In update_w3c_test_expectations use ExpectationLine.tokenize_line and refactor.

third_party/WebKit/Tools/Scripts/webkitpy/w3c/update_w3c_test_expectations.py

 # Copyright 2016 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """A class for updating layout test expectations when updating w3c tests.
 
 Specifically, this class fetches results from try bots for the current CL, and:
   1. Downloads new baseline files for any tests that can be rebaselined.
   2. Updates the generic TestExpectations file for any other failing tests.
 
 This is used as part of the w3c test auto-import process.
 """
 
 import argparse
 import logging
 
 from webkitpy.common.net.git_cl import GitCL
 from webkitpy.common.net.rietveld import Rietveld
 from webkitpy.common.webkit_finder import WebKitFinder
 from webkitpy.w3c.test_parser import TestParser
+from webkitpy.layout_tests.models.test_expectations import TestExpectationLine
 
 _log = logging.getLogger(__name__)
 
 
 class W3CExpectationsLineAdder(object):
 
     def __init__(self, host):
         self.host = host
         self.host.initialize_scm()
         self.finder = WebKitFinder(self.host.filesystem)
@@ skipping 218 matching lines @@
                         platform_list.append(platform)
                     bug.append(platform_results[platform]['bug'])
                     expectations = self.get_expectations(platform_results[platform])
                     line = '%s [ %s ] %s [ %s ]' % (bug[0], ' '.join(platform_list), test_name, ' '.join(expectations))
                     line_list.append(str(line))
         return line_list
 
     def write_to_test_expectations(self, line_list):
         """Writes to TestExpectations.
 
-        Writes the test expectations lines in |line_list| to the test
-        expectations file.
-
         The place in the file where the new lines are inserted is after a
         marker comment line. If this marker comment line is not found, it will
         be added to the end of the file.
 
         Args:
-            line_list: A list of w3c test expectations lines.
+            line_list: A list of lines to add to the TestExpectations file.
         """
         _log.debug('Lines to write to TestExpectations: %r', line_list)
         port = self.host.port_factory.get()
-        expectations_file = port.path_to_generic_test_expectations_file()
-        comment_line = '# Tests added from W3C auto import bot'
-        file_contents = self.host.filesystem.read_text_file(expectations_file)
-        w3c_comment_line_index = file_contents.find(comment_line)
-        all_lines = ''
-        for line in line_list:
-            end_bracket_index = line.split().index(']')
-            test_name = line.split()[end_bracket_index + 1]
-            if test_name in file_contents:
-                continue
-            all_lines += str(line) + '\n'
-        all_lines = all_lines[:-1]
-        if w3c_comment_line_index == -1:
-            file_contents += '\n%s\n' % comment_line
-            file_contents += all_lines
+        expectations_file_path = port.path_to_generic_test_expectations_file()
+        marker_comment = '# Tests added from W3C auto import bot'
+        file_contents = self.host.filesystem.read_text_file(expectations_file_path)
+        marker_comment_index = file_contents.find(marker_comment)
+        line_list = [line for line in line_list if self._test_name_from_expectation_string(line) not in file_contents]
+        if marker_comment_index == -1:
+            file_contents += '\n%s\n' % marker_comment
+            file_contents += '\n'.join(line_list)
         else:
-            end_of_comment_line = (file_contents[w3c_comment_line_index:].find('\n')) + w3c_comment_line_index
-            new_data = file_contents[: end_of_comment_line + 1] + all_lines + file_contents[end_of_comment_line:]
-            file_contents = new_data
-        self.host.filesystem.write_text_file(expectations_file, file_contents)
+            end_of_marker_line = (file_contents[marker_comment_index:].find('\n')) + marker_comment_index
+            file_contents = file_contents[:end_of_marker_line + 1] + '\n'.join(line_list) + file_contents[end_of_marker_line:]
+        self.host.filesystem.write_text_file(expectations_file_path, file_contents)
+
+    @staticmethod
+    def _test_name_from_expectation_string(expectation_string):
+        return TestExpectationLine.tokenize_line(filename='', expectation_string=expectation_string, line_number=0).name
 
     def get_expected_txt_files(self, tests_results):
         """Fetches new baseline files for tests that should be rebaselined.
 
         Invokes webkit-patch rebaseline-from-try-jobs in order to download new
         -expected.txt files for testharness.js tests that did not crash or time
         out. Then, the platform-specific test is removed from the overall
         failure test dictionary.
 
         Args:
@@ skipping 55 matching lines @@
 
         Args:
             test_path: A file path relative to the layout tests directory.
                 This might correspond to a deleted file or a non-test.
         """
         absolute_path = self.host.filesystem.join(self.finder.layout_tests_dir(), test_path)
         test_parser = TestParser(absolute_path, self.host)
         if not test_parser.test_doc:
             return False
         return test_parser.is_jstest()