Add variations combinations testing framework

tools/chrome_proxy/webdriver/variations_combinations.py

Index: tools/chrome_proxy/webdriver/variations_combinations.py
diff --git a/tools/chrome_proxy/webdriver/variations_combinations.py b/tools/chrome_proxy/webdriver/variations_combinations.py
new file mode 100644
index 0000000000000000000000000000000000000000..3471a418acd2a44887806c0aab0c0c678fadf48e
--- /dev/null
+++ b/tools/chrome_proxy/webdriver/variations_combinations.py
@@ -0,0 +1,101 @@
+# Copyright 2017 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.
+
+import os
+import re
+import sys
+import time
+import unittest
+
+import common
+
+
+combinations = [
+  # One object for each set of tests to run with the given variations.
+  {
+    'label': 'dummy example',
+    'tests': [
+      # Of the form <file_name>.<class_name>.<method_name>
+      # Also accepts wildcard (*) as matching anything.
+      "lite_page.LitePage.testLitePage",
+      "lite_page.LitePage.testLitePageFallback",
+      "quic*"
+    ],
+    'variations': [
+      "DataReductionProxyUseQuic/Enabled",
+      "DataCompressionProxyLoFi/Enabled_Preview",
+      "DataCompressionProxyLitePageFallback/Enabled"
+    ],
+    'variations-params': [
+      "DataCompressionProxyLoFi.Enabled_Preview:effective_connection_type/4G"
+    ]
+  }
+]
+
+
+def GetAllTestsFromRegexList(test_list, test_suite_iter):
+  """A helper function to make a test suite from tests matching the given list.
+
+  Args:
+    test_list: a string list of all tests to run, allowing for simple regex
+    test_suite_iter: An iterator of all test suites to search
+  Returns:
+    a test suite with all the tests specified by the test_list
+  """
+  id_to_test_map = {}
+  for test_suite in test_suite_iter:
+    for test_case in test_suite:
+      for test_method in test_case:
+        id_to_test_map[test_method.id()] = test_method
+  my_test_suite = unittest.TestSuite()
+  for test_spec in test_list:
+    regex = re.compile('^' + test_spec.replace('.', '\\.').replace('*', '.*')
+      + '$')
+    for test_id in sorted(id_to_test_map):
+      if regex.match(test_id):
+        my_test_suite.addTest(id_to_test_map[test_id])
+  return my_test_suite
+
+def ParseFlagsWithExtraBrowserArgs(extra_args):
+  """Generates a function to override common.ParseFlags.
+
+  The returned function will honor everything in the original ParseFlags(), but
+  adds on additional browser_args.
+
+  Args:
+    extra_args: The extra browser agruments to add.
+  Returns:
+    A function to override common.ParseFlags with additional browser_args.
+  """
+  original_flags = common.ParseFlags()
+  def AddExtraBrowserArgs():
+    original_flags.browser_args = ((original_flags.browser_args if
+      original_flags.browser_args else '') + ' ' + extra_args)
+    return original_flags
+  return AddExtraBrowserArgs
+
+def main():
+  """Runs each set of tests against its set of variations.
+
+  For each test combination, the above variation specifications will be used to
+  setup the browser arguments for each test given above that will be run.
+  """
+  flags = common.ParseFlags()
+  for variation_test in combinations:
+    # Set browser arguments to use the given variations.
+    extra_args = '--force-fieldtrials=' + '/'.join(variation_test['variations'])
+    extra_args += ' --force-fieldtrial-params=' + ','.join(
+      variation_test['variations-params'])
+    common.ParseFlags = ParseFlagsWithExtraBrowserArgs(extra_args)
+    # Run the given tests.
+    loader = unittest.TestLoader()
+    test_suite_iter = loader.discover(os.path.dirname(__file__), pattern='*.py')
+    my_test_suite = GetAllTestsFromRegexList(variation_test['tests'],
+      test_suite_iter)
+    testRunner = unittest.runner.TextTestRunner(verbosity=2,
+      failfast=flags.failfast, buffer=(not flags.disable_buffer))
+    testRunner.run(my_test_suite)
+
+if __name__ == '__main__':
+  main()