Python script to trim trailing white space recursively for all files matching a specified file mask regex.

trimwhitespace.py

#
# Usage:
#
# python trimwhitespace.py . .*\.js$
#
import argparse
import os
import re

parser = argparse.ArgumentParser(description='Trims trailing whitespace.')
parser.add_argument('root_directory', type=str, default='.', nargs='?',
                   help='directory to run the script in')
parser.add_argument('file_mask_regex', default=".*", nargs='?',
                   help='file name mask regex')

args = parser.parse_args()
file_mask_regex = re.compile(args.file_mask_regex)

print('Starting whitespace trimming. \
directory {0}, file mask {1}'.format(args.root_directory, args.file_mask_regex))

found_files = []
for path, subdirs, files in os.walk(args.root_directory):
    for name in files:
        found_files.append(os.path.join(path, name));

matched_files = [name for name in found_files if file_mask_regex.match(name)]

for file_path in matched_files:
    file_contents = ''
    with open(file_path) as f:
        file_contents = "\n".join((l.rstrip() for l in f.readlines())) + "\n"

    print('Trimming whitespace in {0}'.format(file_path))
    with open(file_path, "w") as f:
        f.write(file_contents)

print('Done')

Based upon tabs2spaces.py.