Lib/fontTools/misc/textTools.py

"""fontTools.misc.textTools.py -- miscellaneous routines."""


from __future__ import print_function, division, absolute_import
from fontTools.misc.py23 import *
import ast
import string


# alias kept for backward compatibility
safeEval = ast.literal_eval


def readHex(content):
	"""Convert a list of hex strings to binary data."""
	return deHexStr(strjoin(chunk for chunk in content if isinstance(chunk, basestring)))


def deHexStr(hexdata):
	"""Convert a hex string to binary data."""
	hexdata = strjoin(hexdata.split())
	if len(hexdata) % 2:
		hexdata = hexdata + "0"
	data = []
	for i in range(0, len(hexdata), 2):
		data.append(bytechr(int(hexdata[i:i+2], 16)))
	return bytesjoin(data)


def hexStr(data):
	"""Convert binary data to a hex string."""
	h = string.hexdigits
	r = ''
	for c in data:
		i = byteord(c)
		r = r + h[(i >> 4) & 0xF] + h[i & 0xF]
	return r


def num2binary(l, bits=32):
	items = []
	binary = ""
	for i in range(bits):
		if l & 0x1:
			binary = "1" + binary
		else:
			binary = "0" + binary
		l = l >> 1
		if not ((i+1) % 8):
			items.append(binary)
			binary = ""
	if binary:
		items.append(binary)
	items.reverse()
	assert l in (0, -1), "number doesn't fit in number of bits"
	return ' '.join(items)


def binary2num(bin):
	bin = strjoin(bin.split())
	l = 0
	for digit in bin:
		l = l << 1
		if digit != "0":
			l = l | 0x1
	return l


def caselessSort(alist):
	"""Return a sorted copy of a list. If there are only strings
	in the list, it will not consider case.
	"""

	try:
		return sorted(alist, key=lambda a: (a.lower(), a))
	except TypeError:
		return sorted(alist)


def pad(data, size):
	r""" Pad byte string 'data' with null bytes until its length is a
	multiple of 'size'.

	>>> len(pad(b'abcd', 4))
	4
	>>> len(pad(b'abcde', 2))
	6
	>>> len(pad(b'abcde', 4))
	8
	>>> pad(b'abcdef', 4) == b'abcdef\x00\x00'
	True
	"""
	data = tobytes(data)
	if size > 1:
		remainder = len(data) % size
		if remainder:
			data += b"\0" * (size - remainder)
	return data


if __name__ == "__main__":
	import doctest, sys
	sys.exit(doctest.testmod().failed)