tests/ui/unnecessary_lazy_eval.fixed

   1 // run-rustfix
   2 #![warn(clippy::unnecessary_lazy_evaluations)]
   3 #![allow(clippy::redundant_closure)]
   4 #![allow(clippy::bind_instead_of_map)]
   5
   6 struct Deep(Option<usize>);
   7
   8 #[derive(Copy, Clone)]
   9 struct SomeStruct {
  10     some_field: usize,
  11 }
  12
  13 impl SomeStruct {
  14     fn return_some_field(&self) -> usize {
  15         self.some_field
  16     }
  17 }
  18
  19 fn some_call<T: Default>() -> T {
  20     T::default()
  21 }
  22
  23 fn main() {
  24     let astronomers_pi = 10;
  25     let ext_arr: [usize; 1] = [2];
  26     let ext_str = SomeStruct { some_field: 10 };
  27
  28     let mut opt = Some(42);
  29     let ext_opt = Some(42);
  30     let nested_opt = Some(Some(42));
  31     let nested_tuple_opt = Some(Some((42, 43)));
  32
  33     // Should lint - Option
  34     let _ = opt.unwrap_or(2);
  35     let _ = opt.unwrap_or(astronomers_pi);
  36     let _ = opt.unwrap_or(ext_str.some_field);
  37     let _ = opt.unwrap_or(ext_arr[0]);
  38     let _ = opt.and(ext_opt);
  39     let _ = opt.or(ext_opt);
  40     let _ = opt.or(None);
  41     let _ = opt.get_or_insert(2);
  42     let _ = opt.ok_or(2);
  43     let _ = opt.ok_or(ext_arr[0]);
  44
  45     // Cases when unwrap is not called on a simple variable
  46     let _ = Some(10).unwrap_or(2);
  47     let _ = Some(10).and(ext_opt);
  48     let _: Option<usize> = None.or(ext_opt);
  49     let _ = None.get_or_insert(2);
  50     let _: Result<usize, usize> = None.ok_or(2);
  51     let _: Option<usize> = None.or(None);
  52
  53     let mut deep = Deep(Some(42));
  54     let _ = deep.0.unwrap_or(2);
  55     let _ = deep.0.and(ext_opt);
  56     let _ = deep.0.or(None);
  57     let _ = deep.0.get_or_insert(2);
  58     let _ = deep.0.ok_or(2);
  59
  60     // Should not lint - Option
  61     let _ = opt.unwrap_or_else(|| ext_str.return_some_field());
  62     let _ = nested_opt.unwrap_or_else(|| Some(some_call()));
  63     let _ = nested_tuple_opt.unwrap_or_else(|| Some((1, 2)));
  64     let _ = nested_tuple_opt.unwrap_or_else(|| Some((some_call(), some_call())));
  65     let _ = opt.or_else(some_call);
  66     let _ = opt.or_else(|| some_call());
  67     let _: Result<usize, usize> = opt.ok_or_else(|| some_call());
  68     let _: Result<usize, usize> = opt.ok_or_else(some_call);
  69     let _ = deep.0.get_or_insert_with(|| some_call());
  70     let _ = deep.0.or_else(some_call);
  71     let _ = deep.0.or_else(|| some_call());
  72
  73     // These are handled by bind_instead_of_map
  74     let _ = Some(10).and_then(|idx| Some(ext_arr[idx]));
  75     let _ = Some(10).and_then(|idx| Some(idx));
  76     let _: Option<usize> = None.or_else(|| Some(3));
  77     let _ = deep.0.or_else(|| Some(3));
  78     let _ = opt.or_else(|| Some(3));
  79
  80     // Should lint - Result
  81     let res: Result<usize, usize> = Err(5);
  82     let res2: Result<usize, SomeStruct> = Err(SomeStruct { some_field: 5 });
  83
  84     let _ = res2.unwrap_or(2);
  85     let _ = res2.unwrap_or(astronomers_pi);
  86     let _ = res2.unwrap_or(ext_str.some_field);
  87
  88     // Should not lint - Result
  89     let _ = res.unwrap_or_else(|err| err);
  90     let _ = res.unwrap_or_else(|err| ext_arr[err]);
  91     let _ = res2.unwrap_or_else(|err| err.some_field);
  92     let _ = res2.unwrap_or_else(|err| err.return_some_field());
  93     let _ = res2.unwrap_or_else(|_| ext_str.return_some_field());
  94
  95     let _: Result<usize, usize> = res.and_then(|x| Ok(x));
  96     let _: Result<usize, usize> = res.and_then(|x| Err(x));
  97
  98     let _: Result<usize, usize> = res.or_else(|err| Ok(err));
  99     let _: Result<usize, usize> = res.or_else(|err| Err(err));
 100
 101     // These are handled by bind_instead_of_map
 102     let _: Result<usize, usize> = res.and_then(|_| Ok(2));
 103     let _: Result<usize, usize> = res.and_then(|_| Ok(astronomers_pi));
 104     let _: Result<usize, usize> = res.and_then(|_| Ok(ext_str.some_field));
 105
 106     let _: Result<usize, usize> = res.and_then(|_| Err(2));
 107     let _: Result<usize, usize> = res.and_then(|_| Err(astronomers_pi));
 108     let _: Result<usize, usize> = res.and_then(|_| Err(ext_str.some_field));
 109
 110     let _: Result<usize, usize> = res.or_else(|_| Ok(2));
 111     let _: Result<usize, usize> = res.or_else(|_| Ok(astronomers_pi));
 112     let _: Result<usize, usize> = res.or_else(|_| Ok(ext_str.some_field));
 113
 114     let _: Result<usize, usize> = res.or_else(|_| Err(2));
 115     let _: Result<usize, usize> = res.or_else(|_| Err(astronomers_pi));
 116     let _: Result<usize, usize> = res.or_else(|_| Err(ext_str.some_field));
 117 }