rustdoc: unstable should show feature name and issue

[m4rw3r]

Implemented #27759

Example:

[rust-highfive]

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

If any changes to this PR are deemed necessary, please add them as extra commits. This ensures that the reviewer can see what has changed since they last reviewed the code. The way Github handles out-of-date commits, this should also make it reasonably obvious what issues have or haven't been addressed. Large or tricky changes may require several passes of review and changes.

Please see the contribution instructions for more information.

[killercup]

Very cool!

If the screenshot is accurate, I'd suggest making the font size of the name of the feature a bit smaller and changing it's background to transparent.

[m4rw3r]

I pretty much just imitated the style used by github in that example in the linked issue since it seemed like it made the feature name clear, but here is an alternative without the background and with a slightly smaller font-size:

Is this better?

[killercup]

@m4rw3r I like this second version better. I'm no authority on the visual design of rustdoc, though :)

[alexcrichton]

Awesome, thanks @m4rw3r! A few thoughts:

• Could this avoid adding a CLI option to rustdoc for now? The flag interface is already a bit too ambitious I think and it'd be nice to keep it under control!
• The new issue_tracker_base_url probably only needs to be added to the standard library and facade crates, it should be ok to omit for all the rustc_private and above crates
• Could you host these docs so we could poke around a bit?
• Could you add a test for this as well? (see src/test/rustdoc)

[m4rw3r]

@alexcrichton I put a copy of the docs rendered with my branch on github pages: http://m4rw3r.github.io/rust/std/result/enum.Result.html#method.expect

[alexcrichton]

Thanks @m4rw3r!

[steveklabnik]

looks really nice

[tshepang]

so kool

[alexcrichton]

@bors: r+ 6532a08

Thanks @m4rw3r! Also feel free to ping a PR whenever you force push it, unfortunately github doesn't send out notifications on those events :(

[m4rw3r]

@alexcrichton iirc I did not force-push this one, but I will keep that in mind if I do force push something. Github had some problems with git-pull about 2 days ago, that caused the travis build to be delayed.

Now on to find some other thing to implement for rustdoc :)

[bors]

⌛ Testing commit 6532a08 with merge e9b74a9...

[bors]

☀️ Test successful - auto-linux-32-nopt-t, auto-linux-32-opt, auto-linux-64-nopt-t, auto-linux-64-opt, auto-linux-64-x-android-t, auto-mac-32-opt, auto-mac-64-nopt-t, auto-mac-64-opt, auto-win-gnu-32-nopt-t, auto-win-gnu-32-opt, auto-win-gnu-64-nopt-t, auto-win-gnu-64-opt, auto-win-msvc-32-opt, auto-win-msvc-64-opt