bootstrap: Restore missing --bulk-dirs for rust-docs, rustc-docs
The `--bulk-dirs` argument was removed for rust-docs in commit c768ce1384 and rustc-docs in commit 8ca46fc7a8 (#79788), presumably by mistake; that slowed down installation of rust-docs from under a second to some twenty *minutes*. Restoring `--bulk-dirs` reverses this slowdown.
Fixes#80684.
Cc `@pietroalbini.`
Support `x.py doc std --open`
I usually run this command:
```
./x.py doc std --stage 1 --jobs 8
```
Then I gave a try to `--open` and realized it wasn't working. I finally realized it was simply because it was only handling paths starting with `library`. This PR allows to handle both kinds of paths.
cc ``@jyn514``
r? ``@Mark-Simulacrum``
Write Rustdoc titles like "x in crate::mod - Rust"
This makes Rustdoc titles for items be like "Widget in cratename::blah::foo - Rust". Titles for modules and other non-items are unchanged, and still read like "cratename::blah::foo - Rust". This makes managing several open Rustdoc tabs easier.

This also adds some tests for the new title behavior.
Closes#84371.
Upgrade `expat` dependency in riscv64 to newer version.
The old version was renamed to `expat-2.2.6-RENAMED-VULNERABLE-PLEASE-USE-2.3.0-INSTEAD`. :)
r? `@Mark-Simulacrum`
This makes Rustdoc titles for items read like
"x in cratename::blah::foo - Rust". Title for modules and other
non-items are unchanged, and still read like
"doccratenameconst::blah::foo - Rust". This makes managing several open
Rustdoc tabs easier.
Closes#84371.
Suggest `.as_ref()` on borrow error involving `Option`/`Result`
When encountering a E0382 borrow error involving an `Option` or `Result`
provide a suggestion to use `.as_ref()` on the prior move location to
avoid the move.
Fix#84165.
rustdoc: Simplify some document functions
* Remove `prefix` param of `document_short/full`, `render_markdown`, as its always an empty string.
* Remove `Option` wrapping of `document_short` `parent`, as its always `Some`.
rustdoc: Show nag box on IE11
Rustdoc doesn't work on IE11. It's been broken for months, it isn't supported by the [tiered browser support list], it's even more severely broken on other Rust websites, and IE11 doesn't support the `<details>` tag that we want to use.
In the interest of honesty, let's give an actual error message for anyone on IE11.
[tiered browser support list]: https://github.com/rust-lang/rfcs/blob/master/text/1985-tiered-browser-support.md
coverage of async function bodies should match non-async
This fixes some missing coverage within async function bodies.
Commit 1 demonstrates the problem in the fixed issue, and commit 2 corrects it.
Fixes: #83985
Add coverage to continue statements
`continue` statements were missing coverage. This was particularly
noticeable in a match pattern that contained only a `continue`
statement, leaving the branch appear uncounted. This PR addresses the
problem and adds tests to prove it.
r? `@tmandry`
cc: `@wesleywiser`
When encountering a E0382 borrow error involving an `Option` or `Result`
provide a suggestion to use `.as_ref()` on the prior move location to
avoid the move.
Fix#84165.
* Remove `prefix` param of `document_short/full`, `render_markdown`, as its always an empty string.
* Remove `Option` wrapping of `document_short` `parent`, as its always `Some`.
Rustdoc doesn't work on IE11. It's been broken for months, it isn't supported
by the [tiered browser support list], it's even more severely broken on other
Rust websites, and IE11 doesn't support the `<details>` tag that we want
to use.
In the interest of honesty, let's give an actual error message for anyone
on IE11.
[tiered browser support list]: https://github.com/rust-lang/rfcs/blob/master/text/1985-tiered-browser-support.md
Remove unused footer section
I realized yesterday while working on docs.rs that rustdoc was generating a "footer"section that it doesn't use. No need to keep it then.
r? `@jyn514`
rustdoc: Reduce visual weight of attributes.
Followup from #83337. As part of that PR, we stopped hiding attributes behind a toggle, because most things have just zero or one attributes. However, this made clear that the current rendering of attributes emphasizes them a lot, which distracts from function signatures. This PR changes their color of attributes to be the same as the toggles, and reduces their font weight.
This also removes `#[lang]` from the list of ALLOWED_ATTRIBUTES. This attribute is an implementation detail rather than part of the public-facing documentation.

Demo at https://hoffman-andrews.com/rust/de-emph-attr/std/string/struct.String.html#method.trim