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from ..exceptions import DeserializationError, SerializationError
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from ..utils import int_to_big_endian, big_endian_to_int, is_integer, ascii_chr
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class BigEndianInt(object):
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"""A sedes for big endian integers.
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:param l: the size of the serialized representation in bytes or `None` to
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use the shortest possible one
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def __init__(self, l=None):
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def serialize(self, obj):
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if not is_integer(obj):
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raise SerializationError('Can only serialize integers', obj)
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if self.l is not None and obj >= 256**self.l:
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raise SerializationError('Integer too large (does not fit in {} '
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'bytes)'.format(self.l), obj)
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raise SerializationError('Cannot serialize negative integers', obj)
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s = int_to_big_endian(obj)
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if self.l is not None:
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return b'\x00' * max(0, self.l - len(s)) + s
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def deserialize(self, serial):
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if self.l is not None and len(serial) != self.l:
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raise DeserializationError('Invalid serialization (wrong size)',
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if self.l is None and len(serial) > 0 and serial[0:1] == ascii_chr(0):
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raise DeserializationError('Invalid serialization (not minimal '
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serial = serial or b'\x00'
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return big_endian_to_int(serial)
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big_endian_int = BigEndianInt()
added
removed
rlp/sedes/big_endian_int.py
