Introduce `AliasKind::Inherent` for inherent associated types
Allows us to check (possibly generic) inherent associated types for well-formedness.
Type inference now also works properly.
Follow-up to #105961. Supersedes #108430.
Fixes#106722.
Fixes#108957.
Fixes#109768.
Fixes#109789.
Fixes#109790.
~Not to be merged before #108860 (`AliasKind::Weak`).~
CC `@jackh726`
r? `@compiler-errors`
`@rustbot` label T-types F-inherent_associated_types
enable `rust_2018_idioms` lint group for doctests
With this change, `rust_2018_idioms` lint group will be enabled for compiler/libstd doctests.
Resolves#106086Resolves#99144
Signed-off-by: ozkanonur <work@onurozkan.dev>
Support return-type bounds on associated methods from supertraits
Support `T: Trait<method(): Bound>` when `method` comes from a supertrait, aligning it with the behavior of associated type bounds (both equality and trait bounds).
The only wrinkle is that I have to extend `super_predicates_that_define_assoc_type` to look for *all* items, not just `AssocKind::Ty`. This will also be needed to support `feature(associated_const_equality)` as well, which is subtly broken when it comes to supertraits, though this PR does not fix those yet. There's a slight chance there's a perf regression here, in which case I guess I could split it out into a separate query.
Use fulfillment to check `Drop` impl compatibility
Use an `ObligationCtxt` to ensure that a `Drop` impl does not have stricter requirements than the ADT that it's implemented for, rather than using a `SimpleEqRelation` to (more or less) syntactically equate predicates on an ADT with predicates on an impl.
r? types
### Some background
The old code reads:
```rust
// An earlier version of this code attempted to do this checking
// via the traits::fulfill machinery. However, it ran into trouble
// since the fulfill machinery merely turns outlives-predicates
// 'a:'b and T:'b into region inference constraints. It is simpler
// just to look for all the predicates directly.
```
I'm not sure what this means, but perhaps in the 8 years since that this comment was written (cc #23638) it's gotten easier to process region constraints after doing fulfillment? I don't know how this logic differs from anything we do in the `compare_impl_item` module. Ironically, later on it says:
```rust
// However, it may be more efficient in the future to batch
// the analysis together via the fulfill (see comment above regarding
// the usage of the fulfill machinery), rather than the
// repeated `.iter().any(..)` calls.
```
Also:
* Removes `SimpleEqRelation` which was far too syntactical in its relation.
* Fixes#110557
Implement negative bounds for internal testing purposes
Implements partial support the `!` negative polarity on trait bounds. This is incomplete, but should allow us to at least be able to play with the feature.
Not even gonna consider them as a public-facing feature, but I'm implementing them because would've been nice to have in UI tests, for example in #110671.
Currently a `{D,Subd}iagnosticMessage` can be created from any type that
impls `Into<String>`. That includes `&str`, `String`, and `Cow<'static,
str>`, which are reasonable. It also includes `&String`, which is pretty
weird, and results in many places making unnecessary allocations for
patterns like this:
```
self.fatal(&format!(...))
```
This creates a string with `format!`, takes a reference, passes the
reference to `fatal`, which does an `into()`, which clones the
reference, doing a second allocation. Two allocations for a single
string, bleh.
This commit changes the `From` impls so that you can only create a
`{D,Subd}iagnosticMessage` from `&str`, `String`, or `Cow<'static,
str>`. This requires changing all the places that currently create one
from a `&String`. Most of these are of the `&format!(...)` form
described above; each one removes an unnecessary static `&`, plus an
allocation when executed. There are also a few places where the existing
use of `&String` was more reasonable; these now just use `clone()` at
the call site.
As well as making the code nicer and more efficient, this is a step
towards possibly using `Cow<'static, str>` in
`{D,Subd}iagnosticMessage::{Str,Eager}`. That would require changing
the `From<&'a str>` impls to `From<&'static str>`, which is doable, but
I'm not yet sure if it's worthwhile.
