src/test/ui/pattern/usefulness/match-empty-exhaustive_patterns.rs

   1 #![feature(never_type)]
   2 #![feature(exhaustive_patterns)]
   3 #![deny(unreachable_patterns)]
   4 enum Foo {}
   5
   6 struct NonEmptyStruct(bool); //~ `NonEmptyStruct` defined here
   7 union NonEmptyUnion1 { //~ `NonEmptyUnion1` defined here
   8     foo: (),
   9 }
  10 union NonEmptyUnion2 { //~ `NonEmptyUnion2` defined here
  11     foo: (),
  12     bar: (),
  13 }
  14 enum NonEmptyEnum1 { //~ `NonEmptyEnum1` defined here
  15     Foo(bool),
  16     //~^ not covered
  17     //~| not covered
  18 }
  19 enum NonEmptyEnum2 { //~ `NonEmptyEnum2` defined here
  20     Foo(bool),
  21     //~^ not covered
  22     //~| not covered
  23     Bar,
  24     //~^ not covered
  25     //~| not covered
  26 }
  27 enum NonEmptyEnum5 { //~ `NonEmptyEnum5` defined here
  28     V1, V2, V3, V4, V5,
  29 }
  30
  31 macro_rules! match_empty {
  32     ($e:expr) => {
  33         match $e {}
  34     };
  35 }
  36 macro_rules! match_false {
  37     ($e:expr) => {
  38         match $e {
  39             _ if false => {}
  40         }
  41     };
  42 }
  43
  44 fn foo(x: Foo) {
  45     match_empty!(x); // ok
  46     match x {
  47         _ => {}, //~ ERROR unreachable pattern
  48     }
  49     match x {
  50         _ if false => {}, //~ ERROR unreachable pattern
  51     }
  52 }
  53
  54 fn main() {
  55     match None::<!> {
  56         None => {}
  57         Some(_) => {} //~ ERROR unreachable pattern
  58     }
  59     match None::<Foo> {
  60         None => {}
  61         Some(_) => {} //~ ERROR unreachable pattern
  62     }
  63
  64     match_empty!(0u8);
  65     //~^ ERROR type `u8` is non-empty
  66     match_empty!(NonEmptyStruct(true));
  67     //~^ ERROR type `NonEmptyStruct` is non-empty
  68     match_empty!((NonEmptyUnion1 { foo: () }));
  69     //~^ ERROR type `NonEmptyUnion1` is non-empty
  70     match_empty!((NonEmptyUnion2 { foo: () }));
  71     //~^ ERROR type `NonEmptyUnion2` is non-empty
  72     match_empty!(NonEmptyEnum1::Foo(true));
  73     //~^ ERROR `Foo(_)` not covered
  74     match_empty!(NonEmptyEnum2::Foo(true));
  75     //~^ ERROR `Foo(_)` and `Bar` not covered
  76     match_empty!(NonEmptyEnum5::V1);
  77     //~^ ERROR `V1`, `V2`, `V3` and 2 more not covered
  78
  79     match_false!(0u8);
  80     //~^ ERROR `_` not covered
  81     match_false!(NonEmptyStruct(true));
  82     //~^ ERROR `NonEmptyStruct(_)` not covered
  83     match_false!((NonEmptyUnion1 { foo: () }));
  84     //~^ ERROR `NonEmptyUnion1 { .. }` not covered
  85     match_false!((NonEmptyUnion2 { foo: () }));
  86     //~^ ERROR `NonEmptyUnion2 { .. }` not covered
  87     match_false!(NonEmptyEnum1::Foo(true));
  88     //~^ ERROR `Foo(_)` not covered
  89     match_false!(NonEmptyEnum2::Foo(true));
  90     //~^ ERROR `Foo(_)` and `Bar` not covered
  91     match_false!(NonEmptyEnum5::V1);
  92     //~^ ERROR `V1`, `V2`, `V3` and 2 more not covered
  93 }