src/test/ui/type/type-check/assignment-in-if.rs

   1 // Test that the parser does not attempt to parse struct literals
   2 // within assignments in if expressions.
   3
   4 #![allow(unused_parens)]
   5
   6 struct Foo {
   7     foo: usize
   8 }
   9
  10 fn main() {
  11     let x = 1;
  12     let y: Foo;
  13
  14     // `x { ... }` should not be interpreted as a struct literal here
  15     if x = x {
  16         //~^ ERROR mismatched types
  17         println!("{}", x);
  18     }
  19     // Explicit parentheses on the left should match behavior of above
  20     if (x = x) {
  21         //~^ ERROR mismatched types
  22         println!("{}", x);
  23     }
  24     // The struct literal interpretation is fine with explicit parentheses on the right
  25     if y = (Foo { foo: x }) {
  26         //~^ ERROR mismatched types
  27         println!("{}", x);
  28     }
  29     // "invalid left-hand side of assignment" error is suppresed
  30     if 3 = x {
  31         //~^ ERROR mismatched types
  32         println!("{}", x);
  33     }
  34     if (
  35         if true {
  36             x = 4 //~ ERROR mismatched types
  37         } else {
  38             x = 5 //~ ERROR mismatched types
  39         }
  40     ) {
  41         println!("{}", x);
  42     }
  43
  44     if x == x && x = x && x == x {
  45         //~^ ERROR mismatched types
  46         //~| ERROR mismatched types
  47         //~| ERROR mismatched types
  48         println!("{}", x);
  49     }
  50
  51     if x == x && x == x && x = x {
  52         //~^ ERROR mismatched types
  53         //~| ERROR mismatched types
  54         println!("{}", x);
  55     }
  56
  57     if x = 1 && x == 1 {
  58         //~^ ERROR mismatched types
  59         //~| ERROR mismatched types
  60         println!("{}", x);
  61     }
  62 }