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From: Peter Otten <__peter__@web.de>
Subject: Re: bytearray inconsistencies?
Date: Sat, 21 Dec 2013 14:20:46 +0100
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Mark Lawrence wrote:

> On 21/12/2013 01:58, Ned Batchelder wrote:
>>
>> If you have a zero, you can split on it with:
>> bytestring.split(bytes([0])), but that doesn't explain why find can take
>> a simple zero, and split has to take a bytestring with a zero in it.
>>
> 
> Create a bytearray(range(256)) and partition it on 128.  I'd expect to
> see the original effectively cut in half with 128 as the separator.  You
> actually get the original with two empty bytearrays, which makes no
> sense to me at all.

>>> bytearray(b"alpha\x00\x00\x00beta").partition(0)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: empty separator
>>> bytearray(b"alpha\x00\x00\x00beta").partition(1)
(bytearray(b'alpha'), bytearray(b'\x00'), bytearray(b'\x00\x00beta'))
>>> bytearray(b"alpha\x00\x00\x00beta").partition(2)
(bytearray(b'alpha'), bytearray(b'\x00\x00'), bytearray(b'\x00beta'))

suggests that there is an implicit cast to bytearray

>>> bytearray(0)
bytearray(b'')
>>> bytearray(2)
bytearray(b'\x00\x00')

While consistent I don't see how this can ever be the desired behaviour and 
recommend that you file a bug report.
 
> I also looked in test_bytes.py, read as far as "XXX This is a mess" and
> promptly gave up.