Switch to `EarlyBinder` for `explicit_item_bounds`
Part of the work to finish https://github.com/rust-lang/rust/issues/105779.
This PR adds `EarlyBinder` to the return type of the `explicit_item_bounds` query and removes `bound_explicit_item_bounds`.
r? `@compiler-errors` (hope it's okay to request you, since you reviewed #110299 and #110498😃)
Break up long function in trait selection error reporting + clean up nearby code
- Move blocks of code into their own functions
- Replace a few function argument types with their type aliases
- Create "AppendConstMessage" enum to replace a nested `Option`.
Clone region var origins instead of taking them in borrowck
Fixes an issue with the new solver where reporting a borrow-checker error ICEs because it calls `InferCtxt::evaluate_obligation`.
This also removes a handful of unnecessary `tcx.infer_ctxt().build()` calls that are only there to mitigate this same exact issue, but with the old solver.
Fixescompiler-errors/next-solver-hir-issues#12.
----
This implements `@aliemjay's` solution where we just don't *take* the region constraints, but clone them. This potentially makes it easier to write a bug about taking region constraints twice or never at all, but again, not many folks are touching this code.
Add `rustc_fluent_macro` to decouple fluent from `rustc_macros`
Fluent, with all the icu4x it brings in, takes quite some time to compile. `fluent_messages!` is only needed in further downstream rustc crates, but is blocking more upstream crates like `rustc_index`. By splitting it out, we allow `rustc_macros` to be compiled earlier, which speeds up `x check compiler` by about 5 seconds (and even more after the needless dependency on `serde_json` is removed from `rustc_data_structures`).
Delay a good path bug on drop for `TypeErrCtxt` (instead of a regular delayed bug)
r? `@lcnr`
Perhaps we should just delete the `Drop` impl altogether though?
Fixesrust-lang/rust-clippy#10645
`@matthiaskrgr:` I don't know how to make a clippy test for this. Any idea? Clippy's UI tests run with `-D warnings` and I have no idea how to switch it off to make a test that triggers this ICE in the clippy test suite 🤣
Fluent, with all the icu4x it brings in, takes quite some time to
compile. `fluent_messages!` is only needed in further downstream rustc
crates, but is blocking more upstream crates like `rustc_index`. By
splitting it out, we allow `rustc_macros` to be compiled earlier, which
speeds up `x check compiler` by about 5 seconds (and even more after the
needless dependency on `serde_json` is removed from
`rustc_data_structures`).
Spelling compiler
This is per https://github.com/rust-lang/rust/pull/110392#issuecomment-1510193656
I'm going to delay performing a squash because I really don't expect people to be perfectly happy w/ my changes, I really am a human and I really do make mistakes.
r? Nilstrieb
I'm going to be flying this evening, but I should be able to squash / respond to reviews w/in a day or two.
I tried to be careful about dropping changes to `tests`, afaict only two files had changes that were likely related to the changes for a given commit (this is where not having eagerly squashed should have given me an advantage), but, that said, picking things apart can be error prone.
Various minor Idx-related tweaks
Nothing particularly exciting here, but a couple of things I noticed as I was looking for more index conversions to simplify.
cc https://github.com/rust-lang/compiler-team/issues/606
r? `@WaffleLapkin`
Remove `TypeSuper{Foldable,Visitable}` impls for `Region`.
These traits exist so that folders/visitors can recurse into types of interest: binders, types, regions, predicates, and consts. But `Region` is non-recursive and cannot contain other types of interest, so its methods in these traits are trivial.
This commit inlines and removes those trivial methods.
r? `@compiler-errors`
These traits exist so that folders/visitors can recurse into types of
interest: binders, types, regions, predicates, and consts. But `Region`
is non-recursive and cannot contain other types of interest, so its
methods in these traits are trivial.
This commit inlines and removes those trivial methods.