Decoded command-line inputs to Unicode strings. Resolves #24.

src/caterpillar.py

 #!/usr/bin/env python2
 # -*- coding: utf-8 -*-
 
 # Copyright 2015 Google Inc. All Rights Reserved.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at
 #
 #     http://www.apache.org/licenses/LICENSE-2.0
@@ skipping 688 matching lines @@
     elif record.levelno == logging.WARNING:
       style = colorama.Fore.YELLOW + colorama.Style.BRIGHT
     elif record.levelno == logging.INFO:
       style = colorama.Fore.BLUE
     elif record.levelno == logging.DEBUG:
       style = colorama.Fore.CYAN + colorama.Style.DIM
 
     return style + super(Formatter, self).format(record)
 
 
+def unicode_arg(arg):
+  """Converts a bytestring command-line argument into a Unicode string."""
+  if sys.stdin.encoding:
+    return arg.decode(sys.stdin.encoding)
+
+  return arg.decode(sys.getfilesystemencoding())
+
+
 def main():
   """Executes the script and handles command line arguments."""
   # Set up parsers, then parse the command line arguments.
   desc = 'Semi-automatically convert Chrome Apps into progressive web apps.'
   parser = argparse.ArgumentParser(description=desc)
   parser.add_argument('-v', '--verbose', help='Verbose logging',
                       action='store_true')
   subparsers = parser.add_subparsers(dest='mode')
 
   parser_convert = subparsers.add_parser(
       'convert', help='Convert a Chrome App into a progressive web app.')
-  parser_convert.add_argument('input', help='Chrome App input directory')
   parser_convert.add_argument(
-      'output', help='Progressive web app output directory')
+      'input', help='Chrome App input directory', type=unicode_arg)
+  parser_convert.add_argument(
+      'output', help='Progressive web app output directory', type=unicode_arg)
   parser_convert.add_argument('-c', '--config', help='Configuration file',
-                              required=True, metavar='config')
+                              required=True, metavar='config', type=unicode_arg)
   parser_convert.add_argument('-f', '--force', help='Force output overwrite',
                               action='store_true')
 
   parser_config = subparsers.add_parser(
     'config', help='Print a default configuration file to stdout.')
-  parser_config.add_argument('output', help='Output config file path')
+  parser_config.add_argument('output', help='Output config file path',
+      type=unicode_arg)
   parser_config.add_argument('-i', '--interactive',
       help='Whether to interactively generate the config file',
       action='store_true')
 
   args = parser.parse_args()
 
   # Set up logging.
   logging_level = logging.DEBUG if args.verbose else logging.INFO
   logging.root.setLevel(logging_level)
   colorama.init(autoreset=True)
   logging_format = ':%(levelname)s:  \t%(message)s'
   formatter = Formatter(logging_format)
   handler = logging.StreamHandler(sys.stdout)
   handler.setFormatter(formatter)
   logging.root.addHandler(handler)
 
   # Main program.
   if args.mode == 'config':
     configuration.generate_and_save(args.output, args.interactive)
 
   elif args.mode == 'convert':
     config = configuration.load(args.config)
     convert_app(args.input, args.output, config, args.force)
 
 
 if __name__ == '__main__':
   sys.exit(main())