struct Rectangle { width: i32, height: i32, } impl Rectangle { // Don't change this function. fn new(width: i32, height: i32) -> Self { if width <= 0 || height <= 0 { // Returning a `Result` would be better here. But we want to learn // how to test functions that can panic. panic!("Rectangle width and height must be positive"); } Rectangle { width, height } } } fn main() { // You can optionally experiment here. } #[cfg(test)] mod tests { use super::*; #[test] fn correct_width_and_height() { let rect = Rectangle::new(10, 20); assert_eq!(rect.width, 10); // Check width assert_eq!(rect.height, 20); // Check height } #[test] #[should_panic] // Added this attribute to check that the test panics. fn negative_width() { let _rect = Rectangle::new(-10, 10); } #[test] #[should_panic] // Added this attribute to check that the test panics. fn negative_height() { let _rect = Rectangle::new(10, -10); } }