rustdoc: add stability and source links to the methods; w/ style tweaks

[adrientetar]

• Pull-in changes from rustdoc: Add stability and source links to the methods #13802, with a rebase
• Fix again link selectors (unrelated to the original PR)
• Show stability attributes with color pellets, add more explicit titles that will appear on hover
• Keep using [src] for the source links, don't show them on methods until (method+description) is hovered

Example: http://adrientetar.legtux.org/cached/rust-docs/foo.htm

cc @lifthrasiir. Closes #13802, which fixes #12932.

r? @alexcrichton

[alexcrichton]

It looks like some of the bullets don't have titles (such as fn frozen() and the outer struct), but it looks like you had logic to make it not an empty string. Is the preview example up to date?

[alexcrichton]

The implementation is fine by me. The bullets look like they're a little small, but once you see them everywhere they may be pretty obvious. The color scheme is also helpful I think.

[adrientetar]

@alexcrichton Right, updated.

[adrientetar]

Repushed latest commit without changes to see if Travis triggers. Seems like it doesn't.

[alexcrichton]

(needs a rebase)

[adrientetar]

The first commit was a pain to work with but, rebased.

[alexcrichton]

After thinking a little bit about this, what would you think about removing the bullets and making the left-hand side a colored bar going up an down the page? That way it may be a little clearer and all of the stability levels will line up.

It may also be nice to have the stability levels extend to the height of the entire method block (the whole function). Does that make sense?

[huonw]

FWIW, I think the mouse-over only text for the stability attributes is hard to find, and is essentially unusable on a touchscreen.

[yuriks]

I think the bullets are fine for the more stable levels, but experimental and deprecated items should have more noticeable markers, I could see myself just looking over them as "just more bullets". So the experimental and deprecated levels should get a rectangular tag instead. Given that, I think the bullets for stable and below could also be only visible when hovering. (alexchrichton's idea also sounds good.)

[adrientetar]

I will work on it this week-end.

@lifthrasiir: do you know why I see cx being undefined inside the impl block? Is it something gone wrong with the rebase?

[lifthrasiir]

@adrientetar I think some merged changes after the initial PR had inserted a reference to the context. If they are present in the impl Context block, you can safely change those to self to get it work (except for the nested functions). It seems that both problematic references are indeed in the impl Context block.

[alexcrichton]

Closing due to inactivity, but feel free to reopen with a rebase!

[adrientetar]

I will revive this when I've got some time.