It doesn't look quite right, because the lines are too far apart,
and it's not going to be announced by screenreaders as a menu button,
since that's not what the symbol means.
This adds a real tooltip and uses a better drawing of the icon.
This is a redesign of the feature, with parts pulled from
https://github.com/rust-lang/rust/pull/119049
but with a button that looks more like a button and matches the
one used on other sidebar pages.
rustdoc: allow resizing the sidebar / hiding the top bar
Fixes#97306
Preview: http://notriddle.com/rustdoc-html-demo-4/sidebar-resize/std/index.html
## Summary
This feature adds:
1. A checkbox to the Settings popover to hide the persistent navigation bar (the sidebar on large viewports and the top bar on small ones).
2. On large viewports, it adds a resize handle to the persistent sidebar. Resizing it into nothing is equivalent to turning off the persistent navigation bar checkbox in Settings.
3. If the navigation bar is hidden, a toolbar button to the left of the search appears. Clicking it brings the navigation bar back.
## Motivation
While "mobile mode" is definitely a good default, it's not the only reason people have wanted to hide the sidebar:
* Some people use tiling window managers, and don't like rustdoc's current breakpoints. Changing the breakpoints might help with that, but there's no perfect solution, because there's a gap between "huge screen" and "smartphone" where reasonable people can disagree about whether it makes sense for the sidebar to be on-screen. https://github.com/rust-lang/rust/issues/97306
* Some people ask for ways to reduce on-screen clutter because it makes it easier to focus. There's not a media query for that (and if there was, privacy-conscious users would turn it off). https://github.com/rust-lang/rust/issues/59829
This feature is designed to avoid these problems. Resizing the sidebar especially helps, because it provides a way to hide the sidebar without adding a new top-level button (which would add clutter), and it provides a way to make rustdoc play nicer in complex, custom screen layouts.
## Guide and Reference-level explanation
On a desktop or laptop with a mouse, resize the sidebar by dragging its right edge.
On any browser, including mobile phones, the sticky top bar or side bar can be hidden from the Settings area (the button with the cog wheel, next to the search bar). When it's hidden, a convenient button will appear on the search bar's left.
## Drawbacks
This adds more JavaScript code to the render blocking area.
## Rationale and alternatives
The most obvious way to allow people to hide the sidebar would have been to let them "manually enter mobile mode." The upside is that it's a feature we already have. The downside is that it's actually really hard to come up with a terse description. Is it:
* A Setting that forces desktop viewers to always have the mobile-style top bar? If so, how do we label it? Should it be visible on mobile, and, if so, does it just not do anything?
* A persistent hide/show sidebar button, present on desktop, just like on mobile? That's clutter that I'd like to avoid.
## Prior art
* The new file browser in GitHub uses a similar divider with a mouse-over indicator
* mdBook and macOS Finder both allow you to resize the sidebar to nothing as a gesture to hide it
* https://www.nngroup.com/articles/drag-drop/
## Future possibilities
https://rust-lang.zulipchat.com/#narrow/stream/266220-rustdoc/topic/Table.20of.20contents proposes a new, second sidebar (a table of contents). How should it fit in with this feature? Should it be resizeable? Hideable? Can it be accessed on mobile?
This is about equally readable, a lot more terse, and stops
special-casing functions and methods.
```console
$ du -hs doc-old/ doc-new/
671M doc-old/
670M doc-new/
```
This makes two changes, based on experimenting with different browsers:
- It debounces resizing the body text. This improves behavior on huge
pages like struct.Vec.html, because it doesn't have to do layout.
- It does the sidebar width updates directly on the sidebar instead of
doing it on the `<HTML>` element. Doing it on `<HTML>` causes it
to recalculate CSS for the entire document, also causing layout jank.
This commit makes three changes for consistency and readability:
- It shows the sibling navigation on module pages. It's weird
that it didn't work before, and is inconsistent with everything
else (even Crates have sibling navigation with other Crates).
- It hides the "In [parent]" header if it's the same as the
current crate, and if there's no other header between them.
We need to keep it on modules and types, since they have
their own header and data between them, and we don't want
to show siblings under a header implying that they're children.
- It adds a margin to deal with the headers butting directly into
the branding lockup.
