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Diffstat (limited to '')
-rw-r--r-- | src/test/ui/type-alias-impl-trait/issue-65918.rs | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/src/test/ui/type-alias-impl-trait/issue-65918.rs b/src/test/ui/type-alias-impl-trait/issue-65918.rs new file mode 100644 index 000000000..af6d50109 --- /dev/null +++ b/src/test/ui/type-alias-impl-trait/issue-65918.rs @@ -0,0 +1,51 @@ +// ignore-test: This now ICEs again. + +// build-pass + +#![feature(type_alias_impl_trait)] + +use std::marker::PhantomData; + +/* copied Index and TryFrom for convenience (and simplicity) */ +trait MyIndex<T> { + type O; + fn my_index(self) -> Self::O; +} +trait MyFrom<T>: Sized { + type Error; + fn my_from(value: T) -> Result<Self, Self::Error>; +} + +/* MCVE starts here */ +trait F {} +impl F for () {} +type DummyT<T> = impl F; +fn _dummy_t<T>() -> DummyT<T> {} + +struct Phantom1<T>(PhantomData<T>); +struct Phantom2<T>(PhantomData<T>); +struct Scope<T>(Phantom2<DummyT<T>>); + +impl<T> Scope<T> { + fn new() -> Self { + unimplemented!() + } +} + +impl<T> MyFrom<Phantom2<T>> for Phantom1<T> { + type Error = (); + fn my_from(_: Phantom2<T>) -> Result<Self, Self::Error> { + unimplemented!() + } +} + +impl<T: MyFrom<Phantom2<DummyT<U>>>, U> MyIndex<Phantom1<T>> for Scope<U> { + type O = T; + fn my_index(self) -> Self::O { + MyFrom::my_from(self.0).ok().unwrap() + } +} + +fn main() { + let _pos: Phantom1<DummyT<()>> = Scope::new().my_index(); +} |