Specifically `TyAlias`, `Enum`, `Struct`, `Union`. So the fields match
the textual order in the source code.
The interesting part of the change is in
`compiler/rustc_hir/src/hir.rs`. The rest is extremely mechanical
refactoring.
Defer evaluating type system constants when they use infers or params
Split out of #137972, the parts necessary for associated const equality and min generic const args to make progress and have correct semantics around when CTFE is invoked. According to a [previous perf run](https://perf.rust-lang.org/compare.html?start=93257e2d20809d82d1bc0fcc1942480d1a66d7cd&end=01b4cbf0f47c3f782330db88fa5ba199bba1f8a2&stat=instructions:u) of adding the new `const_arg_kind` query we should expect minor regressions here.
I think this is acceptable as we should be able to remove this query relatively soon once mgca is more complete as we'll then be able to implement GCE in terms of mgca and rip out `GCEConst` at which point it's trivial to determine what kind of anon const we're dealing with (either it has generics and is a repeat expr hack, or it doesnt and is a normal anon const).
This should only affect unstable code as we handle repeat exprs specially and those are the only kinds of type system consts that are allowed to make use of generic parameters.
Fixes#133066Fixes#133199Fixes#136894Fixes#137813
r? compiler-errors
`hir::AssocItem` currently has a boolean `fn_has_self_parameter` field,
which is misplaced, because it's only relevant for associated fns, not
for associated consts or types. This commit moves it (and renames it) to
the `AssocKind::Fn` variant, where it belongs.
This requires introducing a new C-style enum, `AssocTag`, which is like
`AssocKind` but without the fields. This is because `AssocKind` values
are passed to various functions like `find_by_ident_and_kind` to
indicate what kind of associated item should be searched for, and having
to specify `has_self` isn't relevant there.
New methods:
- Predicates `AssocItem::is_fn` and `AssocItem::is_method`.
- `AssocItem::as_tag` which converts `AssocItem::kind` to `AssocTag`.
Removed `find_by_name_and_kinds`, which is unused.
`AssocItem::descr` can now distinguish between methods and associated
functions, which slightly improves some error messages.
Rename some `name` variables as `ident`.
It bugs me when variables of type `Ident` are called `name`. It leads to silly things like `name.name`. `Ident` variables should be called `ident`, and `name` should be used for variables of type `Symbol`.
This commit improves things by by doing `s/name/ident/` on a bunch of `Ident` variables. Not all of them, but a decent chunk.
r? `@fee1-dead`
It bugs me when variables of type `Ident` are called `name`. It leads to
silly things like `name.name`. `Ident` variables should be called
`ident`, and `name` should be used for variables of type `Symbol`.
This commit improves things by by doing `s/name/ident/` on a bunch of
`Ident` variables. Not all of them, but a decent chunk.
`hir::Item` has an `ident` field.
- It's always non-empty for these item kinds: `ExternCrate`, `Static`,
`Const`, `Fn`, `Macro`, `Mod`, `TyAlias`, `Enum`, `Struct`, `Union`,
Trait`, TraitAalis`.
- It's always empty for these item kinds: `ForeignMod`, `GlobalAsm`,
`Impl`.
- For `Use`, it is non-empty for `UseKind::Single` and empty for
`UseKind::{Glob,ListStem}`.
All of this is quite non-obvious; the only documentation is a single
comment saying "The name might be a dummy name in case of anonymous
items". Some sites that handle items check for an empty ident, some
don't. This is a very C-like way of doing things, but this is Rust, we
have sum types, we can do this properly and never forget to check for
the exceptional case and never YOLO possibly empty identifiers (or
possibly dummy spans) around and hope that things will work out.
The commit is large but it's mostly obvious plumbing work. Some notable
things.
- A similar transformation makes sense for `ast::Item`, but this is
already a big change. That can be done later.
- Lots of assertions are added to item lowering to ensure that
identifiers are empty/non-empty as expected. These will be removable
when `ast::Item` is done later.
- `ItemKind::Use` doesn't get an `Ident`, but `UseKind::Single` does.
- `lower_use_tree` is significantly simpler. No more confusing `&mut
Ident` to deal with.
- `ItemKind::ident` is a new method, it returns an `Option<Ident>`. It's
used with `unwrap` in a few places; sometimes it's hard to tell
exactly which item kinds might occur. None of these unwraps fail on
the test suite. It's conceivable that some might fail on alternative
input. We can deal with those if/when they happen.
- In `trait_path` the `find_map`/`if let` is replaced with a loop, and
things end up much clearer that way.
- `named_span` no longer checks for an empty name; instead the call site
now checks for a missing identifier if necessary.
- `maybe_inline_local` doesn't need the `glob` argument, it can be
computed in-function from the `renamed` argument.
- `arbitrary_source_item_ordering::check_mod` had a big `if` statement
that was just getting the ident from the item kinds that had one. It
could be mostly replaced by a single call to the new `ItemKind::ident`
method.
- `ItemKind` grows from 56 to 64 bytes, but `Item` stays the same size,
and that's what matters, because `ItemKind` only occurs within `Item`.
make precise capturing args in rustdoc Json typed
close#137616
This PR includes below changes.
