[cronet] replace filter with comprehension in build script

components/cronet/tools/generate_accept_languages.py

 # Copyright 2017 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.
 
 # This script generates a header containing a dictionary from locales to
 # accept language strings from chromium's .xtb files.  It is not very
 # robust at the moment, and makes some assumptions about the format of
 # the files, including at least the following:
 #   * assumes necessary data is contained only with files of the form
 #     components/strings/components_locale_settings_${LANG}.xtb
 #   * assumes ${LANG} is identified in the lang attribute of the root
 #     element of the file's xml data
 #   * assumes that there is only one relevant element with the
 #     IDS_ACCEPT_LANGUAGES attribute
 
 import os, re, sys
 from xml.etree import ElementTree
 
 STRINGS_DIR = sys.argv[2] + 'components/strings/'
 
 def extract_accept_langs(filename):
   tree = ElementTree.parse(STRINGS_DIR + filename).getroot()
   for child in tree:
     if child.get('id') == 'IDS_ACCEPT_LANGUAGES':
       return tree.get('lang'), child.text
 
 def gen_accept_langs_table():
-  return dict(filter(None, (extract_accept_langs(filename)
+  return dict(accept_langs for accept_langs in (extract_accept_langs(filename)
     for filename in os.listdir(STRINGS_DIR)
-    if re.match(r'components_locale_settings_\S+.xtb', filename))))
+    if re.match(r'components_locale_settings_\S+.xtb', filename))
+    if accept_langs)

[xunjieli, 2017/06/27 17:51:45]

This is getting rather long. Can you separate it out and make it more readable?

 
 HEADER = "NSDictionary* acceptLangs = @{"
 def LINE(locale, accept_langs):
   return '  @"' + locale + '" : @"' + accept_langs + '",'
 FOOTER = "};"
 
 def main():
   with open(sys.argv[1] + "/accept_languages_table.h", "w+") as f:
     print >>f, HEADER
     for (locale, accept_langs) in gen_accept_langs_table().items():
       print >>f, LINE(locale, accept_langs)
     print >>f, FOOTER
 
 if __name__ == "__main__":
   main()