//@ run-rustfix #![feature(impl_trait_in_fn_trait_return)] #![deny(unused_parens)] #![allow(while_true)] // for rustfix #[derive(Eq, PartialEq)] struct X { y: bool } impl X { fn foo(&self, conjunct: bool) -> bool { self.y && conjunct } } fn foo() -> isize { return (1); //~ ERROR unnecessary parentheses around `return` value } fn bar(y: bool) -> X { return (X { y }); //~ ERROR unnecessary parentheses around `return` value } pub fn around_return_type() -> (u32) { //~ ERROR unnecessary parentheses around type panic!() } pub fn around_block_return() -> u32 { let _foo = { (5) //~ ERROR unnecessary parentheses around block return value }; (5) //~ ERROR unnecessary parentheses around block return value } pub trait Trait { fn test(&self); } pub fn around_multi_bound_ref() -> &'static (dyn Trait + Send) { panic!() } //~v ERROR unnecessary parentheses around type pub fn around_single_bound_ref() -> &'static (dyn Trait) { panic!() } pub fn around_multi_bound_ptr() -> *const (dyn Trait + Send) { panic!() } //~v ERROR unnecessary parentheses around type pub fn around_single_bound_ptr() -> *const (dyn Trait) { panic!() } pub fn around_multi_bound_dyn_fn_output() -> &'static dyn FnOnce() -> (impl Send + Sync) { &|| () } //~v ERROR unnecessary parentheses around type pub fn around_single_bound_dyn_fn_output() -> &'static dyn FnOnce() -> (impl Send) { &|| () } pub fn around_dyn_fn_output_given_more_bounds() -> &'static (dyn FnOnce() -> (impl Send) + Sync) { &|| () } pub fn around_multi_bound_impl_fn_output() -> impl FnOnce() -> (impl Send + Sync) { || () } //~v ERROR unnecessary parentheses around type pub fn around_single_bound_impl_fn_output() -> impl FnOnce() -> (impl Send) { || () } pub fn around_impl_fn_output_given_more_bounds() -> impl FnOnce() -> (impl Send) + Sync { || () } //~v ERROR unnecessary parentheses around type pub fn around_dyn_bound() -> &'static dyn (FnOnce()) { &|| () } //~v ERROR unnecessary parentheses around type pub fn around_impl_trait_bound() -> impl (FnOnce()) { || () } // these parens aren't strictly required but they help disambiguate => no lint pub fn around_fn_bound_with_explicit_ret_ty() -> impl (Fn() -> ()) + Send { || () } //~v ERROR unnecessary parentheses around type pub fn around_fn_bound_with_implicit_ret_ty() -> impl (Fn()) + Send { || () } //~v ERROR unnecessary parentheses around type pub fn around_last_fn_bound_with_explicit_ret_ty() -> impl Send + (Fn() -> ()) { || () } //~v ERROR unnecessary parentheses around type pub fn around_regular_bound1() -> &'static (dyn (Send) + Sync) { &|| () } //~v ERROR unnecessary parentheses around type pub fn around_regular_bound2() -> &'static (dyn Send + (Sync)) { &|| () } //~v ERROR unnecessary parentheses around type pub fn around_regular_bound3() -> &'static (dyn Send + (::std::marker::Sync)) { &|| () } pub fn parens_with_keyword(e: &[()]) -> i32 { if(true) {} //~ ERROR unnecessary parentheses around `if` while(true) {} //~ ERROR unnecessary parentheses around `while` for _ in(e) {} //~ ERROR unnecessary parentheses around `for` match(1) { _ => ()} //~ ERROR unnecessary parentheses around `match` return(1); //~ ERROR unnecessary parentheses around `return` value } macro_rules! baz { ($($foo:expr),+) => { ($($foo),*) }; } macro_rules! unit { () => { () }; } struct One; impl std::ops::Sub for () { type Output = i32; fn sub(self, _: One) -> Self::Output { -1 } } impl std::ops::Neg for One { type Output = i32; fn neg(self) -> Self::Output { -1 } } pub const CONST_ITEM: usize = (10); //~ ERROR unnecessary parentheses around assigned value pub static STATIC_ITEM: usize = (10); //~ ERROR unnecessary parentheses around assigned value fn main() { foo(); bar((true)); //~ ERROR unnecessary parentheses around function argument if (true) {} //~ ERROR unnecessary parentheses around `if` condition while (true) {} //~ ERROR unnecessary parentheses around `while` condition match (true) { //~ ERROR unnecessary parentheses around `match` scrutinee expression _ => {} } if let 1 = (1) {} //~ ERROR unnecessary parentheses around `let` scrutinee expression while let 1 = (2) {} //~ ERROR unnecessary parentheses around `let` scrutinee expression let v = X { y: false }; // struct lits needs parens, so these shouldn't warn. if (v == X { y: true }) {} if (X { y: true } == v) {} if (X { y: false }.y) {} // this shouldn't warn, because the parens are necessary to disambiguate let chains if let true = (true && false) {} while (X { y: false }.foo(true)) {} while (true | X { y: false }.y) {} match (X { y: false }) { _ => {} } X { y: false }.foo((true)); //~ ERROR unnecessary parentheses around method argument let mut _a = (0); //~ ERROR unnecessary parentheses around assigned value _a = (0); //~ ERROR unnecessary parentheses around assigned value _a += (1); //~ ERROR unnecessary parentheses around assigned value let(mut _a) = 3; //~ ERROR unnecessary parentheses around pattern let (mut _a) = 3; //~ ERROR unnecessary parentheses around pattern let( mut _a) = 3; //~ ERROR unnecessary parentheses around pattern let(_a) = 3; //~ ERROR unnecessary parentheses around pattern let (_a) = 3; //~ ERROR unnecessary parentheses around pattern let( _a) = 3; //~ ERROR unnecessary parentheses around pattern let _a = baz!(3, 4); let _b = baz!(3); let _ = { (unit!() - One) //~ ERROR unnecessary parentheses around block return value } + { (unit![] - One) //~ ERROR unnecessary parentheses around block return value } + { // FIXME: false positive. This parenthesis is required. (unit! {} - One) //~ ERROR unnecessary parentheses around block return value }; // Do *not* lint around `&raw` (but do lint when `&` creates a reference). let mut x = 0; let _r = (&x); //~ ERROR unnecessary parentheses let _r = (&mut x); //~ ERROR unnecessary parentheses let _r = (&raw const x); let _r = (&raw mut x); }