Continue String to Symbol conversion in rustdoc
Follow-up of https://github.com/rust-lang/rust/pull/80091.
This PR is already big enough so I'll stop here before the next one.
r? `@jyn514`
Use more symbols in rustdoc
Builds on https://github.com/rust-lang/rust/pull/80044 and should not be merged before.
I want to test if this is actually faster before merging it, there was a lot of `to_string()` calls so I'm not sure it will actually help. That means I have to wait for 80044 to get merged before running perf.
r? `@ghost`
[rustdoc] Calculate span information on demand instead of storing it ahead of time
This brings `size_of<clean::types::Span>()` down from over 100 bytes (!!) to only 12, the same as rustc. It brings `Item` down even more, from `784` to `680`.
~~TODO: I need to figure out how to do this for the JSON backend too. That uses `From` impls everywhere, which don't allow passing in the `Session` as an argument. `@P1n3appl3,` `@tmandry,` maybe one of you have ideas?~~ Figured it out, fortunately only two functions needed to be changed. I like the `convert_x()` format better than `From` everywhere but I'm open to feedback.
Helps with #79103
Previously Markdown documentation was not rendered to HTML for search results,
which led to the output not being very readable, particularly for inline code.
This PR fixes that by rendering Markdown to HTML with the help of pulldown-cmark
(the library rustdoc uses to parse Markdown for the main text of documentation).
However, the text for the title attribute (the text shown when you hover over an
element) still uses the plain-text rendering since it is displayed in browsers
as plain-text.
Only these styles will be rendered; everything else is stripped away:
* *italics*
* **bold**
* `inline code`
Remove duplicate `Trait::auto` field
It was exactly the same as `is_auto`.
I found this while working on #78082, but it's not required for that PR.
r? `@GuillaumeGomez`
The main change is that `UnstableOptions::from_environment` now requires
an (optional) crate name. If the crate name is unknown (`None`), then the new feature is not available and you still have to use `RUSTC_BOOTSTRAP=1`. In practice this means the feature is only available for `--crate-name`, not for `#![crate_name]`; I'm interested in supporting the second but I'm not sure how.
Other major changes:
- Added `Session::is_nightly_build()`, which uses the `crate_name` of
the session
- Added `nightly_options::match_is_nightly_build`, a convenience method
for looking up `--crate-name` from CLI arguments.
`Session::is_nightly_build()`should be preferred where possible, since
it will take into account `#![crate_name]` (I think).
- Added `unstable_features` to `rustdoc::RenderOptions`
There is a user-facing change here: things like `RUSTC_BOOTSTRAP=0` no
longer active nightly features. In practice this shouldn't be a big
deal, since `RUSTC_BOOTSTRAP` is the opposite of stable and everyone
uses `RUSTC_BOOTSTRAP=1` anyway.
- Add tests
Check against `Cheat`, not whether nightly features are allowed.
Nightly features are always allowed on the nightly channel.
- Only call `is_nightly_build()` once within a function
- Use booleans consistently for rustc_incremental
Sessions can't be passed through threads, so `read_file` couldn't take a
session. To be consistent, also take a boolean in `write_file_header`.
This is mostly motivated by docs.rs. It's really weird
when arrow keys work in the top dropdown menu, but don't work
in other dropdown menus on the same page.
rustdoc has various user-configurable preferences. These are recorded
in web Local Storage (where available). But we want to provide a way
to configure the default default, including for when web storage is
not available.
getSettingValue is the function responsible for looking up these
settings. Here we make it fall back some in-DOM data, which
ultimately comes from RenderOptions.default_settings.
Using HTML data atrtributes is fairly convenient here, dsspite the
need to transform between snake and kebab case to avoid the DOM
converting kebab case to camel case (!)
We cache the element and dataset lookup in a global variable, to
ensure that getSettingValue remains fast.
The DOM representation has to be in an element which precedes the
inclusion of storage.js. That means it has to be in the <head> and we
should not use an empty <div> as the container (although most browsers
will accept that). An empty <script> element provides a convenient
and harmless container object. <meta> would be another possibility
but runs a greater risk of having unwanted behaviours on weird
browsers.
We trust the RenderOptions not to contain unhelpful setting names,
which don't fit nicely into an HTML attribute. It's awkward to quote
dataset keys.
Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
Avoid extraneous space between visibility kw and ident for statics
Today, given a static like `static mut FOO: usize = 1`, rustdoc would
emit `static mut FOO: usize = 1`, as it emits both the mutability kw
with a space and reserves a space after the mutability kw. This patch
fixes that misformatting.
This patch also adds some tests for emit of other statics, as I could
not find an existing test devoted to statics.
Add settings to rustdoc to use the system theme
This PR adds new settings to `rustdoc` to use the operating system color scheme.

`rustdoc` actually had [basic support for this](b1af43bc63/src/librustdoc/html/static/storage.js (L121)), but the setting wasn't visible and couldn't be set back once the theme was explicitly set by the user. It also didn't update if the operating system theme preference changed while viewing a page.
I'm using [this method](https://developer.mozilla.org/en-US/docs/Web/CSS/Media_Queries/Testing_media_queries#Receiving_query_notifications) to query and listen to changes to the `(prefers-color-scheme: dark)` media query. I kept the old method (based on `getComputedStyle`) as a fallback in case the user-agent doesn't support `window.matchMedia` (so like... [pretty much nobody](https://caniuse.com/?search=matchMedia)).
Since there's now more than one official ""dark"" theme in `rustdoc` (and also to support custom/third-party themes), the preferred dark and light themes can be configured in the settings page (the defaults are just "dark" and "light").
This is also my very first "proper" PR to Rust! Please let me know if I did anything wrong :).
Today, given a static like `static mut FOO: usize = 1`, rustdoc would
emit `static mut FOO: usize = 1`, as it emits both the mutability kw
with a space and reserves a space after the mutability kw. This patch
fixes that misformatting.
This patch also adds some tests for emit of other statics, as I could
not find an existing test devoted to statics.
For sub-items on a page don't show cfg that has already been rendered on
a parent item. At its simplest this means not showing anything that is
shown in the portability message at the top of the page, but also for
things like fields of an enum variant if that variant itself is
cfg-gated then don't repeat those cfg on each field of the variant.
This does not touch trait implementation rendering, as that is more
complex and there are existing issues around how it deals with doc-cfg
that need to be fixed first.