def decode(txt):
"""Decodes txt into a big-endian bytearray."""
if not isinstance(txt, str):
raise TypeError('a string is required')
if not txt:
raise Base58Error('string cannot be empty')
value = 0
for c in txt:
value = value * 58 + Base58.char_value(c)
result = int_to_bytes(value)
# Prepend leading zero bytes if necessary
count = 0
for c in txt:
if c != '1':
break
count += 1
if count:
result = bytes(count) + result
return result
def test_int_to_bytes():
assert util.int_to_bytes(456789) == b'\x06\xf8U'
def _exponent_to_bytes(exponent):
'''Convert an exponent to 32 big-endian bytes'''
return (bytes(32) + int_to_bytes(exponent))[-32:]
