src/tools/clippy/tests/ui/comparison_to_empty.fixed

   1 #![warn(clippy::comparison_to_empty)]
   2 #![allow(clippy::borrow_deref_ref, clippy::needless_if, clippy::useless_vec)]
   3 #![feature(let_chains)]
   4
   5 fn main() {
   6     // Disallow comparisons to empty
   7     let s = String::new();
   8     let _ = s.is_empty();
   9     let _ = !s.is_empty();
  10
  11     let v = vec![0];
  12     let _ = v.is_empty();
  13     let _ = !v.is_empty();
  14     if (*v).is_empty() {}
  15     let s = [0].as_slice();
  16     if s.is_empty() {}
  17     if s.is_empty() {}
  18     if s.is_empty() && s.is_empty() {}
  19
  20     // Allow comparisons to non-empty
  21     let s = String::new();
  22     let _ = s == " ";
  23     let _ = s != " ";
  24
  25     let v = vec![0];
  26     let _ = v == [0];
  27     let _ = v != [0];
  28     if let [0] = &*v {}
  29     let s = [0].as_slice();
  30     if let [0] = s {}
  31     if let [0] = &*s && s == [0] {}
  32 }