src/test/ui/lint/lint-unnecessary-parens.rs

   1 // run-rustfix
   2
   3 #![deny(unused_parens)]
   4 #![allow(while_true)] // for rustfix
   5
   6 #[derive(Eq, PartialEq)]
   7 struct X { y: bool }
   8 impl X {
   9     fn foo(&self, conjunct: bool) -> bool { self.y && conjunct }
  10 }
  11
  12 fn foo() -> isize {
  13     return (1); //~ ERROR unnecessary parentheses around `return` value
  14 }
  15 fn bar(y: bool) -> X {
  16     return (X { y }); //~ ERROR unnecessary parentheses around `return` value
  17 }
  18
  19 pub fn unused_parens_around_return_type() -> (u32) { //~ ERROR unnecessary parentheses around type
  20     panic!()
  21 }
  22
  23 pub fn unused_parens_around_block_return() -> u32 {
  24     let _foo = {
  25         (5) //~ ERROR unnecessary parentheses around block return value
  26     };
  27     (5) //~ ERROR unnecessary parentheses around block return value
  28 }
  29
  30 pub trait Trait {
  31     fn test(&self);
  32 }
  33
  34 pub fn passes_unused_parens_lint() -> &'static (dyn Trait) {
  35     panic!()
  36 }
  37
  38 macro_rules! baz {
  39     ($($foo:expr),+) => {
  40         ($($foo),*)
  41     }
  42 }
  43
  44 pub const CONST_ITEM: usize = (10); //~ ERROR unnecessary parentheses around assigned value
  45 pub static STATIC_ITEM: usize = (10); //~ ERROR unnecessary parentheses around assigned value
  46
  47 fn main() {
  48     foo();
  49     bar((true)); //~ ERROR unnecessary parentheses around function argument
  50
  51     if (true) {} //~ ERROR unnecessary parentheses around `if` condition
  52     while (true) {} //~ ERROR unnecessary parentheses around `while` condition
  53     match (true) { //~ ERROR unnecessary parentheses around `match` scrutinee expression
  54         _ => {}
  55     }
  56     if let 1 = (1) {} //~ ERROR unnecessary parentheses around `let` scrutinee expression
  57     while let 1 = (2) {} //~ ERROR unnecessary parentheses around `let` scrutinee expression
  58     let v = X { y: false };
  59     // struct lits needs parens, so these shouldn't warn.
  60     if (v == X { y: true }) {}
  61     if (X { y: true } == v) {}
  62     if (X { y: false }.y) {}
  63
  64     while (X { y: false }.foo(true)) {}
  65     while (true | X { y: false }.y) {}
  66
  67     match (X { y: false }) {
  68         _ => {}
  69     }
  70
  71     X { y: false }.foo((true)); //~ ERROR unnecessary parentheses around method argument
  72
  73     let mut _a = (0); //~ ERROR unnecessary parentheses around assigned value
  74     _a = (0); //~ ERROR unnecessary parentheses around assigned value
  75     _a += (1); //~ ERROR unnecessary parentheses around assigned value
  76
  77     let _a = baz!(3, 4);
  78     let _b = baz!(3);
  79 }