Encode def span for foreign return-position `impl Trait` in trait
Fixes#111031, yet another def-span encoding issue :/
Includes a smaller repro than the issue, but I can confirm it ICEs:
```
query stack during panic:
#0 [def_span] looking up span for `rpitit::Foo::bar::{opaque#0}`
#1 [object_safety_violations] determining object safety of trait `rpitit::Foo`
#2 [check_is_object_safe] checking if trait `rpitit::Foo` is object safe
#3 [typeck] type-checking `main`
#4 [used_trait_imports] finding used_trait_imports `main`
#5 [analysis] running analysis passes on this crate
```
Luckily since this only affects nightly, this desn't need to be backported.
Do not consider synthesized RPITITs on missing items checks
Without this patch for `tests/ui/impl-trait/in-trait/dont-project-to-rpitit-with-no-value.rs` we get ...
```
warning: the feature `return_position_impl_trait_in_trait` is incomplete and may not be safe to use and/or cause compiler crashes
--> tests/ui/impl-trait/in-trait/dont-project-to-rpitit-with-no-value.rs:4:12
|
4 | #![feature(return_position_impl_trait_in_trait)]
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= note: see issue #91611 <https://github.com/rust-lang/rust/issues/91611> for more information
= note: `#[warn(incomplete_features)]` on by default
error[E0046]: not all trait items implemented, missing: `foo`, ``
--> tests/ui/impl-trait/in-trait/dont-project-to-rpitit-with-no-value.rs:12:1
|
8 | fn foo(&self) -> impl Sized;
| ----------------------------
| | |
| | `` from trait
| `foo` from trait
...
12 | impl MyTrait for i32 {
| ^^^^^^^^^^^^^^^^^^^^ missing `foo`, `` in implementation
error: aborting due to previous error; 1 warning emitted
For more information about this error, try `rustc --explain E0046`.
```
instead of ...
```
warning: the feature `return_position_impl_trait_in_trait` is incomplete and may not be safe to use and/or cause compiler crashes
--> $DIR/dont-project-to-rpitit-with-no-value.rs:4:12
|
LL | #![feature(return_position_impl_trait_in_trait)]
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= note: see issue #91611 <https://github.com/rust-lang/rust/issues/91611> for more information
= note: `#[warn(incomplete_features)]` on by default
error[E0046]: not all trait items implemented, missing: `foo`
--> $DIR/dont-project-to-rpitit-with-no-value.rs:12:1
|
LL | fn foo(&self) -> impl Sized;
| ---------------------------- `foo` from trait
...
LL | impl MyTrait for i32 {
| ^^^^^^^^^^^^^^^^^^^^ missing `foo` in implementation
error: aborting due to previous error; 1 warning emitted
For more information about this error, try `rustc --explain E0046`.
```
r? `@compiler-errors`
Walk un-shifted nested `impl Trait` in trait when setting up default trait method assumptions
Fixes a double subtraction in some binder math in return-position `impl Trait` in trait handling code.
Fixes#109239
Fix generics_of for impl's RPITIT synthesized associated type
The only useful commit is the last one.
This makes `generics_of` for the impl side RPITIT copy from the trait's associated type and avoid the fn on the impl side which was previously wrongly used.
This solution is better but we still need to fix resolution of the generated generics.
r? ``@compiler-errors``
Fix generics mismatch errors for RPITITs on -Zlower-impl-trait-in-trait-to-assoc-ty
This PR stops reporting errors due to different count of generics on the new synthesized associated types for RPITITs. Those were already reported when we compare the function on the triat with the function on the impl.
r? ``@compiler-errors``
Make fns from other crates with RPITIT work for -Zlower-impl-trait-in-trait-to-assoc-ty
Only the last two commits are meaningful.
r? `@compiler-errors`
Remove tests/ui/impl-trait/in-trait/new-lowering-strategy in favor of using revisions on existing tests
r? `@compiler-errors`
This one again sits on top of existing approved PRs and it still needs to add revisions to tests in `tests/ui/impl-trait/in-trait` as it only does so for async in traits.
Remove `identity_future` indirection
This was previously needed because the indirection used to hide some unexplained lifetime errors, which it turned out were related to the `min_choice` algorithm.
Removing the indirection also solves a couple of cycle errors, large moves and makes async blocks support the `#[track_caller]`annotation.
Fixes https://github.com/rust-lang/rust/issues/104826.
This was previously needed because the indirection used to hide some unexplained lifetime errors, which it turned out were related to the `min_choice` algorithm.
Removing the indirection also solves a couple of cycle errors, large moves and makes async blocks support the `#[track_caller]` annotation.
Account for binders correctly when adding default RPITIT method assumption
As of #108203, we install extra projection predicates into the param-env of a default trait method when it has return-position `impl Trait` (or is async).
The implementation didn't account for the fact that it's walking into and out of binders, so we just need to shift all the debruijn indices accordingly when constructing the projection predicates.
Fixes#108579
r? types
