Parameters to significantly_different.py need to be parsed as lists.

scripts/slave/recipe_modules/auto_bisect/resources/significantly_different_test.py

 #!/usr/bin/env python
 """Tests for significantly_different."""
 
+import json
 import os
 import sys
 import unittest
 
 # pylint: disable=relative-import
 import significantly_different
 
 
 class SignificantlyDifferentTest(unittest.TestCase):
 
   def setUp(self):
     self.conda_path = None
     try:
       import scipy  # pylint: disable=unused-variable
       self.conda_path = sys.executable
     except ImportError:
       if os.path.exists(os.path.expanduser('~/conda-test/bin/python')):
         self.conda_path = os.path.expanduser('~/conda-test/bin/python')
 
   def test_basic_case(self):
     try:
+      sample_A = [1, 2, 3, 3, 2, 1]
+      sample_B = [1, 2, 2, 2, 5, 0]
       results = significantly_different.main(
-          ['', '[1, 2, 3, 3, 2, 1]', '[1, 2, 2, 2, 5, 0]', '0.05'],
+          ['', json.dumps(sample_A), json.dumps(sample_B), '0.05'],
           self.conda_path)
     except significantly_different.ScipyNotInstalledError:
       # This is meant to let presubmit pass on CQ bots :( because they don't
       # have scipy either directly or thorugh anaconda.
       return
 
     self.assertAlmostEqual(
         0.40073980338363635,
         results['mann_p_value'])
+    self.assertEqual(results['first_sample'], sample_A)
+    self.assertEqual(results['second_sample'], sample_B)
+
+  def test_single_value(self):
+    try:
+      sample_A = [1, 1, 1, 1, 1, 1]
+      sample_B = [1, 1, 1]
+      results = significantly_different.main(
+          ['', json.dumps(sample_A), json.dumps(sample_B), '0.05'],
+          self.conda_path)
+    except significantly_different.ScipyNotInstalledError:
+      # This is meant to let presubmit pass on CQ bots :( because they don't
+      # have scipy either directly or thorugh anaconda.
+      return
+    self.assertIsNone(results['mann_p_value'])
+    self.assertFalse(results['significantly_different'])
+    self.assertEqual(results['first_sample'], sample_A)
+    self.assertEqual(results['second_sample'], sample_B)
 
 if __name__ == '__main__':
   unittest.main()