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

   1 // run-rustfix
   2
   3 #![warn(clippy::manual_map)]
   4 #![allow(
   5     clippy::no_effect,
   6     clippy::map_identity,
   7     clippy::unit_arg,
   8     clippy::match_ref_pats,
   9     clippy::redundant_pattern_matching,
  10     clippy::for_loops_over_fallibles,
  11     dead_code
  12 )]
  13
  14 fn main() {
  15     match Some(0) {
  16         Some(_) => Some(2),
  17         None::<u32> => None,
  18     };
  19
  20     match Some(0) {
  21         Some(x) => Some(x + 1),
  22         _ => None,
  23     };
  24
  25     match Some("") {
  26         Some(x) => Some(x.is_empty()),
  27         None => None,
  28     };
  29
  30     if let Some(x) = Some(0) {
  31         Some(!x)
  32     } else {
  33         None
  34     };
  35
  36     #[rustfmt::skip]
  37     match Some(0) {
  38         Some(x) => { Some(std::convert::identity(x)) }
  39         None => { None }
  40     };
  41
  42     match Some(&String::new()) {
  43         Some(x) => Some(str::len(x)),
  44         None => None,
  45     };
  46
  47     match Some(0) {
  48         Some(x) if false => Some(x + 1),
  49         _ => None,
  50     };
  51
  52     match &Some([0, 1]) {
  53         Some(x) => Some(x[0]),
  54         &None => None,
  55     };
  56
  57     match &Some(0) {
  58         &Some(x) => Some(x * 2),
  59         None => None,
  60     };
  61
  62     match Some(String::new()) {
  63         Some(ref x) => Some(x.is_empty()),
  64         _ => None,
  65     };
  66
  67     match &&Some(String::new()) {
  68         Some(x) => Some(x.len()),
  69         _ => None,
  70     };
  71
  72     match &&Some(0) {
  73         &&Some(x) => Some(x + x),
  74         &&_ => None,
  75     };
  76
  77     #[warn(clippy::option_map_unit_fn)]
  78     match &mut Some(String::new()) {
  79         Some(x) => Some(x.push_str("")),
  80         None => None,
  81     };
  82
  83     #[allow(clippy::option_map_unit_fn)]
  84     {
  85         match &mut Some(String::new()) {
  86             Some(x) => Some(x.push_str("")),
  87             None => None,
  88         };
  89     }
  90
  91     match &mut Some(String::new()) {
  92         Some(ref x) => Some(x.len()),
  93         None => None,
  94     };
  95
  96     match &mut &Some(String::new()) {
  97         Some(x) => Some(x.is_empty()),
  98         &mut _ => None,
  99     };
 100
 101     match Some((0, 1, 2)) {
 102         Some((x, y, z)) => Some(x + y + z),
 103         None => None,
 104     };
 105
 106     match Some([1, 2, 3]) {
 107         Some([first, ..]) => Some(first),
 108         None => None,
 109     };
 110
 111     match &Some((String::new(), "test")) {
 112         Some((x, y)) => Some((y, x)),
 113         None => None,
 114     };
 115
 116     match Some((String::new(), 0)) {
 117         Some((ref x, y)) => Some((y, x)),
 118         None => None,
 119     };
 120
 121     match Some(Some(0)) {
 122         Some(Some(_)) | Some(None) => Some(0),
 123         None => None,
 124     };
 125
 126     match Some(Some((0, 1))) {
 127         Some(Some((x, 1))) => Some(x),
 128         _ => None,
 129     };
 130
 131     // #6795
 132     fn f1() -> Result<(), ()> {
 133         let _ = match Some(Ok(())) {
 134             Some(x) => Some(x?),
 135             None => None,
 136         };
 137         Ok(())
 138     }
 139
 140     for &x in Some(Some(true)).iter() {
 141         let _ = match x {
 142             Some(x) => Some(if x { continue } else { x }),
 143             None => None,
 144         };
 145     }
 146
 147     // #6797
 148     let x1 = (Some(String::new()), 0);
 149     let x2 = x1.0;
 150     match x2 {
 151         Some(x) => Some((x, x1.1)),
 152         None => None,
 153     };
 154
 155     struct S1 {
 156         x: Option<String>,
 157         y: u32,
 158     }
 159     impl S1 {
 160         fn f(self) -> Option<(String, u32)> {
 161             match self.x {
 162                 Some(x) => Some((x, self.y)),
 163                 None => None,
 164             }
 165         }
 166     }
 167
 168     // #6811
 169     match Some(0) {
 170         Some(x) => Some(vec![x]),
 171         None => None,
 172     };
 173
 174     match option_env!("") {
 175         Some(x) => Some(String::from(x)),
 176         None => None,
 177     };
 178
 179     // #6819
 180     async fn f2(x: u32) -> u32 {
 181         x
 182     }
 183
 184     async fn f3() {
 185         match Some(0) {
 186             Some(x) => Some(f2(x).await),
 187             None => None,
 188         };
 189     }
 190
 191     // #6847
 192     if let Some(_) = Some(0) {
 193         Some(0)
 194     } else if let Some(x) = Some(0) {
 195         Some(x + 1)
 196     } else {
 197         None
 198     };
 199
 200     if true {
 201         Some(0)
 202     } else if let Some(x) = Some(0) {
 203         Some(x + 1)
 204     } else {
 205         None
 206     };
 207
 208     // #6967
 209     const fn f4() {
 210         match Some(0) {
 211             Some(x) => Some(x + 1),
 212             None => None,
 213         };
 214     }
 215
 216     // #7077
 217     let s = &String::new();
 218     #[allow(clippy::needless_match)]
 219     let _: Option<&str> = match Some(s) {
 220         Some(s) => Some(s),
 221         None => None,
 222     };
 223 }