47 lines
919 B
Rust
47 lines
919 B
Rust
// result1.rs
|
|
// Make this test pass! Scroll down for hints :)
|
|
|
|
#[derive(PartialEq, Debug)]
|
|
struct PositiveNonzeroInteger(u64);
|
|
|
|
#[derive(PartialEq, Debug)]
|
|
enum CreationError {
|
|
Negative,
|
|
Zero,
|
|
}
|
|
|
|
impl PositiveNonzeroInteger {
|
|
fn new(value: i64) -> Result<PositiveNonzeroInteger, CreationError> {
|
|
Ok(PositiveNonzeroInteger(value as u64))
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
fn test_creation() {
|
|
assert!(PositiveNonzeroInteger::new(10).is_ok());
|
|
assert_eq!(
|
|
Err(CreationError::Negative),
|
|
PositiveNonzeroInteger::new(-10)
|
|
);
|
|
assert_eq!(Err(CreationError::Zero), PositiveNonzeroInteger::new(0));
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
// `PositiveNonzeroInteger::new` is always creating a new instance and returning an `Ok` result.
|
|
// It should be doing some checking, returning an `Err` result if those checks fail, and only
|
|
// returning an `Ok` result if those checks determine that everything is... okay :)
|