diff -r 000000000000 -r 6474c204b198 browser/metro/base/tests/mochitest/browser_circular_progress_indicator.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/metro/base/tests/mochitest/browser_circular_progress_indicator.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,57 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+let doc;
+
+function test() {
+  waitForExplicitFinish();
+  Task.spawn(function(){
+    info(chromeRoot + "browser_progress_indicator.xul");
+    yield addTab(chromeRoot + "browser_progress_indicator.xul");
+    doc = Browser.selectedTab.browser.contentWindow.document;
+  }).then(runTests);
+}
+
+gTests.push({
+  desc: "circular progress indicator binding is applied.",
+  run: function() {
+    ok(doc, "doc got defined");
+
+    let progressIndicator = doc.querySelector("#progress-indicator");
+    ok(progressIndicator, "progress-indicator is found");
+    is(typeof progressIndicator.reset, "function", "#progress-indicator has a reset() function");
+    is(typeof progressIndicator.updateProgress, "function", "#progress-indicator has a updateProgress() function");
+  }
+});
+
+gTests.push({
+  desc: "start and end angles are correct for various percents complete",
+  run: function() {
+    let progressIndicator = doc.querySelector("#progress-indicator");
+    ok(progressIndicator, "progress-indicator is found");
+    is(typeof progressIndicator.updateProgress, "function", "#progress-indicator has a updateProgress() function");
+
+    let expectedStartAngle = 1.5 * Math.PI;
+
+    let percentComplete = 0;
+    let [startAngle, endAngle] = progressIndicator.updateProgress(percentComplete);
+    is(startAngle, expectedStartAngle, "start angle is correct");
+    is(endAngle, startAngle + (2 * Math.PI * (percentComplete / 100)), "end angle is correct");
+
+    percentComplete = 0.05;
+    [startAngle, endAngle] = progressIndicator.updateProgress(percentComplete);
+    is(startAngle, expectedStartAngle, "start angle is correct");
+    is(endAngle, startAngle + (2 * Math.PI * (percentComplete / 100)), "end angle is correct");
+
+    percentComplete = 0.5;
+    [startAngle, endAngle] = progressIndicator.updateProgress(percentComplete);
+    is(startAngle, expectedStartAngle, "start angle is correct");
+    is(endAngle, startAngle + (2 * Math.PI * (percentComplete / 100)), "end angle is correct");
+
+    percentComplete = 1;
+    [startAngle, endAngle] = progressIndicator.updateProgress(percentComplete);
+    is(startAngle, expectedStartAngle, "start angle is correct");
+    is(endAngle, startAngle + (2 * Math.PI * (percentComplete / 100)), "end angle is correct");
+  }
+});
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