lib.rs

#![allow(unused)]
pub fn add(left: usize, right: usize) -> usize {
    left + right
}

#[derive(Debug)]
pub struct Rectangle {
    width: u32,
    height: u32,
}

impl Rectangle {
    pub fn can_hold(&self, other: &Rectangle) -> bool {
        self.width < other.width && self.height > other.height
    }
}

pub fn add_two(a: i32) -> i32 {
    a + 2
}

// pub fn greeting(name: &str) -> String {
//     format!("Hello {}!", name)
// }

pub fn greeting(name: &str) -> String {
    String::from("Hello!")
}


pub struct Guess {    
    value: i32,
}

// impl Guess {
//     pub fn new(value: i32) -> Guess {
//         if value < 1 {
//             panic!("Guess value must be between 1 and 100, got {}.", value);
//         }

//         Guess {
//             value
//         }
//     }
// }

impl Guess {
    pub fn new(value: i32) -> Guess {
        if value < 1 {
            panic!("Guess value must be greater than or equal to 1, got {}.",
                   value);
        } else if value > 100 {
            panic!("Guess value must be less than or equal to 100, got {}.",
                   value);
        }

        Guess {
            value
        }
    }
}

fn prints_and_returns_10(a: i32) -> i32 {
    println!("I got the value {}", a);
    10
}

pub fn add_two2(a: i32) -> i32 {
    internal_adder(a, 2)
}

fn internal_adder(a: i32, b: i32) -> i32 {
    a + b
}

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

    #[test]
    fn exploration() {
        let result = add(2, 2);
        assert_eq!(result, 4);
    }

    #[test]
    fn another() {
        panic!("Make this test fail");
    }

    #[test]
    fn larger_can_hold_smaller() {
        let larger = Rectangle { width: 8, height: 7 };
        let smaller = Rectangle { width: 5, height: 1 };

        assert!(larger.can_hold(&smaller));
    }

    #[test]
    fn smaller_cannot_hold_larger() {
        let larger = Rectangle { width: 8, height: 7 };
        let smaller = Rectangle { width: 5, height: 1 };

        assert!(!smaller.can_hold(&larger));
    }

    #[test]
    fn it_adds_two() {
        assert_eq!(4, add_two(2));
    }

    // #[test]
    // fn greeting_contains_name() {
    //     let result = greeting("Carol");
    //     assert!(result.contains("Carol"));
    // }

    #[test]
    fn greeting_contains_name() {
        let result = greeting("Carol");
    assert!(
        result.contains("Carol"),
        "Greeting did not contain name, value was `{}`", result
        );
    }
    
    // #[test]
    // #[should_panic]
    // fn greater_than_100() {
    //     Guess::new(200);
    // }
    
    #[test]
    #[should_panic(expected = "Guess value must be less than or equal to 100")]
    fn greater_than_100() {
        Guess::new(0);
    }

    #[test]
    fn it_works() -> Result<(), String> {
        if 2 + 2 == 4 {
            Ok(())
        } else {
            Err(String::from("two plus two does not equal four"))
        }
    }

    #[test]
    fn this_test_will_pass() {
        let value = prints_and_returns_10(4);
        assert_eq!(10, value);
    }

    #[test]
    fn this_test_will_fail() {
        let value = prints_and_returns_10(8);
        assert_eq!(5, value);
    }

    #[test]
    fn add_two_and_two() {
        assert_eq!(4, add_two(2));
    }

    #[test]
    fn add_three_and_two() {
        assert_eq!(5, add_two(3));
    }

    #[test]
    fn one_hundred() {
        assert_eq!(102, add_two(100));
    }

    #[test]
    #[ignore]
    fn expensive_test() {
        // 需要运行一个小时的代码
    }

    #[test]
    fn internal() {
        assert_eq!(4, internal_adder(2, 2));
    }

}