rust/tests/ui/traits/multidispatch-infer-convert-target.rs
2024-02-16 20:02:50 +00:00

37 lines
701 B
Rust

//@ run-pass
// Test that we can infer the Target based on the Self or vice versa.
use std::mem;
trait Convert<Target> {
fn convert(&self) -> Target; //~ WARN method `convert` is never used
}
impl Convert<u32> for i16 {
fn convert(&self) -> u32 {
*self as u32
}
}
impl Convert<i16> for u32 {
fn convert(&self) -> i16 {
*self as i16
}
}
fn test<T,U>(_: T, _: U, t_size: usize, u_size: usize)
where T : Convert<U>
{
assert_eq!(mem::size_of::<T>(), t_size);
assert_eq!(mem::size_of::<U>(), u_size);
}
fn main() {
// T = i16, U = u32
test(22_i16, Default::default(), 2, 4);
// T = u32, U = i16
test(22_u32, Default::default(), 4, 2);
}