rust/tests/ui/dst/dst-bad-coerce1.rs

37 lines
818 B
Rust

// Attempt to change the type as well as unsizing.
#![feature(unsized_tuple_coercion)]
struct Fat<T: ?Sized> {
ptr: T
}
struct Foo;
trait Bar { fn bar(&self) {} }
pub fn main() {
// With a vec of isize.
let f1 = Fat { ptr: [1, 2, 3] };
let f2: &Fat<[isize; 3]> = &f1;
let f3: &Fat<[usize]> = f2;
//~^ ERROR mismatched types
// With a trait.
let f1 = Fat { ptr: Foo };
let f2: &Fat<Foo> = &f1;
let f3: &Fat<dyn Bar> = f2;
//~^ ERROR `Foo: Bar` is not satisfied
// Tuple with a vec of isize.
let f1 = ([1, 2, 3],);
let f2: &([isize; 3],) = &f1;
let f3: &([usize],) = f2;
//~^ ERROR mismatched types
// Tuple with a trait.
let f1 = (Foo,);
let f2: &(Foo,) = &f1;
let f3: &(dyn Bar,) = f2;
//~^ ERROR `Foo: Bar` is not satisfied
}