Mocha adapter for Polymer browser tests.

chrome/test/data/webui/polymer_browser_test_base.js

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+/**
+ * @fileoverview Framework for running JavaScript tests of Polymer elements.
+ */
+
+/**
+ * Test fixture for Polymer element testing.
+ * @constructor
+ * @extends testing.Test
+ */
+function PolymerTest() {
+}
+
+PolymerTest.prototype = {
+  __proto__: testing.Test.prototype,
+
+  /**
+   * Navigate to a WebUI to satisfy BrowserTest conditions. Override to load a
+   * more useful WebUI.
+   * @override
+   */
+  browsePreload: 'chrome://chrome-urls/',

[Dan Beam, 2015/06/02 21:44:50]

whatever this is satisfying: can we just turn it off?

[michaelpg, 2015/06/02 22:57:58]

I didn't look too much into this. If we remove the assert, the test just
silently fails. Presumably the WebUI is involved in communicating the status of
the test. It's something we'll have to tackle, but I don't think it's pressing.

+
+  /**
+   * The mocha adapter assumes all tests are async.
+   * @override
+   * @final
+   */
+  isAsync: true,
+
+  /**
+   * @override
+   * @final
+   */
+  extraLibraries: ['../../../../third_party/mocha/mocha.js',
+                   'mocha_adapter.js'],
+
+  setUp: function() {

[Dan Beam, 2015/06/02 21:44:50]

is this supposed to be @overridden?
https://code.google.com/p/chromium/codesearch#chromium/src/chrome/test/data/w...

e.g.

  /** @override */

  testing.Test.prototype.setUp.call(this);
  ... rest of code ...

[Dan Beam, 2015/06/02 21:44:50]

setUpPage instead?

[michaelpg, 2015/06/02 22:57:58]

Done.

+    // Import Polymer before running tests.
+    suiteSetup(function(done) {
+      var link = document.createElement('link');
+      link.rel = 'import';
+      link.onload = function() {
+        done();
+      };
+      link.onerror = function() {
+        done(new Error('Failed to load Polymer!'));
+      };
+      link.href = 'chrome://resources/polymer/v0_8/polymer/polymer.html';
+      document.head.appendChild(link);
+    });
+  },
+};
+
+/**
+ * Imports the HTML file, then calls |done| on success or throws an error.
+ * @param {String} href The URL to load.
+ * @param {Function} done The done callback.
+ */
+PolymerTest.importHref = function(href, done) {
+  Polymer.Base.importHref(
+      href,
+      function() { done(); },
+      function() { throw new Error('Failed to load ' + href); });
+};
+
+/**
+ * Removes all content from the body.
+ */
+PolymerTest.clearBody = function() {
+  document.body.innerHTML = '';
+};