rustlings/exercises/12_options/options1.rs

37 lines
1.1 KiB
Rust

// This function returns how much icecream there is left in the fridge.
// If it's before 22:00 (24-hour system), then 5 scoops are left. At 22:00,
// someone eats it all, so no icecream is left (value 0). Return `None` if
// `hour_of_day` is higher than 23.
fn maybe_icecream(hour_of_day: u16) -> Option<u16> {
// TODO: Complete the function body.
}
fn main() {
// You can optionally experiment here.
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn raw_value() {
// TODO: Fix this test. How do you get the value contained in the
// Option?
let icecreams = maybe_icecream(12);
assert_eq!(icecreams, 5); // Don't change this line.
}
#[test]
fn check_icecream() {
assert_eq!(maybe_icecream(0), Some(5));
assert_eq!(maybe_icecream(9), Some(5));
assert_eq!(maybe_icecream(18), Some(5));
assert_eq!(maybe_icecream(22), Some(0));
assert_eq!(maybe_icecream(23), Some(0));
assert_eq!(maybe_icecream(24), None);
assert_eq!(maybe_icecream(25), None);
}
}