Replace recipes_test.py with a new parallel expectation-based test runner.

scripts/slave/unittests/recipe_simulation_test.py

+#!/usr/bin/python
+# Copyright 2014 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.
+
+"""Provides simulator test coverage for individual recipes."""
+
+import os
+
+import test_env  # pylint: disable=unused-import

[Vadim Sh., 2014/04/01 03:00:26]

nit: from . import test_env? And same for expect_tests below.
Also, are you importing test_env for side effects? Add a comment about that.

[iannucci, 2014/04/01 03:45:14]

Can't when __name__ == __main__
Yeah, we are, that's all it's used for. Done.

+
+from common import annotator
+from slave import annotated_run
+from slave import recipe_config_types
+from slave import recipe_loader
+from slave import recipe_util
+
+import expect_tests
+
+
+def RunRecipe(test_data):
+  stream = annotator.StructuredAnnotationStream(stream=open(os.devnull, 'w'))

[Vadim Sh., 2014/04/01 03:00:26]

Does os.devnull work on windows?

[iannucci, 2014/04/01 03:45:14]

yep. It's NUL

+  recipe_config_types.ResetTostringFns()
+  # TODO(iannucci): Only pass test_data once.
+  result = annotated_run.run_steps(stream, test_data.properties,
+                                   test_data.properties, test_data)
+  return expect_tests.Result([s.step for s in result.steps_ran.itervalues()])
+
+
+def GenerateTests():
+  mods = recipe_loader.load_recipe_modules(recipe_loader.MODULE_DIRS())
+
+  for recipe_path, recipe_name in recipe_loader.loop_over_recipes():
+    recipe = recipe_loader.load_recipe(recipe_name)
+    test_api = recipe_loader.create_test_api(recipe.DEPS)
+    for test_data in recipe.GenTests(test_api):
+      root, name = os.path.split(recipe_path)
+      name = os.path.splitext(name)[0]
+      expect_path = os.path.join(root, '%s.expected' % name)
+
+      test_data.properties['recipe'] = recipe_name
+      yield expect_tests.Test(
+          '%s.%s' % (recipe_name, test_data.name),
+          RunRecipe, args=(test_data,),
+          expectdir=expect_path,
+          expectbase=test_data.name,
+          break_funcs=(mods.step.API.__call__,
+                       recipe.GenSteps)
+      )
+
+
+if __name__ == '__main__':
+  expect_tests.main(GenerateTests, (
+      [os.path.join(x, '*') for x in recipe_util.RECIPE_DIRS()] +
+      [os.path.join(x, '*', '*api.py') for x in recipe_util.MODULE_DIRS()]

[iannucci, 2014/04/01 01:43:53]

Note that this should really be '*.py', but that actually reveals a couple
uncovered lines of code *gasp*, so carrying this over from the previous tests.

+  ), (
+      [os.path.join(x, '*', '*config.py') for x in recipe_util.MODULE_DIRS()]
+  ))