add unittest for render_pictures binary

tools/tests/render_pictures_test.py

+#!/usr/bin/python
+
+"""
+Copyright 2014 Google Inc.
+
+Use of this source code is governed by a BSD-style license that can be
+found in the LICENSE file.
+
+Test the render_pictures binary.
+
+TODO(epoger): Combine with overlapping tools/test_rendering.py and
+tools/test_pictures.py .
+See https://code.google.com/p/skia/issues/detail?id=1943#c2
+"""
+
+# System-level imports
+import json
+import os
+import shutil
+import tempfile
+
+# Imports from within Skia
+import base_unittest
+
+
+class RenderPicturesTest(base_unittest.TestCase):
+
+  # Setup and teardown...

[rmistry, 2014/01/06 18:54:44]

Do not need this comment.

[epoger, 2014/01/06 20:46:13]

Removed.  I like having the sections delineated, but I guess tastes vary.

+
+  def setUp(self):
+    self._temp_dir = tempfile.mkdtemp()
+
+  def tearDown(self):
+    shutil.rmtree(self._temp_dir)
+
+  # Individual test cases...

[rmistry, 2014/01/06 18:54:44]

Do not need this comment since it is obvious from the names test_*

[epoger, 2014/01/06 20:46:13]

Done.

+
+  def test_whole_image_no_comparison(self):
+    """Run render_pictures with --writeWholeImage flag."""
+    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,
+                               '--writeWholeImage'])
+    expected_summary_dict = {
+        "actual-results" : {
+            "no-comparison" : {
+                "input.png" : [ "bitmap-64bitMD5", 12793741875005523433 ]

[epoger, 2014/01/03 21:46:12]

I have not validated that this checksum is actually correct for the SKP we are
rendering (a 640x400 red rectangle).  But if we do a spot check of the
render_pictures output, and the unittest results remain consistent over time,
that should keep our tools in working order.

+                }
+            }
+        }
+    self._assert_json_contents(output_json_path, expected_summary_dict)
+
+  def test_tiles_no_comparison(self):
+    """Generate individual tiles.
+
+    TODO(epoger): The results of this test are currently broken!

[epoger, 2014/01/03 21:46:12]

I was surprised to see the results of this test!  Definitely worth more
investigation, but I'd like to get the unittests checked in as soon as possible
anyway.

+    The summary should contain a list of tiles, but for some reason, it is
+    empty."""
+    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)
+
+  # Helper functions...

[rmistry, 2014/01/06 18:54:44]

Do not need this comment as well.

[epoger, 2014/01/06 20:46:13]

Done.

+
+  def _run_render_pictures(self, args):
+    binary = self.find_path_to_program('render_pictures')
+    return self.run_command([binary,
+                             '--bbh', 'grid', '256', '256',
+                             '--clone', '1',
+                             '--config', '8888',
+                             '--mode', 'tile', '256', '256',

[rmistry, 2014/01/06 18:54:44]

It might also be worth doing a test with render_pictures args without '--bbh
grid 256 256' and '--mode tile 256 256' i.e. whole image test without
--writeWholeImage. WDYT?

[epoger, 2014/01/06 20:46:13]

Sure, good idea.  Note that it gives unexpected results, too, which I will
address as soon as this CL lands.

+                             '--validate'
+                             ] + args)
+
+  def _run_skpmaker(self, args):
+    binary = self.find_path_to_program('skpmaker')
+    return self.run_command([binary,
+                             '--red', '255',
+                             '--green', '0',
+                             '--blue', '0',
+                             '--width', '640',
+                             '--height', '400',
+                             ] + args)
+
+  def _assert_json_contents(self, json_path, expected_dict):
+    """Asserts that contents of a JSON file are identical to expected_dict.
+
+    Args:
+      json_path: Path to a JSON file.
+      expected_dict: Dictionary indicating the expected contents of the JSON
+                     file.
+
+    Raises:
+      AssertionError: contents of the JSON file are not identical to
+                      expected_dict.
+    """
+    file_contents = open(json_path, 'r').read()
+    actual_dict = json.loads(file_contents)
+    self.assertEqual(actual_dict, expected_dict)
+
+
+def main():
+  base_unittest.main(RenderPicturesTest)
+
+
+if __name__ == '__main__':
+  main()