bug#35739: Bad signature from GNU ELPA

[Stefan Monnier]

>> > I'd like us not to change that behavior by default.
>> I think in this case we need to define it (i.e. document what it means
>> to insert decoded text into a unibyte buffer).
> Why do we have to define that only for that specific function?

I didn't mean for this specific function, I meant in general.

> And why is that relevant to the issue at hand, which is not to make
> backward-incompatible changes in existing APIs?

I consider myself fairly well versed in Emacs's coding systems.  Yet,
I don't know what decoding text into a unibyte buffer will do and can't
find any doc that describes it.

I such a context, I think preserving such a behavior is harmful in the
long term because it will keep fundamentally buggy code half-working
and keep spreading confusion about how coding systems work and people
copy&pasting broken code.

In the long term, I think we're better off introducing limited
breakage where it leads to clearer errors that help clear up such
confusions and fix bugs.


        Stefan