Add fuel to match checking
Exhaustiveness checking is NP-hard hence can take extremely long to check some specific matches. This PR makes ehxaustiveness bail after a set number of steps. I chose a bound that takes ~100ms on my machine, which should be more than enough for normal matches.
I'd like someone with less recent hardware to run the test to see if that limit is low enough for them. Also curious if the r-a team thinks this is a good ballpark or if we should go lower/higher. I don't have much data on how complex real-life matches get, but we can definitely go lower than `500 000` steps.
The second commit is a drive-by soundness fix which doesn't matter much today but will matter once `min_exhaustive_patterns` is stabilized.
Fixes https://github.com/rust-lang/rust-analyzer/issues/9528 cc `@matklad`
feat: Implement ATPIT
Resolves#16584
Note: This implementation only works for ATPIT, not for TAIT.
The main hinderence that blocks the later is the defining sites of TAIT can be inner blocks like in;
```rust
type X = impl Default;
mod foo {
fn bar() -> super::X {
()
}
}
```
So, to figure out we are defining it or not, we should recursively probe for nested modules and bodies.
For ATPIT, we can just look into current body because `error[E0401]: can't use 'Self' from outer item` prevent such nested structures;
```rust
trait Foo {
type Item;
fn foo() -> Self::Item;
}
struct Bar;
impl Foo for Bar {
type Item = impl Default;
fn foo() -> Self::Item {
fn bar() -> Self::Item {
^^^^^^^^^^
|
use of `Self` from outer item
refer to the type directly here instead
5
}
bar()
}
}
```
But this implementation does not checks for unification of same ATPIT between different bodies, monomorphization, nor layout for similar reason. (But these can be done with lazyness if we can utilize something like "mutation of interned value" with `db`. I coundn't find such thing but I would appreciate it if such thing exists and you could let me know 😅)
Bump dependencies and use in-tree `rustc_pattern_analysis`
One last `pattern_analysis` API change. I don't have any more planned! So we can now use the in-tree version when available.
internal: Compress file text using LZ4
I haven't tested properly, but this roughly looks like:
```
1246 MB
59mb 4899 FileTextQuery
1008 MB
20mb 4899 CompressedFileTextQuery
555kb 1790 FileTextQuery
```
We might want to test on something more interesting, like `bevy`.
From `impl Into<DiagnosticMessage>` to `impl Into<Cow<'static, str>>`.
Because these functions don't produce user-facing output and we don't
want their strings to be translated.
fix: Wrong closure kind deduction for closures with predicates
Completes #16472, fixes#16421
The changed closure kind deduction is mostly simlar to `rustc_hir_typeck/src/closure.rs`.
Porting closure sig deduction from it seems possible too and I'm considering doing it with another PR
