1 // Regression test: if we suggest replacing an `impl Trait` argument to an async
2 // fn with a named type parameter in order to add bounds, the suggested function
3 // signature should be well-formed.
4 //
5 // edition:2018
6
7 trait Foo {
8 type Bar;
bar(&self) -> Self::Bar9 fn bar(&self) -> Self::Bar;
10 }
11
run(_: &(), foo: impl Foo) -> std::io::Result<()>12 async fn run(_: &(), foo: impl Foo) -> std::io::Result<()> {
13 let bar = foo.bar();
14 assert_is_send(&bar);
15 //~^ ERROR: `<impl Foo as Foo>::Bar` cannot be sent between threads safely
16
17 Ok(())
18 }
19
20 // Test our handling of cases where there is a generic parameter list in the
21 // source, but only synthetic generic parameters
run2< >(_: &(), foo: impl Foo) -> std::io::Result<()>22 async fn run2< >(_: &(), foo: impl Foo) -> std::io::Result<()> {
23 let bar = foo.bar();
24 assert_is_send(&bar);
25 //~^ ERROR: `<impl Foo as Foo>::Bar` cannot be sent between threads safely
26
27 Ok(())
28 }
29
assert_is_send<T: Send>(_: &T)30 fn assert_is_send<T: Send>(_: &T) {}
31
main()32 fn main() {}
33