1 files changed, 36 insertions, 0 deletions
diff --git a/docshell/test/browser/browser_ua_emulation.js b/docshell/test/browser/browser_ua_emulation.js
new file mode 100644
index 000000000..94a602d4b
--- /dev/null
+++ b/docshell/test/browser/browser_ua_emulation.js
@@ -0,0 +1,36 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+const URL = "data:text/html;charset=utf-8,<iframe id='test-iframe'></iframe>";
+
+// Test that the docShell UA emulation works
+function* contentTask() {
+  let docshell = docShell;
+  is(docshell.customUserAgent, "", "There should initially be no customUserAgent");
+
+  docshell.customUserAgent = "foo";
+  is(content.navigator.userAgent, "foo", "The user agent should be changed to foo");
+
+  let frameWin = content.document.querySelector("#test-iframe").contentWindow;
+  is(frameWin.navigator.userAgent, "foo", "The UA should be passed on to frames.");
+
+  let newFrame = content.document.createElement("iframe");
+  content.document.body.appendChild(newFrame);
+
+  let newFrameWin = newFrame.contentWindow;
+  is(newFrameWin.navigator.userAgent, "foo", "Newly created frames should use the new UA");
+
+  newFrameWin.location.reload();
+  yield ContentTaskUtils.waitForEvent(newFrameWin, "load");
+
+  is(newFrameWin.navigator.userAgent, "foo", "New UA should persist across reloads");
+}
+
+add_task(function* () {
+  yield BrowserTestUtils.withNewTab({ gBrowser, url: URL },
+    function* (browser) {
+      yield ContentTask.spawn(browser, null, contentTask);
+    });
+});