Assoc item cleanup Part 2
- Remove `AssocItem` from `RegionVariableOrigin::AutoRef`
- Use the `associated_item_def_ids` query instead of the `associated_items` query when possible
The change to `ObligationCauseCode` from #90639 is omitted because it caused a perf regression.
r? `@cjgillot`
stabilize format args capture
Works as expected, and there are widespread reports of success with it, as well as interest in it.
RFC: rust-lang/rfcs#2795
Tracking issue: https://github.com/rust-lang/rust/issues/67984
Addressing items from the tracking issue:
- We don't support capturing arguments from a non-literal format string like `format_args!(concat!(...))`. We could add that in a future enhancement, or we can decide that it isn't supported (as suggested in https://github.com/rust-lang/rust/issues/67984#issuecomment-801394736 ).
- I've updated the documentation.
- `panic!` now supports capture as well.
- There are potentially opportunities to further improve diagnostics for invalid usage, such as if it looks like the user tried to use an expression rather than a variable. However, such cases are all already caught and provide reasonable syntax errors now, and we can always provided even friendlier diagnostics in the future.
Implement diagnostic for String conversion
This is my first real contribution to rustc, any feedback is highly appreciated.
This should fix https://github.com/rust-lang/rust/issues/89856
Thanks to `@estebank` for guiding me.
check if `String` or `&String` or `&str`
Update compiler/rustc_typeck/src/check/method/suggest.rs
Co-authored-by: Esteban Kuber <estebank@users.noreply.github.com>
remove some trailing whitespace
Fix trait object error code
closes#90768
I `grep`:d and changed the occurrences that seemed relevant. Please let me know what you think and if anything is missing!
implement rfc-2528 type_changing-struct-update
This PR implement rfc2528-type_changing-struct-update.
The main change process is as follows:
1. Move the processing part of `base_expr` into `check_expr_struct_fields` to avoid returning `remaining_fields` (a relatively complex hash table)
2. Before performing the type consistency check(`check_expr_has_type_or_error`), if the `type_changing_struct_update` feature is set, enter a different processing flow, otherwise keep the original flow
3. In the case of the same structure definition, check each field in `remaining_fields`. If the field in `base_expr` is not the suptype of the field in `adt_ty`, an error(`FeildMisMatch`) will be reported.
The MIR part does not need to be changed, because only the items contained in `remaining_fields` will be extracted from `base_expr` when MIR is generated. This means that fields with different types in `base_expr` will not be used
Updates #86618
cc `@nikomatsakis`
Type inference for inline consts
Fixes#78132Fixes#78174Fixes#81857Fixes#89964
Perform type checking/inference of inline consts in the same context as the outer def, similar to what is currently done to closure.
Doing so would require `closure_base_def_id` of the inline const to return the outer def, and since `closure_base_def_id` can be called on non-local crate (and thus have no HIR available), a new `DefKind` is created for inline consts.
The type of the generated anon const can capture lifetime of outer def, so we couldn't just use the typeck result as the type of the inline const's def. Closure has a similar issue, and it uses extra type params `CK, CS, U` to capture closure kind, input/output signature and upvars. I use a similar approach for inline consts, letting it have an extra type param `R`, and then `typeof(InlineConst<[paremt generics], R>)` would just be `R`. In borrowck region requirements are also propagated to the outer MIR body just like it's currently done for closure.
With this PR, inline consts in expression position are quitely usable now; however the usage in pattern position is still incomplete -- since those does not remain in the MIR borrowck couldn't verify the lifetime there. I have left an ignored test as a FIXME.
Some disucssions can be found on [this Zulip thread](https://rust-lang.zulipchat.com/#narrow/stream/260443-project-const-generics/topic/inline.20consts.20typeck).
cc `````@spastorino````` `````@lcnr`````
r? `````@nikomatsakis`````
`````@rustbot````` label A-inference F-inline_const T-compiler
Make `select_*` methods return `Vec` for `TraitEngine`
This reduces some complexity as an empty vec means no errors and non-empty vec means errors occurred.
