day2_part2.rs

fn main() {
    let input = read_input();
    let sum: u64 = input
        .iter()
        .map(|(shape, outcome)| {
            let action = match outcome {
                Outcome::Lose => loses_against,
                Outcome::Draw => draws_against,
                Outcome::Win => wins_against,
            };
            (action(*shape) as u32 + (*outcome as u32 * 3)) as u64
        })
        .sum();
    println!("Score: {}", sum);
}


#[cfg(test)]
mod tests {
    use super::*;

    use quickcheck::{Arbitrary, Gen};

    impl Arbitrary for Shape {
        fn arbitrary(g: &mut Gen) -> Self {
            let vals = &[
                Shape::Rock,
                Shape::Paper,
                Shape::Scissors,
            ];
            g.choose(vals).expect("choose value").clone()
        }
    }

    quickcheck! {
        fn prop_inverse(shape: Shape) -> bool {
            let winner = wins_against(shape);
            loses_against(winner) == shape
        }
    }
}