[issue27623] int.to_bytes() and int.from_bytes(): raise ValueError when bytes count is zero

[Martin Panter]

Martin Panter added the comment:

I agree that the signed conversion cases should be an error.

However the unsigned case would break working code that I have written for bijective numeration. See _bytes_to_int() and _int_to_bytes() in Issue 20132, inc-codecs.diff, for example. Since non-zero unsigned conversions work by converting

N bytes  <->  0 <= value < 2^N

For N = 0, there is only one possible value, 0.

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nosy: +martin.panter

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