gh-91400: make sure email parsing dont unquote realnames with spaces

[carlbordum]

"Quote the name" portion of an email address in email.utils.formataddr() when it contains any spaces.

• Issue: email.utils.formataddr does not respect double spaces #91400

[gpshead]

any objections from folks on email-team?

there is a caveat to this bug fix: anyone who had been working around it by doing their own test for characters and adding ""s when it wouldn't already be quoted by our existing code will now wind up with extra properly escaped " characters within their result.

that doesn't seem like a bad problem though, it is a valid address. Attempting to detect and handle that as a special case would be messy logic and lead to potentially worse outcomes of intended ""s that should be escaped not being preserved.

[arhadthedev]

ping @python/email-team

[hugovk]

any objections from folks on email-team?

~Two years later and no objections, let's merge this.

[bitdancer]

Thanks for working on this, but see my analysis on the issue. The problem isn't with formataddr, which does the right thing, it's with parseaddr.

[bitdancer]

formataddr does the right thing. It's parseaddr that would need a fix, as well as _headervalueparser.

[bedevere-app]

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