Avoid invoking the hir_crate query to traverse the HIR
Walking the HIR tree is done using the `hir_crate` query. However, this is unnecessary, since `hir_owner(CRATE_DEF_ID)` provides the same information. Since depending on `hir_crate` forces dependents to always be executed, this leads to unnecessary work.
By splitting HIR and attributes visits, we can avoid an edge to `hir_crate` when trying to visit the HIR tree.
rustdoc: Clean up handling of lifetime bounds
Previously, rustdoc recorded lifetime bounds by rendering them into the
name of the lifetime parameter. Now, it leaves the name as the actual
name and instead records lifetime bounds in an `outlives` list, similar
to how type parameter bounds are recorded.
Also, higher-ranked lifetimes cannot currently have bounds, so I simplified
the code to reflect that.
r? `@GuillaumeGomez`
rustdoc: Box `GenericArg::Const` to reduce enum size
This should reduce the amount of memory allocated in the common cases
where the `GenericArg` is a lifetime or type.
This cleans up the other spot I found where rustdoc was rendering bounds
into the lifetime name itself. However, in this case, I don't think it
could have actually happened because higher-ranked lifetime definitions
aren't currently allowed to have bounds.
Previously, rustdoc recorded lifetime bounds by rendering them into the
name of the lifetime parameter. Now, it leaves the name as the actual
name and instead records lifetime bounds in an `outlives` list, similar
to how type parameter bounds are recorded.
rustdoc: Don't panic on ambiguous inherent associated types
Instead, return `Type::Infer` since compilation should fail anyway.
That's how rustdoc handles `hir::TyKind::Err`s, so this just extends
that behavior to `ty::Err`s when analyzing associated types.
For some reason, the error is printed twice with rustdoc (though only
once with rustc). I'm not sure why that is, but it's better than
panicking.
This commit also makes rustdoc fail early in the non-projection,
non-error case, instead of returning a `Res::Err` that would likely
cause rustdoc to panic later on. This change is originally from #88379.
r? `@GuillaumeGomez`
rustdoc: Box `GenericArgs::Parenthesized.output`
Split out from #88379.
This reduces the size of `GenericArgs` from 104 bytes to 56 bytes,
essentially reducing it by half.
`GenericArgs` is one of the fields of `PathSegment`, so this should
reduce the amount of memory allocated for `PathSegment`s in the cases
where the generics are not for a `Fn`, `FnMut`, or `FnOnce` trait.
r? `@jyn514`
Instead, return `Type::Infer` since compilation should fail anyway.
That's how rustdoc handles `hir::TyKind::Err`s, so this just extends
that behavior to `ty::Err`s when analyzing associated types.
For some reason, the error is printed twice with rustdoc (though only
once with rustc). I'm not sure why that is, but it's better than
panicking.
This commit also makes rustdoc fail early in the non-projection,
non-error case, instead of returning a `Res::Err` that would likely
cause rustdoc to panic later on. This change is originally from #88379.
Display associated types of implementors
Fixes#86631.
Contrary to before, it doesn't display methods. I also had to "resurrect" the `auto-hide-trait-implementations` setting. :3
Only question at this point: should I move the `render_impl` boolean arguments into one struct? We're starting to have quite a lot of them...
cc `@cynecx`
r? `@camelid`
This reduces the size of `GenericArgs` from 104 bytes to 56 bytes,
essentially reducing it by half.
`GenericArgs` is one of the fields of `PathSegment`, so this should
reduce the amount of memory allocated for `PathSegment`s in the cases
where the generics are not for a `Fn`, `FnMut`, or `FnOnce` trait.
I also added `static_assert_size!`s to `GenericArgs` and `PathSegment`
to ensure they don't increase in size unexpectedly.
Fix: don't document private macros by default
As part of #88019, I made it so private macros are documented in `--document-private-items` mode. Unfortunately, it appears that I also accidentally made them be documented when *not* in `--document-private-items` mode. This PR fixes that and adds a regression test.
r? `@jyn514` (I hope you don't mind that I keep sending PRs your way)
Fixes#88453.
