[Android] Converts host driven tests to common test_dispatcher

build/android/pylib/host_driven/test_runner.py

 # 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.
 
-"""Helper module for calling python-based tests."""
+"""Runs host-driven tests on a particular device."""
+
+import copy
+import logging
+import multiprocessing
+
+from pylib.base import base_test_result
+from pylib.base import base_test_runner
+from pylib.base import sharded_tests_queue
+from pylib.instrumentation import test_result
+
+import test_base
 
 
-import logging
-import sys
-import time
-import traceback
-
-from pylib.base import base_test_result
-from pylib.instrumentation import test_result
-
-
-class PythonExceptionTestResult(test_result.InstrumentationTestResult):
-  """Helper class for creating a test result from python exception."""
+class HostDrivenExceptionTestResult(test_result.InstrumentationTestResult):
+  """A test result from an exception in a host-driven test."""
 
   def __init__(self, test_name, start_date_ms, exc_info):
-    """Constructs an PythonExceptionTestResult object.
+    """Constructs an HostDrivenExceptionTestResult object.
 
     Args:
       test_name: name of the test which raised an exception.
       start_date_ms: the starting time for the test.
       exc_info: exception info, ostensibly from sys.exc_info().
     """
     exc_type, exc_value, exc_traceback = exc_info
     trace_info = ''.join(traceback.format_exception(exc_type, exc_value,
                                                     exc_traceback))
     log_msg = 'Exception:\n' + trace_info
     duration_ms = (int(time.time()) * 1000) - start_date_ms
 
-    super(PythonExceptionTestResult, self).__init__(
-        'PythonWrapper#' + test_name,
+    super(HostDrivenExceptionTestResult, self).__init__(
+        'HostDrivenWrapper#' + test_name,
         base_test_result.ResultType.FAIL,
         start_date_ms,
         duration_ms,
         log=str(exc_type) + ' ' + log_msg)
 
 
-def CallPythonTest(test, options):
-  """Invokes a test function and translates Python exceptions into test results.
+class HostDrivenTestRunner(base_test_runner.BaseTestRunner):

[frankf, 2013/07/24 01:04:55]

By deriving from BaseTestRunner, you're inheriting SetUp/TearDown which do a
bunch of stuff including killing forwarder etc. Make sure, these don't interfere
with the assumption in existing tests. You can make these a NOOP if required.

[gkanwar1, 2013/07/24 17:38:04]

Yes, I took a look at the BaseTestRunner before making this change. Currently
Setup just calls InstallTestPackage() and PushDataDeps() both of which are NOOPs
in BaseTestRunner. I think leaving this in is potentially useful if some
host-driven test type wants to override those without duplicating the setup
framework.

+  """Thin wrapper around a list of HostDrivenTestBase instances.
 
-  This method invokes SetUp()/TearDown() on the test. It is intended to be
-  resilient to exceptions in SetUp(), the test itself, and TearDown(). Any
-  Python exception means the test is marked as failed, and the test result will
-  contain information about the exception.
+  This is meant to be a long-lived object which can run multiple host-driven
+  tests within its lifetime. Tests will receive the device_id and shard_index.
 
-  If SetUp() raises an exception, the test is not run.
-
-  If TearDown() raises an exception, the test is treated as a failure. However,
-  if the test itself raised an exception beforehand, that stack trace will take
-  precedence whether or not TearDown() also raised an exception.
-
-  shard_index is not applicable in single-device scenarios, when test execution
-  is serial rather than parallel. Tests can use this to bring up servers with
-  unique port numbers, for example. See also python_test_sharder.
-
-  Args:
-    test: an object which is ostensibly a subclass of PythonTestBase.
-    options: Options to use for setting up tests.
-
-  Returns:
-    A TestRunResults object which contains any results produced by the test or,
-    in the case of a Python exception, the Python exception info.
+  The shard index affords the ability to create unique port numbers (e.g.
+  DEFAULT_PORT + shard_index) if the test so wishes.
   """
 
-  start_date_ms = int(time.time()) * 1000
-  failed = False
+  #override
+  def __init__(self, device, shard_index, tool, build_type, push_deps,
+               cleanup_test_files):
+    """Create a new HostDrivenTestRunner
 
-  try:
-    test.SetUp(options)
-  except Exception:
-    failed = True
-    logging.exception(
-        'Caught exception while trying to run SetUp() for test: ' +
-        test.qualified_name)
-    # Tests whose SetUp() method has failed are likely to fail, or at least
-    # yield invalid results.
-    exc_info = sys.exc_info()
-    results = base_test_result.TestRunResults()
-    results.AddResult(PythonExceptionTestResult(
-        test.qualified_name, start_date_ms, exc_info))
-    return results
+    Args:
+      device: Attached android device.
+      shard_index: Shard index.
+      tool: Name of the Valgrind tool.
+      build_type: 'Release' or 'Debug'.
+      push_deps: If True, push all dependencies to the device.
+      cleanup_test_files: Whether or not to cleanup test files on device.
+    """
 
-  try:
+    super(HostDrivenTestRunner, self).__init__(device, tool, build_type,
+                                               push_deps, cleanup_test_files)
+    self.shard_index = shard_index
+
+  #override
+  def RunTest(self, test):
+    """Sets up and runs a test case.
+
+    Args:
+      test: An object which is ostensibly a subclass of HostDrivenTestBase.
+
+    Returns:
+      A TestRunResults object which contains any results produced by the test
+      or, in the case of a Python exception, the Python exception info, and
+      which tests to retry or None.
+    """
+
+    assert(isinstance(test, test_base.HostDrivenTestBase))
+    test.SetUp(self.device, self.shard_index, self.build_type, self._push_deps,
+               self._cleanup_test_files)
     results = test.Run()
-  except Exception:
-    # Setting this lets TearDown() avoid stomping on our stack trace from Run()
-    # should TearDown() also raise an exception.
-    failed = True
-    logging.exception('Caught exception while trying to run test: ' +
-                      test.qualified_name)
-    exc_info = sys.exc_info()
-    results = base_test_result.TestRunResults()
-    results.AddResult(PythonExceptionTestResult(
-        test.qualified_name, start_date_ms, exc_info))
+    test.TearDown()

[frankf, 2013/07/24 01:04:55]

There's no exception handling here. Think about the failure cases.

[gkanwar1, 2013/07/24 17:38:04]

Ah, I removed the try/excepts because we're using the Reraiser thread, but I
still need to make sure exceptions in Run() let TearDown happen before raising.
Fixed.

 
-  try:
-    test.TearDown()
-  except Exception:
-    logging.exception(
-        'Caught exception while trying run TearDown() for test: ' +
-        test.qualified_name)
-    if not failed:
-      # Don't stomp the error during the test if TearDown blows up. This is a
-      # trade-off: if the test fails, this will mask any problem with TearDown
-      # until the test is fixed.
-      exc_info = sys.exc_info()
-      results = base_test_result.TestRunResults()
-      results.AddResult(PythonExceptionTestResult(
-          test.qualified_name, start_date_ms, exc_info))
-
-  return results
+    if not results.DidRunPass():
+      return results, test
+    else:
+      return results, None