rustlings/exercises/11_hashmaps/hashmaps2.rs
2024-06-24 16:50:03 +02:00

97 lines
2.7 KiB
Rust

// We're collecting different fruits to bake a delicious fruit cake. For this,
// we have a basket, which we'll represent in the form of a hash map. The key
// represents the name of each fruit we collect and the value represents how
// many of that particular fruit we have collected. Three types of fruits -
// Apple (4), Mango (2) and Lychee (5) are already in the basket hash map. You
// must add fruit to the basket so that there is at least one of each kind and
// more than 11 in total - we have a lot of mouths to feed. You are not allowed
// to insert any more of these fruits!
use std::collections::HashMap;
#[derive(Hash, PartialEq, Eq, Debug)]
enum Fruit {
Apple,
Banana,
Mango,
Lychee,
Pineapple,
}
fn fruit_basket(basket: &mut HashMap<Fruit, u32>) {
let fruit_kinds = [
Fruit::Apple,
Fruit::Banana,
Fruit::Mango,
Fruit::Lychee,
Fruit::Pineapple,
];
for fruit in fruit_kinds {
// TODO: Insert new fruits if they are not already present in the
// basket. Note that you are not allowed to put any type of fruit that's
// already present!
}
}
fn main() {
// You can optionally experiment here.
}
#[cfg(test)]
mod tests {
use super::*;
// Don't modify this function!
fn get_fruit_basket() -> HashMap<Fruit, u32> {
let content = [(Fruit::Apple, 4), (Fruit::Mango, 2), (Fruit::Lychee, 5)];
HashMap::from_iter(content)
}
#[test]
fn test_given_fruits_are_not_modified() {
let mut basket = get_fruit_basket();
fruit_basket(&mut basket);
assert_eq!(*basket.get(&Fruit::Apple).unwrap(), 4);
assert_eq!(*basket.get(&Fruit::Mango).unwrap(), 2);
assert_eq!(*basket.get(&Fruit::Lychee).unwrap(), 5);
}
#[test]
fn at_least_five_types_of_fruits() {
let mut basket = get_fruit_basket();
fruit_basket(&mut basket);
let count_fruit_kinds = basket.len();
assert!(count_fruit_kinds >= 5);
}
#[test]
fn greater_than_eleven_fruits() {
let mut basket = get_fruit_basket();
fruit_basket(&mut basket);
let count = basket.values().sum::<u32>();
assert!(count > 11);
}
#[test]
fn all_fruit_types_in_basket() {
let fruit_kinds = [
Fruit::Apple,
Fruit::Banana,
Fruit::Mango,
Fruit::Lychee,
Fruit::Pineapple,
];
let mut basket = get_fruit_basket();
fruit_basket(&mut basket);
for fruit_kind in fruit_kinds {
let Some(amount) = basket.get(&fruit_kind) else {
panic!("Fruit kind {fruit_kind:?} was not found in basket");
};
assert!(*amount > 0);
}
}
}