rebaseline_server: add ImagePair class, a step towards new intermediate JSON schema

gm/rebaseline_server/imagediffdb_test.py

 #!/usr/bin/python
 
 """
 Copyright 2013 Google Inc.
 
 Use of this source code is governed by a BSD-style license that can be
 found in the LICENSE file.
 
 Test imagediffdb.py
 """
 
 # System-level imports
 import logging
 import shutil
 import tempfile
 import unittest
 
 # Local imports
 import imagediffdb
 
 
 IMG_URL_BASE = 'http://chromium-skia-gm.commondatastorage.googleapis.com/gm/bitmap-64bitMD5/'
 
 
 class ImageDiffDbTest(unittest.TestCase):
 
   def setUp(self):
     self._temp_dir = tempfile.mkdtemp()
+    self.maxDiff = None
 
   def tearDown(self):
     shutil.rmtree(self._temp_dir)
 
   def shortDescription(self):
     """Tell unittest framework to not print docstrings for test cases."""
     return None
 
+  def test_sanitize_locator(self):
+    """Test _sanitize_locator()."""
+    self.assertEqual(imagediffdb._sanitize_locator('simple'), 'simple')
+    self.assertEqual(imagediffdb._sanitize_locator(1234), '1234')
+    self.assertEqual(imagediffdb._sanitize_locator('one/two'),  'one_two')
+    self.assertEqual(imagediffdb._sanitize_locator('one\\two'), 'one_two')
+    self.assertEqual(imagediffdb._sanitize_locator('one_two'),  'one_two')
+
   def test_simple(self):
+    """Test ImageDiffDB, downloading real known images from Google Storage.
+
+    TODO(epoger): Instead of hitting Google Storage, we should read image
+    files from local disk using a file:// IMG_URL_BASE.
+    """
     # params for each self-test:
     # 0. expected image locator
     # 1. expected image URL
     # 2. actual image locator
     # 3. actual image URL
     # 4. expected percent_pixels_differing (as a string, to 4 decimal places)
     # 5. expected weighted_diff_measure (as a string, to 4 decimal places)
     # 6. expected max_diff_per_channel
     selftests = [
         [
-            '16206093933823793653',
+            'arcofzorro/16206093933823793653',
             IMG_URL_BASE + 'arcofzorro/16206093933823793653.png',
-            '13786535001616823825',
+            'arcofzorro/13786535001616823825',
             IMG_URL_BASE + 'arcofzorro/13786535001616823825.png',
             '0.0662', '0.0113', [255, 255, 247],
         ],
         [
-            '10552995703607727960',
+            'gradients_degenerate_2pt/10552995703607727960',
             IMG_URL_BASE + 'gradients_degenerate_2pt/10552995703607727960.png',
-            '11198253335583713230',
+            'gradients_degenerate_2pt/11198253335583713230',
             IMG_URL_BASE + 'gradients_degenerate_2pt/11198253335583713230.png',
             '100.0000', '66.6667', [255, 0, 255],
         ],
     ]
 
     # Add all image pairs to the database
     db = imagediffdb.ImageDiffDB(self._temp_dir)
     for selftest in selftests:
       retval = db.add_image_pair(
           expected_image_locator=selftest[0], expected_image_url=selftest[1],
           actual_image_locator=selftest[2],   actual_image_url=selftest[3])
 
     # Fetch each image pair from the database
     for selftest in selftests:
       record = db.get_diff_record(expected_image_locator=selftest[0],
                                   actual_image_locator=selftest[2])
       self.assertEqual('%.4f' % record.get_percent_pixels_differing(),
                        selftest[4])
       self.assertEqual('%.4f' % record.get_weighted_diff_measure(), selftest[5])
       self.assertEqual(record.get_max_diff_per_channel(), selftest[6])
 
 
 def main():
   suite = unittest.TestLoader().loadTestsFromTestCase(ImageDiffDbTest)
   unittest.TextTestRunner(verbosity=2).run(suite)
 
 
 if __name__ == '__main__':
   main()