src/test/ui/type-alias-impl-trait/issue-63355.rs

   1 #![feature(min_type_alias_impl_trait)]
   2 #![feature(type_alias_impl_trait)]
   3 #![allow(incomplete_features)]
   4
   5 pub trait Foo {}
   6
   7 pub trait Bar {
   8     type Foo: Foo;
   9
  10     fn foo() -> Self::Foo;
  11 }
  12
  13 pub trait Baz {
  14     type Foo: Foo;
  15     type Bar: Bar<Foo = Self::Foo>;
  16
  17     fn foo() -> Self::Foo;
  18     fn bar() -> Self::Bar;
  19 }
  20
  21 impl Foo for () {}
  22
  23 impl Bar for () {
  24     type Foo = FooImpl;
  25
  26     fn foo() -> Self::Foo {
  27         ()
  28     }
  29 }
  30
  31 // FIXME(#86731): The below is illegal use of `min_type_alias_impl_trait`
  32 // but the compiler doesn't report it, we should fix it.
  33 pub type FooImpl = impl Foo;
  34 pub type BarImpl = impl Bar<Foo = FooImpl>;
  35 //~^ ERROR: type mismatch resolving `<() as Bar>::Foo == ()`
  36
  37 impl Baz for () {
  38     type Foo = FooImpl;
  39     type Bar = BarImpl;
  40
  41     fn foo() -> Self::Foo {
  42         ()
  43     }
  44
  45     fn bar() -> Self::Bar {
  46         ()
  47     }
  48 }
  49
  50 fn main() {}