1. Extract the tests for whether or not we have workable localStorage out into
a helper method, so it can be more easily reused
2. Use it in getCurrentValue() too, for the same reasons, as suggested in code
review
If the user's cookie/persistent storage setting forbid access to localStorage,
catch the exception and abort the access.
Currently, attempting to use the expand/contract links at the top of the page
for structs/consts/etc. fails due to an unhandled error while accessing
localStorage, if such access is forbidden, as the exception from the failed
access propagates all the way out, interrupting the expand/contract. Instead, I
would like to degrade gracefully; the access won't happen (the collapse/expand
state won't get persisted) but the actual expanding/contracting of the item
will go on to succeed.
Fixes#55079
rustdoc: give proc-macros their own pages
related to https://github.com/rust-lang/rust/issues/49553 but i don't think it'll fix it
Currently, rustdoc doesn't expose proc-macros all that well. In the source crate, only their definition function is exposed, but when re-exported, they're treated as a macro! This is an awkward situation in all accounts. This PR checks functions to see whether they have any of `#[proc_macro]`, `#[proc_macro_attribute]`, or `#[proc_macro_derive]`, and exposes them as macros instead. In addition, attributes and derives are exposed differently than other macros, getting their own item-type, CSS class, and module heading.
Function-like proc-macros are lumped in with `macro_rules!` macros, but they get a different declaration block (i'm open to tweaking this, it's just what i thought of given how function-proc-macros operate):
Proc-macro attributes and derives get their own pages, with a representative declaration block. Derive macros also show off their helper attributes:
There's one wrinkle which this PR doesn't address, which is why i didn't mark this as fixing the linked issue. Currently, proc-macros don't expose their attributes or source span across crates, so while rustdoc knows they exist, that's about all the information it gets. This leads to an "inlined" macro that has absolutely no docs on it, and no `[src]` link to show you where it was declared.
The way i got around it was to keep proc-macro re-export disabled, since we do get enough information across crates to properly link to the source page:
Until we can get a proc-macro's docs (and ideally also its source span) across crates, i believe this is the best way forward.
constraints:
- clean/inline.rs needs this map to fill in traits when inlining
- fold.rs needs this map to allow passes to fold trait items
- html/render.rs needs this map to seed the Cache.traits map of all
known traits
The first two are the real problem, since `DocFolder` only operates on
`clean::Crate` but `clean/inline.rs` only sees the `DocContext`. The
introduction of early passes means that these two now exist at the same
time, so they need to share ownership of the map. Even better, the use
of `Crate` in a rustc thread pool means that it needs to be Sync, so it
can't use `Lrc<Lock>` to manually activate thread-safety.
`parking_lot` is reused from elsewhere in the tree to allow use of its
`ReentrantMutex`, as the relevant parts of rustdoc are still
single-threaded and this allows for easier use in that context.
rustdoc: add flag to control the html_root_url of dependencies
The `--extern-html-root-url` flag in this PR allows one to override links to crates whose docs are not already available locally in the doc bundle. Docs.rs currently uses a version of this to make sure links to other crates go into that crate's docs.rs page. See the included test for intended use, but the idea is as follows:
Calling rustdoc with `--extern-html-root-url crate=https://some-url.com` will cause rustdoc to override links that point to that crate to instead be replaced with a link rooted at `https://some-url.com/`. (e.g. for docs.rs this would be `https://docs.rs/crate/0.1.0` or the like.) Cheekily, rustup could use these options to redirect links to std/core/etc to instead point to locally-downloaded docs, if it so desired.
Fixes https://github.com/rust-lang/rust/issues/19603
