exercism-clock.rs

// My answer for Exercism's Clock exercise
use std::fmt;

#[derive(PartialEq)]
pub struct Clock {
    hours: i32,
    minutes: i32,
}

impl Clock {
    pub fn new(hours: i32, minutes: i32) -> Self {
        Self {
            hours,
            minutes,
        }
    }

    pub fn add_minutes(&self, minutes: i32) -> Self {
        let new_minutes = self.minutes + minutes;
        Self{
            hours: self.hours,
            minutes: new_minutes
        }
    }

    pub fn to_string(&self) -> String {
        let minutes_str = match self.minutes {
            x if x < 10 && x >= 0 => format!("0{}", self.minutes),
            _ => format!("{}", self.minutes),
        };

        let hours_str = match self.hours {
            x if x < 10 && x >= 0 => format!("0{}", self.hours),
            _ => format!("{}", self.hours),
        };

        format!("{}:{}", hours_str, minutes_str)
    }
}

impl fmt::Display for Clock {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(f, "{}", self.to_string())
    }
}

impl fmt::Debug for Clock {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(f, "{}", &self.to_string())
    }
}