Rust中的测试用例的写法

有点类似

#[derive(Debug)]
pub struct Rectangle {
    length: u32,
    width: u32,
}
 
impl Rectangle {
    pub fn can_hold(&self, other: &Rectangle) -> bool {
    self.length > other.length && self.width > other.width
    }
}
 
pub fn add_two(a: i32) -> i32 {
    a +
}
 
pub fn greeting(name: &str) -> String {
    format!("Hello {}!", name)
}
 
pub struct Guess {
    value: i32,
}
 
impl Guess {
    pub fn new(value: i32) -> Guess {
     {
        panic!("Guess value must be great than or equal 1, got {}.", value);
    }  {
        panic!("Guess value must less than or equal to 100, got {}.", value);
    }
 
    Guess {
        value
    }
    }
}
 
#[cfg(test)]
mod tests {
    use super::*;
 
    #[test]
    fn larger_can_hold_smaller() {
    let larger = Rectangle { length: , width:  };
    let smaller = Rectangle { length: , width:  };
    assert!(larger.can_hold(&smaller));
    }
 
    #[test]
    fn smaller_cannot_hold_larger() {
    let larger = Rectangle { length: , width:  };
        let smaller = Rectangle { length: , width:  };
        assert!(!smaller.can_hold(&larger));
    }
 
    #[test]
    fn it_add_two() {
    assert_eq!(, add_two());
    }
 
    #[test]
    fn greeting_contains_name() {
    let result = greeting("Carol");
     assert!(result.contains("Carol"));
    }
 
    #[test]
    #[should_panic(expected = "Guess value must be less than or equal to 100")]
    fn greater_than_100() {
    Guess::);
    }
 
    /*
    #[test]
    fn it_works() -> Result<(), String> {
    if 2 + 2 == 4 {
        Ok(())
    } else {
        Err(String::from("two plus two does not equal four"))
       }
    }
    */
}