rust/tests/ui/traits/inheritance/repeated-supertrait.rs

49 lines
1.3 KiB
Rust

//@ run-pass
// Test a case of a trait which extends the same supertrait twice, but
// with difference type parameters. Test that we can invoke the
// various methods in various ways successfully.
// See also `ui/traits/trait-repeated-supertrait-ambig.rs`.
trait CompareTo<T> {
fn same_as(&self, t: T) -> bool;
}
trait CompareToInts : CompareTo<i64> + CompareTo<u64> {
}
impl CompareTo<i64> for i64 {
fn same_as(&self, t: i64) -> bool { *self == t }
}
impl CompareTo<u64> for i64 {
fn same_as(&self, t: u64) -> bool { *self == (t as i64) }
}
impl CompareToInts for i64 { }
fn with_obj(c: &dyn CompareToInts) -> bool {
c.same_as(22_i64) && c.same_as(22_u64)
}
fn with_trait<C:CompareToInts>(c: &C) -> bool {
c.same_as(22_i64) && c.same_as(22_u64)
}
fn with_ufcs1<C:CompareToInts>(c: &C) -> bool {
<dyn CompareToInts>::same_as(c, 22_i64) && <dyn CompareToInts>::same_as(c, 22_u64)
}
fn with_ufcs2<C:CompareToInts>(c: &C) -> bool {
CompareTo::same_as(c, 22_i64) && CompareTo::same_as(c, 22_u64)
}
fn main() {
assert_eq!(22_i64.same_as(22_i64), true);
assert_eq!(22_i64.same_as(22_u64), true);
assert_eq!(with_trait(&22), true);
assert_eq!(with_obj(&22), true);
assert_eq!(with_ufcs1(&22), true);
assert_eq!(with_ufcs2(&22), true);
}