src/tools/clippy/tests/ui/vec.rs

   1
   2
   3
   4 #![warn(useless_vec)]
   5
   6 #[derive(Debug)]
   7 struct NonCopy;
   8
   9 fn on_slice(_: &[u8]) {}
  10 #[allow(ptr_arg)]
  11 fn on_vec(_: &Vec<u8>) {}
  12
  13 struct Line {
  14     length: usize,
  15 }
  16
  17 impl Line {
  18     fn length(&self) -> usize {
  19         self.length
  20     }
  21 }
  22
  23 fn main() {
  24     on_slice(&vec![]);
  25     on_slice(&[]);
  26
  27     on_slice(&vec![1, 2]);
  28     on_slice(&[1, 2]);
  29
  30     on_slice(&vec ![1, 2]);
  31     on_slice(&[1, 2]);
  32
  33     on_slice(&vec!(1, 2));
  34     on_slice(&[1, 2]);
  35
  36     on_slice(&vec![1; 2]);
  37     on_slice(&[1; 2]);
  38
  39     on_vec(&vec![]);
  40     on_vec(&vec![1, 2]);
  41     on_vec(&vec![1; 2]);
  42
  43     // Now with non-constant expressions
  44     let line = Line { length: 2 };
  45
  46     on_slice(&vec![2; line.length]);
  47     on_slice(&vec![2; line.length()]);
  48
  49     for a in vec![1, 2, 3] {
  50         println!("{:?}", a);
  51     }
  52
  53     for a in vec![NonCopy, NonCopy] {
  54         println!("{:?}", a);
  55     }
  56 }