- Add `rustc_hir::PreciseCapturingArgKind` which allows the query system to return a arg's data.
- Add `rustdoc::clean::types::PreciseCapturingArg` and change to use it.
- Add `rustdoc-json-types::PreciseCapturingArg` and change to use it.
- Update `tests/rustdoc-json/impl-trait-precise-capturing.rs`.
- Bump `rustdoc_json_types::FORMAT_VERSION`.
Continuing the work from #137350.
Removes the unused methods: `expect_variant`, `expect_field`,
`expect_foreign_item`.
Every method gains a `hir_` prefix.
When `#![feature(min_generic_const_args)]` is enabled, we now lower all
const paths in generic arg position to `hir::ConstArgKind::Path`. We
then lower assoc const paths to `ty::ConstKind::Unevaluated` since we
can no longer use the anon const expression lowering machinery. In the
process of implementing this, I factored out `hir_ty_lowering` code that
is now shared between lowering assoc types and assoc consts.
This PR also introduces a `#[type_const]` attribute for trait assoc
consts that are allowed as const args. However, we still need to
implement code to check that assoc const definitions satisfy
`#[type_const]` if present (basically is it a const path or a
monomorphic anon const).
Greatly simplify lifetime captures in edition 2024
Remove most of the `+ Captures` and `+ '_` from the compiler, since they are now unnecessary with the new edition 2021 lifetime capture rules. Use some `+ 'tcx` and `+ 'static` rather than being overly verbose with precise capturing syntax.
First of all, note that `Map` has three different relevant meanings.
- The `intravisit::Map` trait.
- The `map::Map` struct.
- The `NestedFilter::Map` associated type.
The `intravisit::Map` trait is impl'd twice.
- For `!`, where the methods are all unreachable.
- For `map::Map`, which gets HIR stuff from the `TyCtxt`.
As part of getting rid of `map::Map`, this commit changes `impl
intravisit::Map for map::Map` to `impl intravisit::Map for TyCtxt`. It's
fairly straightforward except various things are renamed, because the
existing names would no longer have made sense.
- `trait intravisit::Map` becomes `trait intravisit::HirTyCtxt`, so named
because it gets some HIR stuff from a `TyCtxt`.
- `NestedFilter::Map` assoc type becomes `NestedFilter::MaybeTyCtxt`,
because it's always `!` or `TyCtxt`.
- `Visitor::nested_visit_map` becomes `Visitor::maybe_tcx`.
I deliberately made the new trait and associated type names different to
avoid the old `type Map: Map` situation, which I found confusing. We now
have `type MaybeTyCtxt: HirTyCtxt`.
The end goal is to eliminate `Map` altogether.
I added a `hir_` prefix to all of them, that seemed simplest. The
exceptions are `module_items` which became `hir_module_free_items` because
there was already a `hir_module_items`, and `items` which became
`hir_free_items` for consistency with `hir_module_free_items`.
```
error[E0109]: type arguments are not allowed on enum `Enum` and tuple variant `TSVariant`
--> $DIR/enum-variant-generic-args.rs:54:12
|
LL | Enum::<()>::TSVariant::<()>(());
| ---- ^^ --------- ^^ type argument not allowed
| | |
| | not allowed on tuple variant `TSVariant`
| not allowed on enum `Enum`
|
= note: generic arguments are not allowed on both an enum and its variant's path segments simultaneously; they are only valid in one place or the other
help: remove the generics arguments from one of the path segments
|
LL - Enum::<()>::TSVariant::<()>(());
LL + Enum::<()>::TSVariant(());
|
```
Fix#93993.
Instead re-export `rustc_hir_analysis::collect::suggest_impl_trait`,
which is the only thing from the module used in another crate. This
fixes a `FIXME` comment. Also adjust some visibilities to satisfy the
`unreachable_pub` lint.
This changes requires downgrading a link in a comment on `FnCtxt`
because `collect` is no longer public and rustdoc complains otherwise.
This is annoying but I can't see how to avoid it.
Always lower to `GenericArg::Infer`
Update `PlaceholderCollector`
Update closure lifetime binder infer var visitor
Fallback visitor handle ambig infer args
Ensure type infer args have their type recorded
rustc_intrinsic: support functions without body
We synthesize a HIR body `loop {}` but such bodyless intrinsics.
Most of the diff is due to turning `ItemKind::Fn` into a brace (named-field) enum variant, because it carries a `bool`-typed field now. This is to remember whether the function has a body. MIR building panics to avoid ever translating the fake `loop {}` body, and the intrinsic logic uses the lack of a body to implicitly mark that intrinsic as must-be-overridden.
I first tried actually having no body rather than generating the fake body, but there's a *lot* of code that assumes that all function items have HIR and MIR, so this didn't work very well. Then I noticed that even `rustc_intrinsic_must_be_overridden` intrinsics have MIR generated (they are filled with an `Unreachable` terminator) so I guess I am not the first to discover this. ;)
r? `@oli-obk`