rust/tests/ui/specialization/specialization-basics.rs
2024-02-16 20:02:50 +00:00

99 lines
2.0 KiB
Rust

//@ run-pass
#![feature(specialization)] //~ WARN the feature `specialization` is incomplete
// Tests a variety of basic specialization scenarios and method
// dispatch for them.
trait Foo {
fn foo(&self) -> &'static str;
}
impl<T> Foo for T {
default fn foo(&self) -> &'static str {
"generic"
}
}
impl<T: Clone> Foo for T {
default fn foo(&self) -> &'static str {
"generic Clone"
}
}
impl<T, U> Foo for (T, U) where T: Clone, U: Clone {
default fn foo(&self) -> &'static str {
"generic pair"
}
}
impl<T: Clone> Foo for (T, T) {
default fn foo(&self) -> &'static str {
"generic uniform pair"
}
}
impl Foo for (u8, u32) {
default fn foo(&self) -> &'static str {
"(u8, u32)"
}
}
impl Foo for (u8, u8) {
default fn foo(&self) -> &'static str {
"(u8, u8)"
}
}
impl<T: Clone> Foo for Vec<T> {
default fn foo(&self) -> &'static str {
"generic Vec"
}
}
impl Foo for Vec<i32> {
fn foo(&self) -> &'static str {
"Vec<i32>"
}
}
impl Foo for String {
fn foo(&self) -> &'static str {
"String"
}
}
impl Foo for i32 {
fn foo(&self) -> &'static str {
"i32"
}
}
struct NotClone;
trait MyMarker {}
impl<T: Clone + MyMarker> Foo for T {
default fn foo(&self) -> &'static str {
"generic Clone + MyMarker"
}
}
#[derive(Clone)]
struct MarkedAndClone;
impl MyMarker for MarkedAndClone {}
fn main() {
assert!(NotClone.foo() == "generic");
assert!(0u8.foo() == "generic Clone");
assert!(vec![NotClone].foo() == "generic");
assert!(vec![0u8].foo() == "generic Vec");
assert!(vec![0i32].foo() == "Vec<i32>");
assert!(0i32.foo() == "i32");
assert!(String::new().foo() == "String");
assert!(((), 0).foo() == "generic pair");
assert!(((), ()).foo() == "generic uniform pair");
assert!((0u8, 0u32).foo() == "(u8, u32)");
assert!((0u8, 0u8).foo() == "(u8, u8)");
assert!(MarkedAndClone.foo() == "generic Clone + MyMarker");
}