src/tools/telemetry/telemetry/page/actions/pinch.py

   1 # Copyright 2013 The Chromium Authors. All rights reserved.
   2 # Use of this source code is governed by a BSD-style license that can be
   3 # found in the LICENSE file.
   4 import os
   5
   6 from telemetry.page.actions import page_action
   7
   8
   9 class PinchAction(page_action.PageAction):
  10   def __init__(self, selector=None, text=None, element_function=None,
  11                left_anchor_ratio=0.5, top_anchor_ratio=0.5,
  12                scale_factor=None, speed_in_pixels_per_second=800):
  13     super(PinchAction, self).__init__()
  14     self._selector = selector
  15     self._text = text
  16     self._element_function = element_function
  17     self._left_anchor_ratio = left_anchor_ratio
  18     self._top_anchor_ratio = top_anchor_ratio
  19     self._scale_factor = scale_factor
  20     self._speed = speed_in_pixels_per_second
  21
  22     if (self._selector is None and self._text is None and
  23         self._element_function is None):
  24       self._element_function = 'document.body'
  25
  26   def WillRunAction(self, tab):
  27     for js_file in ['gesture_common.js', 'pinch.js']:
  28       with open(os.path.join(os.path.dirname(__file__), js_file)) as f:
  29         js = f.read()
  30         tab.ExecuteJavaScript(js)
  31
  32     # Fail if browser doesn't support synthetic pinch gestures.
  33     if not tab.EvaluateJavaScript('window.__PinchAction_SupportedByBrowser()'):
  34       raise page_action.PageActionNotSupported(
  35           'Synthetic pinch not supported for this browser')
  36
  37     # TODO(dominikg): Remove once JS interface changes have rolled into stable.
  38     if not tab.EvaluateJavaScript('chrome.gpuBenchmarking.newPinchInterface'):
  39       raise page_action.PageActionNotSupported(
  40           'This version of the browser doesn\'t support the new JS interface '
  41           'for pinch gestures.')
  42
  43     if (page_action.GetGestureSourceTypeFromOptions(tab) ==
  44         'chrome.gpuBenchmarking.MOUSE_INPUT'):
  45       raise page_action.PageActionNotSupported(
  46           'Pinch page action does not support mouse input')
  47
  48     if not page_action.IsGestureSourceTypeSupported(tab, 'touch'):
  49       raise page_action.PageActionNotSupported(
  50           'Touch input not supported for this browser')
  51
  52     done_callback = 'function() { window.__pinchActionDone = true; }'
  53     tab.ExecuteJavaScript("""
  54         window.__pinchActionDone = false;
  55         window.__pinchAction = new __PinchAction(%s);"""
  56         % done_callback)
  57
  58   @staticmethod
  59   def _GetDefaultScaleFactorForPage(tab):
  60     current_scale_factor = tab.EvaluateJavaScript(
  61         'window.outerWidth / window.innerWidth')
  62     return 3.0 / current_scale_factor
  63
  64   def RunAction(self, tab):
  65     scale_factor = (self._scale_factor if self._scale_factor else
  66                     PinchAction._GetDefaultScaleFactorForPage(tab))
  67     code = '''
  68         function(element, info) {
  69           if (!element) {
  70             throw Error('Cannot find element: ' + info);
  71           }
  72           window.__pinchAction.start({
  73             element: element,
  74             left_anchor_ratio: %s,
  75             top_anchor_ratio: %s,
  76             scale_factor: %s,
  77             speed: %s
  78           });
  79         }''' % (self._left_anchor_ratio,
  80                 self._top_anchor_ratio,
  81                 scale_factor,
  82                 self._speed)
  83     page_action.EvaluateCallbackWithElement(
  84         tab, code, selector=self._selector, text=self._text,
  85         element_function=self._element_function)
  86     tab.WaitForJavaScriptExpression('window.__pinchActionDone', 60)