Lars Ingebrigtsen <larsi@gnus.org> writes:

> Alex Bochannek <alex@bochannek.com> writes:
>
>> I don't suspect this problem is widespread in other uses of the base64
>> decoder, so it seems appropriate to me to just patch
>> gnus-convert-face-to-png to generate the right amount of padding.
>
> Hm...  I think it would be nice to have a utility function to fix up
> base64 padding, and then gnus-convert-face-to-png could just use that?
>
> It should work for both base64 that has newlines inserted and not.

Took me a little while, but I broke this out into a utility function as
you suggested. I also wrote some tests for it. As part of me getting
familiar with ERT, I added a bunch of tests for gnus-string< and
gnus-string>, which I hope are useful. They should probably be in a
separate commit, but I leave that up to you.