1 files changed, 28 insertions, 0 deletions
diff --git a/devtools/client/responsive/test/xpcshell/test_change_user_agent.js b/devtools/client/responsive/test/xpcshell/test_change_user_agent.js
new file mode 100644
index 0000000000..e92d3f110f
--- /dev/null
+++ b/devtools/client/responsive/test/xpcshell/test_change_user_agent.js
@@ -0,0 +1,28 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// Test changing the user agent.
+
+const {
+  changeUserAgent,
+} = require("resource://devtools/client/responsive/actions/ui.js");
+
+const NEW_USER_AGENT =
+  "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_6) " +
+  "AppleWebKit/537.36 (KHTML, like Gecko) Chrome/68.0.3440.106 Safari/537.36";
+
+add_task(async function () {
+  const store = Store();
+  const { getState, dispatch } = store;
+
+  equal(getState().ui.userAgent, "", "User agent is empty by default.");
+
+  dispatch(changeUserAgent(NEW_USER_AGENT));
+  equal(
+    getState().ui.userAgent,
+    NEW_USER_AGENT,
+    `User Agent changed to ${NEW_USER_AGENT}`
+  );
+});