src/test/ui/type-alias-impl-trait/issue-63677-type-alias-coherence.rs

   1 // check-pass
   2 // Regression test for issue #63677 - ensure that
   3 // coherence checking can properly handle 'impl trait'
   4 // in type aliases
   5 // revisions: min_tait full_tait
   6 #![feature(min_type_alias_impl_trait)]
   7 #![cfg_attr(full_tait, feature(type_alias_impl_trait))]
   8 //[full_tait]~^ WARN incomplete
   9
  10 pub trait Trait {}
  11 pub struct S1<T>(T);
  12 pub struct S2<T>(T);
  13
  14 pub type T1 = impl Trait;
  15 pub type T2 = S1<T1>;
  16 pub type T3 = S2<T2>;
  17
  18 impl<T> Trait for S1<T> {}
  19 impl<T: Trait> S2<T> {}
  20 impl T3 {}
  21
  22 pub fn use_t1() -> T1 { S1(()) }
  23
  24 fn main() {}