Reland of PyLint fixes for tools-webrtc and webrtc/tools

webrtc/tools/barcode_tools/helper_functions.py

 #!/usr/bin/env python
 # Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
 #
 # Use of this source code is governed by a BSD-style license
 # that can be found in the LICENSE file in the root of the source
 # tree. An additional intellectual property rights grant can be found
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
 import multiprocessing
 import os
 import subprocess
 import sys
 
 _DEFAULT_PADDING = 4
 
 
 class HelperError(Exception):
   """Exception raised for errors in the helper."""
   pass
 
 
-def zero_pad(number, padding=_DEFAULT_PADDING):
+def ZeroPad(number, padding=_DEFAULT_PADDING):
   """Converts an int into a zero padded string.
 
   Args:
     number(int): The number to convert.
     padding(int): The number of chars in the output. Note that if you pass for
       example number=23456 and padding=4, the output will still be '23456',
       i.e. it will not be cropped. If you pass number=2 and padding=4, the
       return value will be '0002'.
   Return:
     (string): The zero padded number converted to string.
   """
   return str(number).zfill(padding)
 
 
-def run_shell_command(cmd_list, fail_msg=None):
+def RunShellCommand(cmd_list, fail_msg=None):
   """Executes a command.
 
   Args:
     cmd_list(list): Command list to execute.
     fail_msg(string): Message describing the error in case the command fails.
 
   Return:
     (string): The standard output from running the command.
 
   Raise:
     HelperError: If command fails.
   """
   process = subprocess.Popen(cmd_list, stdout=subprocess.PIPE,
                              stderr=subprocess.PIPE)
   output, error = process.communicate()
   if process.returncode != 0:
     if fail_msg:
       print >> sys.stderr, fail_msg
     raise HelperError('Failed to run %s: command returned %d and printed '
                       '%s and %s' % (' '.join(cmd_list), process.returncode,
                                      output, error))
   return output.strip()
 
 
-def perform_action_on_all_files(directory, file_pattern, file_extension,
-                                start_number, action, **kwargs):
+def PerformActionOnAllFiles(directory, file_pattern, file_extension,
+                            start_number, action, **kwargs):
   """Function that performs a given action on all files matching a pattern.
 
   It is assumed that the files are named file_patternxxxx.file_extension, where
   xxxx are digits starting from start_number.
 
   Args:
     directory(string): The directory where the files live.
     file_pattern(string): The name pattern of the files.
     file_extension(string): The files' extension.
     start_number(int): From where to start to count frames.
     action(function): The action to be performed over the files. Must return
         False if the action failed, True otherwise. It should take a file name
         as the first argument and **kwargs as arguments. The function must be
         possible to pickle, so it cannot be a bound function (for instance).
 
   Return:
     (bool): Whether performing the action over all files was successful or not.
   """
   file_prefix = os.path.join(directory, file_pattern)
   file_number = start_number
 
   process_pool = multiprocessing.Pool(processes=multiprocessing.cpu_count())
   results = []
   while True:
-    zero_padded_file_number = zero_pad(file_number)
+    zero_padded_file_number = ZeroPad(file_number)
     file_name = file_prefix + zero_padded_file_number + '.' + file_extension
     if not os.path.isfile(file_name):
       break
     future = process_pool.apply_async(action, args=(file_name,), kwds=kwargs)
     results.append(future)
     file_number += 1
 
   successful = True
   for result in results:
     if not result.get():
       print "At least one action %s failed for files %sxxxx.%s." % (
           action, file_pattern, file_extension)
       successful = False
 
   process_pool.close()
   return successful