1 files changed, 29 insertions, 0 deletions
diff --git a/js/xpconnect/tests/unit/test_messageChannel.js b/js/xpconnect/tests/unit/test_messageChannel.js
new file mode 100644
index 0000000000..685aa10e43
--- /dev/null
+++ b/js/xpconnect/tests/unit/test_messageChannel.js
@@ -0,0 +1,29 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+add_task(async function() {
+  let sb = new Cu.Sandbox('http://www.example.com',
+                          { wantGlobalProperties: ["MessageChannel"] });
+  sb.ok = ok;
+  Cu.evalInSandbox('ok((new MessageChannel()) instanceof MessageChannel);',
+                   sb);
+  Cu.evalInSandbox('ok((new MessageChannel()).port1 instanceof MessagePort);',
+                   sb);
+
+  Cu.importGlobalProperties(["MessageChannel"]);
+
+  let mc = new MessageChannel();
+  Assert.ok(mc instanceof MessageChannel);
+  Assert.ok(mc.port1 instanceof MessagePort);
+  Assert.ok(mc.port2 instanceof MessagePort);
+
+  mc.port1.postMessage(42);
+
+  let result = await new Promise(resolve => {
+    mc.port2.onmessage = e => {
+      resolve(e.data);
+    }
+  });
+
+  Assert.equal(result, 42);
+});