Always use html_diff to generate -pretty-diff.html files.

The idea of this patch is to start using html_diff for -pretty-diff.html
files; once these files are always available then the wdiff-related code
can be removed and there will still be some kind of HTML diff on Windows.

In order to keep this change minimal, the files are still called
-pretty-diff.html and "has_pretty_patch" is still set in the results JSON,
but after this, the "has_pretty_patch" and "has_wdiff" keys in the results
JSON should be removed.

BUG=672651

Review-Url: https://codereview.chromium.org/2580343003
Cr-Commit-Position: refs/heads/master@{#440765}

third_party/WebKit/Tools/Scripts/webkitpy/layout_tests/controllers/test_result_writer.py

@@ -29,6 +29,7 @@
 
 import logging
 
+from webkitpy.common.html_diff import html_diff
 from webkitpy.layout_tests.controllers import repaint_overlay
 from webkitpy.layout_tests.models import test_failures
 
@@ -113,7 +114,7 @@ class TestResultWriter(object):
     FILENAME_SUFFIX_SAMPLE = "-sample"
     FILENAME_SUFFIX_LEAK_LOG = "-leak-log"
     FILENAME_SUFFIX_WDIFF = "-wdiff.html"
-    FILENAME_SUFFIX_PRETTY_PATCH = "-pretty-diff.html"
+    FILENAME_SUFFIX_HTML_DIFF = "-pretty-diff.html"
     FILENAME_SUFFIX_IMAGE_DIFF = "-diff.png"
     FILENAME_SUFFIX_IMAGE_DIFFS_HTML = "-diffs.html"
     FILENAME_SUFFIX_OVERLAY = "-overlay.html"
@@ -199,11 +200,10 @@ class TestResultWriter(object):
         if not actual_text or not expected_text:
             return
 
+        # Output a plain-text diff file.
         file_type = '.txt'
         actual_filename = self.output_filename(self.FILENAME_SUFFIX_ACTUAL + file_type)
         expected_filename = self.output_filename(self.FILENAME_SUFFIX_EXPECTED + file_type)
-        # We treat diff output as binary. Diff output may contain multiple files
-        # in conflicting encodings.
         diff = self._port.diff_text(expected_text, actual_text, expected_filename, actual_filename)
         diff_filename = self.output_filename(self.FILENAME_SUFFIX_DIFF + file_type)
         self._write_file(diff_filename, diff)
@@ -214,11 +214,10 @@ class TestResultWriter(object):
             wdiff_filename = self.output_filename(self.FILENAME_SUFFIX_WDIFF)
             self._write_file(wdiff_filename, wdiff)
 
-        # Use WebKit's PrettyPatch.rb to get an HTML diff.
-        if self._port.pretty_patch_available():
-            pretty_patch = self._port.pretty_patch_text(diff_filename)
-            pretty_patch_filename = self.output_filename(self.FILENAME_SUFFIX_PRETTY_PATCH)
-            self._write_file(pretty_patch_filename, pretty_patch)
+        # Output a HTML diff file.
+        html_diff_filename = self.output_filename(self.FILENAME_SUFFIX_HTML_DIFF)
+        html_diff_contents = html_diff(expected_text, actual_text)
+        self._write_file(html_diff_filename, html_diff_contents)
 
     def create_repaint_overlay_result(self, actual_text, expected_text):
         html = repaint_overlay.generate_repaint_overlay_html(self._test_name, actual_text, expected_text)

third_party/WebKit/Tools/Scripts/webkitpy/layout_tests/models/test_run_results.py

@@ -329,7 +329,7 @@ def summarize_results(port_obj, expectations, initial_results,
     results['interrupted'] = initial_results.interrupted
     results['layout_tests_dir'] = port_obj.layout_tests_dir()
     results['has_wdiff'] = port_obj.wdiff_available()
-    results['has_pretty_patch'] = port_obj.pretty_patch_available()
+    results['has_pretty_patch'] = True
     results['pixel_tests_enabled'] = port_obj.get_option('pixel_tests')
     results['seconds_since_epoch'] = int(time.time())
     results['build_number'] = port_obj.get_option('build_number')
@@ -337,6 +337,9 @@ def summarize_results(port_obj, expectations, initial_results,
     if port_obj.get_option('order') == 'random':
         results['random_order_seed'] = port_obj.get_option('seed')
     results['path_delimiter'] = '/'
+    # The pretty-diff.html files should always be available.
+    # TODO(qyearsley): Change this key since PrettyPatch.rb has been removed.
+    results['has_pretty_patch'] = True
 
     # Don't do this by default since it takes >100ms.
     # It's only used for rebaselining and uploading data to the flakiness dashboard.

third_party/WebKit/Tools/Scripts/webkitpy/layout_tests/run_webkit_tests_unittest.py

@@ -967,19 +967,19 @@ class RunTest(unittest.TestCase, StreamTestingMixin):
         self.assertNotIn('platform/test-win-win7/http/test.html', tests_run)
 
     def test_output_diffs(self):
-        # Test to ensure that we don't generate -wdiff.html or -pretty.html if wdiff and PrettyPatch
-        # aren't available.
+        # Test to ensure that we don't generate -wdiff.html if wdiff isn't available,
+        # but we always generate -diff.txt an -pretty-diff.html.
         host = MockHost()
         logging_run(['--pixel-tests', 'failures/unexpected/text-image-checksum.html'], tests_included=True, host=host)
         written_files = host.filesystem.written_files
-        self.assertTrue(any(path.endswith('-diff.txt') for path in written_files.keys()))
-        self.assertFalse(any(path.endswith('-wdiff.html') for path in written_files.keys()))
-        self.assertFalse(any(path.endswith('-pretty-diff.html') for path in written_files.keys()))
+        self.assertTrue(any(path.endswith('-diff.txt') for path in written_files))
+        self.assertTrue(any(path.endswith('-pretty-diff.html') for path in written_files))
+        self.assertFalse(any(path.endswith('-wdiff.html') for path in written_files))
 
         full_results_text = host.filesystem.read_text_file('/tmp/layout-test-results/full_results.json')
         full_results = json.loads(full_results_text.replace("ADD_RESULTS(", "").replace(");", ""))
         self.assertEqual(full_results['has_wdiff'], False)
-        self.assertEqual(full_results['has_pretty_patch'], False)
+        self.assertEqual(full_results['has_pretty_patch'], True)
 
     def test_unsupported_platform(self):
         stdout = StringIO.StringIO()