Update selected RFC 2822 references to RFC 5322
RFC 2822 was obsoleted by RFC 5322 in 2008. This updates references
to use the current standard in documentation, docstrings, and comments.
It preserves RFC 2822 references in legacy API components to maintain their
historical context.
RFC 822 → RFC 2822 → RFC 5322 progression is explained where relevant.
In some places specific sections of RFC are referenced where it seems helpful.
Scout rule was applied in some places and RFC mentions format was
normalized in doc strings and comments.
Similar to the rewrite of email/mime/image.py and associated test after the
deprecation of imghdr.py, thisrewrites email/mime/audio.py and associated
tests after the deprecation of sndhdr.py.
Closes#91885
* Rewrite imghdr inlining for clarity and completeness
* Move MIMEImage class back closer to the top of the file since it's the
important thing.
* Use a decorate to mark a given rule function and simplify the rule function
names for clarity.
* Copy over all the imghdr test data files into the email package's test data
directory. This way when imghdr is actually removed, it won't affect the
MIMEImage guessing tests.
* Rewrite and extend the MIMEImage tests to test for all supported
auto-detected MIME image subtypes.
* Remove the now redundant PyBanner048.gif data file.
* See https://github.com/python/cpython/pull/91461#discussion_r850313336
Co-authored-by: Oleg Iarygin <dralife@yandex.ru>
Co-authored-by: Oleg Iarygin <dralife@yandex.ru>
This is more RFC compliant (see issue) and fixes a problem with
signature verifiers rejecting the part when signed. There is some
amount of backward compatibility concern here since it changes
the output, but the RFC issue coupled with fixing the problem
with signature verifiers seems worth the small risk of breaking
code that depends on the current incorrect output.
