When attempting to base64-decode a payload of invalid length (1 mod 4),
properly recognize and handle it. The given data will be returned as-is,
i.e. not decoded, along with a new defect, InvalidBase64LengthDefect.
(cherry picked from commit c3f55be7dd)
Co-authored-by: Tal Einat <taleinat+github@gmail.com>
This commit also restores the news item for 167256 that it looks like
Terry inadvertently deleted. (Either that, or I don't understand
now merging works...which is equally possible.)
Which also means that it is now producing *something* for any base64
payload, which is what leads to the couple of older test changes in
test_email. This is a slightly backward incompatible behavior change,
but the new behavior is so much more useful than the old (you can now
*reliably* detect errors, and any program that was detecting errors by
sniffing for a base64 return from get_payload(decode=True) and then doing
its own error-recovery decode will just get the error-recovery decode
right away). So this seems to me to be worth the small risk inherent
in this behavior change.
This patch also refactors the defect tests into a separate test file,
since they are no longer just parser tests.