGGER_URL = BASE_URL + "WorkerDebugger.tracer.js";
+
+add_task(async function testTracingWorker() {
+  const onDbg = waitForWorkerDebugger(WORKER_URL);
+
+  info("Instantiate a regular worker");
+  const worker = new Worker(WORKER_URL);
+  info("Wait for worker to reply back");
+  await new Promise(r => (worker.onmessage = r));
+  info("Wait for WorkerDebugger to be instantiated");
+  const dbg = await onDbg;
+
+  const onDebuggerScriptSentFrames = new Promise(resolve => {
+    const listener = {
+      onMessage(msg) {
+        dbg.removeListener(listener);
+        resolve(JSON.parse(msg));
+      },
+    };
+    dbg.addListener(listener);
+  });
+  info("Evaluate a Worker Debugger test script");
+  dbg.initialize(WORKER_DEBUGGER_URL);
+
+  info("Wait for frames to be notified by the debugger script");
+  const frames = await onDebuggerScriptSentFrames;
+
+  is(frames.length, 3);
+  // There is a third frame which relates to the usage of Debugger.Object.executeInGlobal
+  // which we ignore as that's a test side effect.
+  const lastFrame = frames.at(-1);
+  const beforeLastFrame = frames.at(-2);
+  is(beforeLastFrame.depth, 1);
+  is(beforeLastFrame.formatedDisplayName, "λ foo");
+  is(beforeLastFrame.prefix, "testWorkerPrefix: ");
+  ok(beforeLastFrame.frame);
+  is(lastFrame.depth, 2);
+  is(lastFrame.formatedDisplayName, "λ bar");
+  is(lastFrame.prefix, "testWorkerPrefix: ");
+  ok(lastFrame.frame);
+});
+
+function waitForWorkerDebugger(url, dbgUrl) {
+  return new Promise(function (resolve) {
+    wdm.addListener({
+      onRegister(dbg) {
+        if (dbg.url !== url) {
+          return;
+        }
+        ok(true, "Debugger with url " + url + " should be registered.");
+        wdm.removeListener(this);
+        resolve(dbg);
+      },
+    });
+  });
+}