update.py

#!/usr/bin/env python3

import os
import re
import sys
import fileinput
import argparse
from datetime import datetime

parser = argparse.ArgumentParser(
	usage='%(prog)s [OPTION]',
	description='Updates license file(s) to the current year.'
)

parser.add_argument('-f', '--files', help='Multiline string of file paths', required=True)
parser.add_argument('-e', '--exclude', help='Multiline string of words in author to exclude')
parser.add_argument('-r', '--no-range', help='Only keep last year instead of range of years')
args = parser.parse_args()

paths = []
for line in iter(args.files.replace('\\n', '\n').splitlines()):
	if line != '':
		if not os.path.isfile(line):
			print(f'file not found at path "{line}"')
			sys.exit(1)
		elif line in paths:
			print(f'duplicate path "{line}"')
			sys.exit(1)
		else:
			paths.append(line)

excludes = []
for line in iter((args.exclude or '').replace('\\n', '\n').splitlines()):
	if line != '':
		if line in excludes:
			print(f'duplicate exclude "{line}"')
			sys.exit(1)
		else:
			excludes.append(line.lower())

PATTERN = re.compile(r'^([Cc]opyright.+) ([0-9-]{4,9}) (.+)$')
NEW_YEAR = datetime.now().year

for line in fileinput.input(files=paths, inplace=True):
	match = PATTERN.match(line)
	if match and match.group(2) != str(NEW_YEAR) and not any(w in match.group(3).lower() for w in excludes):
		if args.no_range:
			sys.stdout.write(f'{match.group(1)} {NEW_YEAR} {match.group(3)}\n')
		else:
			sys.stdout.write(f'{match.group(1)} {match.group(2)[:4]}-{NEW_YEAR} {match.group(3)}\n')
	else:
		sys.stdout.write(line)