rustdoc: Enable smart punctuation

[camelid]

Split off from #76687.

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@rustbot modify labels: T-rustdoc C-enhancement

[camelid]

@rustbot claim

[camelid]

Uh, it looks like rustbot is editing my message and adding weird comments:

Split off from #76687.

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@rustbot modify labels: T-rustdoc C-enhancement

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[camelid]

Cc @Mark-Simulacrum

[camelid]

It looks like smart punctuation doesn't work in headers:

@marcusklaas wasn't able to reproduce this in pulldown itself; I'm guessing rustdoc is doing something special with headers. Cc @GuillaumeGomez

[Mark-Simulacrum]

Triagebot does that as a way of easily storing data per-issue (we could do it in the database now, we didn't have one back then). But it's expected and shouldn't really be a problem.

[pickfire]

Is this a good thing? Wouldn't keeping things as it is is better?

[Mark-Simulacrum]

@pickfire I think if you want to argue against doing this, giving reasons would be helpful.

I personally think given that we already use emoji and otherwise non-ASCII characters readily, it should be reasonable for us to generate smart quotes as well.

[pickfire]

I do think emoji and other non-ASCII characters if specified would be good except for smart quote. It's like saying to use greek question mark which is the same as semi-colon when a semi-colon was seen in documentation to make it look a bit cooler.

One thing is copying, when others are copying the text, it will copy the utf-8 version of smart quotes which when displayed in terminals which in turn will make it look ugly and hard for text processing.

Auto changing text to emoji I am okay with that. But not automatically changing single quotes, double quotes and semi-colons. Personally I don't see much benefit to that, usually if users want it they would specifically type it out but otherwise it would be similar. In my humble opinion, looks wise the smart quotes are more ugly, but easier to distinguish opening and closing quotes, but still when copied and pasted it may not look so good.