Skip to content

Add some type-alias-impl-trait regression tests #68498

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Jan 26, 2020
Merged
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
27 changes: 27 additions & 0 deletions src/test/ui/type-alias-impl-trait/issue-57611-trait-alias.rs
Original file line number Diff line number Diff line change
@@ -0,0 +1,27 @@
// Regression test for issue #57611
// Ensures that we don't ICE
// FIXME: This should compile, but it currently doesn't

#![feature(trait_alias)]
#![feature(type_alias_impl_trait)]

trait Foo {
type Bar: Baz<Self, Self>;

fn bar(&self) -> Self::Bar;
}

struct X;

impl Foo for X {
type Bar = impl Baz<Self, Self>; //~ ERROR type mismatch in closure arguments
//~^ ERROR type mismatch resolving

fn bar(&self) -> Self::Bar {
|x| x
}
}

trait Baz<A, B> = Fn(&A) -> &B;

fn main() {}
23 changes: 23 additions & 0 deletions src/test/ui/type-alias-impl-trait/issue-57611-trait-alias.stderr
Original file line number Diff line number Diff line change
@@ -0,0 +1,23 @@
error[E0631]: type mismatch in closure arguments
--> $DIR/issue-57611-trait-alias.rs:17:5
|
LL | type Bar = impl Baz<Self, Self>;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected signature of `for<'r> fn(&'r X) -> _`
...
LL | |x| x
| ----- found signature of `fn(_) -> _`
|
= note: the return type of a function must have a statically known size

error[E0271]: type mismatch resolving `for<'r> <[closure@$DIR/issue-57611-trait-alias.rs:21:9: 21:14] as std::ops::FnOnce<(&'r X,)>>::Output == &'r X`
--> $DIR/issue-57611-trait-alias.rs:17:5
|
LL | type Bar = impl Baz<Self, Self>;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected bound lifetime parameter, found concrete lifetime
|
= note: the return type of a function must have a statically known size

error: aborting due to 2 previous errors

Some errors have detailed explanations: E0271, E0631.
For more information about an error, try `rustc --explain E0271`.
31 changes: 31 additions & 0 deletions src/test/ui/type-alias-impl-trait/issue-57807-associated-type.rs
Original file line number Diff line number Diff line change
@@ -0,0 +1,31 @@
// Regression test for issue #57807 - ensure
// that we properly unify associated types within
// a type alias impl trait
// check-pass
#![feature(type_alias_impl_trait)]

trait Bar {
type A;
}

impl Bar for () {
type A = ();
}

trait Foo {
type A;
type B: Bar<A = Self::A>;

fn foo() -> Self::B;
}

impl Foo for () {
type A = ();
type B = impl Bar<A = Self::A>;

fn foo() -> Self::B {
()
}
}

fn main() {}