[Findit] Fixing analysis mismatch in check flake

appengine/findit/model/flake/test/master_flake_analysis_test.py

 # Copyright 2016 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 datetime import datetime
 
 import unittest
 
 from model import analysis_status
 from model import result_status
@@ skipping 119 matching lines @@
 
   def testGetIterationsToRerun(self):
     cases = [
         (-1, {}),
         (5, {'key': 'value', 'iterations_to_rerun': 5}),
     ]
     for expected_rerun, algorithm_parameters in cases:
       analysis = MasterFlakeAnalysis.Create('m', 'b', 123, 's', 't')
       analysis.algorithm_parameters = algorithm_parameters
       self.assertEqual(expected_rerun, analysis.iterations_to_rerun)
+
+  def testGetBuildConfigurationFromKey(self):
+    master_name = 'm'
+    builder_name = 'b'
+    build_number = 123
+    step_name = 's'
+    test_name = 't'
+
+    key = MasterFlakeAnalysis.Create(
+        master_name, builder_name, build_number, step_name, test_name).key
+
+    self.assertEqual(
+        (None, None),
+        MasterFlakeAnalysis.GetBuildConfigurationFromKey(None))
+    self.assertEqual(
+        (master_name, builder_name),
+        MasterFlakeAnalysis.GetBuildConfigurationFromKey(key))