[chrome-remote-control] Interaction objects separate measurement/test code from page scrolling/drag…

tools/chrome_remote_control/chrome_remote_control/scroll_interaction.py

Index: tools/chrome_remote_control/chrome_remote_control/scroll_interaction.py
diff --git a/tools/chrome_remote_control/chrome_remote_control/scroll_interaction.py b/tools/chrome_remote_control/chrome_remote_control/scroll_interaction.py
new file mode 100644
index 0000000000000000000000000000000000000000..67a1af85d8976d4be14b11bd7100b4454626696d
--- /dev/null
+++ b/tools/chrome_remote_control/chrome_remote_control/scroll_interaction.py
@@ -0,0 +1,67 @@
+# Copyright (c) 2012 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.
+import os
+
+from chrome_remote_control import interaction
+from chrome_remote_control import page_test
+from chrome_remote_control import util
+
+class ScrollInteraction(interaction.Interaction):
+  def __init__(self, use_gpu_benchmarking_extension=True):
+    super(ScrollInteraction, self).__init__()
+    self._use_gpu_benchmarking_extension = use_gpu_benchmarking_extension
+
+  def CustomizeBrowserOptions(self, options):
+    if self._use_gpu_benchmarking_extension:
+      options.extra_browser_args.append('--enable-gpu-benchmarking')
+
+  def SupportedForPage(self, page, tab):
+    # TODO(nduca): Detect if the page isn't scrollable up front and raise an
+    # interaction.InteractionNotSupported.
+    return True
+
+  def PerformInteraction(self, page, tab, test):
+    scroll_js_path = os.path.join(os.path.dirname(__file__),
+                                  'scroll.js')
+    scroll_js = open(scroll_js_path, 'r').read()
+
+    # Run scroll test.
+    tab.runtime.Execute(scroll_js)
+
+    start_scroll_js = """
+      window.__renderingStatsDeltas = null;
+      window.__scrollElement = element;
+      new __ScrollTest(function(rendering_stats_deltas) {
+        window.__renderingStatsDeltas = rendering_stats_deltas;
+      }).start(element);
+    """
+    # scrollable_element_function is a function that passes the scrollable
+    # element on the page to a callback. For example:
+    #   function (callback) {
+    #     callback(document.getElementById('foo'));
+    #   }
+    test.WillPerformInteraction(self, page, tab)
+
+    if hasattr(page, 'scrollable_element_function'):
+      tab.runtime.Execute('(%s)(function(element) { %s });' %
+                          (page.scrollable_element_function, start_scroll_js))
+    else:
+      tab.runtime.Execute('(function() { var element = document.body; %s})();' %
+                          start_scroll_js)
+
+    # Poll for scroll benchmark completion.
+    util.WaitFor(lambda: tab.runtime.Evaluate(
+        'window.__renderingStatsDeltas'), 60)
+
+    rendering_stats_deltas = tab.runtime.Evaluate(
+      'window.__renderingStatsDeltas')
+
+    if not (rendering_stats_deltas['numFramesSentToScreen'] > 0):
+      raise page_test.Failure('Interaction failed: Page did not scroll!')
+    test.DidPerformInteraction(self, page, tab, rendering_stats_deltas)
+
+  def CleanUp(self, page, tab):
+    tab.runtime.Execute('window.__scrollElement.scrollTop = 0;')
+
+interaction.RegisterClass('scroll', ScrollInteraction)