webrtc: use correct cwd for running tests

scripts/slave/recipe_modules/webrtc/api.py

 # Copyright 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.
 
 from recipe_engine.types import freeze
 from recipe_engine import recipe_api
 from . import builders
 from . import steps
 
 
 class WebRTCApi(recipe_api.RecipeApi):
   def __init__(self, **kwargs):
     super(WebRTCApi, self).__init__(**kwargs)
     self._env = {}
 
+    # Keep track of working directory (which contains the checkout).
+    # None means "default value".
+    self._working_dir = None
+
   BUILDERS = builders.BUILDERS
   RECIPE_CONFIGS = builders.RECIPE_CONFIGS
 
   NORMAL_TESTS = (
     'audio_decoder_unittests',
     'common_audio_unittests',
     'common_video_unittests',
     'modules_tests',
     'modules_unittests',
     'peerconnection_unittests',
@@ skipping 105 matching lines @@
       self.m.chromium_swarming.configure_swarming(
           'webrtc',
           precommit=self.m.tryserver.is_tryserver,
           mastername=mastername)
       self.m.swarming.set_default_dimension(
           'os',
           self.m.swarming.prefered_os_dimension(
               self.m.platform.name).split('-', 1)[0])
 
   def checkout(self, **kwargs):
-    checkout_dir = self.m.chromium_tests.get_checkout_dir({})
-    if checkout_dir:
-      kwargs.setdefault('cwd', checkout_dir)
+    self._working_dir = self.m.chromium_tests.get_checkout_dir({})
+    if self._working_dir:
+      kwargs.setdefault('cwd', self._working_dir)
 
     update_step = self.m.bot_update.ensure_checkout(**kwargs)
     assert update_step.json.output['did_run']
 
     # Whatever step is run right before this line needs to emit got_revision.
     revs = update_step.presentation.properties
     self.revision = revs['got_revision']
     self.revision_cp = revs['got_revision_cp']
     self.revision_number = str(self.m.commit_position.parse_revision(
         self.revision_cp))
@@ skipping 16 matching lines @@
       self.m.chromium.run_gn(use_goma=True)
 
     self.m.chromium.compile()
 
   def runtests(self):
     """Add a suite of test steps.
 
     Args:
       test_suite: The name of the test suite.
     """
-    if self.c.use_isolate:
-      self.m.isolate.remove_build_metadata()
-      self.m.isolate.isolate_tests(self.m.chromium.output_dir,
-                                   targets=self.NORMAL_TESTS)
+    context = {}
+    if self._working_dir:
+      context['cwd'] = self._working_dir
 
-    tests = steps.generate_tests(self, self.c.TEST_SUITE, self.revision,
-                                 self.c.enable_swarming)
-    with self.m.step.defer_results():
-      if tests:
-        if self.m.chromium.c.TARGET_PLATFORM == 'android':
-          self.m.chromium_android.common_tests_setup_steps()
+    with self.m.step.context(context):
+      if self.c.use_isolate:
+        self.m.isolate.remove_build_metadata()
+        self.m.isolate.isolate_tests(self.m.chromium.output_dir,
+                                     targets=self.NORMAL_TESTS)
 
+      tests = steps.generate_tests(self, self.c.TEST_SUITE, self.revision,
+                                   self.c.enable_swarming)
+      with self.m.step.defer_results():
+        if tests:
+          if self.m.chromium.c.TARGET_PLATFORM == 'android':
+            self.m.chromium_android.common_tests_setup_steps()
+
+          for test in tests:
+            test.run(self, suffix='')
+
+          if self.m.chromium.c.TARGET_PLATFORM == 'android':
+            self.m.chromium_android.shutdown_device_monitor()
+            self.m.chromium_android.logcat_dump(gs_bucket='chromium-android')
+            self.m.chromium_android.stack_tool_steps(force_latest_version=True)
+            self.m.chromium_android.test_report()
+
+      with self.m.step.defer_results():
         for test in tests:
-          test.run(self, suffix='')
-
-        if self.m.chromium.c.TARGET_PLATFORM == 'android':
-          self.m.chromium_android.shutdown_device_monitor()
-          self.m.chromium_android.logcat_dump(gs_bucket='chromium-android')
-          self.m.chromium_android.stack_tool_steps(force_latest_version=True)
-          self.m.chromium_android.test_report()
-
-    with self.m.step.defer_results():
-      for test in tests:
-        if test.enable_swarming:
-          self.m.swarming.collect_task(test.swarming_task)
+          if test.enable_swarming:
+            self.m.swarming.collect_task(test.swarming_task)
 
 
   def add_test(self, test, name=None, args=None, revision=None, env=None,
                python_mode=False, perf_test=False, perf_dashboard_id=None,
                parallel=True):
     """Helper function to invoke chromium.runtest().
 
     Notice that the name parameter should be the same as the test executable in
     order to get the stdio links in the perf dashboard to become correct.
     """
@@ skipping 91 matching lines @@
   def clean_test_output(self):
     """Remove all test output in out/, since we have tests leaking files."""
     out_dir = self.m.path['checkout'].join('out')
     self.m.python('clean test output files',
                   script=self.resource('cleanup_files.py'),
                   args=[out_dir],
                   infra_step=True)
 
   def virtual_webcam_check(self):
     self.m.python('webcam_check', self.resource('ensure_webcam_is_running.py'))