type error go brrrrrrrr
Fixes#90444
when we relate something like:
`fn(fn((), (), u32))` with `fn(fn((), (), ()))`
we relate the inner fn ptrs:
`fn((), (), u32)` with `fn((), (), ())`
yielding a `TypeError::ArgumentSorts(_, 2)` which we then use as the `TypeError` for the `fn(fn(..))` which later causes the ICE as the `2` does not correspond to any input or output types in `fn(_)`
r? `@estebank`
Suggest dereference of `Box` when inner type is expected
For example:
enum Ty {
Unit,
List(Box<Ty>),
}
fn foo(x: Ty) -> Ty {
match x {
Ty::Unit => Ty::Unit,
Ty::List(elem) => foo(elem),
}
}
Before, the only suggestion was to rewrap `inner` with `Ty::Wrapper`,
which is unhelpful and confusing:
error[E0308]: mismatched types
--> src/test/ui/suggestions/boxed-variant-field.rs:9:31
|
9 | Ty::List(elem) => foo(elem),
| ^^^^
| |
| expected enum `Ty`, found struct `Box`
| help: try using a variant of the expected enum: `Ty::List(elem)`
|
= note: expected enum `Ty`
found struct `Box<Ty>`
Now, rustc will first suggest dereferencing the `Box`, which is most
likely what the user intended:
error[E0308]: mismatched types
--> src/test/ui/suggestions/boxed-variant-field.rs:9:31
|
9 | Ty::List(elem) => foo(elem),
| ^^^^ expected enum `Ty`, found struct `Box`
|
= note: expected enum `Ty`
found struct `Box<Ty>`
help: try dereferencing the `Box`
|
9 | Ty::List(elem) => foo(*elem),
| +
help: try using a variant of the expected enum
|
9 | Ty::List(elem) => foo(Ty::List(elem)),
| ~~~~~~~~~~~~~~
r? ``@davidtwco``
Apply adjustments for field expression even if inaccessible
The adjustments are used later by ExprUseVisitor to build Place projections and without adjustments it can produce invalid result.
Fix#90483
``@rustbot`` label: T-compiler
For example:
enum Ty {
Unit,
List(Box<Ty>),
}
fn foo(x: Ty) -> Ty {
match x {
Ty::Unit => Ty::Unit,
Ty::List(elem) => foo(elem),
}
}
Before, the only suggestion was to rewrap `elem` with `Ty::List`,
which is unhelpful and confusing:
error[E0308]: mismatched types
--> src/test/ui/suggestions/boxed-variant-field.rs:9:31
|
9 | Ty::List(elem) => foo(elem),
| ^^^^
| |
| expected enum `Ty`, found struct `Box`
| help: try using a variant of the expected enum: `Ty::List(elem)`
|
= note: expected enum `Ty`
found struct `Box<Ty>`
Now, rustc will first suggest dereferencing the `Box`, which is most
likely what the user intended:
error[E0308]: mismatched types
--> src/test/ui/suggestions/boxed-variant-field.rs:9:31
|
9 | Ty::List(elem) => foo(elem),
| ^^^^ expected enum `Ty`, found struct `Box`
|
= note: expected enum `Ty`
found struct `Box<Ty>`
help: try dereferencing the `Box`
|
9 | Ty::List(elem) => foo(*elem),
| +
help: try using a variant of the expected enum
|
9 | Ty::List(elem) => foo(Ty::List(elem)),
| ~~~~~~~~~~~~~~
Implementation of GATs outlives lint
See #87479 for background. Closes#87479
The basic premise of this lint/error is to require the user to write where clauses on a GAT when those bounds can be implied or proven from any function on the trait returning that GAT.
## Intuitive Explanation (Attempt) ##
Let's take this trait definition as an example:
```rust
trait Iterable {
type Item<'x>;
fn iter<'a>(&'a self) -> Self::Item<'a>;
}
```
Let's focus on the `iter` function. The first thing to realize is that we know that `Self: 'a` because of `&'a self`. If an impl wants `Self::Item` to contain any data with references, then those references must be derived from `&'a self`. Thus, they must live only as long as `'a`. Furthermore, because of the `Self: 'a` implied bound, they must live only as long as `Self`. Since it's `'a` is used in place of `'x`, it is reasonable to assume that any value of `Self::Item<'x>`, and thus `'x`, will only be able to live as long as `Self`. Therefore, we require this bound on `Item` in the trait.
As another example:
```rust
trait Deserializer<T> {
type Out<'x>;
fn deserialize<'a>(&self, input: &'a T) -> Self::Out<'a>;
}
```
The intuition is similar here, except rather than a `Self: 'a` implied bound, we have a `T: 'a` implied bound. Thus, the data on `Self::Out<'a>` is derived from `&'a T`, and thus it is reasonable to expect that the lifetime `'x` will always be less than `T`.
## Implementation Algorithm ##
* Given a GAT `<P0 as Trait<P1..Pi>>::G<Pi...Pn>` declared as `trait T<A1..Ai> for A0 { type G<Ai...An>; }` used in return type of one associated function `F`
* Given env `E` (including implied bounds) for `F`
* For each lifetime parameter `'a` in `P0...Pn`:
* For each other type parameter `Pi != 'a` in `P0...Pn`: // FIXME: this include of lifetime parameters too
* If `E => (P: 'a)`:
* Require where clause `Ai: 'a`
## Follow-up questions ##
* What should we do when we don't pass params exactly?
For this example:
```rust
trait Des {
type Out<'x, D>;
fn des<'z, T>(&self, data: &'z Wrap<T>) -> Self::Out<'z, Wrap<T>>;
}
```
Should we be requiring a `D: 'x` clause? We pass `Wrap<T>` as `D` and `'z` as `'x`, and should be able to prove that `Wrap<T>: 'z`.
r? `@nikomatsakis`