This should result in a layout for the actual standard library,
when built on CI, that looks like this:
_____
/ \ std
| R | 1.74.0-nightly
\_____/
(203c57dbe 2023-09-17)
Having the whole version as one string caused it to flex wrap,
because the sidebar isn't wide enough to fit the whole thing.
This commit changes the layout to something a bit less "look at my logo!!!111"
gigantic, and makes it clearer where clicking the logo will actually take you.
It also means the crate name is persistently at the top of the sidebar, even
when in a sub-item page, and clicking that name takes you back to the root.
| | Short crate name | Long crate name |
|---------|------------------|-----------------|
| Root | ![short-root] | ![long-root]
| Subpage | ![short-subpage] | ![long-subpage]
[short-root]: https://github.com/rust-lang/rust/assets/1593513/fe2ce102-d4b8-44e6-9f7b-68636a907f56
[short-subpage]: https://github.com/rust-lang/rust/assets/1593513/29501663-56c0-4151-b7de-d2637e167125
[long-root]: https://github.com/rust-lang/rust/assets/1593513/f6a385c0-b4c5-4a9c-954b-21b38de4192f
[long-subpage]: https://github.com/rust-lang/rust/assets/1593513/97ec47b4-61bf-4ebe-b461-0d2187b8c6cahttps://notriddle.com/rustdoc-html-demo-4/logo-lockup/image/index.htmlhttps://notriddle.com/rustdoc-html-demo-4/logo-lockup/crossbeam_channel/index.htmlhttps://notriddle.com/rustdoc-html-demo-4/logo-lockup/adler/struct.Adler32.htmlhttps://notriddle.com/rustdoc-html-demo-4/logo-lockup/crossbeam_channel/struct.Sender.html
This improves visual information density (the construct with the logo and
crate name is *shorter* than the logo on its own, because it's not
square) and navigation clarity (we can now see what clicking the Rust logo
does, specifically).
Compare this with the layout at [Phoenix's Hexdocs] (which is what this
proposal is closely based on), the old proposal on [Internals Discourse]
(which always says "Rust standard library" in the sidebar, but doesn't do the
side-by-side layout).
[Phoenix's Hexdocs]: https://hexdocs.pm/phoenix/1.7.7/overview.html
[Internals Discourse]: https://internals.rust-lang.org/t/poc-of-a-new-design-for-the-generated-rustdoc/11018
In newer versions of rustdoc, the crate name and version are always shown in
the sidebar, even in subpages. Clicking the crate name does the same thing
clicking the logo always did: return you to the crate root.
While this actually takes up less screen real estate than the old layout on
desktop, it takes up more HTML. It's also a bit more visually complex.
I could do what the Internals POC did and keep the vertically stacked layout
all the time, instead of doing a horizontal stack where possible. It would
take up more screen real estate, though.
This design is lifted almost verbatim from Hexdocs. It seems to work for them.
[`opentelemetry_process_propagator`], for example, has a long application name.
[`opentelemetry_process_propagator`]: https://hexdocs.pm/opentelemetry_process_propagator/OpentelemetryProcessPropagator.html
Has anyone written the rationale on why the Rust logo shows up on projects that
aren't the standard library? If we turned it off on non-standard crates by
default, it would line wrap crate names a lot less often.
Or maybe we should encourage crate authors to include their own logo more
often? It certainly helps give people a better sense of "place."
I'm not sure of anything that directly follows up this one. Plenty of other
changes could be made to improve the layout, like
* coming up with a less cluttered way to do disclosure (there's a lot of `[-]`
on the page)
* doing a better job of separating lateral navigation (vec::Vec links to
vec::IntoIter) and the table of contents (vec::Vec links to vec::Vec::new)
* giving readers more control of how much rustdoc hows them, and giving doc
authors more control of how much it generates
* better search that reduces the need to browse
But those are mostly orthogonal, not future possibilities unlocked by this change.
This makes "existential type" look slightly cramped (though still
readable), but it makes all other typenames look better. Existential
types are currently very rare, and we can always tweak this later if
necessary.
The recent PR #110688 added info about an item's kind before its name in
search results. However, because the kind and name are inline with no
alignment, it's now hard to visually scan downward through the search
results, looking at item names. This PR fixes that by horizontally
aligning search results such that there are now two columns of
information.