Refactor Markdown length-limited summary implementation
This PR is a new approach to #79749.
This PR refactors the implementation of `markdown_summary_with_limit()`,
separating the logic of determining when the limit has been reached from
the actual rendering process.
The main advantage of the new approach is that it guarantees that all
HTML tags are closed, whereas the previous implementation could generate
tags that were never closed. It also ensures that no empty tags are
generated (e.g., `<em></em>`).
The new implementation consists of a general-purpose struct
`HtmlWithLimit` that manages the length-limiting logic and a function
`markdown_summary_with_limit()` that renders Markdown to HTML using the
struct.
r? `@GuillaumeGomez`
- [x] Removed `?const` and change uses of `?const`
- [x] Added `~const` to the AST. It is gated behind const_trait_impl.
- [x] Validate `~const` in ast_validation.
- [ ] Add enum `BoundConstness` to the HIR. (With variants `NotConst` and
`ConstIfConst` allowing future extensions)
- [ ] Adjust trait selection and pre-existing code to use `BoundConstness`.
- [ ] Optional steps (*for this PR, obviously*)
- [ ] Fix#88155
- [ ] Do something with constness bounds in chalk
lazily "compute" anon const default substs
Continuing the work of #83086, this implements the discussed solution for the [unused substs problem](https://github.com/rust-lang/project-const-generics/blob/master/design-docs/anon-const-substs.md#unused-substs). As of now, anonymous constants inherit all of their parents generics, even if they do not use them, e.g. in `fn foo<T, const N: usize>() -> [T; N + 1]`, the array length has `T` as a generic parameter even though it doesn't use it. These *unused substs* cause some backwards incompatible, and imo incorrect behavior, e.g. #78369.
---
We do not actually filter any generic parameters here and the `default_anon_const_substs` query still a dummy which only checks that
- we now prevent the previously existing query cycles and are able to call `predicates_of(parent)` when computing the substs of anonymous constants
- the default anon consts substs only include the typeflags we assume it does.
Implementing that filtering will be left as future work.
---
The idea of this PR is to delay the creation of the anon const substs until after we've computed `predicates_of` for the parent of the anon const. As the predicates of the parent can however contain the anon const we still have to create a `ty::Const` for it.
We do this by changing the substs field of `ty::Unevaluated` to an option and modifying accesses to instead call the method `unevaluated.substs(tcx)` which returns the substs as before. If the substs - now `substs_` - of `ty::Unevaluated` are `None`, it means that the anon const currently has its default substs, i.e. the substs it has when first constructed, which are the generic parameters it has available. To be able to call `unevaluated.substs(tcx)` in a `TypeVisitor`, we add the non-defaulted method `fn tcx_for_anon_const_substs(&self) -> Option<TyCtxt<'tcx>>`. In case `tcx_for_anon_const_substs` returns `None`, unknown anon const default substs are skipped entirely.
Even when `substs_` is `None` we still have to treat the constant as if it has its default substs. To do this, `TypeFlags` are modified so that it is clear whether they can still change when *exposing* any anon const default substs. A new flag, `HAS_UNKNOWN_DEFAULT_CONST_SUBSTS`, is added in case some default flags are missing.
The rest of this PR are some smaller changes to either not cause cycles by trying to access the default anon const substs too early or to be able to access the `tcx` in previously unused locations.
cc `@rust-lang/project-const-generics`
r? `@nikomatsakis`
- All attributes for an item need to be considered at once, they can't
be considered a line at a time.
- The top-level crate was not being visited. This bug was caught by
`extern-crate-used-only-in-link`, which I'm very glad I added.
- Make the loader private to the module, so that only one function is
exposed.
This can happen when a tag is opened after the length limit is reached;
the tag will not end up being added to `unclosed_tags` because the queue
will never be flushed. So, now, if the `unclosed_tags` stack is empty,
`close_tag()` does nothing.
This change fixes a panic in the `limit_0` unit test.