diff options
Diffstat (limited to 'tests/ui/traits/alias')
-rw-r--r-- | tests/ui/traits/alias/dont-elaborate-non-self.rs | 10 | ||||
-rw-r--r-- | tests/ui/traits/alias/dont-elaborate-non-self.stderr | 20 |
2 files changed, 30 insertions, 0 deletions
diff --git a/tests/ui/traits/alias/dont-elaborate-non-self.rs b/tests/ui/traits/alias/dont-elaborate-non-self.rs new file mode 100644 index 000000000..4f9eaacb8 --- /dev/null +++ b/tests/ui/traits/alias/dont-elaborate-non-self.rs @@ -0,0 +1,10 @@ +#![feature(trait_alias)] + +use std::future::Future; + +trait F<Fut: Future<Output = usize>> = Fn() -> Fut; + +fn f<Fut>(a: dyn F<Fut>) {} +//~^ ERROR the size for values of type `(dyn Fn() -> Fut + 'static)` cannot be known at compilation time + +fn main() {} diff --git a/tests/ui/traits/alias/dont-elaborate-non-self.stderr b/tests/ui/traits/alias/dont-elaborate-non-self.stderr new file mode 100644 index 000000000..247a4f812 --- /dev/null +++ b/tests/ui/traits/alias/dont-elaborate-non-self.stderr @@ -0,0 +1,20 @@ +error[E0277]: the size for values of type `(dyn Fn() -> Fut + 'static)` cannot be known at compilation time + --> $DIR/dont-elaborate-non-self.rs:7:11 + | +LL | fn f<Fut>(a: dyn F<Fut>) {} + | ^ doesn't have a size known at compile-time + | + = help: the trait `Sized` is not implemented for `(dyn Fn() -> Fut + 'static)` + = help: unsized fn params are gated as an unstable feature +help: you can use `impl Trait` as the argument type + | +LL | fn f<Fut>(a: impl F<Fut>) {} + | ~~~~ +help: function arguments must have a statically known size, borrowed types always have a known size + | +LL | fn f<Fut>(a: &dyn F<Fut>) {} + | + + +error: aborting due to previous error + +For more information about this error, try `rustc --explain E0277`. |