rust/library/core/tests/any.rs
Nick Cameron bb5db85f74 Add the Provider api to core::any
Signed-off-by: Nick Cameron <nrc@ncameron.org>
2022-06-06 12:10:13 +01:00

155 lines
3.4 KiB
Rust

use core::any::*;
#[derive(PartialEq, Debug)]
struct Test;
static TEST: &'static str = "Test";
#[test]
fn any_referenced() {
let (a, b, c) = (&5 as &dyn Any, &TEST as &dyn Any, &Test as &dyn Any);
assert!(a.is::<i32>());
assert!(!b.is::<i32>());
assert!(!c.is::<i32>());
assert!(!a.is::<&'static str>());
assert!(b.is::<&'static str>());
assert!(!c.is::<&'static str>());
assert!(!a.is::<Test>());
assert!(!b.is::<Test>());
assert!(c.is::<Test>());
}
#[test]
fn any_owning() {
let (a, b, c) = (
Box::new(5_usize) as Box<dyn Any>,
Box::new(TEST) as Box<dyn Any>,
Box::new(Test) as Box<dyn Any>,
);
assert!(a.is::<usize>());
assert!(!b.is::<usize>());
assert!(!c.is::<usize>());
assert!(!a.is::<&'static str>());
assert!(b.is::<&'static str>());
assert!(!c.is::<&'static str>());
assert!(!a.is::<Test>());
assert!(!b.is::<Test>());
assert!(c.is::<Test>());
}
#[test]
fn any_downcast_ref() {
let a = &5_usize as &dyn Any;
match a.downcast_ref::<usize>() {
Some(&5) => {}
x => panic!("Unexpected value {x:?}"),
}
match a.downcast_ref::<Test>() {
None => {}
x => panic!("Unexpected value {x:?}"),
}
}
#[test]
fn any_downcast_mut() {
let mut a = 5_usize;
let mut b: Box<_> = Box::new(7_usize);
let a_r = &mut a as &mut dyn Any;
let tmp: &mut usize = &mut *b;
let b_r = tmp as &mut dyn Any;
match a_r.downcast_mut::<usize>() {
Some(x) => {
assert_eq!(*x, 5);
*x = 612;
}
x => panic!("Unexpected value {x:?}"),
}
match b_r.downcast_mut::<usize>() {
Some(x) => {
assert_eq!(*x, 7);
*x = 413;
}
x => panic!("Unexpected value {x:?}"),
}
match a_r.downcast_mut::<Test>() {
None => (),
x => panic!("Unexpected value {x:?}"),
}
match b_r.downcast_mut::<Test>() {
None => (),
x => panic!("Unexpected value {x:?}"),
}
match a_r.downcast_mut::<usize>() {
Some(&mut 612) => {}
x => panic!("Unexpected value {x:?}"),
}
match b_r.downcast_mut::<usize>() {
Some(&mut 413) => {}
x => panic!("Unexpected value {x:?}"),
}
}
#[test]
fn any_fixed_vec() {
let test = [0_usize; 8];
let test = &test as &dyn Any;
assert!(test.is::<[usize; 8]>());
assert!(!test.is::<[usize; 10]>());
}
#[test]
fn any_unsized() {
fn is_any<T: Any + ?Sized>() {}
is_any::<[i32]>();
}
#[test]
fn distinct_type_names() {
// https://github.com/rust-lang/rust/issues/84666
struct Velocity(f32, f32);
fn type_name_of_val<T>(_: T) -> &'static str {
type_name::<T>()
}
assert_ne!(type_name_of_val(Velocity), type_name_of_val(Velocity(0.0, -9.8)),);
}
// Test the `Provider` API.
struct SomeConcreteType {
some_string: String,
}
impl Provider for SomeConcreteType {
fn provide<'a>(&'a self, req: &mut Demand<'a>) {
req.provide_ref::<String>(&self.some_string)
.provide_value::<String, _>(|| "bye".to_owned());
}
}
#[test]
fn test_provider() {
let obj: &dyn Provider = &SomeConcreteType { some_string: "hello".to_owned() };
assert_eq!(&**request_ref::<String>(obj).unwrap(), "hello");
assert_eq!(&*request_value::<String>(obj).unwrap(), "bye");
assert_eq!(request_value::<u8>(obj), None);
}