[Android] Redesigns the sharder to allow replicated vs distributed tests

build/android/pylib/browsertests/dispatch.py

-# Copyright (c) 2013 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.
-
-"""Dispatches content_browsertests."""
-
-import logging
-import os
-import shutil
-import sys
-
-from pylib import android_commands
-from pylib import cmd_helper
-from pylib import constants
-from pylib import ports
-from pylib.base import base_test_result
-from pylib.base import shard
-from pylib.gtest import dispatch as gtest_dispatch
-from pylib.gtest import test_runner
-from pylib.utils import report_results
-
-sys.path.insert(0,
-                os.path.join(constants.DIR_SOURCE_ROOT, 'build', 'util', 'lib'))
-from common import unittest_util
-
-
-def Dispatch(options):
-  """Dispatches all content_browsertests.
-
-  Args:
-    options: optparse.Options object containing command-line options
-  Returns:
-    A tuple of (base_test_result.TestRunResults object, exit code).
-  Raises:
-    Exception: Failed to reset the test server port.
-  """
-
-  attached_devices = []
-  if options.test_device:
-    attached_devices = [options.test_device]
-  else:
-    attached_devices = android_commands.GetAttachedDevices()
-
-  if not attached_devices:
-    logging.critical('A device must be attached and online.')
-    return (base_test_result.TestRunResults(), constants.ERROR_EXIT_CODE)
-
-  # Reset the test port allocation. It's important to do it before starting
-  # to dispatch any tests.
-  if not ports.ResetTestServerPortAllocation():
-    raise Exception('Failed to reset test server port.')
-
-  test_suite_dir = os.path.join(cmd_helper.OutDirectory.get(),
-                                options.build_type)
-  options.test_suite = os.path.join(test_suite_dir,
-                                    'apks',
-                                    constants.BROWSERTEST_SUITE_NAME + '.apk')
-
-  gtest_dispatch._GenerateDepsDirUsingIsolate(
-      constants.BROWSERTEST_SUITE_NAME, options.build_type)
-
-  # Constructs a new TestRunner with the current options.
-  def RunnerFactory(device, shard_index):
-    return test_runner.TestRunner(
-        device,
-        options.test_suite,
-        options.test_arguments,
-        options.timeout,
-        options.cleanup_test_files,
-        options.tool,
-        options.build_type,
-        options.webkit,
-        options.push_deps,
-        constants.BROWSERTEST_TEST_PACKAGE_NAME,
-        constants.BROWSERTEST_TEST_ACTIVITY_NAME,
-        constants.BROWSERTEST_COMMAND_LINE_FILE)
-
-  # Get tests and split them up based on the number of devices.
-  all_enabled = gtest_dispatch.GetAllEnabledTests(RunnerFactory,
-                                                  attached_devices)
-  if options.test_filter:
-    all_tests = unittest_util.FilterTestNames(all_enabled,
-                                              options.test_filter)
-  else:
-    all_tests = _FilterTests(all_enabled)
-
-  # Run tests.
-  # TODO(nileshagrawal): remove this abnormally long setup timeout once fewer
-  # files are pushed to the devices for content_browsertests: crbug.com/138275
-  setup_timeout = 20 * 60  # 20 minutes
-  test_results, exit_code = shard.ShardAndRunTests(
-      RunnerFactory, attached_devices, all_tests, options.build_type,
-      setup_timeout=setup_timeout, test_timeout=None,
-      num_retries=options.num_retries)
-  report_results.LogFull(
-      results=test_results,
-      test_type='Unit test',
-      test_package=constants.BROWSERTEST_SUITE_NAME,
-      build_type=options.build_type,
-      flakiness_server=options.flakiness_dashboard_server)
-
-  if os.path.isdir(constants.ISOLATE_DEPS_DIR):
-    shutil.rmtree(constants.ISOLATE_DEPS_DIR)
-
-  return (test_results, exit_code)
-
-
-def _FilterTests(all_enabled_tests):
-  """Filters out tests and fixtures starting with PRE_ and MANUAL_."""
-  return [t for t in all_enabled_tests if _ShouldRunOnBot(t)]
-
-
-def _ShouldRunOnBot(test):
-  fixture, case = test.split('.', 1)
-  if _StartsWith(fixture, case, 'PRE_'):
-    return False
-  if _StartsWith(fixture, case, 'MANUAL_'):
-    return False
-  return True
-
-
-def _StartsWith(a, b, prefix):
-  return a.startswith(prefix) or b.startswith(prefix)