[Beta] Change html_root_url to point to the latest beta documentation

[FaultyRAM]

Partially addresses #30693 by changing html_root_url on all relevant crates to point to the latest beta docs instead of nightly. Fully addressing the issue would also involve updating html_root_url on stable to point to the current stable docs.

[rust-highfive]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @nikomatsakis (or someone else) soon.

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[rust-highfive]

Warning

• Pull requests are usually filed against the master branch for this repo, but this one is against beta. Please double check that you specified the right target!

[alexcrichton]

Thanks for the PR! Currently we don't have an automated process for doing this, but we probably should. The failure mode here is that when you compile documentation against the standard library (the stable version) it'll link to nightly instead of that stable version. This isn't so bad, and I'd be wary of basically having to make a PR every time we make a release, could we automate this in some fashion to happen without us making PRs?

cc @brson

[brson]

This does call for automation of some sort. We've discussed it before and not come to any conclusions. ISTM the only reasonable thing to do is replace this text during the build process, but there doesn't seem to be any existing machanism that will work for it.

There are other reasons to have a general facility for text replacement - the version numbers for all the crates seem to be set to "0.0.0", which is completely wrong. They should all be the same as the compiler version.

Accepting this PR won't accomplish much since it will be bogus on the stable build.

[nikomatsakis]

r? @brson (I have no idea here)

[brson]

I prefer to pursue something like #19603, so closing this, but @FaultyRAM if you wanted to purse #19603 we can probably come up with a solution.