#!/usr/bin/python2.7

##
# Calculate the size in bytes of a hg changeset diff
#
# Example:
#   hg diff -r tip | buildscripts/hg_diff_size.py
##

import fileinput

def is_diff_line(line):
	return (line.startswith('-') and not line.startswith('--- ')) or \
		(line.startswith('+') and not line.startswith('+++ '))

filename = None
f = fileinput.input()
try:
	for line in f:
		if f.isfirstline():
			if filename:
				print filename,": size changed by", size_diff, "bytes."

			size_diff = 0
			filename = f.filename()

		if is_diff_line(line):
			size_diff += len(line[1:])

	if filename:
		print filename,": size changed by", size_diff, "bytes."

finally:
	f.close()