rustdoc: Preserve rendering of macro_rules matchers when possible
Fixes#92331. This approach restores the behavior prior to #86282 **if** the matcher token held by the compiler **and** the matcher token found in the source code are identical TokenTrees. Thus #86208 remains fixed, but without regressing formatting for the vast majority of macros which are not macro-generated.
Rustdoc: use ThinVec for GenericArgs bindings
The bindings are almost always empty. This reduces the size of `PathSegment` and `GenericArgs` by about one fourth.
Remove `SymbolStr`
This was originally proposed in https://github.com/rust-lang/rust/pull/74554#discussion_r466203544. As well as removing the icky `SymbolStr` type, it allows the removal of a lot of `&` and `*` occurrences.
Best reviewed one commit at a time.
r? `@oli-obk`
`render/context` always runs after `run_global_context`, so it was always set to `true`.
This is a holdover from when rustdoc allowed configuring passes, but the `collapse-docs` pass was
removed ages ago, and the ability to configure passes is about to be removed.
I would like to rename it to `Type::Path`, but then it can't be
re-exported since the name would conflict with the `Path` struct.
Usually enum variants are referred to using their qualified names in
Rust (and parts of rustdoc already do that with `clean::Type`), so this
is also more consistent with the language.
Before, if `register_res` were called on an associated item or enum
variant, it would return the parent's `DefId`. Now, it returns the
actual `DefId`.
This change is a step toward removing `Type::ResolvedPath.did` and
potentially removing `kind_side_channel` in rustdoc. It also just
simplifies rustdoc's behavior.
It is only used in one place; `src` was about a third of `Crate`'s total
size; `Crate` is frequently moved by-value; and `src` can be easily
computed on-demand.
The change to `impl Clean<Path> for hir::TraitRef<'_>` was necessary to
fix a test failure for `src/test/rustdoc/trait-alias-mention.rs`.
Here's why:
The old code path was through `impl Clean<Type> for hir::TraitRef<'_>`,
which called `resolve_type`, which in turn called `register_res`. Now,
because `PolyTrait` uses a `Path` instead of a `Type`, the impl of
`Clean<Path>` was being run, which did not call `register_res`, causing
the trait alias to not be recorded in the `external_paths` cache.
It was only used for sugaring `Fn` trait bounds, and rustdoc already
checks that the `did` is for a `Fn` (or `FnMut`, `FnOnce`) lang item,
so it's not necessary to also check that the `did` belongs to a trait.
The order of the `where` bounds on auto trait impls changed because
rustdoc currently sorts auto trait `where` bounds based on the `Debug`
output for the bound. Now that the bounds have an actual `Res`, they are
being unintentionally sorted by their `DefId` rather than their path.
So, I had to update a test for the change in ordering of the rendered
bounds.
