Refactored bisect results dicts into a separate class

tools/auto_bisect/bisect_results_test.py

+# 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.
+
+import unittest
+
+import bisect_results
+import ttest
+
+
+class ConfidenceScoreTest(unittest.TestCase):
+
+  def testConfidenceScoreIsZeroOnTooFewLists(self):
+    self.assertEqual(bisect_results.ConfidenceScore([], [[1], [2]]), 0.0)
+    self.assertEqual(bisect_results.ConfidenceScore([[1], [2]], []), 0.0)
+    self.assertEqual(bisect_results.ConfidenceScore([[1]], [[1], [2]]), 0.0)
+    self.assertEqual(bisect_results.ConfidenceScore([[1], [2]], [[1]]), 0.0)
+
+  def testConfidenceScoreIsZeroOnEmptyLists(self):
+    self.assertEqual(bisect_results.ConfidenceScore([[], []], [[1], [2]]), 0.0)
+    self.assertEqual(bisect_results.ConfidenceScore([[1], [2]], [[], []]), 0.0)
+
+  def testConfidenceScoreIsUsingTTestWelchsTTest(self):
+    original_WelchsTTest = ttest.WelchsTTest
+    try:
+      ttest.WelchsTTest = lambda _sample1, _sample2: (0, 0, 0.42)
+      self.assertAlmostEqual(
+        bisect_results.ConfidenceScore([[1], [1]], [[2], [2]]), 58.0)
+    finally:
+      ttest.WelchsTTest = original_WelchsTTest
+
+
+class BisectResulstsTest(unittest.TestCase):
+  # TODO(sergiyb): Write tests for GetResultDicts when it is broken into smaller
+  # pieces.
+  pass
+
+
+if __name__ == '__main__':
+  unittest.main()