render_pictures: adjust unittests to show specific failures

tools/tests/render_pictures_test.py

Index: tools/tests/render_pictures_test.py
diff --git a/tools/tests/render_pictures_test.py b/tools/tests/render_pictures_test.py
index 33c1e6a0469c8d70bf4fffe748c2a0ebb70da19f..608df9fdbc044878172ba548126575477f84be0c 100755
--- a/tools/tests/render_pictures_test.py
+++ b/tools/tests/render_pictures_test.py
@@ -18,11 +18,15 @@ import tempfile
 # Imports from within Skia
 import base_unittest
 
+# Maximum length of text diffs to show when tests fail
+MAX_DIFF_LENGTH = 30000
+
 
 class RenderPicturesTest(base_unittest.TestCase):
 
   def setUp(self):
     self._temp_dir = tempfile.mkdtemp()
+    self.maxDiff = MAX_DIFF_LENGTH
 
   def tearDown(self):
     shutil.rmtree(self._temp_dir)
@@ -40,49 +44,93 @@ class RenderPicturesTest(base_unittest.TestCase):
     expected_summary_dict = {
         "actual-results" : {
             "no-comparison" : {
-                # Manually verified: 640x400 red image with black border
+                # Manually verified: 640x400 red rectangle with black border
                 "input.png" : [ "bitmap-64bitMD5", 11092453015575919668 ]
             }
         }
     }
     self._assert_json_contents(output_json_path, expected_summary_dict)
 
-  def test_tiled_no_comparison(self):
-    """Generate individual tiles.
-
-    TODO(epoger): The results of this test are currently broken!
-    The summary should contain a list of tiles, but for some reason, it is
-    empty."""
+  def test_untiled_no_comparison(self):
+    """Run without tiles."""
     input_skp_path = os.path.join(self._temp_dir, 'input.skp')
     output_json_path = os.path.join(self._temp_dir, 'output.json')
     self._run_skpmaker(['--writePath', input_skp_path])
     self._run_render_pictures(['-r', input_skp_path,
-                               '--bbh', 'grid', '256', '256',
-                               '--mode', 'tile', '256', '256',
+                               '--writePath', self._temp_dir,
                                '--writeJsonSummaryPath', output_json_path])
     expected_summary_dict = {
         "actual-results" : {
-            "no-comparison" : None
+            "no-comparison" : {
+                # Manually verified: 640x400 red rectangle with black border
+                "input.png" : ["bitmap-64bitMD5", 11092453015575919668],
             }
         }
+    }
     self._assert_json_contents(output_json_path, expected_summary_dict)
 
-  def test_untiled_no_comparison(self):
-    """Run without tiles.
+  def test_validate(self):
+    """Same as test_untiled_no_comparison, but with --validate.
+
+    TODO(epoger): This test generates undesired results!  The call
+    to render_pictures should succeed, and generate the same output as
+    test_untiled_no_comparison.
+    See https://code.google.com/p/skia/issues/detail?id=2044 ('render_pictures:
+    --validate fails')
+    """
+    input_skp_path = os.path.join(self._temp_dir, 'input.skp')
+    output_json_path = os.path.join(self._temp_dir, 'output.json')
+    self._run_skpmaker(['--writePath', input_skp_path])
+    with self.assertRaises(Exception):
+      self._run_render_pictures(['-r', input_skp_path,
+                                 '--validate',
+                                 '--writePath', self._temp_dir,
+                                 '--writeJsonSummaryPath', output_json_path])
+
+  def test_without_writePath(self):
+    """Same as test_untiled_no_comparison, but without --writePath.
+
+    TODO(epoger): This test generates undesired results!
+    See https://code.google.com/p/skia/issues/detail?id=2043 ('render_pictures:
+    --writeJsonSummaryPath fails unless --writePath is specified')
+    """
+    input_skp_path = os.path.join(self._temp_dir, 'input.skp')
+    output_json_path = os.path.join(self._temp_dir, 'output.json')
+    self._run_skpmaker(['--writePath', input_skp_path])
+    self._run_render_pictures(['-r', input_skp_path,
+                               '--writeJsonSummaryPath', output_json_path])
+    expected_summary_dict = {
+        "actual-results" : {
+            "no-comparison" : None,
+        }
+    }
+    self._assert_json_contents(output_json_path, expected_summary_dict)
 
-    TODO(epoger): The results of this test are currently broken!
-    The summary should contain a single image, but for some reason, it is
-    empty."""
+  def test_tiled_no_comparison(self):
+    """Generate individual tiles."""
     input_skp_path = os.path.join(self._temp_dir, 'input.skp')
     output_json_path = os.path.join(self._temp_dir, 'output.json')
     self._run_skpmaker(['--writePath', input_skp_path])
     self._run_render_pictures(['-r', input_skp_path,
+                               '--bbh', 'grid', '256', '256',
+                               '--mode', 'tile', '256', '256',
+                               '--writePath', self._temp_dir,
                                '--writeJsonSummaryPath', output_json_path])
     expected_summary_dict = {
         "actual-results" : {
-            "no-comparison" : None
+            "no-comparison" : {
+                # Manually verified these 6 images, all 256x256 tiles,
+                # consistent with a tiled version of the 640x400 red rect
+                # with black borders.
+                "input0.png" : ["bitmap-64bitMD5", 5815827069051002745],
+                "input1.png" : ["bitmap-64bitMD5", 9323613075234140270],
+                "input2.png" : ["bitmap-64bitMD5", 16670399404877552232],
+                "input3.png" : ["bitmap-64bitMD5", 2507897274083364964],
+                "input4.png" : ["bitmap-64bitMD5", 7325267995523877959],
+                "input5.png" : ["bitmap-64bitMD5", 2181381724594493116],
             }
         }
+    }
     self._assert_json_contents(output_json_path, expected_summary_dict)
 
   def _run_render_pictures(self, args):
@@ -90,7 +138,6 @@ class RenderPicturesTest(base_unittest.TestCase):
     return self.run_command([binary,
                              '--clone', '1',
                              '--config', '8888',
-                             '--validate'
                              ] + args)
 
   def _run_skpmaker(self, args):