1  #[derive(PartialEq, Debug)]
 2  struct Shoe {
 3      size: u32,
 4      style: String,
 5  }
 6  
 7  fn shoes_in_size(shoes: Vec<Shoe>, shoe_size: u32) -> Vec<Shoe> {
 8      shoes.into_iter().filter(|s| s.size == shoe_size).collect()
 9  }
10  
11  #[cfg(test)]
12  mod tests {
13      use super::*;
14  
15      #[test]
16      fn filters_by_size() {
17          let shoes = vec![
18              Shoe {
19                  size: 10,
20                  style: String::from("sneaker"),
21              },
22              Shoe {
23                  size: 13,
24                  style: String::from("sandal"),
25              },
26              Shoe {
27                  size: 10,
28                  style: String::from("boot"),
29              },
30          ];
31  
32          let in_my_size = shoes_in_size(shoes, 10);
33  
34          assert_eq!(
35              in_my_size,
36              vec![
37                  Shoe {
38                      size: 10,
39                      style: String::from("sneaker")
40                  },
41                  Shoe {
42                      size: 10,
43                      style: String::from("boot")
44                  },
45              ]
46          );
47      }
48  }