tools: Local tests for the speculative prefetch predictor.

tools/resource_prefetch_predictor/common.py

+# Copyright 2016 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.
+
+"""Common utils for the speculative resource prefetch evaluation."""
+
+import argparse
+import logging
+import os
+import sys
+
+_SRC_PATH = os.path.abspath(os.path.join(
+    os.path.dirname(__file__), os.pardir, os.pardir))
+
+sys.path.append(os.path.join(_SRC_PATH, 'third_party', 'catapult', 'devil'))
+from devil.android import device_utils
+
+sys.path.append(os.path.join(_SRC_PATH, 'tools', 'android', 'loading'))
+import controller
+from options import OPTIONS
+
+
+def CreateBaseArgumentParser(description):

[pasko, 2016/11/17 15:59:04]

inlining this function on every use will increase readability, won't add many
lines of code, please do

[Benoit L, 2016/11/21 13:40:32]

Done.

+  """Returns a new ArgumentParser instance with a |description|."""
+  return argparse.ArgumentParser(description=description,
+                                 parents=[OPTIONS.GetParentParser()])
+
+
+def ParseAndReturnArgs(parser):

[pasko, 2016/11/17 15:59:04]

as the above, this utility is quite small and does not provide much value, adds
another hop to see what it means when reading the code.

if it were part of tools/android/loading, that would have been probably a better
incapsulation (i.e. avoided directly exposing OPTIONS outside
tools/android/loading)

[Benoit L, 2016/11/21 13:40:32]

Done.

+  args = parser.parse_args()
+  OPTIONS.SetParsedArgs(args)
+  return args
+
+
+def FindDevice(device_id):
+  """Returns a device matching |device_id| or the first one if None, or None."""
+  devices = device_utils.DeviceUtils.HealthyDevices()
+  if device_id is None:
+    return devices[0]
+  matching_devices = [d for d in devices if str(d) == device_id]
+  if not matching_devices:
+    return None
+  return matching_devices[0]
+
+
+def Setup(device, additional_flags=None):
+  """Sets up a device and returns an instance of RemoteChromeController."""
+  if not device.HasRoot():
+    device.EnableRoot()
+  chrome_controller = controller.RemoteChromeController(device)
+  device.ForceStop(OPTIONS.ChromePackage().package)
+  if additional_flags is not None:
+    chrome_controller.AddChromeArguments(additional_flags)
+  chrome_controller.ResetBrowserState()
+  return chrome_controller
+
+
+def DatabaseDevicePath():
+  return ('/data/user/0/%s/app_chrome/Default/Network Action Predictor' %
+          OPTIONS.ChromePackage().package)