[Biopython-dev] Pickle problem on 64 bit Windows with Python 3.4

[Peter Cock]

On Mon, Apr 21, 2014 at 6:00 PM, Manlio Calvi <manlio.calvi at gmail.com> wrote:
> I think we hit a stumbling block here, and maybe a serious one (but
> we'll be sure with more tests),  because this following error suggest
> me the way we used the pickling in the code changed or something
> strange happened in my config.
> Apart from installing a 3.3, I'll try to go experimental with 3.4, I
> want to understand if it is a problem with my build of 3.4 or if it is
> a general issue of 3.4 with some piece of BioPython.
>
> C:\Users\Public\BioPython3\biopython\Tests\SubsMat>python -c "import pickle; h =
>  open('acc_rep_mat.pik', 'rb'); m = pickle.load(h);h.close();print(m);
>
> Traceback (most recent call last):
>   File "<string>", line 1, in <module>
> _pickle.UnpicklingError: the STRING opcode argument must be quoted
>

Good - I was hoping that would happen - we have a clear test
case separate from the Biopython code now.

The pickle file acc_rep_mat.pik was created long ago (15 Nov 2000)
with Python 2, and I would have hoped it would be forward compatible.
This could be a regression in Python 3.4 itself (under Windows 64 bit
only)?

If anyone else has a 64 bit Windows machine and Python 3.4,
please try this and let us know what happens.

Thanks,

Peter