email.charset: viscii charset registered but no Python codec exists

[stefanzetzsche]

Bug report

Bug description:

Issue

The email.charset module registers viscii in its CHARSETS dict with QP header and body encoding, but Python has no built-in codec named viscii. Any encoding operation on Charset('viscii') raises LookupError.

Reproducer

from email.charset import Charset
cs = Charset('viscii')
cs.header_encode('')  # LookupError: unknown encoding: viscii

CPython versions tested on:

CPython main branch

Operating systems tested on:

No response

Linked PRs

• gh-145834: email.charset: remove viscii from CHARSETS — no Python codec exists #145835

[picnixz]

I don't think it a bug. The Python codec can be added by an external library. So it's ok ti keep it for backward compatibility.

[stefanzetzsche]

Fair, thanks. Worth noting that viscii is the only charset in CHARSETS that doesn't work out of the box, every other entry has a built-in codec. Either way, closing the issue.