src/test/ui/closures/2229_closure_analysis/pattern-matching-should-fail.rs

   1 #![feature(capture_disjoint_fields)]
   2 //~^ WARNING: the feature `capture_disjoint_fields` is incomplete
   3 //~| `#[warn(incomplete_features)]` on by default
   4 //~| see issue #53488 <https://github.com/rust-lang/rust/issues/53488>
   5 #![feature(never_type)]
   6
   7 // Should fake read the discriminant and throw an error
   8 fn test1() {
   9     let x: !;
  10     let c1 = || match x { };
  11     //~^ ERROR: use of possibly-uninitialized variable: `x`
  12 }
  13
  14 // Should fake read the discriminant and throw an error
  15 fn test2() {
  16     let x: !;
  17     let c2 = || match x { _ => () };
  18     //~^ ERROR: borrow of possibly-uninitialized variable: `x`
  19 }
  20
  21 // Testing single variant patterns
  22 enum SingleVariant {
  23     Points(u32)
  24 }
  25
  26 // Should fake read the discriminant and throw an error
  27 fn test3() {
  28     let variant: !;
  29     let c = || {
  30     //~^ ERROR: borrow of possibly-uninitialized variable: `variant`
  31         match variant {
  32             SingleVariant::Points(_) => {}
  33         }
  34     };
  35     c();
  36 }
  37
  38 // Should fake read the discriminant and throw an error
  39 fn test4() {
  40     let variant: !;
  41     let c = || {
  42     //~^ ERROR: borrow of possibly-uninitialized variable: `variant`
  43         match variant {
  44             SingleVariant::Points(a) => {
  45                 println!("{:?}", a);
  46             }
  47         }
  48     };
  49     c();
  50 }
  51
  52 fn test5() {
  53     let t: !;
  54     let g: !;
  55
  56     let a = || {
  57         match g { };
  58         //~^ ERROR: use of possibly-uninitialized variable: `g`
  59         let c = ||  {
  60             match t { };
  61             //~^ ERROR: use of possibly-uninitialized variable: `t`
  62         };
  63
  64         c();
  65     };
  66
  67 }
  68
  69 // Should fake read the discriminant and throw an error
  70 fn test6() {
  71     let x: u8;
  72     let c1 = || match x { };
  73     //~^ ERROR: use of possibly-uninitialized variable: `x`
  74     //~| ERROR: non-exhaustive patterns: type `u8` is non-empty
  75 }
  76
  77 fn main() {
  78     test1();
  79     test2();
  80     test3();
  81     test4();
  82     test5();
  83     test6();
  84 }