[MD settings] idle load basic and advanced pages

chrome/test/data/webui/settings/settings_idle_render_browsertest.js

Index: chrome/test/data/webui/settings/settings_idle_render_browsertest.js
diff --git a/chrome/test/data/webui/settings/settings_idle_render_browsertest.js b/chrome/test/data/webui/settings/settings_idle_render_browsertest.js
new file mode 100644
index 0000000000000000000000000000000000000000..8f3b42138e6c0d2db8aa4c3e0492b48e583710c5
--- /dev/null
+++ b/chrome/test/data/webui/settings/settings_idle_render_browsertest.js
@@ -0,0 +1,67 @@
+// Copyright 2017 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 Tests for settings-idle-render. */
+
+/** @const {string} Path to root from chrome/test/data/webui/settings/. */
+var ROOT_PATH = '../../../../../';
+
+/**
+ * @constructor
+ * @extends testing.Test
+ */
+function SettingsIdleRenderBrowserTest() {}
+
+SettingsIdleRenderBrowserTest.prototype = {
+  __proto__: testing.Test.prototype,

[Dan Beam, 2017/02/07 07:21:33]

why is this in its own file? instead of being a settings test?

[dschuyler, 2017/02/07 19:54:30]

I thought it was the right thing to do. There's likely a nuance of the test
styles that I'm missing. Let's chat further about how this can be improved and
I'll do that in a follow-up CL. Since this has an LGTM and there is a unit test
- I'm interpreting this as being 'okay, but could be improved'.

+
+  /** @override */
+  browsePreload: 'chrome://md-settings/controls/setting_idle_render.html',
+
+  /** @override */
+  extraLibraries: [
+    ROOT_PATH + 'third_party/mocha/mocha.js',
+    '../mocha_adapter.js',
+  ],
+
+  /** @override */
+  isAsync: true,
+
+  /** @override */
+  runAccessibilityChecks: false,
+};
+
+TEST_F('SettingsIdleRenderBrowserTest', 'render', function() {
+  // Register mocha tests.
+  suite('Settings idle render tests', function() {
+    setup(function() {
+      var template =
+          '<template is="settings-idle-render" id="idleTemplate">' +
+          '  <div>' +
+          '  </div>' +
+          '</template>';
+      document.body.innerHTML = template;
+      // The div should not be initially accesible.
+      assertFalse(!!document.body.querySelector('div'));
+    });
+
+    test('stamps after get()', function() {
+      // Calling get() will force stamping without waiting for idle time.
+      var inner = document.getElementById('idleTemplate').get();
+      assertEquals('DIV', inner.nodeName);
+      assertEquals(inner, document.body.querySelector('div'));
+    });
+
+    test('stamps after idle', function(done) {
+      requestIdleCallback(function() {
+        // After JS calls idle-callbacks, this should be accesible.
+        assertTrue(!!document.body.querySelector('div'));
+        done();
+      });
+    });
+  });
+
+  // Run all registered tests.
+  mocha.run();
+});