Swarming: conditionally run tests on swarming in chromium_trybot recipe.

scripts/slave/recipe_modules/test_utils/api.py

Index: scripts/slave/recipe_modules/test_utils/api.py
diff --git a/scripts/slave/recipe_modules/test_utils/api.py b/scripts/slave/recipe_modules/test_utils/api.py
index a91b801feb820c1bbfeac33cb411ff90788e3e52..012e3f748980e9e23069d44ab2eb76aad7a7843a 100644
--- a/scripts/slave/recipe_modules/test_utils/api.py
+++ b/scripts/slave/recipe_modules/test_utils/api.py
@@ -40,6 +40,8 @@ class TestUtilsApi(recipe_api.RecipeApi):
     Base class for tests that can be retried after deapplying a previously
     applied patch.
     """
+    # If True, 'trigger' and 'collect' should be used instead of 'run'.

[M-A Ruel, 2014/06/04 00:52:53]

If I were another reader that didn't know about swarming, I'd be confused by
this comment. Either make the comment clearer or the variable name clearer of
the specificity about swarming.

[Vadim Sh., 2014/06/04 02:58:26]

Added more explanation, mentioned swarming.

+    async = False
 
     @property
     def name(self):  # pragma: no cover
@@ -50,6 +52,14 @@ class TestUtilsApi(recipe_api.RecipeApi):
       """Run the test. suffix is 'with patch' or 'without patch'."""
       raise NotImplementedError()
 
+    def trigger(self, suffix):  # pragma: no cover
+      """Launch the test asynchronously, used if self.async == True."""
+      raise NotImplementedError()
+
+    def collect(self, suffix):  # pragma: no cover
+      """Wait for triggered test to finish, used if self.async == True."""
+      raise NotImplementedError()
+
     def has_valid_results(self, suffix):  # pragma: no cover
       """
       Returns True if results (failures) are valid.
@@ -79,6 +89,9 @@ class TestUtilsApi(recipe_api.RecipeApi):
       deapply_patch_fn - function that takes a list of failing tests
                          and undoes any effect of the previously applied patch
     """
+    # Convert iterable to list, since it is enumerated multiple times.
+    tests = list(tests)
+
     if self.m.step_history.failed:
       yield self.m.python.inline(
         'Aborting due to failed build state.',
@@ -86,7 +99,17 @@ class TestUtilsApi(recipe_api.RecipeApi):
         always_run=True, abort_on_failure=True)
       return  # won't actually hit this, but be explicit
 
-    yield (t.run('with patch') for t in tests)
+    def run(prefix, tests):
+      """Runs synchronous and asynchronous tests."""

[M-A Ruel, 2014/06/04 00:52:53]

Add a note about how test can run magically in parallel.

[Vadim Sh., 2014/06/04 02:58:26]

Done.

+      # Trigger all async tests first, so that they are running in parallel
+      # with synchronous tests.
+      yield (t.trigger(prefix) for t in tests if t.async)
+      # Now block on all synchronous tests.
+      yield (t.run(prefix) for t in tests if not t.async)
+      # And finally wait for all pending asynchronous tests to complete.
+      yield (t.collect(prefix) for t in tests if t.async)
+
+    yield run('with patch', tests)
 
     failing_tests = []
     for t in tests:
@@ -106,7 +129,7 @@ class TestUtilsApi(recipe_api.RecipeApi):
 
     yield deapply_patch_fn(failing_tests)
 
-    yield (t.run('without patch') for t in failing_tests)
+    yield run('without patch', failing_tests)
     yield (self._summarize_retried_test(t) for t in failing_tests)
 
   def _summarize_retried_test(self, test):