rust/tests/ui/deriving/deriving-default-enum.rs
2024-06-25 23:29:44 +08:00

28 lines
538 B
Rust

//@ run-pass
// nb: does not impl Default
#[derive(Debug, PartialEq)]
struct NotDefault;
#[derive(Debug, Default, PartialEq)]
enum Foo {
#[default]
Alpha,
#[allow(dead_code)]
Beta(NotDefault),
}
// #[default] on a generic enum does not add `Default` bounds to the type params.
#[derive(Default)]
enum MyOption<T> {
#[default]
None,
#[allow(dead_code)]
Some(T),
}
fn main() {
assert!(matches!(Foo::default(), Foo::Alpha));
assert!(matches!(MyOption::<NotDefault>::default(), MyOption::None));
}